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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Improving the performance of software-defined networks using dynamic flow installation and management techniques

Isaia, Philippos January 2018 (has links)
As computer networks evolve, they become more complex, introducing several challenges in the areas of performance and management. Such problems can lead to stagnation in network innovation. Software Defined Networks (SDN) framework could be one of the best candidates for improving and revolutionising networking by giving the full control to the network administrators to implement new management and performance optimisation techniques. This thesis examines performance issues faced in SDN due to the introduction of the SDN Controller. These issues include the extra delay due to the round-trip time between the switch and the controller as well as the fact that some packets arrive at the destination out-of-order. We propose a novel dynamic flow installation and management algorithm (OFPE) using the SDN protocol OpenFlow, which preserves the controller to a non-overloaded CPU state and allow it to dynamically add and adjust flow table rules to reduce packet delay and out-of-order packets. In addition, we propose OFPEX, an extension to OFPE algorithm that includes techniques for managing multi-switch environments as well as methods that make use of the packets interarrival time in categorising and serving packet flows. Such techniques allow topology awareness, helping the controller to install flow table rules in such a way to form optimal routes for high priority flows thus increasing network performance. For the performance evaluation of the proposed algorithms, both hardware testbed as well as emulation experiments have been conducted. The performance results indicate that OFPE algorithm achieves a significant enhancement in performance in the form of reduced delay by up to 92.56% (depending on the scenario), reduced packet loss by up to 55.32% and reduced out-of-order packets by up to 69.44%. Furthermore, we propose a novel placement algorithm for distributed Mininet implementations which uses weights in order to distribute the experiment components to the appropriately distributed machines. The proposed algorithm uses static code analysis in order to examine the experimental code as well as it measures the capabilities of physical components in order to create a weights table which is then used to distribute the experiment components properly. The performance results of the proposed algorithm evaluation indicated reductions in delay and packet loss of up to 65.51% and 86.35% respectively, as well as a decrease in the standard deviation of CPU usage by up to 88.63%. These results indicate that the proposed algorithm distributes the experiment components evenly across the available resources. Finally, we propose a series of Benchmarking tests that can be used to rate all the available SDN experimental platforms. These tests allow the selection of the appropriate experimental platform according to the scenario needs as well as they indicate the resources needed by each platform.
2

Development and Initial Testing of a Micro-Newton Torsion Pendulum with Gas-Dynamic Calibration

Smith, Brandon Joseph 05 March 2019 (has links)
A novel torsion pendulum thrust test stand for micro-Newton-scale spacecraft thrusters is described. The stand is designed to be robust against electromagnetic interference effects internal or external to the thruster being tested. The design and testing of a gas-dynamic calibration thruster is included. This thruster is fully self-contained on the pendulum arm, with no external wires or feedlines connected to the device and impacting the dynamic response of the underlying pendulum. Initial calibration results are shown. Zero drift and hysteresis are present in the results, evidenced by a constant steady-state displacement drift and a return to a different displacement after shutdown of the calibration thruster. Results are compared to theoretical solutions of the equation of motion. An external forcing function of facility effects is described for discrepancies between results and the theoretical solution. Further work to eliminate these effects and add damping are proposed. / MS / Many recently proposed space missions require very fine vehicle attitude and position control in support of their science objectives. Thrusters with the ability to provide this control are currently in development, from laboratory proofs of concept to initial test flights on pathfinding missions. The low levels of thrust produced by these devices, in the range of less than the weight of a mosquito, require specialized test stands with very fine resolution. This thesis describes a novel torsion pendulum design for measuring these thrusters as well as initial validation results from its calibration system using rarefied gas flow. This calibration device is fully-contained on the device’s arm, removing many common sources of compensation factors which are often needed for other test stand designs. A custom-built displacement measuring system for determining angular motion of the pendulum arm is described which allows for measuring angular displacements of the arm to the level of arcseconds and potentially fractions thereof. Initial results suggest measurement of the expected levels of thrust, while some work remains to remove lingering sources of error and achieve more precise thrust data.
3

