LTL is closed under topological closure

We constructively prove that for every LTL formula φ, the smallest safety property containing the property expressed by φ is also expressible in LTL. It immediately follows that LTL admits the safety-liveness decomposition: any property expressed by an LTL formula is equivalent to the intersection of a safety property and a liveness property, both of them expressible in LTL. Our proof is based on constructing a minimal deterministic counter-free Büchi automaton that recognizes the smallest safety property containing the property expressed by φ.     

论虚拟财产的刑法保护

本文从犯罪论的角度分析了网络虚拟财产的法律属性,认为网络虚拟财产具有财产属性,可以作为盗窃罪的犯罪对象,盗窃网络虚拟财产具有社会危害性,应该适用《刑法》进行规制。     

The undecidability of self-embedding for term rewriting systems

The self-embedding property of term rewriting systems is closely related to the uniform termination property, since a nonself-embedding term rewriting system is uniform terminating. The self-embedding property is shown to be undecidable and partially decidable. It follows that the nonself-embedding property is not partially decidable. This is true even for globally finite term rewriting systems. The same construction gives an easy alternate proof that uniform termination is undecidable in general and also for globally finite term rewriting systems. Also, the looping property is shown to be undecidable in the same way.     

时间属性序列图:语法和语义

为了表示事件出现的时间约束,扩展属性序列图为时间属性序列图,使其继承属性序列图的优点,并且能够表示时间属性,定义了时间属性序列图的形式语法,并给出基于时间Büchi自动机的形式操作语义;用实时规约模式度量了时间属性序列图的表达力。最后,对时间属性序列图进行了实例研究,显示了其广泛的应用前景。     

Generalizing constraint satisfaction on trees: Hybrid tractability and variable elimination

The Constraint Satisfaction Problem (CSP) is a central generic problem in artificial intelligence. Considerable progress has been made in identifying properties which ensure tractability in such problems, such as the property of being tree-structured. In this paper we introduce the broken-triangle property, which allows us to define a novel tractable class for this problem which significantly generalizes the class of problems with tree structure. We show that the broken-triangle property is conservative (i.e., it is preserved under domain reduction and hence under arc consistency operations) and that there is a polynomial-time algorithm to determine an ordering of the variables for which the broken-triangle property holds (or to determine that no such ordering exists). We also present a non-conservative extension of the broken-triangle property which is also sufficient to ensure tractability and can also be detected in polynomial time.We show that both the broken-triangle property and its extension can be used to eliminate variables, and that both of these properties provide the basis for preprocessing procedures that yield unique closures orthogonal to value elimination by enforcement of consistency. Finally, we also discuss the possibility of using the broken-triangle property in variable-ordering heuristics.     

银行账户交易复杂网络特性分析

首先基于银行账户交易的特点，建立了一个有向加权的银行账户交易网络通用模型。进而，根据复杂网络的定义，从网络结构和节点2个层面，验证了交易网络的复杂网络特性。其中，网络结构特性包括静态特性（即无标度特性和小世界特性）和动态演化特性（即自组织特性）。此外，使用吸引子特性验证了复杂网络节点的动力学特征。分析包含非法传销交易的真实银行交易数据，得出如下结论：该网络具有无标度特性、小世界特性、部分自组织特性和奇异吸引子。     

大图中子图的可测性质

对于给定的距离参数。,性质测试算法A需以高概率正确地区分给定的对象具备预定性质II与二远离性质 II。若存在II的测试算法A满足其询问复杂性独立于规模参数n,则称II是可测的。设H是一个图,性质仔了)℃。为 不含井子图的图所构成的集合。在有界度模型中,Goldreich与Ron证明了对任意连通图H,性质仔力℃。是可测 的}s}。在邻接矩阵模型中,证明了对任意图H,不管其连通与否,性质件厂re。是可测的。     

控制网络的实时性分析

本文通过对控制网络的实时性进行了分析,指出了影响控制网络实时性的主要因素,并提出了提高网络实时性应采取的方法.     

基于属性结构的本体映射方法

提出基于本体概念属性结构的本体映射方法。从多角度提取本体属性的描述特征,综合处理本体之间属性的映射,形成2个本体共同的属性结构树。利用属性结构树寻找概念属性的层次关系,以度量本体概念间的语义相似度。实验结果表明,属性结构是影响本体映射的因素之一,该方法有效。     

Defining liveness

A formal definition for liveness properties is proposed. It is argued that this definition captures the intuition that liveness properties stipulate that ‘something good’ eventually happens during execution. A topological characterization of safety and liveness is given. Every property is shown to be the intersection of a safety property and a liveness property.     

Flaw and modification of the iKP electronic payment protocols

We found that the 2KP/3KP electronic payment protocols as well as the 1KP electronic payment protocol do not possess a probably important property. The property is that if an acquirer authorizes a payment, then both the buyer and seller concerned always agree on it, which is called agreement property in this article. We also propose a modification to have 2KP/3KP possess the property.     

