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Function S-rough sets and mining-discovery of rough law in systems 被引量:25
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作者 Shi Kaiquan Xia Jiarong 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2006年第4期919-926,共8页
Function S-rough sets (function singular rough sets) is defined on a -function equivalence class [u]. Function S-rough sets is the extension form of S-rough sets. By using the function S-rough sets, this paper gives... Function S-rough sets (function singular rough sets) is defined on a -function equivalence class [u]. Function S-rough sets is the extension form of S-rough sets. By using the function S-rough sets, this paper gives rough law generation model of a-function equivalence class, discussion on law mining and law discovery in systems, and application of law mining and law discovery in communication system. Function S-rough sets is a new theory and method in law mining research. 展开更多
关键词 function S-rough sets structure of function S-rough sets relationship theorem rough law mining-discovery applications.
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Interaction of elementary waves of scalar conservation laws with discontinuous flux function 被引量:3
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作者 王国栋 盛万成 《Journal of Shanghai University(English Edition)》 CAS 2006年第5期381-387,共7页
In this paper, the Riemann solutions for scalar conservation laws with discontinuous flux function were constructed. The interactions of elementary waves of the conservation laws were concerned, and the numerical simu... In this paper, the Riemann solutions for scalar conservation laws with discontinuous flux function were constructed. The interactions of elementary waves of the conservation laws were concerned, and the numerical simulations were given. 展开更多
关键词 discontinuous flux function scalar conservation laws linear discontinuity shock wave rarefaction wave.
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Size-dependent vibration and buckling of porous functionally graded microplates based on modified couple stress theory in thermal environments by considering a dual power-law distribution of scale effects 被引量:1
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作者 Feixiang TANG Shaonan SHI +2 位作者 Siyu HE Fang DONG Sheng LIU 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第12期2075-2092,共18页
In this study,the thermodynamic behaviors of the intrinsic frequency and buckling temperature of rectangular plates of functionally graded materials(FGMs)are explored based on the modified couple stress theory(MCST)an... In this study,the thermodynamic behaviors of the intrinsic frequency and buckling temperature of rectangular plates of functionally graded materials(FGMs)are explored based on the modified couple stress theory(MCST)and the novel dual powerlaw scale distribution theory.The effects of linear,homogeneous,and non-homogeneous temperature fields on the frequency and buckling temperature of FGM microplates are evaluated in detail.The results show that the porosity greatly affects the mechanical properties of FGM plates,reducing their frequency and flexural temperature compared with non-porous plates.Different temperature profiles alter plate frequencies and buckling temperatures.The presence and pattern of scale effect parameters are also shown to be crucial for the mechanical response of FGM plates.The present research aims to provide precise guidelines for the micro-electro-mechanical system(MEMS)fabrication by elucidating the complex interplay between thermal,material,and structural factors that affect the performance of FGM plates in advanced applications. 展开更多
关键词 thermal vibration dual power law functionally graded material(FGM) pore distribution scale effect scale distribution thermal buckling
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Function S-rough Sets and Their Law Characteristic 被引量:1