核融合プラズマにおける粘性と動的流れの影響を受けた抵抗性ティアリングモードによる突発的磁気リコネクションに関する研究 / Study of impulsive magnetic reconnection due to resistive tearing mode with the effect of viscosity and dynamic flow in fusion plasmas

AHMAD, ALI 23 March 2015 (has links)
Kyoto University (京都大学) / 0048 / 新制・課程博士 / 博士(エネルギー科学) / 甲第19091号 / エネ博第315号 / 新制||エネ||64 / 32042 / 京都大学大学院エネルギー科学研究科エネルギー基礎科学専攻 / (主査)教授 岸本 泰明, 教授 前川 孝, 教授 中村 祐司 / 学位規則第4条第1項該当
4

Study of impulsive magnetic reconnection due to resistive tearing mode with the effect of viscosity and dynamic flow in fusion plasmas / 核融合プラズマにおける粘性と動的流れの影響を受けた抵抗性ティアリングモードによる突発的磁気リコネクションに関する研究

AHMAD, ALI 23 March 2015 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(エネルギー科学) / 甲第19091号 / エネ博第315号 / 新制||エネ||64(附属図書館) / 32042 / 京都大学大学院エネルギー科学研究科エネルギー基礎科学専攻 / (主査)教授 岸本 泰明, 教授 前川 孝, 教授 中村 祐司 / 学位規則第4条第1項該当 / Doctor of Energy Science / Kyoto University / DFAM
5

NANOPARTICLE DEPOSITION AND DOSIMETRY FOR IN VITRO TOXICOLOGY

Grabinski, Christin M. 03 June 2015 (has links)
No description available.
6

Variabilidade espacial no Sistema Aquífero Guarani : controles estratigráficos e estruturais

