Jacky Akoka

Entity-relationship and object-oriented model automatic clustering

Automatic clustering of semantic models allows a multilevel abstraction of the same reality and reduces design complexity. This paper is concerned with the development and application of automatic clustering of Entity-Relationship (E-R) diagrams and object models. This paper does not consider physical clustering which aims at improving performance of databases but deals with conceptual clustering whose objective is to facilitate the understanding of the database schema. We provide an automatization of conceptual schema clustering leading to a unification of past approaches. Automatization is achieved through the definition of semantic distances between concepts and the use of a clustering algorithm. For entity-relationship clustering, we define three different distances (visual, hierarchical and cohesive) depending on the semantic richness. Object model clustering is based on structural, semantic and communication characteristics of objects. Our approach has been implemented and applied to a great number of examples, leading to interesting results. Applications of automatic clustering in several areas and their potential as a communication, documentation and design tools for E-R diagrams and object oriented models are described and discussed.

Framework For Automatic Clustering of Semantic Models

This article is concerned with the development, application and implication of automatic clustering of Entity-Relationship (E-R) diagrams and object models, called here semantic models. The development of such technique is discussed with particular reference to those areas where clustering of semantic models may assist progress in aiding the understanding of an organizations data. Topics such as the role of a new clustering algorithm, how best to represent distances between the elements of the model to be clustered, and the organizational context in which this clustering technique is deployed are addressed. Applications of automatic clustering in several areas and their potential as a communication, documentation and design tools for ER diagrams and object oriented models are described and discussed.

Logistics information system auditing using expert system technology

Abstract This paper brings together two methodological strands of thinking. These are the managerial problem solving methodology of Logistics Information System auditing and the structured development of expert system technology. The investment being made in logistics in organizations is enormous and, although much effort has been devoted to creating structured methods to aid the development of information systems to support these organizations logistics, the area of Logistics Information System auditing remains less developed. The major aim of this paper is to provide a systemic approach of the application of expert system technology to Logistics Information System auditing. Taking a strategic view of Management Information System (MIS) in logistics, this paper describes the application of INFAUDITOR, an audit expert system, to logistics information systems auditing. INFAUDITOR has two fundamental features. First, it covers all domains of information systems, managerial (like logistics) as well as technical aspects. Secondly, it helps to determine, in a given audit situation, the respective importance that should be given to the different audit domains and tests of control. INFAUDITOR can be viewed as consisting of several expert systems as in blackboard systems. Its fact bases include the characteristics of the enterprise, its logistics information system and the audit objectives. Its rule bases encompass the audit criteria represented as a hierarchical tree. INFAUDITOR is used to assess the ability of a Logistics Information System (LIS) to provide decision makers with relevant, timely information for designing, planning and maintaining an efficient production system, for securing materials necessary for production, and for facilitating achievement of low operating and maintenance costs. We present and discuss results obtained by using INFAUDITOR in auditing the logistics Management Information System of a large European company.