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Articles 9691 - 9720 of 302419

Full-Text Articles in Physical Sciences and Mathematics

Nano-Optics: Light, Matter, And Single-Molecule Imaging, Nathan Lindquist Oct 2023

Nano-Optics: Light, Matter, And Single-Molecule Imaging, Nathan Lindquist

Day of Scholarship

Light and matter interact in fascinating ways at the nano-scale, allowing scientists to image, probe, analyze, or manipulate single molecules. This interdisciplinary field has opened the doors to a vast array of insights and applications, including single-molecule sensors, advanced photonic devices, and novel forms of microscopy. This poster summarizes work done at Bethel over the past few years in the areas of nano-imaging, nano-sensing, and nano-manipulation.

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Creation And Development Of A Next Generation Simulation Model For Spacecraft Charging, Brian P. Beecken Oct 2023

Creation And Development Of A Next Generation Simulation Model For Spacecraft Charging, Brian P. Beecken

Day of Scholarship

Spacecraft, particularly satellites, endure the bombardment of high-energy electrons. These electrons charge up the insulators on the spacecraft. Eventually, the charge commonaly can exceed 100,000 volts. The result is an electrostatic discharge which will potentially cripple the spacecraft. A computer simulation model has been developed that will predict if and when the discharge will occur.

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A New Algorithm For Determining Energy And Charge Deposition In Spacecraft Insulators, Brian P. Beecken Oct 2023

A New Algorithm For Determining Energy And Charge Deposition In Spacecraft Insulators, Brian P. Beecken

Day of Scholarship

Space if filled with highly energetic electrons, many of which originate from the sun. All earth satellites must have insulators. Unfortunately, the insulators absorb both the electrons and the energy that they are carrying. Once sufficient charge accumulates, it is released in a sudden and destructive pulse which can destroy the onboard electronics and solar panel. The depth of penetration of the electrons in the insulators varies with incident energy, flux, and material. Determining the deposition profiles is key to understanding and mitigating the threat to satellites.

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Computational Chemistry At Bethel, Rollin King Oct 2023

Computational Chemistry At Bethel, Rollin King

Day of Scholarship

In the 21st century, computational methods play a significant role in all areas of chemistry, ranging from small-molecule spectroscopy to drug design. Research in computational chemistry is multidisciplinary, involving the application of physics, math, and computer science to address questions and challenges in chemistry. This poster will survey the field, highlight the outstanding work of Bethel students, and present a couple of ongoing projects.

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Modeling And Estimation Of A Continuous Flexible Structure Using The Theory Of Functional Connections, Riccardo Bevilacqua Oct 2023

Modeling And Estimation Of A Continuous Flexible Structure Using The Theory Of Functional Connections, Riccardo Bevilacqua

Math Department Colloquium Series

This talk presents a novel method for modeling and estimating the dynamics of a continuous structure based on a limited number of noisy measurements. The goal is reached using a Kalman filter in synergy with the recently developed mathematical framework known as the Theory of Functional Connections (TFC). The TFC allows to derive a functional expression capable of representing the entire space of the functions that satisfy a given set of linear and, in some cases, nonlinear constraints. The proposed approach exploits the possibilities offered by the TFC to derive an approximated dynamical model for the flexible system using the …

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Postsynthetic Modification Of The Nonanuclear Node In A Zirconium Metal−Organic Framework For Photocatalytic Oxidation Of Hydrocarbons, Rebecca Shu Hui Khoo, Christian Fiankor, Sizhuo Yang, Wenhui Hu, Chongqing Yang, Jingzhi Lu, Martha D. Morton, Xu Zhang, Yi Liu, Jier Huang, Jian Zhang Oct 2023

Postsynthetic Modification Of The Nonanuclear Node In A Zirconium Metal−Organic Framework For Photocatalytic Oxidation Of Hydrocarbons, Rebecca Shu Hui Khoo, Christian Fiankor, Sizhuo Yang, Wenhui Hu, Chongqing Yang, Jingzhi Lu, Martha D. Morton, Xu Zhang, Yi Liu, Jier Huang, Jian Zhang

