New designing of cryptosystems based on quadratic fields

This paper proposes a method to construct new kind of non-maximal imaginary quadratic order （NIQO＊） by combining the technique of Diophantine equation and the characters of non-maximal imaginary quadratic order. It is proved that in the class group of this new kind of NIQO＊, it is very easy to design provable secure cryptosystems based on quadratic field （QF）. With the purpose to prove that this new kind of QF-based cryptosystems are easy to implement, two concrete schemes are presented, i.e., a Schnorr-like signature and an EIGamel-like encryption, by using the proposed NIQO＊. In the random oracle model, it is proved that： （1） under the assumption that the discrete logarithm problem over class groups （CL-DLP） of this new kind of NIQO＊ is intractable, the proposed signature scheme is secure against adaptive chosen-message attacks, i.e., achieving UF-CMA security; （2） under the assumption that the decisional Diffie-Hellman problem over class groups （CL-DDH） of this new kind of NIQO＊ is intractable, the enhanced encryption in this paper is secure against adaptive chosen-ciphertext attacks, i.e., reaching IND-CCA2 security.     

Cryptography on elliptic curves over <Emphasis Type="Italic">p</Emphasis>-adic number fields

In this paper we introduce a cryptosystem based on the quotient groups of the group of rational points of an elliptic curve defined over p-adic number field. Some additional parameters are taken in this system, which have an advantage in performing point multiplication while keeping the security of ECC over finite fields. We give a method to select generators of the cryptographic groups, and give a way to represent the elements of the quotient groups with finitely bounded storage by establishing a bijection between these elements and their approximate coordinates. The addition formula under this representation is also presented.     

Cryptanalysis of Achterbahn-Version 1 and -Version 2

Achterbahn is one of the candidate stream ciphers submitted to the eSTREAM, which is the ECRYPT Stream Cipher Project. The cipher Achterbahn uses a new structure which is based on several nonlinear feedback shift registers （NLFSR） and a nonlinear combining output Boolean function. This paper proposes distinguishing attacks on Achterbahn-Version 1 and -Version 2 on the reduced mode and the full mode. These distinguishing attacks are based on linear approximations of the output functions. On the basis of these linear approximations and the periods of the registers, parity checks with noticeable biases are found. Then distinguishing attacks can be achieved through these biased parity checks. As to Achterbahn-Version 1, three cases that the output function has three possibilities are analyzed. Achterbahn-Version 2, the modification version of Achterbahn-Version 1, is designed to avert attacks based on approximations of the output Boolean function. Our attack with even much lower complexities on Achterbahn-Version 2 shows that Achterbahn-Version 2 cannot prevent attacks based on linear approximations.     

A conjecture on the norm of Lyapunov mapping

A conjecture that the norm of Lyapunov mapping LA equals to its restriction to the symmetric set, S, i.e., ｜｜LA｜｜ =｜｜LA｜s｜｜ was proposed in [1]. In this paper, a method for numerical testing is provided first. Then, some recent progress on this conjecture is presented.     

Progress and Prospect of Some Fundamental Research on Information Security in China

With the development of network and information technologies, information security is more and more widely researched in China. To know where the work is and where it goes, we focus on comprehensively surveying the twenty years of important fundamental research by Chinese scholars, and giving, from our point of view, the significance as well as the outlook of future work. Some of the reviewed work, including the researches on fundamental theory of cryptography, cryptographic algorithm, security protocol, security infrastructure and information hiding, greatly advances the related sub-fields, and is highly recognized in and outside of China. Nevertheless, the overall work, we think, is still facing the problems of unbalanced development of sub-areas, limited scope of research, lack of systematic work and application, etc., leaving much room for improvement in the near future.     

A new adaptive mutative scale chaos optimization algorithm and its application

Based on results of chaos characteristics comparing one-dimensional iterative chaotic self-map x = sin（2/x） with infinite collapses within the finite region[-1, 1] to some representative iterative chaotic maps with finite collapses （e.g., Logistic map, Tent map, and Chebyshev map）, a new adaptive mutative scale chaos optimization algorithm （AMSCOA） is proposed by using the chaos model x = sin（2/x）. In the optimization algorithm, in order to ensure its advantage of speed convergence and high precision in the seeking optimization process, some measures are taken： 1） the searching space of optimized variables is reduced continuously due to adaptive mutative scale method and the searching precision is enhanced accordingly; 2） the most circle time is regarded as its control guideline. The calculation examples about three testing functions reveal that the adaptive mutative scale chaos optimization algorithm has both high searching speed and precision.     

