925 resultados para Multilevel Systems Model


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A neural network theory of :3-D vision, called FACADE Theory, is described. The theory proposes a solution of the classical figure-ground problem for biological vision. It does so by suggesting how boundary representations and surface representations are formed within a Boundary Contour System (BCS) and a Feature Contour System (FCS). The BCS and FCS interact reciprocally to form 3-D boundary and surface representations that arc mutually consistent. Their interactions generate 3-D percepts wherein occluding and occluded object completed, and grouped. The theory clarifies how preattentive processes of 3-D perception and figure-ground separation interact reciprocally with attentive processes of spatial localization, object recognition, and visual search. A new theory of stereopsis is proposed that predicts how cells sensitive to multiple spatial frequencies, disparities, and orientations are combined by context-sensitive filtering, competition, and cooperation to form coherent BCS boundary segmentations. Several factors contribute to figure-ground pop-out, including: boundary contrast between spatially contiguous boundaries, whether due to scenic differences in luminance, color, spatial frequency, or disparity; partially ordered interactions from larger spatial scales and disparities to smaller scales and disparities; and surface filling-in restricted to regions surrounded by a connected boundary. Phenomena such as 3-D pop-out from a 2-D picture, DaVinci stereopsis, a 3-D neon color spreading, completion of partially occluded objects, and figure-ground reversals are analysed. The BCS and FCS sub-systems model aspects of how the two parvocellular cortical processing streams that join the Lateral Geniculate Nucleus to prestriate cortical area V4 interact to generate a multiplexed representation of Form-And-Color-And-Depth, or FACADE, within area V4. Area V4 is suggested to support figure-ground separation and to interact. with cortical mechanisms of spatial attention, attentive objcect learning, and visual search. Adaptive Resonance Theory (ART) mechanisms model aspects of how prestriate visual cortex interacts reciprocally with a visual object recognition system in inferotemporal cortex (IT) for purposes of attentive object learning and categorization. Object attention mechanisms of the What cortical processing stream through IT cortex are distinguished from spatial attention mechanisms of the Where cortical processing stream through parietal cortex. Parvocellular BCS and FCS signals interact with the model What stream. Parvocellular FCS and magnocellular Motion BCS signals interact with the model Where stream. Reciprocal interactions between these visual, What, and Where mechanisms arc used to discuss data about visual search and saccadic eye movements, including fast search of conjunctive targets, search of 3-D surfaces, selective search of like-colored targets, attentive tracking of multi-element groupings, and recursive search of simultaneously presented targets.

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Countries across the world are being challenged to decarbonise their energy systems in response to diminishing fossil fuel reserves, rising GHG emissions and the dangerous threat of climate change. There has been a renewed interest in energy efficiency, renewable energy and low carbon energy as policy‐makers seek to identify and put in place the most robust sustainable energy system that can address this challenge. This thesis seeks to improve the evidence base underpinning energy policy decisions in Ireland with a particular focus on natural gas, which in 2011 grew to have a 30% share of Ireland’s TPER. Natural gas is used in all sectors of the Irish economy and is seen by many as a transition fuel to a low-carbon energy system; it is also a uniquely excellent source of data for many aspects of energy consumption. A detailed decomposition analysis of natural gas consumption in the residential sector quantifies many of the structural drives of change, with activity (R2 = 0.97) and intensity (R2 = 0.69) being the best explainers of changing gas demand. The 2002 residential building regulations are subject to an ex-post evaluation, which using empirical data finds a 44 ±9.5% shortfall in expected energy savings as well as a 13±1.6% level of non-compliance. A detailed energy demand model of the entire Irish energy system is presented together with scenario analysis of a large number of energy efficiency policies, which show an aggregate reduction in TFC of 8.9% compared to a reference scenario. The role for natural gas as a transition fuel over a long time horizon (2005-2050) is analysed using an energy systems model and a decomposition analysis, which shows the contribution of fuel switching to natural gas to be worth 12 percentage points of an overall 80% reduction in CO2 emissions. Finally, an analysis of the potential for CCS in Ireland finds gas CCS to be more robust than coal CCS for changes in fuel prices, capital costs and emissions reduction and the cost optimal location for a gas CCS plant in Ireland is found to be in Cork with sequestration in the depleted gas field of Kinsale.

