CNN超混沌系统伪随机序列发生器设计

基于CNN超混沌系统,设计了一种混沌伪随机序列发生器。通过对细胞神经网络系统的理论分析及仿真实验可知,该系统具有复杂的动力学特性,具有初值敏感性、密钥空间大等特点,非常适合作为伪随机序列发生器。基于该系统的发生器能够产生两种不同的序列,一种为二进制序列,另一种为十进制序列,并且通过该发生器产生的伪随机序列具有良好的性能,如序列值的均匀分布性、尖锐的自相关特性和良好的互相关特性。除此之外,利用NIST标准对序列发生器进行性能检验,检验结果表明该序列满足伪随机序列的要求,具有较高的安全性和保密性,具有较好的应用前景。     

流密码中伪随机序列发生器的构造与应用

伪随机序列的性质和构造是流密码中的研究重点。针对m-序列的线性复杂度较低而存在被破译的可能性,提出了一种改进的非线性伪随机发生器。经统计实验分析,该伪随机序列生成的密钥流具有较高的线性复杂度和良好的密码学特性。     

基于FPGA的扩频通信中伪随机序列跳码技术的实现

本文实现用跳码序列来代替传统的单一静态伪码序列来进行扩频通信。通过改变序列发生器的初始化状态,以及在传输过程中时刻改变序列发生器的反馈方式来产生抗干扰性强、具有高速的跳码伪随机序列。本方法基于FPGA来实现产生以Gold序列为基础的跳码序列,产生的跳码序列可以应用在S-CDMA、OCHM以及跳码/跳频通信系统中,实验结果表明应用此方法产生的跳码序列具有更好的通信性能。     

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.     

由m序列生成非线性序列的C语言实现

对m序列线性移位寄存器的状态图进行状态重组可以得到一类非线性移位寄存器的状态图,从而获得一类非线性伪随机序列。本文首先将生成非线性伪随机序列的条件演绎成严谨的数学语言,然后将移位寄存器的状态表看成二维数组,给出了在C语言环境下生成m序列并进行状态重组生成非线性伪随机序列的编程方法,用这种方法可以生成大量的非线性伪随机序列。     

基于FPGA的高速多模式PN码并行产生算法研究

介绍了一种高速并行多模式伪随机码(Pseudo-random Number,PN)的实现方法,可以有效提高伪随机序列运算速率。与传统的串行伪随机序列发生器结构比,并行伪随机序列运算速度可以提高L倍,其中L为并行路数。首先从理论上分析了基于伪随机序列的并行多模式实现原理。然后以四路并行为例,对伪随机序列运算做了仿真验证。最后在X ilinx的V ir-tex4系列芯片上实现了并行多模式伪随机序列。现场编程门阵列(F ield Programm ab le Gate Array,FPGA)编译以及测试结果表明,该序列发生器仅占用少量的资源。设计方案已经在卫星通信系统中得到应用。     

伪随机序列发生器的研究与实现

研究了伪随机序列的随机特征,推导出M序列具备伪随机序列的特征,给出M序列的反馈逻辑函数,设计了M序列发生器;分析了测试电路产生的n阶伪随机序列的波形图.通过对测试结果的分析、比较发现,关于反馈移位寄存器的阶数与序列长度关系、码元的游程(该序列的伪随机性)等方面的分析是正确的,验证了该设计的可行性.     

二维可控细胞自动机伪随机序列发生方法研究

提出了一种新的细胞自动机———二维可控细胞自动机。根据二维可控细胞自动机的性质,提出了一 种具有梯型结构的二维可控细胞自动机的伪随机序列发生方法。计算机模拟表明,具有梯型结构的二维可控细 胞自动机伪随机序列发生器实现简单,产生的序列具有速度高、统计特性好等优点。新的细胞自动机在对称密 码学中有广泛地应用。     

一种伪随机控制的2 ASK 调制解调电路实现

设计一种以现场可编程门阵列（ FPGA ）作为伪随机序列信号发生器,通过级联方式实现幅度键控（ ASK）数字调制的电路实现方法。首先通过FPGA程序控制产生“0”、“1”等概的周期长度为15的伪随机基带序列,直接数字式频率合成器（ DDS）电路生成模拟载波信号,输入序列与载波信号进行ASK调制,再将ASK已调信号进行包络检波,还原出数字序列。电路测试表明,利用FPGA可以产生正确伪随机序列,ASK调制解调波形与理论分析一致,具有良好的应用价值。     

一种M序列构造和优选实现方法

随着通信技术的发展,伪随机序列在扩展频谱及多址通信系统中的作用越来越重要.M序列作为非线性移位寄存器序列的一种,由于其特殊的优点而被广泛应用.提出了一种构造M序列并从中筛选出符合要求的序列优选集合的方法,并通过Matlab编程构造及筛选实现,对工程应用具有实际的借鉴意义.     

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.     

An Analysis of Catherine＇s Character——Wuthering Heights

Wuthering Heights, Emily Bronte＇s only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.     

Lower Paleozoic oil relationships within Williston Basin, Canada

The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.     

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.     

Design and analysis of generic LBS application developing platform

Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.     

橡胶颗粒沥青混合料低温抗裂性试验研究

以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.     

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-