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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.
71

Effect of early grain feeding of steers on postabsorptive capacity to utilize acetate and glucose

Wettathperuma Arachchige, Deepthi Nayananjalie 12 December 2012 (has links)
The aims of the first study were to determine the effects of early weaning followed by a period of high-grain feeding on signaling protein phosphorylation in muscle and on acetate clearance in growing steers.  Twelve Angus X Simmental steers were used in the study.  Six steers were weaned early (EW) and fed a high-gain diet for 148 d and the remainder were weaned at the normal age (NW).  Longissimus muscle tissue biopsies were collected to determine total and phosphorylated forms of AMP kinase and downstream proteins of the mTOR signaling pathway.   Of the 12, 8 steers were used to assess acetate clearance at different age points.  During early grain feeding, phosphorylated:total ratios of rpS6 and S6K1 were greater in EW steers and they had lower acetate clearance rates and greater synthesis rates.   The objectives of second study were to assess the effects of early grain feeding on acetate and glucose turnover rates, palmitate synthesis, and on acetate and glucose preference by subcutaneous, intramuscular and visceral adipose tissues in finishing steers.  Sixteen Angus x Simmental steers were infused continuously with [2H3] acetate (n = 8) or [U-13C6] glucose (n = 8), over a 12 h period immediately prior to harvest.  Plasma acetate and glucose enrichment, and palmitate enrichment in different adipose tissue locations were determined.  There were no treatment effects on acetate or glucose turnover rates or palmitate fractional synthesis rates (FSR).  Acetate turnover and palmitate FSR from acetate were greater than the corresponding rates from glucose.  There were no differences in preference for acetate or glucose among the fat depots. In conclusion, phosphorylation ratios of signaling proteins were not affected treatment.  Acetate clearance increased when steers were heavier and older.  Thus older calves are able to clear more acetate per unit of time and body mass than younger calves reflective of an enhanced ability to utilize the substrate.  There were no differences in preference for acetate and glucose among the major fat depots.  Thus diets leading to high glucose supply will not preferentially direct energy storage to intramuscular stores. / Ph. D.
72

The addition of stripes (a version of the ‘horizontal-vertical illusion’) increases foot clearance when crossing low-height obstacles

Foster, Richard J., Buckley, John, Whitaker, David J., Elliott, David B. 17 November 2015 (has links)
Yes / Trips over obstacles are one of the main causes of falling in older adults, with vision playing an important role in successful obstacle negotiation. We determined whether a horizontal-vertical illusion, superimposed onto low-height obstacles to create a perceived increase in obstacle height, increased foot clearances during obstacle negotiation thus reducing the likelihood of tripping. Eleven adults (mean ± 1 SD: age 27.3 ± 5.1 years) negotiated obstacles of varying heights (3, 5, 7 cm) with four different appearance conditions; two were obstacles with a horizontal-vertical illusion (vertical stripes of different thickness) superimposed on the front, one was a plain obstacle and the fourth a plain obstacle with a horizontal black line painted on the top edge. Foot clearance parameters were compared across conditions. Both illusions led to a significant increase in foot clearance when crossing the obstacle, compared to the plain condition, irrespective of obstacle height. Superimposing a horizontal-vertical illusion onto low-height obstacles can increase foot clearance, and its use on the floor section of a double-glazing door frame for example may reduce the incidence of tripping in the home.
73

Avaliação da função renal pelo Clearance de Creatinina, dos pacientes vítimas de acidente ofídico no Hospital de Referência de Porto Nacional Tocantins (2013-2014) / Renal function assessment by Creatinine Clearance on patients victims of ophidic accident at Referral Hospital in Porto Nacional, Tocantins State (2013-2014)