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作者 李东亚 史开泉 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2007年第2期225-231,共7页
Function S-rough sets(Function Singular rough sets) are defined by R-function equivalence class which has dynamic characteristic, and a function is s law, function S-rough sets have law characteristic. Function S-roug... Function S-rough sets(Function Singular rough sets) are defined by R-function equivalence class which has dynamic characteristic, and a function is s law, function S-rough sets have law characteristic. Function S-rough sets has these forms: function one direction S-rough sets, function two direction S-rough sets and dual of function one direction S-rough sets. This paper presents the law characteristic of function one direction S-rough sets and puts forward the theorems of law-chain-attribute and law-belt. Function S-rough sets is s new research direction of the rough sets theory. 展开更多
关键词 function one direction S-rough sets law the theorem of law-chain-attribute the theorem of law-belt
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Function P-sets and Mining-discovery Theorems of Unknown Information Law
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作者 赵文菊 李东亚 《Chinese Quarterly Journal of Mathematics》 CSCD 2011年第4期488-493,共6页
Function P-sets are a set pair which are composed of function internal packetsets S F and function outer packet sets S F or (S F , S F ) are function P-sets. Function P-sets have dynamic characteristics and law charac... Function P-sets are a set pair which are composed of function internal packetsets S F and function outer packet sets S F or (S F , S F ) are function P-sets. Function P-sets have dynamic characteristics and law characteristics. Based on function P-sets, P-information law discovery theorems which has attribute supplementing-deleting are given. Mining-discovery and mining-discovery theorems of unknown information law are proposed. Function P-sets are a new theory and new method to research dynamic information laws for information systems. 展开更多
关键词 function P-sets dynamic characteristics law characteristics law sptitsynthesis law discovery
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Function S-rough sets and two law forecast
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作者 Fu Haiyan Shi Kaiquan 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2009年第2期332-338,共7页
Function S-rough sets has the properties of dynamics, heredity, and memory. Function S-rough sets is penetrated and crossed with the issue of economic law forecast, then a new forecast model based on function S-rough ... Function S-rough sets has the properties of dynamics, heredity, and memory. Function S-rough sets is penetrated and crossed with the issue of economic law forecast, then a new forecast model based on function S-rough sets namely the two law forecast model is proposed, which includes upper law forecast model and lower law forecast model; and its' implement algorithm is given. Finally, the validity of the model is demonstrated by the forecast for region economic development of Hainan Province. 展开更多
关键词 function S-rough sets two law forecast dynamic economic system
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Experimental researches for scaling laws of low-order structure function in boundary layer
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作者 张珂 李万平 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2010年第6期806-811,共6页
