一个基于Internet安全电子商务系统的安全机制设计与实现

本文介绍了我们已经实现的一个基于Internet的安全电子商务系统,它已成功地嵌入到当前流行的Netscape浏览器和服务器中,本文主要讨论了基于涉及基于设计级的安全需求,系统体系结构,系统功能和使用的关键技术,全安机制的设计和实现是我们的重点。     

A Wavelet Packet Algorithm for Classification and Detection of Moving Vehicles

In this paper we propose a robustalgorithm that solves two related problems: 1) Classificationof acoustic signals emitted by different moving vehicles. Therecorded signals have to be assigned to pre-existing categoriesindependently from the recording surrounding conditions. 2) Detectionof the presence of a vehicle in a certain class via analysisof its acoustic signature against the existing database of recordedand processed acoustic signals. To achieve this detection withpractically no false alarms we construct the acoustic signatureof a certain vehicle using the distribution of the energies amongblocks which consist of wavelet packet coefficients. We allowno false alarms in the detection even under severe conditions;for example when the acoustic recording of target object is asuperposition of the acoustics emitted from other vehicles thatbelong to other classes. The proposed algorithm is robust evenunder severe noise and a range of rough surrounding conditions.This technology, which has many algorithmic variations, can beused to solve a wide range of classification and detection problemswhich are based on acoustic processing which are not relatedto vehicles. These have numerous applications.     

ElGamal数字签名方案的发展与应用

ElGamal数字签名方案作为目前最为重要的数字签名方案之一,极大地促进了现代密码学的发展。分析了几个主要的ElGamal型数字签名方案的优缺点,并阐述了ElGamal型数字签名方案的一些应用状况。     

基于量子密码的签名方案

本文首次研究了量子签名问题,并提出了一个基于对称密码体制的量子签名方案.所提出的量子签名方案利用量子力学中的Greenberger-Horne-Zeilinger(GHZ)三重态的相干特性实现对量子比特串的签名和验证.研究表明本文提出的量子签名方案具有可证明安全性.     

Nondifferentiable Dynamic: Two Examples

Some nondifferentiable quantities (for example, the metric signature) can be the independent physical degrees of freedom. It is supposed that in quantum gravity these degrees of freedom can fluctuate. Two examples of such quantum fluctuation are considered: a quantum interchange of the sign of two components of the 5D metric and a quantum fluctuation between Euclidean and Lorentzian metrics. The first case leads to a spin-like structure on the throat of a composite wormhole and to a possible inner structure of the string. The second case leads to a quantum birth of the non-singular Euclidean Universe with frozen 5^th dimension. The probability for such quantum fluctuations is connected with an algorithmical complexity of the Einstein equations.     

Eu超形变带的自旋指定

系统分析了^{142,143,144,147}Eu中的8条超形变带.在对跃迁能量进行光滑化处理,采用ab拟合或改进的ab拟合,确切地指定了其中7条超形变带的自旋值.首次指出了147Eu的1,5两带和2,3两带可能都分别构成旋称伙伴带,且均为K=1/2带,脱耦合常数约为–1.讨论了它们可能的组态结构.     

Cryptography in Quadratic Function Fields

We describe severalcryptographic schemes in quadratic function fields of odd characteristic.In both the real and the imaginary representation of such a field,we present a Diffie-Hellman-like key exchange protocol as wellas a public-key cryptosystem and a signature scheme of ElGamaltype. Several of these schemes are improvements of systems previouslyfound in the literature, while others are new. All systems arebased on an appropriate discrete logarithm problem. In the imaginarysetting, this is the discrete logarithm problem in the idealclass group of the field, or equivalently, in the Jacobian ofthe curve defining the function field. In the real case, theproblem in question is the task of computing distances in theset of reduced principal ideals, which is a monoid under a suitableoperation. Currently, the best general algorithms for solvingboth discrete logarithm problems are exponential (subexponentialonly in fields of high genus), resulting in a possibly higherlevel of security than that of conventional discrete logarithmbased schemes.     

一种信号分选和特征提取联合处理的雷达信号分析方法研究

研究广度优先搜索邻居的聚类算法和直方图法用于雷达信号分选和特征提取的原理和方法,并将两者相结合用于雷达信号分析使分选和特征提取更加准确.仿真实验证明联合处理法是高效和实用的.     

Multi-proxy quantum group signature scheme with threshold shared verification

A multi-proxy quantum group signature scheme with threshold shared verification is proposed. An original signer may authorize a proxy group as his proxy agent. Then only the cooperation of all the signers in the proxy group can generate the proxy signature on behalf of the original signer. In the scheme, any t or more of n receivers can verify the message and any t - 1 or fewer receivers cannot verify the validity of the proxy signature.     

一种基于群签名的分布式洋葱路由

洋葱路由技术是指一个在公用网络上广泛运用的基于P2P的匿名通信技术,它使得攻击者既不能进行窃听,也不能实施流量分析,实现了信息发送者和接收者的匿名性,也保护了信息内容本身的安全。针对当下洋葱路由实现的基本模型,结合群签名技术和分布式的概念,文中提出了一种基于群签名的分布式洋葱路由方案,并对其性能做了简单的分析,证明确实在路径的隐蔽性、系统的安全性等方面都有了较好的提升。