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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

Modelagem integrada para a programação de voos e a alocação de frotas: abordagens baseadas em programação linear inteira e na meta-heurística colônia de formigas. / An integrated model for flight scheduling and fleet assignment based on integer linear programming and on ant colony meta-heuristic.

Daniel Jorge Caetano 12 May 2011 (has links)
Este trabalho propõe modelos matemáticos e heurísticas para a definição da malha de voos de uma empresa aérea, como parte de seu planejamento operacional, visando à maior eficiência de operação frente às restrições relacionadas aos aeroportos, a equipamentos e à demanda. Em especial, é proposta uma função objetivo, baseada no momento de transporte, para a modelagem integrada dos problemas de Programação de Voos e Alocação de Frotas que inclui elementos específicos para a consideração de slots de pouso e decolagem. A abordagem tem aplicação especialmente relevante no âmbito de empresas aéreas de pequeno e médio porte atuando em mercados regionais, cuja malha é composta principalmente por voos de curta duração, em geral operando com aeronaves de pequeno e médio porte. Nestas condições, tais empresas trabalham com margens de lucro limitadas e, portanto, podem-se beneficiar sensivelmente da definição de uma malha mais eficiente e eficaz. Os modelos desenvolvidos, baseados em programação linear inteira e na meta-heurística Ant Colony Optimization, foram aplicados com sucesso ao caso de uma empresa aérea regional, com atuação no mercado brasileiro, possibilitando a definição de malhas alternativas, bem como fornecendo subsídos para a avaliação dos impactos na malha oriundos da utilização de novas aeronaves. / This research proposes mathematical models and heuristics to define the flight mesh of an airline, as part of its operational planning, considering restrictions related to airports, equipment and demand. In particular, an objective function is formulated, based on transport momentum, proposed for the integrated modeling of Flight Scheduling and Fleet Assignment problems that includes specific elements to consider landing and takeoff slots at airports. The approach is especially relevant for small and medium airlines operating in regional markets, with short-haul flights, in general operating with small or medium size aircraft. Accordingly, these companies work with limited profit margins, and, therefore, they can take great benefit from a more efficient and effective flight mesh. The models proposed, based on integer linear programming and on the Ant Colony Optimization meta-heuristic, were successfully applied to the case of a regional airline with operations in Brazil, enabling the definition of mesh alternatives as well as providing information for the assessment of impacts in its flight network arising from the utilization of new aircraft.
32

Market orientation and the performance of airports in Europe’s peripheral areas

Halpern, Nigel 12 1900 (has links)
As a consequence of deregulation in the airline industry, market forces rather than public service considerations increasingly dictate services to and from airports in Europe’s peripheral areas. The new market advocates market-driven management practices as a means of satisfying airline customers and implies that airports that adopt a more marketorientated approach than their rivals will perform better. This study investigates the theoretical foundations of a market orientation, which can be defined as the organisationwide generation, dissemination and response to market intelligence. The main aim of this study is to examine the relationship between market orientation and the performance of airports in Europe’s peripheral areas. The research methodology was implemented using a questionnaire-based survey that was administered to the managers of 217 airports in 17 different countries. Usable responses from 86 airports were received and analysed. The findings of this study suggest that airports wishing to outperform competitors can do so by adopting a market orientation and should seek to continually monitor and improve the way in which they gather, disseminate and respond to market intelligence. This will be particularly effective when market turbulence is high and/or when the focus of the airport is on developing leisure services. In addition, market orientation was found to have a positive effect on performance because it means that airports are more likely to be innovative in their approach to marketing. This means that airport managers should try to develop a market-orientated culture with innovative marketing practices in mind, and visa versa. The fact that independently-owned airports have significantly higher levels of market orientation than regionally-owned or nationally-owned airports suggests that independent ownership is more conducive to the development of a market orientation. The findings of this study do have a number of limitations, the most notable being that they are restricted to airports in Europe’s peripheral areas. It is recommended that future research should be conducted on airports worldwide in order to investigate differences between a wider range of airport types and geographical regions. In addition, the findings of this study suggest that a stakeholder orientation is important for airports seeking to improve their performance, especially smaller airports that are publicly-owned. It is recommended that future studies should investigate antecedents to and consequences of a stakeholder orientation. Future studies should also investigate whether a stakeholder orientation has a greater effect on performance than a market orientation does, and whether the two types of orientation complement each other.
33

