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971.
Sarto M.S. Voti R.L. Sarto F. Larciprete M.C. 《Electromagnetic Compatibility, IEEE Transactions on》2005,47(3):602-611
New nanolayered coatings are designed and deposited on flexible plastic substrate having the thickness of 100 /spl mu/m, in order to realize lightweight ultrathin transparent shielding foils. The structure of the coating is optimized considering three figures of merit: the average transmittance in the visible range for normal incidence, the normalized average transmittance for oblique incidence at 550 nm, and the transmittance quality factor. The nanotechnology exploited for the deposition of the transparent metals is the dual ion beam sputtering. Tests of durability, optical transmission, and shielding effectiveness demonstrate that the film has a high adhesion under mechanical solicitation, high resistance against aging, peak transmittance in the visible range higher than 70%, omnidirectional properties in the range 0/spl deg/-60/spl deg/, and shielding effectiveness of 40 dB up to 6 GHz. 相似文献
972.
A strong motivation for insertion of optical interconnects in short-distance applications such as chip-to-chip or back-plane communication, apart from high bit rates, is their potential to achieve these bit rates at low power compared to the currently prevalent copper based interconnects. Thus, it is imperative to construct design methodologies which minimize the total optical link power dissipation. We present one such methodology, where we optimize the quantum-well modulators to minimize the power dissipation in modulator-based optical interconnects. In the first part of the paper, the focus is on obtaining the optimal modulator metrics [contrast ration (CR) and insertion loss], which yield the lowest total power (receiver and the modulator). The trends are studied as a function of the input laser power and bit rate. Having obtained the desirable modulator metrics and the corresponding power dissipation, in the second part, the focus is on the feasibility of these metrics in the light of voltage swing constraints. The biggest concern with the modulator based optical link is the low CR, especially at low voltage swing. While studying these concerns, we also provide insight into the physical design of the modulator including, its intrinsic region thickness, pre-bias voltage, and the size and the number of quantum-wells. Specifically, we outline the method to obtain the design parameters, which allows minimum power dissipation with the least laser power. This ultimately yields higher aggregate I/O bandwidth for chip to chip communication in power limited chips. 相似文献
973.
Cogburn D.L. Mueller M. McKnight L. Klein H. Mathiason J. 《Communications Magazine, IEEE》2005,43(12):12-14
Who should control the Internet? A dozen years after the Internet became a mass medium, this issue has continued to grow in urgency, becoming white hot in fall 2005. At the September 2005 preparatory meeting for the UN World Summit on the Information Society (WSIS), a coalition of countries criticized the United States' unilateral control of the Internet's domain name system (DNS) and proposed the establishment of a multinational Council to supervise it. This proposal emerged from the Final Report of the UN Working Group on Internet Governance. Researchers from the Internet Governance Project, a university-based consortium for policy analysis, have concluded that the United States should internationalize governance of the Internet, but in a way that avoids intrusive, centralized control. 相似文献
974.
Yamaoka M. Shinozaki Y. Maeda N. Shimazaki Y. Kato K. Shimada S. Yanagisawa K. Osada K. 《Solid-State Circuits, IEEE Journal of》2005,40(1):186-194
An on-chip 1-Mb SRAM suitable for embedding in the application processor used in mobile cellular phones was developed. This SRAM supports three operating modes - high-speed active mode, low-leakage low-speed active mode, and standby mode - and uses a subdivisional power-line control (SPC) scheme. The combination of three operating modes and the SPC scheme realizes low-power operation under actual usage conditions. It operates at 300 MHz, with leakage of 25 /spl mu/A/Mb in standby mode, and 50 /spl mu/A/Mb at the low-leakage active mode. This SRAM also uses a self-bias write scheme that decreases of minimum operating voltage by about 100 mV. 相似文献
975.
Nietzel Michael T.; Russell Robert L.; Hemmings Kelly A.; Gretter Monica L. 《Canadian Metallurgical Quarterly》1987,55(2):156
[Correction Notice: An erratum for this article was reported in Vol 55(3) of Journal of Consulting and Clinical Psychology (see record 2008-10745-001). The data presented in Table 2 were incorrect because a row and a column were inadvertently omitted. The corrected Table 2 appears in the erratum.] This study used meta-analysis to study the clinical significance of psychotherapy for symptoms of unipolar depression. The following questions were addressed: How similar is the posttherapy adjustment of depressed adults to that of nondepressed adults? Is this adjustment maintained at follow-up? What dimensions of treatment, therapists, or design are associated with clinical significance? Using the Beck Depression Inventory (BDI), we calculated composite BDI norms from 28 published studies. Sixty effect sizes (from 31 outcome studies utilizing the BDI) were calculated. The results indicated that psychotherapy produces outcomes that have moderate clinical significance and that are well-maintained at follow-up, that individual therapy is associated with greater clinical significance than group treatment, and that type of therapy is not related to improvement. Alternative approaches for operationalizing clinical significance as the return of individuals to normal levels of functioning are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
976.
977.
978.
We analyze the impact of gate electrode thickness and gate underlap on the fringe capacitance of nanoscale double-gate MOS (DGMOS) transistors. We propose an analytical fringe capacitance model considering gate underlap and finite source/drain length. A comparison with the simulation results show that the model can accurately estimate the fringe capacitance of the device. We show that an optimum gate underlap can significantly reduce the fringe capacitance resulting in higher performance and lower power consumption. Also, the effects of process variation in gate underlap devices are discussed. Simulation results on a three-stage ring oscillator show that with optimum gate underlap 32% improvement in delay can be achieved. 相似文献
979.
Self-Adapting Linear Algebra Algorithms and Software 总被引:2,自引:0,他引:2
Demmel J. Dongarra J. Eijkhout V. Fuentes E. Petitet A. Vuduc R. Whaley R.C. Yelick K. 《Proceedings of the IEEE. Institute of Electrical and Electronics Engineers》2005,93(2):293-312
One of the main obstacles to the efficient solution of scientific problems is the problem of tuning software, both to the available architecture and to the user problem at hand. We describe approaches for obtaining tuned high-performance kernels and for automatically choosing suitable algorithms. Specifically, we describe the generation of dense and sparse Basic Linear Algebra Subprograms (BLAS) kernels, and the selection of linear solver algorithms. However, the ideas presented here extend beyond these areas, which can be considered proof of concept. 相似文献
980.
The article established the regularities of change of the physicomechanical characteristics and strength of glass textolites in single and repeated thermal loading. It shows that under multiple loading the intense loss of strength of the investigated materials is due to increased porosity on account of the large number of microcracks appearing in the structure. A correlation is obtained between the elastic and strength characteristics and porosity in dependence on the temperature of multiple heating which in the first approximation is described by a polynomial of second degree with respect to temperature, multiplied by the reciprocal of porosity.Translated from Problemy Prochnosti, No. 6, pp. 53–58, June, 1991. 相似文献