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Contraction Integrated Semigroups and Their Applicationto Continuous-time Markov Chains 被引量:31
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作者 YangRongLI 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2003年第3期605-618,共14页
We introduce the notion of the contraction integrated semigroups and give the Lumber-Phillips characterization of the generator, and also the charaterazied generators of isometric integrated semigroups. For their appl... We introduce the notion of the contraction integrated semigroups and give the Lumber-Phillips characterization of the generator, and also the charaterazied generators of isometric integrated semigroups. For their application, a necessary and sufficient condition for q-matrices Q generating a contraction integrated semigroup is given, and a necessary and sufficient condition for a transition function to be a Feller-Reuter-Riley transition function is also given in terms of its q-matrix. 展开更多
关键词 Keywords Integrated semigroups Contraction integrated semigroups Markov chains Transition functions q matrices Feller Reuter Riley transition functions
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一类非线性波动方程混合问题整体解的存在唯一性 被引量:7
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作者 杜心华 《四川师范大学学报(自然科学版)》 CAS CSCD 1994年第4期35-42,共8页
本文用基于半群和稳定性集的方法,简单地证明了非线性波动方程utt-△u=|u|υ-1u,(υ>1)的混合问题在t∈[0,+∞)上整体解的存在性、唯一性及当t→+∞时的增长性质。
关键词 非线性 波动方程 整体解 混合问题
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一类非线性热传导方程混合问题整体解的存在唯一性 被引量:1
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作者 杨晗 《四川师范大学学报(自然科学版)》 CAS CSCD 1995年第1期92-96,共5页
本文运用半群理论和稳定性集的方法,简单地证明了一类典型非线性热传导方程ut=△=│u│pu的混合问题在t∈[0,∝]时,整体解的存在唯一性以及当t→∝时的增长性质。
关键词 非线性 热传导方程 整体解 混合问题
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The structure of superabundant semigroups 被引量:12
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作者 K.P.Shum 《Science China Mathematics》 SCIE 2004年第5期756-771,共16页
A structure theorem for superabundant semigroups in terms of semilattices of normalized Rees matrix semigroups over some cancellative monoids is obtained. This result not only provides a construction method for supera... A structure theorem for superabundant semigroups in terms of semilattices of normalized Rees matrix semigroups over some cancellative monoids is obtained. This result not only provides a construction method for superabundant semigroups but also generalizes the well-known result of Petrich on completely regular semigroups. Some results obtained by Fountain on abundant semigroups are also extended and strengthened. 展开更多
关键词 superabundant semigroups completely regular semigroups normalized Rees matrix semigroups
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保持一个等价关系的部分变换半群(英文) 被引量:12
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作者 裴惠生 周会娟 《数学进展》 CSCD 北大核心 2009年第1期103-116,共14页
设X是一个集合,|X|≥3.P_X为集合X上所有部分变换构成的半群.设E是集合X的一个等价关系.定义P_E(X)={f∈P_X:■x,y∈domf,(x,y)∈E■(f(x),f(y))∈E}.则P_E(X)作成P_X的一个子半群.本文讨论半群P_E(X)的格林关系和正则性,并研究当等价关... 设X是一个集合,|X|≥3.P_X为集合X上所有部分变换构成的半群.设E是集合X的一个等价关系.定义P_E(X)={f∈P_X:■x,y∈domf,(x,y)∈E■(f(x),f(y))∈E}.则P_E(X)作成P_X的一个子半群.本文讨论半群P_E(X)的格林关系和正则性,并研究当等价关系E满足什么条件时,半群P_E(X)是富足半群. 展开更多
关键词 半群 部分变换 正则元 富足半群 格林关系
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The right dual of left C-rpp semigroups 被引量:6
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作者 GUO YuqiDepartment of Mathematics, Yunnan University, Kunming 650091, China 《Chinese Science Bulletin》 SCIE EI CAS 1997年第19期1599-1603,共5页
SEMIGROUP S is said to be rpp (dually, lpp) if every principal right ideal aS^1(S^1a) of S, re-garded as a right (left)S^1-system, is projective. The semigroup which is both rpp and lpp is said to be abundant. These k... SEMIGROUP S is said to be rpp (dually, lpp) if every principal right ideal aS^1(S^1a) of S, re-garded as a right (left)S^1-system, is projective. The semigroup which is both rpp and lpp is said to be abundant. These kinds of generalized regular semigroups have aroused wideattention. The Green’s,relations (~*-Green’s relations introduced by Pastijn) have formed avery useful tool in study on regular (abundant) semigroups. In order to develop the study onrpp semigroups a step further, we introduced the so-called (1)-Green’s,relation which 展开更多
关键词 rpp semigroups LEFT (right) C-rpp semigroups. (I)-Green’s relations.
