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Full-Text Articles in Physical Sciences and Mathematics
Hydrus Modeling Of A Sahelian Agroforestry System: An Investigation Of Local Water Balance, Nicole A. Butler
Hydrus Modeling Of A Sahelian Agroforestry System: An Investigation Of Local Water Balance, Nicole A. Butler
Master's Theses
Effects of drought can devastate agricultural productivity in the West African Sahel. Climate complexities, such as lower-than-average rainfall and high winds, can lead to crop failure and low yields, thereby creating food security issues. Agriculture in the Sahel is primarily rainfed, and the rain is becoming increasingly unpredictable due to the changing climate. The method of intercropping groundnut (Arachis hypogea) and pearl millet (Pennisetum glaucum) with the shrub species Piliostigma reticulatum can combat the effects of climate change and restore degraded soil. Intercropping can increase water availability and crop yield when compared to crops grown in the absence of shrubs. …
Monoids With K-Strictly Local Geodesic Languages, William M. Hong
Monoids With K-Strictly Local Geodesic Languages, William M. Hong
Master's Theses
A paper by Gilman, Hermiller, Holt and Rees (2011) prove that a group G finitely generated by X is virtually free if and only if the language of geodesics words in G over X is k-strictly local if and only if the word problem is context-free. If M is a monoid finitely generated by X, we define Γu(M,X) to be the underlying, undirected graph of Γ(M,X). We prove that if the language of geodesics in Γu(M,X) based at the identity is k-strictly local, then the monoid and semi-group word problems are context-free.
Probabilistic Metric Dimension, Kyle Worley
Probabilistic Metric Dimension, Kyle Worley
Master's Theses
The metric dimension of a graph G is the smallest number of unique vertices (often called “marked vertices” or “landmarks”) such that each vertex has a unique distance to the marked vertices. If a set of vertices S ⊆ V (G) when marked gives all vertices unique distances, it is called a resolving set. Hence if G is a graph with a resolving set S, then for all v, u ∈ V (G) there exists s ∈ S such that d(v, s) ̸= d(u, s). The metric dimension dim(G) = min(|S|). Two widely studied variants exist, one where edges are …
Rational Non-Euclidean Triangles And Elliptic Curves, Tyler Morales
Rational Non-Euclidean Triangles And Elliptic Curves, Tyler Morales
Master's Theses
We say a triangle △ is rational if its side lengths are rational. For a geometry of constant curvature κ, we say △ is a rational triangle if the generalized tangents of its side lengths are rational. We are able to parameterize rational triangles having the same inradius and semiperimeter on an plane curve, write a bijection between the rational points on this curve and triples of side lengths, and show that this curve is an elliptic curve. Then, we write a general transformation for our plane curve to short Weierstrass form to compute ranks and add points easily using …
Hybrid Microbial-Enzymatic Electrosynthesis For De Novo Decanoic Acid Production From Co2, Yongze Wang, Wenjin Dong, Meijing Wei, Su Song, Zhiqing Huang, Yaojie Liu, Shelley D. Minteer, Hui Chen
Hybrid Microbial-Enzymatic Electrosynthesis For De Novo Decanoic Acid Production From Co2, Yongze Wang, Wenjin Dong, Meijing Wei, Su Song, Zhiqing Huang, Yaojie Liu, Shelley D. Minteer, Hui Chen
Chemistry Faculty Research & Creative Works
The steady increase in atmospheric CO2 levels is a key driver of anthropogenic climate change, prompting widespread global concern. In this context, the sustainable conversion of CO2 into value-added chemicals represents an attractive route toward carbon-neutral manufacturing and green chemistry. Here, we developed a proof-of-concept hybrid microbial-enzymatic electrosynthesis system that combines microbial electrosynthesis (MES) and enzymatic electrosynthesis (EES) to convert CO2 into decanoic acid under ambient conditions, using electrical energy. In the MES module, CO2 was converted to acetate via the Wood–Ljungdahl pathway of Clostridium ljungdahlii, using H2 produced by electrochemical water splitting as the electron …
Fermat's Last Theorem Over Quadratic Number Fields, Richie Tay
Fermat's Last Theorem Over Quadratic Number Fields, Richie Tay
Master's Theses
Fermat’s Last Theorem states that the equation xn + yn = zn has no nontrivial integer solutions for n ≥ 3. While the rational case is completely solved, the situation over quadratic number fields is not as straightforward. For some exponents nontrivial solutions exist, while for others they do not. This thesis studies Fermat-type equations over quadratic number fields, combining classical methods with more modern techniques from the theory of elliptic curves. The thesis first reviews the rational cases n = 2, n = 3, n = 4, then develops the necessary background on quadratic number fields, including rings of …
Math 141 Calculus I (Queens College), Anisha Clarke
Math 141 Calculus I (Queens College), Anisha Clarke
Open Educational Resources
This syllabus provides the outline for a calculus one course using OpenStax Calculus Volume I and no graphing calculator.
