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Virasoro李代数的子代数间的同构及生成元 被引量:22
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作者 余德民 卢才辉 《系统科学与数学》 CSCD 北大核心 2008年第1期24-29,共6页
证明了无中心Virasoro李代数的有限维子代数同构的充分必要条件,证明了两个元素d_i,d_j作为生成元的充分必要条件,找出了几组互相同构的无限维真子代数,研究了他们的极大性,单性以及其它性质.
关键词 同构 生成元 单李代数
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企业危机管理过程中的组织学习研究 被引量:9
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作者 芮明杰 张良森 《上海管理科学》 2006年第6期42-45,共4页
本文通过对组织学习与危机管理的关系进行分析发现,组织学习是提高企业整体危机管理能力的关键,危机本身就是非常有效的组织学习机制,并运用企业内部的分形理论,寻找到企业危机“类质同象”现象,从而为组织提供危机学习的对象和题材。
关键词 组织学习 危机周期 分形公司 类质同象
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《红楼梦》词汇与现代词汇的词义比较研究 被引量:1
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作者 王绍新 《语言教学与研究》 CSSCI 北大核心 2002年第3期7-13,共7页
本文对《红楼梦》词汇与现代汉语词汇中的同形词词义进行比较 ,意在观察二百多年来近、现代汉语词义演变之大略。两者的同形词词义有如下几种关系 :(1 )基本同义 ;(2 )所指不同 ;(3 )词义抽象、概括的程度不同 ;(4 )非理性意义不同 ;(5... 本文对《红楼梦》词汇与现代汉语词汇中的同形词词义进行比较 ,意在观察二百多年来近、现代汉语词义演变之大略。两者的同形词词义有如下几种关系 :(1 )基本同义 ;(2 )所指不同 ;(3 )词义抽象、概括的程度不同 ;(4 )非理性意义不同 ;(5)所含词义单位不同。 展开更多
关键词 《红楼梦》 现代词汇 词义比较 同形词 非理性意义
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保持斜ξ-Lie零积的可加映射 被引量:6
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作者 齐霄霏 侯晋川 崔建莲 《中国科学:数学》 CSCD 北大核心 2015年第2期151-165,共15页
令H与K是维数大于2的复Hilbert空间,ξ∈C.假设Φ:B(H)→B(K)是满足对任意A,B∈B(H)都有AB=ξBA*Φ(A)Φ(B)=ξΦ(B)Φ(A)*的可加满射.本文证明了,(1)如果ξ=1,则存在酉或反酉算子U:H→K以及非零实数c使得Φ(A)=c UAU*对所有A∈B(H)成... 令H与K是维数大于2的复Hilbert空间,ξ∈C.假设Φ:B(H)→B(K)是满足对任意A,B∈B(H)都有AB=ξBA*Φ(A)Φ(B)=ξΦ(B)Φ(A)*的可加满射.本文证明了,(1)如果ξ=1,则存在酉或反酉算子U:H→K以及非零实数c使得Φ(A)=c UAU*对所有A∈B(H)成立;(2)如果ξ∈R\{1}且Φ保单位元,则存在酉或反酉算子U:H→K使得Φ(A)=UAU*对所有A∈B(H)成立;(3)如果ξ∈C\R且Φ保单位元,则存在酉算子U:H→K使得Φ(A)=UAU*对所有A∈B(H)成立. 展开更多
关键词 Hilebert空间上的算子 可加映射 斜Lie积 *-同构
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Eventually homological isomorphisms and Gorenstein projective modules
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作者 Yongyun Qin Dawei Shen 《Science China Mathematics》 SCIE CSCD 2024年第8期1719-1734,共16页
We prove that a certain eventually homological isomorphism between module categories induces triangle equivalences between their singularity categories,Gorenstein defect categories and stable categories of Gorenstein ... We prove that a certain eventually homological isomorphism between module categories induces triangle equivalences between their singularity categories,Gorenstein defect categories and stable categories of Gorenstein projective modules.Furthermore,we show that the Auslander-Reiten conjecture and the Gorenstein symmetry conjecture can be reduced by eventually homological isomorphisms.Applying these results to arrow removal and vertex removal,we describe the Gorenstein projective modules over some non-monomial algebras and verify the Auslander-Reiten conjecture for certain algebras. 展开更多
关键词 singularity categories Gorenstein defect categories Gorenstein projective modules AuslanderReiten conjecture Gorenstein symmetry conjecture eventually homological isomorphisms
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标准算子代数上完全保斜幂等性的可加映射 被引量:6
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作者 黄丽 路召飞 李俊林 《中北大学学报(自然科学版)》 CAS 北大核心 2011年第1期71-73,共3页
在完全保持幂等性映射研究的基础上,利用算子代数的方法讨论了无限维实或复Banach空间上的标准算子代数上完全保持幂等性的可加映射的刻画问题.通过将问题划归为秩-幂等元集上双边保持零积的映射的刻画问题,证明了标准算子代数上完全保... 在完全保持幂等性映射研究的基础上,利用算子代数的方法讨论了无限维实或复Banach空间上的标准算子代数上完全保持幂等性的可加映射的刻画问题.通过将问题划归为秩-幂等元集上双边保持零积的映射的刻画问题,证明了标准算子代数上完全保持斜幂等性的可加映射是同构或(复情形)共轭同构. 展开更多
