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A Set of Almost Automorphic Functions and Applications
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作者 William Dimbour Vincent Valmorin 《Applied Mathematics》 2024年第1期9-21,共13页
For a set S of real numbers, we introduce the concept of S-almost automorphic functions valued in a Banach space. It generalizes in particular the space of Z-almost automorphic functions. Considering the space of S-al... For a set S of real numbers, we introduce the concept of S-almost automorphic functions valued in a Banach space. It generalizes in particular the space of Z-almost automorphic functions. Considering the space of S-almost automorphic functions, we give sufficient conditions of the existence and uniqueness of almost automorphic solutions of a differential equation with a piecewise constant argument of generalized type. This is done using the Banach fixed point theorem. 展开更多
关键词 almost Automorphic Functions S-almost Automorphic Functions Differential Equation with Piecewise Constant Argument of Generalized Type
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Pseudo Almost Periodic Solutions of Nonlinear Hyperbolic Equations with Piecewise Constant Argument 被引量:1
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作者 周红燕 朴大雄 《Northeastern Mathematical Journal》 CSCD 2007年第6期491-504,共14页
In this paper, we investigate the pseudo almost periodicity of the unique bounded solution for a nonlinear hyperbolic equation with piecewise constant argument. The equation under consideration is a mathematical model... In this paper, we investigate the pseudo almost periodicity of the unique bounded solution for a nonlinear hyperbolic equation with piecewise constant argument. The equation under consideration is a mathematical model for the dynamics of gas absorption, 展开更多
关键词 uniformly almost periodic function uniformly pseudo almost periodicfunction uniformly almost periodic sequence uniformly pseudo almost periodic se-quence fixed point Method
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Almost Sure Convergence of Proximal Stochastic Accelerated Gradient Methods
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作者 Xin Xiang Haoming Xia 《Journal of Applied Mathematics and Physics》 2024年第4期1321-1336,共16页
Proximal gradient descent and its accelerated version are resultful methods for solving the sum of smooth and non-smooth problems. When the smooth function can be represented as a sum of multiple functions, the stocha... Proximal gradient descent and its accelerated version are resultful methods for solving the sum of smooth and non-smooth problems. When the smooth function can be represented as a sum of multiple functions, the stochastic proximal gradient method performs well. However, research on its accelerated version remains unclear. This paper proposes a proximal stochastic accelerated gradient (PSAG) method to address problems involving a combination of smooth and non-smooth components, where the smooth part corresponds to the average of multiple block sums. Simultaneously, most of convergence analyses hold in expectation. To this end, under some mind conditions, we present an almost sure convergence of unbiased gradient estimation in the non-smooth setting. Moreover, we establish that the minimum of the squared gradient mapping norm arbitrarily converges to zero with probability one. 展开更多
关键词 Proximal Stochastic Accelerated Method almost Sure Convergence Composite Optimization Non-Smooth Optimization Stochastic Optimization Accelerated Gradient Method
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ASYMPTOTIC BEHAVIOR FOR COMMUTATIVE SEMIGROUPS OF ALMOST ASYMPTOTICALLY NONEXPANSIVE TYPE MAPPINGS 被引量:1
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作者 曾六川 《Acta Mathematica Scientia》 SCIE CSCD 2006年第2期246-254,共9页
This article introduces the concept of commutative semigroups of almost asymptotically nonexpansive-type mappings in a Banach space X which has the Opial property and whose norm is UKK, and establishes the weak conver... This article introduces the concept of commutative semigroups of almost asymptotically nonexpansive-type mappings in a Banach space X which has the Opial property and whose norm is UKK, and establishes the weak convergence theorems for almostorbits of this class of commutative semigroups. The author improves, extends and develops some recent and earlier results. 展开更多
关键词 Semitopological semigroup almost asymptotically nonexpansive type mapping almost orbit asymptotic behavior
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ALMOST PERIODICITY AND EQUICONTINUITY OF THE TOPOLOGICAL TRANSFORMATION GROUP 被引量:1
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作者 Li Zhicong Li Juntao 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2006年第4期467-472,共6页
In this paper, a characterization of almost periodicity of topological transformation groups on uniform spaces is given. By searching the appropriate base for uniform structure, it is shown that the topological transf... In this paper, a characterization of almost periodicity of topological transformation groups on uniform spaces is given. By searching the appropriate base for uniform structure, it is shown that the topological transformation group is topologically equivalent to an isometric one if it is uniformly equicontinuous. 展开更多
关键词 uniform space topological transformation group EQUICONTINUITY almost periodicity compactly almost periodicity.
