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F-generation law and recognition of system law 被引量:4
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作者 Shi Kaiquan Yao Bingxue 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2007年第4期764-768,共5页
If a system is not disturbed (or invaded) by some law, there is no doubt that each system will move according to the expected law and keep stable. Although such a fact often appears, some unknown law breaks into the... If a system is not disturbed (or invaded) by some law, there is no doubt that each system will move according to the expected law and keep stable. Although such a fact often appears, some unknown law breaks into the system and leads it into turbulence. Using function one direction S-rough sets, this article gives the concept of the F-generation law in the system, the generation model of the F-generation law and the recognition method of the system law. Function one direction singular rough sets is a new theory and method in recognizing the disturbance law existing in the system and recognizing the system law. 展开更多
关键词 function one direction S-rough sets F-generation law recognition of system law recognition criterion APPLICATION
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Conservation laws for Birkhoffian systems of Herglotz type 被引量:5
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作者 Yi Zhang Xue Tian 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第9期223-229,共7页
Conservation laws for the Birkhoffian system and the constrained Birkhoffian system of Herglotz type are studied. We propose a new differential variational principle, called the Pfaff-Birkhoff-d'Alembert principle of... Conservation laws for the Birkhoffian system and the constrained Birkhoffian system of Herglotz type are studied. We propose a new differential variational principle, called the Pfaff-Birkhoff-d'Alembert principle of Herglotz type. Birkhoff's equations for both the Birkhoffian system and the constrained Birkhoffian system of Herglotz type are obtained. According to the relationship between the isochronal variation and the nonisochronal variation, the conditions of the invariance for the Pfaff-Birkhoff-d'Alembert principle of Herglotz type are given. Then, the conserved quantities for the Birkhoffian system and the constrained Birkhoffian system of Herglotz type are deduced. Furthermore, the inverse theorems of the conservation theorems are also established. 展开更多
关键词 Birkhoffian system conversation law differential variational principle variational problem of Herglotz type
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Approximation law for discrete-time variable structure control systems 被引量:6
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作者 Yan ZHENG Yuanwei JING 《控制理论与应用(英文版)》 EI 2006年第3期291-296,共6页
Two approximation laws of sliding mode for discrete-time variable structure control systems are proposed to overcome the limitations of the exponential approximation law and the variable rate approximation law. By app... Two approximation laws of sliding mode for discrete-time variable structure control systems are proposed to overcome the limitations of the exponential approximation law and the variable rate approximation law. By applying the proposed approximation laws of sliding mode to discrete-time variable structure control systems, the stability of origin can be guaranteed, and the chattering along the switching surface caused by discrete-time variable structure control can be restrained effectively. In designing of approximation laws, the problem that the system control input is restricted is also considered, which is very important in practical systems. Finally a simulation example shows the effectiveness of the two approximation laws proposed. 展开更多
关键词 Discrete-time systems Approximation law Variable structure control (VSC) Quasi-sliding mode CHATTERING
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SBV REGULARITY OF GENUINELY NONLINEAR HYPERBOLIC SYSTEMS OF CONSERVATION LAWS IN ONE SPACE DIMENSION 被引量:1
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作者 Stefano Bianchini 《Acta Mathematica Scientia》 SCIE CSCD 2012年第1期380-388,共9页
