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Lembrar é resistir: uma etnografia com a AUSSMPE – Associação de Usuários dos Serviços de Saúde Mental de Pelotas / Remember and resist:an ethnography with AUSSMPE – Associação de Usuários dos Serviços de Saúde Mental de PelotasDuarte, Rosi Marrero 30 August 2017 (has links)
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Previous issue date: 2017-08-30 / Sem bolsa / Este estudo apresenta a etnografia com a AUSSMPE – Associação de Usuários dos Serviços de Saúde Mental de Pelotas, a partir das experiências compartilhadas, sobretudo com base na produção imagética realizada junto a este coletivo. Tem como pano de fundo o questionamento sobre a permanência do modelo manicomial para internações psiquiátricas no município de Pelotas, apesar da reforma psiquiátrica e das novas diretrizes do Sistema Único de Saúde – SUS preconizarem o cuidado em saúde mental em liberdade. A partir dos desdobramentos junto a AUSSMPE, percebendo-os
enquanto coletivo de militância na luta antimanicomial, compreendemos as relações de força estabelecidas no campo e, por fim, contribuímos para a composição da memória da loucura neste território. Os desdobramentos apontaram dispositivos importantes no campo, sendo: a música, o desenho, a fotografia e o experimento vídeo/amador, habilidades em desenvolvimento pelos interlocutores, dadas como ferramentas para produção etnográfica. / This study presents the ethnography with the AUSSMPE - Associação de Usuários dos Serviços de Saúde Mental de Pelotas, based on the shared experiences, especially on the basis of the imagery produced together with this collective. Has as background the questioning about the permanence of the manicomial model for psychiatric hospitalizations in the Pelotas city, despite the psychiatric reform and the new guidelines of the Sistema Único de Saúde - SUS to advocate the mental health care in freedom. From the outspread of the AUSSMPE, perceiving them as a militant collective in the antimanicomial conflict, we understand the strenght relationships established in the field and, finally, we contribute to the composition of the memory of madness in this territory. The outspread showed important devices in the field, as: the music, the drawing, the photography and video/amateur experiment, skills about developed by the interlocutors, given as tools for ethnographic production.
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Estudo das propriedades estruturais e ópticas em materiais nanoestruturados a base de silício. / Study of structural and optical properties in nanostructured silicon based films.Márcia Ribeiro 11 May 2009 (has links)
Esta tese de doutorado tem por objetivo aprofundar as pesquisas realizadas no mestrado, a saber, da caracterização e estudo das propriedades estruturais e ópticas de filmes de oxinitreto de silício (SiOxNy:H) ricos em silício depositados pela técnica de deposição química a vapor assistida por plasma a baixa temperatura (PECVD). Os resultados obtidos no mestrado indicaram que os filmes de SiOxNy:H ricos em silício apresentam emissão luminescente na faixa do visível cuja intensidade e freqüência de emissão estão em correlação com o excesso de silício. Os resultados sugeriram que o excesso de silício na matriz do SiOxNy:H estava disposto na forma de aglomerados de silício de dimensões nanométricas responsáveis por efeitos de tamanho quântico bem como a estados radiativos na interface dos aglomerados com a matriz isolante. Neste trabalho a fim de avaliar o efeito da separação de fases, do tamanho quântico, e da interface, foram produzidos sistemas nanoestruturados a base de silício com total e parcial separação de fases para caracterizar e analisar suas propriedades ópticas e estruturais e compará-las com as dos filmes ricos em silício. Assim foram produzidas multicamadas de a-Si:H de poucos nanômetros de espessura com materiais dielétricos. Em algumas destas multicamadas foi promovida a mistura parcial das camadas por meio de bombardeamento iônico. O estudo nas estruturas de multicamadas permitiu caracterizar e analisar as propriedades estruturais e ópticas de materiais nanoestruturados com total e parcial separação de fases para posteriormente contrastá-los com as características dos filmes de oxinitreto de silício ricos em silício. A fim de analisar a influência da interface nas propriedades ópticas destes sistemas as multicamadas foram fabricadas com dois dielétricos diferentes: o óxido de silício e o ni treto de silício. A espessura das camadas dielétricas foi mantida fixa entanto que a das camadas de silício foi variada para avaliar efeitos de confinamento no silício. A caracterização foi feita utilizando técnicas de absorção óptica no UV-Vis, absorção no infravermelho (FTIR), espectroscopia Raman, fotoluminescência (PL), espectroscopia de absorção de raios X próximos 7 à borda do silício (XANES), e microscopia