Particle dispersion in synthetic turbulent flows

We study particle dispersion advected by a synthetic turbulent flow from a Lagrangian perspective and focus on the two-particle and cluster dispersion by the flow. It has been recently reported that Richardson¿s law for the two-particle dispersion can stem from different dispersion mechanisms, and can be dominated by either diffusive or ballistic events. The nature of the Richardson dispersion depends on the parameters of our flow and is discussed in terms of the values of a persistence parameter expressing the relative importance of the two above-mentioned mechanisms. We support this analysis by studying the distribution of interparticle distances, the relative velocity correlation functions, as well as the relative trajectories

A unified framework for shared protection schemes in optical mesh network

While the advantages of p-cycles and FIPP p-cycles are well established, there has been no systematic analysis of how much bandwidth they consume in comparison with the classical shared link and path protection schemes. It was recently observed that, even enumerating a huge number of cycles, is not necessarily a guarantee for obtaining good quality solutions with the ILP models if tools for large scale programming are not used. We propose to investigate the bandwidth protection costs of p-cycles and FIPP p-cycles in comparison with those of shared link and path protection by applying the column generation technique to solve relaxed LP models for the four protection schemes, and then solving the resulting ILP models. Provably near-optimal solutions allow us to perform accurate quantitative comparisons on real-world networks.<br>Embora as vantagens dos p-ciclos e FIPP p-ciclos estejam bem estabelecidas, não existe uma análise sistemática de quanta largura de banda eles consomem em comparação aos mecanismos clássicos de proteção compartilhada por caminhos e por links. Foi observado recentemente que a enumeração de um enorme número de ciclos não é necessariamente uma garantia de se obter soluções de boa qualidade se ferramentas para programação de larga escala não forem usadas. Nós propomos investigar os custos de proteção de largura de banda dos p-ciclos e FIPP p-ciclos em comparação com aqueles de proteção compartilhada por links e por caminhos, através da aplicação da técnica de geração de colunas para resolver modelos relaxados para os quatro esquemas de proteção. Em seguida, resolvemos os modelos de programação inteira resultantes. Soluções próximas da otimalidade nos permitem desempenhar comparações quantitativas exatas em redes reais