The problem of the presence of Cantor part in the derivative of a solution to a hyperbolic system of conservation laws is considered. An overview of the techniques involved in the proof is given, and a collection of r... The problem of the presence of Cantor part in the derivative of a solution to a hyperbolic system of conservation laws is considered. An overview of the techniques involved in the proof is given, and a collection of related problems concludes the paper. 展开更多
关键词 hyperbolic systems conservation laws SBV REGULARITY
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Application of a fourth-order relaxation scheme to hyperbolic systems of conservation laws 被引量:7
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作者 Jianzhong Chen Zhongke Shi 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2006年第1期84-92,共9页
A fourth-order relaxation scheme is derived and applied to hyperbolic systems of conservation laws in one and two space dimensions. The scheme is based on a fourthorder central weighted essentially nonoscillatory (CW... A fourth-order relaxation scheme is derived and applied to hyperbolic systems of conservation laws in one and two space dimensions. The scheme is based on a fourthorder central weighted essentially nonoscillatory (CWENO) reconstruction for one-dimensional cases, which is generalized to two-dimensional cases by the dimension-by-dimension approach. The large stability domain Runge-Kutta-type solver ROCK4 is used for time integration. The resulting method requires neither the use of Riemann solvers nor the computation of Jacobians and therefore it enjoys the main advantage of the relaxation schemes. The high accuracy and high-resolution properties of the present method are demonstrated in one- and two-dimensional numerical experiments. 展开更多
关键词 Hyperbolic systems of conservation laws Relaxation schemes CWENO reconstruction
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Division of Gas Accumulation System and Laws Controlling Distribution of Natural Gas in Typical Petroliferous Basins of China
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作者 Jiang Zhenxue Pang Xiongqi Jin Zhijun Chen Dongxia Basin & Reservoir Research Center, University of Petroleum, Beijing 102249 Key Laboratory of Hydrocarbon Accumulation, Ministry of Education, Beijing 102249 《Journal of China University of Geosciences》 SCIE CSCD 2002年第4期306-312,共7页
Considering the existing problems of the petroleum system, this paper bringsforward the concept of natural gas accumulation system and presents the dividing principles. Thendetailed statistics on the accumulation fact... Considering the existing problems of the petroleum system, this paper bringsforward the concept of natural gas accumulation system and presents the dividing principles. Thendetailed statistics on the accumulation factors of the 32 typical natural gas accumulation systemsin China and studies on the laws controlling distribution of gas are collected. The research showsthat the petroleum accumulation system is the basic unit controlling petroleum generation, migrationand accumulation. Generating intensity, generating amount, accumulating efficiency and migrationdistance plays an important role in the distribution of natural gas. Through analysis on results ofresources evaluation, discovered reserves and residual reserves, potential areas in middle-scaledpetroliferous basins in China are forecasted in this paper. Ordos, Sichuan, Tarim and Qaidam basinsare found out to be the main basins developing and enriching gas accumulation systems. 展开更多
关键词 petroliferous basins in china gas accumulation system petroleum system laws controlling gas potential area
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THE CONSERVATION LAW OF SECOND-ORDER NON-HOLONOMIC SYSTEM OF NON-CHETAEV'S TYPE
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作者 方建会 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2000年第7期836-840,共5页
The conservation law of second_order nonholonomic system of non_Chetaev's type was studied by means of the Jourdain's principle. The invariant condition of Jourdain's principle under infinitesi... The conservation law of second_order nonholonomic system of non_Chetaev's type was studied by means of the Jourdain's principle. The invariant condition of Jourdain's principle under infinitesimal transformation is given by introducing Jourdain's generators. Then the conservation law of the system is obtained under certain conditions. Finally a calculating example is given. 展开更多