基于网络微积分的WSNs属性界限研究

研究表明:传统的无线传感器网络(WSNs)属性界限过于宽松。为此,基于网络微积分,改进了流经节点的数据流输出函数上界,并推导出更精确的WSNs属性界限,包括节点延迟上界、节点缓冲区容量下界以及节点服务速率下界等。数值分析结果表明:网络跳数越多、节点梯度越小,则传统属性界限与属性界限差异越大。这说明网络规模越大,按属性界限进行网络配置能节约更多资源。     

3D property research from a legal perspective

This article investigates and discusses 3D property research, as evidenced by conference papers and other publications written in English, to analyze the distribution of interest areas and the occurrence of legal aspects and trends within 3D property research occurring between 2001 and 2011. A total of 156 publications on 3D property were examined. The publications were classified in four different categories, which represent different aspects of 3D property: legal, technical, registration and organizational. More 3D property research has been conducted on technical aspects and registration than legal aspects. In the legal category, most studies addressed national legislation and the practical use of (national) legislation. The authors believe that further fundamental legal research on 3D property is needed. The quantity of research could be increased, for example, by promoting international discussion and increasing the number of comparative legal studies on 3D property rights. Additional and more focused attention should be given to international matters, such as comparative studies on the use of 3D property concepts, the development of (international) 3D property terminology and cooperation between 3D property unit owners.     

几种满足汇合性质的Petri网子类

证明活的标识S-图、活的标识T-图、有界的冲突无关的Petri网、有界的标识T．图具有汇合性质,讨论共享合成与同步合成操作对Petri网汇合性质的保持性,得出由上述简单的Petri网子类通过共享合成及同步合成得到的复杂的网系统也具有汇合性质。通过一个具有汇合性质的复杂网系统实例验证该结论。     

二元关系的性质测试及其复杂性分析

本文介绍了性质测试的基本原理,分析了用性质测试方法解决参数化问题的可行性,并将同构性质进行了参数化。研究了二元关系的性质测试以及参数化框架同构性质的测试问题,对固定的距离参数,证明了测试复杂性低于标准判定程序的复杂性。     

基于双线性对签密的安全高效远程证明协议

为了解决当前远程证明方案中安全性差、效率较低的问题,提出了一种安全高效的模块级远程证明协议。该协议在构建模块属性签名时采用了签密方案,减少了属性证书的生成时间;而且采用椭圆曲线上基于双线性对的签密方案,同时也大大提高了属性证书的安全性。通过实验验证了协议的可行性。实验结果表明,该方案可以快速生成可信平台中各模块的属性签名,提高了远程证明的效率     

本体解析的应用研究

详细描述了如何用Jena2解析本体,包括OWL文件中本体模型的载入,类、子类、实例、对象属性、值属性的提取,以及如何找到某一对象属性相关联的约束值等。     

基于EPMM的软件过程性质合理性研究

为提高软件演化的质量和效率、缩短软件演化的周期,有必要对软件演化所涉及的软件过程进行性质合理性研究,以确保软件演化过程的正确性。根据软件演化过程元模型(EPMM)的过程层定义,提出EPMM性质合理性的形式定义,用于确保软件过程在实施执行中应满足的动态性质,并基于Petri网的可达图,设计相应的性质合理性检验算法。应用结果表明,对软件演化过程进行性质合理性检验可以确保过程逻辑不发生异常,满足过程定义性质方面的正确性要求。     

Probabilistic techniques for intrusion detection based on computeraudit data

This paper presents a series of studies on probabilistic properties of activity data in an information system for detecting intrusions into the information system. Various probabilistic techniques of intrusion detection, including decision tree, Hotelling's T² test, chi-square multivariate test, and Markov chain are applied to the same training set and the same testing set of computer audit data for investigating the frequency property and the ordering property of computer audit data. The results of these studies provide answers to several questions concerning which properties are critical to intrusion detection. First, our studies show that the frequency property of multiple audit event types in a sequence of events is necessary for intrusion detection. A single audit event at a given time is not sufficient for intrusion detection. Second, the ordering property of multiple audit events provides additional advantage to the frequency property for intrusion detection. However, unless the scalability problem of complex data models taking into account the ordering property of activity data is solved, intrusion detection techniques based on the frequency property provide a viable solution that produces good intrusion detection performance with low computational overhead     

一种混沌Hopfiele网络及其在优化计算中的应用

文章讨论了神经网络算法在约束优化问题中的应用,提出了一种混沌神经网络模型。在Hopfield网络中引入混沌机制,首先在混沌动态下搜索,然后利用HNN梯度优化搜索。对非线性函数的优化问题仿真表明算法具有很强的克服陷入局部极小能力。