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2019

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Articles 31 - 60 of 2185

Full-Text Articles in Engineering

The Study Of Dynamic Modes Of Converters With Movable Electromagnetic Screens And Distributed Parameters, S.F. Amirov, О.Т. Boltayev Dec 2019

The Study Of Dynamic Modes Of Converters With Movable Electromagnetic Screens And Distributed Parameters, S.F. Amirov, О.Т. Boltayev

Chemical Technology, Control and Management

In article for research of dynamic characteristics of the created Converter with mobile electromagnetic screens and with the distributed parameters, the parametric block diagram is made. Based on the parametric block diagram, the analytical equation of the output voltage in the operator form is compiled for the dynamic mode. In order to study the dynamic properties of the transducer with moving electromagnetic screens and distributed parameters, the influence of input values on the reaction of the transducer is considered. On the basis of the revealed expressions the nonlinearities of the transient process are considered.

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A Study On Electrical Energy Measuring Device In Installation Place, Anatoliy Plakhtiev, Gayratjon Gaziev Dec 2019

A Study On Electrical Energy Measuring Device In Installation Place, Anatoliy Plakhtiev, Gayratjon Gaziev

Chemical Technology, Control and Management

An analysis of the metrological support of electric energy metering devices has been carried out, which allows us to note a number of shortcomings, which include the insufficiency and imperfection of normative and technical documentation on electric energy metering and control, operation and verification of existing measuring instruments, poor equipment of enterprises and territorial bodies of Uzstandart Agency with high-performance calibration installations, the absence of portable compact installations for checking meters at the place of use, braztsovyh higher accuracy of measuring (standards). Information is provided on the developed device that allows structurally minimizing the error in current conversion and using …

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Modeling Of Multicomponent Rectification Under Uncertainty, Nodirbek Rustambekovich Yusupbekov, Djalol Patxiddinovich Mukhitdinov, Yorkin Bakhodirovich Kadirov Dec 2019

Modeling Of Multicomponent Rectification Under Uncertainty, Nodirbek Rustambekovich Yusupbekov, Djalol Patxiddinovich Mukhitdinov, Yorkin Bakhodirovich Kadirov

Chemical Technology, Control and Management

This paper presents a complete computer model for an industrial distillation column, which considers the input, output and model (nonlinearity and high-frequency dynamics of the process) uncertainties. The proposed model has a great advantage of covering the entire working range of the distillation column. This model can be used as a main tool for the analysis and synthesis of distillation process control systems.

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Algorithms For Regular Synthesis Of Adaptive Systems Management Of Technological Objects Based On The Concepts Of Identification Approach, Husan Zakirovich Igamberdiev, Jasur Usmonovich Sevinov Dec 2019

Algorithms For Regular Synthesis Of Adaptive Systems Management Of Technological Objects Based On The Concepts Of Identification Approach, Husan Zakirovich Igamberdiev, Jasur Usmonovich Sevinov

Chemical Technology, Control and Management

Stable algorithms of adaptive control, estimation of controller parameters, synthesis of adaptive control of dynamic objects by the criterion of minimum dispersion, and synthesis of suboptimal adaptive-local control of dynamic objects based on predictive models are presented. Algorithms for the stable identification of dynamic control objects based on regularization and pseudoinversion methods based on a singular decomposition are presented. Based on the use of approximations in the form of a finite sum of Gaussian distributions, recurrent identification algorithms have been developed using multiple models and adapting their parameters. Stable algorithms are proposed for identifying the parameters of an object and …

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Sustainable Algorithms For Generalized Estimation Of Dynamic Control Objects, Yulduz Muhtarhodjaeva Abdurakhmanova Dec 2019

Sustainable Algorithms For Generalized Estimation Of Dynamic Control Objects, Yulduz Muhtarhodjaeva Abdurakhmanova

