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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.
31

Análise da inflamabilidade de têxteis de uniformes de aeronautas / Analysis of textile flammability of the flight crew uniform

Marcia Cristina Silva 06 September 2018 (has links)
As condições de inflamabilidade estabelecidas nas normas aeronáuticas aplicadas aos têxteis integrantes da cabine de passageiros do avião, não são requeridas para aplicação aos uniformes dos aeronautas. No entanto, uma vez que faz parte da função da tripulação, notadamente os comissários de voo, o combate de fogo a bordo, mesmo que esse tipo de acidente não seja frequente em relação à totalidade dos acidentes em geral desse setor, esse fato direcionou o presente estudo para conhecer os limites dos materiais têxteis dos uniformes dos aeronautas com relação à inflamabilidade. Deste modo, foram objetivos: determinar a inflamabilidade (velocidade de queima) de amostra de tecidos profissionais e de amostras de peças de uniformes de aeronautas; caracterizar os tecidos profissionais e os que constituem peças de uniformes de aeronautas, através de testes de: composição, gramatura, número de fio por trama e urdume, ligamento, espessura do tecido, diâmetro de fios, densidade linear e torção; calcular o diâmetro do fio e fator de cobertura e correlacionar os valores obtidos de inflamabilidade com os valores da caracterização dos tecidos e parâmetros calculados. Os experimentos foram realizados em três tecidos profissionais e em oito peças de uniformes de aeronautas de companhias diferentes, doadas para este estudo, além de entrevistas semiestruturadas e visita técnica. A interpretação dos resultados obtidos foi realizada com aplicação de testes de normalidade de dados, igualdade de variâncias, ANOVA, teste T e teste não paramétrico de Kruskall-Wallis. Os resultados encontrados no presente estudo não se enquadram nos limites preconizados pela FAR25 para que o material seja qualificado auto extinguível. O menor valor de inflamabilidade foi de 0,742±0,140 (cm/s). Este resultado trata-se da média obtida da velocidade de queima das 10 amostras ensaiadas do tecido da peça P7 (calça masculina) na direção da trama. A composição da peça é uma mistura de 50% lã e 50% poliéster com gramatura de 225,12±5,02 (g/m2), densidade linear do fio de 36,61±1,48 (tex) e torção de 598,00±45,34(torções/m). O diâmetro do fio calculado pelo modelo de Peirce foi de 0,219 mm. O maior valor de inflamabilidade foi 3,698±1,806 (cm/s). Este resultado trata-se da média obtida da velocidade de queima das 10 amostras ensaiadas do tecido da peça P5 (camisa masculina) na direção da trama. A composição da peça é uma mistura de 67% poliéster e 33% algodão com gramatura de 108,72±2,39 (g/m2), densidade linear do fio de 15,88±1,27 (tex) e torção de 991,00±45,75 (torções/m). O diâmetro do fio calculado pelo modelo de Peirce foi de 0,148 mm. Influência da direção na velocidade de queima. A análise de variância com todos os fatores, não foi validada pela análise dos resíduos., entretanto a verificação da relação entre as variáveis explicativas direção, material e ligamento com a variável resposta velocidade de queima realizada com o agrupamento por características físicas específicas, resultou em análises validadas por seus resíduos.Influência da direção na velocidade de queima para grupo material 100% CO, ligamento tela, a velocidade de queima é estatisticamente igual na direção de trama e urdume, grupo material 100% PES, ligamento sarja, a velocidade de queima é estatisticamente diferente, sendo menor na direção da trama, grupo material 100% PES, ligamento tela, a velocidade de queima é estatisticamente diferente, sendo menor na direção do urdume, grupo material 67% PES/33% CO, ligamento sarja e material 67% PES/33% CO, ligamento tela, a velocidade de queima é estatisticamente igual na direção de trama e urdume e grupo material 50% WO /50% PES, ligamento tela, a elocidade de queima é igual na direção de trama e urdume. Influência do material na velocidade de queima:grupo ligamento sarja, direção trama a velocidade de queima é estatisticamente diferente, sendo menor para a composição algodão (100%CO), grupo ligamento sarja, direção urdume a velocidade de queima é estatisticamente diferente, sendo menor para o material algodão (100%CO), grupo ligamento tela,direção trama a velocidade de queima é estatisticamente igual para os materiais 100%CO, 100%PES, 67%PES/33%CO e 50%WO/50%PES, grupo ligamento tela, direção urdume a velocidade de queima é estatisticamente igual para o material 67%PES/33%CO. Assim sugestões para estudos futuros podem levar em conta construções mais fechadas de tecidos; construção de tecidos com fibras de origem vegetal ou animal ou