Deep Neural Networks: A Formulation Via Non-Archimedean Analysis, Wilson A. Zuniga-Galindo
Deep Neural Networks: A Formulation Via Non-Archimedean Analysis, Wilson A. Zuniga-Galindo
School of Mathematical & Statistical Sciences Faculty Publications
We introduce a new class of deep neural networks (DNNs) with multilayered tree-like architectures. The architectures are codified by using numbers in the ring of integers of non-Archimedean local fields. These rings have a natural hierarchical organization as infinite rooted trees. Natural morphisms on these rings allow us to construct finite multilayered architectures. The new DNNs are robust universal approximators of real-valued functions defined on the mentioned rings. We also show that the DNNs are robust universal approximators of real-valued square-integrable functions defined in the unit interval.
Inferring Host Environment Properties And Gravitational-Wave Decay Time From The Eccentricity Measurement Of Dynamically Captured Binaries, A. Vincent Paul, Parthapratim Mahapatra, Marc Favata, K. G. Arun
Inferring Host Environment Properties And Gravitational-Wave Decay Time From The Eccentricity Measurement Of Dynamically Captured Binaries, A. Vincent Paul, Parthapratim Mahapatra, Marc Favata, K. G. Arun
Department of Physics and Astronomy Faculty Scholarship and Creative Works
Dynamical capture in dense stellar environments is a promising channel for producing eccentric compact binary mergers. Although there have been no confident detections of eccentric mergers to date, a few candidates show indications of nonnegligible in-band eccentricity upon reanalysis of the data. By assuming an observed eccentric event originates from a dynamical gravitational-wave (GW) capture, we show that it is possible to identify the host environment using the eccentricity and mass posteriors. In particular, the eccentricity posterior can be mapped to posteriors on key capture parameters, such as the relative velocity at infinity and the impact parameter. By comparing these …
Reskilling And Retraining The Water Technology Workforce: An Agentic Generative Ai Framework For Water Purification, Nano‑Mems, And Curriculum Development, Satyadhar Joshi, Noor Zulfiqar
Reskilling And Retraining The Water Technology Workforce: An Agentic Generative Ai Framework For Water Purification, Nano‑Mems, And Curriculum Development, Satyadhar Joshi, Noor Zulfiqar
Harrisburg University Other Works
The rapid digitalization of water infrastructure is bringing artificial intelligence, advanced sensing, and membrane materials science into routine water treatment practice. At the same time, utilities, regulators, and training institutions face a persistent workforce challenge: many operators, engineers, and managers are being asked to adopt data-driven tools without a coherent educational pathway that links AI literacy to real treatment workflows. This article synthesizes recent literature on agentic generative AI, reinforcement learning, smart sensing, nano-enabled membranes, and digital twins for water systems, then translates those developments into a structured reskilling model for the water sector. The proposed framework is organized around …
Construct Overlap Inflates Apparent Economic-Capacity Alignment: Evidence From A Hebei City Panel, 2014–2023, Shuo Pang, Jianguang Hou, Danlin Yu
Construct Overlap Inflates Apparent Economic-Capacity Alignment: Evidence From A Hebei City Panel, 2014–2023, Shuo Pang, Jianguang Hou, Danlin Yu
Department of Earth and Environmental Studies Faculty Scholarship and Creative Works
Index-based urban sustainability studies often ask whether urban resilience and economic development evolve harmoniously, but the answer is unreliable when the two constructs contain the same economic indicators. A targeted audit of recent Chinese coupling studies shows that economic variables are commonly embedded in urban-resilience systems without a reported construct-overlap weight check. Using Hebei, China, as a measurement-validity test rather than as another provincial economic-growth case, this study analyzes a balanced 2014–2023 panel of 11 prefecture-level cities. Duplicated economic concepts account for 44.4% of the baseline resilience-index entropy weight and 88.2% of the baseline economic-index weight, indicating substantial mechanical exposure …
Oregon State Rank Assessment For Alpine Smelowskia (Smelowskia Ovalis), Lindsey K. Wise
Oregon State Rank Assessment For Alpine Smelowskia (Smelowskia Ovalis), Lindsey K. Wise
Institute for Natural Resources Publications
Oregon state conservation status assessment for Alpine smelowskia (Smelowskia ovalis) using NatureServe methodology, 2026.
