6,668 research outputs found

    A requirements engineering and management training course for software development professionals

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    Devising a course for software professionals working in industry depends on several factors. In order to create a course that fulfils professionals’ expectations, it is important to take account of the skills of the participants, the time available, and the specific topics to be covered. This paper presents the curriculum of a course in requirements engineering and management intended for software developers with a first-level academic degree in computing and experience in developing real software solutions. This context requires the course to concentrate on topics that were not taught in the participants’ previous education and that can have a positive impact on their daily practices

    Piecewise smooth systems near a co-dimension 2 discontinuity manifold: can one say what should happen?

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    We consider a piecewise smooth system in the neighborhood of a co-dimension 2 discontinuity manifold Σ\Sigma. Within the class of Filippov solutions, if Σ\Sigma is attractive, one should expect solution trajectories to slide on Σ\Sigma. It is well known, however, that the classical Filippov convexification methodology is ambiguous on Σ\Sigma. The situation is further complicated by the possibility that, regardless of how sliding on Σ\Sigma is taking place, during sliding motion a trajectory encounters so-called generic first order exit points, where Σ\Sigma ceases to be attractive. In this work, we attempt to understand what behavior one should expect of a solution trajectory near Σ\Sigma when Σ\Sigma is attractive, what to expect when Σ\Sigma ceases to be attractive (at least, at generic exit points), and finally we also contrast and compare the behavior of some regularizations proposed in the literature. Through analysis and experiments we will confirm some known facts, and provide some important insight: (i) when Σ\Sigma is attractive, a solution trajectory indeed does remain near Σ\Sigma, viz. sliding on Σ\Sigma is an appropriate idealization (of course, in general, one cannot predict which sliding vector field should be selected); (ii) when Σ\Sigma loses attractivity (at first order exit conditions), a typical solution trajectory leaves a neighborhood of Σ\Sigma; (iii) there is no obvious way to regularize the system so that the regularized trajectory will remain near Σ\Sigma as long as Σ\Sigma is attractive, and so that it will be leaving (a neighborhood of) Σ\Sigma when Σ\Sigma looses attractivity. We reach the above conclusions by considering exclusively the given piecewise smooth system, without superimposing any assumption on what kind of dynamics near Σ\Sigma (or sliding motion on Σ\Sigma) should have been taking place.Comment: 19 figure

    The evolution of interdisciplinarity in physics research

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    Science, being a social enterprise, is subject to fragmentation into groups that focus on specialized areas or topics. Often new advances occur through cross-fertilization of ideas between sub-fields that otherwise have little overlap as they study dissimilar phenomena using different techniques. Thus to explore the nature and dynamics of scientific progress one needs to consider the large-scale organization and interactions between different subject areas. Here, we study the relationships between the sub-fields of Physics using the Physics and Astronomy Classification Scheme (PACS) codes employed for self-categorization of articles published over the past 25 years (1985-2009). We observe a clear trend towards increasing interactions between the different sub-fields. The network of sub-fields also exhibits core-periphery organization, the nucleus being dominated by Condensed Matter and General Physics. However, over time Interdisciplinary Physics is steadily increasing its share in the network core, reflecting a shift in the overall trend of Physics research.Comment: Published version, 10 pages, 8 figures + Supplementary Informatio

    The Swiss Board Directors Network in 2009

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    We study the networks formed by the directors of the most important Swiss boards and the boards themselves for the year 2009. The networks are obtained by projection from the original bipartite graph. We highlight a number of important statistical features of those networks such as degree distribution, weight distribution, and several centrality measures as well as their interrelationships. While similar statistics were already known for other board systems, and are comparable here, we have extended the study with a careful investigation of director and board centrality, a k-core analysis, and a simulation of the speed of information propagation and its relationships with the topological aspects of the network such as clustering and link weight and betweenness. The overall picture that emerges is one in which the topological structure of the Swiss board and director networks has evolved in such a way that special actors and links between actors play a fundamental role in the flow of information among distant parts of the network. This is shown in particular by the centrality measures and by the simulation of a simple epidemic process on the directors network.Comment: Submitted to The European Physical Journal

    How should we measure psychological resilience in sport performers?

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    Psychological resilience is important in sport because athletes must constantly withstand a wide range of pressures to attain and sustain high performance. To advance psychologists’ understanding of this area, there exists an urgent need to develop a sport-specific measure of resilience. The purpose of this paper is to review psychometric issues in resilience research and to discuss the implications for sport psychology. Drawing on the wider general psychology literature to inform the discussion, the narrative is divided into three main sections relating to resilience and its assessment: adversity, positive adaptation, and protective factors. The first section reviews the different ways that adversity has been measured and considers the potential problems of using items with varying degrees of controllability and risk. The second section discusses the different approaches to assessing positive adaptation and examines the issue of circularity pervasive in resilience research. The final section explores the various issues related to the assessment of protective factors drawing directly from current measures of resilience in other psychology sub-disciplines. The commentary concludes with key recommendations for sport psychology researchers seeking to develop a measure of psychological resilience in athletes

    Worldwide food recall patterns over an eleven month period: A country perspective.

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    <p>Abstract</p> <p>Background</p> <p>Following the World Health Organization Forum in November 2007, the Beijing Declaration recognized the importance of food safety along with the rights of all individuals to a safe and adequate diet. The aim of this study is to retrospectively analyze the patterns in food alert and recall by countries to identify the principal hazard generators and gatekeepers of food safety in the eleven months leading up to the Declaration.</p> <p>Methods</p> <p>The food recall data set was collected by the Laboratory of the Government Chemist (LGC, UK) over the period from January to November 2007. Statistics were computed with the focus reporting patterns by the 117 countries. The complexity of the recorded interrelations was depicted as a network constructed from structural properties contained in the data. The analysed network properties included degrees, weighted degrees, modularity and <it>k</it>-core decomposition. Network analyses of the reports, based on 'country making report' (<it>detector</it>) and 'country reported on' (<it>transgressor</it>), revealed that the network is organized around a dominant core.</p> <p>Results</p> <p>Ten countries were reported for sixty per cent of all faulty products marketed, with the top 5 countries having received between 100 to 281 reports. Further analysis of the dominant core revealed that out of the top five transgressors three made no reports (in the order China > Turkey > Iran). The top ten detectors account for three quarters of reports with three > 300 (Italy: 406, Germany: 340, United Kingdom: 322).</p> <p>Conclusion</p> <p>Of the 117 countries studied, the vast majority of food reports are made by 10 countries, with EU countries predominating. The majority of the faulty foodstuffs originate in ten countries with four major producers making no reports. This pattern is very distant from that proposed by the Beijing Declaration which urges all countries to take responsibility for the provision of safe and adequate diets for their nationals.</p
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