Chemical Technology, Control and Management

The problems of separate and generalized assessment of the state and parameters of controlled objects under conditions of varying degrees of a priori uncertainty are considered. Stable algorithms for the generalized estimation of the state and parameters based on the quasilinearization method and the formal model of motion under conditions of statistical uncertainty, as well as the correction of the results of the generalized estimation, are presented. It is shown that the considered regularized generalized coordinate and parametric estimation algorithms make it possible to recover with sufficient accuracy the extended state vector of a dynamical system. The above algorithms make …

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Optimization Of Image Processing Using Characteristics And Peculiarities Of Pollen Grains, I.I. Jumanov, O.I. Djumanov, R.A. Safarov Dec 2019

Optimization Of Image Processing Using Characteristics And Peculiarities Of Pollen Grains, I.I. Jumanov, O.I. Djumanov, R.A. Safarov

Chemical Technology, Control and Management

The problem is formulated and methods for processing images, in particular pollen grains, based on the mechanisms for extracting statistical, dynamic, texture and specific characteristics, as well as geometric features of micro-objects, are developed. Methods are proposed for assessing the accuracy of processing information on the characteristics of points, point and non-linear verification of the contour of the input and reference images, highlighting, segmenting, contrasting, interpolating. The mechanisms of extracting frequency, cytoplasm, reticules, spores, textures, morphology, and geometric features of pollen grain images are studied. A set of programs for processing microobject images in C ++ language in the CUDA …

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Electrochemical Properties Of Sulfur In Different Carbon Support Materials, Bo Zhang, Jia Liu, Xiao-Chen Liu, De-Jun Li Dec 2019

Electrochemical Properties Of Sulfur In Different Carbon Support Materials, Bo Zhang, Jia Liu, Xiao-Chen Liu, De-Jun Li

Journal of Electrochemistry

In order to investigate the effect of carbon structure on electrochemical performance of sulfur/carbon composite in lithium-sulfur battery, in this paper, sublimation sulfur was incorporated into three types of carbon materials, namely, graphene, carbon black and porous carbon. The three sulfur/carbon composites were characterized by scanning electron microscopy (SEM), Brunauer-Emmett-Teller (BET), and X-ray diffraction (XRD) techniques, and their electrochemical performances were also studied. The results showed that the sulfur/porous carbon composite offered an initial discharge capacity of 1623.2 mA·h·g-1 and remained 845 mA·h·g-1 after 100 cycles. Compared with graphene and carbon black, the mesopores and micropores in porous …

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Electrochemical Behaviors Of Azopurine On Gold Electrodes, Ming-Xue Li, Hang Shi, Jia Liu, Meng Zhang, Jian-Zhang Zhou, De-Yin Wu, Zhong-Qun Tian Dec 2019

Electrochemical Behaviors Of Azopurine On Gold Electrodes, Ming-Xue Li, Hang Shi, Jia Liu, Meng Zhang, Jian-Zhang Zhou, De-Yin Wu, Zhong-Qun Tian

Journal of Electrochemistry

In this paper, we studied the electrochemical behaviors of azopurine on polished gold electrodes with cyclic voltammetry (CV). On the basis of analyzing scan rate and peak current, it was supposed that the redox process belonged to a reversible process controlled by adsorption in 0.2 mol·L-1 PBS (pH = 4.0 ~ 10.0) solutions. The potentials of redox peaks moved more negatively with increasing pH value. This proved that the H+ proton has participcted in the electrochemical reaction. The further data analysis and the calculation of surface adsorption excess demonstrated that the reaction was a two-proton and two-electron process. …

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Morphology Controlled Preparations And Electrochemical Properties Of Znco2O4 Electrode Materials For Supercapacitors, Yue-Shen Zhou, Meng Li, Shuang Wu, Zhao-Lei Li, Yan-Min Gao Dec 2019

Morphology Controlled Preparations And Electrochemical Properties Of Znco2O4 Electrode Materials For Supercapacitors, Yue-Shen Zhou, Meng Li, Shuang Wu, Zhao-Lei Li, Yan-Min Gao

