Two operational approaches to belief revision are presented in this paper. The rules of Rcalculus are modified in order to deduce all the maximal consistent subsets. Another set of rules is given in order to deduce all the minimal inconsistent subsets. Then a procedure, which can generate all the maximal consistent subsets, is presented. They are complete approaches, since all the maximal consistent subsets can be deduced or generated. In this paper, only the case of propositional logic is considered.

Multidimensional aggregation is a dominant operation on data ware-houses for on-line analytical processing (OLAP). Many efficient algorithms to compute multidimensional aggregation on relational database based data warehouseshave been developed. However, to our knowledge, there is nothing to date in theliterature about aggregation algorithms on multidimensional data warehouses thatstore datasets in multidimensional arrays rather than in tables. This paper presentsa set of multidimensional aggregation algori…

According to the soundness and completeness of information in databases, the expressive form and the semantics of incomplete information are discussed in this paper. On the basis of the discussion, the current studies on incomplete data in relational databases are reviewed. In order to represent stochastic uncertainty in most general sense in the real world, probabilistic data are introduced into relational databases. An extended relational data model is presented to express and manipulate probabilistic dat…

Semistructured data are specified in lack of any fixed and rigidschema, even though typically some implicit structure appears in the data. Thehuge amounts of on-line applications make it important and imperative to mine theschema of semistructured data, both for the users (e.g., to gather useful informationand facilitate querying) and for the systems (e.g., to optimize access). The criticalproblem is to discover the hidden structure in the semistructured data. Currentmethods in extracting Web data structure…

In this paper, the authors present the design and implementation of an Interoperable Object Platform for Multi-Databases (IOPMD). The aim of the system is to provide a uniform object view and a set of tools for object manipu lation and query based on heterogeneous multiple data sources under client/server environment. The common object model is compatible with ODMG2.0 and OMG'sCORBA, which provides main OO features such as OID, attribute, method, inheri tance, reference, etc. Three types of interfaCes, name…

This paper defines a new kind of rule, probability functional dependency rule. The functional dependency degree can be depicted by this kind of rule. Five algorithms, from the simple to the complex, are presefited to mine this kind of rule in different condition. The related theorems are proved to ensure the high efficiency and the correctness of the above algorithms.

Two inference rules are discussed in boolean ring based theorem proving, and linear strategy is developed. It is shown that both of them are complete for linear strategy. Moreover, by introducing a partial ordering on atoms, pseudo O-linear and O-linear strategies are presented. The former is complete, the latter,however, is complete for clausal theorem proving.

This paper proposed a novel text representation and matching scheme for Chinese text retrieval. At present, the indexing methods of Chinese retrieval systems are either character-based or word-based. The character-based indexing methods, such as bi-gram or tri-gram indexing, have high false drops due to the mismatches between queries and documents. On the other hand, it's difficult to efficiently identify all the proper nouns, terminology of different domains, and phrases in the word-based indexing systems....

Up to now, there have been many methods for knowledge representation and reasoning in causal networks, but few of them include the research on the coactions of nodes. In practice, ignoring these coactions may influence the accuracy of reasoning and even give rise to incorrect reasoning. In this paper, based on multilayer causal networks, the definitions on coaction nodes are given to construct a new causal network called Coaction Causal Network, which serves to construct a model of neural network for diagno…

The intersection of N half Planes is a basic problem in computational geometry and computer graphics. The optimal offiine algorithm for this problem runs in time O(N log N). ln this paper, an optimal online algorithm which runs also in time O(N log N) for this problem is presented. The main idea of the algorithm is to give a new definition for the left side of a given line, to assign the order for the points of a convex polygon, and then to use binary search method in an ordered vertex set.The data structur…

As the web grows, the massive increase in information is placing severe burdens on information retrieval and sharing. Automated search engines and directories with small editorial staff are unable to keep up with the increasing submission of web sites. To address the problem, this paper presents Infomarker an Internet information service system based on open Directory and Zero-Keywond Inquiry. The oPen Directory sets up a net-community in which the increasing netcitizens can each organize a small portion of…