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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.
151

Regionalização da assistência hospitalar: estudo do fluxo e demanda na região de Ribeirão Preto-SP, no ano de 2000 / Regionalization of hospital care: a study of flux and demand in the region of Ribeirão Preto – SP, in the year of 2000

Rezende, Carlos Eduardo Menezes de 27 April 2004 (has links)
O Sistema Único de Saúde (SUS) foi configurado tendo como linha mestra de sua organização a descentralização de suas ações, cabendo ao nível central a elaboração e gestão das políticas de saúde. Diante da necessidade de racionalizar recursos, a regionalização se apresenta como meio para implementar uma descentralização que considere a atuação em nível ampliado, além do município, e propicie melhor acesso aos diferentes níveis de complexidade da assistência com melhor aproveitamento de recursos e economia de escala. Organizar um sistema de saúde em nível regional significa a consideração de diferentes variáveis como o fluxo espontâneo de usuários influenciado pelo papel socioeconômico exercido pelos diferentes municípios, o conflito de interesses devido ao direcionamento de recursos, a identificação das necessidades regionais e sua contraposição às propostas dos prestadores e a dificuldade para mensurar a demanda por serviços. Este trabalho estudou o fluxo de internações hospitalares dos sistemas público e supletivo de assistência na região de Ribeirão Preto no intuito de identificar sua distribuição e fatores associados. A origem dos dados foi a Folha de Alta Hospitalar do Centro de Processamento de Dados Hospitalares (CPDH) do Departamento de Medicina Social da Faculdade de Medicina de Ribeirão Preto da Universidade de São Paulo (FMRP–USP), preenchida em todas as altas hospitalares – SUS e não SUS - de todos os hospitais da região que, depois de recolhida e processada eletronicamente, onstitui um banco de dados no referido centro. A análise dos dados foi feita através do gerenciador de banco de dados Epi-Info™ versão 3.2. Os resultados obtidos foram comparados e estudados à luz do Plano Diretor de Regionalização do Estado de São Paulo para a região de Ribeirão Preto –SP. / The Brazilian National Health System (SUS) was established with a basis in decentralized administration. The central level performs the function of producing the policy and coordinates its application into practice. Facing limited resources, the regionalization represents a way to conduct a decentralized system in larger territories than the municipalities. The expectations are to improve access to the different levels of complexity of care avoiding unnecessary expenditure. The regionalization of hospital care implies various variables, as the spontaneous movement of people influenced by socioeconomic factors, the imbalance because of resources, the region’s needs under an epidemiological basis and interests of providers. This work studies the flux of people receiving hospital care in both public (SUS) and private (NSUS) health assistance in the region of Ribeirão Preto, São Paulo State, Brazil. It tries to identify factors which influence the flux and demand distribution. The data came from the Centro de Processamento de Dados Hospitalares (CPDH) do Departamento de Medicina Social da Faculdade de Medicina de Ribeirão Preto da Universidade de São Paulo (FMRP–USP), which registers all hospital discharge in the region. The analysis was done using the software Epi Info™ 3.2 version. The results were compared with the plan for the regionalization in São Paulo State for the region of Ribeirão Preto.
152

Regionalização da assistência hospitalar: estudo do fluxo e demanda na região de Ribeirão Preto-SP, no ano de 2000 / Regionalization of hospital care: a study of flux and demand in the region of Ribeirão Preto – SP, in the year of 2000

