955 resultados para Passive-avoidance


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The aim of this contribution is to extend the techniques of composite materials design to non-linear material behaviour and apply it for design of new materials for passive vibration control. As a first step a computational tool allowing determination of macroscopic optimized one-dimensional isolator behaviour was developed. Voigt, Maxwell, standard and more complex material models can be implemented. Objective function considers minimization of the initial reaction and/or displacement peak as well as minimization of the steady-state amplitude of reaction and/or displacement. The complex stiffness approach is used to formulate the governing equations in an efficient way. Material stiffness parameters are assumed as non-linear functions of the displacement. The numerical solution is performed in the complex space. The steady-state solution in the complex space is obtained by an iterative process based on the shooting method which imposes the conditions of periodicity with respect to the known value of the period. Extension of the shooting method to the complex space is presented and verified. Non-linear behaviour of material parameters is then optimized by generic probabilistic meta-algorithm, simulated annealing. Dependence of the global optimum on several combinations of leading parameters of the simulated annealing procedure, like neighbourhood definition and annealing schedule, is also studied and analyzed. Procedure is programmed in MATLAB environment.

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It is imperative to accept that failures can and will occur, even in meticulously designed distributed systems, and design proper measures to counter those failures. Passive replication minimises resource consumption by only activating redundant replicas in case of failures, as typically providing and applying state updates is less resource demanding than requesting execution. However, most existing solutions for passive fault tolerance are usually designed and configured at design time, explicitly and statically identifying the most critical components and their number of replicas, lacking the needed flexibility to handle the runtime dynamics of distributed component-based embedded systems. This paper proposes a cost-effective adaptive fault tolerance solution with a significant lower overhead compared to a strict active redundancy-based approach, achieving a high error coverage with the minimum amount of redundancy. The activation of passive replicas is coordinated through a feedback-based coordination model that reduces the complexity of the needed interactions among components until a new collective global service solution is determined, improving the overall maintainability and robustness of the system.

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El reconocimiento temprano de anormalidades en la transferencia pasiva de inmunidad en equinos es importante para un manejo satisfactorio de los potrillos. La placenta de la yegua, epiteliocorial, no permite el pasaje de inmunoglobulinas.(Igs). La ingesta de calostro es vital ya que provee las Igs necesarias para alcanzar una concentración sérica de IgG mayor a 800 mg por ciento. Se considerara falla parcial con niveles de IgG entre 400 y 800 mgpor ciento; y total con niveles menores a 400 mg por ciento. La absorción de las Igs es máxima hasta 8 hs después del nacimiento y disminuye hasta hacerse nula a las 24 hs posparto. Los objetivos son: a) estudiar la cinética de la transferencia pasiva de Igs determinando la concentración de IgG sérica en potrillos en el primer trimestre de vida. b) relacionar la concentración de IgG del suero y calostro de la yegua con la concentración sérica de IgG en el potrillo. c) Relacionar en calostro la concentración de inmunoglobulina G con la densidad específica y la determinación semicuantitativa de inmunoglobulina G. d) Relacionar en el suero del potrillo a las 18 - 24 hs posparto la concentración de inmunoglobulina G con la densidad específica y la determinación semicuantitativa de inmunoglobulina G. Material y método: Diseño de estudio: de cohorte, observacional, descriptivo. Animales: 70 yeguas y 70 potrillos de raza Puro Polo. Calostros: 70 muestras Toma de muestras: Yeguas: se tomará una muestra de sangre en el periparto y una muestra de calostro posparto, antes del calostrado del potrillo. Potrillos: se tomarán muestras de sangre seriadas: al nacimiento (precalostrado), 6 hs posparto, 12 hs, 18 hs y 24 hs posparto y a los 21, 60 y 90 días posparto. Determinación de IgG (Suero y calostro): a) Técnica de inmunodifusión radial simple, los resultados se expresará en mg por ciento, en muestras seriadas en intervalos de tiempo preestablecidos. b)Refractometría (con refractómetro Modelo RHC-200/ATC- Arcano). c) Test de gluteralehído, Inmuno -G test. Análisis estadístico: Comparaciones de medias con prueba t apareada o de diferencia de medias, Se considera p significativa < 0,05. Se realizará un análisis de componentes principales. Se correlacionará la concentración de Ig G de suero y calostro de la yegua con la concentración en suero de potrillo. Con los resultados de este trabajo se determinarán los valores de inmunoglobulina en las yeguas y potrillos y su comportamiento en el tiempo, y se validará la sensibilidad y especificidad de las técnicas diagnósticas utilizadas. Los resultados permitirán obtener conocimientos para un manejo racional, desde la perspectiva inmunológica, de los potrillos, al establecer mediante técnicas cuantitativas y semicuantitativas los niveles de Igs séricos alcanzados, favoreciendo un diagnóstico precoz de inmunodeficiencia por fracaso de la transferencia de anticuerpos que pondría en riesgo la vida del potrillo.

