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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.
21

Role of gonadal steroids in the mating behaviour of the ram Ovis aries L. /

D'Occhio, Michael J. January 1983 (has links) (PDF)
Thesis (Ph.D.)-- University of Adelaide, Dept. of Animal Sciences,1983. / Typescript (photocopy). Includes bibliographical references (leaves 198-259).
22

CaracterizaÃÃo da MicrofÃsica das Nuvens sobre a AmazÃnia Brasileira em RegiÃes de Pasto e Floresta Medida em Situ por AviÃo Instrumentado e sua AplicaÃÃo Direta no Modelo Regional Rams

AntÃnio Carlos Santana dos Santos 22 July 2005 (has links)
nÃo hà / Conhecer a microfÃsica de nuvens à fundamental para o entendimento da dinÃmica, bem como a sua aplicaÃÃo direta em modelos regionais de tempo e clima. O trabalho proposto nesta tese tem o objetivo de verificar o comportamento dinÃmico e microfÃsico de nuvens amazÃnicas e, em particular, comparar esse comportamento para nuvens sobre as regiÃes de pasto e floresta no Estado de RondÃnia. Diversas medidas termodinÃmicas e microfisicas obtidas in situ com o aviÃo laboratÃrio Citation II foram analisadas, sendo possÃvel extrair algumas conclusÃes relativas ao comportamento microfÃsico das nuvens formadas sobre pasto e floresta. TambÃm foram feitas diversas simulaÃÃes com o modelo RAMS (Regional Atmospheric Model System): testes de sensibilidade em relaÃÃo à cobertura vegetal (pasto ou floresta), que nÃo apresentaram diferenÃas significativas no perfil vertical da microfÃsica das nuvens; simulaÃÃes feitas inicializando o modelo com o diÃmetro mÃdio ou com a concentraÃÃo de gotÃculas, cujos resultados apresentaram diferenÃas significativas. Os resultados obtidos nas simulaÃÃes inicializadas com a concentraÃÃo de partÃculas mostraram-se bastante prÃximos daqueles observados durante o experimento ABRACOS (Anglo-Brazilian Amazonian Climate Observation Study). / Improving or knowledge on cloud microphysics is fundamental to understand the clouds dynamics, its role in the atmospheric general circulation and energy balance, as well as in weather and climate prediction applications using large-scale and mesoscale models. This work aims to verify the dynamic and microphysical behavior of clouds over the Amazon basin and, in particular, to compare those behaviors over pasture and forest areas in RondÃnia State. Several thermodynamic and microphysics measurements obtained in situ with the University of North Dakota instrumented aircraft (Citation II) were analyzed, allowing us to reach some conclusions about the microphysical and dynamical characteristics of clouds over pasture and forest areas. Cloud-resolving simulations using RAMS model (Regional Atmospheric Model System) were performed in order to assess sensitivities regarding vegetation cover (pasture or forest). The simulations did not show significant differences in the average vertical profiles of cloud microphysics variables (such as mixing rations for the different hydrometeor species). On the other hand, simulations using different model setups (changes in initialization or average diameter or droplets concentration), produced significant differences in precipitation and hydrometeor concentration, per exempe. Finally, simulations in which the droplets concentrations were specified showed better agreement with observations obtained during ABRACOS experiment (Anglo-Brazilian Amazonian Climate Observation Study), than simulations in which average diameter were specified.
23

