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A multi-sensor-based distributed real-time measurement system for glacier deformation
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作者 DONG Han-chuan LIU Shuang +4 位作者 PANG Li-li TAO Zhi-gang FANG Li-de ZHANG Zhong-hua LI Xiao-ting 《Journal of Mountain Science》 SCIE CSCD 2023年第10期2913-2927,共15页
Glacier disasters occur frequently in alpine regions around the world,but the current conventional geological disaster measurement technology cannot be directly used for glacier disaster measurement.Hence,in this stud... Glacier disasters occur frequently in alpine regions around the world,but the current conventional geological disaster measurement technology cannot be directly used for glacier disaster measurement.Hence,in this study,a distributed multi-sensor measurement system for glacier deformation was established by integrating piezoelectric sensing,coded sensing,attitude sensing technology and wireless communication technology.The traditional Modbus protocol was optimized to solve the problem of data identification confusion of different acquisition nodes.Through indoor wireless transmission,adaptive performance analysis,error measurement experiment and landslide simulation experiment,the performance of the measurement system was analyzed and evaluated.Using unmanned aerial vehicle technology,the reliability and effectiveness of the measurement system were verified on the site of Galongla glacier in southeastern Tibet,China.The results show that the mean absolute percentage errors were only 1.13%and 2.09%for the displacement and temperature,respectively.The distributed glacier deformation real-time measurement system provides a new means for the assessment of the development process of glacier disasters and disaster prevention and mitigation. 展开更多
关键词 Glacier disasters distributed deformation measurement MULTI-SENSOR REAL-TIME LoRa Data adaptive.
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2-D distributed pose estimation of multi-agent systems using bearing measurements
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作者 Xu Fang Jitao Li +1 位作者 Xiaolei Li Lihua Xie 《Journal of Automation and Intelligence》 2023年第2期70-78,共9页
This article studies distributed pose(orientation and position)estimation of leader–follower multi-agent systems over𝜅-layer graphs in 2-D plane.Only the leaders have access to their orientations and position... This article studies distributed pose(orientation and position)estimation of leader–follower multi-agent systems over𝜅-layer graphs in 2-D plane.Only the leaders have access to their orientations and positions,while the followers can measure the relative bearings or(angular and linear)velocities in their unknown local coordinate frames.For the orientation estimation,the local relative bearings are used to obtain the relative orientations among the agents,based on which a distributed orientation estimation algorithm is proposed for each follower to estimate its orientation.For the position estimation,the local relative bearings are used to obtain the position constraints among the agents,and a distributed position estimation algorithm is proposed for each follower to estimate its position by solving its position constraints.Both the orientation and position estimation errors converge to zero asymptotically.A simulation example is given to verify the theoretical results. 展开更多
关键词 Pose estimation distributed algorithm Bearing measurements Multi-agent system Local coordinate frame 2-D plane
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Measured dynamic load distribution within the in situ axlebox bearing of high-speed trains under polygonal wheel–rail excitation
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作者 Yu Hou Xi Wang +4 位作者 Jiaqi Wei Menghua Zhao Wei Zhao Huailong Shi Chengyu Sha 《Railway Engineering Science》 EI 2024年第4期444-460,共17页
The dynamic load distribution within in-service axlebox bearings of high-speed trains is crucial for the fatigue reliability assessment and forward design of axlebox bearings. This paper presents an in situ measuremen... The dynamic load distribution within in-service axlebox bearings of high-speed trains is crucial for the fatigue reliability assessment and forward design of axlebox bearings. This paper presents an in situ measurement of the dynamic load distribution in the four rows of two axlebox bearings on a bogie wheelset of a high-speed train under polygonal wheel–rail excitation. The measurement employed an improved strain-based method to measure the dynamic radial load distribution of roller bearings. The four rows of two axlebox bearings on a wheelset exhibited different ranges of loaded zones and different means of distributed loads. Besides, the mean value and standard deviation of measured roller–raceway contact loads showed non-monotonic variations with the frequency of wheel–rail excitation. The fatigue life of the four bearing rows under polygonal wheel–rail excitation was quantitatively predicted by compiling the measured roller–raceway contact load spectra of the most loaded position and considering the load spectra as input. 展开更多
关键词 High-speed train Axlebox bearing Dynamic load distribution In situ measurement Polygonal wheel–rail excitation
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A distributed measurement method for in-situ soil moisture content by using carbon-fiber heated cable 被引量:14
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作者 Dingfeng Cao Bin Shi +3 位作者 Honghu Zhu Guangqing Wei Shen-En Chen Junfan Yan 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2015年第6期700-707,共8页