Magalhães Filho, Asterio Souza 18 December 2015 (has links)
O Hospital de Referência de Porto Nacional no estado do Tocantins é responsável pelo atendimento da população desta cidade e de mais treze municípios circunvizinhos que compreendem a Regional de Saúde Amor Perfeito pela SESAU TO. Totalizando aproximadamente 180.000 habitantes, grande parte dessa população reside na zonal rural e mesmo os habitantes das zonas urbanas frequentam ambientes selvagens como beira de rios e matas, o que os expõe ao contato com animais peçonhentos. Os acidentes ofídicos ocorridos nesta região são atendidos, quase que exclusivamente, nesta unidade hospitalar e a disfunção renal é uma das mais temíveis complicações nesses casos. Esse estudo epidemiológico visa realizar diagnóstico de disfunção renal em pacientes vítimas de acidente ofídico, e acompanhamento evolutivo do quadro clínico pela mensuração do clearance de creatinina com o método indireto utilizando a Fórmula de Cockroft e Gault. Foi realizado o acompanhamento clínico de todos os pacientes atendidos no Hospital de Referência de Porto Nacional vítimas de acidente ofídico de qualquer gênero no período de janeiro de 2013 a dezembro de 2014. A mensuração do clearance de creatinina foi realizada no momento do primeiro atendimento e posteriormente em acompanhamento diário da Taxa de Filtração Glomerular usando a Fórmula de Cockroft e Gault (140-Peso-kg) x Idade em anos / 72 x creatinina plasmática. Durante o período estudado foram atendidos neste hospital 78 casos de acidente ofídico, dos quais 88,4% classificados como acidente Botrópico e 6,4% como Crotálico. O clearance de creatinina ficou abaixo de 60 ml/min/m², o que comprova disfunção renal, em 12 pacientes, demonstrando uma incidência geral de 15,4%. A incidência de acidente Botrópico foi de 15,9 % enquanto que a do tipo Crotálico foi de 20%. Todos os pacientes restabeleceram a função renal normal após término do tratamento. A maioria dos casos ocorreu nos meses de janeiro, fevereiro, novembro e dezembro, onde ocorrem as maiores incidências de chuvas. Fatores como idade do paciente e o tempo entre o acidente e o início da terapia específica, com soro adequado, contribuíram para o surgimento da Insuficiência Renal Aguda pós-acidente ofídico. O conhecimento do perfil epidemiológico de cada região aliado ao estudo das taxas de incidência, prevalência e complicações desta entidade clínica, bem como o início precoce da terapêutica adequada interferem no surgimento de lesões renais com pior prognóstico. / The Referral Hospital in Porto Nacional, Tocantins state, is responsible for serving the population of this city and thirteen surrounding municipalities that comprise the Regional Health Office called \"Perfect Love\" administrated by SESAU-TO healthy authority. With approximately 180,000 inhabitants in total, much of this population lives in the rural zone, and even the urban dwellers attend wild environments such as river banks and forests, which is putting them in contact with venomous animals. The ophidic accidents occurred in this region are treated almost exclusively in this hospital unite and renal dysfunction is one of the most feared complications in these cases. This epidemiological study aims at performing diagnosis of renal dysfunction in patients suffering from ophidic accident, and the monitoring evolution of the clinical picture by measuring creatinine clearance with an indirect method by using the Cockroft and Gault formula. Clinical follow-ups were performed in all patients treated at the Referral Hospital in Porto Nacional city, Tocantins state, which were victims of any kind of ophidic accident from January 2013 to December 2014. The measurement of creatinine clearance was done at the first doctor visit and later in a daily basis for monitoring glomerular filtration rate using the formula of Cockroft and Gault (140-kg-weight) x Age in years / 72 x plasmatic creatinine. During the study period, 78 cases of ophidic accidents were treated. 88.4% were classified as Bothropic accident and 6.4% Crotalic one. The creatinine clearance level was below 60 ml / min / m², which proves renal dysfunction in 12 patients, leading to an overall incidence of 15.4%. When separated by type of accident, the incidence for Bothropic accident was 15.9% while the Crotalic type was 20%. All patients restored normal renal function after the end of treatment. Most cases occurred in January, February, November and December, when the highest incidence of rainfall occurs. Factors such as patient age, time between the accident and early specific therapy with appropriate serum contributed to the emergence of acute renal failure in the post-ophidic accident period. The knowledge of the epidemiological profile of each region together with the study of incidence rates, prevalence and complications of this clinical entity, as well as the early initiation of appropriate therapy interferes with the appearance of renal lesions with poor prognosis.
74

Determinantes do clearance da infecção pelo Papilomavírus Humano (HPV) em mulheres em idade reprodutiva influência de fatores comportamentais, coinfecções sexualmente transmissíveis e resposta imune inata /