Soares, Ana Paula January 2008 (has links)
A funcionalidade de um sistema aqüífero é dependente dos atributos do reservatório, em especial as suas heterogeneidades, associadas às propriedades intrínsecas da rocha e descontinuidades relacionadas à compartimentação estrutural. O presente estudo teve como objetivo principal identificar e mapear a organização espacial dos componentes estratigráficos e compartimentos estruturais do Sistema Aqüífero Guarani, localizado na bacia do Paraná, a fim de verificar os efeitos na sua distribuição na organização e funci- onalidade. Foram observadas as variações na salinidade, as zonas de recarga e de des- carga, visando contribuir para os estudos que estabelecem prioridades de uso, mapea- mento, monitoramento e redução das atividades potencialmente contaminantes. A extensa seção siliciclástica do aqüífero foi formada por sistemas deposicionais eólicos e fluviais, de idade triássica e jurássica, englobados principalmente pelas forma- ções Pirambóia e Botucatu (Brasil), Misiones (Paraguai e Argentina) e Taquarembó (Uruguai). Levantamentos de seções estratigráficas ao longo da faixa de afloramentos e análise e interpretação de perfis geofísicos de poços para petróleo na bacia permitiram compor um novo quadro estratigráfico para o sistema aqüífero. A compartimentação estrutural do aqüífero foi definida a partir da integração de mapas morfoestruturais previamente publicados, traçados por interpretação de imagens de radar, satelitárias, modelos digitais de elevação e mapas regionais aeromagnetométri- cos e gravimétricos. Um novo mapa de lineamentos estruturais, interpretado a partir de um modelo digital de terreno, teve a precisão avaliada por comparação com mapas pré- vios gerados por diferentes autores e métodos. A sucessão sedimentar que compõe o aqüífero é objeto de diferentes correlações e classificações estratigráficas, com implicações na organização das unidades hidroestrati- gráficas. Caracteriza-se por associações de fácies cujos elementos arquiteturais e geo- metria permitem subdividí-lo em unidades de fluxo. Três unidades de fluxo principais foram reconhecidas, identificadas e denominadas conforme a fácies genética: duna (DU), interdunas (ID) e canais (CH). Secundariamente, duas outras unidades: crevasse (CR), lacustre e planície de inundação (FF) ambém foram identificadas. Estas unidades apresentam diferentes condutividade hidráulica e desempenham, conseqüentemente, papéis diferentes no funcionamento do aqüífero. Para as unidades de fluxo foi possível estimar a condutividade hidráulica média com base na seleção e tamanho médio dos grãos e na argilosidade dos sedimentos. Em termos de litoestratigrafia, o SAG é composto pelas formações Santa Maria, de ocorrência restrita ao Rio Grande do Sul, espacialmente sotoposta e justaposta às forma- ções flúvio-eólicas Guará (No oeste do Rio Grande do sul) e Pirambóia (leste do Rio Grande do Sul, e toda a parte central e norte da Bacia do Paraná). Todas estão extensa- mente superpostas, ora discordantemente, ora transicionalmente, pela Formação Botu- catu, caracterizada por depósitos dunares de desertos super-áridos. Tal fácies apresenta grande homogeneidade, boa porosidade e permeabilidade efetiva, caracterizando-se como a mais importante unidade hidroestratigráfica. Na interpolação dos contornos estruturais e espessuras das rochas do aqüífero, os lineamentos reconhecidos revelaram grandes blocos tectônicos que restringem o fluxo e a formação de células hidrogeológicas. A anisotropia sedimentar e a compartimentação estrutural foram consideradas na avaliação das unidades de fluxo e do sistema e no cál- culo do fluxo potencial dinâmico. Mapas de fluxo potencial e de direção de fluxo perm- tem visualizar a forte influência estrutural nas áreas preferenciais de recarga e descarga e os controles das entradas e saídas do sistema. A distribuição espacial das unidades mostra o zoneamento dos valores de condutividade hidráulica, com efeito direto na qua- lidade e na condutividade do fluxo da água dentro do aqüífero regional. Como resultado, conclui-se que apesar de se constituir um reservatório idealmente contínuo, a compartimentação e diferenciação interna do Sistema Aqüífero Guarani apon- tam para uma complexidade que parece ultrapassar a concepção de um sistema único. / The functionality of an aquifer system depends on attributes of the reservoir, spe- cially those heterogeneities associated to intrinsic properties of the rock and to structural compartmentation discontinuities. The main objective of the study was to identify and to map the stratigraphic components and structural compartments of the Guarani Aquifer System, located in the Paraná Basin, to verify the effect of their distribution on the aquifer organization and functionality. Variations in the salinity, the discharge and recharge zones were also studied as a contribution to the studies that aim to establish priorities in the use, mapping, monitoring and in the reduction of potentially contami- nant activities. The extensive siliciclastic section, with a maximum thickness of 600 m, was formed by aeolian and fluvial depositional systems of Triassic and Jurassic age and referred to mainly as the Pirambóia and Botucatu (Brazil), Misiones (Paraguay and Argentina) and Taquarembó (Uruguay) formations. Survey of stratigraphic sections throughout the out- crop belt and analysis and interpretation of geophysical profiles of wells drilled for oil in the basin had allowed a new stratigraphic and structural picture of the water-bearing system to be drawn. The structural compartmentation of the aquifer was defined based on the integration of morphostructural maps previously published, traced from interpretation of radar and satellite images, digital terrain models of rise and aeromagnetometric and gravimetric regional maps. A new map of structural lineaments, interpreted from a digital elevation model, had its precision and accuracy evaluated by comparint it to previous maps gener- ated by different authors and methods. The sedimentary succession that form the water-bearing unit is object of different correlations and stratigraphic classifications – with implications in the spatial configura- tion and regional connectivity of the hydrostratigraphic units. The succession is charac- terized by associations of facies whose architectural elements and geometry allow it to be subdivided in units of flow. Three main units of flow were recognized, identified and referred to as genetic facies: dune (DU), interdune (ID) and canals (CH). Secondarily, two other units: flooding plain crevasse (CR), lacustrine and (FF) were identified. These units show different hydraulic conductivities and play, consequently, different roles in the functioning of the aquifer. For the units of flow, it was possible estimate the average hydraulic conductivity on the basis of the selection and average size of its grains and in the mud content of the sediments. In litostratigraphic terms, the Guarani Aquifer System is represented by the forma- tions Santa Maria, restricted to Rio Grande do Sul state, bellow and spatially justaposed to the fluvial-aeolian formations Guará (in western Rio Grande do Sul) and Pirambóia (eastern Rio Grande do Sul, and all the central and north parts of the Paraná Basin). All units are extensively superposed, in some places unconformably, in other places transi- tionally, by the Botucatu Formation, which is characterized by dune deposits of super- arid deserts. Such facies present a great homogeneity, a good porosity and permeability, being the most important hydrostratigraphic unit. In the interpolation of the structural contours and thicknesses of the rocks of the water-bearing unit, the recognized lineaments revealed large tectonic blocks that restrict the flow and the formation of hydrogeologic cells. The sedimentary anisotropy and the structural compartments have been considered in the evaluation of the units of flow and the system and in the calculation of the dynamic potential flow. The obtained potential flow and direction of flow maps allowed the strong structural influence in the preferen- tial areas of recharge and discharge and the controls of the inputs and outputs of the sys- tem to be identified. The spatial distribution of the units shows a hydraulic conductivity zoning with direct effect in the quality and the regional conductivity. As result, it can be concluded that although it consists of an ideally continuous reservoir, the compartmentation and the internal differentiation of the Guarani Aquifer System point to a complexity that seems to exceed the conception of a single system.
7

