1,109 research outputs found

    Synchronous development in open-source projects: A higher-level perspective

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    Mailing lists are a major communication channel for supporting developer coordina tion in open-source software projects. In a recent study, researchers explored tempo ral relationships (e.g., synchronization) between developer activities on source code and on the mailing list, relying on simple heuristics of developer collaboration (e.g., co-editing fles) and developer communication (e.g., sending e-mails to the mailing list). We propose two methods for studying synchronization between collaboration and communication activities from a higher-level perspective, which captures the complex activities and views of developers more precisely than the rather technical perspective of previous work. On the one hand, we explore developer collaboration at the level of features (not fles), which are higher-level concepts of the domain and not mere technical artifacts. On the other hand, we lift the view of developer com munication from a message-based model, which treats each e-mail individually, to a conversation-based model, which is semantically richer due to grouping e-mails that represent conceptually related discussions. By means of an empirical study, we investigate whether the diferent abstraction levels afect the observed relationship between commit activity and e-mail communication using state-of-the-art time series analysis. For this purpose, we analyze a combined history of 40 years of data for three highly active and widely deployed open-source projects: QEMU, BusyBox, and OpenSSL. Overall, we found evidence that a higher-level view on the coordina tion of developers leads to identifying a stronger statistical dependence between the technical activities of developers than a less abstract and rather technical view

    An adjusted analytical solution for thermal design in artificial ground freezing

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    Artificial ground freezing is a widely used, reliable method for excavation in water-bearing ground. The questions posed in the thermal design of ground freezing projects require solving moving boundary (Stefan) problems. Approximate analytical solutions, such as the ones by St¨ ander1 and Sanger and Sayles,2 have been developed for thermal engineering design and are used by practitioners across the industry. For instance, Sanger & Sayles’ solution is widely used for the single-freeze-pipe problem, but it has proven to be of limited accuracy.3 In the present paper, an adjustment to this formula is proposed based on the re-evaluation of their empirical assumption that the ratio between the temperature penetration depth and the phase-change radius equals a constant value of 3 regardless the conditions. A sensitivity study is performed using a verified numerical model as a benchmark to study several problems with different initial and boundary conditions (initial, phase change and freeze pipe temperatures) and thermal properties of the ground (water content, thermal conductivity and heat capacity). This is done for the freezing times of 10 and 365 days, in order to consider the potential change of the ratio with the freezing time. In this way, a calibrated formula is proposed to find appropriate values of this ratio and a suitable adjustment to Sanger & Sayles’ solution is determined. Adjusting Sanger & Sayles’ solution in this manner, a significantly higher and more consistent accuracy is achieved for different boundary and initial conditions. This accuracy improvement was checked for real conditions from an engineering project, which shows that the adjustment can be useful for thermal problems in engineering design of ground freezing

    An humanoid robot for inspections and cleaning tasks in nuclear glove box

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    This article presents an opportunity evaluation of the use of humanoid robots in a nuclear environment. The project worked on the DaRwIn-OP platform to assess and carry out the modifications the robot needed to enable it to perform as an intervention operator in a nuclear location. The study had two main lines, based on equipping the humanoid with a radiological measurement capture system and with an arm command system using a depth camera. The tests performed showed the robot's ability to make radiological measurements with the built in detector and to collect swipe samples to assess the contamination of an object

    Robot humanoïde d'inspection et d'assainissement en boite gants nucléaire

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    Ce travail présente une évaluation de l'opportu-nité d'utiliser des robots humanoïdes en milieu nucléaire. Ce projet a utilisé la plateforme du DaRwIn-OP pour lui apporter les modifications nécessaires afin d'en faire un opérateur d'intervention en milieu nucléaire. Les deux axes de travail ont consisté à équiper l'humanoïde d'un capteur de mesure radiologique et d'une commande des bras par une caméra en champ profond. Les tests réalisés montrent la capacité de réaliser des mesures radiologiques au moyen du capteur intégré et la réalisation de frottis pour évaluer la contamination d'un objet

    TrustNShare Partizipativ entwickeltes, Smart-contract basiertes Datentreuhandmodell mit skalierbarem Vertrauen und Inzentivierung

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    Überblick über die Ziele, Projektpartner (DLR, UKB, UKJ) und Aufgabenbereiche des Projekts "TrusNShare". Fokus liegt auf der Erläuterung des geplanten Treuhandmodells, der Partizipativen Entwicklung möglicher Anreize und der "Healthy Navigation App"

    Contextual influences on physical activity and eating habits -options for action on the community level

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    Background: This conceptual paper aims to illustrate the ways in which communities are able to advance health improvements on a population level. Outcome measures may include increased physical activity and healthier eating habits in particular, as well as an improved health-related quality of life and social cohesion as more generic outcomes. Main body: The paper begins by asking initial questions: Why did previous health-specific interventions only show moderate effects on an individual level and mixed effects on a population level? What is the added value of a community-based public health perspective compared to the traditional biomedical perspective when it comes to prevention? Why are we living the way we are living? Why do we eat what we eat? Why do we move the way we move? Subsequently, we illustrate the broad spectrum of contextual interventions available to communities. These can have geographical and technological as well as economic, political, normative and attitude-specific dimensions. It is shown that communities have a strong influence on health-related contexts and decision-making of adults, adolescents and children. In addition contextual characteristics, effects, mediators, moderators and consequences relevant for health can differ greatly between age groups. Both small-scale settings and overarching sectors possess physical, economic, political and sociocultural characteristics that can be proactively influenced by community decision-makers in the sense of a “health in all policies”-strategy. Short conclusion: After presenting various interdisciplinary approaches to community-based health interventions, the manuscript closes with the following core message: Successful community-based health promotion strategies consist of multilevel – multicomponent interventions on the micro, meso and macro-level-environments

    Sprachliche Verfestigung und sprachlich Verfestigtes.: Einleitung

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    The present special issue of Linguistik Online is dedicated to theoretical and methodological approaches to formulaic language use from a pragmatic perspective. Following the assumption that language use is thoroughly shaped by routines and prefabricated patterns, formulaic language plays a central role in recent theoretical and empirical approaches to language use like construction grammar or corpus pragmatics. Within the field of phraseology, pragmatic approaches have become prevalent, too, be it by corpus linguistic foundations or by a functional perspective on phrasemes in different communicative domains. Based on case studies from various fields like language acquisition, cultural linguistics or colonial studies, the papers of this special issue discuss the role of formulaicity on the different levels of language use. They demonstrate which concepts and empirical methods are suitable to capture the pragmatic aspects of formulaic language use
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