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We present results for a variety of Monte Carlo annealing approaches, both classical and quantum, benchmarked against one another for the textbook optimization exercise of a simple one-dimensional double well. In classical (thermal) annealing, the dependence upon the move chosen in a Metropolis scheme is studied and correlated with the spectrum of the associated Markov transition matrix. In quantum annealing, the path integral Monte Carlo approach is found to yield nontrivial sampling difficulties associated with the tunneling between the two wells. The choice of fictitious quantum kinetic energy is also addressed. We find that a "relativistic" kinetic energy form, leading to a higher probability of long real-space jumps, can be considerably more effective than the standard nonrelativistic one.

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We investigate the basic behavior and performance of simulated quantum annealing (QA) in comparison with classical annealing (CA). Three simple one-dimensional case study systems are considered: namely, a parabolic well, a double well, and a curved washboard. The time-dependent Schrodinger evolution in either real or imaginary time describing QA is contrasted with the Fokker-Planck evolution of CA. The asymptotic decrease of excess energy with annealing time is studied in each case, and the reasons for differences are examined and discussed. The Huse-Fisher classical power law of double-well CA is replaced with a different power law in QA. The multiwell washboard problem studied in CA by Shinomoto and Kabashima and leading classically to a logarithmic annealing even in the absence of disorder turns to a power-law behavior when annealed with QA. The crucial role of disorder and localization is briefly discussed.

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O presente trabalho pretende auxiliar o processo de consolidação do conceito de sustentabilidade no seio das organizações. Partindo de ferramentas de gestão e avaliação já existentes, esta tese sugere a sua integração numa única metodologia, ultrapassando desse modo as limitações e potenciando as suas capacidades enquanto ferramentas isoladas. O modelo proposto para o Sistema de Gestão da Sustentabilidade (SGS) integra assim: o conceito de melhoria contínua característico dos sistemas de gestão normalizados; a capacidade de tradução da perspetiva estratégica da gestão para o plano operacional, característica do Business Scorecard (BSC); e, por fim, a avaliação emergética é ainda utilizada como uma ferramenta de avaliação da sustentabilidade de sistemas. Um objetivo secundário desta tese prende-se com o desenvolvimento de um procedimento para a realização da análise emergética de um sistema. Depois de analisada a literatura referente à utilização da análise emergética, identificou-se como necessária a definição de um procedimento normalizado, adotando um conjunto de tarefas e um formato de apresentação de resultados que permita disseminar o conceito e tornar a ferramenta mais “utilizável”. Por outro lado, procurou-se dotar o procedimento com um conjunto de indicações que permitem ultrapassar limitações e inconvenientes apontados pelos críticos mas também utilizadores do método, nomeadamente: problemas de dupla contagem, cálculo da incerteza da análise e critérios de qualidade da informação utilizada. O modelo dos sistemas de gestão normalizados apresenta um papel central na metodologia proposta. O conceito de “melhoria contínua” afigura-se como fundamental num sistema que pretende implementar o conceito “desenvolvimento sustentável” e avaliar o seu desempenho à luz do mesmo. Assim, o ciclo Plan-Do-check-Act (PDCA) deve ser utilizado para implementar o SGS de acordo com uma Política para a Sustentabilidade que a organização deve desenvolver. Definida a Política, o modelo baseia-se então no ciclo PDCA: fase de planeamento; fase de implementação; fase de verificação; e fase de revisão. É na fase de planeamento do SGS que se sugere a introdução das outras duas ferramentas: a análise emergética (AEm) e o BSC. A fase de planeamento do modelo de SGS proposto neste trabalho foi aplicada à Universidade de Aveiro (UA), incluindo a definição de uma Política para a Sustentabilidade e o planeamento estratégico e operacional. A avaliação emergética à UA foi realizada recorrendo ao procedimento desenvolvido nesta tese e permitiu caracterizar e avaliar os fluxos de recursos que a “alimentam” sob uma só unidade, atribuindo deste modo graus de importância aos diferentes recursos utilizados. A informação representa 96% do total de recursos utilizados na UA, quando avaliados sob o ponto de vista emergética. Para além da informação, os fluxos financeiros representam a maior fatia do orçamento emergético da UA, grande parte dos quais serve para sustentar os serviços prestados pelo corpo docente da UA. Analisando valores históricos de 3 indicadores de desempenho emergético, observa-se que a UA não regista uma evolução positiva em nenhum dos indicadores: a emergia utilizada nos edifícios tem-se mantido mais ou menos constante; a retribuição emergética da UA para a sociedade, avaliada sobre a forma de diplomados, tem diminuído; e a relação emergética entre professores e alunos tem também diminuído, facto que pode refletir-se na qualidade dos “produtos” da UA. Da aplicação do SGS à UA regista-se: a adequabilidade do ciclo PDCA à implementação de um SGS; a capacidade da AEm “obrigar” a organização a adotar uma abordagem sistémica da sua atividade, resultando numa visão mais aprofundada da sua relação com o contexto ambiental, económico e social em que se insere; a importância da visão estratégica e da sua tradução em termos operacionais na fase de planeamento de um SGS; e, por fim, a capacidade de adaptação e dupla funcionalidade (implementação e avaliação) do modelo de SGS proposto. A metodologia de SGS proposta nesta tese, sendo direcionada para todo o tipo de organizações, não se desvirtua quando aplicada ao contexto específico das instituições de ensino superior e permite implementar e avaliar o conceito “desenvolvimento sustentável” nas quatro dimensões da universidade (Educação, Investigação, Operação; Relação com as partes interessadas).