Ram performance testing programs in Virginia

Lester, Donya C. January 1983 (has links)
Prices paid for yearling rams were influenced (P < .001) by TSC, BT, YW and FW. The importance of YW increased with time, while the role of TSC declined in later time periods, suggesting that buyers were willing to pay more for superior performance and less for subjective conformation and type in later years than when the test began. A larger ram with an equivalent performance record was worth more than a smaller ram. The relative importance of FW and YW in defining price changed. In early years superiority in both traits was worth approximately the same, while in later years a higher YW brought about 2 1/2 times the premium of the same increase in FW. Prices paid for ram lambs were affected by TSC, BT, DG and FW, but the time period involved was too short to draw conclusions concerning changes in their relative importance. Phenotypic trends for yearling rams' WW, FW, YW and DG were positive (P < .001), and rates of increase were different for breeds (P < . 001). The decrease in mean age of tested rams and the increase in DG contributed to a quadratic trend in YW and supported adjustment of the data for age. Environmental trends, analyzed by a within-sire analysis of 1885 progeny of 4:30 sires, were not significant. Estimated genetic gains due to sires were: 1.06 ± .30 kg/yr for FW, 1.16 ± .32 kg/yr for YW, .36 ± .18 kg/yr for WW and .0037 ± .0021 kg/d/yr for DG. Phenotypic trends for the ram lambs were: .906 ± .198 kg/yr for FW, .00956 ± .000880 for WDA and .00212 ± .00228 kg/d/yr for DG. Yearling rams' OW and FW were correlated (P < .001), as were the same traits for ram lambs. The yearling correlation was much lower than that of the lambs, however (r = .89 vs r = .66). The correlation (P < .001) of OW and DG was .22 and -.20 for yearlings and ram lambs, respectively. Age and DG were correlated (P < .001) with a coefficient of -.20 for both yearlings and ram lambs. Yearling rams' SHT, HHT and BLGTH were highly correlated ( P < . 001), and cannon length was moderately correlated (P < .005) to SHT and HHT. Suffolks were taller than Hampshires and Dorsets. All three breeds made similar gains in SHT within the same year. SC generally increased over the course of the test. The SC of the black-faced breeds sometimes regressed from April to May, but showed gains from 0 to 2.15 ± .24 cm for the overall measurement interval. Dorset SC always increased the most with gains ranging from 2.08 ± .93 cm to 3. 88 ± 1.10 cm. Suffolk ram lambs were tallest in the first 2 yr and were similar to Hampshires in the third. Gains in ram lamb SHT over short intervals were negated by the shearing which took place before the second measurement. Mean gains over the lengthened 1982 test period ranged from 6. 04 ± .68 cm for Hampshires to 7.37 ± .36 for Suffolks. SHT was correlated ( P < .001) with weight, generally moderately correlated (P < .05) with DG and not usually correlated with age. Only the Suffolk lamb SC consistently increased from July to August. The SC of all breeds increased from May to August, Suffolks by the greatest amount. SC was correlated (P < .05) with SHT and generally was correlated (P < .005) with weight. Only the final SC was correlated ( P < . 005) with DG, and SC and age were not usually correlated. / M.S.
24

"Circulações locais em São Paulo e sua influência sobre a dispersão de poluentes" / Local Circulations in São Paulo and its Influence on Pollution Dispersion

Freitas, Edmilson Dias de 29 April 2003 (has links)
Os efeitos causados pela presença de áreas urbanizadas da Região Metropolitana de São Paulo (RMSP), conhecidos por ilha de calor urbana, são estudados através da modelagem numérica e da análise de alguns dados observacionais, coletados no período de inverno de 1999 durante a 1ª Fase intensiva de medidas de campo do Projeto Temático FAPESP “Meteorologia e Poluição do Ar em São Paulo" e da rede automática da CETESB. Através da utilização de imagens do satélite LANDSAT-5, foi obtido um arquivo de ocupação do solo na RMSP numa resolução de aproximadamente 424 m. Foram definidos dois tipos de ocupação urbana que diferem principalmente na verticalização e espaçamento entre as construções. Simulações realizadas com uma parametrização adequada ao tratamento das propriedades da superfície em áreas urbanas, o modelo RAMS-TEB, mostraram que as fontes antropogênicas de calor de origem veicular são de grande importância no ciclo diurno de temperatura e umidade na RMSP. Uma comparação entre os dados simulados pelo modelo e dados observacionais de superfície apresentou coeficientes de correlações superiores a 0,9 para a temperatura e superiores a 0,8 para a umidade relativa. A interação entre a brisa marítima e a ilha de calor intensifica as zonas de convergência no centro da cidade, podendo ocasionar a re-circulação de poluentes nessa região. Simulações sobre o efeito da urbanização mostram que a ilha de calor urbana faz com que haja uma propagação mais rápida da frente de brisa até o centro da RMSP, que permanece estacionária por algum tempo nessa região. Os efeitos da topografia mostraram-se fundamentais na intensidade da brisa marítima e sua propagação sobre o continente. A presença de grandes corpos d’água, tais como a represa de Guarapiranga e Billings, contribui para a diminuição das amplitudes do ciclo diurno de temperatura na RMSP através das circulações do tipo brisa lacustre geradas pelos mesmos. O uso de um modelo de dispersão mostrou que, com a propagação da frente de brisa para o interior (na direção SE-NW), poluentes emitidos na RMSP são transportados para áreas remotas, diminuindo a concentração dos mesmos nas regiões emissoras. / The effects caused by urbanization in the Metropolitan Area of São Paulo (MASP), known as urban heat island, are studied through the use of numerical modeling and some observed data, collected in the 1999’s winter time during the first phase of intensive field measurements from the Thematic Project FAPESP “Meteorology and Air Pollution in São Paulo" and also from CETESB automatic network. A 424 m resolution land use file was created using LANDSAT-5 satellite pictures where two different kinds of urban regions were identified. The main differences between these regions are the vertical structure and spacing between buildings. Simulations performed with an appropriate parameterization for the treatment of surface properties in urban areas showed that anthropogenic sources due to traffic are of great importance to the temperature and humidity diurnal cycle in MASP. Comparisons between simulated and observed surface data had a correlation coefficient greater than 0.9 for temperature and greater than 0.8 for relative humidity. The interaction between the see breeze and the urban heat island intensify the convergence zones in the center of the city, eventually causing the re-circulation of pollutants in this region. Simulations of the urbanization effects showed that the urban heat island is responsible for a faster propagation of the sea breeze front up to the center of the MASP, remaining stationary in this region for some time. The topographic effects are fundamental in the intensity of the sea breeze and its inland propagation. The presence of large water bodies, as the Guarapiranga and Billings Dams, contribute to a decrease in the temperature diurnal cycle amplitudes because of the lake breeze circulations generated by them. The use of a simple dispersion model showed that with the propagation of the sea breeze front to the countryside (in the direction SE-NW), pollutants emitted in MASP are transported to remote areas, causing a decrease in the concentration of these pollutants in the source region.
25

