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International Journal of mining Science and Technology 2017年第5期27卷 883-887页

作者： Liu Chao Li Shugang Cheng Cheng Xue Junhua School of safety Science and Engineering Xi’an University of Science and TechniqueXi’an 710054China State Key Laboratory of Deep Coal mining&Environment protection Huainan 710054China

In order to effectively monitor the concealed fault activation process in excavation activities, based on the actual condition of a working face containing faults with high outburst danger in Xin Zhuangzi mine in Huainan, China, we carried out all-side tracking and monitoring on the fault activation process and development trend in excavation activities by establishing a microseismic monitoring system. The results show that excavation activities have a rather great influence on the fault activation. With the working face approaching the fault, the fault activation builds up and the outburst danger increases; when the excavation activities finishes, the fault activation tends to be stable. The number of microseismic events are corresponding to the intensity of fault activation, and the distribution rules of microseismic events can effectively determine the fault occurrence in the mine. Microseismic monitoring technique is accurate in terms of detecting geologic tectonic activities, such as fault activations lying ahead during excavation activities. By utilizing this technique, we can determine outburst danger in excavation activities in time and accordingly take effective countermeasures to prevent and reduce the occurrence of outburst accidents.

关键词： Excavation roadway Fault Microseismic monitoring technique Coal and gas outburst Activation characteristics

Reliability Analysis of a Switched Reluctance Starter/Generator

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protection and Control of Modern Power Systems 2024年第1期9卷 112-121页

作者： Hao Chen Fan Yang Lijun Xu Qiwei Lu Xiqiang Chang Xing Wang Lijiang Dong Yi Wen Jiang Chen Gang Miao Jianmin Hu Guanjun Wang Wei Li Xiaohua Bao School of Electrical Engineering China University of Mining and TechnologyXuzhou 221116China Xinjiang Institute of Engineering Urumqi 830000China International Joint Research Center of Central and Eastern European Countries on New Energy Electric Vehicle Technology and Equipment Xuzhou 221008China International Cooperation Joint Laboratory of New Energy Power Generation and Electric Vehicles of Jiangsu Province Colleges and Universities Xuzhou 221008China School of Information and Electrical Engineering China University of Mining and TechnologyXuzhouChina China University of mining and Technology(Beijing) BeijingChina State Grid Xingjiang Electric Power Co. Ltd.UrumqiXinjiangChina China University of mining and Technology XuzhouChina State Grid Xinjiang Company Limited Electric Power Research Institute UrumqiXinjiangChina Xinjiang Fukang Pumped Storage Power Company Limited UrumqiXinjiangChina State Grid Urumqi Electric Power Supply Company UrumqiXinjiangChina Wuxi Inspection and Testing Certification Research Institute WuxiJiangsuChina Anhui Wannan Electric Machine Co. Ltd.WannanAnhuiChina Hefei University of Technology in Electrical and Automation Engineering

In this paper,the combined k-out-of-n:G model and reliability block diagram model is used to analyze the reliability of a switched reluctance starter/generator ***,the different operational modes of a switched reluctance motor starter/generator are analyzed,and the fault states of the system are briefly *** the fault criteria of the system in different operational states are put ***,a relia-bility block diagram model is established to calculate the system-level reliability,and the k-out-of-n:G model is adopted to analyze the reliability of each part of the switched reluctance starter/generator *** verify effectiveness,the first-order Markov model is also used to analyze the reliability of each part of the switched reluc-tance starter/generator *** the compu-tational complexity and accuracy of the system,the k-out-of-n:G model is more suitable for system component level reliability ***,a 6/4 switched reluctance motor is used as the simulated and experimental platform *** final results verify the effectiveness of the reliability analysis model.

关键词： system switched generator

Creep behaviour and constitutive model of coal filled with gas

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International Journal of mining Science and Technology 2017年第5期27卷 847-851页

作者： Li Xiangchun Yang Chunli Ren Ting Nie Baisheng Zhao Caihong Liu Shuiwen Jiang Tao School of Resource and safety Engineering China University of Mining & Technology Occupational Hazards Control Technology Center Beijing Municipal Institute of Labour Protection Faculty of Engineering and Information Sciences University of Wollongong

Coal exhibits different creep behaviours when filled with different amounts of gas. Creep tests of coal filled with 0 and 0.5 MPa gas were performed, and strain under different axial stress was *** three creep constitutive models which were analysed using the method fitting experimental data for determining which creep model can reflect the creep process of the test best. The results show that the deformation of coal filled with 0.5 MPa gas is more higher than that of coal filled with 0 MPa gas under the same axial stress. Gas plays a positive effect on the deformation of coal process and will accelerate creep process. And gas will reduce coal intensity and change coal creep *** with Nishihara Model and Extensional Nishihara Model, Burgers Model can reflect the three stages of creep process of coal filled with gas better. The research results can contribute to reveal coal and gas outburst mechanism.

