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991.
The cellular neural network (CNN) architecture combines the best features from traditional fully-connected analog neural networks and digital cellular automata. The network can rapidly process continuous-valued (gray-scale) input signals (such as images) and perform many computation functions which traditionally were implemented in digital form. Here, we briefly introduce the the theory of CNN circuits, provide some examples of CNN applications to image processing, and discuss work toward a CNN implementation in custom CMOS VLSI. The role of analog computer-aided design (CAD) will be briefly presented as it relates to analog neural network implementation.This work is supported in part by the Office of Naval Research under Contract N00014-89-J1402, and the National Science Foundation under grant MIP-8912639. 相似文献
992.
The results of observations performed over many years are used to make an assessment of the degree to which the concentration of chemical and radioactive substances escaping into the environment during salvaging of nuclear-powered submarines exceeds the admissable norms for workers at the main ship-repair facilities in Russia and for the general public in the surrounding territories. It is shown that the chemical substances are a determining factor in environmental contamination. Their content in the atmosphere and sea water exceeds the admissable norms near sources, on the territory of the enterprises, and (for individual indicators) at populated points. Under these conditions, the concentration of technogenic radionuclides does not exceed the admissable norms and its damaging effect on man is hundreds and thousands of times less than that of chemicals. 相似文献
993.
Yan R.-H. Lee K.F. Jeon D.Y. Kim Y.O. Park B.G. Pinto M.R. Rafferty C.S. Tennant D.M. Westerwick E.H. Chin G.M. Morris M.D. Early K. Mulgrew P. Mansfield W.M. Watts R.K. Voshchenkov A.M. Bokor J. Swartz R.G. Ourmazd A. 《Electron Device Letters, IEEE》1992,13(5):256-258
The authors report the implementation of deep-submicrometer Si MOSFETs that at room temperature have a unity-current-gain cutoff frequency (f T) of 89 GHz, for a drain-to-source bias of 1.5 V, a gate-to-source bias of 1 V, a gate oxide thickness of 40 Å, and a channel length of 0.15 μm. The fabrication procedure is mostly conventional, except for the e-beam defined gates. The speed performance is achieved through an intrinsic transit time of only 1.8 ps across the active device region 相似文献
994.
Rational algorithms for measuring the harmonic coefficient in microprocessor instruments for measuring nonlinear distortions based on digital processing of the codes of the instantaneous values of the signal being investigated are described and the errors of such instruments are obtained.Translated from Izmeritel'naya Tekhnika, No. 4, pp. 56–59, April, 1995. 相似文献
995.
S. V. Loginov 《Technical Physics Letters》2007,33(10):805-808
It is shown that the process of magnetic field penetration into the plasma bridge in a plasma opening switch is determined by the field diffusion near the magnetic piston, followed by the convective transport of magnetic field in the bridge. This transport is due to the field being “frozen in” to the flow of plasma behind the front of a shock wave, which is formed in the plasma accelerated by the magnetic field pressure. 相似文献
996.
997.
Propagation of Isothermal Flame in the Low-Pressure Thermal Decomposition of Nitrogen Trichloride 总被引:1,自引:0,他引:1
The inhibition and promotion of isothermal NCl3 flame by NOCl and H2, respectively, are explained. The crossover from the isothermal mode of flame propagation to the thermal one is analyzed for NCl3–He mixtures. Calculations based on a kinetic mechanism taking into account energy chain branching are performed, and qualitative agreement between the calculated and observed data is demonstrated. The one-dimensional problem of chain–thermal flame propagation by a chain reaction involving a nonlinear-branching step has two solutions corresponding, one corresponding the isothermal mode of flame propagation and the other corresponding to the chain–thermal one. Nonlinear chain branching shortens the time needed for thermal ignition and increases the flammability of the combustible mixture. 相似文献
998.
V. M. Piksaikin L. E. Kazakov G. G. Korolev S. G. Isaev V. A. Roshchenko M. Z. Tarasko 《Atomic Energy》2002,92(2):147-155
The relative yield of delayed neutrons and the half-life of their precursor nuclei in fissioning of 233U, 235U, and 239Pu by epithermal neutrons are measured on a setup which is based on a KG-2.5 electrostatic accelerator. The experimental samples are irradiated in a polyethylene cube, one face of which is irradiated by a neutron beam consisting of T(p, n)3He neutrons. A procedure is developed for averaging the group parameters of delayed neutrons from different series of measurements, taking account of their correlation. A comparative analysis of the data of this work and in ENDF/BVI in terms of the average half-life of the precursor nuclei of the delayed neutrons and using the dependence of the reactivity on the asymptotic period of the reactor is performed.It is shown that the data of this work agree, to within the uncertainty limits, with the recommended experimental data and differ substantially from the ENDF/BVI data. 相似文献
999.
V. Artisyuk M. Saito A. Stankovskii Yu. Korovin A. Shmelev 《Progress in Nuclear Energy》2002,40(3-4):637-645
The present paper focuses on analysis of radiological hazard of spallation products that appears to be an important factor that might affect the choice of beam/target performance in designing the accelerator-driven systems. The analysis is done in terms of toxicity expressed in units of Annual Limit on Intake (ALI). It reveals the significant contribution of alpha emitting rare earths (146Sm, 148Gd, 150Gd, 154Dy) into overall toxicity of spallation targets. 相似文献
1000.
G.P. Berman G.D. DoolenG.V. López V.I. Tsifrinovich 《Computer Physics Communications》2002,146(3):324-330
We demonstrate a strategy for implementation a quantum full adder in a spin chain quantum computer. As an example, we simulate a quantum full adder in a chain containing 201 spins. Our simulations also demonstrate how one can minimize errors generated by non-resonant effects. 相似文献