misturas com fibras sintéticas (com ou sem aditivação de retardantes de chamas) para agregação de funcionalidade; mudanças na modelagem das peças; e estudar alteração na gramatura dos tecidos e da torção dos seus fios constituintes / The flammability conditions laid down in the aeronautical standards applied to the textiles forming part of the passenger cabin of the aircraft. But these standards are not required for application to crew uniforms. However, since it is part of the function of the crew, notably flight attendants, the fire fighting on board, even if this type of accident is not frequent in relation to all accidents in general in this sector, this fact directed the present study to know the limits of the textile materials of the uniforms of the aeronauts with respect to the flammability. Thus, the objectives were: to determine the flammability (burning rate) of professional fabric samples and samples of aeronaut uniform pieces; characterize the professional fabrics and those that constitute parts of uniforms of aeronauts, through tests of: composition, weights, number of threads per weft and warp, weaving, fabric thickness, yarn diameter, linear density and torsion; calculate the yarn diameter and coverage factor and correlate the values of flammability obtained with the tissue characterization values and calculated parameters. The experiments were carried out in three professional fabrics and in eight pieces of uniforms of aeronauts from different companies donated for this study, in addition to semi-structured interviews and technical visits. The interpretation of the obtained results was carried out with application of tests of normality of data, equality of variances, ANOVA and response surface. The results found in the present study do not fit within the limits recommended by FAR25 for the material to be qualified self-extinguishing. The lowest flammability value was 0.742 ± 0.140 (cm/s). This result is the mean obtained from the burning rate of the 10 samples tested from the fabric of the P7 piece (male trousers) in the direction of the weft. The composition of the piece is a mixture of 50% wool and 50% polyester with a weight of 225.12 ± 5.02 (g/m2), linear yarn density of 36.61 ± 1.48 (tex) and a twist of 598.00 ± 45.34 (torsions/m). The yarn diameter calculated by the Peirce model was 0.219 mm. The highest flammability value was 3.698 ± 1.806 (cm/s). This result is the mean obtained from the burning rate of the 10 samples tested from the fabric of the piece P5 (male shirt) in the direction of the weft. The composition of the piece is a mixture of 67% polyester and 33% cotton with weights of 108.72 ± 2.39 (g/m2), linear yarn density of 15.88 ± 1.27 (tex) and twisting of 991.00 ± 45.75 (torsions/m). The wire diameter calculated by the Peirce model was 0.148 mm. The analysis of variance with all the factors was not validated by the residue analysis. However, the relationship between the explanatory variables \"direction\", \"material\" and \"ligament\" with the variable \"burning rate\" grouping by specific physical characteristics, resulted in analyzes validated by their residues. Influence of the \"direction\" on the \"burning rate\" for group \"material 100% CO, plain weave\", the burning speed is statistically equal in the direction of warp and weft, group \" material 100% PES, twill weave, burning rate is a statistically different one, being smaller in the direction of the weft, group \"material 100% PES, plain weave\", the burning speed is statistically different, being smaller in the direction of the warp, group \"material 67% PES / 33% CO, twill weave and \"material 67% PES / 33% CO, plain weave\", the burning speed is statistically equal in the direction of warp and warp and group \"material 50% WO / 50% PES, plain weave\", the speed of burn is equal in the direction of warp and warp. Influence of the material on the burning rate: group twill weave, direction weft burning rate is statistically different, being smaller to material 100% CO, group twill weave, direction warp burning rate is statiscally different, being smaller to material 100% CO, group plain weave, direction weft, burning rate is statiscally equal to material 100% CO, 100% PES, 67%/33%CO and 50%WO/50%PES, group plain weave, direction warp burning rate is statiscally equal to material 67%PES/33%CO. Thus suggestions for future studies may take into account more closed constructions of tissues; fabric construction with fibers of vegetable or animal origin or mixtures with synthetic fibers (with or without additives of flame retardants) for aggregation of functionality; changes in the modeling of parts; and to study alteration in the weight of the tissues and the torsion of their constituent yarns
32