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THE ABSTRACT CAUCHY PROBLEM AND A GENERALIZATION OF THE LUMER-PHILLIPS THEOREM 被引量:6
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作者 LI YANGRONG 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 1998年第3期349-358,共10页
For injective, bounded operator C on a Banach space X , the author defines the C -dissipative operator, and then gives Lumer-Phillips characterizations of the generators of quasi-contractive C -semigro... For injective, bounded operator C on a Banach space X , the author defines the C -dissipative operator, and then gives Lumer-Phillips characterizations of the generators of quasi-contractive C -semigroups, where a C -semigroup T(·) is quasi-contractive if ‖T(t)x‖‖Cx‖ for all t0 and x∈X . This kind of generators guarantee that the associate abstract Cauchy problem u′(t,x)=Au(t,x) has a unique nonincreasing solution when the initial data is in C(D(A)) (here D(A) is the domain of A ). Also, the generators of quasi isometric C -semigroups are characterized. 展开更多
关键词 semigroups of operators C-semigroups Dissipative operators Abstract Cauchy problems
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STATIONARY DISTRIBUTION OF A STOCHASTIC SIR MODEL WITH SATURATED INCIDENCE AND ITS ASYMPTOTIC STABILITY 被引量:9
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作者 林玉国 蒋达清 靳曼莉 《Acta Mathematica Scientia》 SCIE CSCD 2015年第3期619-629,共11页
In this article, we consider a stochastic SIR model and show that the distributions of the solutions of the system are absolutely continuous. Furthermore, we analyze long-time behaviour of densities of the distributio... In this article, we consider a stochastic SIR model and show that the distributions of the solutions of the system are absolutely continuous. Furthermore, we analyze long-time behaviour of densities of the distributions of the solution. We prove that the densities can converge in L1 to an invariant density. 展开更多
关键词 Diffusion process Markov semigroups asymptotic stability
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A generalized Clifford theorem of semigroups 被引量:6
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作者 SHUM K.P. 《Science China Mathematics》 SCIE 2010年第4期1097-1101,共5页
A U-abundant semigroup S in which every H-class of S contains an element in the set of projections U of S is said to be a U-superabundant semigroup.This is an analogue of regular semigroups which are unions of groups ... A U-abundant semigroup S in which every H-class of S contains an element in the set of projections U of S is said to be a U-superabundant semigroup.This is an analogue of regular semigroups which are unions of groups and an analogue of abundant semigroups which are superabundant.In 1941,Clifford proved that a semigroup is a union of groups if and only if it is a semilattice of completely simple semigroups.Several years later,Fountain generalized this result to the class of superabundant semigroups.In this paper,we extend their work to U-superabundant semigroups. 展开更多
关键词 CLIFFORD THEOREM UNIONS of GROUPS superabundant semigroups U-abundant semigroups Usuperabundant semigroups
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The structure of L*-inverse semigroups 被引量:4
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作者 REN Xueming & SHUM Karping Department of Mathematics, Xi’an University of Architecture and Technology, Xi’an 710055, China Faculty of Science, The Chinese University of Hong Kong, Hong Kong, China 《Science China Mathematics》 SCIE 2006年第8期1065-1081,共17页
The concepts of L*-inverse semigroups and left wreath products of semigroups are introduced. It is shown that the L*-inverse semigroup can be described as the left wreath product of a type A semigroupΓand a left regu... The concepts of L*-inverse semigroups and left wreath products of semigroups are introduced. It is shown that the L*-inverse semigroup can be described as the left wreath product of a type A semigroupΓand a left regular band B together with a mapping which maps the semigroupΓinto the endomorphism semigroup End(B). This result generalizes the structure theorem of Yamada for the left inverse semigroups in the class of regular semigroups. We shall also provide a constructed example for the L*-inverse semigroups by using the left wreath products. 展开更多
关键词 L*-inverse semigroups type A semigroups left regular bands left wreath products.