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In Ireland the average energy cost for a household in 2006 was estimated to be €1,767, an increase of 4% on 2005 figures. With the state o f the current economic climate, home owners are beginning to realise the potential of energy efficient construction methods. The Passive House Standard offers a cost efficient and sustainable construction solution compared to the Traditional Irish construction methods. This report focuses on the Cost comparison between Passive House construction and traditional construction methods. The report also focuses on barriers that are slowing market penetration of the Passive House standard in the Irish Market. It also identifies potential energy savings that passive house occupants would benefit from. The report also highlights professional opinions on the future development o f the Passive House Standard in Ireland. The conclusions of this report are that the Passive House Standard is a more financially suitable construction solution compared to that o f a traditional dwelling complying with the Irish Building Regulations. The report also concludes that the Passive House Standard won’t be introduced as an Irish Building Regulation in the future but that it will have a big impact on future building regulations. The hypothesis o f this report is supported by data obtained from a literature review, qualitative data analysis and a case study. The report recommends that in order for the Passive House Standard to penetrate further into the Irish construction market, various barriers must be rectified. Local manufactures must start producing suitable components that suit the Passive House specification. The Building Energy Rating system must be altered in order for the Passive House to achieve its potential BER rating.

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Magdeburg, Univ., Fak. für Naturwiss., Diss., 2012

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PEEC, computational electromagnetics

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Magdeburg, Univ., Fak. für Naturwiss., Diss., 2010

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Otto-von-Guericke-Universität Magdeburg, Fakultät für Maschinenbau, Dissertation, 2016

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Inbreeding avoidance is predicted to induce sex biases in dispersal. But which sex should disperse? In polygynous species, females pay higher costs to inbreeding and thus might be expected to disperse more, but empirical evidence consistently reveals male biases. Here, we show that theoretical expectations change drastically if females are allowed to avoid inbreeding via kin recognition. At high inbreeding loads, females should prefer immigrants over residents, thereby boosting male dispersal. At lower inbreeding loads, by contrast, inclusive fitness benefits should induce females to prefer relatives, thereby promoting male philopatry. This result points to disruptive effects of sexual selection. The inbreeding load that females are ready to accept is surprisingly high. In absence of search costs, females should prefer related partners as long as delta<r/(1+r) where r is relatedness and delta is the fecundity loss relative to an outbred mating. This amounts to fitness losses up to one-fifth for a half-sib mating and one-third for a full-sib mating, which lie in the upper range of inbreeding depression values currently reported in natural populations. The observation of active inbreeding avoidance in a polygynous species thus suggests that inbreeding depression exceeds this threshold in the species under scrutiny or that inbred matings at least partly forfeit other mating opportunities for males. Our model also shows that female choosiness should decline rapidly with search costs, stemming from, for example, reproductive delays. Species under strong time constraints on reproduction should thus be tolerant of inbreeding.

