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基于模运算的数字水印算法 被引量:34
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作者 夏光升 陈明奇 +1 位作者 杨义先 胡正名 《计算机学报》 EI CSCD 北大核心 2000年第11期1146-1150,共5页
提出了一种基于模运算的数字水印算法 .该算法具有很好的性能 :(1)水印隐藏的效果好 ,凭借人类的视觉系统无法看出与原图像的差别 ;(2 )可以有效的抵抗 JPEG等压缩编码的破坏 ;(3)可以依靠部分图像检测水印 ,在图像受到损坏的情况下 ,... 提出了一种基于模运算的数字水印算法 .该算法具有很好的性能 :(1)水印隐藏的效果好 ,凭借人类的视觉系统无法看出与原图像的差别 ;(2 )可以有效的抵抗 JPEG等压缩编码的破坏 ;(3)可以依靠部分图像检测水印 ,在图像受到损坏的情况下 ,仍可以检测到水印信息 ;(4 )检测水印时受到口令的限制 ,不知道口令的人无法正确恢复水印 ;(5 )检测水印时不需要原始图像 . 展开更多
关键词 数字水印 模运算 算法 著作权 图像编码
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一种基于模运算的数字水印隐藏算法 被引量:20
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作者 宋琪 朱光喜 +1 位作者 容太平 罗航建 《电子学报》 EI CAS CSCD 北大核心 2002年第6期890-892,共3页
数字水印技术是进行数字产品版权保护的一种手段 .本文提出了一种基于模运算的数字水印隐藏方法 ,该方法具有以下性能 :①水印的隐藏效果较好 ;②在水印的嵌入和提取过程中需个人的密钥 ,因此不知该密钥的用户无法正确恢复水印 ;③在计... 数字水印技术是进行数字产品版权保护的一种手段 .本文提出了一种基于模运算的数字水印隐藏方法 ,该方法具有以下性能 :①水印的隐藏效果较好 ;②在水印的嵌入和提取过程中需个人的密钥 ,因此不知该密钥的用户无法正确恢复水印 ;③在计算嵌入水印的位置时 ,采用了具有不可逆性质的方法 ,因而非法用户无法获得水印的嵌入位置 ;④水印的提取无需原始图像 ;⑤可以抵抗LSB进攻、BIT COMPLEMENT[4 ] 进攻和剪切进攻 . 展开更多
关键词 模运算 数字水印 隐藏算法 版权保护 数据隐藏 数据 保护 网络化
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关于丢番图方程x ̄3±125=Dy ̄2 被引量:11
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作者 李复中 《东北师大学报(自然科学版)》 CAS CSCD 1996年第3期15-16,共2页
给出了方程x ̄3±125=Dy ̄2的全部非平凡整数解.其中D>0,无平方因子,且不能被3或6l+1型的素数整除.
关键词 丢番图方程 整数解 非平凡解
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软件流水中隐藏存储延迟的方法 被引量:6
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作者 刘利 李文龙 +2 位作者 陈彧 李胜梅 汤志忠 《软件学报》 EI CSCD 北大核心 2005年第10期1833-1841,共9页
软件流水是一种重要的指令调度技术,它通过同时执行来自不同循环体的指令来加快循环的执行速度.随着处理机运行速度的逐渐提高,存储访问延迟成为性能提高的瓶颈.为了减轻存储系统影响,软件流水结合了一些存储优化技术,通过隐藏存储延迟... 软件流水是一种重要的指令调度技术,它通过同时执行来自不同循环体的指令来加快循环的执行速度.随着处理机运行速度的逐渐提高,存储访问延迟成为性能提高的瓶颈.为了减轻存储系统影响,软件流水结合了一些存储优化技术,通过隐藏存储延迟来提高性能.提出了一种延迟可预测的模调度算法(foresightedlatencymoduloscheduling,简称FLMS),它根据循环的特点来确定load指令延迟.实验结果表明,FLMS算法减少了阻塞时间,提高了程序性能. 展开更多
关键词 软件流水 模调度涪储延迟 FLMS(foresighted LATENCY modulo scheduling)
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Algorithm for Visualization of Zero Divisor Graphs of the Ring ℤn Using MAPLE Coding
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作者 Nasir Ali 《Open Journal of Discrete Mathematics》 2024年第1期1-8,共8页
This research investigates the comparative efficacy of generating zero divisor graphs (ZDGs) of the ring of integers ℤ<sub>n</sub> modulo n using MAPLE algorithm. Zero divisor graphs, pivotal in the study ... This research investigates the comparative efficacy of generating zero divisor graphs (ZDGs) of the ring of integers ℤ<sub>n</sub> modulo n using MAPLE algorithm. Zero divisor graphs, pivotal in the study of ring theory, depict relationships between elements of a ring that multiply to zero. The paper explores the development and implementation of algorithms in MAPLE for constructing these ZDGs. The comparative study aims to discern the strengths, limitations, and computational efficiency of different MAPLE algorithms for creating zero divisor graphs offering insights for mathematicians, researchers, and computational enthusiasts involved in ring theory and mathematical computations. 展开更多
关键词 Zero Divisor Graph Ring Theory Maple Algorithm n modulo n Graph Theory Mathematical Computing
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New Results on One Modulo N-Difference Mean Graphs
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作者 Pon Jeyanthi Meganathan Selvi Damodaran Ramya 《Open Journal of Discrete Mathematics》 2023年第4期100-112,共13页
