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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

Fertility associated antigen in peripubertal beef bulls as an indicator of potential fertility

Gallino, Joanna Lynn 01 November 2005 (has links)
Ejaculates from peripubertal Angus (n=106), Brahman (n=156) and Brangus (n=212) bulls were evaluated for the presence of a 31 kDa protein known as fertility associated antigen (FAA) using the ReproTest for Bulls (ReproTech, Tucson, AZ). This study was designed to test the repeatability of FAA detection using the chute-side cassette and to quantify the relationship of age, scrotal circumference, sperm motility, ejaculate volume and sperm concentration with the presence of FAA in ejaculates from peripubertal bulls. A total of 776 ejaculates were collected, and 77% (n=598) were classified as FAA+. Three ejaculates were obtained from 133 bulls (Angus, n=33; Brahman, n=100) on d 0, 30 and 60. Brahman bulls were older (p<0.0001) at puberty than Angus bulls. Ejaculate volume was the only trait that differed between bulls that were classified as FAA+ and FAA? at first collection. Mean ejaculate volume was greater (p<0.0001) for FAA? than for FAA+ ejaculates. Serial ejaculates were profiled according to one of four FAA classification patterns (0 = three FAA? ejaculates; 1 = three FAA+ ejaculates; 2 = first ejaculate FAA?; and 3 = first ejaculate FAA+). A majority of the bulls were FAA+ on all three ejaculates (57%) or at least on the first ejaculate (25%). Seven bulls (5%) were consistently FAA?, while the remaining bulls (12%) were FAA? on the first ejaculate. There were no differences in scrotal circumference or sperm concentration among FAA profiles. FAA profile-3 bulls were older (p<0.05) than FAA profile-1 bulls at 2nd collection. Sperm motility was greater (p<0.05) for FAA profile-1 than for FAA profile-3 bulls at 1st collection. Ejaculate volume was greater (p<0.05) in FAA profile-0 Angus bulls than for FAA profile-1 at 1st collection and in FAA profile-0 Brahman bulls than FAA profile-2 at 2nd collection. These data indicate that FAA classification was not affected by sperm motility, sperm concentration or scrotal circumference in peripubertal bulls. Repeatability of FAA classification was higher for bulls that were FAA+ at first ejaculation. Thus, peripubertal FAA? bulls should be re-evaluated to increase FAA-classification accuracy for identification of higher fertility as well as lower fertility animals prior to breeding.
2

Análise dos padrões e recomendações da ICAO e da FAA para o projeto geométrico de aeródromos. / Analysis of ICAO and FAA standards and recommendations for aerodrome geometric design.

Silva, Evandro José da 22 March 2012 (has links)
Esta pesquisa de mestrado aborda o projeto geométrico de aeródromos a partir dos padrões e recomendações da ICAO (International Civil Aviation Organization) e da FAA (Federal Aviation Administration). Os padrões e recomendações da ICAO foram extraídos do documento Annex 14 to the Convention on International Civil Aviation e de documentos por ele referenciados. Para o caso da FAA, serviu de base o documento Airport Design: Advisory Circular 150/5300-13, incluindo-se aqueles nele referenciados e considerados pertinentes ao escopo do estudo. Seguindo-se uma estrutura de critérios de projeto proposta, os padrões e recomendações da ICAO e da FAA são comparados entre si, explicitando-se as diferenças nas especificações em si e também na forma como estas especificações são feitas por cada norma. Para o caso em que comparações diretas não são possíveis, as comparações são feitas a partir de um conjunto de aeronaves com características conhecidas. No caso dos critérios cuja avaliação é mais complexa, equacionamentos matemáticos são propostos. Apresenta-se também uma série de flexibilizações dos padrões, as quais são voltadas à acomodação das aeronaves A380-800 e B747-8 em aeroportos existentes. Estas flexibilizações provêm das conclusões do A380 Airport Compatibility Group (AACG) e do Boeing 747-8 Airport Compatibility Group (BACG), no caso dos padrões da ICAO. Para a as flexibilizações dos padrões da FAA, servem de base os Engineering Briefs (EBs) por ela emitidos. Finalmente, com base nos critérios de projeto considerados, é feita uma análise do Aeroporto Internacional de São Paulo/Guarulhos quanto à operação das aeronaves A380-800 e B747-8. / This Master Thesis tackles aerodrome geometric design according to the standards and recommended practices from the ICAO (International Civil Aviation Organization) and the FAA (Federal Aviation Administration). ICAO standards and recommended practices are from the document Annex 14 to the Convention on International Civil Aviation and from the referred documents. In turn, FAA documents herein addressed are the Airport Design: Advisory Circular 150/5300-13 and others referred in this one. By following a proposed design criteria framework, ICAO and FAA standards and recommended practices are compared. From such comparison, it is shown the differences in specifications itself and also in the way by which ICAO and FAA specify their standards. For the cases where direct comparisons are not possible, it is used a set of aircrafts of known characteristics. For the most complex design criteria, mathematical equations are also proposed. Another addressed issue is the flexibilization of design standards, which aims the accommodation of A380-800 and B747-8 aircrafts at existing airports. The ICAO flexibilizations are made from conclusions of the A380 Airport Compatibility Group (AACG) and the Boeing 747-8 Airport Compatibility Group (BACG). FAA flexibilizations are from this same agency, namely through EBs (Engineering Briefs). Lastly, the addressed design criteria are applied to analyse the operation of A380-800 and B747-8 aircrafts at São Paulo/Guarulhos International Airport.
3