关键词 Jourdain's principle nonholonomic system conservation law
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THE CONSERVATION LAW OF NONHOLONOMIC SYSTEM OF SECOND-ORDER NON-CHETAVE'S TYPE IN EVENT SPACE
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作者 FANG Jian-hui(方建会) 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2002年第1期89-94,共6页
The conservation law of nonholonomic system of second-order non-Chataev's type in event space is studied The Jourdain's principle in event space is presented. The invariant condition of the Jourdain's prin... The conservation law of nonholonomic system of second-order non-Chataev's type in event space is studied The Jourdain's principle in event space is presented. The invariant condition of the Jourdain's principle under infinitesimal transformation is given by introducing Jourdain's generators in event space. Then the conservation law of the system in event space is obtained under certain conditions. Finally a calculating example is given. 展开更多
关键词 event space Jourdain's principle nonholonomic system conservation law
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Study on Guidance Law of UAV Net Recovery System
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作者 张怡 赵少松 +1 位作者 王永生 张玉琢 《Defence Technology(防务技术)》 SCIE EI CAS 2007年第1期64-67,共4页
The design and realization of a net recovery system is introduced, which can recover UAV (unmanned aerial vehicle) reliably and safely. The mathematical model is built, and the horizontal and vertical guidance law is ... The design and realization of a net recovery system is introduced, which can recover UAV (unmanned aerial vehicle) reliably and safely. The mathematical model is built, and the horizontal and vertical guidance law is studied based on the aerodynamic parameters and actual flying trial data of a certain UAV. The simulation result shows that this system can realize the recovery safely, stably and accurately. 展开更多
关键词 无人飞行器 立网回收系统 制导律 模拟 气动力学
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A System Status Definition to Improve Behavior Description in Specifications Based on Constructal Law
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作者 Luciano Ondir Freire Dr. Delvonei Alves de Andrade Daniel Monterrain 《Open Journal of Applied Sciences》 2018年第8期315-337,共23页
System behavior description using states faces problems like state explosion, lack of clear definition of state, state identification and coordination between multiple agents. The goals of this work are to ease design... System behavior description using states faces problems like state explosion, lack of clear definition of state, state identification and coordination between multiple agents. The goals of this work are to ease design activity, to reduce engineering efforts, and to mitigate project risks. The proposed way is to improve information flow during design by adding definitions and some protocols or rules for communicating a specification or design description. This work presented an objective definition of system status (way of interaction with the rest of the world) along other concepts. This work focused in definitions as mind entities and their importance to rationalize work and mitigate project risks during design. This article presented some simple examples to illustrate the advantages of each aspect of proposed definition of system status and discussed limits and exceptions for such definition. The key finding was the proposed definition which was the simplest while keeping completeness at a given product breakdown level. Such definition of status enforced formal segregation of needs and solutions, and eased the inclusion of behavior definition in specifications. 展开更多
关键词 CYBER systems system Design CONSTRUCTAL law system Behavior Modelling State Analysis system Engineering
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A nonlinear discrete integrable coupling system and its infinite conservation laws
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作者 于发军 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第11期20-25,共6页
