P2PStudio - Monitoring, Controlling and Visualization Tool for Peer-to-Peer Networks Research

Peer-to-Peer Studio has been developed as a monitoring, controlling and visualization tool for peer-to-peer networks. It uses a centralized architecture to gather events from a peer-to-peer network and can be used to visualize network topology and to send different commands to individual peer-to-peer nodes. The tool has been used with Chedar Peer-to-Peer network to study the behavior of different peer-to-peer resource discovery and topology management algorithms and for visualizing the results of NeuroSearch resource discovery algorithm produced by the Peer-to-Peer Realm network simulator. This paper presents the features, the architecture and the protocols of Peer-to-Peer Studio and the ex…

Advertising Peer-To-Peer Networks over the Internet

Weber, Matthieu Advertising Peer-to-Peer Networks over the Internet Jyvaskyla: University of Jyvaskyla, 2006, 120 p. (Jyvaskyla Licentiate Theses in Computing ISSN 1795-9713; 7) ISBN 951-39-2329-0 Finnish summary Most peer-to-peer networks nowadays are decentralized or even fully distributed, meaning that they do not require a central authority for proper operation. Joining such networks is however often performed by using a central directory of its members, thus breaking their decentralized characteristic. This work proposes an advertisement system for peer-to-peer networks that does not rely on a central service, nor requires any dedicated infrastructure to be setup, using only already ex…

Study on the Effects of Pseudorandom Generation Quality on the Performance of Differential Evolution

Experiences in the field of Monte Carlo methods indicate that the quality of a random number generator is exceedingly significant for obtaining good results. This result has not been demonstrated in the field of evolutionary optimization, and many practitioners of the field assume that the choice of the generator is superfluous and fail to document this aspect of their algorithm. In this paper, we demonstrate empirically that the requirement of high quality generator does not hold in the case of Differential Evolution.

Mobile Encounter Networks and Their Applications

This article presents mobile encounter networks (MENs), which emerge when mobile devices come across each other and form a temporary connection between them using a common short-range radio technology. Local information exchanges between mobile devices results in a broadcast diffusion of information to other users of the network with a delay. Gasoline price comparison system (GPCS), which delivers newest gasoline prices to mobile users using mobile encounter information diffusion, is described as well as other application areas where MENs could be used. The feasibility of building MENs using bluetooth is tested with the BlueCheese mobile encounter network middleware and it is found that the…

Modelling Mobile Encounter Networks

This article presents mobile encounter networks, which emerge when mobile devices come across each other and form a temporary connection between them using a common short-range radio technology. Local information exchanges between mobile devices results in a broadcast diffusion of information to other users of the network with a delay. In addition to presenting the concept of mobile encounter networks, we also provide an abstract method for describing the information diffusion process inside them. peerReviewed

Parallel global optimization : structuring populations in differential evolution

Optical properties of ZnO deposited by atomic layer deposition (ALD) on Si nanowires

International audience; In this work, we report proof-of-concept results on the synthesis of Si core/ ZnO shell nanowires (SiNWs/ZnO) by combining nanosphere lithography (NSL), metal assisted chemical etching (MACE) and atomic layer deposition (ALD). The structural properties of the SiNWs/ZnO nanostructures prepared were investigated by X-ray diffraction, Raman spectroscopy, scanning and transmission electron microscopies. The X-ray diffraction analysis revealed that all samples have a hexagonal wurtzite structure. The grain sizes are found to be in the range of 7-14 nm. The optical properties of the samples were investigated using reflectance and photoluminescence spectroscopy. The study o…

Highly textured boron/nitrogen co-doped TiO2 with honeycomb structure showing enhanced visible-light photoelectrocatalytic activity

International audience; In this work, we report a novel photocatalyst based on boron and nitrogen co-doped TiO2 rutile (1 1 0) honeycomb structures. The photocatalyst has been prepared by simultaneously oxidizing and doping a Ti-foil substrate at 750 degrees C. The unit cell volume and the crystallite size of grown TiO2 films were measured by Rietveld refinement analysis. The co-doping by boron and nitrogen was achieved simultaneously with the oxidation of the titanium, resulting in a rutile (1 1 0) textured TiO2 film. X-ray photoelectron spectroscopy analysis revealed the presence of Ti-O-N and Ti-O-B-N bonds, and the presence of crystal defects in the lattice was detected and displayed by…

Chedar: Peer-to-Peer Middleware

In this paper we present a new peer-to-peer (P2P) middleware called CHEap Distributed ARchitecture (Chedar). Chedar is totally decentralized and can be used as a basis for P2P applications. Chedar tries to continuously optimize its overlay network topology for maximum performance. Currently Chedar combines four different topology management algorithms and provides functionality to monitor how the peer-topeer network is self-organizing. It also contains basic search algorithms for P2P resource discovery. Chedar has been used for building a data fusion prototype and a P2PDisCo distributed computing application, which provides an interface for distributing the computation of Java applications.…

A Study on scale factor in distributed differential evolution.

This paper proposes the employment of multiple scale factor values within distributed differential evolution structures. Four different scale factor schemes are proposed, tested, compared and analyzed. Two schemes simply employ multiple scale factor values and two also include an update logic during the evolution. The four schemes have been integrated for comparison within three recently proposed distributed differential evolution structures and tested on several various test problems. Numerical results show that, on average, the employment of multiple scale factors is beneficial since in most cases it leads to significant improvements in performance with respect to standard distributed alg…