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Sustainability of Intensively Exploited Aquifer Systems in the North China Plain: Insights from Multiple Environmental Tracers 被引量:2
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作者 Aina Su Zongyu Chen +1 位作者 Jun Liu Wen Wei 《Journal of Earth Science》 SCIE CAS CSCD 2014年第3期605-611,共7页
Environmental tracers are proving to be a unique tool for assessing groundwater sustainability, such as characterization of recharge, identification of pathways and sources of contaminants, and prediction of groundwat... Environmental tracers are proving to be a unique tool for assessing groundwater sustainability, such as characterization of recharge, identification of pathways and sources of contaminants, and prediction of groundwater change in response to excessive abstraction. This paper helps to better understand the groundwater sustainability in the Quaternary aquifer from the tracer data in the North China Plain. Relatively modern ground waters occur in the piedmont plain with 3H-3He age less than 40 a within a depth 100 m. These ground waters are mainly recharged from the local precipitation and irrigation return. The recharge rate estimated by tracers is in the range of 0.24 to 0.32 m/a. Paleowater which is dated from 10 000 a B.P. to more than 35 000 a B.P. by radiocarbon dating is found in highly-confined portions of Quaternary aquifer systems. This indicates that water recharge took place during the past glacial period. The tracers have suggested a slow natural replenishment rates to the central plain. The aquifer has been overexploited currently. Some strategies that can be implemented to promote a sustainable groundwater supply are needed to implement in future. 展开更多
关键词 SUSTAINABILITY groundwater exploited environmental tracer North China Plain.
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Existence of Four Periodic Solutions of a Ratio-Dependent Predator-Prey Model with Exploited Terms 被引量:1
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作者 TIAN Desheng ZHANG Zhengqiu 《Wuhan University Journal of Natural Sciences》 CAS 2008年第1期1-5,共5页
We study a non-autonomous ratio-dependent predator-prey model with exploited terms. This model is of periodic coefficients, which incorporates the periodicity of the varying environment. By means of the coincidence de... We study a non-autonomous ratio-dependent predator-prey model with exploited terms. This model is of periodic coefficients, which incorporates the periodicity of the varying environment. By means of the coincidence degree theory, we establish sufficient conditions for the existence of at least four positive periodic solutions of this model. 展开更多
关键词 predator-prey model RATIO-DEPENDENT exploited term periodic solution coincidence degree
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Study on optimization of underlying coal bed exploited depth for tunnel
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作者 JIN Xiao-guang DING Bao-chen LI Xiao-hong 《Journal of Coal Science & Engineering(China)》 2010年第1期11-16,共6页
Combined with highway construction, the analysis on the relationship betweentunnel construction and coal resource exploitation was processed, which was based onthe research of rational exploitation depth of coal.3D FE... Combined with highway construction, the analysis on the relationship betweentunnel construction and coal resource exploitation was processed, which was based onthe research of rational exploitation depth of coal.3D FEM numerical analysis for tunnelexcavation was carried out according to engineering geological features of coal measurestrata in the project area.Based on the analysis of displacement and stress of the surroundingrock in the tunnel after excavation, the characteristics for displacement andstress of the tunnel support structure were analyzed when the underlying coal bed wasexploited with sublevel and full caving method.In addition, combined with the related codeand standard, the economic and safe prohibiting exploited depth of the underlying coalbed was proposed, so that a scientific basis for tunnel construction of coal measure strataand reasonable exploitation of the mineral resources in complex geological conditions canbe offered. 展开更多