Scaling laws are addressed by analysing moments of velocity increments which obtained by Particle-image Velocimetry(PIV)system in the boundary layer of a flat plate.In the paper,we measure the moments of increments of... Scaling laws are addressed by analysing moments of velocity increments which obtained by Particle-image Velocimetry(PIV)system in the boundary layer of a flat plate.In the paper,we measure the moments of increments of upstream velocity(u'),longitudinal velocity(v')and ponderance of vorticity(dv'/dx)at Reθ=2167 in different wall distance and verify the anomaly of the scaling exponents of high-order structure functions with the increasing order of the moments,discuss the scaling of non-integer moments of order between+2 and-1.The difference of scaling exponents of low-order structure functions between the experimental data and Kolmogorov's,SL's(She & Leveque)prediction increases as the moment order decreases toward-1,which shows that the anomaly is manifested in low-oeder moments as well.However,for same order structure functions,the scaling exponents of v' and dv'/dx are not changeable in different wall distance. 展开更多
关键词 scaling law low-order structure function turbulent boundary layer scaling exponent
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The Effectiveness of the Squared Error and Higgins-Tsokos Loss Functions on the Bayesian Reliability Analysis of Software Failure Times under the Power Law Process
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作者 Freeh N. Alenezi Christ P. Tsokos 《Engineering(科研)》 2019年第5期272-299,共28页
Reliability analysis is the key to evaluate software’s quality. Since the early 1970s, the Power Law Process, among others, has been used to assess the rate of change of software reliability as time-varying function ... Reliability analysis is the key to evaluate software’s quality. Since the early 1970s, the Power Law Process, among others, has been used to assess the rate of change of software reliability as time-varying function by using its intensity function. The Bayesian analysis applicability to the Power Law Process is justified using real software failure times. The choice of a loss function is an important entity of the Bayesian settings. The analytical estimate of likelihood-based Bayesian reliability estimates of the Power Law Process under the squared error and Higgins-Tsokos loss functions were obtained for different prior knowledge of its key parameter. As a result of a simulation analysis and using real data, the Bayesian reliability estimate under the Higgins-Tsokos loss function not only is robust as the Bayesian reliability estimate under the squared error loss function but also performed better, where both are superior to the maximum likelihood reliability estimate. A sensitivity analysis resulted in the Bayesian estimate of the reliability function being sensitive to the prior, whether parametric or non-parametric, and to the loss function. An interactive user interface application was additionally developed using Wolfram language to compute and visualize the Bayesian and maximum likelihood estimates of the intensity and reliability functions of the Power Law Process for a given data. 展开更多
关键词 Power law Process BAYESIAN Reliability Intensity function KERNEL Density Loss function Robustness
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Local Rate of Convergence in the Functional Limit Theorem for Increments of a Fractional Brownian Motion 被引量:1
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作者 LIU Yonghong DING Ding ZHOU Xia 《数学进展》 北大核心 2025年第1期197-211,共15页
In this paper,we present local functional law of the iterated logarithm for Cs?rg?-Révész type increments of fractional Brownian motion.The results obtained extend works of Gantert[Ann.Probab.,1993,21(2):104... In this paper,we present local functional law of the iterated logarithm for Cs?rg?-Révész type increments of fractional Brownian motion.The results obtained extend works of Gantert[Ann.Probab.,1993,21(2):1045-1049]and Monrad and Rootzén[Probab.Theory Related Fields,1995,101(2):173-192]. 展开更多
关键词 fractional Brownian motion INCREMENT local functional law of the iterated logarithm large deviation small deviation
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A LAW OF THE ITERATED LOGARITHM FOR NEAREST NEIGHBOR ESTIMATION OF MULTIVARIATE DENSITY FUNCTION