Journal of Electrochemistry

In this work, hydrothermal reaction and high temperature were used to grow ZnCo2O4 active materials on Ni foam. The crystal stuctures and surface morphlogies of four samples were investigated by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM). The electrochemical performances were characterized by cyclic voltammetry (CV)、galvanostatic charge/discharge (GCD) testing and electrochemical impedance spectroscopy (EIS) on an electrochemical station. It can be seen that active materials tended to form denser stuctures with an increasing amount of NH4F in the solution system and four different morphologies of ZnCo2O …

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Impact Of Organizational Culture And Perceived Process Safety In The Uae Oil And Gas Industry, Mohamed Ali Al Mazrouei Mr., Khalizani Khalid Dr., Ross Davidson Dr., Salam Abdallah Dr. Dec 2019

Impact Of Organizational Culture And Perceived Process Safety In The Uae Oil And Gas Industry, Mohamed Ali Al Mazrouei Mr., Khalizani Khalid Dr., Ross Davidson Dr., Salam Abdallah Dr.

The Qualitative Report

In the last few decades, there had been a lot of accidents in the oil and gas industry throughout the world. This article reports a qualitative study of 30 employees employed in the United Arab Emirates (UAE) oil and gas industry. Health, Safety, and Environment (HSE) culture is a concept which was studied in many researches. However, this research is set to examine how certain behaviors affect the safety performance in UAE’s oil and gas industry. Four core themes that were drawn from the interviewee discussions of how safety culture, leadership safety behaviors, supervisory safety behaviors, and employee training on …

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Comprehensive Evaluation Technology And Application Of Grouting Reinforcement Effect For Broken Coal And Rock Mass, Wang Xiaolei, Ji Zhigang, Luo Wenqiang Dec 2019

Comprehensive Evaluation Technology And Application Of Grouting Reinforcement Effect For Broken Coal And Rock Mass, Wang Xiaolei, Ji Zhigang, Luo Wenqiang

Coal Geology & Exploration

Grouting reinforcement of broken coal and rock mass plays an important role in controlling the stability of surrounding rocks, and the grouting effect detection is an important link to ensure the grouting engineering to meet the requirements. The evaluation index was quantitatively analyzed by slurry filling rate method, mechanical parameter method, segmented water injection method, geological radar method, drilling television method and core inspection method. The comprehensive evaluation form of grouting effect was put forward, and the application research was carried out. The results show:The rate of filling slurry and coring was more than 90%; After grouting, the compressive strength …

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Microscopic Fabric Characteristics Of Typical Red Soft Rock In Badong Formation Under Uniaxial Compression Test, Xiao Zunqun, Wang Xin, Tang Dongsang, Dong Qiongying, Jiang Yinan, Yang Kai, Cao Tongtong, Deng Zhen Dec 2019

Microscopic Fabric Characteristics Of Typical Red Soft Rock In Badong Formation Under Uniaxial Compression Test, Xiao Zunqun, Wang Xin, Tang Dongsang, Dong Qiongying, Jiang Yinan, Yang Kai, Cao Tongtong, Deng Zhen

Coal Geology & Exploration

Red silty mudstone and argillaceous siltstone are the representatives of special rock and soil in Badong Formation, are easy to disintegrate when encountering water. According to the uniaxial compression test of rock samples, a numerical model of medium and soft rock uniaxial compression test was established based on PFC2D program. With the characteristics of stress-strain curve, subsection quantitative parameter calibration method was used to calibrate the microscopic parameters of soft rock samples. The adjustment method and the ratio of tangential bond strength(σc/τc) control specimen under uniaxial compression failure mode. The uniaxial compression test of silty …

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Combined Cbm Production Behavior And Development Strategy Of Multiple Coal Seams In Zhijin Block, Guo Tao, Gao Xiaokang, Meng Guixi, Xiao Cui Dec 2019

