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Beijing, China

China University of Mining and Technology colloquially 矿大 is a national key university under the direct supervision of the Ministry of Education of China as well as a Project 211 and Project 985 university of China. The university consists of two parts, one located in Xuzhou, Jiangsu Province, the other located in Beijing with the name China University of Mining and Technology, Beijing . The latter is formerly the Graduate School of CUMT. CUMT is a leading multi-disciplinary polytechnic university with mining features. Wikipedia.


Chen L.,China University of Mining and Technology | Yu Z.,Shandong University
IEEE Transactions on Automatic Control | Year: 2015

In this technical note, we discuss a nonzero-sum stochastic differential game with delays. Not only the state variable, but also control variables of players involve delays. This kind of games are motivated by some interesting problems arising from economics and finance. Using anticipated backward stochastic differential equations, we establish a necessary condition and a sufficient condition of maximum principle for the delayed game problem. To explain theoretical results, we apply them to an economic problem. © 1963-2012 IEEE. Source


Guo X.Q.,China University of Mining and Technology | Guo X.Q.,McMaster University | Wu W.,University of Tennessee at Knoxville | Wu P.D.,McMaster University | And 3 more authors.
Scripta Materialia | Year: 2013

We experimentally and numerically study the large-strain free-end torsion of a rolled magnesium alloy. It is found that a torsion sample with its axial direction parallel to the normal direction elongates axially, while a sample with its axial direction along the rolling direction contracts axially. It is shown that this Swift effect, i.e., the second-order axial effect under free-end torsion, is mainly due to extension twinning. © 2013 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved. Source


Xiao S.,China University of Mining and Technology
Journal of Intelligent and Fuzzy Systems | Year: 2014

In this paper, we first introduce some operations on interval-valued intuitionistic fuzzy sets, such as Hamacher sum, Hamacher product, etc., and further develop the induced interval-valued intuitionistic fuzzy Hamacher ordered weighted geometric (I-IVIFHOWG) operator. We also establish some desirable properties of this operator, such as commutativity, idempotency and monotonicity. Then, we apply the induced interval-valued intuitionistic fuzzy Hamacher ordered weighted geometric (I-IVIFHOWG) operator to deal with the interval-valued intuitionistic fuzzy multiple attribute decision making problems. Finally, an illustrative example for evaluating the security of wireless sensor network is given to verify the developed approach and to demonstrate its practicality and effectiveness. © 2014 - IOS Press and the authors. All rights reserved. Source


Li Z.,China University of Mining and Technology | Sheng C.,Wuhan University of Technology
Journal of Nanoscience and Nanotechnology | Year: 2014

This review summarizes recent research and development of nanosensors applied to the food safety. Since the food safety is directly related to the people's health and life, the food detection has received considerable attentions. However, this food security has emerged in China as a severe problem in recent years. Food safety problems frequently compromised due to formaldehyde, poison vegetables, excessive pesticide residues, etc. These kinds of food contaminations could not be detected efficiently by traditional methods. Applying nanotechnology and nanominerals, various food contaminations can be identified accurately. Therefore nanosensors have been widely used in the food detection. We introduce current research on nanosensors followed by the industrial application of nanosensors. Finally, the challenges for the future food safety using nanosensors are discussed. Copyright © 2014 American Scientific Publishers All rights reserved. Source


Du Y.,China University of Mining and Technology | Du Y.,University of Twente | Schuur B.,University of Twente | Samori C.,University of Bologna | And 2 more authors.
Bioresource Technology | Year: 2013

Lipids from algal biomass may provide renewable fuel and chemical feedstock in large quantities. The energy intensity of drying and milling of algae prior to extraction and of solvent recovery afterwards is a major obstacle. The objective is to use switchable solvents to extract oil directly from wet microalgae slurries without the need for drying and milling, and subsequently recover the extracted oil and solvent by simple phase splitting, using CO2 as trigger. In this work secondary amine solvents were investigated for lipids extraction, polarity switching and phase splitting ability upon contacting with CO2. For strain Desmodesmus sp. extraction yields from the wet algal slurries, with and without cell disruption, were comparable with Bligh & Dyer method yields. Oil and solvent recovery via phase separation was realized by CO2 induced phase splitting, making secondary amines a candidate for further development of an energy efficient lipid extraction technology for non-broken microalgae. © 2013 Elsevier Ltd. Source


Meng Q.,China University of Mining and Technology
Industrial Lubrication and Tribology | Year: 2014

Purpose - The aim of this work is to reveal the temperature rise characteristics of the new designed disc during a braking process. In underground coal mines, the highest temperature of the disc brake used for inclined downward belt conveyors should be 150 to prevent gas explosion during a braking process. To meet the requirements, a new type of disc was designed. Design/methodology/approach - By using ANSYS software, the disc surface and interior temperature rise variations, effect of braking time and running speed on temperature rise are analyzed numerically. Findings - The results show that the new designed disc can meet the coal mines' requirements well, during the braking process the disc surface temperature increases at first and then decreases, there is an obvious temperature gradient in the axial direction; when running speed increases to two times of the rated one, the highest temperature nearly reaches 150; and a prolonged braking time can decrease the highest temperature effectively. Research limitations/implications - It indicates that the disc brake should act as earlier as possible to slow down the belt conveyor when overspeed occurs; and when the running speed increases to two times of the rated one, the braking time must be prolonged to prevent gas explosion. Originality/value - Research findings of this paper provides theoretical basis for the practical applications of the disc brake used for inclined downward belt conveyor. © Emerald Group Publishing Limited. Source


Dong H.-M.,China University of Mining and Technology
Wuli Xuebao/Acta Physica Sinica | Year: 2013

In this paper, we present a detailed theoretical study of nonlinear terahertz optical properties of graphene in the presence of electric field and terahertz radiation field. The optical current is computed and investigated on the basis of quantum theory and semi-classical Boltzmann equations. It shows a large nonlinear terahertz response and the nonlinearity becomes larger with increasing electric field or decreasing terahertz frequencies. Moreover, it is found that the optical nonlinearity can be modified and controlled by electric fields. © 2013 Chinese Physical Society. Source


Dong H.-M.,China University of Mining and Technology
Wuli Xuebao/Acta Physica Sinica | Year: 2013

The two-dimensional, single-layer MoS2 with a direct band-gap of 1.8 eV, which makes it very suitable for nanoelectronic applications, such as field-effect transistors, has aroused great interest because of its distinctive electronic, optical, and catalytic properties. In this paper, we present a detailed theoretical study of the electronic transport property of single-layer MoS2 on the basis of the usual momentum-balance equation. We obtain the analytical electric mobility at low temperature. It shows that the electric mobility of MoS2 is linear with respect to substrate dielectric constant squared and the rate between the electron density and charged impurity density at low temperature. It is found that by using relatively high dielectric constant materials as substrates, reducing impurity densities and increasing carrier densities high mobilities in MoS2-substrate wafer systems can be achieved. © 2013 Chinese Physical Society. Source


Zhang X.,Tsinghua University | Liang P.,Tsinghua University | Shi J.,Tsinghua University | Shi J.,China University of Mining and Technology | And 2 more authors.
Bioresource Technology | Year: 2013

A shorter start-up time and highly negative anode potentials are needed to improve single-chamber air-cathode microbial fuel cells (MFCs). Using a glass fiber separator reduced the start-up time from 10. d to 8. d at 20 °C, and from 4. d to 2. d at 30 °C, and enhanced coulombic efficiency (CE) from <60% to 89% (20 °C) and 87% (30 °C). Separators also reduced anode potentials by 20-190. mV, charge transfer resistances by 76% (20 °C) and 19% (30 °C), and increased CV peak currents by 24% (20 °C) and 8% (30 °C) and the potential range for redox activity (-0.55 to 0.10. mV vs. -0.49 to -0.24. mV at 20 °C). Using a glass fiber separator in an air-cathode MFC, combined with inoculation at a mesophilic temperature, are excellent strategies to shorten start-up time and to enhance anode performance and CE. © 2012 Elsevier Ltd. Source


Yan X.,China University of Mining and Technology | Li X.,China University of Petroleum - East China | Yan Z.,China University of Petroleum - East China | Komarneni S.,Pennsylvania State University
Applied Surface Science | Year: 2014

Three porous carbons were prepared by direct carbonization of HKUST-1, MOF-5 and Al-PCP without additional carbon precursors. The carbon samples obtained by carbonization at 1073 K were characterized by XRD, TEM and N 2 physisorption techniques followed by testing for electrochemical performance. The BET surface areas of the three carbons were in the range of 50-1103 m2/g. As electrode materials for supercapacitor, the MOF-5 and Al-PCP derived carbons displayed the ideal capacitor behavior, whereas the HKUST-1 derived carbon showed poor capacitive behavior at various sweep rates and current densities. Among those carbon samples, Al-PCP derived carbons exhibited highest specific capacitance (232.8 F/g) in 30% KOH solution at the current density of 100 mA/g. © 2014 Elsevier B.V. Source


Wang Y.,China University of Mining and Technology
Advanced Materials Research | Year: 2010

Since the early 1980s, great progress has been made in microbubble column flotation technology. As one of the important mineral processing methods, the application and development of this technology in China are summarized in this paper from four respects. Firstly, a patented cyclonestatic microbubble separation method was proposed to overcome the notable problems mentioned in the previous flotation columns. Secondly, microbuble column flotation was introduced to separate the high ash as well hard-to-separate coal slime generated from dense medium processes. The characteristics of the microbubble column, and the flotation process for fine coal and the high ash coal separation was analyzed. Thirdly, the application of microbubble column flotation in China was detailed introduced, especially the characteristics of series microbubble column flotation equipment, and efficient column type coal slime separation crafts were discussed. The application of microbubble column flotation particularly in low ash content coal preparation, and discarded coal slime processing technology were presented. Finally, microbubble column flotation has been extended to non-coal mineral processing, such as magnetite concentrate upgrading (concentration iron and removing silicon), sulfide copper mine separation, white tungsten flotation, etc., the related research was briefly introduced in this paper as well. © (2010) Trans Tech Publications. Source


Xu D.,China University of Mining and Technology
Procedia Engineering | Year: 2011

In recent years, the accidents of the groundwater inrush caused by the fault reactivation from coal seam floors have been increasing in groundwater-related coalmine accidents in China. Such groundwater inrush accidents have not been prevented effectively, because the mechanism of the groundwater inrush caused by the fault reactivation from coal seam floors has not been clearly recognized. In this paper, there was a new knowledge of the groundwater inrush caused by the fault reactivation from coal seam floors in the domain of prevention and cure water disaster in coalmines firstly, based on the review of the fault reactivation concept in different domains. Then the advances in the research on mechanisms of the groundwater inrush caused by fault reactivation in coalmines were expounded and research findings of the groundwater inrush caused by the fault reactivation with each view were summarized. In the end, the mechanisms of the groundwater inrush caused by the fault reactivation have been clearly recognized on the basis of influential factors of the groundwater inrush caused by the fault reactivation. © 2011 Published by Elsevier Ltd. Source


Zhang J.,China University of Mining and Technology
Procedia Engineering | Year: 2011

In the assessment of mine gas prevention and control system, how to determine the weight of every main influence factor is a significant problem. In order to construct the mine gas prevention and control system sufficiently and reasonably, it is necessary to study the assessment indexes of the mine gas prevention and control system with the method of analytic hierarchy process, and determine the weight of each index, in the meantime, base the assessment on the quantization result of indexes. The study result shows that the main factors in the mine gas prevention and control system are gas monitor, gas outburst, ventilation condition and gas drainage. The weight value of each factor is determined through the method of analytic hierarchy process. The analysis results calculated accord with the practical situation, thus providing the direction for the survey of the assessment of the mine gas prevention and control system. © 2011 Published by Elsevier Ltd. Source


Sun Y.,China University of Mining and Technology | Sun Y.,Fudan University | Zhao D.,Fudan University | Ruan J.,Fudan University
Physica A: Statistical Mechanics and its Applications | Year: 2010

In this paper, the leader-following consensus problem of noise perturbed multi-agent systems with time-varying delays is investigated. We analyze two different cases of coupling topologies: fixed topology and switching topology. Based on the Lyapunov functional and combining with the linear matrix inequality (LMI) approach, it is analytically proved that the consensus could be achieved almost surely with the perturbation of noise and communication time delays. Furthermore, numerical examples are provided to illustrate the effectiveness of the theoretical results. The simulation results show that the speed of convergence in environments with relatively strong noise intensity is lower than that in environments with relatively weak noise intensity. © 2010 Elsevier B.V. All rights reserved. Source


Zhang Y.,China University of Mining and Technology | Tam H.,Hong Kong Baptist University
Journal of Mathematical Physics | Year: 2010

We introduce three kinds of column-vector Lie algebras L s(s=1,2,3). By making invertible linear transformations we get the corresponding three induced Lie algebras. According to the defined loop algebras L̃ s of the Lie algebras Ls(s=1,2,3), we establish three various isospectral problems. Then by applying Tu scheme, we obtain three different coupling integrable couplings of the Korteweg-de Vries (KdV) hierarchy and further reduce them to three kinds of explicit coupling integrable couplings of the KdV equation. One of the coupling integrable couplings of the KdV hierarchy of evolution equations possesses Hamiltonian structure obtained by using the quadratic-form identity and it is Liouville integrable. © 2010 American Institute of Physics. Source


Liu W.,China University of Mining and Technology | Wang Z.,Henan Institute of Science and Technology
Measurement Science and Technology | Year: 2010

Precision three-dimensional measurement of large-scale workpiece frequently involves the combination of several different types of measurement systems; they may be laser tracker, total station, laser scanner and portable coordinate measuring machines, etc. In order to provide optimization measuring results, a new method, called the isolated variable sub-system (IVSS), has been developed to deal with variable coupling that fully takes into account the uncertainty of each measurement individual system. The IVSS method is a combination of pattern search and singular value decomposition. It can effectively determine the optimized location and orientation of each measurement system and minimizes the coordinate combined uncertainty by multivariate statistics to the measured data. Intensive experimental studies have been made to check the validity of the proposed method; the results show that using this technology the measuring accuracy of coupled multiple measurement systems can be improved by about 49% and can accommodate missing data points from some of the measurement systems. © 2010 IOP Publishing Ltd. Source


Zhang Y.,China University of Mining and Technology | Tam H.,Hong Kong Baptist University
Journal of Mathematical Physics | Year: 2010

The first part in the paper reads that a three-dimensional Lie algebra is first introduced, whose corresponding loop algebra is constructed, for which isospectral problems are established. By employing zero curvature equations, a modified Kaup-Newell (mKN) soliton hierarchy of evolution equations is obtained. The corresponding hereditary operator and Hamiltonian structure are worked out, respectively. Then two types of enlarging semisimple Lie algebras isomorphic to the linear space R6 are followed to construct, one of them is a complex Lie algebra. Their corresponding loop algebras are also given so that two types of new isospectral problems are introduced to generate two kinds of integrable couplings of the above mKN hierarchy. The hereditary operators, Hamiltonian structures of the hierarchies are produced again, respectively. The exact computing formulas of the constant γ appearing in the trace identity and the variational identity are derived under the semisimple algebras. The second part of this paper is devoted to constructing two kinds of Lie algebras by using product of complex vectors, which are also isomorphic to the linear space R6. Then we make use of the corresponding loop algebras to produce two integrable hierarchies along with bi-Hamiltonian structures. From various aspects, we give some ways for constructing Lie algebras which have extensive applications in generating integrable Hamiltonian systems. © 2010 American Institute of Physics. Source


Xu R.F.,China University of Mining and Technology | Farrall A.J.,University of Kent | Young P.R.,University of Kent
IEEE Microwave and Wireless Components Letters | Year: 2014

This letter provides an approximate analysis of a slotted substrate integrated waveguide with periodic loading elements using the transverse resonance technique. The technique is used to design a travelling wave attenuator whereby pin diodes are capacitively coupled to the waveguide slot. By changing the bias, and therefore loading resistance, a very constant, variable attenuation is produced over the waveguide band. © 2013 IEEE. Source


Liu L.,China University of Mining and Technology | Yang Y.,Shandong University
Superlattices and Microstructures | Year: 2013

A polyol-based precursor route was developed to synthesize MnCo complex oxide with well-defined morphologies, in which ethylene glycol (EG) was treated with metal acetates in the presence of poly(vinyl-pyrrolidone) (PVP). By varying the reaction temperature, the as-obtained precursor was readily regulated its morphologies, which could vary from nanospheres to hierarchically stacked nanoplates. The initial molar ratio of Mn-acetate to Co-acetate in EG solution played a crucial role in determining the chemical composition of the nano/microstructured precursor. On the basis of the experimental results, a possible growth mechanism for the nanostructured precursor was proposed. MnCo2O4 and CoMn2O4 could be obtained from their precursors without changing the morphologies by a simple calcination procedure. The synthetic methodology appears to be general and promises to provide an entryway into other complex oxide materials with various nano/microstructures. As an example of potential applications, the as-obtained MnCo mixed oxide nano/microstructures were used as catalyst in CO oxidation, and the effect of the morphology and composition on catalytic activities was investigated. © 2012 Elsevier Ltd. All rights reserved. Source


Zhu S.,China University of Mining and Technology | Shen Y.,Huazhong University of Science and Technology
Neurocomputing | Year: 2013

This paper analyzes the robustness of global exponential stability of delayed recurrent neural networks (DRNNs) subject to parameter uncertainty in connection weight matrices. Given a globally exponentially stable DRNNs, the problem to be addressed herein is how much parameter uncertainty in the connection weight matrices that the neural network can remain to be globally exponentially stable. We characterize the upper bounds of the parameter uncertainty for the DRNNs to sustain global exponential stability. The upper bounds of parameter uncertainty intensity are characterized by using transcendental equations. Moreover, we prove theoretically that, for globally exponentially stable DRNNs, if additive parameter uncertainties in connection weight matrices are smaller than the derived supper bounds arrived at here, then the perturbed DRNNs are guaranteed to also be globally exponentially stable. A numerical example is provided to illustrate the theoretical results. © 2013 Elsevier B.V. Source


Zhu S.,China University of Mining and Technology | Shen Y.,Huazhong University of Science and Technology
Neurocomputing | Year: 2013

This paper analyzes the robustness of global exponential stability of recurrent neural networks subject to parameter uncertainty in connection weight matrix. Given a globally exponentially stable recurrent neural network, the problem to be addressed herein is how much parameter uncertainty in the connection weight matrix that the neural network can remain to be globally exponentially stable. We characterize the upper bounds of the parameter uncertainty for the recurrent neural networks to sustain global exponential stability. A numerical example is provided to illustrate the theoretical result. © 2012 Elsevier B.V. Source


Li Y.,China University of Mining and Technology
International Journal of Mining, Reclamation and Environment | Year: 2016

The groundwater loss is one of the primary issues for environmental destruction. Underground longwall mining methods can cause rapid subsidence of the overburden strata. Especially in shallow coal seam mining. Since the subsidence through the overburden to ground surface, the groundwater may be affected and drawdown into the lower levels above the longwall panels. This paper analysed the potential impact of longwall mining on groundwater over thin overburden. Four water wells were drilled down to the proposed deformation zone above two longwall panels to record the different water levels’ variations throughout the mining period. A numerical groundwater flow model (GGU-SS-FLOW3D) was performed to predict the water levels in the periods of pre- and post-mining conditions. To set-up model, local mining conditions and regional geology characteristics were ascertained in this study. The measurement data from the four water wells were adopted to calibrate the flow3D model. The field measurement and GGU-SS-FLOW3D model can help to better understand the variation of the groundwater system related to the ground subsidence from longwall mining over thin overburden. © 2016 Taylor & Francis. Source


Wen M.,China University of Mining and Technology
Advanced Materials Research | Year: 2012

Studying on the characteristics of the overlying strata movement in high inclined coal seam, the similar material is applied in the simulation model which was built based on the similar material simulation theory and high inclined seam geological condition of Dongbaowei coal mine. The picture and displacement of overlying strata were obtained from the similar material simulation. As a result, the characteristics of the fracture and movement of overlying strata above the full mechanized working face in high inclined seam. This paper proposes some support measures to improve the safety of the working face. These provide significance theoretical guidance and reference value for other working face in high inclined seam. © (2012) Trans Tech Publications, Switzerland. Source


Du X.L.,China University of Mining and Technology
Advanced Materials Research | Year: 2014

The material failure induced coal bump and structure failure induced coal bump were paid attention to in this paper. Mechanism of coal mining and stowing with upper entry for preventing coal bump was analyzed. The mechanism of mining with upper entry for preventing material failure induced coal bump is that the stowing material can recover the integrity of the cracked roof, and for preventing structure failure induced coal bump is that water infusion to the roof could release the energy in the roof, and the backfilling could support the roof, both of them could change the stress condition of the roof. It hopes that coal mining and stowing with upper entry for preventing coal bump is a rational way to realize safety mining, but there still are some questions should be the further studied. © (2014) Trans Tech Publications, Switzerland. Source


Jiang J.-H.,Hohai University | Yuan Y.-S.,China University of Mining and Technology
Construction and Building Materials | Year: 2013

A long-term test on the steel corrosion in concrete was conducted under the sheltered conditions of a natural climate environment. A synchronous test under the sheltered and unsheltered conditions was performed to determine the microenvironment response and steel corrosion in concrete. The effect of environmental climate on the steel corrosion rate in concrete was further determined. The results show that the steel corrosion rate in concrete fluctuates and is time-dependent under natural climatic conditions. The changes of environmental conditions in the concrete microenvironment are less than those in a natural climate environment, particularly relative humidity. The steel corrosion rate in concrete is directly affected by the microenvironment of concrete, which depends on the random fluctuations of natural climate. Temperature is the primary climatic factor that affects the steel corrosion rate in concrete under an atmospheric environment. The pore water saturation of concrete is also a key factor that causes the differences between the steel corrosion rates in concrete under sheltered and unsheltered conditions. A prediction strategy for the steel corrosion rate in concrete under natural climate is proposed based on the effects of environment on the corrosion rate as well as on the responses of the concrete microenvironment. © 2013 Elsevier Ltd. All rights reserved. Source


Fernao Pires V.,Polytechnic Institute of Setubal | Fernao Pires V.,Center for Innovation in Electric and Energy Engineering | Martins J.F.,New University of Lisbon | Hao C.,China University of Mining and Technology
Solar Energy | Year: 2012

A fast and robust control strategy for a multilevel inverter in grid-connected photovoltaic system is presented. The multilevel inverter is based on a dual two-level inverter topology. There are two isolated PV generators that feeding each bridge inverter. The output of each inverter is connected to a three-phase transformer. The active and reactive powers flowing into the grid are controlled by a sliding mode algorithm. An alfa-beta space vector modulator is also used. The inverters DC voltages are also controller by a sliding mode controller. In this way, a fast and robust system controller is obtained. Several test results are presented in order to verify the effectiveness of the proposed system controller. © 2012 Elsevier Ltd. Source


Ruo-Qiang F.,Nanjing Southeast University | Ruo-Qiang F.,China University of Mining and Technology | Bin Y.,China United Engineering Corporation | Jihong Y.,Nanjing Southeast University
Journal of Constructional Steel Research | Year: 2013

A cable-braced grid shell is a new type of single-layer latticed shell suitable for glass roofs. Compared with traditional single-layer latticed shells, this new type of shell has a unique mesh shape, mesh form and surface shape. The lamella cylinder cable-braced grid shell is the single-layer latticed structure, and therefore, stability is a key design factor. These shells are also sensitive to initial imperfections, and thus, the influence of initial imperfections on stability should be considered. Therefore, in this paper, a lamella cylinder cable-braced grid shell with imperfections is used to develop formulas to describe the buckling load based on the continuum analogy. The major contributions of this paper include the formula for the linear buckling load of a lamella cylinder cable-braced grid shell with imperfections, which is deduced based on the continuum analogy. Then, the equivalent rigidity for a lamella mesh is determined. Last, the formula for the linear buckling load is verified by numerical examples, the errors are analyzed, and a corresponding correction factor is provided. © 2013 Elsevier Ltd. Source


Jiang X.,China University of Mining and Technology
Proceedings of the 5th IEEE International Conference on Electric Utility Deregulation, Restructuring and Power Technologies, DRPT 2015 | Year: 2015

In allusion to current circulation through the switch and the corresponding diode rectifier bridge in certain conditions leading to other cascaded diode rectifier bridges withstand the full supply voltage in traditional cascaded diode H-bridge multi-level Rectifier, a novel cascade diode H-bridge multi-level structure is proposed. Not needing power frequency phase-shifting transformer, the proposed topology is composed of cascaded H-bridge diode rectifier and boost circuit modular units, by which the high power factor rectify, the output of stabilized voltage of cascaded modular units and voltage-sharing control can be implemented. The basic working principle of the proposed topology, mathematical modeling and phase diagram of the circuit and its steady state characteristics are discussed, and corresponding control strategy is given. The feasibility of the proposed topology and control strategy is validated by simulation results and experimental results. © 2015 IEEE. Source


Cai X.,Chinese University of Hong Kong | Feng Y.,China University of Mining and Technology | Li Y.,Nankai University | Shi D.,Nankai University
International Journal of Production Research | Year: 2013