Developing And Testing Visualization Simulations For The Gamma-Ray Energy Tracking Array (Greta), Blake Mcnulty
Developing And Testing Visualization Simulations For The Gamma-Ray Energy Tracking Array (Greta), Blake Mcnulty
Physics and Astronomy Summer Fellows
GRETA is a recently-completed Department of Energy-funded project to construct an array of 120 gamma-ray detectors for use in nuclear physics experiments. The Gretina Array was the successful pilot project to construct 48 of the eventual 120 detectors that would be used in the array. UCGretina is a program that is used to simulate the GRETA array for the purposes of planning experiments and analyzing measurements. My job for this summer, with the advent of the full GRETA system, was to implement the new modular mounting structure for the full GRETA array in the simulation code. This involves creating the …
History, Current Status, And Implications Of The Exploration And Exploitation Of Coal Resources In Guangxi, China, Wang Hui, Han Xiaozhong, Peng Zhilong, Li Huoying, Qin Baojian, Lu Ankang, Qin Xiaoyan, Peng Feifei, Xu Huiheng, Lan Bingui
History, Current Status, And Implications Of The Exploration And Exploitation Of Coal Resources In Guangxi, China, Wang Hui, Han Xiaozhong, Peng Zhilong, Li Huoying, Qin Baojian, Lu Ankang, Qin Xiaoyan, Peng Feifei, Xu Huiheng, Lan Bingui
Coal Geology & Exploration
Objective Based on a comprehensive review of the history and current status of coal exploration and exploitation, this study presents an analysis of both the endowment characteristics and the exploration and research levels of coal resources in Guangxi Zhuang Autonomous Region. From the perspective of coal self-sufficiency capacity and energy security guarantee, this study proposes several recommendations for the exploration and exploitation of coal resources in the region. Methods The exploration level, current status of exploitation, and supply-demand imbalance of coal resources in Guangxi are determined through a systematic literature review, surveys of coal mine enterprises, and exchanges with relevant …
Research And Practice Of Four-Dimensional In-Situ Stress Fields For Deep Coalbed Methane Production: A Case Study Of The Daning-Jixian Block, Ordos Basin, Wang Chengwang, Chen Yiyu, Gao Deli, Zhao Haifeng, Chen Gaojie
Research And Practice Of Four-Dimensional In-Situ Stress Fields For Deep Coalbed Methane Production: A Case Study Of The Daning-Jixian Block, Ordos Basin, Wang Chengwang, Chen Yiyu, Gao Deli, Zhao Haifeng, Chen Gaojie
Coal Geology & Exploration
Background Deep coalbed methane (CBM) reservoirs are characterized by well-developed microstructures and natural fractures, along with highly heterogeneous rock mechanical properties and in-situ stress field distribution. The CBM production of the reservoirs tends to cause constantly evolving formation pressure and in-situ stress within the control ranges of CBM wells, further enhancing the complexity of stress distribution. Additionally, severe fracturing channeling can be observed between new and old wells. This phenomenon is primarily triggered by in-situ stress variations induced by large-scale fracturing and CBM production. Therefore, accurately assessing the dynamic evolutionary patterns of in-situ stresses in reservoirs after fracturing and during …
Enrichment Mechanisms Of U And Th Elements In The Bauxite Rock Series Of The Benxi Formation, Lower Carboniferous, Central North China Block, Bian Yukang, Zhang Xiaoyang, Chen Jinfeng, Lyu Dawei, Zhu Dongya, Liu Quanyou, Meng Qingqiang, Shen Xiaoli, Li Qing, Kong Weijiang, Dou Yunfei
Enrichment Mechanisms Of U And Th Elements In The Bauxite Rock Series Of The Benxi Formation, Lower Carboniferous, Central North China Block, Bian Yukang, Zhang Xiaoyang, Chen Jinfeng, Lyu Dawei, Zhu Dongya, Liu Quanyou, Meng Qingqiang, Shen Xiaoli, Li Qing, Kong Weijiang, Dou Yunfei
Coal Geology & Exploration