Policy development framework for aviation strategic planning in developing countries

Itani, Nadine M. 02 1900 (has links)
There exists no predefined framework for aviation policy making and development. While aviation policy planning in most developed countries comes as a result of institutional and industry coordination and is embedded within other national policies addressing the welfare and growth of the country, it is found that in many cases in less developed countries (LDCs), aviation policy planning is often influenced by political pressures and the interests of fund donors. The complexity of this situation in the developing countries results in aviation plans that represent stand alone studies and attempt to find solutions to specific problems rather than comprehensive aviation plans which fit well the country‘s competitiveness profile and are properly coordinated with other national policies for achieving medium and long-term objectives. This study provides a three-stage policy development framework for aviation strategic planning based on situational analysis and performance benchmarking practices in order to assemble policy elements and produce a best-fit aviation strategy. The framework builds on study results that indicate an association between air transport sector performance and aviation policy strategies, arguing that it is not sufficient to simply describe performance but also to be able to assess it and understand how policymakers can use strategic planning tools to affect the air transport industry efficiency levels. This can be achieved by recognizing the level of the country‘s stage of development and working on enhancing the policy elements that produce better output and induce more contributions by aviation to the national economic development and connectivity levels. The proposed aviation policy development framework is systematic and continuous. It helps policymakers in LDC to manage uncertainty in complex situations by allowing them to defend, correct and re-examine the policy actions based on a forward thinking approach which incorporates the contingency elements of the policy and tracks the developments that can affect the odds of its success. The framework‘s elements and its flow of process are explained by providing an illustrative example applied to the Hashemite Kingdom of Jordan.
34

Οι στρατηγικές ανάπτυξης και επέκτασης των αεροπορικών εταιριών χαμηλού κόστους και ο ελληνικός τουρισμός