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Empirical research has consistently demonstrated a positive association between psychopathic traits and physical aggression (Campbell, Porter, & Santor, 2004; Gretton, Hare, & Catchpole, 2004; Raine et aI., 2006; Spain, Douglas, Poythress, & Epstein, 2004). Moreover, research has also found that the emotional/interpersonal (Factor 1) psychopathy traits tend to be more closely associated with goal oriented, proactive aggression, whereas the social deviance (Factor 2) psychopathy characteristics have been more closely linked to reactive aggression, which is perpetrated in response to threat or provocation (Flight & Forth, 2007). Blair (2004; 2005; 2006) has recently proposed the Integrated Emotions Systems Model (lES), which posits that the association between Factor 1 psychopathy traits and proactive aggression is due to amygdala dysfunction leading to failed moral socialization. Consequently, individuals who exhibit Factor 1 psychopathy traits do not experience affective empathy in response to distress cues exhibited by others, thus, preventing the inhibition of proactive aggression. The current investigation sought to test this model by examining the associations among the emotional/interpersonal (Factor 1) psychopathy traits, proactive aggression, and affective empathy. After accounting for head injury, Factor 2 psychopathy traits, reactive aggression, and cognitive empathy, it was hypothesized that 1) Factor 1 psychopathy traits would predict proactive aggression, and 2) that affective empathy is a common cause of Factor 1 psychopathy traits, proactive aggression, and of the relationship between these two constructs. This hypothesis assumed that (a) affective empathy would uniquely predict Factor 1 psychopathy traits, (b) that affective empathy would uniquely predict proactive aggression, and (c) that affective empathy would account for the relationship between Factor I psychopathy traits and proactive aggression. The total sample consisted of 137 male undergraduate students. Participants completed measures of psychopathy (SRP III; Paulhus, Hemphill, & Hare, in press), aggression (PCS; Marsee, Kimonis, & Frick, 2004; RPQ; Raine et at, 2006), dispositional cognitive and affective empathy (BES; Jolliffe & Farrington, 2006; TES; Spreng, McKinnon, Mar, & Levine, 2009), and situational cognitive and affective empathy in response to neutral and empathy eliciting video clips. Physiological indices (heart rate & electrodermal activity) of affective empathy were also obtained while participants viewed the neutral and empathy eliciting videos. Findings indicated that Factor I psychopathy traits predicted proactive aggression. In addition, results demonstrated that affective empathy predicted both Factor I psychopathy traits and proactive aggression. However, the association between affective empathy and proactive aggression appeared to be dependent on the conceptualization and measurement of affective empathy. Conversely, affective empathy did not appear to account for the relationship between Factor I psychopathy traits and proactive aggression. Overall, results demonstrated partial support for the IES model. Implications of the results, limitations of the study and future research directions are discussed.

