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中山大学学报（自然科学版） 2008年第5期47卷 23-27,36页

作者：杨洁郭先平北京信息科技大学理学院北京100192 中山大学数学与计算科学学院广东广州510275

讨论了赔付函数可能既无上界又无下界的离散时间可数状态非零和随机对策的折扣模型。在零和随机对策中常用的"漂移"和"连续-紧"性条件下,用Fan's不动点定理证明了Nash平衡点的存在性。

关键词：非零和随机对策期望折扣赔付准则 Nash平衡点可数状态空间

Borel状态空间非平稳MDP的平均方差准则

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数学学报（中文版） 2001年第2期44卷 333-342页

作者：郭先平中山大学数学系广东广州510275

本文考虑具有Ｂｏｒｅｌ状态空间和行动空间非平稳ＭＤＰ的平均方差准则．首先，在遍历条件下，利用最优方程，证明了关于平均期望目标最优马氏策略的存在性．然后，通过构造新的模型，利用马氏过程的理论，进一步证明了在关于平均期... 详细信息

本文考虑具有Ｂｏｒｅｌ状态空间和行动空间非平稳ＭＤＰ的平均方差准则．首先，在遍历条件下，利用最优方程，证明了关于平均期望目标最优马氏策略的存在性．然后，通过构造新的模型，利用马氏过程的理论，进一步证明了在关于平均期望目标是最优的一类马氏策略中，存在一个马氏策略使得平均方差达到最小．作为本文的特例还得到了ＤｙｎｋｉｎＥ．Ｂ．和ＹｕｓｈｋｅｖｉｃｈＡ．Ａ．及ＫｕｒａｎｏＭ．等中的主要结果．

关键词：非平衡MDP 平均方差目标最优方程最优马氏策略 Borel状态空间遍历条件马氏过程

The One-Dimensional Distribution and Construction of Semi-Markov Processes

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Journal of Mathematical Research and Exposition 2008年第3期28卷 617-627页

作者： TANG Rong guo xian ping LIU Zai Ming School of Mathematics and Computational Science Sun Yat-Sen University Guangdong 510275 China School of Mathematical Science and Computing Technology Central South University Hunan 410075 China

In this paper, we obtain the transition probability of jump chain of semi-Markov pro- cess, the distribution of sojourn time and one-dimensional distribution of semi-Markov process. Furthermore, the semi-Markov process X（t, ω） is constructed from the semi-Markov matrix and it is proved that two definitions of semi-Markov process are equivalent.

关键词： semi-Markov process Markov skeleton process sojourn time one-dimensionai distribution.

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受控排队系统的平均最优与约束平均最优

控制理论与应用 2009年第2期26卷 139-144页

作者：张兰兰郭先平南方医科大学公共卫生与热带医学学院广东广州510515 中山大学数学与计算科学学院广东广州510275

根据连续时间马尔可夫决策过程的平均准则,给出了一种特殊的马尔可夫决策过程—受控排队系统平均最优以及约束最优的新条件.这个新条件仅使用模型的初始数据,但利用了生灭过程的遍历性理论.可以证明受控排队系统存在平均最优平稳策略与... 详细信息

根据连续时间马尔可夫决策过程的平均准则,给出了一种特殊的马尔可夫决策过程—受控排队系统平均最优以及约束最优的新条件.这个新条件仅使用模型的初始数据,但利用了生灭过程的遍历性理论.可以证明受控排队系统存在平均最优平稳策略与约束平均最优策略.