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TAUBERIAN THEOREMS FOR WEAK ALMOST CONVERGENT FUNCTIONS
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作者 Meng-Kuang Kuo 《Acta Mathematica Scientia》 SCIE CSCD 2011年第3期1203-1212,共10页
The almost convergent function which was introduced by Raimi [6] and discussed by Ho [4], Das and Nanda [2, 3], is the continuous analogue of almost convergent sequences (see [5]). In this paper, we establish the Ta... The almost convergent function which was introduced by Raimi [6] and discussed by Ho [4], Das and Nanda [2, 3], is the continuous analogue of almost convergent sequences (see [5]). In this paper, we establish the Tauberian conditions and the Cauchy criteria for weak almost convergent functions on R2+ . 展开更多
关键词 almost convergent functions weak almost convergent functions Tauberian theorems Cauchy criterions
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ON ALMOST PRECOVERS AND ALMOST PREENVELOPES
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作者 毛立新 丁南庆 佟文廷 《Acta Mathematica Scientia》 SCIE CSCD 2006年第3期395-400,共6页
Let C be a class of R-modules closed under isomorphisms and finite direct sums. It is first shown that the finite direct sum of almost C-precovers is an almost C-precover and the direct sum of an almost C-cover and a ... Let C be a class of R-modules closed under isomorphisms and finite direct sums. It is first shown that the finite direct sum of almost C-precovers is an almost C-precover and the direct sum of an almost C-cover and a weak C-cover is a weak C-cover. Then the notion of almost C-preenvelopes is introduced and studied. 展开更多
关键词 almost precover almost preenvelope
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Inverse limits of hereditarily almost expandable class
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作者 ZHAO Bin 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2009年第2期237-244,共8页
In this paper, the hereditarily almost expandability of inverse limits is investigated, with two results obtained. Let X be the inverse limit space of an inverse system (Xα, π^αβ, ∧}. (1) Suppose X is heredita... In this paper, the hereditarily almost expandability of inverse limits is investigated, with two results obtained. Let X be the inverse limit space of an inverse system (Xα, π^αβ, ∧}. (1) Suppose X is hereditarily κ-metacompact, if each Xα is hereditarily pointwise collectionwise normal (almost θ-expandable, almost discrete θ-expandable), then so is X; (2) Suppose X is hereditarily κ-σ-metacompact, if each Xα is hereditarily almost σ-expandable (almost discrete σ-expandable = σ-pointwise collectionwise normal), then so is X. 展开更多
关键词 inverse limit space κ-metacompactness κ-σ-metacompactness hereditarily pointwise collection- wise normal hereditarily almost θ-expandable hereditarily almost σ-expandable
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Almost Fuzzy Compactness in L-fuzzy Topological Spaces
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作者 Li Hong-yan Cui Wei Lei Feng-chun 《Communications in Mathematical Research》 CSCD 2015年第3期267-273,共7页
In this paper, the notion of almost fuzzy compactness is dened in L-fuzzy topological spaces by means of inequality, where L is a completely distributiveDeMorgan algebra. Its properties are discussed and many characte... In this paper, the notion of almost fuzzy compactness is dened in L-fuzzy topological spaces by means of inequality, where L is a completely distributiveDeMorgan algebra. Its properties are discussed and many characterizations of it arepresented. 展开更多
关键词 L-fuzzy topological space L-fuzzy almost compactness L-fuzzy compactness almost fuzzy compactness
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Note on Almost Hermitian Manifolds
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作者 朱鹏 《Northeastern Mathematical Journal》 CSCD 2008年第4期373-376,共4页
We give a necessary and sufficient condition for an almost Hermitian manifold to be a Kahler manifold. By making use of this condition, we give a new proof of Goldberg's theorem.
