Treatment of imprecise probabilities within the probabilistic satis®ability approach to uncertainty in knowledge-based systems is surveyed and discussed. Both probability intervals and qualitative probabilities are considered. Analytical and numerical methods to test coherence and bound the probability of a conclusion are reviewed. They use polyhedral combinatorics and advanced methods of linea...

We tackle the problem of finding a smallest-cardinality MUS (SMUS) of a given formula. The SMUS provides a succinct explanation of infeasibility and is valuable for applications that rely on such explanations. We present a branch-and-bound algorithm that utilizes iterative MAXSAT solutions to generate lower and upper bounds on the size of the SMUS, and branch on specific subformulas to find it....

Argumentation concepts have been applied to numerous knowledge engineering endeavours in recent years. For example, a variety of logics have been developed to represent argumentation in the context of a dialectical situation such as a dialogue. In contrast to the dialectical approach, argumentation has also been used to structure knowledge. This can be seen as a non-dialectical approach. The To...

CAMES (computer-aided mechanical expert system) is a tool for automatically designing material-handling equipment used in pulp and paper mills. Operational since 1988, it has designed over 700 machines in a total of 5 classes and, consequently, has influenced our principles for deploying all knowledge-based systems. Because it is being extended to other machines within our group of companies, i...

This paper presents the TASK framework which is intended to cover the life cycle of a Knowledge-Based System. TASK provides (i) a conceptual language which enable an informal specification at the knowledge level, (ii) a formal language TFL which permits an unambiguous specification and (iii) an operational shell TASK+ which allows an efficient execution even for bad structured problems. This pa...

In the current economy, individual firms cannot possess all the knowledge that is necessary to compete. Hence, networking relationships become an important way through which firms can develop their potential by accessing to resources of other players. However, the networking strategies that companies implement can vary depending on the nature of their competitive conditions and on their specifi...

We present a case study of reusing the same problemsolving method for the related tasks of temporal abstraction and linear-space abstraction. The method, known as knowledge-based temporal abstraction, abstracts high-level concepts from time-stamped raw data, and was evaluated primarily in clinical domains. We applied this method to the domain of traffic control, in which the monitoring task req...

This paper will introduce, compare and contrast two prototype knowledge systems as it presents a more general framework for thinking about how community of practice and organizational perspectives to knowledge management might be integrated. The first prototype is called the Knowledge Nebula Crystallizer (KNC). The KNC is a demonstration of concept developed at the University of Tokyo. It is us...