Carlos Eduardo Menezes de Rezende 27 April 2004 (has links)
O Sistema Único de Saúde (SUS) foi configurado tendo como linha mestra de sua organização a descentralização de suas ações, cabendo ao nível central a elaboração e gestão das políticas de saúde. Diante da necessidade de racionalizar recursos, a regionalização se apresenta como meio para implementar uma descentralização que considere a atuação em nível ampliado, além do município, e propicie melhor acesso aos diferentes níveis de complexidade da assistência com melhor aproveitamento de recursos e economia de escala. Organizar um sistema de saúde em nível regional significa a consideração de diferentes variáveis como o fluxo espontâneo de usuários influenciado pelo papel socioeconômico exercido pelos diferentes municípios, o conflito de interesses devido ao direcionamento de recursos, a identificação das necessidades regionais e sua contraposição às propostas dos prestadores e a dificuldade para mensurar a demanda por serviços. Este trabalho estudou o fluxo de internações hospitalares dos sistemas público e supletivo de assistência na região de Ribeirão Preto no intuito de identificar sua distribuição e fatores associados. A origem dos dados foi a Folha de Alta Hospitalar do Centro de Processamento de Dados Hospitalares (CPDH) do Departamento de Medicina Social da Faculdade de Medicina de Ribeirão Preto da Universidade de São Paulo (FMRP–USP), preenchida em todas as altas hospitalares – SUS e não SUS - de todos os hospitais da região que, depois de recolhida e processada eletronicamente, onstitui um banco de dados no referido centro. A análise dos dados foi feita através do gerenciador de banco de dados Epi-Info™ versão 3.2. Os resultados obtidos foram comparados e estudados à luz do Plano Diretor de Regionalização do Estado de São Paulo para a região de Ribeirão Preto –SP. / The Brazilian National Health System (SUS) was established with a basis in decentralized administration. The central level performs the function of producing the policy and coordinates its application into practice. Facing limited resources, the regionalization represents a way to conduct a decentralized system in larger territories than the municipalities. The expectations are to improve access to the different levels of complexity of care avoiding unnecessary expenditure. The regionalization of hospital care implies various variables, as the spontaneous movement of people influenced by socioeconomic factors, the imbalance because of resources, the region’s needs under an epidemiological basis and interests of providers. This work studies the flux of people receiving hospital care in both public (SUS) and private (NSUS) health assistance in the region of Ribeirão Preto, São Paulo State, Brazil. It tries to identify factors which influence the flux and demand distribution. The data came from the Centro de Processamento de Dados Hospitalares (CPDH) do Departamento de Medicina Social da Faculdade de Medicina de Ribeirão Preto da Universidade de São Paulo (FMRP–USP), which registers all hospital discharge in the region. The analysis was done using the software Epi Info™ 3.2 version. The results were compared with the plan for the regionalization in São Paulo State for the region of Ribeirão Preto.
153

Measurement of radiation in complex geometries and comparison with calculational techniques

De Almeida, Jose Sergio January 2000 (has links)
During the development of flight tests of a spacecraft, heat exchange occurs among the many physically separated subsystem surfaces through the phenomenon of thermal radiation. Considering the increasing complexity of the geometrical forms and shapes in the design of such systems, the monitoring and control of the radiative heat fluxes taking place in the multi-reflecting, absorbing and emitting heat transfer environment are very critical. Because the analytical solution of thermal radiation in such geometrically complex three-dimensional systems is not practical, extensive numerical modelling techniques are widely used to predict radiative heat fluxes on the many thermally active surfaces. From experience, it is found that this can be very difficult and not at all commensurate with fast feedback unless the analysis is from a simple system layout. Considering that a relatively new approach dedicated to the basic analysis of radiative heat flux has been developed by the heat transfer community as a numerical approximation called the Discrete Ordinates Method (DOM), a first question did arise in terms of how well an enhanced and more comprehensive formulation based on this concept would fulfil the task of achieving faster results whilst still accurately predicting radiative heat transfer in three-dimensional, more complex geometries.
154

Fabrication of tissue equivalent proportional counters, single- and multi-wire types, and their use in 14 MeV neutron dosimetry.

January 1983 (has links)
by Chan Yiu Nam. / Chinese title: / Includes bibliographical references / Thesis (M.Phil.) -- Chinese University of Hong Kong, 1983
155

Conception réalisation et mise en oeuvre d'un scintillomètre : influence de la vapeur d'eau dans la bande 940nm / Designing and making a scintillometer : influence of water vapour in the 940nm band