关键词：连续时间马尔可夫决策过程平均准则受控排队系统平均最优平稳策略约束平均最优策略

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英语专业大学生如何注意和提取语块

解放军外国语学院学报 2011年第2期34卷 44-49,127-128页

作者：郭娴娉江苏技术师范学院外国语学院江苏常州213001

本研究采用测试和回溯性访谈方式,调查分析了大学生在阅读中注意语块、在翻译中提取语块的各种原因,以及学习和掌握语块对英语水平的影响。研究发现:1)在阅读中,学习者会有意识地注意他们认为重要、有用、值得学习的语块,且注意语块多... 详细信息

本研究采用测试和回溯性访谈方式,调查分析了大学生在阅读中注意语块、在翻译中提取语块的各种原因,以及学习和掌握语块对英语水平的影响。研究发现:1)在阅读中,学习者会有意识地注意他们认为重要、有用、值得学习的语块,且注意语块多少与英语水平密切相关;2)在翻译中,学习者能提取那些刻意背过、反复碰到、经常使用的语块,且使用语块的能力与英语水平有明显的相关性。

关键词：语块双模式体系语块意识

Ultrafast synthesis of Na3V2（PO4）3 cathode for high performance sodium-ion batteries

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Chinese Chemical Letters 2025年第2期36卷 564-567页

作者： Ruofan Yin Zhaoxin guo Rui Liu xian-Sen Tao School of Chemistry Chemical Engineering and Materials Jining University School of Materials Science and Engineering Shandong University of Science and Technology

Na3V2（PO4）3（NVP） is regarded as alternative cathode material for sodium-ion batteries（SIBs） due to its potential high-rate performance and pronounced long-term cycle stability. However, electronic conductivity and tap density are difficult to be balanced. Herein, we report that high-temperature shock（HTS） can prepare “single crystalline like” NVP which combines high-rate capability with high tap density together into one with the assistance of carbon framework and large particle. Thus, high reversible capacity of 110m Ah/g at 0.1 C with 89.9% capacity retention after 1600 cycles at 1 C and specific capacity of 83.5 m Ah/g at 50 C rate has been exhibited. This study provides a novel strategy to guide the production of high tap density, and rate performance polyanionic cathode materials.

关键词： Cathode materials Cycling stability High-temperature shock Na3V2(PO4)3 Sodium-ion batteries

Deep reinforcement learning based integrated evasion and impact hierarchical intelligent policy of exo-atmospheric vehicles

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Chinese Journal of Aeronautics 2025年第1期38卷 409-426页

作者： Leliang REN Weilin guo Yong xian Zhenyu LIU Daqiao ZHANG Shaopeng LI Xi’an Research Institute of High Technology Xi’an 710025China China Xi’an Satellite Control Center Xi’an710043China Department of Automation Tsinghua UniversityBeijing 100084China

Exo-atmospheric vehicles are constrained by limited maneuverability,which leads to the contradiction between evasive maneuver and precision *** address the problem of Integrated Evasion and Impact(IEI)decision under multi-constraint conditions,a hierarchical intelligent decision-making method based on Deep Reinforcement Learning(DRL)was ***,an intelligent decision-making framework of“DRL evasion decision”+“impact prediction guidance decision”was established:it takes the impact point deviation correction ability as the constraint and the maximum miss distance as the objective,and effectively solves the problem of poor decisionmaking effect caused by the large IEI decision ***,to solve the sparse reward problem faced by evasion decision-making,a hierarchical decision-making method consisting of maneuver timing decision and maneuver duration decision was proposed,and the corresponding Markov Decision Process(MDP)was designed.A detailed simulation experiment was designed to analyze the advantages and computational complexity of the proposed *** results show that the proposed model has good performance and low computational resource *** minimum miss distance is 21.3 m under the condition of guaranteeing the impact point accuracy,and the single decision-making time is 4.086 ms on an STM32F407 single-chip microcomputer,which has engineering application value.