Combined Cbm Production Behavior And Development Strategy Of Multiple Coal Seams In Zhijin Block, Guo Tao, Gao Xiaokang, Meng Guixi, Xiao Cui

Coal Geology & Exploration

Aiming at the problems that the CBM layers are numerous and thin, it is difficult to develop it effectively in south China, on the basis of the actual production data of CBM wells in Zhijin block, the production characteristics and the influencing factors of gas production of the directional wells for co-extraction of different seams and the horizontal wells for thin seams were analyzed, and corresponding suggestions for CBM development were put forward. The analysis indicated that the gas production of co-extraction of different seams was quite different, was influenced by the liquid-supplying capacity of formation, the height of desorbing …

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Analysis Of Suitable Development Technology Of Cbm(Gas) In Guizhou, Xu Xiaoqian, Meng Yingfang, Duan Zhengpeng, Li Guohong, Li Qingsong Dec 2019

Analysis Of Suitable Development Technology Of Cbm(Gas) In Guizhou, Xu Xiaoqian, Meng Yingfang, Duan Zhengpeng, Li Guohong, Li Qingsong

Coal Geology & Exploration

In recent years, technical bottlenecks have been encountered in the practice of CBM exploration and development in Guizhou Province, selecting suitable development technology is one of the key issues. Based on the background that CBM exists in thin coal seams and geological structures are complicated in Guizhou, combined with successful development and utilization of CBM, the CBM development and utilization technology suitable for complex geological conditions in Guizhou was put forward. Air drilling is recommended for drilling in Guizhou, according to different distance of thin seams, such as optical casing composite fracturing and salvageable bridge plug fracturing can be used. …

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Evaluation Of Coalbed Methane Drainage Effect For Multi-Target Seams In Jincheng Region, Yang Jianchao, Li Guihong, Liu Yuhui, Li Guofu, Wang Chaoshuai, Sun Tianyu Dec 2019

Evaluation Of Coalbed Methane Drainage Effect For Multi-Target Seams In Jincheng Region, Yang Jianchao, Li Guihong, Liu Yuhui, Li Guofu, Wang Chaoshuai, Sun Tianyu

Coal Geology & Exploration

The study of the multi-target seams drainage effect on coalbed methane wells has great value, including coal safe mining, underground gas control, determination of development technical indicators, single well production, rational division of development layer, efficient development of coalbed methane, and development of medium and long-term coalbed methane development planning. Taking Chengzhuang mine of Jincheng as an example, the sampling data of the extraction effect in the middle and late stages of development are compared with the original gas content of the adjacent wells to evaluate the extraction effect, and the main control factors affecting the drainage effect are analyzed …

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Key Technology Of Drilling In-Seam Directional Borehole Of 3 000 M In Underground Coal Mine, Shi Zhijun, Dong Shuning, Yang Junzhe, Xu Chao, Hao Shijun, Li Quanxin, Chen Dianfu, Yao Ke, Liu Jianlin, Tian Dongzhuang Dec 2019

Key Technology Of Drilling In-Seam Directional Borehole Of 3 000 M In Underground Coal Mine, Shi Zhijun, Dong Shuning, Yang Junzhe, Xu Chao, Hao Shijun, Li Quanxin, Chen Dianfu, Yao Ke, Liu Jianlin, Tian Dongzhuang

Coal Geology & Exploration

The pre-mining gas governance mode in Baode coal mine requires that long directional borehole of more than 3 000 m can be drilled along coal seam. In view of the existing technology and equipment, there are technical problems in the construction of ultra-long directional borehole, such as the difficulty of sliding drilling, the large hydraulic pressure consumption in inlet waterway, the limited transmission distance of wireline MWD signal, and incapability of flushing liquid recycle. The technology of friction reduction in sliding drilling based on the hydraulic thrust of DHM and the torsion penetration of the ultra-long drilling tool, the technology …