Objective Uranium (U) and thorium (Th) in rocks and minerals are the material basis for the generation and release of crust-derived helium. Methods The enrichment characteristics and mechanisms of U and Th are key to understanding the accumulation of crust-derived helium reservoirs. Taking the bauxite series of the Benxi Formation in the central North China Block as the research object, this study reveals the enrichment mechanisms of U and Th in the bauxite series and calculates the helium generation rate by means of petrogeochemical and chronological research methods, combined with detrital zircon dating, sedimentary environment identification, and mass balance calculation. …
Sand Tank Experiments On The Seepage And Water Pressure Distribution During Single-Well Dewatering At The Bottom Of A Confined Aquifer, Wang Wenxue, Zhang Mengying, Li Yang, Fang Yuan, Zhao Shuli, Shen Mengjun
Sand Tank Experiments On The Seepage And Water Pressure Distribution During Single-Well Dewatering At The Bottom Of A Confined Aquifer, Wang Wenxue, Zhang Mengying, Li Yang, Fang Yuan, Zhao Shuli, Shen Mengjun
Coal Geology & Exploration
Background Depressurization through dewatering using inclined wells arranged at the aquifer bottom represents a crucial technical approach to the prevention and control of water-sand inrush disasters during coal mining beneath aquifers. However, the mechanisms underlying seepage-pressure interactions and water-preserved depressurization remain poorly understood. Methods Based on the water-yield properties of confined aquifers and the distribution characteristics of inclined wells for dewatering, this study developed a fan-shaped sand tank experimental system for simulating dewatering and seepage from confined aquifers. Using the experimental system, this study carried out seepage experiments using a partially penetrating well at the bottom of a confined aquifer …
Load Sharing Patterns And Their Key Influencing Factors For The Composite Structure Of A Lined Hard Rock Cavern For Compressed Air Energy Storage, Hu Lihua, Zhou Qiming, Zhang Kai, Yu Liyuan, Liang Xin, Sun Qiang, Wu Yun, Hu Chengguo, Li Wei
Load Sharing Patterns And Their Key Influencing Factors For The Composite Structure Of A Lined Hard Rock Cavern For Compressed Air Energy Storage, Hu Lihua, Zhou Qiming, Zhang Kai, Yu Liyuan, Liang Xin, Sun Qiang, Wu Yun, Hu Chengguo, Li Wei
Coal Geology & Exploration
Objective Compressed air energy storage (CAES) in a lined hard rock cavern holds great prospects. However, the load sharing mechanisms of the cavern’s composite structure, comprising a sealing layer, lining, and surrounding rocks, remain poorly understood.Methods Based on the elastic analytical solutions of stress fields, this first study derived the radial load equilibrium equations for the composite structure of a lined hard rock cavern for CAES. Accordingly, a novel method for calculating the load sharing ratios of the composite structure was developed. Then, an analysis scheme for the load sharing ratios was designed. Using this scheme, this study investigated …
Cnn-Based Assessment Of The Degrees Of Fracture Development In Bedrocks And Classification Of Bedrock Weathering Zones, Lei Jian, Lu Haifeng, Fan Yufei
Cnn-Based Assessment Of The Degrees Of Fracture Development In Bedrocks And Classification Of Bedrock Weathering Zones, Lei Jian, Lu Haifeng, Fan Yufei
Coal Geology & Exploration
Background Bedrock weathering zones exhibit distinct vertical gradational characteristics. Accurately identifying the degrees of fracture development in the zones is critical to the safe production of mines in shallowly buried coal seams covered by thick water-bearing unconsolidated layers. Methods Focusing on the Qinan coal mine in Anhui Province, this study proposed a hybrid convolutional neural network (CNN) model, which enabled feature extraction using a synergistic architecture consisting of conventional convolutional layers and inception modules. Specifically, based on conventional log data and calculated shale content and fracture development index, combined with core observations, this study constructed a dataset containing labels that …
