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Gao Y.,Center for Engineering Design and Research under the Headquarters of General Equipment | Ma L.,Peking University | Liu W.,Center for Engineering Design and Research under the Headquarters of General Equipment | Xu Y.B.,Peking University | Liu Q.,Center for Engineering Design and Research under the Headquarters of General Equipment
Applied Mechanics and Materials | Year: 2013

While crowdsourcing is developed as a business model, it has become a new method of information exchange under the development of mobile Internet and SNS, and promoted the method of information production and exchanging on Internet. During the processes of global huge disaster relief, mass of information released by normal people have been used and played an important role. Using crowdsourcing in disaster information collection can improve the efficiency of rescue. Based on the analysis of current status of disaster information collection and crowdsourcing model, this paper studied the crowdsourcing-compatible disaster information management system, including its' content, architecture and future development direction. © (2013) Trans Tech Publications, Switzerland.


Yang G.-L.,China University of Mining and Technology | Jiang L.-L.,Center for Engineering Design and Research under the Headquarters of General Equipment | Huo C.,China University of Mining and Technology
Proceedings of the 2011 2nd International Conference on Digital Manufacturing and Automation, ICDMA 2011 | Year: 2011

The separate element and common node model is setup to simulate reinforced concrete material at first, which could take fully account of the intensity difference of concrete and rebar. And then a 16-storied frame structure is build with this kind of model. The blasting demoLition process of the structure is simulated. The mechanism of collapse process and failure of column are analyzed. Finally, the scopes of collapse of calculation and practice are compared, and the errors of forwards and backwards distance are +11.9 and -16.6%. The simulation result has great practical significance to determine blasting parameters and optimize design. © 2011 IEEE.


Yang G.-L.,China University of Mining and Technology | Yang R.-S.,China University of Mining and Technology | Jiang L.-L.,Center for Engineering Design and Research under the Headquarters of General Equipment
Baozha Yu Chongji/Explosion and Shock Waves | Year: 2012

Simulations were performed to analyze the propagation and superposition processes of stress waves aiming to three different charge structures under top, bottom and simultaneous initiations, respectively. The pressure in the middle of the borehole increases greatly when increasing the top charge under top and simultaneous initiations. Adopting bottom initiation, the pressure peaks of stemming part are higher than those adopting the other two initiations. For three charge structures under bottom initiation, comparisons of the pressure curves along the boreholes display that more even-distributed pressure can be obtained and the corresponding mean pressure is higher by increasing the top charge. The simulated results were applied to the field practice and the big fragments were deleted basically. So the gangue backfill efficiency can increase by adopting air-deck charge blasting.


Yang G.-L.,China University of Mining and Technology | Jiang L.-L.,Center for Engineering Design and Research Under the Headquarters of General Equipment | Yang R.-S.,China University of Mining and Technology
Zhongguo Kuangye Daxue Xuebao/Journal of China University of Mining and Technology | Year: 2013

With the depth increase of cut blasting holes, the clamping effect of rockmass becomes manifested, leading to poor throw of rock fragments and low utility of blast holes, which directly influences the rate of roadway drivage in rocks. In this study, a duplex wedge cut blasting with 12 holes is studied by numerical method. The simulation results reveal the propagation of stress waves in the hollow cavities and the formation process of cavities at the bottom of the blasting holes, where two stress peaks are formed, which makes the crushing of the rock much effective. The presence of the center hole enhances the throw of the broken rocks, and improves the utilization efficiency of blasting holes. In situ blasting tests were carried out with a blasting hole of 3 m deep. An average utility of 94.9% of the blasting holes was achieved in 10 tests.


Wu X.,Center for Engineering Design and Research under the Headquarters of General Equipment | Wu X.,Naval Institute of Hydrographic Surveying and Charting | Zhang C.,University of Chinese Academy of Sciences | Wang K.,Zhengzhou University
Acta Geodaetica et Cartographica Sinica | Year: 2011

The basic equations for the solution of global point-mass model based on the complex combination and complete tensor components of global gravity gradient were studied and established in this paper, from which point-mass harmonic analysis solutions of single determined and over determined boundary value problems based on satellite gravity gradient were attained. The stability of point-mass harmonic analysis solutions was obtained via the decomposition of large linear equations using blocked cyclic matrices. Finally, simulation experiments with EGM 2008 were made to validate the validity and feasibility of point-mass harmonic analysis of satellite gravity gradient boundary value problems. Results indicate that with proper depths of the point masses, point-mass harmonic analysis could recover an earth gravity field model at a higher precision which is a little better than that from the generalized torus harmonic analysis.