Análise dos padrões e recomendações da ICAO e da FAA para o projeto geométrico de aeródromos. / Analysis of ICAO and FAA standards and recommendations for aerodrome geometric design.

Evandro José da Silva 22 March 2012 (has links)
Esta pesquisa de mestrado aborda o projeto geométrico de aeródromos a partir dos padrões e recomendações da ICAO (International Civil Aviation Organization) e da FAA (Federal Aviation Administration). Os padrões e recomendações da ICAO foram extraídos do documento Annex 14 to the Convention on International Civil Aviation e de documentos por ele referenciados. Para o caso da FAA, serviu de base o documento Airport Design: Advisory Circular 150/5300-13, incluindo-se aqueles nele referenciados e considerados pertinentes ao escopo do estudo. Seguindo-se uma estrutura de critérios de projeto proposta, os padrões e recomendações da ICAO e da FAA são comparados entre si, explicitando-se as diferenças nas especificações em si e também na forma como estas especificações são feitas por cada norma. Para o caso em que comparações diretas não são possíveis, as comparações são feitas a partir de um conjunto de aeronaves com características conhecidas. No caso dos critérios cuja avaliação é mais complexa, equacionamentos matemáticos são propostos. Apresenta-se também uma série de flexibilizações dos padrões, as quais são voltadas à acomodação das aeronaves A380-800 e B747-8 em aeroportos existentes. Estas flexibilizações provêm das conclusões do A380 Airport Compatibility Group (AACG) e do Boeing 747-8 Airport Compatibility Group (BACG), no caso dos padrões da ICAO. Para a as flexibilizações dos padrões da FAA, servem de base os Engineering Briefs (EBs) por ela emitidos. Finalmente, com base nos critérios de projeto considerados, é feita uma análise do Aeroporto Internacional de São Paulo/Guarulhos quanto à operação das aeronaves A380-800 e B747-8. / This Master Thesis tackles aerodrome geometric design according to the standards and recommended practices from the ICAO (International Civil Aviation Organization) and the FAA (Federal Aviation Administration). ICAO standards and recommended practices are from the document Annex 14 to the Convention on International Civil Aviation and from the referred documents. In turn, FAA documents herein addressed are the Airport Design: Advisory Circular 150/5300-13 and others referred in this one. By following a proposed design criteria framework, ICAO and FAA standards and recommended practices are compared. From such comparison, it is shown the differences in specifications itself and also in the way by which ICAO and FAA specify their standards. For the cases where direct comparisons are not possible, it is used a set of aircrafts of known characteristics. For the most complex design criteria, mathematical equations are also proposed. Another addressed issue is the flexibilization of design standards, which aims the accommodation of A380-800 and B747-8 aircrafts at existing airports. The ICAO flexibilizations are made from conclusions of the A380 Airport Compatibility Group (AACG) and the Boeing 747-8 Airport Compatibility Group (BACG). FAA flexibilizations are from this same agency, namely through EBs (Engineering Briefs). Lastly, the addressed design criteria are applied to analyse the operation of A380-800 and B747-8 aircrafts at São Paulo/Guarulhos International Airport.
4