Solignac, Pierre-Adrien 09 December 2009 (has links)
L'atmosphère et la surface terrestre interagissent en permanence par le biais des échanges d'énergie et de matière. Ces flux jouent un rôle important dans l'étude de l'hydrologie des surfaces ou de l'écologie terrestre, ou bien encore l'étude des phénomènes météorologiques et climatiques. En effet, ils représentent les conditions aux limites des différents compartiments du système Terre et la quantification de ces échanges à différentes échelles spatiales est indispensable pour les modèles de prévision. Les mesures de flux d'énergie sont très répandues pour des mesures très localisées, in situ et au sol. Cependant, peu d'instruments de mesures permettent d'obtenir des flux intégrés sur des distances de l'ordre de la centaine de mètres à quelques kilomètres, c'est-à-dire des distances correspondant à la représentativité des pixels des images satellitaires. On compte parmi eux les scintillomètres, instrument de mesure optique, permettant de calculer les flux intégrés de chaleur sensible à partir des mesures de paramètres caractérisant l'intensité turbulente de l'atmosphère tels que le paramètre de structure de l'indice de réfraction de l'air Cn². La présence de vapeur d'eau dans l'atmosphère peut cependant perturber le signal de ces instruments. L'objectif de ce travail est le développement et la mise en oeuvre d'un scintillomètre optique permettant de mettre en évidence la contribution de l'absorption par la vapeur d'eau sur les scintillations. Les études menées à partir du développement instrumental ne s'orienteront qu'autour de la bande d'absorption à 940nm, longueur d'onde d'émission de certains scintillomètres LAS (Large Aperture Scintillometer). Au début de ma thèse, un prototype de scintillomètre, type LAS, a été conçu de façon à maitriser complètement la technologie : partie optique électronique et le traitement du signal reçu. Celui-ci a ensuite été installé au-dessus d'un site de cultures dans les environs de Toulouse, au cours des années 2007 et 2008. Les résultats obtenus avec ce prototype ont permis d'optimiser le choix de la méthode de calcul H à partir du Cn², en fonction du rapport de Bowen (rapport du flux de chaleur sensible sur le flux de chaleur latente). Les variations de l'intensité lumineuse de l'onde, menant au Cn², sont principalement dues à des effets de réfraction et de dispersion, maissont aussi sensibles à l'absorption de la vapeur d'eau. Afin de quantifier l'influence de 'absorption sur le signal Cn², j'ai utilisé 2 approches : une première approche par filtrage numérique (‘Gabor Transform'), et une seconde, par méthode chromatique. Cette dernière a nécessité de modifier considérablement le système optique du prototype LAS. Les résultats obtenus expérimentalement montrent que la contribution de l'absorption à la mesure du Cn² est en moyenne assez faible, mais qu'elle peut prendre de forte valeur, principalement lors de faibles flux H. La quantification de l'absorption par méthode hromatique est pour l'instant limité au développement technique de l'instrument. / Atmosphere, soil and vegetation are in interactions by the bias of energetic or matter exchanges. This latters have an important impact on hydrology, ecology, meteorology. Actually, they represent the boundary conditions of the Earth-Atmosphere system. Then, the quantification of these exchanges or fluxes is necessary to understand large scales phenomena and to improve forecasting models. Numerous devices are able to quantify these fluxes at local scales, but few are available to measure them over kilometres, which mean at the resolution of remote sensing datas. Amongst them, we can notice the scintillometers that are able to calculate sensible heat fluxes over distances from hundred meters to few kilometres. Actually, these devices are sensitive to variations of the refractive index of air, mainly due to turbulent eddies, defined by the structure parameter of refractive index : Cn². However, this measurement can be altered by the presence of water vapour in the air. Thus, the aim of this work is to design and make a scintillometer which is able to quantify the water vapour contribution on the Cn² measurement. In this thesis, we will focus on this contribution in the 940nm band which is the wavelength of various scintillometers LAS (Large Aperture Scintillometers). At the beginning of my PhD thesis, un scintillometer prototype has been realised in order to master the technology : optics, electronics, signal processing…This latter has been set up over crops at a few kilometres from Toulouse, between 2007 and 2008. Thanks to the results of this scintillometer, we optimize the choice on the Cn² to H algorithm, according to the Bowen ratio ß (ratio of sensible to latent heat flux). Variations of the light beam, leading to the Cn², are mainly due to refraction and dispersion effect. However, absorption can be important. In order to quantify the contribution of absorption on the Cn², 2 methods are suggested : one based on signal processing aspect (Gabor filtering), and the second one on two wavelengths propagation. To realize this latter the optics and electronics of the device have been really modified. Results show that absorption contribution is small, but can be important for low H values. Finally, the quantification of absorption by two wavelengths approach is nowadays bounded to instrumental development.
156