We study the optimal selling price of a deteriorating product under a deterministic situation in a finite time horizon where the time horizon is either known or unknown. Inventory holding cost is expressed as a quadratic function of the current inventory level. Given a known time horizon, we develop a model by considering the deterioration dynamics of the product, and show its equivalence to a generalised optimal control problem of a linear quadratic form, i.e. an optimal dynamic tracking problem with constraints on the control variable. An optimal pricing policy is derived based on the maximum value principle. The control policy takes a state feedback form; it exhibits a closed-loop relationship between the optimal selling price (control variable) and the optimal inventory level (state variable). Given an unknown time horizon, an optimal pricing policy is derived through a similar approach when the initial inventory level meets certain conditions. Numerical situations are conducted to illustrate the effectiveness of the derived price control policies. Some interesting managerial insights are discussed. © 2013 Taylor & Francis Group, LLC. Source


Gong W.L.,State Key Laboratory for GeoMechanics and Deep Underground Engineering | Gong W.L.,China University of Mining and Technology | Gong Y.X.,South-Central University for Nationalities | Long A.F.,South-Central University for Nationalities
Infrared Physics and Technology | Year: 2013

This paper presents a morphological study of the low-resolution and noisy thermogram obtained in the laboratory excavation experiment on the large-scale geological model of man-made horizontally stratified rocks. The developed new image processing algorithm consists of image subtraction, median filter, low-pass alternating-morphological filter, and multi-scale morphological enhancement filter. These filters were used sequentially to process the detected infrared images. In comparison with the old algorithm for thermogram process, the excavation border with changed stress and changed brightness can be distinguished more clearly in the new thermogram sequences. The new algorithm is possible to be applied in processing other low-resolution and noisy thermogram, and the analysis results in this paper are helpful for understanding the pure elastic, the stationary frictional effect and the dynamic frictional effect at the excavation processes. © 2012 Published by Elsevier B.V. All rights reserved. Source


Du X.L.,China University of Mining and Technology
Advanced Materials Research | Year: 2014

Mining with stowing is an environmentally friendly way for coal mine, and stowing material is the key to realize environmental protection and harmonious development. This paper focused on the stowing materials, and evaluation for the stowing material would be made. Stowing materials could be sorted as chemical reaction material, solid refuses from coal mine and natural material for stowing. In the light of the cost and sustainable application of the stowing material, we suggest solid refuses from coal mine are the first choice as stowing materials for now.Urban pollutants could be a good kind of stowing materials, but further study should be made for this material. Also the stowing materials should be as cheap and environmentally friendly as they could. © (2014) Trans Tech Publications, Switzerland. Source


Yang X.-J.,China University of Mining and Technology | Baleanu D.,Cankaya University | Baleanu D.,King Abdulaziz University | Baleanu D.,Romanian Space Science Institute | And 2 more authors.
Romanian Journal of Physics | Year: 2014

In this work, the local fractional variational iteration method is employed to handle the sub-diffusion and wave equations and the analytical solutions are obtained. The present method is efficient and implicit to investigate the differential equations with the local fractional derivatives. Source


Zhang Y.,North China University of Water Conservancy and Electric Power | Baleanu D.,Cankaya University | Baleanu D.,Romanian Space Science Institute | Yang X.,China University of Mining and Technology
Entropy | Year: 2014

In this paper, based on fixed entropy, the adiabatic equation of state in fractal flow is discussed. The local fractional wave equation for the velocity potential is also obtained by using the non-differential perturbations for the pressure and density of fractal hydrodynamics. © 2014 by the authors. Source


Luo Y.B.,China University of Mining and Technology
Advanced Materials Research | Year: 2014

In this paper, the regional distribution of six hazardous elements (S, Cl, Hg, Se, F and As) in Late Permian coal in southern Sichuan, China, is discussed based on the differences of the sedimentary environment. Based on the different sedimentary facies, the sedimentary environment of the southern Sichuan coal basin can be divided into three areas: fluvial or swamp (Area II), tidal flat (Area III) and marine carbonate platform (Area I). The content of F, Hg, Cl and Se is lower in the entire southern Sichuan coal field as compared to the average value of these hazardous elements in Chinese coal. The element S is concentrated in coal in Area III and the upper part of Area II. The element As is concentrated in coal in the upper part of Area II. © (2014) Trans Tech Publications, Switzerland. Source


Wen S.,Henan University | Yang S.-Q.,China University of Mining and Technology
Yantu Lixue/Rock and Soil Mechanics | Year: 2011

In many practical situations, for instance, in jointed rock mass, linear M-C yield criterion may not be justified and a nonlinear Hoek-Brown yield criterion would be more appropriate, so it is necessary to attempt to calculate deformation of tunnel by the criterion. The surrounding rock is divided into three zones: elastic zone, strain softening zone and plastic flow zone. Theoretical derivation on deformation is carried out by Hoek-Brown criterion and non-associated flow rule. Parameters of surrounding rock in strain softening zone are variable and they depend on the plastic deformation of this zone, so it's difficult to derive the analytical solution for stress in this zone. Runge-Kutta method is used to carry out numerical calculation and the radiuses of strain softening zone and plastic flow zone are calculated. Finally, the deformations of tunnel are calculated. It is demonstrated by an example that the results calculated by the method in this paper and Carranza-Torres's method are almost the same when strain softening zone and plastic flow zone are not be considered. Furthermore, it is demonstrated by the other example that dilation angle affects deformation more severely when in-situ stress becomes greater. Source


Han X.,China University of Mining and Technology
Naukovyi Visnyk Natsionalnoho Hirnychoho Universytetu | Year: 2016

Purpose: The study of the influence of vibration load on elastohydrodynamic lubrication of textured surface by numerical calculation. Methodology: Based on the elastohydrodynamic lubrication model of the textured surface subjected to vibration and impact load and its solution, a series of phenomena were discussed. Findings: The research showed that the instantaneous oil film of the textured surface has a similarity of the thickness time variance and similarity of pressure time variance in a vibration load excitation cycle. The texture in the low-pressure region has little effect on the thickness and pressure distribution of the oil film, but the one in the high-pressure region has an obvious influence on the thickness and pressure distribution of the oil film and its dynamic pressure effect is significant. Originality: In the whole calculation region, the number of the pressure peaks is related to the one of the texture in the high pressure region. The study showed that the maximum pressure and the average friction coefficient of the oil film increases and the minimum film thickness decreases with the increase of the load amplitude. The maximum pressure, minimum thickness and the average friction coefficient of the oil film decrease with the increase of the vibration frequency. Practical value: Research results are of importance for the design of the texture of the surface bearing vibration load. © Xiang Han, 2016. Source


Ma C.,Nanjing Forestry University | Zhu H.,China University of Mining and Technology
Tribology International | Year: 2011

The influence of surface texture in the form of the elliptical-shape dimples with various depths, diameters, area ratios and different operation parameters on friction coefficient has been investigated under conditions of hydrodynamic lubrication. The results show that, the larger the optimum diameter, the larger the corresponding optimum depth becomes; the optimum area ratio is not bound up with the texture parameters and operating parameters; the optimum depth increased while the optimum diameter decreased as the velocity became larger and the load became smaller. A model for the optimum design of textured surface was built and then validated by the experiments. © 2011 Elsevier Ltd. All rights reserved. Source


Liu Z.,China University of Mining and Technology
Zhongnan Daxue Xuebao (Ziran Kexue Ban)/Journal of Central South University (Science and Technology) | Year: 2014

To study the subgrade humidity field distribution with different compaction models, 4 subgrade numerical models with different compaction conditions were established. Through analyzing tow-dimensional infiltration rainfall test results, the influences of different compaction models on the humidity disturbed zone distributions, the extended distances, the subgrade humidity values and gradients were examined. The mechanisms behind these findings were explained. The results show that humidity disturbed zone appears after rainfall infiltration and it can be divided into front and back zone. The characteristics of back zone include the larger humidity and the smaller gradient, while the front zone just has the opposite conditions. The extended distances and humidity values of the disturbed zone decrease linearly with the increase of subgrade compaction degree. The humidity gradient of the front zone increases linearly with the increase of subgrade compaction degree. Since the vertical component of the rainfall infiltrating velocity vector is considerably larger than the horizontal one, the subgrade humidity of a deep layer decreases significantly with the increase of upper subgrade compaction in unsaturated disturbed zones, which is also affected by the composition of subgrade compaction zones. Source


Wu X.,China University of Mining and Technology
International Journal of Advancements in Computing Technology | Year: 2012

Extreme learning machine (ELM) is an efficient algorithm for single-hidden layer feedforward neural networks (SLFNs), which can produce good generalization performance in most cases and learn thousands of times faster than conventional popular algorithms. However, the performance of ELM is sensitive to the initialized number of hidden neurons. In some traditional methods, the number of hidden nodes is gradually increased by a fixed interval to select the nearly optimal number of nodes for ELM, whereas these methods are of a little bit of complexity and quite time-consuming. This paper proposes an improved ELM based on the affinity propagation clustering, which does not need to define the number of hidden nodes in advance manually and randomly. The proposed algorithm automatically determines the number of hidden nodes for different data sets. Empirical study of AP-based ELM on several commonly used classification benchmark problems shows that it achieves better performance compared with the standard ELM. Source


Guo S.-D.,China University of Mining and Technology
Journal of Magnetism and Magnetic Materials | Year: 2016

Binary transition-metal pnictides and chalcogenides half-metallic ferromagnetic materials with zincblende structure, being compatible with current semiconductor technology, can be used to make high-performance spintronic devices. Here, we investigate electronic structures and magnetic properties of composite structure ((CrX)2/(YX)2 (X=As, Sb; Se, Te and Y=Ga; Zn) superlattices) of zincblende half-metallic ferromagnetism and semiconductor by using Tran and Blaha's modified Becke and Johnson (mBJ) exchange potential. Calculated results show that they all are half-metallic ferromagnets with both generalized gradient approximation (GGA) and mBJ, and the total magnetic moment per formula unit follows a Slater-Pauling-like "rule of 8". The key half-metallic gaps by using mBJ are enhanced with respect to GGA results, which is because mBJ makes the occupied minority-spin p-bands move toward lower energy, but toward higher energy for empty minority-spin Cr-d bands. When the spin-orbit coupling (SOC) is included, the spin polarization deviates from 100%, and a most reduced polarization of 98.3% for (CrSb)2/(GaSb)2, which indicates that SOC has small effects, of the order of 1%, in the considered four kinds of superlattice. © 2016 Elsevier B.V. All rights reserved. Source


Wu W.,University of Tennessee at Knoxville | Wu W.,Oak Ridge National Laboratory | Qiao H.,McMaster University | An K.,Oak Ridge National Laboratory | And 4 more authors.
International Journal of Plasticity | Year: 2014

In the present research, the real-time in-situ neutron diffraction measurements under a continuous-loading condition and elastic-viscoplastic self-consistent (EVPSC) polycrystal modeling were employed to study the deformation dynamics and the effect of the deformation history on plastic deformation in a wrought magnesium alloy. The experimental results reveal that pre-deformation delays the activation of the tensile twinning during the subsequent compression, mainly resulting from the residual strains. Detwinning does not occur until the applied stress exceeds the tensile yield strength during the reverse loading. It is believed that the grain rotation plays an important role in the elastic region during the reverse loading. The EVPSC model, which has been recently updated by implementing the twinning and detwinning model, was employed to characterize the deformation mechanism during the strain-path changes. The simulation result predicts well the experimental observation from the real-time in-situ neutron diffraction measurements. The present study provides a new insight of the nature of deformation mechanisms in a hexagonal close-packed (HCP) structured polycrystalline wrought magnesium alloy, which has significant implications for future work on studying the deformation mechanisms of HCP-structured materials. © 2014 Elsevier Ltd. All rights reserved. Source


Xiao H.,Hefei University of Technology | Sun J.,Hefei University of Technology | Chen P.,China University of Mining and Technology
Journal of Hazardous Materials | Year: 2014

An experimental and numerical study of dynamics of premixed hydrogen/air flame in a closed explosion vessel is described. High-speed shlieren cinematography and pressure recording are used to elucidate the dynamics of the combustion process in the experiment. A dynamically thickened flame model associated with a detailed reaction mechanism is employed in the numerical simulation to examine the flame-flow interaction and effect of wall friction on the flame dynamics. The shlieren photographs show that the flame develops into a distorted tulip shape after a well-pronounced classical tulip front has been formed. The experimental results reveal that the distorted tulip flame disappears with the primary tulip cusp and the distortions merging into each other, and then a classical tulip is repeated. The combustion dynamics is reasonably reproduced in the numerical simulations, including the variations in flame shape and position, pressure build-up and periodically oscillating behavior. It is found that both the tulip and distorted tulip flames can be created in the simulation with free-slip boundary condition at the walls of the vessel and behave in a manner quite close to that in the experiments. This means that the wall friction could be unimportant for the tulip and distorted tulip formation although the boundary layer formed along the sidewalls has an influence to a certain extent on the flame behavior near the sidewalls. The distorted tulip flame is also observed to be produced in the absence of vortex flow in the numerical simulations. The TF model with a detailed chemical scheme is reliable for investigating the dynamics of distorted tulip flame propagation and its underlying mechanism. © 2014 Elsevier B.V. Source


Hong L.,China University of Mining and Technology
Advanced Materials Research | Year: 2014

It is proved that in LOS detection,"moment of inertia based method" and "PCA based method" are in fact equivalent. Then the method is abstractly redefined as "distance variance extremum based method". © (2014) Trans Tech Publications, Switzerland. Source


Gu M.,Nanjing University | Wang J.,China University of Mining and Technology | Wu X.S.,Nanjing University | Zhang G.P.,Indiana State University
Journal of Physical Chemistry C | Year: 2012

Intrinsic defects are crucial to the electronic and magnetic properties in the SrTiO3/LaAlO3 (STO/LAO) system. With the first-principles simulation, we construct a formation energy phase diagram of different intrinsic defects on STO surfaces. The three most stable surface defects are Al-substitution of Ti, La-substitution of Sr, and the oxygen vacancy at TiO2 surface. On STO, multiple defects are possible. When these defective surfaces form interfaces with LAO, the Al substitution of Ti atom is highly favored energetically. Defects of this type can change the n-type interface into p-type. The polar STO/LAO interface is found to effectively compensate the internal electric field, leading to a wider band gap in the system with both n- and p-type interfaces. © 2012 American Chemical Society. Source


Guo S.-D.,China University of Mining and Technology
Journal of Magnetism and Magnetic Materials | Year: 2015

Objective: Half-metallic ferromagnetism plays a major role in high-performance spintronic applications due to its 100% spin-polarization. So, it is very necessary to search better half-metallic ferromagnets with large magnetic moment and being compatible with current semiconductor technology. Methods: We study cubic Eu4O3N on the basis of state-of-the-art first-principles calculations by using generalized gradient approximation plus U method. Results: It is found that the Eu4O3N is a half-metallic ferromagnet with a half-metallic gap of 376 meV and the large Eu ion magnetic moment up to about 7 μB. The structural and ferromagnetic stability are proved by mechanical stability criterion and magnetic energy differences, respectively. The half-metallic properties are also stable against the isotropic strain, volume-conservative tetragonal strain and rhombohedral distortion. For the choice of U between 4 and 8 eV, the Eu4O3N still is half-metallic ferromagnet. Conclusion: This provides a new idea for searching new half-metallic ferromagnetism by f electrons. Practical implications: If the Eu4O3N was experimentally synthesized with half-metallic properties, it should be used to design high-performance spintronic devices. © 2015 Elsevier B.V. All rights reserved. Source


Guo S.-D.,China University of Mining and Technology
European Physical Journal B | Year: 2015

We investigate the electronic structures and magnetic properties of the ferrimagnetic double-perovskites Sr2XReO6 (X = Cr, Mn, Fe, Ni) by using Tran and Blaha’s modified Becke and Johnson exchange potential. The calculated results show that Sr2XReO6 (X = Cr, Fe) are half-metals, and Sr2XReO6 (X = Mn, Ni) are insulators, which is in accordance with the experimental results. By using the ionic picture, we explain the trend in the density of states and total magnetic moment with X changing from Cr to Ni. We find that the insulating property is associated with X2 +, while the metallic character is associated with X3 +. The Re t2g splitting in the minority channel leads to insulativity of Sr2XReO6 (X = Mn, Ni), and the Re t2g splitting of Sr2MnReO6 is caused by lattice distortion, while Sr2NiReO6’s splitting is due to the heavier atomic mass of Ni. When spin-orbit coupling is included, the spin polarization of Sr2XReO6 (X = Cr, Fe) drifts off 100%, and the related gaps of Sr2XReO6 (X = Mn, Ni) become narrow. The spin-orbit coupling results in a significant increase in the total magnetic moment due to an unquenched Re orbital moment. Our calculated energy band structures show that Sr2MnReO6 is a spin gapless semiconductor, which can realize fully polarized spin-down electrons and spin-up holes. © 2015, EDP Sciences, SIF, Springer-Verlag Berlin Heidelberg. Source


Sun J.-P.,China University of Mining and Technology
Meitan Xuebao/Journal of the China Coal Society | Year: 2010

Introduced the condition of safety monitoring and communication technologies at the coal mine from safety monitoring and control system, underground personnel locating system, coal output remote monitoring system, whole mine mobile communication system and unattended remote monitoring and control system. On this basis looked into the prospect of technologies development of safety monitoring and communication in the coal mine, such as: technology of mining internet of things, integration communications technology and system of coal mine, remote control technology of manless working face and coal-rock interface recognition technology, accurate personnel positioning technology and system at the underground coal mine, severe disaster early-warning technologies for gas, fire and rock burst based on safety monitoring and control system, coal mine safety production management information system based on 3D GIS, technology and equipment of life-detecting in the underground coal mine, intrinsic safety communication technologies of wireless communication and optical fiber, sensor arrangement method of no-blind area, rescue robot in the underground coal mine, etc. Source


Chen H.,China University of Mining and Technology | Gu J.J.,Dalhousie University
IEEE/ASME Transactions on Mechatronics | Year: 2010

This paper presents two three-phase switched reluctance machine systems. One is the dual motors drive for the electric locomotive traction; the other is the variable-speed generator system for wind power applications. The principles of the switched reluctance machine system operated at four quadrants, the scheme of the symmetrical traction at quadrant I and quadrant III, and the scheme of the symmetrical regenerative braking control at quadrant II and quadrant IV, are given. The transient phase current analysis and the energy analysis of the switched reluctance machine system at the operational state of braking or generating are evaluated, and the rotor position and the peak value of the phase current at three different conditions are given. The closed-loop rotor speed control of the main motor, synchronization of the rotor speed, and balance distribution of loads between the main motor and the subordinate motor have been implemented by the fuzzy logic algorithm. The closed-loop output power control of the switched reluctance wind power generator system implemented by regulating the turn-on angle of the main switches with fuzzy logic algorithm and fixed turn-off angle of the main switches is also presented. The major components of the two prototypes are explained in detail. The experimental results of the dual 7.5-kW three-phase 6/4 structure switched reluctance motors (SRMs) parallel drive system prototype are included. It is shown that the maximum difference in the output torque of the two motors at the same given rotor speeds is within 10.00 and the maximum difference in the practical rotor speed of the two motors is within 5.00. The tested results of three-phase 12/8 structure switched reluctance variable-speed wind power generator system show that the error of the closed-loop output power control is within 2.2, while the rotor speed range is close to the ratio of 1:3 with the low rotor speed 405 r/min. The average dc line current of the power converter can be utilized as a feedback signal for the actual output torque of SRM drive or a feedback signal for the actual output power of switched reluctance generator system. © 2006 IEEE. Source


Zhang Q.,Tongji University | Zhang Q.,China University of Mining and Technology | Zhang Q.,University of Arizona | Zhu H.,Tongji University | Zhang L.,University of Arizona
International Journal of Rock Mechanics and Mining Sciences | Year: 2013

To take account of the influence of the intermediate principle stress, Zhang and Zhu [1,2] proposed a three-dimensional (3D) version of the generalized Hoek-Brown strength criterion. The generalized Zhang-Zhu strength criterion is a true 3D version of the Hoek-Brown criterion, not only inheriting the advantages of the Hoek-Brown strength criterion, but predicts the same strength as the two-dimensional (2D) Hoek-Brown strength criterion at both triaxial compression and extension states. However, the failure surface of the generalized 3D Zhang-Zhu strength criterion is not smooth at either the triaxial compression or extension state and concave at the triaxial extension state, which may have problems with some stress paths and cause inconvenience for numerical applications. In this paper, the reason for the non-smoothness and non-convexity of the generalized 3D Zhang-Zhu strength criterion was first discussed by studying its Lode dependence. Then the criterion was modified by utilizing three different Lode dependences with characteristics of both smoothness and convexity to replace its Lode dependence. Finally the smoothness, convexity and prediction accuracy of the modified criteria were evaluated by applying them to analyze both intact rocks and jointed rock masses. The modified criteria not only keep the advantages of the generalized 3D Zhang-Zhu strength criterion, but solve the non-smoothness and non-convexity problem with no loss of accuracy for strength prediction. © 2012 Elsevier Ltd. Source


Zhang Y.,Henan Polytechnic University | Liu Q.,China University of Mining and Technology | Zhang Q.,Henan Polytechnic University | Lu Y.,Henan Polytechnic University
Applied Clay Science | Year: 2010

A series of highly filled natural rubber (NR) composites based on silane modified kaolin (SMK), precipitated silica (PS) and their mixed-compound additions (SMK + PS) were prepared by melt blending. The transmission electron microscopy (TEM) was employed to characterize the NR composites. The kaolinite particles were finely dispersed into the natural rubber matrix and arranged in parallel orientation. Compared to the pure NR, these highly filled NR/SMK composites exhibited outstanding mechanical properties, excellent gas barrier properties and much higher thermal stability. The gas barrier properties of NR composites with SMK and PS were much higher than those of NR/PS composites and better than those of NR/SMK. The nitrogen permeability of NR/SMK composites was decreased by 20-40% after filling with kaolin. The significant improvements in the mechanical properties, thermal stability and gas barrier properties may be attributed to the parallel kaolinite particles which restricted the free movement of rubber chains and retarded the diffusion of the gas molecules. Thus, the highly filled NR/SMK composites may be used to improve the air-tightness of rubber products. © 2010 Elsevier B.V. Source


Ma Q.,China University of Mining and Technology | Harpalani S.,Southern Illinois University Carbondale | Liu S.,Southern Illinois University Carbondale
International Journal of Coal Geology | Year: 2011

Significant changes occur in the absolute permeability of coalbed methane (CBM) reservoirs during primary depletion or enhanced recovery/CO2 sequestration operations. In order to project gas production, several analytical models have been developed to predict changes in coal permeability as a function of stress/porosity and sorption. Although these models are more transparent and less complicated than the coupled numerical models, there are differences between the various analytical models and there are several uncertainties. These are discussed briefly in this paper. A new model is then proposed, which is based on the volumetric balance between the bulk coal, and solid grains and pores, using the constant volume theory. It incorporates primarily the changes in grain and cleat volumes and is, therefore, different from the other models that lay heavy emphasis on the pore volume/cleat compressibility values. Finally, in order to demonstrate the simplicity of the proposed model, a history matching exercise is carried out using field data in order to compare the different models. The modeling results suggest that the agreement between the predicted permeability using the existing models and the one proposed here is very good. The merit of the proposed model is its simplicity, and the fact that all input parameters are easily measurable for any coal type with no uncertainties. © 2010 Elsevier B.V. Source


Wu L.-L.,China University of Mining and Technology | Nie J.-G.,Tsinghua University
Gongcheng Lixue/Engineering Mechanics | Year: 2010

The steel-concrete composite slab is becoming popular in the fields of building and bridge structures. Nevertheless, at present little study on the foundational performance of elastic stability of steel-concrete composite slab for all practical purposes is available, especially on its local buckling behavior. The maximal spacing of shear connectors (such as studs) is the most important factor to prevent the steel plate from local buckling before yielding, and it also makes steel plate and concrete slab behave as one. Based on model parameter analyses, the local buckling behavior of steel-concrete composite slab with simply supported edges in pure shear is studied by finite element methods. A calculating model steel plate with typical boundary is proposed to simulate the buckling performance of the steel plate surrounded by shear studs in the composite slab. The formula of maximal spacing of shear studs is deduced for the simply supported composite slab. The calculation result is slightly conservative. Source


Wu Q.,China University of Mining and Technology | Xu H.,Beijing Institute of Petrochemical Technology
Science China Earth Sciences | Year: 2014

The 3D geological modeling is the prerequisite and core foundation for Digital Mine. Although this new technology brings new opportunities and motivation for the mineral exploration industry, it still has many difficulties to be solved in this area. Based on the characteristics of mine data and the aim of Digital Mine construction, this paper introduces a theory including multi-source data coupling, multi-modeling methods integration, multi-resolution visualization and detection, and multidimensional data analysis and application. By analyzing problems such as the uncertainty in each step of the modeling process, we designed a novel modeling method that can be applied to the complex geological body modeling, mineral resource/reserve estimation, and the mining exploration engineering. Along with the process of mine exploration, development, and reclamation, 3D modeling undergoes the process of "construction-simulation-revision" during which the 3D model is able to be dynamically updated and gradually improved. Based on the result of practical utilization, it is proven that the methodology introduced by this paper can be used to build an effective 3D model by fully using the mining data under the control of spatial information quality evaluation. Our experiments show that such a 3D model can be used to evaluate the mine resource and provide the scientific evidence to improve mining efficiency during the various stages of evolvement process in mine. © 2013 Science China Press and Springer-Verlag Berlin Heidelberg. Source


Liang Z.,China University of Mining and Technology | Li Y.,City University of Hong Kong
IET Computer Vision | Year: 2010