Chemistry Department: Faculty Publications

Heterogeneous catalysis plays an indispensable role in chemical production and energy conversion. Incorporation of transition metals into metal oxides and zeolites is a common strategy to fine-tune the activity and selectivity of the resulting solid catalysts, as either the active center or promotor. Studying the underlying mechanism is however challenging. Decorating the metal-oxo clusters with transition metals in metal−organic frameworks (MOFs) via postsynthetic modification offers a rational approach to construct well-defined structural models for better understanding of the reaction mechanism. Therefore, it is important to expand the materials scope beyond the currently widely studied zirconium MOFs consisting of Zr6 …

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When Communities Face Drinking Water Crises, Bottled Water Is A 'Temporary' Solution That Often Lasts Years--And Worsens Inequality, Daniel Jaffee Oct 2023

When Communities Face Drinking Water Crises, Bottled Water Is A 'Temporary' Solution That Often Lasts Years--And Worsens Inequality, Daniel Jaffee

Sociology Faculty Publications and Presentations

As a sociologist, I study the social and environmental effects of the rapid growth of bottled-water consumption in the U.S. and beyond, and how it is linked to distrust of public tap water. In my new book, “Unbottled,” one chapter examines how these dynamics played out in Flint. As its example shows, communities can end up relying on bottled water – often at great expense – for years after a crisis.

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Understanding The Nature Of Pulsars And Characterizing Propagation Effects Using Pulsar Timing, Pratik Kumar Oct 2023

Understanding The Nature Of Pulsars And Characterizing Propagation Effects Using Pulsar Timing, Pratik Kumar

Physics & Astronomy ETDs

Pulsars are highly magnetized stellar remnants, among the densest known objects, and primarily produce radio emission in the form of lighthouse beams sweeping across the line of sight as a regular train of pulses. Apart from providing tests for matter in high-density regimes, general relativity, and plasma emission; perhaps the most notable characteristic is their applicability as precise astronomical clocks to measure various effects. Pulsar Timing Arrays (PTAs) are galactic scale detectors analogous to ground-based detectors of Gravitational Waves (GWs) like LIGO, with the aim of detecting low-frequency nano-Hz GWs from coalescing binary supermassive black holes. PTAs consist of a …

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Water Inrush Mechanism Of Coal Mine Shaft Fracture Under Fluid-Solid Coupling, Xue Weipei, Shen Lei, Yao Zhishu, Cheng Hua, Rong Chuanxin Oct 2023

Water Inrush Mechanism Of Coal Mine Shaft Fracture Under Fluid-Solid Coupling, Xue Weipei, Shen Lei, Yao Zhishu, Cheng Hua, Rong Chuanxin

Coal Geology & Exploration

The occurrence of coal mine shaft fractures and water inrush accidents is alarmingly frequent, endangering the lives of underground personnel and compromising mine safety. To comprehend the influence of confined groundwater in the process of shaft fracture and the formation mechanism of water inrush channels, a model test was devised using similarity theory and coupled fluid-solid numerical simulation technology. The findings reveal that direct contact between the shaft lining and pressurized water hinders the development of load-bearing and deformation capacities. This is specifically evidenced by the premature appearance of the yield point, a reduction in peak strength and strain, and …

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Manipulator Trajectory Planning Method Of Anchor Drilling Robot, Lei Mengyu, Zhang Xuhui, Yang Wenjuan, Dong Zheng, Wan Jicheng, Zhang Chao, Du Yuyang Oct 2023

Manipulator Trajectory Planning Method Of Anchor Drilling Robot, Lei Mengyu, Zhang Xuhui, Yang Wenjuan, Dong Zheng, Wan Jicheng, Zhang Chao, Du Yuyang

Coal Geology & Exploration

In order to improve the support efficiency of coal mine roadway and the automation intelligence of heading face, an anchor drilling robot integrating the cantilever roadheader and the six-degree-of-freedom manipulator was designed, and studied on the anchor drilling sequence planning strategy and the drilling boom trajectory planning method. Firstly, the kinematics model of the manipulator structure was established based on the improved DH method. On this basis, the forward and inverse kinematics solutions were analyzed, and the spatial position and the corresponding joint variable values of the drilling rig were calculated. Secondly, the manipulator space was analyzed based on Monte …

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Table Of Contents, The Editors Oct 2023

Table Of Contents, The Editors

Coal Geology & Exploration

No abstract provided.

