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极大等重等距码的结构分析 被引量:9
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作者 杨义先 《电子学报》 EI CAS CSCD 北大核心 1993年第7期97-100,共4页
本文是文献[1]的继续,首次解决了(非线性)极大等重等距码(n,2,m)和(n,4,m)的等价分类问题,从而清晰地揭示了其结构特征。文中还提出了一些有待进一步研究的问题。
关键词 等重码 等距码 纠错码 非线性 置换
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密码体制中的正形置换的构造与记数 被引量:9
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作者 亢保元 《电子与信息学报》 EI CSCD 北大核心 2002年第9期1294-1296,共3页
正形置换在密码体制中有重要应用,该文在前人工作的基础上,利用有限群的理论对正形置换的构造和记数问题进行了讨论,特别在正形置换的记数方面得到了有价值的结果。
关键词 密码 正形置换 构造 记数 有限群 保密通信
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A Method of Estimating Computational Complexity Based on Input Conditions for N-vehicle Problem 被引量:5
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作者 Xi Xia Jin-chuan Cui 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 2010年第1期1-12,共12页
This paper proposes a method of estimating computational complexity of problem through analyzing its input condition for N-vehicle exploration problem. The N-vehicle problem is firstly formulated to determine the opti... This paper proposes a method of estimating computational complexity of problem through analyzing its input condition for N-vehicle exploration problem. The N-vehicle problem is firstly formulated to determine the optimal replacement in the set of permutations of 1 to N. The complexity of the problem is factorial of N (input scale of problem). To balance accuracy and efficiency of general algorithms, this paper mentions a new systematic algorithm design and discusses correspondence between complexity of problem and its input condition, other than just putting forward a uniform approximation algorithm as usual. This is a new technique for analyzing computation of NP problems. The method of corresponding is then presented. We finally carry out a simulation to verify the advantages of the method: 1) to decrease computation in enumeration; 2) to efficiently obtain computational complexity for any N-vehicle case; 3) to guide an algorithm design for any N-vehicle case according to its complexity estimated by the method. 展开更多
关键词 Complexity of computation combinatorial optimization N-vehicle problem permutations inverse order
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A Relationship between the Partial Bell Polynomials and Alternating Run Polynomials
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作者 Yanan Feng Zhe Wang 《Open Journal of Discrete Mathematics》 2023年第2期49-54,共6页
In this note, we first derive an exponential generating function of the alternating run polynomials. We then deduce an explicit formula of the alternating run polynomials in terms of the partial Bell polynomials.
关键词 Alternating Run Polynomials Bell Polynomials permutations
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影响高中生组合推理的因素 被引量:3
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作者 胡海霞 汪晓勤 《数学教育学报》 北大核心 2009年第6期26-29,共4页
排列组合是高中数学课程中比较难教和难学的内容.如何有效地改进该知识点的教学,是摆在中学数学教师面前的一个重要课题.改进排列组合教学的重要途径之一是确定导致学生排列组合学习困难的变量.对学过和未学过排列组合知识的高中生... 排列组合是高中数学课程中比较难教和难学的内容.如何有效地改进该知识点的教学,是摆在中学数学教师面前的一个重要课题.改进排列组合教学的重要途径之一是确定导致学生排列组合学习困难的变量.对学过和未学过排列组合知识的高中生的测试结果表明:教学和组合运算均显著影响了高中生的组合推理,而组合模型、元素性质对学生的组合推理并没有显著影响. 展开更多
关键词 排列 重复排列 组合 组合模型 组合运算 组合推理
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F_2~n上的正形置换 被引量:4
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作者 常祖领 柯品惠 +1 位作者 莫骄 温巧燕 《北京邮电大学学报》 EI CAS CSCD 北大核心 2006年第1期115-118,共4页
讨论了正形置换的构造和性质,并分析了正形置换的幂次是否仍是正形置换.对于线性正形置换,根据矩阵标准型的性质,只要整数i不能被这个正形置换对应矩阵的极小多项式的各个根的阶整除,则这个线性正形置换的i次幂仍是线性正形置换.对于非... 讨论了正形置换的构造和性质,并分析了正形置换的幂次是否仍是正形置换.对于线性正形置换,根据矩阵标准型的性质,只要整数i不能被这个正形置换对应矩阵的极小多项式的各个根的阶整除,则这个线性正形置换的i次幂仍是线性正形置换.对于非线性正形置换,给出了有用的结果. 展开更多
关键词 置换 正形置换 若当标准型
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Watermarking Images in the Frequency Domain by Exploiting Self-Inverting Permutations
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作者 Maria Chroni Angelos Fylakis Stavros D. Nikolopoulos 《Journal of Information Security》 2013年第2期80-91,共12页
