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控制方向未知的受限多智能体系统的预设时间模糊控制

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工程科学学报 2025年第1期47卷 121-129页

作者：李菲周超范利蓉王芳燕山大学理学院秦皇岛066004 河北农业大学海洋学院秦皇岛066003

综合考虑受控制方向未知、输入受限和状态时延影响的有领导者多智能体系统的编队控制问题,设计基于模糊逻辑系统的预设时间一致性控制策略.为了保证编队输出误差在预设时间内满足预定的约束范围要求,引入预设时间性能函数,构造Lyapunov-... 详细信息

综合考虑受控制方向未知、输入受限和状态时延影响的有领导者多智能体系统的编队控制问题,设计基于模糊逻辑系统的预设时间一致性控制策略.为了保证编队输出误差在预设时间内满足预定的约束范围要求,引入预设时间性能函数,构造Lyapunov-Krasovskii(L-K)泛函解决状态时延问题,将外界干扰和L-K泛函的导数中的部分项定义为未知非线性函数,并利用模糊逻辑系统对其进行估计,利用Nussbaum函数和均值定理分别处理控制方向未知和输入受限问题,基于以上设计,提出预设时间模糊控制策略,并通过Lyapunov稳定性理论,分析闭环系统的有界稳定性,数值对比仿真和两级化学反应器应用仿真说明控制方法的有效性.

关键词：多智能体系统状态时延输出误差约束输入受限控制方向未知

使用合规农药能确保农产品“地头”质量安全吗?——基于豇豆农户的扎根理论分析

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海南大学学报（人文社会科学版） 2025年第1期43卷 119-128页

作者：樊孝凤张娇朱月季海南大学国际商学院海南海口570228

新的农产品质量安全法首次将小农户施药行为纳入监管范围,进一步厘清农户施药行为的影响机理与因素,有助于政府精准施策。通过对海南3个村32户农民豇豆种植过程的全程蹲点跟踪,对豇豆施药环节的参与式观察与深度访谈,运用扎根理论分析... 详细信息

新的农产品质量安全法首次将小农户施药行为纳入监管范围,进一步厘清农户施药行为的影响机理与因素,有助于政府精准施策。通过对海南3个村32户农民豇豆种植过程的全程蹲点跟踪,对豇豆施药环节的参与式观察与深度访谈,运用扎根理论分析了访谈资料。研究发现:农户施药环节是一个复杂的行为选择过程,即使施用合规农药也不能确保农产品在产地的质量安全。在合规农药视角下影响农户施药行为选择的最重要因素是信息渠道,其次是农产品质量安全管理的政策强度、农产品市场价格和农村劳动用工成本。同时,邻里效应在农户施药行为选择中的作用越来越弱。在此基础上提出,要增加农户用药信息的有效供给渠道,加强农产品质量安全的全面检测,坚持为农户提供形式多样的有针对性的有效培训,增加重要食用农产品质量安全关键技术供给与推广,加强农产品“优质优价”市场建设的政策建议,并进一步指出海南自贸港建设和RECP协议实施背景下提升海南农产品质量安全水平的紧迫性。

关键词：合规农药施药行为农产品质量安全扎根理论

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Mechanical Properties of a Low-thermal-expansion Aluminum/silicon Composite Produced by Powder Metallurgy

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journal of Materials science & Technology 2014年第4期30卷 417-422页

作者： Y.Q.Liu s.H.Wei j.Z.fan Z.L.Ma T.Zuo National Engineering & Technology Research Center for Nonferrous Metal Matrix Composites Beijing General Research Institute for Nonferrous Metals

AI matrix composite containing high volume fraction silicon has been promising candidate for lightweight and low-thermal-expansion components. Whereas, optimization of its mechanical properties still is an open challenge. In this article, a flexile powder metallurgy processing was used to produce a fully dense AI-4.0Cu （wt%） alloy composite reinforced with 65 vol.% si particles. In this composite, si particles were homogenously distributed, and the particle size was refined to the range of 3-15 μm. Tensile and flexural strength of the composite were 282 and 455 MPa, respectively, about 100% and 50% higher than the best properties reported in literature. The measured fracture toughness of the composite was 4.90 MPa m1/2. The improved strength of 65%si/AI was attributed to the optimized particle characteristics and matrix properties. This investigation is expected to provide a primary understanding of the mechanical behaviors of si/AI composites, and also promote the structural applications of this low-thermal-expansion material.

