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Unsteady large-scale vortices, formed by the roll-up of free shear layers separating along sharp edges, are the dominant flow characteristics of the turbulent flow over buildings. These vortical structures interact with each other and with the building surface resulting in secondary separation and severe pressure fluctuations. Moreover, the interaction of the large-scale vortices with the multiplicity of turbulence scales in the incoming wind exacerbates their unsteady motion and hence significantly affects the pressure fluctuations spectra experienced by the building. Large-eddy simulations are conducted to study the interaction of homogeneous turbulence in the incident flow with a surface-mounted prism. A compact fifth-order upwind difference scheme is used to effectively and accurately perform the simulations. Three cases of incident flow are considered. In one case, the prism is placed in a smooth uniform flow. In the second case, homogeneous isotropic turbulence with von Karman spectrum is superimposed on the uniform flow at the inflow boundary. The integral length scale is one-half the prism height. In the third case, the integral length scale is equal to the prism height. The numerical results are compared with experimental measurements reported by Tieleman et al. (2002). The results show that the highest negative mean value of the pressure coefficient on the roof and the sides is about 30% larger in case two of turbulent inflow and takes place closer to the windward edge of the prism. Moreover, the pressure coefficients on the roof and sides of the prism in the case of turbulent inflow show a higher level of variations in comparison with the case of smooth inflow conditions. The predicted mean characteristics of the pressure coefficients in the turbulent case match the experimental values in terms of both magnitude and location on the roof of the prism reported in Tieleman et al. (1998) and Tieleman et al. (2002). As for the peak value, the peak value of -2 obtained in the turbulent inflow case two is about 20% smaller than the values measured experimentally by Tieleman et al. (2002). On the other hand, it is stressed that the peak value in the simulations would increase as the duration of the simulation is increased to match that of the experimental measurement. The results also show that the turbulent case yields a non-exceedence probability for the peak pressure coefficient that is closer to the one obtained from the measured data than the smooth case data. Also, spectral and cross-spectral analysis are carried out using complex Morlet wavelet transform to investigate pressure-velocity relation. The study shows that the nonlinearity in the relationship of velocity-pressure is detected using wavelet bicoherence. / Ph. D.

Free-fall penetrometers (FFPs) are an attractive tool for the rapid characterization of sediments in the nearshore and coastal areas. To improve their measurement capabilities, modern FFPs can be equipped with pore pressure sensors. Pore pressure measurements are extensively used in traditional cone penetration testing, but their usage and interpretation is still limited for FFP testing. This thesis represents an effort to advance the interpretation of pore pressure measurements from FFP testing. Data was collected using the torpedo-shaped FFP BlueDrop during surveys at Herschel Island, YT, Yakutat, AK, Clay Bank, VA, and Yorktown, VA. Additionally, test deployments in the laboratory were performed in kaolin clay. Data analysis was focused on pore pressure measurements during these deployments. Two major advancements regarding current data analysis of FFP pore pressure measurements were explored: 1) a method based on fluid dynamic principles was proposed to correct the pressure recordings for the dynamic flow effects due to the high-velocity fall and impact. The results show that using Bernoulli’s theorem coupled with the concept of pressure coefficients results in good agreement between measured and hydrostatic pressures during the free-fall and initial penetration stage. 2) Pore pressure dissipation curves measured by the penetrometer at rest at maximum penetration depth were also studied. The mechanisms behind the non-standard dissipation curves were explored. The results suggest that non-standard dissipation curves can be interpreted by correcting according to Sully et al.’s (1999) extrapolation technique. The technique can also be used with data from an unsaturated or clogged filter. / Master of Science

Previous research has shown that appearance-related pressures from multiple sources can influence body esteem in emerging adults. Furthermore, research has shown that self-compassion and gender play a role in body image and the relation between sociocultural pressures and body esteem. Less research has examined how these variables interact in their association with body esteem in emerging adults. Thus, the current study sought to assess these interactions. Participants (N = 877; 492 women) were primarily White (78.9% for women and 76.4% for men) and ranged in age from 18 to 28 (M = 18.70 for women and 19.10 for men). Participants completed an online survey with measures assessing appearance-related pressures, self-compassion, and body esteem. Results indicated a significant main effect of appearance-pressure from mothers on weight body esteem in women and a significant interaction of maternal appearance-related pressure and self-compassion on appearance body esteem in men.