In this work we propose efficient codec algorithms for watermarking images that are intended for uploading on the web under intellectual property protection. Headed to this direction, we recently suggested a way in wh... In this work we propose efficient codec algorithms for watermarking images that are intended for uploading on the web under intellectual property protection. Headed to this direction, we recently suggested a way in which an integer number w which being transformed into a self-inverting permutation, can be represented in a two dimensional (2D) object and thus, since images are 2D structures, we have proposed a watermarking algorithm that embeds marks on them using the 2D representation of w in the spatial domain. Based on the idea behind this technique, we now expand the usage of this concept by marking the image in the frequency domain. In particular, we propose a watermarking technique that also uses the 2D representation of self-inverting permutations and utilizes marking at specific areas thanks to partial modifications of the image’s Discrete Fourier Transform (DFT). Those modifications are made on the magnitude of specific frequency bands and they are the least possible additive information ensuring robustness and imperceptiveness. We have experimentally evaluated our algorithms using various images of different characteristics under JPEG compression. The experimental results show an improvement in comparison to the previously obtained results and they also depict the validity of our proposed codec algorithms. 展开更多
关键词 WATERMARKING Techniques Image WATERMARKING Algorithms Self-Inverting permutations 2D REPRESENTATIONS of permutations ENCODING DECODING Frequency Domain Experimental Evaluation
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Constructing parallel long-message signcryption scheme from trapdoor permutation 被引量:1
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作者 HU ZhenYu LIN DongDai +1 位作者 WU WenLing FENG DengGuo 《Science in China(Series F)》 2007年第1期82-98,共17页
A highly practical parallel signcrypUon scheme named PLSC from trapdoor permutations (TDPs for short) was built to perform long messages directly. The new scheme follows the Idea "scramble all, and encrypt small",... A highly practical parallel signcrypUon scheme named PLSC from trapdoor permutations (TDPs for short) was built to perform long messages directly. The new scheme follows the Idea "scramble all, and encrypt small", using some scrambling operation on message m along with the user's Identities, and then passing, In paraliel, small parts of the scrambling result through corresponding TOPs. This design enables the scheme to flexibly perform long messages of arbitrary length while avoid repeatedly invoking TDP operations such as the CBC mode, or verbosely black-box composing symmetric encryption and slgncryption, resulting in noticeable practical sevlngs in both message bandwidth and efficiency. Concretely, the signcryptlon scheme requires exactly one computation of the "receiver's TDP" (for "encryptlon") and one Inverse computation of the "sender's TDP" (for "authentication"), which Is of great practical significance in directly performing long messages, since the major bottleneck for many public encryptlon schemes is the excessive computational overhead of performing TDP operations. Cutting out the verbosely repeated padding, the newly proposed scheme Is more efficient than a black-box hybrid scheme. Most importantly, the proposed scheme has been proven to be tightly semanUcaiiy secure under adaptive chosen clphertext attacks (iND-CCA2) and to provide integrity of clphertext (INT-CTXT) as well as non-repudiation in the random oracle model. All of these security guarantees are provided in the full multi-user, insider-security setting. Moreover, though the scheme is designed to perform long messages, it may also be appropriate for settings where It is Impractical to perform large block of messages (i.e. extremely low memory environments such as smart cards). 展开更多