关键词 deep buried tunnel underlying coal bed prohibiting exploited depth structura stability
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Threat Status of Commercially Exploited Trees in the Nigerian Rainforest
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作者 Francis E. Bisong Peter Buckley 《Open Journal of Forestry》 2014年第5期536-546,共11页
Unregulated commercial-scale exploitation of trees is an indication of the extent of threat to various tree species. The study examined the threat status of commercially exploited trees in the forest estates of South ... Unregulated commercial-scale exploitation of trees is an indication of the extent of threat to various tree species. The study examined the threat status of commercially exploited trees in the forest estates of South eastern Nigeria. Specifically, it identified tree species under threat, and categorized them into threat classes, as well as determined the rate at which exploited trees were slipping into extinction. The study utilized the IUCN’s threat categorization criteria, in determining the threat status of commercially exploited trees. This study combined both secondary and primary data sources generated through Forest Inventory records, Tree Felled Analysis records and Participatory Survey. Data such as population size and density of species, level of exploitation and threat sensitive social and ecological parameters were obtained and applied against the IUCN criteria. Twenty-eight (28) trees species representing Thirty-two percent (32%) of eighty-six (86) commercially exploited trees were identified as threatened, ranging from the Vulnerable to the Critically Endangered categories. The theory of small and declining population paradigms were found to be of relevance in explaining the processes. Nine tree species such as Triplochiton spp., Baillonella toxisperma, Pogaoleosa, Anopyxis spp. among others were considered to require urgent conservation attention. Recommendations are proposed to halt the process of decline in the biodiversity of exploited trees. 展开更多
关键词 Threat status Commercial IUCN exploited Trees ENDANGERED VULNERABLE THREATENED Species Extinction
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TWO BOHAI OILFIELDS TO BE EXPLOITED
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《China Oil & Gas》 CAS 1998年第1期31-31,共1页
关键词 BE TWO BOHAI OILFIELDS TO BE exploited
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Coalbed Reserves to be Exploited for New Energy
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作者 Du Ming,(China Uniled Coalbed Methane Co. , Ltd.) 《China Oil & Gas》 CAS 1996年第3期187-187,共1页
CoalbedReservestobeExploitedforNewEnergyDuMing,(ChinaUniledCoalbedMethaneCo.,Ltd.)ApprovedbytheStateCouncilo... CoalbedReservestobeExploitedforNewEnergyDuMing,(ChinaUniledCoalbedMethaneCo.,Ltd.)ApprovedbytheStateCouncilofChinainMarch1996... 展开更多
关键词 Coalbed Reserves to be exploited for New Energy
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Existence of at Least Two Periodic Solutions of a Ratio-dependent Predator-prey Model with Exploited Term 被引量:23
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作者 De-sheng Tian Xian-wu Zeng 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 2005年第3期489-494,共6页
In this paper, we study a non-autonomous ratio-dependent predator-prey model with exploited term. By means of the coincidence degree theory, we establish a sufficient condition for the existence of at least two positi... In this paper, we study a non-autonomous ratio-dependent predator-prey model with exploited term. By means of the coincidence degree theory, we establish a sufficient condition for the existence of at least two positive periodic solutions of this model. 展开更多
关键词 Predator-prey model RATIO-DEPENDENT exploited term periodic solution coincidence degree
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Multiple positive periodic solutions for a generalized delayed population model with an exploited term 被引量:1
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作者 Zheng-qiu ZHANG Zhi-cheng WANG 《Science China Mathematics》 SCIE 2007年第1期27-34,共8页
In this paper, the existence of two positive periodic solutions for a generalized delayed population model with an exploited term is established by using the continuation theorem of the coincidence degree theory.
