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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.
231

Estimativas do efeito da taxa de despacho de bagagem / Estimativas do efeito da taxa de despacho de bagagem sobre tarifas aéreas

Resende, Bruno César Mariano 28 March 2018 (has links)
Submitted by Bruno César Mariano Resende (bcmresende@gmail.com) on 2018-09-20T17:46:26Z No. of bitstreams: 1 Dissertacao_BrunoResende.pdf: 608696 bytes, checksum: d636a937718a3a2333998aeac725f17c (MD5) / Approved for entry into archive by Janete de Oliveira Feitosa (janete.feitosa@fgv.br) on 2018-10-11T14:13:10Z (GMT) No. of bitstreams: 1 Dissertacao_BrunoResende.pdf: 608696 bytes, checksum: d636a937718a3a2333998aeac725f17c (MD5) / Made available in DSpace on 2018-10-29T12:21:22Z (GMT). No. of bitstreams: 1 Dissertacao_BrunoResende.pdf: 608696 bytes, checksum: d636a937718a3a2333998aeac725f17c (MD5) Previous issue date: 2018-03-28 / Esta dissertação tem como principal objetivo estudar o impacto da cobrança de taxa de bagagem sobre o nível de preço das passagens aéreas e o comportamento do consumidor. Utilizando dados sobre o preço de passagens aéreas vendidas divulgados nos Microdados da ANAC, estimo regressões sob diferentes especificações de efeitos fixos e variáveis de controle para avaliar o impacto da cobrança da taxa de bagagem sobre tarifas. Na especificação que julgo mais adequada para lidar com possíveis endogeneidades, encontro uma redução média de R$ 14,85 no preço da tarifa. Em seguida, realizo estimativas da demanda por passagens aéreas em um modelo logit e do efeito da taxa de bagagem sobre a valoração do consumidor / The main objective of this dissertation is to study the impact of baggage fees adoption on the level of airline tickets prices and the behavior of consumers. Using microdata on the price of airline tickets published by ANAC (the Brazilian airlines regulator), I estimate regressions under different specifications of fixed effects and covariates to evaluate the impact of baggage fee adoption on prices. In the specification that I argue as the most appropriate to avoid possible endogeneities, I find an average reduction of R$14.85 in the price of airline tickets. Next, I develop estimates of the demand for airline tickets under a logit model and the effect of baggage fee adoption on consumer’s utility.
232

Modelagem integrada do problema de programação de tripulantes de aeronaves. / Integrated modeling of the airline crew scheduling problem.

Wagner de Paula Gomes 20 January 2014 (has links)
Esta pesquisa trata o Problema de Programação de Tripulantes (PPT), presente no planejamento operacional das empresas aéreas. O principal objetivo do PPT é atribuir o conjunto de tripulantes requeridos para a operação dos voos de uma malha aérea de maneira a minimizar o custo total da tripulação, levando em conta a legislação pertinente e a satisfação dos tripulantes. O PPT é normalmente dividido na literatura em dois subproblemas independentes, modelados e resolvidos sequencialmente: Problema de Determinação de Viagens (PDV) e Problema de Atribuição de Escalas (PAE). Esta decomposição não incorpora os atributos (disponibilidade, qualificação, senioridade e preferências individuais) dos tripulantes de forma global, o que não permite uma estimativa real de custo e afeta a qualidade da solução final. O estado da arte envolve a solução integrada do PPT, eliminando a necessidade de se resolver inicialmente o PDV e permitindo a obtenção de uma solução mais realista. O PPT, no entanto, é de natureza combinatória. Assim sendo, esta pesquisa propõe e explora modelos baseados em programação linear inteira e em heurísticas para a solução integrada do PPT. Essas heurísticas incorporam fundamentos da meta-heurística GRASP, da heurística de economias de Clarke e Wright e da heurística day-by-day. Os modelos foram testados com sucesso para a solução de instâncias baseadas na malha real de três empresas aéreas brasileiras. / This doctoral research treats the Crew Scheduling Problem (CSP), as part of the airlines operational planning. The CSP consists of optimally assigning the required crew members to planned flights, in such a way that it minimizes the total cost of the aircrew, taking into consideration the proper legislation and the satisfaction of the crew members. The CSP is usually divided into two independent subproblems, modeled and solved sequentially: Crew Pairing Problem (CPP) and Crew Rostering Problem (CRP). This decomposition does not incorporate all the crew members attributes (availability, qualification, seniority and individual preferences), which does not lead to a real cost estimate and affects the quality of the final solution. The state of the art involves the integrated solution of CSP, without solving the CPP at first and providing a more realistic solution. The CSP, however, has a combinatorial nature. This research proposes and explores models based on integer linear programming and on heuristics to solve the CSP in an integrated way. These heuristics incorporate GRASP metaheuristic, Clarke and Wright savings heuristic and day-by-day heuristic. The models were successfully tested to solve instances related to the networks of three Brazilian airlines.
233