关键词： Exo-atmospheric vehicle Integrated evasion and impact Deep reinforcement learning Hierarchical intelligent policy Single-chip microcomputer Miss distance

Evolution and generation mechanism of retained oil in lacustrine shales: A combined ReaxFF-MD and pyrolysis simulation perspective

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Petroleum Science 2025年第1期22卷 29-41页

作者： Biao Sun Xiao-ping Liu Jie Liu Tian Liu Zu-xian Hua Wen-Di Peng National Key Laboratory of Petroleum Resources and Engineering China University of Petroleum (Beijing) College of Geosciences China University of Petroleum (Beijing) International Petroleum Exploration and Production Corporation SINOPEC

To accurately investigate the evolution characteristics and generation mechanism of retained oil, the study analyzed organic-rich lacustrine shale samples from the Paleogene Kongdian Formation in Cangdong Sag, Bohai Bay Basin. This analysis involves Rock-Eval pyrolysis, pyrolysis simulation experiments,Gas Chromatograph Mass Spectrometer（GC-MS）, and reactive molecular dynamics simulations（Reax FF）. The results revealed the retained oil primarily consisted of n-alkanes with carbon numbers ranging from C14to C36. The generation of retained oil occurred through three stages. A slow growth stage of production rate was observed before reaching the peak of oil production in Stage I. Stage II involved a rapid increase in oil retention, with C12-C17and C24-C32serving as the primary components,increasing continuously during the pyrolysis process. The generation process involved the cleavage of weak bonds, including bridging bonds（hydroxyl, oxy, peroxy, imino, amino, and nitro）, ether bonds, and acid amides in the first stage（Ro= 0.50%-0.75%）. The carbon chains in aromatic ring structures with heteroatomic functional groups breaks in the second stage（Ro= 0.75%-1.20%）. In the third stage（Ro= 1.20%-2.50%）, the ring structures underwent ring-opening reactions to synthesize iso-short-chain olefins and radicals, while further breakdown of aliphatic chains occurred. By coupling pyrolysis simulation experiments and molecular simulation technology, the evolution characteristics and bond breaking mechanism of retained oil in three stages were revealed, providing a reference for the formation and evolution mechanism of retained oil.

关键词： Lacustrine shale Retained oiliness evolution Pyrolysis simulation experiments ReaxFF molecular dynamics Hydrocarbon generation evolution

Artificial intelligence advances drug delivery system and its clinical transition

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Science Bulletin 2025年第3期70卷 305-308页

作者： Hui Wang Xiao-Yan You guo-ping Zhao Master Lab for Innovative Application of Nature Products National Center of Technology Innovation for Synthetic BiologyTianjin Institute of Industrial BiotechnologyChinese Academy of Sciences(CAS)Tianjin 300308China Henan Engineering Research Center of Food Microbiology College of Food and BioengineeringHenan University of Science and TechnologyLuoyang 471023China Haihe Laboratory of Synthetic Biology Tianjin 300308China CAS-Key Laboratory of Synthetic Biology CAS Center for Excellence in Molecular Plant SciencesShanghai Institute of Plant Physiology and EcologyChinese Academy of SciencesShanghai 200032China CAS Key Laboratory of Quantitative Engineering Biology Shenzhen Institute of Synthetic BiologyShenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhen 518055China

Since November 2022,ChatGPT,an artificial intelligence(AI)chatbot,has rapidly captured global attention for its detailed responses and articulated answers across a broad spectrum of knowledge domains[1],[2].All industries will reorient around it,prompting a reevaluation of how this technology could further promote scientifical research and its clinical applications.

关键词： system transition spectrum

Constrained Networked Predictive Control for Nonlinear Systems Using a High-Order Fully Actuated System Approach

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IEEE/CAA Journal of Automatica Sinica 2025年第2期12卷 478-480页

作者： Yi Huang guo-ping Liu Yi Yu Wenshan Hu the School of Electrical Engineering and Automation Wuhan University IEEE the Center for Control Science and Technology Southern University of Science and Technology the Department of Electrical and Electronic Engineering The Hong Kong Polytechnic University

Dear Editor,In this letter, a constrained networked predictive control strategy is proposed for the optimal control problem of complex nonlinear highorder fully actuated (HOFA) systems with noises. The method can effectively deal with nonlinearities, constraints, and noises in the system, optimize the performance metric, and present an upper bound on the stable output of the system.

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