Last year, computer output was presented for synthetic pulse-echo data which was processed according to a mathematical imaging technique. This technique was based on the physical optics farfield inverse scattering (acronym, POFFIS) formalism for scattering by volume defects. This year, a number of theoretical advances have been made in the POFFIS formalism, with attendant revisions in the compu...

Realistic and comprehensive mathematical models of the renal concentrating mechanism lead to large Systems of nonlinear differential equations. Their complexity can be considerably reduced by combining like tubules into common structures. Then the different lengths of the combined tubules have to be modeled by the shunt flow technique. The present paper investigates the validity of this methodo...

In many researches and applications in applied mathematics and engineering, we need to generalize the existing results, algorithms or methods in order to apply them to different situations or considerations. Generalization will allow certain particular problems to be solved more efficiently. Here we use some examples in scientific computing to demonstrate the importance of generalization techni...

a multi-objective optimization procedure has been developed to determine some kinetic parameters of free radical polymerization of vinyl acetate based on genetic algorithm. for this purpose, mathematical modeling of free radical polymerization of vinyl acetate is carried out first and then selected kinetic parameters are optimized by minimizing objective functions defined from comparing experim...

In the present work, the mathematical model of a homogeneous, isotropic thermoelastic double porous micro-beam, based on the Euler-Bernoulli theory is developed in the context of Lord-Shulman [1] theory of thermoelasticity. Laplace transform technique has been used to obtain the expressions for lateral deflection, axial stress, axial displacement, volume fraction field and temperature distribut...

This paper studies a new approach to analyze the large deflection behavior of prismatic and non-prismatic beams of non-homogenous material under combined load and multiple boundary conditions. The mathematical formulation has been derived which led to a set of six first-order ordinary differential equations. The geometric nonlinearity was solved numerically using the multiple shooting method co...

In this study, the general partial differential equation of unsteady groundwater flow through non-homogeneous and anisotropic aquifer was solved by the fully implicit finite difference method with control volume approach. The calibration of permeability and storage coefficients as model parameters was performed by a transformation technique and application of Powell's non-linear optimization me...

this paper presents a class of theoretical and iterative method for linear partial differential equations. an algorithm and analytical solution with a initial condition is obtained using the reduced differential transform method. in this technique, the solution is calculated in the form of a series with easily computable components. there test modeling problems from mathematical mechanic, physi...