VB6.O内部随机数发生器性能检验

针对Visual Basic 6.0内部随机数发生器,按无初始化、序列初始化和变量初始化等方法产生随机数序列,并对序列的均匀性和独立性进行实验.统计检验表明:该发生器性能优良,无初始化和序列初始化性能相近,其均匀性被拒绝的概率约10%,独立性被拒绝的概率约30%.如果产生每个随机数时都以当前时钟对发生器进行初始化,所得序列的均匀性略有改进,但独立性不能通过检验.     

基于Weierstrass函数的随机数发生器

研究了Weierstrass函数∑∞n=0ancos(bnπx)中a,b,x的取值对序列{xn}的随机性的影响;证明了b>1时能够产生具有不可预测性的优良随机序列{xn}.在此基础上设计了一个用于数据加密的随机数发生器.和其他的随机数发生器相比,在保持优良的随机性的前提下,该随机数发生器具有序列不可预测、较大的密钥空间、占用较小的存储空间、算法简单、实现方便等优点.在一定程度上加强了随机数发生器的安全性,符合一个较好的随机数发生器的要求.     

基于伪随机码生成器的数字产品加密研究

阐述了随机序列在数字产品产权保护措施中的作用,并对随机序列生成器底层逻辑进行了研究;对线性同余发生器存在的缺陷进行了改进,设计了一种新的随机序列发生器,对改进前后发生器进行参数检验、均匀性检验等随机性进行测试,结果表明,改进后的随机序列发生器有较好的随机性和独立性.     

一类基于动态S盒的混沌伪随机序列发生器

为提高伪随机序列的动力学性质,利用有限群上的随机行走理论,提出了用动态S盒对基于混沌轨道编码模型的伪随机序列发生器产生的伪随机序列进行变换的方法,从而构造出一种新型混沌伪随机序列发生器——基于动态S盒的混沌伪随机序列发生器.这种发生器不仅保持了混沌伪随机序列的均匀性和独立性,而且增强了伪随机序列动力学性质的复杂性,克服了已有混沌伪随机序列的动力学性质比较简单的缺点.     

VB6．0内部随机数发生器性能检验

针对Visual Basic 6．0内部随机数发生器，按无初始化、序列初始化和变量初始化等方法产生随机数序列，并对序列的均匀性和独立性进行实验．统计检验表明：该发生器性能优良，无初始化和序列初始化性能相近，其均匀性被拒绝的概率约l0％，独立性被拒绝的概率约30％．如果产生每个随机数时都以当前时钟对发生器进行初始化，所得序列的均匀性略有改进，但独立性不能通过检验．     

基于直方图均化法的改进Logistic映射伪随机数发生器设计及性能研究

Logistic映射伪随机数发生器(LM-PRNG)可用于生成均匀分布的伪随机数,但直接生成随机数的数据分布均匀性不佳.为此,文中根据LM-PRNG直接生成随机数数据分布的特性,设计了一种基于直方图优化法的改进Logistic伪随机数发生器(ILM-PRNG),并利用参数检验、均匀性检验及独立性检验分析了LM-PRNG和ILM-PRNG的性能.3种数据规模下的测试结果表明:在显著水平α=0.05下,LM-PRNG生成伪随机数序列的一阶矩在数据规模N=10~3和N=10~4时可以通过检验,在N=10~5时通过检验的比例为60%,其二阶矩、方差和均匀性在本次实验中均未通过检验,通过独立性检验的样本数占本次研究样本数的93.3%;ILM-PRNG生成的均匀分布伪随机数均通过参数检验、均匀性检验和独立性检验,其参数性与均匀性均随着生成数据规模的扩大而不断提高,独立性与数据规模的关系不大;ILM-PRNG可以克服LM-PRNG的不足,生成更良好的均匀分布伪随机数,是一种性能良好的新型伪随机数发生器.     

一种LT码编码生成矩阵的伪随机产生方案

常用的LT码编码生成矩阵的传输方案是在每个编码数据包的头部额外增加一个开销,用于放置该数据包对应的编码生成矢量.该方案会产生较大的开销,造成传输效率降低.给出了一种编码生成矩阵在编码器和译码器间伪随机同步产生的方案.采用该方案时,只要编码器和译码器伪随机数发生器的算法相同,种子也相同,就能产生一样的均匀伪随机数序列,将其进行转化后就能得到相同的编码生成矩阵.种子数据量小,且只需要在伪随机数发生器初始化时编码器和译码器间交换一次即可.实验结果显示,生成的伪随机度值符合指定的度分布函数,数据包的伪随机选择也符合泊松分布.相比较传统方案,该方案避免了编码生成矩阵的直接传输,减少了传输开销,提高了传输效率.     

IFS分形图像的组合随机数算法

设计了性能优异的组合随机数序列发生器,通过偏差算子的作用得到取值范围可调的随机数序列,对仿射变换参数系统进行随机调整,控制迭代函数系统（IFS）分形图像的形态变化.以自然景物的树木生长为研究实例,应用计算机图形技术随机生成形态变化多端的树木.实验结果表明,该方法能较好地模拟自然界的一些景象.     

改进线性同余法随机数发生器

在粒子输运Monte Carlo程序中广泛采用线性同余法随机数发生器。为了改善该发生器产生的随机数序列的统计品质,该文基于洗牌法思想设计了一种新的随机数发生器。在新算法中,以原线性同余法随机数发生器的中间整型变量为基础,通过位操作来构造实现洗牌效果所需的随机整型变量。由于位操作的计算量较少,使得新算法在计算量上不会有明显的增加。而统计检验的结果表明,该方法对随机数序列统计品质的改善是显著的。同时,该文还阐述了新算法在并行环境中的应用。     

基于振荡采样的真随机数发生器IP设计

为了得到真正硬件产生的随机数序列,采用振荡电路作为物理源,设计了混洗电路和扰频电路来改善输出序列的均衡性和数据冗余,它具有真随机数发生器的不可预测性高、随机性好的优点.理论分析表明,采用该方法可使获得的随机数序列达到完全的均衡分布,计算验证和检测结果也证实了其输出序列的随机性要好于未经处理的输出序列.最后给出了一种使用FIFO实现的随机数发生器模块跨时钟域总线接口.该设计能够较好地与系统其他模块相集成.     

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     

An affordable accurate evaluation of the binding conformations predicted by molecular docking studies in bio-system

Franck-Condon factors bridge the gap between theoretical modeling and experimental observations for molecular electronic spectroscopy and electron transfer.Under the displaced harmonic oscillator approximation,multidimensional Franck-Condon factors are decomposed into a product of many one-dimensional(1D)Franck-Condon(FC)factors,and each 1D-FC factor is associated with one Huang-Rhys factor that determines the leading contribution of     

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