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51.
A new class of non-canonic, driving-point immittance realizations of passive, common-ground, transformerless, two-element-kind RLC networks with minimum number of nodes is presented. Six new algorithms of realization are developed by application of canonic, orthogonal matrix transformations with reduced number of degrees of freedom. the number of applied RLC elements of one kind can be minimized and of the other kind reduced, while their parameter values are calculated directly in a linear way.  相似文献   
52.
Abstract— A passively addressed 64 × 64 ferroelectric liquid‐crystal display (FLCD) has been developed. The display matrix has a 33 × 33 mm2 aperture, and the FLC layer thickness is 5.2 ± 0.2 μm. The display device operates with a frame frequency of 30 Hz (at Vrow = ±18 V, Vcol = ±9 V, T = 23°C), generating a continuous gray scale which can be memorized for more than 10 days after the driving voltage is switched off. A new approach for multiplex electronic addressing of the FLCD gray scale is proposed. The conditions of the hysteresis‐free gray‐scale generation for multiplex addressing and the gray‐scale memorization after the voltage is switched off, as well as the time steadiness of memorized images, are considered.  相似文献   
53.
The effect of γ-ray photons and electron beams on electroluminescence of the ZnS:(Cu, Br) and ZnS:(Cu, Al, Br) phosphors is studied. Irradiation of both samples with γ-ray photons and of the ZnS(Cu, Br) sample with electrons makes it possible to increase the emission intensity by 20–35% at the optimal radiation dose of 5–10 Mrad. In this case, the relative intensity of the green-emission band increases in the electroluminescence spectra of all samples, presumably due to dissociation of the CuI-CuZn and BrZn-V Zn donor-acceptor pairs. Thus, irradiation makes it possible to control the intensity and spectrum of phosphors’ emission, which can be used for nonchemical lithography of luminescent layers.  相似文献   
54.
A Genetic Programming Approach to Rainfall-Runoff Modelling   总被引:2,自引:1,他引:1  
Planning for sustainable development of water resources relies crucially on the data available. Continuous hydrologic simulation based on conceptual models has proved to be the appropriate tool for studying rainfall-runoff processes and for providing necessary data. In recent years, artificial neural networks have emerged as a novel identification technique for the modelling of hydrological processes. However, they represent their knowledge in terms of a weight matrix that is not accessible to human understanding at present. This paper introduces genetic programming, which is an evolutionary computing method that provides a transparent and structured system identification, to rainfall-runoff modelling. The genetic-programming approach is applied to flow prediction for the Kirkton catchment in Scotland (U.K.). The results obtained are compared to those attained using two optimally calibrated conceptual models and an artificial neural network. Correlations identified using data-driven approaches (genetic programming and neural network) are surprising in their consistency considering the relative size of the models and the number of variables included. These results also compare favourably with the conceptual models.  相似文献   
55.
Based on results of measurement and processing of volt-ampere characteristics as well as linetic modeling of electron transfer by the Monte Carlo method, the influence of the doping level and the temperature on electron mobility in the n channel of a silicon MOS field-effect transistor operating in a linear regime is investigated. Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 71, No. 1, pp. 116–119, January–February, 1998.  相似文献   
56.
Results are presented of an experimental investigation of the effect of the temperature factor on the law of heat transfer in turbulent boundary layers.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 19, No.2, pp. 185–189, August, 1970.  相似文献   
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Renewal type bootstrap for Markov chains   总被引:1,自引:1,他引:0  
In this paper we treat a renewal type of bootstrap for atomic Markov chains under minimal moment conditions on renewal times, i.e.Er 2<∞. Three main results are: a) if a Markov chain satisfies the CLT for the mean then it also satisfies a bootstrap CLT; b) if a Markov chain satisfies a uniform CLT over classes of functions then, it also satisfies bootstrap uniform CLT with minimal condition on envelope functionF; c) we establish second order correctness for this procedure. All results are for “in probability” bootstrap and constitute the final word in this setting.  相似文献   
60.
Silicon layers of 150 nm thickness supersaturated with indium up to ≈5 at% were prepared by multiple energy ion implantation. A redistribution of the implanted impurities caused by post-implantation annealing and following irradiation with swift Bi ions has been observed by means of Rutherford backscattering spectrometry in channelling configuration (RBS/C). It is demonstrated by TEM that the thermal decomposition of the supersaturated Si〈In〉 solution is accompanied by polycrystalline recrystallisation of amorphous silicon, precipitation of the second phase (In) both within the implanted layer and on the surface, as well as by impurity redistribution. The main features of the structure transformation under the influence of the Bi ion irradiation are discussed.  相似文献   
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