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La littérature montre que les résultats scolaires ne sont pas seulement imputables aux caractéristiques individuelles et familiales des élèves, mais qu’ils sont également influencés par l’établissement scolaire fréquenté. Utilisant une analyse multiniveaux comprenant deux niveaux hiérarchiques, soit l’élève et l’école, la présente recherche vise à démontrer l’impact du climat scolaire sur les résultats des élèves du secondaire. Dans ce contexte, le climat scolaire perçu est mesuré à partir de six indicateurs de perception mesurés à l’aide du Questionnaire sur l’Environnement Socioéducatif (QES) (Janosz, 2000). Les indicateurs utilisés pour rendre compte de l’effet-établissement sont ces indicateurs de climat scolaire agrégés par école. Les analyses ont été effectuées sur un échantillon transversal de 54 écoles publiques, parmi lesquelles 30 685 élèves âgés de 13 à 17 ans ont complété le questionnaire. Les résultats de l’analyse permettent de constater d’une part, que le climat scolaire influence bel et bien la réussite des élèves et d’autre part, qu’il est possible de différencier l’effet du climat perçu selon qu’il se situe au niveau de l’élève ou qu’il soit plutôt agrégé au niveau de l’école. À cet effet, seul le climat agrégé, plus particulièrement les climats éducatif et d’appartenance, permet d’expliquer les différences entre les écoles sur la base des résultats scolaires en français et en mathématiques.

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Los resultados financieros de las organizaciones son objeto de estudio y análisis permanente, predecir sus comportamientos es una tarea permanente de empresarios, inversionistas, analistas y académicos. En el presente trabajo se explora el impacto del tamaño de los activos (valor total de los activos) en la cuenta de resultados operativos y netos, analizando inicialmente la relación entre dichas variables con indicadores tradicionales del análisis financiero como es el caso de la rentabilidad operativa y neta y con elementos de estadística descriptiva que permiten calificar los datos utilizados como lineales o no lineales. Descubriendo posteriormente que los resultados financieros de las empresas vigiladas por la Superintendencia de Sociedades para el año 2012, tienen un comportamiento no lineal, de esta manera se procede a analizar la relación de los activos y los resultados con la utilización de espacios de fase y análisis de recurrencia, herramientas útiles para sistemas caóticos y complejos. Para el desarrollo de la investigación y la revisión de la relación entre las variables de activos y resultados financieros se tomó como fuente de información los reportes financieros del cierre del año 2012 de la Superintendencia de Sociedades (Superintendencia de Sociedades, 2012).

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identificar los factores que influyen en el desarrollo exitoso de empresas que produzcan software en Colombia y qué dirección se les debe dar a estos, con el fin de orientar las actividades empresariales y gubernamentales hacia la generación de una estructura que facilite la creación y desarrollo de empresas de base tecnológica del sector.

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INTRODUCCIÓN. El ultrasonido es fundamental en la medicina de emergencias, no se conoce cual debería ser la curva de aprendizaje para obtener las competencias técnicas y operativas; ACEP recomienda por cada ventana ecográfica realizar 25 repeticiones. No existe una curva de aprendizaje para ventana de VCI en la población de residentes colombianos. OBJETIVO: Determinar la curva de aprendizaje necesaria para obtener una proporción mayor al 80% de éxitos en la toma de la ventana ecográfica de la VCI, usando la escala de calificación para el aseguramiento de la calidad sugerida por ACEP, en residentes de I a III año de medicina de emergencias. METODOLOGÍA: Estudio experimental no comparativo, que evaluó la proporción de éxito en función del las tomas repetidas de la VCI por ultrasonido, mediciones que se tomaron luego de participar en una capacitación teórica y demostrativa de la técnica propuesta; se calificaron los videos según la escala publicada por ACEP. El análisis estadístico se realizó con un modelo logístico multinivel para la proporción del éxito, agrupado por repetición y agrupado por sujeto. RESULTADOS: Se obtuvo información de 8 residentes, cada uno realizo 25 repeticiones a 3 modelos sanos con asignación aleatoria. Se realizó la curva de aprendizaje obteniendo en 11 repeticiones una proporción de 0.80 (rango 0.54 a 0.92) y en 21 repeticiones una proporción de 0.9 (rango 0.75 a 0.96), datos ajustados por numero de repetición y residente. CONCLUSIÓN: La curva de aprendizaje para la ventana ecográfica de la VCI es de 11 y 21 repeticiones para obtener el 80% y 90% de éxito en residentes de medicina de emergencias de I a III año de la universidad del rosario.