Análise econômica financeira das alianças estratégicas entre as empresas concorrentes do tipo pseudo-concentração: o caso da aliança entre TAM e VARIG

Lucini, Juliana 02 March 2006 (has links)
Made available in DSpace on 2015-03-05T19:12:38Z (GMT). No. of bitstreams: 0 Previous issue date: 2 / Nenhuma / A estrutura e a estratégia das organizações são afetadas pela competitividade, intensificada nas últimas décadas. Devido a isso, as entidades buscam estratégias para continuarem ou se tornarem competitivas no mercado, sendo uma delas a procura por alianças estratégicas com outras organizações, atuantes ou não no mesmo mercado. Esta é a razão que motivou a realização do presente estudo, cujo objetivo foi verificar os reflexos das alianças estratégicas nos resultados econômicos das empresas que a adotam, usando como referencial o caso TAM e VARIG durante sua duração. Para tanto, realizou-se uma pesquisa documental a partir das demonstrações contábeis de VARIG e TAM para descrever possíveis impactos oriundos do compartilhamento de vôos ocorridos entre os anos de 2003 a 2005. Verificou-se que a aliança estratégica produziu resultados positivos para ambas as empresas, contudo seus efeitos benéficos puderam ser colhidos em maior proporção pela VARIG, através de uma redução de custos e despesas mais representativas / The structure and the strategy of the organizations have being affected by the international competition intensified in the last decades. Because of this concurrency the entities have being searching strategies in order to remain competitive in the market being one of them to look for partnership with other companies. This is the reason that motivated the present study which general main aim is to verify the reflexes of strategic alliances in the economic income of the companies that adopted it, using as reference the case of TAM and VARIG during their partnership. The methodology of this present study is classified as for the technical proceedings like “documental” therefore financial statements of VARIG and TAM are used to describe possible impacts from the partaking of flights occurred from 2003 until 2005. The method of research used gave us the possibility to conclude that the strategic alliance probably influenced the reduction of operational costs and expenses of both companies during the period of tim
33

ICAO's aviation security programme post 911 : a legal analysis

Jallow-Sey, Aisatou January 2003 (has links)
Unlawful interference with civil aviation has become a major concern for the world aviation community. The misuse of aircraft as a weapon of mass destruction has created new challenges. Air terrorism has moved from hijacking or unlawful seizure of aircraft to an in-flight explosion caused by sabotage and finally to September 11, 2001, to the use of a civil airplane as a weapon of destruction. / The events of September may be the biggest security challenge ever faced by the aviation industry. The impact of this tragic event on the global economy has been very harsh. The events have tended to obscure the fact that civil aviation continues to be an inherent safe mode of transport. / Great efforts are being made at the national and international levels to create a security net which is global in nature and so tight that not one further potential act of unlawful interference can slip through. However, the fact remains that, in weaving the net and designing measures with the objectives of preventing, combating and eradicating acts of terrorism involving civil aviation, it is prudent to be imaginative in assessing the threat, which could come from new directions and in new forms. / This thesis explores the implications of the 11 September 2001 events. A global strategy is initiated by ICAO and endorsed by the States, with the aim of protecting lives, restoring public confidence in air travel, and promoting the financial health of air transport. I will therefore examine the measures initiated by ICAO in response to the new challenges in aviation and which form the basis of the aviation security action plan. The perspective is that the events of 11 September have changed the world, and changed irrecoverably. Nothing will be the same for the aviation industry.
34

Deregulation of the airline industry in India an analysis of the government's policy, rationale and strategy /

Mazumdar, Arijit. January 2008 (has links)
Thesis (Ph. D.)--Miami University, Dept. of Political Science, 2008. / Title from second page of PDF document. Includes bibliographical references (p. 152-162).
35

