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Differential characteristic set algorithm for the complete symmetry classification of partial differential equations
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作者 特木尔朝鲁 白玉山 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2009年第5期595-606,共12页
In this paper, we present a differential polynomial characteristic set algorithm for the complete symmetry classification of partial differential equations (PDEs) with some parameters. It can make the solution to th... In this paper, we present a differential polynomial characteristic set algorithm for the complete symmetry classification of partial differential equations (PDEs) with some parameters. It can make the solution to the complete symmetry classification problem for PDEs become direct and systematic. As an illustrative example, the complete potential symmetry classifications of nonlinear and linear wave equations with an arbitrary function parameter are presented. This is a new application of the differential form characteristic set algorithm, i.e., Wu's method, in differential equations. 展开更多
关键词 partial differential equations SYMMETRY CLASSIFICATION differential characteristic set
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<i>N</i>-Order Fixed Point Theory for N-Order Generalized Meir-Keeler Type Contraction in Partially Ordered Metric Spaces
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作者 Shiyun Wang Jingwen Zhang 《Journal of Applied Mathematics and Physics》 2019年第5期1174-1184,共11页
This paper concerns N-order fixed point theory in partially ordered metric spaces. For the sake of simplicity, we start our investigations with the tripled case. We define tripled generalized Meir-Keeler type contract... This paper concerns N-order fixed point theory in partially ordered metric spaces. For the sake of simplicity, we start our investigations with the tripled case. We define tripled generalized Meir-Keeler type contraction which extends the definition of [Bessem Samet, Coupled fixed point theorems for a generalized Meir-Keeler contraction in partially ordered metric spaces, Nonlinear Anal. 72 (2010), 4508-4517]. We then discuss the existence and uniqueness of tripled fixed point theorems in partially ordered metric spaces. For general cases, we generalized our results to the N-order case. The results will promote the study of N-order fixed point theory. 展开更多
关键词 Tripled Fixed POINT Meir-Keeler TYPE CONTRACTION partially Ordered set N-Order Fixed POINT
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Continuity of Solution Mappings for Parametric Set Optimization Problems under Partial Order Relations
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作者 Yueming Sun 《Advances in Pure Mathematics》 2020年第11期631-644,共14页
This paper mainly investigates the semicontinuity of solution mappings for set optimization problems under a partial order set relation instead of upper and lower set less order relations. To this end, we propose two ... This paper mainly investigates the semicontinuity of solution mappings for set optimization problems under a partial order set relation instead of upper and lower set less order relations. To this end, we propose two types of monotonicity definition for the set-valued mapping introduced by two nonlinear scalarization functions which are presented by these partial order relations. Then, we give some sufficient conditions for the semicontinuity and closedness of solution mappings for parametric set optimization problems. The results presented in this paper are new and extend the main results given by some authors in the literature. 展开更多
关键词 Parametric set Optimization Problem Nonlinear Scalarization Function SEMICONTINUITY partial Order Relation
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Results of Associated Implication Algebra on a Partial Ordered Set
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作者 伊良忠 裴峥 宋文 《Journal of Donghua University(English Edition)》 EI CAS 2007年第2期293-296,共4页
Some sufficient and necessary conditions that implication algebra on a partial ordered set is associated implication algebra are obtained, and the relation between lattice H implication algebra and associated implicat... Some sufficient and necessary conditions that implication algebra on a partial ordered set is associated implication algebra are obtained, and the relation between lattice H implication algebra and associated implication algebra is discussed. Also, the concept of filter is proposed with some basic properties being studied. 展开更多
关键词 partial ordered set implication algebra implication associated attice H implication lgebre FILTER
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Theorems of Helly's Type for Partially-closed Half-spaces
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作者 Liu Jian-Guo Guo Qi 《Communications in Mathematical Research》 CSCD 2018年第2期117-124,共8页
In this article, under quite weaker conditions, theorems of Helly’s type for(not necessarily finite) family of partially closed half-spaces are presented in both analytic and geometric forms. Examples are also provid... In this article, under quite weaker conditions, theorems of Helly’s type for(not necessarily finite) family of partially closed half-spaces are presented in both analytic and geometric forms. Examples are also provided to show that these conditions cannot be omitted in general. 展开更多
