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161.
Electric and spatial characteristics of a pulse-periodic microsecond barrier discharge are investigated in different geometries—triangular prism, plate, and corrugated electrode—that are in contact with a dielectric plate and form a dihedral angle with it. It is established that, in the space of the dihedral angle, the regions of discharge represent alternating cylindrical layers with the axes lying on the contact line. The first conducting layer is formed at some distance from the contact edge of the electrode. The number of layers and their localization are determined by the angle formed between an electrode and the dielectric plate. A physical model explaining the main features of the structure formation is proposed.  相似文献   
162.
Two qualitatively different types of resonant destabilization of phonon stimulated emission (SE) are discovered in experiments where a 9-GHz multimode ruby laser is periodically modulated (the electromagnetic pump frequency is 23 GHz). In the case of deep pump modulation at low modulation frequencies (ω=70–200 Hz, where ωm is the modulation frequency), a fast random alternation of microwave phonon SE modes is observed. This destabilization range corresponds to relaxation resonance in optical lasers. Outside the relaxation resonance range (at ωm≈10 Hz), the other type of resonant destabilization of stationary phonon SE is observed. This destabilization shows up as very slow regular self-detunings of the microwave SE spectra. The period of such self-organized motions depends significantly on ωm and changes by several orders of magnitude when ωm varies within several percent. The second type of SE resonant destabilization is explained in terms of antiphase energy exchange between modes in a modulated phaser.  相似文献   
163.
A new formula that relates the acoustic Grüneisen parameter to the Poisson ratio is suggested on the basis of the previously derived expression for this parameter.  相似文献   
164.
165.
Spatial deterministic chaos in optical systems and methods of its modeling   总被引:1,自引:0,他引:1  
The phenomenon of spatial deterministic chaos is described. A transition from an ordinary differential equation to a discrete map is justified for modeling of the chaos. Methods of studying the chaos dynamics in this model are suggested. It is established how the physical properties of a nonlinear ring interferometer influence the structure of charts of the Lyapunov exponents. The approaches developed in the present study allow an optical cryptosystem to be optimized.__________Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 12, pp. 65–71, December, 2004.  相似文献   
166.
Computer models belonging to the class of models of growth controlled by a gradient are investigated. A theoretical approach to the construction of model algorithms of this class allows us to obtain a wide variety of clusters with different structures, including fractal ones. A consideration of gradient increments to the potential leads to the formation of vertical, nonbranching, and insulated clusters corresponding to a long-range potential with large gradient.  相似文献   
167.
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   
168.
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   
169.
N. Elgun  E. A. Davis 《Journal of Non》2003,330(1-3):226-233
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   
170.
Based on an analysis of experimental results and published data, the main elementary steps of the anionic coordination polymerization of butadiene rubber on a cobalt-containing catalyst in the presence of ethylene were found, and a mathematical model of the periodic process at an optimum water content was developed. The molecular-weight characteristics of the process depending on ethylene concentration were studied with the use of this model.  相似文献   
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