1,135 research outputs found
Self-organizing social hierarchies on scale-free networks
In this work we extend the model of Bonabeau et al. in the case of scale-free
networks. A sharp transition is observed from an egalitarian to an hierarchical
society, with a very low population density threshold. The exact threshold
value also depends on the network size. We find that in an hierarchical society
the number of individuals with strong winning attitude is much lower than the
number of the community members that have a low winning probability
IMDB network revisited: unveiling fractal and modular properties from a typical small-world network
We study a subset of the movie collaboration network, imdb.com, where only
adult movies are included. We show that there are many benefits in using such a
network, which can serve as a prototype for studying social interactions. We
find that the strength of links, i.e., how many times two actors have
collaborated with each other, is an important factor that can significantly
influence the network topology. We see that when we link all actors in the same
movie with each other, the network becomes small-world, lacking a proper
modular structure. On the other hand, by imposing a threshold on the minimum
number of links two actors should have to be in our studied subset, the network
topology becomes naturally fractal. This occurs due to a large number of
meaningless links, namely, links connecting actors that did not actually
interact. We focus our analysis on the fractal and modular properties of this
resulting network, and show that the renormalization group analysis can
characterize the self-similar structure of these networks.Comment: 12 pages, 9 figures, accepted for publication in PLOS ON
A model for the advantage of early electron cyclotron current drive in the suppression of neoclassical tearing modes
Experimental Demonstration of the Stabilizing Effect of a Superthermal Electron Avalanche during ECRH
The conundrum of functional brain networks: small-world efficiency or fractal modularity
The human brain has been studied at multiple scales, from neurons, circuits,
areas with well defined anatomical and functional boundaries, to large-scale
functional networks which mediate coherent cognition. In a recent work, we
addressed the problem of the hierarchical organization in the brain through
network analysis. Our analysis identified functional brain modules of fractal
structure that were inter-connected in a small-world topology. Here, we provide
more details on the use of network science tools to elaborate on this behavior.
We indicate the importance of using percolation theory to highlight the modular
character of the functional brain network. These modules present a fractal,
self-similar topology, identified through fractal network methods. When we
lower the threshold of correlations to include weaker ties, the network as a
whole assumes a small-world character. These weak ties are organized precisely
as predicted by theory maximizing information transfer with minimal wiring
costs.Comment: 14 pages, 8 figure
Closed form solution for the equations of motion for constrained linear mechanical systems and generalizations: An algebraic approach
- …