关键词 Helly's theorem partially-closed half-space affine function convex set
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一种固定界面的Level Set重新初始化方法 被引量:1
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作者 张莉 吴开腾 宁建国 《兵工学报》 EI CAS CSCD 北大核心 2016年第S2期185-190,共6页
针对Level Set函数重新初始化过程导致的质量不守恒性问题,采用一种固定界面位置的方式,分析了固定界面位置与光滑参数之间的关系,推导了一种光滑参数的选取计算公式。与传统光滑参数的取值相比,本文提出的光滑参数不是固定而是变化的,... 针对Level Set函数重新初始化过程导致的质量不守恒性问题,采用一种固定界面位置的方式,分析了固定界面位置与光滑参数之间的关系,推导了一种光滑参数的选取计算公式。与传统光滑参数的取值相比,本文提出的光滑参数不是固定而是变化的,它依赖于界面附近节点的信息。数值实验结果表明,该方法能够有效地捕捉界面,并能大大提高质量守恒性。 展开更多
关键词 流体力学 偏微分方程 Level set方法 重新初始化 光滑参数
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New partial cooperation model for bilevel programming problems 被引量:4
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作者 Shihui Jia Zhongping Wan +1 位作者 Yuqiang Feng Guangmin Wang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2011年第2期263-266,共4页
Partial cooperation models are studied for many years to solve the bilevel programming problems where the follower’s optimal reaction is not unique. However, in these existed models, the follower’s cooperation level... Partial cooperation models are studied for many years to solve the bilevel programming problems where the follower’s optimal reaction is not unique. However, in these existed models, the follower’s cooperation level does not depend on the leader’s decision. A new model is proposed to solve this deficiency. It is proved the feasibility of the new model when the reaction set of the lower level is lower semicontinuous. And the numerical results show that the new model has optimal solutions when the reaction set of the lower level is discrete, lower semi-continuous and non-lower semi-continuous. 展开更多
关键词 bilevel programming reaction set optimistic model pessimistic model partial cooperation model cooperation level.
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Level Set方法在轮廓界面追踪问题中的应用
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作者 孟凡凡 陆益民 《计算技术与自动化》 2010年第1期80-83,共4页
运用Level Set方法研究图像轮廓追踪问题。首先,运用差分法检测出图像的初始轮廓线,然后采用基于Level Set方法的偏微分方程数值解理论来进行图像轮廓界面的提取。Matlab实验结果表明,该方法可以测出模糊或离散的边界,得到精确的图像轮... 运用Level Set方法研究图像轮廓追踪问题。首先,运用差分法检测出图像的初始轮廓线,然后采用基于Level Set方法的偏微分方程数值解理论来进行图像轮廓界面的提取。Matlab实验结果表明,该方法可以测出模糊或离散的边界,得到精确的图像轮廓界面。 展开更多
关键词 LEVEL set方法 轮廓界面追踪 偏微分方程
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PARTIAL BOCHNER INTEGRABILITY (I)
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作者 陈泽乾 《Acta Mathematica Scientia》 SCIE CSCD 1999年第3期293-299,共7页
This paper is concerned with partial Bochner integrals with emphasis on a geometrical study of partial Bochner integrability. Convex sets involving the range of L-1-bounded functions are constructed. These constructio... This paper is concerned with partial Bochner integrals with emphasis on a geometrical study of partial Bochner integrability. Convex sets involving the range of L-1-bounded functions are constructed. These constructions provide a complete characterization of partial Bochner integrable functions. 展开更多
关键词 Banach space norming set partial Bochner integral
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A SYMBOLIC COMPUTATION METHOD TO DECIDE THE COMPLETENESS OF THE SOLUTIONS TO THE SYSTEM OF LINEAR PARTIAL DIFFERENTIAL EQUATIONS
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作者 张鸿庆 谢福鼎 陆斌 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2002年第10期1134-1139,共6页
A symbolic computation method to decide whether the solutions to the system Of linear partial differential equation is complete via using differential algebra and characteristic set is presented. This is a mechanizati... A symbolic computation method to decide whether the solutions to the system Of linear partial differential equation is complete via using differential algebra and characteristic set is presented. This is a mechanization method, and it can be carried out on the computer in the Maple environment. 展开更多
关键词 differential algebra system of partial differential equation symbolic computation characteristic set
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EKELAND’S VARIATIONAL PRINCIPLE AND CARISTI’S COINCIDENCE THEOREM FOR SET-VALUED MAPPINGS IN PROBABILISTIC METRIC SPACES
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作者 张石生 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1993年第7期607-614,共8页
By using the partial ordering method,a more general type,of Ekeland’s ariational principle and a set-valued Caristi’s coincidence theorem in probabilistic metric spaces are obtained.In addition,a direct simple proof... By using the partial ordering method,a more general type,of Ekeland’s ariational principle and a set-valued Caristi’s coincidence theorem in probabilistic metric spaces are obtained.In addition,a direct simple proof of the equivalence between these two theorems in probabilistic metric spaces is given. 展开更多
关键词 probabilistic metric space Caristi's coincidence theorem Ekeland's variational principle partial ordering set.
