Abstract
This paper presents a framework to evaluate fieldbus; dependability in presence of transient faults. Several fault models, which copes most situations found in an industrial environment, are proposed. Fault impact on fieldbus communications is evaluated taking into account different communication protocols and specific operating modes. Bus redundancy and common-cause faults are also considered. Analytical models are proposed and closed-form expressions derived, enabling the identification of the most relevant parameters from a dependability viewpoint. Copyright (C) 2001 IFAC.

Abstract
Due to the complexity of underwater transients and background interference, model based approaches to transient detection/classification are often not practical. This has motivated an interest for data-driven, model-free methods. One such method was presented in [2] and modified in [1], where it was applied to the detection of underwater transients. In this article, we will extend that approach, to allow its use in the more demanding environment of a brown water environment, where background noise is constituted by a multitude of different interferences, non-white, and highly non-stationary. Also, the assumption of linear separability amongst the transients and the background noise in the time-frequency or related domains will be discarded, leading to the use of an additional classifier stage. A technique to minimize the number of prototypes on this classifier will be presented. The developed methods are used to detect and classify real underwater transients, recorded off the Portuguese coast. Estimation of the overall error rate of the method is obtained using cross-validation with the available data set, showing that these methods can effectively be used in real environment situations.

Abstract
Objective: The epilepsy associated with the hypothalamic hamartomas constitutes a syndrome with peculiar seizures, usually refractory to medical therapy, mild cognitive delay, behavioural problems and multifocal spike activity in the scalp electroencephalogram (EEG). The cortical origin of spikes has been widely assumed but not specifically demonstrated. Methods: We present results of a source analysis of interictal spikes from 4 patients (age 2-25 years) with epilepsy and hypothalamic hamartoma, using EEG scalp recordings (32 electrodes) and realistic boundary element models constructed from volumetric magnetic resonance imaging (MRIs). Multifocal spike activity was the most common finding, distributed mainly over the frontal and temporal lobes. A spike classification based on scalp topography was done and averaging within each class performed to improve the signal to noise ratio. Single moving dipole models were used, as well as the Rap-MUSIC algorithm. Results: All spikes with good signal to noise ratio were best explained by initial deep sources in the neighbourhood of the hamartoma, with late sources located in the cortex. Not a single patient could have his spike activity explained by a combination of cortical sources. Conclusions: Overall, the results demonstrate a consistent origin of spike activity in the subcortical region in the neighbourhood of the hamartoma, with late spread to cortical areas.

Abstract
View Synchrony (VS) is a powerful abstraction in the design and implementation of dependable distributed systems. By ensuring that processes deliver the same set of messages in each view, it allows them to maintain consistency across membership changes. However, experience indicates that it is hard to combine strong reliability guarantees as offered by VS with stable high performance. In this paper we propose a novel abstraction, Semantic View Synchrony (SVS), that exploits the application's semantics to cope with high throughput applications. This is achieved by allowing some messages to be dropped while still preserving consistency when new views are installed. Thus, SVS inherits the elegance of view synchronous communication. The paper describes how SVS can be implemented and illustrates its usefulness in the context of distributed multi-player games.

Abstract
P-3 is a next-generation Internet computing platform, building upon other experiments and implementing new ideas for high-performance parallel computing in the Internet environment. This paper describes its run-time system, programming model and how it compares to current state-of-the-art systems.

Abstract
Tabling or memoing is a technique where one stores intermediate answers to a problem so that they can be reused in further calls. Tabling is of interest to logic programming because it addresses some of the most significant weaknesses of Prolog. Namely, it can guarantee termination for programs with the bounded term-size property. Tabled programs exhibit a more complex execution mechanism than traditional Prolog's left-to-right search with backtracking. The reason is that Prolog programs are highly recursive and generate multiple answers. This rather involved execution mechanism requires a more complex implementation than traditional Prolog. The declarative nature of tabled logic programming suggests that it might be amenable to parallel execution. On the other hand, the complexity of the tabling mechanism, and the existence of a shared resource, the table, argues that parallelism might be limited, and that performance for real applications might never scale. In this work we prove that parallel tabling is indeed scalable for real applications by experimenting the OPTYap parallel tabled system on a scalable shared-memory machine. © 2002 IEEE.