Memorizable interactive proof and zero-knowledge proof systems

Interactive proof and zero-knowledge proof systems are two important concepts in cryptography and complexity theory. In the past two decades, a great number of interactive proof and zero-knowledge proof protocols have been designed and applied in practice. In this paper, a simple memorizable zero-knowledge protocol is proposed for graph non-isomorphism problem, based on the memorizable interactive proof system,which is extended from the original definition of interactive proof and is more applicable in reality.     

State feedback stabilization for high-order stochastic nonlinear systems with zero dynamics

In this paper, for a class of high-order stochastic nonlinear systems with zero dynamics which are neither necessarily feedback linearizable nor affine in the control input, the problem of state feedback stabilization is investigated for the first time. Under some weaker assumptions, a smooth state feedback controller is designed, which ensures that the closed-loop system has an almost surely unique solution on [0,∞）, the equilibrium at the origin of the closed-loop system is globally asymptotically stable in probability, and all the states can be regulated to the origin almost surely. A simulation example demonstrates the control scheme.     

Method of Direct Texture Synthesis on Arbitrary Surfaces

A direct texture synthesis method on arbitrary surfaces is proposed in this paper. The idea is to recursively map triangles on surface to texture space until the surface is completely mapped. First, the surface is simplified and a tangential vector field is created over the simplified mesh. Then, mapping process searches for the most optimal texture coordinates in texture sample for each triangle, and the textures of neighboring triangles are blended on the mesh. All synthesized texture triangles are compressed to an atlas. Finally, the simplified mesh is subdivided to approach the initial surface. The algorithm has several advantages over former methods: it synthesizes texture on surface without local parameterization; it does not need partitioning surface to patches; and it does not need a particular texture sample. The results demonstrate that the new algorithm is applicable to a wide variety of texture samples and any triangulated surfaces.     

A learning particle swarm optimization algorithm for odor source localization

This paper is concerned with the problem of odor source localization using multi-robot system. A learning particle swarm optimization algorithm, which can coordinate a multi-robot system to locate the odor source, is proposed. First, in order to develop the proposed algorithm, a source probability map for a robot is built and updated by using concentration magnitude information, wind information, and swarm information. Based on the source probability map, the new position of the robot can be generated. Second, a distributed coordination architecture, by which the proposed algorithm can run on the multi-robot system, is designed. Specifically, the proposed algorithm is used on the group level to generate a new position for the robot. A consensus algorithm is then adopted on the robot level in order to control the robot to move from the current position to the new position. Finally, the effectiveness of the proposed algorithm is illustrated for the odor source localization problem.     

Residual-based specification of a hidden random field included in a hierarchical spatial model

A method for specifying a hidden random field (HRF) included in a hierarchical spatial model is proposed. In hierarchical models of interest the first stage describes, conditional on a realization of the HRF, a response variable which is observable on a continuous spatial domain; the second stage models the HRF which reflects unobserved spatial heterogeneity. The question which is investigated is how can the HRF be modeled, i.e. specified. The method developed to address this question is based on residuals obtained when the base model, i.e. the hierarchical model in which the HRF is assumed constant, is fitted to data. It is shown that the residuals are linked with the HRF, and the link is used to specify the HRF. The method is applied to simulated data in order to assess its performance, and then to real data on radionuclide concentrations on Rongelap Island.     

领域本体中概念间语义相关度的概率估计

根据贝叶斯定理提出一种衡量领域本体中概念间语义相关度的概率模型。该模型定义在不同语义关系之上,基于极大似然估计法利用语义距离来对语义关系进行参数估计。并在此基础给出一种计算任意两个概念之间语义相关度的方法。公开数据集上的实验结果表明该方法估计出的概念语义相关度具有相当的有效性,应用在语义查询扩展中可明显提高检索效果。     

科学计算软件快速开发技术的研究

讨论了C＋＋语言与Matlab语言结合快速开发科学计算软件的优越性和可行性，Visual C 调用Matlab函数的几种方法，其中着重探讨Matlab函数在Visual C 中的编译技术以及如何在Visual C 中调用Matlab Shared M-DII，开发Windows平台独立可执行文件的技术。作为例程给出了Visual C 中开发小波分析软件的步骤和要点，给出了源代码，程序在Win2000系统下成功编译，并能独立运行在Win9x和Win2000操作系统上。     

基于WebService的高校应用集成

目前高校中都存在业务系统异构难于集成的问题.根据这个问题,提出了基于WebService的高校应用集成的解决方案.该方案主要是把高校中现存的业务系统通过重新改造成WebService,从而利用WebService良好的低耦合性和标准性,实现应用集成.在WebService的基础上,给出了高校应用集成的SOA架构;给出了该架构下每个模块的技术实现,其中遗留业务系统的改造是最困难的部分;最后在WSAD上实现了一个业务模块的改造.在技术上实现了基于WebService的高校应用集成,并成功实现了一个业务模块,从而证明了基于WebService的高校应用集成的可行性,并给出了下一步的改进方向.     