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Some Fixed Point Results of Ciric-Type Contraction Mappings on Ordered <i>G</i>-Partial Metric Spaces
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作者 Johnson O. Olaleru Kanayo Stella Eke Hallowed O. Olaoluwa 《Applied Mathematics》 2014年第6期1004-1012,共9页
We introduce the concept of generalized quasi-contraction mappings in G-partial metric spaces and prove some fixed point results in ordered G-partial metric spaces. The results generalize and extend some recent result... We introduce the concept of generalized quasi-contraction mappings in G-partial metric spaces and prove some fixed point results in ordered G-partial metric spaces. The results generalize and extend some recent results in literature. 展开更多
关键词 Fixed Points Generalized Quasi-Contraction Maps Bounded Orbit partially ORDERED set G-partial Metric Spaces
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Partial Groups, Simplicial K(G, 1)’s and Kan Complexes
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作者 Solomon Jekel 《Advances in Pure Mathematics》 2023年第11期725-731,共7页
In our paper Simplicial K(G, 1)’s we constructed a sub-complex of the nerve of a group G determined by a partial group structure, and we proved, under a generalized associativity condition called regularity, that the... In our paper Simplicial K(G, 1)’s we constructed a sub-complex of the nerve of a group G determined by a partial group structure, and we proved, under a generalized associativity condition called regularity, that the sub-complex realizes as a K(G, 1). This type of sub-complex appears naturally in several topological and algebraic contexts. In this note we prove that regularity of a partial group implies that the Kan extension condition is satisfied on its nerve in dimensions greater than one, and in dimension one a weaker version of the extension condition holds. 展开更多
关键词 partial Group Simplicial set NERVE Kan Extension
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单边区间集模糊半概念的知识表示及提取方法
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作者 毛华 胥德华 +3 位作者 刘川 郑博雅 王刚 张植明 《智能系统学报》 CSCD 北大核心 2024年第4期1016-1026,共11页
为了使“区间”形式加以表述的不确定信息的提取具有侧重性,需提取出对象(属性)集对应的属性(对象)区间集。本文在模糊形式背景中,通过引入2个阈值,将单边区间集与经典半概念结合,提取出属性(对象)集对应的对象(属性)区间集,从而提出区... 为了使“区间”形式加以表述的不确定信息的提取具有侧重性,需提取出对象(属性)集对应的属性(对象)区间集。本文在模糊形式背景中,通过引入2个阈值,将单边区间集与经典半概念结合,提取出属性(对象)集对应的对象(属性)区间集,从而提出区间集外延–集合内涵(集合外延–区间集内涵)(interval set extent-set intent(set extent-interval set intent),ISE-SI(SE-ISI))型单边区间集模糊半概念。全体ISE-SI(SE-ISI)型单边区间集模糊半概念构成格,并给出基于格搜寻全体ISE-SI(SE-ISI)型单边区间集模糊半概念的算法。通过与已有成果对比,显示出这2种知识表示形式的多方优势。本文所得结果在知识表示及提取方法上具有适用范围广、实际应用强等优点。 展开更多
关键词 模糊形式背景 半概念 区间集 区间集概念 单边区间集概念 模糊概念 单边区间集模糊半概念 知识表示和提取
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From Optimal Stopping Problems over Tree Sets to Optimal Stopping Problems over Partially Ordered Sets 被引量:1
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作者 易东云 《Journal of Mathematical Research and Exposition》 CSCD 1998年第1期30-32,共3页
In this paper, we discuss relations between optimal stopping problems over tree sets and partially ordered sets, prove that there is a 1-1 correspondence between them and so every optimal strategy can be obtained in t... In this paper, we discuss relations between optimal stopping problems over tree sets and partially ordered sets, prove that there is a 1-1 correspondence between them and so every optimal strategy can be obtained in the set of optimal control variables. 展开更多
关键词 partially ordered set optimal stopping optimal strategy.
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偏序集上非自映射的最佳逼近点定理
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作者 陈丽君 《长春师范大学学报》 2024年第6期1-4,共4页
给出广义收缩非自映射的概念,证明了该非自映射在偏序集上的最佳逼近点定理,并举例支持本文的研究结果.所得结果推广了相关文献的结论,尤其无偏序关系的距离空间中非自映射的最佳逼近点定理是本文结论的一个特殊情况.
