Normalization in object-oriented design is much different from that in relational database design. Not only are the conceptual data model of objectoriented (o-o) models integrating m’cher structuring capabilities than that of relational models, but also the dependency constraints, attribute ranges and access paths in o-o models are more complex than that in relational models. In o-o models, inh...

We propose a two-layered model for computing semantic and conceptual interpretations from dependency structures. Abstract interpretation schemata generate semantic interpretations of `minimal' dependency subgraphs, while production rules whose speci cation is rooted in ontological categories derive a canonical conceptual interpretation from semantic interpretation structures. Con gurational des...

This paper presents an enhancement to ontology formalization, combining previous work in Conceptual Structure Theory and Order-Sorted Logic. In particular, the relation type hierarchy of the former theory is a subset of the predicate hierarchy of the latter. Most existing ontology formalisms place greater importance on concept types, but this paper focuses more on relation types, which are in e...

(extended abstract) Thomas A. Mueck Martin L. Polaschek Abteilung f ur Data Engineering Universitat Wien fmueck, [email protected] Abstract Multikey index structures for type hierarchies are a recent alternative to traditional B+-tree based proposals. A prerequisite for the e cient use of multikey structures in this eld is an appropriate linearization of the type hierarchy. We prese...

The hierarchical structure of a knowledge base system can lead to various valuable applications; however, many knowledge base systems do not have such property. In this paper, we propose an entity-driven approach to automatically construct the hierarchical structure of entities for knowledge base systems. By deriving type dependencies from entity information, the initial graph of types will be ...

We present a software tool for creating an optimal classhierarchy from the use-relationship among data-items and functions based on the method in Kundu and Gwee [3]. The tool determines the classes and their inheritance relationship, including the assignment of variables and functions to the various classes and their appropriate access levels (private, etc.). We define a class-design language f...

This paper presents an inheritanceJow model, which represents the inheritance relationships among classes as a flow graph. A flow operation is associated with each attribute and method in a class to denote the defined (redefined) or inherited member. An inherited member can be deemed as being handled by a sequence of flow operations along a path in the flow graph. This model provides several an...

We show analogues of a theorem due to Valiant and Vazirani [16] for intractable parameterized complexity classes such as W[P], W[SAT] and the classes of the W-hierarchy as well as those of the A-hierarchy. We do so by proving a general “logical” version of it which may be of independent interest.