Variabilidade espacial no Sistema Aquífero Guarani : controles estratigráficos e estruturais

Soares, Ana Paula January 2008 (has links)
A funcionalidade de um sistema aqüífero é dependente dos atributos do reservatório, em especial as suas heterogeneidades, associadas às propriedades intrínsecas da rocha e descontinuidades relacionadas à compartimentação estrutural. O presente estudo teve como objetivo principal identificar e mapear a organização espacial dos componentes estratigráficos e compartimentos estruturais do Sistema Aqüífero Guarani, localizado na bacia do Paraná, a fim de verificar os efeitos na sua distribuição na organização e funci- onalidade. Foram observadas as variações na salinidade, as zonas de recarga e de des- carga, visando contribuir para os estudos que estabelecem prioridades de uso, mapea- mento, monitoramento e redução das atividades potencialmente contaminantes. A extensa seção siliciclástica do aqüífero foi formada por sistemas deposicionais eólicos e fluviais, de idade triássica e jurássica, englobados principalmente pelas forma- ções Pirambóia e Botucatu (Brasil), Misiones (Paraguai e Argentina) e Taquarembó (Uruguai). Levantamentos de seções estratigráficas ao longo da faixa de afloramentos e análise e interpretação de perfis geofísicos de poços para petróleo na bacia permitiram compor um novo quadro estratigráfico para o sistema aqüífero. A compartimentação estrutural do aqüífero foi definida a partir da integração de mapas morfoestruturais previamente publicados, traçados por interpretação de imagens de radar, satelitárias, modelos digitais de elevação e mapas regionais aeromagnetométri- cos e gravimétricos. Um novo mapa de lineamentos estruturais, interpretado a partir de um modelo digital de terreno, teve a precisão avaliada por comparação com mapas pré- vios gerados por diferentes autores e métodos. A sucessão sedimentar que compõe o aqüífero é objeto de diferentes correlações e classificações estratigráficas, com implicações na organização das unidades hidroestrati- gráficas. Caracteriza-se por associações de fácies cujos elementos arquiteturais e geo- metria permitem subdividí-lo em unidades de fluxo. Três unidades de fluxo principais foram reconhecidas, identificadas e denominadas conforme a fácies genética: duna (DU), interdunas (ID) e canais (CH). Secundariamente, duas outras unidades: crevasse (CR), lacustre e planície de inundação (FF) ambém foram identificadas. Estas unidades apresentam diferentes condutividade hidráulica e desempenham, conseqüentemente, papéis diferentes no funcionamento do aqüífero. Para as unidades de fluxo foi possível estimar a condutividade hidráulica média com base na seleção e tamanho médio dos grãos e na argilosidade dos sedimentos. Em termos de litoestratigrafia, o SAG é composto pelas formações Santa Maria, de ocorrência restrita ao Rio Grande do Sul, espacialmente sotoposta e justaposta às forma- ções flúvio-eólicas Guará (No oeste do Rio Grande do sul) e Pirambóia (leste do Rio Grande do Sul, e toda a parte central e norte da Bacia do Paraná). Todas estão extensa- mente superpostas, ora discordantemente, ora transicionalmente, pela Formação Botu- catu, caracterizada por depósitos dunares de desertos super-áridos. Tal fácies apresenta grande homogeneidade, boa porosidade e permeabilidade efetiva, caracterizando-se como a mais importante unidade hidroestratigráfica. Na interpolação dos contornos estruturais e espessuras das rochas do aqüífero, os lineamentos reconhecidos revelaram grandes blocos tectônicos que restringem o fluxo e a formação de células hidrogeológicas. A anisotropia sedimentar e a compartimentação estrutural foram consideradas na avaliação das unidades de fluxo e do sistema e no cál- culo do fluxo potencial dinâmico. Mapas de fluxo potencial e de direção de fluxo perm- tem visualizar a forte influência estrutural nas áreas preferenciais de recarga e descarga e os controles das entradas e saídas do sistema. A distribuição espacial das unidades mostra o zoneamento dos valores de condutividade hidráulica, com efeito direto na qua- lidade e na condutividade do fluxo da água dentro do aqüífero regional. Como resultado, conclui-se que apesar de se constituir um reservatório idealmente contínuo, a compartimentação e diferenciação interna do Sistema Aqüífero Guarani apon- tam para uma complexidade que parece ultrapassar a