Αβραμόπουλος, Αβραάμ 24 October 2012 (has links)
Η παρούσα διδακτορική διατριβή προσεγγίζει το θέμα του εισερχόμενου τουρισμού στην Ελλάδα υπό το πρίσμα των αερομεταφορών και ειδικότερα μέσω των στρατηγικών επιλογών μιας ιδιότυπης μορφής αερομεταφορέων, όπως είναι οι αεροπορικές εταιρίες χαμηλού κόστους (Low Cost Carriers). Η ανάπτυξη των εταιριών αυτών αποτελεί μία από τις σημαντικότερες εξελίξεις στο χώρο των αερομεταφορών παγκοσμίως. Αυτός ο «νέος» τύπος αερομεταφορέων έχει αναταράξει σε βάθος και αποφασιστικά το καθεστώς των αερομεταφορών γενικά και συγκεκριμένα των αποκαλούμενων παραδοσιακών αερομεταφορέων δικτύων με την εισαγωγή ενός επιχειρησιακού μοντέλου χαμηλού κόστους, το οποίο επιτρέπει σε αυτές τις αερογραμμές να προσφέρουν οικονομικά εισιτήρια στους πελάτες τους. Οι αεροπορικές εταιρίες χαμηλού κόστους (LCCs) αποτελούν μια σημαντική διάσταση στις σύγχρονες στρατηγικές ανάπτυξης και ανταγωνισμού στον τομέα των αερομεταφορών διεθνώς. Η διατριβή εστιάζει στον καθορισμό των προσδιοριστικών παραγόντων στρατηγικής ανάπτυξης των LCCs καθώς και στις επιδράσεις αυτών των στρατηγικών επιλογών στον ελληνικό τουρισμό. Ο σκοπός της διατριβής είναι να περιγράψει το επιχειρησιακό τους μοντέλο και να καταγράψει τις στρατηγικές που αυτές ακολουθούν. Αναφορικά με την μεθοδολογική προσέγγιση, επιλέχθηκε η έρευνα περιπτωσιολογικής μελέτης για την διερεύνηση των στρατηγικών των αερομεταφορέων χαμηλού κόστους και των πιθανόν επιδράσεών τους στον εισερχόμενο τουρισμό στην Ελλάδα. Η επιλογή αυτή εξαρτήθηκε σε μεγάλο βαθμό από την φύση του αντικειμένου και των ερωτημάτων που τέθηκαν λαμβανομένων υπόψη των περιορισμών, όσον αφορά στα λιγοστά και κατακερματισμένα διαθέσιμα στατιστικά στοιχεία σχετικά με τους αερομεταφορείς χαμηλού κόστους, σε ό,τι αφορά την Ελλάδα τουλάχιστον και τις αεροπορικές τους συνδέσεις με αυτήν. Συμπερασματικά θα λέγαμε, ότι οι αερομεταφορές αποτελούν αναπόσπαστο τμήμα του τουριστικού προϊόντος και ότι τα τελευταία χρόνια επικρατεί αισιοδοξία αναφορικά με τη αεροπορική διασύνδεση των κομβικών και περιφερειακών αεροδρομίων της Ελλάδας με ευρωπαϊκούς προορισμούς. Η είσοδος νέων αεροπορικών εταιριών χαμηλού κόστους, στον ΔΑΑ που συνδέουν απευθείας διάφορους ευρωπαϊκούς προορισμούς με την Αθήνα καθώς και οι εξελίξεις στην ανατολική Ευρώπη, εξαιτίας της ένταξης νέων χωρών στην Ευρωπαϊκή Ένωση δημιουργεί νέα δεδομένα στις αερομεταφορές και στην σύνδεση της Αθήνας, αλλά και των περιφερειακών αερολιμένων με αεροδρόμια της κεντρικής και ανατολικής Ευρώπης. Οι αεροπορικές εταιρίες ναυλωμένων πτήσεων, οι οποίες παραδοσιακά είχαν συνδεθεί με την ανάπτυξη του ελληνικού τουρισμού προσπάθησαν να αναθεωρήσουν το επιχειρηματικό τους μοντέλο, ώστε να ανταγωνιστούν τις εταιρίες χαμηλού κόστους. Η Ελλάδα θεωρείται μια αγορά υψηλού κόστους λόγω των διαφόρων επιβαρύνσεων στα τέλη των αερομεταφορών. Καθώς όμως χρειάζεται να ανταγωνιστεί και με άλλες παραδοσιακές αγορές, η πολιτεία χρειάζεται να δράσει σε συνεργασία με όλους τους εμπλεκόμενους φορείς ώστε να υποστηρίξει τις στρατηγικές επιλογές επέκτασης των LCCs και μέσα από μακροπρόθεσμες πολιτικές να διατηρήσει και να ενισχύσει την προσέλευση των LCCs σε ελληνικά αεροδρόμια. / This doctoral dissertation deals with inbound tourism to Greece within the context of air transport and specifically through the strategic choices of a singular form of air transport, such as low-cost carriers. The growth of these companies is one of the most significant global developments in the air transport industry. This “new” type of air transport has thoroughly and decisively stirred up the status quo in air transport and specifically, the so-called traditional air transport networks, through the introduction of the low-cost model that permits these airlines to offer economically competitive tickets to their customers. The low-cost carriers (LCCs) are a significant dimension in the modern development and competition strategies of the air transport industry. The dissertation focuses upon defining the determinant factors in the development strategies of the LCCs, as well as the influence of these strategic choices upon Greek tourism. The dissertation’s purpose is to describe their business model and to record the strategies that they follow. The case study research approach was selected in relation to the methodology in order to investigate the strategies of the low-cost carriers and their potential influences on inbound tourism to Greece. This choice is largely dependent upon the nature of the objective and the questions that are raised, which takes into consideration the restrictions relating to the scarce and fragmented statistics that are available on the low-cost carriers, at least in relation to Greece and their air connections to it. In conclusion, we could say that air transport is an integral part of the tourist product and that optimism has prevailed in recent years on the interconnection by air of the central and regional airports in Greece with European destinations. The entry by new airlines into AIA (Athens International Airport), which directly connect the European destinations to Athens, as well as the developments in Eastern Europe, through the incorporation of many nations into the European Union, has created a new status quo for air transport and the connection of Athens to the Central and Eastern European airports. The chartered flight airlines that were traditionally connected to the growth of Greek tourism have attempted to review their business model, so as to compete with the low-cost carriers. Greece is considered to be a high-cost market, due to the various charges on the air transport duties. The State needs to act in collaboration with all authorities involved in order to retain and support the presence of LCCs at Greek airports, in addition to the need to also compete with the other traditional markets.
35