Pinto, Gabriel Vitor da Silva. January 2019 (has links)
Orientador: Márcia Guimarães da Silva / Resumo: Objetivo: O objetivo do presente estudo foi identificar determinantes do clearance da infecção pelo Papilomavírus Humano (HPV) em mulheres brasileiras em idade reprodutiva. Métodos: Trata-se de estudo de coorte denominado HPV-UNESP, no qual 1638 mulheres em idade reprodutiva foram recrutadas no período de setembro de 2012 e janeiro de 2013. Desse total, 544 mulheres positivas para a infecção pelo HPV participaram do seguimento longitudinal durante 30 meses, em mais 4 visitas. A infecção por HPV foi definida como detecção de qualquer um dos 36 genótipos testados pelo Linear Array Genotyping Test (Roche Molecular Systems, Inc.) e o desfecho de interesse foi o clearance da infecção, definido como a eliminação da infecção pelo HPV por, pelo menos, duas visitas consecutivas. Um questionário estruturado com 58 questões relativas à dados sociodemográficos, características comportamentais e ginecológicas foi aplicado em cada visita. Imediatamente após a entrevista, todas as mulheres realizaram exame ginecológico, no qual, após inserção de espéculo de Collins, não lubrificado, foi aferido o pH vaginal com fita (pH 4.0-7.0, Merck, Germany) no terço médio da parede vaginal. Para avaliação da microbiota vaginal, amostras foram coletadas com swab da parede vaginal e o padrão de microbiota foi classificado de acordo com os critérios de Nugent et al. (1991). O whiff test realizado por adição de solução de 10% de KOH ao conteúdo vaginal foi interpretado como positivo, negativo ou duvidoso. A... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Objective: The objective of the present study was to identify determinants of Human Papillomavirus (HPV) infection clearance in Brazilian women of reproductive age. Methods: This is a cohort study called HPV-UNESP, in which 1638 women of reproductive age were recruited from September 2012 to January 2013. Of this total, 544 women positive for HPV infection participated in longitudinal follow-up for 30 months, in 4 more visits. HPV infection was defined as detection of any of the 36 genotypes tested by the Linear Array Genotyping Test (Roche Molecular Systems, Inc.) and the outcome of interest was infection clearance, defined as the elimination of HPV infection by least two consecutive visits. A structured questionnaire with 58 questions regarding sociodemographic data, behavioral and gynecological characteristics was applied at each visit. Immediately after the interview, all women underwent a gynecological exam, in which, after insertion of the non-lubricated Collins speculum, the vaginal pH with tape (pH 4.0-7.0, Merck, Germany) was measured in the middle third of the vaginal wall. For vaginal microbiota evaluation, samples were collected with vaginal wall swab and the microbiota pattern was classified according to the criteria of Nugent et al. (1991). The whiff test performed by adding 10% KOH solution to the vaginal content was interpreted as positive, negative or doubtful. Endocervical samples were collected with cytobrush for molecular analysis of HPV, Chlamydia trachom... (Complete abstract click electronic access below) / Doutor
75

Dynamic Ground Clearance

Hamache, Violette January 2013 (has links)
The purpose of this work is to develop a test method which will consider the variation of the ground clearance when driving, the so-called dynamic ground clearance. This has been done through the analysis of a specific application: the tractors in grain used in Brazil. Series of real life tests are run in order to obtain data on the tire compressions and the suspension travels. The tractor used is a 6x4 and is loaded with a trailer. When investigating critical cases, the minimum dynamic ground clearance is found to be as small as 123 mm at the axle 1, 78 mm at the exhaust outlet, 137 mm at the fuel tank, 35 mm at the bumper and 213 mm at the axle 2. These data will be transmitted to the engineer responsible for the chassis design in order for him to get a better understanding of the motion of the truck relative to ground.
76

SARS’powers with regard to tax clearance certificates

Msiza, Vusumuzi Frank 09 1900 (has links)
The study aims to review the regulatory powers exercised by the South African Revenue Services (SARS) with regard to the issuing, decline or revocation of a taxpayer’s tax clearance certificate, to highlight any remedial measures and procedures available to the aggrieved taxpayer in order to protect the right of taxpayers to fair administrative action in their dealings with SARS. Previously, a tax clearance certificate was not issued in terms of any statute or provision of any Tax Act. However, since the introduction of the Tax Administration Act, as amended (TAA), the issuing of the tax clearance certificates are more efficiently regulated. The issuing of tax clearance certificate’s must conform to the values and principles prescribed for under current legislation, and more particularly, as espoused under the Constitution of South Africa, 1996 (the Constitution). However, it has been reported some taxpayer were experiencing unreasonable and incomprehensible delays in obtaining responses to the objections lodged with SARS for assessment. Taxpayers seeking resolution of their disputes with SARS, currently opt to incur litigation costs in order to obtain appropriate relief from the High Courts. Taxpayers must take note that there is nothing in Promotion of Administrative Justice Act (PAJA) or the common law, which empowers a Court to order an administrator to take action, including the making of a decision which the administrator is not lawfully allowed to make. The study highlights remedial measures and procedures available to the aggrieved taxpayer to prevent the misapplication of fiscal power by SARS in the issuing of the taxpayer’s compliance status, thus protecting the right to fair administrative action in their dealings with SARS. Taxpayers who are aggrieved by a decision taken by the Revenue Authority are encouraged to timeously address their grievances, commencing with the internal dispute resolution remedies provided for within the TAA. / Taxation
77