Chen H.,Center for Engineering Design and Research under the Headquarters of General Equipment | Liu C.,Huazhong University of Science and Technology | Shu C.,Huazhong University of Science and Technology | Chang H.,Huazhong University of Science and Technology | Shu S.,Huazhong University of Science and Technology
Zhongnan Daxue Xuebao (Ziran Kexue Ban)/Journal of Central South University (Science and Technology) | Year: 2016

The thermodynamic parameters variation in the stagnation state of the cryogenic fluid near the globe valve in the delivery pipelines was investigated. A mathematical model of the flow process of conveying pipelines was presented using the finite volume method. The influences of the pipelines geometry and the heat leakage on the cryogenic fluid in the state of stagnation were analyzed, and the dominant reasons of the temperature rise before the globe valve were investigated. The results show that the temperature rise can be reduced by decreasing the pipeline length, the value heat leakage, and increasing the pipe wall heat leakage properly. This work can be applied as a design reference for improvement of the rocket fuel filling system and other new systems. © 2016, Central South University Press. All right reserved.


Zhang T.,Center for Engineering Design and Research under the Headquarters of General Equipment | Wang S.Z.,Center for Engineering Design and Research under the Headquarters of General Equipment | Dong C.H.,Center for Engineering Design and Research under the Headquarters of General Equipment | Han L.,Zhengzhou University
Material Science and Environmental Engineering - Proceedings of the 3rd annual 2015 International Conference on Material Science and Environmental Engineering, ICMSEE 2015 | Year: 2016

Efficient solid adsorbents are provided for the removal of chlorine in air. The major materials include Ca (OH)2, NaOH and a small amount of additives. The agents were characterized by Scanning Electron Microscopy (SEM) and nitrogen adsorption-desorption method, etc. The results show that the optimum chlorine removing agent with a weight ratio of 1Ca (OH)2: 1 NaOH has the largest surface area and largest pore volume. The removal efficiency was determined and the results indicate that removal efficiency of the optimum agent can reach almost 100% within 10 min. © 2016 Taylor and Francis Group, London.


Nie X.-T.,China Aerodynamics Research And Development Center | Huang K.,Center for Engineering Design and Research under the Headquarters of General Equipment
Zhendong yu Chongji/Journal of Vibration and Shock | Year: 2010

Ideal models are usually used in dynamic analysis of a seeker servo mechanism, and the influences of random factors, such as, design tolerance, mismatching tolerance and wear on the dynamic behavior of the system are seldom taken into account. So it is difficult to describe the actual dynamic behavior of the system correctly. Here, a nonlinear dynamic model of the servo mechanism under random excitation was established. The FPK (Fokker - Planck - Kolmogorov) equations of the system were deduced and solved using the stochastic averaging method and the point-interpolation meshless method synthetically. Then, the random dynamic response was calculated and the influence of the friction parameter on the system random response characteristic was studied. The results obtained could provide a theoretic foundation for evaluating dynamic behavior of a servo mechanism.


Chen H.,Center for Engineering Design and Research Under the Headquarters of General Equipment | He S.,Huazhong University of Science and Technology | Chang H.,Huazhong University of Science and Technology | Shu S.,Huazhong University of Science and Technology
Huazhong Keji Daxue Xuebao (Ziran Kexue Ban)/Journal of Huazhong University of Science and Technology (Natural Science Edition) | Year: 2015

For the diving process, imcompressiable Navier-Stokes equations, together with phase field equation, were used to track the interface and flow characteristic which took into account buoyancy and evaporation of cryogenic liquid in water. The mathematical models were combined to predict the penetration depth and evaporation rate of cryogenic liquid in water. Numerical studies have been taken under the conditions of various of initial velocities and initial diameters of liquid nitrogen with these models. The results show that the diameters and the velocities have a great influence on penetration depth, cryogenic shape and evaporation rate. For the relatively small diameter, all liquid nitrogen evaporates in water and only vapor comes out of water. For the relatively large diameter, not all liquid nitrogen evaporates in water and some cryogenic liquid may come out of water. ©, 2015, Huazhong University of Science and Technology. All right reserved.


Zhan Y.,Zhengzhou University | Zheng Y.,Zhengzhou University | Zhang C.,Zhengzhou University | Luo Y.,Zhengzhou University | Wang K.,Center for Engineering Design and Research under the Headquarters of General Equipment
Cehui Xuebao/Acta Geodaetica et Cartographica Sinica | Year: 2016

A fish-eye camera calibration model is presented, basic observations of which consist of both half angle of view and azimuth. Rodrigues matrix is introduced into the model, and three Rodrigues parameters instead of Euler angles are used to represent elements of exterior orientation in order to simplify the expressions and calculations of observation equations. The new model is compared with the existing models based on half angle of view constraint by actual star-map data processing, and the results indicate that the model is superior to control the azimuth error, while slightly inferior to constrain the error of half angle of view. It is advised that radial distortion parameters should be determined by the model based on half angle of view constraint at first, and other camera parameters should be calculated by the new model. © 2016, Surveying and Mapping Press. All right reserved.

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