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Object-oriented Databases (object-oriented + databases)

Distribution by Scientific Domains

Information Science and Computing	75%

Selected Abstracts

A set-oriented method definition language for object databases and its semantics

CONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 14 2003
Elisa Bertino
Abstract In this paper we propose a set-oriented rule-based method definition language for object-oriented databases. Most existing object-oriented database systems exploit a general-purpose imperative object-oriented programming language as the method definition language. Because methods are written in a general-purpose imperative language, it is difficult to analyze their properties and to optimize them. Optimization is important when dealing with a large amount of objects as in databases. We therefore believe that the use of an ad hoc, set-oriented language can offer some advantages, at least at the specification level. In particular, such a language can offer an appropriate framework to reason about method properties. In this paper, besides defining a set-oriented rule-based language for method definition, we formally define its semantics, addressing the problems of inconsistency and non-determinism in set-oriented updates. Moreover, we characterize some relevant properties of methods, such as conflicts among method specifications in sibling classes and behavioral refinement in subclasses. Copyright © 2003 John Wiley & Sons, Ltd. [source]

Virtual path signature: An approach for flexible searching in object-oriented databases

INTERNATIONAL JOURNAL OF INTELLIGENT SYSTEMS, Issue 1-2 2004
Pichayotai Mahatthanapiwat
Signature technique that is proposed for multikey indexing is used for flexible searching in the area of databases. In this article, we present a new signature technique called Virtual Path Signature for supporting query processing of aggregation hierarchy as a tree in object-oriented databases (OODBs). We derive cost formulas for its storage overhead as well as the retrieval cost. Comparing with the Tree Signature Scheme, the Virtual Path Signature shows significant improvement in the retrieval operation, especially when the target distance between the target class and the predicate class is high. © 2004 Wiley Periodicals, Inc. [source]

Features as an Abstraction for Designer Convenience in the Design of Ships

NAVAL ENGINEERS JOURNAL, Issue 4 2001
Joshua D. Summers
ABSTRACT This paper reports on a research effort involving design of a class of ships , nuclear submarines. It focuses on the use of features as a means of design abstraction, and it is found that a principal motivation for the use of features in this design environment is the convenience of the early stage submarine designer. To support this argument, a review of feature research is presented. Experiments in the development of feature catalogs are described, and implementation through two generations of feature-based submarine CAD systems are discussed. The architecture of the feature-based submarine CAD systems includes the use of Microsoft Foundation Classes (MFC), the ACIS geometric modeler, and user interfaces which store/recall hierarchical submarine feature information easily. Strong connections to object-oriented programming and object-oriented databases are recognized. Conclusions are drawn regarding the use of features for ship designer convenience and regarding support provided by hierarchical, parameterized features for other means of design automation. [source]