关键词 泛函分析 标准算子代数 完全保持问题 斜幂等性 同构
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Linear Maps Preserving Idempotence on Nest Algebras 被引量:3
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作者 JianLianCUI JinChuanHOU 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2004年第5期807-820,共14页
In this paper,we discuss the rank-1-preserving linear maps on nest algebras of Hilbert- space operators.We obtain several characterizations of such linear maps and apply them to show that a weakly continuous linear bi... In this paper,we discuss the rank-1-preserving linear maps on nest algebras of Hilbert- space operators.We obtain several characterizations of such linear maps and apply them to show that a weakly continuous linear bijection on an atomic nest algebra is idempotent preserving if and only if it is a Jordan homomorphism,and in turn,if and only if it is an automorphism or an anti-automorphism. 展开更多
关键词 Nest algebras Rank-1 operators Idempotent operators Jordan isomorphisms
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危机管理的类型学分析 被引量:5
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作者 黄书亭 《科技和产业》 2008年第9期78-83,共6页
运用类型学的思想方法,以西方管理历史为宏观背景,联系杰出CEO的危机管理实践,从多学科的角度,对管理史、企业环境、利益集团、企业战略、社会责任、CEO的特征与作用,对危机管理概念、理论、方法和实践,进行多层面的分析和透视,得出有... 运用类型学的思想方法,以西方管理历史为宏观背景,联系杰出CEO的危机管理实践,从多学科的角度,对管理史、企业环境、利益集团、企业战略、社会责任、CEO的特征与作用,对危机管理概念、理论、方法和实践,进行多层面的分析和透视,得出有关结论,丰富危机管理的理论宝库。 展开更多
关键词 类型 管理CEO 环境 社会责任 类质同象
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Additive Maps Between Standard Operator Algebras Compressing Certain Spectral Functions 被引量:2
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作者 Jin Chuan HOU 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2008年第12期2041-2048,共8页
We characterize the surjective additive maps compressing the spectral function Δ(·) between standard operator algebras acting on complex Banach spaces, where Δ(·) stands for any one of nine spectral fu... We characterize the surjective additive maps compressing the spectral function Δ(·) between standard operator algebras acting on complex Banach spaces, where Δ(·) stands for any one of nine spectral functions σ(·), σl(·), σr(·),σl(·) ∩ σr(·), δσ(·), ησ(·), σap(·), σs(·), and σap(·) ∩ σs(·). 展开更多
关键词 additive maps standard operator algebras spectral functions isomorphisms
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ISOMORPHISMS BETWEEN ENDOMORPHISM RINGS OF FREE MODULES
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作者 许永华 《Science China Mathematics》 SCIE 1992年第7期769-779,共11页
In this paper we give the following main results: (ⅰ) Let F(?) and G(?) be two free modules. Then F(?) and G(?) are semi-linearly isomorphic if and only if End F(?) and End G(?) are strictly isomorphic. (ⅱ) We give ... In this paper we give the following main results: (ⅰ) Let F(?) and G(?) be two free modules. Then F(?) and G(?) are semi-linearly isomorphic if and only if End F(?) and End G(?) are strictly isomorphic. (ⅱ) We give a new method to generalize the Bolla theorem in 1985 which gave a categorical description for isomorphism between End F(?) and End G(?). (ⅲ) The Wolfson theorem is a corollary of our theorem. 展开更多
关键词 free modules SEMI-LINEAR isomorphisms ENDOMORPHISMS STRICT isomorphisms CATEGORY equivalence.