Kernel-based learning methods have been widely used in various machine learning tasks such as dimensionality reduction, classification and regression. Because the performance of kernel-based learning methods depends on the selection of kernels, how to optimise kernel functions becomes an important issue in kernel-based learning methods. A novel formulation for automatically learning kernels over a linear combination of kernel functions in terms of discriminant criteria is proposed. One not only extracts features, but also carries out the selection of kernels when optimising the discriminant criteria. It is found that the proposed method is available for any discriminant criterion formulated in a pairwise manner as the objective function. Therefore the proposed method can provide a framework for optimising multiple kernel subspace analysis. Extensive experiments on UCI data sets, handwritten numerical characters, face images and gene data sets are implemented to demonstrate the effectiveness of the proposed method. © 2010 © The Institution of Engineering and Technology. Source


Zhua J.,CAS Institute of Remote Sensing Applications | Zhua J.,Shijiazhuang University of Economics | Shi J.,CAS Institute of Remote Sensing Applications | Wang Y.,China University of Mining and Technology
International Journal of Applied Earth Observation and Geoinformation | Year: 2012

In this work, an algorithm for automatic subpixel snow mapping was developed for Moderate Resolution Imaging Spectroradiometer (MODIS) data of the Qinghai-Tibet Plateau. The algorithm consists of two parts: cloud removal and snow mapping. An approach to remove cloud was presented and it was demonstrated to remove thick and thin clouds well from MODIS images. Multiple-endmember spectral mixture analysis was used in the subpixel snow mapping of the Qinghai-Tibet Plateau, and multiple indices (including the normalized difference vegetation index and normalized difference snow index) were introduced to automatically select the endmembers. Additionally, the combined use of typical and neighboring endmembers was introduced into the unmixing of mixed pixels. Finally, highly accurate snow-cover data of the Qinghai-Tibet Plateau obtained with this algorithm were stored in a spatiotemporal database. The results of the subpixel snow mapping were validated with Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) data recorded at the same time as corresponding MODIS data. According to the validation results, the correlation coefficients of the MODIS results versus the ASTER data exceed 0.9, and the root-mean-square errors are less than 0.2. © 2012 Elsevier B.V. Source


Cheng J.,West Virginia University | Yang S.,China University of Mining and Technology
Safety Science | Year: 2012

A mine's ventilation system is an important component of an underground mining system. It provides a sufficient quantity of air to maintain suitable working environment. Therefore, the status of mine ventilation should be tracked and monitored as a timely matter. Based on former findings and in-depth analysis of mine ventilation systems, a proper early warning model is proposed in this paper for such considerations to improve the mine ventilation safety. The model itself is comprised of two sub-models, and two data mining techniques are used to assist in building each sub-model. One is the optimal indexes selection model which applies the Rough Set theory (RS) to assist the selection of best ventilation indexes. The other is the risk evaluation model based on the Support Vector Machine (SVM) to classify the risk ranks for the mine ventilation system. Testing cases have been used to demonstrate the applicability of this integrated model. © 2011 Elsevier Ltd. Source


Wang X.-W.,China University of Mining and Technology
Meitan Xuebao/Journal of the China Coal Society | Year: 2013

By analysis of dynamics and kinematics of linear excitation force vibration machinery, it found that when vibration machinery swung in a small range, the movement could be considered as swaying around the fixed point. The position of the fixed point, which was determined by the inherent characteristics of machinery contracture, was related only to the gyroradius of the equipment and the distance from centroid to centrifugal force line. It was convenient to fix amplitude and the vibration direction at any point in the machine according to the amplitude of centroid and the coordination of the fixed point. By analyzing the movement of the machinery, it can be acknowledged that the vibration amplitude of the bed surface of each point is equal everywhere in the bed surface of the component, and that the component perpendicular to the surface is proportional to the imaginary vibration bed surface length as well as the throwing index. This provides the theoretical basis for design and application of linear excitation force vibration machinery. Source


Yang X.,China University of Mining and Technology | Aldrich C.,Curtin University Australia
International Journal of Mining Science and Technology | Year: 2013

Coal flotation is widely used to separate commercially valuable coal from the fine ore slurry, and is an industrial process with nonlinear, multivariable, time-varying and long time-delay characteristics. The online detection of ash content of products as the operation performance evaluation in the flotation system is extraordinarily difficult because of the low solid content and numerous micro-bubbles in the slurry. Moreover, it is time-consuming by manual analysis. Consequently, the optimal separation is not usually maintained. A novel technique, called the neuro-immune algorithm (NIA) inspired by the biological nervous and immune systems, is presented in this paper for predicting the ash content of clean coal and performing the optimizing control to the coal flotation system. The proposed algorithm integrates the deeply-studied artificial neural network (ANN) and the developing artificial immune system (AIS). A two-layer back-propagation network was constructed offline based on the historical process data under the best system situation, using five parameters: the flow and the density of raw slurry, the input flows of water, the kerosene and the GF oil, as the inputs and the ash content of clean coal as the output. The immune cell of AIS is made up of six parameters above as the antigen. The cytokine based clone selection algorithm is used to produce the relative antibody. The detailed computation procedures about the hybrid neuro-immune algorithm are minutely discussed. The ash content of clean coal was predicted by NIA using the practical process data s: (308.6 174.7 146.1 43.6 4.0 9.4), and the absolute difference between the actual and computed ash content values was 0.0967%. The optimizing control on NIA was simulated considering two different situations where the ash content of clean coal was controlled downward from 10.00% or upward from 9.20% predicted by ANN to the target value 9.50%. The results indicate that the target ash content and the value of controlling parameters are obtained after several control cycles. © 2013 Published by Elsevier B.V. on behalf of China University of Mining & Technology. Source


Wu R.-L.,China University of Mining and Technology
Meitan Xuebao/Journal of the China Coal Society | Year: 2013

Similar material physical simulation and numerical simulation and theoretical analysis were adopted to study the impact of key stratum on the scope of the "three zones" of gas pressure relief and migration in coal seam group mining. The results show that, whether there exists a key stratum within the overlying gas conductive fracture zone will obviously affect the scope of the "three zones" of gas pressure relief and extraction. In the same mining conditions, if there exists a key stratum within the fracture zone of overlying strata, the failure of the key stratum will lead to an uprush in the height of gas conductive fracture zone, which is higher than empirical formula result, and the gas conductive fracture zone height will reach the bottom of the upper key stratum. Gas pressure relief and desorption zone develops to the unbroken key stratum under which exist much bed separation space, and its maximum height reaches the bottom of the primary key stratum. Source


Liu X.R.,Xian Jiaotong University | Tian X.G.,Xian Jiaotong University | Lu T.J.,Xian Jiaotong University | Liang B.,China University of Mining and Technology
International Journal of Mechanical Sciences | Year: 2014

The dynamic responses and blast resistance of all-metallic sandwich plates with functionally graded close-celled aluminum foam cores are investigated using finite element simulations, and compared with those of ungraded single-layer sandwich plates. Upon validating the numerical approach using existing experimental data and introducing the present computational model, different graded sandwich plates under air blast loading are analyzed in terms of deformation and blast resistance. The effects of face-sheet arrangements and interfacial adhesion strength between different foam layers are quantified. The results demonstrate that relative to conventional ungraded plates subjected to identical air blast loading, the graded plates possess smaller central transverse deflection and superior blast resistance, with further improvement achievable by optimizing the foam core arrangement. The blast resistance of both graded and ungraded sandwich plates subjected to the constraint of equivalent mass is also explored. © 2014 Elsevier Ltd. Source


Liang Z.,China University of Mining and Technology | Li Y.,City University of Hong Kong
Pattern Recognition | Year: 2010

Dimensionality reduction has many applications in pattern recognition, machine learning and computer vision. In this paper, we develop a general regularization framework for dimensionality reduction by allowing the use of different functions in the cost function. This is especially important as we can achieve robustness in the presence of outliers. It is shown that optimizing the regularized cost function is equivalent to solving a nonlinear eigenvalue problem under certain conditions, which can be handled by the self-consistent field (SCF) iteration. Moreover, this regularization framework is applicable in unsupervised or supervised learning by defining the regularization term which provides some types of prior knowledge of projected samples or projected vectors. It is also noted that some linear projection methods can be obtained from this framework by choosing different functions and imposing different constraints. Finally, we show some applications of our framework by various data sets including handwritten characters, face images, UCI data, and gene expression data. © 2009 Elsevier Ltd. All rights reserved. Source


Jiang S.,Nanjing Southeast University | Zheng Y.,Nanjing Southeast University | Zhu H.,China University of Mining and Technology
Journal of Tribology | Year: 2010

A general contact stiffness model is proposed in this paper to study the contacts between rough surfaces of machined plane joints. The proposed model uses fractal geometry for surface topography description, elastic-plastic deformation of contacting asperities, and size-dependent contact stiffness of micro contacts, where the contact stiffness is derived from Hertz contact theory. Three cast iron specimens are produced from different machining methods (milling, grinding, and scraping), and their rough surface profiles are extracted. The structure function method was used to calculate each profile's fractal dimension and scale coefficient. Both theoretical analysis and experimental results of contact stiffness are obtained for these specimens under different contact loads. The comparison between the theoretical contact stiffness and the experimental results at the interface indicates that the present fractal model for the contact stiffness is appropriate and the theoretical contact stiffness is consistent with the experimental data. © 2010 by ASME. Source


Yang X.-J.,China University of Mining and Technology | Machado J.A.T.,Polytechnic Institute of Porto | Hristov J.,University of Chemical Technology and Metallurgy of Sofia
Nonlinear Dynamics | Year: 2015

The local fractional Burgers’ equation (LFBE) is investigated from the point of view of local fractional conservation laws envisaging a nonlinear local fractional transport equation with a linear non-differentiable diffusion term. The local fractional derivative transformations and the LFBE conversion to a linear local fractional diffusion equation are analyzed. © 2015 Springer Science+Business Media Dordrecht Source


Xie F.,Jiangsu University | Hou Y.,China University of Mining and Technology
Industrial Lubrication and Tribology | Year: 2011

Purpose - The purpose of this paper is to reveal the characteristics of hydrodynamic load capacity and torque transferred by oil film with variable viscosity, and the effect of groove number, width and depth on the hydrodynamic load capacity and torque transfer. Design/methodology/approach - The radial temperature of friction pair and viscosity of YLA-N32 hydraulic oil were measured through experiments, and a viscosity-diameter expression was deduced using polynomial fitting method. Analytical expressions for hydrodynamic load capacity and torque of the oil film were deduced based on hydrodynamic lubrication theory. Findings - The investigation shows the hydrodynamic load capacity and transferred torque with variable viscosity are much less than that with constant viscosity. Load capacity increases with the increase of groove depth which is the most significant influence factor, while it has the least influence on torque. Groove width has great influence on load capacity and torque. The load capacity increases with the increase of groove width; contrarily, torque decreases with the increase of groove width. Groove number has little influence on load capacity, while it has great influence on torque. The torque decreases with the increase of groove number. Originality/value - In this paper, analytical solutions for hydrodynamic load capacity and torque of the oil film with variable viscosity are deduced. The paper reveals the relationship between hydrodynamic load capacity, torque transfer and groove number, width and depth. © Emerald Group Publishing Limited. Source


Li H.-J.,China University of Mining and Technology | Xiao B.,China Institute of Technology
Kongzhi Lilun Yu Yingyong/Control Theory and Applications | Year: 2012

This paper brings forward a multistep predictive model based on the recurrent backpropagation (BP) neural network for the control systems with strong nonlinearity and multiple set-points. By analyzing the internal mathematical relation of the predictive model, we select a quadratic function as the objective function for the multistep predictive controller. For this objective function, we compute the Jacobian matrix and Hessian matrix of the control sequence, and design the receding horizon optimization strategy using Newton-Rhapson algorithm, thus, constituting a nonlinear multistep model predictive controller. Simulation results show desirable performances of the model predictive controller. Source


Liu C.-M.,Xuzhou Normal University | Ma J.-Q.,China University of Mining and Technology | Sun Y.-Z.,Xuzhou Normal University
Experimental and Toxicologic Pathology | Year: 2012

Puerarin (PU), a natural flavonoid, has been reported to have many benefits and medicinal properties. In this study, we valuated the protective effect of puerarin against lead-induced oxidative DNA damage and apoptosis in rat liver. A total of forty male Wistar rats (8-week-old) was divided into 4 groups: control group; lead-treated group (500. mg Pb/l as the only drinking fluid); lead. +. puerarin treated group (500. mg Pb/l as the only drinking fluid plus 400. mg PU/kg. bwt intra-gastrically once daily); and puerarin-treated group (400. mg PU/kg. bwt intra-gastrically once daily). The experimental period was lasted for 75 successive days. Our data showed that puerarin significantly effectively improved the lead-induced histology changes in rat liver and decreased the serum ALT and AST activities in lead-treated rats. Puerarin markedly restored Cu/Zn-SOD, CAT and GPx activities and the GSH/GSSG ratio in the liver of lead-treated rat. Furthermore, the increase of 8-hydroxydeoxyguanosine induced by lead was effectively suppressed by puerarin. The enhanced caspase-3 activity in the rat liver induced by lead was also inhibited by puerarin. TUNEL assay showed that lead-induced apoptosis in rat liver was significantly inhibited by puerarin, which might be attributed to its antioxidant property. In conclusion, these results suggested that puerarin could protect the rat liver against lead-induced injury by reducing ROS production, renewing the activities of antioxidant enzymes and decreasing DNA oxidative damage. © 2010. Source


Liu C.-M.,Jiangsu University | Sun Y.-Z.,Jiangsu University | Sun J.-M.,Jiangsu University | Ma J.-Q.,China University of Mining and Technology | Cheng C.,Jiangsu University
Biochimica et Biophysica Acta - General Subjects | Year: 2012

Background: Lead (Pb) exposure is considered as a risk factor for the development of renal dysfunction. The flavonoid quercetin (QE) in diets exerts the nephroprotective effects. This study investigated the effects of quercetin on renal oxidative stress and inflammation in rats exposed to Pb. Methods: Wistar rats were divided into normal, lead exposure groups, lead plus quercetin groups and quercetin groups. Rats were exposed to lead acetate in the drinking water (500 mg Pb/L) with or without quercetin co-administration (25 and 50 mg QU/kg intragastrically once daily). After 75 days, serum uric acid, urea, creatinine, renal reactive oxygen species (ROS) production, thiobarbituric acid reactive substances (TBARS) and histopathological analysis were performed. Pb content in kidney was also assayed. The levels of tumor necrosis factor-alpha (TNF-α), interleukin-1beta (IL-1β), interleukin-6 (IL-6), cyclooxygenase-2 (COX-2), the extracellular-receptor kinases (ERK1/2), the c-Jun N-terminal kinases (JNK1/2), p38 MAPK and nuclear factor-κB (NF-κB) were measured. Results: Quercetin significantly prevented Pb-induced nephrotoxicity in a dose-dependent manner, indicated by both diagnostic indicators and histopathological analysis. Quercetin significantly decreased Pb content in kidney. Pb-induced profound elevations of oxidative stress in kidney were suppressed by quercetin. Furthermore, quercetin significantly inhibited Pb-induced inflammation in rat kidney. Conclusions: These results suggest that quercetin has the nephroprotective actions. The inhibition of Pb-induced kidney inflammation by quercetin is due at least in part to its anti-oxidant activity and its ability to modulate the MAPK and NF-κB signaling pathway. General significance: Quercetin might be a potent nephroprotective drug to protect Pb-induced kidney injury. © 2012 Elsevier B.V. Source


Xu B.,Beijing Research Institute of Chemical Defense | Hou S.,China University of Mining and Technology | Cao G.,Beijing Research Institute of Chemical Defense | Wu F.,Beijing Institute of Technology | Yang Y.,Beijing Research Institute of Chemical Defense
Journal of Materials Chemistry | Year: 2012

Gelatin, a renewable animal derivative composed of various proteins, was used as a precursor for nitrogen-doped porous carbon with high surface areas for supercapacitors for the first time. The preparation procedure is very simple, including the carbonization of gelatin under inert atmosphere, followed by NaOH activation of the carbonized char at 600 °C for 1 h. The porosity and surface chemistry of the carbon depend strongly on the weight ratio of NaOH/char, with the specific surface area and nitrogen content varying between 323 and 3012 m 2 g -1 and between 0.88 and 9.26 at%, respectively. The unique microstructure and nitrogen functionalities enable the carbon to exhibit a high capacitance of up to 385 F g -1 in 6 mol L -1 KOH aqueous electrolytes, attributed to the co-contribution of double layer capacitance and pseudo-capacitance. It also shows excellent rate capability (235 F g -1 remained at 50 A g -1) and cycle durability, making it a promising electrode material for supercapacitors. This journal is © The Royal Society of Chemistry. Source


Liu Z.,China University of Mining and Technology | Liu Z.,Nanjing Southeast University | Zhang Y.,Nanjing Southeast University | Jiang Q.,Nanjing Southeast University
Construction and Building Materials | Year: 2014

The electrical resistivity changes with time of cement pastes with water to cement ratio of 0.23, 0.35 and 0.53 were in situ continuously monitored by using a non-contact resistivity apparatus. To aid in understanding the evolution of effective resistivity, a hydration model CEMHYD3D was then utilized to simulate the early age formation of microstructure. Based on the effective media theory, the relationship between the change of relative resistivity and the evolution of total porosity, tortuosity factor and constrictivity is established. The results show that a lower water to cement ratio shows a smaller porosity and constrictivity as well as a higher tortuosity factor. Moreover, according to the experimental and simulated results, it is found that the evolution of resistivity is not only controlled by capillary pores but also C-S-H phases. Before arriving fully de-percolation time of capillary pores, the reduction of pores connectivity shows a higher influence on the paste resistivity than the decrease of capillary porosity. After that, the resistivity change of cement paste is mainly determined by the volume fraction of C-S-H. © 2013 Elsevier Ltd. All rights reserved. Source


Yang Y.,China University of Mining and Technology
Energy Education Science and Technology Part A: Energy Science and Research | Year: 2014

Coal enterprise marketing is the top priority in business operations. Results of coal enterprise marketing will have a direct bearing on the fate of enterprise development and the performance of coal enterprise marketing has become a hot topic in current society, especially in sales division in the business. Thus, effective revaluation of enterprise performance is also very popular in business and management research due to its realistic and important business meaning. Among those, one of the most important topics is to construct evaluation method by using various index systems, which it is not only easy to operate, but also to measure results of enterprise marketing effectively. This paper applies various evaluation indicators to establish the coal production and sale close index, in order to reflect the coal marketing management status, and the index was also quantified by use of principal component analysis. In which the correlation coefficient of production, type, quality, sales organization, storage and shipping system, and sales of the coal will be analyzed in detail in this model. Quantitative method is used in this model and data is from evaluation of the degree of convergence and major coal enterprises with internal departments in key aspects of the marketing process. This methodology not only measures the marketing result effectively, but also minimizes non-essential elements. In addition, it also can enhance marketing management level, establish an effective marketing system and improve economic performance. © Sila Science. All rights reserved. Source


Niu S.,Henan Polytechnic University | Jing H.,China University of Mining and Technology | Liang J.,Shanghai Institute of Geotechnical Engineering Co.
Yanshilixue Yu Gongcheng Xuebao/Chinese Journal of Rock Mechanics and Engineering | Year: 2011

As the existing studies in failure modes of rock under different loading paths are less, uniaxial compression, conventional triaxial compression, pre-peak and post-peak unloading confining pressure tests of sandstone are respectively conducted with the MTS815 rigid servo-controlling testing machine. Based on test results, the failure modes of sandstone under different loading paths are studied. According to the energy analysis of sandstone specimens before and after failure, the reasons for existences of different failure modes under different loading paths are discussed by means of energy dissipation theory. The results show that the main failure mode of sandstone specimens in uniaxial compression tests is splitting failure, while single shear failure is complement. The main failure mode is single shear or splitting failure under low confining pressure in conventional triaxial compression and post-peak unloading confining pressure tests; when the confining pressure is higher, combination failure modes of single shear and splitting failure mainly occurs. Under the per-peak unloading confining pressure tests, combination failure modes of shear and transverse shear of sandstone specimens mainly occurs under low confining pressure. On the contrary, combination failure modes of splitting and shear mainly occurs under high confining pressure. With the increasing confining pressure, shear failure occurs easily under triaxial compression; but the probability of shear failure occurrence increases at first, then decreases under pre-peak and post-peak unloading confining pressure. The failure modes under different loading paths are related with the energy values of sandstone specimens before and after failure. When the energy value is low, single failure mode occurs easily with intact broken block. When the energy value is high, combination failure modes occur easily with crushed block. Source


Lin H.,Central South University | Sun S.,China University of Mining and Technology
Disaster Advances | Year: 2012

Layered rock mass slopes widely existed in the practice of geotechnical engineering. Therefore, the study of their deformation and mechanical properties is essential for the safe design of slopes. This study uses FLAC3D numerical calculation software to simulate interactions between layered rock mass slope and pile. In the process of numerical simulation, a three-spring pile unit is employed to simulate piles placed in six positions of the slope. By changing the length of the pile, this article performs a research on the reinforcement effect of pile from different influencing factors, such as overall displacement of slope, monitoring point displacement and shear stress of slope rock mass. The analysis reveals that, when pile positions are set at the middle and lower parts to ensure that piles pass through the most dangerous slip surface, the best deformation effect of rock mass results. Piles at the slope toe helps change the stress condition of the corresponding rock mass and decrease the stress concentration phenomenon. As the pile length increases, the displacement saltation in the slope occurs on a gradually decreasing basis and presents a well-distributed changing trend. A critical pile length exists and controlling displacement by proceeding with increasing pile length renders no obvious effect when the length goes beyond critical pile length. Source


Liu Z.-W.,Luoyang Institute of Science and Technology | Li Y.-H.,China University of Mining and Technology
Gongcheng Lixue/Engineering Mechanics | Year: 2010

The digital speckle correlation method (DSCM) and the software package PhotoInfor have been adopted to conduct an experimental investigation on the deformation and crack behaviours through a uniaxial compressive test on a rock specimen of 100 mm×100 mm×100 mm with a hole. DSCM was used to measure the deformation fields of displacement and strain, and to observe the general average deformation on the whole specimen surface during the test. The results show that: 1) the deformation process of rock specimen during the test can be captured and better understood by DSCM; 2) the local deformation occurs when the axial compressive displacement reachs to 80% of the total displacement at peak load point, and the characteristics of deformation localization is the strongest near the peak load, and 3) the curves of average maximum shear strains and axial compressive displacement on the specimen have an obvious relationship with the evolution of deformation and crack on rock specimen, and these can provide some significant reference for studying the local deformation characters of rock undergoing compressive loads. Source


Yang X.-J.,China University of Mining and Technology | Yang X.-J.,Qujing Normal University | Srivastava H.M.,University of Victoria | He J.-H.,Soochow University of China | And 3 more authors.
Physics Letters, Section A: General, Atomic and Solid State Physics | Year: 2013

In this Letter, we propose to use the Cantor-type cylindrical-coordinate method in order to investigate a family of local fractional differential operators on Cantor sets. Some testing examples are given to illustrate the capability of the proposed method for the heat-conduction equation on a Cantor set and the damped wave equation in fractal strings. It is seen to be a powerful tool to convert differential equations on Cantor sets from Cantorian-coordinate systems to Cantor-type cylindrical-coordinate systems. © 2013 Elsevier B.V. All rights reserved. Source


Qiu L.,China University of Mining and Technology
Communications in Theoretical Physics | Year: 2013

Taking into account the intrinsic decoherence, we have investigated quantum correlations in a two-qubit Heisenberg XX model when a nonuniform magnetic field is included. We compare entanglement measured by entanglement of formation, quantum discord and measurement-induced measurement (MID) and illustrate their different characteristics. Quantum discord and MID show the same features and always exist even though there is no entanglement in the long time limit. In the time evolution, quantum discord could be generated or enhanced to the stable value, while MID just decreases to the stable value. © 2013 Chinese Physical Society and IOP Publishing Ltd. Source


Cheng L.,CAS Institute of Atmospheric Physics | Zhu J.,CAS Institute of Atmospheric Physics | Reseghetti F.,New Energy Technologies | Liu Q.,China University of Mining and Technology
Journal of Atmospheric and Oceanic Technology | Year: 2011

A new technique to estimate three major biases of XBT probes (improper fall rate, start-up transient, and pure temperature error) has been developed. Different from the well-known and standard "temperature error free" differential method, the new method analyses temperature profiles instead of vertical gradient temperature profiles. Consequently, it seems to be more noise resistant because it uses the integral property over the entire vertical profile instead of gradients. Its validity and robustness have been checked in two ways. In the first case, the new integral technique and the standard differential method have been applied to a set of simulated XBT profiles having a known fall-rate equation to which various combinations of pure temperature errors, random errors, and spikes have been added for the sake of this simulation. Results indicated that the single pure temperature error has little impact on the fall-rate coefficients for both methods, whereas with the added random error and spikes the simulation leads to better results with the new integral technique than with the standard differential method. In the second case, two sets of profiles from actual XBT versus CTD comparisons, collected near Barbados in 1990 and in the western Mediterranean (2003-04 and 2008-09), have been used. The individual fall-rate coefficients and start-up transient for each XBT profile, along with the overall pure temperature correction, have been calculated for the XBT profiles. To standardize procedures and to improve the terms of comparison, the individual start-up transient estimated by the integral method was also assigned and included in calculations with the differential method. The new integral method significantly reduces both the temperature difference between XBT and CTD profiles and the standard deviation. Finally, the validity of the mean fall-rate coefficients and the mean start-up transient, respectively, for DB and T7 probes as precalculated equations was verified. In this case, the temperature difference is reduced to less than 0.1°C for both datasets, and it randomly distributes around the null value. In addition, the standard deviation on depth values is largely reduced, and the maximum depth error computed with the datasets near Barbados is within 1.1% of its real value. Results also indicate that the integral method has a good performance mainly when applied to profiles in regions with either a very large temperature gradient, at the thermocline or a very small one, toward the bottom. © 2011 American Meteorological Society. Source