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作者 洪圣岩 陈规景 +1 位作者 孔繁超 高集体 《Acta Mathematica Scientia》 SCIE CSCD 1992年第4期472-478,共7页
Let X be a d-dimensional random vector with unknown density function f(z) = f (z1, ..., z(d)), and let f(n) be teh nearest neighbor estimator of f proposed by Loftsgaarden and Quesenberry (1965). In this paper, we est... Let X be a d-dimensional random vector with unknown density function f(z) = f (z1, ..., z(d)), and let f(n) be teh nearest neighbor estimator of f proposed by Loftsgaarden and Quesenberry (1965). In this paper, we established the law of the iterated logarithm of f(n) for general case of d greater-than-or-equal-to 1, which gives the exact pointwise strong convergence rate of f(n). 展开更多
关键词 A law OF THE ITERATED LOGARITHM FOR NEAREST NEIGHBOR ESTIMATION OF MULTIVARIATE DENSITY function exp
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Valence electron matching law for MXene-based single-atom catalysts
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作者 Pei Song Yuhang Zhou +9 位作者 Zishan Luo Hang Zhang Xi Sun Sen Lu Zepeng Jia Hong Cui Weizhi Tian Rong Feng Lingxia Jin Hongkuan Yuan 《Journal of Energy Chemistry》 2025年第2期641-650,I0013,共11页
Single-atom catalysts(SACs)have attracted considerable interest in the fields of energy and environmental science due to their adjustable catalytic activity.In this study,we investigated the matching of valence electr... Single-atom catalysts(SACs)have attracted considerable interest in the fields of energy and environmental science due to their adjustable catalytic activity.In this study,we investigated the matching of valence electron numbers between single atoms and adsorbed intermediates(O,N,C,and H)in MXene-anchored SACs(M-Ti_(2)C/M-Ti_(2)CO_(2)).The density functional theory results demonstrated that the sum of the valence electron number(VM)of the interface-doped metal and the valence electron number(VA)of the adsorbed intermediates in M-Ti_(2)C followed the 10-valence electron matching law.Furthermore,based on the 10-valence electron matching law,we deduced that the sum of the valence electron number(k)and VMfor the molecular adsorption intermediate interactions in M-Ti_(2)CO_(2)adhered to the 11-valence electron matching law.Electrostatic repulsion between the interface electrons in M-Ti_(2)CO_(2)and H_(2)O weakened the adsorption of intermediates,Furthermore,we applied the 11-valence electron matching law to guide the design of catalysts for nitrogen reduction reaction,specifically for N_(2)→NNH conversion,in the MTi_(2)CO_(2)structure.The sure independence screening and sparsifying operator algorithm was used to fit a simple three-dimensional descriptor of the adsorbate(R_(2)up to 0.970)for catalyst design.Our study introduced a valence electron matching principle between doped metals(single atoms)and adsorbed intermediates(atomic and molecular)for MXene-based catalysts,providing new insights into the design of high-performance SACs. 展开更多
关键词 Density functional theory Nitrogen reduction reaction Sure independence screening and sparsifying operator Valence electron matching law
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新形势下民营经济发展的经济法促进:误区澄清与进路展开
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作者 王怀勇 董磊 《重庆大学学报(社会科学版)》 北大核心 2026年第1期197-210,共14页
随着《民营经济促进法》的出台,民营经济发展法治促进的形势发生了较大变化。《民营经济促进法》成为民营经济领域基本法,民营经济法律规范群的格局得以重塑;法治进路由立法促进向执法促进、司法促进拓展,理论焦点由立法论向解释论转型... 随着《民营经济促进法》的出台,民营经济发展法治促进的形势发生了较大变化。《民营经济促进法》成为民营经济领域基本法,民营经济法律规范群的格局得以重塑;法治进路由立法促进向执法促进、司法促进拓展,理论焦点由立法论向解释论转型,民营经济法治工作的重心得以调整;经济法角色由“重要参与者”向“核心推动者”过渡,民营经济愈发有赖于经济法促进。在此新形势下,阐明促进民营经济发展的经济法进路正当其时。然而,学界对经济法促进的理解还存在误区和模糊地带。主要涉及三个层面:一是规范层面,将新形势下民营经济发展的经济法促进简化为《民营经济促进法》的实施;二是功能层面,否认或者放弃《民营经济促进法》的“扶弱”功能;三是制度层面,淡化《民营经济促进法》解决民营经济特殊问题而非共性问题的制度倾向。实际上,新形势下经济法促进围绕《民营经济促进法》的实施而展开,不限于《民营经济促进法》的实施,若将经济法促进简化为《民营经济促进法》的实施,便陷入了“以偏概全”的认知误区,有“将复杂问题简单化”之嫌;“纠偏”与“扶弱”均是《民营经济促进法》的核心功能,不可偏废,若否定或者放弃“扶弱”功能,便人为“阉割”了《民营经济促进法》的促进功能,有“被功能定位绑住了手脚”之虞;《民营经济促进法》具有鲜明的解决特殊问题的倾向,这与其作为领域基本法的定位并不冲突,若淡化其解决特殊问题的制度倾向,便违背了以问题导向式立法为基础的领域法学的特殊旨趣,有“自我否定存在价值”之忧。为此,今后应当以持续推进《民营经济促进法》的实施及其配套法规的出台为中心,坚持“以促进型经济法为主、以限禁型经济法为辅”的规范布局,沿着“纠偏”与“扶弱”并进的功能进路,聚焦完善民营经济针对性促进制度的制度安排,构建从规范到功能再到制度的多维度经济法进路,加强新形势下民营经济发展的经济法促进,进而助推民营经济实现高质量发展。 展开更多