Synthèse d'observateurs à dérivées partielles pour le diagnostic de défauts des systèmes de distribution de flux / PDE observers design for fault diagnosis on distribution flow networks

Idellette Judith, Hermine Som 30 March 2017 (has links)
Les réseaux de distribution de flux sont modélisés par des systèmes hyperboliques linéaires ou non linéaires de lois de conservation avec terme source. La surveillance de ces réseaux (diagnostic de défauts) nécessite la connaissance de certaines variables d’état. Or dans la plupart des cas, il n’est pas possible de mesurer toutes les variables d’états et des observateurs basés sur le système d’équations aux dérivées partielles représentant le réseau peuvent alors être utilisés. Dans cette thèse, l’observabilités des systèmes hyperboliques est tout d’abord étudiée puis les observateurs classiques et robustes à dérivées partielles, avec injection de l’erreur d’estimation aux frontières ou dans la dynamique du système sont proposés. Ces observateurs fournissent des estimations en ligne des signaux qui ne sont pas mesurés. Ces estimations seront utilisées pour le diagnostic des systèmes de distribution de flux. Les performances des observateurs et l’approche de diagnostic sont validées sur le système de distribution d’eau d’un bâtiment de l’Université de Lille 1 Sciences et Technologies, dans le cadre du projet SUNRISE SMART CITY. Des données réelles, prélevées sur le site en absence et en présence de fuites sont utilisées. / Distribution flow networks are modeled by linear or nonlinear systems of balance laws. The monitoring of these networks (Faults detection and isolation) requires knowledge of certain state variables. However, in most cases it is not possible to measure all the state variables. Observers based on the partial differential equations which modelize the network dynamic can be used to provide state estimates. In this dissertation, the observability of the hyperbolic systems is first studied and then classical and robust PDE observers with injection of the state estimation error at boundaries or in the system dynamics are proposed. These observers provide on-line estimation of signals that are not measured. The estimation is used for the diagnosis of distribution flow systems. The performance of the observers and the diagnosis approach are validated on real flow data collected from the water distribution system (WDS) of Polytech’Lille (Cité scientifique, University of Lille 1 Sciences and Technologies), within the framework of the SUNRISESMART CITY Project. Data which are taken from the WDS in the absence and in the presence ofleakeage are used.
157

Temporal Sodium Flux In A Woodlot Soil Irrigated With Secondary Treated Effluent: The Implications For Sustainable Irrigation And Soil Management