Liu W.L.,China University of Mining and Technology
Energy Education Science and Technology Part A: Energy Science and Research | Year: 2014

The measurement of deformations around a coal-mining face is an extremely difficult task due to the time and space constraints in such sites. In order to reduce the inherent risks of danger during working around such difficult areas, it requires quick, precise and automatic measuring the dynamic changes of coal-mining face in real-time. Therefore, an in-situ approach of using 3D laser scanning technique to measure the deformations of coal-mining face is proposed, which can provide direct co-ordinate measurement and an instant three dimensional model with very data density and high accuracy; also it allows the users to analyze the data in real-time. Through statistical evaluation of the three dimensional model surface derived from the cloud of points, it can differentiate the different discontinuity sets on the coal-mining face. Therefore, the mechanics engineer with comprehensive information to calculate the 3D spatial variation in coal-mining face is obtained. The trial results show that using this technology to measure the deformation in coal-mining face can realize automation, high-speed and real-time. © Sila Science. All rights reserved. Source


Talhelm T.,University of Virginia | Haidt J.,New York University | Oishi S.,University of Virginia | Zhang X.,Beijing Normal University | And 2 more authors.
Personality and Social Psychology Bulletin | Year: 2015

Henrich, Heine, and Norenzayan summarized cultural differences in psychology and argued that people from one particular culture are outliers: people from societies that are Western, educated, industrialized, rich, and democratic (WEIRD). This study shows that liberals think WEIRDer than conservatives. In five studies with more than 5,000 participants, we found that liberals think more analytically (an element of WEIRD thought) than moderates and conservatives. Study 3 replicates this finding in the very different political culture of China, although it held only for people in more modernized urban centers. These results suggest that liberals and conservatives in the same country think as if they were from different cultures. Studies 4 to 5 show that briefly training people to think analytically causes them to form more liberal opinions, whereas training them to think holistically causes shifts to more conservative opinions. © 2014 by the Society for Personality and Social Psychology, Inc. Source


Yao J.,China University of Mining and Technology
World Transactions on Engineering and Technology Education | Year: 2015

Learning interaction is a two-way exchange of communication by which the learners obtain, interpret and challenge points covered in the learning. As a major means of knowledge transfer, good learning interaction can facilitate the learners' learning outcomes. In the on-line learning process, the interaction between learners and learning resources is the most important interactive mode. However, the lack of interactive elements in the design of existing on-line learning resources leads to a higher cognitive load for learners during the process and the learning outcomes are hard to guarantee. The work outlined in this article was based on cognitive load theory. Analysis of the deficiency of instructional design in on-line learning resources is presented. Also put forward is an open and interactive e-learning multilayer model and a human machine interface design that can be achieved by applying focus and context methods from visualisation technology. This enhances the interactivity of on-line learning resources and reduces the cognitive load of the target learners. © 2015 WIETE. Source


Li H.,Dalian University of Technology | Mu H.,Dalian University of Technology | Zhang M.,China University of Mining and Technology | Li N.,Dalian University of Technology
Energy Policy | Year: 2011

With the intensification of global warming and continued growth in energy consumption, China is facing increasing pressure to cut its CO2 (carbon dioxide) emissions down. This paper discusses the driving forces influencing China's CO2 emissions based on Path-STIRPAT model-a method combining Path analysis with STIRPAT (stochastic impacts by regression on population, affluence and technology) model. The analysis shows that GDP per capita (A), industrial structure (IS), population (P), urbanization level (R) and technology level (T) are the main factors influencing China's CO2 emissions, which exert an influence interactively and collaboratively. The sequence of the size of factors' direct influence on China's CO2 emission is A>T>P>R>IS, while that of factors' total influence is A>R>P>T>IS. One percent increase in A, IS, P, R and T leads to 0.44, 1.58, 1.31, 1.12 and -1.09 percentage change in CO2 emission totally, where their direct contribution is 0.45, 0.07, 0.63, 0.08, 0.92, respectively. Improving T is the most important way for CO2 reduction in China. © 2011 Elsevier Ltd. Source


Hu Z.,Tsinghua University | Si X.,China University of Mining and Technology | Zhang Z.,Tsinghua University | Wen X.,Tsinghua University
Desalination | Year: 2014

In the paper, fouling behavior of a synthetic secondary effluent was explored and influences of membrane fouling and operation pressures (25, 30, 50, and 75. kPa) on rejection of five endocrine disrupting chemicals (EDCs) (estrone, 17β-estradiol, estriol, 17α-ethynyl estradiol, and bisphenol A) were explored during the membrane filtration process using 100. kDa polyvinylidene fluoride (PVDF) ultrafiltration (UF) membrane under constant pressure dead-end filtration system. Fouling behavior of humic compounds was found to obey the rule of cake filtration. Fouled UF membrane revealed enhanced EDCs removal rate by 0.0% to 58.3% corresponding to different EDCs. Cakes grew under various pressures had different specific resistances and porosities. Cake formed under 50. kPa had the lowest porosity 56.8% but had the best EDCs removal efficiency, which may be attributed to adsorption and size exclusion. Besides, EDCs revealed different penetration abilities through fouled membrane with E3 being the most easy to flow out. It can be concluded that 50. kPa may be suitable for UF process operation aiming at EDCs removal and appropriate flux. © 2014 Elsevier B.V. Source


Wang Z.,China University of Mining and Technology
Lecture Notes in Electrical Engineering | Year: 2015

The development framework is the basic and core software resource which can provide a general and reusable structure among all the software applications. This paper proposes a rapid development framework (RDF) of enterprise information system based on software components and JavaEE, the paper not only describes the framework’s structure and the detailed functions of each parts in RDF, but also gives an application example. The development practice proves that this framework has good maintainability, extendibility and stability, it can meet the development needs of most software applications. © Springer-Verlag Berlin Heidelberg 2015. Source


Wang Y.-F.,China University of Mining and Technology | Wang Y.-F.,China Coal Technology and Engineering Co. | Li Y.-Z.,China Coal Technology and Engineering Co.
Meitan Xuebao/Journal of the China Coal Society | Year: 2012

In view of the problem of gas drainage from holes through coal in the low permeability coal seam, a new permeability improvement technology of directional hydraulic penetration by guided groove was put forward. The directional hydraulic fracturing of guided groove hole directed by guided groove and control hole, the coal between guided groove hole and control hole was penetrated, and took coal out by high pressure water, made the hole controlled coal loose stress, and improved the coal permeability effectively. The directional hydraulic mechanism was put forward and analyzed. Permeability improvement technology of directional hydraulic penetration by guided groove was described and studied in detail. The in-situ experimental results show that gas drainage scope rise more than 1 time, the hole flow increases by an average of 3.87 times, boreholes engineering reduce 65%. Source


Guo Z.-P.,Shandong University of Science and Technology | Huang W.-P.,China University of Mining and Technology
Meitan Xuebao/Journal of the China Coal Society | Year: 2011

Using mine pressure theory, rock plate theory and method of numerical simulation, the filling parameter of gangue strip-filling working face in a coal mine was optimized, and the scheme filling 60 m and leaving 25 m was confirmed. According to numerical simulation, it was obtained that the fillings plastic zone proportional coefficient and the fillings width show power exponential function of concave shape. Then the fillings were regarded as elastic-plastic body to establish the mechanics model which included rectangle thin rock plate and fillings. Using plate mechanics and material mechanics theory, the calculation formula of the largest displacement of the roof was obtained, and the largest displacement of main roof plate was accounted to 8.73 cm, which shows that the result anastomoses with numerical simulation. Source


Chen L.,China University of Mining and Technology | Wu Z.,Shandong University
ESAIM - Control, Optimisation and Calculus of Variations | Year: 2012

In this paper, we study one kind of stochastic recursive optimal control problem for the systems described by stochastic differential equations with delay (SDDE). In our framework, not only the dynamics of the systems but also the recursive utility depend on the past path segment of the state process in a general form. We give the dynamic programming principle for this kind of optimal control problems and show that the value function is the viscosity solution of the corresponding infinite dimensional Hamilton-Jacobi-Bellman partial differential equation. © EDP Sciences, SMAI, 2012. Source


Meng Q.-R.,China University of Mining and Technology
International Journal of Structural Integrity | Year: 2014

Purpose - The purpose of this paper is to reveal the temperature rise characteristics of the disc and pads under different load types. Design/methodology/approach - Evolutions of the disc and pads temperature under a stable, gradual changing and sine-wave contact pressures widely used at present are analyzed numerically by using ANSYS software. Findings - The results show that during the loading process, the temperature increases most rapidly under a stable contact pressure, most slowly under a gradual changing contact pressure; the disc temperature rise curves expose saw-shaped character, the closer it is to the friction surface, the more serious the fluctuations will be, the pads temperature rise curves are rather smooth; temperature gradient in the axial direction is higher than that in the other two directions under all of the three types of contact pressure and shows a sine-wave variation under a sine-wave contact pressure. Originality/value - It indicates that a gradual changing contact pressure should be adopted preferentially in practical application. The simulation results of this work provide theoretical basis for load simulation. Copyright © 2014 Emerald Group Publishing Limited. All rights reserved. Source


Zhang Y.-F.,China University of Mining and Technology | Mei J.-Q.,Dalian University of Technology
Communications in Theoretical Physics | Year: 2012

A 3 × 3 matrix Lie algebra is first introduced, its subalgebras and the generated Lie algebras are obtained, respectively. Applications of a few Lie subalgebras give rise to two integrable nonlinear hierarchies of evolution equations from their reductions we obtain the nonlinear Schrödinger equations, the mKdV equations, the Broer-Kaup (BK) equation and its generalized equation, etc. The linear and nonlinear integrable couplings of one integrable hierarchy presented in the paper are worked out by casting a 3 × 3 Lie subalgebra into a 2 × 2 matrix Lie algebra. Finally, we discuss the elliptic variable solutions of a generalized BK equation. © 2012 Chinese Physical Society and IOP Publishing Ltd. Source


Zhao Y.,Jilin University | Baleanu D.,King Abdulaziz University | Baleanu D.,Cankaya University | Baleanu D.,Romanian Space Science Institute | And 3 more authors.
Advances in High Energy Physics | Year: 2013

Maxwell's equations on Cantor sets are derived from the local fractional vector calculus. It is shown that Maxwell's equations on Cantor sets in a fractal bounded domain give efficiency and accuracy for describing the fractal electric and magnetic fields. Local fractional differential forms of Maxwell's equations on Cantor sets in the Cantorian and Cantor-type cylindrical coordinates are obtained. Maxwell's equations on Cantor set with local fractional operators are the first step towards a unified theory of Maxwell's equations for the dynamics of cold dark matter. © 2013 Yang Zhao et al. Source


Pan C.,China University of Mining and Technology | Stanbury D.M.,Auburn University
Journal of Physical Chemistry A | Year: 2014

The reaction of ClO2 · with S2O 3 2- in aqueous solution is a component of the "crazy clock" reaction of ClO2 - with S2O 3 2-, and under conditions of excess S2O 3 2- the absorbance at 360 nm due to ClO2 · decays with sigmoidal kinetics. A chain reaction mechanism is inferred on the basis that very small concentrations of SO3 2- accelerate the reaction, and methionine inhibits the reaction. Pseudo-first-order kinetics is observed in the presence of relatively large methionine concentrations, leading to the simple rate law -d[ClO2]/dt = (ka[S2O3 2-] + k b[S2O3 2-]2)[ClO 2], with ka = 45216 M-1 s-1 and kb = (5.7 0.2) × 105 M-2 s-1 at 25 °C and pH 7.6. Under these conditions, the initial products are ClO2 - and S4O6 2-. A classical electron-transfer mechanism is assigned to the reaction that occurs under conditions of methionine inhibition. © 2014 American Chemical Society. Source


Li Y.,China University of Mining and Technology
Meitan Xuebao/Journal of the China Coal Society | Year: 2011

This paper analysed the overburden movement in cemented backfill mining by using computer simulated model, observed the overburden movement in different mining advances distance, compared to traditional longwall mining and fonnd the characteristic of overburden movement in backfill mining. The overburden movement in solid waste rock cemented backfill mining was different from what it was in traditional longwall mining. The studies show that the range of periodic weighting is relatively wide in back fill mining, and the weighting strength is also low; the key rock strata will be bending subsidence without failure situation. The displacement of overburden movement can be dramatically decreased. As a result, ground surface deformation can be well controlled. Source


Liu J.-C.,China University of Mining and Technology | Wang J.-G.,Northwestern Polytechnical University
CMES - Computer Modeling in Engineering and Sciences | Year: 2014

We consider the determination of heat flux within a body from the Cauchy data. The aim of this paper is to seek an approach to solve the onedimensional heat equation in a bounded domain without initial value. This problem is severely ill-posed and there are few theoretic results. A quasi-reversibility regularization method is used to obtain a regularized solution and convergence estimates are given. For numerical implementation, we apply a method of lines to solve the regularized problem. From numerical results, we can see that the proposed method is reasonable and feasible. Copyright © 2014 Tech Science Press. Source


Zhou F.-B.,China University of Mining and Technology
Meitan Xuebao/Journal of the China Coal Society | Year: 2012

The investigation of gas and coal spontaneous combustion in 229 coal mines of main mining areas in China shows that 74 mines suffer from the coexistence of gas and spontaneous combustion of coal, the number of which has a increasing trend with the mining depth growing. So the coal disaster mechanism caused by the coexistence of gas and spontaneous combustion was studied, which proved that disasters arise only from the intersection area of CH 4, O 2 and heat in cracks. What's more, the mathematical model of multi-gas migrating in cracks was built upon definite data, establishing the relationship between mass concentration and velocity of gases such as N 2, O 2 and CH 4. At last, typical disaster cases in coal mines was analyzed to verify the practicability of disaster mechanism of gas and coal spontaneous combustion coexistence. Source


Jiang M.,CAS Institute of Physics | Lv Q.Z.,China University of Mining and Technology | Sheng Z.M.,Shanghai JiaoTong University | Grobe R.,Illinois State University | Su Q.,Illinois State University
Physical Review A - Atomic, Molecular, and Optical Physics | Year: 2013

We study the creation of electron-positron pairs induced by two spatially separated electric fields that vary periodically in time. The results are based on large-scale computer simulations of the time-dependent Dirac equation in reduced spatial dimensions. When the separation of the fields is very large, the pair creation is caused by multiphoton transitions and mainly determined by the frequency of the fields. However, for small spatial separations a coherence effect can be observed that can enhance or reduce the particle yield compared to the case of two infinitely separated fields. If the travel time for a created electron or positron between both field locations becomes comparable to the period of the oscillating fields, we observe peaks in the energy spectrum which can be explained in terms of field-induced transient bound states. © 2013 American Physical Society. Source


Long J.,China University of Mining and Technology
Caikuang yu Anquan Gongcheng Xuebao/Journal of Mining and Safety Engineering | Year: 2016

In response to the difficulties during the surrounding rock control in deep roadway, based on previous research and engineering practices, the mechanism of synergetic anchorage in deep roadway surrounding rock has been put forward, taking synergetics as its theoretical basis and guideline. Through analyzing the components of the controlling system of the roadway surrounding rock, and introducing the way how synergetics direct the anchorage of surrounding rocks, a research framework has been built to propose the synergetic mechanisms concerning structure, intensity, rigidity, anchorage timing, preload, and deformation. The study shows that the synergetic anchorage system achieves the effect of 1+1>2, as its macroscale function outweighs the sum of its total subsystems. This is of fundamental and vital importance to the stability control of the deep roadway surrounding rock, and meets the essential needs of safety production of coal. © 2016, China University of Mining and Technology. All right reserved. Source


Wang X.-W.,China University of Mining and Technology
Meitan Xuebao/Journal of the China Coal Society | Year: 2013

Rectangular coordinate system was established, and its origin of coordinates was the centroid of the screen, y-axis points to the center of vibration exciter. Through the force analysis and solving differential equation of single-shaft vibrating screen, it could get the analytical expressions of the displacement of the screen at any point, it is found that motion of centroid of the screen is the circular and the motion of point (0, -R') is straight reciprocating motion, the amplitude is equal to the radius of the circle, the motion of single-shaft vibrating screen could be simulated by the connecting rod of crank-connecting rod-slide block mechanism. Using the geometrical method, it could identify displacement of any point on the screen, thus it depicts the trajectory of the point. Using the method of instantaneous center of velocity of connecting rod, it could get the velocity of any point of the screen at any time. Using the particle motion parabola and method of time half step, it could find the instantaneous position of the particle and the screen surface at any time, the complex movement of the particle and the screen surface gets simple and intuitive. Source


Liu F.,CAS Technical Institute of Physics and Chemistry | Liu F.,China University of Mining and Technology | Tian H.,CAS Technical Institute of Physics and Chemistry | He J.,CAS Technical Institute of Physics and Chemistry
Journal of Colloid and Interface Science | Year: 2014

Due to specific properties, core-shell Fe3O4@SiO2 and core-shell-shell Fe3O4@nSiO2@mSiO2 nanostructures have been extensively investigated for the contamination treatment of wastewater. However, these reported materials were usually used as advanced adsorbents or catalyst-supports. In this study, we demonstrate that magnetic mesoporous silica Fe3O4@nSiO2@mSiO2 microspheres can not only exhibit excellent adsorptive performance for removal of DDT (1,1,1-trichloro-2,2-bis(4-chlorophenyl) ethane) from aqueous media, but also display high catalytic activity. Over 97% of DDT could be quickly removed from aqueous media in 60min. At 60°C the DDE (1,1-dichloro-2,2-bis(4-chlorophenyl) ethylene) content increases greatly as DDT disappears completely, and is decomposed completely after thermal treatment at a relatively low temperature of 450°C. The obtained magnetic mesoporous silica nanoparticles were characterized by X-ray diffraction, transmission electron microscopy, nitrogen adsorption-desorption measurements and vibrating sample magnetometer. The results indicate that Fe3O4@nSiO2@mSiO2 microspheres show strong superparamagnetism and have high specific surface area (577m2g-1). © 2013 Elsevier Inc. Source


Li L.,China University of Mining and Technology
Research Journal of Applied Sciences, Engineering and Technology | Year: 2013

Due to economic and functional factors, forms and functions of college's multifunctional stadiums become more and more diversified. The utility rate increases. Density increases. Therefore dense crowd's evacuation should be noticed. Although many scholars have some deep researches on fire alarming and evacuation, they usually conduct only an aspect in ideal situations. The performances consider both primary disaster and secondary disaster are rare. This study, taking delaying and broaching situation in fire dense crowd's evacuation route design as background, guided by integrating analysis of fire alarming system and dense crowd's evacuation, considering relative factors, according to performance-based evacuation design, theory of accident consequence chain, clustering flow theory, etc, by calculating the delaying number quantitative modeling in travel time method, clarifies the design thoughts and clears the design principles. Meanwhile, this study proves the effects of fire primary disaster and secondary disaster and mark relative parameters. It can not only provide references for practical building designs, but also be a tool for managing and preventing the aggregations of various dangerous factors. © Maxwell Scientific Organization, 2013. Source


Heng L.,CAS Beijing National Laboratory for Molecular | Wang X.,China University of Mining and Technology | Yang N.,CAS Beijing National Laboratory for Molecular | Zhai J.,CAS Beijing National Laboratory for Molecular | And 3 more authors.
Advanced Functional Materials | Year: 2010

In this paper, a new type of flexible working electrode, TiO 2/Cul/Cu, is reported, in which the p-n junction of TiO 2-Cul is introduced into dyesensitized solar cells (DSSCs) for the first time. The devices give a high conversion efficiency of up to 4.73% under 1 sun illumination. The excellent performance is ascribed to the existence of the p-n junction, which forms a single directional pathway for electron transport which benefits the charge separation, and improves the efficiency of the flexible solar cells as a result. © 2010 WILEY-VCH Verlag GmbH & Co. KGaA. Source


Pan T.,China University of Mining and Technology
Proceedings - 2010 International Conference on Intelligent System Design and Engineering Application, ISDEA 2010 | Year: 2011

Wireless communication is very important for the safety production in coal mine. In this paper, two key technologies which are operating frequency and network structure about the wireless communication system in the coal mine tunnel have been studied. Through the study, we get the conclusion that the recommended operating frequency is above 2GHz and the favorable network structure adopts the structure of base station with switch. We also develop a multifunction wireless communication system which can achieve the functions of wireless communication, personnel management and video surveillance. Practical applications showed that the multifunction wireless communication system can satisfy the need about wireless dispatch communication in the coal mine tunnel. © 2010 IEEE. Source


Dong S.L.,China University of Mining and Technology
Applied Mechanics and Materials | Year: 2014

With the development of the enterprises, as important factors, human resources plays an vital role in company. Comparative human resources are hungrily needed in the combination of various resources in enterprise management. However, at present, most of enterprises are unable to make full use of the human resources and cannot stimulate the huge potential, which can't configurate human resources effectively and cause great waste of human cost. From the angle of saving labor costs and improving the efficiency, according to the basic principle and method of human resource configuration, this paper, based on a specific project as the background, suitable for human resource configuration of particular project, use the model of assignment problem in operational research, accomplish the optimal combination of number and projects and solve the problem of the waste of human resource. © (2014) Trans Tech Publications, Switzerland. Source


Zhang X.-J.,Shandong University of Technology | Zhang X.-J.,China University of Mining and Technology
Caikuang yu Anquan Gongcheng Xuebao/Journal of Mining and Safety Engineering | Year: 2011

Rock burst occurs in shallow part of surrounding rock such as loose, flake off, sound, rock-chip ejection, so it mainly belongs to splitting failure. For the splitting rock burst problem of integrated hard and brittle surrounding rocks, loading and unloading tests of true triaxial compression to simulate the actual stress evolution of surrounding rock and unload one-sided principal stress are conducted using the mineral of gabbro. In order to facilitate comparative analysis, the biaxial compression tests were carried out at the same time. Finally, the mechanism of splitting rock burst is analyzed based on the test results. Although the phenomena of splitting rock burst are gained by two kinds of test methods, the maximum principal stress needed for unloading splitting rock burst is much smaller than that of biaxial compression test; the scope of the two kinds of splitting rock burst is different and unloading splitting rock burst occurs near the unloading surface which is in accord with the actual situation of rock burst; intermediate principal stress plays an important role in splitting rock burst. The research findings provide a basis for analyzing the condition and mechanism of splitting rock burst. Source


Han D.Y.,China University of Mining and Technology
Applied Mechanics and Materials | Year: 2014

The techniques are referred to as analyzing the relationship between the events of the lithosphere getting thermal and the changes of weakened release energies of strong earthquakes that might be related with the ones of increased exploitation quantities of the global three-large fossil fuels of coal,oil and gas,and the relationship between the events of earth crust expansion getting thermal with the accumulated increasing of the land crust expansion thickness from calculation and the accumulated increasing of fossil fuels being exploited,et al. The three mechanism-modes of earth's epidermis warming over the past 100 years since 1890 from earth interior changes with relation to fossil fuels being exploited were suggested that the weakened release energies of global strong earthquakes caused by the increasing of earth thermal stress energies and overall warming of lithosphere, the "weightlessness" and expansion and getting thermal of continental crust,the increasing of earth currents and heat quantities generated by added origid geological and tectonic activities in mining areas and earth's surface getting thermal. © (2014) Trans Tech Publications, Switzerland. Source


Ma Q.,China University of Mining and Technology
Beijing Ligong Daxue Xuebao/Transaction of Beijing Institute of Technology | Year: 2011

With the decrease of gas pressure in cleat, changes occur in the absolute permeability of coal-bed methane (CBM) reservoirs during primary depletion. To investigate this variation, based on the volumetric balance among the factors of bulk coal, solid grains and pores, how the MATCHSTICK strain changes with pore pressure is studied in this paper first. Furthermore, how permeability varies with the strain changes is researched and then the regularity of permeability changes is proposed. The rationality of applying MATCHSTICK strain changes to analyze permeability is proved by the curves of strain and permeability changes obtained from production field and laboratory. Source


Gao W.-J.,North China Institute of Science and Technology | Shan R.-L.,China University of Mining and Technology
Meitan Xuebao/Journal of the China Coal Society | Year: 2012

The experiments performed on split Hopkinson pressure bar(SHPB)with a large diameter show that the anthracite has a threshold speed 4.3 m/s under impact loading. The threshold value provided the number basis of reference in order to improve anthracite coal lump ratio, and reform the optimization of production system and storage transportation system. Based on the characteristics of measured dynamic curves, anthracite is of distinct plastic yield and strengthen properties, and the initial elastic modulus, yield strength, as well as the ultimate strength go up with strain rate; but there is the best correlation between yield strength and the strain rate. Anthracite failure under impact loading is classified into four patterns: compress-shearing damage, tensile stress damage, extensible strain damage and unloading damage, among them, tensile stress destruction, tensile strain damage and uninstall damage are the main destroy forms. Source


