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31.
Bellare M. Garay J.A. Hauser R. Herzberg A. Krawczyk H. Steiner M. Tsudik G. Van Herreweghen E. Waidner M. 《Selected Areas in Communications, IEEE Journal on》2000,18(4):611-627
This paper discusses the design, implementation, and deployment of a secure and practical payment system for electronic commerce on the Internet. The system is based on the iKP family of protocols-(i=1,2,3)-developed at IBM Research. The protocols implement credit card-based transactions between buyers and merchants while the existing financial network is used for payment clearing and authorization. The protocols are extensible and can be readily applied to other account-based payment models, such as debit cards. They are based on careful and minimal use of public-key cryptography, and can be implemented in either software or hardware. Individual protocols differ in both complexity and degree of security. In addition to being both a precursor and a direct ancestor of the well-known SET standard, iKP-based payment systems have been in continuous operation on the Internet since mid-1996. This longevity-as well as the security and relative simplicity of the underlying mechanisms-makes the iKP experience unique. For this reason, this paper also reports on, and addresses, a number of practical issues arising in the course of implementation and real-world deployment of a secure payment system 相似文献
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Martti Heinonen Miltiadis Anagnostou Stephanie Bell Mark Stevens Robert Benyon Reidun Anita Bergerud Jovan Bojkovski Rien Bosma Jan Nielsen Norbert B?se Plunkett Cromwell Aliye Kartal Dogan Seda Aytekin Ali Uytun Vito Fernicola Krzysztof Flakiewicz Bertrand Blanquart Domen Hudoklin Per Jacobson Anders Kentved Isabel Lóio George Mamontov Alexandra Masarykova Helmut Mitter Regina Mnguni Jan Otych Anton Steiner Nagyné Szilágyi Zsófia Davor Zvizdic 《International Journal of Thermophysics》2012,33(8-9):1422-1437
In the field of humidity quantities, the first CIPM key comparison, CCT-K6 is at its end. The corresponding European regional key comparison, EUROMET.T-K6, was completed in early 2008, about 4?years after the starting initial measurements in the project. In total, 24 NMIs from different countries took part in the comparison. This number includes 22 EURAMET countries, and Russia and South Africa. The comparison covered the dew-point temperature range from ?50?°C to +20?°C. It was carried out in three parallel loops, each with two chilled mirror hygrometers as transfer standards in each loop. The comparison scheme was designed to ensure high quality results with evenly spread workload for the participants. It is shown that the standard uncertainty due to the long-term instability was smaller than 0.008?°C in all loops. The standard uncertainties due to links between the loops were found to be smaller than 0.025?°C at ?50?°C and 0.010?°C elsewhere. Conclusions on the equivalence of the dew-point temperature standards are drawn on the basis of calculated bilateral degrees of equivalence and deviations from the EURAMET comparison reference values (ERV). Taking into account 16 different primary dew-point realizations and 8 secondary realizations, the results demonstrate the equivalence of a large number of laboratories at an uncertainty level that is better than achieved in other multilateral comparisons so far in the humidity field. 相似文献
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通过调查得知,包括虚拟现实技术在机床制造中应用可能性的应用方法、策略和工具在产品开发中的现状.对调查结果进行了讨论,考虑到研究理论的可移植性和对企业内部实战的依赖性.讨论的结果为基础研究领域的命题"基于职能单位的产品开发"提供结论. 相似文献
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Dorian Zapp Judith Scheiber Oliver Gerner Edith Fuchs Jakub Dvorak Daniel Mayer Matthias Nemestothy Rupert Steiner 《世界建筑导报》2018,(3)
正科帕卡格拉纳位于新多瑙河12.5公里处,毗邻Reichsbrücke大桥。出于同旧有设计保持协调性考虑,力求能让大楼融入当地环境,迎合自身功能性需要,GERNER GERNER PLUS团队充分考虑现有周边环境,对大楼重新规划设计。新的设计突显建筑的特殊性和重要性,面向河流的立面是科帕卡格拉纳大楼最重要的部分,所以设计的重点也放在了这里。现有的城市中轴线是一个参照物,为了视觉上和氛围上形成一体化城市的感 相似文献
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S. Herweg F. Huber S. Atamer R. Steiner R. Weller B. Sauer S. Wiesker M. Mármol Fernández 《Forschung im Ingenieurwesen》2018,82(4):273-283
As part of a cooperation project, Daimler AG and the Institute of Machine Elements, Gears, and Transmissions (MEGT) at the Technische Universität Kaiserslautern are carrying out detailed investigations on a valve train with roller lever. The aim of the project is to develop a detailed simulation method that allows the secondary movement of the valve train to be modeled and thus represents an extension of the classic valve train dynamics simulation. This opens up the opportunity to evaluate the processes within the valve train in detail in the early stages of the product development process. This report introduces the validation of the methodology based on experimental results. First, the focus is placed on the cam-roller contact, which induces the secondary movement of the valve train. This movement takes place in the axial direction of the camshaft so that the validation takes place on the basis of the measured force in this direction. The force is dependent on the load, i.?e. the combination of speed and normal force, as well as the angular misalignments between cam and roller. Following the validation of the detailed modeling of the cam-roller contact, the gained knowledge is transferred into the extended valve train simulations. Finally the valve train simulation is validated. 相似文献
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Forschung im Ingenieurwesen - Die mechanischen Verluste von Verbrennungsmotoren hängen maßgeblich von den auftretenden Reibkräften innerhalb der Kolbengruppe ab. Da die Kolbengruppe... 相似文献
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