A hybrid scheme for action representation

Strong deficiencies are present in symbolic models for action representation and planning, regarding mainly the difficulty of coping with real, complex environments. These deficiencies can be attributed to several problems, such as the inadequacy in coping with incompletely structured situations, the difficulty of interacting with visual and motorial aspects, the difficulty in representing low-level knowledge, the need to specify the problem at a high level of detail, and so on. Besides the purely symbolic approaches, several nonsymbolic models have been developed, such as the recent class of subsym-bolic techniques. A promising paradigm for the modeling of reasoning, which combines features of both symbolic and analogical approaches, is based on the construction of analogical models of the reference for the internal representations, as introduced by Johnson-Laird. In this work, we propose a similar approach to the problem of knowledge representation and reasoning about actions and plans. We propose a hybrid approach, symbolic and analogical, in which the inferences are partially devolved to measurements on analogical models generated starting from the symbolic representation. the interaction between the symbolic and the analogical level is due to the fact that procedures are connected to some symbols, allowing generating, updating, and verifying the mental model. the hybrid model utilizes, for the symbolic component, a representation system based on the distinction between terminological and assertional knowledge. the terminological component adopts a SI-Net formalism, extended by temporal primitives. the assertional component is a subset of first-order logics. the analogical representation is a set of concurrent procedures modeling parts of the world, action processes, simulations, and metaphors based on force fields concepts. A particular case study, regarding the problem of the assembly of a complex object from parts, is taken as an experimental paradigm. © 1993 John Wiley Sons, Inc.     

模糊面向对象数据模型的描述逻辑表示与推理

通过分析描述逻辑与面向对象数据模型之间的关系,研究了基于描述逻辑的模糊面向对象数据(fuzzy object-oriented data,简称FOOD)模型的表示与推理.首先,进一步研究了FOOD模型,提出了FOOD模型的形式化定义和语义定义,以便更好地在FOOD模型与模糊描述逻辑之间建立对应关系;然后,针对FOOD模型的特点和推理需求,介绍了模糊描述逻辑f-ALCIQ.在此基础上,研究了基于f-ALCIQ的FOOD模型的表示与推理,包括:实现了从FOOD模型到f-ALCIQ知识库在结构层和实例层上的转化,即实现了从FOOD模型到f-ALCIQ TBox的转化,以及从FOOD模型相应的数据库实例到f-ALCIQ ABox的转化;进而,基于转化得到的f-ALCIQ知识库,研究了如何利用f-ALCIQ的推理机制对FOOD模型的推理问题(一致性、包含性和冗余性等)进行推理;最后,设计并实现了基于f-ALCIQ的模糊描述逻辑推理机(FRsQ推理机),实现了对FOOD模型和f-ALCIQ模糊概念知识的自动推理.     

A UNITY-style programming logic for shared dataspace programs

A proof system for a shared dataspace programming notation called Swarm (a programming logic similar in style to that of UNITY) is specified. Relevant aspects of the Swarm language and model are overviewed. To illustrate the proof system, the Swarm logic is used to verify the correctness of a program for labeling connected equal-intensity regions of a digital image. Like UNITY, the Swarm proof system uses an assertional programming logic which relies upon proof of programwide properties, e.g. global invariants and progress properties. The Swarm logic is defined in terms of the same logical relations as UNITY (unless, ensures, and leads-to), but several of the concepts are reformulated to accommodate Swarm's distinctive features     

一种MAS构件知识复用动态演化模型

为提高企业的知识利用效率,增强企业创新能力,针对企业现有知识和系统,提出将企业知识管理的业务逻辑与知识处理事务分开,建立了基于多智能体和构件知识的知识复用模型,设计了知识管理业务逻辑的规则模型和智能体的活动行为模型,讨论了基于多智能体的规则协调模式,有效地支持知识的动态复用和知识使用过程的动态重组,增强知识管理系统的分布式处理能力和规模可扩展能力.在分布式构件库系统中,智能体通过协作联合完成任务要求.每个智能体拥有自己的知识库,并且具备学习能力,能够更新其知识库以保持执行结果的有效性.     

Logic-based process diagnosis utilising the causal structure of dynamical systems

A method for logic-based process diagnosis is proposed that utilise the causal structure of the dynamic system unter consideration to restrict the search space of the resolution system. The basis for this is given by a qualitative model of the dynamical process, which is formulated in assertional logic formulae, as well as a causality graph, which describes the directions of the cause-effect relations. It is shown that the overall diagnosis problem can be decomposed into a series of subproblems such that the solution of the subproblems is necessary and sufficient for the solution of the overall problem. This decomposition reduces the search space considerably and makes the diagnosis algorithm applicable under real-time constraints.     