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Extension Model Of Fracturing Cracks Of Translayer Horizontal Well In Roof Of Soft Coal Reservoir, Wang Zhirong, Hu Kai, Yang Jie, Chen Lingxia Dec 2019

Extension Model Of Fracturing Cracks Of Translayer Horizontal Well In Roof Of Soft Coal Reservoir, Wang Zhirong, Hu Kai, Yang Jie, Chen Lingxia

Coal Geology & Exploration

In order to study the propagation rules of hydraulic fracturing crack formed by a horizontal well in roof to coal seam, taking the Permian-Carboniferous coal field in North China as an example, through the classical theory of fracture mechanics, damage mechanics and fluid mechanics, combined with field actual data, the modeling and verification of the space-time evolution law of the crack propagation distance and fracturing time were carried out. Firstly, considering the additional stress of perforation, the characteristics of primary fracture and the permeability characteristics of rock formation, the calculation formula of cracking pressure of vertical hydraulic fracture caused by …

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Technology Feasibility Of Gas Drainage With Comb-Shaped Long Borehole In Floor Instead Of Translayer Borehole, Li Hong, Liu Mingju, Hao Guangsheng, Deng Qigen, Dong Yanjun Dec 2019

Technology Feasibility Of Gas Drainage With Comb-Shaped Long Borehole In Floor Instead Of Translayer Borehole, Li Hong, Liu Mingju, Hao Guangsheng, Deng Qigen, Dong Yanjun

Coal Geology & Exploration

Drainage technology of translayer borehole in floor roadway and directional long hole are the most important gas control measures in high gas and outburst-prone mining face at present. The coal seam in Zhaozhuang mine has the characteristics of being soft and low gas permeability. It is difficult to drill and form holes in a coal seam. For gas control, the major method is to drill a translayer borehole to eliminate gas outburst, supplemented by in-seam gas drainage boreholes. However, there are shortcomings such as large engineering volume, long construction period and high cost of drilling in floor rock roadway. The …

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An Improved Method For Characterizing Coal Metamorphism By Xrd, Wang Chao, Zhao Younan, Wang Zhenwei, Lu Zhaolin Dec 2019

An Improved Method For Characterizing Coal Metamorphism By Xrd, Wang Chao, Zhao Younan, Wang Zhenwei, Lu Zhaolin

Coal Geology & Exploration

At present, the X-ray measurement method of coal metamorphism has the problem that the γ band is not well divided, the δ peak information is not used, and the background of the bottom is unreasonable. The X-ray diffraction pattern of coal with different metamorphosed degrees is compared and studied. It is proposed to correct the metamorphic coefficient formula by using the information of the slope of the 002 peak, the extended half-height width and the δ peak without deducting the so-called background information. The calculation of the XRD patterns of coal samples with different degrees of metamorphism is verified. The …

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Table Of Contents, The Editors Dec 2019

Table Of Contents, The Editors

Coal Geology & Exploration

No abstract provided.

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Effect Of False Boundary Of Microscopic Image On Automatic Identification Of Maceral Group, Song Xiaozhong Dec 2019

Effect Of False Boundary Of Microscopic Image On Automatic Identification Of Maceral Group, Song Xiaozhong

Coal Geology & Exploration

In automatic detection of coal petrology by image analysis technology, it is found that the boundary of various components in the microscopic image of coal petrology demonstrates a "rim" of gray transition zone, and the pixel of this rim cannot reflect the true gray level of the components on both sides. In order to analyze its influence on the identification and detection of macerals, the characteristics and causes of the false boundary between various adjacent components were studied with analysis of microscopic images collected from a large number of coal samples in China. Generally, the false boundary is ring-shaped or …

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Effects Of Iron-Nickel Ion Combination On Methane Produced By Lignite Fermentation, Xia Daping, Huang Song, Zhang Huaiwen Dec 2019

Effects Of Iron-Nickel Ion Combination On Methane Produced By Lignite Fermentation, Xia Daping, Huang Song, Zhang Huaiwen