A graph G is said to be one modulo N-difference mean graph if there is an injective function f from the vertex set of G to the set , where N is the natural number and q is the number of edges of G and f induces a bije... A graph G is said to be one modulo N-difference mean graph if there is an injective function f from the vertex set of G to the set , where N is the natural number and q is the number of edges of G and f induces a bijection  from the edge set of G to given by and the function f is called a one modulo N-difference mean labeling of G. In this paper, we show that the graphs such as arbitrary union of paths, , ladder, slanting ladder, diamond snake, quadrilateral snake, alternately quadrilateral snake, , , , , friendship graph and admit one modulo N-difference mean labeling. 展开更多
关键词 Skolem Difference Mean Labeling One modulo N-Graceful Labeling One modulo N-Difference Mean Labeling and One modulo N-Difference Mean Graph
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关于一类丢番图方程x^3±(3~k)~3=Dy^2 被引量:7
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作者 李复中 《东北师大学报(自然科学版)》 CAS CSCD 1997年第3期31-33,共3页
给出了一类不定方程x3±(3k)3=Dy2的全部非平凡整数解.其中D>0,无平方因子,且不能被6l+1型的素数整除,k≥1.
关键词 丢番图方程 整数解 非平凡解
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关于一类丢番图方程x^3±(5~k)~3=Dy^2 被引量:7
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作者 李复中 《东北师大学报(自然科学版)》 CAS CSCD 1998年第2期16-19,共4页
给出了一类不定方程x3±(5k)3=Dy2的全部非平凡整数解.其中D>0,无平方因子,且不能被3或6l+1型的素数整除.
关键词 丢番图方程 非平凡整数解 同余
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基于提升方案小波和水印加密的盲水印算法 被引量:6
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作者 陈东方 张有清 《计算机应用》 CSCD 北大核心 2008年第3期615-619,共5页
提出一种利用提升方案小波对载体图像进行多个金字塔分解的方法,并结合新的水印置乱加密方法进行数字水印。嵌入水印时,先对水印信息进行扩频,再利用基于模运算的方法嵌入水印。实验结果表明,该算法增强了水印信息的安全性,同时具有很... 提出一种利用提升方案小波对载体图像进行多个金字塔分解的方法,并结合新的水印置乱加密方法进行数字水印。嵌入水印时,先对水印信息进行扩频,再利用基于模运算的方法嵌入水印。实验结果表明,该算法增强了水印信息的安全性,同时具有很好的透明性和鲁棒性。 展开更多
关键词 提升方案小波 金字塔分解 加密 扩频 模运算
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Comparison of PM_(10) concentrations and metal content in three different sites of the Venice Lagoon: An analysis of possible aerosol sources 被引量:4
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作者 Daniele Contini Franco Belosi +3 位作者 Andrea Gambaro Daniela Cesari Angela Maria Stortini Maria Chiara Bove 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2012年第11期1954-1965,共12页
The Venice Lagoon is exposed to atmospheric pollutants from industrial activities, thermoelectric power plants, petrochemical plants, incinerator, domestic heating, ship traffic, glass factories and vehicular emission... The Venice Lagoon is exposed to atmospheric pollutants from industrial activities, thermoelectric power plants, petrochemical plants, incinerator, domestic heating, ship traffic, glass factories and vehicular emissions on the mainland. In 2005, construction began on the mobile dams (MOSE), one dam for each channel connecting the lagoon to the Adriatic Sea as a barrier against high tide. These construction works could represent an additional source of pollutants. PM10 samples were taken on random days between 2007 and 2010 at three different sites: Punta Sabbioni, Chioggia and Malamocco, located near the respective dam construction worksites. Chemical analyses of V, Cr, Fe, Co, Ni, Cu, Zn, As, Mo, Cd, Sb, T1 and Pb in PM10 samples were performed by Inductively coupled plasma- quadrupole mass spectrometry (ICP-QMS) and results were used to identify the main aerosol sources. The correlation of measured data with meteorology, and source