LOCALIZATION ON SPERM, QUANTIFICATION AND MOLECULAR FEATURES OF TWO SEMINAL PROTEINS

Dawson, George Ray January 2005 (has links)
Objective markers to identify higher fertility individuals are needed to maximize livestock breeding success. Two heparin-binding proteins, which are reflective of fertility in bulls, have been biochemically identified as fertility-associated antigen (FAA) and tissue inhibitor of metalloproteinases-2 (TIMP-2). These four studies were designed to examine the importance of those proteins in relation to reproduction in bulls and other livestock species. In the first study, indirect immuno-fluorescent microscopy was performed to localize FAA and TIMP-2 to livestock sperm. FAA was localized on spermatozoal acrosomes of bulls and rams, but no cross-reactivity was observed for stallions. TIMP-2 labeling was observed on acrosomes and posterior heads, which was species dependent. Localization patterns for FAA and TIMP-2 were further investigated during heparin-induced capacitation and acrosome reactions of bovine sperm. In study two, an enzyme-linked immunosorbent assay (ELISA) was developed to determine concentrations of FAA in bovine seminal plasma (SP). A commercially available TIMP-2 ELISA was utilized to quantify TIMP-2. Respective mean concentrations of FAA and TIMP-2 in SP were 6.661.487 ug/ml and 1.180.045 mg/ml. Concentrations of FAA in SP did not correspond to bull fertility potential, however, older bulls with higher concentrations of TIMP-2 in SP sired more calves. The third study evaluated utility of an amplified fragment length polymorphism with bovine TIMP-2 gene specific primers to amplify a 700 bp genomic DNA (gDNA) product from sperm. From 53 bulls screened, 22.6% were negative for the 700 bp amplicon. There was a three-fold likelihood for 700 bp negative bulls to not sire a calf compared to 700 bp positive bulls. The product was cloned and sequenced, but no homology to TIMP-2 was detected. Therefore, the product represented novel bovine gDNA sequence. The fourth study identified an equine homologue to the bovine FAA gene. Immuno-based diagnostics had not detected FAA in stallion semen. The equine DNA homologue was 88.5% identical in nucleotide and 86% in amino acid sequences to bovine FAA. Subtle differences in the amino acid sequence are likely responsible for the inability to detect FAA in stallion semen with FAA antibodies to bovine FAA.
5

Pubertal changes in the expression of fertility associated antigen in Bos indicus and Bos taurus bulls

Novosad, Aaron M. 25 April 2007 (has links)
Fertility Associated Antigen (FAA) produced by the accessory sex glands and contained within the seminal fluid binds heparin and facilitates capacitation in ejaculated sperm, resulting in improved fertility in bulls capable of producing the protein. In this study, a total of 206 bulls derived from three populations were evaluated for the presence or absence of FAA through utilization of the Repro Test at three semen collections over a 60-d period. Across all collections, the percentage of FAA Negative bulls ranged from 13.64 to 36.11%. Within the three populations, 32, 33, and 67 bulls were observed at three different collections, of which 3.03, 9.09 and 4.48% were FAA Negative at all three collections, respectively. Furthermore, 27.27, 33.33, and 20.90% of bulls were observed to have variations within their FAA status after providing an initial FAA Positive result, respectively. Bull age, sperm concentration, progressive forward motility, percent normal sperm, ejaculate volume, and scrotal circumference were determined to be significantly different between FAA Negative and FAA Positive bulls in at least one collection. However, no consistent trend was observed across populations, or collections within a population, with regard to a relationship between these variables and FAA. Furthermore, of fourteen bulls that produced an ejaculate in which no sperm was detected, 78.57% (n=11) were FAA Positive despite the lack of sperm within the ejaculate. No single variable commonly measured to determine bull fertility was consistent in predicting the FAA status of bulls. The ability to produce FAA precedes puberty and the Repro Test can be used to identify FAA in prepuberal bulls. However, a large percentage of bulls, both prepuberal and peripuberal, are capable of displaying variation in their FAA status (as determined by the Repro Test) over time.
6