关键词 authenticated encryption SIGNCRYPTION trapdoor permutations PARALLEL
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POSITIVE MAPS CONSTRUCTED FROM PERMUTATION PAIRS 被引量:1
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作者 Jinchuan HOU Haili ZHAO 《Acta Mathematica Scientia》 SCIE CSCD 2019年第1期148-164,共17页
A property(C) for permutation pairs is introduced. It is shown that if a pair{π_1, π_2} of permutations of(1,2,…,n) has property(C),then the D-type map Φ_(π_1,π_2) on n× n complex matrices constructed from ... A property(C) for permutation pairs is introduced. It is shown that if a pair{π_1, π_2} of permutations of(1,2,…,n) has property(C),then the D-type map Φ_(π_1,π_2) on n× n complex matrices constructed from {π_1,π_2} is positive. A necessary and sufficient condition is obtained for a pair {π_1,π_2} to have property(C),and an easily checked necessary and sufficient condition for the pairs of the form {π~p,π~q} to have property(C) is given, whereπ is the permutation defined by π(i) = i + 1 mod n and 1≤ p < q≤ n. 展开更多
关键词 matrix ALGEBRAS positive linear MAPS permutations quantum information
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广义Bent函数的性质研究 被引量:2
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作者 吴仕文 余昭平 《通信学报》 EI CSCD 北大核心 2000年第5期54-56,共3页
本文在Zqn→Zq 上讨论了广义Bent函数的有关性质 ,给出了一类新的广义Bent函数。
关键词 广义BENT函数 置换 性质
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排列组合应用题的解题原则和策略 被引量:3
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作者 高有才 马玉田 《大庆高等专科学校学报》 2004年第4期5-7,共3页
排列组合问题的内容比较抽象,解题方法比较灵活,很多学生感到难学,尤其在解应用题时不知从 何入手。针对上述情况,本文从排列组合问题的解题原则和解题策略两方面阐述了解排列组合应用题的 方法,并附以相应的例题。
关键词 排列组合应用题 解题原则 排列组合问题 解应用题 解题方法 例题 解题策略 抽象
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关于“TSP”的算法研究 被引量:1
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作者 郑自途 《天津理工学院学报》 2002年第3期50-54,共5页
n阶完全图 (边赋权 )的矩阵每行每列最小元素对应着一个次数为n的置换 ,若从这些最小元素组成的所有圈中每圈至少取出一个元素并令其为∞ ,那么仅包含这些元素的子矩阵可以经过初等变换将这些元素置于主对角线上形成一个新矩阵 ,其每行... n阶完全图 (边赋权 )的矩阵每行每列最小元素对应着一个次数为n的置换 ,若从这些最小元素组成的所有圈中每圈至少取出一个元素并令其为∞ ,那么仅包含这些元素的子矩阵可以经过初等变换将这些元素置于主对角线上形成一个新矩阵 ,其每行每列最小元素又对应一个新的置换 .在满足一定条件时 ,两个置换合成能够得到一个次数为n的循环置换 .运用这种方法 。 展开更多
关键词 算法研究 TSP 最小元素 组合 置换 合成 n阶完全图 H-圈 旅行商问题 矩阵变换
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超几何概率教学探讨 被引量:3
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作者 赵永祥 李丽 《重庆三峡学院学报》 2014年第3期32-34,共3页
超几何分布是产品计数抽样检验、可靠性计算中经常遇到的一类重要的数理统计模型.在求解实际问题时,首先要根据超几何分布问题的特点判断所求问题是否为超几何概率问题,然后才能确定是否用超几何概率公式.同时,探讨了学生在求超几何概... 超几何分布是产品计数抽样检验、可靠性计算中经常遇到的一类重要的数理统计模型.在求解实际问题时,首先要根据超几何分布问题的特点判断所求问题是否为超几何概率问题,然后才能确定是否用超几何概率公式.同时,探讨了学生在求超几何概率问题时的一个误解. 展开更多
关键词 随机变量 超几何分布 排列
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Generalized Eulerian Numbers
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作者 Alfred Wünsche 《Advances in Pure Mathematics》 2018年第3期335-361,共27页
We generalize the Eulerian numbers ?to sets of numbers Eμ(k,l), (μ=0,1,2,···) where the Eulerian numbers appear as the special case μ=1. This can be used for the evaluation of generalizations Eμ(k,Z... We generalize the Eulerian numbers ?to sets of numbers Eμ(k,l), (μ=0,1,2,···) where the Eulerian numbers appear as the special case μ=1. This can be used for the evaluation of generalizations Eμ(k,Z) of the Geometric series G0(k;Z)=G1(0;Z) by splitting an essential part (1-Z)-(μK+1) where the numbers Eμ(k,l) are then the coefficients of the remainder polynomial. This can be extended for non-integer parameter k to the approximative evaluation of generalized Geometric series. The recurrence relations and for the Generalized Eulerian numbers E1(k,l) are derived. The Eulerian numbers are related to the Stirling numbers of second kind S(k,l) and we give proofs for the explicit relations of Eulerian to Stirling numbers of second kind in both directions. We discuss some ordering relations for differentiation and multiplication operators which play a role in our derivations and collect this in Appendices. 展开更多
