共查询到20条相似文献,搜索用时 15 毫秒
1.
多主体系统是当前人工智能研究后一个热点,其中,关于知识和动作的推理是一个重要的课题,文中给出了一种知识表示框架,称为RAO逻辑,用来对其它主体研究时表示概念和规则,我们从日常推理中抽象出换位原则的规则(PEP),PEP是RAO是的一条公理模式,并且为主体研究其它主体的一个基本规则,它与知识逻辑中的分离规则和(K)公理具有相似的形式和作用。 相似文献
2.
A formal approach is presented for proving temporal properties of dynamic systems. Its main advantage is that it can be used to prove properties of hybrid systems, i.e. those whose state contains both discrete and continuous parameters. In contrast, most current temporal reasoning techniques are restricted either to purely discrete systems or to purely continuous systems. Our approach is based upon a new modeling technique called DMOD. A DMOD model of a system defines the causality relation between events in the system, using definite clauses, i.e. logic programs. Thereby, the problem of reasoning about hybrid systems is reduced to one of reasoning about the behavior of definite clauses. As these possess a simple proof theory, reasoning is substantially simplified. 相似文献
3.
Allen's interval algebra has been shown to be useful for representing plans. We present a strengthened algorithm for temporal reasoning about plans, which improves on straightforward applications of the existing reasoning algorithms for the algebra. This is made possible by viewing plans as both temporal networks and hierarchical structures. The temporal network view allows us to check for inconsistencies as well as propagate the effects of new temporal constraints, whereas the hierarchical view helps us to get the strengthened results by taking into account the dependency relationships between actions. We further apply our algorithm to the process of plan recognition through the analysis of natural language input. We show that such an application has two useful effects: the temporal relations derived from the natural language input can be used as constraints to reduce the number of candidate plans, and the derived constraints can be made more specific by combining them with the prestored constraints in the plans being recognized. 相似文献
4.
本文首先介绍了动态系统的定性推理的产生背景,发展概况以及定性推理的实际应用前景,然后以Kuipers的定性仿真理论为中心介绍了定性推理的基本原理及方法,其中重点介绍了动态定性仿真算法QSIM和定性推理的最新发展,并对存在的问题进行了探讨。 相似文献
5.
This paper presents a new algorithm for dealing with inexact reasoning problems, where the certainty factors of the rules and the truth values of the conditions appearing in the rules are represented by linguistic terms. The algorithm performs inexact reasoning via repeatedly transforming an augmented linguistic truth state vector T by an augmented linguistic rule matrix F. Given the linguistic truth values of some conditions, the algorithm can perform inexact reasoning to evaluate the linguistic truth values of other conditions automatically. 相似文献
6.
本文提出了一个基于定时的Petri网和立方体队列网络的实时多任务系统的建模方法-TPCQ,它特别适合于描述含有同步、通信和立方体队列调度的复杂的实时多任务系统,也可以描述一般的实时多任务系统。文中讨论了TPCQ模型,并且给出了一个建立实时多任务系统的TPCQ模型的例子。 相似文献
7.
This article presents layer types as a concept for modeling arrays of communication objects. In a sense, layer types can be considered a generalization of array types. If the components of a layer are of a class type, the identifiers of component fields and methods can be lifted to the layer type level such that the lifted identifiers can be used to access all respective layer fields or layer methods by dot notation. This facilitates usual programming tasks. In addition, by employing predefined layer methods based on flags, functions, and relations over indices, layer types open up the way for a flexible and concise modeling of networks of communicating objects. 相似文献
8.
This paper describes the implementation of WQMS, a general-purpose qualitative modeling environment that integrates the process-centered approach and the constraint-centered approach. A new simulation algorithm is presented in which, owing to this integration, some drawbacks of QSIM are overcome using a depth-first strategy in the assessment of the qualitative states and a reduced set of input variables. With this algorithm it is possible to achieve qualitative simulations in cases in which simulations by QSIM are not feasible, because in some complex systems it is possible neither to specify the initial conditions for all required variables nor to handle the amount of branching that arises with normal computer facilities. An implementation of modeling and simulation of two biological systems is shown; to the best of the authors' knowledge, WQMS is the only environment with which a qualitative simulation can be achieved for these systems. 相似文献
9.
Functional models have been extensively investigated in the context of several problemsolving tasks such as device diagnosis and design. In this paper, we view problem solvers themselves as devices, and use structure-behavior-function models to represent how they work. The model representing the functioning of a problem solver explicitly specifies how the knowledge and reasoning of the problem solver result in the achievement of its goals. Then, we employ these models for performance-driven reflective learning. We view performance-driven learning as the task of redesigning the knowledge and reasoning of the problem solver to improve its performance. We use the model of the problem solver to monitor its reasoning. Assign blame when it fails, and appropriately redesign its knowledge and reasoning. This paper focuses on the model-based redesign of a path planner's task structure. It illustrates the modelbased reflection using examples from an operational system called the Autognostic system. 相似文献
10.