Changes to the marketing strategy of the airline industry in Europe due to the proliferation of low-cost airlines in Europe / Změny v marketingové strategii leteckých společností v Evropě způsobené růstem nízkonákladových leteckých společností v Evropě

Keprta, Jan January 2015 (has links)
The aim of this thesis is to analyze the changes to marketing strategy of airline companies in Europe due the proliferation of low-cost carriers in Europe. The thesis is divided into three parts. In the theoretical part the marketing strategy framework is established by reviewing the latest literature on marketing theory and its application to the airline industry. The second chapter provides the historical background and shows the specifics of the airline industry in order to determine when the proliferation of low-cost carriers in Europe occurred. It also analyzes the impact the proliferation had on the business operations of the network carriers by looking at the changes to different elements of the marketing mix. Finally the third chapter summarizes the authors research on consumer behavior in the airline industry. The research was conducted through a quantitative questionnaire and it investigates consumers perception of price and brand awareness.
234

Financial Analysis and Company Valuation of Lufthansa Group / Finanční Analýza a Ohodnocení Společnosti Lufthansa

Hamacek, Michaela Maria January 2015 (has links)
The aim of the thesis is to provide investors and other stakeholders with an approach how to calculate the fair value of a company and its stocks to make an investment decision. As stock market prices are influenced by many events, they rarely reflect the true underlying value of the company. The company investigated in this thesis is the German airline company Lufthansa. A strategic, a financial and a ratio analysis are performed before the fair value is assessed using the discounted cash flow method under three future scenarios. The analyses revealed a possible undervaluation of the company, which led to a buy recommendation for shares of Lufthansa.
235

Regional airline qualifications: A study in the marketability of higher education graduates.

Fullingim, James Fred 12 1900 (has links)
The recent emergence and growth of the regional airlines in the United States has placed a strain on the supply of pilots that are needed for staffing scheduled flights. This present pilot shortage is presenting challenges for 2-year colleges and 4-year universities with aviation programs to produce more pilot graduates in less time to meet the staffing demands made by the regional airlines. With this shortage, the pressing issues of how to train and hire qualified pilots to fly technologically advanced regional airline jet aircraft have forced the industry to demand more aviation skills from a shrinking market of aviation pilot candidates. Colleges and universities with aviation programs have been forced to compete with outside private aviation schools on a larger scale in the training of collegiate students for airline employment opportunities. The primary purpose of this study was to expose any inadequacies in the higher-education aviation curricula and to propose changes needed to better qualify aviation students in the hiring process at regional air carriers. This study concentrated on the principle that higher education is necessary for advancing a pilot's aptitudes and abilities to perform the highly technical tasks of a professional pilot in a regional airline environment. The avenues of obtaining aviation experience along with flight certificates and ratings in an academic environment from 2-year colleges and 4-year universities with aviation programs is examined, along with qualifying these schools with the criteria regional airlines expects from new pilots hired. A survey was used to poll the pilots from two regional airlines that were based in Texas. By analyzing the responses from the returned surveys, the quality of training that existed in higher education aviation programs was revealed. The study confirmed the value of advising a path of higher education for students embarking on an aviation career as a pilot for a regional airline. The study concluded that 2-year colleges and 4-year universities with aviation programs are meeting the present demands made by the regional airlines.
236

Výběr vhodného typu letounu pro dálkové tratě / Selection of Suitable Long-range Aircraft Type

Kedzior, Jakub January 2008 (has links)
The objectiv of my work is determined on the basis accessible information from airline and producers acceptable long-range aircreft type. The book of aeronautics, aircraft, aeronautice magazíne and internet webside helped me to write this thesis.
237

Výcvik dopravních pilotů / Airline pilot training

Müller, David January 2011 (has links)
This thesis is intended to highlight the difficulty and different methods of training airline pilots. It can also serve as a guide for anyone who would like to become a transport pilot and he has not met flying yet. Further the thesis includes a balance sheet of the training strategy in financial terms and their own possibilities of the adept, that anyone who considers the traffic flying should think of well before starting. The thesis also includeds the return on investment, which may be crucial in any decision-making. In addition, it addresses the issue of loans and the pilot takes a look at new trends in aviation
238

Mitigation of airspace congestion impact on airline networks

Vaaben, Bo, Larsen, Jesper 09 November 2020 (has links)
In recent years European airspace has become increasingly congested and airlines can now observe that en-route capacity constraints are the fastest growing source of flight delays. In 2010 this source of delay accounted for 19% of all flight delays in Europe and has been increasing with an average yearly rate of 17% from 2005 to 2010. This paper suggests and evaluates an approach to how disruption management can be combined with flight planning in order to create more proactive handling of the kind of disruptions, which are caused by congested airspace. The approach is evaluated using data from a medium size European carrier and estimates a lower bound saving of several million USD.
239