关键词 two positive periodic solutions generalized delayed population model continuation theorem of coincidence degree theory exploited term 34K13
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Barber Optimization Algorithm:A New Human-Based Approach for Solving Optimization Problems
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作者 Tareq Hamadneh Belal Batiha +8 位作者 Omar Alsayyed Widi Aribowo Zeinab Montazeri Mohammad Dehghani Frank Werner Haider Ali Riyadh Kareem Jawad Ibraheem Kasim Ibraheem Kei Eguchi 《Computers, Materials & Continua》 2025年第5期2677-2718,共42页
In this study,a completely different approach to optimization is introduced through the development of a novel metaheuristic algorithm called the Barber Optimization Algorithm(BaOA).Inspired by the human interactions ... In this study,a completely different approach to optimization is introduced through the development of a novel metaheuristic algorithm called the Barber Optimization Algorithm(BaOA).Inspired by the human interactions between barbers and customers,BaOA captures two key processes:the customer’s selection of a hairstyle and the detailed refinement during the haircut.These processes are translated into a mathematical framework that forms the foundation of BaOA,consisting of two critical phases:exploration,representing the creative selection process,and exploitation,which focuses on refining details for optimization.The performance of BaOA is evaluated using 52 standard benchmark functions,including unimodal,high-dimensional multimodal,fixed-dimensional multimodal,and the Congress on Evolutionary Computation(CEC)2017 test suite.This comprehensive assessment highlights BaOA’s ability to balance exploration and exploitation effectively,resulting in high-quality solutions.A comparative analysis against twelve widely known metaheuristic algorithms further demonstrates BaOA’s superior performance,as it consistently delivers better results across most benchmark functions.To validate its real-world applicability,BaOA is tested on four engineering design problems,illustrating its capability to address practical challenges with remarkable efficiency.The results confirm BaOA’s versatility and reliability as an optimization tool.This study not only introduces an innovative algorithm but also establishes its effectiveness in solving complex problems,providing a foundation for future research and applications in diverse scientific and engineering domains. 展开更多
关键词 Optimization METAHEURISTIC barber HAIRSTYLE human-based algorithm exploration EXPLOITATION
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From Serfdom to Freedom
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作者 Li Nan 《China's Tibet》 2025年第3期10-14,共5页
Padma was 17 when the democratic reform was introduced in Xizang in 1959.Before the reform,the region had been ruled by feudal serfdom under a theocracy for centuries.Nearly one million serfs were subjected to estate-... Padma was 17 when the democratic reform was introduced in Xizang in 1959.Before the reform,the region had been ruled by feudal serfdom under a theocracy for centuries.Nearly one million serfs were subjected to estate-holders'cruel exploitation and oppression.Padma was one of them. 展开更多
关键词 SERFDOM democratic reform EXPLOITATION Xizang THEOCRACY FEUDALISM feudal serfdom FREEDOM
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Gender-based economic violence and the exploitation of women:A deep dive
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作者 Elif Sarac Deniz Odabas 《World Journal of Psychiatry》 2025年第3期58-65,共8页
Economic violence is a form of domestic violence that extends beyond physical harm,affecting victims’economic stability and independence.This situation perpetuates gender inequality and also reinforces the cycle of g... Economic violence is a form of domestic violence that extends beyond physical harm,affecting victims’economic stability and independence.This situation perpetuates gender inequality and also reinforces the cycle of gender-based violence.With definitions of economic violence broadening to encompass a range of coercive and manipulative behaviors-from financial abuse in domestic violence scenarios to the economic harassment faced by stay-at-home moms-understanding this form of exploitation is crucial for crafting effective interventions.This article aims to delve into various facets of economic violence,including its definition,prevalence,and the stark realities it creates for its victims.Following the search of international databases:Social Work Abstracts(EBSCO),Psychology Abstracts,Family and Women Studies Worldwide,Psychiatry Online,Psych INFO(including Psych ARTICLES),PubMed,Wiley,and Scopus,60 peer-reviewed articles that met all inclusion criteria were included in the paper.Our review clarifies that looking forward,the call for a comprehensive understanding of economic violence,enhanced legal frameworks,and the strengthening of supportive networks underscore the multidisciplinary approach required to combat this issue effectively. 展开更多
关键词 Gender based Domestic violence Economic violence EXPLOITATION WOMEN
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A Novel Approach Based on Recuperated Seed Search Optimization for Solving Mechanical Engineering Design Problems
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作者 Sumika Chauhan Govind Vashishtha +1 位作者 Riya Singh Divesh Bharti 《Computer Modeling in Engineering & Sciences》 2025年第7期309-343,共35页
