2015 Vol. 41, No. 11

Display Method:
Coal and rock recognition method based on low frequency component characteristics of discrete cosine transform and learning vector quantizatio
SUN Jiping, LIU Jianqiao
2015, 41(11): 1-6. doi: 10.13272/j.issn.1671-251x.2015.11.001
Abstract:
To solve problems of small application scope and low recognition accuracy rate of existing coal and rock recognition methods, discrete cosine transform (DCT) is used to process coal and rock image blocks. DCT transform coefficients of each image block are arranged in the form of “Z” shape to express vector of image blocks. There are two extraction methods of coal and rock image features: coal and rock images feature vectors are constituted by average value of each image block vector and variance of all image blocks vector, and the feature vectors are expressed through cascading image block vector by the order of DCT transform of image block. Learning vector quantization neural network is used for coal and rock recognition. Recognition accuracy of the two feature extraction methods both achieves 96.67%. The proposed coal and rock recognition method improves recognition accuracy of 3.3% than Haar wavelet method and 5.8% than Daubechies wavelet method.
R/S analysis of gas emission in coal mine underground tunnel
ZHANG Pengxiang, HAN Zhenli, LI Qingsong, ZHU Quanjie, HENG Xianwei, ZHANG Shujin
2015, 41(11): 7-10. doi: 10.13272/j.issn.1671-251x.2015.11.002
Abstract:
In order to grasp changes of the danger of coal and gas outburst, factors of coal seam gas emission were analyzed, R/S analysis method was used to study gas emission of coal mine tunnel, and the following conclusion was obtained: gas emission time series have fractal characteristics, when it is detected that Hurst index is decreasing and has great volatility, it indicates abnormal gas emission will occur, so certain safety precautions should be taken in advance.
Determination method of mine microseism source depth under latitude and longitude coordinates
WANG Meng, WANG Guofu, ZHANG Faquan, HUANG Guiqiang
2015, 41(11): 10-13. doi: 10.13272/j.issn.1671-251x.2015.11.003
Abstract:
For problems of difficult determination and big error of mine microseism source depth, a determination method of microseism source depth was proposed by only using travel time of P wave. Firstly, plane coordinates and start time of microseism source are calculated through an improved linear location method. Secondly, based on epicentral distance and travel time of microseism between microseism source and station, TD mode fitting is conducted firstly and DT mode fitting is conducted after eliminating error data. Finally, microseism source depth is determined according to intercept of fitting straight line. The actual application results show that the method can effectively reduce interference of error measured data and improve measuring accuracy of microseism source depth.
Remote monitoring system of shearer based on Quest3D and PLC
WU Haiyan, WANG Tianlong, ZHANG Xuhui, MAO Qinghua, DU Yuyang, GAO Baizhan, MA Hongwei
2015, 41(11): 14-17. doi: 10.13272/j.issn.1671-251x.2015.11.004
Abstract:
In view of some problems of video monitoring of shearer and two-dimensional plane monitoring such as blurring monitoring images, inability to display running status of shearer real-timely and so on, a kind of remote monitoring system of shearer was put forward which was based on PLC and Quest3D. The system uses PLC, computer, remote console and others to compose hardware platform, uses Quest3D software to realize virtual monitoring platform, and realizes communication between software and hardware by data interface of virtual reality and FX2N PLC programming port. The test result shows that the system can realize real-time display of running status parameter of shearer and remote control of shearer.
Research on monitoring technology of surrounding rock stress based on fiber grating
LI Huwei, FANG Xinqiu, LIANG Minfu, XUE Guangzhe
2015, 41(11): 17-20. doi: 10.13272/j.issn.1671-251x.2015.11.005
Abstract:
In view of problem of low monitoring efficiency, poor authenticity and accuracy of surrounding rock stress monitoring, a surrounding rock stress monitoring system which can realize real-time online monitoring and long-term monitoring was proposed according to sensor principle and mechanical characteristics of fiber grating. The system applies fiber grating sensing technology to real-time monitoring of surrounding rock stress, and has advantages of high precision, small error and strong anti-interference ability.
Power allocation and capacity optimization of multi-relay cooperative communication system in tunnel
ZHAI Wenyan, SUN Yanjing, LI Song, LIANG Dihui
2015, 41(11): 21-25. doi: 10.13272/j.issn.1671-251x.2015.11.006
Abstract:
The multi-relay cooperative communication system model in rectangular tunnel based on multimode channel model was established, and the channel capacity calculation formulas of multi-relay cooperative communication system in amplify and forward mode and decode and forward mode were given. Under the circumstance of limited power in tunnel, optimal power allocation method of amplify and forward multi-relay cooperative communication system based on genetic algorithm and multiple KKT optimal power allocation method of multi-relay cooperative communication system in decode and forward were proposed to optimize the channel capacity. Simulation results show that the proposed optimal power allocation methods can improve channel capacity of the tunnel multi-relay cooperative communication system.