Passengers' protection and rights in international civil aviation

Balasubramaniam, Usha. January 2007 (has links)
No description available.
240

Resource-Constrained Airline Ground Operations: Optimizing Schedule Recovery under Uncertainty

Evler, Jan 04 November 2022 (has links)
Die zentrale europäische Verkehrsflusssteuerung (englisch: ATFM) und Luftverkehrsgesellschaften (englisch: Airlines) verwenden unterschiedliche Paradigmen für die Priorisierung von Flügen. Während ATFM jeden Flug als individuelle Einheit betrachtet, um die Kapazitätsauslastung aller Sektoren zu steuern, bewerten Airlines jeden Flug als Teilabschnitt eines Flugzeugumlaufes, eines Crew-Einsatzplanes bzw. einer Passagierroute. Infolgedessen sind ATFM-Zeitfenster für Flüge in Kapazitätsengpässen oft schlecht auf die Ressourcenabhängigkeiten innerhalb eines Airline-Netzwerks abgestimmt, sodass die Luftfahrzeug-Bodenabfertigung – als Verbindungselement bzw. Bruchstelle zwischen einzelnen Flügen im Netzwerk – als Hauptverursacher primärer und reaktionärer Verspätungen in Europa gilt. Diese Dissertation schließt die Lücke zwischen beiden Paradigmen, indem sie ein integriertes Optimierungsmodell für die Flugplanwiederherstellung entwickelt. Das Modell ermöglicht Airlines die Priorisierung zwischen Flügen, die von einem ATFM-Kapazitätsengpass betroffen sind, und berücksichtigt dabei die begrenzte Verfügbarkeit von Abfertigungsressourcen am Flughafen. Weiterhin werden verschiedene Methoden untersucht, um die errechneten Flugprioritäten vertraulich innerhalb von kooperativen Lösungsverfahren mit externen Stakeholdern austauschen zu können. Das integrierte Optimierungsmodell ist eine Erweiterung des Resource-Constrained Project Scheduling Problems und integriert das Bodenprozessmanagement von Luftfahrzeugen mit bestehenden Ansätzen für die Steuerung von Flugzeugumläufen, Crew-Einsatzplänen und Passagierrouten. Das Modell soll der Verkehrsleitzentrale einer Airline als taktische Entscheidungsunterstützung dienen und arbeitet dabei mit einer Vorlaufzeit von mehr als zwei Stunden bis zur nächsten planmäßigen Verkehrsspitze. Systemimmanente Unsicherheiten über Prozessabweichungen und mögliche zukünftige Störungen werden in der Optimierung in Form von stochastischen Prozesszeiten und mittels des neu-entwickelten Konzeptes stochastischer Verspätungskostenfunktionen berücksichtigt. Diese Funktionen schätzen die Kosten der Verspätungsausbreitung im Airline-Netzwerk flugspezifisch auf der Basis historischer Betriebsdaten ab, sodass knappe Abfertigungsressourcen am Drehkreuz der Airline den kritischsten Flugzeugumläufen zugeordnet werden können. Das Modell wird innerhalb einer Fallstudie angewendet, um die taktischen Kosten einer Airline in Folge von verschiedenen Flugplanstörungen zu minimieren. Die Analyseergebnisse zeigen, dass die optimale Lösung sehr sensitiv in Bezug auf die Art, den Umfang und die Intensität einer Störung reagiert und es folglich keine allgemeingültige optimale Flugplanwiederherstellung für verschiedene Störungen gibt. Umso dringender wird der Einsatz eines flexiblen und effizienten Optimierungsverfahrens empfohlen, welches die komplexen Ressourcenabhängigkeiten innerhalb eines Airline-Netzwerks berücksichtigt und kontextspezifische Lösungen generiert. Um die Effizienz eines solchen Optimierungsverfahrens zu bestimmen, sollte das damit gewonnene Steuerungspotenzial im Vergleich zu aktuell genutzten Verfahren über einen längeren Zeitraum untersucht werden. Aus den in dieser Dissertation analysierten Störungsszenarien kann geschlussfolgert werden, dass die flexible Standplatzvergabe, Passagier-Direkttransporte, beschleunigte Abfertigungsverfahren und die gezielte Verspätung von Abflügen sehr gute Steuerungsoptionen sind und während 95 Prozent der Saison Anwendung finden könnten, um geringe bis mittlere Verspätungen von Einzelflügen effizient aufzulösen. Bei Störungen, die zu hohen Verspätungen im gesamten Airline-Netzwerk führen, ist eine vollständige Integration aller in Betracht gezogenen Steuerungsoptionen erforderlich, um eine erhebliche Reduzierung der taktischen Kosten zu erreichen. Dabei ist insbesondere die Möglichkeit, Ankunfts- und Abflugzeitfenster zu tauschen, von hoher Bedeutung für eine Airline, um die ihr zugewiesenen ATFM-Verspätungen auf die Flugzeugumläufe zu verteilen, welche die geringsten Einschränkungen im weiteren Tagesverlauf aufweisen. Die Berücksichtigung von Unsicherheiten im nachgelagerten Airline-Netzwerk zeigt, dass eine Optimierung auf Basis deterministischer Verspätungskosten die taktischen Kosten für eine Airline überschätzen kann. Die optimale Flugplanwiederherstellung auf Basis stochastischer Verspätungskosten unterscheidet sich deutlich von der deterministischen Lösung und führt zu weniger Passagierumbuchungen am Drehkreuz. Darüber hinaus ist das vorgeschlagene Modell in der Lage, Flugprioritäten und Airline-interne Kostenwerte für ein zugewiesenes ATFM-Zeitfenster