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Analysis and Modeling of k-regular and k-connected Protection Structure in Ultra-High Capacity Optical Networks
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作者 LI Xin HUANG Shanguo +3 位作者 ZHANG Jie ZHAO Yongli GU Wanyi WANG Yang 《China Communications》 SCIE CSCD 2015年第3期106-119,共14页
This paper proposes k-regular and k-connected(k&k) structure against multifaults in ultra-high capacity optical networks.Theoretical results show that pre-configured k&k structure can reach the lower bound on ... This paper proposes k-regular and k-connected(k&k) structure against multifaults in ultra-high capacity optical networks.Theoretical results show that pre-configured k&k structure can reach the lower bound on logical redundancy.The switching time of k&k protection structure is as quickly as ringbased protection in SDH network.It is the optimal protection structure in ultra-high capacity optical networks against multi-faults.We develop the linear programming model for k&k structure and propose a construction method for k&k structure design.Simulations are conducted for spare spectrum resources effi ciency of the pre-confi gured k&k structure under multi-faults on representative COST239 and NSFnet topologies.Numerical results show that the spare spectrum resources efficiency of k&k structure can reach the lower bound on logical redundancy in static networks.And it can largely improve spare spectrum resources effi ciency compared with p-cycles based protection structure without reducing protection effi ciency under dynamic traffi cs. 展开更多
关键词 multi-faults k-regular and k-connected structure ultra-high capacity optical networks
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几种数据库加密方法的研究与比较 被引量:18
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作者 赵晓峰 叶震 《计算机技术与发展》 2007年第2期219-222,共4页
随着数据库技术在日常经济生活中应用的不断增加,数据库安全日益成为人们关注的热点。而目前数据库的安全性主要通过访问控制来保障,但是当访问控制被攻破时整个数据库的安全体系也随之瓦解。目前解决此问题的主要方法是采用数据库加密... 随着数据库技术在日常经济生活中应用的不断增加,数据库安全日益成为人们关注的热点。而目前数据库的安全性主要通过访问控制来保障,但是当访问控制被攻破时整个数据库的安全体系也随之瓦解。目前解决此问题的主要方法是采用数据库加密。文中对目前主要的几种数据库加密方法进行了探讨和研究,并指出了数据库加密的发展方向。 展开更多
关键词 数据库加密 秘密同态 子密钥 密钥管理 密文索引
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低对比度手指静脉图像的分割 被引量:2
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作者 刘建科 李洋 《电子技术应用》 北大核心 2012年第12期123-125,共3页
为了克服目前分割算法中低对比度手指静脉图像分割不精确的问题,采用局部动态阈值算法,依据静脉图像中灰度值在空间信息的相关性,设计了新的变权重判定函数,解决分割后产生的伪静脉问题。同时针对一般细化算法在静脉交叉点产生的冗余问... 为了克服目前分割算法中低对比度手指静脉图像分割不精确的问题,采用局部动态阈值算法,依据静脉图像中灰度值在空间信息的相关性,设计了新的变权重判定函数,解决分割后产生的伪静脉问题。同时针对一般细化算法在静脉交叉点产生的冗余问题,提出了新的判断准则,有效地解决了像素冗余问题。实验表明,这些方法能有效地分割低对比度手指静脉图像。 展开更多
关键词 手指静脉 图像分割 同态滤波 局部动态阈值 变权重
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关于拟主k-投射半模的进一步结果(英文) 被引量:1
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作者 王秀丽 周茂袁 +1 位作者 陈志寅 王洪艳 《黑龙江大学自然科学学报》 CAS 北大核心 2012年第3期332-334,338,共4页
在k-投射半模和拟主模的理论基础之上,引进拟主k-投射半模的概念,得到关于拟主k-投射半模的几个性质,这是环中拟主模和半环中k-投射半模性质的推广。证明:如果P是一个正则半模,则它是拟主k-投射半模当且仅当它是投射半模。给出在完全可... 在k-投射半模和拟主模的理论基础之上,引进拟主k-投射半模的概念,得到关于拟主k-投射半模的几个性质,这是环中拟主模和半环中k-投射半模性质的推广。证明:如果P是一个正则半模,则它是拟主k-投射半模当且仅当它是投射半模。给出在完全可吸收可消去半环上与拟主k-投射半模等价的两个条件。 展开更多
关键词 可吸收半模 k-正则同态 拟主k-投射半模 自由半模 真正合列
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广义环
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作者 吕效国 《连云港师范高等专科学校学报》 2006年第3期70-73,共4页
将环、子环(理想)、环的同态(构)、消去律、零因子等定义加以推广,得到了广义环、子广义环(理想)、广义环的同态(构)、广义消去律、因子的定义;并将环的性质、同态基本定理推广到广义环上,得到了广义环的性质、广义环的同态基本定理。
关键词 广义环 子广义环 理想 ε因子 同态
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Quasi-principally k-projective Semimodules 被引量:4
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作者 WANG Xiu-li ZHOU Mao-yuan CHEN Zhi-yin 《Chinese Quarterly Journal of Mathematics》 CSCD 2011年第2期213-216,共4页
In this paper,we principally introduce the concept of quasiprincipally k-projective semimodules,on the basis of the theories of k-projective semimodules and quasi-principally modules,we get some good properties of qua... In this paper,we principally introduce the concept of quasiprincipally k-projective semimodules,on the basis of the theories of k-projective semimodules and quasi-principally modules,we get some good properties of quasi-principally k-projective semimodules,therefore generalize some properties of quasi-principally modules of ring and k-projective semimodules of semiring to quasi-principally k-projective semimodules of semiring. 展开更多
