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Articles 4021 - 4050 of 292873
Full-Text Articles in Entire DC Network
An Infinite Set Of One-Range Addition Theorems Without An Infinite Second Series, For Slater Orbitals And Their Derivatives, Applicable To Multiple Coordinate Systems, Jack C. Straton
Physics Faculty Publications and Presentations
Addition theorems have been indispensable tools for the reduction of quantum transition amplitudes. They are normally utilized at the start of the process to move the angular dependence within plane waves, Coulomb potentials, and the like, into a sum over spherical harmonics that allows the angular integration to be carried out. These have historically been “two-range” addition theorems, characterized by the two-fold notation r>=Max[r1,r2] and r< =Min[r1,r2] and comprising a single infinite series. More recently, “one-range” addition theorems have been created that have no such piecewise notation, but at the cost of the introduction of another infinite series. We use a very different approach to derive an infinite set of addition theorems for Slater orbitals, hydrogenic and Hylleraas wave functions, and so on, that retain the one-range variable dependence but have, at worst, a finite second series rather than an infinite one. In addition, unlike previous addition theorems, they are applicable to more than one coordinate system. One of these addition theorems may also be used for Yukawa-like functions that may appear late in the reduction of amplitude integrals, and we show its utility for an integral that has stubbornly defied reduction to analytic form for nearly sixty years. Finally, we craft indefinite integrals of 15 half-integer Macdonald functions multiplied by (inverse) powers and negative exponentials containing squares of the integration variable.
Open Multi-Agent Systems: The Free-Range-Zoo Framework And Moasei Competition, Ceferino J. Patino Iv
Open Multi-Agent Systems: The Free-Range-Zoo Framework And Moasei Competition, Ceferino J. Patino Iv
School of Computing: Dissertations, Theses, and Student Research
The field of multi-agent reinforcement learning (MARL) has made significant strides in addressing sequential decision-making problems under uncertainty. However, traditional MARL frameworks assume closed-world settings with fixed agent sets, static task distributions, and unchanging environment dynamics. This thesis presents two complementary contributions that advance the state of open-world multi-agent systems research: (1) the free-range-zoo framework, an open-source environment suite for MARL in open environments featuring dynamic agent populations, evolving task sets, and changing operational frames; and (2) the MOASEI Competition, an international benchmarking event that leverages free-range-zoo to evaluate how artificial agents handle openness in complex, partially observable domains. The …
Initiatives To Grow New Innovative Talent To Enable Fusion Energy, Peng Zhang, Ranganathan Parthasarathy, Yuqiao Fan, Arnold Lumsdaine, Rinkle Juneja, Yuchen Jiang, Monica Gehrig, Louise Ferris, David Donovan, Firas Akasheh, Olakunle Harrison, Joshua Schlegel, Manish Sharma, Mohammad Habibi, Mohan Rao, Rajni Chahal, Sean Walters, Vola Andrianarijaona
Initiatives To Grow New Innovative Talent To Enable Fusion Energy, Peng Zhang, Ranganathan Parthasarathy, Yuqiao Fan, Arnold Lumsdaine, Rinkle Juneja, Yuchen Jiang, Monica Gehrig, Louise Ferris, David Donovan, Firas Akasheh, Olakunle Harrison, Joshua Schlegel, Manish Sharma, Mohammad Habibi, Mohan Rao, Rajni Chahal, Sean Walters, Vola Andrianarijaona
Achieve
The Initiatives to Grow New Innovate Talent to Enable Fusion Energy (IGNITE Fusion Energy) project was launched under the U.S. Department of Energy’s Reaching a New Energy Sciences Workforce (RENEW) program. This DOE RENEW-funded project is a multi‑institutional program that aims to build the future fusion workforce through mentoring, curriculum development, and innovation bootcamps. IGNITE brings together six academic institutions (Tennessee Tech University, Tennessee State University, Tuskegee University, Southern Adventist University, Missouri University of Science Technology, and University of Tennessee–Knoxville), Oak Ridge National Laboratory (ORNL) as a research and partnership hub, and 11+ private fusion companies for industry input and …
The Intersection Of Visual Communications, User Experience, & Design Theory: A Case Study With The Dog Spaw, Jessica Miltner
The Intersection Of Visual Communications, User Experience, & Design Theory: A Case Study With The Dog Spaw, Jessica Miltner
Honors Projects
This project explored the intersection of visual communication, user experience, and design theory, focusing on researching design and UX principles and applying them in a real-world case study with The Dog Spaw from Celina, Ohio. The project resulted in a redesigned website that aims to influence user behavior by improving perceptions of trust, professionalism, brand consistency, and ease of use, and by examining how these perceptions, in turn, influence user action.