eletrônica de transmissão de alta resolução (HRTEM). Da análise dos resultados concluiu-se que o confinamento é fundamental para a existência da emissão luminescente embora o tipo de interface influencie a energia e a intensidade da emissão. A análise comparativa com as multicamadas permitiu verificar que os filmes de oxinitreto de silício ricos em silício apresentam, separação parcial de fases já como depositados, os tratamentos térmicos promovem a segregação do silício aumentando conseqüentemente a separação de fases. / The aim of this doctorate thesis is to enhance the knowledge in the research conducted along the Master degree based on the characterization and study of the structural and luminescent properties of silicon rich silicon oxynitride films (SiOxNy:H) deposited at low temperature by Plasma Enhanced Chemical Vapor Deposition (PECVD). The results of this study indicated that silicon rich SiOxNy:H films present luminescence in the visible spectra range with intensity and frequency in correlation with the silicon excess. The results suggested that the silicon excess in the SiOxNy:H matrix is confined in nanometric silicon clusters responsible for the to quantum size effects as well as for radiactive states at the interface of the silicon clusters with the insulating matrix. In the present work in order to evaluate the effect of phase separation, quantum size and interface effects si licon based nanostructured systems presenting total and partial phase separation were produced and their structural and optical properties were characterized in order to correlate them with the silicon rich films ones. In this way multilayers with few nanometers thick a-Si layers with dielectric materials were produced. The mixture of the layers was promoted by ion bombardment in some of these multilayers. The study of these structures permitted the characterization of structural and optical properties of materials with total and partial phase separation with the purpose of comparing them to the silicon-rich silicon oxynitride films characteristics. In order to analyze the interface influence in the optical properties, multilayers systems with two different dielectric materials, silicon oxide and silicon nitride, were fabricated. The dielectric layer thickness was kept constant while the silicon layer was varied in order to study the confinement effect. The characterization was done utilizing UV-Vis optical absorption, infrared absorption (FTIR), Raman spectroscopy, Photoluminescence (PL), X-ray absorption near edge spectroscopy (XANES) and high-resolution transmission electron microscopy (HRTEM) techniques. From the results analysis it was concluded that confinement is essent ial for the existence of luminescent 9 emission although the type of interface also influences the energy and intensity of the emission. The comparative analysis with the multilayers permitted to verify that the silicon-rich silicon oxynitride films present, as deposited, partial phase separation and that the thermal treatments promotes silicon aggregation thus increasing the phase separation.
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Análises de campo e laboratório do comportamento ao longo do tempo de muros de solos tropicais finos reforçados com geossintéticos. / Field and laboratory analysis of time dependent behavior of geosynthetic reinforced soil walls with fine soil.Rafael Ribeiro Plácido 17 November 2016 (has links)
Este trabalho apresenta um estudo sobre o comportamento ao longo do tempo de estruturas em solos finos reforçados com geossintéticos. O programa de atividades desenvolvido para este fim compreendeu três etapas: leituras de deformações de uma estrutura real de solo reforçado com geossintéticos, ensaios de laboratório de fluência confinada e isolada e modelagens computacionais da obra de referência. A estrutura real foi monitorada em duas seções distintas, sendo uma delas construída em geotêxteis não tecidos e a outra em geotêxteis tecidos. As leituras de deformação foram realizadas por um período de quatro anos. As condições da obra real foram utilizadas como referência para o planejamento dos ensaios de fluência em isolamento e confinamento. Os ensaios confinados foram conduzidos inicialmente no equipamento de fluência confinada desenvolvido por Costa (2004), no qual o carregamento é imposto de forma indireta ao reforço. Os ensaios foram realizados empregando o mesmo solo de aterro da obra real, com diferentes níveis de carregamento vertical (140, 200, 300 e 400 kPa) e com diferentes umidades de compactação (8%, 11,7% e 16%). Os ensaios com carregamento de 140 kPa foram repetidos no equipamento de fluência confinada-acelerada desenvolvido por França (2011), permitindo uma comparação teórica e prática entre os dois equipamento utilizados. Ensaios adicionais foram realizados para avaliar o comportamento ao longo do tempo de geossintéticos confinados