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Fixed Point of a Countable Family of Uniformly Totally Quasi- <i>&Oslash</i>-Asymptotically Nonexpansive Multi-Valued Mappings in Reflexive Banach Spaces with Applications 被引量:1
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作者 Yi Li 《Applied Mathematics》 2013年第9期6-12,共7页
The purpose of this article is to discuss a modified Halpern-type iteration algorithm for a countable family of uniformly totally quasi- ? -asymptotically nonexpansive multi-valued mappings and establish some strong c... The purpose of this article is to discuss a modified Halpern-type iteration algorithm for a countable family of uniformly totally quasi- ? -asymptotically nonexpansive multi-valued mappings and establish some strong convergence theorems under certain conditions. We utilize the theorems to study a modified Halpern-type iterative algorithm for a system of equilibrium problems. The results improve and extend the corresponding results of Chang et al. (Applied Mathematics and Computation, 218, 6489-6497). 展开更多
关键词 MULTI-VALUED Mapping Totally Quasi- Ø -Asymptotically NONEXPANSIVE countable FAMILY of UNIFORMLY Totally Quasi- Ø -Asymptotically NONEXPANSIVE MULTI-VALUED Mappings Firmly Convergence
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Reflected BSDEs Driven by L&eacute;vy Processes and Countable Brownian Motions
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作者 Jean-Marc Owo 《Applied Mathematics》 2015年第14期2240-2247,共8页
A new class of reflected backward stochastic differential equations (RBSDEs) driven by Teugels martingales associated with Lévy process and Countable Brownian Motions are investigated. Via approximation, the exis... A new class of reflected backward stochastic differential equations (RBSDEs) driven by Teugels martingales associated with Lévy process and Countable Brownian Motions are investigated. Via approximation, the existence and uniqueness of solution to this kind of RBSDEs are obtained. 展开更多
关键词 Backward DOUBLY Stochastic Differential Equations Lévy PROCESSES Teugels MARTINGALES countable BROWNIAN Motions
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Poincaré Inequalities on a Countable Set E and Ω={x:0≤x_i≤a, i=1,2,…,n}
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作者 陈文英 《Journal of Southwest Jiaotong University(English Edition)》 2005年第1期92-94,共3页
In the study of Poincaré inequalities, most of the traditional methods were based on the bounded domain in n dimensional Euclidean space Rn, while the method in this paper is based on a countable set E and accord... In the study of Poincaré inequalities, most of the traditional methods were based on the bounded domain in n dimensional Euclidean space Rn, while the method in this paper is based on a countable set E and accordingly the accurate expressions of Poincaré inequalities JB(=(f-μ(f))nJB)=_B≤cD(f, f) is presented to expand the research and application scope. As to inequalities for Ω={DK(x:0DK)≤x_i≤a, i=1,2,…,n}, the existing studies was usually made for n=2, but such an inequality was not the best. Therefore, the different values of n is discussed in this paper, and accordingly the accurate expressions of Poincaré inequalities is presented. 展开更多
关键词 countable set Poincaré inequalities Weight function
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On Inverse Limits of Normal δθ-refinable Spaces
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作者 CAO Jin-wen (College of Information Management, Chengdu University of Technol ogy, Chengdu 610059, China) 《Chinese Quarterly Journal of Mathematics》 CSCD 2003年第3期286-290,共5页
This paper proves the following results: Le t X= lim ←{X σ,π σ ρ,Λ},|Λ|=λ, and every p rojection π σ: X→X σ be an open and onto mapping. (A) If X is λ-paracompact and every X σ is normal and δθ-ref... This paper proves the following results: Le t X= lim ←{X σ,π σ ρ,Λ},|Λ|=λ, and every p rojection π σ: X→X σ be an open and onto mapping. (A) If X is λ-paracompact and every X σ is normal and δθ-refinable, then X is normal and δθ-refinable; (B) If X is hereditarily λ-pa racompact and every X σ is hereditarily normal and hereditarily δθ- refinable, then X is hereditarily normal and hereditarily δθ-refiable . 展开更多
关键词 inverse limit Λ-PARACOMPACT normal and δθ -refinable hereditarily normal hereditarily δθ-refinable.
