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{Summary: We first consider a class of consistent semi-parametric estimators of a positive tail index $\gamma$, parametrised in a tuning or control parameter $\alpha$. Such a control parameter enables us to have access for any available sample, to an estimator of the tail index $\gamma$ with a null dominant component of asymptotic bias and consequently with a reasonably flat mean squared error pattern, as a function of $k$, the number of top-order statistics considered.\par Such a control parameter depends on a second-order parameter $\rho$, which will be adequately estimated so that we may achieve a high efficiency relative to the classical Hill estimator [ıt B. M. Hill}, Ann. Stat. 3, 1163–1174 (1975; Zbl 0323.62033)] provided we use a number of top-order statistics larger than the one usually required for the estimation through the Hill estimator. An illustration of the behaviour of the estimators is provided, through the analysis of the daily log-returns on the Euro-US\$ exchange rates.}

The main aim of the Valomat project was the development of new materials for quarry back-filling and underground constructions, based on the reuse of bottom ashes from MSWI. Bottom ashes were collected in six incineration plants of Europe. Some of them were selected for the development of new materials.
One task of this project comprised the study of the long-term behavior of new materials, under simulated conditions of environmental exposure. Three different scenarios were studied. For each scenario, a pilot plant was constructed and the new materials were studied under laboratory conditions or natural weather. The long-term behavior of these materials was assessed through the characterization of chemical and ecotoxicological properties of the leachates.
The chemical contamination and the ecotoxicological levels of the leachates were relatively low, although different levels had been determined for the three different scenarios. The immersion in dechlorinated tap water (scenario S1) had shown the highest emission levels of chlorides, sulphates, DOC, and Al, especially for the materials B2/1 and B2/2. The lowest ecotoxicological and chemical levels were determined in the scenario in which the materials were buried in a sieved soil.

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In the last decade a considerable amount of research work has focused on distributed debugging, one of the crucial fields in the parallel software development cycle. The productivity of the software development process strongly depends on the adequate definition of what debugging tools should be provided, and what debugging methodologies and functionalities should these tools support. The work described in this dissertation was initiated in 1995, in the context of two research projects, the SEPP (Software Engineering for Parallel Processing) and HPCTI (High-Performance Computing Tools for Industry), both sponsored by the European Union in the Copernicus program, which aimed at the design and implementation of an integrated parallel software development environment. In the context of these projects, two independent toolsets have been developed, the GRADE and EDPEPPS parallel software development environments. Our contribution to these projects was in the debugging support. We have designed a debugging engine and developed a prototype, which was integrated the both toolsets (it was the only tool developed in the context of the SEPP and HPCTI projects which achieved such a result). Even after the closing of those research projects, further research work on distributed debugger has been carried on, which conducted to the re-design and re-implementation of the debugging engine. This dissertation describes the debugging engine according to its most up-to-date design and implementation stages. It also reposts some of the experimental work made with both the initial and the current implementations, and how it contributed to validate the design and implementations of the debugging engine.

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The introduction of new courses on virtual organizations at the engineering education level is an important element for the broad acceptance of this new paradigm. This article summarizes the experience with an initiative of teaching Virtual Enterprises / Virtual Organizations subjects to Electrical and Computer Engineering students. The course structure, both in its lecture and lab work components, is described. Finally, some lessons learned with two editions of this course are presented.

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