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Representations of the Drazin inverse involving idempotents in a ring 被引量:1
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作者 朱辉辉 陈建龙 《Journal of Southeast University(English Edition)》 EI CAS 2015年第3期427-430,共4页
An element a of a ring R is called Drazin invertible if there exists b∈R such that ab =ba,bab =b,and a -a2 b is nilpotent.The element b above is unique if it exists and is denoted as aD .The equivalent conditions of ... An element a of a ring R is called Drazin invertible if there exists b∈R such that ab =ba,bab =b,and a -a2 b is nilpotent.The element b above is unique if it exists and is denoted as aD .The equivalent conditions of the Drazin inverse involving idempotents in R are established.As applications, some formulae for the Drazin inverse of the difference and the product of idempotents in a ring are given.Hence,a number of results of bounded linear operators in Banach spaces are extended to the ring case. 展开更多
关键词 idempotent Drazin inverse spectral idempotent
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Using involutory and idempotent matrices over finite fields to construct cartesian authentication codes 被引量:4
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作者 游宏 郑宝东 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 1999年第3期18-21,共4页
Two constructions of Cartesian authentication codes form involutory and idempotent matrices over finitefields are presented and their size Parameters are computed. Moreover, assume that the encoding rules are chosen a... Two constructions of Cartesian authentication codes form involutory and idempotent matrices over finitefields are presented and their size Parameters are computed. Moreover, assume that the encoding rules are chosen ac-cording to a uniform Probablity distribution, the PI and Ps which dend the largest Probablities of a successful impersonation attack and a successful substitution attack respectively of these codes are also computed. Finially, it is Provedthat thase two Cartesian authentication codes are isomorphic. 展开更多
关键词 AUTHENTICATION involutory idempotent
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ON THE INVERTIBILITY OF HILBERT SPACE IDEMPOTENTS 被引量:2
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作者 邓春源 《Acta Mathematica Scientia》 SCIE CSCD 2014年第2期523-536,共14页
This note is to present some results on the group invertibility of linear combina- tions of idempotents when the difference of two idempotents is group invertible.
关键词 Group inverse linear combination of idempotents
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Generalized n-idempotents and Hyper-generalized n-idempotents 被引量:2
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作者 邓春源 李启慧 杜鸿科 《Northeastern Mathematical Journal》 CSCD 2006年第4期387-394,共8页
For an integer n ≥2, we say that an operator A is an n-idempotent if A^n = A; A is a generalized n-idempotent if A^n = A^*; A is a hyper-generalized n. idempotent if A^n = A^+. The set of all n-idempotents, all gen... For an integer n ≥2, we say that an operator A is an n-idempotent if A^n = A; A is a generalized n-idempotent if A^n = A^*; A is a hyper-generalized n. idempotent if A^n = A^+. The set of all n-idempotents, all generalized n-idempotents and all hyper-generalized n-idempotents are denoted by In(H), gIn(H) and HgIn(H), respectively. In this note, we obtain a chain of proper inclusions gIn(H) belong to HgIn(H) belong to In+2(H). 展开更多
关键词 idempotent generalized inverse normal operator
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Using Normal Form of Idempotent Matrices over Finite Local Ring Z/p^kZ to Construct Cartesian Authentication Codes 被引量:1
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作者 赵辉芳 南基洙 《Northeastern Mathematical Journal》 CSCD 2007年第2期123-131,共9页
In this paper, we determine the normal forms of idempotent matrices for similarity over finite local rings Z/p^kZ, from which we construct a Cartesian authentication code and compute its size parameters and the probab... In this paper, we determine the normal forms of idempotent matrices for similarity over finite local rings Z/p^kZ, from which we construct a Cartesian authentication code and compute its size parameters and the probabilities of successful impersonation and substitution attack under the hypothesis that the cecoding rules are chosen according to a uniform probability distribution. 展开更多
关键词 idempotent matrix finite local ring Cartesian authentication code
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A CLASS OF NATURALLY ORDERED ABUNDANT SEMIGROUPS WITH A GREATESTIDEMPOTENT
