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991.
Features of nonlinear deformation and critical states of shell systems with geometrical imperfections 总被引:1,自引:0,他引:1
V. S. Hudramovych 《International Applied Mechanics》2006,42(12):1323-1355
Results from theoretical and experimental investigations into the nonlinear deformation (geometrical nonlinearity, plastic
deformation, creep) and critical states (limit loads, buckling) of shell-frame systems with geometric imperfections are analyzed.
The presence of prestresses is allowed. Diverse effects of various geometrical imperfections and plastic deformation for different
load histories are studied. New qualitative effects of the mutual influence of these factors are established. Relevant experimental
results are outlined
__________
Translated from Prikladnaya Mekhanika, Vol. 42, No. 12, pp. 3–47, December 2006. 相似文献
992.
993.
B. B. Sevruk 《Journal of Applied Spectroscopy》2006,73(5):701-706
A semi-discrete dynamic model has been developed for the formation of the spatial structure of wave fields in a medium with
cubic nonlinearity. The characteristic features of self-focusing and conical modulation of intense Bessel-Gaussian light beams
of different orders have been studied in different stages of their evolution during propagation. It has been shown that as
a result of nonlinear refraction, in the far zone wave structures are formed consisting of three spatially separated conical
beams. Increasing the cone angle of the wave vectors leads to a decrease in the effect of conical modulation of the radiation,
and improves the structural stability of the beam. The considered self-modulation effects can be used for passive limiting
of the laser radiation power.
__________
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 73, No. 5, pp. 626–630, September–October, 2006. 相似文献
994.
995.
The propagation of arbitrary laser beams in strongly nonlocal nonlinear media is investigated based on the ABCD matrix. The second-order moment beam width and the mean curvature radius are derived under the off-waist incident condition. 相似文献
996.
Muhammad Taher Abuelma’atti 《Applied Acoustics》2006,67(9):882-891
Using a model based on subcritical Hopf amplifiers, closed form expressions are obtained for two-tone suppression and the third-order intermodulation performance of the human auditory system. The proposed model approximates the Hopf amplifier characteristic using Fourier-series expansion. The parameters of the Fourier-series approximation can be easily obtained without recourse to sophisticated curve-fitting techniques. The results are compared with previously reported observations. 相似文献
997.
G. V. Petrov 《Thermophysics and Aeromechanics》2008,15(4):563-566
The harmonics of Tollmien—Schlichting waves in a compressible boundary layer of a plate are computed with the aid of nonlinear
parabolized stability equations. At the (downstream) growth of the second harmonic amplitude up to the values of the order
of the basic harmonic amplitude, the amplification rate of the latter is shown to increase abruptly. A similar rapid deviation
from the results of the linear theory characterizes the onset of the boundary-layer transition to turbulent state. Computations
are carried out for the Mach numbers M = 0.01 and 2.
The work was financially supported by the Russian Foundation for Basic Research (Grant No. 05-01-00079a). 相似文献
998.
999.
The finite element equations considering the geometrical nonlinearity of piezoelectric smart structures are derived based
on the total Lagrange method under the assumption of weak coupling between electricity and mechanics. Buckling and post-buckling
of piezoelectric-plate with various boundary conditions are investigated. The calculated results show that piezoelectric effects
and external voltage can hardly affect the buckling and post-buckling characteristics of piezoelectric-plate under uniaxial
pressure while the buckling caused by displacement in-plane has much to do with the electric field.
The present work is supported by the National Natural Science Foundation of China (No. 59635140). 相似文献
1000.
A. R. McGurn 《Complexity》2007,12(5):18-32
A review is given of some of the properties of photonic crystal waveguides containing or interacting with nonlinear optical media including discussions of potential device applications. An introduction is given to photonic crystals, photonic crystal waveguide technologies, the properties of Kerr nonlinear dielectric media, the properties of new types of excitations in these systems known as intrinsic localized modes, and optical bistability. Device designs for switches, waveguide couplers, interferometers, transistors, photonic crystal receivers and transmitters, and photonic crystal sensors are reviewed. © 2007 Wiley Periodicals, Inc. Complexity 12: 18–32, 2007 相似文献