apportionment, failed to highlight a contribution specifically associated to the emissions of the MOSE construction works. The comparison of the measurements at the three sites showed a substantial homogeneity of metal concentrations in the area. Source apportionment with principal component analysis (PCA) and positive matrix factorization (PMF) showed that a four principal factors model could describe the sources of metals in PM10. Three of them were assigned to specific sources in the area and one was characterised as a source of mixed origin (anthropogenic and crustal). A specific anthropogenic source of PM10 rich in Ni and Cr, active at the Chioggia site, was also identified. 展开更多
关键词 modulo Sperimentale Elettromeccanico metals Venice Lagoon PM10 principal component analysis positive matrixfactorization
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Minimal Context-Switching Data Race Detection with Dataflow Tracking
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作者 郑龙 李洋 +4 位作者 辛杰 刘海峰 郑然 廖小飞 金海 《Journal of Computer Science & Technology》 SCIE EI CSCD 2024年第1期211-226,共16页
Data race is one of the most important concurrent anomalies in multi-threaded programs.Emerging con-straint-based techniques are leveraged into race detection,which is able to find all the races that can be found by a... Data race is one of the most important concurrent anomalies in multi-threaded programs.Emerging con-straint-based techniques are leveraged into race detection,which is able to find all the races that can be found by any oth-er sound race detector.However,this constraint-based approach has serious limitations on helping programmers analyze and understand data races.First,it may report a large number of false positives due to the unrecognized dataflow propa-gation of the program.Second,it recommends a wide range of thread context switches to schedule the reported race(in-cluding the false one)whenever this race is exposed during the constraint-solving process.This ad hoc recommendation imposes too many context switches,which complicates the data race analysis.To address these two limitations in the state-of-the-art constraint-based race detection,this paper proposes DFTracker,an improved constraint-based race detec-tor to recommend each data race with minimal thread context switches.Specifically,we reduce the false positives by ana-lyzing and tracking the dataflow in the program.By this means,DFTracker thus reduces the unnecessary analysis of false race schedules.We further propose a novel algorithm to recommend an effective race schedule with minimal thread con-text switches for each data race.Our experimental results on the real applications demonstrate that 1)without removing any true data race,DFTracker effectively prunes false positives by 68%in comparison with the state-of-the-art constraint-based race detector;2)DFTracker recommends as low as 2.6-8.3(4.7 on average)thread context switches per data race in the real world,which is 81.6%fewer context switches per data race than the state-of-the-art constraint based race detec-tor.Therefore,DFTracker can be used as an effective tool to understand the data race for programmers. 展开更多
关键词 data race satisfiability modulo theory multi-threaded program dynamic detection
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反射地震记录的多尺度边缘检测 被引量:5
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作者 钟森 《石油地球物理勘探》 EI CSCD 北大核心 1998年第1期61-65,共5页