关键词： Coal Gas Creep Constitutive model

Structural Controls and Predictive Mapping of Tin, Niobium and Tantalum Mineralization Associated with the Mayo Darlé Stanniferous Granitoids;Contributions of Geostatistics

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Journal of Geoscience and Environment protection 2024年第1期12卷 180-210页

作者： Bah-Yero Liman Ngounouno Ismaïla Mbowou Gbambié Isaac Bertrand Alpha Baster Kenfack Fokem André William Boroh Amadou Diguim Kepnamou Department of Earth Sciences Faculty of Science University of Ngaoundéré Ngaoundéré Cameroon Department of mining Geology School of Geology and Mining and Engineering University of Ngaoundéré Meiganga Cameroon Department of Earth Sciences Faculty of Science University of Garoua Garoua Cameroon

The aim of this study of the spatial dispersion of tin, niobium and tantalum mineralization associated with the Mayo Darlé granitoids was to produce prospecting guides through predictive maps of Sn, Nb and Ta in the region. It was based on a database (in appendix) obtained after analysis of rock samples (greisens and quartz veins) collected in the field, using a portable X-ray fluorescence (XRF) spectrometer. Two approaches were used: 1) structural studies in the field using the directions of veins and fractures 2) the use of variographic maps, an essential element in geostatistics for determining directional anisotropies. A joint synthesis of the modelling results shows that tin, tantalum and niobium mineralization at Mayo Darlé is concentrated along strike intervals N315E to N320E, with mineralization also occurring along strike N35E for high-grade Sn, medium-grade Ta and low-grade Nb. In short, mineral concentrations disperse progressively in space: positively from east to west for tantalum and niobium, and inversely for tin.

关键词： Mayo Darlé Tin Niobium Tantalum Geostatistics Mapping

Towards hydrometeorological thresholds of reservoir-induced landslide from subsurface strain observations

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Science China(Technological Sciences) 2024年第6期67卷 1907-1922页

作者： YE Xiao ZHU HongHu WANG Jia ZHENG WanJi ZHANG Wei SCHENATO Luca PASUTO Alessandro CATANI Filippo School of Earth Sciences and Engineering Nanjing UniversityNanjing210023China Department of Geosciences University of PadovaPadova35131Italy School of Geosciences and Info-Physics Central South UniversityChangsha410083China Department of Information Engineering University of PadovaPadova35131Italy National Research Council-Research Institute for Geo-Hydrological protection(CNR-IRPI) Padova35127Italy

Synergistic multi-factor early warning of large-scale landslides is a crucial component of geohazard prevention and mitigation efforts in reservoir *** forecasting and early warning based on surface displacements have been widely ***,the lack of direct subsurface real-time observations limits our ability to predict critical hydrometeorological conditions that trigger landslide *** this paper,we leverage subsurface strain data measured by high-resolution fiber optic sensing nerves that were installed in a giant reservoir landslide in the Three Gorges Reservoir(TGR)region,China,spanning a whole hydrologic year since February *** spatiotemporal strain profile has preliminarily identified the slip zones and potential drivers,indicating that high-intensity short-duration rainstorms controlled the landslide kinematics from an observation *** the time lag effect,we reexamined and quantified potential controls of accelerated movements using a data-driven approach,which reveals immediate response of landslide deformation to extreme rainfall with a zero-day *** identify critical hydrometeorological rules in accelerated movements,accounting for the dual effect of rainfall and reservoir water level variations,we thus construct a landslide prediction model that relies upon the boosting decision tree(BDT)algorithm using a dataset comprising daily rainfall,rainfall intensity,reservoir water level,water level fluctuations,and slip zone strain time *** results indicate that landslide acceleration is most likely to occur under the conditions of mid-low water levels(i.e.,57.9 mm and rainfall intensity>24.4 mm/h).Moreover,this prediction model allows us to update hydrometeorological thresholds by incorporating the latest monitoring *** on the shoulder of this landslide case,our study informs a practical and reliable path

关键词： slow-moving landslide fiber-optic monitoring subsurface strain hydrometeorological threshold extreme weather