Evaluating Acridones As Novel Therapeutics For Human Babesiosis, Pratap Vydyam, Elizabeth Zhang, Papireddy Kancharla, Rozalia A. Dodean, Jane X. Kelly
Evaluating Acridones As Novel Therapeutics For Human Babesiosis, Pratap Vydyam, Elizabeth Zhang, Papireddy Kancharla, Rozalia A. Dodean, Jane X. Kelly
Chemistry Faculty Publications and Presentations
Human babesiosis is an emerging tick-borne disease caused by Babesia parasites, most notably Babesia microti and Babesia duncani in North America and Babesia divergens in Europe. Infections can be severe or persistent or relapse despite treatment, and current therapeutic options remain limited, underscoring the urgent need for new and effective treatment options. Acridone derivatives originally developed as potent antimalarial agents against multiple life cycle stages of the malaria parasites were evaluated for their antibabesial activity using continuous in vitro culture systems of B. duncani and B. divergens. Lead candidates were assessed for selectivity against human cell lines to establish preliminary …
Evaluation Of Sirna-Mediated Knockdown Of Heat Shock Protein 16.2 In Adult Acropora Cervicornis, Edward P. Gniffke, Benjamin D. Young, Keir J. Macartney, Michael S. Studivan, Ian C. Enochs, Erin E. Easton
Evaluation Of Sirna-Mediated Knockdown Of Heat Shock Protein 16.2 In Adult Acropora Cervicornis, Edward P. Gniffke, Benjamin D. Young, Keir J. Macartney, Michael S. Studivan, Ian C. Enochs, Erin E. Easton
School of Earth, Environmental, & Marine Sciences Faculty Publications
Acropora cervicornis is a critically endangered Caribbean coral species facing a precipitous decline due to disease and thermal bleaching. To combat the loss of ecologically important reef-building corals, novel molecular approaches can be used to understand mechanisms of resilience and ultimately provide a means to modulate coral performance. In this study, we tested a recently developed method for gene knockdown in adult corals that utilizes short interfering RNAs (siRNAs) and the RNA interference pathway. The Heat Shock Protein 16.2 (HSP16.2) gene in fragments of adult A. cervicornis was targeted for knockdown using a single siRNA construct. RT-qPCR analysis of HSP16.2 …
Developing A Framework To Improve Phishing Response After Detection, Kevin Umba
Developing A Framework To Improve Phishing Response After Detection, Kevin Umba
Master's Theses (2009 -)
Phishing belongs to the most prevalent attack vectors in the cybersecurity industry. Academia, industry, and government resources offer a wealth of information on the subject. However, insights on phishing techniques and remediations are scattered across those sources. Most governmental and academic literature focuses on user awareness, policy guidelines, or phishing training. This leaves the security practitioners underserved. Furthermore, actionable information for security operations is often unstructured or vendor-specific. The goal of the thesis is to provide a preliminary framework to guide security professionals through indicators of compromise and remediation, using a vendor-neutral approach.