submetidos a um processo de inundação do solo. E para finalizar a campanha de ensaios foram realizados testes para a verificação do incremento de cargas nos reforços devido aos efeitos da compactação do maciço. As modelagens computacionais foram realizadas empregando o software Plaxis 2D. A partir dos modelos numéricos foi possível verificar os mecanismos desenvolvidos ao longo do tempo de estruturas de solos reforçados com geossintéticos. A modelagem numérica permitiu extrapolar o comportamento da estrutura para outro tipo de reforço (geogrelha) e para tempos bem mais elevados do que os tempos reais de leitura. As previsões de comportamento foram realizadas para tempos de até 100 anos. Os resultados da campanha de ensaios mostraram que os reforços confinados em solo estão sujeitos aos fenômenos da fluência e da relaxação ao longo do tempo. Os resultados mostraram que as taxas de fluência e de relaxação foram mais elevadas para os maiores carregamentos verticais. Os ensaios adicionais mostraram que os reforços sofreram um incremento significativo de carga devido aos efeitos da compactação e que a rigidez confinada dos reforços praticamente não se alterou devido aos efeitos da inundação. A previsão do comportamento do muro de referência utilizando o MEF mostrou que a estrutura deve apresentar baixos níveis de deformação para períodos de até 100 anos. A análise conjunta de todos os resultados obtidos ao longo do trabalho permitiu o desenvolvimento de um modelo analítico que permite a previsão do comportamento de muros reforçados com geossintéticos a partir de resultados de ensaios de fluência em isolamento. A aplicação do modelo proposto para o caso do muro real mostrou uma boa coerência entre os resultados previstos e os resultados medidos em campo. / This dissertation presents a study on time-dependent behavior of geosynthetic reinforced soil walls with fine soil. The testing program comprised of three distinct steps: field assessment of an instrumented geotextile reinforced soil wall, in-air and in-soil laboratory creep tests, and numerical analysis of the instrumented wall. Reinforcement strains were monitored in two different cross-sections: one built with nonwoven geotextile and the other built with woven geotextile. The strains were monitored during four years of service. The field conditions were used as the basis for planning in-air and in-soil creep tests. The in-soil creep tests were initially conducted using the confined-creep test apparatus developed by Costa (2004), which simulates the typical load transfer mechanism in reinforced soil structures. The in-soil tests were performed using the same soil used in the instrumented wall. These tests were carried out at different levels of vertical load (140, 200, 300 and 400 kPa) at the optimum water content (11.7%) and at different compaction water content of the soil (8%, 11.7% and 16%) at 140 kPa. The tests with 140 kPa of vertical load were replicated using the confined-accelerated creep test apparatus developed by França (2011). These tests allowed a theoretical and practical comparison between the two different in-soil creep testing apparatuses utilized in the testing program. Additional in-soil creep tests were conducted to evaluate the behavior of confined geosynthetics with time submitted to flooding of the top soil layer above the reinforcement. Compaction tests were also performed to check the increase of reinforcement loads due to soil compaction. Numerical modelling was carried out with the Finite Element Method (FEM) using Plaxis 2D. The numerical models allowed evaluation of the geotechnical mechanisms developed with time on geosynthetic reinforced soil wall structures. These models were also used to predict timedependent strains for longer periods (until 100 years) and for different types of reinforcements. The results of the testing program showed that the reinforcements confined in soil presented creep and stress relaxation behavior with time. The results also showed that the creep and relaxation rates were higher for larger vertical loads. It was observed that the confined stiffness of the reinforcement was virtually the same regardless the occurrence of flooding in the top soil layer. Additionally, the compaction tests showed that the larger the difference of the soil compaction water content from the optimum, the larger the loads in the reinforcement. Behavior prediction of the monitored, full-scale wall using FEM showed that the structure should have low strain levels for periods up to 100 years. The laboratory test results and the mechanisms learned from the FEM analysis allowed the development of an analytical model for predicting geosynthetic-reinforced soil wall behavior from results of in-air creep tests. The strain results of the analytical model applied to the monitored full-scale wall showed that the predicted strains are in good agreement with the field strains.
