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981.
Formulas for calculating the spectral characteristics of waveguide arrays, which are incorporated into waveguide spectrum analyzers based on planar waveguides, channel waveguides, and fiber optical waveguides, are derived taking into account the contribution of both the waveguide dispersion and the material dispersion to the dispersion factor. These formulas are used to study the dependence of the dispersion factor on the waveguide-system parameters for specific models of waveguide arrays. It is shown that consideration of contributions of the waveguide dispersion and material dispersion can affect profoundly the spectral characteristics of waveguide arrays. 相似文献
982.
N. V. Boev 《Acoustical Physics》2004,50(6):651-656
This study is devoted to the development of the ray theory of diffraction in application to arbitrary (nonconvex) smooth obstacles in the scalar case. A three-dimensional problem is considered. An asymptotic method of estimating the diffraction integrals is described. The method is based on the multidimensional stationary phase approach. The diffraction integrals are obtained on the basis of the generalization of the Kirchhoff physical theory of diffraction. Explicit expressions are derived for the pressure in the reflected wave in the cases of its single and double reflections. 相似文献
983.
N. A. Zimbovskaya 《Journal of Experimental and Theoretical Physics》2004,98(6):1231-1236
We present theoretical studies of the temperature and magnetic field dependences of the Coulomb drag transresistivity between two parallel layers of two-dimensional electron gases in the quantum Hall regime near half-filling of the lowest Landau level. It is shown that Fermi-liquid interactions between the relevant quasi-particles can significantly affect the transresistivity, providing its independence of the interlayer spacing for spacings that take values reported in the experiments. The obtained results agree with the experimental evidence. 相似文献
984.
Yu. V. Pyatkov V. V. Pashkevich W. H. Trzaska G. G. Adamian N. V. Antonenko D. V. Kamanin V. A. Maslov V. G. Tishchenko A. V. Unzhakova 《Physics of Atomic Nuclei》2004,67(9):1726-1730
An analysis of the preferable fission path manifesting itself as a fine structure of the total kinetic energy-mass distribution of the fission fragments compelled us to put forward an absolutely new shape of the fissioning system on the descent from the fission barrier. It is a multicomponent nuclear molecule constituted by two magic clusters and a torus-like neck between. 相似文献
985.
Physics of Atomic Nuclei - The results of various experiments that measured a single-spin asymmetry in inclusive pion production are analyzed in the energy range between 13 and 200 GeV. The... 相似文献
986.
A. N. Rutenko 《Acoustical Physics》2003,49(4):449-454
Experimental data obtained by studying the effect of internal waves with known space-time parameters on the propagation of a 240-Hz tone signal and on the space-time interference structure of the sound field generated by a noiselike sound source are presented. 相似文献
987.
The effect of the lattice deformation on the electronic spectra of TlGaS2, TlGaSe2, and TlInS2 layered semiconductor crystals is analyzed. It is shown that changes in the band gap of these semiconductors due to thermal expansion and a change in the composition under hydrostatic or uniaxial pressure can be described within a unified model of the deformation potential. The main feature of this model is the inclusion of deformation potentials with different signs, which is characteristic of other semiconductors with a layered structure. An analysis of the lattice deformation of the studied semiconductors in terms of the proposed model of the deformation potential has revealed that, in the immediate vicinity of the phase transitions, the crystal lattice under pressure undergo an unusual deformation. 相似文献
988.
The existing model for multivariate skew normal data does not cohere with the joint distribution of a random sample from a
univariate skew normal distribution. This incoherence causes awkward interpretation for data analysis in practice, especially
in the development of the sampling distribution theory. In this paper, we propose a refined model that is coherent with the
joint distribution of the univariate skew normal random sample, for multivariate skew normal data. The proposed model extends
and strengthens the multivariate skew model described in Azzalini (1985,Scandinavian Journal of Statistics,12, 171–178). We present a stochastic representation for the newly proposed model, and discuss a bivariate setting, which confirms
that the newly proposed model is more plausible than the one given by Azzalini and Dalla Valle (1996,Biometrika,83, 715–726). 相似文献
989.
990.
Hydrogenated amorphous GaP films have been prepared by reactive rf sputtering. Infrared spectroscopy, optical transmission and reflection, photothermal deflection spectroscopy and dc conductivity have been studied to investigate the local bonding configurations, the optical absorption edges and the temperature dependence of the conductivity as a function of hydrogen content. The results are discussed and compared with the effects of hydrogenation on amorphous Si. 相似文献