This paper introduces a novel optimization approach called Recuperated Seed Search Optimization(RSSO),designed to address challenges in solving mechanical engineering design problems.Many optimization techniques strug... This paper introduces a novel optimization approach called Recuperated Seed Search Optimization(RSSO),designed to address challenges in solving mechanical engineering design problems.Many optimization techniques struggle with slow convergence and suboptimal solutions due to complex,nonlinear natures.The Sperm Swarm Optimization(SSO)algorithm,which mimics the sperm’s movement to reach an egg,is one such technique.To improve SSO,researchers combined it with three strategies:opposition-based learning(OBL),Cauchy mutation(CM),and position clamping.OBL introduces diversity to SSO by exploring opposite solutions,speeding up convergence.CM enhances both exploration and exploitation capabilities throughout the optimization process.This combined approach,RSSO,has been rigorously tested on standard benchmark functions,real-world engineering problems,and through statistical analysis(Wilcoxon test).The results demonstrate that RSSO significantly outperforms other optimization algorithms,achieving faster convergence and better solutions.The paper details the RSSO algorithm,discusses its implementation,and presents comparative results that validate its effectiveness in solving complex engineering design challenges. 展开更多
关键词 Local search Cauchy mutation opposition-based learning EXPLORATION EXPLOITATION
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Unveiling the dark side of leadership:How exploitative leadership undermines employees’work-related flow
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作者 Lingnan Kong Nuo Chen +1 位作者 Ruiqi Wang Shunkun Yu 《Journal of Psychology in Africa》 2025年第3期335-343,共9页
This study examined how exploitative leadership undermines employees’experience of flow with work role overload and traditionalist values.Data were collected from 361 staff members across diverse industries in China(... This study examined how exploitative leadership undermines employees’experience of flow with work role overload and traditionalist values.Data were collected from 361 staff members across diverse industries in China(females=58.17%,mean age=32.14,SD=5.83).Structural equation modeling results indicated that exploitative leadership reduces employees’work-related flow via increased role overload.Furthermore,employees’traditionality level moderates the exploitative leadership effects on role overload.Specifically,employees with higher traditionality reported lower role overload when experiencing exploitative leadership,suggesting that cultural values may buffer its negative impact.This study contributes to understanding the mechanism and contextual factors linking exploitative leadership to work-related flow,filling a gap in the literature.Organizations are encouraged to reduce exploitative leadership behaviors through leadership development programs and to consider employees’value orientations when designing work environments. 展开更多
关键词 exploitative leadership role overload work-related flow traditionality
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Patterns in Heuristic Optimization Algorithms: A Comprehensive Analysis
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作者 Robertas Damasevicius 《Computers, Materials & Continua》 2025年第2期1493-1538,共46页
Heuristic optimization algorithms have been widely used in solving complex optimization problems in various fields such as engineering,economics,and computer science.These algorithms are designed to find high-quality ... Heuristic optimization algorithms have been widely used in solving complex optimization problems in various fields such as engineering,economics,and computer science.These algorithms are designed to find high-quality solutions efficiently by balancing exploration of the search space and exploitation of promising solutions.While heuristic optimization algorithms vary in their specific details,they often exhibit common patterns that are essential to their effectiveness.This paper aims to analyze and explore common patterns in heuristic optimization algorithms.Through a comprehensive review of the literature,we identify the patterns that are commonly observed in these algorithms,including initialization,local search,diversity maintenance,adaptation,and stochasticity.For each pattern,we describe the motivation behind it,its implementation,and its impact on the search process.To demonstrate the utility of our analysis,we identify these patterns in multiple heuristic optimization algorithms.For each case study,we analyze how the patterns are implemented in the algorithm and how they contribute to its performance.Through these case studies,we show how our analysis can be used to understand the behavior of heuristic optimization algorithms and guide the design of new algorithms.Our analysis reveals that patterns in heuristic optimization algorithms are essential to their effectiveness.By understanding and incorporating these patterns into the design of new algorithms,researchers can develop more efficient and effective optimization algorithms. 展开更多
关键词 Heuristic optimization algorithms design patterns INITIALIZATION local search diversity maintenance ADAPTATION STOCHASTICITY exploration EXPLOITATION search space metaheuristics