LETECKÁ DOPRAVA JAKO FAKTOR GLOBALIZAČNÍCH PROCESŮ: PŘÍPADOVÁ STUDIE INDIE

PRENER, Jan January 2018 (has links)
Aviation has been affected by many important changes over the last decades, the structure of these changes comes from the amassing globalization. Similarly, the aviation changes the geographical organization of the whole world in terms of the genesis, selection and establishment of new economic, social, political, cultural and many other relations. Considering these facts and other aspects, transforms aviation into the tight indicator of globalization. Due to the reasons, the thesis focuses on the identification, analysis, description, and explanation of processes that take part in the worldwide organization of aviation. The example of India is chosen as the most appropriate because of the continuing development of its economic status. Dynamic disposition of transforming India leads the country into both the hypothetical and real point of intersection of many socio-economic changes. India is also considered a candidate for the primacy of the world-class aviation status. Given these facts, the main task of the thesis is to establish a specific study through statistical and spatial methods. The study should determine how much India is involved in global aviation, included participated changes.
36

Market orientation and the performance of airports in Europe's peripheral areas

Halpern, Nigel January 2006 (has links)
As a consequence of deregulation in the airline industry, market forces rather than public service considerations increasingly dictate services to and from airports in Europe’s peripheral areas. The new market advocates market-driven management practices as a means of satisfying airline customers and implies that airports that adopt a more marketorientated approach than their rivals will perform better. This study investigates the theoretical foundations of a market orientation, which can be defined as the organisationwide generation, dissemination and response to market intelligence. The main aim of this study is to examine the relationship between market orientation and the performance of airports in Europe’s peripheral areas. The research methodology was implemented using a questionnaire-based survey that was administered to the managers of 217 airports in 17 different countries. Usable responses from 86 airports were received and analysed. The findings of this study suggest that airports wishing to outperform competitors can do so by adopting a market orientation and should seek to continually monitor and improve the way in which they gather, disseminate and respond to market intelligence. This will be particularly effective when market turbulence is high and/or when the focus of the airport is on developing leisure services. In addition, market orientation was found to have a positive effect on performance because it means that airports are more likely to be innovative in their approach to marketing. This means that airport managers should try to develop a market-orientated culture with innovative marketing practices in mind, and visa versa. The fact that independently-owned airports have significantly higher levels of market orientation than regionally-owned or nationally-owned airports suggests that independent ownership is more conducive to the development of a market orientation. The findings of this study do have a number of limitations, the most notable being that they are restricted to airports in Europe’s peripheral areas. It is recommended that future research should be conducted on airports worldwide in order to investigate differences between a wider range of airport types and geographical regions. In addition, the findings of this study suggest that a stakeholder orientation is important for airports seeking to improve their performance, especially smaller airports that are publicly-owned. It is recommended that future studies should investigate antecedents to and consequences of a stakeholder orientation. Future studies should also investigate whether a stakeholder orientation has a greater effect on performance than a market orientation does, and whether the two types of orientation complement each other.
37

