Cookies
O website necessita de alguns cookies e outros recursos semelhantes para funcionar. Caso o permita, o INESC TEC irá utilizar cookies para recolher dados sobre as suas visitas, contribuindo, assim, para estatísticas agregadas que permitem melhorar o nosso serviço. Ver mais
Aceitar Rejeitar
  • Menu
Publicações

1998

Parallel and distributed processing in state estimation of power system energy

Autores
Carvalho, JB; Barbosa, FM;

Publicação
MELECON '98 - 9TH MEDITERRANEAN ELECTROTECHNICAL CONFERENCE, VOLS 1 AND 2

Abstract
The fast development in electrical power networks and his consequent complexity, impose a more useful state estimation operational scheme, shortening the time interval between consecutive state estimations. Technical developments in distributed Energy Management Systems (EMS), based on fast data communication networks, open up the possibility of Parallel and Distributed State Estimation implementation. In this paper will be introduced and discussed some ideas for the implementation of Parallel ana Distributed State Estimation in electrical power systems. Will be boarding a solution methodology based on conventional state estimation algorithms applicable in local networks and will be analysed some results obtained with a IEEE test system so that we can appreciate the performances of the proposed method. An evaluation of the degree of natural decoupling in the state estimation problem is also performed, and will be compared with the results of computational experiments with standard WLS methods, in the integral and distributed version.

1998

Guaranteeing real-time message deadlines in PROFIBUS networks

Autores
Tovar, E; Vasques, F;

Publicação
10TH EUROMICRO WORKSHOP ON REAL-TIME SYSTEMS, PROCEEDINGS

Abstract
This paper provides a comprehensive study on how to use Profibus networks to support real-time communications, that is, ensuring the transmission of the real-time messages before their deadlines. Profibus is based on a simplified Timed Token (TT) protocol, which is a well-proved solution for real-time communication systems. However, Profibus differences to the TT protocol prevent the application of the usual TT analysis. The main reason is that, conversely to the TT protocol, in the worst case, only one high-priority message is processed per token visit. The major contribution of this paper is to prove that, despite this shortcoming, it is possible to guarantee communication real-time behaviour with the Profibus protocol.

1998

A parallel algorithm to power systems state estimation

Autores
Carvalho, JB; Barbosa, FM;

Publicação
POWERCON '98: 1998 INTERNATIONAL CONFERENCE ON POWER SYSTEM TECHNOLOGY - PROCEEDINGS, VOLS 1 AND 2

Abstract
In this paper we develop a theoretically robust and computationally efficient state estimator algorithm, to solve the WLS problem by using parallel processing. Technical developments in distributed Energy Management Systems (EMS), based on fast data communication networks, open up the possibility of Parallel Processing in the state estimation algorithms. We have analysed the computational aspects of the parallel processing. Moreover, we have simulated this state estimator parallel algorithm in the IEEE 30, 57 and 118 bus systems. The numerical accuracy of the simulation demonstrates the excellent computational performance of the parallel algorithm. Results of computational experiments are compared with standard WLS methods, in the integral and distributed version. An evaluation of the degree of natural decoupling in the state estimation problem is also performed. The results of computational experiments indicate that a distributed processing for state estimation, is the better way to adopt the parallel computing in power systems energy.

1998

A video coder using 3-D model based background for video surveillance applications

Autores
Martins, I; Corte Real, L;

Publicação
1998 INTERNATIONAL CONFERENCE ON IMAGE PROCESSING - PROCEEDINGS, VOL 2

Abstract
In this paper we present a model based video coder for remote video surveillance applications at very low bit rates. Unlike the known model based video codecs, we use the model based approach for background modeling and not for "head-and-shoulders" modeling. Since in video surveillance the remote site that is being monitored is usually a previously known physically closed space, we build a 3-D model of the site and use it to synthesize the background of the scene for each of the video cameras used. The codec has two layers, one layer for the background using a 3-D model and a second layer for the part of the scene not represented by the background. The second layer may use conventional hybrid DPCM-DCT coding schemes, like H.263, or object-based coding techniques, like those used in MPEG-4 video VM. The proposed codec can be a good framework for a multiview codec.

1998

Lrc - A generator for incremental language-oriented tools

Autores
Kuiper, M; Saraiva, J;

Publicação
COMPILER CONSTRUCTION

Abstract

1998

Distance: A New Metric for Controlling Granularity for Parallel Execution

Autores
Shen, K; Costa, VS; King, A;

Publicação
Proceedings of the 1998 Joint International Conference and Symposium on Logic Programming, Manchester, UK, June 15-19, 1998

Abstract

  • 4460
  • 4544