Liu Z.,Hubei Engineering University
Nature Communications | Year: 2017
Controlled fabrication of metallic nanostructures plays a central role in much of modern science and technology, because changing the dimensions of a nanocrystal enables tailoring of its mechanical, electronic, optical, catalytic and antibacterial properties. Here we show direct superplastic nanoimprinting (SPNI) of crystalline metals well below their melting temperatures, generating ordered nanowire arrays with aspect ratios up to ~2,000 and imprinting features as small as 8 nm. Surface-enhanced Raman scattering (SERS) spectra reveal strongly enhanced electromagnetic signals from the prepared nanorod arrays with sizes up to ~100 nm, which indicates that our technique can provide an ideal way to fabricate robust SERS substrates. SPNI, as a one-step, controlled and reproducible nanofabrication method, could facilitate the applications of metal nanostructures in bio-sensing, diagnostic imaging, catalysis, food industry and environmental conservation. © The Author(s) 2017.
Mao W.,Hubei Engineering University
Applied Energy | Year: 2017
Belt conveyors and crushers are always assembled in series to form coal conveying systems; reasonably, this paper takes them as a whole for energy efficiency optimization. The energy models of the key energy consuming devices, belt conveyors and crushers, are firstly constructed. They are then employed to formulate an open loop energy efficiency optimization problem for the studied coal conveying systems. The coal feed rate, belt speed and crusher rotational speed are taken as the optimization variables; and, the energy cost, with consideration of time-of-use (TOU) tariff, is formulated as the objective function. Next, basing on the above open loop optimization problem, a closed-loop model predictive control (MPC) strategy is constructed. The MPC strategy has the ability to deal with various disturbances with its feedback correction and receding horizon optimization mechanisms. A coal conveying system in a coal-fired power plant is taken as a case study for verification of the two strategies. The open loop optimization and MPC strategies are investigated respectively for comparison studies. The results show that, unlike the open loop optimization, the MPC strategy can deal with the disturbances of coal consumption forecasting, the disturbances of belt feeding rate and the disturbances of mean particle size of feeding coal effectively. The MPC strategy can considerably improve the energy efficiency of the whole coal conveying system while satisfying all the constraints. Its robustness and adaptability are verified through the comparison studies. © 2017 Elsevier Ltd
Song R.,Hubei Engineering University
MATEC Web of Conferences | Year: 2017
Cu is widely used to contact materials because of its excellent electrical conductivity and economical efficiency, but its high temperature strength is slightly insufficient. In this paper, the less layers of graphene oxide were dispersed in deionized water by ultrasonic treatment, then copper acetate aqueous solution was added to the graphene oxide suspension with mixing. Then add NaOH aqueous solution into the blend solution. With graphene as a substratum, Cu (OH)2 precipitations were generated so that a molecular level dispersion can be achieved. The precipitations were isolated by filtering, rinsing and drying, and then, these powders were reduced at 400°C under a hydrogen atmosphere to form the homogeneously dispersed Cu/graphene composite powders. Sinter powders by spark plasma sintered and we obtained Cu contact materials strengthened by graphene. Under the sintering pressure of 250 Mpa, the hardness of Cu/graphene composite was 171.4 HV, which was 4.3 times than that of annealed copper; the electrical conductivity of Cu/graphene only decreased 5% and can still meet the contact demand. © The Authors, published by EDP Sciences.
Zhou Q.,Hubei Engineering University
Lecture Notes in Geoinformation and Cartography | Year: 2017
OpenStreetMap (OSM) is a free source of spatial data based on crowd-sourcing. Although OSM data are widely used in applications such as the generation of 3D models, routing and navigation, the quality issue is still one of the significant concerns when using these data. Extensive studies have focused on assessing the quality, especially the positional accuracy, of OSM data. One method for assessing accuracy is the buffering approach where a buffer is created around a validated road network using a predefined buffer radius. The percentage of OSM road lengths that lie within this buffer is then calculated. While existing studies have used the buffering approach, the method itself has not been evaluated either theoretically and experimentally. It is found that the percentage of OSM road length calculated based on the buffering approach may be imprecise if the validated road network and the OSM road network are not matched one-to-one. Therefore, this study suggests that it is necessary to first match the OSM road network with the validated road network before using the buffering approach. © Springer International Publishing AG 2017.
Zeng C.,Hubei Engineering University |
Shen H.,Hubei University |
Zhang L.,Hubei Engineering University
Remote Sensing of Environment | Year: 2013
Since the scan line corrector (SLC) of the Landsat Enhanced Thematic Mapper Plus (ETM. +) sensor failed permanently in 2003, about 22% of the pixels in an SLC-off image are not scanned. To improve the usability of the ETM. + SLC-off data, we propose an integrated method to recover the missing pixels. The majority of the degraded pixels are filled using multi-temporal images as referable information by building a regression model between the corresponding pixels. When the auxiliary multi-temporal data cannot completely recover the missing pixels, a non-reference regularization algorithm is used to implement the pixel filling. To assess the efficacy of the proposed method, simulated and actual SLC-off ETM. + images were tested. The quantitative evaluations suggest that the proposed method can predict the missing values very accurately. The method performs especially well in edges, and is able to keep the shape of ground features. According to the assessment results of the land-cover classification and NDVI, the recovered data are also suitable for use in further remote sensing applications. © 2013 Elsevier Inc.