Moisture content is a fundamental physical index that quantifies soil property and is closely associatedwith the hydrological, ecological and engineering behaviors of soil. To measure in-situ soil moisturecontents, a ... Moisture content is a fundamental physical index that quantifies soil property and is closely associatedwith the hydrological, ecological and engineering behaviors of soil. To measure in-situ soil moisturecontents, a distributed measurement system for in-situ soil moisture content (SM-DTS) is introduced.The system is based on carbon-fiber heated cable (CFHC) technology that has been developed to enhancethe measuring accuracy of in-situ soil moisture content. Using CFHC technique, a temperature characteristicvalue (Tt) can be defined from temperatureetime curves. A relationship among Tt, soil thermalimpedance coefficient and soil moisture content is then established in laboratory. The feasibility of theSM-DTS technology to provide distributed measurements of in-situ soil moisture content is verifiedthrough field tests. The research reported herein indicates that the proposed SM-DTS is capable ofmeasuring in-situ soil moisture content over long distances and large areas. 展开更多
关键词 In-situ soil moisture content distributed measurement Carbon-fiber heated cable (CFHC) Fiber-optic sensing
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Performance evaluation of two types of heated cables for distributedtemperature sensing-based measurement of soil moisture content 被引量:9
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作者 Dingfeng Cao Bin Shi +3 位作者 Honghu Zhu Kun Zhu Guangqing Wei Kai Gu 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2016年第2期212-217,共6页
Distributed temperature sensing(DTS)using heated cables has been recently developed for distributed monitoring of in-situ soil moisture content.In this method,the thermal and electrical properties of heated cables hav... Distributed temperature sensing(DTS)using heated cables has been recently developed for distributed monitoring of in-situ soil moisture content.In this method,the thermal and electrical properties of heated cables have a significant influence on the measurement accuracy of soil moisture content.In this paper,the performances of two heated cables,i.e.the carbon-fiber heated cable(CFHC)and the metalnet heated cable(MNHC),are studied in the laboratory.Their structures,uniformity in the axial direction,measurement accuracy and suitability are evaluated.The test results indicate that the MNHC has a better uniformity in the axial direction than CFHC.Both CFHC and MNHC have high measurement accuracy.The CFHC is more suitable for short-distance measurement(500 m),while the MNHC can be used for longdistance measurement(>500 m). 展开更多
关键词 Soil moisture content Carbon-fiber heated cable(CFHC) Metal-net heated cable(MNHC) distributed measurement Optical fiber
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On-Line Measurement of the Chemical Oxygen Demand in Wastewater in a Pulp and Paper Mill Using Near Infrared Spectroscopy 被引量:5
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作者 John Dahlbacka Josefina Nystrom +2 位作者 Torgny Mossing Paul Geladi Tom Lillhonga 《Spectral Analysis Review》 2014年第4期19-25,共7页
Although near infrared (NIR) spectroscopy has been evaluated for numerous applications, the number of actual on-line or even on-site industrial applications seems to be very limited. In the present paper, the attempts... Although near infrared (NIR) spectroscopy has been evaluated for numerous applications, the number of actual on-line or even on-site industrial applications seems to be very limited. In the present paper, the attempts to produce online predictions of the chemical oxygen demand (COD) in wastewater from a pulp and paper mill using NIR spectroscopy are described. The task was perceived as very challenging, but with a root mean square error of prediction of 149 mg/l, roughly corresponding to 1/10 of the studied concentration interval, this attempt was deemed as successful. This result was obtained by using partial least squares model regression, interpolated reference values for calibration purposes, and by evenly distributing the calibration data in the concentration space. This work may also represent the first industrial application of online COD measurements in wastewater using NIR spectroscopy. 展开更多
关键词 Chemical Oxygen Demand (COD) Industrial Wastewater Near Infrared Spectroscopy (NIR) Multivariate Calibration on-line measurement
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A Study of Model for Distributed Measurement and Control System 被引量:2
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作者 张劲 钟毅芳 《微计算机信息》 2003年第9期17-20,共4页
This paper is concerned with a method for forming distributed measurement and control system.A three-layer structure model based on network,physical node layer and func-tion node layer is discussed.It is designed on o... This paper is concerned with a method for forming distributed measurement and control system.A three-layer structure model based on network,physical node layer and func-tion node layer is discussed.It is designed on object-oriented software method.The model has a fine application prospect. 展开更多
关键词 分布式测控系统 面向对象 框架模型 软件方法 网络协议
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Distributed sampling measurement method of network traffic in high-speed IPv6 networks
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作者 Pan Qiao Pei Changxing 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2007年第4期835-840,共6页
