Scaling in a continuous time model for biological aging

In this paper we consider a generalization to the asexual version of the Penna model for biological aging, where we take a continuous time limit. The genotype associated to each individual is an interval of real numbers over which Dirac $\delta$--functions are defined, representing genetically programmed diseases to be switched on at defined ages of the individual life. We discuss two different continuous limits for the evolution equation and two different mutation protocols, to be implemented during reproduction. Exact stationary solutions are obtained and scaling properties are discussed.Comment: 10 pages, 6 figure

Desenvolvimento de sistema de consulta e visualização interativa de dados das projeções do IPCC AR4 para o Brasil.

Resumo: O objetivo deste trabalho foi desenvolver um sistema para busca e visualização de dados de variáveis climáticas projetados pelos modelos globais do Quatro Relatório (AR4) do IPCC para o Brasil. As informações são médias mensais de temperatura média, temperatura mínima, temperatura máxima, precipitação, umidade relativa e duração do período de molhamento foliar para os períodos de referência (1961-1990) e do futuro (2011-2040, 2041-2070, 2071-2100, cenários A2 e B1). O sistema iniciando com as opções do presente observado e dos cenários A2 e B1, permite uma busca por parâmetros como modelos climáticos globais, variáveis climáticas, período e mês. Os resultados das consultas são visualizados em uma grade com valores de longitude, latitude e variável climática. Com uma interface funcional, este sistema permite ao usuário a busca de dados climáticos de uma forma ágil e rápida, com apresentação dos dados organizados em um arquivo no formato ASCII (txt). Abstract: The aim of this study was to develop a system for searching and data visualization of climate variables projected by global climate models of the IPCC Fourth Assessment Report for Brazil. The variables are monthly average of mean temperature, minimum temperature, maximum temperature, precipitation, relative humidity, and duration of leaf wetness for the reference period (1961-1990) and future periods (2011-2040, 2041-2070, 2071 – 2100, A2 and B1 scenarios). The system allows the user to search for parameters, such as: global climate models, climatic variables, period, and month. The query results are displayed in a grid with values of longitude, latitude, and any climatic variable. With a functional interface, this system allows the user to search for climate data in an agile and quickly, with presentation of data in an ASCII file (txt) format

Mine water utilization as a secondary heat source and heat storage in a smart local heating and cooling distribution system

Mine water has been gaining increasing attention in recent years as a potential source for heat recovery and storage. This is due to its unique properties that make it an ideal medium for capturing and storing large amounts of thermal energy. Mine water is naturally heated by the earth's geothermal energy and typically has a constant temperature throughout the year, making it an excellent source of renewable energy. Additionally, the water's high thermal conductivity and large volumes provide an effective means for storing and transferring heat. With the increasing demand for sustainable energy sources and the need to reduce greenhouse gas emissions, the utilization of mine water for heat recovery and storage has become an attractive option for many industries and communities. In this project, we will explore the benefits of using mine water for heat recovery and storage, as well as some of the risks and challenges that need to be overcome to fully realize its potential as a renewable energy source

A Case Study of the Integration of Mine water into Smart Cooling and Heating Network systems

Minewater presents a significant opportunity as an energy source and store in the UK and elsewhere. This research investigates the feasibility and factors necessary to successfully integrate minewater into smart cooling and heating network systems that can support acceleration towards the UK’s net zero target. Heat recovery from minewater offers a lowcarbon source of energy for either heating or cooling and can provide thermal storage, potentially valuable for inter-seasonal demand. The work builds on a feasibility study in Barnsley, Yorkshire, which explored the design of a heat network that integrates heat, power, and mobility and uses waste heat from a glass factory. This work focusses on analyzing the subsurface factors including flowrate, yield, mine void volume, and interconnectivity, which affect the flow and consequently thermal behavior of the available minewater. A 3D model using Petrel and Groundhog have been created combining data from the available boreholes and Coal Authority maps to characterise the subsurface conditions

Nonadiabatic coherent evolution of two-level systems under spontaneous decay

In this paper we extend current perspectives in engineering reservoirs by producing a time-dependent master equation leading to a nonstationary superposition equilibrium state that can be nonadiabatically controlled by the system-reservoir parameters. Working with an ion trapped inside a nonindeal cavity we first engineer effective Hamiltonians that couple the electronic states of the ion with the cavity mode. Subsequently, two classes of decoherence-free evolution of the superposition of the ground and decaying excited levels are achieved: those with time-dependent azimuthal or polar angle. As an application, we generalise the purpose of an earlier study [Phys. Rev. Lett. 96, 150403 (2006)], showing how to observe the geometric phases acquired by the protected nonstationary states even under a nonadiabatic evolution.Comment: 5 pages, no figure

Semiclassical theory for small displacements

Characteristic functions contain complete information about all the moments of a classical distribution and the same holds for the Fourier transform of the Wigner function: a quantum characteristic function, or the chord function. However, knowledge of a finite number of moments does not allow for accurate determination of the chord function. For pure states this provides the overlap of the state with all its possible rigid translations (or displacements). We here present a semiclassical approximation of the chord function for large Bohr-quantized states, which is accurate right up to a caustic, beyond which the chord function becomes evanescent. It is verified to pick out blind spots, which are displacements for zero overlaps. These occur even for translations within a Planck area of the origin. We derive a simple approximation for the closest blind spots, depending on the Schroedinger covariance matrix, which is verified for Bohr-quantized states.Comment: 16 pages, 4 figures

Lattice Gas Analogue Of SK Model: A paradigm for the glass transition

We investigate the connection between the well known Sherrington-Kirkpatrick Ising Spin Glass and the corresponding Lattice Gas model by analyzing the relation between their thermodynamical functions. We present results of replica approach in the Replica Symmetric approximation and discuss its stability as a function of temperature and external source. Next we examine the effects of first order Replica Symmetry Breaking at zero temperature. We finally compare SK results with ours and suggest how the latter could be relevant to a description of the structural glass transition.Comment: 33 Pages, LaTeX file; 15 Figures added, some grammatical corrections. To appear in Journal of Physics