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Articles 57661 - 57690 of 197988

Full-Text Articles in Engineering

Influence Of Water Injection In Burst-Prone Coal Seam On Suction And Sticking During Drilling, Hao Zhiyong, Li Zhiwei, Pan Yishan Jun 2020

Influence Of Water Injection In Burst-Prone Coal Seam On Suction And Sticking During Drilling, Hao Zhiyong, Li Zhiwei, Pan Yishan

Coal Geology & Exploration

When the spiral drill pipe is used to predict and evaluate the dynamic disasters such as rock burst, the drilling dynamic phenomena such as suction and sticking are easy to occur. In order to study the influence of water injection in burst-prone coal seam on suction and sticking, the mechanism of dynamic phenomenon of suction and sticking was analyzed by establishing the mechanical model of drill pipe, pointing out that the stress of coal body and the amount of drilling cuttings are the important factors that affect the occurrence of suction and sticking, deriving the calculation formula of drilling mechanical …

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Managing Off-Grid Power Use For Solar Fueled Residences With Smart Appliances, Prices-To-Devices And Iot, Donnelle L. January Jun 2020

Managing Off-Grid Power Use For Solar Fueled Residences With Smart Appliances, Prices-To-Devices And Iot, Donnelle L. January

USF Tampa Graduate Theses and Dissertations

Electricity availability has a profound impact in day to day life. Activities such as lighting homes, charging cellphones, and running appliances all depend on electricity use. Around 1 billion people around the world do not have access to electricity, and the majority of these people hail from developing countries in remote areas. Moreover, many of these remote areas lack utility grid access due to the infeasible cost of extending the grid to remote communities. To combat this, various projects on microgrids have been implemented in order to distribute power to these off-grid areas. Nanogrids are defined as “a single domain …

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Table Of Contents, The Editors Jun 2020

Table Of Contents, The Editors

Coal Geology & Exploration

No abstract provided.

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Study Of Parallelized Graph Clustering Algorithm Based On Spark, Dongjiang Liu, Jianhui Li Jun 2020

Study Of Parallelized Graph Clustering Algorithm Based On Spark, Dongjiang Liu, Jianhui Li

Journal of System Simulation

Abstract: The parallelized graph clustering algorithm is researched. A new parallelized graph clustering algorithm is proposed based on Spark. As the top operation of Spark occupies a lot of memory space, a new algorithm which is used to substitute the top operation is proposed to reduce the memory consumption. By improving bottom up hierarchical clustering algorithm, the speed of the proposed algorithm is improved. A new data filtering method based on the feature of graph data is proposed. By the method, the running time and memory space comsuption is reduced greatly. The reason of the high efficiency of this filtering …

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A Multi-Strategy Differential Evolution Algorithm Combined With Neighborhood Search, Can Sun, Xinyu Zhou, Mingwen Wang Jun 2020

A Multi-Strategy Differential Evolution Algorithm Combined With Neighborhood Search, Can Sun, Xinyu Zhou, Mingwen Wang

Journal of System Simulation

Abstract: The difficulties of designing a multi-strategy differential evolution (DE) algorithm are how to select the mutation strategies and allocate these strategies. A multi-strategy DE algorithm combined with the neighborhood search operator is proposed. The population is divided into three subpopulations according to the fitness values, and each subpopulation employs a different mutation strategy and parameter settings to complement the search ability, to balance the exploration and exploitation ability of the whole population. The subpopulation with the best fitness values employs the neighborhood search operator to exploit possible benefit information to guide the search. Extensive experiments are carried out on …

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Holiday Highway Traffic Flow Prediction Method Based On Deep Learning, Xiaofeng Ji, Yicheng Ge Jun 2020

Holiday Highway Traffic Flow Prediction Method Based On Deep Learning, Xiaofeng Ji, Yicheng Ge

Journal of System Simulation

Abstract: Accurately predicting highway traffic holiday flow can provide important data for the emergency management of highway. The LSTM-SVR prediction model is established by using the theoretical framework of deep learning. The BP neural network is used to process the sample data, and the data features captured by LSTM are input into the SVR regression layer to realize the traffic flow prediction. Before and after the “Eleventh” Golden Week, the LSTM-SVR model was verified by using the traffic monitoring data of the intermodulation station in Lijiang City and the prediction results were compared with the others. It is found that …

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Additive Manufactured And Laser Enhanced Optical Fiber On Flexible Kapton Substrate, Dianhao Hou Jun 2020

