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61.
Some remarks to problems of point and interval estimation, testing and problems of outliers are presented in the case of multivariate regression model. This work was supported by the Council of Czech Government J14/98:153100011.  相似文献   
62.
The influence of processing parameters on the electrical characteristics of RuO2/LaAlO3/Si metal-oxide-semiconductor structures was investigated. In particular, the sputtering regime during deposition of LaAlO3 on Si and the atmosphere used in the post-deposition annealing step were addressed by determining capacitance-voltage and gate current-voltage characteristics. These results were correlated with compositional information obtained by Rutherford backscattering spectrometry and nuclear reaction analysis. A post-deposition annealing step in oxygen at 600 °C resulted in better electrical characteristics of the final structure as compared to the same treatment performed in nitrogen. This result is explained by oxygen ability to heal oxygen vacancies in the LaAlO3 film, especially at the dielectric/semiconductor interface region. A thermalized sputtering regime during deposition of LaAlO3 on Si leads to capacitors with electrical characteristics superior to those deposited in ballistic regime. PACS 77.84.Dy; 81.15.Cd; 81.40.Gh; 73.40.Qv; 82.80.Yc  相似文献   
63.
Problems related to Tutte’s theorem on the generation of the cycle space of a 3-connected finite graph are discussed for infinite graphs.  相似文献   
64.
By using the method of generalized conjugation problems, we propose a numerical scheme for investigation of the redistribution of temperature stresses in a piecewise-homogeneous cylindrical shell caused by a longitudinal crack. This scheme is based on systems of integral equations (some of them are singular) to determine the unknown jumps of integral characteristics of the disturbed temperature field and displacements and their derivatives on the line of a crack and on the interface as well as the derivatives of these integral characteristics with respect to the longitudinal coordinate at the interface.  相似文献   
65.
In this work we study the solution of Laplace's equation in a domain with holes by an iteration consisting of splitting the problem in an exterior one, around the holes, plus an interior problem in the unholed domain. We show the existence of a decomposition of the solution when the exterior problem is represented by means of a single-layer protential. Also, for the three-dimensional case and with some adjustments for the two-dimensional case, we prove convergence of the method by writing the iteration as a Jacobi iteration for an operator equation and studying the spectrum of the iteration operator. To cite this article: R. Celorrio et al., C. R. Acad. Sci. Paris, Ser. I 334 (2002) 923–926.  相似文献   
66.
67.
The adsorption of hydrogen on a clean Cu10%/Ni90% (110) alloy single crystal was studied using flash desorption spectroscopy (FDS), Auger electron spectroscopy (AES), and work function measurements. Surface compositions were varied from 100% Ni to 35% Ni. The hydrogen chemisorption on a-surface of 100% nickel revealed strong attractive interactions between the hydrogen atoms in accordance with previous work on Ni(100). Three desorption states (β1, β2 and α) appeared in the desorption spectra. The highest temperature (α) state was occupied only after the initial population of the β2-state. As the amount of copper was increased in the nickel substrate, desorption from the higher energy binding α-state was reduced, indicating a decrease in the attractive interactions among hydrogen atoms. The hydrogen coverage at saturation was not affected by the addition of copper to the nickel substrate until the copper concentration was greater than 25% at which a sharp reduction in saturation coverage occurred. This phenomenon was apparently due to the adsorption of hydrogen on Ni atoms followed by occupation of NiNi and CuNi bridged adsorption sites, while occupation of CuCu sites was restricted due to an energy barrier to migration.  相似文献   
68.
A fast-frequency modulated (FM) diode laser has been optically narrowed using the technique of resonant optical feedback, to provide linewidths in each FM mode of ≈ 200 kHz peak-to-peak. With a drive frequency of 50 MHz and modulation index of 0.2, the FM laser has been used for the first time to obtain Doppler-free FM spectra of the Rb D1 line at 795 nm. The potential use of this system for laser frequency stabilisation is discussed.  相似文献   
69.
Diffraction by a semitransparent screen is considered in the framework of the nonlinear Schrödinger equation. The case of a defocusing medium is investigated. The method used represents a synthesis of the method of Riemann's matrix problem and the technique of Whitham's deformations of spectral curves.Translated from Zapiski Nauchnykh Seminarov Leningradskogo Otdeleniya Matematicheskogo Instituta im. V. A. Steklova, Vol. 179, pp. 23–31, 1989.  相似文献   
70.
Cognitive style refers to differences that can be perceived in individuals due to differing cognitive structures. There has been a large amount of research on how cognitive style affects managerial decision-making, particularly in the context of management information systems, but little or no attempt to relate these findings to operational research. This paper reviews the findings of cognitive-style research from the perspective of operational research, and draws a number of useful inferences concerning the matching of OR aids to managers, the presentation of information and recommendations, the use and acceptance of OR, and the structure of OR groups. Further, it is argued that cognitive-style findings help to give a justification to the move towards ‘soft’ approaches to analysis.  相似文献   
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