transfer matrix method (tmm) has been applied to analyze characteristics of semiconductor laser optical amplifiers. the input signal is sinusoidal modulating wave and we do not assume the modulating bias signal as well. we have shown that the distoration arises from gain modulation at low modulation frequencies, but in microwave modulation frequencies, the gain takes an average value and the re...

This paper proposes two significant developments of the Wittrick–Williams (W–W) algorithm for an exact wave propagation analysis lattice structures based on analytical dynamic stiffness (DS) model each unit cell structures. Based Bloch’s theorem, combination both DS and W–W makes efficient in contrast to existing methods such as finite element method (FEM). Any number or order natural frequenci...

We present Defmod, an open source (linear) finite element code that enables us to efficiently model the crustal deformation due to (quasi-)static and dynamic loadings, poroelastic flow, viscoelastic flow and frictional fault slip. Ali (2015) provides the original code introducing an implicit solver for (quasi-)static problem, and an explicit solver for dynamic problem. The fault constraint is i...

Abstract An accurate frequency domain model is proposed to analyze the seismic response of uniform vertical cylinders with arbitrary cross section surrounded by water. According boundary conditions and using variables separation method, modes hydrodynamic pressure are firstly obtained. Secondly, three-dimensional wave equation can be simplified a two-dimensional Helmholtz equation. Introducing ...

In this paper, the region in which the structural system is situated is divided into four subregions, namely upper, lower, left and right subregions. The stiffness matrix of the entire system is then formed and using the existing direct symmetry and reverse symmetry, the relationships between the entries of the matrix are established. Examples are included to illustrate the steps of the method.

A new method is presented for identifying the local stiffness of a structure from vibration test data. The method is based on a projection of the experimentally measured flexibility matrix onto the strain energy distribution in local elements or regional superelements. Using both a presumed connectivity and a presumed strain energy distribution pattern, the method forms a well-determined linear...

[A] matrix with constants describing the anisotropy of the material [B] strain matrix [BL] linear strain matrix [BNL] nonlinear strain matrix c speed of sound d rate of deformation tensor dp plastic rate of deformation D elastic constitutive tensor [D] matrix of the elastic constitutive tensor [DT] matrix form of the constitutive tensor ds lengths of the vector dx dS lengths of the vector dX dv...

A method for homogenization of an elastic composite with periodic microstructure is presented, focusing on the Floquet-type elastic waves. The resulting homogenized frequency-dependent elasticity and mass density then automatically satisfy the overall conservation laws and by necessity produce the exact dispersion relations. It is also shown that the dispersion relations and the associated fiel...