关键词 最佳逼近点 广义压缩 收敛性 偏序集
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基于组合赋权-偏序集的应急供应链可靠性评价
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作者 王丹 高雯雯 《中国安全科学学报》 CAS CSCD 北大核心 2024年第5期231-237,共7页
为协调好应急供应链中物资的分配与使用,基于文献分析等方法提炼应急供应链可靠性评价指标,建立由组织保障可靠性、系统制度可靠性以及运作流程可靠性3个一级指标及其对应的17个二级指标组成的应急供应链可靠性评价指标体系;利用层次分... 为协调好应急供应链中物资的分配与使用,基于文献分析等方法提炼应急供应链可靠性评价指标,建立由组织保障可靠性、系统制度可靠性以及运作流程可靠性3个一级指标及其对应的17个二级指标组成的应急供应链可靠性评价指标体系;利用层次分析法(AHP)、熵权法(EWM)和三角模糊数计算指标权重,将蕴含权重信息的偏序关系引入评价研究中,构建组合赋权-偏序集模型评价应急供应链的可靠性,并应用该模型评价分析C市5个县级城市的应急供应链可靠性水平。结果表明:5个县级城市的应急供应链可靠性程度可分为4类,其中,地区03的可靠性水平高,地区04、02的可靠性水平较高,地区05的可靠性水平中等,而地区01的可靠性水平低;通过对比分析,获取各地区的优势环节和薄弱环节以及需改进的地方。该评价模型可有效评估应急供应链可靠性水平。 展开更多
关键词 组合赋权 偏序集 应急供应链 可靠性评价 层次分析法(AHP) 熵权法(EWM)
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Existence and Uniqueness of Fixed Point in Partially Ordered Sets and Applications to Ordinary Differential Equations 被引量:15
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作者 Juan J.NIETO RosanaRODRGUEZ-LPEZ 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2007年第12期2205-2212,共8页
We prove some fixed point theorems in partially ordered sets, providing an extension of the Banach contractive mapping theorem. Having studied previously the nondecreasing case, we consider in this paper nonincreasing... We prove some fixed point theorems in partially ordered sets, providing an extension of the Banach contractive mapping theorem. Having studied previously the nondecreasing case, we consider in this paper nonincreasing mappings as well as non monotone mappings. We also present some applications to first-order ordinary differential equations with periodic boundary conditions, proving the existence of a unique solution admitting the existence of a lower solution. 展开更多
关键词 fixed point partially ordered set first-order differential equation lower and upper solutions
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Quasi-shadowing Property on Random Partially Hyperbolic Sets 被引量:2
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作者 Lin WANG Xin Sheng WANG Yu Jun ZHU 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2018年第9期1429-1444,共16页
Abstract In this paper we investigate the quasi-shadowing property for C1 random dynamical sys-terns on their random partially hyperbolic sets. It is shown that for any pseudo orbit {xk}+∞ -∞ on a random partially ... Abstract In this paper we investigate the quasi-shadowing property for C1 random dynamical sys-terns on their random partially hyperbolic sets. It is shown that for any pseudo orbit {xk}+∞ -∞ on a random partially hyperbolic set there exists a "center" pseudo orbit {Yk}+∞ -∞ shadowing it in the sense that yk+l is obtained from the image of yk by a motion along the center direction. Moreover, when the random partially hyperbolic set has a local product structure, the above "center" pseudo orbit{yk}+∞ -∞ can be chosen such that yk+1 and the image of yk lie in their common center leaf. 展开更多
关键词 Quasi-shadowing property random partially hyperbolic set local product structure
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基于局部攻击图的最小关键漏洞集分析方法
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作者 沈霄梦 徐丙凤 何高峰 《计算机工程与设计》 北大核心 2024年第6期1607-1614,共8页
为缓解攻击图应用在工业互联网安全防护中的状态空间爆炸问题,提出一种基于局部攻击图的最小关键漏洞集分析方法。提出一种以重要资产节点为目标的局部攻击图生成算法,通过裁剪不可达目标节点的攻击路径缓解状态空间爆炸问题;基于局部... 为缓解攻击图应用在工业互联网安全防护中的状态空间爆炸问题,提出一种基于局部攻击图的最小关键漏洞集分析方法。提出一种以重要资产节点为目标的局部攻击图生成算法,通过裁剪不可达目标节点的攻击路径缓解状态空间爆炸问题;基于局部攻击图生成过程中得到的攻击路径漏洞集直接进行最小关键漏洞集分析,节省传统分析方法在搜索关键漏洞过程中对攻击图进行二次遍历的时空开销。在此基础上,通过工业网络实例进行分析并开展相关工作比较,实验结果表明,所提方法合理可行,可高效分析网络系统中的最小关键漏洞集。 展开更多
关键词 工业互联网 攻击图 关键漏洞集 状态空间爆炸 网络安全 局部攻击图生成 安全防御
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