concepção de um sistema único. / The functionality of an aquifer system depends on attributes of the reservoir, spe- cially those heterogeneities associated to intrinsic properties of the rock and to structural compartmentation discontinuities. The main objective of the study was to identify and to map the stratigraphic components and structural compartments of the Guarani Aquifer System, located in the Paraná Basin, to verify the effect of their distribution on the aquifer organization and functionality. Variations in the salinity, the discharge and recharge zones were also studied as a contribution to the studies that aim to establish priorities in the use, mapping, monitoring and in the reduction of potentially contami- nant activities. The extensive siliciclastic section, with a maximum thickness of 600 m, was formed by aeolian and fluvial depositional systems of Triassic and Jurassic age and referred to mainly as the Pirambóia and Botucatu (Brazil), Misiones (Paraguay and Argentina) and Taquarembó (Uruguay) formations. Survey of stratigraphic sections throughout the out- crop belt and analysis and interpretation of geophysical profiles of wells drilled for oil in the basin had allowed a new stratigraphic and structural picture of the water-bearing system to be drawn. The structural compartmentation of the aquifer was defined based on the integration of morphostructural maps previously published, traced from interpretation of radar and satellite images, digital terrain models of rise and aeromagnetometric and gravimetric regional maps. A new map of structural lineaments, interpreted from a digital elevation model, had its precision and accuracy evaluated by comparint it to previous maps gener- ated by different authors and methods. The sedimentary succession that form the water-bearing unit is object of different correlations and stratigraphic classifications – with implications in the spatial configura- tion and regional connectivity of the hydrostratigraphic units. The succession is charac- terized by associations of facies whose architectural elements and geometry allow it to be subdivided in units of flow. Three main units of flow were recognized, identified and referred to as genetic facies: dune (DU), interdune (ID) and canals (CH). Secondarily, two other units: flooding plain crevasse (CR), lacustrine and (FF) were identified. These units show different hydraulic conductivities and play, consequently, different roles in the functioning of the aquifer. For the units of flow, it was possible estimate the average hydraulic conductivity on the basis of the selection and average size of its grains and in the mud content of the sediments. In litostratigraphic terms, the Guarani Aquifer System is represented by the forma- tions Santa Maria, restricted to Rio Grande do Sul state, bellow and spatially justaposed to the fluvial-aeolian formations Guará (in western Rio Grande do Sul) and Pirambóia (eastern Rio Grande do Sul, and all the central and north parts of the Paraná Basin). All units are extensively superposed, in some places unconformably, in other places transi- tionally, by the Botucatu Formation, which is characterized by dune deposits of super- arid deserts. Such facies present a great homogeneity, a good porosity and permeability, being the most important hydrostratigraphic unit. In the interpolation of the structural contours and thicknesses of the rocks of the water-bearing unit, the recognized lineaments revealed large tectonic blocks that restrict the flow and the formation of hydrogeologic cells. The sedimentary anisotropy and the structural compartments have been considered in the evaluation of the units of flow and the system and in the calculation of the dynamic potential flow. The obtained potential flow and direction of flow maps allowed the strong structural influence in the preferen- tial areas of recharge and discharge and the controls of the inputs and outputs of the sys- tem to be identified. The spatial distribution of the units shows a hydraulic conductivity zoning with direct effect in the quality and the regional conductivity. As result, it can be concluded that although it consists of an ideally continuous reservoir, the compartmentation and the internal differentiation of the Guarani Aquifer System point to a complexity that seems to exceed the conception of a single system.
8