Progress in Global Air Traffic Management (GATM) Avionics System Test at the Air Force Flight Test Center

Switzer, Earl R., Fleishans, Amy D. 10 1900 (has links)
International Telemetering Conference Proceedings / October 22-25, 2001 / Riviera Hotel and Convention Center, Las Vegas, Nevada / This paper presents a progress report on Global Air Traffic Management (GATM) avionic system test activities at the Air Force Flight Test Center. In many parts of the world today the continuing growth of commercial air traffic is running up against limits brought on by overuse of aviation resources. Air corridors in Europe and on transoceanic air routes are operating at maximum capacity. Civil Aviation Authorities (CAAs) are working these challenges on two levels—near-term incremental improvements and long-term visionary changes. Each country has a CAA; ours being the Federal Aviation Administration (FAA). Near-term solutions focus on better utilization of resources such as air space and frequency spectrum and improved performance of air traffic control facilities. Long-term visionary changes, such as free flight, could fundamentally change the current civil aviation business process model. CAA policies and standards are driving near-term improvements and migration toward long-term objectives. This initiative is referred as Communication Navigation Surveillance/Air Traffic Management (CNS/ATM). Implementation of the U.S. military’s vision, Global Reach/Global Power, requires the ability to rapidly deploy armed forces to major regional conflicts anywhere in the world, and to sustain these forces for as long as it takes to resolve these conflicts. To achieve this goal and accomplish rapid deployments while at the same time minimizing costs, the Air Force has adopted a solution that makes extensive use of CNS/ATM. The Air Force calls its initiative Global Air Traffic Management (GATM). Air Force aircraft equipped with GATM avionics will be able to use CNS/ATM capabilities such as reduced vertical separation minimum (RVSM), 8.33 kHz data links, automatic dependent surveillance - broadcast (ADS-B), and global communication networks. These capabilities make possible improved flight safety, lower fuel costs, and quicker turn times. The Air Force Flight Test Center supports the GATM initiative by providing Air Traffic Control (ATC) Communications Test Facilities and Avionic System Test (ACTFAST) capabilities to support aircraft modification programs.
7

Improvements in Numerical Modeling Methodology of Dry Woven Fabrics for Aircraft Engine Containment Systems

January 2012 (has links)
abstract: Woven fabric composite materials are widely used in the construction of aircraft engine fan containment systems, mostly due to their high strength to weight ratios and ease of implementation. The development of a predictive model for fan blade containment would provide great benefit to engine manufactures in shortened development cycle time, less risk in certification and fewer dollars lost to redesign/recertification cycles. A mechanistic user-defined material model subroutine has been developed at Arizona State University (ASU) that captures the behavioral response of these fabrics, namely Kevlar® 49, under ballistic loading. Previously developed finite element models used to validate the consistency of this material model neglected the effects of the physical constraints imposed on the test setup during ballistic testing performed at NASA Glenn Research Center (NASA GRC). Part of this research was to explore the effects of these boundary conditions on the results of the numerical simulations. These effects were found to be negligible in most instances. Other material models for woven fabrics are available in the LS-DYNA finite element code. One of these models, MAT234: MAT_VISCOELASTIC_LOOSE_FABRIC (Ivanov & Tabiei, 2004) was studied and implemented in the finite element simulations of ballistic testing associated with the FAA ASU research. The results from these models are compared to results obtained from the ASU UMAT as part of this research. The results indicate an underestimation in the energy absorption characteristics of the Kevlar 49 fabric containment systems. More investigation needs to be performed in the implementation of MAT234 for Kevlar 49 fabric. Static penetrator testing of Kevlar® 49 fabric was performed at ASU in conjunction with this research. These experiments are designed to mimic the type of loading experienced during fan blade out events. The resulting experimental strains were measured using a non-contact optical strain measurement system (ARAMIS). / Dissertation/Thesis / M.S. Civil and Environmental Engineering 2012
8

