Abstract
Line scratches and blotches are two of the most common and annoying artifacts of image sequences. A digital restoration chain for the removal of these artifacts was conceived and implemented. The basic elements of the chain are the digital encoder, the artifact generator, tile artifact detectors, the interpolators and the quality measurer. The digital encoder has the mission to convert analogue sequences into digital ones and, if necessary, to make a format conversion. The artifact generator allows quantitative and qualitative tests of the restoration algorithms. If we have access to the original non-degraded sequence we can add, in a controlled way, artifacts with the generator, and then measure efficiently the quality of the restoration algorithms, since we have the original, the degraded and the restored sequences to compare. In a real restoration process, the degraded sequence is directly applied to the artifact detector. The artifact detector finds the degraded regions in tile image and, somehow, marks them. Tile interpolator replaces the marked degraded pixels with others that are the result of an interpolation algorithm. Finally, the quality measurer rates the quality of the restored sequence.

Abstract
In this paper we address the real-time capabilities of P-NET, which is a multi-master fieldbus standard based on a virtual token passing scheme. We show how P-NETS medium access control (MAC) protocol is able to guarantee a bounded access time to message requests. We then propose a model for implementing fixed priority-based dispatching mechanisms at each master's application level. in this way, we diminish the impact of the first-come-first-served (FCFS) policy that P-NET uses at the data link layer. The proposed model rises several issues well known within the real-time systems community message release jitter; pre-run-time schedulability analysis in non pre-emptive contexts; non-independence of tasks at the application level. We identify these issues in the proposed model and show how results available for priority-based task dispatching can be adapted to encompass priority-based message dispatching in P-NET networks.

Abstract

Abstract
This paper provides a comprehensive study on how to use Profibus fieldbus networks to support real-time industrial communications, that is, on how to ensure the transmission of real-time messages within a maximum bound time, Profibus is based on a simplified timed token (TT) protocol, which is a well-proved solution for real-time communication systems. However, Profibus differs with respect to the TT protocol, thus preventing the application of the usual TT protocol real-time analysis. In fact, real-time solutions for networks based on the TT protocol rely on the possibility of allocating specific bandwidth for the real-time traffic. This means that a minimum amount of time is always available, at each token visit, to transmit real-time messages, Conversely, with the Profibus protocol, in the worst case, only one real-time message is processed per token visit. We propose two approaches to guarantee the real-time behavior of the Profibus protocol: 1) an unconstrained low-priority traffic profile and 2) a constrained low-priority traffic profile. The proposed analysis will show that the first profile is a suitable approach for more responsive systems (tighter deadlines), while the second allows for increased nonreal-time traffic throughput.

Abstract
Economic operation of medium-sized and large isolated power systems with a high penetration of renewables, namely wind power, is not well suited neither by the conventional unit commitment/dispatch arrangements for interconnected systems, nor by the simplified procedures used in small systems. In this paper, the economic scheduling functions developed within CARE are described. The main idea is to perform on-line unit commitment in the same cycle with the dispatch, using the most recent forecasts, as described by Hatziargyriou et al. (2000). The Unit Commitment module has two variants: one based on Genetic Algorithms, and one using a Combinatorial Approach. On the other hand, three alternative procedures were developed for the Economic Dispatch: a Linear Programming Optimal Power Flow, an Evolutionary approach and a Genetic Algorithms based procedure. The paper describes the main features of the five approaches, including test results when appropriate.Economic operation of medium-sized and large isolated power systems with a high penetration of renewables, namely wind power, is not well suited neither by the conventional unit commitment/dispatch arrangements for interconnected systems, nor by the simplified procedures used in small systems. In this paper, the economic scheduling functions developed within CARE are described. The main idea is to perform on-line unit commitment in the same cycle with the dispatch, using the most recent forecasts, as described by Hatziargyriou et al. (2000). The Unit Commitment module has two variants: one based on Genetic Algorithms, and one using a Combinatorial Approach. On the other hand, three alternative procedures were developed for the Economic Dispatch: a Linear Programming Optimal Power Flow, an Evolutionary approach and a Genetic Algorithms based procedure. The paper describes the main features of the five approaches, including test results when appropriate.

Abstract
A recent trend in distributed computer-controlled systems (DCCS) is to interconnect the distributed computing elements by means of multi-point broadcast networks. Since the network medium is shared between a number of network nodes, access contention exists and must be solved by a medium access control (MAC) protocol. Usually, DCCS impose real-time constraints. In essence, by real-time constraints we mean that traffic must be sent and received within a bounded interval, otherwise a timing fault is said to occur. This motivates the use of communication networks with a MAC protocol that guarantees bounded access and response times to message requests, PROFIBUS is a communication network in which the MAC protocol is based on a simplified version of the timed-token protocol. In this paper we address the cycle time properties of the PROFIBUS MAC protocol, since the knowledge of these properties is of paramount importance for guaranteeing the real-time behaviour of a distributed computer-controlled system which is supported by this type of network.