Lucas, Steven Andrew January 2007 (has links)
This study reports results obtained and the approach taken in investigating the temporal sodium flux in a woodlot soil receiving secondary treated effluent at Branxton, NSW. Previous research has shown woodlot soils receiving secondary treated effluent undergo an increase in exchangeable sodium percentage (ESP) over time. Increased soil ESP influences micro-aggregate/soil pore stability and, particularly when subject to irrigation waters of specific low-electrolyte concentrations, results in decreased soil permeability and a subsequent need to reduce effluent application rates. Therefore, in irrigated woodlot soils it has been necessary to implement strategies to remove excess sodium from the root zone to maintain optimum permeability of the receiving soil, that is, maintaining the cation balance (as soil ESP) to promote optimum soil pore size. To maintain optimum permeability, an understanding is needed of temporal variations in the accumulation/leaching (flux) of sodium within a soil under secondary treated effluent irrigated conditions. The ability to define the sodium flux depends on the frequency of soil sampling and the ability to interpret the net loss/gain in soil sodium in relation to the applied hydraulic load over time. Past research has measured changes in soil ESP on an annual basis, or longer, making it impossible to interpret temporal sodium flux within a given year. The rate of change of soil ESP has ramifications for optimum permeability within an effluent irrigated woodlot. With respect to increasing/decreasing soil ESP, a major response of the clay particles within micro-aggregates is the deformation of conducting soil pores and reduced hydraulic conductivities. In addition, clay dispersion is governed by the soil ESP and electrolyte concentration of the infiltrating waters at the time, where dispersed clay particles may block conducting soil pores and further reduce hydraulic conductivity. Therefore, investigating the temporal sodium flux in conjunction with the temporal variation in electrolyte concentration of infiltrating waters will give greater insight into the response of effluent irrigated soils to sodium-rich waters over time. Three research aims were formed to investigate temporal sodium flux. These include: 1. To investigate trends in the dominant water balance components for a woodlot soil receiving secondary treated effluent (STE); 2. To examine temporal and spatial variation in both the water balance components and measured soil properties, particularly the sodium flux; and 3. To investigate the implications of the sodium flux on the loss of soil structure and drainage over time (dispersion events), particularly in relation to temporal changes in soil ESP and effluent SAR. Monitoring programs for water balance components and soil parameters covered the period January 2002 – October 2003. Every two months, soil samples were taken at designated sites and at different depths (10, 20, 40, 60, and 80 cm). These samples were analysed for exchangeable cations (Ca2+, Mg2+, Na+ and K+), from which the ESP values were derived. Also, this appears to be the first time that soil sampling at this frequency, which enables the temporal sodium flux to be determined, has been carried out. Column leaching experiments were also performed over the study period to illustrate the response of the woodlot soil, in terms of micro-aggregate stability, to hydraulic loads of varying SAR. Column leaching experiments also confirmed the rate of solute movement through the soil profile and the woodlot soil’s ability to bind/exchange sodium under different hydraulic loads and electrolyte concentrations. Soil extraction plate methods were used to determine wilting point and field capacity for these soils. The Sodium Adsorption Ratio (SAR), which is the solutional equivalent to soil ESP, was used to define the electrolyte concentration of the applied effluent and rainfall to the woodlot. The net loss/gain of exchangeable sodium at different depths and times was determined and compared with changes in water balance components and the measured volumetric soil water over time. The soil water surplus/deficit was recorded at a daily time-step and a cumulative approach was used to determine the long-term soil water surplus/deficit. In addition, variations in groundwater levels were monitored to observe if surplus irrigation events were reflected in temporal trends. As a result of determining the temporal variation in soil ESP, effluent and rainfall SAR, daily soil water deficit/surplus (short-term), cumulative soil water deficit/surplus (long-term) and volumetric soil moisture, temporal trends are presented. The sodium flux was then investigated by interpreting trends in the monitored data with respect to the dominant water balance components. All parameters were then used to model the potential dispersive behaviour of the receiving soil over time and depth, in relation to the volume and electrolyte concentration of the effluent and rainfall applied over time. The implications for soil structure and permeability depend on variations in soil ESP and effluent SAR. Results from this research show that soil ESP varied by as much as 24% over a four-month period and is shown to be a function of the sodium loading (from STE) and soil water surplus/deficit. On each sampling occasion, soil ESP generally increased with depth at all irrigated sites. Soil ESP at non-irrigated sites was much lower than irrigated sites, although the variability in soil ESP was much greater. Variations in SAR of the waters received by the woodlot soil (effluent and rainfall) over the study period ranged from 0.5 to 5.9. It is shown that the SAR range, coupled with variations in soil ESP, has ramifications for maintaining long-term soil structure. Soil structure at different sites within a woodlot will respond differently according to the soil ESP/effluent SAR relationship. The dispersive potential of soil at a given ESP receiving irrigation waters of known SAR was assessed in light of the relationship between soil ESP and effluent SAR. This showed the dynamic response of effluent irrigated soils to the long-term temporal variation in electrolyte concentration of rainfall/effluent. The relationship between soil ESP and effluent SAR is graphically presented as a continuum, which in turn can be used as a management tool for assessing the potential for dispersion of clay particles in a soil of known ESP and irrigated with waters of known SAR. By identifying trends in the temporal sodium flux, the optimum permeability of the receiving soil can be assessed in relation to the electrolyte concentration of the applied waters and the soil exchangeable sodium percentage (ESP). Secondary treated effluent application rates can then be corrected to prevent “dispersive” irrigation events over the long term and/or management strategies applied to remove excess sodium from the soil profile. The significance of the research is that a better understanding of the temporal dynamics of sodium in the soil profile will allow improved management of effluent irrigated woodlots, with the aim of making the practice sustainable with respect to controlling accumulating soil sodium and maintaining soil structure for future landuse. / PhD Doctorate
158