A new accurate localization method in underground tunnel of coal mine
YOU Chunxia, ZHANG Shen, HU Qingsong, ZHAI Yanrong
2015, 41(11): 26-30. doi: 10.13272/j.issn.1671-251x.2015.11.007
Abstract:
In view of problem of low accuracy of localization system based on electromagnetic wave in underground coal mine, an accurate localization method based on visible light communication in underground coal mine was proposed. The method uses visible light communication technology and adopts own situation information of LED light source to compute the distance between mobile terminal and specific LED light source according to received light signal intensity of mobile terminal, so as to locate by two-dimension positioning and three-dimension positioning. The positioning accuracy is a few centimeters with the method. The method overcomes multipath interference and improves localization quality compared with other localization method of electromagnetic wave.
Feature extraction method for human ear image and its application in miner identificatio
WU Yunxia, ZHANG Haopeng, DU Dongbi
2015, 41(11): 30-34. doi: 10.13272/j.issn.1671-251x.2015.11.008
Abstract:
In view of problem of big error of existing features extraction method for ear image adopting geometrical shape extraction and algebra extraction, a novel feature extraction method for human ear image was proposed to apply to miner identification. The method uses three-scale canny operator to extract image edges of the helix, and adopts convex hull algorithm to extract key points of ear edge image, uses outer contour search algorithms to extract outer contour of ear image; constructs the ear image feature vector with the length ratio of point to the pole distance of outer ear contour and human ear in epipolar plane, which solves the problem of big error of ear geometry feature. The identification accuracy is 96% with the method to extract human ear image feature for miner identification.
Research of personnel tracking algorithm for coal mine substation based on CamShift and particle filter
HAO Jianhua
2015, 41(11): 35-38. doi: 10.13272/j.issn.1671-251x.2015.11.009
Abstract:
The paper proposed a personnel tracking algorithm for coal mine substation based on CamShift and particle filter and made experiments. The experiments show that the proposed algorithm can improve accurate rate of tracking of moving target.
A fault diagnosis method of fault indicator based on the worst principle
ZHENG Guohua, HUANG Duo, WANG Junfeng, WU Xiaobin, XU Weiqian, SUN Zhenye, ZHANG Wei
2015, 41(11): 39-43. doi: 10.13272/j.issn.1671-251x.2015.11.010
Abstract:
In order to solve problem of fault diagnosis of fault indicator for distribution power network in mining area in imperfect information, the concept of the minimum fault diagnosis area was put forward. The fault diagnosis mathematical model of fault indicator based on the concept of the minimum fault diagnosis area was proposed, and a fault diagnosis method of fault indicator based on the worst principle and the mathematical model was proposed. The method recognizes and corrects short circuit fault signals and the fault grounding signal through the worst principle, and solves fault diagnosis problem such as false negatives and false positives of fault signal in imperfect information. The running example proves the practicability and correctness of the method.
Research of routing protocol of wireless sensor network in underground strip environment
DONG Lihong, LU Xiangyu
2015, 41(11): 43-47. doi: 10.13272/j.issn.1671-251x.2015.11.011
Abstract:
For static strip distribution characteristic of wireless sensor networks nodes used in underground pressure monitoring system, the minimum hop count routing protocol was taken as a research object and improved in route creation phase, data transfer phase and maintenance update phase. An improved routing protocol named the minimum hop count based on node energy classification was put forward. The improved routing protocol reduces control group and redundancy of data transmission path by grading the node energy. The simulation result show that the improved routing protocol has obvious advantages in extending life period of network, reducing average end delay of data packet and reducing percentage of control packets over the traditional directed diffusion routing protocol and the minimum hop count routing protocol.
A dynamic image enhancement method for mine
YANG Yong, YUE Jianhua, LI Yuliang, WANG Qingfei
2015, 41(11): 48-52. doi: 10.13272/j.issn.1671-251x.2015.11.012
Abstract:
Aiming at noise, low image grey and little gray difference of dynamic monitoring image of coal mine, a dynamic image enhancement method was proposed. Original image is processed by an improved histogram equalization method firstly and then dealt with illumination estimatation. The illumination image is normalized, while reflected light image is revised by nonlinear dynamic gain. The experimental results by use of monitoring image from mine locomotive management system show that the method has better image processing effect.
Particle velocity detection technology based on Manhattan distance method
CHEN Jiange
2015, 41(11): 52-55. doi: 10.13272/j.issn.1671-251x.2015.11.013
Abstract:
It was proposed that Manhattan distance method was used for detecting velocity of solid particle in gas-solid two-phase flow, and detection principle was introduced. A delay estimation algorithm was proposed to save data storage space of processor. An experimental system was built and collected signals by oscillograph were analyzed by cross-correlation theory detection method and Manhattan distance method separately. The analysis result shows that Manhattan distance method has better stability and reliability.
Monitoring method of slope based on fringe projection and two-dimensional principal component analysis
ZHAO Qian, XU Xinya
2015, 41(11): 56-59. doi: 10.13272/j.issn.1671-251x.2015.11.014
Abstract:
In view of problems of less monitoring points, low resolution, long measurement cycle of existing slope monitoring method, a monitoring method of slope based on fringe projection and two-dimensional principal component analysis was proposed in order to real-timely monitor settlement of slope and effectively restrain false alarm. Firstly, the method uses triple-frequency color fringe projection profilometry to obtain height information of observed slope quickly and accurately. Then it uses two-dimensional principal component analysis to analyze the height information and simplify computation amount. Finally, it adopts Euclidean distance corresponding to the measured slope position of different times to judge whether the slope false alarm occurs. The experiment results show that the monitoring method can effectively monitor false alarm of slope, and has a good performance of real-time and robustness.