Additive Manufactured And Laser Enhanced Optical Fiber On Flexible Kapton Substrate, Dianhao Hou

USF Tampa Graduate Theses and Dissertations

This thesis mainly focuses on the realization of laser enhancing additive manufactured optical fibers on the flexible substrate based on previous work on the rigid surface, and the exploration of their loss at different bend status by optical transmission test. Optical fibers are successfully fabricated using polymethyl methacrylate by fused deposition modeling technology within Norland Optical Adhesive 1369 which is chosen as the cladding material and micro-dispensed on the Kapton substrate. The Laser cutting technology and scanning electron microscope have been used to enhance and characterize the flatness of two end facets of samples, respectively. The optical adhesive and PMMA …

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Van Der Waals Epitaxy Of Ultrathin Early Transition Metal (Ti & V) (Di)Selenides: Charge And Magnetic Order In The Ultrathin Limit, Manuel Bonilla Lopez Jun 2020

Van Der Waals Epitaxy Of Ultrathin Early Transition Metal (Ti & V) (Di)Selenides: Charge And Magnetic Order In The Ultrathin Limit, Manuel Bonilla Lopez

USF Tampa Graduate Theses and Dissertations

Since the isolation of graphene in 2004, two-dimensional (2D) layered materials, specially the transition metal dichalcogenides (TMDs), have attracted immense interest from theoreticians and experimentalist due to the diversity of properties presented in this family of materials. The main reason for the interest in such materials has been the observation of emergent properties as a consequence of the reduced dimensions, i.e. the monolayer regime. Initially the monolayer regime was obtained via the scotch-tape method. The implementation of exfoliation techniques was successful since layered 2D materials are composed of stacked layers held together by weak van der Walls forces that permits …

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Study On Evacuation Cellular Automaton Model Considering Avoidance Behavior, Yinghua Song, Zhang Yu, Feizhou Huo, Lü Wei, Yaping Ma Jun 2020

Study On Evacuation Cellular Automaton Model Considering Avoidance Behavior, Yinghua Song, Zhang Yu, Feizhou Huo, Lü Wei, Yaping Ma

Journal of System Simulation

Abstract: To study the avoidance behavior in the evacuation process, a cellular automaton model considering avoidance behavior is established. The model divides the evacuees into avoiders and transferees, and reflects the avoidance behavior by changing the selected probability of evacuees. The impact of the avoidance behavior on the efficiency and evacuation process in different personnel ratios and different initial positions is analyzed. The results show that the avoidance behavior can optimize the evacuation sequence, improve the evacuation efficiency and reduce the risk of evacuation process. The evacuation time is significantly reduced when the probability of avoidance exceeds the thread value, …

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Crowd Evacuation Model Based On Improved Pso Algorithm, Changhua Li, Chenggong Bi, Zhijie Li Jun 2020

Crowd Evacuation Model Based On Improved Pso Algorithm, Changhua Li, Chenggong Bi, Zhijie Li

Journal of System Simulation

Abstract: Aiming at the poor local optimization ability and easy premature convergence of the particle swarm optimization (PSO) algorithm in evacuation simulation, a crowd evacuation model based on the improved PSO algorithm is proposed. On the basis of the original model, factors such as the forward driving force, exclusion driving force and panic degree of evacuees are introduced. According to the environmental factors and crowd movement, evacuees' direction is dynamically adjusted, and tends to the ideal exit under the optimal exit selection mechanism. The parametric simulation experiment of evacuation efficiency is carried out for the physical factors such as the …

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A Discrete Krill Herd Algorithm For The No-Wait Flow Shop Scheduling Problem, Changping Liu, Zhenfu Jian, Wenhan Fu Jun 2020

A Discrete Krill Herd Algorithm For The No-Wait Flow Shop Scheduling Problem, Changping Liu, Zhenfu Jian, Wenhan Fu

Journal of System Simulation

Abstract: A discrete krill herd algorithm (DKH) is proposed to solve the no-wait flow shop scheduling problem (NWFSP) with the makespan criterion. Based on the characteristics of the optimization mechanism, the notion of “virtual food” in krill herd algorithm and the influenced crossover rules between krill individuals are defined. The concept and calculation method of the individual distance are redefined to measure the neighborhood range to realize the information exchange. The local search strategies of random swap, inverse and insert operator are employed to enhance the local search ability of DKH, and the multiple initialization strategies are redesigned to promote …

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3d Reconstruction Of Uav Sequence Image Based On Motion Structure Graph, Yuhao Wu, Xuefeng Cao, Jinchao Peng, Lianrui Xu Jun 2020