多尺度边缘检测等价于寻找图像的小波变换模局部极值。在尺度空间,图像的小波变换模局部极值能在刻画图像不规则结构的局部特征的同时,给出它们的局部奇性点的分布。本文借助这种思路,利用小波变换模的局部极值,检测了二维反射地震... 多尺度边缘检测等价于寻找图像的小波变换模局部极值。在尺度空间,图像的小波变换模局部极值能在刻画图像不规则结构的局部特征的同时,给出它们的局部奇性点的分布。本文借助这种思路,利用小波变换模的局部极值,检测了二维反射地震记录同相轴位置和断点特征位置,即通过沿小波变换模的尺度伸展方向,估计出局部Lipschitz指数和光滑因子,并自动追踪同相轴和识别断点。 展开更多
关键词 小波变换 尺度空间 边缘检测 地震勘探 地震记录
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一种基于DWT域的数字水印方案 被引量:3
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作者 冯象初 张玉双 王卫卫 《计算机科学》 CSCD 北大核心 2002年第7期75-76,共2页
数字媒体(数字图像、数字视频、数字音频等)的版权保护已成为一个迫切需要解决的问题.传统的加密系统在数据传输中虽有保护作用,但数据一旦被接受并解密,其保护作用也随之消失.作为数字媒体版权保护的有效手段,数字水印技术近年来引起... 数字媒体(数字图像、数字视频、数字音频等)的版权保护已成为一个迫切需要解决的问题.传统的加密系统在数据传输中虽有保护作用,但数据一旦被接受并解密,其保护作用也随之消失.作为数字媒体版权保护的有效手段,数字水印技术近年来引起了人们的重视,图像隐形水印是其中最主要的研究方向,它通过在原始图像中嵌入秘密信息-水印来证实图像的所有权归属或保证数据的完整性. 展开更多
关键词 数字图像 随机序列 图像处理 DWT域 数字水印 版权保护 数字媒体
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MAXIMAL PERIOD POLYNOMIALS OVER Z/(p^d)
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作者 黄民强 《Science China Mathematics》 SCIE 1992年第3期270-275,共6页
In tLis paper, we obtain a criterion (basically an algebraic discriminant) for f(x) to havethe maximal modulo p^d period. The principal part θ of the discriminant is based on thecoefficients of f(x) mod p and can be ... In tLis paper, we obtain a criterion (basically an algebraic discriminant) for f(x) to havethe maximal modulo p^d period. The principal part θ of the discriminant is based on thecoefficients of f(x) mod p and can be computed by a recursive method. In particular, thevalues of θ for p=2, 3, 5 and 7 are derived. 展开更多
关键词 POLYNOMIAL MAXIMAL PERIOD modulo p^d criterion.
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Catalan方程x^n+1=y^2的正整数解 被引量:4
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作者 管训贵 《北京教育学院学报(自然科学版)》 2010年第1期1-3,9,共4页
研究了一类不定方程求正整数解的问题.借助数论中的一些简单结果,推导并证明了Catalan方程xn+1=y2的正整数解的一般公式.Catalan方程xn+1=y2的一切正整数解可表示为(x,y,n)=(k2-1,k,1)或(2,3,3),这里k为大于1的正整数.
关键词 Catalan方程 正整数解 同余 整除
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Maximal and Minimal Congruences on Some Semigroups 被引量:1
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作者 Jintana SANWONG Boorapa SINGHA R.P.SULLIVAN 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2009年第3期455-466,共12页
In 2006, Sanwong and Sullivan described the maximal congruences on the semigroup N consisting of all non-negative integers under standard multiplication, and on the semigroup T(X) consisting of all total transformat... In 2006, Sanwong and Sullivan described the maximal congruences on the semigroup N consisting of all non-negative integers under standard multiplication, and on the semigroup T(X) consisting of all total transformations of an infinite set X under composition. Here, we determine all maximal congruences on the semigroup Zn under multiplication modulo n. And, when Y lohtain in X, we do the same for the semigroup T(X, Y) consisting of all elements of T(X) whose range is contained in Y. We also characterise the minimal congruences on T(X. Y). 展开更多
关键词 integers modulo n transformation semigroups maximal congruences minimal congruences
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Evaluate All the Order of Every Element in the Higher Order of Group for Addition and Multiplication Composition
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作者 Md. Abdul Mannan Nazmun Nahar +3 位作者 Halima Akter Momtaz Begum Md. Amanat Ullah Shabnam Mustari 《International Journal of Modern Nonlinear Theory and Application》 2022年第2期11-30,共20页
