In this paper, a generalized Camassa–Holm equation is studied by using the integral bifurcation method. Many travelling waves such as peaked compacton, compacton, peaked solitary wave, solitary wave and kink-like wave are found. In some parameter conditions, exact parametric representations of these travelling waves in explicit form and implicit form are obtained. 2008 Elsevier Inc. All rights ...

We show how an evolutionary algorithm can successfully be used to evolve a set of difficult to solve symmetric travelling salesman problem instances for two variants of the Lin-Kernighan algorithm. Then we analyse the instances in those sets to guide us towards deferring general knowledge about the efficiency of the two variants in relation to structural properties of the symmetric travelling s...

An auxiliary elliptic equation method is presented for constructing exact solitary and periodic travelling-wave solutions of the K(2, 2) equation (defocusing branch). Some known results in the literature are recovered more efficiently, and some new exact travelling-wave solutions are obtained. Also, new stationary-wave solutions are obtained.

BACKGROUND The accessibility to health centers is a limitation to the use of preventive and curative health centers. AIM To assess geographic accessibility using a parameter that integrates information about the use of preventive services and travelling time from home to the health center. MATERIAL AND METHODS We analyzed target geographical areas of 10 community centers located at the Nort...

This paper considers a sequencing problem which arises naturally in the scheduling of software agents. We are given n sites at which a certain task might be successfully performed. The probability of success is pi at the ith site and these probabilities are independent. Visiting site i and trying the task there requires time (or some other cost metric) ti whether successful or not. Latencies be...

Many oscillatory biological systems show periodic travelling waves. These are often modelled using coupled reaction–diffusion equations. However, the effects of different movement rates (diffusion coefficients) of the interacting components on the predictions of these equations are largely unknown. Here we investigate the ways in which varying the diffusion coefficients in such equations alters...

A non-monotone time-delayed lattice system with global interaction is considered. The spreading speed, including the upward convergence, is established by comparison arguments and a fluctuation method. The existence of travelling waves is obtained by Schauder’s fixed-point theorem and a limiting process. It turns out that the minimal wave speed of travelling waves coincides with the spreading s...

Geometry approach to the theoretical and experimental investigations of peristaltic waves based on the travelling deformation waves and wave mass transfer theory (Dobrolyubov, 1991) is presented. The theory of travelling deformation waves is employed to determine uniformed expressions for mass transfer capability parameters of peristalsis. Slow (quasi-static) wave motion is considered which per...

A parallel ant colony algorithm for the Travelling Salesman Problem (TSP) is presented. Some experiments using a MPI based framework are made and analyzed. The achieved results prove that the TSP parallel implementation is efficient. Key-Words: Travelling Salesman Problem, Ant Colony Optimization, Parallel Algorithms, Framework, Message Passing Interface.

We present a method for the classification of all weak travelling-wave solutions for some dispersive nonlinear wave equations. When applied to the Camassa-Holm or the Degasperis-Procesi equation, the approach shows the existence of not only smooth, peaked and cusped travelling-wave solutions, but also more exotic solutions with fractal-like wave profiles.