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211.
Frank R. Ihmig 《低温学》2006,46(4):312-320
This paper describes low-temperature electronics for cryogenic applications, especially for a new technique for living-cell storage near liquid-nitrogen temperatures. Central is the reliable coupling of a sample carrier to cryo-tolerant electronics, particularly memory devices storing continuity of care records, lab workflows, and other useful documentation. We present (1) a two-year study of the performance and data retention of Flash-Memory devices in a controlled cryogenic environment, (2) a cryogenic multiplexer allowing multiple, cold Flash-Memories to share a communication channel, and (3) results for radio frequency identification tags immersed in liquid nitrogen. 相似文献
212.
Frank Schilder Werner Vogt Stephan Schreiber Hinke M. Osinga 《International journal for numerical methods in engineering》2006,67(5):629-671
Quasi‐periodic oscillations and invariant tori play an important role in the study of forced or coupled oscillators. This paper presents two new numerical methods for the investigation of quasi‐periodic oscillations. Both algorithms can be regarded as generalizations of the averaging and the harmonic (spectral) balance methods. The algorithms are easy to implement and require only minimal a priori knowledge of the system. Most importantly, the methods do not depend on an a priori co‐ordinate transformation. The methods are applied to a number of illustrative examples from non‐linear electrical engineering and the results show that the methods are efficient and reliable. In addition, these examples show that the presented algorithms can also continue through regions of sub‐harmonic (phase‐locked) resonance even though they are designed only for the quasi‐periodic case. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
213.
Frank Engelskirchen Peter Heinzig 《电力设备》2005,6(12):93-95
介绍了高压直流输电(HVDC)变压器及平波电抗器的磁芯设计、高压直流绕组设计、导线引出端(换流阀绕组)、直流套管设计方案,举例说明了高压换流变压器的制造过程与传统变压器制造过程的不同。并通过高压换流变压器试验,说明如材料、环境等条件对直流工作的影响。最后介绍了一些高压换流变压器的现场维修经验。 相似文献
214.
Weaver Kathryn E.; Llabre María M.; Durán Ron E.; Antoni Michael H.; Ironson Gail; Penedo Frank J.; Schneiderman Neil 《Canadian Metallurgical Quarterly》2005,24(4):385
The authors tested a structural model that incorporated age, time since diagnosis, social support, coping, and negative mood as predictors of medication adherence and HIV viral load on 188 men and 134 women on highly active antiretroviral therapy (HAART). The authors used psychosocial latent factors formed from baseline measures to predict latent factors of adherence, as assessed by electronic monitoring and self-report, and viral load defined by indicators assessed over a 15-month period. Results from the model indicate that greater negative mood and lower social support are related to greater use of avoidance-oriented coping strategies. Use of these coping strategies by patients on HAART is related to poorer medication adherence and, subsequently, higher viral load. This model advances researchers' understanding of the contribution of psychosocial variables in predicting treatment adherence and disease progression in HIV-positive men and women. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
215.
The emergence of worldwide communications networks and powerful computer technologies has redefined the concept of distance learning and the delivery of engineering education content. This article discusses the Sloan Consortium's quest for quality, scale, and breadth in online learning, the impact on both continuing education of graduate engineers as well as degree‐seeking engineering students, and the future of engineering colleges and schools as worldwide providers of engineering education. 相似文献
216.
Frank Rice 《硅谷》2005,(6):112-118
引言
Micmsoft Visual Studio 2005 Tools for the Microsoft Office System(Visual Studio 2005 Tools for Office)为要编写Microsoft Office Word 2003和Microsoft Office Excel 2003后台代码的开发提供了许多工具.以满足各种业务场景的需要。比如.您可能想犏写业务逻辑.以符理用Excel工作表中预算数据,或者希望使用通过Web服务获得的销售数据填充Word文档中的表格。如果已经在使用Microsoft Visual Studio.NET,就可以使用Visual Studio 2005 Tools for Office来满足这些场景以及许多其他的场景的需要。 相似文献
217.