zu bestimmen. Die errechneten Flugprioritäten können dabei vertraulich in Form von optimalen Verspätungszeitfenstern pro Flug an das ATFM übermittelt werden, während die Definition von internen Kostenwerten für ATFM-Zeitfenster die Entwicklung von künftigen Handelsmechanismen zwischen Airlines unterstützen kann.:1 Introduction 2 Status Quo on Airline Operations Management 3 Schedule Recovery Optimization Approach with Constrained Resources 4 Implementation and Application 5 Case Study Analysis 6 Conclusions / Air Traffic Flow Management (ATFM) and airlines use different paradigms for the prioritisation of flights. While ATFM regards each flight as individual entity when it controls sector capacity utilization, airlines evaluate each flight as part of an aircraft rotation, crew pairing and passenger itinerary. As a result, ATFM slot regulations during capacity constraints are poorly coordinated with the resource interdependencies within an airline network, such that the aircraft turnaround -- as the connecting element or breaking point between individual flights in an airline schedule -- is the major contributor to primary and reactionary delays in Europe. This dissertation bridges the gap between both paradigms by developing an integrated schedule recovery model that enables airlines to define their optimal flight priorities for schedule disturbances arising from ATFM capacity constraints. These priorities consider constrained airport resources and different methods are studied how to communicate them confidentially to external stakeholders for the usage in collaborative solutions, such as the assignment of reserve resources or ATFM slot swapping. The integrated schedule recovery model is an extension of the Resource-Constrained Project Scheduling Problem and integrates aircraft turnaround operations with existing approaches for aircraft, crew and passenger recovery. The model is supposed to provide tactical decision support for airline operations controllers at look-ahead times of more than two hours prior to a scheduled hub bank. System-inherent uncertainties about process deviations and potential future disruptions are incorporated into the optimization via stochastic turnaround process times and the novel concept of stochastic delay cost functions. These functions estimate the costs of delay propagation and derive flight-specific downstream recovery capacities from historical operations data, such that scarce resources at the hub airport can be allocated to the most critical turnarounds. The model is applied to the case study of a network carrier that aims at minimizing its tactical costs from several disturbance scenarios. The case study analysis reveals that optimal recovery solutions are very sensitive to the type, scope and intensity of a disturbance, such that there is neither a general optimal solution for different types of disturbance nor for disturbances of the same kind. Thus, airlines require a flexible and efficient optimization method, which considers the complex interdependencies among their constrained resources and generates context-specific solutions. To determine the efficiency of such an optimization method, its achieved network resilience should be studied in comparison to current procedures over longer periods of operation. For the sample of analysed scenarios in this dissertation, it can be concluded that stand reallocation, ramp direct services, quick-turnaround procedures and flight retiming are very efficient recovery options when only a few flights obtain low and medium delays, i.e., 95% of the season. For disturbances which induce high delay into the entire airline network, a full integration of all considered recovery options is required to achieve a substantial reduction of tactical costs. Thereby, especially arrival and departure slot swapping are valuable options for the airline to redistribute its assigned ATFM delays onto those aircraft that have the least critical constraints in their downstream rotations. The consideration of uncertainties in the downstream airline network reveals that an optimization based on deterministic delay costs may overestimate the tactical costs for the airline. Optimal recovery solutions based on stochastic delay costs differ significantly from the deterministic approach and are observed to result in less passenger rebooking at the hub airport. Furthermore, the proposed schedule recovery model is able to define flight priorities and internal slot values for the airline. Results show that the priorities can be communicated confidentially to ATFM by using the concept of 'Flight Delay Margins', while slot values may support future inter-airline slot trading mechanisms.:1 Introduction 2 Status Quo on Airline Operations Management 3 Schedule Recovery Optimization Approach with Constrained Resources 4 Implementation and Application 5 Case Study Analysis 6 Conclusions

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