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作者 曾祥金 景奉杰 《Acta Mathematica Scientia》 SCIE CSCD 1997年第2期198-204,共7页
On the base of the construction of abundant semigroups with a normal medial idempotent [14], in this paper we consider a class of naturally ordered abundant semigroups which satisfies the regularity condition and cont... On the base of the construction of abundant semigroups with a normal medial idempotent [14], in this paper we consider a class of naturally ordered abundant semigroups which satisfies the regularity condition and contains a greatest idempotent. Furthermore, we give a completely description of the overall structure of such ordered semigroups via the algebraic structure of them, which generalizes known result obtained by Blyth and McFadden[3]. 展开更多
关键词 abundant semigroups natural order greatest idempotents
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RIESZ IDEMPOTENT OF (n, k)-QUASI-*-PARANORMAL OPERATORS
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作者 曾清平 钟怀杰 《Acta Mathematica Scientia》 SCIE CSCD 2016年第5期1487-1491,共5页
A bounded linear operator T on a complex Hilbert space H is called(n, k)-quasi-*-paranormal if ║T;(T;x) ║;║ T;x║;≥║ T*(T;x)║ for all x ∈ H,where n, k are nonnegative integers. This class of operators has... A bounded linear operator T on a complex Hilbert space H is called(n, k)-quasi-*-paranormal if ║T;(T;x) ║;║ T;x║;≥║ T*(T;x)║ for all x ∈ H,where n, k are nonnegative integers. This class of operators has many interesting properties and contains the classes of n-*-paranormal operators and quasi-*-paranormal operators. The aim of this note is to show that every Riesz idempotent E;with respect to a non-zero isolated spectral point λ of an(n, k)-quasi-*-paranormal operator T is self-adjoint and satisfies ran E;= ker(T- λ) = ker(T- λ)*. 展开更多
关键词 *-class A operator *-paranormal operator Riesz idempotent
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THE EXISTENCE OF OVERLARGE SETS OF IDEMPOTENT QUASIGROUPS
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作者 常彦勋 雷建国 《Acta Mathematica Scientia》 SCIE CSCD 2004年第2期165-170,共6页
A idempotent quasigroup (Q, o) of order n is equivalent to an n(n-1)×3 partial orthogonal array in which all of rows consist of 3 distinct elements. Let X be a (n+1)-set. Denote by T(n+1) the set of (n+1)n(n-1) o... A idempotent quasigroup (Q, o) of order n is equivalent to an n(n-1)×3 partial orthogonal array in which all of rows consist of 3 distinct elements. Let X be a (n+1)-set. Denote by T(n+1) the set of (n+1)n(n-1) ordered triples of X with the property that the 3 coordinates of each ordered triple are distinct. An overlarge set of idempotent quasigroups of order n is a partition of T(n+1) into n+1 n(n-1)×3 partial orthogonal arrays A_x, x∈X based on X\{x}. This article gives an almost complete solution of overlarge sets of idempotent quasigroups. 展开更多
关键词 Pairwise balanced design conjugate invariant subgroup overlarge set of idempotent quasigroups
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Some results on derivations of MV-algebras 被引量:1
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作者 WANG Jun-tao HE Peng-fei SHE Yan-hong 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2023年第1期126-143,共18页
In this paper, we review some of their related properties of derivations on MValgebras and give some characterizations of additive derivations. Then we prove that the fixed point set of Boolean additive derivations an... In this paper, we review some of their related properties of derivations on MValgebras and give some characterizations of additive derivations. Then we prove that the fixed point set of Boolean additive derivations and that of their adjoint derivations are isomorphic.In particular, we prove that every MV-algebra is isomorphic to the direct product of the fixed point set of Boolean additive derivations and that of their adjoint derivations. Finally we show that every Boolean algebra is isomorphic to the algebra of all Boolean additive(implicative)derivations. These results also give the negative answers to two open problems, which were proposed in [Fuzzy Sets and Systems, 303(2016), 97-113] and [Information Sciences, 178(2008),307-316]. 展开更多
关键词 mv-algebra DERIVATION fixed point set IDEAL Boolean algebra
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Idempotent Elements of the Semigroups BX(D) Defined by Semilattices of the Class ∑3 (X,8) When Z7
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作者 G. Tavdgiridze Ya. Diasamidze O. Givradze 《Applied Mathematics》 2016年第9期953-966,共14页
