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Interference cancellation method based on space-time code for MIMO interference channel

The Journal of China Universities of Posts and Telecommunications 2016年第3期23卷 45-50页

作者： Yang Dong Tian Xinji Opening Project of Key Laboratory of Mine Informatization Henan Polytechnic University School of Computer Science and Technology Henan Polytechnic University

We investigate how to cancel interference by using space time code and codeword space alignment for multiple-input multiple-output （MIMO） Y channel consisting of three users and a relay. All the nodes adopt Alamouti code. During the multiple access （MA） stage, two codewords within each reciprocal codeword pair are aligned through pre-coding. The relay decodes the elements of each codeword pair using the orthogonal property of effective channel matrix of Alamouti codeword. During the broadcast （BC） stage, the interference between codeword pairs at each user is eliminated by the orthogonal property of effective channel matrix of Alamouti codeword, instead of the interference alignment （IA） pre-coding. Thus, channel state information （CSI） is not required during the BC stage, which greatly reduce the amount of feedback.

关键词： MIMO Y channel space-time code space alignment feedback amount

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Effect of rock composition microstructure and pore characteristics on its rock mechanics properties

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International Journal of Mining Science and Technology 2018年第2期28卷 303-308页

作者： Li Huamin Li Huigui Wang Kailin Liu Chuang School of Energy Science and Engineering Henan Polytechnic University Opening Project of Key Laboratory of Deep Mine Construction Henan Polytechnic University

This paper is to study the influence of composition, microstructure and pore characteristics on the rock mechanical properties. Five kinds of sandstone compositions were analyzed by using X-ray diffraction instrument. And the microstructure was observed by using scanning electron microscope. Then the pore distribution characteristic was investigated by using the low field nuclear magnetic resonance equipment. Finally, the uniaxial compression test was carried out to investigate the mechanical characteristics by using RMT150C mechanics experimental system and the uniaxial compressive strength, Poisson's ratio and elastic modulus were obtained. Compared to the analysis of the composition, structure and pore distribution and mechanical properties of the five kinds of sandstones, the relationship among composition,structure, pore distribution and mechanical properties was obtained. The results show that the composition, microstructure, pore distribution and mechanical properties of sandstone are closely *** the decrease of feldspar and quartz particles, the compressive strength and elastic modulus increase, while the porosity decreases.

关键词： Mechanical characteristics Pore characteristics Microstructure Composition Scanning electron microscope

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An improved data placement strategy in a heterogeneous Hadoop cluster

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Open Cybernetics and Systemics Journal 2014年第1期8卷 957-963页

作者： Zhao, Wentao Meng, Lingjun Sun, Jiangfeng Ding, Yang Zhao, Haohao Wang, Lina School of Computer Science and Technology Henan Polytechnic University Jiaozuo454000 China Opening Project of Key Laboratory of Mine Informatization Henan Polytechnic University JiaozuoHenan454000 China

Hadoop Distributed File System (HDFS) is designed to store big data reliably, and to stream these data at high bandwidth to user applications. However, the default HDFS block placement policy assumes that all nodes in the cluster are homogeneous, and randomly place blocks without considering any nodes’ resource characteristics, which decreases self-adaptability of the system. In this paper, we take account nodes heterogeneities, such as utilization of nodes’ disk space, and put forward an improved blocks placement strategy for solving some drawbacks in the default HDFS. The simulation experiments indicate that our improved strategy performs much better not only in the data distribution but also significantly saves more time than the default blocks placement. © Zhao et al.

关键词： Big data

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Stability analysis of tunnel-slope coupling based on genetic algorithm

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Journal of Engineering Science and Technology Review 2015年第3期8卷 65-70页

作者： Luo, Tao Wang, Shuren Liu, Xiliang Zou, Zhengsheng Cao, Chen Opening Project of Key Laboratory of Deep Mine Construction Henan Polytechnic University Jiaozuo454003 China School of Civil Mining and Environmental Engineering University of Wollongong Wollongong2522 Australia

Subjects in tunnels, being constrained by terrain and routes, entrances and exits to tunnels, usually stay in the terrain with slopes. Thus, it is necessary to carry out stability analysis by treating the tunnel slope as an entity. In this study, based on the Janbu slices method, a model for the calculation of the stability of the original slope-tunnel-bank slope is established. The genetic algorithm is used to implement calculation variables, safety coefficient expression and fitness function design. The stability of the original slope-tunnel-bank slope under different conditions is calculated, after utilizing the secondary development function of the mathematical tool MATLAB for programming. We found that the bearing capacity of the original slopes is reduced as the tunnels are excavated and the safety coefficient is gradually decreased as loads of the embankment construction increased. After the embankment was constructed, the safety coefficient was 1.38, which is larger than the 1.3 value specified by China's standards. Thus, the original slope-tunnel-bank slope would remain in a stable state. © 2015 Kavala Institute of Technology.