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On Spaces with a Locally Countable sn-network
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作者 KANG Bi-fang YAN Ming-gang LI Ke-dian 《Chinese Quarterly Journal of Mathematics》 CSCD 2010年第4期495-499,共5页
In this paper,spaces with a locally countable sn-network are discussed.It is shown that a space with a locally countable sn-network iff it is an snf-countable space with a locally countable k-network.As its applicatio... In this paper,spaces with a locally countable sn-network are discussed.It is shown that a space with a locally countable sn-network iff it is an snf-countable space with a locally countable k-network.As its application,almost-open and closed mappings(or finite-to-one and closed mapping) preserve locally countable sn-networks,and a perfect preimage theorem on spaces with a locally countable sn-network is established. 展开更多
关键词 locally countable family sn-network K-NETWORK cs-network
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Star-countable Networks and Locally S-Countable Networks
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作者 燕鹏飞 《Northeastern Mathematical Journal》 CSCD 2004年第4期411-414,共4页
The concept of local s-countablity is introduced, and the relations between locally s-countable collections and star-countable collections are discussed.
关键词 locally s-countable star-countable cs-network cs-network
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The Infinity Tree: Representing Infinities of Real Numbers with Countably Infinite Tree Structures
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作者 Philip C. Jackson 《Advances in Pure Mathematics》 2023年第4期198-205,共8页
This paper discusses how the infinite set of real numbers between 0 and 1 could be represented by a countably infinite tree structure which would avoid Cantor’s diagonalization argument that the set of real numbers i... This paper discusses how the infinite set of real numbers between 0 and 1 could be represented by a countably infinite tree structure which would avoid Cantor’s diagonalization argument that the set of real numbers is not countably infinite. Likewise, countably infinite tree structures could represent all real numbers, and all points in any number of dimensions in multi-dimensional spaces. The objective of this paper is not to overturn previous research based on Cantor’s argument, but to suggest that this situation may be treated as a definitional or axiomatic choice. This paper proposes a “non-Cantorian” branch of cardinality theory, representing all these infinities with countably infinite tree structures. This approach would be consistent with the Continuum Hypothesis. 展开更多
关键词 INFINITY countable DIAGONALIZATION Real Numbers Tree Structure Infinity Tree Continuum Hypothesis
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B(LF,ω~2 )-refinability of inverse limits
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作者 XIONG Zhao-hui YANG Ming-quan 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2010年第4期496-502,共7页
