Dynamic Thermal Characteristics of Opaque Building Components. A Proposal for the Extension of EN ISO 13786

Abstract In order to dynamically characterise the opaque components of a building envelope subject to sinusoidal loadings in steady periodic regime conditions, the use of nondimensional periodic thermal transmittance is proposed. Such a parameter allows for the evaluation of the decrement factor and time lag that the heat flux undergoes while crossing the wall and the efficiency of the heat storage. For non-sinusoidal loadings, dynamic characterisation is obtained by the decrement factor, defined as the ratio between energy in a semi period entering the indoor environment and entering the wall and as the ratio between maximum heat fluxes entering the environment and the wall, and as the ratio between the minimum heat fluxes. These parameters allow to determine the heat storage capacity of the component, the maximum heat flux in summer and winter conditions and their time lags. The defined dynamic properties were calculated considering two commonly used walls and surrounding conditions that are representative of the effective operative conditions

Scaling of stiffness energy for 3d +/-J Ising spin glasses

Large numbers of ground states of 3d EA Ising spin glasses are calculated for sizes up to 10^3 using a combination of a genetic algorithm and Cluster-Exact Approximation. A detailed analysis shows that true ground states are obtained. The ground state stiffness (or domain wall) energy D is calculated. A D ~ L^t behavior with t=0.19(2) is found which strongly indicates that the 3d model has an equilibrium spin-glass-paramagnet transition for non-zero T_c.Comment: 4 pages, 4 figure

A Renormalization Proof of the KAM Theorem for Non-Analytic Perturbations

We shall use a Renormalization Group (RG) scheme in order to prove the classical KAM result in the case of a non-analytic perturbation (the latter will be assumed to have continuous derivatives up to a sufficiently large order). We shall proceed by solving a sequence of problems in which the perturbations are analytic approximations of the original one. We shall finally show that the sequence of the approximate solutions will converge to a differentiable solution of the original problem.Comment: 33 pages, no figure

Perspectives on using remotely-sensed imagery in predictive veterinary epidemiology and global early warning systems

Recent disease epidemics and their spread around the world have illustrated the weaknesses of disease surveillance and early warning systems (EWS), both at national and international levels. These diseases continuously threaten the livestock sector on a worldwide basis, some with major public health impact. EWS and accurate forecasting of new outbreaks of epidemic livestock diseases that may also affect wildlife, and the capacity for spread of such diseases to new areas is an essential pre-requisite to their effective containment and control. Because both the geographical and seasonal distribution of many infectious diseases are linked to climate, the possibility of using climaterelated environmental factors as predictive indicators, in association with regular disease surveillance activities, has proven to be relevant when establishing EWS for climate-related diseases. This article reviews the growing importance of using geographical information systems in predictive veterinary epidemiology and its integration into EWS, with a special focus on Rift Valley fever. It shows that, once fully validated in a country or region, this technology appears highly valuable and could play an increasing role in forecasting major epidemics, providing lead time to national veterinary services to take action to mitigate the impact of the disease in a cost-effective manner

Quality of experience and HTTP adaptive streaming: a review of subjective studies

HTTP adaptive streaming technology has become widely spread in multimedia services because of its ability to provide adaptation to characteristics of various viewing devices and dynamic network conditions. There are various studies targeting the optimization of adaptation strategy. However, in order to provide an optimal viewing experience to the end-user, it is crucial to get knowledge about the Quality of Experience (QoE) of different adaptation schemes. This paper overviews the state of the art concerning subjective evaluation of adaptive streaming QoE and highlights the challenges and open research questions related to QoE assessment