Three-Dimensional, Collaborative Detection Approach For Fire Zones In Shallowly Buried Coal Seams And Its Application, Fan Kaixiang, Hu Xiangming, Hong Haibo, Dong Hao, Yu Shijian, Wei Zhengrong, Guo Yongxiang
Three-Dimensional, Collaborative Detection Approach For Fire Zones In Shallowly Buried Coal Seams And Its Application, Fan Kaixiang, Hu Xiangming, Hong Haibo, Dong Hao, Yu Shijian, Wei Zhengrong, Guo Yongxiang
Coal Geology & Exploration
Objective Fire zones in shallowly buried coal seams have long restricted safe and efficient coal mining due to their considerably hidden and hazardous nature. However, individual methods for fire source detection are susceptible to geological conditions and ambient noise, suffering from limited detection dimensions and the presence of technical blind spots. Therefore, they fail to accurately localize hidden fire sources in shallow coal seams. Methods This study proposes a three-dimensional, collaborative multi-source detection approach that combines the self-potential (SP) method, the radon measurement (Rn) method, electrical resistivity tomography (ERT; also referred to as high-density resistivity method), and the transient electromagnetic …
A Machine Learning Approach For Water Quality Assessment In The Lower Rio Grande Valley Watershed, Saika Nowshin Nowrin, Chu-Lin Cheng, Jungseok Ho, Jinwoo An, Fatemeh Nazari
A Machine Learning Approach For Water Quality Assessment In The Lower Rio Grande Valley Watershed, Saika Nowshin Nowrin, Chu-Lin Cheng, Jungseok Ho, Jinwoo An, Fatemeh Nazari
Civil Engineering Faculty Publications
Water quality analysis plays an essential role in maintaining the health and sustainability of river ecosystems, especially in semi-arid regions like the Arroyo Colorado Watershed in South Texas. Since the river is a vital source of water supply for local communities, agriculture, and wildlife, it faces significant challenges and pollution from land use changes, climate variation, and agricultural runoff. Continuous monitoring and assessment of water quality parameters and their temporal variability are essential to ensure the drinking water supply and aquatic ecosystem health. However, comprehensive laboratory-based water quality investigations are often constrained by higher costs, logistical complexity, and limited manpower. …
Evaluation Of Deep High-Quality Reservoirs Based On The Fuzzy Analytic Hierarchy Process And The Entropy Weight Method: A Case Study Of The No. 8 Coal Seam In The East-Central Ordos Basin, Yan Ronghui, Xu Hao, Hu Jianling, Li Xiaotian, Jiao Pengshuai, Huang Daojun, Chen Shida, Wu Xiaozhuo
Evaluation Of Deep High-Quality Reservoirs Based On The Fuzzy Analytic Hierarchy Process And The Entropy Weight Method: A Case Study Of The No. 8 Coal Seam In The East-Central Ordos Basin, Yan Ronghui, Xu Hao, Hu Jianling, Li Xiaotian, Jiao Pengshuai, Huang Daojun, Chen Shida, Wu Xiaozhuo
Coal Geology & Exploration
Objective Significant breakthroughs have been achieved in the exploration and exploitation of coalbed methane (CBM) in the deep No. 8 coal seam within the east-central Ordos Basin. However, a comprehensive quantitative evaluation system at the regional scale is yet to be established for reservoirs in the No. 8 coal seam. Methods Based on logs, coal quality, and measured physical property data from over 270 wells in the east-central Ordos Basin, this study developed a comprehensive evaluation system for deep coal reservoirs using the fuzzy analytic hierarchy process combined with the entropy weight method. Specifically, the evaluation system consisted of nine …
Co2 Fracturing Stimulation Technology For Low-Yield Directional Coalbed Methane Wells And Its Applications, Zhang Junsheng, Cao Yunxing, Wang Li, Wang Zhongbin, Yang Baige, Shi Bin, Cao Yongsen, Xu Fengyi
