Thesis (Master of Civil Engineering) University of California, Berkeley, December 1996. / "December 1996." Includes bibliographical references (l. 76-79). Also available online.

Submitted by Claudinei Pracidelli (cpracide@ipen.br) on 2016-11-11T12:57:29Z No. of bitstreams: 0 / Made available in DSpace on 2016-11-11T12:57:29Z (GMT). No. of bitstreams: 0 / Neste trabalho buscou-se conhecer as perspectivas de sustentabilidade socioambiental no contexto do desenvolvimento do turismo na cidade de Mateiros/Tocantins. Para tanto, foi avaliada a aplicabilidade em destino de pequeno porte dos indicadores de sustentabilidade: Índice de Qualidade de Vida (IQV), Indicadores de Sustentabilidade da Organização das Nações Unidas (ONU) e Pegada Ecológica do Turismo. Percebeu-se que houve um incremento no IQV da cidade de Mateiros de 32,82% após o estabelecimento do turismo, com destaque para as famílias que atuam na produção das peças de artesanato de capim dourado. A mudança, de 0,162 para 0,215, indica que apesar de ter havido uma elevação na qualidade de vida das famílias entrevistadas, o IQV permaneceu baixo, isto é, com valores entre zero e 0,499. Tal fato demonstra que a qualidade de vida das famílias não é satisfatória. Quanto à ferramenta da ONU, percebeu-se que não há sistematização de dados suficientes para que esta ferramenta possa ser utilizada pelos órgãos governamentais na captação de recursos e utilização destes para criar novas políticas públicas para a região. Tal fato demonstra uma ineficácia em destinos de pequeno porte que se assemelhem à cidade de Mateiros na forma em que foi utilizado nesse trabalho. Quanto à Pegada Ecológica do Turismo, de acordo com a metodologia proposta, são necessários 2.194,2263 hectares de terras para absorver o CO2 demandado pela atividade turística na região. A categoria com maior impacto foi terras de energia fóssil na subcategoria transporte terrestre. Conclui-se, então, que os indicadores de sustentabilidade Pegada Ecológica do Turismo e Índice de Qualidade de Vida mostraram-se ferramentas eficazes para se avaliar as perspectivas de sustentabilidade de destinos de pequeno porte. / Tese (Doutorado em Tecnologia Nuclear) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP

Este estudo teve como objetivos: compreender como se dá o processo de o enfermeiro exercer sua autonomia nas decisões de final de vida vivenciadas em UTI adulto; identificar os significados que ele atribui à experiência de tomar decisões e de exercer sua autonomia nas situações de final de vida dos pacientes internados na UTI adulto; construir uma teoria substantiva sobre a compreensão de exercer a sua autonomia nas tomadas de decisão em situações de final de vida dos pacientes na UTI adulto. Utilizou-se como referencial teórico o Interacionismo Simbólico e como referencial metodológico a Teoria Fundamentada em Dados. A análise comparativa dos dados possibilitou desvendar o significado de exercer autonomia do enfermeiro com pacientes em final de vida internados na UTI adulto. Foi possível serem identificados três fenômenos que compõem esta experiência. O primeiro,Trabalhando num ambiente de pressão, representa a etapa inicial da experiência do enfermeiro, agrega não somente o contexto que permeia o seu trabalho na UTI, mas também os aspectos clínicos do paciente, as interações com os outros profissionais e com a família nas tomadas de decisão de final de vida. O segundo,Buscando empoderar-se para poder decidir, mostra o movimento, no qual o enfermeiro cria estratégias para ampliar as oportunidades a fim de poder exercer autonomia. O terceiro,Revendo os espaços para exercer autonomia, reconsidera outros espaços onde possa atuar no processo de final de vida, em relação ao planejamento do cuidado ao paciente, no acolhimento das famílias nas tomadas de decisão ou, ainda, na interface com os membros da equipe e a instituição. A articulação destes fenômenos permitiu identificar a categoria central AMPLIANDO AS OPORTUNIDADES PARA EXERCER A AUTONOMIA, que representa o processo vivido pelo enfermeiro na busca de espaços de poder de decisão e de ação ao assumir seu papel nos cuidados no processo de final de vida. / The purpose of this study is to: understand the process of autonomy exercised by nurses when making decisions related to end-of-life situations they in the adult ICU; to identify the meanings that nurses attribute to the experience of making decisions and of exercising their autonomy in end-of-life situations of adult patients in ICU; to construct a theoretical model about the process of understanding the exercise of their autonomy in decision-making relating to end-of-life situations of adult patients in the ICU. The study used as a theoretical reference the Symbolic Interactionism, and as methodological reference, the Grounded theory. The comparative analysis of the data has permitted