3d Reconstruction Of Uav Sequence Image Based On Motion Structure Graph, Yuhao Wu, Xuefeng Cao, Jinchao Peng, Lianrui Xu

Journal of System Simulation

Abstract: UAV sequence image has the characteristics of high overlap and strong topological connection. Aiming at the inefficient and unstable in processing the large-scale UAV images of the existing incremental 3D reconstruction algorithm, a 3D reconstruction method based on motion structure graph is proposed. The image matching index is established by using the geolocation information and IMU data to improve the image matching efficiency, and the random motion consistency algorithm is used to calculate the relative motion; motion structure graph is used to represent the "association" between images, and closed-loop detection algorithm is used to eliminate the false edges. Under …

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Modeling And Simulation Of Quadrotor Uav With Vector Thrust Based On Backstepping, Zhou Nan, Wang Liang, Jianliang Ai Jun 2020

Modeling And Simulation Of Quadrotor Uav With Vector Thrust Based On Backstepping, Zhou Nan, Wang Liang, Jianliang Ai

Journal of System Simulation

Abstract: Combined with characteristics of the traditional quadrotor and the quad tilt-wing UAV, a quadrotor UAV with the vector thrust (VTQ) is proposed. This UAV has the ability of vertical take-off and landing and hovering, as well as the high maneuverability of the traditional quad tilt-wing UAV. It has the ability of completing the diversified tasks by being specified the desired yaw angle and pitch angle. Control system adopts the method of the layered design. The upper layer is the position control system, the lower layer is the attitude control system, and the control laws are both designed by the …

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Research On Modeling Technology For Hard Cutting Process, Caixu Yue, Liu Xin, Jiang Nan, Xianli Liu, Genghuang He, Lingxiang Li Jun 2020

Research On Modeling Technology For Hard Cutting Process, Caixu Yue, Liu Xin, Jiang Nan, Xianli Liu, Genghuang He, Lingxiang Li

Journal of System Simulation

Abstract: The hard cutting has the features of the high maching flexibility, economical efficiency and environmental friendliness, and is widely used in automobile industry, bearing industry, hydraulic industry, etc. The simulation modeling not only plays an important role in predicting the performance of the hard machining and optimizing machining parameters, but also better reflects the nature of the machining and provides the theoretical guidance to the actual machining. The simulation modeling methods of the hard cutting at home and abroad are introduced, and the chip formation, cutting force, cutting temperature, tool wear and machined surface quality are summarized, and the …

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Spatiotemporal Saliency Detection Of Infrared Videos Based On Gestalt-Guided Optimization, Wang Xin, Chunyan Zhang, Ning Chen Jun 2020

Spatiotemporal Saliency Detection Of Infrared Videos Based On Gestalt-Guided Optimization, Wang Xin, Chunyan Zhang, Ning Chen

Journal of System Simulation

Abstract: A spatiotemporal saliency detection method based on Gestalt optimization is proposed. A method based on the multi-scale local sparse representation and local contrast measure is proposed to compute the spatial saliency in the infrared videos. A multi-frame symmetric difference approach is adopted to detect the temporal saliency. To get the initial spatiotemporal saliency map, a scheme based on the mutual-consistency is designed to fuse the spatial and temporal saliency maps adaptively. A Gestalt-guided optimization method is designed to calculate the final spatiotemporal saliency map. Experimental results show that the proposed method can effectively detect the spatiotemporal saliency of infrared …

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Virtual-Point-Light Sampling Algorithm Based On Indirect Illumination Clustering Of Visible Scene Region, Chen Sheng, Chunyi Chen, Qiwei Xing, Chaozhi Yang Jun 2020

Virtual-Point-Light Sampling Algorithm Based On Indirect Illumination Clustering Of Visible Scene Region, Chen Sheng, Chunyi Chen, Qiwei Xing, Chaozhi Yang

Journal of System Simulation

Abstract: Focusing on the accuracy of indirect illumination calculation, an improved view-sensitive virtual point light (VPL) sampling method is proposed. The visible shading points are clustered according to the positions and normal vectors. The product of the contribution of VPLs on the representative visible shading points and the number of VPLs belonging to the same class is calculated, and the sum of the products is treated as the estimation of the indirect illumination which constructs the cumulative distribution function (CDF). On the basis of the CDF, the VPLs of calculating the indirect illumination on every visible shading point are selected. …

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Intelligent Evaluation Of Simulation Training For Aerial Ammunition Technical Support, Xu Gang, Zhang Lei, Tian Lei Jun 2020

