Computer Science, № 27, 2008

A Cellular Automaton (CA) is nowadays an object of ever growing interest as a mathematical model for spatial dynamics simulation. Due to the CA ability to simulate nonlinear and discontinuous processes, it is expected to become a complement to partial differential equations. Particularly, the CA may be helpful when there...

We consider a market model, which has arised under conditions of the paid usage of CPU time. A new algorithm for calculating the price of the local (for one processor) equilibrium is offered under the assumption that the users' preferences are described by the Cobb-Douglas utility functions. An example shows...

For implementation of pseudo-random number generators (PRNG), a linear congruential generator (LCG) is the most frequently used algorithm. The techniques to increase the efficiency of the LCG based on 64-bit integers and bit-wise operations are studied. The efficiency of the LCG implementation with the techniques proposed is experimentally tested.

For simulating physical and chemical processes on molecular level, asynchronous cellular automata with probabilistic transition rules are widely used being sometimes referred to as Monte-Carlo methods. The simulation requires a huge cellular space and millions of iterative steps for obtaining the CA evolution representing a real scene of the process...

Two statistical lattice models of a 3D crystal are proposed, which allow us to take into account a change in the shape and in the surface morphology of a nanoparticle under the influence of the temperature. It has been shown that consecutive diffusion of atoms does not give reasonable simulation...

The Lattice Gas Automata (LGA) models are based on a microscopic model of physical process being simulated and can be considered as an adjunct to the traditional numerical methods to the spatial dynamics simulation. Here we consider two simple LGA models: HPP and HPPRP. They are based on a square...

An extension to the Lattice-Gas Boolean models up to integer values of the particle velocity vectors is proposed. A new FHP-MP model is featured. Experiments on simulation of a fluid using the new model were carried out. The comparison with the known results is made.

The problem of smoothness of adaptive meshes produced by the Self-Organizing Maps is considered. It is shown that to improve the mesh smoothness, it is necessary to increase the learning radius. This leads, in turn, to the border effect. The main goal of this paper is to develop a technique...

In this paper, we propose an extended version of the associative graph- machine. Then we offer efficient algorithms for implementing the second group of relational algebra operations that consists of operations Product, Join, and Union. The proposed algorithms are represented as the corresponding procedures for the AG-machine. We prove their...

A new method is proposed to reduce non-physical effects in the PIC method. The method is demonstrated on an example of simulation of recombination of positive and negative ions in the radio frequency (RF) discharge.

In discharges in electro-negative gases, the negative ions are generated by dissociative attachment and lost...

Algorithms for mapping a weight matrix of a neural layer onto distributed computer systems with a torus structure are proposed for parallel image processing. It is shown that the choice of the mapping technique depends upon the ratio between the number of neurons and the number of weight coefficients in...