可识别声源深度的三维声聚焦波束形成方法

当前平面传声器阵列结合波束形成方法进行声源识别定位时,存在不能确定声源相对全息测量阵列距离的问题,提出了可识别声源深度的三维声聚焦波束形成方法。基于球面波声场模型和波束形成方法,在不同深度的平面上进行声聚焦,首先根据聚焦面上波束形成功率的最大点位置沿聚焦深度方向（即z方向）的轨迹变化判断声源在z方向的位置,再进一步确定声源在x和y方向的位置。为验证方法的有效性,在点声源构成的声场中进行了仿真验证,并且在全消声室内进行了单声源及多声源识别定位的实验验证。仿真结果和实验结果一致表明：该方法能够实现基于平面阵列的三维空间中声源的识别定位。     

计算机网络安全与防火墙技术

防火墙技术的核心思想是在不安全的网际网环境中构造一个相对安全的子网环境。本文介绍了防火墙技术的基本概念和系统结构,讨论了实现防火墙的两种主要技术手段：一种是基于分组过滤技术（Packetfiltering）,它的代表是在筛选路由器上实现的防火墙功能;一种是基于代理技术（Proxy）,它的代表是在应用层网关上实现的防火墙功能。     

基于对抗图卷积网络的链接预测模型

大部分的链接预测模型在挖掘节点相似性时过于依赖已知的链接信息,但在真实世界中,已知的观测链接数量通常较少.因此,为了提高模型的鲁棒性,需要提高解耦模型对链接信息的依赖并挖掘节点的潜在特征.文中考虑节点特征和链接之间的潜在关系,提出基于对抗图卷积网络的链接预测模型.首先利用节点间的相似性度量填充邻接矩阵中部分未知链接,缓解链接稀疏对图卷积模型的影响.再利用对抗网络深度挖掘节点特征和链接之间的潜在联系,降低模型对链接的依赖.在真实数据集上的实验表明,文中模型在链接预测问题上具有较好的表现力,在链接稀疏的情况下性能依旧较稳定,同时适用于大规模数据集.     

网络管理中一种互认证密码协议的安全性分析

基于串空间模型的极小元和理想理论,对网络管理中的一种互认证密码协议进行保密性和认证性分析,通过分析发现该协议存在冗余部分,并提出相应的改进方案;同时在协议的认证性设计方面,指出基于非对称密码系统和对称密码系统的认证协议的区别。     

基于CUDA的并行K-近邻连接算法实现

针对大规模空间数据的K-近邻连接查询问题,设计了一种CUDA编程模型下K-近邻连接算法的并行优化方法。将K-近邻连接算法的并行过程分两个阶段:1)对参与查询的数据集P和Q分别建立R-Tree索引;2)基于R-Tree索引进行KNNJ查询。首先根据结点所在位置划分最小外包框,在CUDA下基于递归网格排序算法创建R-Tree索引。然后在CUDA下基于R-Tree索引进行KNNJ查询,其中涉及并行求距离和并行距离排序两个阶段:求距离阶段利用每一个线程计算任意两点之间的距离,点与点之间距离的求取无依赖并行;排序阶段将快速排序基于CUDA以实现并行化。实验结果表明,随着样本量的不断增大,基于R-Tree索引的并行K-近邻连接算法的优势更加明显,具有高效性和可扩展性。     

基于Eisenstein环上圆锥曲线的数字签名

为了使曲线上的密码体制更加安全有效,引进Eisenstein环 ,介绍剩余类环 上的圆锥曲线 ,其中, 为 上满足 的2个不同的不可分数 的乘积。给出基于 的盲签名方案在圆锥曲线 上的模拟,并以电子支付系统中的可分电子现金为例讨论 上数字签名的应用,其安全性是基于大数分解和有限 群 上计算离散对数的困难性。圆锥曲线 上的数字签名方案体现了圆锥曲线所具有的明文嵌入方便、运算速度快、更易于实现等优点。