Co2 Fracturing Stimulation Technology For Low-Yield Directional Coalbed Methane Wells And Its Applications, Zhang Junsheng, Cao Yunxing, Wang Li, Wang Zhongbin, Yang Baige, Shi Bin, Cao Yongsen, Xu Fengyi
Coal Geology & Exploration
Background In China, low-yield coalbed methane (CBM) wells represent a high proportion of approximately 57% (over 12400 wells), generally encountering challenges such as low pressure, dry reservoirs, and near-wellbore formation damage and blockage. Conventional hydraulic fracturing is prone to induce water blocking damage, while treatments such as acidification offer only limited blockage-removing radii. Therefore, existing techniques are insufficient to achieve blockage removal and permeability enhancement while avoiding reservoir damage. Exploring efficient waterless stimulation technologies suitable for these low-yield wells is of great significance for increasing CBM production and advancing the CBM industry. Methods This study investigated directional wells PXC-03 and …
Water Hazards In Thick Floor Aquicludes For Coal Mining Above Confined Aquifers In North China-Type Coalfields: Patterns, Mechanisms, And Prevention And Control, Meng Haopeng, Yin Shangxian, Lian Huiqing, Yin Huichao, Hou Enke, Zhang Yi’An, Wang Zhuo, Jin Zidong, Cai Xiangjun, Cao Min, Wang Jianguang
Water Hazards In Thick Floor Aquicludes For Coal Mining Above Confined Aquifers In North China-Type Coalfields: Patterns, Mechanisms, And Prevention And Control, Meng Haopeng, Yin Shangxian, Lian Huiqing, Yin Huichao, Hou Enke, Zhang Yi’An, Wang Zhuo, Jin Zidong, Cai Xiangjun, Cao Min, Wang Jianguang
Coal Geology & Exploration
Background Water hazards in coal seam floors represent a core challenge restricting the exploitation of deep coal resources in North China-type coalfields. As coal mining extends to greater depths, previous studies and experience exhibit limited applicability in the pattern classification, mechanism interpretation, and prevention and control of water hazards in thick floor aquicludes. Therefore, there is an urgent need to make breakthroughs and improvements in these three aspects.Methods Using several methods, including case-based induction, theoretical analysis, numerical simulation, and technical summary, this study developed a classification system based on parallel multiple criteria for floor water hazards by combining available …
Assessing Fault-Induced Floor Water Inrushes Based On Improved Water Inrush Coefficients, Jiao Bin, Tan Wenfeng, Li Hongsheng, Chen Juntao, Gao Hongbing, Zhao Zizhang, Wu Fangcan
Assessing Fault-Induced Floor Water Inrushes Based On Improved Water Inrush Coefficients, Jiao Bin, Tan Wenfeng, Li Hongsheng, Chen Juntao, Gao Hongbing, Zhao Zizhang, Wu Fangcan
Coal Geology & Exploration
Background As coal mining in mines constantly expands to greater depths, water hazards in the Ordovician limestone aquifers of coal seam floors pose a serious threat to the mining of coal seams in lower formations. Fault reactivation represents a primary factor inducing water inrushes. However, the original water inrush coefficient (T = p/M) suffers from certain limitations when used to assess the water inrushes in areas with faults. Methods Four models of floor water inrushes induced by non-penetrating faults (i.e., concealed hydraulically conductive faults, concealed isolated faults, and exposed faults) and penetrating faults were constructed, and …
Numerical Simulations And Dispersion Analysis Of 3d In-Seam Waves Based On Finite Difference Method On Curvilinear Grids, Liu Dan, Ren Zhiming
Numerical Simulations And Dispersion Analysis Of 3d In-Seam Waves Based On Finite Difference Method On Curvilinear Grids, Liu Dan, Ren Zhiming
Coal Geology & Exploration
