随机性测试的淘汰能力和相关性

随机数序列在密码学中有着至关重要的作用,实际应用中考虑到序列生成的时间和复杂度,通常使用的是存在某些缺陷的伪随机数序列,它们给密码系统带来了一定的风险性。因此,需要使用随机性测试来对生成的序列进行检验,NIST在一个测试包中收录了16个随机性测试,这是目前较为常用的测试包之一,它们相互间的关系及其优劣性一直是一个值得探讨的问题。     

Standard Reference Material (SRM 1990) For Single Crystal Diffractometer Alignment

An international project was successfully completed which involved two major undertakings: (1) a round-robin to demonstrate the viability of the selected standard and (2) the certification of the lattice parameters of the SRM 1990, a Standard Reference Material^® for single crystal diffractometer alignment. This SRM is a set of ≈3500 units of Cr-doped Al₂O₃, or ruby spheres [(0.420.011 mole fraction % Cr (expanded uncertainty)]. The round-robin consisted of determination of lattice parameters of a pair of crystals: the ruby sphere as a standard, and a zeolite reference to serve as an unknown. Fifty pairs of crystals were dispatched from Hauptman-Woodward Medical Research Institute to volunteers in x-ray laboratories world-wide. A total of 45 sets of data was received from 32 laboratories. The mean unit cell parameters of the ruby spheres was found to be a=4.7608 ű0.0062 Å, and c=12.9979 ű0.020 Å (95 % intervals of the laboratory means). The source of errors of outlier data was identified. The SRM project involved the certification of lattice parameters using four well-aligned single crystal diffractometers at (Bell Laboratories) Lucent Technologies and at NRC of Canada (39 ruby spheres), the quantification of the Cr content using a combined microprobe and SEM/EDS technique, and the evaluation of the mosaicity of the ruby spheres using a double-crystal spectrometry method. A confirmation of the lattice parameters was also conducted using a Guinier-Hägg camera. Systematic corrections of thermal expansion and refraction corrections were applied. These rubies_– are rhombohedral, with space group R3¯c. The certified mean unit cell parameters are a=4.76080±0.00029 Å, and c=12.99568 ű0.00087 Å (expanded uncertainty). These certified lattice parameters fall well within the results of those obtained from the international round-robin study. The Guinier-Hägg transmission measurements on five samples of powdered rubies (a=4.7610 ű0.0013 Å, and c = 12.9954 ű0.0034 Å) agreed well with the values obtained from the single crystal spheres.     

NIST ATM/HFC网络仿真器的使用

NIST ATM／HFC网络仿真是美国国家标准与技术协会（NIST）为研究人员和网络规划者不用建立昂贵的真实网络就可以对ATM／HFC网络进行分析而设计的仿真软件。此仿真是一种使用图形用户接口（GUI）给使用者提供交互式的建模环境的工具，运用此工具可以建立不同的网络拓扑结构，控制网络组件的参数，观测网络的行为，记录下仿真运行的数据。本文对其具体使用给予一定的叙述，以期让大家更好地使用此软件。     

改进型NIST测试对ZUC算法随机序列的可视化检测

保障网络空间安全通常采用序列密码算法对信息进行加密,利用统计模式检验一个序列密码算法生成序列的质量好坏可以采用NIST检验标准中的检测方法对其输出序列进行检测,然后通过所获得的统计数据结果进行判断。NIST提供的检测方法仅对单个序列进行测量具有密钥流利用率不高,结果不够直观等缺点。本文描述对NIST的检测方法进行改进后形成系统检测的新方法。首先对密钥流采用多分段计算的方法,增加了密钥流的利用率,使得一个长密钥流形成多个测量度量使测量结果系统化,将所获得的数据进行分组统计,通过公式将系统测量结果转化为二维图像,使得结果直观可视化。将其应用在对ZUC算法的检测上,更好地展现出ZUC算法的统计特性。经过检测后观察到ZUC算法产生的序列密码具有良好的随机性,并且当密钥流越长,图像上的特征点聚集程度越高。     