Une forte croissance économique en Chine et son rôle important dans le commerce mondial impliquent que nous devons analyser son inflation avec les pressions intérieures et extérieures. Tandis que les papiers récents ont concentrés leur travail sur les processus d'inflation en Chine en utilisant des données nationales (voir, par exemple Brandt et Zhu, 2000; Feyzioglu & Willard, 2006; Porter, 2010), très peu d'attention a été mise sur l'inflation entre les différentes juridictions Chinoises. Ainsi, la compréhension de la dynamique de l'inflation et ses interactions entre les juridictions Chinoise sont des questions importantes pour les décisions des banques centrales en matière de politique monétaire. Dans ma thèse, tout d'abord, en considérant les pressions intérieures et extérieures de l'inflation, j'analyse les dynamiques de l'inflation entre les juridictions Chinoises (Chapitre 3). Ensuite, grâce à la libre circulation des biens et les migrations intérieures en Chine, je m'intéresse aux effets d'interactions de l'inflation à travers le pays avec les pressions intérieures et extérieures (Chapitre 4). Enfin, nous conjuguons la variation provinciale dans la dynamique de l'inflation Chinoise et les caractéristiques d'économie ouverte en estimant la courbe de Phillips hybride dans l'économie ouverte pour les provinces chinoises (Chapitre 5). / China's swift economic development and share in global trade increasing rapidly imply a need to understand its inflation dynamics with internal and external pressures. While recent papers focus on inflation process analysis in the mainland of China by using a country-level data (see, e.g. Brandt & Zhu, 2000; Feyzioğlu & Willard, 2006; Porter, 2010), less attention has been paid to differences across China's jurisdictions. Thus, understanding of inflation dynamics and its interaction among the Chinese provinces are the important issues for central bank's monetary policy decisions. Firstly, considering the internal and external inflation pressures, I analyze the inflation dynamics among the CMU (Chapter 3). Secondly, because of the free flow of goods and internal migration across the country, I'm interested in analyzing the effect of inflation interaction among its provinces with internal and external pressures (Chapter 4). Finally, we combine the interest in the provincial variation in China's inflation dynamics with its characteristic of economic openness by estimating hybrid open-economy Phillips curves for the Chinese provinces(Chapter 5).

A new approach is developed for evaluating the mixing properties of binary solutions at high pressure. This involves solving Poisson's equation throughout three-dimensional cubic lattices, consistent with Thomas-Fermi-Dirac (TFD) theory. Zero temperature calculations are carried out for a variety of compositions and crystal structures in 3 pressure groups relevant to Jovian planetary interiors. Pseudopotentials based on the two-component-plasma model (with a uniform electron background) are fitted to the solid-state results, and are then used in liquid-state calculations using hard-sphere perturbation theory. TFD results for H-He solutions find critical temperatures (above which all compositions are soluble) to be ∿ 0, 500, and 1500°K at pressures of 10, 100, and 1000 Mbar, respectively. These temperatures are much lower than those obtained using free electron perturbation theory, where T(crit) ∿ 10,000°K at 10 Mbar. Thus, unlike the perturbation theory results, the TFD results predict that helium should be soluble in metallic hydrogen in the deep interiors of both Jupiter and Saturn, and our calculations give an indication of the degree of model-dependence in computing high pressure mixing properties. In addition, TFD calculations for H-C and H-O solutions find phase separation temperatures to be≲ 10⁴ °K for pressures ≲ 10³ Mbar. These temperatures are considerably lower than those found assuming a uniform electron distribution (where T(crit) ≳ 10⁵ °K), and suggest that H-C and H-O solutions should also be miscible in the metallic zones of Jupiter and Saturn.