Avaliação da função renal pelo Clearance de Creatinina, dos pacientes vítimas de acidente ofídico no Hospital de Referência de Porto Nacional Tocantins (2013-2014) / Renal function assessment by Creatinine Clearance on patients victims of ophidic accident at Referral Hospital in Porto Nacional, Tocantins State (2013-2014)

Asterio Souza Magalhães Filho 18 December 2015 (has links)
O Hospital de Referência de Porto Nacional no estado do Tocantins é responsável pelo atendimento da população desta cidade e de mais treze municípios circunvizinhos que compreendem a Regional de Saúde Amor Perfeito pela SESAU TO. Totalizando aproximadamente 180.000 habitantes, grande parte dessa população reside na zonal rural e mesmo os habitantes das zonas urbanas frequentam ambientes selvagens como beira de rios e matas, o que os expõe ao contato com animais peçonhentos. Os acidentes ofídicos ocorridos nesta região são atendidos, quase que exclusivamente, nesta unidade hospitalar e a disfunção renal é uma das mais temíveis complicações nesses casos. Esse estudo epidemiológico visa realizar diagnóstico de disfunção renal em pacientes vítimas de acidente ofídico, e acompanhamento evolutivo do quadro clínico pela mensuração do clearance de creatinina com o método indireto utilizando a Fórmula de Cockroft e Gault. Foi realizado o acompanhamento clínico de todos os pacientes atendidos no Hospital de Referência de Porto Nacional vítimas de acidente ofídico de qualquer gênero no período de janeiro de 2013 a dezembro de 2014. A mensuração do clearance de creatinina foi realizada no momento do primeiro atendimento e posteriormente em acompanhamento diário da Taxa de Filtração Glomerular usando a Fórmula de Cockroft e Gault (140-Peso-kg) x Idade em anos / 72 x creatinina plasmática. Durante o período estudado foram atendidos neste hospital 78 casos de acidente ofídico, dos quais 88,4% classificados como acidente Botrópico e 6,4% como Crotálico. O clearance de creatinina ficou abaixo de 60 ml/min/m², o que comprova disfunção renal, em 12 pacientes, demonstrando uma incidência geral de 15,4%. A incidência de acidente Botrópico foi de 15,9 % enquanto que a do tipo Crotálico foi de 20%. Todos os pacientes restabeleceram a função renal normal após término do tratamento. A maioria dos casos ocorreu nos meses de janeiro, fevereiro, novembro e dezembro, onde ocorrem as maiores incidências de chuvas. Fatores como idade do paciente e o tempo entre o acidente e o início da terapia específica, com soro adequado, contribuíram para o surgimento da Insuficiência Renal Aguda pós-acidente ofídico. O conhecimento do perfil epidemiológico de cada região aliado ao estudo das taxas de incidência, prevalência e complicações desta entidade clínica, bem como o início precoce da terapêutica adequada interferem no surgimento de lesões renais com pior prognóstico. / The Referral Hospital in Porto Nacional, Tocantins state, is responsible for serving the population of this city and thirteen surrounding municipalities that comprise the Regional Health Office called \"Perfect Love\" administrated by SESAU-TO healthy authority. With approximately 180,000 inhabitants in total, much of this population lives in the rural zone, and even the urban dwellers attend wild environments such as river banks and forests, which is putting them in contact with venomous animals. The ophidic accidents occurred in this region are treated almost exclusively in this hospital unite and renal dysfunction is one of the most feared complications in these cases. This epidemiological study aims at performing diagnosis of renal dysfunction in patients suffering from ophidic accident, and the monitoring evolution of the clinical picture by measuring creatinine clearance with an indirect method by using the Cockroft and Gault formula. Clinical follow-ups were performed in all patients treated at the Referral Hospital in Porto Nacional city, Tocantins state, which were victims of any kind of ophidic accident from January 2013 to December 2014. The measurement of creatinine clearance was done at the first doctor visit and later in a daily basis for monitoring glomerular filtration rate using the formula of Cockroft and Gault (140-kg-weight) x Age in years / 72 x plasmatic creatinine. During the study period, 78 cases of ophidic accidents were treated. 88.4% were classified as Bothropic accident and 6.4% Crotalic one. The creatinine clearance level was below 60 ml / min / m², which proves renal dysfunction in 12 patients, leading to an overall incidence of 15.4%. When separated by type of accident, the incidence for Bothropic accident was 15.9% while the Crotalic type was 20%. All patients restored normal renal function after the end of treatment. Most cases occurred in January, February, November and December, when the highest incidence of rainfall occurs. Factors such as patient age, time between the accident and early specific therapy with appropriate serum contributed to the emergence of acute renal failure in the post-ophidic accident period. The knowledge of the epidemiological profile of each region together with the study of incidence rates, prevalence and complications of this clinical entity, as well as the early initiation of appropriate therapy interferes with the appearance of renal lesions with poor prognosis.
78