the understanding of the meaning of nurses experience in exercising autonomy relating to life-ending adult patients in the ICU. Three phenomena that compose this experience have been identified: The first, \"Working in an environment of pressure,\" represents the initial phase of nurses experience, adding not only the features that exist within the ICU where the work is done, but also the clinical aspects of patients interaction with other professionals and family in end of life decision-making. The second, \"Seeking to gain power in order to be allowed to make decisions,\" shows the movement in which nurses create strategies for expanding opportunities in order to exercise autonomy. The third phenomena, \"Reviewing the spaces to exercise autonomy,\" reconsiders other spaces where nurses can act in end-of-life situations regarding planning of patient care, supporting families on their decision making and interface with health team members and the institution. The articulation of these phenomena has permitted the identification of the central category EXPANDING-THE-OPPORTUNITIES-FOR-EXERCISE AUTONOMY, based on which it has been possible to propose a theoretical model that explains the experience. It represents the process experienced by nurses in seeking spaces of power regarding decision making and action to assume the care role in end-of-life process.

In recent years international space agencies have become more and more explicit about long term lunar and Martian space missions. With the space program Terrae Novae, the European Space Agency puts forward a focus on the development of Human & Robotic Exploration technologies essential in enabling such long term missions. An integral component of this program is the focus on Advanced Life Support Systems. Life support systems are operated to provide astronauts with life necessities like oxygen, water and food. Currently, conventional Life Support System often have a linear supply design, relying on resources shipped from Earth, with limited onboard re-usage. However, for extended space missions, this linear supply model becomes impractical due to the constraints of dry mass during space travel. Given this need, the European Space Agency initiated the MELiSSA (Micro-Ecological Life Support System Alternative) project aimed at the development of a bioregenerative life support systems. In previous works, the MELiSSA Loop has been proposed: a system design inspired by terrestial ecosystems, that consists of multiple compartments that perform specific biological functions like nitrification and biosynthesis. Due to the complex interdependence of the individual compartments and general space system requirements, the control of such this cyber-physical system forms a significant challenge. This thesis proposes a previously undescribed architecture for the MELiSSA Loop controller design that coordinates the resource distribution between the compartments and establishes atmosphere revitalisation. The architecture meets control objectives specified at high level, and at the same time satisfies the physical and operational constraints. / Under de senaste åren har internationella rymdorganisationer blivit mer och mer tydliga om långsiktiga mån- och rymduppdrag på mars. Med rymdprogrammet Terrae Novae lägger Europeiska rymdorganisationen fram ett fokus på utvecklingen av Human & Robotic Exploration-teknik som är nödvändig för att möjliggöra sådana långsiktiga uppdrag. En integrerad del av detta program är fokus på Advanced Life Support Systems. Livsuppehållande system används för att förse astronauter med livsnödvändigheter som syre, vatten och mat. För närvarande har konventionella livsuppehållande system ofta en linjär försörjningsdesign som förlitar sig på resurser som skickas från jorden, med begränsad återanvändning ombord. Men för utökade rymduppdrag blir denna linjära försörjningsmodell opraktisk på grund av begränsningarna av torr massa under rymdresor. Med tanke på detta behov initierade Europeiska rymdorganisationen MELiSSA-projektet (MicroEcological Life Support System Alternative) som syftade till att utveckla ett bioregenerativt livsuppehållande system. I tidigare arbeten har MELiSSA Loop föreslagits: en systemdesign inspirerad av terrestiska ekosystem, som består av flera fack som utför specifika biologiska funktioner som nitrifikation och biosyntes. På grund av det komplexa ömsesidiga beroendet mellan de enskilda avdelningarna och allmänna krav på rymdsystem, utgör kontrollen av sådana detta cyberfysiska system en betydande utmaning. Denna avhandling föreslår en tidigare obeskriven arkitektur för MELiSSA Loopkontrollerdesignen som koordinerar resursfördelningen mellan avdelningarna och etablerar återupplivning av atmosfären. Arkitekturen uppfyller styrmål som anges på hög nivå, och uppfyller samtidigt de fysiska och operativa begränsningarna.