L’objet de ce travail de recherche est de contribuer à l’étude du concept de Performance Sociétale de l’Entreprise (PSE), dont les problématisations jusqu’à présent fournies demeurent largement controversées. En effet, l’examen du corpus de connaissances révèle l’existence d’anomalies de nature théorique, conceptuelle et empirique. Ces insuffisances renvoient aux modes d’opérationnalisation de la PSE, à la manière dont le concept a été relié à la notion de performance, ainsi qu’à l’absence de contextualisation de la PSE en rapport avec son environnement institutionnel. Il importe donc de réorganiser le concept au sein d’un cadre d’analyse consensuel qui reconnaît le caractère dynamique et contingent de la démarche sociétale de l’entreprise. Ainsi, ce travail se propose d’explorer le concept de PSE et d’analyser ses antécédents institutionnels et ses effets sur le niveau de performance organisationnelle.Sur le plan théorique, l’architecture globale de la thèse obéit à un raisonnement à triple phase : déconstruction/reconstruction/validation. La phase de déconstruction (première partie) se traduit par une mise en perspective critique (théorique, conceptuelle et empirique) de la PSE. La phase de reconstruction (deuxième partie) consiste en le développement d’un cadre d’analyse systémique qui se veut être fédérateur et englobant des différentes orientations théoriques. Et enfin, la phase de validation (troisième partie) est destinée à statuer sur les dépendances étudiées et la recevabilité des hypothèses, de manière à tirer un certain nombre de conclusions et d’enseignements.Sur le plan conceptuel, notre cadre d’analyse mobilise l’approche systémique pour décliner les différents niveaux d’analyse, à savoir, les pressions institutionnelles en tant qu’entrée du système, la PSE en tant que processus, et la performance organisationnelle en tant que résultat du système. Le modèle de recherche est articulé par un corps d’hypothèses multi-niveaux (hypothèse générale, hypothèses partielles, hypothèses adjacentes, hypothèses de modération).Sur le plan méthodologique, notre démarche se décline en deux phases qui reprennent les moments forts de notre travail de recherche. Une première phase exploratoire visant à explorer la PSE, à adapter et à reconfigurer notre modèle de recherche. Une deuxième phase déductive qui cherche à tester les hypothèses de la recherche et à établir les apports en termes de connaissances. L’investigation empirique conduite sur 132 entreprises tunisiennes issues de différents secteurs d’activité a permis d’entériner la systématicité de la PSE. En effet, la démarche sociétale de l’entreprise s’apparente à un processus contingent (fortement conditionné par les pressions institutionnelles), finalisé (produit des résultats en termes de performance), piloté (guidé par des principes et des convictions managériales), et soutenu (appuyé par des instruments et des mesures sociétaux). L’originalité de ce travail se justifie essentiellement par une logique multi-nivaux du modèle de recherche ainsi que par une démarche méthodologique adaptée à la complexité de l’objet de la recherche. De surcroît, cette problématique a été largement discutée dans le contexte occidental et essentiellement américain, elle reste encore peu explorée dans le monde Arabe et en particulier le Maghreb / The purpose of this research is to contribute to the study of Corporate Social Performance (CSP) concept, which provided theorizations remain highly controversial. Indeed, examination of the body of knowledge reveals theoretical, conceptual and empirical anomalies. These shortcomings relate on the operationalization of the CSP, the manner in which the concept has been linked to the notion of performance, and the lack of contextualization of PSE in relation to its institutional environment. It is therefore important to reorganize the concept within a framework that recognizes the dynamic and contingent character of CSP. Thus, this research aims to explore the concept of CSP and analyze its institutional dimension and its effects on organizational performance.On a theoretical level, the overall architecture of the thesis follows triple phase reasoning: deconstruction / reconstruction / validation. Deconstruction phase (first part) consists in highlighting theoretical, conceptual and empirical perspectives of the CSP. The reconstruction phase (second part) consists on developing a framework with systemic approach, which aims to unify different theoretical orientations. And finally, the validation phase (third party) consists on testing our conceptual framework. On the conceptual level, our framework mobilizes systemic approach. It declines institutional pressures as input to the system, PSE as a process, and organizational performance as a result of the system. The research model is articulated by multi-level hypotheses (general hypothesis, partial hypothesis, adjacent hypothesis and moderation hypothesis).On the methodological level, our approach is divided in two phases. An exploratory phase that aims to explore CSP, to adapt and to reconfigure our research model. A second phase seeks to test the research hypotheses and establish contributions in terms of knowledge.The empirical investigation conducted on 132 Tunisian companies endorses the systematicity of the CSP. In fact, the process of CSP is influenced by institutional pressures, piloted by the principles and managerial beliefs. Therefore, this process produces results in terms of performance, and it is supported by societal tools and measures.The originality of this work is essentially justified by multi-level research model as well as a methodological approach which is adapted to the complexity of the research object. In addition, this issue has been widely discussed in the American and European context, but it remains unexplored in the Arab world, particularly in the Maghreb

Os silos verticais são estruturas com elevado índice de deformações excessivas e ruptura causados, principalmente, pelo desconhecimento da variabilidade nas pressões devidas ao produto armazenado. O objetivo deste trabalho é apresentar um estudo teórico, numérico e experimental das pressões exercidas pelos produtos armazenados granulares nas paredes de silos esbeltos, com a proposta da incorporação de parâmetros com propriedades estocásticas, nos modelos de pressões apresentados na literatura. Os parâmetros mais relevantes dos modelos de pressões foram ajustados aos dados experimentais obtidos em um silo-piloto, utilizando a técnica de estimação de parâmetros por máxima verossimilhança (EMV), e, para isso, foram empregados os algoritmos genéticos (AGs) como procedimento de otimização. As avaliações experimentais no silo-piloto foram conduzidas com três produtos: soja, milho e ração. Com as variabilidades dos parâmetros dos modelos de pressões encontrados nos experimentos, a confiabilidade estrutural dos silos verticais metálicos cilíndricos de chapas onduladas e fundo plano foi avaliada por meio da técnica de simulação de Monte Carlo (SMC). Os resultados mostraram que os modelos de pressões de Janssen (1895) e de Jenike et al. (1973) podem ser utilizados para o cálculo das pressões com as variabilidades dos parâmetros representadas pela distribuição lognormal. A avaliação da probabilidade de falha para este sistema está acima dos limites recomendados internacionalmente, indicando que atenção especial deve ser dada aos projetos de silos verticais esbeltos. / Vertical silos are structures with a large number of deformations and failures mainly due to misunderstanding of pressure variability of the storage products. The aim of this work is theoretical, numerical and experimental study of wall pressure in slender silos with the incorporation of stochastic properties of the parameters in pressures models used in the international literature. The most relevant parameters of the pressure models were adjusted to the experimental data obtained from a pilot-silo using maximum likelihood function, and for this purpose, genetic algorithms (GA) were used in the optimization procedure. The experimental evaluation in pilot-silo was conducted with three different bulk solids, which are: maize, soy and animal feed mixture. With the pressures models parameters, the structural reliability of flat bottom corrugated cylindrical steel silos with was evaluated using Monte Carlo simulation (SMC) to simulate a stochastic process. The results showed that Janssen (1895) and Jenike et al. (1973) pressure models can be used to evaluate the pressures with the parameters uncertainties modeled to lognormal distributions. The reliability index determined in this structural system was less than international recommended values for the design of slender silos.

