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51.
Chanin PotisookMayuree Natenapit 《Physica B: Condensed Matter》2012,407(4):598-605
The higher-order dielectric responses of composites composed of weakly nonlinear elliptic cylindrical inclusions randomly embedded in linear media are investigated. The general formulae for effective DC coefficients are newly derived by the average field method up to the ninth order and then applied to analyze the effects of inclusion shapes on the effective response. The results are directly transformed to the quasi-static AC response of the composites under the sinusoidal external electric field with fundamental and third harmonic frequencies. The more general relationships between the effective DC and AC coefficients are established up to the seventh order and third harmonic, which are applicable to all weakly nonlinear isotropic composites. 相似文献
52.
A newly designed cylindrical optical micro-rotator which has slopes for trapping and rotation on its upper surface is proposed. The cylindrical shape is effective in decreasing viscous drag force (damping factor) in the medium. A ray-tracing method considering the beam waist is employed to analyze the radiation pressure exerted on the upper surface of the rotator. We have demonstrated optical trapping and high speed rotation for various optical beam parameters such as the lens numerical aperture and the Gaussian mode profile as well as rotator shape parameters including oblique angle, height and diameter. 相似文献
53.
Zhong-Min Cai 《Acta Mechanica Solida Sinica》1991,4(1):89-99
In this paper an analytical solution for finite deformation at the simple extension of a hypoelastic cylindrical bar of grade zero under constant velocity is obtained. It is found that the difference between stress-strain curves at different tensile velocities is only due to the inertial terms in the solution. The axial stress due to inertia increases with the square of ratio of tensile velocities. 相似文献
54.
Scattering of obliquely incident plane acoustic wave by an air-filled, transversely isotropic cylindrical shell immersed in water is investigated theoretically and experimentally. The normal mode expansion technique is employed for analyzing the scattering field, and then resonance modes of the shell appearing in modal scattering form functions are identified performing the resonance scattering analysis. Dispersion curves for Sholte-Stoneley, SH and Lamb waves are obtained and their characteristics are interpreted. Calculated backscattering and resonance spectra as well as dispersion curves are compared with those from ultrasonic experiments for two composite samples having the same nominal composition but fabricated under different conditions. Sensitive change of the dispersion curves is observed for both normal and oblique incidences, which demonstrates the feasibility of systematic inverse evaluation of damage or elastic constants of the composite shell using data from the acoustic scattering measurements. 相似文献
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The bifurcation instability problem for cylindrical shells made of particulate composites with nonlinear elastic matrix and
damaged inclusions is formulated and solved
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Translated from Prikladnaya Mekhanika, Vol. 43, No. 8, pp. 80–91, August 2007. 相似文献
60.
A few facts related to the aberrations for toroidal and plane gratings are presented. Some design aspects of the plane grating-based
monochromator devised by Petersen (1982) are discussed. We also point out that for a cylindrical grating astigmatic correction
can be reduced and suggest that following Petersen’s scheme some improvements in the monochromator performance could be achieved
with such a grating. 相似文献