Submitted by Claudinei Pracidelli (cpracide@ipen.br) on 2016-11-11T13:30:20Z No. of bitstreams: 0 / Made available in DSpace on 2016-11-11T13:30:20Z (GMT). No. of bitstreams: 0 / Desde que foi reconhecida a importância de se planejar um turismo sustentável, tem-se buscado ferramentas adequadas para monitorá-lo nas destinações turísticas, tornando esse um dos principais desafios da academia científica de estudos do turismo na atualidade. Diante desse contexto, o desafio apresenta-se ainda maior, quando tratamos de turismo em unidades de conservação, tendo em vista que envolve um ambiente altamente sensível e comunidades em seu entorno que podem ter, no desenvolvimento dessa atividade, sua principal renda econômica. Assim, o que se propõe neste estudo é analisar a aplicabilidade e a eficiência metodológica do monitoramento que visa ao auxílio na construção da sustentabilidade do turismo, em unidades de conservação, através de um estudo de caso no Parque Estadual do Jalapão, localizado no Estado do Tocantins, Brasil. Prioriza-se a investigação de indicadores locais abordados a partir da definição estipulada pela Organização Mundial do Turismo. Os resultados alcançados demonstraram que os indicadores estudados são instrumentos a serem considerados no processo de avaliação e quantificação do turismo em um destino com semelhantes configurações ambientais, o que viabiliza a compreensão e o fortalecimento da noção de sustentabilidade. Este estudo caracteriza-se pela sua vertente interdisciplinar e teve como norteador o método dedutivo. / Tese (Doutorado em Tecnologia Nuclear) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP

<div>Adsorbent technology is widely used in many industrial applications including waste heat recovery, water purification, and atmospheric revitalization in confined habitations. Astronauts depend on adsorbent-based systems to remove metabolic carbon dioxide (CO₂) from the cabin atmosphere; as NASA prepares for the journey to Mars, engineers are redesigning the adsorbent-based system for reduced weight and optimal efficiency. These efforts hinge upon the development of accurate, predictive models, as simulations are increasingly relied upon to save cost and time over the traditional design-build-test approach. Engineers rely on simplified models to reduce computational cost and enable parametric optimizations. Amongst these simplified models is the axially dispersed plug-flow model for predicting the adsorbate concentration during flow through an adsorbent bed. This model is ubiquitously used in designing fixed-bed adsorption systems. The current work aims to improve the accuracy of the axially dispersed plug-flow model because of its wide-spread use. This dissertation identifies the critical model inputs that drive the overall uncertainty in important output quantities then systematically improves the measurement and prediction of these input parameters. Limitations of the axially dispersed plug-flow model are also discussed, and recommendations made for identifying failure of the plug-flow assumption.</div><div><br></div><div>An uncertainty and sensitivity analysis of an axially disperse plug-flow model is first presented. Upper and lower uncertainty bounds for each of the model inputs are found by comparing empirical correlations against experimental data from the literature. Model uncertainty is then investigated by independently varying each model input between its individual upper and lower uncertainty bounds then observing the relative change in predicted effluent concentration and temperature (<i>e.g.</i>, breakthrough time, bed capacity, and effluent temperature). This analysis showed that the LDF mass transfer coefficient is the largest source of uncertainty. Furthermore, the uncertainty analysis reveals that ignoring the effect of wall-channeling on apparent axial dispersion can cause significant error in the predicted breakthrough times of small-diameter beds.</div><div><br></div><div>In addition to LDF mass transfer coefficient and axial-dispersion, equilibrium isotherms are known to be strong lever arms and a potentially dominant source of model error. As such, detailed analysis of the equilibrium adsorption isotherms for zeolite 13X was conducted to improve the fidelity of CO₂ and H₂O on equilibrium isotherms compared to extant data. These two adsorbent/adsorbate pairs are of great interest as NASA plans to use zeolite 13X in the next generation atmospheric revitalization system. Equilibrium isotherms describe a sorbent’s maximum capacity at a given temperature and adsorbate (<i>e.g.