CCX - Enormer Funktionalitätssprung. CCX löst SAX in Creo4 für die Berechnung von Luft- und Kriechstrecken ab

Bruns, Christoph 02 July 2018 (has links)
- Luft- und Kriechstreckenberechnung in 3D-CAD-Daten - Neue, umfassendere Funktionalität in CCX - CCX löst Spark Analysis Extension ab - AutoCrea - Mehr Sicherheit im Entwurf von elektronischen Komponenten - Rasante Beschleunigung in der Geometrieauslegung zur Vermeidung von Risiken durch Luft- und Kriechstrecken - Deutliche Wertschöpfung schon in der Produktentwicklung in der Auslegung von elektronischen Komponenten
79

Estudo da ação do veneno de Tityus serrulatus sobre a expressão de transportadores de sódio e água em epitélio alveolar de rato / Effect of Tityus serrulatus venom on sodium and water trasporters in rat alveolar epithelium

Málaque, Ceila Maria Sant\'Ana 15 August 2012 (has links)
Acidentes escorpiônicos podem evoluir com edema pulmonar de origem cardiogênica e não cardiogênica. O clearance de edema pulmonar está relacionado principalmente ao transporte ativo de sódio do espaço alveolar para o interstício. O objetivo deste trabalho foi avaliar os efeitos do veneno de Tityus serrulatus e da dexametasona sobre a expressão dos transportadores de sódio e água e do TLR4 em pulmão de ratos. Foram utilizados ratos Wistar, divididos em três grupos: controle (salina); grupo Vn, que recebeu o veneno de T. serrulatus (3.8 mg/kg) por via intraperitoneal (ip), e o grupo Dx+Vn, que recebeu dexametasona (2.0 mg/kg) por via ip, uma hora antes da injeção do veneno. Os experimentos foram realizados uma hora após a injeção do veneno. Foram realizadas análise bioquímica e dosagens de citocinas no plasma. Nos pulmões foram estudados a expressão de -ENaC, Na+-K+- ATPase, NKCC1, AQP-5 e TRL4 através de western blotting, e a expressão do NF-kB e infiltração de células CD68+ (monócitos/macrófagos) e neutrófilos, através de imunoistoquímica. O veneno de T. serrulatus diminuiu a expressão pulmonar de -ENaC e AQP-5, enquanto aumentou a expressão do NKCC1. A dexametasona preveniu os efeitos do veneno sobre a expressão da -ENaC e NKCC1, mas não da AQP5. Não foi observada alteração da expressão da 1- Na+-K+-ATPase . A expressão do TLR4 foi maior nos animais envenenados que nos grupos Cont e Dx+Vn. O níveis plasmáticos de IL-6, IL-10 e TNF- estavam aumentados nos grupo Vn e Dx+Vn em relação ao controle. O infiltrado de células CD68+ foi maior no grupo Vn. A expressão de NF-kB e o infiltrado ne neutrófilos no tecido pulmonar foi semelhantes nos três grupos avaliados. Os resultados encontrados sugerem que o veneno de T. serrulatus tem efeito sobre as proteínas transportadoras de sódio em células do epitélio alveolar e também sobre a expressão do TLR4 em pulmão; a dexametasona pode regular essas ações / Scorpion envenomation can cause cardiogenic and noncardiogenic pulmonary edema. Pulmonary edema clearance is largely related to active Na+ transport out of the alveoli, rather than to reversal of Starling forces. Our objective was determine the effects of Tityus serrulatus venom and dexamethasone on the pulmonary expression of sodium and water transporters, and Toll-like receptor 4. Wistar rats were divided into groups and injected intraperitoneally: control (saline only); venom (T. serrulatus venom3.8 mg/kg body weight); and dexamethasone+venom (dexamethasone2.0 mg/kg body weight60 min before venom inoculation). At 60 min after venom inoculation, interleukin-6 and -10, together with tumor necrosis factor alpha, were analyzed in plasma. In lungs, we determined expression of the epithelial sodium channel alpha subunit; Na,K-ATPase alpha 1 subunit; Na-K-2Cl cotransporter, NKCC1; aquaporin 5; Toll-like receptor 4 (by Western blotting); and nuclear factor-kappa B. We determined CD68 and neutrophil counts by immunohistochemistry. In venom group lungs, the epithelial sodium channel alpha subunit and aquaporin 5 were markedly downregulated, whereas NKCC1 was elevated, although the Na,K-ATPase alpha 1 subunit was unaffected. Dexamethasone protected the epithelial sodium channel alpha subunit, NKCC1, and Toll-like receptor 4 but not aquaporin 5. Serum interleukin 6, interleukin 10, and tumor necrosis factor alpha were elevated in both groups, as was CD68 expression. Neutrophil counts and nuclear factor-kappa B expression were comparable across groups. Our data show that T. serrulatus venom alters sodium transport in alveolar epithelial cells and increases Toll-like receptor 4 expression. Dexamethasone appears to partially protect against those effects
80