关键词 INTEGRABILITY almost Hermitian manifold almost Kahler manifold Kahler manifold
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Existence and global attractivity of unique positive almost periodic solution for a model of hematopoiesis 被引量:7
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作者 YANG Xi-tao 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2010年第1期25-34,共10页
Sufficient conditions are obtained which guarantee the uniform persistence and global attractivity of solutions for the model of hematopoiesis. Then some criteria are established for the existence, uniqueness and glob... Sufficient conditions are obtained which guarantee the uniform persistence and global attractivity of solutions for the model of hematopoiesis. Then some criteria are established for the existence, uniqueness and global attractivity of almost periodic solutions of almost periodic system. 展开更多
关键词 almost periodicity global attractivity uniform persistence.
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OD-CHARACTERIZATION OF ALMOST SIMPLE GROUPS RELATED TO U_6(2) 被引量:4
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作者 张良才 施武杰 《Acta Mathematica Scientia》 SCIE CSCD 2011年第2期441-450,共10页
Let G be a finite group and π(G) = {pl,p2,…… ,pk} be the set of the primes dividing the order of G. We define its prime graph F(G) as follows. The vertex set of this graph is 7r(G), and two distinct vertices ... Let G be a finite group and π(G) = {pl,p2,…… ,pk} be the set of the primes dividing the order of G. We define its prime graph F(G) as follows. The vertex set of this graph is 7r(G), and two distinct vertices p, q are joined by an edge if and only if pq ∈ πe(G). In this case, we write p - q. For p ∈π(G), put deg(p) := |{q ∈ π(G)|p - q}|, which is called the degree of p. We also define D(G) := (deg(p1), deg(p2),..., deg(pk)), where pl 〈 p2 〈 -……〈 pk, which is called the degree pattern of G. We say a group G is k-fold OD-characterizable if there exist exactly k non-isomorphic finite groups with the same order and degree pattern as G. Specially, a l-fold OD-characterizable group is simply called an OD-characterizable group. Let L := U6(2). In this article, we classify all finite groups with the same order and degree pattern as an almost simple groups related to L. In fact, we prove that L and L.2 are OD-characterizable, L.3 is 3-fold OD-characterizable, and L.S3 is 5-fold OD-characterizable. 展开更多
关键词 almost simple group prime graph degree of a vertex degree pattern
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Almost perfect sequences based on cyclic difference sets 被引量:6
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作者 Chen Gang Zhao Zhengyu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2007年第1期155-159,共5页
The perfect sequences are so ideal that all out-of-phase autocorrelation coefficients are zero, and if the sequences are used as the coding modulating signal for the phase-modulated radar, there will be no interferenc... The perfect sequences are so ideal that all out-of-phase autocorrelation coefficients are zero, and if the sequences are used as the coding modulating signal for the phase-modulated radar, there will be no interference of side lobes theoretically. However, it has been proved that there are no binary perfect sequences of period 4 〈 n ≤ 12100. Hence, the almost perfect sequences with all out-of-phase autocorrelation coefficients as zero except one are of great practice in engineering. Currently, the cyclic difference set is one of most effective tools to analyze the binary sequences with perfect periodic autocorrelation function. In this article, two characteristic formulas corresponding to the autocorrelation and symmetric structure of almost perfect sequences are calculated respectively. All almost perfect sequences with period n, which is a multiple of 4, can be figured out by the two formulas. Several almost perfect sequences with different periods have been hunted by the program based on the two formulas and then applied to the simulation program and practical application for ionospheric sounding. 展开更多
关键词 Perfect sequence almost perfect sequence Cyclic difference sets Autocorrelation coefficients Side lobes Ionospheric sounding
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ALMOST PERIODIC SOLUTION OF ONE DIMENSIONAL VISCOUS CAMASSA-HOLM EQUATION 被引量:4
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作者 付一平 郭柏灵 《Acta Mathematica Scientia》 SCIE CSCD 2007年第1期117-124,共8页
This article studies one dimensional viscous Camassa-Holm equation with a periodic boundary condition. The existence of the almost periodic solution is investigated by using the Galerkin method.