"Circulações locais em São Paulo e sua influência sobre a dispersão de poluentes" / Local Circulations in São Paulo and its Influence on Pollution Dispersion

Edmilson Dias de Freitas 29 April 2003 (has links)
Os efeitos causados pela presença de áreas urbanizadas da Região Metropolitana de São Paulo (RMSP), conhecidos por ilha de calor urbana, são estudados através da modelagem numérica e da análise de alguns dados observacionais, coletados no período de inverno de 1999 durante a 1ª Fase intensiva de medidas de campo do Projeto Temático FAPESP “Meteorologia e Poluição do Ar em São Paulo” e da rede automática da CETESB. Através da utilização de imagens do satélite LANDSAT-5, foi obtido um arquivo de ocupação do solo na RMSP numa resolução de aproximadamente 424 m. Foram definidos dois tipos de ocupação urbana que diferem principalmente na verticalização e espaçamento entre as construções. Simulações realizadas com uma parametrização adequada ao tratamento das propriedades da superfície em áreas urbanas, o modelo RAMS-TEB, mostraram que as fontes antropogênicas de calor de origem veicular são de grande importância no ciclo diurno de temperatura e umidade na RMSP. Uma comparação entre os dados simulados pelo modelo e dados observacionais de superfície apresentou coeficientes de correlações superiores a 0,9 para a temperatura e superiores a 0,8 para a umidade relativa. A interação entre a brisa marítima e a ilha de calor intensifica as zonas de convergência no centro da cidade, podendo ocasionar a re-circulação de poluentes nessa região. Simulações sobre o efeito da urbanização mostram que a ilha de calor urbana faz com que haja uma propagação mais rápida da frente de brisa até o centro da RMSP, que permanece estacionária por algum tempo nessa região. Os efeitos da topografia mostraram-se fundamentais na intensidade da brisa marítima e sua propagação sobre o continente. A presença de grandes corpos d’água, tais como a represa de Guarapiranga e Billings, contribui para a diminuição das amplitudes do ciclo diurno de temperatura na RMSP através das circulações do tipo brisa lacustre geradas pelos mesmos. O uso de um modelo de dispersão mostrou que, com a propagação da frente de brisa para o interior (na direção SE-NW), poluentes emitidos na RMSP são transportados para áreas remotas, diminuindo a concentração dos mesmos nas regiões emissoras. / The effects caused by urbanization in the Metropolitan Area of São Paulo (MASP), known as urban heat island, are studied through the use of numerical modeling and some observed data, collected in the 1999’s winter time during the first phase of intensive field measurements from the Thematic Project FAPESP “Meteorology and Air Pollution in São Paulo” and also from CETESB automatic network. A 424 m resolution land use file was created using LANDSAT-5 satellite pictures where two different kinds of urban regions were identified. The main differences between these regions are the vertical structure and spacing between buildings. Simulations performed with an appropriate parameterization for the treatment of surface properties in urban areas showed that anthropogenic sources due to traffic are of great importance to the temperature and humidity diurnal cycle in MASP. Comparisons between simulated and observed surface data had a correlation coefficient greater than 0.9 for temperature and greater than 0.8 for relative humidity. The interaction between the see breeze and the urban heat island intensify the convergence zones in the center of the city, eventually causing the re-circulation of pollutants in this region. Simulations of the urbanization effects showed that the urban heat island is responsible for a faster propagation of the sea breeze front up to the center of the MASP, remaining stationary in this region for some time. The topographic effects are fundamental in the intensity of the sea breeze and its inland propagation. The presence of large water bodies, as the Guarapiranga and Billings Dams, contribute to a decrease in the temperature diurnal cycle amplitudes because of the lake breeze circulations generated by them. The use of a simple dispersion model showed that with the propagation of the sea breeze front to the countryside (in the direction SE-NW), pollutants emitted in MASP are transported to remote areas, causing a decrease in the concentration of these pollutants in the source region.
26