Writing As A Process Of Inquiry In Autoethnography For Meaning-Making: Reflections And Some Points For Consideration, Niroj Dahal
Writing As A Process Of Inquiry In Autoethnography For Meaning-Making: Reflections And Some Points For Consideration, Niroj Dahal
The Qualitative Report
This article explores writing as a process of inquiry and meaning-making in the autoethnographic tradition, offering reflections on the recursive, emergent, and dialogical/dialectical nature of writing, along with some points for consideration. Drawing on perspectives from qualitative research and narrative inquiry (Riessman, 2008), I argue that autoethnographic writing serves as a method of inquiry and/or discovery, generating ontological, epistemological, and axiological-driven cultural meaning that functions as a site of reflection, interrogation, and re-storying of lived experiences. This recursive, often messy, and reflexive act allows researchers to excavate, analyze, and interpret their lived experiences. Rather than viewing writing as a final-stage …
Fast Hyperspectral And Super-Resolved Mapping Of Lipid Membrane Polarity With Single-Molecule Sensitivity, Elric Dion Pott, Meek Yang, James Ethan Batey, Jole Embree, Bin Dong
Fast Hyperspectral And Super-Resolved Mapping Of Lipid Membrane Polarity With Single-Molecule Sensitivity, Elric Dion Pott, Meek Yang, James Ethan Batey, Jole Embree, Bin Dong
Chemistry & Biochemistry Faculty Publications and Presentations
Cell membranes display nanoscale heterogeneity in lipid composition and organization that regulates vital biological processes yet remain challenging to resolve with conventional imaging. We introduce spectral phasor single-molecule localization microscopy (SP-SMLM), a hyperspectral and super-resolution method that combines wavefront-like optical filtering with single-molecule imaging for simultaneous spatial and spectral analysis. A lab-built three-channel imager with sine/cosine filters encodes emission spectra of single molecules into the phasor space, enabling high-throughput, high-SNR mapping of membrane polarity at sub-50 nm spatial and 15 s temporal resolutions. Through simulation, we validate that the phasor angle correlates with the spectral mean for single dye molecules. …
3Ω Thermal Transport In Atomically Thin Materials, Yiwei Le
3Ω Thermal Transport In Atomically Thin Materials, Yiwei Le
Arts & Sciences Graduate Student Theses and Dissertations
Since the discovery of graphene, research on two-dimensional (2D) materials has become a central focus of condensed matter physics. While an enormous number and variety of investigations of their electrical, optical, and mechanical properties have been undertaken, their thermal properties remain comparatively underexplored, despite the importance for understanding low-energy excitations and phase transitions. Here, we introduce an extension of the 3ω method thermal measurement technique to the 2D limit of materials. We develop analytical models of thermal transport in the 3ω geometry with boundary conditions tailored for suspended 2D flakes. We then experimentally confirm the feasibility of this approach in …
Static And Dynamic Properties Of Dense Matter, Liam Brodie
Static And Dynamic Properties Of Dense Matter, Liam Brodie
Arts & Sciences Graduate Student Theses and Dissertations
Neutron stars and their mergers create environments of ultra-dense matter where the strong interaction governs the behavior, but where quantum chromodynamics, the theory of the strong interaction, cannot be solved exactly or perturbatively using current methods. Neutron stars are objects with more mass than our Sun, but with a diameter of about 25 km. Observations of neutron star macroscopic properties like their masses and radii, their surface temperatures, and the gravitational-wave and electromagnetic signals from their mergers allow us to use theoretical tools to infer the behavior of matter at a microscopic scale. In this thesis, we explore the static …
The Role Of Interactions In Moiré Quantum Materials, Liangtao Peng
The Role Of Interactions In Moiré Quantum Materials, Liangtao Peng
Arts & Sciences Graduate Student Theses and Dissertations
Moiré quantum materials have emerged as a highly tunable platform for studying strongly interacting electrons in low dimensions. By twisting or lattice-mismatching atomically thin crystals, one can generate long-wavelength moiré superlattices that reconstruct the electronic bands, produce narrow bandwidths, and greatly enhance the importance of Coulomb interactions. As a result, these systems host a wide range of correlated phenomena, including symmetry breaking, magnetism, and superconductivity. This dissertation develops and applies Green's-function-based many-body methods to understand the role of interactions in moiré quantum materials. This dissertation consists of four chapters. The first chapter introduces moiré quantum materials and reviews the basic …