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Zoned Prediction Of Water Inflow After Dewatering Of Working Face Based On Waterrichness Zoning Of Aquifer, Yang Lei, Lei Fangchao, Hou Enke, Lu Bo, Feng Dong, Zhao Kaixing Oct 2023

Zoned Prediction Of Water Inflow After Dewatering Of Working Face Based On Waterrichness Zoning Of Aquifer, Yang Lei, Lei Fangchao, Hou Enke, Lu Bo, Feng Dong, Zhao Kaixing

Coal Geology & Exploration

As the weathered bedrock and burned rock aquifers seriously threaten the production safety of mines in the Jurassic coalfield of northern Shaanxi Province, accurate prediction of their waterrichness and water inflow at the working face is of great significance for water control in mines. Aiming at the weathered bedrock and burned rock aquifers with close hydraulic connection, the area where working face 15217 of Shaanxi Hongliulin Coal Mine is located was taken as the study area. Meanwhile, the aquifer thickness, lithological combination index, index of rock burning and weathering degree and core recovery was taken as the evaluation indexes. The …

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Research Progress Of Rotary Steerable System And Its Control Methods, Li Wei, Mou Lei, Zhou Xiancheng, Tan Xianhui, Fu Quan Oct 2023

Research Progress Of Rotary Steerable System And Its Control Methods, Li Wei, Mou Lei, Zhou Xiancheng, Tan Xianhui, Fu Quan

Coal Geology & Exploration

Rotary steerable system is a shining pearl in directional drilling technology and an important technical means to realize the low-cost and efficient development of oil and gas resources. First of all, the basic structure of the rotary steerable system was introduced. According to the different steering modes and bias effects, the rotary steerable system is divided into five categories: static push-the-bit type, dynamic push-the-bit type, static pointing type, dynamic point-the-bit type and mixed type, for which the steering principle was analyzed one by one. Secondly, according to the research and application of rotary steerable system technology at home and abroad, …

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Numerical Simulations And Wavefield Analysis Of In-Seam Wave Advance Detection In Viscoelastic Media, He Dixiu, Ji Guangzhong, Jiao Wenjie, Zhang Yawei, Yu Kun Oct 2023

Numerical Simulations And Wavefield Analysis Of In-Seam Wave Advance Detection In Viscoelastic Media, He Dixiu, Ji Guangzhong, Jiao Wenjie, Zhang Yawei, Yu Kun

Coal Geology & Exploration

In-seam waves are commonly applied to the advance detection of hidden faults in front of mining faces. However, coal seams, which have viscoelasticity actually, imposing absorptive and attenuation effects on in-seam waves. To investigate the wave field characteristics and propagation patterns of in-seam waves in viscoelastic coal seam media, this study built a three-dimensional geological model of coal measures with faults based on Kelvin-Voigt’s first-order velocity-stress equation. Using this equation, three-dimensional finite-difference numerical simulation was carried out. The results indicate that (1) for reflected in-seam waves in viscoelastic media, which exhibit high energy attenuation, their propagation and attenuation characteristics are …

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2023 Celebration Of Scholarship, Creativity, And Engagement, Todd Bruns, Diane Highland Oct 2023

2023 Celebration Of Scholarship, Creativity, And Engagement, Todd Bruns, Diane Highland

Programs

Annually, Eastern Illinois University honors faculty achievements in the areas of research, creativity, and engagement. This year, the list of faculty accomplishments is again truly impressive, reflective of an engaged faculty committed to excellence and the ongoing pursuit and creation of knowledge. A number of these accomplishments occurred in collaboration with our students, who serve as co-authors, research assistants and partners in bringing these activities to fruition. Indeed, in some cases these professional ambitions transpired over the course of many years, and are a testament to persistence and tenacity--ensuring that these works extend to a broader community of scholars that …

