30,261 research outputs found

    A Study of Concurrency Bugs and Advanced Development Support for Actor-based Programs

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    The actor model is an attractive foundation for developing concurrent applications because actors are isolated concurrent entities that communicate through asynchronous messages and do not share state. Thereby, they avoid concurrency bugs such as data races, but are not immune to concurrency bugs in general. This study taxonomizes concurrency bugs in actor-based programs reported in literature. Furthermore, it analyzes the bugs to identify the patterns causing them as well as their observable behavior. Based on this taxonomy, we further analyze the literature and find that current approaches to static analysis and testing focus on communication deadlocks and message protocol violations. However, they do not provide solutions to identify livelocks and behavioral deadlocks. The insights obtained in this study can be used to improve debugging support for actor-based programs with new debugging techniques to identify the root cause of complex concurrency bugs.Comment: - Submitted for review - Removed section 6 "Research Roadmap for Debuggers", its content was summarized in the Future Work section - Added references for section 1, section 3, section 4.3 and section 5.1 - Updated citation

    Value Framing: A Prelude to Software Problem Framing

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    Software problem framing is a way to find specifications for software. Software problem frames can be used to structure the environment of a software system (the machine) and specify desired software properties in such a way that we can show that software with these properties will help achieve the required effects in the environment. Actually framing a software problem, i.e. finding suitable problem frames of a given situation, is creative activity for which no guidelines are currently known. In this paper, we propose to use an idea exploration technique called e3-value to find software problem frames. The e3-value methodology is an approach to help business analysists solve the problem of designing a networked enterprise, defined as a set of businesses or business units that make money by performing value exchanges over a computer network. The outcome of e3-value is viewed by business managers as a solution, but it is a problem for software engineers who have to implement this idea. In this paper we illustrate the combination of e3-value with problem framing by means of a small example from real life, and discuss the research questions that come out of this

    Moving Targets: Instruction with iPads

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    This contributed paper details a project involving the creation of a mobile instruction ‘classroom in a box’, which consisted of twelve iPads, a laptop and a charging cart. What went well, what was changed, some recommendations, and how the tablets have been most commonly used, in a competitive exposure to library resources called Library Rally in the first year Communication and English classes, are covered

    Cherenkov Telescope Array Data Management

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    Very High Energy gamma-ray astronomy with the Cherenkov Telescope Array (CTA) is evolving towards the model of a public observatory. Handling, processing and archiving the large amount of data generated by the CTA instruments and delivering scientific products are some of the challenges in designing the CTA Data Management. The participation of scientists from within CTA Consortium and from the greater worldwide scientific community necessitates a sophisticated scientific analysis system capable of providing unified and efficient user access to data, software and computing resources. Data Management is designed to respond to three main issues: (i) the treatment and flow of data from remote telescopes; (ii) "big-data" archiving and processing; (iii) and open data access. In this communication the overall technical design of the CTA Data Management, current major developments and prototypes are presented.Comment: 8 pages, 2 figures, In Proceedings of the 34th International Cosmic Ray Conference (ICRC2015), The Hague, The Netherlands. All CTA contributions at arXiv:1508.0589

    Replicability, real-time data, and the science of economic research: FRED, ALFRED, and VDC

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    This article discusses the linkages between two recent themes in economic research: "real time" data and replication. These two themes share many of the same ideas, specifically, that scientific research itself has a time dimension. In research using real-time data, this time dimension is the date on which particular observations, or pieces of data, became available. In work with replication, it is the date on which a study (and its results) became available to other researchers and/or was published. Recognition of both dimensions of scientific research is important. A project at the Federal Reserve Bank of St. Louis to place large amounts of historical data on the Internet holds promise to unify these two themes.Research ; Federal Reserve Bank of St. Louis

    Special Libraries, September 1970

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    Volume 61, Issue 7https://scholarworks.sjsu.edu/sla_sl_1970/1006/thumbnail.jp

    Open semantic service networks

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    Online service marketplaces will soon be part of the economy to scale the provision of specialized multi-party services through automation and standardization. Current research, such as the *-USDL service description language family, is already defining the basic building blocks to model the next generation of business services. Nonetheless, the developments being made do not target to interconnect services via service relationships. Without the concept of relationship, marketplaces will be seen as mere functional silos containing service descriptions. Yet, in real economies, all services are related and connected. Therefore, to address this gap we introduce the concept of open semantic service network (OSSN), concerned with the establishment of rich relationships between services. These networks will provide valuable knowledge on the global service economy, which can be exploited for many socio-economic and scientific purposes such as service network analysis, management, and control

    Mobility is the Message: Experiments with Mobile Media Sharing

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    This thesis explores new mobile media sharing applications by building, deploying, and studying their use. While we share media in many different ways both on the web and on mobile phones, there are few ways of sharing media with people physically near us. Studied were three designed and built systems: Push!Music, Columbus, and Portrait Catalog, as well as a fourth commercially available system – Foursquare. This thesis offers four contributions: First, it explores the design space of co-present media sharing of four test systems. Second, through user studies of these systems it reports on how these come to be used. Third, it explores new ways of conducting trials as the technical mobile landscape has changed. Last, we look at how the technical solutions demonstrate different lines of thinking from how similar solutions might look today. Through a Human-Computer Interaction methodology of design, build, and study, we look at systems through the eyes of embodied interaction and examine how the systems come to be in use. Using Goffman’s understanding of social order, we see how these mobile media sharing systems allow people to actively present themselves through these media. In turn, using McLuhan’s way of understanding media, we reflect on how these new systems enable a new type of medium distinct from the web centric media, and how this relates directly to mobility. While media sharing is something that takes place everywhere in western society, it is still tied to the way media is shared through computers. Although often mobile, they do not consider the mobile settings. The systems in this thesis treat mobility as an opportunity for design. It is still left to see how this mobile media sharing will come to present itself in people’s everyday life, and when it does, how we will come to understand it and how it will transform society as a medium distinct from those before. This thesis gives a glimpse at what this future will look like
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