Study of an anti-GnRF vaccine as a more welfare friendly method of castration for ram lambs

Masłowska, Katarzyna January 2017 (has links)
Castration of male lambs is performed in all major sheep producing counties as a standard management practice. The reasons to castrate may be different and will depend on the size and type of the farm. Castration gives more control over genetics of the flock, stops inbreeding, unwanted pregnancies and behaviours. It also gives improved carcass characteristics. However, it has been shown that castration is painful and distressing to the animals. Different techniques are used to castrate sheep at the present time such as rubber ring, Burdizzo, combined, short scrotum, and surgical castration. Due to changing attitudes towards animal pain and unnecessary suffering there is a need for further development and implementation of new castration methods, efficient pain assessment techniques, animal welfare codes of practice and legislative requirements to improve lamb well-being. Recent increase of public concern regarding animal welfare is putting pressure on many government bodies to strengthen research in this area and increase attempts to regulate by law unnecessary suffering during standard livestock management practices. Immunocastration with an anti-GnRF vaccine has the potential to be an alternative to common physical castration methods. Nonetheless there is little or no information about the impact of vaccination against GnRF on the physiology of lambs (rams’ reproductive tract, endocrine regulation), emotionality (possible changes to normal behavioural patterns like increased aggression, anxiety) and health (is the vaccine safe to be used and if there are any adverse effects of vaccination like tissue damage, swelling, lesions etc.). There is also little or no information on how the vaccine affects sheep at the time of injection. This study investigates three main questions: Is Immunocastration a pain free alternative to traditional physical methods of castration? Is Immunocastration safe and practical to use? Does Immunocastration influence the male reproductive system in a way to achieve sterility without any negative impact on the ram natural behaviours, wellbeing and health?
27

Análise RAMS de uma família de equipamentos de produção de semicondutores

Oliveira, Mário Joaquim Machado January 2003 (has links)
Dissertação apresentada para obtenção do grau de Mestre, na Faculdade de Engenharia da Universidade do Porto, sob a orientação do Professor Doutor Luís Andrade Ferreira
28

Role of gonadal steroids in the mating behaviour of the ram Ovis aries L.

D'Occhio, Michael J. January 1982 (has links) (PDF)
Typescript (photocopy) Includes bibliographical references (leaves 198-259) The role of gonadal steroids in the mating behaviour of rams was investigated in both entire rams and castrated rams (wethers) treated with different steroids.
29

Observation et modélisation spatiale de la température dans les terroirs viticoles du Val de Loire dans le contexte du changement climatique

Bonnefoy, Cyril 12 April 2013 (has links) (PDF)
Dans un contexte de changement climatique, les impacts attendus sur les terroirs viticoles posent un certain nombre de questions, notamment sur les risques encourus (variation des caractéristiques et de la qualité du vin) et les enjeux. Ce travail de thèse vise à mettre en place une méthodologie de mesures et de modélisation spatiale de la température, dans les terroirs viticoles du Val de Loire, afin de définir le climat actuel et d'apporter des réponses aux conséquences futures du changement climatique à l'aide de simulations adaptées. Une étude diagnostic des données de températures régionales a préalablement été effectuée et montre une augmentation généralisée de la température et des indices bioclimatiques de la vigne depuis 1950. Des expérimentations à échelles locales ont été réalisées dans les terroirs viticoles de la moyenne vallée de la Loire grâce à un important dispositif de mesures climatiques. La variabilité spatiale de la température est notamment mise en évidence par l'étude d'indices bioclimatiques comme les degrés-jours qui montrent des différences parfois comparables à celles observées à l'échelle régionale. Une modélisation multicritères a été appliquée sur un site expérimental des Coteaux du Layon et montre l'importance des facteurs topographiques dans la variabilité de la température. Une dernière étape a permis d'obtenir des simulations du modèle méso-échelle RAMS. Les simulations à 5 km de résolution sur la période de référence 1991-2000 ont été contrôlées sur certains mois clés de la croissance de la vigne puis confrontées aux sorties du modèle ARPEGE-Climat (50 km). Les résultats montrent l'intérêt de la désagrégation d'échelle par le modèle RAMS avec des biais réduits sur les températures, et notamment une meilleure appréhension des extrêmes thermiques. Les simulations de la période future 2041-2050 (Scénario A2) montrent un recul de l'aléa gélif pour le mois d'avril mais une augmentation de la fréquence des journées chaudes (>30°) et très chaudes (>35°C) pendant la période véraison-maturation. Enfin, les simulations de quelques épisodes extrêmes à 200 mètres de résolution ont soulevé toute la complexité de ce type de modélisation, avec des températures plus ou moins bien reproduites selon les journées.
30