Thermal control of gas turbine casings for improved tip clearance

Choi, Myeonggeun January 2015 (has links)
A thermal tip clearance control system provides a robust and flexible means of manipulating the closure between the casing and the rotating blade tips in a jet engine, reducing undesirable tip leakage flows. This may be achieved using an impingement cooling scheme on the external casing of the engine in conjunction with careful thermal management of internal over-tip seal segment cavity. For a reduction in thrust specific fuel consumption, the mass flow rate of air used for cooling must be minimised, be at as low a pressure as possible and delivered through a light weight structure surrounding the rotating components in the turbine. This thesis first characterises the effectiveness of a range of external impingement cooling arrangements in typical engine casing closure system. The effects of jet-to-jet pitch, number of jets, inline and staggered alignment of jets, arrays of jets on flange, on an engine representative casing geometry are assessed through comparison of the convective heat transfer coefficient distributions in a series of numerical studies. A baseline case is validated experimentally. The validation data allowed the suitability of different turbulence closure models to be assessed using a commercial RANS solver. Importantly for each configuration the thermal contraction of an idealised engine casing is predicted using thermo-mechanical finite element models, at a series of operating conditions representing engine idle to maximum take-off conditions. Cooling is provided by manifolds attached to the outside of the engine. The assembly tolerance of these components leads to variation in the standoff distance between the manifold and the casing. For cooling arrangements with promising performance, the study is extended to characterise the variation in closure with standoff distance. It is shown that where a sparse array of non-interacting jets is used the system can be made tolerant of large build misalignments. The casing geometry itself contributes to the thermal response of the system, and, in an additional study, the effect of casing thickness and circumferential thermal control flanges are investigated. Restriction of the passage of heat into the flanges was seen to be dramatically change their effectiveness and slight necking of the flanges at their root was shown to improve the performance disproportionally. High temperature secondary air flowing past the internal face of the engine casing tends to heat the casing, causing it to grow. Experimental and numerical characterisation of a heat transfer within a typical over-tip segment cavity heat transfer is presented in this thesis for the first time. A simplified modelling strategy is proposed for casing and a means to reduce the casing heat pickup by up to 25 % was identified. The overall validity of the modelling approach used is difficult to validate in the engine environment, however limited data from a test engine temperature survey became available during the course of the research. By modelling this engine tip clearance control system it was shown that good agreement to the temperature distribution in the engine casing could be achieved where full surface external heat transfer coefficient boundary conditions were available.

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