A maioria dos silos existentes no mundo não apresenta condições ideais de operação devido ao insuficiente conhecimento das pressões exercidas pelo produto armazenado principalmente na situação de descarga. A descarga excêntrica é comum em cooperativas e indústrias pois facilita o acesso na descarga do produto armazenado em trens e caminhões. Em contrapartida, nesta situação surgem pressões assimétricas que são a maior causa de acidentes e colapsos em silos. Até mesmo em silos concêntricos, as pressões assimétricas podem ocorrer. Ainda faltam muitas respostas com relação ao comportamento das pressões na descarga excêntrica, por isso, a maioria das normas internacionais recomenda a adoção de pressões adicionais para levar em conta os efeitos das pressões assimétricas, sendo que, estas recomendações variam muito de uma norma para outra e muitas vezes não são claras em suas afirmações. Este trabalho teve por objetivo principal o estudo teórico e numérico das pressões devidas ao produto armazenado em silos verticais com descarga excêntrica. Os resultados obtidos mostram que para a determinação das ações em silos esbeltos para o armazenamento de produtos de fluxo livre uma boa solução é a utilização dos métodos recomendados pelas normas EUROCODE e DIN, com algumas ressalvas: pressão no fundo do silo segundo a AS, estabelecimento de coeficiente de sobrepressão mínimo de 1,2 e porcentagem mínima de variabilidade das propriedades dos produtos, mesmo quando elas forem obtidas por meio de testes experimentais. / Most of the silos do not meet the ideal requirements for operation ought to many factors. One of the main factors is related to the lack of knowledge about the pressure imposed by the stored material, especially during discharge. In this work, the discharge done through eccentric silos is investigated, which is commonly employed by cooperatives and factories once they facilitate the access of trains and trucks to the discharged product. In those situations there is the occurrence of asymmetric pressure, which is the major cause of collapses and accidents in silos. There are still many pending answers regarding the pressure behavior in eccentric discharge; therefore, most international standards recommend the adoption of additional pressures in order to consider the effects of asymmetric pressures. The recommendations, however, are very diverse and not always clear. The results obtained show that, in order to determine the actions in slim silos for free flow product storage, it is important to use the methods recommended by the EUROCODE and DIN standards, with some exceptions: refer to the AS regarding to the pressure on the bottom of the silo, define the minimum underpressure coefficient as 1.2, and minimum percentage of product property variability, even if they are achieved through experimental tests.

A maioria dos silos existentes no mundo não apresenta condições ideais de operação devido ao insuficiente conhecimento das pressões, do fluxo e do grande número de variáveis que afetam o comportamento dos produtos armazenados. Isso explica também, a grande quantidade de acidentes e colapsos em silos. Uma análise dos principais códigos normativos indica a existência de divergências entre eles, principalmente quando se referem à determinação das pressões exercidas pelo produto armazenado sobre a estrutura, o mesmo ocorrendo entre as teorias propostas por pesquisadores. Este trabalho tem por finalidade apresentar um estudo teórico das pressões e fluxo em silos verticais esbeltos (h/d≥1,5) exercidas pelo produto armazenado. Para isso, um estado da arte das teorias de pressões e fluxo propostas pelos mais importantes pesquisadores e normas internacionais sobre o assunto foi desenvolvida. Como exemplo de aplicação, foram analisadas as pressões em um silo vertical esbelto com fundo cônico, para as situações de fluxo de massa e fluxo de funil, para dois produtos granulares. Com base nos resultados obtidos, foi elaborada uma proposta de norma brasileira para a determinação das pressões exercidas pelo produto armazenado para essas unidades, tendo em vista que o Brasil ainda não possui uma norma específica para o projeto e construção de silos. Além disso, foi desenvolvido um programa computacional de cálculo das pressões. / Silos are structures that usually present process and failures problems due to insufficient knowledge of bulk solids pressures and flow. An analysis of the principal international theories and standards shows divergences, mainly in the pressures determination due to the storage of bulk solids. This work presents a theoretical study of the pressures and flow in slender vertical silos (h/d≥1,5) due the storage of the bulk solids. An state of the art of the theories of pressures and flow proposed by the most important researchers and international standards on the subject is presented. As a practical example, the pressures were determined in a slender vertical silo with conical bottom, for mass and funnel flow patterns and for two granular materials. Based on the study, a proposal of Brazilian standard was elaborated for the determination of the pressures due the bulk solids for slender silos, considering that Brazil doesn't still have a specific standard for the design and construction of silos. A software for pressures determination was also developed.