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991.
Lasers containing a nanopatterned active layer demonstrating excellent threshold characteristics are presented. The nanopatterned active layer is fabricated using high-resolution electron beam lithography and selective-area metal organic chemical vapour deposition crystal growth. Results demonstrating an order of magnitude improvement over previous results are reported. 相似文献
992.
Low-voltage wideband compact CMOS variable gain amplifier 总被引:1,自引:0,他引:1
A novel low-voltage wideband CMOS variable gain amplifier (VGA) is proposed. Using a 0.13 /spl mu/m CMOS technology, the VGA exhibits a linear-dB controllable gain range of 40 dB with a bandwidth in excess of 130 MHz, while drawing only 50 /spl mu/A from a single 1 V power supply voltage. 相似文献
993.
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
994.
995.
996.
A. Neubauer 《Computing》1987,39(1):43-55
We discuss the numerical realization of an a-posteriori parameter choice for Tikhonov regularization of linear integral equations of the first kind in Hilbert scales that leads to optimal convergence rates and that does not need any information about the exact solution. Numerical examples confirm the theoretical results. 相似文献
997.
Lifang Li Jindal N. Goldsmith A. 《IEEE transactions on information theory / Professional Technical Group on Information Theory》2005,51(4):1326-1347
We derive the outage capacity region of an M-user fading multiple-access channel (MAC) under the assumption that both the transmitters and the receiver have perfect channel side information (CSI). The outage capacity region is implicitly obtained by deriving the outage probability region for a given rate vector. Given a required rate and average power constraint for each user, we find a successive decoding strategy and a power allocation policy that achieves points on the boundary of the outage probability region. We discuss the scenario where an outage must be declared simultaneously for all users (common outage) and when outages can be declared individually (individual outage) for each user. 相似文献
998.
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
999.
1000.