To achieve a certain degree of confidence that a given program follows its specification, a testing phase must be included in the program development process, and also a complementary debugging phase to help locating the program's bugs. This paper presents an environment which results of the composition and integration of two basic tools: STEPS (Structural TEsting of Parallel Software), which is a testing tool, and DDBG (Distributed DeBuGger), which is a debugging tool. The two tools are presented individually as stand-alone tools, and we describe how they were combined through the use of another intermediate tool: DEIPA (Deterministic re-Execution and Interactive Program Analysis). We claim that the result achieved is a very effective testing and debugging environment.

We report the three-dimensional crystal structure of acidic seminal fluid protein (aSFP), a 12.9 kDa poly-peptide of the spermadhesin family isolated from bovine seminal plasma, solved by the multiple isomorphous replacement method and refined with data to 1.9 Angstrom resolution with a final R-factor of 17.3%. aSFP is built by a single CUB domain architecture, a 100 to 110 amino-acid-residue extracellular module found in 16 functionally diverse proteins. The structure of aSFP reveals that the CUB domain displays a beta-sandwich topology organised into two 5-stranded beta-sheets, each of which contain two parallel and four antiparallel strands. The structure of aSFP is almost identical to that of porcine spermadhesins PSP-I and PSP-II, which in turn show limited structural similarity with jellyroll topologies of certain virus capsid proteins. Essentially, topologically conserved residues in these proteins are those internal amino acids forming the hydrophobic core of the CUB and the jellyroll domains, suggesting their importance in maintaining the integrity of these protein folds, On the other hand, the structure of aSFP shows structural features that are unique to this protein and which may provide a structural ground for understanding the distinct biological properties of different members of the spermadhesin protein family. (C) 1997 Academic Press Limited.

Spermadhesins, 12,000-14,000 M-r mammalian proteins, include lectins involved in sperm-egg binding and display a single CUB domain architecture. We report the crystal structures of porcine seminal plasma PSP-I/PSP-II, a heterodimer of two glycosylated spermadhesins. and bovine aSFP at 2.4 Angstrom and 1.9 Angstrom resolution respectively.

{Bovine acidic seminal fluid protein (aSFP) is a 12.9 kDa polypeptide of the spermadhesin family built by a single CUB domain architecture. The CUB domain is an extracellular module present in 16 functionally diverse proteins. To determine the three-dimensional structure of aSFP, the protein was crystallized at 21 degrees C by vapor diffusion in hanging drops, using ammonium sulfate, pH 4.7, and polyethyleneglycol 4000 as precipitants, containing 10% dioxane to avoid the formation of clustered crystals. Elongated prismatic crystals with maximal size of 0.6 x 0.3 x 0.2 mm(3) diffract to beyond 1.9 Angstrom resolution and belong to space group P2(1)2(1)2, with cell parameters a = 52.4 Angstrom

To achieve a certain degree of confidence that a given program follows its specification, a testing phase must be included in the program development process, and also a complementary debugging phase to help locating the program’s bugs. This paper presents an environment which results of the composition and integration of two basic tools: STEPS (Structural TEsting of Parallel Software), which is a testing tool, and DDBG (Distributed DeBuGger), which is a debugging tool. The two tools are presented individually as stand-alone tools, and we describe how they were combined through the use of another intermediate tool: DEIPA (Deterministic re-Execution and Interactive Program Analysis). We claim that the result achieved is a very effective testing and debugging environment.

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We consider singular integral operators with piecewise continuous coefficients on reflexive Orlicz spaces \(L_M(\Gamma)\), which are generalizations of the Lebesgue spaces \(L_p(\Gamma)\), \(1 < p < \infty\). We suppose that \(\Gamma\) belongs to a large class of Carleson curves, including curves with corners and cusps as well as curves that look locally like two logarithmic spirals scrolling up at the same point. For the singular integral operator associated with the Riemann boundary value problem with a piecewise continuous coefficient \(G\), we establish a Fredholm criterion and an index formula in terms of the essential range of \(G\) complemented by spiralic horns depending on the Boyd indices of \(L_M(\Gamma)\) and contour properties. Our main result is a symbol calculus for the closed algebra of singular integral operators with piecewise continuous matrix-valued coefficients on \(L_M^n(\Gamma)\).