Let X be the limit of an inverse system {Xα, παβ, ∧} and and let λ be the cardinal number of A. Assume that each projection πα : X → Xα is an open and onto map and X is A-paracompact. We prove that if each ... Let X be the limit of an inverse system {Xα, παβ, ∧} and and let λ be the cardinal number of A. Assume that each projection πα : X → Xα is an open and onto map and X is A-paracompact. We prove that if each Xα is B(LF, ω^2)-refinable (hereditarily B(LF, ω^2)- refinable), then X is B(LF, ω^2)-refinable (hereditarily B(LF,ω ^2)-refinable). Furthermore, we show that B(LF, ω^2)-refinable spaces can be preserved inversely undcr closed maps. 展开更多
关键词 Inverse limit B(LF ω^2)-refinability hereditary B(LF ω ^2)-refinability.
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Remarks on B(D,λ)-refinability
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作者 葛英 《Northeastern Mathematical Journal》 CSCD 2004年第2期161-166,共6页
In this paper, some equivalent versions of B(D,λ)-refinability are given. One of these equivalent versions, is that a space X is B(D, ωo)-refinable if and only if X is strongly quasi-paracompact. As an application o... In this paper, some equivalent versions of B(D,λ)-refinability are given. One of these equivalent versions, is that a space X is B(D, ωo)-refinable if and only if X is strongly quasi-paracompact. As an application of the above result, the author shows that weak θ-refinability is strictly weaker than strong quasi-paracompactness in T4-spaces, which answers a question posed by Jiang. In addition, the author proves that a weak version of B(D,λ) always implies weak θ-refinability for any λ<ω1, and also give a T4, B(D,ωo)-refinable (=strongly quasi-paracompact) space which is not θ-refinable. 展开更多
关键词 B(D λ)-refinable strongly quasi-paracompact weakθ-refinable weakθ-refinable
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生成式人工智能的算法风险及治理基点 被引量:21
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作者 陈兵 董思琰 《学习与实践》 北大核心 2023年第10期22-31,共10页
分类分级作为我国当前算法治理体系和对生成式人工智能服务监管的共同原则,是应对生成式人工智能算法风险的重要切入点。为应对算法分类分级治理具体标准不明、规范化与体系性不强、具体制度设计与分类分级原则衔接不严谨等问题,应进一... 分类分级作为我国当前算法治理体系和对生成式人工智能服务监管的共同原则,是应对生成式人工智能算法风险的重要切入点。为应对算法分类分级治理具体标准不明、规范化与体系性不强、具体制度设计与分类分级原则衔接不严谨等问题,应进一步推动分类分级与覆盖算法应用全生命周期的治理制度紧密衔接,探索构建以专门性、专业性法律规范为主,其他规范性文件为补充的,兼具稳定性和灵活性的算法治理法律规则体系,实现多元主体协同、制度设计优化、治理工具创新的同频共振,推动生成式人工智能监管落实。 展开更多
关键词 分类分级治理 算法备案 算法安全评估 算法问责 生成式人工智能
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广义L-拓扑空间的可数仿紧性
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作者 张敏 王小霞 刘媛媛 《湖北大学学报(自然科学版)》 CAS 2023年第2期301-304,共4页
将L-拓扑空间中的可数仿紧性引入到广义L-拓扑空间中,研究广义L-拓扑空间中的广义可数仿紧性.基于α-远域族、α-局部有限等概念,利用类比和分析的方法,给出广义L-拓扑空间中广义可数仿紧集的概念,研究其基本性质.并证明了广义可数仿紧... 将L-拓扑空间中的可数仿紧性引入到广义L-拓扑空间中,研究广义L-拓扑空间中的广义可数仿紧性.基于α-远域族、α-局部有限等概念,利用类比和分析的方法,给出广义L-拓扑空间中广义可数仿紧集的概念,研究其基本性质.并证明了广义可数仿紧性具有闭遗传性、弱拓扑不变性等性质,该研究为广义L-拓扑空间的相关理论研究提供一定的参考. 展开更多
关键词 广义L-拓扑空间 可数α-远域族 α-局部有限 广义可数仿紧集
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G-可数紧空间
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作者 刘丽 《扬州大学学报(自然科学版)》 CAS 北大核心 2023年第6期6-9,33,共5页
在一般空间中,在G-方法的基础上,从G-收敛和G-聚点出发,引入了G-可数紧空间,讨论其基本性质,并研究了G-可数紧性与G-序列紧性、可数紧性之间的关系.
关键词 G-方法 G-收敛 G-聚点 G-可数紧
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关于具有Pytkeev∗网空间的注记
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作者 邵辉 刘鑫 《宁德师范学院学报(自然科学版)》 2023年第3期225-228,234,共5页
讨论具有特定Pytkeev^(*)网的空间的度量性质,证明点可数的Pytkeev^(*)网是拟k网,并给出例子说明反之并不成立,从而得到具有点可数Pytkeev^(*)网的M空间是可度量的.最后给出了具有点可数Pytkeev^(*)网的可数紧空间是紧可度量的直接证明.