</i>, CO₂ or H₂O) partial pressure. New isotherm data from NASA Ames Research Center and NASA Marshall Space Flight Center for CO₂ and H₂O adsorption on zeolite 13X are presented. These measurements were carefully collected to eliminate sources of bias in previous data from the literature, where incomplete activation resulted in a reduced capacity. Several models are fit to the new equilibrium isotherm data and recommendations of the best model fit are made. The best-fit isotherm models from this analysis are used in all subsequent modeling efforts discussed in this dissertation.</div><div><br></div><div>The last two chapters examine the limitations of the axially disperse plug-flow model for predicting breakthrough in confined geometries. When a bed of pellets is confined in a rigid container, packing heterogeneities near the wall lead to faster flow around the periphery of the bed (<i>i.e.</i>, wall channeling). Wall-channeling effects have long been considered negligible for beds which hold more than 20 pellets across; however, the present work shows that neglecting wall-channeling effects on dispersion can yield significant errors in model predictions. There is a fundamental gap in understanding the mechanisms which control wall-channeling driven dispersion. Furthermore, there is currently no way to predict wall channeling effects a priori or even to identify what systems will be impacted by it. This dissertation aims to fill this gap using both experimental measurements and simulations to identify mechanisms which cause the plug-flow assumption to fail.</div><div><br></div><div>First, experimental evidence of wall-channeling in beds, even at large bed-to-pellet diameter ratios (<i>d</i>_bed/<i>d</i>_p=48) is presented. These experiments are then used to validate a method for accurately extracting mass transfer coefficients from data affected by significant wall channeling. The relative magnitudes of wall-channeling effects are shown to be a function of the adsorption/adsorbate pair and geometric confinement (<i>i.e.</i>, bed size). Ultimately, the axially disperse plug-flow model fails to capture the physics of breakthrough when nonplug-flow conditions prevail in the bed.</div><div><br></div><div>The final chapter of this dissertation develops a two-dimensional (2-D) adsorption model to examine the interplay of wall-channeling and adsorption kinetics and the adsorbent equilibrium capacity on breakthrough in confined geometries. The 2-D model incorporates the effect of radial variations in porosity on the velocity profile and is shown to accurately capture the effect of wall-channeling on adsorption behavior. The 2-D model is validated against experimental data, and then used to investigate whether capacity or adsorption kinetics cause certain adsorbates to exhibit more significant radial variations in concentration compared than others. This work explains channeling effects can vary for different adsorbate and/or adsorbent pairs—even under otherwise identical conditions—and highlights the importance of considering adsorption kinetics in addition to the traditional <i>d</i>_bed/<i>d</i>_p criteria.</div><div><br></div><div>This dissertation investigates key gaps in our understanding of fixed-bed adsorption. It will deliver insight into how these missing pieces impact the accuracy of predictive models and provide a means for reconciling these errors. The culmination of this work will be an accurate, predictive model that assists in the simulation-based design of the next-generation atmospheric revitalization system for humans’ journey to Mars.</div>