Nodální regiony v Evropě vymezené na základě letecké dopravy

ROZKOŠNÝ, Filip January 2017 (has links)
This master´s thesis deals with the delineating of nodal regions via civil aviation data in the territory of central European states. This kind of transport has become a very popular type of spatial mobility after its deregulation and liberalization particularly thanks to its speed, cheaper fares and relative safety. Thanks to this spatial mobility of inhabitants, it is possible to delineate borders of regions according to real movements. Supposing usage of aviation data to delineate nodal regions, the airports represent their nodes. The purpose of this master´s thesis was delineating nodal regions via civil transport data in an interesting territory of Central Europe. Its western and eastern part has undergone different historical and political development which has had consequences on the aviation development level. Research input data included number of flights between central European airports for the period of 1 day. The master´s thesis is structured into 5 chapters. The first parts are: introduction and goals, theoretical part and methodology. The analytical part evaluates the whole nodal-region-delineating process and also nodal regions final hierarchical structure. Each partial part of research was depicted into a map and was also expressed by population and area. There are answers on the input hypothesis in the final part of this paper.
36

Uma proposta de solução para o aircraft recovery problem de companhias aéreas regulares de pequeno porte.

Dias, Glend Kleiser Gouveia 28 May 2015 (has links)
Submitted by Maike Costa (maiksebas@gmail.com) on 2016-04-25T13:32:58Z No. of bitstreams: 1 arquivo total.pdf: 4525999 bytes, checksum: 439ef786ba011b8d141d0b5a92537aa3 (MD5) / Made available in DSpace on 2016-04-25T13:32:58Z (GMT). No. of bitstreams: 1 arquivo total.pdf: 4525999 bytes, checksum: 439ef786ba011b8d141d0b5a92537aa3 (MD5) Previous issue date: 2015-05-28 / The airlines that operate regular ights de ne in advance the airports to be operated and the landing and takeo schedule of its aircraft. This scheduling is likely to su er interruptions causing nancial losses due to delays and/or cancellations of ights. In these situations, the airlines usually use the experience of their professionals and seek to minimize the impacts by relocating the aircraft, crew and then passengers. There is no guarantee that such method will lead to good results from an economic point of view, especially in periods of high demands of passengers. Due to this di culty, several authors have studied the Airline Recovery Problem using di erent optimization techniques. This problem is basically composed of three sub-problems: Aircraft Recovery Problem (ARP), Crew Recovery Problem (CRP) and Passenger Recovery Problem (PRP). In order to de- ne the new least-cost aircraft scheduling of a Brazilian airline (in operation interruption situations) due to delays and/or cancellations of ights, this research presents an ARP solution proposal starting from the representation of ights through a network time-space and mathematical modeling analogous to the minimum cost ow problem. To analyze the ARP, data was used from a Brazilian airline for building the time-space networks with bands of 30, 20 and 15 minutes, and 100 instances were utilized to simulate the unavailability of up to 3 aircraft on di erent nodes of such networks. The solutions based on these bands were solved via Integer Linear Programming and with average improvements of 38.24%, 40.44% and 41.15%, respectively, with respect to the trivial solutions. The band of 15 min was more appropriate because it provided a more realistic analysis of takeo s and landings events and resulted in a greater di erence, on average, between the optimal solutions and the trivial ones. Other 95 instances were tested for a time-space network with 15 min band and a spare aircraft located at the busiest airport. In this case the results were 38.68% better than the situation without a spare aircraft, but it was not conclusive because an economic feasibility analysis on the acquisition and deployment of a new aircraft in the eet must be performed. / As companhias a ereas de voos regulares possuem previamente de nidos os aeroportos que ser~ao operados, os dias e os hor arios de pouso e decolagem das suas aeronaves. E poss vel que essa programa c~ao sofra interrup c~oes e causem preju zos nanceiros devido aos atrasos e/ou cancelamentos dos voos. Nessas situa c~oes, normalmente as companhias a ereas usam a experi^encia dos seus pro ssionais e procuram minimizar os impactos realocando as aeronaves, tripulantes e em seguida os passageiros. N~ao h a garantia que esse m etodo retorne um bom resultado do ponto de vista econ^omico, sobretudo em per odos de grande demanda por passageiros. Mediante essa di culdade, diversos autores t^em estudado o Airline Recovery Problem empregando diferentes t ecnicas de otimiza c~ao. Esse problema e composto basicamente por tr^es subproblemas: Aircraft Recovery Problem (ARP), Crew Recovery Problem (CRP) e Passenger Recovery Problem (PRP). Como forma de de nir o novo sequenciamento das aeronaves de uma companhia a erea brasileira que, em situa c~oes de interrup c~oes das opera c~oes, resulte no menor custo devido aos atrasos e/ou cancelamentos dos voos, esta pesquisa apresenta uma proposta de solu c~ao do ARP a partir da representa c~ao dos voos por uma rede tempo-espa co e modelagem matem atica an aloga ao problema do uxo de custo m nimo. Para a an alise do ARP, foram utilizados dados de uma companhia a erea brasileira para a constru c~ao das redes tempo-espa co com bandas de 30, 20 e 15 minutos e empregadas 100 inst^ancias que simularam a indisponibilidade de at e 3 aeronaves em diferentes n os dessas redes. As solu c~oes baseadas nessas bandas foram resolvidas via Programa c~ao Linear Inteira e apresentaram resultados m edios, respectivamente, 38; 24%; 40; 44% e 41; 15% melhores do que as solu c~oes triviais. A banda de 15 min mostrou-se mais adequada porque possibilitou uma an alise mais realista dos eventos de pousos e decolagens e resultou numa diferen ca m edia maior entre as solu c~oes otimas e as triviais. Outras 95 inst^ancias foram testadas para uma rede tempo-espa co com banda de 15 min e aeronave reserva localizada no aeroporto de maior movimento. O resultado foi 38; 68% melhor do que a situa c~ao sem aeronave reserva, mas n~ao conclusivo por ser necess aria uma an alise de viabilidade econ^omica sobre a aquisi c~ao e disponibiliza c~ao de uma nova aeronave na frota.
37

