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Continuous case-based reasoning   总被引:6,自引:0,他引:6  
Case-based reasoning systems have traditionally been used to perform high-level reasoning in problem domains that can be adequately described using discrete, symbolic representations. However, many real-world problem domains, such as autonomous robotic navigation, are better characterized using continuous representations. Such problem domains also require continuous performance, such as on-line sensorimotor interaction with the environment, and continuous adaptation and learning during the performance task. This article introduces a new method for continuous case-based reasoning, and discusses its application to the dynamic selection, modification, and acquisition of robot behaviors in an autonomous navigation system, SINS (self-improving navigation system). The computer program and the underlying method are systematically evaluated through statistical analysis of results from several empirical studies. The article concludes with a general discussion of case-based reasoning issues addressed by this research.  相似文献   

3.
We describe a decision-theoretic methodology for case-based reasoning in diagnosis and troubleshooting applications. The system utilizes a special-structure Bayesian network to represent diagnostic cases, with nodes representing issues, causes, and symptoms. Dirichlet distributions are assessed at knowledge acquisition time to indicate the strength of relationships between variables. During a diagnosis session, a relevant subnetwork is extracted from a Bayesian-network database that describes a very large number of diagnostic interactions and cases. The constructed network is used to make recommendations regarding possible repairs and additional observations, based on an estimate of expected repair costs. As cases are resolved, observations of issues, causes, symptoms, and the success of repairs are recorded. New variables are added to the database, and the probabilities associated with variables already in the database are updated. In this way, the inferential behavior of system adjusts to the characteristics of the target population of users. We show how these elements work together in a cycle of troubleshooting tasks, and describe some results from a pilot system implementation and deployment  相似文献   

4.
Alain   《Annual Reviews in Control》2006,30(2):223-232
CBR is an original AI paradigm based on the adaptation of solutions of past problems in order to solve new similar problems. Hence, a case is a problem with its solution and cases are stored in a case library. The reasoning process follows a cycle that facilitates “learning” from new solved cases. This approach can be also viewed as a lazy learning method when applied for task classification. CBR is applied for various tasks as design, planning, diagnosis, information retrieval, etc. The paper is the occasion to go a step further in reusing past unstructured experience, by considering traces of computer use as experience knowledge containers for situation based problem solving.  相似文献   

5.
Introspective reasoning can enable a reasoner to learn by refining its own reasoning processes. In order to perform this learning, the system must monitor the course of its reasoning to detect learning opportunities and then apply appropriate learning strategies. This article describes lessons learned from research on a computer model of how introspective reasoning can guide failure-driven learning. The computer model monitors its own reasoning by comparing it to a model of the desired behaviour of its reasoning, and learns in response to deviations from the ideal defined by the model. The approach is applied to the problem of determining indices for selecting cases from a case-based planner's memory. Experiments show that learning driven by this introspective reasoning both decreases retrieval effort and improves the quality of plans retrieved, increasing the overall performance of the planning system compared to case learning alone.  相似文献   

6.
This paper presents four synergistic systems that exemplify the approaches and benefits of case-based reasoning in medical domains. It then explores how these systems couple Artificial Intelligence (AI) research with medical research and practice, integrate multiple AI and computing methodologies, leverage small numbers of available cases, reason with time series data, and integrate numeric data with contextual and subjective information. The following systems are presented: (1) CARE-PARTNER, which supports the long-term follow-up care of stem-cell transplantation patients; (2) the 4 Diabetes Support System, which aids in managing patients with type 1 diabetes on insulin pump therapy; (3) Retrieval of HEmodialysis in NEphrological Disorders, which supports hemodialysis treatment of patients with end stage renal disease; and (4) the Mälardalen Stress System, which aids in the diagnosis and treatment of stress-related disorders.  相似文献   

