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971.
Sure System 2000, a fault-tolerant computer that couples multiprocessors to offer low-priced, high-performance systems that deal effectively with faults and failures, is presented. The architecture is based on the local redundancy technique, ensuring that no hardware or software fault can cause a system crash. Software errors can be fixed, and hardware can be replaced, upgraded, or added dynamically. Existing fault-tolerant computers are briefly reviewed, and the logic hardware system configuration of the Sure System 2000 is described. The multiprocessor and I/O architecture are examined. The SXO Sure System 2000 expandable operating system is described 相似文献
972.
973.
A coupled-mode theory of overmoded, cylindrical metal Bragg-reflectors is presented. The first-order Bragg coupling constants are derived for TE → TE, TM → TM, TE → TM, and TM → TE mode conversions. Reflectivities and transverse modeQ -factors are computed for a Bragg-reflector resonator. The results illustrate important competition effects between nearly-degenerate-transverse-modes occurring within both the Bragg-reflectors and the resonator. 相似文献
974.
Z. P. Shul'man B. M. Khusid I. L. Ryklina É. A. Zal'tsgendler O. R. Dornyak É. V. Ivashkevich Z. A. Shabunina 《Journal of Engineering Physics and Thermophysics》1987,53(5):1285-1291
Dynamic processes are studied in media with softly and hardly internal destroyable configurations. A method is examined for the measurement of properties of media with spatial separation of the chemical transformation stages and thermal hydrodynamic measurements.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 53, No. 5, pp. 781–789, November, 1987. 相似文献
975.
976.
A. Bernasik J. Janowski W. Hirschwald F. Stolze J. Nowotny 《Journal of Materials Science》1991,26(9):2527-2532
Surface segregation of various impurities such as Mg, Si, Ca, Al and Cr were determined for the haematite phase (Fe2O3) annealed in two different gas compositions involving (1) air at 1173 K, and (2) a gas mixture containing sulphur at 773 K. The objective of work was to establish the effect of the gas-phase composition on segregation of lattice defects. The near-surface segregation profiles of the impurities were determined by secondary ion mass spectrometry. The depth profile analysis was made by sputtering using an Ar+ primary beam of energy 30 keV. The surface charge was neutralized by an electron gun. It was found that annealing Fe2O3 under a gas phase containing sulphur resulted in the formation of an Fe(SO4)3 surface layer. It was observed that the two surface treatment procedures applied (both with and without sulphur) result in Mg enrichment in the near-surface region of Fe2O3. Si and Ca exhibit an enrichment and impoverishment after the surface treatments 1 and 2, respectively. Finally, the near-surface layer is impoverished in Cr and Al after both types of surface treatment. Experimental results are discussed in terms of segregation driving forces of the respective elements and the possible effect of sulphur on the gas-solid heterogeneous kinetics. 相似文献
977.
Y. Rey-Tauriac J. Badoc B. Reynard R.A. Bianchi D. Lachenal A. Bravaix 《Microelectronics Reliability》2005,45(9-11):1349
This paper presents results of reliability investigation of 20 V N-Drift MOS transistor in 0.13 μm CMOS technology. Due to high performances required for CMOS applications, adding high voltage devices becomes a big challenge to guarantee the reliability criteria. In this context, new reliability approaches are needed. Safe Operating Area are defined for switch, Vds limited and Vgs limited applications in order to improve circuit designs. For Vds limited applications, deep doping dose effects in drift area are investigated in correlation to lifetime evaluations based on device parameter shifts under hot carrier stressing. To further determine the amount and locations of hot carriers injections, accurate 2D technological and electrical simulations are performed and permit to select the best compromise between performance and reliability for N-Drift MOS transistor. 相似文献
978.
N. V. Vostokov Yu. N. Drozdov Z. F. Krasil’nik O. A. Kuznetsov A. V. Novikov V. A. Perevoshchikov M. V. Shaleev 《Russian Microelectronics》2005,34(4):203-209
The results are presented of the fabrication of strain-relaxed graded Si1 − x
Gex/Si(001) buffer layers with a maximum Ge fraction of about 0.25 that have a low density of threading dislocations (<106 cm−2) and low surface roughness. The buffer layers are grown by atmospheric-pressure hydride CVD. It is found that chemical mechanical polishing can reduce their surface roughness to a level comparable with that of the original Si(001) substrates. It is shown that the polished buffer layers can serve as substrates for MBE-grown SiGe/Si heterostructures.__________Translated from Mikroelektronika, Vol. 34, No. 4, 2005, pp. 243–250.Original Russian Text Copyright © 2005 by Vostokov, Drozdov, Krasil’nik, Kuznetsov, Novikov, Perevoshchikov, Shaleev. 相似文献
979.
This paper proposes a new control algorithm for a linear belt-driven servomechanism. The elasticity of the belt and large nonlinear friction along with large variation of parameters limit the applicability of the belt driven servosystems. Design of simple control that can guarantee stable, vibration-free operation for large variation of load is needed to extend application of such a linear stage. The proposed control is based on the application of sliding mode methods combined with Lyapunov design so it guarantees the stability of the system. Due to the restriction of the system motion to specially selected sliding mode manifold the vibration free position tracking is achieved with very good disturbance rejection. Proposed algorithm is simple and practical for an implementation and the tuning procedure of the control parameters is simple. The experiments have shown that the proposed control scheme effectively suppresses vibrations and assures wide closed-loop bandwidth for position tracking control. 相似文献
980.