关键词 subtractive semimodules k-regular homomorphism quasi-principally k-projective semimodules proper exact sequence
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Some ResuIts on the Principal Eigenvector 被引量:1
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作者 WU Chun-jie 《Chinese Quarterly Journal of Mathematics》 2020年第4期401-409,共9页
For a simple connected graph G, let A(G) and Q(G) be the adjacency matrix and signless Laplacian matrix, respectively of G. The principal eigenvector of A(G)(resp.Q(G)) is the unit positive eigenvector corresponding t... For a simple connected graph G, let A(G) and Q(G) be the adjacency matrix and signless Laplacian matrix, respectively of G. The principal eigenvector of A(G)(resp.Q(G)) is the unit positive eigenvector corresponding to the largest eigenvalue of A(G)(resp. Q(G)). In this paper, an upper bound and lower bound for the sum of the squares of the entries of the principal eigenvector of Q(G) corresponding to the vertices of an independent set are obtained. 展开更多
关键词 Signless Laplacian Principal eigenvector Independent set k-regular Semiregular
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A Laurent Expansion and Residue Theorems of k-Regular Functions in Clifford Analysis 被引量:2
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作者 KU Min DU Jinyuan 《Wuhan University Journal of Natural Sciences》 CAS 2009年第2期97-102,共6页
In this context, we mainly study the behavior in the neighborhood of finite singular points for k-regular functions in R1^n with values in R0、n. We get a Laurent expansion of them in an open set, prove its uniqueness... In this context, we mainly study the behavior in the neighborhood of finite singular points for k-regular functions in R1^n with values in R0、n. We get a Laurent expansion of them in an open set, prove its uniqueness, give the definitions of k-poles, isolated and essential singular points and removable singularity, discuss some properties, and further obtain the residue theorems. 展开更多
关键词 Clifford algebra k-regular functions Laurent expansion residue theorems SINGULARITY
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余Frame范畴中的等化子和余等化子结构
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作者 王昭海 《模糊系统与数学》 北大核心 2017年第3期16-21,共6页
本文对余Frame范畴(以余Frame为对象,以余Frame同态为态射)中的等化子和余等化子的结构进行了研究。首先,利用子余Frame和嵌入映射构造了两个态射(具有相同论域和相同余论域)的等化子;其次,利用商余Frame和典型映射构造了两个态射(具有... 本文对余Frame范畴(以余Frame为对象,以余Frame同态为态射)中的等化子和余等化子的结构进行了研究。首先,利用子余Frame和嵌入映射构造了两个态射(具有相同论域和相同余论域)的等化子;其次,利用商余Frame和典型映射构造了两个态射(具有相同论域和相同余论域)的余等化子。本文的结果是对余Frame研究工作的补充和完善。 展开更多
关键词 格论 余Frame 余Frame同态 范畴 等化子 余等化子
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On Radon-Penrose transformation and k-Cauchy-Fueter operator 被引量:3
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作者 KANG QianQian WANG Wei 《Science China Mathematics》 SCIE 2012年第9期1921-1936,共16页
It is known that there is a 1-1 correspondence between the first cohomology of the sheaf O(-k-2) over the projective space and the solutions to the k-Cauchy-Fueter equations on the quaternionic space Hn.We find an exp... It is known that there is a 1-1 correspondence between the first cohomology of the sheaf O(-k-2) over the projective space and the solutions to the k-Cauchy-Fueter equations on the quaternionic space Hn.We find an explicit Radon-Penrose type integral formula to realize this correspondence:given a -closed(0,1)form f with coefficients in the(-k-2)th power of the hyperplane section bundle H-k-2,there is an integral representation Pf such that ι*(Pf) is a solution to the k-Cauchy-Fueter equations,where ι is an embedding of the quaternionic space Hn into C4n. 展开更多
关键词 the k-Cauchy-Fueter operator Radon-Penrose integral formula k-regular functions hyperplanesection bundle
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