Intelligent Evaluation Of Simulation Training For Aerial Ammunition Technical Support, Xu Gang, Zhang Lei, Tian Lei

Journal of System Simulation

Abstract: Quantitative evaluation is an important part of the simulation training of the Aviation Ammunition technical support. In order to realize the automatic evaluation of the simulation training, intelligent evaluation technology is introduced, and a prediction model based on Sigmoid regression is proposed. On the basis of analyzing the linear relationship of the sample data of the performance indicators, a subset of the characteristic indicators is selected as the input of the prediction mathematical model. In order to avoid the gradient descent method falling into the local solution problem, the gradient descent + PSO algorithm is presented. After testing the …

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Dynamics Modeling And Simulation Of Gait Rehabilitation Robot Based On Lie Groups And Lie Algebras Theory, Bingjing Guo, Jianhai Han, Xiangpan Li, Yan Lin Jun 2020

Dynamics Modeling And Simulation Of Gait Rehabilitation Robot Based On Lie Groups And Lie Algebras Theory, Bingjing Guo, Jianhai Han, Xiangpan Li, Yan Lin

Journal of System Simulation

Abstract: A pneumatic-driven gait rehabilitation robot based on rigid mechanism and flexible driver is designed. To explore the dynamic characteristics of the human-robot harmony system constructed by patients and the exoskeleton robot, the dynamic models of human, robot and human-robot system in different gait phases are established based on Lie group and Lie algebra theory. The driving and energy characteristics of three rehabilitation training modes of passive, active assistance and resistance are analyzed. The robot joint driven moment and the human active moment are simulated to verify the Lie group and Lie algebraic modeling method and the dynamic model. It …

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Cae Modeling And Fault Simulation For Instantaneous Action Mechanism With High Power And Heavy Load, Teng Lin, Tang Tang, Qiaojie Li, Chen Ming Jun 2020

Cae Modeling And Fault Simulation For Instantaneous Action Mechanism With High Power And Heavy Load, Teng Lin, Tang Tang, Qiaojie Li, Chen Ming

Journal of System Simulation

Abstract: A FEM simulation of a high voltage circuit breaker under actual conditions is proposed to solve the high-frequency vibration and mechanical failure problems caused by the realistic factors such as the clearance and structural elasticity of the breaker. Its operating characteristic under the high power pulse load is analyzed and the influence of the spring stiffness and dimension error on the breaker’s motion characteristics was predicted. On the basis of the dependency of the breaker’s mechanical characteristics on potential faults, critical parameters and design defects are established. The new FEM of the a high-voltage circuit breaker will replace the …

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Augmented Reality Interactive Media System For Ancient Buildings Based On Servomotor, Xingquan Cai, Zhe Yang, He Xin, Chen Chao Jun 2020

Augmented Reality Interactive Media System For Ancient Buildings Based On Servomotor, Xingquan Cai, Zhe Yang, He Xin, Chen Chao

Journal of System Simulation

Abstract: Augmented reality is usually limited to the screen devices, and is difficult to realize the stereoscopic dynamic interaction of multiplayer. A large screen interactive display method based on the servo motor is prsented. The serial communication program to control the scanning reciprocating mode of the servo is designed. By using the edge detection methods and deep normal texture processing, the line draft of the ancient buildings is rendered. By combining the hardware and presentation application modules, the user interaction capabilities and seasonal effects is added to the showcase application modules. The experimental results show that the interactive media system …

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Simulation Optimization Of Initial Fire Evacuation Schemes For Vertical Ship Lift, Chen Shu, Xi Yan, Jianping Wang, Menghan Shang, Li Zhi Jun 2020

Simulation Optimization Of Initial Fire Evacuation Schemes For Vertical Ship Lift, Chen Shu, Xi Yan, Jianping Wang, Menghan Shang, Li Zhi

Journal of System Simulation

Abstract: In order to improve the efficiency of fire evacuation in the initial stage of the vertical ship lift and reduce the evacuation time, the structure and evacuation channel of the vertical ship lift are analyzed to identity the vertical evacuation path. The vertical evacuation time is determined by comparing the evacuation time of stairs and elevator based on the docking rules of cargos. Aiming at the shortest vertical evacuation time the evacuation time of the different docking elevations is simulated to obtain the optimal evacuation plan. The results show that, when the distance between the docking elevation and the …

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Adaptive Differential Crisscross Optimization Algorithm For Dynamic Economic Emission Dispatch Considering Wind Power, Panpan Mei, Lianghong Wu, Hongqiang Zhang, Huiying Wang Jun 2020