关键词 EULERIAN NUMBERS EULERIAN Polynomials STIRLING NUMBERS permutations Binomials HYPERGEOMETRIC Functions Geometric Series Vandermonde’s Convolution Identity Recurrence Relations Operator ORDERINGS
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MicroPath-A pathway-based pipeline for the comparison of multiple gene expression profiles to identify common biological signatures
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作者 Mohsin Khan Chandrasekhar Babu Gorle +2 位作者 Ping Wang Xiao-Hui Liu Su-Ling Li 《Journal of Biomedical Science and Engineering》 2009年第2期106-116,共11页
High throughput gene expression analysis is swiftly becoming the focal point for deciphering molecular mechanisms underlying various dif-ferent biological questions. Testament to this is the fact that vast volumes of ... High throughput gene expression analysis is swiftly becoming the focal point for deciphering molecular mechanisms underlying various dif-ferent biological questions. Testament to this is the fact that vast volumes of expression profiles are being generated rapidly by scientists worldwide and subsequently stored in publicly available data repositories such as ArrayEx-press and the Gene Expression Omnibus (GEO). Such wealth of biological data has motivated biologists to compare expression profiles gen-erated from biologically-related microarray ex-periments in order to unravel biological mecha-nisms underlying various states of diseases. However, without the availability of appropriate software and tools, they are compelled to use manual or labour-intensive methods of com-parisons. A scrutiny of current literature makes it apparent that there is a soaring need for such bioinformatics tools that cater for the multiple analyses of expression profiles. In order to contribute towards this need, we have developed an efficient software pipeline for the analysis of multiple gene expression data-sets, called Micropath, which implements three principal functions;1) it searches for common genes amongst n number of datasets using a number crunching method of comparison as well as applying the principle of permutations and combinations in the form of a search strat-egy, 2) it extracts gene expression patterns both graphically and statistically, and 3) it streams co-expressed genes to all molecular pathways belonging to KEGG in a live fashion. We sub-jected MicroPath to several expression datasets generated from our tolerance-related in-house microarray experiments as well as published data and identified a set of 31 candidate genes that were found to be co-expressed across all interesting datasets. Pathway analysis revealed their putative roles in regulating immune toler-ance. MicroPath is freely available to download from: www.1066technologies.co.uk/micropath. 展开更多
关键词 CO-EXPRESSION ANALYSIS Microarray permutations and COMBINATIONS MULTIPLE Gene Expression ANALYSIS
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Solving the Class Equation x<sup>d</sup>= β in an Alternating Group for Each β ∈ C<sup>α</sup>∩ H<sub>n</sub><sup>c</sup>and n >1
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作者 Shuker Mahmood Andrew Rajah 《Advances in Linear Algebra & Matrix Theory》 2012年第2期13-19,共7页
The main purpose of this paper is to solve the class equation in an alternating group, (i.e. find the solutions set ) and find the number of these solutions where ranges over the conjugacy class in and d is a positive... The main purpose of this paper is to solve the class equation in an alternating group, (i.e. find the solutions set ) and find the number of these solutions where ranges over the conjugacy class in and d is a positive integer. In this paper we solve the class equation in where , for all . is the complement set of where { of , with all parts of are different and odd}. is conjugacy class of and form class depends on the cycle type of its elements If and , then splits into the two classes of . 展开更多
关键词 Alternating Groups permutations Conjugate Classes Cycle Type FROBENIUS Equation
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Single-Cycle Bit Permutations with MOMR Execution