Research of a separation method of positive and negative sequence component in coal mine power supply system
HUANG Zhichao, LIAO Zhijian, HUANG Xiangli
2015, 41(11): 60-64. doi: 10.13272/j.issn.1671-251x.2015.11.015
Abstract:
In view of problem that negative sequence components in unbalanced coal mine power system affect stable running of electric locomotive, and in order to satisfy control strategy of three-phase PWM rectifier, the characteristics of asymmetric signal under rotating coordinate system and the principle of enhanced notch filter were studied, and a separation method of positive and negative sequence component was presented. The rotating-coordinate system was used to transform the asymmetric signal and the enhanced adaptive notch filter was used to filter the two-times frequency signal in the method. The Matlab/Simulink simulation results show that the method can extract DC value of positive and negative sequence components in asymmetric signal precisely and quickly and can filter some harmonic waves.
Current leakage protection method of coal mine based on time-sharing ratio of phase current amplitude
CHEN Zhaoye, MA Xinghe, PEI Zhiqiang, ZHANG Junwei, DONG Hongling
2015, 41(11): 64-68. doi: 10.13272/j.issn.1671-251x.2015.11.016
Abstract:
For the problem that failure current was small of grounding point of neutral point grounding system grounded by arc suppression coil when single-phase ground fault occurs, the paper proposed a kind of current leakage protection method of coal mine based on time-sharing ratio of phase current amplitude. The method obtains summation ratio of mutual integral of transient current and steady-state phase current by sampling and calculation, and conducts leakage protection of transient current and steady-state phase current respectively, then makes judge conclusion according to the larger phase current ratio, so as to automatically select the fault line and trip. The Matlab simulation results show that the method can effectively achieve leakage protection, and the line selection results are accurate and reliable.
Study on hierarchical model of mine emergency command platform system
ZHENG Wanbo, WU Yanqing, LIU Dan, LI Xianming
2015, 41(11): 69-73. doi: 10.13272/j.issn.1671-251x.2015.11.017
Abstract:
In view of problems of lack of theoretical system support, poor ability of coordination and difficulty of connecting with different platforms existed in mine emergency command platform in China, combining systems engineering and ICS framework, a hierarchical model of mine emergency command platform system was constructed based on six aspects (mission, task, combat capability, combat systems, platform/facility and system) of four basic levels (target and mission of systems, systems service, system target and system behavior), which could provide reference for qualitative and quantitative analysis of mine emergency command platform system.
Current situation of coal mine ventilation system and design of intelligent ventilation system
YANG Jie, ZHAO Liangang, QUAN Fang
2015, 41(11): 74-77. doi: 10.13272/j.issn.1671-251x.2015.11.018
Abstract:
The paper analyzed current situation of application of existing mine ventilation system, pointed out the shortages of the current ventilation system. It gave research method of intelligent ventilation system on the basis of industrial 4.0 concept, and proposed design scheme of an intelligent ventilation system based on field bus technology according to the research method. The system adopts modular design method to design several independent modules, such as data collection, analysis and processing, decision-making execution subsystem, uses Ethernet technology to transmit data, and uses the CAN bus network to realize control function, which can realize air supply according to demand and adjustable air volume in advance.
Design of PLC control system of uniform velocity temperature rise based on idea of devide and conquer
WEI Fupeng, QIAO Tiezhu
2015, 41(11): 78-80. doi: 10.13272/j.issn.1671-251x.2015.11.019
Abstract:
PLC control system of uniform velocity temperature rise based on idea of devide and conquer was designed based on considerations of practicability, low-cost and high-precision control. The system devided the heating process into multi sub-units, and calculated heating time and set temperature for each sub-unit, and finally execute heating sub-unit successively. Least squares method was used to fit temperature curve, and the error of temperature rise rate between fitting temperature curve and theoretical temperature curve was 3.62%, it indicated that the system has high precision control and small error of temperature rise rate.
Fuzzy comprehensive line selection method of resonance grounding fault in coal mine
MA Chunyan, GONG Ying
2015, 41(11): 81-84. doi: 10.13272/j.issn.1671-251x.2015.11.020
Abstract:
For failure of fault line selection methods based on steady-state component in resonance grounding system, three kinds of methods were analyzed from the perspective of transient component including zero-sequence energy method, wavelet transform method and enhancing wavelet packet method. Fuzzy comprehensive evaluation method was introduced to integrate the three kinds of methods, and AHP method was used to determine weights of the three methods. The simulation conclusion shows that the reliability of zero-sequence energy method and enhancing wavelet packet method are better, but wavelet transform methods has false conclusion, with poor reliability; The fuzzy comprehensive evaluation is not interfered by other error signal, and gives correct conclusion, which has strong reliability.