Sistema de gerência de pavimentos aeroportuários: estudo de caso no Aeroporto Estadual de Araraquara / Airport pavement management system: a case study in Araraquara State Airport

Cossío Durán, Jorge Braulio 26 February 2015 (has links)
A presente pesquisa objetiva contribuir para a implantação de Sistemas de Gerência de Pavimentos Aeroportuários (SGPA), tendo por base um estudo de caso desenvolvido no Aeroporto Estadual de Araraquara-SP Bartolomeu de Gusmão. Foi criado um banco de dados informatizado, através do FAA PAVEAIR, programa computacional de gerência de pavimentos aeroportuários disponibilizado pelo FAA (Federal Aviation Administration), que permitiu o armazenamento de toda informação inerente aos pavimentos do complexo aeroportuário e a determinação, com base no método PCI (Pavement Condition Index), da condição atual da pista de pousos e decolagens, da pista de rolagem e do pátio de aeronaves. Os resultados mostraram que o aeroporto de Araraquara apresenta condição regular de operação, indicada por um PCI médio de 67, e que os principais defeitos encontrados foram desagregação das partículas da mistura asfáltica, trincas transversais e, principalmente, trincas longitudinais. Por conseguinte, foram planejadas intervenções de manutenção e reabilitação, de modo a evitar situações que levassem ao comprometimento geral da condição dos pavimentos e, por consequência, a um aumento significativo dos custos de conservação. A melhor estratégia, se aplicada ao longo dos vinte anos de período de projeto, resultaria em um valor de PCI médio igual a 77, correspondente a boas condições de operação. Dessa forma, o estudo de caso desenvolvido contribuiu, com um exemplo completo, para a implantação de um SGPA em nível de rede e, mais ainda, para o desenvolvimento de um SGPA integral para a rede de aeroportos de administrações aeroportuárias de pequeno, médio e grande portes no Brasil, o que deve ser precedido pela elaboração de legislação específica que exija a aplicação efetiva de técnicas de manutenção que prolonguem a vida útil dos pavimentos, especialmente devido ao aumento da demanda por transporte aéreo e à necessidade de modernas e potentes aeronaves, que requerem, cada vez mais, melhores condições funcionais e estruturais das pistas de pousos e decolagens e dos pátios de aeronaves dos aeroportos. / This research aims to contribute to the implementation of Airport Pavements Management Systems (SGPA), based on a case study developed at the Araraquara State Airport Bartolomeu de Gusmao, in the State of Sao Paulo, Brazil. A computerized database was created, using the FAA PAVEAIR, an airport pavement management computer program provided by the FAA (Federal Aviation Administration), which allowed the storage all information inherent to the airport complex facilities and determining, based on the method of PCI (Pavement Condition Index), the current condition of the runway, taxiway and apron. The results showed that the airport presents regular operating condition, indicated by an average PCI of 67, and that the main defects found were raveling, transverse cracks and mainly longitudinal cracks. Therefore, maintenance and rehabilitation operations are planned so as to avoid situations that could lead to impairment of the general condition of the pavement and, consequently, a significant increase of maintenance costs. The best strategy, if applied over the twenty-year project period, would result in average PCI value of 77, corresponding to good operating condition. Thus, the case study developed contributed with a complete example, for the implementation of a SGPA network-level and even more so for the development of a comprehensive SGPA to the airport network of administrations of small, medium and large airports in Brazil, which should be preceded by the enactment of specific legislation that requires the effective application of maintenance techniques that prolong the life of pavements, especially due to increased demand for air transport and the need for modern and powerful aircraft, requiring increasingly, better functional and structural conditions of runways and aprons.
9

Sistema de gerência de pavimentos aeroportuários: estudo de caso no Aeroporto Estadual de Araraquara / Airport pavement management system: a case study in Araraquara State Airport