关键词： Aluminum matrix composite Powder metallurgy Mechanical properties Coefficient of thermal expansion Fracture

ChatGPT影响民主的技术逻辑、研判分析及应对策略

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海南大学学报（人文社会科学版） 2025年第1期43卷 76-85页

作者：王宝贵范鹏施韶亭兰州大学马克思主义学院甘肃兰州730000 甘肃省计算中心甘肃兰州730030

ChatGPT的持续爆火再次引起人们对人工智能影响问题的普遍关注。系统研究和评估ChatGPT对民主的影响具有理论和现实的双重意义。ChatGPT是人工智能技术发展新的里程碑,同样是一把双刃剑,其技术扩散嵌入政治领域是影响民主的逻辑起点。Ch... 详细信息

ChatGPT的持续爆火再次引起人们对人工智能影响问题的普遍关注。系统研究和评估ChatGPT对民主的影响具有理论和现实的双重意义。ChatGPT是人工智能技术发展新的里程碑,同样是一把双刃剑,其技术扩散嵌入政治领域是影响民主的逻辑起点。ChatGPT既有民主共治、共享、共商、共建的机遇和潜能,也有民主困境、失效、危机、异化、治理和话语权的挑战与风险。ChatGPT通过技术操控侵蚀民主、影响西方民主实施过程,通过话术游说影响民主决策及立法公正性,通过加深数字鸿沟削弱民主治理能力,通过话语权垄断维护西式民主话语霸权。我国要抓住机遇、迎接挑战,在价值设计、政党治理、社会治理、技术治理、素养提升等多个层面,建立和完善针对性的新型多元民主治理体系,用最新科技武装全过程人民民主的实践。

关键词： ChatGPT 民主人工智能技术逻辑

脂质转移蛋白siLTP1基因参与谷子耐盐响应初探

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作物学报 2025年第1期51卷 58-67页

作者：孟凡花刘敏沈傲刘炜山东省农业科学院农作物种质资源研究所山东济南250100 上海应用技术大学生态技术与工程学院上海201418

土壤盐渍化严重制约农业生产发展,通过提高植物耐盐性进行盐碱地综合利用,对于保障粮食安全,提升农业生产效率具有重要意义。脂质转移蛋白是一类在高等植物中广泛存在的小分子蛋白质,能够参与植株生长、信号转导以及多种生物和非生物胁... 详细信息

土壤盐渍化严重制约农业生产发展,通过提高植物耐盐性进行盐碱地综合利用,对于保障粮食安全,提升农业生产效率具有重要意义。脂质转移蛋白是一类在高等植物中广泛存在的小分子蛋白质,能够参与植株生长、信号转导以及多种生物和非生物胁迫过程。前期本课题组克隆到一个谷子中编码脂质转移蛋白的基因siLTP1,本研究通过构建其原核表达载体和植物双元过表达载体,获得了该基因的原核表达蛋白及同源转化过表达阳性植株,经进一步筛选获得4个纯合株系。体外耐盐性试验显示, siLTP1的原核表达蛋白具有一定耐盐性;转基因植株苗期耐盐生理指标测定显示,siLTP1过表达植株在遭受盐胁迫时,植株体内MDA积累减少,抗氧化酶含量升高,可积累更少的过氧化氢,从而降低胁迫对植株的氧化损伤,显示基因过表达植株具有更好的耐盐性。本研究结果初步揭示, siLTP1可正向调控谷子的耐盐性,其在谷子耐盐抗逆方面具有潜在功能,为耐盐谷子品种改良及新品种培育提供了理论基础和候选基因资源。

关键词：脂质转移蛋白 siLTP1 盐胁迫谷子耐盐响应

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Dividend or No Dividend in Delegated Blockchain Governance:A Game Theoretic Analysis

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journal of systems science and systems Engineering 2021年第3期30卷 288-306页

作者： Dapeng Pan j.Leon Zhao shaokun fan Ziqiong Zhang school of Management Harbin Institute of TechnologyHarbin150001China school of Management and Economics The Chinese University of Hong Kong(Shenzhen)Shenzhen518172China College of Business Oregon State University488 Austin HallCorvallisOR9733USA

