Lively Fabrik is a Web-based general-purpose end-user programming environment. Based on the Lively Kernel, Lively Fabrik extends the ideas of the original Fabrik system by empowering end-users to create interactive We...
详细信息
ISBN:
(纸本)9780769536200
Lively Fabrik is a Web-based general-purpose end-user programming environment. Based on the Lively Kernel, Lively Fabrik extends the ideas of the original Fabrik system by empowering end-users to create interactive Web content entirely within their Web browsers. Web applications created with Lively Fabrik typically combine Web sources, data manipulation, and interactive user interface elements. the result can be a Mashup, but due to the powerful underlaying system, any general-purpose application. Connecting components with wires and scripting components is all that is needed to do so.
Kahn Process Networks is an appealing model of computation for programming and mapping applications onto multi-processor platforms. Autonomous processes communicate through unbounded FIFO channels in absence of a glob...
详细信息
ISBN:
(纸本)9781605586281
Kahn Process Networks is an appealing model of computation for programming and mapping applications onto multi-processor platforms. Autonomous processes communicate through unbounded FIFO channels in absence of a global scheduler. We derive Kahn process networks from sequential applications using the pn compiler, but the derived networks do not necessarily meet the performance requirements. Process partitioning transformations can achieve a more balanced network improving the performance results significantly. there are a number of process partitioning transformations that can be used, but no hints are given to the designer which transformation should be applied to minimize, for example, the execution time. therefore, we investigate a compile-time approach for selecting the best transformation candidate and show results on a Xilinx Virtex 2 FPGA and the Cell BE processor. Copyright 2009 ACM.
Built upon a shared wireless medium, wireless network is particularly vulnerable to jamming attacks. the ability to recover from attacks and maintain an acceptable level of service degradation is a crucial aspect in t...
详细信息
ISBN:
(纸本)9781424450473
Built upon a shared wireless medium, wireless network is particularly vulnerable to jamming attacks. the ability to recover from attacks and maintain an acceptable level of service degradation is a crucial aspect in the design of a wireless network. To address this issue, this paper investigates the network restoration solutions via the joint design of traffic rerouting, channel re-assignment, and scheduling. Efficient routing and channel assignment schemes can relieve the interference caused by boththe normal network nodes and the jamming nodes. therefore, based on the necessary conditions of schedulability, we first formulate the optimal network restoration problem as linear programming problem, which gives an upper bound on the achievable network throughput. After we solve the LP problems, we have a set of flows assigned to edges that have been assigned to different channels. And based on the LP solutions, we provide a greedy scheduling algorithm using dynamic channel assignment, which schedules boththe network traffic and the jamming traffic. In particular, we consider two strategies, namely global restoration and local restoration, which can support a range of tradeoffs between the restoration latency and network throughput after restoration. To quantitatively evaluate the impact of jamming attacks during and after restoration, we define two performance degradation indices, transient disruption index (TDI) and throughput degradation index (thI). Finally, extensive performance evaluations are performed to study the impact of various jamming scenarios in a multi-hop multi-channel wireless network.
the cost analysis of water systems projects is an evaluation of various alternatives. It can be used to identify the feasible alternative as per economic criteria to estimate the sensitivity of the project outputs. Co...
详细信息
ISBN:
(纸本)9789604741052
the cost analysis of water systems projects is an evaluation of various alternatives. It can be used to identify the feasible alternative as per economic criteria to estimate the sensitivity of the project outputs. Cost analysis is intended to guide the decisions on the use of water resources and economic conditions and to provide alternatives for ranking different water development and management policies. In this paper, we present an optimization model to minimize the costs for obtaining water needs of various users. the proposed model takes into account the costs to obtain water depending on the source and the user. Model constraints include demands, limitations in the capacity of the various water sources and legal and structural specifications that must be followed in terms of water allocation. For illustration purposes, the model is applied to a simple case study. However, since our model is generic it can be applied to any water system.