Adaptive Differential Crisscross Optimization Algorithm For Dynamic Economic Emission Dispatch Considering Wind Power, Panpan Mei, Lianghong Wu, Hongqiang Zhang, Huiying Wang

Journal of System Simulation

Abstract: Because of the randomness and fluctuation of the wind power, the large scale wind power integration makes the economic emission dispatch of power systems more complicated. By fusing the advantages of the differential evolution algorithm with the parameter self-adaption and crisscross optimization, a hybrid intelligent optimization algorithm called ADE-CSO is proposed to solve the dynamic economic emission dispatch considering wind power integration. A constraint handling technology is introduced to satisfy the feasibility of the power balance and ramp limits. To demonstrate the effectiveness of the proposed algorithm, a typical test case of five generator bus system is conducted and …

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Production Decline Law And Influencing Factors Of High-Rank Coal Cbm Wells, Jia Huimin, Hu Qiujia, Mao Jianwei,, Mao Chonghao, Liu Chunchun, Zhang Qing, Liu Changping Jun 2020

Production Decline Law And Influencing Factors Of High-Rank Coal Cbm Wells, Jia Huimin, Hu Qiujia, Mao Jianwei,, Mao Chonghao, Liu Chunchun, Zhang Qing, Liu Changping

Coal Geology & Exploration

In order to reveal the production decline law of high-rank coal CBM wells, based on the development data of Fanzhuang block in southern Qinshui basin for more than 10 years, this paper studies the decline point, decline type and influencing factors of high-rank coal CBM wells by means of numerical simulation and statistical analysis. The results show that the decline point of the Fanzhuang block is 25% and the average decline point of the single well is 21%. Most wells begin to decline after drainage of 4 years. The decline point of CBM well is determined by matrix permeability and …

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Fracturing Parameters Analysis And Productivity Evaluation Of Vertical Coalbed Methane Wells With Nitrogen Foam, Li Hengle, Cao Yunxing, Zhou Dan, Chai Xuezhou, Liu Tongji, Feng Peiwen, Shi Bin, Tian Lin Jun 2020

Fracturing Parameters Analysis And Productivity Evaluation Of Vertical Coalbed Methane Wells With Nitrogen Foam, Li Hengle, Cao Yunxing, Zhou Dan, Chai Xuezhou, Liu Tongji, Feng Peiwen, Shi Bin, Tian Lin

Coal Geology & Exploration

Fracturing parameters are important parameters that affect the fracturing effect, fracture characteristics and CBM productivity. Through an in-depth understanding of the influence of fracturing parameters on productivity, it is essential to optimize the fracturing process and increase the productivity of CBM wells. Taking 45 nitrogen foam fracturing wells in Lu’an mining area as the research object, the types of fracturing operation curves and their effects on productivity were studied. The relationship between fracturing fluid dosage and productivity was discussed. The differences in productivity of nitrogen foam wells and hydraulic fracturing wells was compared and analyzed. The results show that: Nitrogen …

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Hydrogeochemical Evolution Of No.15 Coal Seam And Limestone K2 In Southern Qinshui Basin, Li Zhongcheng, Wu Jianguang, Wang Jianzhong, Wu Xiang, Lu Guojun Jun 2020

Hydrogeochemical Evolution Of No.15 Coal Seam And Limestone K2 In Southern Qinshui Basin, Li Zhongcheng, Wu Jianguang, Wang Jianzhong, Wu Xiang, Lu Guojun

Coal Geology & Exploration

Based on the water test data of No.15 coal roof K2 limestone and No.15 coalbed methane well in the southern Qinshui basin, the characteristics, types and the genetic mechanism of water chemical composition were systematically studied by statistical and comparative methods. The evolution model was built to systematically describe the various reactions and effects of limestone and coalbed water in the recharge zone, runoff zone and detention zone. The results show that the K2 limestone water and the No.15 coal seam water will undergo ion exchange, mixing and CO2 action. The K2 limestone water is mainly …

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Effect Of Acidification On The Microstructure And Physical Properties Of Shale, Chen Liuyu, Li Xijian, Shen Zhonghui, Xu Shiqing, Ma Shengxiang, Yin Xin Jun 2020

Effect Of Acidification On The Microstructure And Physical Properties Of Shale, Chen Liuyu, Li Xijian, Shen Zhonghui, Xu Shiqing, Ma Shengxiang, Yin Xin