Advancing High-Energy Astrophysics Through X-Ray Spectropolarimetry And Balloon-Borne Instrumentation, Sohee Chun
Advancing High-Energy Astrophysics Through X-Ray Spectropolarimetry And Balloon-Borne Instrumentation, Sohee Chun
Arts & Sciences Graduate Student Theses and Dissertations
The strong gravitational field around black holes provides a unique laboratory for investigating the behavior of matter and radiation under extreme conditions. As matter accretes, the interplay between the accretion disk, hot corona, and surrounding stellar environment produces complex spectral and polarimetric X-ray signatures. Thus, X-ray spectropolarimetry has become a powerful tool for constraining the accretion geometry. Building on these advances, this dissertation integrates theoretical modeling, observational data analysis, and instrumentation development to address open questions in high-energy astrophysics. On the theoretical side, relativistic ray-tracing simulations test the truncated disk-hot inner flow accretion geometry against observations of Cygnus X-1, identifying …
Development Of New Technical Approaches To Speed The Search For Axion Dark Matter With Haloscopes, Jonah Harper Hoffman
Development Of New Technical Approaches To Speed The Search For Axion Dark Matter With Haloscopes, Jonah Harper Hoffman
Arts & Sciences Graduate Student Theses and Dissertations
The axion is a hypothetical particle that may solve two major problems in physics: the strong CP problem in quantum chromodynamics (QCD) and the unknown particle nature of the dark matter. Axion haloscopes like the Axion Dark Matter eXperiment (ADMX) are capable of probing the region of parameter space where axions could constitute the dark matter. These experiments use a microwave resonant cavity in a strong magnetic field to convert axions into detectable photons when their Compton wavelength matches the resonant mode of the cavity. By moving a metal rod within the cavity volume, the resonant frequency can be tuned, …
Programmable Metal−Organic Complex Arrays With Precisely Controlled Metal Sequences As Tunable Multinuclear Scaffolds, Ahmed Alzamly, Sajid Ali
Programmable Metal−Organic Complex Arrays With Precisely Controlled Metal Sequences As Tunable Multinuclear Scaffolds, Ahmed Alzamly, Sajid Ali
Faculty Scholarship
Metal−Organic Complex Arrays (MOCAs) offer a modular framework for creating multinuclear systems with precise control over metal ion identity and sequencing at the molecular scale. This structural accuracy allows researchers to investigate how specific metal arrangements dictate cooperative phenomena, such as catalytic efficiency, electronic interactions, and photophysical responses. Recent breakthroughs in synthetic strategies including orthogonal protection and periodic metalation have enabled the fabrication of highly predictable heterometallic structures. This Review explores the fundamental principles of MOCAs’ sequence control, contemporary fabrication techniques, and the relationship between metal placement and emergent properties. Additionally, it examines applications of MOCA in catalysis, sensing, and …
Gopher: Efficient Dynamic Graph Pattern Mining Via Dag-Driven Execution, Yi Zhang, Yu Huang, Chaoqiang Liu, Haifeng Liu, Juntao Chen, Jingrui Yuan, Jianhui Yue, Xiaofei Liao, Hai Jin, Jingling Xue
Gopher: Efficient Dynamic Graph Pattern Mining Via Dag-Driven Execution, Yi Zhang, Yu Huang, Chaoqiang Liu, Haifeng Liu, Juntao Chen, Jingrui Yuan, Jianhui Yue, Xiaofei Liao, Hai Jin, Jingling Xue
Michigan Tech Publications
Graph pattern mining is essential for analyzing dynamic networks, where graphs evolve over time. To accommodate these changes, existing solutions update match sets incrementally, avoiding the need to re-mine the entire graph and achieving significant performance improvements. However, these methods suffer from inefficiencies due to redundant set intersection operations across subgraph instances, causing performance degradation. In this paper, we propose Gopher, a DAG-driven dynamic graph pattern mining system that leverages computation locality for enhanced performance. Gopher uses DAGs to represent set operations, identifying and merging common subexpressions at compile time. This reduces redundant computations during runtime. To maximize performance, we …
Re: Approval Letter For The Butte Priority Soils Operable Unit (Bpsou) Draft Final Whitehall Borrow Submittal #3 (Dated March 27, 2026), Molly Roby
Silver Bow Creek/Butte Area Superfund Site
No abstract provided.
2026 - The Thirtieth Annual Symposium Of Student Scholars
2026 - The Thirtieth Annual Symposium Of Student Scholars
Symposium of Student Scholars Program Books
The full program book from the 30th Annual Symposium of Student Scholars, held on April 22-24, 2026. Includes abstracts from the presentations and posters.