Gerke M.,University of Twente |
Xiao J.,Hubei Engineering University
ISPRS Journal of Photogrammetry and Remote Sensing | Year: 2014
Automatic urban object detection from airborne remote sensing data is essential to process and efficiently interpret the vast amount of airborne imagery and Laserscanning (ALS) data available today. This paper combines ALS data and airborne imagery to exploit both: the good geometric quality of ALS and the spectral image information to detect the four classes buildings, trees, vegetated ground and sealed ground. A new segmentation approach is introduced which also makes use of geometric and spectral data during classification entity definition. Geometric, textural, low level and mid level image features are assigned to laser points which are quantified into voxels. The segment information is transferred to the voxels and those clusters of voxels form the entity to be classified. Two classification strategies are pursued: a supervised method, using Random Trees and an unsupervised approach, embedded in a Markov Random Field framework and using graph-cuts for energy optimization. A further contribution of this paper concerns the image-based point densification for building roofs which aims to mitigate the accuracy problems related to large ALS point spacing.Results for the ISPRS benchmark test data show that to rely on color information to separate vegetation from non-vegetation areas does mostly lead to good results, but in particular in shadow areas a confusion between classes might occur. The unsupervised classification strategy is especially sensitive in this respect. As far as the point cloud densification is concerned, we observe similar sensitivity with respect to color which makes some planes to be missed out, or false detections still remain. For planes where the densification is successful we see the expected enhancement of the outline. © 2013 International Society for Photogrammetry and Remote Sensing, Inc. (ISPRS).
Yang C.,Hubei Engineering University
Dianwang Jishu/Power System Technology | Year: 2013
Firstly the application requirements of emergency command of smart grid for overall real-time perception, intelligent analysis and multidimensional visualization of environment and operation security of the grid as well as the integrated services with different applications are analyzed in depth, and by use of internet of things (IoT) technology it is proposed to implement genetic algorithm based fault location for distribution network and to implement automatic sensing, identification, tracking and command of deployment and allocation of emergency personnel, goods and materials during overall process. By use of spatial information technologies and integrating with symmetric triangular fuzzy number (STFN), the analog computation of optimal emergency logistics path in emergency logistics is performed, and an emergency resource allocation scheme based on geographic information system (GIS) is established. Based on IoT technology and spatial information technologies, a visual emergency command and support platform, in which the disaster monitoring, early warning, querying and analysis, resource allocation and command and decision-making are integrated, is designed and constructed. Finally, a case of the construction of a grid emergency command system of a certain provincial power company and its practical application effects is analyzed.
Yu Y.-S.,Hubei Engineering University
Applied Mathematics and Mechanics (English Edition) | Year: 2012
Young's equation is a fundamental equation in capillarity and wetting, which reflects the balance of the horizontal components of the three interfacial tensions with the contact angle (CA). However, it does not consider the vertical component of the liquid-vapor interfacial tension (VCLVIT). It is now well understood that the VCLVIT causes the elastic deformation of the solid substrate, which plays a significant role in the fabrication of the microfluidic devices because of the wide use of the soft materials. In this paper, the theoretical, experimental, and numerical aspects of the problem are reviewed. The effects of the VCLVIT-induced surface deformation on the wetting and spreading, the deflection of the microcantilever, and the elasto-capillarity and electroelasto-capillarity are discussed. Besides a brief review on the historical development and the recent advances, some suggestions on the future research are also provided. © Shanghai University and Springer-Verlag.
Zhong Y.,Hubei Engineering University |
Zhang L.,Hubei Engineering University
Pattern Recognition | Year: 2013
A new sub-pixel mapping strategy inspired by the clonal selection theory in artificial immune systems (AIS), namely, the clonal selection sub-pixel mapping (CSSM) framework, is proposed for the sub-pixel mapping of remote sensing imagery, to provide detailed information on the spatial distribution of land cover within a mixed pixel. In CSSM, the sub-pixel mapping problem becomes one of assigning land-cover classes to the sub-pixels while maximizing the spatial dependence by the clonal selection algorithm. Each antibody in CSSM represents a possible sub-pixel configuration of the pixel. CSSM evolves the antibody population by inheriting the biological properties of human immune systems, i.e., cloning, mutation, and memory, to build a memory cell population with a diverse set of locally optimal solutions. Based on the memory cell population, CSSM outputs the value of the memory cell and finds the optimal sub-pixel mapping result. Based on the framework of CSSM, three sub-pixel mapping algorithms with different mutation operators, namely, the clonal selection sub-pixel mapping algorithm based on Gaussian mutation (G-CSSM), Cauchy mutation (C-CSSM), and non-uniform mutation (N-CSSM), have been developed. They each have a similar sub-pixel mapping process, except for the mutation processes, which use different mutation operators. The proposed algorithms are compared with the following sub-pixel mapping algorithms: direct neighboring sub-pixel mapping (DNSM), the sub-pixel mapping algorithm based on spatial attraction models (SASM), the BP neural network sub-pixel mapping algorithm (BPSM), and the sub-pixel mapping algorithm based on a genetic algorithm (GASM), using both synthetic images (artificial and degraded synthetic images) and real remote sensing imagery. The experimental results demonstrate that the proposed approaches outperform the previous sub-pixel mapping algorithms, and hence provide an effective option for the sub-pixel mapping of remote sensing imagery. © 2013 Elsevier Ltd.
Feng C.-F.,Hubei Engineering University
Nonlinear Dynamics | Year: 2010
In this paper, we investigate the projective synchronization between two different time-delayed chaotic systems. A suitable controller is chosen using the active control approach. We relax some limitations of previous work, where projective synchronization of different chaotic systems can be achieved only in finite dimensional chaotic systems, so we can achieve projective synchronization of different chaotic systems in infinite dimensional chaotic systems. Based on the Lyapunov stability theory, we suggest a generic method to achieve the projective synchronization between two different time-delayed chaotic systems. The validity of the proposed method is demonstrated and verified by observing the projective synchronization between two well-known time-delayed chaotic systems; the Ikeda system and Mackey-Glass system. Numerical simulations fully support the analytical approach. © 2010 Springer Science+Business Media B.V.