Density waves are investigated analytically and numerically in the optimal velocity model with reaction-time delay of drivers. The stability condition of this model is obtained by using the linear stability theory. The results show that the decrease of reaction-time delay of drivers leads to the...

We investigate the effect of obstacles on formation of a traffic jam for a traffic flow in a network of city roads. We consider a square lattice of two bonds between two nearest crossings as a network of city roads; we assume that there are three lattice sites in a crossing. We put five...

Fractals and multifractals and their associated scaling laws provide a quantification of the complexity of a variety of scale invariant complex systems. Here, we focus on lattice multifractals which exhibit complex exponents associated with observable log-periodicity. We perform detailed...

We study the relation between different social behaviors and the onset of epidemics in a model for the dynamics of sexual transmitted diseases. The model considers the society as a system of individual sexuated agents that can be organized in couples and interact with each other. The different...

The efficient simulation of models defined in terms of stochastic differential equations (SDEs) depends critically on an efficient integration scheme. In this article, we investigate under which conditions the integration schemes for general SDEs can be derived using the Trotter expansion. It...

The Susceptible-Infected-Removed or SIR model, as it was formulated by Kermack and McKendrick, is the key model for epidemic dynamics. Most applications of such a basic scheme use a constant rate for the removal term. However, that assumption corresponds to the rather unrealistic exponential...

We have introduced recently a model for the spread of sexually transmitted diseases, in which the social behavior is incorporated as a key factor for the further propagation of the infection. The system may be regarded as a society of agents where in principle anyone can sexually interact with...

A phenomenon of alternate constrictions and dilatations in blood vessels has been studied for over 50 years. Recently, a theory has been presented involving a Rayleigh type instability. We analyze the model in terms of the lengths of the deformations in relation to the wall thickness, blood...

The mA + nB → Ø diffusion limited reaction with homogeneous initial condition is studied analytically and numerically. Through renormalization group arguments, it is shiown that the system exhibits the anomalous kinetic behavior below the critical dimension dc∗ ≡ 4/(m + n − 1)....

The complex and chaotic dynamics of a one-dimensional plasma-filled diode is numerically explored by a particle-in-cell simulation. The system has just one control parameter, namely, the electron transit angle, and presents a complex behavior as a function of such a parameter. We report here the...