Variabilidade espacial no Sistema Aquífero Guarani : controles estratigráficos e estruturais

Soares, Ana Paula January 2008 (has links)
A funcionalidade de um sistema aqüífero é dependente dos atributos do reservatório, em especial as suas heterogeneidades, associadas às propriedades intrínsecas da rocha e descontinuidades relacionadas à compartimentação estrutural. O presente estudo teve como objetivo principal identificar e mapear a organização espacial dos componentes estratigráficos e compartimentos estruturais do Sistema Aqüífero Guarani, localizado na bacia do Paraná, a fim de verificar os efeitos na sua distribuição na organização e funci- onalidade. Foram observadas as variações na salinidade, as zonas de recarga e de des- carga, visando contribuir para os estudos que estabelecem prioridades de uso, mapea- mento, monitoramento e redução das atividades potencialmente contaminantes. A extensa seção siliciclástica do aqüífero foi formada por sistemas deposicionais eólicos e fluviais, de idade triássica e jurássica, englobados principalmente pelas forma- ções Pirambóia e Botucatu (Brasil), Misiones (Paraguai e Argentina) e Taquarembó (Uruguai). Levantamentos de seções estratigráficas ao longo da faixa de afloramentos e análise e interpretação de perfis geofísicos de poços para petróleo na bacia permitiram compor um novo quadro estratigráfico para o sistema aqüífero. A compartimentação estrutural do aqüífero foi definida a partir da integração de mapas morfoestruturais previamente publicados, traçados por interpretação de imagens de radar, satelitárias, modelos digitais de elevação e mapas regionais aeromagnetométri- cos e gravimétricos. Um novo mapa de lineamentos estruturais, interpretado a partir de um modelo digital de terreno, teve a precisão avaliada por comparação com mapas pré- vios gerados por diferentes autores e métodos. A sucessão sedimentar que compõe o aqüífero é objeto de diferentes correlações e classificações estratigráficas, com implicações na organização das unidades hidroestrati- gráficas. Caracteriza-se por associações de fácies cujos elementos arquiteturais e geo- metria permitem subdividí-lo em unidades de fluxo. Três unidades de fluxo principais foram reconhecidas, identificadas e denominadas conforme a fácies genética: duna (DU), interdunas (ID) e canais (CH). Secundariamente, duas outras unidades: crevasse (CR), lacustre e planície de inundação (FF) ambém foram identificadas. Estas unidades apresentam diferentes condutividade hidráulica e desempenham, conseqüentemente, papéis diferentes no funcionamento do aqüífero. Para as unidades de fluxo foi possível estimar a condutividade hidráulica média com base na seleção e tamanho médio dos grãos e na argilosidade dos sedimentos. Em termos de litoestratigrafia, o SAG é composto pelas formações Santa Maria, de ocorrência restrita ao Rio Grande do Sul, espacialmente sotoposta e justaposta às forma- ções flúvio-eólicas Guará (No oeste do Rio Grande do sul) e Pirambóia (leste do Rio Grande do Sul, e toda a parte central e norte da Bacia do Paraná). Todas estão extensa- mente superpostas, ora discordantemente, ora transicionalmente, pela Formação Botu- catu, caracterizada por depósitos dunares de desertos super-áridos. Tal fácies apresenta grande homogeneidade, boa porosidade e permeabilidade efetiva, caracterizando-se como a mais importante unidade hidroestratigráfica. Na interpolação dos contornos estruturais e espessuras das rochas do aqüífero, os lineamentos reconhecidos revelaram grandes blocos tectônicos que restringem o fluxo e a formação de células hidrogeológicas. A anisotropia sedimentar e a compartimentação estrutural foram consideradas na avaliação das unidades de fluxo e do sistema e no cál- culo do fluxo potencial dinâmico. Mapas de fluxo potencial e de direção de fluxo perm- tem visualizar a forte influência estrutural nas áreas preferenciais de recarga e descarga e os controles das entradas e saídas do sistema. A distribuição espacial das unidades mostra o zoneamento dos valores de condutividade hidráulica, com efeito direto na qua- lidade e na condutividade do fluxo da água dentro do aqüífero regional. Como resultado, conclui-se que apesar de se constituir um reservatório idealmente contínuo, a compartimentação e diferenciação interna do Sistema Aqüífero Guarani apon- tam para uma complexidade que parece ultrapassar a