We construct a nonlinear integrable coupling of discrete soliton hierarchy, and establish the infinite conservation laws (CLs) for the nonlinear integrable coupling of the lattice hierarchy. As an explicit applicati... We construct a nonlinear integrable coupling of discrete soliton hierarchy, and establish the infinite conservation laws (CLs) for the nonlinear integrable coupling of the lattice hierarchy. As an explicit application of the method proposed in the paper, the infinite conservation laws of the nonlinear integrable coupling of the Volterra lattice hierarchy are presented. 展开更多
关键词 nonlinear integrable coupling system infinite conservation law Volterra lattice hierarchy
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Entropy Analysis of Vapor-Compression Refrigeration System by Using the Second Law of Thermodynamics
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作者 杨洪海 《Journal of China Textile University(English Edition)》 EI CAS 1999年第4期42-44,共3页
By means of the Second Law of Thermodynamics,thispaper gives out the entropy analysis method for vapor-comperession refrigeration system.The thermal irrevers-ibility of the system charged with R12 and its hopeful al-t... By means of the Second Law of Thermodynamics,thispaper gives out the entropy analysis method for vapor-comperession refrigeration system.The thermal irrevers-ibility of the system charged with R12 and its hopeful al-ternative refrlgerant R134a have been studied respective-ly.On the basis of all the research results of this paper,the measure used to save energy for vapor-compressionrefrigeration system has been put out. 展开更多
关键词 Vapor - Compression REFRIGERATION system Sec-ond law of THERMODYNAMICS ENTROPY ANALYSIS Alternative REFRIGERANT of CFC’s
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Weak Noether symmetry and conserved laws of Birkhoffian systems
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作者 解加芳 吴润衡 +2 位作者 张竺 邹杰涛 李国富 《Journal of Beijing Institute of Technology》 EI CAS 2012年第1期8-12,共5页
A new kind of weak Noether symmetry is obtained that arises in the study of Birkhoffian systems. The conserved quantities, which includes Noether conserved quantity, Hojman type conserved quantity and new type conserv... A new kind of weak Noether symmetry is obtained that arises in the study of Birkhoffian systems. The conserved quantities, which includes Noether conserved quantity, Hojman type conserved quantity and new type conserved quantity, are also calculated from this symmetry. Finally, two examples are presented to illustrated the application of these new results. 展开更多
关键词 Birkhoffian system weak Noether symmetry conserved laws
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Law Absence and System Construction of Equal Material Assistance Rights of Farmers in China
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作者 DIAO Qian-he School of Law,Henan Normal University,Xinxiang 453007,China 《Asian Agricultural Research》 2011年第3期57-60,共4页
Firstly,conception of farmers' equal material assistance rights is introduced from the aspects of equal rights,material assistance rights,and farmers' equal material assistance rights.Value function of farmers... Firstly,conception of farmers' equal material assistance rights is introduced from the aspects of equal rights,material assistance rights,and farmers' equal material assistance rights.Value function of farmers' equal material assistance rights is pointed out,which can eliminate the partial policies with urban priority orientation.It is a necessary condition for maintaining the legal and institutional authority,as well as an inevitable choice to realize the social justice and harmony.Current status of the law absence of farmers' equal material assistance rights in China is introduced,which is reflected in the lack of theoretical research on farmers' equal material assistance rights in the law circle,the lack of procedural legal system of farmers' equal material assistance rights at present,and the lack of actual law effectiveness of farmers' equal material assistance rights at present.System construction is a turning point to change the law absence of farmers' material assistance rights.Government should promote the economic development,provide material bases for the system construction of farmers' material assistance rights,enhance the legal consciousness of farmers,cultivate the ability of farmers to participate in equal material assistance rights,strengthen the procedural legislation and judicial justice,and ensure the farmers' material assistance rights. 展开更多