This paper aims at treating a study on the order of every element for addition and multiplication composition in the higher order of groups for different algebraic structures as groups;order of a group and order of el... This paper aims at treating a study on the order of every element for addition and multiplication composition in the higher order of groups for different algebraic structures as groups;order of a group and order of element of a group in real numbers. Here we discuss the higher order of groups in different types of order which will give us practical knowledge to see the applications of the addition and multiplication composition. If G is a finite group, n is a positive integer and a &isins;G, then the order of the products na. When G is a finite group, every element must have finite order. However, the converse is false: there are infinite groups where each element has finite order. For example, in the group of all roots of unity in C<sup>×</sup> each element has finite order. Finally, we find out the order of every element of a group in different types of higher order of group. 展开更多
关键词 Order of Element of a Group Addition Composition Multiplication Composition modulo
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Pseudo-Randomness of Certain Sequences of k Symbols with Length pq 被引量:1
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作者 陈智雄 杜小妮 吴晨煌 《Journal of Computer Science & Technology》 SCIE EI CSCD 2011年第2期276-282,共7页
The theory of finite pseudo-random binary sequences was built by C. Mauduit and A. Sarkozy and later extended to sequences of k symbols (or k-ary sequences). Certain constructions of pseudo-random sequences of k sym... The theory of finite pseudo-random binary sequences was built by C. Mauduit and A. Sarkozy and later extended to sequences of k symbols (or k-ary sequences). Certain constructions of pseudo-random sequences of k symbols were presented over finite fields in the literature. In this paper, two families of sequences of k symbols are constructed by using the integers modulo pq for distinct odd primes p and q. The upper bounds on the well-distribution measure and the correlation measure of the families sequences are presented in terms of certain character sums over modulo pq residue class rings. And low bounds on the linear complexity profile are also estimated. 展开更多
关键词 stream ciphers pseudo-random sequences well-distribution measure correlation measure discrete logarithm modulo pq residue class rings character sums
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改进的RSA算法在数字签名中的应用 被引量:3
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作者 肖振久 胡驰 陈虹 《计算机工程与应用》 CSCD 2014年第17期106-109,共4页
针对传统RSA密码算法运算效率较低的问题,在标准RSA密码算法的自身结构和具体运算操作两方面做出了相应的改进,提出了一种新的RSA密码优化算法,并将该算法运用到数字签名技术中。然后通过仿真实验,将其与传统RSA算法以及基于乘同余对称... 针对传统RSA密码算法运算效率较低的问题,在标准RSA密码算法的自身结构和具体运算操作两方面做出了相应的改进,提出了一种新的RSA密码优化算法,并将该算法运用到数字签名技术中。然后通过仿真实验,将其与传统RSA算法以及基于乘同余对称特性的SMM算法和指数2k进制化相结合的组合优化算法相比较,实验结果表明新的RSA密码优化算法在提升运算速度方面达到了较高的水平。 展开更多
关键词 RSA算法 数字签名 乘同余对称 模重复平方 SYMMETRY of modulo Multiplication(SMM)
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基于小波的彩色图像公开水印技术 被引量:1
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作者 张军 彭宏 王能超 《华中科技大学学报(自然科学版)》 EI CAS CSCD 北大核心 2003年第6期86-88,共3页
提出了一种新的彩色图像公开水印技术 .首先计算彩色图像的红色与绿色分量的加权平均图 ,然后分别对加权图和蓝色分量图作小波分解 ,最后通过对这两者的粗尺度子图之差进行模运算将图案水印嵌入到蓝色分量图的低频带中 (粗尺度子图 ) .... 提出了一种新的彩色图像公开水印技术 .首先计算彩色图像的红色与绿色分量的加权平均图 ,然后分别对加权图和蓝色分量图作小波分解 ,最后通过对这两者的粗尺度子图之差进行模运算将图案水印嵌入到蓝色分量图的低频带中 (粗尺度子图 ) .实验结果表明 ,该方法具有很好的不可感知性以及对通常图像处理的稳健性 。 展开更多
关键词 彩色图像 公开水印技术 小波变换 模运算
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