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On U-orthodox semigroups 被引量:5
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作者 SHUM Kar Ping 《Science China Mathematics》 SCIE 2009年第2期329-350,共22页
As a generalization of an orthodox semigroup in the class of regular semigroups, a type W semigroup was first investigated by El-Qallali and Fountain. As an analogy of the type W semigroups in the class of abundant se... As a generalization of an orthodox semigroup in the class of regular semigroups, a type W semigroup was first investigated by El-Qallali and Fountain. As an analogy of the type W semigroups in the class of abundant semigroups, we introduce the U-orthodox semigroups. It is shown that the maximum congruence μ contained in on U-orthodox semigroups can be determined. As a consequence, we show that a U-orthodox semigroup S can be expressed by the spined product of a Hall semigroup W U and a V-ample semigroup (T,V). This theorem not only generalizes a known result of Hall-Yamada for orthodox semigroups but also generalizes another known result of El-Qallali and Fountain for type W semigroups. 展开更多
关键词 orthodox semigroups type W semigroups U-orthodox semigroups U-ample semigroups spined products 20M10
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Einstein-Podolsky-Rosen Steering and Nonlocality in Open Quantum Systems
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作者 Abdelaziz Sabik 《Journal of Modern Physics》 2024年第4期462-473,共12页
We investigate the dynamical behavior of quantum steering (QS), Bell nonlocality, and entanglement in open quantum systems. We focus on a two-qubit system evolving within the framework of Kossakowski-type quantum dyna... We investigate the dynamical behavior of quantum steering (QS), Bell nonlocality, and entanglement in open quantum systems. We focus on a two-qubit system evolving within the framework of Kossakowski-type quantum dynamical semigroups. Our findings reveal that the measures of quantumness for the asymptotic states rely on the primary parameter of the quantum model. Furthermore, control over these measures can be achieved through a careful selection of these parameters. Our analysis encompasses various cases, including Bell states, Werner states, and Horodecki states, demonstrating that the asymptotic states can exhibit steering, entanglement, and Bell nonlocality. Additionally, we find that these three quantum measures of correlations can withstand the influence of the environment, maintaining their properties even over extended periods. 展开更多
关键词 Quantum Steering Dynamical semigroups Bell Nonlocality Open Quantum System Asymptotic Dynamics Entanglement
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乘法半群为逆半群的半环 被引量:5
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作者 邵勇 赵宪钟 潘秀娟 《西北大学学报(自然科学版)》 CAS CSCD 北大核心 2006年第3期345-347,共3页
目的求证加法导出是半格、乘法导出是逆半群的半环成为分配格的充要条件。方法加法半群和乘法半群上的偏序以及二者之间的关系。结果给出了该类半环成为分配格的几个等价命题。结论推广了双半格成为分配格的一些结果。
关键词 半群 半环 半格 分配格 偏序关系
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Semigroup of Weakly Continuous Operators Associated to a Generalized Schrödinger Equation
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作者 Yolanda Silvia Santiago Ayala 《Journal of Applied Mathematics and Physics》 2023年第4期1061-1076,共16页
In this work, we prove the existence and uniqueness of the solution of the generalized Schrödinger equation in the periodic distributional space P’. Furthermore, we prove that the solution depends continuously r... In this work, we prove the existence and uniqueness of the solution of the generalized Schrödinger equation in the periodic distributional space P’. Furthermore, we prove that the solution depends continuously respect to the initial data in P’. Introducing a family of weakly continuous operators, we prove that this family is a semigroup of operators in P’. Then, with this family of operators, we get a fine version of the existence and dependency continuous theorem obtained. Finally, we provide some consequences of this study. 展开更多
关键词 semigroups Theory Weakly Continuous Operators Existence of Solution Generalized Schrödinger Equation Distributional Problem Periodic Distributional Space
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Ortho-u-monoids 被引量:4
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作者 Chun Mei GONG Yu Qi GUO K. P. SHUM 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2011年第5期831-844,共14页
In this paper, we study the class of ortho-u-monoids which are generalized orthogroups within the class of E(S)-semiabundant semigroups. After introducing the concept of (-)-Green's relations, and obtaining some ... In this paper, we study the class of ortho-u-monoids which are generalized orthogroups within the class of E(S)-semiabundant semigroups. After introducing the concept of (-)-Green's relations, and obtaining some important properties of (-)-Green's relations and super E(S)-semiabundant semigroups, we have given the semilattice decomposition of ortho-u-monoids and a structure theorem for regular ortho-u-monoids. The main techniques that we used in the study are the (-)-Green's relations, and the semi-spined product of semigroups. 展开更多
关键词 (-)-Green's relations super E(S)-semiabundant semigroups ortho-u-monoids semi-spin- ed products
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关于(n,m)-半群上的格林*关系 被引量:2
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作者 魏鹏莉 朱用文 《山东科学》 CAS 2013年第5期1-5,共5页
本文将格林*关系从普通半群推广到(n,m)-半群上,从而定义富足(n,m)-半群、恰当(n,m)-半群和A型(n,m)-半群,并讨论它们的基本性质,特别地推广了关于Munn-半群的一个定理。
关键词 (n m)半群 格林*关系 富足(n m)-半群 恰当(n m)-半群 A型(n m)-半群
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The translational hull of a strongly right type-A semigroup 被引量:2
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作者 郭小江 郭聿琦 《Science China Mathematics》 SCIE 2000年第1期6-12,共7页
It is proved that the translational hull of a strongly right type-A (C-rpp) semigroup is itself a strongly right type-A(C-rpp) semigroup.
