Abstract

Abstract

Abstract
Communication networks are in continuous progress with the aim of providing a wider variety of services to satisfy the demands of large numbers of very different users. With increasingly complex systems and increasingly competitive markets, software developers face a difficult challenge: how to create services more quickly, at lower cost, that will be of top-level quality and may be improved easily. Based on two tools, our goal was to expedite the creation of distributed services, by translating the files generated in a formal specification environment (GEODE), at the moment a service is specified, into files supported by a distributed architecture (ANSA), for subsequent implementation. In this paper, a description of the most important concepts of the two software packages is given and an implementation for the intended translation is presented.

Abstract
An efficient algorithm for dynamically multiplexing MPEG2 encoded video sources is presented. Sources are grouped into classes regarding different combined levels of spatial detail and amount of movement. Simulations were performed using different associations of sources belonging to distinct classes, different bit rates and GOP structures. The implications associated to a real implementation are analyzed and a modular architecture is proposed. Simulation results are presented and discussed, showing that sequences with higher spatial detail and motion are those which exhibit the higher quality improvements. These results are almost not affected by the non alignment, at GOP level, between video sequences.

Abstract
An investigation is performed of the characteristics of the self-referencing intensity based Q-type fibre optic sensor using a recirculation loop structure. Both transmissive and reflective configurations are analysed. Via the definition of the measurement parameter (the R parameter) the linearity and sensitivity of the sensor are addressed. Theoretical and experimental results are compared, considering the problem of sensor design and optimization. © 1995 Taylor & Francis Ltd.

Abstract
The phasor visualizer presented in this paper is performs real time calculation in steady-state and transient conditions of simultaneous electromagnetic torque, magnetic flux, voltages and currents of an induction motor supplied with sinusoidal voltages or through frequency converters and provide an oscillographic display. The phasor visualizer is an instrument for analysis, investigations and teaching of AC machine drives. The instruments needs no shaft position or speed sensor, it uses exclusively the acquired stator currents and voltages. The main fields of application are: element of a monitoring system, integration in a control unit, research tool for induction motor drives, and test shop. Practical results of the implementation are be presented and discussed.