Design and Implementation Aspects of a novel Java P2P Simulator with GUI

Peer-to-peer networks consist of thousands or millions of nodes that might join and leave arbitrarily. The evaluation of new protocols in real environments is many times practically impossible, especially at design and testing stages. The purpose of this paper is to describe the implementation aspects of a new Java based P2P simulator that has been developed to support scalability in the evaluation of such P2P dynamic environments. Evolving the functionality presented by previous solutions, we provide a friendly graphical user interface through which the high-level theoretic researcher/designer of a P2P system can easily construct an overlay with the desirable number of nodes and evaluate its operations using a number of key distributions. Furthermore, the simulator has built-in ability to produce statistics about the distributed structure. Emphasis was given to the parametrical configuration of the simulator. As a result the developed tool can be utilized in the simulation and evaluation procedures of a variety of different protocols, with only few changes in the Java code.Comment: 8 Pages, 7 figures, This article was accepted for presentation in the IEEE Panhellenic Conference in Informatics (PCI 2008), http://www.aegean.gr/PCI200

Exploring electrical conductivity within mesoscopic phases of semi-conducting PEDOT:PSS films by Broadband Dielectric Spectroscopy

Poly(3,4-ethylenedioxythiophene) : poly(styrene sulfonic acid (PEDOT:PSS), an optically transparent organic semi-conductor, constitutes a suspension of conducting PEDOT:PSS grains, shelled by an insulating layer of PSS. While a percolation network enhances dc conductivity, structural and electrical inhomogenity hinters electric charge flow giving rise to capacitance effects. In the present work, two distinct relaxation mechanisms are detected by Broadband Dielectric Spectroscopy (BDS). Double polarization mechamisms are predicted by bi-phase suspension dielectric theory. Within the frame of interfacial polarization, we propose a methodology to have an insight into the local conductivity of the interior of mesoscopic conducting phase.Comment: 6 figure

MAGNETORESISTANCE OF FeS1.14 SINGLE CRYSTALS FOR B // c

Measurements of the transverse magnetoresistance on natural single crystals of pyrrhotite FeS1.14 revealed a phenomenon of the order 10-3. The shape of the curves Δρ/ρ(0) vs. B for different temperatures is explained and the magnitude of the magnetoresistance can be adequately forseen by the s-d model