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Linking proactive personality to strengths use: The mediator of psychological safety and the moderator of exploitative leadership
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作者 Wenyin Yang Zhijie Xu Yang Liu 《Journal of Psychology in Africa》 2025年第1期43-49,共7页
Drawing upon the Conservation of Resources theory,this study investigated the relationship between proactive personality and strengths use,as well as the mediating role of psychological safety and the moderating role ... Drawing upon the Conservation of Resources theory,this study investigated the relationship between proactive personality and strengths use,as well as the mediating role of psychological safety and the moderating role of exploitative leadership within this relationship.Data were collected from 368 employees(females=57.61%;mean age=32.35;SD=6.31)working in various organizations in China at two points in time with a two-week interval.We conducted structural equation modeling and a moderated mediation path analysis to test our hypotheses.The results demonstrated that proactive personality is positively related to strengths use and psychological safety partially mediates the association of proactive personality and strengths use.Furthermore,this study also found that exploitative leadership weakens the direct relationship between proactive personality and psychological safety and the indirect relationship of proactive personality with strengths use through psychological safety.This study identified the underlying mechanisms between proactive personality and strengths use. 展开更多
关键词 proactive personality psychological safety exploitative leadership strengths use
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A novel permeability calculation model to simultaneously quantify the impacts of pore and fracture with full feature size
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作者 Minghui Li Banghong Zhang +4 位作者 Zhouqian Wu Shaochen Luo Jun Lu Dongming Zhang Heping Xie 《International Journal of Mining Science and Technology》 2025年第4期609-618,共10页
The permeability of rocks is of utmost importance in the exploitation of deep geological resources.Current characterizations of rock permeability typically consider the influence of either pores or fractures alone.How... The permeability of rocks is of utmost importance in the exploitation of deep geological resources.Current characterizations of rock permeability typically consider the influence of either pores or fractures alone.However,deep reservoir rock formations are subjected to complex environments with coupling of high temperature and stress.As a result,deep reservoir rocks possess a complex structure comprising of pores and fractures,making it challenging to understand their impact on permeability.Comprehending this relationship is vital for the secure and efficient exploitation of deep geological resources.This study presents a permeability calculation model that enables simultaneously quantify the impacts of pore and fracture with full feature size.The model independently considers large-scale fractures’fractal properties and tortuosity while also addressing the distribution and size of small-scale pores.A tortuosity expression that incorporates the effects of thermal damage has been developed using the pore geometric elasticity method.Considering the distinct contributions of pores and fractures to rock permeability,a comprehensive rock permeability calculation model is established.This model has two main strengths:it thoroughly characterizes the influence of pore structures on permeability at multiple scales and precisely details how fractal attributes of fractures affect permeability.To validate the applicability of the model,this study conducted seepage experiments and microscopic observations,capturing the variations in permeability under thermo-mechanical coupling,while quantifying the geometric characteristics and spatial distribution of pores and fractures within the rock.By comparing the measured permeability results,the theoretical values demonstrated a commendable fit.In comparison to previous models,this innovative approach more accurately captures various flow characteristics of the rock under the influence of thermo-mechanical coupling. 展开更多
关键词 Hot dry rock Geothermal exploitation PERMEABILITY Fracture-pore microstructure
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Thermophysical-mechanical behaviors of hot dry granite subjected to thermal shock cycles and dynamic loadings
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作者 Ju Wang Feng Dai +2 位作者 Yi Liu Hao Tan Pan Zhou 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第9期5437-5452,共16页