Crossing point temperature of coal

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mining Science and Technology 2011年第2期21卷 255-260页

作者： Qi xuyao Deming Wang James A. Milke Xiaoxing Zhong State Key Laboratory of Coal Resources and Safe mining Faculty of Safety Engineering China University of Mining ＆ Technology Xuzhou 221008 China Department of Fire protection Enguneering University of Maryland College Park MD20742 USA

A further understanding of the self-heating of coal was obtained by investigating the crossing point temperature（CPT） of different ranks of *** tests were carried out using a self-designed experimental system for coal self-heating.50 g（±0.01 g） of coal particles ranging from 0.18 mm to 0.38 mm in size were put into a pure copper reaction vessel attached to the center of a temperature programmed *** temperature program increased the temperature at a rate of 0.8℃/*** air was permitted to flow into the coal reaction vessel at different *** surrounding temperature and the coal temperature were monitored by a temperature *** results indicate that CPT is affected by coal rank,moisture,sulfur, and the experimental *** ranked coals show higher CPT values.A high moisture content causes a delay phenomenon during the self-heating of the *** at 40℃decreases the effects of *** reactivity of sulfur components in the coal is low under dry and low-temperature conditions. These components form a film that covers the coal surface and slightly inhibits the self-heating of the coal. The flow rate of dry air,and the heating rate of the surroundings,also affect the self-heating of the *** most appropriate experimental conditions for coal samples of a given weight and particle size were determined through contrastive *** on this analysis we propose that CPTs be determined under the same,or nearly the same conditions,for evaluation of the spontaneous combustion of coal.

关键词： Coal Spontaneous combustion Crossing point temperature Moisture Sulfur Coal rank

Research on Iron Loss of Switched Reluctance Starter/Generator for Energy Storage

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protection and Control of Modern Power Systems 2024年第4期9卷 147-159页

作者： Hao Chen Xing Wang Yongqiang Liu Vuong Dang Quoc Wenju Yan Muhammad Saqib Antonino Musolino Guanjun Wang Yong Qi Ali Asghar Memon Alexandros G.Paspatis the Shenzhen Research Institute China University of Mining and TechnologyShenzhen 515100China the School of Electrical Engineering China University of Mining and TechnologyXuzhou 221116China Xinjiang Institute of Engineering Urumqi 830000China the International Joint Research Center of Central and Eastern European Countries on New Energy EV Technology and Equipment Xuzhou 221008China the International Cooperation Joint Laboratory of New Energy Power Generation and EVs of Jiangsu Province Colleges and Universities Xuzhou 221008China the Xuzhou Key Laboratory of New Energy EV Technology and Equipment Xuzhou 221008China the the School of Electrical Engineering China University of Mining and Tech-nologyXuzhou 221116China the Laboratory of High Performance Electric Machines(HiPems) Hanoi VN 10000Viet Nam the University of Engineering and Technology Lahore 54890Pakistan the Department of Energy Pisa Uni-versity of PisaPisa IT 56126Italy the Wuxi Inspection and Testing Certification Research Institute Wuxi 214000China the Nanjing University of Science&Tech-nology Nanjing 210094China the Mehran University of Engi-neering&Technology Jamshoro PK 76062Sindh the National Technical University of Athens Zografou GR 15780Attica

In order to better realize the energy recovery and storage of hybrid EVs(HEVs),a switched reluctance starter/generator(SRS/G)with both starting and power generation functions is investigated in this ***,the iron loss of SRS/G is mainly studied to reduce the motor loss and improve the power generation ***,the energy storage of hybrid EVs can be effectively ***,a magnetic flux density(MFD)waveforms solution method is proposed to solve the difficulty in calculating the iron loss of the SRS/*** with the commonly used finite element method,the proposed solution method has the advantages of simple,fast and small computational ***,considering the different operating conditions of SRS/G,the iron loss models for both the time-domain and frequency-domain are *** addition,the calculation formula of the variable coefficient Bertotti three-term loss separation is *** the hysteresis loss coefficient,the Steinmetz coefficient and the stray loss coefficient are respectively fitted by the Fourier fitting *** method is also applied to solve the iron loss of SRS/***,through an experimental verification,it is indicated that the development of proposed method has high accuracy.