Coal Geology & Exploration

In order to study the mechanism of the influence of exogenous optimal iron-nickel ions combination on the gas production process of fermentation, taking Daliuta lignite as an example, experiments were carried out with different contents of iron-nickel ions and the optimal concentration of single ions was elected. The optimal combination concentration of iron-nickel ions were determined by combined design of quadratic regression and common rotation. The fermentation broth of experiment group and blank group(not to added any ions), the coal sample of before and after experiment were analyzed by gas chromatography, X-ray diffraction, Fourier transform infrared spectroscopy, etc. The results …

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Origin And Geochemical Characteristics Of Coalbed Methane In Abandoned Coal Mines, Panzhuang Block, Southern Qinshui Basin, Liu Chao, Feng Guorui, Zeng Fangui Dec 2019

Origin And Geochemical Characteristics Of Coalbed Methane In Abandoned Coal Mines, Panzhuang Block, Southern Qinshui Basin, Liu Chao, Feng Guorui, Zeng Fangui

Coal Geology & Exploration

In order to analyze the carbon and oxygen composition and origin of the coal seam gas(CSG) in abandoned mines, Panzhuang block, south of Qinshui basin, in this paper, the coalbed methane and produced water samples were collected. The results show that the CSG of abandoned mines is dominated by CH4, the average is 91.99%, with minor amounts of N2(6.73%) and CO2(1.26%). The δ13C values of CH4 range from -31.36‰ to -33.53‰, with an average of -32.25‰, the hydrogen isotope(δD) value is between -182.76‰ and -193.20‰, and the average value …

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Mine Water Inrush Rescue Model Based On Optimized Spfa Algorithm, Cai Mingjie, Zhu Xi’An, Liu Demin, Wang Zhangang Dec 2019

Mine Water Inrush Rescue Model Based On Optimized Spfa Algorithm, Cai Mingjie, Zhu Xi’An, Liu Demin, Wang Zhangang

Coal Geology & Exploration

Due to the occurrence of coal mine water inrush accidents, it is easy to cause major personnel and property losses. In order to improve the emergency rescue capability of mine water inrush disasters and reduce the water inrush hazard, a mine water inrush rescue route model was proposed. The undirected map and the adjacency list were used to describe and store the mine roadway network. According to the calculation ratio of the height of the water level and the height of underground personnel in roadway, the safety coefficient of the roadway was calculated, and then the equivalent length of the …

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Drainage Technology And Test Of Stratified Pressure Control With Four-Channels Of Cbm Well In Double Coal Seams, Pang Tao, Jiang Zaibing, Li Bingang, Du Xinfeng Dec 2019

Drainage Technology And Test Of Stratified Pressure Control With Four-Channels Of Cbm Well In Double Coal Seams, Pang Tao, Jiang Zaibing, Li Bingang, Du Xinfeng

Coal Geology & Exploration

Aiming at the problems of mutual interference between layers and serious damage in reservoirs in the production process of double-coal CBM wells, a four-channel stratified pressure control drainage technology was proposed, in the process of drainage, two coal seams were controlled in different pressure systems to achieve the purpose of stratified production and CBM well drainage device with four-channel packer, monitoring equipment, multi-channel tubing centralizer, roller sucker rod centralizer and auxiliary communication tube for double coal seams was developed. Field application test shows that the four-channel packer can achieve the isolation effect according to the needs, so that the two …

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Optimization Study On Correlation Method Of Multiple Coal Seams, Shu Jiansheng, Ma Liang, Jia Lilong Dec 2019

Optimization Study On Correlation Method Of Multiple Coal Seams, Shu Jiansheng, Ma Liang, Jia Lilong

Coal Geology & Exploration

At present, the development trend of coal mining in China is transferring from the east to the western regions. The Yan'an Formation coal bearing measures middle Jurassic is the most widely distributed in the west, it is of the continental sedimentary environment, which has the characteristics of big change of lithofacies, multiple coal seams, unstable coal seams and less marker, there are difficulties in coal seam correlation, such as lack of basis and multi-solution phenomenon. Based on the wide application of high precision seismic exploration and digital logging technology, the fine correlation of terrestrial multi-coal seams was carried out by …