关键词 STRONGLY RIGHT type-A semigroups left (right) TRANSLATIONS translational hulls semilattices.
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BOUNDARY FEEDBACK STABILIZATION OF NONUNIFORM TIMOSHENKO BEAM WITH A TIPLOAD 被引量:5
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作者 YAN QINGXU, FENG DEXING Institute of Systems Science, Academy of Mathematics and Systems Science, Chinese Academy of Sciences, Beijing 100080, China. Institute of Systems Science, Academy of Mathematics and Systems Science, Chinese Academy of Sciences, Be 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2001年第4期485-494,共10页
The boundary stabilization problem of a Timoshenko beam attached with a mass at one end is studied. First, with linear boundary force feedback and moment control simultaneously at the end attached with the load, the e... The boundary stabilization problem of a Timoshenko beam attached with a mass at one end is studied. First, with linear boundary force feedback and moment control simultaneously at the end attached with the load, the energy corresponding to the closed loop system is proven to be exponentially convergent to zero as time t →∞. Then, some counterexamples are given to show that, in other casest the corresponding closed loop system is, in general, not stable asymtotically, let alone exponentially. 展开更多
关键词 Timoshenko beam Boundary feedback control C0 semigroups Exponential stability Multiplier method
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A local version of Hardy spaces associated with operators on metric spaces 被引量:5
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作者 GONG RuMing LI Ji YAN LiXin 《Science China Mathematics》 SCIE 2013年第2期315-330,共16页
Let (X, d, μ) be a metric measure space endowed with a distance d and a nonnegative Borel doubling measure μ. Let L be a second order self-adjoint positive operator on L^2(X). Assume that the semigroup e-^tL gen... Let (X, d, μ) be a metric measure space endowed with a distance d and a nonnegative Borel doubling measure μ. Let L be a second order self-adjoint positive operator on L^2(X). Assume that the semigroup e-^tL generated by -L satisfies the Gaussian upper bounds on L2(X). In this article we study a local version of Hardy space hi (X) associated with L in terms of the area function characterization, and prove their atomic characters. Furthermore, we introduce a Moser type local boundedness condition for L, and then we apply this condition to show that the space hzL(X) can be characterized in terms of the Littlewood-Paley function. Finally, a broad class of applications of these results is described. 展开更多
关键词 local Hardy space non-negative self-adjoint operator semigroups local (1 p)-atoms Moser typelocal boundedness condition space of homogeneous type
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Fourier Transforms of Bounded Bilinear Forms on C*(S1)×C*(S2) of Foundation *-semigroups S1 and S2 被引量:2
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作者 M.LASHKARIZADEH BAMI 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2008年第3期439-454,共16页
The author gives a characterization of the Fourier transforms of bounded bilinear forms on C*(S1)×C*(S2) of two foundation semigroups S1 and S2 in terms of Jordan *-representations, hemimogeneous random fi... The author gives a characterization of the Fourier transforms of bounded bilinear forms on C*(S1)×C*(S2) of two foundation semigroups S1 and S2 in terms of Jordan *-representations, hemimogeneous random fields, and as well as weakly harmonizable random fields of S1 and S2 into Hilbert spaces. 展开更多
关键词 topological semigroups Banach *-algebras REPRESENTATIONS positive-definite functions Fourier transforms bilinear forms
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