Estudo do comportamento de um detector de radiação passivo para fins aeronáuticos utilizando o método Monte Carlo / Performance study of a passive radiation detector for aviation purpose using the Monte carlo method

MENCARINI, LEONARDO de H. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:42:26Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:01:36Z (GMT). No. of bitstreams: 0 / Dissertação (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
38

Estudo do comportamento de um detector de radiação passivo para fins aeronáuticos utilizando o método Monte Carlo / Performance study of a passive radiation detector for aviation purpose using the Monte carlo method

MENCARINI, LEONARDO de H. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:42:26Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:01:36Z (GMT). No. of bitstreams: 0 / Profissionais da área aeronáutica, como pilotos e comissários de bordo, são submetidos a doses de radiação de origem cósmica, que podem ser maiores do que as doses médias dos trabalhadores da indústria nuclear. A diversidade de partículas de altas energias presentes no campo de radiação a bordo das aeronaves torna complexa a mensuração da dose e requer cuidados especiais em relação aos sistemas de dosimetria a serem empregados nesta área. A Força Aérea Brasileira, por meio de seu Instituto de Estudos Avançados (IEAv /DCTA), em conjunto com o Instituto de Pesquisas Energéticas e Nucleares (IPEN / CNEN -SP) vem estudando o assunto desde 2008. Um protótipo de detector de radiação passivo para medições em aeronaves foi previamente construído e testado em condições de voo e de laboratório. O detector é capaz de medir a grandeza dosimétrica conhecida como dose absorvida (usando dosímetros passivos), que serão posteriormente correlacionados ao equivalente de dose ambiente e à dose efetiva recebidos por profissionais da área aeronáutica. Neste contexto, uma abordagem teórica por meio de simulações Monte Carlo com os códigos computacionais MCNP5 e MCNPX, foi usada para modelar e caracterizar a resposta do detector em determinadas condições experimentais. Este trabalho apresenta os resultados preliminares da modelagem computacional, com ênfase especial na comparação entre a grandeza fundamental dose absorvida (mensurada e simulada) e sua relação com o equivalente de dose ambiente e dose efetiva para este detector. / Dissertação (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
39

Instrumento de apoio ao planejamento da inovação em combustíveis ecoeficientes para a aviação / Support of the innovation planning in eco-efficient aviation fuel