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完全保持不同因子交换性的映射 被引量:3
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作者 刘艳晓 黄丽 《太原科技大学学报》 2015年第3期237-240,共4页
刻画了实或复的无限维Banch空间上的标准算子代数间完全保持不同因子交换性的一般映射,证明了这样的映射是同构的常数倍或(复的情形下)共轭同构的常数倍。
关键词 标准算子代数 完全保持问题 不同因子交换 同构
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标准算子代数上完全保对合性的可加映射 被引量:3
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作者 黄丽 刘敏 《数学的实践与认识》 CSCD 北大核心 2012年第10期156-162,共7页
刻画了无限维实或复Banach空间上的标准算子代数间完全保对合性的可加映射,证明了这样的映射是同构的常数倍或(复情形下)共轭同构的常数倍.
关键词 标准算子代数 完全保持问题 对合性 可加映射 同构
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On Maps Preserving Unitarily Invariant Norms of the Spectral Geometric Mean
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作者 Hongjie Chen Lei Li +1 位作者 Zheng Shi Liguang Wang 《Journal of Applied Mathematics and Physics》 2021年第4期577-583,共7页
We consider maps on positive definite cones of von Neumann algebras preserving unitarily invariant norms of the spectral geometric means. The main results concern Jordan *-isomorphisms between <em>C</em>*-... We consider maps on positive definite cones of von Neumann algebras preserving unitarily invariant norms of the spectral geometric means. The main results concern Jordan *-isomorphisms between <em>C</em>*-algebras, and show that they are characterized by the preservation of unitarily invariant norms of those operations. 展开更多
关键词 Spectral Geometric Mean Positive Cone Jordan *-isomorphisms Unitarily Invariant Norm
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Lifting of Isomorphisms Between Elementary Linear Groups
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作者 李福安 《Chinese Science Bulletin》 SCIE EI CAS 1993年第14期1158-1162,共5页
Let R and A be commutative rings with identity, and m and n be integers ≥3. Consider when and how an isomorphism E_m(R)E_n(A) can be lifted to an isomorphism between the corresponding Steinberg groups. It was proved ... Let R and A be commutative rings with identity, and m and n be integers ≥3. Consider when and how an isomorphism E_m(R)E_n(A) can be lifted to an isomorphism between the corresponding Steinberg groups. It was proved that, if E_m(R) is isomorphic to E_n(A) then m=n (cf. Ref. [1]). When n≥4, every isomorphism E_n(R)E_n(A) is of the standard type, and it can be naturally and uniquely lifted to an isomorphism from St_n(R) to St_n(A) (cf. Refs. [1] and [2]). However, the case n=3 is different from that n≥4, 展开更多
关键词 linear GROUPS Steinberg GROUPS isomorphisms Dennis-Stein symbols.