Typage du flux d'information sûr: déclassification et mobilité

Matos, Ana Almeida 01 1900 (has links) (PDF)
Nous nous intéressons au sujet de la confidentialité et de la déclassification. Nous étudions en particulier l'usage d'un système de types et d'effets pour assurer de manière statique des politiques de sécurité flexibles pour un langage d'ordre supérieur impératif avec concurrence. Une méthodologie générale pour définir et prouver la correction du système de types et d'effets pour de telles propriétés est présentée. Nous considérons deux points principaux : - La question de trouver un mécanisme flexible de contrôle d'information qui permet la déclassification. Notre mécanisme de déclassification prend la forme d'une déclaration de politique locale de flux qui implémente une politique locale de flux d'information. - La question jusqu'ici inexplorée de contrôler les flux d'information dans un environnement global. Notre modèle de réseau, qui généralise l'environnement global, inclut une notion de domaine et une primitive de migration standard pour le code et les ressources. De nouvelles formes de perte d'information, introduites par la mobilité du code, sont révélées. Dans les deux cas mentionnés ci-dessus, pour prendre en compte les politiques de flux globales nous introduisons des généralisations de la non-interférence, qui sont nommées non-divulgation et non-divulgation pour les réseaux. Ces généralisations sont obtenues `a l'aide d'une représentation concrète des treillis de sécurité, où les nivaux de confidentialité sont des ensembles de principaux, semblables `a des listes de contrôle d'accès.
159

Large-eddy simulation of the effects of debris on tornado dynamics

Gong, Baiyun. January 1900 (has links)
Thesis (Ph. D.)--West Virginia University, 2006. / Title from document title page. Document formatted into pages; contains xxiv, 163 p. : ill. (some col.). + QuickTime and media files. Includes video files in the mpeg and wmv formats. Vita. Includes abstract. Includes bibliographical references (p. 126-136).
160

Development of an ammonia emission protocol and preliminary emission factor for a central Texas dairy

Rose, Adam Joseph 30 September 2004 (has links)
A protocol was developed to measure ammonia emission concentrations from dairies using an isolation flux chamber. A hybrid dairy in Comanche county, Texas, was measured for one week each during August 2002 and January 2003. Sixty total ammonia samples were taken from the free stall barn, open lot, mixing tank, separated solids, compost, and two lagoons using the developed protocol. The ammonia concentration measurements were made using a chemiluminescence analyzer located inside a mobile laboratory. From the emission concentrations recorded, it was estimated that 9.68 metric tons of ammonia were produced from this dairy per year. An emission factor of 13.34 ± 28.80 kilograms per day per thousand head of cattle (kg/day/1000 head) was estimated for this dairy (±95% confidence intervals) during summer conditions. For winter conditions the emission factor was 12.05 ± 12.89 kg/day/1000 head. The 11% difference of the emission factors from summer to winter conditions was predominantly from the change in ambient and control volume temperatures (a mean difference of approximately 25 degrees Celsius), differences in source temperatures, and seasonal variability in husbandry. The adsorption of ammonia onto different polymer tubing used in pollutant stream conveyance was researched for possible systematic losses. Teflon and low density polyethylene (LDPE) were tested for ammonia losses with treatments of: temperature, length, and inlet concentration. Inlet concentration and temperature were significant factors used to describe ammonia adsorption for Teflon, whereas LDPE was also affected by tubing length. These factors were used to create a model to correct the summer dairy measurements for ammonia losses, resulting in an emission factor increase of 8.3% over the original value obtained from the flux chamber. A nitrogen mass balance was performed to estimate the amount of nitrogen available for ammonia formation as excreted - 177.5 kilograms per year per animal (wet basis). The amount of ammonia excreted per year was also estimated to be 26.63 kilograms per year. The measured ammonia emitted from the dairy was five times less than the ammonia excreted and thirty-six times less than the total nitrogen excreted.

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