超协调限制逻辑

本文给出了一阶超协调限制逻辑ＬＰｓ的定义，并证明了它与悖论逻辑（ＬＰ与ＬＰｍ）和限制逻辑（ＣＩＲＣ）的关系，ＬＰ作为一种非单调超协调逻辑具有非单逻辑和超协调逻辑的优点，而用能解决非单调逻辑和超协调逻辑存在的问题，它可作为在不完全与不协调知识下常识推理的形式化，因此它的知识表示中具有广泛的应用。     

一个在费协调逻辑中的限制

本通过应用限制到一个费协调逻辑给出一种费协调限制，费协调限制是一种费协调非单调逻辑，它能被极小化语义所刻划，并具有两方面优点：非单调逻辑在包含矛盾时是不平凡的；费协调逻辑在矛盾没有影响时等介于经典逻辑。     

超协调逻辑（Ⅳ）—非单调超协调逻辑研究

这是关于超协调逻辑研究的末篇，文中分析了超协调逻辑与非单调逻辑的关系，并提出非单调超协调逻辑作为一种新的逻辑研究及其在形式化常识推理中的重要意义，最后，讨论了超协调逻辑的应用，特别是非单调超协调逻辑在计算机科学与人工智能中的应用问题。     

一个在弗协调逻辑中的限制

本文通过应用限制到一个弗协调逻辑给出一种弗协调限制，弗协调限制是一种弗协调非单调逻辑，它能被极小化语义所刻划，并具有两方面优点：非单调逻辑在包含矛盾时是不平凡的；弗协调逻辑在矛盾没有影响时等价于经典逻辑．     

一种带缺省推理的描述逻辑

该文提出了一种新的带缺省推理的描述逻辑，它以描述逻辑为主要框架，对单调逻辑和非单调逻辑进行了整合，但又避免了一般缺省逻辑的困难．基于带缺省推理的描述逻辑，构建了一种同时具有Tbox，Abox和缺省规则的知识库系统，研究了带缺省推理的描述逻辑的可满足性、缺省可满足性、概念包含、缺省包含以及实例检测等推理问题，提出了一种用来检测可满足性和缺省可满足性的Tableau—D算法，并得到了缺省可满足性和缺省包含的转换定理．     

超协调限制逻辑的计算复杂性分析

超协调限制逻辑LPc是一种同时具有非单调性和超协调性的非经典逻辑，它可作为在不完全与不协调知识下常识推理的形式化.给出了命题LPc的计算复杂性结果和算法实现，指出LPc是NP完全问题，并给出了将LPc转化为等价的优先限制逻辑的线性时间算法，由于限制逻辑具有实用的实现算法且可用归结方法实现，因而该算法为LPc的实现提供了新的途径.     

基于信度语义的算子模糊逻辑

本文在算子集与值域不同的算子格上，基于信度语义定义了一种归结推理更自然、具有结合性的算子模糊逻辑ＢＡＯＦＬ及一种语义有层次性的，非单调的算子模糊逻辑ＮＭＯＦＬ。     

非单调性和不一致性的处理——一个基于线性逻辑的方法

本文提出一种基于线性逻辑的理论L1,它除了能较好地反映常识推理的非单调性外,还可以在矛盾存在的情况下继续组织有效的推理。     

超协调逻辑（Ⅲ）—超协调性的逻辑基础

这是关于超协调逻辑研究的第三篇，文中将给出一种优先语义作为超协调性的模型论基础，并给出一种表演算系统作为超协调性的证明论基础，这种优先语义和表演算系统，不仅可以包括名种超协调逻辑，而且能够导出新的超协调逻辑，在一定意义上，是超协调逻辑的统一基础，容易统一地刻画非单调性。     

悖论逻辑及其表演算

悖论逻辑LP是一个超协调逻辑,极小悖论逻辑LPm是一个LP的非单调逻辑扩展.本文给出了一阶LP和LPm的表演算.为此,本文在论证了(极小)悖论逻辑语义性质基础上,首先给出一个LP的(记号)表演算,然后给出一个LPm的极小表演算,并证明了两个表演算分别对于LP和LPm语义的可靠与完全性定理.     

常识问题——常识推理的逻辑基础

本文主要讨论常识推理的逻辑基础，基于一条从非单调推理到常识推理的技术途径，由此指出在更一般意义上形式化常识推是的一些结果，它建立常识逻辑和解决常识问题提供了有用的基础工具。     

The Nature of Nonmonotonic Reasoning

Conclusions reached using common sense reasoning from a set of premises are often subsequently revised when additional premises are added. Because we do not always accept previous conclusions in light of subsequent information, common sense reasoning is said to be nonmonotonic. But in the standard formal systems usually studied by logicians, if a conclusion follows from a set of premises, that same conclusion still follows no matter how the premise set is augmented; that is, the consequence relations of standard logics are monotonic. Much recent research in AI has been devoted to the attempt to develop nonmonotonic logics. After some motivational material, we give four formal proofs that there can be no nonmonotonic consequence relation that is characterized by universal constraints on rational belief structures. In other words, a nonmonotonic consequence relation that corresponds to universal principles of rational belief is impossible. We show that the nonmonotonicity of common sense reasoning is a function of the way we use logic, not a function of the logic we use. We give several examples of how nonmonotonic reasoning systems may be based on monotonic logics.     

