We have designed and implemented game-themed programming assignment modules targeted specifically for adoption in existing introductory programming classes. These assignments are self-contained, so that faculty member...
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ISBN:
(纸本)9781605580579
We have designed and implemented game-themed programming assignment modules targeted specifically for adoption in existing introductory programming classes. These assignments are self-contained, so that faculty members with no background in graphics/gaming can selectively pick and choose a subset to combine with their own assignments in existing classes. This paper begins with a survey of previous results, followed by a description of the game-themed assignment modules. The paper then focuses on our efforts in assessing the assignments: including details of the procedures and instruments for evaluating student achievement of learning outcomes and attitudes towards the assignments, as well as the extra effort required of faculty to adopt the assignments in existing clases. Copyright 2008 ACM.
If you want to program a parallel computer, a purely functional language like Haskell is a promising starting point. Since the language is pure, it is by-default safe for parallel evaluation, whereas imperative langua...
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Multiagent systems have been proposed in the literature as a suitable architectural and implementation approach for cross-enterprise collaboration, due to their support for decentral decision-making and peer-to-peer c...
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ISBN:
(纸本)9783540790426
Multiagent systems have been proposed in the literature as a suitable architectural and implementation approach for cross-enterprise collaboration, due to their support for decentral decision-making and peer-to-peer coordination, loosely coupled interaction, modeling support for the notion of electronic institutions, and built-in adaptability mechanisms. While we agree with this general view, we argue that different application domain and different market constellations require different types of architecture. In this paper we look at the specific problem of selecting an information and communication technology (ICT) architecture for cross-enterprise business process (CBP) design and enactment. Therefore we identify three important architectural patterns for CBP enactment. We then propose a decision method for architecture selection based on the analytic hierarchy process (AHP) approach. Finally we illustrate the method by applying it to two application scenarios with differing characteristics. Robustness of the decision method is analyzed by performing a sensitivity analysis.
As memory transactions have been proposed as a language-level replacement for locks, there is growing need for well-defined semantics. In contrast to database transactions, transaction memory (TM) semantics are compli...
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ISBN:
(纸本)9781595939739
As memory transactions have been proposed as a language-level replacement for locks, there is growing need for well-defined semantics. In contrast to database transactions, transaction memory (TM) semantics are complicated by the fact that programs may access the same memory locations both inside and outside transactions. Strongly atomic semantics, where non-transactional accesses are treated as implicit single-operation transactions, remain difficult to provide without specialized hardware support or significant performance overhead. As an alternative, many in the community have informally proposed that a single global lock semantics [18, 10], where transaction semantics are mapped to those of regions protected by a single global lock, provide an intuitive and efficiently implementable model for programmers. In this paper, we explore the implementation and performance implications of single global lock semantics in a weakly atomic STM from the perspective of Java, and we discuss why even recent STM implementations fall short of these semantics. We describe a new weakly atomic Java STM implementation that provides single global lock semantics while permitting concurrent execution, but we show that this comes at a significant performance cost. We also propose and implement various alternative semantics that loosen single lock requirements while still providing strong guarantees. We compare our new implementations to previous ones, including a strongly atomic STM. [24] Copyright 2008 ACM.
Errors, inconsistences, incompletenesses and ambiguities in the requirements specification are major reasons for the failure of IT projects. Since the new major version 2 of the UML, the suitability of activity diagra...
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Errors, inconsistences, incompletenesses and ambiguities in the requirements specification are major reasons for the failure of IT projects. Since the new major version 2 of the UML, the suitability of activity diagrams for modeling requirements has increased significantly. UML 2 activity diagrams are based upon a completely reengineered metamodel including many new features and an improved semantic precision. We provide a formal syntax and operational semantics for activity diagrams to allow for fully executable models. Inspired by the scenario-based language of live sequence charts, some extensions for activity diagrams are proposed including a distinction between possible and mandatory behavior. The proposed semantics paves the way for formal reasoning and tool development that allows for early prototyping and validation by simulation.
A DSM protocol ensures that a thread can access data allocated on another machine using some consistency protocol. The consistency protocol can either replicate the data and unify replica changes periodically or the t...
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ISBN:
(纸本)9780889867741
A DSM protocol ensures that a thread can access data allocated on another machine using some consistency protocol. The consistency protocol can either replicate the data and unify replica changes periodically or the thread, upon remote access, can migrate to the machine that hosts the data and access the data there. There is a performance tradeoff between these extremes. Data replication suffers from a high memory overhead as every replicated object or page consumes memory on each machine. On the other hand, it is as bad to migrate threads upon each remote access since repeated accesses to the same distributed data set will cause repeated network communication whereas replication will incur this only once (at the cost of increased administration overhead to manage the replicas). We propose a hybrid protocol that uses selective replication with thread migration as its default. Even in the presence of extreme memory pressure and thread-migrations, our protocol reaches or exceeds the performance that can be achieved by means of manual replication and explicit changes of the application's code.
A seamless model-based methodology for requirements specification becomes increasingly the key to successful software systems engineering. The enhanced activity diagrams of UML 2 offer a promising intuitive modeling a...
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A seamless model-based methodology for requirements specification becomes increasingly the key to successful software systems engineering. The enhanced activity diagrams of UML 2 offer a promising intuitive modeling approach for requirements capturing. On this basis, we propose a formal syntax and operational semantics and extend activity diagrams to LADs (Live Activity Diagrams) by liveness-enriched constructs inspired by LSCs (Live Sequence Charts) for stating precise execution modalities. We aim at a tool-supported execution of LAD specifications allowing for early simulation and validation of requirements. We present an implementation of an LAD execution engine and describe the there upon suggested requirements engineering approach by means of an automotive case study.
In this paper we define a many-valued semantics for hybrid logic and we give a sound and complete tableau system which is proof-theoretically well-behaved, in particular, it gives rise to a decision procedure for the ...
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The paper presents the on-going EC-funded Tempus project "MSc and PhD studies in Aerospace Critical Computing" executed by the National Aerospace University, Kharkiv, Ukraine with the support of Newcastle Un...
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ISBN:
(纸本)9781605580760
The paper presents the on-going EC-funded Tempus project "MSc and PhD studies in Aerospace Critical Computing" executed by the National Aerospace University, Kharkiv, Ukraine with the support of Newcastle University and City University of London, UK and Åbo Akademi University, Turku, Finland. The state-of-the-art, completed work as well as the next steps of the development of master and doctoral courses for the specialty in critical software engineering, computer systems and networks are described. The inputs from each of the European consortium members are presented. Copyright 2008 ACM.
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