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Gas Expansion Energy Of Coals With Different Metamorphic Degrees: Evolutionary Characteristics And Their Implications For The Outburst Prediction, Liu Gaofeng, Li Baolin, Zhang Zhen, Liu Huan, Guan Wenbo, Si Nian Oct 2023

Gas Expansion Energy Of Coals With Different Metamorphic Degrees: Evolutionary Characteristics And Their Implications For The Outburst Prediction, Liu Gaofeng, Li Baolin, Zhang Zhen, Liu Huan, Guan Wenbo, Si Nian

Coal Geology & Exploration

To achieve an elevated accuracy in the prediction of coal and gas outbursts, this study conducted mercury injection capillary pressure (MICP) tests and isotherm adsorption experiments on selected six coal samples with different metamorphic degrees. Furthermore, it calculated the gas expansion energy of coals and analyzed the evolutionary characteristics of the gas expansion energy of coals with different metamorphic degrees, as well as their relationships with the prediction indices of coal and gas outbursts. The results of this study are as follows: (1) The differences in the pore structures and adsorptivity of coals with different metamorphic degrees led to different …

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An Improved Automated Testing Model For Maceral Groups In Coals Based On Deeplabv3+, Hu Jinwei, Xi Zhenghao, Xu Guozhong, Li Zhongfeng, Liu Xiang Oct 2023

An Improved Automated Testing Model For Maceral Groups In Coals Based On Deeplabv3+, Hu Jinwei, Xi Zhenghao, Xu Guozhong, Li Zhongfeng, Liu Xiang

Coal Geology & Exploration

The identification of maceral groups in coals plays a critical role in analyzing the chemical properties of coals. However, manual identification is laborious and requires high expertise. Existing computer-assisted identification methods, mostly adopting deep learning-based semantic segmentation models, fail to accurately identify maceral groups in coals due to complex compositions of microscopic coal images and the presence of transitional components. Therefore, this study proposed an improved DeeplabV3+ semantic segmentation model integrating the Swin Transformer backbone network and the SkNet. First, to deal with the challenge of feature extraction caused by the intertwined maceral groups and the presence of transitional components …

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A New Physics-Informed Method For The Fracability Evaluation Of Shale Oil Reservoirs, Li Yuwei, Li Zijian, Shao Lifei, Tian Fuchun, Tang Jizhou Oct 2023

A New Physics-Informed Method For The Fracability Evaluation Of Shale Oil Reservoirs, Li Yuwei, Li Zijian, Shao Lifei, Tian Fuchun, Tang Jizhou

Coal Geology & Exploration

The accurate evaluation of reservoir fracability is an essential prerequisite for the fracturing design and post-fracturing productivity evaluation of reservoirs. Rock mechanical parameters have been applied to the fracability evaluation of shales presently, exhibiting great field application performance. Accordingly, it is crucial to obtain accurate rock mechanical parameters. This study developed a physics-informed neural network (PINN) model. Driven by data and physical information, the PINN model can accurately predict rock mechanical parameters using only a small amount of data. To verify its performance, the PINN model was compared with the artificial neural network, random forest, and XGBoost models. The comparison …

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Prediction Of Rockburst Intensity Grade Based On Convolutional Neural Network, Li Kangnan, Wu Yaqin, Du Feng, Zhang Xiang, Wang Yiqiao Oct 2023

Prediction Of Rockburst Intensity Grade Based On Convolutional Neural Network, Li Kangnan, Wu Yaqin, Du Feng, Zhang Xiang, Wang Yiqiao