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We have been able to produce a mouse monoclonal IgE antibody specific to an adult worm antigen extracted from Schistosoma japonicum (Sj). The antibody was able to elicit passive cutaneous anaphylaxis in the rat skin against Sj with the highest titer of 1:256,000 but did not cross-react with S. mansoni antigen. The antibody recognized a 97-kDa molecule expressed on the surface of mechanically transformed schistosoma of S. japonicum. Passive transfer of the antibody into mice in the early stage of challenge infection resulted in a partial but significant reduction of recovery of adult worms. Induction of eosinophilia by an oral administration of embryonated eggs of Toxocara canis prior to challenge infection enhanced the reduction.

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This paper develops a general theoretical framework within which a heterogeneous group taxpayers confront a market that supplies a variety of schemes for reducing tax liability, and uses this framework to explore the impact of a wide range of anti-avoidance policies. Schemes differ in their legal effectiveness and hence in the risks to which they expose taxpayers - risks which go beyond the risk of audit considered in the conventional literature on evasion. Given the individual taxpayer’s circumstances, the prices charged for the schemes and the policy environment, the model predicts (i) whether or not any given taxpayer will acquire a scheme, and (ii) if they do so, which type of scheme they will acquire. The paper then analyses how these decisions, and hence the tax gap, are influenced by four generic types of policy: Disclosure – earlier information leading to faster closure of loopholes; Penalties – introduction of penalties for failed avoidance; Policy Design – fundamental policy changes that design out opportunities for avoidance; Product Register - the introduction of GAARs or mini-GAARs that give greater clarity about how different types of scheme will be treated. The paper shows that when considering the indirect/behavioural effects of policies on the tax gap it is important to recognise that these operate on two different margins. First policies will have deterrence effects – their impact on the quantum of taxpayers choosing to acquire different types schemes as distinct to acquiring no scheme at all. There will be a range of such deterrence effects reflecting the range of schemes available in the market. But secondly, since different schemes generate different tax gaps, policies will also have switching effects as they induce taxpayers who previously acquired one type of scheme to acquire another. The first three types of policy generate positive deterrence effects but differ in the switching effects they produce. The fourth type of policy produces mixed deterrence effects.

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Game theorists typically assume that changing a game’s payoff levels—by adding the same constant to, or subtracting it from, all payoffs—should not affect behavior. While this invariance is an implication of the theory when payoffs mirror expected utilities, it is an empirical question when the “payoffs” are actually money amounts. In particular, if individuals treat monetary gains and losses differently, then payoff–level changes may matter when they result in positive payoffs becoming negative, or vice versa. We report the results of a human–subjects experiment designed to test for two types of loss avoidance: certain–loss avoidance (avoiding a strategy leading to a sure loss, in favor of an alternative that might lead to a gain) and possible–loss avoidance (avoiding a strategy leading to a possible loss, in favor of an alternative that leads to a sure gain). Subjects in the experiment play three versions of Stag Hunt, which are identical up to the level of payoffs, under a variety of treatments. We find differences in behavior across the three versions of Stag Hunt; these differences are hard to detect in the first round of play, but grow over time. When significant, the differences we find are in the direction predicted by certain– and possible–loss avoidance. Our results carry implications for games with multiple equilibria, and for theories that attempt to select among equilibria in such games.

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High Performance Computing is a rapidly evolving area of computer science which attends to solve complicated computational problems with the combination of computational nodes connected through high speed networks. This work concentrates on the networks problems that appear in such networks and specially focuses on the Deadlock problem that can decrease the efficiency of the communication or even destroy the balance and paralyze the network. Goal of this work is the Deadlock avoidance with the use of virtual channels, in the switches of the network where the problem appears. The deadlock avoidance assures that will not be loss of data inside network, having as result the increased latency of the served packets, due to the extra calculation that the switches have to make to apply the policy.