Critical Cooperation Range to Improve Spatial Network Robustness

A robust worldwide air-transportation network (WAN) is one that minimizes the number of stranded passengers under a sequence of airport closures. Building on top of this realistic example, here we address how spatial network robustness can profit from cooperation between local actors. We swap a series of links within a certain distance, a cooperation range, while following typical constraints of spatially embedded networks. We find that the network robustness is only improved above a critical cooperation range. Such improvement can be described in the framework of a continuum transition, where the critical exponents depend on the spatial correlation of connected nodes. For the WAN we show that, except for Australia, all continental networks fall into the same universality class. Practical implications of this result are also discussed

First-order transitions and triple point on a random p-spin interaction model

The effects of competing quadrupolar- and spin-glass orderings are investigated on a spin-1 Ising model with infinite-range random $p$-spin interactions. The model is studied through the replica approach and a phase diagram is obtained in the limit $p\to\infty$. The phase diagram, obtained within replica-symmetry breaking, exhibits a very unusual feature in magnetic models: three first-order transition lines meeting at a commom triple point, where all phases of the model coexist.Comment: 9 pages, 2 ps figures include

Temperature oscillations of magnetization observed in nanofluid ferromagnetic graphite

We report on unusual magnetic properties observed in the nanofluid room-temperature ferromagnetic graphite (with an average particle size of l=10nm). More precisely, the measured magnetization exhibits a low-temperature anomaly (attributed to manifestation of finite size effects below the quantum temperature) as well as pronounced temperature oscillations above T=50K (attributed to manifestation of the hard-sphere type pair correlations between ferromagnetic particles in the nanofluid)

THERMODYNAMIC ANALYSIS AND ECOLOGICAL EFFICIENCY OF A COMBINED CYCLE POWER PLANT

The purpose of this article is to through the analysis of the first law of thermodynamic for a combined cycle determines the ecological coefficient of the same. This system consists of two gas turbines, two heat recovery boilers and a steam turbine, having a total installed capacity of power generation of 500 MW. This plant will be installed in a small town located 180 km from São Paulo. This place was chosen based on technical aspects by present proximity to the pipeline and transmission line, water availability and other favorable environmental aspects of the project. The natural gas that will serve as the plant's fuel will come from the Field of Mexilhão, from the base of Caraguatatuba, and the water used for cooling will come from the Paraíba do Sul River

Cruzamentos dialélicos entre genótipos da coleção nuclear de arroz da Embrapa.

O objetivo do trabalho foi avaliar acessos de arroz presentes na coleção nuclear e seus cruzamentos quanto a produção, determinando-se a heterose e seus componentes, para aumento dessa característica.Conpeex 2010