infonet-economy

This report defines synchronised Petri nets with inhibitor arcs and an extension of these nets that integrates real-time constraints. The semantics of these nets is given by a transition system built using Structured Operational Semantics (SOS) rules. This report is part of a larger framework that attempts to attach real-time constraints to the CO-OPN/2 language.

Designing and building a Web site aimed to interact with a database can be a demanding task. A way to accelerate this task is to use a declarative language for specifying hypertext views on databases. In this paper, we discuss hypertext concepts for viewing and acting on a database. While viewing a database through a hypertext view enables a user to navigate among interconnected...

This paper presents first a formal development methodology that enables the validation of formal specifications as well as program codes wrt client's requirements. The methodology is based on the two languages framework: it advocates the joint use of a model-oriented specification and a logical language. Second, the paper describes development guidelines for system design within...

The ever increasing need for education combined with the recent advances in communication technologies, have encouraged the introduction of numerous remote learning systems and services. In this paper we describe a distance learning system we have developed at the University of Geneva. We also describe the experience we have gained by using the system for conducting telelectures...

This paper presents a comparative survey of formalisms related to mobile agents. It describes the π-calculus and its extensions, the Ambient calculus, Petri nets, Actors, and the family of generative communication languages. Each of these formalisms defines a mathematical framework that can be used to reason about mobile code; they vary greatly in their expressiveness, in the...

The Java object oriented programming language has been the subject of an important involvement from programmers and the industry. Especially for applications related to the Web. The problem of such a rapid penetration of Java programs into commercial products is that software engineers do not have any methodology and have to develop complex parallel applications. We present a formal...

A Coordianted Atomic Action (CA Action) is a unified scheme for coordinating complex concurrent activities and supporting error recovery between multiple interacting objects in distributed object-oriented systems. They constitute a very interesting concept for the structured developement of fault-tolerant distributed applications. To formalize the design of CA actions, this paper...

The objective of this paper are twofold. On the one hand, it sims to show the advantages of Co-ordinated Atomic actions (CA actions) as a design concept for dependable distributed system development, and on the other hand, it explains how the formal language CO-OPN/2 can be used to express the semantics of CA action design. A fault-tolerant distributed application is developed...

The messenger paradigm is one of the earliest models which propose the exchange of code to implement computer communication. Code becomes mobile and mobile code is now considered a promising alternative for the implementation of distributed applications. One application of mobile code is in the implementation of software agents which themselves are used to implement complex...