ICAO's aviation security programme post 911 : a legal analysis

Jallow-Sey, Aisatou January 2003 (has links)
No description available.
38

Deregulation of the Airline Industry in India: An Analysis of the Government's Policy, Rationale and Strategy

Mazumdar, Arijit 24 July 2008 (has links)
No description available.
39

Le secteur de l’aviation et les règles de concurrence de l’Union européenne : étude des comportements et des rapprochements d’entreprises / The aviation sector and the European Union's competition rules : Study on conducts and rapprochements of undertakings

Vougioukas, Dimitrios 10 February 2012 (has links)
L’application des règles de concurrence de l’Union européenne au secteur de l’aviation présente un caractère spécial. Les rapprochements des compagnies aériennes sous formes d’alliances ou concentrations sont à première vue indispensables, afin de garantir leur viabilité et mieux desservir les besoins des voyageurs. La pression concurrentielle exercée par les différents moyens de transports et la globalisation des échanges conduisent vers cette voie. Or, la consolidation du marché aérien peut avoir des conséquences néfastes au détriment des consommateurs. Structure oligopolistique, organisation des gros opérateurs en réseaux (hub-and-spoke system), insuffisance des infrastructures, coûts énormes d’exploitation ainsi que protectionnisme au niveau international, constituent des barrières considérables à l’entrée de nouveaux concurrents et peuvent conduire à des pratiques abusives. La transparence tarifaire et les accords de coopération peuvent favoriser les cartels entre transporteurs aériens. La Commission évalue la position des parties et les risques à la concurrence sur des liaisons déterminées (paires de villes). Cette méthode de délimitation du marché pertinent au transport aérien suscite une polémique de la part notamment des compagnies aériennes qui soutiennent une approche fondée sur la concurrence entre réseaux. Ce débat, montre l’évolution du secteur de l’aviation et la nécessité de prendre toujours en compte les nouvelles données. Le maintien d’une concurrence efficace au secteur de l’aviation n’est pas un objectif en soi, mais un instrument de la politique européenne pour la création du « ciel unique européen ». L’intervention des autorités de l’Union européenne au secteur de l’aviation ne se limite pas à une application rigoureuse des règles de concurrence mais vise à éliminer préalablement les phénomènes anticoncurrentiels par l’adoption d’un cadre législatif. / The application of European Union’s competition rules to the aviation sector presents a special character. The rapprochement of air companies either by the formation of alliances or mergers seem to be necessary. Indeed, it can guarantee the existence of a company as well as it serves the needs of travellers. The competitive pressure exercised by the different existing means of transportation and the globalisation of exchanges lead to this behaviour. But this consolidation of the air market can have harmful consequences for consumers. Oligopolistic structures, the hub-and-spoke system, insufficiency of infrastructures, enormous costs of exploitation along with protectionism at an international level, constitute considerable barriers for new competitors and could lead to abusive practices. Tariff transparency and cooperative agreements can furtherer cartels in between air transporters. The Commission assesses the position of the parties and competitive risks on specific routes (city pairs). This method of delimitation of the market for air transport has created a polemic, especially from the airline companies supporting an approach based on competition between networks. This debate shows the evolution of the aviation sector and the necessity of always taking into consideration new data. The upholding of an efficient competition system within the aviation sector is not an objective in itself, but means of European politic for the creation of a “Single European Sky”. The intervention of European authorities within the aviation sector is not limited to a rigorous application of competition rules but aims first at eliminating anticompetitive phenomenon by adopting a legislative framework.
40