Background With the comprehensive advancement in intelligent coal mine construction, creating high-precision, transparent geological models of coal seams and their surrounding strata has emerged as a prerequisite for intelligent coal mining. The accurate identification of concealed geological anomalies, such as folds and faults, within coal seams represents a key challenge in safe coal mining. In-seam seismic exploration has become an important approach to detecting underground concealed structures owing to its advantages, including a considerable detection distance along coal seams, high precision, pronounced frequency dispersion effects, and facilitating the identification of waveform signatures. However, conventional methods for seam wave simulation are …
Table Of Contents, The Editors
Enhanced Adaptive Smith Predictor Control For Underground Coal Gasification With Long Time Delays, Tang Yang, Wu Qiong, Zhang Lei, Zhou Mingjun, Wan Min, Liao Zhuodong
Enhanced Adaptive Smith Predictor Control For Underground Coal Gasification With Long Time Delays, Tang Yang, Wu Qiong, Zhang Lei, Zhou Mingjun, Wan Min, Liao Zhuodong
Coal Geology & Exploration
Background Underground coal gasification (UCG) represents an in situ conversion technology used to convert solid coals into gaseous fuel. However, the reaction process during UCG exhibits significant time delays. Such a limitation will reduce the response capability of the UCG system and is prone to induce overshoot and oscillation, thereby increasing the system’s control difficulty and reducing its stability and dynamic performance. Method To address these issues, this study proposed an enhanced Smith predictor control algorithm based on a genetic algorithm and established a semi-physical experimental platform integrating a physical distributed control system DCS-Matlab for modeling. Using the platform, experiments …
Discovery And Implications For Ore Prospecting Of Gravitational Gliding Structures In The Lutang Coal-Based Graphite Mining Area, Hunan Province, China, Xiao Jincheng, Lu Jiang, Liu Zhiyu, Zhu Linying, Xiao Haibin, Li Long, Xiao Jing
Discovery And Implications For Ore Prospecting Of Gravitational Gliding Structures In The Lutang Coal-Based Graphite Mining Area, Hunan Province, China, Xiao Jincheng, Lu Jiang, Liu Zhiyu, Zhu Linying, Xiao Haibin, Li Long, Xiao Jing
Coal Geology & Exploration
Background Data from previous exploration and studies indicate that the Lutang coal-based graphite mining area in Hunan Province falls within the Lutang-Shatian synclinorium in terms of tectonic location, with coal-bearing strata dominated by the upper member of the Upper Permian Longtan Formation. Influenced by the intrusion of granites, coal seams adjacent to the Qitianling pluton on the eastern flank of the mining area have undergone contact metamorphism, forming coal-based graphite. Previous exploration results suggest that the Qitianling pluton has a maximum burial depth measured at an elevation of 0 m or less. However, with constant underground exposure in mines, previous …
Comparison Of Log-Based Coal Structure Identification Methods For Structurally Complex Areas: A Case Study Of The Huainan Mining Area, Zhang Zixin, Zhou Xiaozhi, Chen Xuehua
Comparison Of Log-Based Coal Structure Identification Methods For Structurally Complex Areas: A Case Study Of The Huainan Mining Area, Zhang Zixin, Zhou Xiaozhi, Chen Xuehua
Coal Geology & Exploration
Objective CO2 displacing coalbed methane (CBM) provides substantial environmental and energy benefits. However, differences in coal structures represent a key geological factor influencing the effectiveness of this technique. Constrained by the complex geological conditions for CBM occurrence and the impacts of multiple factors on the log responses of coal structures, traditional log-based methods for coal structure identification face challenges such as much human intervention, complex feature engineering, and poor adaptability. This study aims to achieve effective identification of complex coal structures within a single coal seam. Methods An asymmetric convolution kernel-based convolutional neural network (CNN) model for coal structure …