The distribution of neutron population in nuclear reactor is described by using transport equations. One of possible approximations of neutron transport equation is given by the neutron diffusion equation. The paper presents numerical solution method of one group neutron diffusion equation with one group of delayed neutrons.

ABSTRACT-Application of models for simulation of solute and pollutants transport in soil can reduce time and costs for remediation process. HYDRUS-1D model was developed to simulate the one–dimensional flow of soil water, heat, solute and viruses in variably saturated–unsaturated porous media. The objective of this investigation is to determine the solute transport parameters in disturbed soil ...

accurate prediction of pollution control and environmental protection need a good understanding of pollutant dynamics. numerical model techniques are important apparatus in this research area. so a 2500 line fortran 95 version code was conducted in which using approximate riemann solver, couples the shallow water and pollution transport agents in two dimensions by the aid of unstructured meshes...

Contaminant transport by liquid ow in a porous medium is modeled by the addition of a stochastic term to Darcy's ow equation. The resulting stochastic diierential equation is studied using results from the theory of diiusions as embodied in the Dynkin formula. The resulting integral equation for the probability distribution of uid elements is solved for the case of a spatially homogeneous mediu...

We present a quantum-kinetic equation which describes the transport phenomena in nanoelectronic devices. The equation can be regarded as a generalization of the Boltzmann equation, which describes the operation of the conventional microelectronic devices. The presented equation treats the coherent part of the transport imposed by the nanostructure potential on a rigorous quantum level, utilizin...

a simple mathematical model of steady state  oxygen distribution subject to diffusive transport and non- linear uptake in a retinal cylinder has been developed. the approximate analytical solution to a reaction- diffusion equation are obtained by using series expansions. the computational results for the scaled variables are presented through graphs. the effect of the important parameters (1) d...