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181.
182.
Yu. M. Pechatnikov 《Technical Physics》2003,48(12):1522-1526
Transition (molecular-viscous) isothermal channel flow of rarefied gases is considered. Present-day engineering physical models of transition gas flow and methods of simulation are analyzed and verified in terms of the kinetic theory on the micro-and macrolevels. 相似文献
183.
The influence of the sample orientation on the effective value of the hydrostatic piezoelectric coefficients d
h
(i)
of Sn2P2S6 crystals has been studied. The hydrostatic piezoelectric coefficients d
h
(1)
and d′
h
(3)
, were measured, d
h
(1)
=(244±3) pC/N and d′
h
(3)
=(92±1) pC/N. The hydrostatic piezoelectric coefficient d
h
(3)
for orthogonal axis system was calculated to be d
h
(3)
=(87±2) pC/N. The, optimal orientation of the sample has been found as (Xy l)−20°-cut. Maximal value of the effective hydrostatic piezoelectric coefficient d
h
(1)
equals 260 pC/N. Double rotated samples were also studied. The orientation of the samples insensitive to the pressure has
been found. The theoretical mean value of hydrostatic piezoelectric coefficient (d
h
)
mean
corresponding to randomly oriented Sn2P2S6 grains in a poled composite has been calculated to be (d
h
)
mean
=136 pC/N. 相似文献
184.
Lev Buhovsky 《Israel Journal of Mathematics》2004,143(1):181-187
In this paper we find homological restrictions on Lagrangians in cotangent bundles of spheres and Lens spaces.
This research was supported by the Israel Science Foundation (grand No. 205/02). 相似文献
185.
Harish C. Bahl Stanley Zionts 《The Journal of the Operational Research Society》1987,38(12):1141-1148
Scheduling the production of several items requires the determination of production quantities in different periods in the presence of resource constraints. Several approximate and heuristic algorithms have been proposed to solve this problem. However, no method for finding an optimal solution has as yet been developed. It is shown that the problem may be solved advantageously using Benders' decomposition. The subproblem in Benders' decomposition is shown to be a transportation problem, and some strategies for solving the master problem are indicated. The paper concludes with a sample problem demonstrating the application of the method. 相似文献
186.
Rie Natsui 《Acta Mathematica Hungarica》2005,108(4):299-318
Summary Let Fq be a finite field with q elements. We consider formal Laurent series of Fq -coefficients with their continued fraction expansions by Fq -polynomials. We prove some arithmetic properties for almost every formal Laurent series with respect to the Haar measure. We construct a group extension of the non-archimedean continued fraction transformation and show its ergodicity. Then we get some results as an application of the individual ergodic theorem. We also discuss the convergence rate for limit behaviors. 相似文献
187.
The diffuse scattering of x rays in a four-layer waveguide-type heterostructure is investigated. The dynamic enhancement of
diffuse scattering is detected experimentally in regions corresponding to the excitation of waveguide modes for both the incident
and scattered waves.
Pis’ma Zh. éksp. Teor. Fiz. 66, No. 4, 219–223 (25 August 1997) 相似文献
188.
Results of experimental investigations of the volt-brightness characteristics, frequency dependences of brightness, and the
directional radiation pattern of electroluminescent MSDM, MSCM, and MSDCM emitters, where M stands for the first transparent
and second nontransparent electrodes, S is a semiconductor, D is a thin-film dielectric, and C is a silicone-based composite
liquid dielectric with a powdered segnetoelectric filler, developed on conventional “smooth” and rough glass substrates are
presented. It is shown that electroluminescent structures on rough surfaces have a brightness approximately two times higher
than that of similar structures developed on a “smooth” substrate.
Ul’yanovsk State University, 42, L. Tolstoi St., Ul’yanovsk, 432700, Russia. Translated from Zhurnal Prikladnoi Spektroskopii,
Vol. 64, No. 4, pp. 507–512, July–August, 1997. 相似文献
189.
N. P. Venediktov M. Yu. Glyavin V. E. Zapevalov A. N. Kuftin A. S. Postnikova M. V. Yulpatova 《Radiophysics and Quantum Electronics》1997,40(4):336-342
A scheme for automated study of current-voltage characteristics of gyroresonance devices is developed. The effective emission
spread at the cathodes of powerful gyrotrons is studied by analysis of current-voltage characteristics. Experimental data
on the effective emission spread parameter for different modes are given. The permissible emission spread at the cathodes
of powerful gyrotrons is estimated, and the dependence of the electron beam parameters on the cathode emission spread is presented.
A complex measurement technique showing the contribution of different physical mechanisms to the cathode emission spread is
proposed.
Institute of Applied Physics, Russian Academy of Sciences, Nizhny Novgorod, Russia. Translated from Izvestiya Vysshikh Uchebnykh
Zavedenii, Radiofizika, Vol. 40, No. 4, pp. 506–516, April, 1997. 相似文献
190.