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JF Mendes

Publications and source records attributed to JF Mendes.

4 recordsLinked to original sources
PubMed2000

Evolution of networks with aging of sites

We study the growth of a network with aging of sites. Each new site of the network is connected to some old site with probability proportional (i) to the connectivity of the old site as in the Barabasi-Albert's model and (ii) to tau(-alpha), where tau is the age of the old site. We find both from simulation and analytically that the network shows scaling behavior only in the region alpha<1. When alpha increases from -infinity to 0, the exponent gamma of the distribution of connectivities [P(k) approximately k(-gamma) for large k] grows from 2 to the value for the network without aging. The ensuing increase of alpha to 1 causes gamma to grow to infinity. For alpha>1, the distribution P(k) is exponentional.

Journal Article↗
PubMed2000

Bak-sneppen model near zero dimension

We consider the Bak-Sneppen model near zero dimension, where the avalanche exponent tau is close to 1 and the exponents &mgr; and sigma are close to 0. We demonstrate that tau-1=&mgr;-sigma=exp-&mgr;(-1)-gamma+ small middle dot small middle dot small middle dot in this limit, where gamma is Euler's constant. The avalanche hierarchy equation is rewritten in a form that makes it possible to find the relation between the critical exponents sigma and &mgr; with high accuracy. We obtain precise values of the critical exponents for the one and two-dimensional Bak-Sneppen model and for the one-dimensional anisotropic Bak-Sneppen model.

Journal Article↗