关键词： Genetic algorithms

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An improved data placement strategy in a heterogeneous Hadoop cluster

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Open Cybernetics and Systemics Journal 2015年第1期9卷 792-798页

关键词： Big data

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An improved underground location algorithm based on convex sets of RSSI

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Open Cybernetics and Systemics Journal 2016年 10卷 163-171页

作者： Zhao, Wentao Cheng, Yafei Meng, Lingjun Wang, Chunchun Wang, Lina School of Computer Science and Technology Henan Polytechnic University Jiaozuo454000 China Opening Project of Key Laboratory of Mine Informatization Henan Polytechnic University JiaozuoHenan454000 China

Location algorithm based on fingerprint has been applied to underground tunnel of coal mines. However, obvious and unignorable errors will occur if reference locations are selected sparsely when detecting unknown points, which may make it difficult for locating people in coal mines. Hence, an underground location algorithm based on convex sets of Received Signal Strength Indication (RSSI) is proposed in this paper. Many reference location points are deployed at the experimental tunnel every 5m both 2 sides as depicted in Fig. 5) shows, then a reference location can be randomly selected. Firstly, calculate the Euclidean distance between unknown points and reference locations in a fingerprint database established by using RSSI value that de-noised by the Kalman filter algorithm. Secondly, select several reference locations that mostly match with unknown points, construct a convex. Finally, take the coordinates of centroid of the convex as the coordinates of the unknown points. The simulation experiments indicate that the proposed algorithm locates unknown points with higher accuracy than the traditional one based on fingerprint. © Zhao et al.

关键词： Location

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Correlativity between coal permeability and strain in quasi-plane strain state

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Journal of Coal Science & Engineering(China) 2013年第4期19卷 493-499页

作者： Bao-Bin GAO Yun-Peng LIU Stage Key Laboratory Cultivation Base for Gas Geology and Gas Control (Henan Polytechnic University) Jiaozuo 454000 China Opening Project of Key Laboratory of Deep Mine Construction Henan Polytechnic University Jiaozuo 454000 China School of Safety Science and Engineering Henan Polytechnic University Jiaozuo 454000 China

To simulate the variety of big coal sample permeability during the rupture process under quasi-plane strain state, a series of experiments have been performed by a set of self-made coal-gas coupling test system. The test results indicate that the development trend between the permeability rate-strain curve and the stress-strain curve of big coal sample is almost consistent. The permeability rate-strain curve is general hysteretic to stress-strain curve, indicating the close relativity between the evolvement of damage and the development of permeability rate. However, there is time interval between them and the perme- ability rate peaks value when the sample reaches the softened stage after the peak stress. Based on the characteristics of per- meability rate-strain curve, three stages were plotted out： the stage before minimum permeability rate （/co）, the stage between minimum and maximum of permeability rate and the stage after the maximum permeability rate （kmax）. According to the three stages of permeability rate, the segmental curve equations of permeability rate-strain were fitted： the first stage can be fitted with negative exponential function; the second stage can be fitted with Boltzmann equation; and the last stage can be fitted with multinomial equation.

关键词： permeability quasi-plane strain coal-gas coupling test system stress-strain

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Characteristic analysis of pressure-arch of a double-arch tunnel in water-rich strata evolution

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Journal of Engineering Science and Technology Review 2016年第1期9卷 44-51页

作者： Li, C.L. Wang, S.R. Zou, Z.S. Liu, X.L. Li, D.Q. School of Civil Engineering and Mechanics Yanshan University Qinhuangdao066004 China Institute of Urban Construction Hebei Normal University of Science and Technology Qinhuangdao066004 China Opening Project of Key Laboratory of Deep Mine Construction Henan Polytechnic University Jiaozuo454003 China School of Mining Engineering University of New South Wales NSW2502 Australia