Delegated blockchain governance is the frontier of blockchain design issues that is to improve the scalability of blockchain *** proof of stake(DPos)blockchains such as EOs must select a few super nodes for transaction *** particular,the blockchain community has debated recently on whether dividend should be allowed when electing super nodes,which might be considered as unethical or unfair,leading to an open research topic and a new research gap that has theoretical value for both academia and *** this paper,we build a theoretical framework to study how dividend affects user decisions and welfare in a DPos *** on game theory,we propose a three-player Hotelling model with two policies to study the behaviors of voters and *** first use a static game analysis to show that the benefits of dividend for voters and for candidates vary with the size of reward and there exists an interval,in which the zero dividend policy would be good for the welfare of both candidates and ***,we use an evolutionary game analysis to examine the process dynamics of super node selection,we find that the campaign strategy of candidates has to do with the size of platform reward given to the candidates by the blockchain *** in the asymmetric case,we find that higher level of platform reward turns to benefit candidates with large number of votes even *** findings are instrumental for designing dividend policies in DPos blockchains and can stimulate more potential research in blockchain governance.

关键词： Delegated proof of stake consensus algorithm blockchain Hotelling model evolutionary game

Creep-fatigue lives prediction and sensitivity study of 316H at 550 ℃

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Acta Metallurgica sinica(English Letters) 2011年第2期24卷 132-140页

作者： Zhichao fan David j smith Xuedong CHEN Mike W spindler Hefei General Machinery Research Institute Hefei 23-0031 China University of Bristol Bristol BS8 1TR UK British Energy Gloucester GL4 3RS UK

In Volume 2/3 of R5 ＂An assessment procedure for the high temperature response of structures＂, the strain based ductility exhaustion method is suggested to calculate the creep damage of stress concentration region, which involves description of creep dwell initial stress, stress drop and creep ductility. Considering lots of uncertainty existed in these assessment, some sensitivity analysis is required in R5 procedure to ensure the conservatism of assessment results. In this paper, laboratory creep-fatigue test data of 316H at 550 ℃ with different loading conditions are selected as a special case to investigate whether the basic R5 approach is conservative, and the different material data combinations of cyclic stress-strain, creep deformation and creep ductility are used to identify those significant parameters affecting the assessment results. The analytical results indicate that the creep deformation model and creep ductility data are more significant to the results comparing with cyclic stress-strain data. If the upper bound of creep deformation law and lower bound of creep ductility data are used to predict their creep-fatigue lives, the degree of conservatism can be as large as a factor of -300, but if the modified creep deformation model and cast specific ductility data are used, very well prediction results can be gained within a factor of ±2.0 although there is slight non-conservatism.

关键词： Creep Fatigue Damage Life prediction sensitivity study

The value of postoperative hepatic regional chemotherapy in prevention of recurrence after radical resection of primary liver cancer

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World journal of Gastroenterology 2000年第1期6卷 131-133页

作者： Wu ZQ fan j Qiu sj Zhou j Tang ZY Liver Cancer Institute Shanghai Medical UnviersityShanghai 200032China

INTRODUCTIONIn China,primary liver cancer (PLC) ranks secondin cancer mortality since the *** the field ofPLC treatment,surgical resection remains the best,which includes large PLC resection,small PLCresection,re-rese... 详细信息

关键词： subject headings liver neoplasms/drug therapy neoplasm recurrence/prevention and control regional chemotherapy

Multi-label Image Classification via Coarse-to-Fine Attention

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Chinese journal of Electronics 2019年第6期28卷 1118-1126页

作者： LYU fan LI Linyan Victor s.sheng FU Qiming HU Fuyuan school of Electronic and Information Engineering Suzhou University of Science and Technology College of Intelligence and Computing Tianjin University suzhou Institute of Trade and Commerce Department of Computer science Texas Tech University

Great efforts have been made by using deep neural networks to recognize multi-label *** multi-label image classification is very complicated,many studies seek to use the attention mechanism as a kind of guidance. Conventional attention-based methods always analyzed images directly and aggressively, which is difficult to well understand complicated scenes. We propose a global/local attention method that can recognize a multi-label image from coarse to fine by mimicking how human-beings observe images. Our global/local attention method first concentrates on the whole image, and then focuses on its local specific objects. We also propose a joint max-margin objective function, which enforces that the minimum score of positive labels should be larger than the maximum score of negative labels horizontally and vertically. This function further improve our multi-label image classification method. We evaluate the effectiveness of our method on two popular multi-label image datasets(i.e., Pascal VOC and Ms-COCO). Our experimental results show that our method outperforms state-of-the-art methods.

关键词： Multi-label classification Convolutional neural network Recurrent neural network Attention