Renormalizing Sznajd model on complex networks taking into account the effects of growth mechanisms

We present a renormalization approach to solve the Sznajd opinion formation model on complex networks. For the case of two opinions, we present an expression of the probability of reaching consensus for a given opinion as a function of the initial fraction of agents with that opinion. The calculations reproduce the sharp transition of the model on a fixed network, as well as the recently observed smooth function for the model when simulated on a growing complex networks.Comment: 5 pages, 7 figure

Dielectric mismatch and shallow donor impurities in GaN/HfO2 quantum wells

In this work we investigate electron-impurity binding energy in GaN/HfO$_2$ quantum wells. The calculation considers simultaneously all energy contributions caused by the dielectric mismatch: (i) image self-energy (i.e., interaction between electron and its image charge), (ii) the direct Coulomb interaction between the electron-impurity and (iii) the interactions among electron and impurity image charges. The theoretical model account for the solution of the time-dependent Schr\"odinger equation and the results shows how the magnitude of the electron-impurity binding energy depends on the position of impurity in the well-barrier system. The role of the large dielectric constant in the barrier region is exposed with the comparison of the results for GaN/HfO$_2$ with those of a more typical GaN/AlN system, for two different confinement regimes: narrow and wide quantum wells.Comment: 6 Pages, 7 figure

Is the Industrial Product-Service System Really Sustainable

As the product-service system has shifted from its original concept to the Industrial PSS, its scope has expanded to include industrial products. Furthermore, the overall goal of reducing environmental impacts has been left behind. Despite the PSS's potential as a business model for a more sustainable production and consumption system, the mere addition of services to conventional products does not necessarily lead to a reduction of environmental impacts. This paper aims to discuss the concepts related to PSS, the need for considering environmental impact reduction as a critical issue for sustainability, and the role of ecodesign practices in the development of PSS

Experimental characterization of the structural response of adobe arches

Earth was one of the first construction materials used by mankind and has been used as a building material since ancient times until the present days. Its qualities related to thermal comfort, low cost or simple construction techniques have contributed to such a long tradition throughout the world with several different architectural expressions, integrating the culture and history of each region. With the wide propagation of steel and concrete structures, there has been a general loss of the traditional knowledge in earth construction. This type of construction presents important structural fragilities and requires a special maintenance to preserve its qualities. In order to understand the structural behaviour of this type of structures, the associated construction methods and processes have to be considered. Aveiro University has been developing studies on adobe constructions, with research on the material mechanical characterization, experimental study of the structural behaviour of adobe masonry walls and, more recently, in the development of a detailed survey methodology for the characterization of buildings in Aveiro district. Integrated in these studies, arches with different geometries were built using adobe blocks and traditional construction methods. These arches were tested under different types of vertical loading (distributed symmetrical, distributed non-symmetrical and point load) until collapse. The experimental tests performed reproduce the typical loading conditions of these structures during construction and use. The tests conducted, the results obtained and the main conclusions attained are described in this paper

The QCD Critical End Point in the Context of the Polyakov--Nambu--Jona-Lasinio Model

We investigate the phase diagram of the so-called Polyakov--Nambu--Jona-Lasinio model at finite temperature and nonzero chemical potential with three quark flavors. Chiral and deconfinement phase transitions are discussed, and the relevant order-like parameters are analyzed. A special attention is payed to the critical end point (CEP): the influence of the strangeness on the location of the CEP is studied; also the strength of the flavor-mixing interaction alters the CEP location, once when it becomes weaker the CEP moves to low temperatures and can even disappear.Comment: Prepared for Strangeness in Quark Matter 2011, Sept. 18--24, Cracow, Polan

Exploring the role of model parameters and regularization procedures in the thermodynamics of the PNJL model

The equation of state and the critical behavior around the critical end point are studied in the context of the Polyakov--Nambu--Jona--Lasinio model. We prove that a convenient choice of the model parameters is crucial to get the correct description of isentropic trajectories. The physical relevance of the effects of the regularization procedure is insured by the agreement with general thermodynamic requirements. The results are compared with simple thermodynamic expectations and lattice data.Comment: Talk given at XIII International Conference on Hadron Spectroscopy (Hadron 2009), Tallahassee, Florida, USA, 29 Nov - 4 Dec, 200

How parameters and regularization affect the PNJL model phase diagram and thermodynamic quantities

We explore the phase diagram and the critical behavior of QCD thermodynamic quantities in the context of the so-called Polyakov--Nambu--Jona-Lasinio model. We show that this improved field theoretical model is a successful candidate for studying the equation of state and the critical behavior around the critical end point. We argue that a convenient choice of the model parameters is crucial to get the correct description of isentropic trajectories. The effects of the regularization procedure in several thermodynamic quantities is also analyzed. The results are compared with simple thermodynamic expectations and lattice data.Comment: 27 pages, 7 figures, 4 tables; PRD versio