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O loop de Wilson em quarta ordem / The Wilson loop in the fourth orderRubens de Melo Marinho Junior 25 April 1984 (has links)
o loop de Wilson se apresenta como uma variável muito apropriada para servir de base para uma teoria das forças nucleares. Esta afirmação é justificada se lembrarmos que a apresentação usual da cromodinâmica quântica perturbativa parte de variáveis coloridas, um fato altamente criticável, pois elas não representam qualquer variável física, enquanto que na eletrodinâmica as variáveis que descrevem os elétrons e fótons são físicas. Esta possibilidade de estudar as interações entendimento da fortes implica na necessidade de um claro estrutura analítica dos loops de Wilson. O objetivo deste trabalho e usar a técnica da regularização dimensional para discutir a estrutura dos diagramas da expansão perturbativa do loop de Wilson em quarta ordem. A introdução do número de dimensões como variável analítica, isola as divergências sob a forma de polos no plano complexo da dimensão, facilita a discussão da renormalização, além de proporcionar um método invariante de gauge. Com esta técnica renormalizamos a constante de acoplamento das interações fortes até a quarta ordem e mostramos que em quatro dimensões 0 resíduo não depende nem da curva nem do área no qual ele e calculado. Também mostramos que é possível calcular a parte finita do loop de Wilson para 0 caso especial de duas semi-retas de mesma origem. / The Wilson loop shows itself as a very appropriate variable to be used as a base in a theory of nuclear forces. This statment is justified if we remember that the usual presentation of perturbative quantum chromodynamics starts from colored variables, a fact itself subject to critism since they do not represent any physical variable, whereas in the usual quantum eletrodynamics the variables that describes eletrons and photons are physical. This possibility of studying strong interactions implies the need of clear a understanding of the analytical structure of the Wilson loops. The purpose of this dissertation is to use the technique of dimensional regularization to discuss the structure of perturbative expansion diagrams of the Wilson loops up to fourth order. The introduction of the number of dimensions as an analytical variable isolates the divergences in the form of poles in the complex plane of the dimensions, make the renormalization procedure easier and also makes the method gauge invariant. With these techniques we have renormalized the coupling constant of strong interactions up to fourth order and have also show that in four dimension the residue is dependent neither on the curve nor on the arc on which it is calculated. We have also shown that it is possible to calculate the finit part of the Wilson loops for the special. Case of two half lines with the same origin.
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Efeito da dieta com e sem volumoso para ovinos em terminação / Efecto de la dieta con y sin voluminosos para el acabado de las ovejas / Effect of diet with and without bulking for finishing sheepMENDES, Jéssica Antonia Cardoso 21 February 2017 (has links)
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Previous issue date: 2017-02-21 / The objective of this study was to evaluate the effect of the use of a non-voluminous diet on
feeding confined sheep on nutrient intake, water intake, performance, nutrient digestibility,
ingestive behavior and feed cost analysis. Sixteen male, castrated, mixed Dorper x Santa Inês
mongrels were distributed in two treatments with eight replicates and eight complete
randomized blocks, according to the initial weight (23,68 ± 4,21 kg). The sheep were placed
in individual pens for a period of 65 days, 18 days for the adaptation of the animals to the
experimental diets and 44 days for data collection. After the period of confinement, the
animals remained for another 3 days in the bays, for the digestibility assay, through total
collection of feces. The treatments consisted of a diet with voluminous (with voluminous
ratio: concentrate, 30:70) and no voluminous diet (pelleted ration). The dry weight diet,
organic matter, crude protein, ethereal extract, neutral detergent fiber, acid detergent fiber,
total carbohydrates, non-fibrous carbohydrate, metabolizable energy were reduced (P<0,05);
And provided lower average daily weight gain (120,64 g), as well as increased feed
conversion (6,82) and water intake per kg of dry matter (3,70 kg/kg MS day) of sheep
finished in Confinement. This diet increased (P<0,05) the digestibility of neutral detergent
fiber (NDF) and acid detergent fiber (FAD) by 6,7% in relation to the diet with roughage. The
lambs fed the non-bulking diet presented the lowest averages (P<0,05) spent with the
activities: feeding time (0,84 h/day), feeding frequency (5,50), rumination time (1,22 h/day)
and total chewing time (2,53 h/day). The feed time (21,46 h/day), MS ingestion efficiency
(1159,02 g MS/ h) and NDF (371,81 g MS/ h), DM rumination efficiency (497,76 g MS/ h)
and NDF (158,36 g MS/ h) of the animals fed the no-bulking diet was higher (P<0,05) than
the bulky diet. The non-voluminous diet provided a negative profit margin (-13,17 R$/
animal). Therefore, lambs fed the non-bulking diet had lower bieconomic performance. / Este estudio tuvo como objetivo evaluar el efecto de la dieta sin uso masivo en la alimentación de las ovejas
corral de engorde en la ingesta de nutrientes, la ingesta de agua, el rendimiento,
digestibilidad de los nutrientes, el comportamiento y análisis de costos con el poder de la alimentación.