Jorge Braulio Cossío Durán 26 February 2015 (has links)
A presente pesquisa objetiva contribuir para a implantação de Sistemas de Gerência de Pavimentos Aeroportuários (SGPA), tendo por base um estudo de caso desenvolvido no Aeroporto Estadual de Araraquara-SP Bartolomeu de Gusmão. Foi criado um banco de dados informatizado, através do FAA PAVEAIR, programa computacional de gerência de pavimentos aeroportuários disponibilizado pelo FAA (Federal Aviation Administration), que permitiu o armazenamento de toda informação inerente aos pavimentos do complexo aeroportuário e a determinação, com base no método PCI (Pavement Condition Index), da condição atual da pista de pousos e decolagens, da pista de rolagem e do pátio de aeronaves. Os resultados mostraram que o aeroporto de Araraquara apresenta condição regular de operação, indicada por um PCI médio de 67, e que os principais defeitos encontrados foram desagregação das partículas da mistura asfáltica, trincas transversais e, principalmente, trincas longitudinais. Por conseguinte, foram planejadas intervenções de manutenção e reabilitação, de modo a evitar situações que levassem ao comprometimento geral da condição dos pavimentos e, por consequência, a um aumento significativo dos custos de conservação. A melhor estratégia, se aplicada ao longo dos vinte anos de período de projeto, resultaria em um valor de PCI médio igual a 77, correspondente a boas condições de operação. Dessa forma, o estudo de caso desenvolvido contribuiu, com um exemplo completo, para a implantação de um SGPA em nível de rede e, mais ainda, para o desenvolvimento de um SGPA integral para a rede de aeroportos de administrações aeroportuárias de pequeno, médio e grande portes no Brasil, o que deve ser precedido pela elaboração de legislação específica que exija a aplicação efetiva de técnicas de manutenção que prolonguem a vida útil dos pavimentos, especialmente devido ao aumento da demanda por transporte aéreo e à necessidade de modernas e potentes aeronaves, que requerem, cada vez mais, melhores condições funcionais e estruturais das pistas de pousos e decolagens e dos pátios de aeronaves dos aeroportos. / This research aims to contribute to the implementation of Airport Pavements Management Systems (SGPA), based on a case study developed at the Araraquara State Airport Bartolomeu de Gusmao, in the State of Sao Paulo, Brazil. A computerized database was created, using the FAA PAVEAIR, an airport pavement management computer program provided by the FAA (Federal Aviation Administration), which allowed the storage all information inherent to the airport complex facilities and determining, based on the method of PCI (Pavement Condition Index), the current condition of the runway, taxiway and apron. The results showed that the airport presents regular operating condition, indicated by an average PCI of 67, and that the main defects found were raveling, transverse cracks and mainly longitudinal cracks. Therefore, maintenance and rehabilitation operations are planned so as to avoid situations that could lead to impairment of the general condition of the pavement and, consequently, a significant increase of maintenance costs. The best strategy, if applied over the twenty-year project period, would result in average PCI value of 77, corresponding to good operating condition. Thus, the case study developed contributed with a complete example, for the implementation of a SGPA network-level and even more so for the development of a comprehensive SGPA to the airport network of administrations of small, medium and large airports in Brazil, which should be preceded by the enactment of specific legislation that requires the effective application of maintenance techniques that prolong the life of pavements, especially due to increased demand for air transport and the need for modern and powerful aircraft, requiring increasingly, better functional and structural conditions of runways and aprons.
10

Rehabilitación de pavimentos del Aeropuerto del Cusco usando modificadores de asfalto

Martínez Ismodes, Juan Carlos, Ventocilla Alva, Juan Carlos January 2009 (has links)
La presente tesis es el resultado de una interacción de evaluaciones de campo como los resultados de los ensayos del sistema de canteras, pavimento existente, humedad natural, mix de aeronaves que operan y de topografía, así mismo de la traducción de manuales y catálogos, ya que nuestro País está afiliado y se rige por las Normas de la Organización de Aviación Civil Internacional (OACI), por los métodos de diseño de la Federal Aviation Administration (FAA) entidad oficial de la aeronáutica civil en los E.E.U.U. y a las especificaciones técnicas para al construcción de aeropuertos.

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