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排序方式: 共有8862条查询结果,搜索用时 15 毫秒
981.
Prof. Dr. Thomas Hess Dipl.-Wirtsch.Inf. Stefan Figge Dipl.-Sozw. Heidemarie Hanekop Dipl.-Inf. Iris Hochstatter Dipl.-Kffr. Barbara Rauscher Prof. Dr. Dieter Hogrefe Dipl.-Math. André Riedel Dipl.-Inf. Marco Zibull Dipl.-Kfm. Christian Kaspar Dipl.-Ing. Markus Richter 《WIRTSCHAFTSINFORMATIK》2005,47(1):6-16
Mobile data communication applications, referred to in this paper as mobile applications, were one of the technological innovation and investment targets in recent years. From the past it became obvious that mono-disciplinary approaches to investigate mobile applications have shortcomings when it comes to successful innovation and investment decisions as interdependencies are insufficiently addressed. The paper therefore aims at structuring the scientific contributions of computer science, business economics and sociology in the context of mobile applications to approximate a holistic understanding comprising technological feasibility, economic opportunities and human needs. 相似文献
982.
与SMART~(R)扇形段技术配合使用的自动控制铸坯锥度(ASTC)的发展和应用,减少了中心偏析,使铸坯内部质量得到明显改进。遥控调整辊缝锥度和动态轻压下的应用,也能满足瞬间浇铸条件的特殊要求。到2003年5月止,在芬兰、美国、意大利、奥地利、韩国和中国共有9台11流板坯连铸机使用SMART~(R)/ASTC技术进行操作。另外,还有7台18流其它类型的连铸也已订购采用这项技术。SMART~(R)/ASTC技术对于在板坯和大方坯连铸机上浇铸所有的钢种都很理想。在大方坯连铸机上应用的实例是计划安装在中国攀枝花钢铁集团的6流大方坯连铸机。 相似文献
983.
Jos-Manuel Belenguer Enrique Benavent Philippe Lacomme Christian Prins 《Computers & Operations Research》2006,33(12):3363
This paper presents a linear formulation, valid inequalities, and a lower bounding procedure for the mixed capacitated arc routing problem (MCARP). Moreover, three constructive heuristics and a memetic algorithm are described. Lower and upper bounds have been compared on two sets of randomly generated instances. Computational results show that the average gaps between lower and upper bounds are 0.51% and 0.33%, respectively. 相似文献
984.
Admitting banking in emissions trading systems reduces overall compliance costs by allowing for inter-temporal flexibility: cost savings can be traded over time. However, unless individual EU Member States (MS) decide differently, the transfer of unused allowances from the period of 2005–2007 into the first commitment period under the Kyoto Protocol, i.e. 2008–2012, will be prohibited. In this paper, we first explore the implications of such a ban on banking when initial emission targets are lenient. This analysis is based on a simulation which was recently carried out in Germany with companies and with a student control group. The findings suggest that a EU-wide ban on banking would lead to efficiency losses in addition to those losses which arise from the lack of inter-temporal flexibility. Second, we use simple game-theoretic considerations to argue that, under reasonable assumptions, such a EU-wide ban on banking will be the equilibrium outcome. Thus, to avoid a possible prisoners’ dilemma, MS should have co-ordinated their banking decisions. 相似文献
985.
It is an accepted, albeit puzzling finding that negative priming (NP) hinges on the presence of distractors in probe displays. In three experiments without probe distractors, the authors yielded evidence that response-biasing processes based on the contingency between prime and probe displays may have caused this finding. It is argued that it is of help in standard NP experiments to process the distractor in the prime display in order to prepare the response to the probe target. When this contingency was removed (Experiments 2 and 3), NP was reliably observed without probe distractors, whereas no NP emerged if the design contained the typical contingency (Experiment 1). For this reason, the data suggest that the absence of NP, which is usually observed under these conditions, may be due to a contingency-based component. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
986.
Christian Hoymann 《Wireless Personal Communications》2006,36(4):363-385
Advanced antenna technologies and algorithms have been developed during the last years. But until today, advanced antenna algorithms in the physical layer and the modes of operation in medium access layers have not been integrated in modern wireless systems. As one of the first standards the metropolitan area network IEEE 802.16 provides means to support smart antenna techniques.After a detailed introduction of the medium access control layer this article outlines the support of space division multiple access (SDMA) techniques by the wireless metropolitan area network IEEE 802.16. New concepts are introduced that allow and further optimize the use of SDMA techniques brought by intelligent antennas. First, the possibility to enable SDMA in the IEEE 802.16a-2003 protocol is investigated, and second the support of SDMA in the revised 802.16-2004 standard is elaborated in detail. To overcome current limitations of 802.16a-2003, an enhanced control structure is introduced in 802.16-2004 that masters a concurrent transmission and reception of data to/from several different subscriber stations. The approach facilitates a fully flexible structure which significantly improves system capacity.
Christian P. Hoymann received his Diploma degree in electrical engineering from RWTH Aachen University in 2002. Before he served a student internship at SIEMENS Corporate Research, Princeton, USA. Since 2002 he is employed as a Research Assistant at the Chair of Communication Networks (ComNets) of RWTH Aachen University where he is working towards his Ph.D. degree.He worked in the fields of traffic engineering and dimensioning of GSM/GPRS networks together with his project partners at D2 Vodafone. He was actively involved in the IST-STRIKE project where smart antenna systems had been integrated in Metropolitan Area Networks. His current research interests include the optimization of MANs especially in consideration of smart antenna technologies such as SDMA and relaying technologies such as Mesh.Mr. Hoymann has published several conference and journal papers and was actively involved in the standardization of SDMA technologies for IEEE 802.16. 相似文献
987.
Green Melanie C.; Wheeler S. Christian; Hermann Anthony D.; Brock Timothy C. 《Canadian Metallurgical Quarterly》1998,53(9):1078b
Comments on D. Kipnis's (see record 199707781-001) article that critically analyzes social psychology's assumption that psychological states can explain social behavior. The present authors point out that there are many sources in social psychology that, in fact, have revealed a vibrant and rigorous discipline in which, contrary to Kipnis's "caricature," explanations are routinely empirically questioned, variables are directly manipulated and measured, often along with their physiological and neuro-electrical correlates, and multivariate approaches address the separate and joint impact of multiple predictors on multiple dependent variables. It is also noted that Kipnis ignored social psychological research in which experimenters have assessed the physiological correlates of cognitive states. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
988.
989.
This paper presents the acceleration of minimum-cost covering problems by instance-specific hardware. First, we formulate the minimum-cost covering problem and discuss a branch & bound algorithm to solve it. Then we describe instance-specific hardware architectures that implement branch & bound in 3-valued logic and use reduction techniques similar to those found in software solvers. We further present prototypical accelerator implementations and a corresponding design tool flow. Our experiments reveal significant raw speedups up to five orders of magnitude for a set of smaller unate covering problems. Provided that hardware compilation times can be reduced, we conclude that instance-specific acceleration of hard minimum-cost covering problems will lead to substantial overall speedups. 相似文献
990.