Initial correlation in a system of a spin coupled to a spin bath through an intermediate spin

The strong system-bath correlation is a typical initial condition in many condensed matter and some quantum optical systems. Here, the dynamics of a spin interacting with a spin bath through an intermediate spin are studied. Initial correlations between the spin and the intermediate spin are taken into account. The exact analytical expression for the evolution operator of the spin is found. Furthermore, correlated projection superoperator techniques are applied to the model and a time-convolutionless master equation to second order is derived. It is shown that the time-convolutionless master equation to second order reproduces the exact dynamics for time-scales of the order 1/{\gamma}, where {\gamma} is the coupling of the central spin to the intermediate spin. It is found that there is a strong dependence on the initial system-bath correlations in the dynamics of the reduced system, which cannot be neglected.Comment: 10 pages, 9 figures. arXiv admin note: text overlap with arXiv:0708.0410 by other author

L'argent, la famille, les amies : ethnographie contemporaine des tontines africaines en contexte migratoire

L'article aborde le versant féminin de l'immigration subsaharienne en France. Installées en France depuis les années 1980-1990, les femmes africaines perpétuent leurs pratiques économiques et en particulier celle des tontines, très dynamiques dans les banlieues parisiennes. Pour comprendre le phénomène, l'auteur, en se basant sur des observations de terrain menées au Sénégal et au Mali et sur l'apport des théoriciens du don, présente tout d'abord les aspects fondamentaux des pratiques de tontines à travers leur développement historique en Afrique de l'Ouest. Au terme d'une analyse comparative, elle montre comment, dans un contexte d'immigration, les tontines ont continué à satisfaire des besoins variés de sécurité, sociale et psychologique, pour les femmes immigrées en France. Elles correspondent à la mise en œuvre de stratégies féminines d'adaptation, qui questionnent l'organisation de l'économie au sein de la famille, les rapports de genres et de générations, en contexte migratoire

Stochastic wave-function unravelling of the generalized Lindblad equation

We investigate generalized non-Markovian stochastic Schroeodinger equations (SSEs), driven by a multidimensional counting process and multidimensional Brownian motion introduced by A. Barchielli and C. Pellegrini [J. Math. Phys. 51, 112104 (2010)]. We show, that these SSEs can be translated in a non-linear form, which can be efficiently simulated. The simulation is illustrated by the model of a two-level system in a structured bath and the results of the simulations are compared with the exact solution of the generalized master equation.Comment: 8 figure

Linguistic signatures of regulatory focus: How abstraction fits promotion more than prevention

In 3 experiments, the authors investigated how strategic inclinations associated with promotion versus prevention orientations - that is, eager approach versus vigilant avoidance, respectively - affect the use of language. It is hypothesized that eager promotion strategies used to attain desired end states entail using more abstract language than used with vigilant prevention strategies. This is shown to hold for experimentally induced relationship goals (Experiment 1) and communication goals (Experiment 2). In the 3rd experiment, the authors examined the impact of abstractly and concretely worded messages upon the behavioral intentions of chronically prevention- and promotion-oriented individuals and found support for the hypothesis that behavioral intentions to engage in specific activities are stronger when there is a fit between message wording and chronic orientation than when there is no fit. The broader implications of these findings are discussed. Copyright 2005 by the American Psychological Association

Practices of forest exploitation in priority investment projects: Benefits and implications

The paper discusses the topical issues of investment activities enhancement in the forest sector of the Russian economy by implementing the mechanism of priority investment projects in the field of forest exploitation - economic model of public-private partnership proposed by the forest owner (the State) for the private sector. The aim of the considered investment projects is the development of a timber-processing infrastructure, which is reliably provided with wood raw materials. It becomes possible to ensure certain preferences for businessmen that encourage them to invest money into the forest sector. Thus, the other objective is to develop recommendations for attracting investments into the forest sector of the Russian economy in the framework of priority investment projects. The paper analyzes a ten-year experience in the practice of applying priority investment projects in forest exploitation using an integrated approach to studying project management issues and method of comparison. The research identifies positive moments and a number of organizational and methodological shortcomings related to the development and implementation of investment projects in the forest sector of the Russian Federation. A number of areas contributing to the development of investment activities in forest exploitation is proposed. © Published under licence by IOP Publishing Ltd

When a thin periodic layer meets corners: asymptotic analysis of a singular Poisson problem

The present work deals with the resolution of the Poisson equation in a bounded domain made of a thin and periodic layer of finite length placed into a homogeneous medium. We provide and justify a high order asymptotic expansion which takes into account the boundary layer effect occurring in the vicinity of the periodic layer as well as the corner singularities appearing in the neighborhood of the extremities of the layer. Our approach combines the method of matched asymptotic expansions and the method of periodic surface homogenization, and a complete justification is included in the paper or its appendix.Comment: 58 page

Warm-Cool Emotions of LED Lightings around 5,000K

In this study, warm-cool feelings of near-white lightings were investigated after the subjects??? eyes being adapted to 5,000K. The psychophysical experiment was carried out in a dark room using 5 channels LED lighting booth. In the experiment, total of 48 test lightings around 5,000K were generated using the booth. Total of 20 subjects evaluated warm-cool feelings of each test lighting. The results showed that lower CCT tended to have ???Warm??? feeling, while higher CCT tended to arouse ???Cool??? feeling. When CIECAM02 H is in the range of 0-100 and 380-400, ???Warm??? feeling was strongly evoked and when H is in the range of 250-300, ???Cool??? feeling was strongly aroused. Also, when test lightings have same hue, the one having higher chroma aroused stronger feeling on either ???Warm??? or ???Cool???. Emotion model test results showed Koo???s model, which is based on lighting colors, showed better performance than the model developed based on color patches