Table Of Contents, The Editors
Machine Learning-Based Prediction And Experimental Validation Of The Pyrolysis Product Distribution In Tar-Rich Coals, Dong Shuai, Li Hongqiang, Wu Zhiqiang, Yu Zunyi, Lyu Zitao, Guo Wei, Yang Panxi, Fu Keming, Hao Xuanzhi, Liu Gen, Yang Bolun
Machine Learning-Based Prediction And Experimental Validation Of The Pyrolysis Product Distribution In Tar-Rich Coals, Dong Shuai, Li Hongqiang, Wu Zhiqiang, Yu Zunyi, Lyu Zitao, Guo Wei, Yang Panxi, Fu Keming, Hao Xuanzhi, Liu Gen, Yang Bolun
Coal Geology & Exploration
Background Tar-rich coals serve as an important coal-based oil and gas resource in China, while their pyrolysis product distribution is governed by the coupling effects of coal properties and reaction conditions. Therefore, rapidly identifying the pyrolysis product distribution patterns holds great significance for the resource evaluation and experimental design of tar-rich coals.Methods Existing studies on tar-rich coals suffer from the insufficient integration of exclusive data and limited synergistic prediction capacities for multiple products. To address these issues, this study constructed a dedicated dataset involving proximate analysis, ultimate analysis, elemental molar ratios, maceral composition, and pyrolysis conditions by systematically collecting …
Evaluation And Research Progress Of Co2 Sequestration In Deep Coal Seams, Xiong Yucan, Xu Shi’Ang, Zhang Pingsong, Lu Haifeng, Jia Yunzhong, Ge Binbin, Li Baiqiang, Liu Chang, Lei Jian, Fu Wenyu
Evaluation And Research Progress Of Co2 Sequestration In Deep Coal Seams, Xiong Yucan, Xu Shi’Ang, Zhang Pingsong, Lu Haifeng, Jia Yunzhong, Ge Binbin, Li Baiqiang, Liu Chang, Lei Jian, Fu Wenyu
Coal Geology & Exploration
Background With increasing pressure for global carbon emission reduction, geologic CO2 sequestration has emerged as a critical technical approach to achieving the goals of peak carbon dioxide emissions and carbon neutrality. Owing to their high CO2 adsorption capacity and favorable sealing conditions, deep coal seams are considered one of the most promising media for CO2 sequestration, following saline aquifers and depleted hydrocarbon reservoirs. Therefore, the exploitation and utilization of deep coal seams hold significant strategic importance for the green, low-carbon transformation of the coal industry. Methods Based on literature analysis and a review of outcomes from cutting-edge …
Mechanisms Behind The Impacts Of Co2 Concentration On Microbial Methanogenesis In Coal Seams, Wang Junyu, Liu Bingjun, Jiang Xiangqing, Chen Ruifeng, Xue Sheng, Zhou Wanlong, Yang Yundu
Mechanisms Behind The Impacts Of Co2 Concentration On Microbial Methanogenesis In Coal Seams, Wang Junyu, Liu Bingjun, Jiang Xiangqing, Chen Ruifeng, Xue Sheng, Zhou Wanlong, Yang Yundu
Coal Geology & Exploration
Background Coal seams exhibit the extensive distribution of a variety of indigenous functional microorganisms. Among these, some archaea enable methane metabolism using CO2 as a substrate, providing the potential for the biological CO2 storage and utilization in coal seams. However, conventional studies focus primarily on the degradation characteristics of coal matrix, leading to a lack of a systematic understanding of the mechanisms governing the adjustment of the methanation process in CO2-bearing environments. Methods This study investigated the bituminous coals with a high volatile content in the Huainan mining area. Using laboratory-scale experiments on methanogenesis through anaerobic …
Dynamic Prediction On Goaf Surface Subsidence For The Last Two Periods Based On The Erf Time Function, Ren Lianwei, Li Shihui, Wang Wenchang, Li Zhenhua, Chen Shaojie, Dun Zhilin
Dynamic Prediction On Goaf Surface Subsidence For The Last Two Periods Based On The Erf Time Function, Ren Lianwei, Li Shihui, Wang Wenchang, Li Zhenhua, Chen Shaojie, Dun Zhilin
Coal Geology & Exploration