In this paper, complete semigroup binary relation is defined by semilattices of the class . We give a full description of idempotent elements of given semigroup. For the case where X is a finite set and , we derive fo... In this paper, complete semigroup binary relation is defined by semilattices of the class . We give a full description of idempotent elements of given semigroup. For the case where X is a finite set and , we derive formulas by calculating the numbers of idempotent elements of the respective semigroup. 展开更多
关键词 SEMILATTICE SEMIGROUP Binary Relation idempotent Element
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Idempotent Elements of the Semigroups Bx(D) Defined by Semilattices of the Class ∑3(x,8) When Z7‡Ø
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作者 Giuli Tavdgiridze Yasha Diasamidze Omari Givradze 《Applied Mathematics》 2016年第3期193-218,共26页
In the paper, complete semigroup binary relation is defined by semilattices of the class . We give a full description of idempotent elements of given semigroup. For the case where X is a finite set and , we derive for... In the paper, complete semigroup binary relation is defined by semilattices of the class . We give a full description of idempotent elements of given semigroup. For the case where X is a finite set and , we derive formulas by calculating the numbers of idempotent elements of the respective semigroup. 展开更多
关键词 SEMILATTICE Semigroup Binary Relation idempotent Element
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On Primitive Idempotents of the Strong Endomorphism Monoid of a Graph
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作者 李为民 《Chinese Quarterly Journal of Mathematics》 CSCD 1997年第4期20-26, ,共7页
In this paper, we describe the canonical partial order on the idempotent set of the strong endomorphism monoid of a graph, and using this we further characterize primitive idem potenes from the viewpoint of combinator... In this paper, we describe the canonical partial order on the idempotent set of the strong endomorphism monoid of a graph, and using this we further characterize primitive idem potenes from the viewpoint of combinatorics. The number of them is also given. 展开更多
关键词 strong endomorphism primitive idempotent MONOID GRAPH
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On the Number of Idempotent Partial Contraction Mappings of a Finite Chain
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作者 Oladapo Adekunle Ojo Fatma Salim Ali Al-Kharousi Abdullahi Umar 《Open Journal of Discrete Mathematics》 2021年第3期94-101,共8页
<span style="font-family:Verdana;">Let <img alt="" src="Edit_1798cf4c-b9a5-4ada-b2d4-9fbf535a6d28.png" />be the partial symmetric semigroup on <img alt="" src=&qu... <span style="font-family:Verdana;">Let <img alt="" src="Edit_1798cf4c-b9a5-4ada-b2d4-9fbf535a6d28.png" />be the partial symmetric semigroup on <img alt="" src="Edit_86c31e58-0588-44fc-8ff3-78c73dc14be6.png" />and let <img alt="" src="Edit_09f7ec2a-49d1-463d-952e-93fbe00740cd.png" />and <img alt="" src="Edit_4aca07c1-9a36-44b6-83af-46fdd6278ca4.png" />be its subsemigroups of order-preserving contractions and order-preserving, order-decreasing contractions mappings of <img alt="" src="Edit_72d2bbdf-2b96-4812-a993-f49640bb98c9.png" />, respectively. In this paper we investigate the cardinalities of <img alt="" src="Edit_95038cdc-5496-495f-bfb9-29c817ba2df4.png" />and <img alt="" src="Edit_f8d3d782-ff8c-43b3-84af-d21a3f4291d5.png" />, the set idempotents of <img alt="" src="Edit_ac8237f8-83ec-4767-9029-b546377bf106.png" />and <img alt="" src="Edit_8b1bf8bf-7472-453c-965d-7308da5b4f4c.png" />, respectively. We also investigate the cardinalities of certain equivalences on <img alt="" src="Edit_e5f7aec4-67c1-48ba-8d03-ea6ceb2e7627.png" />and <img alt="" src="Edit_42a31943-fe9d-4ea8-8999-3aadb705fb38.png" />.</span> 展开更多
关键词 HEIGHT Right (Left) Waist and Fix of a Transformation idempotentS
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保持等价关系的变换半群的一些结果
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作者 王守峰 陈辉 《西北师范大学学报(自然科学版)》 2024年第1期5-10,共6页
给出了保持等价关系的变换半群上的格林关系L,R,H和格林*-关系L^(*),R^(*),H^(*)相容的充要条件,刻画了这类半群的左(右,完全)正则性,得到了这类半群的全体幂等元(正则元,富足元)构成子半群的等价描述.
关键词 变换半群 格林*-关系 正则性 富足元 幂等元
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具有中间幂等元的r-宽大半群 被引量:3
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作者 白雪娜 宫春梅 《云南大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第1期1-7,共7页
讨论了r-宽大半群上的中间幂等元及其相关幂等元的性质.借此,证明了具有弱型A可乘中间幂等元u的r-宽大半群是自然序r-宽大半群,其中u是最大幂等元.