Default reasoning and belief revision: A syntax-independent approach

As an important variant of Reiter‘s default logic.Poole(1988) developed a nonmonotonic reasoning framework in the classical first-order language,Brewka and Nebel extended Poole‘s approach in order to enable a representation of priorities between defaults.In this paper a general framework for default reasoning is presented,which can be viewed as a generalization of the three approaches above.It is proved that the syntax-independent default reasoning in this framework is identical to the general belief revision operation introduced by Zhang et al.(1997).This esult provides a solution to the problem whether there is a correspondence between belief revision and default logic for the infinite case .As a by-product,an answer to the the question,raised by Mankinson and Gaerdenfors(1991),is also given about whether there is a counterpart contraciton in nonmonotonic logic.     

基于自动推理技术的智能规划方法

对几种智能规划方法中利用的逻辑演绎与推理技术予以分析,分别介绍利用命题逻辑的基于可满足性的规划方法与规划系统,利用模态逻辑与析取推理的Conformant规划方法与规划系统,利用非单调逻辑的规划方法和利用模糊描述逻辑的Flexible规划方法,并结合国际规划竞赛和相关论文等的实验结论说明上述方法的有效性和可行性.最后,提出目前基于自动推理技术的智能规划方法所面临的挑战、可能的处理方法以及与之相关的研究热点与趋势.     

Autoepistemic logic of first order and its expressive power

We study the expressive power of first-order autoepistemic logic. We argue that full introspection of rational agents should be carried out by minimizing positive introspection and maximizing negative introspection. Based on full introspection, we propose the maximal well-founded semantics that characterizes autoepistemic reasoning processes of rational agents, and show that breadth of the semantics covers all theories in autoepistemic logic of first order, Moore's AE logic, and Reiter's default logic. Our study demonstrates that the autoepistemic logic of first order is a very powerful framework for nonmonotonic reasoning, logic programming, deductive databases, and knowledge representation.This research is partially supported by NSERC grant OGP42193.     

An Interpretation of Default Logic in Minimal Temporal Epistemic Logic

When reasoning about complex domains, where information available is usually only partial, nonmonotonic reasoning can be an important tool. One of the formalisms introduced in this area is Reiter's Default Logic (1980). A characteristic of this formalism is that the applicability of default (inference) rules can only be verified in the future of the reasoning process. We describe an interpretation of default logic in temporal epistemic logic which makes this characteristic explicit. It is shown that this interpretation yields a semantics for default logic based on temporal epistemic models. A comparison between the various semantics for default logic will show the differences and similarities of these approaches and ours.     

A Critical Reexamination of Default Logic, Autoepistemic Logic, and Only Knowing

Fifteen years of work on nonmonotonic logic has certainly increased our understanding of the area. However, given a problem in which nonmonotonic reasoning is called for, it is far from clear how one should go about modeling the problem using the various approaches. We explore this issue in the context on two of the best–known approaches, Reiter's default logic and Moore's autoepistemic logic, as well as two related notions of "only knowing," due to Halpern and Moses and to Levesque. In particular, we return to the original technical definitions given in these papers and examine the extent to which they capture the intuitions they were designed to capture.     

Operational Concepts of Nonmonotonic Logics Part 2: Autoepistemic Logic

The subject of nonmonotonic reasoning is reasoning with incompleteinformation. One of the main approaches is autoepistemic logic inwhich reasoning is based on introspection. This paper aims at providing a smooth introduction to this logic,stressing its motivation and basic concepts. The meaning (semantics)of autoepistemic logic is given in terms of so-called expansionswhich are usually defined as solutions of a fixed-point equation. Thepresent paper shows a more understandable, operational method fordetermining expansions. By improving applicability of the basicconcepts to concrete examples, we hope to make a contribution to awider usage of autoepistemic logic in practical applications.     

Equilibrium logic

Equilibrium logic is a general purpose nonmonotonic reasoning formalism closely aligned with answer set programming (ASP). In particular it provides a logical foundation for ASP as well as an extension of the basic syntax of answer set programs. We present an overview of equilibrium logic and its main properties and uses.Partially supported by CICyT project TIC-2003-9001-C02, URJC project PPR-2003-39 and WASP (IST-2001-37004).