It is of importance to analyze the morphological characterization, the evolution process and the skewed effect of pressure-arch of a double-arch tunnel in the water-rich strata. Taking a buried depth 80 m double-arch tunnel as an example, a computational model of the double-arch tunnel was built by using FLAC3D technique. Then considering some aspects including groundwater conditions, tunnel depth, construction sequences and permeability coefficients, the coupling effect of stress field and seepage field in the pressure-arch of the double-arch tunnel was analyzed. The results show that the thickness of the pressure-arch induced by step-by-step excavation and display a step-descent skewed distribution from the left to the right of the double-arch tunnel. The permeability coefficient has a significant influence on the shape and the skewed effect of the pressure arch. The excavation of the bench method has a better arching condition than that of the expanding method. The abtained results provide a basic reference for the rock reinforcement design and safety construction of double-arch tunnels in the water-rich strata. © 2016 Eastern Macedonia and Thrace Institute of Technology. All rights reserved.

关键词： Groundwater

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Reconstruction of different scales of pore-fractures network of coal reservoir and its permeability prediction with Monte Carlo method

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International Journal of Mining Science and Technology 2017年第4期27卷 693-699页

作者： Ni Xiaoming Chen Wenxue Li Zheyuan Gao Xiang School of Energy Science and Engineering School of Civil Engineering Henan Polytechnic University Jiaozuo 454000 China Collaborative Innovation Center of Coalbed Methane and Shale Gas for Central Plains Economic Region Jiaozuo 454000 China Opening Project of Key Laboratory of Deep Mine Construction Henan Polytechnic University Jiaozuo 454000 China Department of Building Civil & Environmental Engineering Concordia University Montreal H3G1M8 Canada china Coal Tunnel Engineering Go. LTD Xuzhou 221000 China

There are millimeter, micron and nanometer scales of pores and fractures in coal to describe different scales of coal pores and fissures communicating path and to quantitatively characterize their permeability. Such information provides an important basis for studying coalbed methane output mechanism. The pores and fissures in a large number of coal samples were observed and counted by scanning electron microscopy and optical microscopy. The probability distribution models of pore-fissure network were then established. Different scales of pore-fissures 2D network models were reconstructed by Monte Carlo method. The 2D seepage models were obtained through assignment zero method and using Matlab software. The effect of permeability on different scale pore-fractures network was obtained by two-dimensional seepage equation. Predicted permeability is compared with the measured ones. The results showed that the dominant order of different scale pore-fractures connected path from high to low is millimeter-sized fractures, seepage pores and micron-size fractures. The contribution of coal reservoir permeability from large to small is millimeter-size fractures, micron-size fractures and seepage pores. Different parameters in different scale pore-fractures are of different influence *** of different scale pore-fractures network can clearly display the connectivity of porefractures, which can provide a basis for selecting migration path and studying gas flow pattern.

关键词： Fractures network Different scales Reconstruction Permeability

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Detection and analysis of height of water flowing fractured zone in underwater mining

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Yanshilixue Yu Gongcheng Xuebao/Chinese Journal of Rock Mechanics and Engineering 2014年第SUPPL.1期33卷 3384-3390页

作者： Gao, Baobin Liu, Yunpeng Pan, Jiayu Yuan, Tian State Key Laboratory Cultivation Base for Gas Geology and Gas Control Henan Polytechnic University Jiaozuo Henan 454000 China Opening Project of Key Laboratory of Deep Mine Construction Henan Polytechnic University Jiaozuo Henan 454000 China School of Safety Science and Engineering Henan Polytechnic University Jiaozuo Henan 454000 China

In order to accurately detect the height of water flowing fractured zone in overlying roof strata after the mining face has been mined and ensure that mining underwater is safe and reliable, empirical formula calculation, downhole plugging drilling section water injection(put) crack measurement system and drilling television detecting system are used to detect the development of water flowing fractured zone. Results show that, using the above three methods respectively, the heights of water flowing fractured zone, which are 25.24-36.50, 26.83-28.33 and 25.50-29.20 m, are obtained. The results verify that using downhole plugging drilling section water injection(put) crack measurement system to detect the height of water flowing fractured zone is reasonable and reliable, and it not only provides a theoretical support for Sitai coal mining underwater, but also provides reference for other coals to detect water flowing fractured zone.

关键词： Water injection

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