This paper presents an approach to education in Parallel and Distributed Processing undertaken in the Technical University of Gdansk and Technical University of Wroclaw. The paper gives a detailed structure of the project entitled "Teaching Parallel Processing: Development of Curriculum and Software Tools" which was started in 1994 and will be finish in 1997. Two universities from Poland: Technical University of Gdansk and Technical University of Wroclaw and two universities from EC countries: University Autònoma of Barcelona from Spain and University Nova of Lisbon from Portugal participate in the presented project. The main aim of the project is to develop existing curricula of Computer Science specialisation and to establish specialisation concerned with parallel and distributed processing at Polish universities.

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The present communication analyses the relationships between work organisation and quality systems. The analysis is based on results from a study funded by the "Specific Programme for the Development of Portuguese Industry" (PEDIP). The main issues which have been currently associated with work organisation and quality control in the Portuguese industry are characterized. Critical features related to the implementation of quality systems and new methods of work organisation for industrial development are also discussed. A few recommendations are given in order to promote appropriate methods of work organisation for quality improvement within Portuguese industry.

In this paper it is analysed the relationships between work organisation and quality systems in firms that uses some forms of advanced automation. Are characterised the existing quality control structures in the Portuguese industry, and the main factors that hidden or fosters the development of sociotechnical methods of quality control organisation strategies. Are analysed some industrial cases that explains more clearly the critical issues of the implementation of quality systems and work organisation systems. A few recommendations are given about the possibilities for the development of new forms of work organisation and the quality systems associated to automated manufacturing systems.

This paper analyses the problems and trends of the introduction of anthropocentric production systems (APS) in small less industrialized member states of the European Union, specifically the case of Portugal, based on the report for the FAST-Anthropocentric Technology Assessment Project (Monitor Programme) on “Prospects and conditions for APS in Europe by the 21st century”. Research teams from all countries of the European Community, as well as researchers from USA, Japan and Australia were participating in this project. The aim of this paper is to characterize APS and to present some special considerations related to the socioeconomic factors affecting the prospects and conditions for APS in Portugal. APS is defined as a system based on the utilization of skilled human resources and flexible technology adapted to the needs of flexible and participative organization. Among socioeconomic factors, some critical aspects for the development of APS will be focused, namely technological infrastructure, management strategies, perceived impact of introduction of automated systems on the division of labor and organizational structure, educational and vocational training and social actors strategies towards industrial automation. This analysis is based on a sample of industrial firms, built up for qualitative analysis, and on case studies analysis that can be reference examples for further development of APS, and not just for economic policy purposes alone. We have also analyzed the type of existing industrial relations, the union and employer strategies and some aspects of public policies towards the introduction of new technologies in the order to understand the extent to which there exist obstacles to and favorable conditions for the diffusion of anthropocentric systems. Finally some recommendations are presented to stress the trends for the implementation and development of anthropocentric production systems in Portugal.

A study on negative ion formation in the scattering of a proton beam from two monolayers of Ba on Ag( 111) surface is pre- sented. The dependence of the negative ion yield on the polar scattering angle and azimuthal orientation of the crystal has been determined for beam energies from 500 to 1000 eV. In addition the yield of fast neutrals has been determined. Based upon a shadowing and blocking analysis of the angular distributions of the H- ions, it can be concluded that the Ba overlayer shows the same crystalline structure as the Ag( 111) substrate. The recorded negative ion fractions can be explained by a simple model describing resonant charge transfer calculated by the non-perturbative CAM method and taking into account the parallel velocity effect.

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VEEM93A13

The DC analysis of a series-resonant converter operating above resonant frequency is presented. The results are used to analyze the current form factor and its effect on the efficiency. The selection of the switching frequency to maximize the efficiency is considered. The derived expressions are generalized and can be applied to calculations in any of the switching modes for a series-resonant circuit. For switching frequencies higher than the resonant frequency, an area of more efficient operation is indicated which will aid in the design of this class of converters and power supplies. It is pointed out that (especially for power MOSFETs where ohmic losses dominate) it is more attractive to select switching frequencies that are higher than the resonant frequency because of the possibility of nondissipative snubbers. Slowing down the rise of the gate voltage and, hence, the slow decrease of ON resistance during turn-on is also not a drawback to high-frequency switching. Because of this safer operation, the standard intrinsic diode of the power MOSFET could be used at high frequencies instead of the more expensive FREDFET

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