Background The surface subsidence induced by coal seam mining represents a continuous dynamic evolution process. Constructing a full-time perdition model for surface subsidence in goafs holds significant theoretical and practical values for the rational utilization of land resources, the safety guarantee of engineering construction, and the transformation and development of resource-based cities. Methods To accurately predict the surface subsidence in goafs during its decline and residual periods, this study proposed a prediction model based on the error function (Erf). First, the evolution characteristics of Erf were analyzed, verifying that the subsidence, as well as its velocity and acceleration, predicted using …
Performance Optimization Of Superfine Cement Through Composite Modification Using Coal-Based Solid Waste And Modifiers, Kang Zhipeng, Luo Yong, Xiao Diancai, Ren Shuai, Cai Zhiliang, Gao Xiang, Zhang Kunzhe
Performance Optimization Of Superfine Cement Through Composite Modification Using Coal-Based Solid Waste And Modifiers, Kang Zhipeng, Luo Yong, Xiao Diancai, Ren Shuai, Cai Zhiliang, Gao Xiang, Zhang Kunzhe
Coal Geology & Exploration
Objective Superfine cement-based grouting materials generally suffer from limitations including high bleeding rates, unfavourable rheological properties, poor stability, and strength retrogression. These issues can be mitigated by incorporating modifiers, which allows for the reutilization of coal-based solid waste while enhancing the performance of composite, superfine cement-based grouting materials. Methods Superfine cement-based grouting materials with different mixing ratios were prepared by using superfine cement as the basic material, fly ash (FA) and mineral fines (MFs) as primary admixtures, and modified bentonite, methyl cellulose ether (MCE), U-type expansive agent (UEA), and magnesium oxide (MgO) as modifiers. These grouting materials and pure superfine …
Dynamic Response Characteristics And Failure Mechanism Of Coal-Rock Combination Under Different Immersion Conditions, Zhang Xiangyang, Tong Zhipeng, Duan Yungang, Yang Weikun, Chen Jianben, Xu Linfeng
Dynamic Response Characteristics And Failure Mechanism Of Coal-Rock Combination Under Different Immersion Conditions, Zhang Xiangyang, Tong Zhipeng, Duan Yungang, Yang Weikun, Chen Jianben, Xu Linfeng
Coal Geology & Exploration
Background In practical engineering, the waterproof coal pillar usually suffers from different degrees of dynamic load from the overlying strata, and its internal water distribution is non-uniform. Although the traditional “water content” index can reflect the overall water content, it is difficult to describe the non-uniform characteristics of the soaking space. Therefore, it is of great significance to clarify the dynamic failure mechanism of coal and rock mass under different immersion conditions for stability zoning control. Methods On this basis, the coal–rock combined bodies under three different forms of immersion, namely: complete immersion, unilateral immersion, and non-immersion were prepared. These …
Mine Data Fusion Technology Based On Multi-Feature Joint Decision Making, Han Shanshan, Zhang Jifeng, Fan Tao, Liu Qiang, Song Xiaojiao, Qi Zhipeng, Zheng Hangzhou
Mine Data Fusion Technology Based On Multi-Feature Joint Decision Making, Han Shanshan, Zhang Jifeng, Fan Tao, Liu Qiang, Song Xiaojiao, Qi Zhipeng, Zheng Hangzhou
Coal Geology & Exploration
Background In the field of geological exploration of coal mines, methods such as in-seam seismic exploration, the transient electromagnetic method, and audio-frequency electrical penetration offer unique technical advantages. However, each of these methods can only reflect a single physical property of a medium, suffering from limitations including the one-sidedness of information and the multiple solutions of interpretations, thus failing to adapt to the new situations of current coal mine exploration. Multi-source data fusion promotes a technological development by leaps from one-sided detection to comprehensive analysis through mechanisms of information complementation, feature enhancement, and field-source integration. Therefore, this technology can enhance …
Mechanisms Underlying Lateral Force Applied To A Pdc Cutter On A Pdc Drill Bit During Rotary Rock Breaking, Wei Jiusen, Han Xin, Liu Wei, Gao Deli
Mechanisms Underlying Lateral Force Applied To A Pdc Cutter On A Pdc Drill Bit During Rotary Rock Breaking, Wei Jiusen, Han Xin, Liu Wei, Gao Deli