关键词 r-宽大半群 中间幂等元 自然序 弱型A半群
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基于大语言模型的教育文本幂等摘要方法
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作者 杨兴睿 马斌 +1 位作者 李森垚 钟忺 《计算机工程》 CAS CSCD 北大核心 2024年第7期32-41,共10页
大语言模型在自然语言处理领域蓬勃发展,但在教育数字化领域应用过程中仍面临一系列重要挑战。针对教育数字化领域垂域数据稀缺、摘要长度不稳定导致信息缺失或冗余的问题,提出一种用于教育领域文本摘要的轻量化幂等模型框架IGLM。该模... 大语言模型在自然语言处理领域蓬勃发展,但在教育数字化领域应用过程中仍面临一系列重要挑战。针对教育数字化领域垂域数据稀缺、摘要长度不稳定导致信息缺失或冗余的问题,提出一种用于教育领域文本摘要的轻量化幂等模型框架IGLM。该模型首先采用多源训练进行自适应扩增以提升数据多样性,然后对下游的文本摘要任务进行多种微调。同时,为降低文本长度的影响,设计幂等摘要生成策略拉近初次摘要与幂等摘要来约束模型,减少语料分布不均导致的偏见,结合量化技术在低资源条件下生成更为精确和流畅的摘要文本。实验以ROUGE分数为评估指标,在公开中文文本摘要数据集LCSTS、EDUCATION、NLPCC上进行验证。实验结果表明,该框架在生成摘要的准确率和流畅性上有明显提升,其中ROUGE-1/2/L相较基线模型在LCSTS数据集上分别提升7.9、7.4、8.7个百分点,在EDUCATION数据集上分别提升12.9、15.4、15.7个百分点,在NLPCC数据集上分别提升12.2、11.7、12.7个百分点,验证了模型有效性。 展开更多
关键词 教育数字化 文本摘要 大语言模型 低资源场景 幂等 扩增
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广义幂等元及其性质
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作者 何东林 《甘肃高师学报》 2024年第5期7-11,共5页
文章给出了n-幂等元的定义,它是幂等元的一个推广,讨论n-幂等元的若干性质,证明了当e是环R的n-幂等元时,e^(n-1)和1-e^(n-1)是环R的幂等元,并且对任意x∈R,t=e+(1-e^(n-1))xe^(n-1)是环R的n-幂等元.给出n-幂等元的一个应用,得出当e∈R... 文章给出了n-幂等元的定义,它是幂等元的一个推广,讨论n-幂等元的若干性质,证明了当e是环R的n-幂等元时,e^(n-1)和1-e^(n-1)是环R的幂等元,并且对任意x∈R,t=e+(1-e^(n-1))xe^(n-1)是环R的n-幂等元.给出n-幂等元的一个应用,得出当e∈R是n-幂等元时,环R有左理想分解RR=Re^(n-1)⊕R(1-e^(n-1))和右理想分解RR=e^(n-1)R⊕(1-e^(n-1))R.最后,研究等式xR=yR成立的充要条件,其中x是环R的n-幂等元且y是环R的m-幂等元. 展开更多
关键词 n-幂等元 子环 幂等元 左理想分解 右理想分解
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半群CSP_(n,k)的秩和k方幂等元秩
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作者 龙如兰 张梁松 罗永贵 《常熟理工学院学报》 2024年第2期114-120,124,共8页
设自然数n≥3,P_(n)和S_(n)是有限链X_(n)上的部分变换半群和对称群.对任意的正整数k满足3≤k≤n,令C_(k)=g_(k)是X_(n)上的k-局部循环群且CSP_(n,k)=C_(k)∪(P_(n)\S_(n)),易证CSP_(n,k),是部分变换半群P_(n)的子半群.通过分析半群CSP_... 设自然数n≥3,P_(n)和S_(n)是有限链X_(n)上的部分变换半群和对称群.对任意的正整数k满足3≤k≤n,令C_(k)=g_(k)是X_(n)上的k-局部循环群且CSP_(n,k)=C_(k)∪(P_(n)\S_(n)),易证CSP_(n,k),是部分变换半群P_(n)的子半群.通过分析半群CSP_(n,k),的格林关系和幂等元,获得了半群CSP_(n,k),的极小生成集和k方幂等元极小生成集,进一步确定了半群CSP_(n,k),的秩和k方幂等元秩. 展开更多
关键词 部分变换半群 k-局部循环群 (k方幂等元)极小生成集 (k方幂等元)秩
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幂等矩阵的等价条件及其推广
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作者 魏平 《大学数学》 2024年第1期108-113,共6页
归纳证明了幂等矩阵的一些等价条件,并对一个幂等矩阵只有充分条件成立的结论给出必要条件不成立的例子,进一步探讨得到幂等矩阵的两个充要条件.
关键词 幂等矩阵 矩阵的秩 矩阵对角化 矩阵分解 秩幂等矩阵
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Morphic-幂等环
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作者 甘海美 郭勇华 《曲阜师范大学学报(自然科学版)》 CAS 2024年第4期59-63,共5页
首先给出了morphic-幂等环的定义,并证明了环的直积是左morphic-幂等的当且仅当它的每个分量都是左morphic-幂等的.其次,给出了形式三角矩阵环是左morphic-幂等环的一个必要条件.最后,研究了左morphic-幂等环的平凡扩张.
关键词 左morphic-幂等环 形式三角矩阵环 平凡扩张
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