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1.
M. S. Nikol’skii 《Computational Mathematics and Modeling》2007,18(4):420-431
We consider the behavior of bundles of optimal controls when the initial state of the system goes to some given vector. We
investigate three types of optimization problems: problems with fixed process length and a free right endpoint; problems with
fixed process length and a fixed right endpoint; time-optimal problems. The article is a review of recent results obtained
by the author.
__________
Translated from Nelineinaya Dinamika i Upravlenie, No. 4, pp. 301–314, 2004. 相似文献
2.
V. A. Naumov H. Oberhammer M. A. Tafipol’skii 《Russian Journal of General Chemistry》2005,75(6):845-850
Geometric parameters and conformation of the bis(trimethylsilyl)hypophosphite molecule were determined by gas-phase electron diffraction and quantum-chemical calculations. The molecule has an asymmetric structure, including an asymmetric P(OSiMe3)2 group. The principal geometric parameters are as follows: (r
a; in parentheses are standard deviations): bond lengths: P-O 1.616 and 1.633(1), Si-O 1.670(1), Si-C 1.892(1), C-H 1.097(3) Å; bond angles: OPO 100.8(8), POSi 133.3, and 138.4(3)°; torsion angles about P-O bonds 120(2) and 41.(3)°; and torsion angles about Si-O bonds are 145 and −178(4)°.__________Translated from Zhurnal Obshchei Khimii, Vol. 75, No. 6, 2005, pp. 897–902.Original Russian Text Copyright © 2005 by Naumov, Oberhammer, Tafipol’skii. 相似文献
3.
L. A. Frolova L. S. Leonova A. A. Arslanova Yu. A. Dobrovol’skii 《Russian Journal of Electrochemistry》2013,49(8):822-826
Effective catalytic systems based on Pt/CeO2-C were prepared. The use of a cerium oxide addition in the substrate stabilized the platinum catalysts against their poisoning with carbon monoxide at room temperature. 相似文献
4.
K. V. Karel’skii A. S. Petrosyan A. V. Chernyak 《Journal of Experimental and Theoretical Physics》2013,116(4):680-697
A set of equations is derived for the motion of a compressible ideal gas over a nonuniform boundary in the gravitational field in the shallow-water approximation. Classical simple waves are shown not to be the solutions to this set of equations. Generalized simple waves are found to exist only in the case of a linear underlying-surface profile. All continuous and discontinuous solutions are obtained in an explicit form for the case of the boundary in the form of an inclined plane, and an analytical solution is found for the problem of the decay of an arbitrary discontinuity. This solution consists of four wave configurations. Necessary and sufficient conditions are determined for the existence of each configuration. 相似文献
5.
A model is proposed to describe the evolution of 180° domains in a ferroelectric. Closed analytic expressions are obtained for the velocity of sideways motion of a 180° domain wall in an electric field and numerical calculations are performed. The connection between polarization reversal and electron emission is discussed. 相似文献
6.
S. E. Savel’ev L. M. Fisher V. A. Yampol’skii 《Journal of Experimental and Theoretical Physics》1998,87(5):978-984
Penetration by Abrikosov flux lines of an isotropic hard superconductor in the critical state induced by changes in the orientation
of external magnetic field has been theoretically investigated. The analysis has been based on the microscopic nonlocal model
taking into account forces of bulk and surface pinning, alongside magnetic forces of interaction of the row of penetrating
vortices with existing flux lines, Meissner currents, and vortex images. New vortices penetrate a superconductor only when
the angle through which the field is rotated is larger than a certain critical value. It has been determined that the alignment
of entering vortices is essentially different from that of the applied magnetic field. The feasibility of detecting noncollinearity
effects is discussed.
Zh. éksp. Teor. Fiz. 114, 1804–1816 (November 1998) 相似文献
7.
A. É. Bugrov S. Yu. Gus’kov V. B. Rozanov I. N. Burdonskii V. V. Gavrilov A. Yu. Gol’tsov E. V. Zhuzhukalo N. G. Koval’skii V. N. Kondrashov M. I. Pergament V. M. Petryakov S. D. Tsoi 《Journal of Experimental and Theoretical Physics》1999,88(3):441-448
We have experimentally investigated the interaction of high-power neodymium laser pulses in the intensity range 1013–1014 W/cm2 with flat low-density (0.5–10 mg/cm3) agar-agar targets under conditions of interest for problems of inertial nuclear fusion. Optical and x-ray methods with high
temporal and spatial resolution were used to examine the dependence of absorption and scattering of the incident beam on the
initial mean density and thickness of the irradiated samples. We show that when a porous target is irradiated, a bulk absorption
layer of high-temperature plasma is produced inside the target whose dimensions are determined by the initial density of the
material. The time dependence and spectral composition of the harmonics 2ω
0 and 3ω
0/2 observed in the plasma-scattered radiation are measured. A theoretical model is developed that describes the interaction
of high-power laser pulses with a porous medium. Predictions of the model, based on the hypothesis of two stages of homogenization
of the target material—a fast stage (0.1–0.3 ns) and a slow stage (1–3 ns), are in good agreement with the experimental data.
Zh. éksp. Teor. Fiz. 115, 805–818 (March 1999) 相似文献
8.
Correlated signals of thermal acoustic radiation from heated sources extending in the transverse direction (a pair of narrow plasticine plates and a wide plasticine strip) are measured. The measurements are performed by multiplying together the signals that are shifted in time with respect to each other and detected by two piezoelectric transducers. The values of the correlated signals of thermal acoustic radiation are determined by the spatial variation of temperature in the medium under study. 相似文献
9.
The acoustoelectromagnetic interaction is examined in a regime where three mechanisms must be taken into account simultaneously:
photoelasticity, quadratic photoelasticity, and elastic nonlinearity. It is shown that beyond the critical conditions, acoustic
solitary waves are formed at harmonic and subharmonic frequencies in a crystal. Including damping and nonideal reflection
at the boundaries does not lead to the establishment of any sort of stationary state: a soliton spatial-temporal dynamic develops.
Fiz. Tverd. Tela (St. Petersburg) 39, 1101–1104 (June 1997) 相似文献
10.
A. A. Kovalevskii V. A. Labunov A. S. Strogova V. V. Tsybul’skii 《Technical Physics》2016,61(9):1343-1345
Nanostructured titanium disilicide powders with semiconductor properties are synthesized and studied. The optical and electrophysical properties of TiSi2 are found to be controlled by its crystallite size. 相似文献