布尔算子模糊逻辑中一种新的假说修正方法

在基于具有某种程度的不一致性的知识进行推理的过程中，为了消除知识的不一致性，只能将这些知识看成假说，并通过对假说进行修正以重新获得一个一致的假说。文中基于布尔算子模糊逻辑，给出了一种新的假说修正方法，这种方法能够在一定程度上更多地保留被修正知识的合理成分，以便在以后有机会得到恢复。     

基于描述逻辑的模糊ER模型

分析了描述逻辑ALNUI与ER模型的关系,特别是如何将ER模型转化为ALNUI的知识库,从而利用ALNUI的推理机制对ER模型进行自动推理的有效性,在此基础上,进一步研究了基于描述逻辑的模糊ER模型.针对模糊ER模型的特点和需求,在描述逻辑ALNUI的基础上,对描述逻辑ALNUI进行了模糊化推广,提出了一种新的描述逻辑,即模糊描述逻辑FALNUI.研究了基于FALNUI的模糊ER模型,即研究了如何将模糊ER模型转化为FALNUI的知识库,并利用FALNUI的推理机制研究了模糊ER模型的可满足性、冗余性和包含关系等自动推理问题,证明了这些推理问题的正确性.     

A Partial Order Approach to Branching Time Logic Model Checking

Partial order techniques enable reducing the size of the state space used for model checking, thus alleviating the “state space explosion” problem. These reductions are based on selecting a subset of the enabled operations from each program state. So far, these methods have been studied, implemented, and demonstrated for assertional languages that model the executions of a program as computation sequences, in particular the linear temporal logic. The present paper shows, for the first time, how this approach can be applied to languages that model the behavior of a program as a tree. We study here partial order reductions for branching temporal logics, e.g., the logics CTL and CTL* (with the next time operator removed) and process algebra logics such as Hennesy–Milner logic (withτactions). Conditions on the selection of subset of successors from each state during the state-space construction, which guarantee reduction that preserves CTL* properties, are given. The experimental results provided show that the reduction is substantial.     

MODELING TIMED BEHAVIOR IN REAL-TIME SYSTEMS WITH TEMPORAL LOGIC

This article presents graphic as well as assertional representations of the timed behavior of a real-time system. It introduces finite, directed, labeled graphs called temporal I/O automata (TA_i/o) to provide a visual means of modeling system behavior. A real-time system is modeled as a collection of communicating TA_i/os. A TA_i/o is associated with an external clock, which makes it possible to formulate hard, real-time constraints on actions performed by a system. Timing constraints provide control engineers with a means of measuring the responsive ness of a system to its environment. This article suggests how real-time temporal logic can be used to describe system behavior concisely. Temporal specifications provide (1) a means of verifying the; correctness of a system design, and (2) a basis for constructing implementations of system designs. The behavior of control systems for autonomous vehicles guided by visual feedback are described graphically with TA_i/oS and textually with temporal logic formulas. Suggestions on how such control systems can be implemented in distributed Ada are also presented.     

Reasoning with propositional knowledge based on fuzzy neural logic

In this article, a new kind of reasoning for propositional knowledge, which is based on the fuzzy neural logic initialed by Teh, is introduced. A fundamental theorem is presented showing that any fuzzy neural logic network can be represented by operations: bounded sum, complement, and scalar product. Propositional calculus of fuzzy neural logic is also investigated. Linear programming problems risen from the propositional calculus of fuzzy neural logic show a great advantage in applying fuzzy neural logic to answer imprecise questions in knowledge-based systems. An example is reconsidered here to illustrate the theory. © 1996 John Wiley & Sons, Inc.     

Knowledge Representation of Software Component Interconnection Information for Large-Scale Software Modifications

Logic can be used to precisely express human thoughts and inferences. In this paper, an approach using first-order logic for knowledge representation of software component interconnection information to facilitate the validity and integrity checking of the interconnection among software components during software development or modification is presented. Directed graphs are first used to model the structure and behavior of a large-scale software system, and a first-order theory of directed graphs (the DG theory) is established. The interconnection behavior among software components in a large-scale software system is a directed graph which is called software component interconnection graph (CIG). The behavior of the CIG is interpreted using the DG theory and translated into logic representation. The translated logic representation is a set of logic clauses and can be considered as a set of axioms. Automated reasoning techniques based on these axioms can be used to perform the validity and integrity checking of software properties in the software development or maintenance phase.     