7.
An introduction to case-based reasoning   总被引:33,自引:0,他引:33  
Case-based reasoning means using old experiences to understand and solve new problems. In case-based reasoning, a reasoner remembers a previous situation similar to the current one and uses that to solve the new problem. Case-based reasoning can mean adapting old solutions to meet new demands; using old cases to explain new situations; using old cases to critique new solutions; or reasoning from precedents to interpret a new situation (much like lawyers do) or create an equitable solution to a new problem (much like labor mediators do). This paper discusses the processes involved in case-based reasoning and the tasks for which case-based reasoning is useful.This article is excerpted from Case-Based Reasoning by Janet Kolodner, to be published by Morgan-Kaufmann Publishers, Inc. in 1992.This work was partially funded by darpa under Contract No. F49620-88-C-0058 monitored by AFOSR, by NSF under Grant No. IST-8608362, and by ARI under Contract No. MDA-903-86-C-173.  相似文献   

8.
在智能决策系统(IDSS)获取知识的推理体系中,案例推理和规则推理有着各自的优点,而混合两者的集成推理可以克服两者的缺点,提高系统的效率和综合推理能力。但是集成推理系统缺乏通用性,延长了开发周期,且不利于规则库和案例库的重用。一种可扩充的集成推理框架为了解决上面的问题而被提出,该框架利用智能决策支持语言Knonit的组件性,对不同的集成方式可方便地扩充相应的集成推理方案,从而快速地搭建IDSS应用;同时规则和案例是作为Knonit广义知识元存在,可以在集成推理框架中复用,另一方面,Knonit的动态特性和可扩充性也对案例库和知识库动态的调整和扩充提供了支持。  相似文献   

9.
Scenario-based knowledge representation in case-based reasoning systems   总被引:4,自引:0,他引:4  
Bo Sun  Li Da  Xu  Xuemin Pei  Huaizu Li 《Expert Systems》2003,20(2):92-99
A scenario-based representation model for cases in the domain of managerial decision-making is proposed. The scenarios in narrative texts are converted to scenario units of knowledge organization. The elements and structure of the scenario unit are defined. The scenario units can be linked together or coupled with others. Compared with traditional case representation methods based on database tables or frames, the proposed model is able to represent knowledge in the domain of managerial decision-making at a much deeper level and provide much more support for case-based systems employed in business decision-making.  相似文献   

10.
基于事例推理中差异驱动的事例修改策略研究   总被引:3,自引:0,他引:3  
张光前  邓贵仕 《计算机应用》2005,25(7):1658-1660
总结CBR已有的事例修改的理论和方法,以知识的观点重新看待事例修改问题,从而找到了事例修改的难点,并在此基础上提出了在CBR体系结构上加入知识库,用来存储事例修改的规则;采用差异驱动的事例修改策略获得事例修改规则并进行事例修改。不仅充分利用了已有的CBR流程和事例,并对采用特征和特征值表示的事例具有普遍的意义。  相似文献   

11.
An exercise in formalising teleological case-based reasoning   总被引:2,自引:2,他引:0  
This paper takes up Berman and Hafner's (1993) challenge to model legal case-based reasoning not just in terms of factual similarities and differences but also in terms of the values that are at stake. The formal framework of Prakken and Sartor (1998) is applied to examples of case-based reasoning involving values, and a method for formalising such examples is proposed. The method makes it possible to express that a case should be decided in a certain way because that advances certain values. The method also supports the comparison of conflicting precedents in terms of values, and it supports debates on the relevance of distinctions in terms of values.  相似文献   

12.
基于实例推理系统中的权重分析   总被引:6,自引:0,他引:6  
艾芳菊 《计算机应用》2005,25(5):1022-1025
指标权重的确定在基于实例推理(CBR)系统的检索模型中起着重要的作用。采用基于多位专家的二级模糊综合评判方法求得各个指标的总的综合权重,对指标权重进行了讨论,并引入关联度的概念,讨论了各专家的偏离度及一致性。实例证明有效、可行。  相似文献   