Repository-based revision control systems such as CVS, RCS, Subversion, and GIT, are extremely useful tools that enable software developers to concurrently modify source code, manage conflicting changes, and commit up...
详细信息
ISBN:
(纸本)9781605585987
Repository-based revision control systems such as CVS, RCS, Subversion, and GIT, are extremely useful tools that enable software developers to concurrently modify source code, manage conflicting changes, and commit updates as new revisions. Such systems facilitate collaboration with and concurrent contribution to shared source code by large developer bases. In this work, we investigate a framework for "performance-aware" repository and revision control for Java programs. Our system automatically tracks behavioral differences across revisions to provide developers with feedback as to how their change impacts performance of the application. It does so as part of the repository commit process by profiling the performance of the program or component, and performing automatic analyses that identify differences in the dynamic behavior or performance between two code revisions. In this paper, we present our system that is based upon and extends prior work on calling context tree (CCT) profiling and performance differencing. Our framework couples the use of precise CCT information annotated with performance metrics and call-site information, with a simple tree comparison technique and novel heuristics that together target the cause of performance differences between code revisions without knowledge of program semantics. We evaluate the efficacy of the framework using a number of open source Java applications and present a case study in which we use the framework to distinguish two revisions of the popular FindBugs application. Copyright 2009 ACM.
Testing software can be particularly challenging for a small or mid-size firm interested in commercially distributing their software to a wide variety of users. Testing is clearly an important part of any software dev...
详细信息
the proceedings contain 7 papers. the topics discussed include: self-adjusting computation with delta ML;spider spinning for dummies;from reduction-based to reduction-free normalization;libraries for generic programmi...
ISBN:
(纸本)3642046517
the proceedings contain 7 papers. the topics discussed include: self-adjusting computation with delta ML;spider spinning for dummies;from reduction-based to reduction-free normalization;libraries for generic programming in Haskell;dependently typed programming in agda;a tutorial on parallel and concurrent programming in Haskell;and an iTask case study: a conference management system.
Workflow systems are automated systems in which tasks are coordinated by assigning them to either humans or computers. Contemporary workflow systems are static and not very flexible. In these lecture notes, we discuss...
详细信息
ISBN:
(纸本)9783642046513
Workflow systems are automated systems in which tasks are coordinated by assigning them to either humans or computers. Contemporary workflow systems are static and not very flexible. In these lecture notes, we discuss the iTask system: a combinator library for specifying workflows in the functional language Clean. this system offers several advantages when compared to commercial systems: tasks are statically typed;tasks can be higher order, the combinators are fully compositional, and dynamic and recursive workflow can be specified. Moreover, the specification is an executable specification offering a web-based multi-user workflow system. In this paper we describe the iTask system using a conference management system as the running example to illustrate the expressive power of functional and generic programming in a real-world domain.
A class of the hybrid optimal control problem is formulated and a hybrid dynamic programming principle (DPP) is presented which constitutes a generalization of the celebrated dynamic programming principle of Richard B...
详细信息
We propose a new method for the recognition and retrieval of shapes whose contours are simple closed curves. First, we give a new shape representation by a sequence of 2D-vectors of angles, which is independent of rot...
详细信息
ISBN:
(纸本)9780769535203
We propose a new method for the recognition and retrieval of shapes whose contours are simple closed curves. First, we give a new shape representation by a sequence of 2D-vectors of angles, which is independent of rotation and scaling. Each 2D-vector captures the local shape information around a point in the contour. Next, we apply a dynamic programming method to match the points of two contours and identify the outlier (unmatched) points in each contour with respect to the other. then, we define the similarity of a pair of contours by the number of unmatched points and the matching cost for the matched points. Finally, the recognition and retrieval are done using the nearest-neighbor method. Our experiments on MPEG-7 database show that the performance of the new algorithm is very similar to that of the best-known algorithms in the literature in spite of its significantly less computational complexity and simplicity.
暂无评论