concepção de um sistema único. / The functionality of an aquifer system depends on attributes of the reservoir, spe- cially those heterogeneities associated to intrinsic properties of the rock and to structural compartmentation discontinuities. The main objective of the study was to identify and to map the stratigraphic components and structural compartments of the Guarani Aquifer System, located in the Paraná Basin, to verify the effect of their distribution on the aquifer organization and functionality. Variations in the salinity, the discharge and recharge zones were also studied as a contribution to the studies that aim to establish priorities in the use, mapping, monitoring and in the reduction of potentially contami- nant activities. The extensive siliciclastic section, with a maximum thickness of 600 m, was formed by aeolian and fluvial depositional systems of Triassic and Jurassic age and referred to mainly as the Pirambóia and Botucatu (Brazil), Misiones (Paraguay and Argentina) and Taquarembó (Uruguay) formations. Survey of stratigraphic sections throughout the out- crop belt and analysis and interpretation of geophysical profiles of wells drilled for oil in the basin had allowed a new stratigraphic and structural picture of the water-bearing system to be drawn. The structural compartmentation of the aquifer was defined based on the integration of morphostructural maps previously published, traced from interpretation of radar and satellite images, digital terrain models of rise and aeromagnetometric and gravimetric regional maps. A new map of structural lineaments, interpreted from a digital elevation model, had its precision and accuracy evaluated by comparint it to previous maps gener- ated by different authors and methods. The sedimentary succession that form the water-bearing unit is object of different correlations and stratigraphic classifications – with implications in the spatial configura- tion and regional connectivity of the hydrostratigraphic units. The succession is charac- terized by associations of facies whose architectural elements and geometry allow it to be subdivided in units of flow. Three main units of flow were recognized, identified and referred to as genetic facies: dune (DU), interdune (ID) and canals (CH). Secondarily, two other units: flooding plain crevasse (CR), lacustrine and (FF) were identified. These units show different hydraulic conductivities and play, consequently, different roles in the functioning of the aquifer. For the units of flow, it was possible estimate the average hydraulic conductivity on the basis of the selection and average size of its grains and in the mud content of the sediments. In litostratigraphic terms, the Guarani Aquifer System is represented by the forma- tions Santa Maria, restricted to Rio Grande do Sul state, bellow and spatially justaposed to the fluvial-aeolian formations Guará (in western Rio Grande do Sul) and Pirambóia (eastern Rio Grande do Sul, and all the central and north parts of the Paraná Basin). All units are extensively superposed, in some places unconformably, in other places transi- tionally, by the Botucatu Formation, which is characterized by dune deposits of super- arid deserts. Such facies present a great homogeneity, a good porosity and permeability, being the most important hydrostratigraphic unit. In the interpolation of the structural contours and thicknesses of the rocks of the water-bearing unit, the recognized lineaments revealed large tectonic blocks that restrict the flow and the formation of hydrogeologic cells. The sedimentary anisotropy and the structural compartments have been considered in the evaluation of the units of flow and the system and in the calculation of the dynamic potential flow. The obtained potential flow and direction of flow maps allowed the strong structural influence in the preferen- tial areas of recharge and discharge and the controls of the inputs and outputs of the sys- tem to be identified. The spatial distribution of the units shows a hydraulic conductivity zoning with direct effect in the quality and the regional conductivity. As result, it can be concluded that although it consists of an ideally continuous reservoir, the compartmentation and the internal differentiation of the Guarani Aquifer System point to a complexity that seems to exceed the conception of a single system.
9

