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Wireless Networks - This paper presents a structural equation model that relates knowledge coordination with access to information in the process of implementing Six Sigma and their impact on the...  相似文献   
13.
戴如梅 《通信世界》2006,(29):22-23
欧盟的电信管制陷入了与国家政体冲突的泥潭中,尽管高层有一些关于改革的勇敢论调,但事实胜于雄辩。欧盟所规定的电信规则设想在这个有25个国家、超过4.5亿人口的市场,以远远超出这个范围的影响创造一个公平的竞争环境,它能奏效吗?于布鲁塞尔制定的电信政策在许多方面呈现多极化趋向,这反映了对泛欧“超级国家”实体更大的争议。根据每天问题的不同,随着观点的转移,欧洲电信规则被同等程度地喜爱和痛恨着。对一方来说很协调的东西,对另一方则成了毫无根据  相似文献   
14.
Point-matching is a widely applied image registration method and many algorithms have been developed. Registration of 2-D electrophoresis gels is an important problem in biological research that presents many of the technical difficulties that beset point-matching: large numbers of points with variable densities, large nonrigid transformations between point sets, paucity of structural information and large numbers of unmatchable points (outliers) in either set. In seeking the most suitable algorithm for gel registration we have evaluated a number of approaches for accuracy and robustness in the face of these difficulties. Using synthetic images we test combinations of three algorithm components: correspondence assignment, distance metrics and image transformation. We show that a version of the iterated closest point (ICP) algorithm using a non-Euclidean distance metric and a robust estimation of transform parameters provides best performance, equalling SoftAssign in the presence of moderate image distortion, and providing superior robustness against large distortions and high outlier proportions. From this evaluation we develop a gel registration algorithm based on robust ICP and a novel distance metric combining Euclidean, shape context and image-related features. We demonstrate the accuracy of gel matching using synthetic distortions of real gels and show that robust estimation of transform parameters using M-estimators can enforce inverse consistency, ensuring that matching results are independent of the order of the images.  相似文献   
15.
The shift of electronics industry towards the use of lead-free solders in components manufacturing brought also the challenge of addressing the problem of tin whiskers. Manufacturers of high reliability and safety critical equipment in sectors such as defence and aerospace rely increasingly on the use of commercial-of-the-shelf (COTS) electronic components for their products and systems. The use of COTS components with lead-free solder plated terminations comes with the risks for their long term reliability associated with tin whisker growth related failures. In the case of leaded type electronic components such as Quad Flat Package (QFP) and Small Outline Package (SOP), one of the promising solutions to this problem is to “re-finish” the package terminations by replacing the lead-free solder coatings on the leads with conventional tin–lead solder. This involves subjecting the electronic components to a post-manufacturing process known as Hot Solder Dip (HSD). One of the main concerns for adopting HSD (refinishing) as a strategy to the tin whisker problem is the potential risk for thermally induced damage in the components when subjected to this process.  相似文献   
16.
We present an algorithmically-aware, high-level partitioning methodology for discrete cosine transforms (DCT) targeted to distributed hardware architectures. The methodology relies on the exploration of alternate DCT formulations as part of the partition optimization process. To the best of our knowledge, no previously proposed DCT algorithm exists that is capable of consistently producing alternate regular formulations for an n-size DCT. Hence, a new Cooley-Tukey-like DCT factorization algorithm was developed to allow exploration of alternate formulations as part of the partitioning optimization process. The use of our factorization mechanism along with a greedy strategy to explore the space of equivalent DCT formulations yielded partitioning solutions with as much as 18% reduction in latency and 83% reduction in run-time as compared to previously proposed regular DCT formulations.
Domingo RodríguezEmail:
  相似文献   
17.
Multicasting refers to the transmission of data from a source node to multiple destination nodes in a network. Group multicasting is a generalization of multicasting whereby every member of a group is allowed to multicast messages to other members that belong to the same group. The routing problem in this case involves the construction of a set of low cost multicast trees with bandwidth requirements, one for each member of the group for multicasting messages to other members of the group. In this paper, we examine this routing problem with an additional requirement that member nodes are allowed to join and leave the multicasting group anytime during a session. We call this problem, the dynamic group multicast routing problem (DGMRP). In this paper, we proposed three heuristic algorithms to generate a set of low cost multicast trees with dynamic group membership. Results from our empirical study shows that the one of the proposed algorithms, called Maximum bandwidth bottleneck path selection algorithm (MBBPS), achieves better utilization of bandwidth resources as compared with the other two algorithms which are based on a greedy approach. In addition MBBPS performs better in terms of cost when the bandwidth is not sufficient in the network. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   
18.
晶圆表面如果有一层薄且均匀的流体边界层,将有助于克服光刻图形带来的挑战,得到更均匀的金属沉积层。  相似文献   
19.
数据信息永远不能满足整个社会的需求.因此,处理信息的计算、存储和交换系统对于更大数据吞吐能力的需求也在不断提高.在过去的五年时间里,处理能力有了巨大的提升,因此,更加迫切地需要适用于系统间移动海量数据更好、更高效的方法.  相似文献   
20.
Multifunctional theranostic systems with good biocompatibility, strong clinical imaging capability, and target specificity are the desired features of future medicine. Here, the design of a theranostic nanocomposite capable of simultaneous targeting and imaging of the cancer cells is presented. It releases its drug payload by a controlled release mechanism. The nanocomposite contains luminescent gold nanocluster (L‐AuNC) photostable and biocompatible diagnostic probes conjugated to a folic acid (FA)‐modified pH‐responsive amphiphilic polymeric system for controlled drug release. The nanocomposite uses a core‐satellite structure to encapsulate hydrophobic drugs and releases the drug payload in mildly acidic endosomal/lysosomal compartments by the action of the pH‐labile linkages in the polymer. In vivo studies show the selective accumulation of the FA‐conjugated nanocomposite in tumor tissues by folate‐receptor‐mediated endocytosis. These findings demonstrate the potential of the nanocomposite as a nontoxic, folate‐targeting, pH‐responsive drug carrier that is useful for the early detection and therapy of folate‐overexpressing cancerous cells.  相似文献   
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