关键词： Switched reluctance starter/generator energy storage iron loss finite element method magnetic flux density(MFD)

Creep behavior and permeability evolution of coal pillar dam for underground water reservoir

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International Journal of Coal Science & Technology 2023年第1期10卷 136-141页

作者： Yulong Chen Xianjie Hao Dongjie Xue Zhe Li Xiaoran Ma State Key Laboratory of Water Resource protection andUtilization in Coal mining BeijingChina China University of mining and Technology BeijingBeijingChina

Using goof as water storage space plays a vital role in the ecological environment and economic development of arid mining areas,while the rock strength and the stability of coal pillars in underground water reservoirs are closely related to creep *** this work,triaxial creep-seepage tests were conducted for coal samples to develop new insights into the creep behavior and permeability *** results showed that the creep deformation and permeability evolution of coal samples exhibit three stages,namely,the compaction hardening stage before the stress threshold,volumetric compaction stage,and volumetric dilatancy *** coal permeability decreases first and then increases with the creep strain and it is well correlated with the variation of volumetric strain.

关键词： Coal Creep Permeability Volumetric strain

Simultaneous Waveform Inverse Modelling for Litho-Fluid Prediction in an Old Marginal, “Agbbo”Field, Onshore Niger Delta, Nigeria

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Journal of Geoscience and Environment protection 2024年第5期12卷 40-59页

作者： Charles Chibueze Ugbor Peter Ogobi Odong Chukwuemeka Austine Okonkwo Department of Geology University of Nigeria Nsukka Nigeria Department of Geology and mining Enugu State University of Science and Technology Enugu Nigeria

Simultaneous waveform inversion was used to predict lithofacies and fluid type across the field. Very often, characterizing reservoirs in terms of lithology and fluid type using conventional methods is replete with uncertainties, especially in marginal fields. An approach is employed in this study that integrated rock physics and waveform inverse modelling for lithology and fluid-type characterization to appropriately identify potential hydrocarbon saturated zones and their corresponding lithology. Seismic and well-log data were analyzed using Hampson Russel software. The method adopted includes lithofacies and fluid content analysis using rock physics parameters and seismic simultaneous inverse modelling. Rock physics analysis identified 2 broad reservoirs namely: HDZ1 and HDZ2 reservoirs. Results from the inverse modelling showed that low values of acoustic impedance from 19,743 to 20,487 (ft/s)(g/cc) reflect hydrocarbon-bearing reservoirs while medium to high values shows brine and shale respectively, with brine zone ranging from 20,487 to 22,531 (ft/s)(g/cc) and shale above 22,531 (ft/s)(g/cc). Two lithofacies were identified from inversion analysis of Vp/Vs and Mu-Rho, namely: sand and shale with VpVs 1.95 values respectively. Mu-Rho > 12.29 (GPa)(g/cc) and <12.29 (GPa) (g/cc) represent sand and shale respectively. From 3D volume, it was observed that a high accumulation of hydrocarbon was observed to be saturated at the north to the eastern part of the field forming a meandering channel. Sands were mainly distributed around the northeastern to the southwestern part of the field, that tends to be away from Well 029. This was also validated by the volume of rigidity modulus (Mu-Rho) showing high values indicating sands fall within the northeastern part of the field.

关键词： Simultaneous Waveform Inversion Lithofacies Fluid Type Rock Physics Hydrocarbon Acoustic Impedance Mu-Rho Reservoir

Numerical simulation of gas flow process in mining-induced crack network

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International Journal of mining Science and Technology 2012年第6期22卷 793-799页

作者： Zhou Hongwei Liu Jinfeng Xue Dongjie Yi Haiyang Xue Junhua State Key Laboratory of Coal Resources and Safe mining China University of Mining & Technology State Key Laboratory of Deep Coal mining and Environmental protection Huainan Mining Group Corporation

The exploitation of coal bed methane or coal gas is one of the most effective solutions of the problem of coal gas hazard.A better understanding of gas flow in mining-induced cracks plays an important role in comprehensive development and utilization of coal gas as well as prevention of coal gas *** paper presents a case study of gas flow in mining-induced crack network regarding the situation of low permeability of coal seam.A two-dimensional physical model is constructed on the basis of geological background of mining face No.1122(1) in coal seam No.11-2,Zhangji Coal Mine,Huainan mining Group *** mining-induced stress and cracks in overburden rocks are obtained by simulating an extraction in physical *** evolution of mining-induced cracks in the process of advancing of coal mining face is characterized and three typical crack networks are taken from digital photos by means of image ***,the numerical software named COMSOL Multiphysics is employed to simulate the process of gas flow in three representative crack *** of gas pressure at various times in mining-induced crack networks are plotted,suggesting a shape and dimension of gas accumulation area.

关键词： Gas flow Gas pressure Physical modeling mining-induced cracks COMSOL