Abstract

Abstract
This paper describes a genetic algorithm approach to the optimal multistage planning of distribution networks. The authors describe a mathematical and algorithmic model that they have developed and experimented with success. The paper also presents application examples, with real size systems. The advantages of adopting this new approach are discussed in the planning context, namely in conjunction with the adoption of multicriteria decision making methods.

Abstract
By adopting theories as primitive components of a logic and recognizing that formulae are just presentation details we arrive at the concept of topological institution. In a topological institution, we have, for each signature, a frame of theories, a set of interpretation structures and a satisfaction relation. More precisely, we have, for each signature, a topological system. We show how to extract a topological institution from a given institution and establish an adjunction. Illustrations are given within the context of equational logic. We study the compositionality of theories. Formulae are recovered when we establish a general technique for presenting topological institutions. Topological institutions with finitely observable theories are shown to be useful in temporal monitoring applications where we would like to be able to characterize the properties of the system that can be monitored. Namely, an invariant property (Gf) cannot be monitored because it cannot be positively established in finite time. On the contrary, a reactivity property (Ff) can be positively established in finite time. © Springer-Vedag Berlin Heidelberg 1995.

Abstract
In this paper, we are interested in the study and analysis of how activities are executed at the lowest level of the manufacturing networks hierarchy. At this level, a Real-Time Distributed Database (RTDD) provides a logical link between local applications. The role of the Fieldbus network is to link local sites enabling their interactions and preserving RTDD temporal and spatial consistency. Specific characteristics of Fieldbus supported RTDDs, such as a `deterministic transaction subset', allow us to introduce the `network transparency' concept, which is the basis of a proposed overall system development. An [Iso, SC5] based model is presented, providing an efficient method to describe the network transparency concept into standardized description techniques.

Abstract
This paper presents some properties which must be verified by the project of distributed application in order to make good use of fieldbuses. In general, application and network projects are developed by different persons, such that a good interaction must be reached. With the aim of doing that, Concurrent Engineering have been more and more used. A specification methodology (Internal Behavioral and Conceptual Configuration Models) of real-time distributed application is presented, based on both Concurrent Engineering and Network Transparency Concept, which offers all necessary information to the network project.

Abstract
An effective scheduling policy known as the Dynamic Cycle Lengths Heuristic was introduced by Leachman and Gascon in 1988 for the multi-item, single-machine production system facing stochastic, time-varying demands. In this article we develop a heuristic scheduling policy for the multi-machine extension of the same problem. We integrate the concepts of the Dynamic Cycle Lengths Heuristic with a nonlinear integer optimization model to obtain an overall scheduling policy that allocates items to machines and schedules production quantities during the next time period. We report promising performance in limited simulation tests of the policy.