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Isomorphic Commutative Group Algebras of p-Mixed Warfield Groups
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作者 PeterV.DANCHEV 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2005年第4期913-916,共4页
Let G be a p-mixed Warfield Abelian group and F a field of char F = p ≠ 0. It is proved that if for any group H the group algebras FH and FG are F-isomorphic, then H is isomorphic to G. This presentation enlarges a r... Let G be a p-mixed Warfield Abelian group and F a field of char F = p ≠ 0. It is proved that if for any group H the group algebras FH and FG are F-isomorphic, then H is isomorphic to G. This presentation enlarges a result of W. May argued when G is p-local Warfield Abelian and published in Proc. Amer. Math. Soc. (1988). 展开更多
关键词 p-mixed Warfield groups Isotype subgroups Heights Bases isomorphisms
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Multiplicative Mappings of Rings
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作者 Fang Yan LU Jin Hai XIE 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2006年第4期1017-1020,共4页
Let R and F be arbitrary associative rings. A mapping φ of R onto F is called a multiplicative isomorphism if φ is bijective and satisfies φ(xy) = φ(x)φ(y) for all x, y ∈ R. In this short note, we establis... Let R and F be arbitrary associative rings. A mapping φ of R onto F is called a multiplicative isomorphism if φ is bijective and satisfies φ(xy) = φ(x)φ(y) for all x, y ∈ R. In this short note, we establish a condition on R, in the case where R may not contain any non-zero idempotents, that assures that φ is additive, which generalizes the famous Martindale's result. As an application, we show that under a mild assumption every multiplicative isomorphism from the radical of a nest algebra onto an arbitrary ring is additive. 展开更多
关键词 Multiplicative isomorphisms ADDITIVITY IDEMPOTENTS
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Approximate (m, n)-Cauchy-Jensen Additive Mappings in C^*-algebras
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作者 John Michael RASSIAS Kil Woung JUN Hark-Mahn KIM 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2011年第10期1907-1922,共16页
Concerning the stability problem of functional equations, we introduce a general (m, n)- Cauchy-Jensen functional equation and establish new theorems about the Hyers-Ulam stability of general (m, n)-Cauchy Jensen ... Concerning the stability problem of functional equations, we introduce a general (m, n)- Cauchy-Jensen functional equation and establish new theorems about the Hyers-Ulam stability of general (m, n)-Cauchy Jensen additive mappings in C^*-algebras, which generalize the result's obtained for Cauchy-Jensen type additive mappings. 展开更多
关键词 Generalized Hyers Ulam stability (m n)-Cauchy-Jensen mappings unitary group C^*- algebra isomorphisms DERIVATIONS
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ISOMETRIC ISOMORPHISMS OF TRIANGULAR BANACH ALGEBRAS
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作者 LuoJianwen LuFangyan 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2000年第4期403-408,共6页
Let A and B be Banach algebras.Let M be a Banach A,B module with bounded 1.Then T=AM 0B is a Banach algebra with the usual operations and the norm AM 0B=‖A‖+‖M‖+‖B‖.Such an algebra is called a triangular Bana... Let A and B be Banach algebras.Let M be a Banach A,B module with bounded 1.Then T=AM 0B is a Banach algebra with the usual operations and the norm AM 0B=‖A‖+‖M‖+‖B‖.Such an algebra is called a triangular Banach algebra.In this paper the isometric isomorphisms of triangular Banach algebras are characterized. 展开更多
关键词 Triangualr Banach algebras isometric isomorphisms.
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与广义Cartan K型李代数有关的一类无限维李代数 被引量:1
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作者 张子龙 张更生 贾雨亭 《系统科学与数学》 CSCD 北大核心 2003年第1期86-93,共8页
本文主要引入了一类与广义Cartan K型李代数有关的无限维李代数,并讨论了 它的单性及任两个这类李代数的同构问题.
关键词 广义CartanK型李代数 单李代数 同构
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Characterization of Lie multiplicative isomorphisms between nest algebras 被引量:2
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作者 QI XiaoFei HOU JinChuan 《Science China Mathematics》 SCIE 2011年第11期2453-2462,共10页
Let N and M be nests on Banach spaces X and Y over the real or complex field F, respectively, with the property that if M ∈ M such that M_ =M, then M is complemented in Y. Let AlgN and AlgM be the associated nest alg... Let N and M be nests on Banach spaces X and Y over the real or complex field F, respectively, with the property that if M ∈ M such that M_ =M, then M is complemented in Y. Let AlgN and AlgM be the associated nest algebras. Assume that Ф : AlgN → AlgM is a bijective map. It is proved that, if dim X = ∞ and if there is a nontrivial element in N which is complemented in X, then Ф is Lie multiplicative (i.e. Ф([A, B]) = [Ф(A), Ф(B)] for all A, B ∈ AlgN) if and only if Ф has the form Ф(A) = TAT^-1 + τ(A) for all A ∈ AlgAN or Ф(A) = -TA^*T^-1 + τ(A) for all A ∈ AlgN, where T is an invertible linear or conjugate linear operator and τ : AlgN →FI is a map with τ([A, B]) = 0 for all A, B ∈ AlgN. The Lie multiplicative maps are also characterized for the case dim X 〈 ∞. 展开更多
关键词 Banach spaces nest algebras Lie ring isomorphisms Lie multiplicative maps
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