Coal Geology & Exploration

Rockburst is one of the urgent problems to be addressed in the process of deep resource extraction. In order to predict the rockburst disasters safely and efficiently, a rockburst intensity grade prediction model (MICE-CNN) based on the Multiple Imputation by Chained Equations (MICE) and Convolutional Neural Network (CNN) was proposed. Specifically, a predictive indicator system was established based on the main influencing factors and the acquisition conditions of rockburst. A total of 120 sets of raw data from rockburst cases were collected, with the outliers processed by pauta criterion. Then, the missing data were interpolated with the four interpolation models …

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Breakdown Of The Drift-Diffusion Model For Transverse Spin Transport In A Disordered Pt Film, Kirill D. Belashchenko, Giovanni G. Baez Flores, Wuzhang Fang, Alexey Kovalev, Mark Van Schilfgaarde, Paul M. Haney, Mark D. Stiles Oct 2023

Breakdown Of The Drift-Diffusion Model For Transverse Spin Transport In A Disordered Pt Film, Kirill D. Belashchenko, Giovanni G. Baez Flores, Wuzhang Fang, Alexey Kovalev, Mark Van Schilfgaarde, Paul M. Haney, Mark D. Stiles

Department of Physics and Astronomy: Faculty Publications

Spin-accumulation and spin-current profiles are calculated for a disordered Pt film subjected to an in-plane electric current within the nonequilibrium Green's function approach. In the bulklike region of the sample, this approach captures the intrinsic spin Hall effect found in other calculations. Near the surfaces, the results reveal qualitative differences with the results of the widely used spin-diffusion model, even when the boundary conditions are modified to try to account for them. One difference is that the effective spin-diffusion length for transverse spin transport is significantly different from its longitudinal counterpart and is instead similar to the mean-free path. This …

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Discovery And Generation Mechanisms Of Epigenetic Biogenic H2S From Coal Seams In The Fukang Block, Southern Junggar Basin, China, Yan Peipei, Su Xianbo, Zou Chenglong, Zhao Weizhong, Wang Lufei, Fu Haijiao Oct 2023

Discovery And Generation Mechanisms Of Epigenetic Biogenic H2S From Coal Seams In The Fukang Block, Southern Junggar Basin, China, Yan Peipei, Su Xianbo, Zou Chenglong, Zhao Weizhong, Wang Lufei, Fu Haijiao

Coal Geology & Exploration

In the Fukang block located in the eastern part of the southern Junggar Basin, coalbed methane (CBM) from CBM wells exhibits a gradually increasing H2S concentration in the process of CBM production via water drainage, severely threatening production safety. Based on the CBM exploration and extraction data, as well as the anaerobic fermentation experiments, this study preliminarily investigated the causes of abnormal H2S concentrations during the CBM production in the Fukang block. As indicated by the gas content test in the CBM exploration stage, the original CBM showed a low H2S concentration of only …

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Statistical And Machine Learning Approaches To Describe Factors Affecting Preweaning Mortality Of Piglets, Md Towfiqur Rahman, Tami M. Brown-Brandl, Gary A. Rohrer, Sudhendu R. Sharma, Vamsi Manthena, Yeyin Shi Oct 2023

Statistical And Machine Learning Approaches To Describe Factors Affecting Preweaning Mortality Of Piglets, Md Towfiqur Rahman, Tami M. Brown-Brandl, Gary A. Rohrer, Sudhendu R. Sharma, Vamsi Manthena, Yeyin Shi

Department of Biological Systems Engineering: Papers and Publications

High preweaning mortality (PWM) rates for piglets are a significant concern for the worldwide pork industries, causing economic loss and well-being issues. This study focused on identifying the factors affecting PWM, overlays, and predicting PWM using historical production data with statistical and machine learning models. Data were collected from 1,982 litters from the United States Meat Animal Research Center, Nebraska, over the years 2016 to 2021. Sows were housed in a farrowing building with three rooms, each with 20 farrowing crates, and taken care of by well-trained animal caretakers. A generalized linear model was used to analyze the various sow, …

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Artst: Arabic Text And Speech Transformer, Hawau Olamide Toyin, Amirbek Djanibekov, Ajinkya Kulkarni, Hanan Al Darmaki Oct 2023