基于生态学的复杂系统稳定性逻辑分析模型

复杂系统的稳定性是众多学科所关注的问题。根据生态平衡的理论，从人工智能、自然智能、智能逻辑和数学的角度，给出了一个基于生态学的复杂系统稳定性逻辑分析模型，并进行了严格的推理论证，从而为分析和解决复杂系统的稳定性问题提供了一个有力的工具，也为复杂系统理论增添了新的内容。     

基于模态缺省理论的多Agent系统的知识更新

基于模态缺省理论，建立多Agent系统的模态缺省逻辑，给出了每个主体 对应的模态缺省理论 的新知识和知识冲突的概念及其意义，主要讨论在多Agent环境下，当一个Agent的知识不足以完成推理时，可以从其它Agent处获得新的知识，从而对自身的信念集进行更新。当Wi发生变化(如遇到新的知识或出现与原信念集冲突的知识)时扩充Ei的性质和变化规律，提出了获取新扩充的较简单的求解方法，并证明了相关的定理，给出了多Agent系统的关于知识的一个动态描述过程。     

A Knowledge-based System with Audio-Visual Aids

A Knowledge-based System with Audio-Visual Aids (KS/AV) is presented. KS/AV is a knowledge-based system that has multiple types of knowledge represented not only in symbols but in audio-visual (AV) images, and it provides an environment for humanmachine communication through AV media. We define a predicate logic based on objects for knowledge representation in KS/AV. It is a first order predicate logic in which every individual is regarded as an object. All of the individuals including AV images are regarded as objects. Their definitions are based on the class concepts of Smalltalk-80. AV image objects presented in this paper include not only simple video and graphic images, but also composite images that consist of several component images. This paper presents the KS/AV system developed on a small computer system with various AV equipment. As a case study, we developed a reading advisory system for children on KS/AV, which communicates with children through AV images and gives their favourite picture books.     

A conceptual model of service customization and its implementation

With the development of Internet and next generation networks in telecommunications, more and more new services are required to be introduced into networks. Introducing new services into traditional network is always associated with standardizing new protocols. The progress of protocol standardization usually takes several years, which cannot meet the increasing demands of the applications in Internet and next generation networks. Service customization in network systems may be one possible solution to cope with this problem. Based on the principle that network service is provided by interactions among protocol entities, this paper proposes a conceptual model of service customization (SECUM) by separating the service logic from protocol interactive logic within existing network architecture. The theory of Communicating Sequential Processes (CSP) is used to formalize the SECUM in order to locate exactly the service logic and to define precisely the SECUM. For validating the SECUM‘s usability in practical network systems, this paper also proposes an implementation model for SECUM: a component-based protocol implementation model (CPIM). CPIM discomposes protocol entity into application component, service component, message component and communication component. Service component associates application component with message component. Users or network managers can customize network services by configuring service component. The paper shows respectively the applications of SECUM and CPIM by proposing a customizable IP service model based on SECUM and describing an implementation of Session Initiation Protocol (SIP) based on CPIM. Compared with the existing service-customization techniques, SECUM is a service customization model internal to network system and may provide more powerful capabilities of service customization.     

Making the knowledge base systems more efficient: a method todetect inconsistent queries

The processing cost of queries with an empty answer, both in the database and knowledge base context, is usually high. One purpose of semantic query optimization methods in the database context is to use semantic knowledge to detect such types of queries. Although semantic query optimization is well known in the database context, this is not the case for knowledge base systems (KBSs). This paper presents a method that allows the detection of queries with an empty answer using only semantic information expressed in the knowledge base definition. The method can be applied in the context of KBSs that provide some of the following features: structuring mechanisms, assertional knowledge, temporal information, and handling of inequality expressions     

Web服务的形式化验证

将Web服务组合建模为多智能体系统,采用时态知识逻辑模型检测工具MCTK刻画贷款协议Web服务实例,并验证相关的时态知识规范。在同一实验环境下,采用另一种时态知识逻辑模型检测工具MCMAS进行建模,并验证该实例。实验结果表明,基于MCTK的Web服务模型检测方法比基于MCMAS的方法更有效。