Xu L.-J.,China University of Mining and Technology
Meitan Xuebao/Journal of the China Coal Society | Year: 2012

In order to investigate crushing degree of coal-gangue with different roller structure by squirrelcage selectivity sepatation equipment, a discrete element model was established with particle flow code in two dimensions(PFC 2D) based on soft ball model, and dynamic behaviors of coal-gangue particles were simulated and analysed with different roller structures. The result shows that crushing degree of coal-gangue is moderate with 6 broken rods. Coal-gangue can not break with 9 broken rods, and coal-gangue may severely break with 3 broken rods. It is shown by the comparisons between numerical results and experimental data that they have good consistency. Source


Zhang H.,China University of Mining and Technology | Ouyang S.,Hebei University of Engineering
Energy Exploration and Exploitation | Year: 2014

There are more than 30 waste dumps in the area around Handan city. These waste dumps contain many harmful metals, which may migrate into the soil by raining water. In order to study the migration mechanism and regularity of the harmful metals, a leaching test of the coal gangues was carried out in the laboratory. The results showed that the metal concentrations dissolved out and the release rate from coal gangue were not only related to the pH value of leachate, but also related to the element concentrations in coal gangues. The concentrations of Cr, Mn, Cu, Zn, Pb and Cd in the filter water and collected rainwater were beyond the limits in the Environmental Quality Standards for third Class Surface Water (GB15618-1995). Source


Yang Y.,Nanjing Southeast University | Shen X.,Nanjing Southeast University | Shen X.,China University of Mining and Technology | Zhao P.,Nanjing Southeast University | And 2 more authors.
Optics Express | Year: 2015

It has been demonstrated that an ultrathin uniformly corrugated metallic strip is a good plasmonic waveguide in microwave and terahertz frequencies to propagate spoof surface plasmon polaritons (SPPs) with well confinement and small loss (Shen et al., PNAS 110, 40-45, 2013). Here, we propose a simple method to trap SPP waves on the ultrathin corrugated metallic strips in broad band in the microwave frequencies. By properly designing non-uniform corrugations with gradient-depth grooves, we show that the SPP waves are slowed down gradually and then reflected at predesigned positions along the ultrathin metallic strip when the frequency varies. We design and fabricate the ultrathin gradient-corrugation metallic strip on a thin dielectric film. Both numerical simulation and measurement results validate the efficient trapping of SPP waves in broadband from 9 to 14 GHz. This proposal is a promising candidate for slow-wave devices in both microwave and terahertz regimes. © 2015 OSA. Source


Zhang Q.-F.,Jiangnan University | Wang D.-Q.,China University of Mining and Technology
Yantu Gongcheng Xuebao/Chinese Journal of Geotechnical Engineering | Year: 2012

Through physical model tests on colliery wastes improved by dynamic compaction, the dynamic strain gauge DH5939 is used to record the induced dynamic stress. The distribution and rules of the dynamic stress at different depths under different impact loadings and numbers of dynamic compaction are studied. It is shown that the dynamic stress has a single peak, and it has a significant decay to reach the peak under the impact loadings along the depth of the hammer. The decay speed of the horizontal dynamic stress is faster than that of the vertical one, and the range of influence of the vertical dynamic stress is more extensive than that of the horizontal one. The peak value of the dynamic stress attenuates quickly with the depth and similar in an approximate way of negative exponential decay law under the same tamping energy. In addition, for different measuring points, with the increase of compaction number, the dynamic stress tends to be stable after three to six blows. It may provide an efficient way to analyze the mechanism of dynamic compaction. Source


Chen Z.H.,China University of Mining and Technology
Applied Mechanics and Materials | Year: 2014

To solve the problem of underground tunneling face from the empty top, using FLAC3D analysis software, surrounding rock stability for coal roadway 2-1121 of Ganhe Coal Mine are analyzed in numerical calculation. (1) During the tunneling, distance drivage face head-on 0.5-1m at the roof of roadway deformation and destruction features are more obvious, the two sides of roadway are even more significant. (2) Ganhe Coal Mine roof deformation has been established with different empty the experience formula of the zenith distance, obtained Ganhe underground tunneling face reasonable empty zenith distance is 3.5m. (3) Temporary support can obviously reduce roof deformation, reduce thickness of plastic zone of the top, to improve the stability of surrounding rock tunneling faces. © (2014) Trans Tech Publications, Switzerland. Source


Yang J.,China University of Mining and Technology
Zhongguo Jixie Gongcheng/China Mechanical Engineering | Year: 2014

Aiming at the demands to control the decomposing granularity of function surface in the process of the growth design, function mode was used to express the product geometric structure information based on its geometric property, which was also used as the carrier to integrate product manufacturing process information. So the manufacturing information model was built based on function surface. The theory of information entropy was introduced to quantify the model information. The minimum value of conceptual product manufacturing information entropy was used as the control target of function surfaces decomposing granularity to determine whether to stop the growth of conceptual product or not. The correctness of the theory was verified through the specific product design experiments. Source


Zhang J.,China University of Mining and Technology
Procedia Engineering | Year: 2011

The prediction model for gas content in coal seam has been built based on the BP Neural Network to predict gas content accurately. And the model has been solved and forecasted by combining MATLAB programming with actual data. Moreover, the comparison analysis has been performed with the traditional prediction model based on multipleregression. The results show that the non-linear gas content model related with basement buried depth and coal seam thickness etc could be established by utilizing the BP Neural Network. And its prediction accuracy and feasibility are better than the multiple-regression model. It is an ideal model for predicting gas content. It could provide some new ideas for the gas content prediction and the prevention and control for coal and gas outburst. © 2011 Published by Elsevier Ltd. Source


Zhu J.B.,Ecole Polytechnique Federale de Lausanne | Zhao G.F.,University of New South Wales | Zhao G.F.,China University of Mining and Technology | Zhao X.B.,Nanjing University | Zhao J.,Ecole Polytechnique Federale de Lausanne
Computers and Geotechnics | Year: 2011

A validation study of the distinct lattice spring model (DLSM) for wave propagation problems is performed. DLSM is a microstructure-based numerical model, which is meshless and has advantages in modelling dynamic problems where stress wave propagation is important. To verify the applicability of DLSM to modelling wave propagation through a discontinuous medium, the virtual wave source (VWS) method is used to obtain analytical solutions for wave propagation across a jointed rock mass. Numerical modelling results of the commercial code UDEC are selected as the reference. The effects of particle size and lattice rotation angle on wave propagation are first studied. Then, the results of wave transmission across a single joint with a different joint stiffness and across multiple parallel joints with different joint spacings are derived with DLSM, UDEC and VWS. These results are in good agreement with each other. Therefore, the capability of DLSM to model P-wave propagation across jointed rock mass is verified, which provides confidence for the further application of DLSM to modelling more complex problems. © 2010 Elsevier Ltd. Source


Zhu S.,China University of Mining and Technology | Zhu S.,Huazhong University of Science and Technology | Shen Y.,Huazhong University of Science and Technology
Neurocomputing | Year: 2011

In this paper, the problem of passivity analysis is investigated for a class of stochastic delayed neural networks with Markovian switching. By applying Lyapunov functional and free-weighting matrix, delay-dependent/independent passivity criteria are presented in terms of linear matrix inequalities. The results herein include existing ones for neural networks without Markovian switching as special cases. An example is given to demonstrate the effectiveness of the proposed criteria. © 2011 Elsevier B.V. Source


Yan X.,China University of Petroleum - East China | Yan X.,Pennsylvania State University | Yan X.,China University of Mining and Technology | Komarneni S.,Pennsylvania State University | And 2 more authors.
Microporous and Mesoporous Materials | Year: 2014

As prepared MOF Cu3(BTC)2 was immersed into different kinds of solvents with or without inorganic salt. The as-treated samples were characterized by XRD, SEM, FT-IR, TG, and N2 physisorption techniques. The results showed that CO2 uptake of the sample treated by ethanol and ammonium chloride at 65 C showed very high CO2 adsorption capacity of 11.6 mmol/g at 273 K and 1 atm CO2 pressure, which is a drastic increase of 61% compared to the original MOF sample. The selectivity of CO2 over N2 and CH4 was also improved after chemical treatment. The sample as a CO2 adsorbent also exhibited good cyclic stabilities. © 2013 Elsevier Inc. All rights reserved. Source


Guo S.-D.,China University of Mining and Technology | Guo S.-D.,CAS Institute of Physics | Liu B.-G.,CAS Institute of Physics
Physica B: Condensed Matter | Year: 2013

We investigate the electronic structures of the cubic and tetragonal phases of Sr2MgWO6. Calculated electronic structures show that the two phases are both wide indirect band gap semiconductors. Our phonon calculations indicate that the structural phase transition from cubic to tetragonal phase is because the phonon frequencies of Γ4+ modes become imaginary. Our variable cell-shape relaxation results imply that a symmetry-allowed intermediate trigonal phase could be realized. © 2012 Elsevier B.V. All rights reserved. Source


Miao X.-X.,China University of Mining and Technology
Meitan Xuebao/Journal of the China Coal Society | Year: 2012

On the basis of a brief overview of mining with backfilling history and the objectives, requirements and difficulties of developing modern mining with backfilling technology, this paper systematically introduced the research progress of fully mechanized mining with solid backfilling technology, focused on the expounding the strata movement theory of mining with dense backfilling, including equivalent mining height theory of strata movement control, continuous media mechanics model of strata movement, calculation formula of strata movement, and stope rock pressure and support stress analysis, which are the prerequisites of the new technology. And then detailedly introduced the system, equipments and technics of fully mechanized mining with solid backfilling technology, and the engineering examples of large-scale mining with backfilling under dense buildings, island village coal pillar, near the loosen aquifer and under the large embankment. Source


Wu Q.,Heilongjiang Institute of Science and Technology | Zhang Q.,Heilongjiang Institute of Science and Technology | Zhang B.,Heilongjiang Institute of Science and Technology | Zhang B.,China University of Mining and Technology
Safety Science | Year: 2012

The growth rate of hydrate and morphology of methane hydrate formation were studied in a visual pressure cell at 5.5MPa. The gas hydrate formation was carried out (coal mine methane (CMM)+tetrahydrofuran (THF)+sodium dodecyl sulphate (SDS)+H 2O) with and without SAP. Experimental data on the hydrate growth rate and induction time were obtained for three different CMM samples. The influence of SAP on hydrate growth rate was determined. Results showed that after the addition of SAP, with the methane concentration increased in CMM, the induction time was reduced by 9min, 10min and 3min, and the growth rate was shortened by 0.56×10 -6/m 3min -1, 0.53×10 -6/m 3min -1 and 1.42×10 -6/m 3min -1, respectively. This study could be useful for the recovery of methane from CMM by forming hydrate in the chemical and mining industry. © 2011 Elsevier Ltd. Source


Jia M.-K.,China University of Mining and Technology | Jia M.-K.,Jiaozuo Coal Company
Caikuang yu Anquan Gongcheng Xuebao/Journal of Mining and Safety Engineering | Year: 2012

According to the geological condition of buried deep with thin bedrock coal seam in the 11011 working face of Zhao-Gu No.1 coal mine, the paper discussed the conditions of thin bedrock water gushing and running sand coal seam by using the coal mine field investigating and statistical analysis method. After analyzing and calculating the working face roof's structure instability mode by using the theories of 'masonry beam' and 'step beam' we have analyzed the overlying strata damage, migration evolution rule of fractures. The results show that and the height of the working face roof water fracture zones is about 48 m. Therefore, some preventive suggestions and measures have to been taken into practice when mining a coal within such a range. The measures can also guide other coal mines with similar geological condition. Source


Liu K.,China University of Mining and Technology
Beijing Ligong Daxue Xuebao/Transaction of Beijing Institute of Technology | Year: 2012

In order to provide the technical aid for chemical leakage accidents in factory, taking the zone of benzene tank in He'nan Shenma Nylon Chemical Co. as a sample, the heavy gas dispersion model and turbulence flow model were used to simulate leakage of benzene tank under the constrain of basic assumptions. The gas concentration contours with the change of wind velocity were analyzed and the safety zones were determined. The results of simulation show that the bands of diffused puff are formed along the direction of tailwind and the rate of vertical or horizontal proliferation is equal in mixed layer. For different wind speeds, appropriate protective measures should be taken to control the results of accident. The achieved visual simulation and function of onsite data management provide the technical support for the leak accident of benzene tank. Source


The relationship between stress and drill cutting weight (DCW) is studied with numerical modeling and field testing. Jinjiazhuang coal mine 110403 workface is used as a case study. Stress analysis of the workface is carried out with numerical modeling, with input parameters obtained from laboratory experiments. The stress of workface is examined at one section along the mining direction in terms of the stress distribution. Comparing simulating results of stress and field testing drill cutting weight, the stress and drill cutting weight has good agreement and one formulation is derived in this case. © 2011 Elsevier Ltd. Source


Liu Z.,China University of Mining and Technology
Journal of Materials in Civil Engineering | Year: 2015

The objective of the present study was to investigate the engineering characteristics of polyester-reinforced cement-stabilized macadam (PETCSM). Shrinkage and mechanical tests were performed to analyze the water loss rate, shrinkage coefficient, compressive strength, cleavage strength, and compression rebound modulus of PETCSM as functions of the age and fiber content of the material. An optimum fiber content of PET was proposed. The effects of PET were compared with those of polypropylene (PP) fibers. As the fiber content increased, the water loss rate of PETCSM decreased and then increased, with the minimum water loss occurring at a fiber content of 0.7‰. The shrinkage coefficient of the PETCSM gradually decreased as the fiber content increased, with the critical point of zero shrinkage appearing when the fiber content reached 0.7‰. The PET fibers had a greater effect on enhancing the mechanical performance of the CSM than did the PP fibers. The strength of the PETCSM was primarily affected by the maturity of the hydration reaction, by active enhancement effects, and by the passive blocking effects of the fibers. The strength was also affected by the fiber age and fiber content. The cleavage strength was more sensitive to the fiber content than was the compressive strength. The addition of PET altered the elastoplastic behavior of the PETCSM and significantly decreased shrinkage in the CSM. The optimum fiber content in the PETCSM is 0.7‰. The PETCSM has better engineering properties than CSM without fiber. This paper may provide a solid theoretical foundation for the widespread use of PETCSM in engineering applications. © 2015 American Society of Civil Engineers. Source


Chai Y.,China University of Mining and Technology
Lecture Notes in Electrical Engineering | Year: 2011

This paper made detail research on fuzzy logic system and neural network, and set up dynamic fuzzy neutal network (FNN) prediction model for serious coal and gas accident. The model can express qualitative knowledge, and also has self-learning function and ability to deal with qualitative knowledge. The paper verified the feasibility of the model by simulation experiment and realized prediction of serious coal and gas accident. © 2011 Springer-Verlag Berlin Heidelberg. Source


Yang T.-P.,China University of Mining and Technology
Lecture Notes in Electrical Engineering | Year: 2014

In order to simplify vectors selection and function time calculation, increase the DC bus voltage utilization ratio and expand the operation range of induction machines; this chapter proposes a new SVPWM algorithm and the control strategy in the over-modulation section. In the new algorithm the coordinate transformation is not necessary. DSP2335 and FPGA are adopted in the experiment and the results prove the feasibility of the algorithm even in the over-modulation region. © 2014 Springer Science+Business Media New York. Source


Liu J.,Tsinghua University | Han R.,Tsinghua University | Zhao Y.,Tsinghua University | Wang H.,Tsinghua University | And 3 more authors.
Journal of Physical Chemistry C | Year: 2011

A new route to synthesize V-doped and V-N codoped titania nanocatalysts using a novel two-phase hydrothermal method applied in hazardous PCP-Na decomposition was reported. The physicochemical properties were characterized, indicating that the crystallite surface area increased after both first hydrothermal (FH) V impregnation and second hydrothermal (SH) N implantation, whereas mesoporous framework shrinkage and enlargement resulted from FH and SH, respectively. ICP and EPR demonstrated that SH did not alter V content, but rather it induced paramagnetic V4+ increase. The V species was enhanced from the inner to the catalyst surface with V5+ as the dominant mode and the N dopant existed with substitutional nitrogen as the main structure. The optical red shift by low vanadium implantation was ascribed to the V2p state, mainly from V4+ species in the matrix. After SH incorporation, the substitutional N1s state, interstitial N-O state, and concomitant NOx were responsible for the strong visible absorption of V-N-TiO2. The photodegradation rates of PCP-Na by the remodified catalysts after SH were much larger than that of the mono-V-TiO2 precursors fabricated in FH. SHNV02, SHNV05, and SHNV10 exhibited 2.4, 1.6, and 3.1 times promotion toward PCP-Na decomposition, respectively. Moreover, other variations and the synergetic effects after two-phase treatments were adequately discussed and proven to be useful in facilitating photocatalytic promotion. This work provided a strategy for obtaining further enhancement of the synthesized catalyst by second-step modification to achieve the deep removal effect of contaminants. © 2011 American Chemical Society. Source


Guo J.-W.,China University of Mining and Technology | Guo J.-W.,Energy Chemical Industry Research Institute
Meitan Xuebao/Journal of the China Coal Society | Year: 2012

Aimed at the stability of surrounding rock in Pingdingshan Coal Mine, took a typical deep roadway with joint fissured surrounding rock as study object, used discrete element numerical simulation, simulated the deformation and failure mechanism of surrounding rock, and the control technologies of joint fissured surrounding rock roadway were proposed. The results show that the tensile failure appears at vault and two side-walls and in the middle of floor at first. Then, the shear failure appears at spandrel and two base angles. The failure zone extends into the deep area until the roadway is instable. According to the in-situ monitor data, it is concluded that the stress in anchor and cable tends to be stable after supporting for two months, as well as the horizontal convergence, vault subsidence and floor heave. It means that the supporting technology works and the stability of soft surrounding rock in deep rock roadway is controlled. Source


Chen S.-Z.,China University of Mining and Technology
Meitan Xuebao/Journal of the China Coal Society | Year: 2012

Based on the need of mobile crusher semi-continuous mining system application in large open pit mines, this dissertation comprehensively applied surface mining theories, mining engineering system theories, technology economics theories, as well as computer technology. Through investigation researches, theoretical analysis and spot engineering practice, the dissertation researched on crushing equipment selection, structure optimization, determination of crusher locations and shifting distance, as well as the application of stripping semi-continuous technology system. Based on the results of previous studies, the dissertation summarized the classification of crusher and the concepts of all kinds crushers in this dissertation. With the aim of open pit profit maximization, this study established a two-grade crusher comprehensive optimization model. In addition, according to the needs of stripping semi-continuous technology system used in open pit coal mine, the crushing characteristics and suitable crusher type of the high moisture content and easily bond material were analyzed. This dissertation present a view of modular crusher station as well as to improve the flexibility, reliability, and local production ratio of the crusher station, and to improve the working environment. Based on these, the dissertation established the parameter optimization model of feed hopper structure. This dissertation showed the previous research results on truck-shovel match of shovel truck discontinuance technology system, and analyzed the characteristic of truck transport under mobile crusher station semi-continuous mining system. Targeting the lowest system production cost the dissertation established the optimization model of truck type. According to the characteristics of mobile crusher locate in pit, this dissertation analyzed the affect factors and established the optimization model of crusher station location optimization model and shifting distance optimization model. The dissertation also introduced the transport distance increase coefficient k into the optimization model to embody the influence of belt conveyor transport system of the lower level to the internal dumping distance of upper levels. According to the need of stripping semi-continuous technology system application and the characteristics of mobile crusher, the dissertation established service areas model of open pits semi-continuous mining system, group bench mining model and strip width optimization model in this dissertation. These models provided the basis for service areas and mining parameters determination of stripping semi-continuous technology system. In order to meet the needs of stripping semi-continuous technology system application with mountain slope dumping area, system characteristics, link structure, application conditions and economic efficiency of discontinuous-continuous-discontinuous form semi-continuous technology system were analyzed in this dissertation. In order to improve the belt conveyer efficiency, the dissertation presented combined system that crusher and bucket wheel excavator use the same transport system, and four kinds crusher station location have been compared. The author verified the practicality of models established in this dissertation through case studies. Source


Meng Z.-P.,China Three Gorges University | Meng Z.-P.,China University of Mining and Technology | Hou Q.-L.,University of Chinese Academy of Sciences
Meitan Xuebao/Journal of the China Coal Society | Year: 2012

Adopted samples from the high-rank coal reservoirs in Southeast margin of Ordos Basin, through the stress sensitivity experiment of coal samples, stress sensitivity of coal reservoirs and the effects of effective confining pressure, fractures inside the coal and water condition on stress sensitivity were analyzed. The results show that, the permeability decreases according to negative exponential function with the increase of effective stress. When effective stress changes from 2.5 MPa to 10 MPa, dimensionless permeability of the coal samples is 0.10~0.28, and the average value is less than 0.15; the damage rates of permeability are 71.92%~90.14%, and the average value is 84.59%. When effective stress is less than 5 MPa, the coal reservoir permeability decreases rapidly with the increase of the effective stress, the stress sensitivity is the highest; when effective stress is between 5 MPa and 10 MPa, the stress sensitivity is medium; when effective stress bigger than 10 MPa, the decline of the permeability slow down, and the stress sensitivity is weak. The initial permeability of coal samples with fractures inside is higher, and the stress sensitivity is relatively small; the irreversible plastic deformation generated larger in the lifting-pressure process results in relatively high irreversible damage rates after the pressure decreas. The permeability of wet coal samples reduces rapidly with the increase of effective pressure, with the increase of moisture content, the stress sensitivity is more obvious. Source


Zhang S.,China University of Mining and Technology
Computers and Mathematics with Applications | Year: 2010

In this paper, we consider the existence of positive solutions to the singular boundary value problem for fractional differential equation. Our analysis relies on a fixed point theorem for the mixed monotone operator. © 2009 Elsevier Ltd. All rights reserved. Source


Zhai W.-G.,China University of Mining and Technology
Fangzhi Gaoxiao Jichukexue Xuebao | Year: 2014

The ways of expressing n as a sum of consecutive integers (or positive integers) is studied. For each natural number n, it is showed that if we know all odd divisor of n, then we can get all ways of expressing n as a sum of consecutive integers(or positive integers). The mean value of the number of such expressions is also investigated. Source


Liu L.,China University of Mining and Technology | Ni X.L.,Beijing Institute of Technology | Yin H.Q.,University of Science and Technology Beijing | Qu X.H.,University of Science and Technology Beijing
Journal of the European Ceramic Society | Year: 2015

The mouldability of various zirconia micro gears was investigated based on different binder systems. Temperature window for feedstock preparation and injection moulding was set up based on thermal analysis. Rheological properties of the feedstocks and injection moulded micro gears of different dimensions (200 to 900. μm) were examined to study the mouldability. Experimental results show that the micro gears below 500. μm were difficult to mould due to sticking and short-shot. As the low-molecule binder component, bee wax (BW) provided the feedstock with better fluidity and stability than paraffin wax (PW) to replicate the small mould. As the backbone polymer, a combination of ethylene-vinyl acetate (EVA) and high-density polyethylene (HDPE) was beneficial to mould filling and demoulding. The micro gears as small as 200. μm were injection moulded and sintered with shape retention using the feedstock comprising the binder system of HDPE, EVA, BW and stearic acid. © 2014 Elsevier Ltd. Source


Wang Z.,China University of Mining and Technology | Wang N.,Jiangsu University of Science and Technology
Expert Systems with Applications | Year: 2012

This study investigates the quantitative relationship between knowledge sharing, innovation and performance. Based on the literature review, we develop a research model positing that knowledge sharing not only have positive relationship with performance directly but also influence innovation which in turn contributes to firm performance. This model is empirically tested using data collected from 89 high technology firms in Jiangsu Province of China. It is found that both explicit and tacit knowledge sharing practices facilitate innovation and performance. Explicit knowledge sharing has more significant effects on innovation speed and financial performance while tacit knowledge sharing has more significant effects on innovation quality and operational performance. © 2012 Elsevier Ltd. All rights reserved. Source


Zhu S.,China University of Mining and Technology | Shen Y.,Huazhong University of Science and Technology
Neural Computing and Applications | Year: 2013

In this paper, we analyze the robustness of global exponential stability of neural networks with Markovian switching (NNwMS) subject to random disturbances or time-varying delays. Given a globally exponentially stable neural network with Markovian switching, the problems to be addressed herein are how much noises or time delays that the neural networks can remain to be globally exponentially stable. We characterize the upper bounds of the time delays or noise intensity for the NNwMS to sustain global exponential stability. Two numerical examples are provided to illustrate the theoretical results. © 2012 Springer-Verlag London Limited. Source


Chen H.,China University of Mining and Technology | Gu J.J.,Dalhousie University | Gu J.J.,Shandong University
IEEE/ASME Transactions on Mechatronics | Year: 2013

This paper describes the developed three-phase 6/8 poles switched reluctance external rotor motor drive for a fan in air conditioner. The external rotor core structure and the internal stator core structure, the three-phase windings arrangement, the slotted claw, and the setting structure of the photoelectric transducers on the rotor position detector are illustrated. The electromagnetic field calculation results are given. The three-phase asymmetric bridge power converter was used in the drive system. The block diagram of the switched reluctance external rotor motor drive with closed-loop rotor speed control is given. The closed-loop rotor speed control is implemented using a fuzzy logic algorithm. The experimental tests of the developed prototype are made for driving the fan from 200 to 950 r/min. The comparison results of the two systems show that the input power and input phase current RMS value are lower in the developed three-phase 6/8 poles external rotor switched reluctance motor drive prototype with the fan than those in the induction motor variable-frequency variable-speed drive with the fan. © 1996-2012 IEEE. Source


