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71.
The diffraction of a plane wave incident on a thick hologram at the first and second Bragg angles in the process of nonlinear recording is analyzed using the coupled-wave equations. It is shown that, in this case, the two-wave approximation with the use of effective modulation amplitudes of the refractive index, n 1ef and n 2ef, can be applied. Analytical dependences of n 1ef and n 2ef on the modulation amplitudes of the refractive index n 1 and n 2 at the fundamental and doubled spatial frequencies are obtained and the criteria of their applicability are determined. The dependences found are used to calculate the parameters of gratings recorded in a photopolymeric material. 相似文献
72.
Gianpiero Cattaneo Alberto Leporati Roberto Leporini 《International Journal of Theoretical Physics》2004,43(7-8):1769-1791
We introduce some conservative gates for finite-valued logics which are able to realize all the main connectives of the many-valued logics of ?ukasiewicz, the MV-algebras of Chang and Brower–Zadeh algebras. After a brief exposition of the motivations for this work, the gates are defined and their properties are explored. Finally, a possible quantum realization of them is proposed, using three techniques: a “brute force” method--an extension of the Conditional Quantum Control argument, and a new technique which we call the Constants Method. For all these techniques, the unitary operator which describes the gate is a sum of local operators. 相似文献
73.
A scheme of nuclear excitation by the ionic X-ray lines in laser plasma using two femtosecond laser pulses is proposed. The first pulse produces plasma with a given degree of ionization, allowing the X-ray line energies of the target ions to be tuned to resonance with the nuclear transition, while the second pulse generates hot electrons that are necessary for X-ray generation. 相似文献
74.
Juan A. Barceló Jonathan Bennett Alberto Ruiz 《Journal of Fourier Analysis and Applications》2003,9(6):541-562
We study the continuity properties of a projection derived from a recent characterization of Herglotz Wave Functions in the plane. Herglotz Wave Functions are the entire solutions of the Helmholtz equation which have L2-Far-Field-Pattern. The behavior of this projection is reminiscent of the Disc Multiplier Operator on both Lp and mixed Lp-normed spaces. In particular a Kakeya type set plays a central role in our analysis. As a consequence we answer a question posed by Alvarez, Folch-Gabayet and Pérez-Esteva. 相似文献
75.
76.
A. Puiu G. Giubileo G. Addolorato L. Revelli G. Gasbarrini R. Bellantone A. D’Amore C. P. Lombardi C. Carrozza 《Laser Physics》2007,17(4):448-452
Nowadays, there is high demand for sensitive gas sensors both for human and environmental monitoring. This paper deals with a high-resolution (0.2 ppb) laser-based photoacoustic spectroscopic system realized at ENEA Frascati, Italy, applied for monitoring stress in scuba divers during sustained immersion by analyzing breath samples. Blood tests and psychometric tests for scuba divers were performed at Catholic University in Rome. Results will be reported and discussed. 相似文献
77.
A. B. Vasil’eva 《Ukrainian Mathematical Journal》2007,59(3):396-408
We present results from the theory of singular perturbations and, in particular, from a new branch of this theory (contrast
alternating-type structures).
__________
Translated from Ukrains’kyi Matematychnyi Zhurnal, Vol. 59, No. 3, pp. 359–369, March, 2007. 相似文献
78.
Yu. K. Dem’yanovich 《Journal of Mathematical Sciences》2007,144(6):4548-4567
On a sequence of embedded nonuniform grids, chains of embedded spaces of minimal splines (not necessarily polynomial) are
constructed. The wavelet decomposition is given. The basis wavelets are compactly supported and admit simple analytic representation.
The corresponding decomposition and reconstruction formulas are derived. The variety of spaces under consideration is identified
with the variety of complete sequences of points of the direct product of an interval and a projective plane. Bibliography:
20 titles.
__________
Translated from Problemy Matematicheskogo Analiza, No. 35, 2007, pp. 15–31 相似文献
79.
80.
N. B. Valetova L. L. Semenycheva I. S. Il’ichev A. N. Artemov D. F. Grishin 《Russian Journal of Applied Chemistry》2007,80(5):818-821
Features of radical polymerization of styrene in the presence of (diphenylbutadiene)tricarbonylchromium were studied. 相似文献