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作者 李佩露 杨骁 史志杰 《Journal of Computer Science & Technology》 SCIE EI CSCD 2005年第5期577-585,共9页
Secure computing paradigms impose new architectural challenges for general-purpose processors. Cryptographic processing is needed for secure communications, storage, and computations. We identify two categories of ope... Secure computing paradigms impose new architectural challenges for general-purpose processors. Cryptographic processing is needed for secure communications, storage, and computations. We identify two categories of operations in symmetric-key and public-key cryptographic algorithms that are not common in previous general-purpose workloads: advanced bit operations within a word and multi-word operations. We define MOMR (Multiple Operands Multiple Results) execution or datarich execution as a unified solution to both challenges. It allows arbitrary n-bit permutations to be achieved in one or two cycles, rather than O(n) cycles as in existing RISC processors. It also enables significant acceleration of multiword multiplications needed by public-key ciphers. We propose two implementations of MOMR: one employs only hardware changes while the other uses Instruction Set Architecture (ISA) support. We show that MOMR execution leverages available resources in typical multi-issue processors with minimal additional cost. Multi-issue processors enhanced with MOMR units provide additional speedup over standard multi-issue processors with the same datapath. MOMR is a general architectural solution for word-oriented processor architectures to incorporate datarich operations. 展开更多
关键词 PERMUTATION bit permutations CRYPTOGRAPHY cryptographic acceleration security multi-word operation datarich execution MOMR instruction set architecture ISA PROCESSOR high performance secure computing
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Double Derangement Permutations
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作者 Pooya Daneshmand Kamyar Mirzavaziri Madjid Mirzavaziri 《Open Journal of Discrete Mathematics》 2016年第2期99-104,共6页
Let n be a positive integer. A permutation a of the symmetric group  of permutations of  is called a derangement if   for each . Suppose that x and y are two arbitrary permutations of . We say that... Let n be a positive integer. A permutation a of the symmetric group  of permutations of  is called a derangement if   for each . Suppose that x and y are two arbitrary permutations of . We say that a permutation a is a double derangement with respect to x and y if  and  for each . In this paper, we give an explicit formula for , the number of double derangements with respect to x and y. Let  and let  and  be two subsets of  with  and . Suppose that  denotes the number of derangements x such that . As the main result, we show that if  and z is a permutation such that  for  and  for , then  where . 展开更多
关键词 Symmetric Group of permutations Derangement Double Derangement
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On the Pólya Enumeration Theorem
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作者 L. G. FEL 《Intelligent Information Management》 2009年第3期172-173,共2页
Simple formulas for the number of different cyclic and dihedral necklaces containing nj beads of the j-th color, and , are derived, using the Pólya enumeration theorem.
关键词 permutations and CYCLIC INVARIANCE cycle index Pólya ENUMERATION THEOREM
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ENUMERATION OF LATIN ARRAYS (Ⅰ)——CASE n≤3
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作者 陶仁骥 陈世华 《Science China Mathematics》 SCIE 1990年第12期1430-1438,共9页
This paper introduces the concept of Latin arrays, discusses the general property on their enumeration, and gives formulae of numbers for (2,k)- and (3,k)-Latin arrays and for their isotopy classes.
关键词 LATIN array LATIN SQUARE family of permutations ISOTOPY classes.
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