Zou Z.,China University of Mining and Technology
Applied Mechanics and Materials | Year: 2012

This paper using low-pressure pre-mixed abrasive water jet to cutting composite material,testing and verifying feasibility of the low pressure abrasive water jet cutting, analyzes the abrasive waterjet working parameters on cutting of influence which performance level and interaction effect. © (2012) Trans Tech Publications, Switzerland. Source


Wang X.,China University of Mining and Technology
Archives of Mining Sciences | Year: 2015

For coal mine ground control issues, it is necessary to propose a failure criteria accounting for the transversely isotropic behaviors of rocks. Hence, it is very helpful to provide experimental data for the validation of the failure criteria. In this paper, the method for preparing transversely isotropic specimens and the scheme of the Brazilian tensile strength test are presented. Results obtained from Brazilian split tests under dry and water-saturated conditions reflect the effect of the development direction β of the structural plane, such as the bedding fissure, on the tensile strength, ultimate displacement, failure mode, and the whole splitting process. The results show that the tensile strength decreases linearly with increasing β. The softening coefficient of the tensile strength shows a sinusoidal function. The values of the slope and inflection point for the curve vary at the different stages of the Brazilian test. The failure mode of the rock specimen presented in this paper generally coincides with the standard Brazilian splitting failure mode. Based on the test results, the major influencing factors for the Brazilian splitting strength are analyzed and a mathematical model for solving the Brazilian splitting strength is proposed. The findings in this paper would greatly benefit the coal mine ground control studies when the surrounding rocks of interest show severe transversely isotropic behaviors. © 2015 Archives of Mining Sciences. Source


Ma J.,Tianjin University | Tu H.,Tianjin University | Tu H.,China University of Mining and Technology
Nonlinear Dynamics | Year: 2014

Considering the macroeconomic model of money supply, this paper carries out the corresponding extension of the complex dynamics to macroeconomic model with time delays. By setting the parameters, we discuss the effect of delay variation on system stability and Hopf bifurcation. Results of analysis show that the stability of time-delay systems has important significance with the length of time delay. When time delay is short, the stable point of the system is still in a stable region; when time delay is long, the equilibrium point of the system will go into chaos, and the Hopf bifurcation will appear in certain conditions. In this paper, using the normal form theory and center manifold theorem, the periodic solutions of the system are obtained, and the related numerical analysis are also given; this paper has important innovation- theoretical value and acts as important actual application in macroeconomic system. © 2013 Springer Science+Business Media Dordrecht. Source


Yang X.,Shanghai EAGTOP Electronic Technology Co. | Gao F.,China University of Mining and Technology
Communications in Computer and Information Science | Year: 2011

A new possible modeling for the local fractional iteration process is proposed in this paper. Based on the local fractional Taylor's series, the fundamentals of local fractional iteration of the continuously non-differentiable functions are derived from local fractional calculus in fractional space. © 2011 Springer-Verlag. Source


Liu X.,China University of Mining and Technology | Yin Z.,Sun Yat Sen University
Mathematical Methods in the Applied Sciences | Year: 2014

We consider a generalization of Camassa-Holm-type equation including the Camassa-Holm equation and the Novikov equation. We mainly establish the existence of solutions in lower order Sobolev space Hs(ℝ) with 1 Source


Shi Q.,South China University of Technology | Peng F.,South China University of Technology | Liao S.,South China University of Technology | Wang H.,South China University of Technology | And 4 more authors.
Journal of Materials Chemistry A | Year: 2013

Carbon materials have received an increasing amount of attention due to their low cost, long-term stability, and high electrocatalytic activity in catalyzing the cathodic oxygen reduction reaction (ORR). However, most of the carbon catalysts have exhibited their excellent activity only in alkaline media, which greatly hinders their practical application in polymer electrolyte membrane fuel cells (PEMFCs). In order to break the restriction of alkaline conditions, sulfur and nitrogen doped carbon nanotubes (SN-CNTs) were designed and successfully prepared via annealing of a mixture composed of nitrogen doped carbon nanotubes (N-CNTs) and sulfur. The result showed the as-prepared SN-CNTs have an enhanced ORR activity in both acidic and alkaline media compared with N doped CNTs (N-CNTs). This report also provides a new approach to explore low-cost electrocatalysts for practical fuel cell applications. © 2013 The Royal Society of Chemistry. Source


Fan H.,China University of Mining and Technology | Liu X.,Wuhan University
Mathematical Methods in the Applied Sciences | Year: 2014

In this paper, we study the multiplicity results of positive solutions for a semi-linear elliptic system involving critical growth terms. With the help of Nehari manifold and Ljusternik-Schnirelmann category, we investigate how the coefficient h(x) of the critical nonlinearity affects the number of positive solutions of that problem and get a relationship between the number of positive solutions and the topology of the global maximum set of h. © 2014 John Wiley and Sons, Ltd. Source


Fan H.,China University of Mining and Technology | Liu X.,Wuhan University
Mathematical Methods in the Applied Sciences | Year: 2014

In this paper, we study the existence of multiple positive solutions for a degenerate nonlocal problem on unbounded domain. Using the Ekeland's variational principle combined with the mountain pass theorem, we show that problem admits at least two positive solutions under several different conditions. © 2014 John Wiley and Sons, Ltd. Source


Jin C.,Soochow University of China | Yang Z.,China University of Mining and Technology | Cao X.,Soochow University of China | Lu F.,Soochow University of China | Yang R.,Soochow University of China
International Journal of Hydrogen Energy | Year: 2014

Ba0.9Co0.5Fe0.4Nb0.1O 3 (BCFN) perovskite has been synthesized by a solid-state reaction method, and characterized by XRD, SEM, BET. This oxide has a porous structure and a specific surface area of 10.24 m2 g-1 after ball-milled 24 h. The catalytic activity of the oxide for the oxygen reduction reaction (ORR) and the oxygen evolution reaction (OER) in 0.1 M KOH solution has been studied by using a rotating ring-disk electrode (RRDE) technique. RRDE results show that the ORR mainly favors a direct four electron pathway, and a maximum cathodic current density of -5.70 mA cm-2 at 2500 rpm was obtained, which is close to that of Pt/C (20 wt.% Pt on carbon) electrocatalyst in the same testing conditions. Compared with behaviors of pure C and Pt/C electrode, a lower onset potential of BCFN for OER is observed, and a bigger anodic current at the same applied potential is obtained. Considering small surface area of the BCFN catalyst, a big overpotential is given in the discharge-charge curves. However, the outputs of 2032 coin Li-air batteries in a dry gas mixture composed of 80 vol.% pure N2 and 20 vol.% pure O2 demonstrated that BCFN could be a potential bifunctional catalyst for the Li-air battery. © 2013, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights. Source


Dong C.,China University of Mining and Technology
Geophysical Prospecting for Petroleum | Year: 2013

Lithologic reservoir exploration requires seismic data with high resolution, SNR and fidelity. However, over emphasis on resolution improvement inevitably decreases data fidelity. Through the comparison of seismic processing steps and results of two three-dimensional seismic data in neighboring survey of D1j and D2jb, the difference reveals that post-stack frequency-enhancement processing causes the decline of data fidelity and analyzes the geological recognition difference caused by fidelity damaged seismic data. We also proposed to introduce pure wave seismic data as a basis for processed data fidelity testing. Source


Cui J.,Ningbo University of Technology | Li Y.,Taiyuan University of Technology | Du Z.,Ningbo University of Technology | Meng Q.,Taiyuan University of Technology | Zhou H.,China University of Mining and Technology
Journal of Materials Chemistry A | Year: 2013

Through calculating the band structures of the defect chalcopyrite semiconductor Cu1-xGaSbxTe2 with the proper addition of Sb to CuGaTe2, we have demonstrated that Sb actually mostly occupies the Te rather than Cu lattice sites. Such a dominant occupation increases the density of states (DOS) at the Fermi level and the effective mass of the valence band, and thereby results in an increase in the Seebeck coefficient. The electrical conductivity (σ) is hardly related to Sb content when x < 0.1, due to the subtle change in the concentration n and mobility μ at the degenerate state of holes. The attempted addition of Sb causes a decrease in the lattice thermal conductivity (κL), but as the Sb content increases there is a limited enhancement of κL. We have thus determined the mechanism, proposing that the dual effect on the κL resulted from the extra lattice mismatch and crystal structure distortion. By considering all the effects mentioned above on the transport properties, we have attained the highest thermoelectric ZT value (1.07 ± 0.1) of the sample Cu1-xGaSbxTe 2 (x = 0.02) at 721 K, which shows promise for application in the intermediate temperatures. This journal is © 2013 The Royal Society of Chemistry. Source


Sun J.-P.,China University of Mining and Technology
Meitan Xuebao/Journal of the China Coal Society | Year: 2011

A method of preventing escape tunnel from being blocked was presented: build not less than 3 roadways so as to decrease the probability of all escape channels blocked; make sure of no mechanical & electrical equipment existing in ventilation roadway to reduce fire source of detonating gas; ventilation roadway should not play the role of walkway in order to reduce human casualties caused by gas explosion. Put forward a method of relay escape with oxygen breathing apparatus: install refuge chambers which have oxygen breathing apparatus every certain distance in escape channels. A method of naturally reducing temperature of refuge chambers was proposed: refuge chambers can be cooled down by coal & rock around them when the coal & rock which form the refuge chambers are at lower temperature. In this case, refuge chambers don't need installed refrigeration equipment and insulation-treatment. Refrigeration and cooling equipment is unnecessary for refuge chambers which connected with ground through hole, such refuge chambers should be cooled down by supplying air from ground. For the purpose of not only adding a escape tunnel, but also contribute to cooling down the temperature by air come from ground. The diameter of hole which connected refuge chambers with ground should be 700 mm. Raised a method of arranging pipeline which has a strong ability of anti-disaster: the electric cables and optical cables in monitoring system, personnel position system, communication system, and the pipelines in compressed-air self-help system, water rescue system should be all buried in channel. A method of constructing refuge chambers with no compressed air spray was brought forward. Put forward emergency refuge system in undergroundcoal mine which composed of oxygen breathing apparatus, compressed oxygen self-rescuers, escape channels, refuge chambers, escaping routes and indications, emergency plan. Source


Zhang K.-X.,China University of Mining and Technology
Meitan Xuebao/Journal of the China Coal Society | Year: 2011

For geological conditions of specific production of the deep coal seams roadway driving along next goaf, using the methods of theoretical analysis, numerical calculation and the combination of field and test, obtaining certain method of reasonable width of chain pillar of deep coal seams roadway driving along next goaf, which considering five aspects for the pillar width from distribution of stress of the section of the lateral support goaf, stress distribution of coal pillars, surrounding rock stress distribution, the relationship between deformation of surrounding rock and coal pillar width and the theoretical of the width of pillar, in particular, with the full consideration of the influence of the lower coal mining on the retain of the width size of the pillar upper roadway driving along next goaf. Field test results show that: the method of determining the coal pillar width is science and reliable, which provide a scientific basis for the reasonable width of deep coal seams roadway driving along next goaf pillar, improving difficult situation of deep roadway maintenance and raising coal mining rate. Source


Yin S.,Wuhan University of Technology | Yin S.,China University of Mining and Technology | Mu S.,Wuhan University of Technology | Pan M.,Wuhan University of Technology | Fu Z.,Wuhan University of Technology
Journal of Power Sources | Year: 2011

Pt nanoparticles supported on TiB 2 conductive ceramics (Pt/TiB 2) have been prepared through a liquid reduction method, where the TiB 2 surfaces are stabilized with perfluorosulfonic acid. The prepared Pt/TiB 2 catalyst is characterized with X-ray diffraction (XRD) and TEM techniques, and a rotating disk electrode (RDE) apparatus. The Pt nanoparticles are found to uniformly disperse on the surface of the TiB 2 particles with narrow size distribution. The electrochemical stability of Pt/TiB 2 is evaluated and found highly electrochemically stable compared to a commercial Pt/C catalyst. Meanwhile, the catalyst also shows comparable performance for oxygen reduction reaction (ORR) to the Pt/C. The mechanism of the remarkable stability and comparable activity for ORR on Pt/TiB 2 is also proposed and discussed. © 2011 Elsevier B.V. Source


Liu T.,China University of Mining and Technology
Meitan Xuebao/Journal of the China Coal Society | Year: 2011

In order to resolve the problems of ventilation and methane, put forward increasing mining height based on comparison of ventilation cross-sections of powered supports with different mining heights. Numerical simulation was applied to research influence of mining height on methane gushing. Results show that larger mining height will increase ventilation cross-section and reduce methane concentration. Aiming at the actual condition of one mine, it obtained rational mining height for the mine with meeting the precondition of coal-wall stability. The application shows that increasing mining height is favorable for safety and high-efficiency of full-mechanized caving mining face. Source


Xia Q.,China University of Mining and Technology
Zhongguo Kuangye Daxue Xuebao/Journal of China University of Mining and Technology | Year: 2013

The paper used Haken model of Synergetics in self-organization theory to study the evolution of modern service industry, based on the investigation of the self-organizing feature of the modern service industry system. At first, the paper analyzed the order parameter and control variables for modern service industry's evolution by adiabatic elimination method and built the evolution model of modern service industry. Secondly, after the model solving through panel data analysis methods, trend function of the evolution was constructed, and the process and discipline of modern service industry's evolution was simulated. From the analysis of control variables in the model, it is easy to conclude that the labor productivity in the chosen variables represents the technology progress and innovation, and is the conducted order parameter in the evolution of modern service industry. And at the same time, labor productivity and investment rate could interact with each other. So they are both the main influencing factors of the evolution, which exist the feedback mechanism of system evolution. Source


Shen X.,Nanjing Southeast University | Shen X.,China University of Mining and Technology | Jun Cui T.,Nanjing Southeast University
Applied Physics Letters | Year: 2013

We propose a planar plasmonic metamaterial on thin corrugated metal films in microwave and terahertz frequencies. From theoretical simulation and experiment, we show that spoof surface plasmon polaritons (SPPs) can propagate along a thin metal film by corrugating its edge with periodic array of grooves. We demonstrate that such a planar plasmonic metamaterial can sustain highly localized SPPs along two orthogonal directions. We have designed and simulated a planar ring resonator in the terahertz frequency, and made experiment in the microwave frequency, both of which exhibit excellent performance. The proposed planar plasmonic metamaterials can play important roles in integrated plasmonic circuits and systems. © 2013 AIP Publishing LLC. Source


Wang J.,China University of Mining and Technology
Meitan Xuebao/Journal of the China Coal Society | Year: 2015

In order to further validate the gas emission from coal particles following the Darcy's law, the coal particles including spherical particle, cylindrical coal particles were investigated. According to the Darcy's law and Fick's law, the mathematical model of gas emission from cylindrical coal particles was also built, which was disposed with finite difference method. A computer software was designed using Visual Basic to solve the mathematical model. Through comparing the simulation results with the experimental results, the conclusion shows that the Darcy's simulation results better match the experimental results than that of Fick's. Also, the comparative study of cylindrical and spherical coal particles shows that gas desorption accumulated amount along with time and coal particle shapes have no direct relationship. Therefore, the gas emission from the coal particles obeys the Darcy's law. ©, 2015, China Coal Society. All right reserved. Source


Sun J.-P.,China University of Mining and Technology
Meitan Xuebao/Journal of the China Coal Society | Year: 2011

The construction principles of the refuge chamber and rescue capsule underground the coal mine were presented. It includes no excessive output and excessive capacity power supply, no issues in safety, no influence with mine ventilation and safety production, responding the emergency quickly, maintenance-free or easily do it, economical and practical, etc. The survival section and device section in rescue capsule should not be separated, and the rescue capsule should not be built in tunnel. Several small or medium size refuge chambers and rescue capsules should be distributed within the specific region. The refuge chamber and rescue capsule should adopt high pressure gas expansion refrigeration; the air blower should adopt air power fan; it should use water of condensation to remove damp at the heat exchanger's surface of refrigeration system; it should use compressed oxygen to supply oxygen; it should not adopt storage battery or external power to supply illumination system. It should equip with the portable detectors which detect O2, CO, CO2, CH4, temperature, humidity; the sensor and its substation, staff location monitoring substation and dispatcher telephone should use matching equipment of existing system; the air vent holes of rescue capsule and the pipelines connecting with compressed air self rescue, supply water rescue, safety monitoring, staff location monitoring and communication system should be placed on both sides of lane. The soft rescue capsule should not be applied to the coal mine; lanes and workplaces should have no less than 2 safety walk paths to surface safely, excepting heading faces and temporary workplaces. Source


Xu D.-J.,China University of Mining and Technology
Meitan Xuebao/Journal of the China Coal Society | Year: 2011

The fracture networks of rock masses in the fault zone were statistically analyzed, which was limited quantity and measured. Statistical models of stochastic probability were built, that was dip of fracture, dip angle, trace length, gap length, and space length. On this basis, the fracture network system of rock masses was simulated by the Monte Carlo method. After that fracture network model was obtained to obey the distribution rules of Gaussian and negative exponential. The calculating results of the example reflect that fracture networks of rock masses in the fault zone are highly permeable, more than 80% structural surfaces are mutual connected and three permeable directions are dominant, that is NE, NW, approximately EW. Source


Song Y.,North China University of Technology | Yang X.,China University of Mining and Technology
Yanshilixue Yu Gongcheng Xuebao/Chinese Journal of Rock Mechanics and Engineering | Year: 2013

The evolution characteristics of deformation fields and temperature fields are inspected and analyzed by using the digital speckle correlation method and infrared thermal imager. The test material is a kind of coal and the specimens are loaded by uniaxial test machine. The analytical results show that: (1) The deformation field evolution of coal specimen is divided into two phases: initial uniform deformation evolution to deformation localization at pre-peak loading stage, and deformation concentration in the localization band at post-peak loading stage. (2) The temperature evolution of coal specimen is divided into two phases: temperature rises due to internal particle spacing change caused by thermo-mechanical coupling effect at pre-peak loading stage; temperature decreases due to the tensile-shear effect and the sliding effect of deformation localization band at post-peak loading stage. (3) The temperature change is obvious in the deformation and destruction process of coal specimens; and the temperature evolution characteristics are similar inside and outside the deformation concentration band. The temperature increases at pre-peak loading stage and decreases at post-peak loading stage. The temperature inside the deformation localization band is higher than that outside the deformation localization band. Source


Hou H.H.,China University of Mining and Technology
Advanced Materials Research | Year: 2014

Researchers have been exploring and innovative for more than fifty years from the birth of gas geology. Gas geology as a subject of preventing, controlling and using coal mine gas has its own practical significance. According to published literature, this paper summarizes the current research situation of gas geology in recent years, and some perspectives of the developmental trend of this subject are carried out through the present the main research contents. © (2014) Trans Tech Publications, Switzerland. Source


Deng Y.-B.,Zhejiang University | Xie K.-H.,Zhejiang University | Lu M.-M.,China University of Mining and Technology | Tao H.-B.,Zhejiang University | Liu G.-B.,Ningbo University
Geotextiles and Geomembranes | Year: 2013

The rate of consolidation by prefabricated vertical drains (PVDs) is closely related to the well resistance, which mainly depends on the discharge capacity of PVDs. According to the existing laboratory tests and field investigations, the discharge capacity of PVDs will decrease with the development of consolidation due to its deformation and siltation and so on. Based on this consideration, in this paper, the discharge capacity was assumed decreased exponentially with time, which resulted in an increase of the well resistance with time during consolidation. Then, a closed-form solution considering the time dependent well resistance for a vertical drain system was developed based on the equal strain condition. Comparisons were presented with some existing solutions for the excess pore water pressure and for the radial average degree of consolidation. The influences of the time dependent well resistance on consolidation rate were then analyzed and the application of the present solution was discussed. © 2012. Source


Sun J.-P.,China University of Mining and Technology
Meitan Xuebao/Journal of the China Coal Society | Year: 2011

The reasons for the 11·5 gas explosion disaster happened in Jiaojiazhai Coal Mine were analyzed in which 47 miners was killed. Firstly, due to the unreliability of the power system, the unexpected power failure happens quite often, and it leads to the ventilator stopping work and the gas density reaching the level which may cause the explosion; secondly, in the state of the gas-electricity being unlocking and without exhausting the accumulated gas first, recovering the power system and ventilation system all of sudden; thirdly, the electric spark produced in an explosion happened in the two-way terminal box of the power cable ignites the gas. The measures for preventing the similar accidents were also studied. They are: to accelerate the research and application of the internet of things in the coal mine; to strengthen the monitoring of the products permitted by the mine-use safety labels, it includes the production, transportation, storage, employment and maintenance of the products, etc.; with the support of the internet of things, to realize multi-level gas monitoring, the gas, power and ventilation locking in the coal mine; to realize multi-level monitoring of the power system and the ventilation system to ensure the finding of the hidden dangers in time and the reliability of the two systems. Source


Sun J.-P.,China University of Mining and Technology
Meitan Xuebao/Journal of the China Coal Society | Year: 2011

The death rate per million tons in leading coal producing countries were compared and analyzed. In 2008, the death rate per million tons in China underground mine was 13.5 times of the USA, 7.9 times of the South Africa, 2. 1times of the Russia, 0.97 times of the India. Through analysis, the reasons that million tons death rate in China was higher than other leading coal producing countries are due to: up to 95% of underground mining, poor storage conditions, severe disaster, lots of small coal mines, low degree of mechanization and informationize, etc. The characteristics of coal mine internet of things are proposed as follows: electric explosion protection, large wireless transmission attenuation, no GPS signal in underground mine, low wireless transmission power, strong anti-interference and anti-fault capability, suitable for using tree-structure, long transmission distance, repeater is inappropriate to be used, small bulk of equipment, powerful adaptive capacity of network voltage fluctuation, be good at protection performance, etc. Put forward the key issues that need to be handled in coal mine internet of things: firstly, the standards of information coding, transmission, processing, etc; secondly, the mine-used safety admittance products in whole control process, which involve production, transportation, storage, application and maintenance; thirdly, whole process manage and safe explosive control in production, transportation, storage, draw and return, usage, etc; fourthly, management and control of main equipments in whole course, production, transportation, storage, application and maintenance are included; fifthly, staff precise location, automatic identification and training, supervision; sixthly, coal gas examiner, safe inspector, fitter, blasting technician, winch man, shearer driver, water pump operator and their operation devices, man-environment lock control; seventhly, ground remote control of unmanned working face; eighthly, management and control of coal at production, transportation, sales, usage; ninthly, management of emergency rescue equipment, ambulance corps, etc; tenthly, coal geological exploration, design, coal mine construction, safety production, management and administration. Source


Liu C.-G.,China University of Mining and Technology | Liu C.-G.,China Resources Coal Holdings Co.
Meitan Xuebao/Journal of the China Coal Society | Year: 2011

In allusion to reveal movement law of overlying strata from mining shallow seam under"two hard"condition, took Majiliang Coal Mine as simuliton entity. The results show that "Domino" effect causes roof failure due to weighting over great extent in pillar mining shallow seam in mining face under "two hard" condition through the simulation experiment, that is to say, overlying strata caving in large area is from direct roof to loose layer. The maximum value of ground subsidence is in the middle of subsidence area, movement of overlying strata is mostly vertical displacement and integral sank inverted ladder. Source


Sun J.-P.,China University of Mining and Technology
Meitan Xuebao/Journal of the China Coal Society | Year: 2011

Coal mine accidents in recent years were analyzed, and the conclusion is that numbers of particular major accident: major accidents: large accident: ordinary accident is 1:5:30:405. Safe production conceptions such as "no death do not mean safety, only safety can guarantee lives, " "simpleness is reliable, margin ensure stabilization", "nobody is safety", "it is easy to coal mining, but hard to assure safe", "balance production" were put forward. Pointed out that important guarantee for safe production are correct concept, logical plan, reliable equipment, practical technology, qualified worker, scientific standard, strict system, refined management, effective rescue and so on, and that safe production are supposed to obtain with normative behaviors and reliable equipments, reaching the goal of environment protection, available disposition, robust institution, perfect system. Source


Yang H.-Y.,East China Institute of Technology | Yue J.-H.,China University of Mining and Technology
Zhongguo Kuangye Daxue Xuebao/Journal of China University of Mining and Technology | Year: 2013

All-time apparent resistivity calculation method is an important component in theoretical system of underground transient electromagnetic method (TEM). Based on analysis of full-space kernel function, kernel function algorithm (KFA) was put forward to calculate full-space all-time apparent resistivity in this paper, and its calculating effect was verified using theoretical data. Meanwhile, its application effect was compared with translation algorithm, which was used to solve all-time apparent resistivity in half-space TEM. The results indicate that, full-space kernel function is a monotonically increasing function of electric conductivity when sampling instant is later than 10 μs and side length of transmitting loop is longer than 5 m. The equivalent side length and the sampling instant of multi-turn coils used in mine all meet this requirement. All-time apparent resistivity obtained from KFA reaches model's "real" resistivity whether it is in early time, in transition region, or in later time. RMS errors of KFA and Translation algorithm are 6.945 1×10-4 and 1.030 0×10-2 with a 10 Ω·m homogeneous full-space model, which indicates that KFA has a higher accuracy and stability. The interpretation of measured data shows that, KFA can achieve a better application effect, which enriches the theoretical system of full-space TEM and provides a reference for measured data processing in mine. Source


