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701.
Rosen A. Stabile P.J. Gombar A.M. Janton W.M. Bahasadri A. Herczfeld P. 《Photonics Technology Letters, IEEE》1989,1(6):132-134
A two-dimensional laser array, delivering a peak power of 1 kW with an overall efficiency of 33%, was used to activate silicon p-i-n diodes. A single device, activated by a 1 kW laser, produced a holding voltage of 1000 V and conducted 56 A. When two similar p-i-n diodes were connected in parallel and activated by two 1 kW AlGaAs laser arrays, a holding voltage of 1000 V and conduction of 100 A were obtained 相似文献
702.
An analog front-end chip fabricated in a 4-μm CMOS process has been described. The chip, together with a digital signal processor, implements a full-duplex transceiver for twisted pairs. A fully differential architecture has been used in all the analog signal-processing blocks to get high dynamic range and common-mode noise rejection. The front-end output is a 12-b word generated by a 6-μs A/D (analog-to-digital) converter with autocalibration, with a linearity better than 1 LSB 相似文献
703.
Kryazhimskiy A. V. Maksimov V. I. 《Proceedings of the Steklov Institute of Mathematics》2006,253(1):S168-S184
A problem of guaranteeing control for a system of parabolic equations is considered. A solving algorithm based on the combination of real time reconstruction processes and feedback control is designed. 相似文献
704.
N. A. Lockerbie 《General Relativity and Gravitation》2006,38(3):533-536
This paper is in answer to the comment on the GRG paper: Lockerbie N.A. Gen. Rel. Grav. 36, 593 (2004), made by A.V. Sanders, G.T. Gillies (ibid.).
N. A. Lockerbie is a member of the STEP (Satellite Test of the Equivalence Principle) Science Study Team, and an Associate
of the Institute for Gravitational Research at the University of Glasgow, Scotland, UK. 相似文献
705.
706.
The spectra of the intensity fluctuations of light scattered by large (erythrocytes of whole blood) and small (vesicles of surgical bile) particles in natural conditions were studied. It is shown that photon correlation spectroscopy can be used in analysis of variations in the size of biological particles in normal and pathological conditions and as an express method of noninvasive diagnostics of diseases. 相似文献
707.
Vectored transmission for digital subscriber line systems 总被引:2,自引:0,他引:2
This paper describes the "vectored" transmission technique for digital subscriber line (DSL) systems, which utilizes user coordination at the central office or optical network unit. This method exploits the colocation of the downstream transmitters and of the upstream receivers, in order to achieve far-end crosstalk (FEXT) cancellation and perform multiuser transmission optimization. The performance improvements are particularly pronounced in environments with strong FEXT such as in very high-speed DSL. Discrete multitone is employed for each user with additional constraints on the cyclic prefix length and with the assumption of block-synchronized transmission and reception for downstream and upstream transmission correspondingly. Within each tone, upstream crosstalk is removed by multiple-input-multiple-output decision feedback at the receiving side, while downstream crosstalk is eliminated by analogous preprocessing at the transmitting side. Additionally, the issue of transmission energy allocation in frequency and among users is addressed. Assuming frequency-division duplexing, the corresponding optimization problem is formulated and solved via convex programming both for a fixed upstream-downstream band plan and for a dynamically programmable band plan. The case of power backoff as a means to reduce the impact of crosstalk on alien systems is also treated. Interestingly, the performance of the proposed methods is shown to be very close to known information theory bounds 相似文献
708.
A. V. Räisänen W. R. McGrath D. G. Crete P. L. Richards 《Journal of Infrared, Millimeter and Terahertz Waves》1985,6(12):1169-1189
Several scaled models have been used to determine the contributions of various waveguide mount parameters to the embedding impedance of a mm-wave SIS mixer. Measured effects of waveguide height, substrate orientation and width, junction location, lead inductance and RF-filter impedance are presented and discussed. 相似文献
709.
S. E. Bogushevich V. N. Makatun A. K. Potapovich I. I. Ugolev 《Journal of Applied Spectroscopy》1991,55(4):1016-1020
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 55, No. 4, pp. 613–618, October, 1991. 相似文献
710.
S. A. Logvinenko I. N. Timoshina Yu. V. Moseev 《Journal of Mathematical Sciences》1991,57(5):3361-3366
Modifications are introduced into the large-particle method to make it possible to use the method in arbitrary nonrectangular computing nets in the study of the flow of an ideal compressible gas over mobile thin permeable membranes. A problem in the aeroelasticity of a parachute is stated. An example is given of the solution of a problem in the stationary formulation for an axially symmetric parachute in the wake of a cylindrical leading body for supersonic flow.Translated fromDinamicheskie Sistemy, No. 6, 1987, pp. 16–22 相似文献