Fuzzy reasoning morphological operators and their optical implementation

Fuzzy-reasoning theory is widely used in industrial control. Mathematical morphology is a powerful tool to perform image processing. We apply fuzzy-reasoning theory to morphology and suggest a scheme of fuzzy-reasoning morphology, including fuzzy-reasoning dilation and erosion functions. These functions retain more fine details than the corresponding conventional morphological operators with the same structuring element. An optical implementation has been developed with area-coding and thresholding methods. (C) 1997 Optical Society of America.

A logic for default reasoning

The need to make default assumptions is frequently encountered in reasoning about incompletely specified worlds. Inferences sanctioned by default are best viewed as beliefs which may well be modified or rejected by subsequent observations. It is this property which leads to the non-monotonicity of any logic of defaults. In this paper we propose a logic for default reasoning. We then specialize our treatment to a very large class of commonly occuring defaults. For this class we develop a complete proof theory and show how to interface it with a top down resolution theorem prover. Finally, we provide criteria under which the revision of derived beliefs must be effected.

关于吸气式高超声速推进技术研究的思考

回顾了吸气式高超声速推进技术的研究进展,分析了超燃冲压发动机研制面临的关键科学问题,并从不同角度探讨了增大超燃冲压发动机推力的可能方法.这些方法包括:能够降低总压损失的高超声速来流压缩方法、生成三维涡流的超声速混合增强技术、碳氢燃料的预热喷射、可以控制燃烧过程的燃烧室设计优化方法、通过减小发动机流道湿面积来降低摩擦阻力和催化复合解离的燃气降低高温气体效应.考虑到等压热力学循环的热效率,还建议研究在高超声速推进系统中应用热效率高的爆轰过程,并探讨了爆轰推进方法研究的进展与问题.吸气式高超声速推进技术是高超声速飞行器发展的关键技术,认真思考和探索其发展方向是非常必要的.

Fuzzy inferring mathematical morphology and optical implementation

Fuzzification is introduced into gray-scale mathematical morphology by using two-input one-output fuzzy rule-based inference systems. The fuzzy inferring dilation or erosion is defined from the approximate reasoning of the two consequences of a dilation or an erosion and an extended rank-order operation. The fuzzy inference systems with numbers of rules and fuzzy membership functions are further reduced to a simple fuzzy system formulated by only an exponential two-input one-output function. Such a one-function fuzzy inference system is able to approach complex fuzzy inference systems by using two specified parameters within it-a proportion to characterize the fuzzy degree and an exponent to depict the nonlinearity in the inferring. The proposed fuzzy inferring morphological operators tend to keep the object details comparable to the structuring element and to smooth the conventional morphological operations. Based on digital area coding of a gray-scale image, incoherently optical correlation for neighboring connection, and optical thresholding for rank-order operations, a fuzzy inference system can be realized optically in parallel. (C) 1996 Society of Photo-Optical Instrumentation Engineers.

Trace theory

The concept of traces has been introduced for describing non-sequential behaviour of concurrent systems via its sequential observations. Traces represent concurrent processes in the same way as strings represent sequential ones. The theory of traces can be used as a tool for reasoning about nets and it is hoped that applying this theory one can get a calculus of the concurrent processes anologous to that available for sequential systems. The following topics will be discussed: algebraic properties of traces, trace models of some concurrency phenomena, fixed-point calculus for finding the behaviour of nets, modularity, and some applications of the presented theory.

basic research in computer science and software engineering at sklcs

The State Key Laboratory of Computer Science (SKLCS) is committed to basic research in computer science and software engineering. The research topics of the laboratory include: concurrency theory, theory and algorithms for real-time systems, formal specifications based on context-free grammars, semantics of programming languages, model checking, automated reasoning, logic programming, software testing, software process improvement, middleware technology, parallel algorithms and parallel software, computer graphics and human-computer interaction. This paper describes these topics in some detail and summarizes some results obtained in recent years.

语义网的一阶逻辑推理技术支持

研究了一阶逻辑推理工具对语义网的推理支持.语义网的关键推理问题可以化为公式的可满足性判定问题.一阶逻辑的自动定理证明器可以证明不可满足性,而有限模型查找器为可满足的公式在有限域内构造模型.提出在语义网的推理中,同时使用定理证明器和有限模型查找器.实验结果表明,这样可以解决描述逻辑工具的不足,并可以弥补定理证明器对可满足的公式推理的不完备性.

constructing finite algebras with falcon

The generation of models and counterexamples is an important form of reasoning. In this paper, we give a formal account of a system, called FALCON, for constructing finite algebras from given equational axioms. The abstract algorithms, as well as some implementation details and sample applications, are presented. The generation of finite models is viewed as a constraint satisfaction problem, with ground instances of the axioms as constraints. One feature of the system is that it employs a very simple technique, called the least number heuristic, to eliminate isomorphic (partial) models, thus reducing the size of the search space. The correctness of the heuristic is proved. Some experimental data are given to show the performance and applications of the system.

基于贝叶斯网络近似推理的网络脆弱性评估方法

针对大规模计算机网络的脆弱性评估,提出了一种基于贝叶斯网络近似推理的评估方法,对网络各组件和影响网络安全的因素进行建模,采用模型检测工具生成攻击状态转移图,描述网络脆弱性的利用过程,通过采用随机采样的方法对网络的攻击状态转移图进行近似推理,经过对采样样本的统计分析得到网络脆弱性评估的量化结果,为提升网络的安全性能提供理论依据。

密码协议的一种基于组合推理的模型验证

将密码协议与协议中用到的密码算法视为一个系统,基于组合推理技术建立了密码协议系统的形式化模型。采用基于假设/保证的组合推理技术提出了新的假设/保证推理规则和假设/保证推理算法,证明了该规则的正确性,实现了密码协议系统的模型验证,并重点解决了系统分解问题、假设函数的设定问题等难题。以kerberos v5密码协议系统为例,利用该组合推理技术对密码协议系统进行了安全验证。1

基于非确定性推理的网构软件服务质量动态评估方法

提出了网构软件环境下一种基于非确定性推理的构件服务质量动态评估方法，该方法基于贝叶斯网络，其主要特点在于考虑了用户对构件的QoS需求，可以预测在用户多种QoS需求下采用分级策略的构件服务能力，支持评估模型的动态更新，提高了评估结果的准确性，在自主开发的服务协同总线（Once-SCB）平台上进行了应用与验证，结果表明，该评估模型准确、有效，可以在用户多种QoS需求下为其选择最为合适的构件。