13.
《Knowledge》2002,15(5-6):293-300
In applications of interactive case-based reasoning (CBR) such as help-desk support and recommender systems, a problem that often affects retrieval performance is the inability to distinguish between cases that have different solutions. For example, it is not unusual in recommender systems for two distinct products or services to have the same values for all attributes in the case library. While it is unlikely that both solutions are equally suited to the user's requirements, the system cannot help the user to choose between them. This problem, which we refer to as inseparability, can also arise as a result of incomplete data in the target problem presented for solution by a CBR system. We present an in-depth analysis of the inseparability problem, its relationship to the problem of incomplete data, and its impact on retrieval performance.  相似文献   

14.
Case-Based Reasoning (CBR) can be seen as a problem-solving paradigm that advocates the use of previous experiences to limit search spaces and to reduce opportunities for error repetition. In this paradigm, the case at hand is compared against former experiences to select from a set of possible courses of action the best one. A comparison method is required to ensure that the most resembling experience is, in fact, chosen to drive the problem-solving process. This paper discusses an object-oriented framework that provides a scale-guided measure of similarity between objects, and shows how this framework can be applied for case-based reasoning, drawing examples from device diagnosis.  相似文献   

15.
16.
In this paper, we present an indexing technique for case-based reasoning called D-HSE, that is shown to be more competent than and twice as efficient as the commonly used R-tree. D-HSE was designed to addresses periodical competency shortcomings of the related D-HSM index but unfortunately in doing so some efficiency was seen to be sacrificed. In order to address this problem of competency verses efficiency, we propose an intelligent selection algorithm that automatically analyses the case-base and decides which index (D-HSM or D-HSE) should be used to optimize performance. The algorithm is designed to favour competency at the expense of efficiency where a competency gain is deemed highly likely to be achieved by using the less efficient approach. In effect we are proposing a flexible indexing scheme that is aware of changes within its environment and which reacts to these changes to optimize performance.  相似文献   

17.
Inspection planning is discussed in a framework where a rich choice of instruments is available and robots can also participate in the inspection process. The problem of constrained plan optimization is exposed, and a solution is suggested that is based on task grouping. After outlining the overall planning process, we give details of the optimization stage where case-based reasoning is applied. Finally, it will be shown how the implemented knowledge-based system can operate as a knowledge server.  相似文献   

18.
This paper shows that case-based reasoning (CBR), an artificial intelligence technique, is a quite efficient tool in monitoring financial market against its possible collapse. For this purpose, daily financial condition indicator (DFCI) monitoring financial market is built on CBR and its performance is compared to DFCI on neural network. This study is empirically done for the Korean financial market.  相似文献   

19.
Case based reasoning (CBR) is an artificial intelligence technique that emphasises the role of past experience during future problem solving. New problems are solved by retrieving and adapting the solutions to similar problems, solutions that have been stored and indexed for future reuse as cases in a case-base. The power of CBR is severely curtailed if problem solving is limited to the retrieval and adaptation of a single case, so most CBR systems dealing with complex problem solving tasks have to use multiple cases. The paper describes and evaluates the technique of hierarchical case based reasoning, which allows complex problems to be solved by reusing multiple cases at various levels of abstraction. The technique is described in the context of Deja Vu, a CBR system aimed at automating plant-control software design  相似文献   

20.
Launched in 2003, Second Life is a computer-based pseudo-environment accessed via the Internet. Although a number of individuals and companies have developed a presence (lands) in Second Life, there is no appropriate methodology in place for undertaking such developments. While some existing methods have been adapted by users to their individual needs, this paper explores the development of a method for developing lands specifically within Second Life. This method is based on case-based reasoning (CBR) as this method has a number of similarities with Second Life itself. A system was designed based on CBR with some modifications to work in accordance with Second Life. In this paper, the system and its modifications are discussed and its application to the development of space within Second Life is evaluated. From tracking its progress against previous specifications and future activity, an updated version of the CBR web tool component covering the latest changes and improvements in the tool is introduced here.  相似文献   

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