With the advent of large-scale and high-speed IPv6 network technology, an effective multi-point traffic sampling is becoming a necessity. A distributed multi-point traffic sampling method that provides an accurate and... With the advent of large-scale and high-speed IPv6 network technology, an effective multi-point traffic sampling is becoming a necessity. A distributed multi-point traffic sampling method that provides an accurate and efficient solution to measure IPv6 traffic is proposed. The proposed method is to sample IPv6 traffic based on the analysis of bit randomness of each byte in the packet header. It offers a way to consistently select the same subset of packets at each measurement point, which satisfies the requirement of the distributed multi-point measurement. Finally, using real IPv6 traffic traces, the conclusion that the sampled traffic data have a good uniformity that satisfies the requirement of sampling randomness and can correctly reflect the packet size distribution of full packet trace is proved. 展开更多
关键词 network measurement traffic sampling IPV6 distributed measurement Shannon entropy
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Estimation of spatially distributed processes using mobile sensor networks with missing measurements
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作者 江正仙 崔宝同 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第2期109-115,共7页
This paper investigates the estimation problem for a spatially distributed process described by a partial differential equation with missing measurements.The randomly missing measurements are introduced in order to be... This paper investigates the estimation problem for a spatially distributed process described by a partial differential equation with missing measurements.The randomly missing measurements are introduced in order to better reflect the reality in the sensor network.To improve the estimation performance for the spatially distributed process,a network of sensors which are allowed to move within the spatial domain is used.We aim to design an estimator which is used to approximate the distributed process and the mobile trajectories for sensors such that,for all possible missing measurements,the estimation error system is globally asymptotically stable in the mean square sense.By constructing Lyapunov functionals and using inequality analysis,the guidance scheme of every sensor and the convergence of the estimation error system are obtained.Finally,a numerical example is given to verify the effectiveness of the proposed estimator utilizing the proposed guidance scheme for sensors. 展开更多
关键词 ESTIMATION spatially distributed process mobile sensor network missing measurements
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A METHOD OF ON-LINE MEASUREMENT FOR THE FREQUENCY RESPONSE AND IMPULSE RESPONSE FUNCTIONS OF MULTIVARIATE SYSTEM
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作者 汪凤泉 韩晓林 吴慧新 《Journal of Southeast University(English Edition)》 EI CAS 1993年第1期95-101,共7页
In this paper,a method of multipoint pseudorandom combined excita-tion with the orthogonal reciprocal repeated sequences(ORRS)is presented on thebackground of the on-line identification of multivariate system.The capa... In this paper,a method of multipoint pseudorandom combined excita-tion with the orthogonal reciprocal repeated sequences(ORRS)is presented on thebackground of the on-line identification of multivariate system.The capacity of therestraint to the identification error caused by the non-random D.C.drift of the mul-ti-input excitation with the ORRS in the multivariate system is also discussed.Thevalidity of the method described in this paper is proved by the modelling tests of themulti-plate rotor system. 展开更多
关键词 on-line IDENTIFICATION multi-point EXCITATION ORTHOGONAL reciprocal repeated SEQUENCE VIBRATION measurement
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On-line non-intrusive particle size measurement of pulverised fuel through digital imaging 被引量:3
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作者 Carter Robert M 《仪器仪表学报》 EI CAS CSCD 北大核心 2007年第11期1942-1946,共5页
This paper presents the basic principles of particle size measurement and latest industrial results recorded using an innovative optical instrumentation system designed to measure the size distribution of particles in... This paper presents the basic principles of particle size measurement and latest industrial results recorded using an innovative optical instrumentation system designed to measure the size distribution of particles in a pneumatic suspension.The system is non-intrusive and cost-effective.A low-cost CCD camera is used to capture images of the particulate flow field,which is illuminated by a low-cost pulsed laser sheet generator.The particle size distribution is then determined by processing the particle images through the use of novel processing algorithms.Experimental results obtained in the past on a small scale particle flow test rig have demonstrated that the system is capable of measuring the size distribution of pneumatically conveyed particles with an accuracy of a few percent.For the present paper results obtained when testing the system at a 4 MW industrial test facility are presented.Comparisons are made with both off-line reference data achieved through sieving and on-line laser diffraction data recorded using an intrusive,extractive,Malvern Instruments system.In general there is good agreement between results when considering the characteristics and limitations of the individual methodologies.The novel imaging system shows itself to be rugged,practical and useful under genuine industrial conditions. 展开更多
关键词 粒子 测量方法 数字成像 数码
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On-line Temperature Rise Measurement of Submersible Motors
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作者 王凤昌 刘宝廷 +1 位作者 宋黎明 姜思杰 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 1995年第1期47-49,共3页