Coal Geology & Exploration
Objective To improve the rock-breaking efficiency and durability of drill bits in the theoretical research on the optimal design of drill bits, the key is to systematically reveal both the rock-breaking mechanisms of polycrystalline diamond compact (PDC) cutters and the characteristics of forces applied to them. Methods Existing studies on rock breaking using a single PDC cutter generally adopt a linear or approximately linear cutting mode while neglecting the impacts of the radius of gyration. To address this issue, this study conducted experiments on cylindrical granite samples using a laboratory experimental setting for single-cutter rock breaking. With cutting depth and …
Strategic Layout And Optimization Paths Of The Standard System For The Exploration And Exploitation Of Deep Coalbed Methane, Chen Xinjun, Liu Zengqin, Shen Baojian, Zhao Shihu, Ye Jincheng, Zhang Jiaqi, Wang Tianyun
Strategic Layout And Optimization Paths Of The Standard System For The Exploration And Exploitation Of Deep Coalbed Methane, Chen Xinjun, Liu Zengqin, Shen Baojian, Zhao Shihu, Ye Jincheng, Zhang Jiaqi, Wang Tianyun
Coal Geology & Exploration
Objective In China, the deep coalbed methane (CBM) industry has emerged as a key sector for the reserve growth and production addition of natural gas. However, the current CBM technical standard system, which was developed based on shallow CBM practices, is incompatible with the demands for the exploration and development of deep CBM. To address this challenge, this study proposes the optimization paths of the current standard system, aiming to provide standardization support for large-scale exploitation of deep CBM.Methods Deep CBM reservoirs exhibit complex geological conditions of high temperature, pressure, and in-situ stress, as well as the CBM occurrence …
Parameter Optimization And Field Application Of Roof Volume Fracturing Using Horizontal Wells For Coalbed Methane Extraction From Broken-Soft Coal Seams, Zhang Qingli, Sun Siqing, Li Haozhe, Wu Xiaoxuan, Yang Fan, Zheng Yuqi, Li Wenbo
Parameter Optimization And Field Application Of Roof Volume Fracturing Using Horizontal Wells For Coalbed Methane Extraction From Broken-Soft Coal Seams, Zhang Qingli, Sun Siqing, Li Haozhe, Wu Xiaoxuan, Yang Fan, Zheng Yuqi, Li Wenbo
Coal Geology & Exploration
Objective and Method To achieve rapid coalbed methane (CBM) extraction from broken-soft coal seams using surface horizontal wells, this study proposed a volume fracturing technology for coal seam roof using horizontal wells. Focusing coal seam 4-1 in a mining area, this study established a numerical model using finite element analysis (FEA) software Abaqus Using this model, the impacts of in-situ stress on the cross-layer propagation characteristics of multiple fractures were investigated. Through true triaxial hydraulic fracturing experiments, the multi-fracture propagation patterns under varying injection rates of fracturing fluids, perforation cluster numbers, and cluster spacings were analyzed. Using 3D fracturing design …
Structural Design And Parameter Optimization Of A Vibration Absorber For Rescue Casing-While-Drilling Rigs, Liu Pu, Yao Ningping, Zou Zujie, Fan Dong, Wei Hongchao, He Binjie
Structural Design And Parameter Optimization Of A Vibration Absorber For Rescue Casing-While-Drilling Rigs, Liu Pu, Yao Ningping, Zou Zujie, Fan Dong, Wei Hongchao, He Binjie
Coal Geology & Exploration
Objective Rescue drilling rigs undergo intense vibration at borehole mouths when operating in a confined underground space of coal mines. To address this issue, this study designed a compact multi-directional, passive dynamic vibration absorber, aiming to improve the operational stability and safety of the rigs. Methods Based on the spring-mass-damping system theory, a stepwise optimization design method was proposed for the longitudinal and transverse dynamic models of the vibration absorber. For the longitudinal vibration model, the particle swarm optimization (PSO) algorithm was applied for multi-objective parameter optimization. In contrast, for the transverse vibration model, the fixed point theory was employed …