关键词 Viscous Camassa-Holm equation almost periodic solution EXISTENCE
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Almost sure central limit theory for products of sums of partial sums 被引量:6
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作者 WU Qun-ying 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2012年第2期169-180,共12页
Consider a sequence of i.i.d.positive random variables.An universal result in almost sure limit theorem for products of sums of partial sums is established.We will show that the almost sure limit theorem holds under a... Consider a sequence of i.i.d.positive random variables.An universal result in almost sure limit theorem for products of sums of partial sums is established.We will show that the almost sure limit theorem holds under a fairly general condition on the weight dk= k-1 exp(lnβk),0≤β〈1.And in a sense,our results have reached the optimal form. 展开更多
关键词 almost sure central limit theorem WEIGHT product of sums of partial sums.
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EXISTENCE AND ATTRACTIVITY OF k-ALMOST AUTOMORPHIC SEQUENCE SOLUTION OF A MODEL OF CELLULAR NEURAL NETWORKS WITH DELAY 被引量:3
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作者 Syed ABBAS 夏永辉 《Acta Mathematica Scientia》 SCIE CSCD 2013年第1期290-302,共13页
In this paper we discuss the existence and global attractivity of k-almost automorphic sequence solution of a model of cellular neural networks. We consider the corresponding difference equation analogue of the model ... In this paper we discuss the existence and global attractivity of k-almost automorphic sequence solution of a model of cellular neural networks. We consider the corresponding difference equation analogue of the model system using suitable discretization method and obtain certain conditions for the existence of solution. Almost automorphic function is a good generalization of almost periodic function. This is the first paper considering such solutions of the neural networks. 展开更多
关键词 almost automorphic sequence difference equations neural networks
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关于Weakly Almost Clean环(英文)
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作者 孟文静 陈焕艮 《杭州师范大学学报(自然科学版)》 CAS 2015年第4期418-422,共5页
定义了weakly almost clean环.交换环R叫做weakly almost clean环,如果对于任意一个元素x∈R可以写成x=r+e或x=r-e的形式,其中r∈reg(R)且e∈Id(R).首先,对于环Ri的非空集合{Ri},证明了直和R=∏i∈IRi为weakly almost clean当且仅当存在... 定义了weakly almost clean环.交换环R叫做weakly almost clean环,如果对于任意一个元素x∈R可以写成x=r+e或x=r-e的形式,其中r∈reg(R)且e∈Id(R).首先,对于环Ri的非空集合{Ri},证明了直和R=∏i∈IRi为weakly almost clean当且仅当存在m∈I使Rm为weakly almost clean且对所有的n≠m,Rn为almost clean.然后,设R是一个环且M为一个R-模,得到了R和M的平凡扩张R(M)为weakly almost clean当且仅当每个x∈R可以写成x=r+e或x=r-e的形式,其中r∈R-(Z(R)∪Z(M))且e∈Id(R).进而推广了almost clean环的相应结果. 展开更多
关键词 CLEAN环 零因子 正则元 幂等元 almost CLEAN环
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低位直肠癌新辅助治疗达到almost-cCR(near-cCR)的缩小手术和根治术疗效的对照研究 被引量:3
