多标量乘算法的快速实现

标量乘及多标量乘算法是实现椭圆曲线密码系统的关键，如何快速高效实现标量乘及多标量乘算法是研究的重点。将基于滑动窗口的NAF算法引入到interleaving算法中，提出了基于滑动窗口NAF的interleaving算法，该算法在计算速度方面优于基本interleaving算法。     

基于DSP的ECC快速数字签名的实现

标量乘运算是影响椭圆曲线签名算法执行效率的重要因素之一．针对椭圆曲线密码体制的快速标量乘法,提出用NAF和变长滑动窗口相结合的方法大大减少点加运算次数,同时分别用雅可比坐标和稚可比一仿射坐标法避免倍点运算和点加运算中的求逆,提高点加、倍点运算速度,并将其应用到基于TMS320VC5402的椭圆曲线数字签名．结果表明,签名运算速度得到了很大提高．     

NAF算法的改进

椭圆曲线上的点乘运算是影响椭圆曲线加密（ECC）效率的一个关键因素。本文分析了普遍用于点乘算法的非相邻表示型（NAF）算法,对NAF算法和窗口宽度w的NAF算法进行了改进。本算法减少了运算中的移位运算次数,缩短了运算时间。经分析,改进算法的运行效率是原算法效率的 倍,建模仿真也表明改进算法的运行时间要短于原算法的运行时间。     

An Improvement of Fast Scalar Multiplication Algorithm on Elliptic Curves Over GF(2 n)

利用椭圆曲线密码体制上点乘运算改进的m进制方法,对一种标量乘法快速算法作了进一步改进,结果表明改进后的算法减少了椭圆曲线点乘运算的计算量及存储空间,并提高了运算效率.     

GF(2~n)上椭圆曲线标量乘法快速算法的改进

利用椭圆曲线密码体制上点乘运算改进的m进制方法,对一种标量乘法快速算法作了进一步改进,结果表明改进后的算法减少了椭圆曲线点乘运算的计算量及存储空间,并提高了运算效率.     

椭圆曲线密码体制中点乘的快速算法

对已有的计算椭圆曲线密码体制中点乘的常用算法进行性能分析,在此基础上,针对非相邻形式算法(NAF)存在的不足,提出一种改进的基于NAF的窗口算法,并与其它的几种算法进行了比较.结果表明,改进算法减少了点乘运算中点加和倍乘的运算次数,运算效率比一般的二进制算法提高了25%.     

一种椭圆曲线标量乘的DSP并行算法

计算椭圆曲线标量乘是椭圆曲线密码算法的基础, 为了提高运算效率,探讨了椭圆曲线标量乘的基本实现算法,并设计了DSP并行环境,提出了一种并行实现算法.实验表明该并行算法有效地提高了标量乘运算的效率.     

基于NAFw的二进制域乘法算法

椭圆曲线上的乘法运算速度是提高椭圆曲线加密(ECC)性能的一个关键;分析了宽度w的非相邻表示型(NAF)算法和多项式乘法算法,提出了一个基于NAFw的二进制域乘法算法;算法减少了运算中的异或运算次数和预计算个数,缩短了运算时间且节省了存储空间;经建模仿真,结果表明本算法运算效率较comb多项式乘法平均快14.7%左右,预计算只需要计算2w-1-1个,从存储预计算个数和时间消耗综合考虑w=4也是较优的窗口宽度选择。     

自适应的椭圆曲线滑动窗口标量乘法

在公共密钥密码体系中,椭圆曲线加密算法是一种非常流行的方法,影响椭圆曲线算法执行效率的因素有很多,标量乘法就是一个重要因素．文中分析了几种现有的椭圆曲线标量乘法后,提出了一种改进的计算椭圆曲线标量乘法的算法,即自适应的滑动窗口标量乘算法．文中给出了改进算法中几个重要函数的实现方法,分析了改进算法的执行效率,并给出实验结果．     

基域F(2m)上椭圆曲线快速算法的分析与比较

研究了域F（2m）上椭圆曲线算法的快速实现,介绍了标量乘法的四种快速优化算法,并对这四种快速算法的特点进行了详细的分析与比较,分析与比较表明,最高效的快速算法是将NAF与变长滑动窗口算法结合起来。     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that     

On the Thermodynamic Limit for Responses to Static Electromagnetic Fields

For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the     

Call for Papers

<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with     

Journal of Donghua University ( English Edition) Contents of Volume 31

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