In recent years, several mature workflow modelling technologies have emerged. Nevertheless, they all present certain expressiveness limitations concerning primarily two aspects: first, none of them manages to adequate...
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In recent years, several mature workflow modelling technologies have emerged. Nevertheless, they all present certain expressiveness limitations concerning primarily two aspects: first, none of them manages to adequately capture all three core workflow perspectives, that is, control, data and resource;further, they typically are either data-centric or control flow oriented, being, therefore incapable of supporting domains that involve both execution patterns. In light of these issues, this study describes an innovative, highly expressive framework for workflow modelling, guided by the flexibility by design principle. Main characteristics of the proposed approach include the following: (i) it enables the comprehensive specification of workflow elements, providing extensive coverage of all aforementioned perspectives;(ii) it introduces the novel concept of assets, as a means for representing the entities being subject to the execution of workflow tasks;(iii) workflows are defined as ontologies;this, apart from the inherent benefits regarding formal semantics, offers also the advantage of their direct and transparent integration with an ontological information model;(iv) it allows the explicit modelling of both control and dataflows, thus being suitable for applications based on either of them or both of them combined;and (v) its expressiveness provides for the in-design expression of sophisticated security constraints.
To many managers and engineers who take part in virtual workgroup meetings, teleconferencing involves data sharing and audio, usually with slow-motion video. Their virtual meetings boil down to collaborative computin...
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To many managers and engineers who take part in virtual workgroup meetings, teleconferencing involves data sharing and audio, usually with slow-motion video. Their virtual meetings boil down to collaborative computing on desktop or laptop computers. Teleconferencing, or desktop conferencing, of this kind is best suited for individual computer users or for groups of 3-4 users per computer. For virtual but routine business conferences or for virtual classrooms-at-a-distance, real-life situations are best emulated by sharing data or still images, plus audio. data-sharing technologies, and the virtual conference systems built around them, have begun gaining ground. The remote sharing of data and video from a number of points requires software on a central server. Embedded in the software is a multipoint control unit, itself a software algorithm that coordinates the multidirectional flow of data. The selection of appropriate software and systems is discussed in detail.
Power reduction in modern embedded systems design is a challenging issue exacerbated by the complexity and heterogeneity of their architecture. In the field of Reconfigurable Video Coding (RVC), to challenge these iss...
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Power reduction in modern embedded systems design is a challenging issue exacerbated by the complexity and heterogeneity of their architecture. In the field of Reconfigurable Video Coding (RVC), to challenge these issues and cut-down time to market, dataflow-based techniques have been adopted. In particular, to master management and composability of dynamically reconfigurable systems, the authors have developed the multi-dataflow composer. Nevertheless, despite the RVC offers several different tools, in its reference design framework power management is still an open issue. To make some steps forward towards filling this gap, in this study, they address power management for coarse-grained reconfigurable systems combining structural and dynamic strategies, both to be applied at the dataflow level.
The mobile crowdsourcing network (MCN) is a promising network architecture that applies the principles of crowdsourcing to perform tasks with human involvement and powerful mobile devices. However, it also raises some...
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The mobile crowdsourcing network (MCN) is a promising network architecture that applies the principles of crowdsourcing to perform tasks with human involvement and powerful mobile devices. However, it also raises some critical security and privacy issues that impede the application of MCNs. In this article, in order to better understand these critical security and privacy challenges, we first propose a general architecture for a mobile crowdsourcing network comprising both crowdsourcing sensing and crowdsourcing computing. After that, we set forth several critical security and privacy challenges that essentially capture the characteristics of MCNs. We also formulate some research problems leading to possible research directions. We expect this work will bring more attention to further investigation on security and privacy solutions for mobile crowdsourcing networks.
Proposes a general design of an integrated total quality information system involving the Quality Function Deployment process. Utilization of dataflow diagram.
Proposes a general design of an integrated total quality information system involving the Quality Function Deployment process. Utilization of dataflow diagram.
We present a technique for pipelining heterogeneous multiprocessor systems, macro pipelining based scheduling. The problem can be identified as a combination of optimal task/processor assignment to pipeline stages as ...
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We present a technique for pipelining heterogeneous multiprocessor systems, macro pipelining based scheduling. The problem can be identified as a combination of optimal task/processor assignment to pipeline stages as well as a scheduling problem. We propose a new technique based on iterative applications of partitioning and scheduling schemes whereby the number of pipeline stages are identified and the scheduling problem is solved. The pipeline cycle is optimized in two steps. The first step finds a global coarse solution using the Ratio Cut Partitioning technique. This is subsequently improved by the iterative architecture driven partitioning and the repartitioning and time axis relabeling techniques of the second step. We have considered a linear interprocessor communication cost model in scheduling. The proposed technique is applied to several examples. We find that for these examples, the proposed macro pipelining based scheduling can improve the throughput rate several times that of the conventional homogeneous multiprocessor scheduling algorithms.
This paper considers various aspects of static analysis of C# programs in order to detect the maximum number of software bugs in an acceptable time. A complete cycle of software static analysis is described with the m...
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This paper considers various aspects of static analysis of C# programs in order to detect the maximum number of software bugs in an acceptable time. A complete cycle of software static analysis is described with the main focus being placed on the specifics of the C# language. Some methods are discussed that take into account popular features of C# at all levels of analysis: call graph and control flow graph construction, dataflow analysis, as well as context- and path-sensitive interprocedural analysis. A symbolic execution method is proposed, which is based on the works devoted to the Bounded Model Checking (BMC) and the Saturn Software Analysis Project. A memory model is described that enables an accurate intraprocedural analysis and allows one to create compact representations of error conditions associated with functions, which are essential for interprocedural analysis. A special attention is paid to the optimizations that occur during path-sensitive analysis of error conditions. The conditions need to be optimized in terms of size, because path-sensitive interprocedural analysis requires saving a large number of conditions for each analyzed function. The conditions are resolved using advanced SMT solvers (such as the Microsoft Z3 Prover). This paper also considers various approaches to modeling the behavior of library functions: based on a summary containing a set of properties required for analysis, or based on simplified implementations in C#. All the discussed solutions are implemented in the SharpChecker static analysis tool and are tested on a number of open-source projects from 1.5 thousand to 1.35 million lines of code.
作者:
Rabinovich, ATel Aviv Univ
Dept Comp Sci Raymond & Beverly Sackler Fac Exact Sci IL-69978 Tel Aviv Israel
Modularity reflects the Frege Principle: any two expressions expr(1) and expr(2) which have the same meaning (semantics) can be replaced by each other in every appropriate context C[] without changing the meaning of t...
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Modularity reflects the Frege Principle: any two expressions expr(1) and expr(2) which have the same meaning (semantics) can be replaced by each other in every appropriate context C[] without changing the meaning of the overall expression. In [18] we identified observable relations and nets of observable relations as appropriate tools for the investigation of dataflow networks over nondeterministic agents. The observable relations are the Input-Output behaviors of tin general nondeterministic) dataflow agents. Moreover, the semantics of nets of observable relations is consistent with the input-output behavior of dataflow agents. In [18, 19] we showed that the main source of the Brock-Ackerman anomaly [2] is in the semantics of nets of relations. But it turns out that this semantics is not modular. The central objective of this paper is the characterization of modular classes of relations and hence indirectly the set of dataflow nets without anomalies. Another major theme which plays a technical role in this characterization, but is interesting in its own, is the expressibility for relational nets. The investigation also reveals the interesting role played by stable functions introduced by Berry [3].
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