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Simulation Of Seepage Water Inrush Mechanism And Strength Controlling Factors Of Collapse Column, Huo Bingjie, Xie Zhenhua, Fan Zhanglei, Jing Xuedong Dec 2019

Simulation Of Seepage Water Inrush Mechanism And Strength Controlling Factors Of Collapse Column, Huo Bingjie, Xie Zhenhua, Fan Zhanglei, Jing Xuedong

Coal Geology & Exploration

In order to study the mechanism and main control factors of seepage water inrush in roadway affected by collapse columns, Darcy, Brinkman and N-S equations were used to describe the linkage system of flow field in aquifer, collapse column and water inrush roadway. Variables such as different parameters and different boundaries were selected to analyze the main factors influencing the seepage water inrush intensity of collapse columns. The results show that under the conditions of constant pressure and flow, the increase of aquifer permeability will lead to the increase of flow velocity in an area where the aquifer meets the …

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Particle Swarm Optimization-Based Bionic Principle For Solving Hydrodynamic Dispersion Coefficient In Jiang'an Campus, Mei Jie, Li Guangwei, Xia Chengcheng, Liu Yaping, Liu Wen, He Xinyue Dec 2019

Particle Swarm Optimization-Based Bionic Principle For Solving Hydrodynamic Dispersion Coefficient In Jiang'an Campus, Mei Jie, Li Guangwei, Xia Chengcheng, Liu Yaping, Liu Wen, He Xinyue

Coal Geology & Exploration

Hydrodynamic dispersion coefficient is an important parameter in the study of solute transport in groundwater. In order to understand the transport law of pollutants in groundwater, the particle swarm optimization(PSO) algorithm based on bionic principle is used to solve the hydrodynamic dispersion coefficient of phreatic aquifer under natural flow field in the dispersion test site of Jiang'an Campus of Sichuan University. Compared with the least-square method and the standard curve comparison method, the results show that the results of the standard curve method are subject to subjective influence, and the errors are relatively large. The results of least square method …

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Surface Subsidence Law Caused By Fully Mechanized Caving Mining Under Railway, Deng Niandong, Yao Ting, Shang Hui, Liu Donghai Dec 2019

Surface Subsidence Law Caused By Fully Mechanized Caving Mining Under Railway, Deng Niandong, Yao Ting, Shang Hui, Liu Donghai

Coal Geology & Exploration

In order to ensure the safe running of the special railway for Guozhuang coal mine, the law of surface movement and deformation in goaf of the coal mine was studied on the basis of the analysis of the actual observation data, the monitoring scheme and control measures of railway under dynamic coal mining conditions were put forward in accordance with that. The results show that the surface movement and deformation are intense, the subsidence value is large, but the subsidence velocity is relatively small on account of fully mechanized caving; Surface subsidence coefficient, the main impact tangent tanβ, …

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Deformation Characteristics And Support Timing Of Deep High Stress Roadway, Geng Weile, Dong Ziwen, Guo Shengli, Pi Zikun Dec 2019

Deformation Characteristics And Support Timing Of Deep High Stress Roadway, Geng Weile, Dong Ziwen, Guo Shengli, Pi Zikun

Coal Geology & Exploration

The rock occurrence environment and structural characteristics determine its strength criteria, and affects the mechanical and deformation characteristics of surrounding rock. This paper relies on the deep replacement project of a mine in Yunnan, based on the rock strength criteria, and analyzes the mechanics and deformation characteristics of surrounding rock and the reasonable secondary support time of roadway to decrease the influence of the roadway support effect because of the obvious rheological properties present under high ground stress. The results showed that the min-average simulated deviations mf was generalized H-B criterion which was aimed at the sum of deviation absolute …

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