13 research outputs found
El triple juego de las comunicaciones bidireccionales
Fil: Alvarez-Hamelin, J. Ignacio. Universidad de Buenos Aires. Facultad de Ingeniería; ArgentinaTelefonía, televisión e Internet son actualmente servicios requeridos en la sociedad. Este nuevo paradigma crea intereses entre las empresas que brindan alguno de estos servicios, y el desafío de proveerlos conjuntamente. Sin embargo, la ola de Internet parece cubrirlo todo ya que esta tecnología permite implementar cualquier servicio donde la clave es la propiedad de la bidireccionalidad de las comunicaciones. Internet se inició en los 70 y Argentina comenzó a conectarse a mediados de los 90. En 2000, la red estaba ampliamente difundida y aceptada en el mundo. Este hecho fue observado por las compañías involucradas en el negocio de Internet y en otro tipo de tecnologías de comunicaciones. Surgió entonces el término "triple-play"
Obtaining Communities with a Fitness Growth Process
The study of community structure has been a hot topic of research over the
last years. But, while successfully applied in several areas, the concept lacks
of a general and precise notion. Facts like the hierarchical structure and
heterogeneity of complex networks make it difficult to unify the idea of
community and its evaluation. The global functional known as modularity is
probably the most used technique in this area. Nevertheless, its limits have
been deeply studied. Local techniques as the ones by Lancichinetti et al. and
Palla et al. arose as an answer to the resolution limit and degeneracies that
modularity has.
Here we start from the algorithm by Lancichinetti et al. and propose a unique
growth process for a fitness function that, while being local, finds a
community partition that covers the whole network, updating the scale parameter
dynamically. We test the quality of our results by using a set of benchmarks of
heterogeneous graphs. We discuss alternative measures for evaluating the
community structure and, in the light of them, infer possible explanations for
the better performance of local methods compared to global ones in these cases
Subframework-Based Rigidity Control in Multirobot Networks
This paper presents an alternative approach to the study of distance rigidity
in networks of mobile agents, based on a subframework scheme. The advantage of
the proposed strategy lies in expressing framework rigidity, which is
inherently global, as a set of local properties. Also, we show that a
framework's normalized rigidity eigenvalue degrades as the graph's diameter
increases. Thus, the rigidity eigenvalue associated to each subframework arise
naturally as a local rigidity metric. A decentralized subframework-based
controller for maintaining rigidity using only range measurements is developed,
which is also aimed to minimize the network's communication load. Finally, we
show that the information exchange required by the controller is completed in a
finite number of iterations, indicating the convenience of the proposed scheme.Comment: Copyright 20XX IEEE. Personal use of this material is permitted.
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