Proactive Emergency Preparedness in the Barents Sea

Basharat, Salma January 2012 (has links)
Today rise in oil and gas demand, energy crisis, issues concerning energy security and increase in oil prices in the world provoke further exploration and production of oil and gas. The Arctic Sea is the last frontier of abundant hydrocarbon reserves. Having effective regulations, innovative technologies and adequate safety norms, the world has still seen some major accidents such as Gulf of Mexico accident. Knowing that offshore petroleum industry is moving further north in Arctic poses additional challenges due to harsh climatic conditions and remoteness from existing oil and gas infrastructure. The objective of this thesis is to provide an overview of offshore petroleum activity in arctic and sub-arctic areas as well as the accidents which took place in these areas. Furthermore, the accidents are analyzed with respect to the emergency preparedness handling of accidents using the NORSOK Z-013 standard as one basis. The thesis also discusses the anticipated emergency preparedness challenges for arctic and sub-arctic areas. The Arctic Sea is the final destination in the north having enormous amount of hydrocarbons. The harsh weather conditions of the Arctic Sea characterized by polar lows, long nights, extreme fog and sub-zero temperatures have not prevented the countries bordering the Arctic Sea in exploiting the oil and gas resources. Russia, having extended pipeline infrastructure, has the most active part in the Arctic region followed by the US and Norway. The offshore exploration and production activities in the Canadian and Greenland Arctic Sea are gradually progressing. Up to date, there have been very few accidents in the Arctic Sea thereby providing a limited knowledge base for emergency response in the Arctic Sea. The accidents which we have been able to account for are mainly related to blowout, pipeline leak, ship collision and capsize accidents. The accidents have occurred in the Russian Arctic Sea and the Alaskan Arctic Sea.The NORSOK Z-013 standard refers to alert, danger limitation, rescue, evacuation, and normalization as the five emergency preparedness phases and their detailed description is available in the Activities Regulation by the Petroleum Safety Authority in Norway (PSAN). It is stated in the NORSOK Z-013 standard that a set of Defined Situation of Hazard and Accident (DSHA) needs to be defined as part of the risk and emergency preparedness analysis. The set of DSHAs provided in the &#147;Trends in risk level&#148; project is used in this thesis for the classification and analysis of the accidents in the Arctic Sea.The analysis of the accidents in the Arctic Sea shows that all the emergency operations went through the phases of alert and normalization while the oil spill related accidents did not pass through escape and evacuate operations as there were no personnel involved in these accidents. All the emergency operations were affected by bad and tough weather conditions. Advanced emergency preparedness tools, equipment and technology are needed for effective emergency operations under such conditions. Due to scarcity of accidents in the Arctic Sea, only four DSHAs (out of 12) have been experienced, or at least reported. It may be that some of the remaining DSHAs are not reported due to minor consequences. In addition to the lessons learned from the emergency response operations for the accidents experienced in the Arctic Sea, there are also some emergency preparedness challenges which can be anticipated. The challenging weather conditions due to sudden polar lows, strong winds, spray icing, snowstorms and severe fog can hamper the emergency operations. Furthermore, long distances and lack of infrastructure can create communication and logistic problems and can result in delay of rescue and evacuation operations. Robust and reliable ice and weather data is a challenge due to global warming and may become a limiting factor for the adequate design of offshore equipment. The use and maintenance of emergency response equipment is also a challenge in sometimes dark, snowy and foggy areas of the Arctic Sea and the Barents Sea.

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