关键词 民营经济 《民营经济促进法》 经济法 功能定位 制度倾向
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作为立法表达方式的“姿态”:概念、类型与评价
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作者 朱志昊 《法治社会》 2026年第2期117-130,共14页
我国立法实践中存在以宣示表达、价值倡导或鼓励促进为目标的立法,其缺乏具体操作机制而呈现姿态化特征。立法的姿态是立法者意志的特殊表达方式,在我国实践中包括宣示型、回应—展示型与开放型三种类型。立法姿态并不必然代表立法质量... 我国立法实践中存在以宣示表达、价值倡导或鼓励促进为目标的立法,其缺乏具体操作机制而呈现姿态化特征。立法的姿态是立法者意志的特殊表达方式,在我国实践中包括宣示型、回应—展示型与开放型三种类型。立法姿态并不必然代表立法质量欠佳,其合理性应结合具体立法领域与社会语境进行判断。宣示型姿态有助于政治认同构建,开放型姿态承担了弹性治理和意见整合的功能,回应—展示型姿态则应注意立法的问题导向和实际效果。在共性方面,立法姿态的合理性取决于是否建立在有效的立法互动基础之上,即立法过程能否实现多元参与和互动。立法应当平衡法律的表达性与实效性,在法治轨道上推进科学立法与民主立法。 展开更多
关键词 姿态 法律的表达功能 促进型立法 新兴领域立法 象征互动理论
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Design and Application of Discrete Sliding Mode Control with RBF Network-based Switching Law 被引量:6
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作者 牛建军 付永领 祁晓野 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2009年第3期279-284,共6页
This article proposes a novel approach combining exponential-reaching-law-based equivalent control law with radial basis function (RBF) network-based switching law to strengthen the sliding mode control (SMC) tracking... This article proposes a novel approach combining exponential-reaching-law-based equivalent control law with radial basis function (RBF) network-based switching law to strengthen the sliding mode control (SMC) tracking capacity for systems with uncertainties and disturbances. First, SMC discrete equivalent control law is designed on the basis of the nominal model of the system and the adaptive exponential reaching law, and subsequently, stability of the algorithm is analyzed. Second, RBF network is used to f... 展开更多
关键词 sliding mode control switching law design radial basis function networks flight simulators extra-low speed servo
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基于Lyapunov稳定框架的轮式移动机器人轨迹跟踪
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作者 崔光海 杨光永 +2 位作者 陈胜锦 张文博 徐天奇 《组合机床与自动化加工技术》 北大核心 2026年第3期145-150,共6页
为提高轮式移动机器人(WMR)轨迹跟踪控制精度,基于运动学模型研究了轮式移动机器人的轨迹跟踪控制问题。首先,在轮式移动机器人质心和几何中心重合的情况下,设计了基于运动学的控制器,在此基础上,为消除周期性误差带来的影响,引入正切... 为提高轮式移动机器人(WMR)轨迹跟踪控制精度,基于运动学模型研究了轮式移动机器人的轨迹跟踪控制问题。首先,在轮式移动机器人质心和几何中心重合的情况下,设计了基于运动学的控制器,在此基础上,为消除周期性误差带来的影响,引入正切函数项,提出了一种新的Lyapunov函数,并利用该函数设计了一种周期控制律;其次,对于轮式移动机器人质心和几何中心之间距离不为零且未知的情况,加入自适应算法来补偿未知参数引起的系统误差,并利用Lyapunov函数构造一个全局跟踪控制律;最后,利用MATLAB/Simulink仿真平台对设计的控制器进行仿真实验,结果表明所提控制器的有效性。 展开更多
关键词 轮式移动机器人 轨迹跟踪 LYAPUNOV函数 自适应律 周期性
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数字技术驱动下版权刑事保护的范式转型
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作者 陈超 《法学论坛》 北大核心 2026年第1期45-57,共13页
在数字化和网络化推动下,通过数字化创作、数字媒体获取信息、传播分享内容已经成为日常生活工作中不可或缺的部分。然而技术发展带来生活便利的同时也引发了数字时代版权治理的诸多问题,尤其是在积极主义刑法治理立场下,版权刑事治理... 在数字化和网络化推动下,通过数字化创作、数字媒体获取信息、传播分享内容已经成为日常生活工作中不可或缺的部分。然而技术发展带来生活便利的同时也引发了数字时代版权治理的诸多问题,尤其是在积极主义刑法治理立场下,版权刑事治理不断扩张不仅冲击着传统刑法理论基础,更侵蚀着著作权利益平衡的基本格局。基于对知识产权法哲学以及相应的刑法解释立场的考察,数字时代版权刑事保护范式亟待转型,应遵循审慎功能主义治理机制,在规范适用时恪守限缩解释的立场,在法律运行机制上通过消极司法平衡积极立法,在法律适用上以主观解释限制客观解释,在犯罪判定思维上以实质出罪中和形式入罪。同时,明确审慎功能主义下限缩立场的前提、实质和定位,对具体犯罪构成要件解释作出适当限制,从而在著作权犯罪社会治理中适度限制刑法的介入,以充分提高数字时代作品利用的积极性。 展开更多
关键词 数字技术 版权治理 审慎功能主义 消极刑法观 先民后刑
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分段复合幂次趋近律的滑模控制
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作者 刘旭 智亚丽 +2 位作者 张燕 孙先涛 陈文杰 《控制理论与应用》 北大核心 2026年第3期671-676,共6页
针对传统幂次趋近律作用下的滑模控制中存在的收敛速度缓慢和抖振现象,本文在自适应趋近律和幂次趋近律的基础上,选择分段函数的形式,提出一种分段复合幂次趋近律.通过引入随系统状态变化的平滑函数以及对传统幂次趋近律的改进,保证系... 针对传统幂次趋近律作用下的滑模控制中存在的收敛速度缓慢和抖振现象,本文在自适应趋近律和幂次趋近律的基础上,选择分段函数的形式,提出一种分段复合幂次趋近律.通过引入随系统状态变化的平滑函数以及对传统幂次趋近律的改进,保证系统在各个阶段都具有较快的趋近速率;同时,本文证明所提出的分段复合幂次趋近律能够快速收敛且到达滑模面时无抖振现象,并在系统存在外界干扰时能够收敛于稳态误差界;最后,通过对比仿真证明所提趋近律的有效性和优越性. 展开更多
关键词 滑模控制 平滑函数 分段复合幂次趋近律 稳态误差界
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