A numerical simulation tool for nanoscale ion‐sensitive field‐effect transistor

In this work, a self‐contained numerical simulation tool for nanoscale Ion‐Sensitive Field‐Effect Transistor (ISFET) is developed. The tool is based on merging nanoscale ballistic MOSFET analytical equations with the Gouy–Chapman–Stern model equations of ISFET to form a system of nonlinear equations that can be solved iteratively to yield ISFET output current. The numerical solution is accomplished using Newton–Raphson method with efficient trust‐region‐dogleg algorithm using MATLAB software coding. The tool is used to optimize the sensitivity and linearity of nanoscale ISFETs, and to study their dependence on reference voltage, drain current level, and gate‐insulator thickness. Moreover, a comparison between three types of insulators, SiO₂, Si₃N₄, and Al₂O₃, has been made. The tool is given the name: NIST (Nanoscale ISFET Simulation Tool). It can be used as a guide for design and optimization of nanoscale ISFETs and can be applied for both single‐gate and double‐gate structures. Copyright © 2016 John Wiley & Sons, Ltd.     

基于人体指纹特征的随机序列发生器

利用人体指纹特征本身内在的唯一性、不可预测性和外部随机噪声(光照、损伤等)给出了产生随机序列的一类新方法--基于人体指纹特征的随机序列发生器,实现了人体生物特征与密码的结合.使用自相关函数方法和BDS统计检验方法验证了该随机序列优良的线性不相关性和非线性不相关性,得到了完全不可预测的非周期随机序列.通过美国国家标准技术研究院(NIST)推荐的标准随机统计测验FIPS140-1 Tests和NIST Special Publication 800-22 Tests对该随机序列进行了检验.检验结果表明基于人体指纹特征的随机序列发生器是满足密码安全的随机序列发生器,并且实现简单、方便.     

浅析云计算及其在电信运营商中的应用

首先介绍了云计算技术的概念、发展情况,定位电信运营商在云计算产业链中的地位,分析了云计算给运营商带来的机遇和挑战,重点阐述了云计算在电信企业中的应用。     

Efficient neural chaotic generator for image encryption

In this paper, we propose a new implementation of chaotic generator using artificial neural network. Neural network can act as an efficient source of perturbation in the chaotic generator which increases the cycleʼs length, and thus avoid the dynamical degradation due to the used finite dimensional space. On the other hand, the use of neural network enlarges the key space of the chaotic generator in an enormous way. The efficiency of the proposed neural chaotic generator is illustrated using some dynamical and NIST statistical tests. We also propose in this paper, a new image encryption method based on chaotic sequence, and the obtained results emphasize the efficiency of our technique.     

两种安全风险评估方法NIST与OCTAVE的比较研究

本文以NIST信息安全风险评估的九个步骤为参照框架,详细比较研究了NIST与OCTAVE安全风险评估过程的异同。     

Neutron radiography measurements of in-situ PEMFC liquid water saturation in 2D & 3D morphology gas diffusion layers

This work uses neutron radiography to examine the through-plane liquid water distribution of an operating polymer electrolyte membrane fuel cell (PEMFC) with a Sigracet SGL 25BC, a 235 μm thick, 2D straight fiber Gas Diffusion Layer (GDL). This work is performed for interdigitated flow fields at several cross flow rates, and a parallel flow field for comparison. The effect on pressure drop, effective permeability and liquid water saturation is determined. These results are compared to the previously studied Sigracet SGL 10BC, a 420 μm thick, 3D “spaghetti” fiber GDL, for comparable cross flow rates. The SGL 25BC has a higher permeability than the SGL 10BC. The 25BC has a relatively constant saturation within the GDL, from 8% to 10%, which is higher than the 10BC saturation level, between 4 and 8%. This may indicate that 2D GDLs may be better suited to low pumping power situations, while 3D GDLs may be better suited to low liquid water situations.