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Desde la noción universal sobre la empresa como un sistema de interacción con un entorno determinado para alcanzar un objetivo, de manera planificada y en función de satisfacer las demandas de un mercado mediante la actividad económica, su viabilidad, sostenibilidad y crecimiento dependerán, por supuesto, de una serie de estrategias adecuadas no solo para tales fines, sino también para enfrentar diversidad de agentes endógenos y exógenos que puedan afectar el normal desempeño de su gestión. Estamos hablando de la importancia de la resiliencia organizacional y del Capital Psicológico. En un escenario tan impredecible como el de la economía mundial, donde la constante son los cambios en su comportamiento —unos propios de su dinámica e interdependencia, naturales de fenómenos como la globalización, y otros derivados de eventos disruptivos— hoy más que nunca es necesario implementar el modelo de la empresa resiliente, que es aquella entidad capaz de adaptarse y recuperarse frente a una perturbación. Al mismo tiempo, más allá de su tamaño, naturaleza u objeto social, es indispensable reconocer básicamente que toda organización está constituida por personas, lo cual implica la trascendencia que para su funcionamiento tiene el factor humano-dependiente, y por lo tanto se crea la necesidad de promover el Capital Psicológico y la resiliencia a nivel de las organizaciones a través de una cultura empresarial.

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La construcción es una de las industrias que mayores accidentes laborales genera, en esta investigación se realizó un análisis retrospectivo para determinar si existe alguna relación entre la ocurrencia de accidentes y la fecha de entrega de una meta, debido al incremento en la cantidad de trabajo expresado por la cantidad de días y horas extras trabajados, se cuenta con información de la accidentalidad de cinco empresas constructoras de un gran proyecto vial en Colombia en los años de 2012 y 2013. Se analizó la información correspondiente a la nómina de las mismas empresas, con el valor de la nómina mensual, el valor de las incapacidades mensuales y la cantidad de trabajadores por cada empresa en cada periodo. El manejo de los datos se hizo con EXCEL y el análisis estadístico con STATA 11.1, se usó la correlación de Spearman para encontrar la relación entre la cantidad de accidentes acumulados y: la cantidad acumulada de días trabajados en cada mes, la cantidad acumulada de horas extras trabajadas mensualmente y el costo acumulado en porcentaje de la nómina mensual, encontrándose en todos los casos una relación lineal. Por otra parte, se realizó una prueba binomial para establecer la relación de la fecha de entrega de la meta con la accidentalidad 30 días antes y después, encontrando que la accidentalidad aumenta en la proximidad previa a la entrega de la meta

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The paper focuses on the question of local development and applies the local territorial systems model to the urban area of Manresa (Barcelona). The concept of local development is discussed first, as well as the change in place's position within the network derived from metropolitan expansion processes. The role of Manresa's social agents and its development policies are explained, to stress the relevance of the position of places in the network and, foremost, of the role and capability of local actors in putting into value theirs milieu's resources

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The search for rocky exoplanets plays an important role in our quest for extra-terrestrial life. Here, we discuss the extreme physical properties possible for the first characterised rocky super-Earth, CoRoT-7b (R(pl) = 1.58 +/- 0.10 R(Earth), M(pl) = 6.9 +/- 1.2 M(Earth)). It is extremely close to its star (a = 0.0171 AU = 4.48 R(st)), with its spin and orbital rotation likely synchronised. The comparison of its location in the (M(pl), R(pl)) plane with the predictions of planetary models for different compositions points to an Earth-like composition, even if the error bars of the measured quantities and the partial degeneracy of the models prevent a definitive conclusion. The proximity to its star provides an additional constraint on the model. It implies a high extreme-UV flux and particle wind, and the corresponding efficient erosion of the planetary atmosphere especially for volatile species including water. Consequently, we make the working hypothesis that the planet is rocky with no volatiles in its atmosphere, and derive the physical properties that result. As a consequence, the atmosphere is made of rocky vapours with a very low pressure (P <= 1.5 Pa), no cloud can be sustained, and no thermalisation of the planet is expected. The dayside is very hot (2474 +/- 71 K at the sub-stellar point) while the nightside is very cold (50-75 K). The sub-stellar point is as hot as the tungsten filament of an incandescent bulb, resulting in the melting and distillation of silicate rocks and the formation of a lava ocean. These possible features of CoRoT-7b could be common to many small and hot planets, including the recently discovered Kepler-10b. They define a new class of objects that we propose to name ""Lava-ocean planets"". (C) 2011 Elsevier Inc. All rights reserved.

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We analyze a threshold contact process on a square lattice in which particles are created on empty sites with at least two neighboring particles and are annihilated spontaneously. We show by means of Monte Carlo simulations that the process undergoes a discontinuous phase transition at a definite value of the annihilation parameter, in accordance with the Gibbs phase rule, and that the discontinuous transition exhibits critical behavior. The simulations were performed by using boundary conditions in which the sites of the border of the lattice are permanently occupied by particles.