关键词 拓扑空间 Pytkeev^(*)网 度量空间 点可数
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关于映射的其他覆盖性质(英文) 被引量:2
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作者 陈海燕 张夏苇 +1 位作者 孔庆钊 郑顶伟 《广西大学学报(自然科学版)》 CAS CSCD 2006年第3期190-193,207,共5页
主要定义了可数次仿紧映射,可数亚紧映射以及可数次亚紧映射,进一步将一般拓扑空间的覆盖性质拓展到连续函数上.此外本文还给出了这些映射的一些等价刻画以及它们之间的联系.
关键词 可数次仿紧映射 可数亚紧映射 可数次亚紧映射
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认知域与名词的可数性 被引量:12
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作者 李冀宏 杨玉娟 《外语教学》 CSSCI 北大核心 2008年第4期43-46,共4页
认知语言学认为,人们对每一事体的认知都是以认知域为背景或基体的,而传统语言学中的一个基本信条是名词在概念上是不可定义的。认知语法的奠基者Langacker对此观点提出置疑。他认为从概念上理解,名词标示事物。名词可数性的判断在于其... 认知语言学认为,人们对每一事体的认知都是以认知域为背景或基体的,而传统语言学中的一个基本信条是名词在概念上是不可定义的。认知语法的奠基者Langacker对此观点提出置疑。他认为从概念上理解,名词标示事物。名词可数性的判断在于其勾画出的子域是否被识解为例示辖域中述义范围内的有界性(bounded)。除此之外,它们的区别还可以从同质性(homogeneity),可收缩性(contractibility)及可复制性(replicability)三个方面阐释。 展开更多
关键词 认知域 名词 可数性
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红尾副鳅生物学初步研究 被引量:9
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作者 周中艳 严太明 马恒东 《四川农业大学学报》 CSCD 2007年第3期352-356,共5页
通过对雅安市青衣江段红尾副鳅的可量性状、年龄组成、繁殖特性等生物学进行初步研究。红尾副鳅的体长范围为6.98~15.41cm,体重范围为2.10~21.00g;体重与体长呈显著的幂函数关系:W=0.0184L^2.5112=0.933。年龄可分为5个龄组... 通过对雅安市青衣江段红尾副鳅的可量性状、年龄组成、繁殖特性等生物学进行初步研究。红尾副鳅的体长范围为6.98~15.41cm,体重范围为2.10~21.00g;体重与体长呈显著的幂函数关系:W=0.0184L^2.5112=0.933。年龄可分为5个龄组,以3龄和4龄个体占绝大多数。红尾副鳅雄鱼的体长范围为6.95~15.41 cm,雌鱼体长范围为6.98~13.68cm,体重范围为2.10~17.30g,平均绝对怀卵量为340粒/尾。产卵前期Ⅲ期和Ⅳ期卵巢卵粒半径平均值分别为0.686和1.052nm. 展开更多
关键词 红尾副鳅 生物学 可量性状 繁殖特性
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非线性自回归序列的平稳解及其矩的存在性 被引量:10
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作者 张韧 张绍义 《数学物理学报(A辑)》 CSCD 北大核心 2013年第2期260-266,共7页
用马氏链理论研究函数型随机方差非线性自回归模型平稳分布和矩的存在性,特别是只假设新息序列中的随机变量有密度函数,而不需要有处处为正的密度函数.
关键词 马氏链 非线性时间序列 一致可数可加
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命题逻辑系统中理论的真度概念及其应用 被引量:10
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作者 王国俊 高香妮 《陕西师范大学学报(自然科学版)》 CAS CSCD 北大核心 2009年第5期1-6,共6页
首次在命题逻辑系统中引入理论的真度概念,将公式的真度推广为公式集的真度,从而简化了发散度的概念;进一步得出:当理论Γ相容时,理论的真度与相容度之间的关系为η(Γ)=(1+τ(Γ))/2;在命题逻辑系统C2中,将理论Γ1和Γ2分为六类,分别... 首次在命题逻辑系统中引入理论的真度概念,将公式的真度推广为公式集的真度,从而简化了发散度的概念;进一步得出:当理论Γ相容时,理论的真度与相容度之间的关系为η(Γ)=(1+τ(Γ))/2;在命题逻辑系统C2中,将理论Γ1和Γ2分为六类,分别讨论了各类中理论Γ1、Γ2与Γ1∪Γ2的真度之间的关系. 展开更多
关键词 理论的真度 相容度 发散度 有限 可数
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L—Fuzzy拓扑空间中的可数F紧性与几乎可数F紧性 被引量:7
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作者 蒲义书 陈水利 《纯粹数学与应用数学》 CSCD 1993年第2期47-52,共6页
本文在L—uzzy拓扑空间中引入可数F紧性与几乎可数F紧性的概念,并讨论了它们的性质及其相互关系。
关键词 F紧性 可数F紧性 几乎可数F紧性 LF拓扑空间
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大别山区黄缘闭壳龟的形态生物学种群特征分析(Ⅰ) 被引量:6
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作者 黄斌 陈玉栋 杨艳磊 《信阳师范学院学报(自然科学版)》 CAS 北大核心 2008年第3期404-408,共5页
大别山区黄缘闭壳龟自然种群中,有一种比较常见的体形,其形态生物学特征为,腹甲中部凸起呈倒写的"V"形,背甲与腹甲完全闭合且十分紧密.可量性状研究表明:背甲长/背甲宽、背甲长/腹甲长、背甲宽/腹甲宽的统计分析分别为1.37... 大别山区黄缘闭壳龟自然种群中,有一种比较常见的体形,其形态生物学特征为,腹甲中部凸起呈倒写的"V"形,背甲与腹甲完全闭合且十分紧密.可量性状研究表明:背甲长/背甲宽、背甲长/腹甲长、背甲宽/腹甲宽的统计分析分别为1.37±0.04,1.09±0.02,1.32±0.05;体重与背甲长的回归方程为y=0.0059x+11.3150,背甲长与腹甲长的回归方程为y=0.9828x-1.0602,线性相关极其显著.年龄与体重、体重与背甲宽、背甲长与背甲宽、腹甲长与腹甲宽、背甲宽与腹甲宽存在着比较显著的线性关系.而背甲长与体高(r=0.2469,)、腹甲长与体高(r=0.3178)不存在明显的线性相关性. 展开更多
关键词 大别山区 黄缘闭壳龟 形态生物学 可数性状 可量性状
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