Associational reasoning solves common problems quickly. Model-based reasoning can be used to solve unfamiliar, unusual, or difficult problems, but it does so slowly. This paper describes a method for overcoming the speed limitations of model-based reasoning by remembering a previous similar problem and making small changes to its solution. The method described here was used to develop a medical diagnosis system. The method was shown to result in solutions identical to those derived by a model-based expert system for the same domain, but with an increase of several orders of magnitude in efficiency. Furthermore, the method used by the system is domain independent and should be applicable in other domains with models of a similar form. 相似文献
11.
针对采用传统方法解决动态系统的微分方程建模问题所遇到的困难和存在的不足,语文中设计了将遗传程序设计与遗传算法和相嵌套的混合演化建模算法,以遗传程序设计优化模型结构,以遗传算法优化模型参数,成功地实现了动态系统的常微分方程组建模过程自动化。 相似文献
12.
处理图象分析中的不确定性也是专家系统不可回避的任务.目前有多种用以表示不确定性,并能进行不精确推理的模型,主要有概率理论、证据理论和可能性理论;同时不精确推理的非数值方法也引起了人们的极大关注,如非单调逻辑.本文探讨了这些推理理论在一些具体图象分析问题中的应用途径. 相似文献
13.
Reforming socialist societies requires changes in values and beliefs in addition to institutions and skills. But changes in values should be brought about in a democratic fashion through conversation and the comparison of perceptions. A few quite simple methods exist for comparing conceptual systems and thereby focusing discussion on the cultural foundations of economic institutions. Once a cultural system is clearly defined, more sophisticated methods can be used to provide additional understanding. Devising appropriate actions to take as a result of these conversations is left to the individuals in these societies to decide. 相似文献
14.
Abstract Much knowledge residing in the knowledge base of an expert system involves fuzzy concepts. A powerful expert system must have the capability of fuzzy reasoning. This paper presents a new methodology for dealing with fuzzy reasoning based on the matching function S. The single-input, single-output (SISO) fuzzy reasoning scheme and the multi-input, single-output (MISO) fuzzy reasoning schemes are discussed in detail. The proposed fuzzy reasoning methodology is conceptually clearer than the compositional rule of inference approach. It can provide an useful way for rule-based systems to deal with fuzzy reasoning. 相似文献
15.
念代数CA是Nilsson教授以格(lattice)理论为数学背景提出的一个新的代数系统。在CA中,关系范型、OO范型、逻辑程序设计和框架知识表示获得了统一的表示-概念项,项进一步组成句子。一个完整的知识库就由这样折的项和句子组成。推理操作是一组被称为重写规则的代数公理。目前的CA还只是个代数系统雏形,有很多方面有待扩充。本文对概念代数进行综述,并给出初步的扩充。 相似文献
16.
The problem of detecting nontransient faults in sequential logic circuits by random testing was analyzed by Das et al. utilizing the well-known continuous parameter Markov model. Given a sequential circuit with certain stuck faults specified, the original state table and its error version can be readily derived from analysis of the circuit under fault-free and faulty conditions, respectively. By simulating these two tables next on a computer, we can obtain the parameters of the desired Markov model. For a specified confidence degree, it is easy to derive the parameters of the model and to calculate the required lengths of the random test patterns, or the maximum testing time. This paper presents further analysis of the model and reports simulation results on VAX 11/750 system which provides some useful insights into the nature of faults in relation to random testing and the associated confidence degree. 相似文献
17.
The last few years have seen the development of Discrete Event-Dynamic Net Systems 1,2 as instruments for modeling complex systems. They are able to achieve the following objectives: —formality of the modeling methodology —ability to model static and dynamic aspects —ability to pass between levels of differently rich structures by morphisms —uniform representation of the communication process as —an information process —a decision process and —a control process —homogeneity of the representation and modeling methods —ability to derive qualitative and quantitative statements. The foundation is provided by a Discrete Event-Dynamic Net System which includes the axiomatic declaration of general Petri nets. In order to calculate the structural and dynamic aspects, so-called Petri net machines are developed. It is shown that this approach can even be used to treat the following aspects: —use of time during the process —increase of costs during the generation and transportation of information —augmentation, evaluation and transformation of information objects. Recursive formulas are derived and some examples calculated. 相似文献
19.
We percept the infinitely various and diverse world as a huge system of systems. In the classification of them the one entity can be singled out and be called the growing systems. This paper presents an attempt of modeling such systems. It resulted with some non-trivial inferences and suggests methods of studying and controlling such systems. 相似文献
20.
Abstract A new procedure for construction of a fuzzy number is given, based on the covering of points by consequently contracting intervals. The approach leads to the membership function in the form of Devil's staircase, a borderline fractal finding many applications in the modern physics. The alternative definition of subsethood based on the self-similarity of the sets is also given. 相似文献
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