Dieciséis ovejas macho castrado cruza Dorper x Santa Inés se dividieron en dos
tratamientos con ocho repeticiones y ocho bloques completos al azar, como el peso inicial
(23.68 ± 4.21 kg). Las ovejas se colocaron en corrales individuales durante un periodo de 65
días, 18 días para los animales para adaptarse a las dietas y 44 para recoger
datos. Después del período de alimentación, los animales se mantuvieron durante 3 días en las bahías,
para el ensayo de digestibilidad, a través de la colección total de heces. los tratamientos
en una dieta de forraje (con forraje: concentrado de relación, 30:70) y dieta libre
Bulky (alimentación de pellets). La dieta sin (P <0,05) consumos reducidos voluminosos: de
materia seca, materia orgánica, proteína cruda, extracto etéreo, fibra detergente neutro, fibra
detergente ácido, hidratos de carbono totales, no fibroso de hidratos de carbono de energía metabolizable; y
dio menor ganancia media diaria de peso (120,64 g), y la conversión aumentado
alimentación (6,82) y la toma de agua por kg de materia seca (3,70 kg / kg día DM) ovejas
feedlot terminado. Esta dieta aumentó (P <0,05) en la digestibilidad de la fibra
fibra detergente neutro (NDF) y fibra ácido detergente (ADF) en 6,7% en comparación con la dieta
voluminosos. Los corderos alimentados con la dieta sin fibra tuvieron la más baja
medios (P <0,05) gastado en actividades: tiempo de alimentación (0,84 h / día)
velocidad de alimentación (5.50), el tiempo de rumia (1,22 horas / día) y el tiempo total de mascar (2,53
h / día). El tiempo de inactividad (21,46 m / día), la eficiencia de consumo de MS (1159,02 g DM / h) y
NDF (371,81 g DM / h), la eficiencia rumia MS (497,76 g DM / h) y NDF (158,36 g
MS / h) de los animales alimentados con la dieta sin voluminoso fue mayor (P <0,05) en comparación con
dieta con fibra. Una dieta sin fibra proporciona el margen de beneficio negativo (- 13,17
R $ / animal). Por lo tanto, los corderos alimentados con la dieta sin fibra presentan
bieconômico menor rendimiento. / Objetivou-se avaliar o efeito da utilização de dieta sem volumoso na alimentação de ovinos
terminados em confinamento sobre o consumo de nutrientes, ingestão de água, desempenho,
digestibilidade de nutrientes, comportamento ingestivo e análise de custo com a alimentação.