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作者 陆海涛 刘信 +9 位作者 石刚 李继彬 闫晓菲 郭瑞 张庆彤 赵建峰 刘放 王茜 孙德宇 张睿 《现代肿瘤医学》 CAS 2019年第16期2900-2904,共5页
目的:总结低位直肠癌行新辅助治疗原发肿瘤达到almost-cCR(almost-clinical complete response)后,比较缩小手术和根治术两种术式的优缺点。方法:回顾性分析2013年1月至2018年10月间,辽宁省肿瘤医院大肠科收治的局部晚期低位直肠癌经新... 目的:总结低位直肠癌行新辅助治疗原发肿瘤达到almost-cCR(almost-clinical complete response)后,比较缩小手术和根治术两种术式的优缺点。方法:回顾性分析2013年1月至2018年10月间,辽宁省肿瘤医院大肠科收治的局部晚期低位直肠癌经新辅助治疗原发肿瘤达到almost-cCR(near-cCR)的共35例患者的临床和病理资料。采用Kaplan-Meier法绘制生存曲线。结果:35例病人中,缩小手术组共纳入9例患者,根治术组共纳入26例患者。缩小手术组未出现术后并发症,根治术组3例患者出现术后并发症,发生率11.5%。缩小手术组1年和2年无复发生存率均为100%。根治术组1年和2年无复发生存率分别为96.1%和88.4%。缩小手术组中位DFS和OS均为32.1个月。根治术组中位DFS和OS分别为43.2个月和39.6个月。结论:对于低位直肠癌新辅助治疗达到almost-cCR(near-cCR)的病人,缩小手术组可以取得不亚于根治术组的临床疗效。并且减少手术创伤,改善近期疗效和远期预后。 展开更多
关键词 低位直肠癌 新辅助治疗 临床缓解 缩小手术
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Existence of asymptotically almost periodic solutions and stability properties for functional difference equations 被引量:4
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作者 吴中华 《Journal of Chongqing University》 CAS 2012年第2期97-102,共6页
For functional difference equations with unbounded delay,we characterized the existence of totally stable and asymptotically almost periodic solution by using stability properties of a bounded solution in a certain li... For functional difference equations with unbounded delay,we characterized the existence of totally stable and asymptotically almost periodic solution by using stability properties of a bounded solution in a certain limiting equation. 展开更多
关键词 functional difference equations asymptotically almost periodic solutions total stability properties
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Asymptotic Behavior of Almost-orbits of Asymptotically Nonexpansive Semigroups in Banach Spaces(Dedicated to Professor You Zhaoyong for his 60th brithday)
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作者 Xu Hong-KunInstitute of Applied Mathematics, East China University of Chemical Technology, Changhai 200237, China 《工程数学学报》 CSCD 1991年第2期19-30,共12页
Let C be a closed bounded convex subset of a uniformaly convex Banach space X with a Frechet differentiable norm, F= {T(t):t ≥0} an asymptotically noncxpansivc semigroup on C, and u:[0,∞)→ C an almost-orbit of F. T... Let C be a closed bounded convex subset of a uniformaly convex Banach space X with a Frechet differentiable norm, F= {T(t):t ≥0} an asymptotically noncxpansivc semigroup on C, and u:[0,∞)→ C an almost-orbit of F. Then we show that {u(t):t ≥ 0} is almost convergent weakly to a common fixed point y of F, that isweak - lim1/tdr - y uniformly in s≥ 0.This implies that {u(t):t≥ 0} converges weakly to y if and onlyif u is weakly asymptotically regular, i.e lim (u(t + s) - u(t) = 0 weakly for all s≥ 0. 展开更多
关键词 almost-orbit ASYMPTOTICALLY NONEXPANSIVE SEMIGROUP almost convergence fixed point NONEXPANSIVE retraction.
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