Enhanced Physiological Microenvironment for Improved Evaluation of Nanoparticle Behavior

Breitner, Emily Katherine 27 August 2015 (has links)
No description available.
10

Visual Flow Analysis and Saliency Prediction

Srinivas, Kruthiventi S S January 2016 (has links) (PDF)
Nowadays, we have millions of cameras in public places such as traffic junctions, railway stations etc., and capturing video data round the clock. This humongous data has resulted in an increased need for automation of visual surveillance. Analysis of crowd and traffic flows is an important step towards achieving this goal. In this work, we present our algorithms for identifying and segmenting dominant ows in surveillance scenarios. In the second part, we present our work aiming at predicting the visual saliency. The ability of humans to discriminate and selectively pay attention to few regions in the scene over the others is a key attentional mechanism. Here, we present our algorithms for predicting human eye fixations and segmenting salient objects in the scene. (i) Flow Analysis in Surveillance Videos: We propose algorithms for segmenting flows of static and dynamic nature in surveillance videos in an unsupervised manner. In static flows scenarios, we assume the motion patterns to be consistent over the entire duration of video and analyze them in the compressed domain using H.264 motion vectors. Our approach is based on modeling the motion vector field as a Conditional Random Field (CRF) and obtaining oriented motion segments which are merged to obtain the final flow segments. This approach in compressed domain is shown to be both accurate and computationally efficient. In the case of dynamic flow videos (e.g. flows at a traffic junction), we propose a method for segmenting the individual object flows over long durations. This long-term flow segmentation is achieved in the framework of CRF using local color and motion features. We propose a Dynamic Time Warping (DTW) based distance measure between flow segments for clustering them and generate representative dominant ow models. Using these dominant flow models, we perform path prediction for the vehicles entering the camera's field-of-view and detect anomalous motions. (ii) Visual Saliency Prediction using Deep Convolutional Neural Networks: We propose a deep fully convolutional neural network (CNN) - DeepFix, for accurately predicting eye fixations in the form of saliency maps. Unlike classical works which characterize the saliency map using various hand-crafted features, our model automatically learns features in a hierarchical fashion and predicts saliency map in an end-to-end manner. DeepFix is designed to capture visual semantics at multiple scales while taking global context into account. Generally, fully convolutional nets are spatially invariant which prevents them from modeling location dependent patterns (e.g. centre-bias). Our network overcomes this limitation by incorporating a novel Location Biased Convolutional layer. We experimentally show that our network outperforms other recent approaches by a significant margin. In general, human eye fixations correlate with locations of salient objects in the scene. However, only a handful of approaches have attempted to simultaneously address these related aspects of eye fixations and object saliency. In our work, we also propose a deep convolutional network capable of simultaneously predicting eye fixations and segmenting salient objects in a unified framework. We design the initial network layers, shared between both the tasks, such that they capture the global contextual aspects of saliency, while the deeper layers of the network address task specific aspects. Our network shows a significant improvement over the current state-of-the-art for both eye fixation prediction and salient object segmentation across a number of challenging datasets.

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