Exploring dynamic mechanical responses and failure behaviors of hot dry rock(HDR)is significant for geothermal exploitation and stability assessment.In this study,via the split Hopkinson pressure bar(SHPB)system,a ser... Exploring dynamic mechanical responses and failure behaviors of hot dry rock(HDR)is significant for geothermal exploitation and stability assessment.In this study,via the split Hopkinson pressure bar(SHPB)system,a series of dynamic compression tests were conducted on granite treated by cyclic thermal shocks at different temperatures.We analyzed the effects of cyclic thermal shock on the thermal-related physical and dynamic mechanical behaviors of granite.Specifically,the P-wave velocity,dynamic strength,and elastic modulus of the tested granite decrease with increasing temperature and cycle number,while porosity and peak strain increase.The degradation law of dynamic mechanical properties could be described by a cubic polynomial.Cyclic thermal shock promotes shear cracks propagation,causing dynamic failure mode of granite to transition from splitting to tensile-shear composite failure,accompanied by surface spalling and debris splashing.Moreover,the thermal shock damage evolution and coupled failure mechanism of tested granite are discussed.The evolution of thermal shock damage with thermal shock cycle numbers shows an obvious S-shaped surface,featured by an exponential correlation with dynamic mechanical parameters.In addition,with increasing thermal shock temperature and cycles,granite mineral species barely change,but the length and width of thermal cracks increase significantly.The non-uniform expansion of minerals,thermal shock-induced cracking,and water-rock interaction are primary factors for deteriorating dynamic mechanical properties of granite under cyclic thermal shock. 展开更多
关键词 Geothermal exploitation Cyclic thermal shock GRANITE Thermal-related physical properties Dynamic mechanical behavior Failure mechanism
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Exploiting a No-Regret Opponent in Repeated Zero-Sum Games
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作者 LI Kai HUANG Wenhan +1 位作者 LI Chenchen DENG Xiaotie 《Journal of Shanghai Jiaotong university(Science)》 2025年第2期385-398,共14页
In repeated zero-sum games,instead of constantly playing an equilibrium strategy of the stage game,learning to exploit the opponent given historical interactions could typically obtain a higher utility.However,when pl... In repeated zero-sum games,instead of constantly playing an equilibrium strategy of the stage game,learning to exploit the opponent given historical interactions could typically obtain a higher utility.However,when playing against a fully adaptive opponent,one would have dificulty identifying the opponent's adaptive dynamics and further exploiting its potential weakness.In this paper,we study the problem of optimizing against the adaptive opponent who uses no-regret learning.No-regret learning is a classic and widely-used branch of adaptive learning algorithms.We propose a general framework for online modeling no-regret opponents and exploiting their weakness.With this framework,one could approximate the opponent's no-regret learning dynamics and then develop a response plan to obtain a significant profit based on the inferences of the opponent's strategies.We employ two system identification architectures,including the recurrent neural network(RNN)and the nonlinear autoregressive exogenous model,and adopt an efficient greedy response plan within the framework.Theoretically,we prove the approximation capability of our RNN architecture at approximating specific no-regret dynamics.Empirically,we demonstrate that during interactions at a low level of non-stationarity,our architectures could approximate the dynamics with a low error,and the derived policies could exploit the no-regret opponent to obtain a decent utility. 展开更多
关键词 no-regret learning repeated game opponent exploitation opponent modeling dynamical system system identification recurrent neural network(RNN)
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On Relevant Problems of Formulating a Comprehensive Interaction Theory for Nonlinear Geomechanical and Physicochemical Processes Within Rock Masses
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作者 KIRYAYEV Tatyana-alexeyevna 《辽宁大学学报(自然科学版)》 2025年第2期111-127,共17页
This study employs experimental and analytical methods to quantitatively investigate the nonlinear geomechanical and physicochemical processes of multiphase and high-stress coal-bearing rock masses and non-equilibrium... This study employs experimental and analytical methods to quantitatively investigate the nonlinear geomechanical and physicochemical processes of multiphase and high-stress coal-bearing rock masses and non-equilibrium geological materials,as well as their interactions.The research encompasses following aspects,i.e.1)the relationship between volatile matter yield,geological age,and distance from magmatic deposits in Kuzbass coalfield;2)the impact of physicochemical property bifurcations on coal and gas outbursts;3)the variation law of coalbed methane content with burial depth;4)the relaxation energy of gas content;5)the specific surface area of coal;6)the relationship between heat release and deformation waves of Kuzbass coal samples of different orders under uniaxial compression;7)the gas outbursts in different mines in Kuzbass;8)the relationship between seismic energy and gas outburst concentration in coal mines;9)the influence of piston mechanism;10)the connection operation between Langmuir equation and Oparin equation;and 11)the equation of motion for structural media.The research results have created a prerequisite for establishing a unified theory of the interaction between nonlinear geomechanics and physicochemical processes in rock masses,which is of great significance for the safe development and utilization of underground resources. 展开更多
关键词 mining engineering oil and gas reservoir exploitation volatile matter yield gas relaxation energy gas outburst
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