Le contrôle de la connectivité aérienne, un outil de puissance sur la scène internationale : les stratégies de développement d’Emirates Airline, Etihad Airways, Qatar Airways et Turkish Airlines / The control of air connectivity, a tool of power on the international stage : the development strategies of Emirates Airline, Etihad Airways, Qatar Airways and Turkish Airlines

Lebel, Julien 02 July 2018 (has links)
Le développement de puissantes compagnies aériennes bénéficiant d’un soutien évident d’acteurs politiques qui ont (re)lancé leurs activités vient poser d’importants défis pour le secteur aérien international. De fait, de nombreuses entités politiques perçoivent le transport aérien comme un outil indispensable afin de promouvoir leurs intérêts et s’imposer davantage sur la scène internationale. Les cas des émirats de Dubaï, d’Abu Dhabi et du Qatar, ainsi que de la Turquie illustrent pleinement la façon dont des acteurs politiques utilisent le développement d’une compagnie aérienne localement basée en fonction d’objectifs qui leur sont propres. La croissance inédite d’Emirates Airline, Etihad Airways, Qatar Airways et Turkish Airlines vient toutefois bouleverser l’évolution de la connectivité aérienne mondiale, tandis que les nombreux acteurs de l’aérien peinent à s’accorder sur la mise en œuvre d’un cadre de portée internationale censé garantir l’existence d’une « concurrence loyale » entre les transporteurs, sur fond d’intérêts divergents. Le contrôle de la connectivité constitue en effet un instrument de soft power qui vient renforcer la position des acteurs qui l’utilisent, tout en créant des liens de/d’(inter)dépendance croissants. Les autorités politiques adoptent toutefois des approches différenciées afin de développer leur soft power, tandis que l’Union européenne s’avère être, pour l’heure, en retrait d’une telle dynamique. / The growth of strong airlines benefiting from a large support of political stakeholders who have (re)launched their activities is leading to important challenges for the international air transport sector. Numerous political entities perceive aviation as an essential tool to promote their interests and to gain more international recognition. The cases of the emirates of Dubai, Abu Dhabi and Qatar, but also Turkey are fully showing how political stakeholders use the development of a locally based airline according to their own goals. The large growth of Emirates Airline, Etihad Airways, Qatar Airways and Turkish Airlines is disrupting the air connectivity evolution at a worldwide scale, while numerous aviation stakeholders do not reach to agree on an international framework aiming to safeguard a “fair competition” between air carriers, in a context of differing interests. Thus, the control of air connectivity forms a soft power instrument strengthening the position of stakeholders who are using it while creating in the meantime growing (inter)dependence links. Political authorities adopt however differentiated approaches in order to expand their soft power, whereas the European Union is, for now, staying away of such a dynamic.

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