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991.
The chaotic dynamics and global bifurcations of the suspended elastic cable under combined parametric and external excitations are investigated. The non-linear equations of motion of the elastic cable to small vibration of one support are derived. The averaged equations are obtained by using the method of multiple scales. Based on the averaged equations, the theory of normal form and Maple program are used to obtain the explicit expressions of normal form associated with a double zero and a pair of pure imaginary eigenvalues. On the basis of the normal form, global bifurcation analysis of the parametrically and externally excited suspended elastic cable is given by a global perturbation method developed by Kovacic and Wiggins. The chaotic motion of the elastic cable is also found by numerical simulation. 相似文献
992.
A new general constitutive model in terms of the principal stretches is proposed to reflect limiting chain extensibility resulting
in severe strain-stiffening for incompressible, isotropic, homogeneous elastic materials. The strain-energy density involves
the logarithm function and has the general Valanis–Landel form. For specific functions in the Valanis–Landel representation,
we obtain particular strain-energies, some of which have been proposed in the recent literature. The stress–stretch response
in some basic homogeneous deformations is described for these particular strain-energy densities. It is shown that the stress
response in these deformations is similar to that predicted by the Gent model involving the first invariant of the Cauchy–Green
tensor. The models discussed here depend on both the first and second invariants.
相似文献
993.
利用我们提出的求正规形的新方法[1],推导高维非线性动力系统的多重非内共振Hopf分岔正规形(系统的Jacobi矩阵有多对比值为无理数的纯虚特征值出现的情况),给出原系统系数与其正规形系数之间的简单的关系式. 相似文献
994.
《Journal of Electrostatics》2014,72(5):381-386
Combined with the Fast Fourier Transform (FFT), a mathematical hybrid method for accurately computing the lightning response from grounding systems buried in multilayered earth model has been developed in this paper. In the method, electrical circuit consists of “T” typical of basic elements. To accelerate calculations of the method, quasi-static complex image method and closed form of Green's function and analytical formula for mutual induction and impedance coefficients were introduced into this method. With the inverse FFT, the method can be used for studying performances of transient lightning response from the grounding systems. 相似文献
995.
Celal Tuğrul Zeyrek Nefise Dilek Mustafa Yıldız Hüseyin Ünver 《Molecular physics》2014,112(19):2557-2574
Synthesis, crystallographic characterisation, spectroscopic (Fourier transform infrared spectroscopy [FT-IR]) and density functional modelling studies of the Schiff base 1-[(4-ethoxyphenylimino)methyl]napthalene-2-ol (C19H17NO2) have been reported. The molecular structure obtained from X-ray single-crystal analysis of the investigated compound in the ground state has been compared using Hartree–Fock and density functional theory (DFT) with the 6-311++G(d,p) basis set. In addition to the optimised geometrical structures, atomic charges, molecular electrostatic potential, natural bond orbital, non-linear optical (NLO) effects and thermodynamic properties of the compound have been investigated by using DFT. The experimental (FT-IR) and calculated vibrational frequencies (using DFT) of the title compound have been compared. The solvent effect was also investigated for obtained molecular energies and the atomic charge distributions of the compound. There exists a good correlation between experimental and theoretical data for enol-imine form of the compound. The total molecular dipole moment (µ), linear polarisability (α), and the first-order hyperpolarisability (β) were predicted by the B3LYP method with different basis sets 6-31G(d), 6-31+G(d,p), 6-31++G(d,p), 6-311+G(d) 150 and 6-311++G(d,p) for investigating the effects of basis sets on the NLO properties. Our computational results yield that βtot for the title compound is greater than those of urea. 相似文献
996.
997.
将正螺面引入到一般的空间型中,在Beltrami-Klein坐标系下统一加以表示,并一致地详尽考察其度量、法向、第二基本形式及主曲率,推出正螺面是极小曲面. 相似文献
998.
《Communications in Nonlinear Science & Numerical Simulation》2014,19(5):1270-1278
A characterization of the general linear equation in standard form admitting a maximal symmetry algebra is obtained in terms of a simple set of conditions relating the coefficients of the equation. As a consequence, it is shown that in its general form such an equation can be expressed in terms of only two arbitrary functions, and its connection with the Laguerre–Forsyth form is clarified. The characterizing conditions are also used to derive an infinite family of semi-invariants, each corresponding to an arbitrary order of the linear equation. Finally a simplifying ansatz is established, which allows an easier determination of the infinitesimal generators of the induced pseudo group of equivalence transformations, for all the three most common canonical forms of the equation. 相似文献
999.
1000.
We establish the Default Barrier Intensity (DBI) model, based on the conditional survival probability (also called hazard function barrier), which allows the pricing of credit derivatives with stochastic parameters. Moreover, the DBI is an analytic model which combines the structural and the reduced form approaches. It deals with the impact of the default barrier intensity on the processes around the firm. Using this model we prove the Doob–Meyer decomposition of the default process associated with the random barrier. In this framework, we present the default barrier process as the sum of its compensator (which is a predictable process) and a martingale related to the smallest filtration making the random barrier a stopping time. Furthermore, the DBI as well as the Shifted Square Root Diffusion (SSRD) Alfonsi’s model emphasizes on the dependence between the stochastic default intensity and the interest rate. This model can be useful since it can be easily generalized to all the credit derivatives products such as Collateralized Debt Obligations (CDO) and Credit Default Swaps (CDS). 相似文献