A new approach to the on-line temperature rise measurement of submersible pump's motors is presented. A new method of power supply and signed transmission for the measurement device in the pump well is also put fo... A new approach to the on-line temperature rise measurement of submersible pump's motors is presented. A new method of power supply and signed transmission for the measurement device in the pump well is also put forward here. The design and some experimental results are given. 展开更多
关键词 ss: SUBMERSIBLE MOTOR TEMPERATURE RISE on-line measurement
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Design of Distributed Temperature Measurement System for Switchgear
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作者 Qingsong Yang Jianfei Yang +1 位作者 Huaren Wu Long Liu 《Energy and Power Engineering》 2013年第4期958-961,共4页
This paper develops a novel distributed temperature measurement system based on DSP and DS18B20 digital thermometer. The real-time temperature of each node in the switchgear is obtained by several DS18B20s which are c... This paper develops a novel distributed temperature measurement system based on DSP and DS18B20 digital thermometer. The real-time temperature of each node in the switchgear is obtained by several DS18B20s which are connected on the 1-wire bus together. RS-485 master-slave communication protocol is used to centralize monitoring temperatures of several switchgear cabinets. The system also has the function of temperature alarm. The operation of simulation experiment has showed that the system is able to complete monitoring real-time temperatures in high voltage switchgear. 展开更多
关键词 High Voltage SWITCHGEAR distributed Temperature measurement 1-WIRE BUS RS-485 MASTER-SLAVE Communication
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Integrated On-line Instrumentation System of Magnetic Properties Measurement
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作者 D.G.Park, Y.Y.Song. H.Song and J.H.Hong (Korea Atomic Energy Research Institute, Yusong P.O.Box 105, Taejon, 305-600 Korea) C.G.Kim (Department of Physics, Sun Moon Univ., Asan-si, Chungnam, 336840 Korea) 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2000年第2期248-249,共2页
A portable microcomputer-controlled inspection system has been developed for detection of magnetic properties of soft magnetic materials. It incorporates custom designed software for control of the magnetic field duri... A portable microcomputer-controlled inspection system has been developed for detection of magnetic properties of soft magnetic materials. It incorporates custom designed software for control of the magnetic field during operation such as demagnetization, field sweeping, and for data logging and analysis. Results are recorded using a 12-bit analog to digital converter and are then stored on disk. The magnetic hysteresis loop and Barkhausen noise data can be converted into important magnetic parameters: coecivity, remanence, and hysteresis loss, Barkhausen amplitude, and Barkhausen noise energy. This system incorporated with the magnetostriction, and magnetoacoustic emission, is then related with the nondestructive detection of material degradation. 展开更多
关键词 line Integrated on-line Instrumentation System of Magnetic Properties measurement
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A Multi-agent Architecture in CORBA Environment for Distributed Measurement System
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作者 罗小川 《High Technology Letters》 EI CAS 2001年第3期55-59,共5页
The MACE - a Multi agent based distributed measurement architecture in CORBA environment used to develop intelligent distributed measurement system for remote control and monitoring of instruments over network such as... The MACE - a Multi agent based distributed measurement architecture in CORBA environment used to develop intelligent distributed measurement system for remote control and monitoring of instruments over network such as Internet and Ethernet was proposed. The architecture is characterized by interoperability, collaboration and intelligence by means of CORBA and multi agent technologies. The architecture and exemplifies it by a common project was described. 展开更多
关键词 distributed measurement system CORBA Multi agent system Software agent distributed computing
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Wireless Distributed Monitoring Terminal Used for On-Line Application
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作者 Fenggui Wang Lin Zhang +1 位作者 Zhongmin Wang Yanbo Zhang 《Communications and Network》 2013年第3期549-553,共5页
A wireless distributed monitoring terminal was designed with embedded Linux used on the basis of ARM board, and an application program was developed for data collection, processing and transmission. Data were collecte... A wireless distributed monitoring terminal was designed with embedded Linux used on the basis of ARM board, and an application program was developed for data collection, processing and transmission. Data were collected from the surrounding environment and transmitted to a server via WLAN in the form of Extensible Markup Language (XML) stream, so the terminal had good flexibility to be compatible with different sensors, network devices and information systems from multiple manufacturers. 展开更多
关键词 on-line MONITORING distributed MONITORING Extensible MARKUP Language (XML) STREAM WIRELESS TERMINAL
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Research on Collaboration Theory of Distributed Measurement System and Real-Time of Communication Platform
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作者 SHENYan 《Journal of Electronic Science and Technology of China》 2005年第1期95-95,共1页