Lu W.,China University of Mining and Technology
Applied Optics | Year: 2016

Tunable broadband optical field enhancements are demonstrated for graphene-based nanoscale slot waveguides, and the extremely strong field intensity inside the slot region is produced based on the ultrahigh effective mode index. Analytic formulas are obtained to reveal the dependence of enhanced optical fields and effective mode index on the gap distance, the Fermi energy, the width of nanoribbons, and the background medium. We show that most of the optical field is concentrated within the slot regions with the normalized power about up to 86%, and the averaged optical field intensity reaches 104 μm-2 for the slot waveguide with a 3 nm gap distance and 50 nm width. Meanwhile, the optical field enhancement effect is broadband at infrared frequencies and controlled by Fermi energy via bias electrical voltage for graphene. © 2016 Optical Society of America. Source


Deng J.,Tsinghua University | Wen X.,Tsinghua University | Wang Q.,China University of Mining and Technology
Materials Research Bulletin | Year: 2012

Fe 3O 4-multi-walled carbon nanotubes (Fe 3O 4-MWCNTs) hybrid materials were synthesized by a solvothermal process using acid treated MWCNTs and iron acetylacetonate in a mixed solution of ethylene glycol and ultrapure water. The materials were characterized using X-ray powder diffraction, scanning and transmission electron microscopy, X-ray photoelectron spectroscopy, and vibrating sample magnetometry. The results showed that a small amount of water in the synthesis system played a role in controlling crystal phase formation, size of Fe 3O 4, and the homogeneous distribution of the Fe 3O 4 nanoparticles deposited on the MWCNTs. The Fe 3O 4 nanoparticles had diameters in the range of 4.2-10.0 nm. They displayed good superparamagnetism at room temperature and their magnetization was influenced by the reaction conditions. They were used as a Fenton-like catalyst to decompose Acid Orange II and displayed a higher activity than nanometer-size Fe 3O 4. © 2012 Elsevier Ltd. All rights reserved. Source


Wang H.W.,Tianjin University of Commerce | Zhou H.W.,China University of Mining and Technology | Ji H.W.,Tianjin University of Commerce | Zhang X.C.,Tianjin University of Commerce
Materials and Design | Year: 2014

Damage initiation and propagation in unidirectional glass fiber reinforced epoxy matrix composites under tension load were simulated in this study. Cell models with both single fiber and multi-fiber were modeled by extended finite element method (XFEM) in ABAQUS environment. The damage progresses in the cells were investigated and then the nominal stress-strain curves as well as stress distributions in the fiber and matrix were obtained. Results indicate that the XFEM is an effective modeling technique to study the initiation and propagation of a crack along an arbitrary, mesh-independent, solution-dependent path. In addition, convergence difficulties are familiar issues while carrying out damage and fracture analysis when employing numerical simulation. Several methods, which are helpful to resolve these convergence problems, were presented. Baseline simulations about damage initiation and propagation in composites indicate that a larger value of viscous regularization causes the peak of the reaction force to be higher. A smaller viscosity parameter is better than bigger one. Other advanced techniques, include using automatic stabilization and customized general solution controls, are also adoptable to improve convergence in ABAQUS/Standard analysis. © 2013 . Source


Xia W.,China University of Mining and Technology
Energy Sources, Part A: Recovery, Utilization and Environmental Effects | Year: 2016

ABSTRACT: Biodiesel is a renewable and clean energy which is being developed day by day. However, oil and coal reserves are decreasing due to an increase in energy demand for the development of social economy. Additionally, fine coal is usually beneficiated by flotation using diesel or kerosene as collectors, which may be a waste of energy. Therefore, using biodiesel as a collector for coal flotation has its potential value. In this investigation, biodiesel was used as a collector for coal flotation. Three bituminous coal samples with different coal ranks were selected, that is, gas coal, coking coal, and lean coal. FTIR results showed that biodiesel contained much more abundant unsaturated fatty acids than diesel. Flotation results showed that the flotation performances of three coal samples using biodiesel as collector were similar to that using diesel as collector. Even better, the concentrate yields of three coal samples using biodiesel as collector were a little higher than that using diesel as collector, while their concentrate ash contents were similar. Throughout this paper, it was proved that biodiesel could have a potential application in coal flotation. © 2016 Taylor & Francis Group, LLC. Source


Guo S.-D.,China University of Mining and Technology
Materials Research Express | Year: 2014

We investigate the electronic structures of X Sb 3 (X = Li, K, Cs) by using Tran and Blahas modified Becke and Johnson exchange potential. Calculated energy gaps are substantially better than previous first-principles results with respect to experimental values. The substantial improvement is achieved because the conduction bands are correctly calculated with the new exchange potential. The approach should be applicable to other similar materials. The elastic properties of X Sb 3 (X = Li, K, Cs) are also studied in detail with the generalized gradient approximation such as bulk modulus, shear modulus, Youngs modulus, Poisson s ratio, sound velocities, and Debye temperature. © 2014 IOP Publishing Ltd. Source


Chen S.-H.,Taiyuan University of Technology | Hu Z.-Q.,China University of Mining and Technology
Meitan Xuebao/Journal of the China Coal Society | Year: 2014

Treatment of coal gangue piles with spontaneous combustion has a heavy demand to inert materials. To reach the aims: saving soil, utilization of waste and ensuring environmental benefits, the study on the optimum volume ratio of fly ash to replace partial soil as covering materials for coal gangue piles with spontaneous combustion is purposeful. Fly ash was mixed evenly with silt, silt clay according to different volume ratio. Through the indoor simulation experiment, air isolation effectiveness of different ratio mixed materials of soil and fly-ash was tested, and the influence of fly-ash with different volume to the air barrier property of hybrid materials was analyzed. The results show that, when mixed fly-ash in silt-clay and silt, the air barrier property of mixed materials decreases steadily with the increasing of fly-ash, and approximate expressions respectively shows as an exponential function between permeability and fly-ash content at various pressure differentials. Ash content of 50% and 30%, respectively, determines the isolation changes, which is an important characteristics. It suggests that fly ash content is less than 50% and 30% respectively in silty-soil and in silt-clay. Source


Liu X.,China University of Mining and Technology
Zeitschrift fur Angewandte Mathematik und Physik | Year: 2016

In this paper, we first prove that the solution map of the Cauchy problem for a coupled Camassa–Holm system is not uniformly continuous in (Formula presented.) , the proof of which is based on well posedness estimates and the method of approximate solutions. Then we study the continuity properties of its solution map further and show that it is Hölder continuous in the (Formula presented.) topology with (Formula presented.). Our results can also be carried out on the nonperiodic case. © 2016, Springer International Publishing. Source


Liu J.,China University of Mining and Technology | Pham T.D.,University of New South Wales
Pattern Recognition | Year: 2012

We present in this paper a fuzzy clustering algorithm which can handle spatially constraint problems often encountered in pattern recognition. The proposed method is based on the notions of hyperplanes, the fuzzy c-means, and spatial constraints. By adding a spatial regularizer into the fuzzy hyperplane-based objective function, the proposed method can take into account additionally important information of inherently spatial data. Experimental results have demonstrated that the proposed algorithm achieves superior results to some other popular fuzzy clustering models, and has potential for cluster analysis in spatial domain. © 2011 Elsevier Ltd All rights reserved. Source


Zhu S.,China University of Mining and Technology | Shen Y.,Huazhong University of Science and Technology
Neural Computing and Applications | Year: 2013

This paper presents two algebraic criteria for the input-to-state stability of recurrent neural networks with time-varying delays. The criteria which also ensure global exponential stability when the input u(t) is equal to 0 and is easy to be verified only with the connection weights of the recurrent neural networks. Two numerical examples are given to demonstrate the effectiveness of the proposed criteria. © 2012 Springer-Verlag London Limited. Source


Li D.,China University of Mining and Technology
Journal of Convergence Information Technology | Year: 2011

With the application of the Rytov method proposed by Tatarskii, the light intensity scintillation probability distribution equation of marine atmospheric turbulence is established. Using the signal detection theory, the relationship between light intensity fluctuation and BER resulting from the marine atmospheric turbulence is deduced. The result shows that Cn 2 has obvious diurnal variation, it will reach to the extremum in the afternoon and will show a downward trend with the height increases in the coastal area with its minimum around sunrise period. With the increase of Cn 2, and the decrease of transmission range, when Cn 2 =3×10-15m-2/3, the effective transmission range is 2900m, and allows a 95s adjustment time to APT(acquisition, pointing and tracking)system; The system adjustment time will increase as the Cn 2value decreases and the wavelength increases. Source


Guo P.-Y.,China University of Mining and Technology | Zhu Y.-Y.,Beijing Millennium Engineering Software Co.
Caikuang yu Anquan Gongcheng Xuebao/Journal of Mining and Safety Engineering | Year: 2011

Hot disaster of high temperature is a major obstacle restricting the deep coal mining, so the artificial refrigeration cooling technology is more and more applied in coal mines. How to more accurately calculate the cooling load-an important parameter of the high temperature of artificial refrigeration cooling project will directly affect the cooling project. Based on the existing method of calculating the deep cooling load for multiple parameter uncertainty, we propose a back-analysis algorithm. Under the working face and tunnel airflow temperature, humidity, and other parameters of the measured thermal environment, we calculate the cooling load of working face using the thermodynamics, enthalpy difference. The result has been verified to be correct in Jiahe coal mine. Source


Liang Z.,China University of Mining and Technology
Mathematical Problems in Engineering | Year: 2016

Feature scaling has attracted considerable attention during the past several decades because of its important role in feature selection. In this paper, a novel algorithm for learning scaling factors of features is proposed. It first assigns a nonnegative scaling factor to each feature of data and then adopts a generalized performance measure to learn the optimal scaling factors. It is of interest to note that the proposed model can be transformed into a convex optimization problem: second-order cone programming (SOCP). Thus the scaling factors of features in our method are globally optimal in some sense. Several experiments on simulated data, UCI data sets, and the gene data set are conducted to demonstrate that the proposed method is more effective than previous methods. © 2016 Zhizheng Liang. Source


Shen X.,Nanjing Southeast University | Shen X.,China University of Mining and Technology | Cui T.J.,Nanjing Southeast University | Zhao J.,Nanjing University | And 3 more authors.
Optics Express | Year: 2011

We report the design, fabrication, and measurement of a microwave triple-band absorber. The compact single unit cell consists of three nested electric closed-ring resonators and a metallic ground plane separated by a dielectric layer. Simulation and experimental results show that the absorber has three distinctive absorption peaks at frequencies 4.06GHz, 6.73GHz, and 9.22GHz with the absorption rates of 0.99, 0.93, and 0.95, respectively. The absorber is valid to a wide range of incident angles for both transverse electric (TE) and transverse magnetic (TM) polarizations. The triple-band absorber is a promising candidate as absorbing elements in scientific and technical applications because of its multiband absorption, polarization insensitivity, and wide-angle response. © 2011 Optical Society of America. Source


Kong X.,Tsinghua University | Shi Z.,China University of Mining and Technology | Lu Z.,Tsinghua University
Construction and Building Materials | Year: 2014

Polymer nano-particles (PNPs) with particle size range of 29.4-52.7 nm were synthesized via emulsion polymerization. The mini-cone tests were conducted to evaluate the dispersion capability of PNPs in fresh cement pastes (fcps). Interactions of PNPs with cement were studied by measurements of total organic carbon, zeta potential, transmission electron microscopy, calorimetry and mercury intrusion porosimetry. Results show that the prepared PNPs can be adsorbed on to cement surface and improve fluidity of fcps effectively. The addition of PNPs leads to lesser retardation effect on cement hydration than popularly used polycarboxylate superplasticizers and reduces pore connectivity of micro-pores in hardened cement pastes. © 2014 Elsevier Ltd. All rights reserved. Source


Wang K.,Beijing Institute of Technology | Lu B.,China University of Mining and Technology | Wei Y.-M.,Beijing Institute of Technology
Applied Energy | Year: 2013

Energy and environmental efficiency evaluation has recently attracted increasing interest in China. In this study, we utilize the Range-Adjusted Measure (RAM) based nonparametric approach to evaluate the regional energy and environmental efficiency of China over the period of 2006-2010. The desirable/good and undesirable/bad outputs, as well as the energy and non-energy inputs are considered in the efficiency evaluation so as to characterize the energy consumption, economic production, and CO2 emission process of different China's regions. In addition, the economic concepts of natural disposability and managerial disposability are incorporated in the evaluation instead of the strong and weak disposability in conventional environmental efficiency evaluation. Therefore, the types of returns to scale and damages to scale of different China's regions are measured and correspondingly the strategy and policy implications are proposed for guiding the future improvement of regional energy and environmental efficiency. This study finds that: (i) Beijing, Shanghai, and Guangdong had the highest integrated energy and environmental efficiency during the study period, which could be seen as the benchmarks of inefficient China's regions. (ii) On average, east China had the highest integrated efficiency under natural disposability, and west China had the highest integrated efficiency under managerial disposability. (iii) During 2006-2010, the average production efficiency of China slightly decreased and the average emission efficiency of China slightly increased. (iv) Among China's 30 regions, 19 regions exhibited decreasing returns to scale, 4 regions shown increasing returns to scale, and 7 regions have mixed returns to scale types under natural disposability in our study period. In addition, under managerial disposability, there are 18, 3 and 9 regions respectively exhibited increasing, decreasing and mixed damages to scale types over time. (v) For most Chinese regions, it is not recommended to simply increase or maintain their current scales of production, but alternatively, they should pay more attentions on technology innovation of energy utilization efficiency improvement, since up to 2010, China still had large energy conservation and emission reduction potentials. © 2013 Elsevier Ltd. Source


Chen Y.,Tsinghua University | Huang Z.-H.,Tsinghua University | Yue M.,China University of Mining and Technology | Kang F.,Tsinghua University
Nanoscale | Year: 2014

Organic nanostructures in terms of porphyrin building blocks have shown great potential in visible-light photocatalytic applications because of their optical, electrical, and catalytic properties. Graphenes are known to provide a high-quality two-dimensional (2D) support for inorganic semiconductor nanostructures to increase the adsorption capability of the photocatalysts and an electron-transfer medium with attractive potential to enhance photogenerated charge separation. A combination of porphyrin nanostructures with graphene sheets, particularly in the form of free-standing films, is highly desirable due to its photocatalysing feasibility and convenience. Toward this aim, we demonstrate a facile method to integrate porphyrin (meso-tetra(p-hydroxyphenyl) porphyrin, p-THPP) nanoparticles (NPs) into macroscopic graphene (reduced graphene oxide, rGO) films through vacuum filtration of the co-colloids of graphene oxide (GO) and p-THPP nanoparticles (NPs) followed by gaseous reduction. The obtained p-THPP/rGO nanohybrid film exhibits enhanced visible-light photocatalytic activity compared to each moiety of the hybrid, and this photocatalyst can be easily separated and recycled for successive use with excellent stability. The results show that this facile fabrication of the p-THPP/rGO nanohybrid film makes it available for high-performance optoelectronic applications, as well as for device integration. © 2013 The Royal Society of Chemistry. Source


Ma F.,Shandong Institute of Light Industry | Ma F.,China University of Mining and Technology
Mining Science and Technology | Year: 2010

Coal mining monitoring system has been enforcing tests for the immunity of Electromagnetic Compatibility (EMC) since 2006. However, not all monitoring substations can pass the Electrical Fast Transient/Burst (EFT/B) immunity test and the explosion-proof test simultaneously. In order to enhance EMC, the EFT/B interfere transmission model was presented at the substation power port, after the EFT/B test method was used to analyze the monitoring substation power ports. Hence, a low-pass filter was designed by using the simulation software PIPICE and an anti-jamming method was proposed by way of a parallel connection of the discharge interfere circuit and the low-pass filter. The improved complex EMI filter was made up of an interference discharge device and a filter. The dynamic equivalent circuit was proposed for the EFT/B immunity test. As a result, the monitoring substation has passed the EFT/B immunity and explosion-proof tests with the complex filter. It is concluded that the complex EMI filter has significantly enhanced the immunity of the coal mining monitoring system. © 2010 China University of Mining and Technology. Source


Yang S.,China University of Mining and Technology | Yang S.,Hohai University | Jiang Y.,Hohai University
Mining Science and Technology | Year: 2010

Based on laboratory results of time-dependent mechanical behavior tests, we investigated short-term and mechanical creep behavior of sandstone, observed in conventional triaxial compression experiments at room temperature, using a servo-controlled rheology testing machine. Given our short-term experimental test results, we confirmed deviatoric creep stress levels of sandstone. Multiple deviatoric stress levels were applied in steps to each sample. Each deviatoric stress level before the final failed deviatoric stress was maintained for 48 h or longer. Time-dependent variations of axial strains of sandstone samples are discussed and evaluated. During the creep tests, complete tertiary creep curves of sandstone were observed under failed deviatoric stress levels with different confining pressures. Slices of coal in sandstone samples can lead to distinct tertiary creep deformation failure. © 2010 China University of Mining and Technology. Source


Lu J.,Xuzhou Normal University | Wu D.-M.,Xuzhou Normal University | Wu D.-M.,China University of Mining and Technology | Zheng Y.-L.,Xuzhou Normal University | And 2 more authors.
Brain Pathology | Year: 2010

Purple sweet potato color (PSPC), a class of naturally occurring anthocyanins, protects brain function against oxidative stress induced by D-galactose (D-gal) (Sigma-Aldrich, St. Louis, MO, USA). Our data showed that PSPC enhanced open-field activity, decreased step-through latency, and improved spatial learning and memory ability in D-gal-treated old mice by decreasing advanced glycation end-products' (AGEs) formation and the AGE receptor (RAGE) expression, and by elevating Cu,Zn-superoxide dismutase (Cu,Zn-SOD) (Sigma-Aldrich) and catalase (CAT) expression and activity. Cleavage of caspase-3 and increased terminal deoxynucleotidyl transferase (TdT)-mediated deoxyuridine triphosphate (dUTP) nick-end-labeling (TUNEL)-positive cells in D-gal-treated old mice were inhibited by PSPC, which might be attributed to its antioxidant property. PSPC also suppressed the activation of c-Jun NH 2-terminal kinase (JNK) and the release of cytochrome c from mitochondria that counteracted the onset of neuronal apoptosis in D-gal-treated old mice. Furthermore, it was demonstrated that phosphoinositide 3-kinase (PI3K) activation was required for PSPC to promote the neuronal survival accompanied with phosphorylation and activation of Akt and p44/42 mitogen-activated protein kinase (MAPK) by using PI3K inhibitor LY294002 (Cell Signaling Technology, Inc., Beverly, MA, USA), implicating a neuronal survival mechanism. The present results suggest that neuronal survival promoted by PSPC may be a potentially effective method to enhance resistance of neurons to age-related disease. © 2009 International Society of Neuropathology. Source


Qian M.-G.,China University of Mining and Technology
Meitan Xuebao/Journal of the China Coal Society | Year: 2010

Aiming the position of coal in China's energy, and the effect of huge production capacity and industry negative externality on environment and safety, the connotation of sustainable mining and the requirements in management, technological and economic to achieve sustainable mining were fully expounded, and put forward the conditions of achieving scientific production. For the purpose of sustainable mining, complete cost of coal is necessarily required. Source


Li X.-C.,China University of Mining and Technology
Journal of Coal Science and Engineering | Year: 2010

In recent years, the coal safety has been become the urgent problem in China, and severe and fatal coal mine accidents occurred frequently. Must pay attention to coal safety management immediately, because the coal mine accidents not only caused serious economic losses to the country and people but also had negative impact on the society and politics. A closed loop management system was put forward to build to improve the coal safety management. The closed loop management system was formed four parts, identifying the hazard sources, classifying the hidden troubles hazard sources, the risk prealarm and risk control, and the evaluation system. © The Editorial Office of Journal of Coal Science and Engineering (China) and Springer-Verlag Berlin Heidelberg 2010. Source


Liu J.-C.,China University of Mining and Technology
Nondestructive Testing and Evaluation | Year: 2015

In this paper, we consider the recovery of photon diffusion coefficient in the case of piecewise constant coefficients in optical tomography from boundary measurements of light propagation within a tissue. We propose an effective reconstruction algorithm to detect the number, the location, the size and the shape of piecewise constant coefficients. This problem is nonlinear and severely ill-posed, thus we should consider a regularisation technique in our approach in order to improve the corresponding approximation. We give several examples to show the viability of our proposed method. © 2015 Taylor & Francis. Source


Ma L.-Q.,China University of Mining and Technology | Li Y.-S.,Zaozhuang Mining Group Co.
Meitan Xuebao/Journal of the China Coal Society | Year: 2010

Based on the analysis of the source of coal mine underground gangue, established the coal with gangue underground separation system, mainly including screening, sorting and return to coal in process, and increased the fully mechanized top coal caving recovery, and solved the jamming problem in hoisting and transportation system, and improved cotrol flow of underground coal quality. In the implementation of the pressure tunnel filled with gangue under the surface construction, water body, railway unexploited coal zone, and gangue-based materials developed by the "pre-structure man-made wall, gangue replacement of narrow coal pillar" roadway driven along the goaf technology, formed a set of replacement of coal with gangue cleaner production technologies. Source


Miao X.-X.,China University of Mining and Technology
Zhongguo Kuangye Daxue Xuebao/Journal of China University of Mining and Technology | Year: 2010

The coal mining technology of fully-mechanized solid filling (or waste filling) can be used to recover the resource of three underground coal and the coal pillar, which can enhance the coefficient of coal recovery, circularly utilize the solid waste in mining area and protect the land resource, water resource and the environment. On the basis of briefly describing the coal mining method of fully-mechanized solid filling and its effects on the strata controlling, the remarkable differences in the principles of underground pressure control and mining supporter design between this method and ordinary longwall mechanized mining method are compared. The underground pressure model with equivalent mining height of solid filling which is used to analyze the law of strata moving and surface subsidence is improved. Based on the proposed supporter design of mechanized mining with solid filling, the mechanic model of underground pressure that is used to analyze the roof deformation induced by the initiative loading of supporter is established. According to the Flamant's solution of a concentrated force act on infinite half plane, the analytical solution that can calculate the displacement curve of roof deformation induced by the active force provided by the supporter is obtained. This research work has important impelling action on improving the basic theory of coal mining with solid filling. Source


Sun J.-P.,China University of Mining and Technology
Meitan Xuebao/Journal of the China Coal Society | Year: 2010

Analyzed the causes of "2·22" gas explosion disaster at Tunlan Coal Mine which led the death of 78 people. It was the breezeless condition of No.1 crossheading at 12403 working face in the coal mine's southern No.4 panel region that made the local gas accumulated to the explosive concentration. It was the electrical switch which lost its explosion-proof ability in No.1 crossheading that ignited the gas. Some conceptions were put forward as following, none of people is safe, simplicity means reliable, large redundancy ensures safety, no death is not equal to safety, only safety guarantees no death, etc. Meanwhile, some propositions were discussed, as coal mines should improve their mechanization, informationization and automation to reduce the numbers of underground miners, to simplify the ventilation and power supply systems, to set the electrical equipments in the places with total pressure fresh airflow, to reduce the application of local fans as much as possible, to properly increase the redundancy of the systems and equipments for ventilation, power supply, hoisting and transportation, to reduce the middle links of the coal mine's safety supervision systems, and to adopt isolated self-rescuers in high gas concentration and coal and gas outburst mines, etc. Source


Han F.,China University of Mining and Technology
International Journal of Earth Sciences and Engineering | Year: 2014

Based on the previous and current known information and data of ventilation system, mine ventilation network simulation and prediction is a new algorithm that reproduces the operating features of ventilation system previously, discovers and masters its status during operating period and predicts the future trends of the system by using scientific method. Using complex network theory, this paper proposes to intermittently use the random walk in the maximum search. It ensures the superiority of the two algorithms and extends the range of the available network algorithm. In addition, searching with the k walker improves the search speed and is applicable to various types of complex networks. Simulation results show the advantages of the algorithm. © 2014 CAFET-INNOVA TECHNICAL SOCIETY. All rights reserved. Source


Wu Q.,China University of Mining and Technology
Meitan Xuebao/Journal of the China Coal Society | Year: 2014

Based on the comprehensive summary of the theory and method, application technology, practical engineering and technical standard of prevention and control technology of mine water disaster as well as its reutilization in China at present, this paper systematically analyzed the latest research progress and achievements of basic theory, hydrogeology (supplement) exploration, advanced detection and monitoring as well as early warning in order to further promote application of current technologies and develop new technologies and methods. And pointed out the challenges and the existing problems of the field, the gaps with requirements of fast, intensive, large-scale development of the coal industry in China, and discussed the development trends, future important scientific innovation and key technologies. The prospects of the industry and technology were also forecast. Source


He M.-C.,China University of Mining and Technology
Meitan Xuebao/Journal of the China Coal Society | Year: 2014

With the increase of mining depth, deep geological environment, such as the stress increases, water inflow increases, and ground temperature rises, is more complex. The deep engineering disaster becomes increasingly serious, especially the deep soft rock engineering disasters, which bring severe challenges to the research of deep soft rock engineering problems. The author based on the scientific definition of deep discusses the progress of deformation and failure mechanism, test methods and equipments in deep soft rock engineering from the following several aspects: water softening mechanism, asymmetric large deformation mechanism, rock burst mechanism, softening large deformation mechanism caused by hot and humid environment and so on; summarizes the progress of the deep soft rock large deformation design methods, control technology and new constant resistance large deformation material which is based mainly on constant resistance large deformation bolt; and puts forward the major challenges of deep soft rock engineering in the future. Source