Artst: Arabic Text And Speech Transformer, Hawau Olamide Toyin, Amirbek Djanibekov, Ajinkya Kulkarni, Hanan Al Darmaki

Natural Language Processing Faculty Publications

We present ArTST, a pre-trained Arabic text and speech transformer for supporting open-source speech technologies for the Arabic language. The model architecture follows the unified-modal framework, SpeechT5, that was recently released for English, and is focused on Modern Standard Arabic (MSA), with plans to extend the model for dialectal and code-switched Arabic in future editions. We pre-trained the model from scratch on MSA speech and text data, and fine-tuned it for the following tasks: Automatic Speech Recognition (ASR), Text-To-Speech synthesis (TTS), and spoken dialect identification. In our experiments comparing ArTST with SpeechT5, as well as with previously reported results in …

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Methods For Estimating Carbon Emissions From Coals In Underground Mines: A Case Study Of The Western Fukang Mining Area, Peng Rendong, Wei Bo, Li Xin, Zhang Ji, Zhang Zizhao, Wang Bo, Zhang Na, Cui Deguang Oct 2023

Methods For Estimating Carbon Emissions From Coals In Underground Mines: A Case Study Of The Western Fukang Mining Area, Peng Rendong, Wei Bo, Li Xin, Zhang Ji, Zhang Zizhao, Wang Bo, Zhang Na, Cui Deguang

Coal Geology & Exploration

Carbon emissions have come into sharp focus of human society. The carbon emissions from coals rank as the most predominant part of China’s total carbon emissions. Presently, there is no available study on the accurate calculation of carbon emissions from coals in typical underground mines in Xinjiang, with the CH4 emission even overlooked. This study centers on the carbon emissions from coals in underground mines in the western Fukang mining area. As per the occurrence laws of CH4 and CO2 in coal seams, as well as coal mining plans, this study classified the sources of carbon emissions …

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A Method For Identifying Faults Within Mining Faces Based On Spatial Statistics, Feng Yajie, Wen Guangchao, Wu Bingjie, Hu Zudong Oct 2023

A Method For Identifying Faults Within Mining Faces Based On Spatial Statistics, Feng Yajie, Wen Guangchao, Wu Bingjie, Hu Zudong

Coal Geology & Exploration

Minor faults within mining faces of coal mines severely affect gas drainage and coal seam mining. Accurately identifying parameters such as positions, throws, and attitudes of these faults is of great significance for the safe production of coal mines. To effectively reduce gas emissions, prevent gas explosions, and exploit and utilize gas resources, many gas drainage holes have been drilled during the construction of coal mines, providing favorable engineering conditions for identifying minor faults within coal seams. Compared with the conventional fault identification methods, which rely on the expertise of geologists, the identification model based on mathematical statistics and space …

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Water-Blocking Performance Of Laterite In Weak Deposition Areas Of Neogene Baode Formation And Its Significance Of Resource Exploitation, Zeng Yifan, Bao Han, Wu Qiang, Meng Shihao, Hua Zhaolai, Miao Yanping, Zhang Ye, Bu Wenyang Oct 2023

Water-Blocking Performance Of Laterite In Weak Deposition Areas Of Neogene Baode Formation And Its Significance Of Resource Exploitation, Zeng Yifan, Bao Han, Wu Qiang, Meng Shihao, Hua Zhaolai, Miao Yanping, Zhang Ye, Bu Wenyang

Coal Geology & Exploration

The in-depth study on the water-blocking performance of laterite in the weak deposition areas of the key aquiclude is of significant importance for mine production safety and ecological water resource protection. Specifically, the borehole data were re-optimized based on the regional sedimentary characteristics, the thickness distribution pattern of laterite deposit in Yushen mining area was studied, and the micro-engineering characteristics and control factors related to the water-blocking performance of laterite were explored. The results show that the deposition thickness of laterite gradually increases from northwest to southeast, the distribution of laterite becomes extremely uneven with the evolution of rivers, and …

