Most of expert systems use the text-oriented knowledge bases. However, knowledge management using the knowledge bases is considered as a huge burden to the knowledge workers because it includes some troublesome works. It includes chasing and/or checking activities on Consistency, Redundancy, Circulation, and Refinement of the knowledge. In those cases, we consider that they could reduce the bur...

Security features must be addressed when escalating a distributed database. The choice between the object oriented and the relational data model, several factors should be considered. The most important of these factors are single and multilevel access controls (MAC), protection and integrity maintenance. While determining which distributed database replica will be more secure for a particular ...

This paper describes our experience with using Grid files as the main storage organization for a relational database management system. We primarily focus on the following two aspects. (i) Strategies for implementing grid files efficiently. (ii) Methods for efficiency evaluating queries posed to a database organized using grid files.

The Starburst project, at IBM’s Almaden Research Center, is improving the design of relational database management systems and enhancing their performance, while building an extensible system to better support nontraditional applications (such as engineering, geographic, office, etc.), and to serve as a testbed for future improvements in database technology. As of November 1989, we have an init...

With the data volume that does not stop growing and the multitude of sources that led to diversity of structures, data processing needs are changing. Although, relational DBMSs remain the main data management technology for processing structured data, but faced with the massive growth in the volume of data, despite their evolution, relational databases, which have been proven for over 40 years,...

This paper argues that a lexical database should be implemented with a special kind of database management system (DBMS) and outlines the design of such a system. The major difference between this proposal and a general purpose DBMS is that its data definition language (DDL) allows the specification of the entire morphology, which turns the lexical database from a mere collection of 'static' da...

The structure of data to be stored by a Data Base Management System (DBMS) is usually decided by a database administrator. Individual users and applications are generally interested in only a subset of the data stored in the database. Often, they wish to see this subset structured in a way which reflects their particular needs. Since it is not generally possible to structure a database so as to...

This paper presents a novel approach for medical image storage using a Fuzzy Object-Relational Database Management System (FORDBMS). The system stores medical images along with a set of parameters describing their content. Flexible queries can be performed over these parameters to retrieve images matching visually. To illustrate the capabilities of the FORDBMS, parameter curves are obtained fro...

In a multilevel secure database management system (MLSDBMS). users cleared at different security levels access and share a database consisting of data at different sensitivity levels. A powerful and dynamic approach to assigning sensitivity levels (also called security levels) to data is one which utilizes security constraints or classification rules. Security constraints provide an effective a...

Researches concerning Temporal Databases are being developed for more than 20 years. However, very few implemented systems are available. Several temporal data models were proposed, extending traditional data models in a way to capture also the temporal features. A feasible way of implementing a Temporal Database is using a conventional commercial database mapping the temporal data model to it....