关键词 FARMER Equal MATERIAL ASSISTANCE RIGHTS law absenc
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优化营商环境背景下我国公平竞争制度建设的基本框架 被引量:4
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作者 王先林 《政法论丛》 CSSCI 北大核心 2024年第3期103-113,共11页
在我国营造市场化、法治化和国际化一流营商环境的过程中,公平竞争是其内在要求和核心内容,这就需要公平竞争制度或者竞争政策予以确认和保障。在我国公平竞争制度建设中,强化竞争政策基础地位是顶层设计,落实公平竞争审查制度是关键环... 在我国营造市场化、法治化和国际化一流营商环境的过程中,公平竞争是其内在要求和核心内容,这就需要公平竞争制度或者竞争政策予以确认和保障。在我国公平竞争制度建设中,强化竞争政策基础地位是顶层设计,落实公平竞争审查制度是关键环节,加强反垄断反不正当竞争是基础保障,引导和激励企业反垄断合规是必要举措。这些方面构成了进一步优化营商环境背景下我国公平竞争制度建设的基本框架。 展开更多
关键词 营商环境 公平竞争制度 竞争法 竞争政策
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我国环境执法模式的反思与革新 被引量:2
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作者 陈海嵩 《暨南学报(哲学社会科学版)》 CSSCI 北大核心 2024年第4期40-54,共15页
在新时代中国环境法治的议题中,环境治理体系的核心环节——环境行政执法是实现生态文明和高质量发展的重要手段。传统“强制型”“威权型”的环境执法模式,已经显露出无法适应新时代生态文明建设需求的局限性。基于习近平生态文明思想... 在新时代中国环境法治的议题中,环境治理体系的核心环节——环境行政执法是实现生态文明和高质量发展的重要手段。传统“强制型”“威权型”的环境执法模式,已经显露出无法适应新时代生态文明建设需求的局限性。基于习近平生态文明思想的系统整体要求,本文主张建立整体化执法理念,推动环境执法从“强制型”向“共治型”的演变,通过对传统环境行政执法的“纠偏”,以便更好地适应包容性强、多元共治、刚柔并济、平等协商、协同互动治理目标的综合实现。为达成这一目标,本文基于系统整体观提出环境治理体系制度层面的深度优化策略,其中包括各类沟通性、非高权性环境行政行为的扩展应用,以及环境执法资源配置的精细化调整。这些措施旨在构建更加灵活和协同的环境治理机制,以适应现代社会多元利益关系的复杂性。 展开更多
关键词 现代环境治理体系 环境执法 系统整体观 制度转型
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我国法治体系建设中的立法质量评估与分析——基于2020年28省份法学专家的调研数据 被引量:1
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作者 张龑 江烁 《北京行政学院学报》 CSSCI 北大核心 2024年第1期29-39,共11页
从中国特色社会主义法律体系建设进入法治体系建设的新时代,立法质量成为法治建设的重要内容。从法理角度观察,我国立法质量建设不是从无到有的建设,而是提升法律规范性品质的建设,为此要构建一套符合我国法治建设实际的立法质量评估体... 从中国特色社会主义法律体系建设进入法治体系建设的新时代,立法质量成为法治建设的重要内容。从法理角度观察,我国立法质量建设不是从无到有的建设,而是提升法律规范性品质的建设,为此要构建一套符合我国法治建设实际的立法质量评估体系。基于详实的问卷调查数据,本评估体系将立法质量判断标准建立在指标得分及指标之间内在逻辑的双重基础之上,改变了以往仅凭指标简单加权平均来评估立法成效的方式,实现了立法整体发展水平和立法中各项要素发展情况的刻度化测评,从而有助于把握立法规律和现状,准确评估当前立法水平,以提升立法的规范性品质。 展开更多
关键词 法律体系 法治体系 法律规范性品质 立法质量评估
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刑事案例指导制度统一法律适用的机制完善 被引量:2
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作者 李翔 《东方法学》 CSSCI 北大核心 2024年第1期179-188,共10页
案例指导制度的功能定位在于统一法律适用。法教义学的理论供给缺位、司法解释的抽象性、新兴的疑难案件和传统的边缘案件都可能给法律的统一适用造成阻碍,而案例指导制度对这些阻碍因素均有化解作用。指导性案例的生命力在于其所建议... 案例指导制度的功能定位在于统一法律适用。法教义学的理论供给缺位、司法解释的抽象性、新兴的疑难案件和传统的边缘案件都可能给法律的统一适用造成阻碍,而案例指导制度对这些阻碍因素均有化解作用。指导性案例的生命力在于其所建议的处理方案的优越性,不应赋予其强制效力。为实现该制度的应然的功能定位,指导性案例必须具备翔实的说理。此外,还应当以“统一法律适用”为准绳,优化当前指导性案例的选编制度以及相关的配套机制。 展开更多
关键词 案例指导制度 法律适用 强制适用 选编制度 疑难案件 法教义学
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APPLICATION OF DIRECT BTT GUIDANCE LAW BASED ON NONLINEAR INVERSE SYSTEM THEORY TO INTEGRATED FIRE/FLIGHT SYSTEMS(IFFS)
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作者 Ma Xiaojun Zhang Minglian Wen Chuanyuan(Faculty 305, Beijing University Of Aeronautics and Astronautics,Beijing, China, 100083) 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 1996年第4期305-311,共7页
To counter BTT guidance mode, new relative motion equations of the targetaircraft and the attack aircraft are proposed. The inverse system theory of the nonlinearcontrol is used, and the direct BTT-180 guidance comman... To counter BTT guidance mode, new relative motion equations of the targetaircraft and the attack aircraft are proposed. The inverse system theory of the nonlinearcontrol is used, and the direct BTT-180 guidance command is solved, which can operatethe attack aircraft to automatically complete the flight mission of the preceding stage ofthe terminal weapon delivery, and thus the automatic attack is extended from the stage ofthe terminal weapon delivery to the preceding stage of the terminal weapon delivery. 展开更多
关键词 fire control flight control nonlinear systems inverse system direct BTT guidance law automatic control ATTACK
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教育学自主知识体系的本质特征和建构规律 被引量:4
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作者 郝文武 《西北师大学报(社会科学版)》 CSSCI 北大核心 2024年第1期77-85,共9页
教育学自主知识体系是教育主体自主建构的全面深入反映教育本质和规律的知识系统;是在海内外文化、不同学科知识相互影响、交融中形成的知识体系;是合目的与合规律、价值追求与思维逻辑统一的知识体系;是继承与发展、守正与创新结合形... 教育学自主知识体系是教育主体自主建构的全面深入反映教育本质和规律的知识系统;是在海内外文化、不同学科知识相互影响、交融中形成的知识体系;是合目的与合规律、价值追求与思维逻辑统一的知识体系;是继承与发展、守正与创新结合形成的知识体系。这既是教育学自主知识体系的本质,也决定了它形成的规律和原则、方式、途径。 展开更多
关键词 教育学 自主知识体系 本质特征 建构规律
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