Dezesseis ovinos machos, castrados, mestiços Dorper x Santa Inês foram distribuídos em dois
tratamentos com oito repetições e oito blocos completos casualizados, conforme o peso inicial
(23,68 ± 4,21 kg). Os ovinos foram colocados em baias individuais por um período de 65
dias, sendo 18 dias para a adaptação dos animais às dietas experimentais e 44 para a coleta de
dados. Após o período de confinamento, os animais permaneceram por mais 3 dias nas baias,
para o ensaio de digestibilidade, por meio de coleta total de fezes. Os tratamentos consistiram
em uma dieta com volumoso (com relação volumoso: concentrado, 30:70) e dieta sem
volumoso (ração peletizada). A dieta sem volumoso reduziu (P<0,05) os consumos: de
matéria seca, matéria orgânica, proteína bruta, extrato etéreo, fibra em detergente neutro, fibra
em detergente ácido, carboidratos totais, carboidrato não fibroso, energia metabolizável; e
proporcionou menor ganho de peso médio diário (120,64 g), bem como aumentou a conversão
alimentar (6,82) e a ingestão de água por kg de matéria seca (3,70 kg/kg MS dia) de ovinos
terminados em confinamento. Esta dieta aumentou (P<0,05) a digestibilidade da fibra em
detergente neutro (FDN) e fibra em detergente ácido (FDA) em 6,7% em relação a dieta com
volumoso. Os cordeiros alimentados com a dieta sem volumoso apresentaram as menores
médias (P<0,05) despendidas com as atividades: tempo de alimentação (0,84 h/dia),
frequência alimentar (5,50), tempo ruminação (1,22 h/dia) e tempo de mastigação total (2,53
h/dia). O tempo de ócio (21,46 h/dia), eficiência de ingestão de MS (1159,02 g MS/h) e da
FDN (371,81 g MS/h), eficiência de ruminação da MS (497,76 g MS/h) e da FDN (158,36 g
MS/h) dos animais alimentados com a dieta sem volumoso foi maior (P<0,05) em relação à
dieta com volumoso. A dieta sem volumoso proporcionou margem de lucro negativa (- 13,17
R$/animal). Sendo assim, os cordeiros alimentados com a dieta sem volumoso apresentaram
menor desempenho bieconômico.
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Force de résistance au mouvement d'un objet dans un milieu granulaire / Resistance force on an object moving into a granular mediaMartinez Carreaux, Francisco Javier 18 December 2013 (has links)
Cette thèse porte sur la force de résistance au mouvement à faible vitesse d'un objet (sphère, cylindre ou disque) dans un empilement de grains dense et sec. Des expériences ont été menées sur deux dispositifs permettant un mouvement à vitesse contrôlée, en s’intéressant à l’influence des tailles des objets et des grains, des conditions aux limites de l’empilement, de la gravité, et d’une éventuelle vibration de l’empilement. Dans un premier dispositif expérimental permettant un mouvement vertical, nous avons consacré une partie importante de ce travail à l'étude de la forte asymétrie de la force lors de cycles de pénétration/extraction d’un cylindre horizontal et d’une sphère. Pour tenter de comprendre l'origine de cette asymétrie, différentes conditions aux limites ont été considérées : parois rigides ou souples sur les côtés ou au fond de l’empilement, surface libre ou surmontée d’un couvercle plus ou moins chargé en haut de l’empilement. La longueur caractéristique issue du champ de vitesse des grains autour d'un cylindre a été montrée comme la longueur pertinente à considérer pour le confinement latéral, ainsi que pour les déformations de la surface libre telles que la formation d’un cratère consécutif à la pénétration ou d’une bosse lors de l’extraction. Ces déformations peuvent être retrouvées par intégration d’un modèle de champ de vitesse autour de l’objet. La présence d'un couvercle chargé a par ailleurs permis de mettre en évidence une riche et complexe variété de comportements, notamment en extraction où la force ne diminue plus avec la profondeur de l’objet. Dans un second dispositif permettant le mouvement horizontal d’un gros disque intrus à l’intérieur d’une couche de petits disques photoélastiques vibrés ou non, nous avons mesuré la force globale sur l’intrus et visualisé les distributions de contraintes au sein du milieu granulaire. Au-delà des importantes fluctuations spatio-temporelles, des valeurs moyennes de force sur l’intrus et des tenseurs locaux de contraintes et taux de déformations autour de l’intrus ont pu être obtenus, dans la perspective d’établir une loi de comportement locale pour le milieu. La vibration de la couche de grains a été montré pouvoir changer considérablement la dépendance de la force avec la vitesse de l’intrus, avec un effet de fluidification du milieu. / This thesis focuses on the force of resistance to the slow motion of an object (sphere, cylinder or disk) in a dense and dry granular medium. Experiments were conducted using two devices that permitted movement at constant velocity, with the aim of studying the influence of the object size, the grain size, the boundary conditions, and vibration of the grains. Using