关键词 distributed measurement system agent technology swarm intellgence Particle Swarm Optimization algorithm Collaboration model Switched Ethernet Real-time Scheduling AEROENGINE
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Measurement methods of particle size distribution in emulsion polymerization 被引量:5
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作者 Shuaifeng Zhang Qinghua Zhang +2 位作者 Jianzhuang Shang Zaisha Mao Chao Yang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2021年第11期1-15,共15页
The particle size distribution of polymer always develops in emulsion polymerization systems,and certain key phenomena/mechanisms as well as properties of the final product are significantly affected by this distribut... The particle size distribution of polymer always develops in emulsion polymerization systems,and certain key phenomena/mechanisms as well as properties of the final product are significantly affected by this distribution.This review mainly focuses on the measurement methods of particle size distribution rather than average particle size during the emulsion polymerization process,including the existing off-line,on-line,and in-line measurement methods.Moreover,the principle,resolution,performance,advantages,and drawbacks of various methods for evaluating particle size distribution are contrasted and illustrated.Besides,several possible development directions or solutions of the in-line measurement technology are explored. 展开更多
关键词 Particle size distribution Emulsion polymerization OFF-LINE on-line IN-LINE
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Simultaneous estimation of aerosol optical constants and size distribution from angular light-scattering measurement signals 被引量:3
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作者 Zhen-Zong He Dong Liang +1 位作者 Jun-Kui Mao Xing-Si Han 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第5期564-572,共9页
The angular light-scattering measurement(ALSM) method combined with an improved artificial bee colony algorithm is introduced to determine aerosol optical constants and aerosol size distribution(ASD) simultaneousl... The angular light-scattering measurement(ALSM) method combined with an improved artificial bee colony algorithm is introduced to determine aerosol optical constants and aerosol size distribution(ASD) simultaneously. Meanwhile, an optimized selection principle of the ALSM signals based on the sensitivity analysis and principle component analysis(PCA)is proposed to improve the accuracy of the retrieval results. The sensitivity analysis of the ALSM signals to the optical constants or characteristic parameters in the ASD is studied first to find the optimized selection region of measurement angles. Then, the PCA is adopted to select the optimized measurement angles within the optimized selection region obtained by sensitivity analysis. The investigation reveals that, compared with random selection measurement angles, the optimized selection measurement angles can provide more useful measurement information to ensure the retrieval accuracy. Finally,the aerosol optical constants and the ASDs are reconstructed simultaneously. The results show that the retrieval accuracy of refractive indices is better than that of absorption indices, while the characteristic parameters in ASDs have similar retrieval accuracy. Moreover, the retrieval accuracy in studying L-N distribution is a little better than that in studying Gamma distribution for the difference of corresponding correlation coefficient matrixes of the ALSM signals. All the results confirm that the proposed technique is an effective and reliable technique in estimating the aerosol optical constants and ASD simultaneously. 展开更多
关键词 angular light-scattering measurement method aerosol optical constants aerosol size distribution inverse radiation problem
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Side abutment pressure distribution by field measurement 被引量:8
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作者 WANG Lian-guo SONG Yang +1 位作者 HE Xing-hua ZHANG Jian 《Journal of China University of Mining and Technology》 EI 2008年第4期527-530,共4页
Given the 7123 working face in the Qidong Coal Mine of the Wanbei Mining Group, nine dynamic roof monitors were installed in the crossheading to measure the amount and velocity of roof convergence in different positio... Given the 7123 working face in the Qidong Coal Mine of the Wanbei Mining Group, nine dynamic roof monitors were installed in the crossheading to measure the amount and velocity of roof convergence in different positions and at different times and three steel bored stress sensors were installed in the return airway to measure rock stress at depth. On the basis of this arrange- ment, the rule of change of the distribution of the side abutment pressure with the advance of the working face and movement of overlying strata was studied. The rule of change and the stability of rock stress at depth were measured. Secondly, the affected area and stability time of the side abutment pressure were also studied. The results show that: 1) During working, the face advanced distance was from 157 m to 99 m, the process was not effected by mining induced pressure. When the distance was 82 m, the posi- tion of peak stress was 5 m away from the coal wall. When the distance was 37 m, the position of peak stress away from the coal wall was about 15 m to 20 m and finally reached a steady state; 2) the time and the range of the peak of side rock pressure obtained from stress sensors were consistent with the results from the dynamic roof monitors; 3) the position of the peak pressure was 25 m away from the coal wall. 展开更多
关键词 field measurement side abutment pressure peak pressure pressure distribution
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