Les challenges posés par les missions d’exploration du système solaire sont très différents de ceux de la Station Spatiale Internationale, puisque les distances sont beaucoup plus importantes, limitant la possibilité de ravitaillements réguliers. Les systèmes support-vie basés sur des plantes supérieures et des micro-organismes, comme le projet de l’Agence Spatiale Européenne (ESA) MELiSSA (Micro Ecological Life Support System Alternative) permettront aux équipages d’être autonomes en termes de production de nourriture, revitalisation de l’air et de recyclage d’eau, tout en fermant les cycles de l’eau, de l’oxygène, de l’azote et du carbone, pendant les missions longue durée, et deviendront donc essentiels.La croissance et le développement des plantes et autres organismes biologiques sont fortement influencés par les conditions environnementales (par exemple la gravité, la pression, la température, l’humidité relative, les pressions partielles en O2 et CO2). Pour prédire la croissance des plantes dans ces conditions non-standard, il est crucial de développer des modèles de croissance mécanistiques, permettant une étude multi-échelle des différents phénomènes, ainsi que d’acquérir une compréhension approfondie de tous les processus impliqués dans le développement des plantes en environnement de gravité réduite et d’identifier les lacunes de connaissance.En particulier, les échanges gazeux à la surface de la feuille sont altérés en gravité réduite, ce qui pourrait diminuer la croissance des plantes dans l’espace. Ainsi, nous avons étudié les relations complexes entre convection forcée, niveau de gravité et production de biomasse et avons trouvé que l’inclusion de la gravité comme paramètre dans les modèles d’échanges gazeux des plantes nécessite une description précise des transferts de matière et d’énergie dans la couche limite. Nous avons ajouté un bilan d’énergie au bilan de masse du modèle de croissance de plante déjà existant et cela a ajouté des variations temporelles sur la température de surface des feuilles.Cette variable peut être mesurée à l’aide de caméras infra-rouges et nous avons réalisé une expérience en vol parabolique et cela nous a permis de valider des modèles de transferts gazeux locaux en 0g et 2g, sans ventilation.Enfin, le transport de sève, la croissance racinaire et la sénescence des feuilles doivent être étudiés en conditions de gravité réduite. Cela permettrait de lier notre modèle d’échanges gazeux à la morphologie des plantes et aux allocations de ressources dans une plante et ainsi arriver à un modèle mécanistique complet de la croissance des plantes en environnement de gravité réduite. / Challenges triggered by human space exploration of the solar system are different from those of the International Space Station because distances and time frames are of a different scale, preventing frequent resupplies. Bioregenerative life-support systems based on higher plants and microorganisms, such as the ESA Micro-Ecological Life Support System Alternative (MELiSSA) project will enable crews to be autonomous in food production, air revitalization, and water recycling, while closing cycles for water, oxygen, nitrogen, and carbon, during long-duration missions and will thus become necessary.The growth and development of higher plants and other biological organisms are strongly influenced by environmental conditions (e.g. gravity, pressure, temperature, relative humidity, partial pressure of O2 or CO2). To predict plant growth in these non-standard conditions, it is crucial to develop mechanistic models of plant growth, enabling multi-scale study of different phenomena, as well as gaining thorough understanding on all processes involved in plant development in low gravity environment and identifying knowledge gaps.Especially gas exchanges at the leaf surface are altered in reduced gravity, which could reduce plant growth in space. Thus, we studied the intricate relationships between forced convection, gravity levels and biomass production and found that the inclusion of gravity as a parameter in plant gas exchanges models requires accurate mass and heat transfer descriptions in the boundary layer. We introduced an energy coupling to the already existing mass balance model of plant growth and this introduced time-dependent variations of the leaf surface temperature.This variable can be measured using infra-red cameras and we implemented a parabolic flight experiment, which enabled us to validate local gas transfer models in 0g and 2g without ventilation.Finally, sap transport needs to be studied in reduced gravity environments, along with root absorption and leaf senescence. This would enable to link our gas exchanges model to plant morphology and resources allocations, and achieve a complete mechanistic model of plant growth in low gravity environments.