the first device in which the object moved vertically, we studied in detail the strong asymmetry of the resistance force during cycles of penetration/withdrawal of a horizontal cylinder and a sphere. In an attempt to understand the origin of this asymmetry, we implemented different boundary conditions: rigid and deformable walls on the sides and/or the bottom of the device, and free and quasi-rigid (loaded cover) conditions at the top. Previous work has shown that the characteristic length scale of the velocity field around a moving cylinder is the relevant length for both the lateral confinement and the deformation of the free surface, such as the formation of a crater during penetration or a mound during withdrawal. These deformation fields can be found by integrating a model of the velocity field around the object. Our use of a loaded-cover boundary condition has also revealed a variety of complex behaviors, including a force that no longer decreases with the depth of the object during the withdrawal phase. The second device allows the horizontal movement of a large hard intruder into a monolayer of small photoelastic disks which could be vibrated or not. Using this, we measured the overall force on the intruder and visualized the stress distribution in the granular medium. We were able to measure not only the large spatio-temporal velocity fluctuations, but also average values of the force on the intruder and the local stress and strain rate tensors around it, which allowed us to determine a local constitutive law for the medium. Finally, we have shown that vibration of the grains significantly changes the dependence of the force on the intruder speed, indicating a fluidization effect.
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The Influence of Information on Public Support for Solitary Confinement: a Test of Belief Updating and Confirmation BiasLaBranche, Kayla J. 31 May 2018 (has links)
There is limited research measuring public opinion about the correctional practice of solitary confinement (SC). Given that public opinion can influence policies, it is important to determine whether or not one's beliefs can be updated upon receiving information about the use and effect of SC. Prior research indicates that public opinion is malleable, and thus, may be susceptible to modification. Though, people may be more willing to update their beliefs when the information they receive confirms their existing beliefs (i.e., confirmation bias). This study used an experimental design in which participants were asked to provide their opinions on a series of statements designed to measure their support for SC. Participants were randomly assigned to one of two treatment conditions that provided differing messages about the use of SC through brief, informational videos. Participants were either told that SC is a necessary tool to maintain order within prisons, or that SC is harmful to those who experience it. Following the intervention, participants' support for SC was re-measured and their change in score was calculated. Analyses indicated that participants who received information stating that SC is harmful decreased their support for the practice, while those who received information stating it was necessary increased their support for its use. To test for confirmation bias, participants were presented a survey instrument designed to measure their existing support for punishment. The findings indicate that participants had greater belief changes when presented with disconfirming information. These effects were more pronounced when examining moderating demographic variables. The research and policy implications of this study's findings are discussed.
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Effect of heater type on CO/CO2 concentrations in a farrowing barnYang, Anthony Yuan-Jung 01 July 2015 (has links)
Clear evidence shows a relationship between working in swine facilities and developing respiratory illnesses. Health effects have been associated with exposures to the combination of dust, ammonia, and carbon dioxide (CO2). This study examined whether room concentrations of combustion gases could be improved by changing the in-room vented heaters common to animal production operations to heaters that vent combustion gases outside.
Concentrations of CO2 and carbon monoxide (CO) were monitored during two winter seasons, with the 2013-14 season using the traditional gas-fired heater (Guardian 60, L.B.White Co.) and the 2014-15 winter using new vented heaters (Effinity93, Modine Manufacturing Co.) Direct-reading CO (VRAE, Rae Systems) and CO2 (ToxieRAE Pro, Rae Systems) monitors were deployed at fixed stations throughout the farrowing barn to measure gas concentrations. Differences in mean gas concentrations between heater types, as well as the relationship between CO2 and temperature, sow, and piglet count, were evaluated using linear regression.
