In this paper, we propose a new security enforcement mechanism and demonstrate how this mechanism can enforce policies for both mandatory access control (MAC) and discretionary access control (DAC) in an object database system. Each class may have a security method that can block messages that leave instances of the class, and can block messages directed to instances of the class. Each supercla...

The evolution of object-oriented databases (OODBs) has not been accompanied by an equivalent evolution of theoretical models, leaving the foundations for OODBs ill-defined. Design of OODBs has been hampered by the lack of design techniques/tools which correspond to the theoretical model. This paper defines a core conceptual object oriented database (COODB) model providing a foundation and frame...

We present an idea of using mathematicall modelling to guide a process of mining a set of patterns in an RDF graph and further exploiting these patterns to build expressive OWL class hierarchies.

Object-oriented programming is considered in the context of software communities – groups of designers and developers sharing knowledge and experience. One way of fostering reuse of this experience is by establishing large collections of reusable object classes. Resulting problems include: Class packaging and class organization – how can classes and their methods be represented to simplify reus...

We give machine characterizations of most parameterized complexity classes, in particular, of W[P], of the classes of the W-hierarchy, and of the A-hierarchy. For example, we characterize W[P] as the class of all parameterized problems decidable by a nondeterministic fixed-parameter tractable algorithm whose number of nondeterministic steps is bounded in terms of the parameter. The machine char...

We describe a method for analysing the temporal structure of a discourse which takes into account the eeects of tense, aspect, temporal adverbials and rhetorical structure and which minimises unnecessary ambiguity in the temporal structure. It is part of a discourse grammar implemented in Carpenter's ale formalism. The method for building up the temporal structure of the discourse combines cons...

Luo’s Extended Calculus of donstructions (ECC) is a higher order functional calculus based on Coquand’s and Huet’s Calculus of Constructions, but has in addition strong sums and a predicative cumulative type hierarchy. In this paper I introduce inductive types on the predicative type levels of ECC. I also show how the o-Set model for ECC can be extended to a model for this augmented calculus. '...

This paperpresents the DT Framework, a collection of object-oriented classes representing a generalized framework for inheritance management and table-based method dispatch. It demonstrates how most existing table-based dispatch techniques can be generalized and made incremental, so that relevant entries in the dispatch table are modified each time a selector or class hierarchy link is added or...

This paper presents a modeling approach which couples fuzzy object-oriented database modeling with fuzzy logic. The modeling approach introduced here handles fuzziness at attribute, object/class and class/superclass levels in addition to fuzziness in class/class relationships and various associations among classes. We utilize logical rules to define some of the crisp/fuzzy relationships and ass...

Inheritance conflicts in class hierarchies are avoidable through design that considers application semantics. An algorithm, in the form of IFTHEN statements, is presented that resolves any name conflicts in class hierarchies. Several examples are given which show that conflicts arise because of poor design. These conflicts can be resolved by redesigning the schema, renaming properties, redefini...