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Pfc Numerical Analysis On Crack Initiation Mechanism Of Fracture Grouting In Top Of Ordovician Limestone, Liu Zhaoxing, Zhang Qi Oct 2023

Pfc Numerical Analysis On Crack Initiation Mechanism Of Fracture Grouting In Top Of Ordovician Limestone, Liu Zhaoxing, Zhang Qi

Coal Geology & Exploration

The advanced regional grouting is an effective means to prevent and control the water hazard of limestone in coal seam floor, and the fracture grouting projects is a key link to determine the effect of the grouting in floor against water hazard. However, due to the unclear understanding of the fracture initiation mechanism of the injected limestone stratum, the grouting pressure, grout water-cement ratio and other grouting parameters in the process of fracture grouting are not effectively controlled. Thus, it is difficult to guarantee the grouting effect. In order to solve the above problems, numerical simulation calculation was conducted for …

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Numerical Model Of Two-Region Flow By Constant-Head Pumping In An Unconfined Aquifer, Shi Pengyu, Zong Yijie, Teng Kaiqing, Liu Jianjun, Xiao Liang Oct 2023

Numerical Model Of Two-Region Flow By Constant-Head Pumping In An Unconfined Aquifer, Shi Pengyu, Zong Yijie, Teng Kaiqing, Liu Jianjun, Xiao Liang

Coal Geology & Exploration

In order to reveal the mechanism of two-region Darcian and non-Darcian flow induced by constant-head pumping tests in unconfined aquifers, a numerical model of well flow by constant-head pumping underground based on finite difference solution was proposed. In the model, it is assumed that the aquifer is divided into two regions according to the pumping flow characteristics: the finite non-Darcian flow region near the pumping well and the semi-infinite Darcian flow region far away from the pumping well. Specifically, the flow regime in the non-Darcian flow region was simulated by the Izbash’s equation, and the reliability of the proposed solution …

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Study On Mesoscopic Failure Characteristics Of Layered Red Shale, Ma Zhenqian, Zhou Lang, Zuo Yujun, Zhang Jimin, Zou Yihuai, Cao Yunqin Oct 2023

Study On Mesoscopic Failure Characteristics Of Layered Red Shale, Ma Zhenqian, Zhou Lang, Zuo Yujun, Zhang Jimin, Zou Yihuai, Cao Yunqin

Coal Geology & Exploration

To study the mesoscopic failure characteristics of the layered red shale, uniaxial mechanical experiments were carried out by applying DSTD-1000 electro-hydraulic servo rigid pressure on the red shale with different bedding angles. Meanwhile, SEM and XRD experiments were implemented on debris to obtain its mechanical parameters, failure characteristics, microstructure, and relative content of components. Based on this, models of the red shale with different bedding angles were constructed using the discrete element PFC3D for the uniaxial compression experiments to study the mesoscopic failure characteristics of red shale. The results show that: (1) When the bedding angle θ=30°, 45°, …

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An Attention Mechanism-Based Cnn-Bilstm Real-Time Transient Electromagnetic Method, Gu Yao, Xie Haijun, Zhou Zipeng, Li Lu Oct 2023

An Attention Mechanism-Based Cnn-Bilstm Real-Time Transient Electromagnetic Method, Gu Yao, Xie Haijun, Zhou Zipeng, Li Lu

Coal Geology & Exploration

The one-dimensional transient electromagnetic (TEM) method is time-consuming and suffers other drawbacks such as difficult parameter adjustment and heavy dependence on the initial model. Therefore, this study proposed a real-time TEM inversion method—the Attention mechanism-based convolutional neural network (CNN) - bidirectional Long Short-Term Memory (BiLSTM) (AC-BiLSTM). By fully utilizing the time difference, the AC-BiLSTM performed model training in non-observation time and the real-time inversion of the collected data in observation time. With the measured data mixed with a certain proportion of data obtained from forward modeling as the dataset, the sampling time and apparent resistivity as the input features in …

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