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971.
RFID技术应用前景 总被引:5,自引:0,他引:5
何阿毜 《信息技术与标准化》2006,(1):23-26
介绍了RFID系统的组成、工作原理和特点,着重阐述RFID技术在各个领域的应用和在推广应用中存在的问题。最后论述了RFID的应用前景。 相似文献
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Feng HuangAuthor Vitae Xubang ShenAuthor VitaeXuecheng ZouAuthor Vitae Chaoyang ChenAuthor Vitae 《Microelectronics Journal》2003,34(1):85-91
This paper presents improvements in generation of wideband and high dynamic range analog signal for area-efficient MADBIST, especially for the on-chip testing of wireless communication IF digitizing sigma-delta modulator chip. Via increasing the order of the one-bit bandpass sigma-delta modulation algorithm up to 12 and using finite repetitious bitstream approximating scheme, it can achieve great improvements in signal bandwidth instead of purity at the cost of very little hardware overhead. Another contribution in this work is to provide the theoretical analysis of the reconstructed signal degradation due to harmonic distortion and clock jitter. Such on-chip analog stimulus generation scheme is especially fit for IF digitizing bandpass sigma-delta modulator chip's production-time testing and in-the-field diagnostics. The technique can also be extended to mixed-signal communication SoC built-in-self-test. 相似文献
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In standard portfolio theory, an investor is typically taken as having one stochastic objective, to maximize the random variable
of portfolio return. But in this paper, we focus on investors whose purpose is to build, more broadly, a “suitable portfolio”
taking additional concerns into account. Such investors would have additional stochastic and deterministic objectives that
might include liquidity, dividends, number of securities in a portfolio, social responsibility, and so forth. To accommodate
such investors, we develop a multiple criteria portfolio selection formulation, corroborate its appropriateness by examining
the sensitivity of the nondominated frontier to various factors, and observe the conversion of the nondominated frontier to a nondominated surface. Furthermore, multiple criteria enable us to provide an explanation as to why the “market portfolio,” so often found deep
below the nondominated frontier, is roughly where one would expect it to be with multiple criteria. After commenting on solvability
issues, the paper concludes with the idea that what is the “modern portfolio theory” of today might well be interpreted as
a projection onto two-space of a real multiple criteria portfolio selection problem from higher dimensional space.
M. Hirschberger: Research conducted while a Visiting Scholar at the Department of Banking and Finance, Terry College of Business,
University of Georgia, October 2003–March 2004. 相似文献
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This tutorial article introduces the physics of spin transfer torques in magnetic devices. Our intention is that it be accessible to beginning graduate students. We provide an elementary discussion of the mechanism of spin transfer torque and review the theoretical and experimental progress in this field. This article is meant to set the stage for the articles which follow in this volume of the Journal of Magnetism and Magnetic Materials, which focus in more depth on particularly interesting aspects of spin-torque physics and highlight unanswered questions that might be productive topics for future research. 相似文献
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Ralph Puchta Bernhard Roling Andreas Scheurer Verena Weiskopf Frank Hampel Nico J.R. van Eikema Hommes Hans-Ulrich Hummel 《Solid State Ionics》2008,179(13-14):489-494
Polycrystalline bicyclic diironcryptates with different mobile guest cations were synthesized and characterized by XRD analysis, IR spectroscopy, FAB-mass spectroscopy, elemental analysis, electrical conductivity spectroscopy and ion exchange experiments. We find strong indication that the guest cations exhibit a long-range mobility and that their mobility is governed by their size relative to the size of the cryptand molecules. On the other hand, the valence of the guest cations seems to play a minor role for the mobility. These results are discussed in comparison to the properties of conventional solid cationic conductors. 相似文献