Carbon dioxide concentrations exceeded industry recommended limits (1540 ppm) on all sample days (N=18) with the standard in-room vented heaters in operation: concentrations averaged half of the TLV (2500 ppm). With the new vented heaters, 24-hour averaged CO2 concentrations exceeded industry recommended limits on only three out of 20 sample days: concentrations averaged 1400 ppm. The new heater significantly reduced CO2 by 44% and CO by 60% from 2.0 to 0.8 ppm (p2=0.75) between CO2 and production factors (temperature, sow and piglet count) for the new heater: CO2 (ppm) = 482 - 22.4(Temp °C) + 43(# sow) + 5.6(# piglet). Similar analysis for the old heater identified similar trends but substantially different intercept (1700 ppm) and temperature factor (-36.9).
While CO2 is still generated from swine respiration, we found significant reductions in room concentrations with the simple replacement of commonly used equipment. Future work will include an assessment of the longevity of these heaters in the swine barn environment
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Women's Narratives of Confinement: Domestic Chores as Threads of Resistance and HealingSmith, Jacqueline Marie 13 March 2015 (has links)
The term "narratives of confinement" redefines the parameters by which first-person, fictive and non-fictive, accounts of female captivity are classified, broadening the genre beyond Indian captivity narratives and slave narratives to include other works in which female narrators describe physical and/or psychological confinement due to tangible or non-tangible forces. Often these narratives exhibit the transformation of the drudgery of housewifery into powerful symbols of resistance and subversion, especially in reaction to traumatic events related to confinement. Needlework and food, including its preparation and distribution, frequently emerge as metaphors that express the ways in which disempowered women seek to regain control in their lives: sewing often represents an effort by women to seize power, blending the creative act with economic achievement; food preparation also relates to creativity and economic achievement and often represents love and nurturing. In this study, I examine three representative narratives of confinement, using close reading and scholarly evidence as support: Mary Rowlandson's 1682 Indian captivity narrative, A True History of the Captivity and Restoration of Mrs. Mary Rowlandson; Harriet Jacobs' 1861 slave narrative, Incidents in the Life of a Slave Girl: Written by Herself; and Toni Morrison's 1987 fictional neo-slave narrative, Beloved. My examination begins the dialogue regarding the connection between domestic metaphors and narratives of confinement, broadening scholarship to allow more consideration for the subtle, feminized language of domesticity.
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Active Cellular Nematics / Nématiques cellulaires actifsDuclos, Guillaume 15 December 2015 (has links)
Des cellules allongées et apolaires cultivées à confluence s'alignent les unes avec les autres. Dans cette thèse, nous utilisons des concepts de la théorie de la matière active ainsi que de la physique des cristaux liquides afin d'étudier quantitativement l'émergence de cet ordre mésoscopique nématique pour des monocouches de cellules à deux dimension, avec et sans confinement. Il a été montré que les défauts topologiques jouent un rôle crucial durant l'auto-organisation de systèmes biologiques actifs. Ici, nous étudions la dynamique de ces défauts qui se forment dans le tissu nématique contractile. Étant intrinsèquement hors équilibre à cause de la consommation d'énergie par les cellules, la monocouche est parcourue par de complexes courants de cellules due à la migration spontanée des défauts et leur annihilation avec des défauts de charges opposées. En comparant nos résultats expérimentaux avec un modèle théorique, nous montrons que l'auto-organisation de la monocouche est liée à la minimisation de l'énergie de courbure du tissu. / Elongated, weakly interacting, apolar cells cultured at confluence align together, forming large domains where they are perfectly ordered. Using concepts from the active matter theory and the physics of liquid crystals, we study the emergence of this mesoscopic nematic order by quantifying the ordering dynamics in two-dimensional infinite monolayers or under confinement. Topological defects have been found to play a crucial role in the self-organization of active biological systems. We study the dynamics of the disclinations that form in these cellular contractile nematics. Being driven out of equilibrium by the consumption of energy by individual cells, the monolayer exhibits complex flow patterns as defects migrate spontaneously and annihilate pairwise. By comparing our experimental results to a nematic drop model, we show that the self-organization of the cellular nematic layer with no boundary conditions or under circular confinement is dictated by the minimization of the splay and bend distortions of the tissue.
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