Analytical study of tunneling times in flat histogram Monte Carlo

We present a model for the dynamics in energy space of multicanonical simulation methods that lends itself to a rather complete analytic characterization. The dynamics is completely determined by the density of states. In the \pm J 2D spin glass the transitions between the ground state level and the first excited one control the long time dynamics. We are able to calculate the distribution of tunneling times and relate it to the equilibration time of a starting probability distribution. In this model, and possibly in any model in which entering and exiting regions with low density of states are the slowest processes in the simulations, tunneling time can be much larger (by a factor of O(N)) than the equilibration time of the probability distribution. We find that these features also hold for the energy projection of single spin flip dynamics.Comment: 7 pages, 4 figures, published in Europhysics Letters (2005

Large time behavior for vortex evolution in the half-plane

In this article we study the long-time behavior of incompressible ideal flow in a half plane from the point of view of vortex scattering. Our main result is that certain asymptotic states for half-plane vortex dynamics decompose naturally into a nonlinear superposition of soliton-like states. Our approach is to combine techniques developed in the study of vortex confinement with weak convergence tools in order to study the asymptotic behavior of a self-similar rescaling of a solution of the incompressible 2D Euler equations on a half plane with compactly supported, nonnegative initial vorticity.Comment: 30 pages, no figure

Context-aware mobile app for the multidimensional assessment of the elderly,

Rural areas in Europe are presenting a decreasing population density and an increasing age index. These elders usually present multiple diseases that require complex tools to identify the exact cares that they need. Currently, different frameworks can evaluate their functional status and identify the required cares to maintain their Quality of Life, together with the associated cost to the health system. Nevertheless, these frameworks are usually questionnaires that have to be performed by already overloaded professionals. In this paper, we make use of mobile technologies to build a system capable of monitoring the activities of the elderly and analysing these data to assess their functional status. The experiments carried out show us that it correctly evaluates these patients and reduces the effort required by health professionals

A fileira das plantas aromáticas e medicinais em Portugal

Esta comunicação insere-se no âmbito do projecto Agro nº800 “ Rede Nacional para a Conservação e Utilização de Plantas Aromáticas e Medicinais “ e pretende analisar a fileira PAM em Portugal com o objectivo de conhecer os agentes intervenientes nesta fileira, as operações técnicas realizadas, o grau de integração entre agentes, a organização interna e articulação com o exterior. Neste sentido foram efectuados inquéritos a produtores, distribuidores e transformadores de PAM e seus derivados. Relativamente aos produtores interessou-nos saber que espécies produziam, qual o peso da produção PAM na produção total, preços praticados e modalidades de escoamento da produção, nomeadamente a existência de vínculos contratuais a juzante. No sector da distribuição tentou-se analisar as quantidades e preços dos produtos transaccionados bem como as operações físicas e tecnológicas desenvolvidas por este sector e, ainda, a organização dos sistemas de comercialização e distribuição. Com o inquérito aos transformadores pretendia-se obter informações sobre a facilidade de abastecimento em matéria prima, as quantidades e preços das matérias primas e dos produtos transformados e circuitos de comercialização de produtos transformados. O tratamento da informação obtida por inquérito veio corroborar algumas das ideias pré-existentes nomeadamente a fraca organização e profissionalização da fileira PAM e fornecer elementos importantes para o conhecimento e melhoria da fileira PAM em Portugal.INIA

Effective transport barriers in nontwist systems

In fluids and plasmas with zonal flow reversed shear, a peculiar kind of transport barrier appears in the shearless region, one that is associated with a proper route of transition to chaos. These barriers have been identified in symplectic nontwist maps that model such zonal flows. We use the so-called standard nontwist map, a paradigmatic example of nontwist systems, to analyze the parameter dependence of the transport through a broken shearless barrier. On varying a proper control parameter, we identify the onset of structures with high stickiness that give rise to an effective barrier near the broken shearless curve. Moreover, we show how these stickiness structures, and the concomitant transport reduction in the shearless region, are determined by a homoclinic tangle of the remaining dominant twin island chains. We use the finite-time rotation number, a recently proposed diagnostic, to identify transport barriers that separate different regions of stickiness. The identified barriers are comparable to those obtained by using finite-time Lyapunov exponents.FAPESPCNPqCAPESMCT/CNEN (Rede Nacional de Fusao)Fundacao AraucariaUS Department of Energy DE-FG05-80ET-53088Physic

Enriched elderly virtual profiles by means of a multidimensional integrated assessment platform

The pressure over Healthcare systems is increasing in most developed countries. The generalized aging of the population is one of the main causes. This situation is even worse in underdeveloped, sparsely populated regions like Extremadura in Spain or Alentejo in Portugal. The authors propose to use the Situational-Context, a technique to seamlessly adapt Internet of Things systems to the needs and preferences of their users, for virtually modeling the elderly. These models could be used to enhance the elderly experience when using those kind of systems without raising the need for technical skills or the costs of implementing such systems by the regional healthcare systems. In this paper, the integration of a multidimensional integrated assessment platform with such virtual profiles is presented. The assessment platform provides and additional source of information for the virtual profiles that is used to better adapt existing systems to the elders needs

SDG9 and the competitiveness: Employing mixed methods to understand how countries can use science to compete

Policymakers seek the best ways to promote the development of their countries. With Agenda 2030 at the top of the conversation, this study aimed to analyze the relationship between SDG9 and GCI. The study uses two methodologies, the first of which uses panel data to explain how variables that make up SDG9 explain competitiveness across countries in the Eurozone from 2010 to 2019. A second approach is through qualitative methodology (fsQCA) to verify the differences in the possible combinations of variables for the same outcome – higher values of competitiveness. The findings suggest that R&D and patents are two factors that increase competitiveness. Additionally, the number of patents filed in each country is also considered a necessary condition for high GCI values, reinforcing the need for countries to protect their innovations. In conclusion, the variables of SDG9 show significant relationships to achieve high values of competitiveness and that there is not only one solution to achieve the outcome but several, and it is up to policymakers to define which strategy best fits their reality. The originality of the article lies in the way different methods are combined and the increased capacity to understand the reality that these different methods allow.info:eu-repo/semantics/publishedVersio