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991.
Analysis and synthesis of on-chip spiral inductors 总被引:3,自引:0,他引:3
This paper presents a physically based compact model for estimating high-frequency performance of spiral inductors. The model accurately accounts for skin and proximity effects in the metal conductors as well as eddy current losses in the substrate. The model shows excellent agreement with measured data mostly within 10% across a variety of inductor geometries and substrate dopings up to 20 GHz. A web-based spiral inductor synthesis and analysis tool COILS, which makes use of the compact models, is presented. An optimization algorithm using binary searches speeds up the synthesis of inductor designs. 相似文献
992.
J.H. Kaneko T. Tanaka S. Kawamura Y. Oshiki K. Tsuji M. Katagiri K. Ochiai T. Nishitani F. Fujita A. Homma T. Sawamura T. Iida M. Furusaka 《Diamond and Related Materials》2005,14(11-12):2027
Radiation detector was made of a high-quality CVD polycrystalline diamond composed of frost column like structure diamond grains, and induced charge distribution spectra and drift velocities were measured by using alpha particles. As a result, the CVD polycrystalline achieved maximum induced charge of 83% of HP/HT type IIa diamond. Moreover, the CVD crystal had lower charge loss on electrons compared with the HP/HT type IIa diamond. Drift velocities of electrons and holes were ve = 7.7 × 104 and vh = 7.3 × 104cm/s at an electric field of 20 kV/cm, respectively. In addition, response function measurement for 14 MeV neutrons was carried out. 相似文献
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The problem of residence-time control by the observer-based output feedback is formulated and solved for the case of linear systems with small additive input noise. Both noiseless and noisy measurements are considered. In the noiseless measurements case, it is shown that the fundamental bounds on the achievable residence time depend on the nonminimum phase zeros of the system. In the noisy measurements case, the achievable residence time is shown to be always bounded, and an estimate of this bound is given. Controller design techniques are presented. The development is based on the asymptotic large deviations theory.
Recommended by T K. Caughey 相似文献
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A method for assessing the differential risk of failure among a system's modules is proposed. The procedure has three components: external-risk assessment, module exposure, and module-failure likelihood. External-risk assessment is a consideration of the system's environment, almost independent of the software's details. To estimate module exposure, the model relates individual modules and their potential faults to the external-failure modes and their economic consequences by reverse-engineering the specifications and analyzing each module's expected use. To estimate failure likelihood, the method uses a reliability model. The method constitutes theoretical foundation for the cost-effective development of software that attempts to reduce the risk of failure. Managers can use the failure-risk estimates to better determine how much testing effort can be economically justified 相似文献
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