Coal Geology & Exploration

As the main shale gas reservoir in Guizhou, it is proved that Longmaxi Formation has good shale gas accumulation conditions and resource development potential. In order to reveal the response law of acidification on the micropore structure and physical properties of Longmaxi Formation shale in Guizhou, the difference in physical properties of shale microstructures before and after acidification, such as pore volume, porosity, specific surface area and pore size distribution was quantitatively characterized by X-ray diffraction(XRD) analysis, mercury intrusion measurement, low-temperature nitrogen adsorption and nuclear magnetic resonance(NMR) experiment. The structural characteristics of the shale pores before and after acidification were …

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Water Environment Comprehensive Forewarning For Waterlogged Area In Huainan Based On Weber-Fechner Law, Pei Wenming, Zhang Hui, Ju Changhua, Yao Suping, Ren Yongle, Ma Mengxiao, Qiu Kuanbiao Jun 2020

Water Environment Comprehensive Forewarning For Waterlogged Area In Huainan Based On Weber-Fechner Law, Pei Wenming, Zhang Hui, Ju Changhua, Yao Suping, Ren Yongle, Ma Mengxiao, Qiu Kuanbiao

Coal Geology & Exploration

In area with high groundwater level in the east of China, long-time underground coal mining results in a large subsidence water area on the surface. The risk of water environment pollution in subsidence waters is increasing gradually with the influence of human activities. According to Weber-Fisher law, this paper took Panji waterlogged area of Huainan as the research object, selected the water quality evaluation indexes closely related to the water environment of the waterlogged area, analyzed the water environmental conditions of the waterlogged area in different periods, and quantitatively reflected the time and the area of the water environment quality …

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Performance Test And Proportioning Optimization Of Loess-Based Grouting Materials In Coal Mining Subsidence Area Of Northern Shaanxi, Cao Xiaoyi, Wang Yutao, Liu Xiaoping, Cao Zubao, Wu Boqiang Jun 2020

Performance Test And Proportioning Optimization Of Loess-Based Grouting Materials In Coal Mining Subsidence Area Of Northern Shaanxi, Cao Xiaoyi, Wang Yutao, Liu Xiaoping, Cao Zubao, Wu Boqiang

Coal Geology & Exploration

Grouting is the main treatment method of mining subsidence area, and the grouting materials have great influence on the grouting effect and cost. Taking the grout mix composed of loess and cement used in northern Shaanxi as the research object, the viscosity, the gelation time, the stone rate and 28 d uniaxial unconfined compressive strength of loess grout were studied by single factor and orthogonal tests. The influencing factors and changing rule of each index were analyzed. Meanwhile, the GA-BPNN prediction model of loess-based grout was established, and the multi-objective global optimization was carried out through GA. The grout ratio …

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Exploration And Quantitative Evaluation Of Overburden Strata “Three Zones” In Deep Strip Mining, Liu Zhen, Wang Yutao, Liu Xiaoping, Wang Xiaodong Jun 2020

Exploration And Quantitative Evaluation Of Overburden Strata “Three Zones” In Deep Strip Mining, Liu Zhen, Wang Yutao, Liu Xiaoping, Wang Xiaodong

Coal Geology & Exploration

In order to study the height of overburden fractures in deep strip mining, engineering geological drilling, borehole television and coalfield well logging have been applied to detect and analyze the overburden fractures in a coal mine in Jining coalfield. The results indicate that, under the strip mining with gentle dip(6°), deep depth(538 m) and 1:2 mining-retention ratio(mining -50 m and remaining -100 m), the “three zones” develop prominently, presenting “wavy” destruction in space, and the goaf has no obvious cavity. The height of caving zone is 8.45 m which is 3.0 times of the mining height, and the fault zone …

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Stacking Angle Of Slurry-Aeolian Sand Dual-Phase Medium Filling Material, Bai Zhongrong Jun 2020

Stacking Angle Of Slurry-Aeolian Sand Dual-Phase Medium Filling Material, Bai Zhongrong

Coal Geology & Exploration

Stacking angle is an important parameter to describe the spatial accumulation pattern of filling material in the goaf. It has important guiding significance for determining the drilling distance, optimizing the slurry configuration and adjusting the grouting process parameters. In order to grasp the variation law of stacking angle of slurry-aeolian sand dual-phase medium filling material, using self-flow stacking model experiment of tailings and rheological properties experiment, the mixing ratio of aeolian sand was taken as a variable to determine the slurry accumulation parameters and rheological parameters on different conditions of sand ratio. Based on this, Sofra & Boger formula was …

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