in this work the mathematical model of a spatial pattern inchemical and biological systems is investigated numerically. theproposed model considered as a nonlinear reaction-diffusionequation. a computational approach based on finite difference andrbf-collocation methods is conducted to solve the equation withrespect to the appropriate initial and boundary conditions. theability and robustness o...

a multiple-unit oral floating system was prepared using the emulsification-solvent diffusion method to prolong the gastric emptying time of theophylline. for this purpose, theophylline, ethyl cellulose and dibutyl phthalate were dissolved in an ethanol/dichloromethane mixture, added to 0.1 m hcl containing nacl (20%) or saturated theophylline and/or different concentrations of polysorbate 80 an...

fitzhugh-nagumo (fhn) model is a famous reaction-diffusion system which first introduced for the conduction of electrical impulses along a nerve fiber. this model is also considered as an abstract model for pattern formation. here, we have used the cellular automata method to simulate the pattern formation of the fhn model. it is shown that the pattern of this model is very similar to those of ...

the stochastic reaction diffusion systems may suffer sudden shocks‎, ‎in order to explain this phenomena‎, ‎we use markovian jumps to model stochastic reaction diffusion systems‎. ‎in this paper‎, ‎we are interested in almost sure exponential stability of stochastic reaction diffusion systems with markovian jumps‎. ‎under some reasonable conditions‎, ‎we show that the trivial solution of stocha...

The stochastic reaction diffusion systems may suffer sudden shocks‎, ‎in order to explain this phenomena‎, ‎we use Markovian jumps to model stochastic reaction diffusion systems‎. ‎In this paper‎, ‎we are interested in almost sure exponential stability of stochastic reaction diffusion systems with Markovian jumps‎. ‎Under some reasonable conditions‎, ‎we show that the trivial solution of stocha...

In this study, the use of the three-layer feed forward neural network has been investigated for estimating of infinite dilute diffusion coefficient ( D12 ) of supercritical fluid (SCF), liquid and gas binary systems. Infinite dilute diffusion coefficient was spotted as a function of critical temperature, critical pressure, critical volume, normal boiling point, molecular volume in normal boilin...

the cellular automata method has been used to simulate the pattern formation of the schlögl model as a bistable reaction-diffusion system. both microscopic and macroscopic cellular automata approaches have been considered and two different methods for obtaining the probabilities in the microscopic approach have been mentioned. the results show the tendency of the system towards the more stable ...

In this paper we study the topology effects on diffusion process in signed networks. Considering a simple threshold model for diffusion process, it is extended to signed networks and some appropriate definitions are proposed. This model is a basic model that could be extended and applied in analyzing dynamics of many real phenomena such as opinion forming or innovation diffusion in social netwo...