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811.
Geometrical nonlinear waves in finite deformation elastic rods 总被引:1,自引:1,他引:0
IntroductionSomenewphenomenaofnonlinearwavesinthesolidmediumsuchasshockwave ,solitarywaveetc.arepaidmoreattentiontoincreasinglybyresearchersbecausetheytakeonalotofimportantproperties.ItistheoreticallyanalyzedinRefs.[1 -6]thattheformationmechanismsofshockwaveandsolitarywaveintheelasticthinrodsaswellastheirpropagationproperties.TheexistenceofsolitarywaveintheelasticmediumsuchasarodandaplatehasbeenverifiedinRef.[7]byexperiments.Shockwaveandsolitarywavearesteadilypropagatingtraveling_wavesgenerat… 相似文献
812.
Rajneesh Kumar Rupender 《应用数学和力学(英文版)》2009,30(11):1445-1454
The problem of reflection and transmission of plane waves incident on the contact surface of an elastic solid and an electro-microstretch generalized thermoelastic solid is discussed. It is found that there exist five reflected waves, i.e., longitudinal displacement (LD) wave, thermal (T) wave, longitudinal microstretch (LM) wave and two coupled transverse displacement and microrotational (CD(I) and CD(II)) waves in the electro-microstretch generalized thermoelastic solid, and two transmitted waves, i.e., longitudinal (P) and transverse (SV) waves in the elastic solid. The amplitude ratios of different reflected and transmitted waves are obtained for an imperfect boundary and deduced for normal force stiffness, transverse force stiffness, and perfect bonding. The variations of amplitude ratios with incidence angles have been depicted graphically for the LD wave and the CD(I) wave. It is noticed that the amplitude ratios of reflected and transmitted waves are affected by the stiffness, electric field, stretch, and thermal properties of the media. Some particular interest cases have been deduced from the present investigations. 相似文献
813.
HE Han-Xin 《理论物理通讯》2009,52(2):292-294
The transverse symmetry transformations associated with the normal symmetry transformations are proposed to build the transverse constraints on the basic vertices in gauge theories. I show that, while the BRST symmetry in non-Abelian gauge theory QCD (Quantum Chromodynamics) leads to the Slavnov-Taylor identity for the quark-gluon vertex which constrains the longitudinal part of thevertex, the transverse symmetry transformation associated with the BRST symmetry enables to derive the transverse Slavnov-Taylor identity for the quark-gluon vertex, which constrains the transverse part of the quark-gluon vertex from the gauge symmetry of QCD. 相似文献
814.
A nonclassical model for the stress-strain state of a piecewise homogeneous composite bar is proposed. The model is based on an iterative process and takes into account the deplanation of cross sections of the bar caused by transverse shears. Based on the shear strains of some particular approximation, higher approximation models are constructed. The model accounts for both the normal and tangential loads.Presented at the 11th International Conference on Mechanics of Composite Materials (Riga, June 11–15, 2000).Translated from Mekhanika Kompozitnykh Materialov, Vol. 36, No. 4, pp. 487–500, July–August, 2000. 相似文献
815.
讨论一对集中力作用下横观各向同性体三维裂纹的瞬态扩展问题,其解答构成三维裂纹瞬态扩展问题的基本解。求解方法是基于积分变换技术,将混合边值问题化为Wiener-Hopf型积分方程,求得了裂纹所在平面应力和位移的封闭形式解。进一步利用Abel定理和Cagniard-de Hoop方法,求得了动态应力强度因子的精确解。最后通过数值结果揭示了横观各向同性材料三维扩展裂纹尖端场的动态特性。 相似文献
816.
Bending of functionally graded piezoelectric rectangular plates 总被引:25,自引:0,他引:25
By introducing two displacement functions as well as two stress functions, two independent state equations with variable coefficients
are derived from the three-dimensional theory equations of piezoelasticity for transverse isotropy. A laminated approximation
is used to transform the state equations to those with constant coefficients in each sub-layer. The bending problem of a functionally
graded rectangular plate is then analyzed based on the state equations. Numerical results are presented and the effect of
material gradient index is discussed.
Supported by the National Natural Sciences Foundation of China (No. 10002016). 相似文献
817.
基于关联度概念,建立了可以分别检测高阶集合流的方位角关联、横向动量模关联和横向关联的新方法.采用新方法分别分析了1.2A GeV Ar+BaI2碰撞的Bevalac流光室4π实验事件中末态粒子分布的方位角关联与粒子横向动量模的关联对高阶集合流关联的贡献.研究表明:对于这组碰撞实验,末态粒子分布的方位角关联相对横向动量模的关联在高阶集合流关联中起主要作用;末态粒子横向动量模的关联不但可以使粒子群高阶关联的强度有所增加,而且还为在更为狭窄的区间上确定集合流集体性的范围提供了重要信息. 相似文献
818.
819.
S. P. Popov F. G. Tcheremissine 《Journal of Applied Mechanics and Technical Physics》2008,49(1):46-52
Parameters of a rarefied gas flow through a rack of flat plates aligned across the flow are studied by means of the joint
numerical solution of the Boltzmann and Navier-Stokes equations. A subsonic flow regime is considered. The changes in flow
characteristics are calculated as functions of the free-stream velocity and plate temperature.
__________
Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 49, No. 1, pp. 59–67, January–February, 2008. 相似文献
820.
通过对系统施加不同的非线性作用,利用量子关联的几何度量,研究了三个qubit体系中的两体量子关联.不同的非线性相互作用模型都能使系统产生最大值为0.1752的量子关联.z方向的横场对量子关联的优化有控制作用,对于三个模型,通过调节z方向的横场,系统能产生最大值为0.09645的平均量子关联.最佳组合的三个横场,不仅能够大幅度提高量子关联的振荡周期,使得两qubit长时间处于量子关联态,而且还能够提高两qubit的平均量子关联. 相似文献