Silva, Jéssica Traguetto 17 November 2015 (has links)
Submitted by Luciana Ferreira (lucgeral@gmail.com) on 2016-02-01T11:37:27Z No. of bitstreams: 2 Dissertação - Jéssica Traguetto Silva - 2015.pdf: 2171936 bytes, checksum: e643c2108827dd6c78fad5f3d248b88c (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2016-02-01T11:39:29Z (GMT) No. of bitstreams: 2 Dissertação - Jéssica Traguetto Silva - 2015.pdf: 2171936 bytes, checksum: e643c2108827dd6c78fad5f3d248b88c (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2016-02-01T11:39:29Z (GMT). No. of bitstreams: 2 Dissertação - Jéssica Traguetto Silva - 2015.pdf: 2171936 bytes, checksum: e643c2108827dd6c78fad5f3d248b88c (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2015-11-17 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / It is anticipated that the next twenty years the air transport will present an increase of almost double the growth rate of world GDP. It is projected that while GDP will grow 3.2%, air and passenger traffic present the average growth 5%. This accelerated expansion of the sector has caused some negative consequences, such as the significant increase in carbon dioxide emissions. The aviation industry has already committed in changing this scenario and the target is to halve CO2 emissions by 2050. To achieve this goal, it is necessary to planning ecoefficient aviation fuel that minimize negative effects such as in the case of substitution of fossil fuels by fuel extracted from renewable resources, which allows the reduction by 80% of CO2 emissions. The identification of alternatives that allow this substitution has been carried out in different research groups, however, it is clear that the planning of innovation has been carried out not integrated manner and also the related literature neglects elements related to innovation management, especially planjeamento . In this sense, this study seeks to fill this theoretical gap and seeks to contribute to this issue by proposing a theoretical method that guides innovation in this sector. From characteristics of tools to support the outstanding innovation of planning in the literature was drawn up the proposed planning method, identified as MEPICE. To check if the method would be considered applicable to the context to which it is addressed, the planning of innovation in eco-efficient fuel, used the Delphi methodology. The result demonstrates the feasibility of MEPICE and suggestions of experts were used in order to improve it. / Prevê-se que nos próximos vinte anos o transporte aéreo apresentará um crescimento de quase o dobro da taxa de crescimento do PIB mundial. Projeta-se que enquanto nesse período o PIB crescerá 3,2%, o tráfego aéreo e de passageiros apresentará o crescimento médio de 5%. Essa expansão acelerada do setor tem causado algumas consequências negativas, como o aumento significativo das emissões de dióxido de carbono. A indústria da aviação já se comprometeu na mudança desse cenário e a meta é reduzir pela metade as emissões de CO2 até 2050. Para o alcance dessa meta, torna-se necessário o planejamento de combustíveis ecoeficientes para a aviação que minimizem os impactos negativos, como no caso da substituição de combustíveis fósseis por combustível extraídos a partir de recursos renováveis, o que permite a redução em até 80% das emissões de CO2. A identificação de alternativas que permitam essa substituição tem sido realizada em diferentes grupos de pesquisa, porém, percebe-se que o planejamento das inovações tem sido realizado de modo não integrado e ainda a literatura relacionada negligencia elementos relacionados à gestão da inovação, especialmente ao planjeamento. Nesse sentido, o presente estudo busca preencher essa lacuna teórica e busca contribuir com esse tema através da proposição de um método teórico que oriente a inovação nesse setor. A partir de características de instrumentos de apoio ao planejamento da inovação de destaque na literatura elaborou-se o método de planejamento proposto, identificado como MEPICE. Para a verificação se o método seria considerado aplicável ao contexto a que se destina, o de planejamento da inovação em combustíveis ecoeficientes, utilizou-se a metodologia Delphi. O resultado obtido demonstra a viabilidade do MEPICE e as sugestões dos especialistas foram utilizadas no sentido de aprimorá-lo.
40

A expansão territorial de rede hoteleira e o aeroporto internacional de São Paulo/Guarulhos - A (re)produção de centralidades no município de Guarulhos (SP) / The Territorial Expansion the Hotel Chain and the Airport International of Sao Paulo/Guarulhos - The (Re) Production of Centralities in Guarulhos (SP).

Alexandre Magno Pires 06 March 2014 (has links)
A presente pesquisa visa mostrar como a instalação e edificação de um empreendimento urbano, no caso o Aeroporto Internacional de São Paulo/Guarulhos - Governador André Franco Montoro, inaugurado em 1985, induziu a expansão territorial da rede hoteleira e possibiltou a (re) produção de centralidades no Município de Guarulhos. Analisado a partir da Capital São Paulo e no espaço urbano de Guarulhos, como estas transformações espaciais e estruturais implicam no surgimento e expansão dos hotéis, bem como, a concentração de serviços atrelados ao funcionamento e manutenção destes equipamentos, fomentam a (re) produção de centralidades no município de Guarulhos / The present study aims show how the installation and construction of an enterprise urban, on case international airport of Sao Paulo/Guarulhos - governor Andre Franco Montoro, opened in 1985, induced expansion territorial network hotel and enabled the (re) production of centralities in Guarulhos (SP) Passed from the Capital - Sao Paulo and urban space in Guarulhos, how these transformations imply the emergence and expansion of hotels, and the concentrations of services linked to the operation and maintenance of such equipament, foster the (re) production of centralities in the county of Guarulhos

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