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JinbaekKim ArieShoshani 《高能物理与核物理计算国际会议公报》2001,(1):286-293
Large High Energy and Nuclear Physics(HENP)databases are commonly stored on robotic tape systems because of cost considerations.Later,selected subsets of the data are cached into disk caches for analysis or data mining.Because of the relatively long time to mount,seek,and read a tape,it is important to minimize the number of times that data is cached into disk.Having too little disk cache will force files to be removed from disk prematurely,thus reducing the potential of their sharing with other users .Similarly,having too few tape drives will not make good use of a large disk cache,as the throughput from the tape system will form the bottleneck.Balancing the tape and disk resources is dependent on the patterns of the requests to the data.In this paper,we describe a simulation that characterizes such a system in terms of the rsources and the request patterns.We learn from the simulation which parameters affect the performance of the system the most.We also observe from the simulation that,there is a point beyond which it is not worth investing in additional resources as the benefit is too marginal.We call this point the “point-of -no-benefit“(or PNB),and show that using this concept we can more easily discover the relationship of various parameters to the performance of the system. 相似文献
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提出了一种基于人脸重要特征的人脸识别方法,首先选取人脸的重要特征并将其具体化,对得到的重要特征进行主成分分析,然后用支持向量机(Support Vector Machine,SVM)设计重要特征分类器来确定测试人脸图像中重要特征,同时设计支持向量机(SVM)人脸分类器,确定人脸图像的所属类别.对ORL人脸图像数据库进行仿真实验,结果表明,该方法要优于一般的基于整体特征的人脸识别方法并有较强的鲁棒性. 相似文献
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The GAuDI architecture and framework are designed to provide a comon infrastructure and environment for simulation,filtering,reconstruction and analysis applications.Initially developed for the LHCb experiment,GAUDI has been adopted and extended by the ATLAS experiment and adopted by several other experiments including GLAST and HARP.we describe the properties and concepts embodied by GAUDI and recent functionality additions and how the project has evolved from a product developed by a tightly-knit team in a single site,to a collaboration between multiple teams at geographically dispersed sites,based loosely on open source concepts.We describe the management infrastructure as well as how we accommodate experment -specific extensions and adaptations as well as an experiment-neutral kernel. 相似文献