Dong J.,China University of Mining and Technology | Huo N.,Tianjin University
Composite Structures | Year: 2016

Pore defects have significant effect on the mechanical properties of 3D braided composites. Two-scale finite element models of the fiber tows and the braided composites are developed to predict the elastic properties and the micro stress of 3D braided composites. Two basic types of pore defects, the voids in resin matrix and the dry patches in fiber tows, have been taken into account. Periodical boundary conditions are applied on the two-scale FE models by the coupling and constraint equation defining commands in ANSYS. The predicted effective elastic constants agree well with the available experimental data, demonstrating the validity of the two-scale FE models. The effects of braiding angle and fiber volume fraction on the engineering elastic constants are discussed. Furthermore, the effects of two types of defects on the effective elastic properties of 3D braided composites are also discussed in detail. Some useful conclusions are drawn herein. From simulation, dry patches in fiber tows have more significant effect on the elastic properties than voids in matrix. © 2016 Elsevier Ltd. Source


Zhao M.,China University of Mining and Technology
Chemistry - An Asian Journal | Year: 2016

Monodisperse palladium phosphide nanoparticles (Pd-P NPs) with a smallest size ever reported of 3.9nm were fabricated using cheap and stable triphenylphosphine as phosphorous source. After the deposition and calcination at 300 °C and 400 °C, the resulting Pd-P NPs increased in size to 4.0nm and 4.8nm, respectively. Notably, the latter NPs probably crystallized with a single phase of Pd3P0.95, which acted as a highly active catalyst in semi-and stereoselective hydrogenation of alkynes. X-ray photoelectron spectroscopy analysis determined a positive shift of binding energy for Pd(3d) in Pd-P NPs compared to that in Pd on carbon. It indicated the electron flow from metal to phosphorus and the larger electron deficiency of Pd in Pd-P NPs, which suppressed palladium hydride formation and subsequently increased the selectivity. Thus, this result may also indicate the applications of Pd-P and other metal-P NPs in various selective hydrogenation reactions. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Source


Zhang Z.Z.,China University of Mining and Technology
Advances in Materials Science and Engineering | Year: 2015

Experiments on granite specimens after different high temperature under uniaxial compression were conducted and the fracture surfaces were observed by scanning electron microscope (SEM). The fractal dimensions of the fracture surfaces with increasing temperature were calculated, respectively. The fractal dimension of fracture surface is between 1.44 and 1.63. Its value approximately goes up exponentially with the increase of temperature. There is a quadratic polynomial relationship between the rockburst tendency and fractal dimension of fracture surface; namely, a fractal dimension threshold can be obtained. Below the threshold value, a positive correlativity shows between rockburst tendency and fractal dimension; when the fractal dimension is greater than the threshold value, it shows an inverse correlativity. © 2015 Z. Z. Zhang. Source


Song Y.-M.,North China University of Technology | Yang X.-B.,China University of Mining and Technology
Caikuang yu Anquan Gongcheng Xuebao/Journal of Mining and Safety Engineering | Year: 2013

In this paper, based on the uniaxial compression test of coal samples, the evolution characteristics of deformation and energy fields during coal pillar instability process were studied. Meanwhile, the specimen surface speckles images were recorded by CCD camera. Combined with the monitoring results of coal samples' whole deformation and failure process by using the digital speckle correlation method, the generation and evolution of deformation localization in coal pillar, as well as the characteristics of coal pillar instability in each stage were systematically analyzed. Then, the energy evolution during coal pillar instability process was calculated. The results show that the coal pillar instability can be divided into two types: unstable propagation of fracture inner coal piller and unstable sliding of weak plane inner coal piller. The energy release and accumulation patterns during loading process of coal pillar are mainly controlled by the final instability modes. Comparatively speaking, the energy release rate during the weak plane unstable sliding inner coal piller is relatively small, while the energy release rate during the fracture unstable propagation is larger. Source


Li M.,China University of Mining and Technology
Journal of Communications | Year: 2015

This paper addresses the problem of the roadway environment and Non-Line of Sight (NLOS) propagation on localization accuracy in coal mine. Unlike prior localization algorithms, reference nodes are deployed according to the actual environment in coal mine, and Time-of-Arrival (TOA) and Receive Signal Strength (RSS) measurements using Ultra- Wideband (UWB) signals are combined to obtain better localization accuracy. A two-step method is proposed to estimate the object location, which uses RSS data first to calculate the range of target position, and TOA data is combined to get the object precise location by data fusion. Then analytical expressions for the probability of detection and the Cramer-Rao Lower Bound (CRLB) for this scheme and TOA method are given for comparison. Detailed simulation experiments are presented to validate the effectiveness of this proposed method. Simulation results demonstrate that the proposed methods perform better than traditional TOA measurements based on UWB signals. © 2015 Journal of Communications. Source


Zhang W.,China University of Mining and Technology
International Journal of Mining Science and Technology | Year: 2014

In order to effectively decrease the safety accidents caused by coal miners' human errors, this paper probes into the causality between human errors and life events, coping, psychological stress, psychological function, physiological function based on life events' vital influence on human errors, establishing causation mechanism model of coal miners' human errors in the perspective of life events by the researching method of structural equation. The research findings show that life events have significantly positive influence on human errors, with a influential effect value of 0.7945 and a influential effect path of "life events - psychological stress - psychological function - physiological function - human errors" and "life events - psychological stress - physiological function - human errors". © 2014 Published by Elsevier B.V. on behalf of China University of Mining and Technology. Source


Li M.,China University of Mining and Technology
Journal of Communications | Year: 2015

An average Transmitted-Reference (TR) receiver scheme based on orthogonal codes is proposed for improving the bit error rate (BER) performance and the transmitting rate of Ultra-wideband (UWB) TR receiver systems in coal mine. Orthogonal codes are used for modulating the reference pulses and the data pulses in each frame of every bit. Since the orthogonality of the two codes, the inter-pulse interference (IPI) is greatly reduced. Then the decoding reference pulses and the data pulses are averaged in a frame, which decreases the noise in the reference pulses and the data pulses. Finally, I demonstrate this optimal receiver scheme by the simulation in the coal mine roadway ultra-wideband channel model. Detailed simulation experiments are presented to validate the effectiveness of this proposed method. The experimental results show that this method can not only efficiently reduce the noise interference in receiving signals, but also can provide higher transmission rate, which make UWB signal receiving in coal mines more accurately. © 2015 Journal of Communications. Source


Qiu L.,China University of Mining and Technology
Chinese Physics Letters | Year: 2011

Dynamics of the nonlocality measured by the violation of Svetlichny's Bell-type inequality is investigated in the non-Markovian model. The phenomenon of nonlocality sudden birth for the atoms and the reservoirs is obtained. The evolution of the nonlocality among the atoms or the reservoirs depends on the choice of the atom detuning from the cavity pseudomode, the cavity pseudomode decay and the rotation angles. For the small pseudomode decay in the near-resonance regime, the initial atomic nonlocality is completely transferred to the reservoirs ultimately. © 2011 Chinese Physical Society and IOP Publishing Ltd. Source


Yang X.-J.,Zhengzhou University | Yang X.-J.,China University of Mining and Technology | Baleanu D.,Cankaya University | Baleanu D.,King Abdulaziz University | Baleanu D.,Romanian Space Science Institute
Thermal Science | Year: 2013

This paper points out a novel local fractional variational iteration method for processing the local fractional heat conduction equation arising in fractal heat transfer. Source


Liu C.-M.,Xuzhou Normal University | Ma J.-Q.,China University of Mining and Technology | Sun Y.-Z.,Xuzhou Normal University
Environmental Toxicology and Pharmacology | Year: 2010

Quercetin, a flavonoid, effectively improved the lead-induced histology changes including structure damage and leukocyte infiltration in rat kidney. The present study was designed to explore the protective mechanism of quercetin against lead-induced oxidative DNA damage and apoptosis in rat kidney. We found that quercetin markedly decreased the ROS level and lowered the GSH/GSSG ratio in the kidney of lead-treated rat. The increase of 8-hydroxydeoxyguanosine level in the kidney of lead-treated rat was effectively suppressed by quercetin. Furthermore, quercetin markedly restored Cu/Zn-SOD, CAT and GPx activities in the kidney of lead-treated rat. TUNEL assay showed that lead-induced apoptosis in rat kidney was significantly inhibited by quercetin, which might be attributed to its antioxidant property. In conclusion, these results suggested that quercetin could protect the rat kidney against lead-induced injury by improving renal function, attenuating histopathologic changes, reducing ROS production, renewing the activities of antioxidant enzymes, decreasing DNA oxidative damage and apoptosis. © 2010 Elsevier B.V. Source


Wang Q.-D.,China University of Mining and Technology
Energy and Fuels | Year: 2013

The development of the combustion mechanism for hydrogen (H2) and C1-C4 hydrocarbon fuels plays critical roles in many combustion systems. In the present work, a general framework to develop an efficient skeletal mechanism, which can maintain both accuracy of predicted combustion properties and chemical reality, has been established on the basis of the combination of the directed relation graph method for mechanism reduction and the element flux analysis method for reaction pathway analysis. Within the framework, a skeletal mechanism with 56 species and 428 reactions is developed from a detailed mechanism, including 111 species and 784 elementary reactions, for high-temperature combustion of H2, and C1-C 4 hydrocarbons. Errors in the predicted combustion properties will be introduced via removing species from detailed mechanisms. Therefore, systematical error analysis is first performed for ignition over a wide range of conditions, including temperature, pressure, and equivalence ratio, to check the robustness of the skeletal mechanism. Results show that the accuracy of the skeletal mechanism in the prediction of ignition for hydrogen, methane, ethylene, ethane, and propene is within 5% and no more than 10% for propane and n-butane. Time-integrated element flux analysis is subsequently used as an efficient method to check the chemical reality of the skeletal mechanism. The results indicate that the skeletal mechanism maintains the major reaction paths for targeted fuels. Finally, the skeletal mechanism is validated via the predictions of ignition, laminar flame speed, species profiles, and diffusion counter-flow flame simulations, and the use of the skeletal mechanism in the development of simplified high-temperature combustion mechanism for large alkanes is also performed. © 2013 American Chemical Society. Source


Meng Z.,China University of Mining and Technology | Meng Z.,China Three Gorges University | Li G.,Hubei University
Engineering Geology | Year: 2013

In order to investigate the permeability behavior of high rank coal during early depletion of CBM and its influencing factors, we collected 14 coal samples from Ordos Basin in northwest China and determined their air permeability under a varying effective stress of 2.5-20. MPa in laboratory. We used effective confining pressure to simulate effective stress. It turns out that high rank coal permeability is susceptible to effective stress. Permeability of coal samples declines exponentially with the rise of effective stress on the whole. When effective confining pressure variation ranges from 2.5. MPa to 10. MPa, permeability varies dramatically; when effective confining pressure rises to above 10. MPa, the curve of permeability decline gets gentle and the stress sensitivity becomes relatively weak. Coal permeability is also affected by coal moisture, maceral, fracturing and metamorphism degree. Permeability rises with the increase of vitrinite content and fracturing degree and decreases with the increase of moisture content. Permeability of wet and fractured coal samples is more sensitive to effective stress than dry intact ones and the irreversible permeability loss rate of fractured coal cores is significant, over 80%. Comparison of tests results of medium and low rank coal samples and high rank ones shows that, the stress sensitivity coefficient decreases with the increase of the maximum reflectance of vitrinite; if experiencing the same load-relief process, the irreversible permeability loss rate of low rank coal is less than that of medium and high rank coals. © 2013 Elsevier B.V. Source


Qiu L.,China University of Mining and Technology
Chinese Physics Letters | Year: 2011

The dynamical evolution of nonclassical correlation in interacting qubits is investigated under the correlated dissipative environments for two classes of initial states. If the correlated decay rate equals the independent decay rate, there will be stationary nonclassical correlation between the qubits prepared initially in some separable states. When the correlated decay rate is different from the independent decay rate, the nonclassical correlation between the qubits eventually decays to zero for a certain class of initial states. © 2011 Chinese Physical Society and IOP Publishing Ltd. Source


Bai L.,China University of Mining and Technology | Zhang Z.-Z.,Nanjing University | Jiang L.,Nanjing University
Physics Letters, Section A: General, Atomic and Solid State Physics | Year: 2011

With the aid of the nonequilibrium Green's function and the Lang-Firsov canonical transformation, we investigate the joint effects of a phononic environment and the spin-flip scattering on the Andreev reflection (AR) in a ferromagnet/single-molecular quantum dot/superconductor (FM/MQD/SC) system. In the presence of the strong electron-phonon interaction (EPI), it is found that the EPI strongly suppresses the AR current (called the Franck-Condon blockade). When the coherent spin-flip (similar to a transverse magnetic field) is taken into account within the MQD, the AR current is significantly enhanced, furthermore, the spin-polarized AR current or even the pure spin-polarized AR current can be generated. By tuning the system parameters, the amplitude and direction of the AR current can be changed, this provides an efficient mechanism for controlling the AR process. © 2010 Elsevier B.V. All rights reserved. Source


Zhao L.-C.,Hefei University of Technology | Zhao L.-C.,CAS Beijing Institute of Applied Physics And Computational Mathematics | He S.-L.,China University of Mining and Technology
Physics Letters, Section A: General, Atomic and Solid State Physics | Year: 2011

We present Lax-pair corresponding to the coupled Gross-Pitaevskii equation (CGPE) which governs the evolution of the macroscopic wave function of two components Bose-Einstein condensates trapped in time-dependent harmonic potential. Kinds of soliton solutions can be derived from the Lax-pair through Darboux transformation conveniently. Furthermore, soliton management in two-component Bose-Einstein condensate would be realized base on that the shape and motion of soliton in both components are investigated analytically. Moreover, it is found that there is a transformation existed between the nonautonomous coupled system and Manakov model. © 2011 Elsevier B.V. All rights reserved. Source


Hong L.,China University of Mining and Technology
Advanced Materials Research | Year: 2014

In DSCM,mean of a seriously polluted target image's subdomain usually has a significant random fluctuation, this reduces the accuracy of subpixel registration. This paper proposed a algorithm to inhibit the fluctuation by replacing the mean of target subdomain with the mean of a superset domain. Experimental data shows that in some places this process can significantly improve the accuracy of correlation measure function's interpolation. © (2014) Trans Tech Publications, Switzerland. Source


Wang Q.-D.,China University of Mining and Technology
Wuli Huaxue Xuebao/ Acta Physico - Chimica Sinica | Year: 2016

Directed relation graph (DRG) based skeletal reduction methods have become the mainstream approach for skeletal mechanism generation because of their simple concept and low computational cost. Within the DRG framework, the definitions of the interaction coefficients and the connection weights in different DRG methods control the resulting skeletal mechanisms. In this work, based on DRG methods, four contemporary definitions of the interaction coefficients in conjunction with both standard DRG and error propagation (EP) graph search methods are used to derive skeletal mechanisms for methyl butanoate (MB) combustion. Detailed comparisons of contemporary DRG based methods are performed by systematic error analysis. To further evaluate the performance of the different DRG-based methods, reaction paths are investigated via element flux analysis to check the chemical kinetics of the resulting skeletal mechanisms. Furthermore, a 96-species skeletal mechanism for MB combustion is proposed. Reaction path analysis highlights the importance of propene chemistry during MB oxidation. This work reveals the applicability of reaction path analysis in skeletal reduction using different DRG-based methods, and also provides critical information for further development of skeletal reduction methods. © Editorial office of Acta Physico-Chimica Sinica. Source


Shi W.,Hong Kong Polytechnic University | Hao M.,China University of Mining and Technology
International Journal of Remote Sensing | Year: 2013

Misregistration between multitemporal remotely sensed images is one of the significant sources of change-detection errors. In this study, spatial distribution of change-detection errors induced by misregistration was analysed quantitatively. First, multitemporal images are registered with different misregistration values measured by root mean square error (RMSE) from 0 to 1 pixels. The image differencing method, one of the most widely used change-detection methods, is then used to detect changes. Finally, the spatial distribution pattern of change-detection errors caused by misregistration is analysed using buffering analysis based on multitemporal image edges. Experimental results indicate that the commission errors caused by misregistration values from 0 to 1 pixels are almost always within 1 pixel of the edge, regardless of image resolution. In addition, the omission errors falling within 1 pixel of the edges are about 70% for medium-resolution images. The omission errors falling within 1 or 2 pixels of the edges for high-resolution images can be as much as 50% to 60%. This work improves the understanding of spatial distribution of change-detection errors caused by misregistration and shows the relations between these errors and image edges. Moreover, it is helpful for developing new methods by combining edge and spatial information to reduce the adverse effects of misregistration on change-detection. © 2013 Copyright Taylor and Francis Group, LLC. Source


Gao M.,University of Science and Technology of China | Gao M.,China University of Mining and Technology | Sun Y.,University of Science and Technology of China
Polymer Engineering and Science | Year: 2013

Bisphenol A bis(diphenyl phosphate) oligomer (BBO) as flame retardant was synthesized, whose structure was characterized by IR and NMR. In all, 20% weight mixture polyphosphoric acid (APP) and BBO was doped into epoxy resins (EPs) to get 26.0% of limiting oxygen index and UL 94 V-0. The degradation behavior of EP-containing BBO/APP was studied by thermogravimetry, differential thermogravimetry, scanning electron microscopy, and cone calorimeter. The activation energies for the decomposition of EP samples are obtained using the method of Kissinger. The experimental results exhibited that for EP-containing BBO/APP, compared with EP, initial decomposition temperature, maximum temperature at the peak position (Tm), and the activation energy for the decomposition are decreased, whereas the maximum weight loss rate (R max), char yields, and the inherent thermal stability are increased. Meanwhile, heat release, smoke production, and CO yield and CO2 yield of EP-containing BBO/APP are much decreased compared with those of EP. The thermal degradation mechanism of EP-containing BBO/APP has been proposed. Copyright © 2013 Society of Plastics Engineers. Source


Liu H.,China University of Mining and Technology
Optical Engineering | Year: 2011

Hai Liu graduated in 2009 from school of Optoelectronic Science and Engineering, Huazhong University of Science and Technology, and became a lecturer of School of Information and Electrical Engineering, China University ofMining and Technology in the same year. His main research interests include integrated optoelectronic, computational electromagnetic, and photonics. The relationship between spatial localization and bichromatic emission phenomena in one-dimensional (1D) active random media with gain is investigated by simultaneously solving Maxwell's equations and rate equations of electronic population. Results indicated that the increase of the concentration of the dye increases the spectral intensity of the dimer and the increase of the pump energy produces major radiative and nonradiative energy transfers from monomers to dimers. The increase of the ratio of the concentration of monomer to that of dimer would reduce the intensity of localization and increase the threshold of lasing mode. The competition between two lasing modes in 1D active random media can be controlled by local pumping. The results agree very well with the experimental data and offer a useful method for mode-selection. © 2011 Society of Photo-Optical Instrumentation Engineers (SPIE). Source


Li H.,Dalian University of Technology | Mu H.,Dalian University of Technology | Zhang M.,China University of Mining and Technology | Gui S.,Dalian University of Technology
Energy | Year: 2012

With the intensification of global warming, the issue of carbon emissions causes more and more attention in recent years. In this paper, China's 30 provincial-level administrative units are divided into five emission regions according to the annual average value of provincial CO 2 emissions per capita during 1990 and 2010. The regional differences in impact factors on CO 2 emissions are discussed using STIRPAT (stochastic impacts by regression on population, affluence, and technology) model. The results indicate that although GDP (Gross domestic product) per capita, industrial structure, population, urbanization and technology level have different impacts on CO 2 emissions in different emission regions, they are almost always the main factors in all emission regions. In most emission regions, urbanization and GDP per capita has a bigger impact on CO 2 emissions than other factors. Improving technology level produces a small reduction in CO 2 emissions in most emission regions, but it is still a primary way for CO 2 reduction in China. It's noteworthy that industrial structure isn't the main factor and improving technology level increases CO 2 emissions in high emission region. Different measures should be adopted for CO 2 reductions according to local conditions in different regions. © 2012 Elsevier Ltd. Source


Yang X.-J.,China University of Mining and Technology | Srivastava H.M.,University of Victoria | Cattani C.,University of Salerno
Romanian Reports in Physics | Year: 2015

In this article, we propose and apply a local fractional homotopy perturbation method, which is and extended form of the classical homotopy perturbation method. We discuss convergence aspect of the technique and present two illustrative examples to show the efficiency of the proposed method in order to find the approximate solutions for some local fractional differential equations arising in mathematical physics. © 2015, Editura Academiei Romane. All rights reserved. Source


Guo J.,China University of Mining and Technology
Applied Mechanics and Materials | Year: 2014

The green coal mines is the only way to change the extensive development mode of the coal mines.After analysis of dynamic formation mechanism of the green coal mine construction,this paper thinks the impetus of the green coal mine construction includes external impetus and internal impetus,where external impetus includes government support,environmental protection pressure,the degree of regional capital market maturity and technology innovation system of coal industry and internal impetus includes the drive of responsibility and interest,the ensuring strength of organization and culture,the enterprises technology innovation system and the sustainable development ability.This paper proposes a dynamic factors interaction model of green coal mine construction and some suggestions to construct green coal mines. © (2014) Trans Tech Publications, Switzerland. Source


Xia J.,China University of Mining and Technology | Xia J.,Grenoble Institute of Technology | Du P.,Nanjing University | He X.,Grenoble Institute of Technology | Chanussot J.,Grenoble Institute of Technology
IEEE Geoscience and Remote Sensing Letters | Year: 2014

In this letter, an ensemble learning approach, Rotation Forest, has been applied to hyperspectral remote sensing image classification for the first time. The framework of Rotation Forest is to project the original data into a new feature space using transformation methods for each base classifier (decision tree), then the base classifier can train in different new spaces for the purpose of encouraging both individual accuracy and diversity within the ensemble simultaneously. Principal component analysis (PCA), maximum noise fraction, independent component analysis, and local Fisher discriminant analysis are introduced as feature transformation algorithms in the original Rotation Forest. The performance of Rotation Forest was evaluated based on several criteria: different data sets, sensitivity to the number of training samples, ensemble size and the number of features in a subset. Experimental results revealed that Rotation Forest, especially with PCA transformation, could produce more accurate results than bagging, AdaBoost, and Random Forest. They indicate that Rotation Forests are promising approaches for generating classifier ensemble of hyperspectral remote sensing. © 2013 IEEE. Source


Miao Z.,Hong Kong Polytechnic University | Miao Z.,China University of Mining and Technology | Shi W.,Hong Kong Polytechnic University
Remote Sensing Letters | Year: 2014

This study presents an automatic method for accurate road centreline extraction from classified images. Unlike earlier methods that have mainly relied on the thinning algorithm, the proposed automatic method selects end points from a classified image and then connects them using the geodesic method to formulate the road network. As the proposed method generates the road centreline by tracing along the ridge line of the optimally oriented flux (OOF) measure, this method is able to eliminate undesired spurs while retaining the correct road network topology. Three test images are used to quantitatively evaluate the proposed method. Experiments show that the proposed method yields a substantial improvement over the thinning algorithm. © 2014 © 2014 Taylor & Francis. Source


He M.,State Key Laboratory for GeoMechanics and Deep Underground Engineering | He M.,China University of Mining and Technology
Engineering Geology | Year: 2011

Physical modeling of excavation of a roadway tunnel in the geologically 45° inclined rock strata by using a newly developed physical modeling approach, the so-called "Physically Finite Elemental Slab Assemblage (PFESA)", together with infrared (IR) thermography, were conducted for visualization and observation of the progressive development of the excavation damaged zone (EDZ). The excavation was schemed as two phases, i.e. phase 1: the full-face excavation and phase 2: the staged excavation. The experiment was performed under unbalanced confinement found in underground coal mining. The relative temperatures of the excavation zone were mapped by the IR camera, in real time and over the entire field, into thermography series which were processed using such procedures as statistics, noise removal and spectral-frequency analysis for image feature extraction. IRT, defined as the statistical mean of the thermography matrix, was used as a measure of rock responses, characterizing the full-face excavation and the staged excavation as a multi-linearity and nonlinearity processes respectively by its time-marching scheme. The temporal and spatial evolutions of the EDZ were described in detail by the denoised thermographies. Directional propagations of the excavation induced stress wave were characterized by the spectral-frequency analysis of the resultant thermographies. © 2010. Source


Liu X.,Xian Jiaotong University | Tian X.,Xian Jiaotong University | Lu T.J.,Xian Jiaotong University | Zhou D.,Xian Jiaotong University | Liang B.,China University of Mining and Technology
Composite Structures | Year: 2012

The dynamic responses and blast resistance of all-metallic sandwich-walled hollow cylinders with graded aluminum foam cores are investigated using finite element simulations, and compared with those of conventional ungraded ones. After validating the numerical approach and introducing the computational model, sandwich-walled hollow cylinders with various graded aluminum foam cores are analyzed under air blast loading. It is demonstrated that the radial deflection of graded cylinders is smaller than and the blast resistance superior to that of ungraded ones when subjected to identical air blast loading. This can be further improved by optimizing the foam core arrangement. Finally, the influence of face-sheet arrangements on the dynamic behavior of graded cylinders is explored. © 2012 Elsevier Ltd. Source


Liu K.,Hong Kong Polytechnic University | Shi W.,Hong Kong Polytechnic University