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《Information Technology for Development》2012,18(4):686-714
ABSTRACTA review of existing Electronic Commerce adoption literature reveals that the prevailing theoretical frameworks implicitly assume that organizations are independent and have complete control over their decisions to adopt innovations. Given the fact that organizations are often constrained by and depend on their environment and exchange partners to survive, this paper proposes that Resource Dependency can either be a facilitator or inhibitor of the role of Technological, Organizational, and Environmental (TOE) motivating factors. Using 239 valid responses from supply chain managers in Jordan, the study found partial support for the role of Resource Dependency as a moderator. The findings provide insights on how Resource Dependency between partners drives different patterns of innovation acceptance among potential adopters, regardless of several technological and organizational motivations to innovate. The results suggest that predicting how innovation is diffused within a market needs a detailed understanding of the inter-dependence structure among the supply chain members. 相似文献
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We present new and effective lower bounds for the resource constrained project scheduling problem. This problem is widely known to be notoriously difficult to solve due to the lack of lower bounds that are both tight and fast. In this paper, we propose several new lower bounds that are based on the concept of energetic reasoning. A major contribution of this work is to investigate several enhanced new feasibility tests that prove useful for deriving new lower bounds that consistently outperform the classical energetic reasoning-based lower bound. In particular, we present the results of a comprehensive computational study, carried out on 1560 benchmark instances, that provides strong evidence that a deceptively simple dual feasible function-based lower bound is highly competitive with a state-of-the-art lower bound while being extremely fast. Furthermore, we found that an effective shaving procedure enables to derive an excellent lower bound that often outperforms the best bound from the literature while being significantly simpler. 相似文献
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Vladimir Shestak Edwin K.P. Chong Anthony A. Maciejewski Howard Jay Siegel 《Journal of Parallel and Distributed Computing》2012
The problem of finding efficient workload distribution techniques is becoming increasingly important today for heterogeneous distributed systems where the availability of compute nodes may change spontaneously over time. Resource-allocation policies designed for such systems should maximize the performance and, at the same time, be robust against failure and recovery of compute nodes. Such a policy, based on the concepts of the Derman–Lieberman–Ross theorem, is proposed in this work, and is applied to a simulated model of a dedicated system composed of a set of heterogeneous image processing servers. Assuming that each image results in a “reward” if its processing is completed before a certain deadline, the goal for the resource allocation policy is to maximize the expected cumulative reward. An extensive analysis was done to study the performance of the proposed policy and compare it with the performance of some existing policies adapted to this environment. Our experiments conducted for various types of task-machine heterogeneity illustrate the potential of our method for solving resource allocation problems in a broad spectrum of distributed systems that experience high failure rates. 相似文献
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The parallelism attained by the use of Field Programmable Gate Arrays (FPGAs) has shown remarkable potential for accelerating control systems applications. This comes at a time when well established methods based on inherited serial Central Processor Units (CPUs) cannot guarantee solutions for the increasing execution speed demands. However, the transition from serial to parallel architectures represents a tremendous challenge due to overwhelming numbers of unexplored options and conflicting factors. The work presented achieves a parallelisation characterisation for generic MIMO systems using stand-alone FPGA implementations. The main contribution is that a very fine subset of possible serial/parallel implementations is obtained. This is used to achieve a flexible trade-off between cost and performance. Automatic optimisation of latency, occupied FPGA area and execution speed is attained and justified in respect to most of the feasible scenarios. 相似文献
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随着国内外政治、治安局势的不断变化,城市高清网络视频监控系统已经成为公安机关依法履行职能打击违法犯罪的一个重要手段。本文介绍了一种城市高清网络视频监控系统建设方案及技术要求,并以此为框架进行概括总结,系统基本分为前端监控资源采集、监控资源接入、联网集中管理平台、图像资源存储以及图像资源共享平台建设等部分。 相似文献