Unrelated parallel machine scheduling with setup times and a total weighted tardiness objective 总被引:2,自引:0,他引:2
This paper presents several search heuristics and their performance in batch scheduling of parallel, unrelated machines. Identical or similar jobs are typically processed in batches in order to decrease setup times and/or processing times. The problem accounts for allotting batched work parts into unrelated parallel machines, where each batch consists of a fixed number of jobs. Some batches may contain different jobs but all jobs within each batch should have an identical processing time and a common due date. Processing time of each job of a batch is determined according to the machine group as well as the batch group to which the job belongs. Major or minor setup times are required between two subsequent batches depending on batch sequence but are independent of machines. The objective of our study is to minimize the total weighted tardiness for the unrelated parallel machine scheduling. Four search heuristics are proposed to address the problem, namely (1) the earliest weighted due date, (2) the shortest weighted processing time, (3) the two-level batch scheduling heuristic, and (4) the simulated annealing method. These proposed local search heuristics are tested through computational experiments with data from dicing operations of a compound semiconductor manufacturing facility. 相似文献
218.
Jatinder N. D. Gupta Frank Werner Gunnar Wulkenhaar 《International Transactions in Operational Research》2003,10(3):267-294
This paper considers two-machine open shop problems with secondary criteria where the primary criterion is the minimization of makespan and the secondary criterion is the minimization of the total flow time, total weighted flow time, or total weighted tardiness time. In view of the strongly NP-hard nature of these problems, two polynomially solvable special cases are given and constructive heuristic algorithms based on insertion techniques are developed. A strongly connected neighborhood structure is derived and used to develop effective iterative heuristic algorithms by incorporating iterative improvement, simulated annealing and multi-start procedures. The proposed insertion and iterative heuristic algorithms are empirically evaluated by solving problem instances with up to 80 jobs. 相似文献
219.
Miguel Rio Andrea di Donato Frank Saka Nicola Pezzi Richard Smith Saleem Bhatti Peter Clarke 《Journal of Grid Computing》2003,1(4):329-343
This paper reports on different efforts to provide quality of service (QoS) Networking to Grid applications done in the context of the MB-NG, GRS and DataTAG EU projects. These are leading edge network research projects involving more that 50 researchers in the UK, Europe and North America, concerned with the development and testing of protocols and standards for the next generation of high speed networks. We have implemented and tested the Differentiated Services Architecture (DiffServ) in a multi-domain, 2.5 Gbits/s network (the first such deployment) defining appropriate Service Level Agreements (SLAs) to be used between administrative domains to guarantee end-to-end Quality of Service. We characterised several hardware implementations of DiffServ and concluded on their appropriateness for several network scenarios. Since current and future Grid applications will have to use modified mechanisms of congestion control we have evaluated old and new TCP implementations over a Differentiated Services Networks. These quality of service tests have also included innovative MPLS (Multi-Protocol Label Switching) experiments to establish guaranteed bandwidth connections to Grid applications in a fast and efficient way. We have also developed a software based bandwidth broker architecture for Grids based on IETF standards which allows applications to transparently request dynamic and advanced reservations and implemented it in a real experimental network. We finally report on experiences delivering Quality of Service networking to high performance applications like Particle Physics data transfer and High Performance Computation. This includes quantitative results on the performance improvements that QoS brought to real data transfers in the context of High Performance Computing. 相似文献
220.
Hyongsuk Kim Tmas Roska Leon O. Chua Frank Werblin 《International Journal of Circuit Theory and Applications》2003,31(4):329-346
A high speed target detection and tracking algorithm for a CNN‐UM chip is presented in this paper. The target confidence value is computed based on the fusion of target existence probabilities of features using products of weighted sums. The target decision is done with such a confidence value and target initiation is done through the temporal accumulation of the confidence. The probability of the target existence for each feature is created in the region of influence depending on the reliability and the strength of the feature. By virtue of the analogic parallel processing structure of the CNN‐UM (Roska T, Chua LO. The CNN universal machine: an analogic array computer. IEEE Trans. Circuits Systems II 1993; CAS‐40 : 163–173), real time tracking can be achieved with presently available technologies with the speed of several kilo‐frames per second. Due to the utilization of multiple features of target, robust target detection is possible via the proposed algorithm. On‐chip experiments of the proposed target‐tracking algorithm have been done and properties of the proposed approach are disclosed through the various experiments. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献