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Tony Armstrong 《电子与电脑》2007,(8):23-25
引言 我们来看一下支撑互联网运行、传送成百上千万份YouTube视频、保持经济运转的大功率计算机服务器的功耗,从2000-2005年,服务器使用的电能翻了一番,到2010年可能再增长75%.换一个角度来看,在2005年,保持Google、微软、雅虎等互联网巨擘的数据中心运转所需的电量相当于14个1000 MW的发电厂发出的电量. 相似文献
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Mikael Svahnberg Tony Gorschek Thi Than Loan Nguyen Mai Nguyen 《Requirements Engineering》2013,18(1):85-103
Software products are usually developed for either a specific customer (bespoke) or a broader market (market-driven). Due to their characteristic, bespoke and market-driven development face different challenges, especially concerning requirements engineering. Many challenges are caused by an inadequate requirements engineering process, and hence there is a need for process improvement frameworks based on empirical research and industry needs. In a previous article we introduced Uni-REPM, a lightweight requirements engineering process assessment framework based on a review of empirically motivated practices in market-driven and bespoke requirements engineering literature. In this article, we validate this framework in academia as well as industry, in order to prepare Uni-REPM for widespread industry use. We conduct two validations; a static validation based on interviews with seven academic experts and a dynamic validation where Uni-REPM is applied in four industrial organisations. Uni-REPM is refined according to the feedback obtained in the validations. The study shows that Uni-REPM is a quick, simple, and cost-effective solution to assess the maturity level of the requirements engineering process of projects. Moreover, the assessment method using checklists is highly usable and applicable in various international development environments. 相似文献
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George H. Neilson Jr. Benjamin A. Carreras Daniel A. D'Ippolito Otto Gruber Mitsuru Kikuchi Kevin McGuire Douglass E. Post James D. Callen Patrick H. Diamond Kenneth W. Gentle E. Bickford Hooper Earl S. Marmar Cynthia Kieras Phillips Tony S. Taylor 《Journal of Fusion Energy》1999,18(3):117-160
This is the May 1996 report of a subpanel of the US Department of Energy Fusion Energy Sciences Advisory Committee (FESAC), charged with conducting a review of the progress, priorities and potential near-term contributions of TFTR, DIII-D and Alcator C-MOD (and other facilities as appropriate) as part of the transition to a Fusion Energy Sciences Program and produce an optimum plan for obtaining the most scientific benefit from them. 相似文献
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Evaluation of smart card security faced seemingly intractable problems of consistency and repeatability in its early days. The deeply specialised technologies, large parameter spaces for attacks, and the evolving attack types and countermeasures mean that the scope for variation in evaluation practice, and hence in evaluation conclusions, is potentially huge. The situation is further complicated by the fact that countermeasures against some types of attacks depend on both hardware and software, but there is also a need to evaluate hardware without specific software present at the time of evaluation. Stakeholders in the smart card world have formed a Community that has successfully created and applied interpretation of Common Criteria (ISO 15408) to deal with this problem and to achieve international mutual recognition of evaluation results. This paper discusses examples of the smart card security problem in order to illustrate some of the difficulties, and describes some of the interpretation that has been defined for rating the difficulty of an attack via calculation of an attack potential. It also considers the nature of the Community that has enabled the interpretation to be both defined and put into practice successfully. 相似文献
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In a Materials Requirements Planning (MRP) system, component lead times are generally assumed to be known and constant. Since a requirement of a MRP system is that components finish on time, slack is often built into component lead times to insure that actual job flowtimes equal planned job lead times. In this study, job characteristics and shop characteristics are investigated to determine which has a greater impact on predicting job flowtimes. This is accomplished by determining which characteristic most greatly influences the deviation of planned job lead times from actual job flowtimes. After identifying those factors which have the greatest influence on the job's flowtime, due date assignment rules are developed. A simulation study is then made to determine. which of the due date assignment rules perform best for varying product structures, as defined by various Bills of Materials (BOMs), and various shop conditions. Simulation test results are presented and discussed. 相似文献