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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Os desafios da regulação do setor de transporte aéreo de passageiros no Brasil /

Laplane, Gabriela. January 2005 (has links)
Orientador: Alexandre Sartoris Neto / Banca: Maria Sylvia Macchione Saes / Banca: Maria Alice Rosa Ribeiro / Resumo: A presente dissertação analisa a evolução das políticas regulatórias do transporte aéreo de passageiros no Brasil, identificando as mudanças nas motivações e na forma da intervenção do Governo neste setor desde o início da atividade da aviação no país, até os dias atuais. Entre a década de 1920 e final da década de 1980, o setor era fortemente regulado pelo Governo. Na década de 1990, no âmbito da globalização e da liberalilzação dos mercados, a aviação civil passou por um processo gradual de desregulação. Entretanto, em 2003, o Governo formulou novas diretrizes para o setor que assinalam na direção de uma re-regulação. O objetivo do trabalho é examinar os desafios passados e presentes enfrentados na busca de um modelo regulatório adequado para o transporte aéreo de passageiros no Brasil. Através da comparação entre a evolução das teorias e práticas regulatórias no mundo e da trajetória da regulação da aviação civil brasileira, busca-se identificar os fundamentos teóricos e políticos que poderiam justificar a atual proposta do governo brasileiro de re-regular o setor. Para isto, analisa-se a evolução do modelo regulatório do transporte aéreo no Brasil, dos seus objetivos e da relação entre as políticas industrial e de defesa da concorrência. / Abstract: The present dissertation analyses the evolution of the civil aviation regulatory policies in Brazil identifying the changes in government's motivation and forms of intervention in this sector since the beginning of the civil aviation activity in the country until the current days. Between the decades of 1920 and 1980 the sector was strongly regulated by the government. During the decade of 1990 in the context of globalization and market liberalization the civil aviation went trough gradual process of deregulation. However, in 2003 the government formulated new rules for the sector that point to a tendency to re-regulation. The aim of this research is to examine the past and present challenges faced in the search of a regulatory model that meets the needs of the Brazilian civil aviation. The comparison between the evolution theories and worldwide regulatory practices and the trajectory of the regulation of Brazilian civil aviation aims to identify the theoretical and political foundations that could possible justify the Brazilian government proposal of reregulation of the sector. It analyses the evolution of regulatory modal, its goals and the relationship between industrial and competition policies. / Mestre
2

Intensity of competition in a recently deregulated industry : the airline industry of the European Community

O'Reilly, Margaret Dolores January 1995 (has links)
This thesis examines the liberalisation of the European Community's civil aviation industry and attempts to measure how effective this process has been in achieving its goal of increased competition and greater efficiency. Using the experience in the United States following deregulation of domestic air transport services as a template, the study employs Easton's model of political analysis and Porter's model of competitive forces as a framework for empirical research. This research was carried out with a representative sample of EC airlines, of their suppliers and customers, of providers of substitute services and of the industry's regulators. The results of the research were validated by personal interviews with leading stakeholders in the industry. The main Conclusions drawn from the research are that: i. liberalisation of the European Community air transport market has resulted in an influx of new entrants, an increase in the number of routes operated and a wider availability of discounted fares; ii. to the extent that competition has nevertheless been less fierce than anticipated, this is because the aims of liberalisation have been frustrated by a resistance to change on the part of certain Member States and by the European Commission's inability to prevent further grants of State aid to loss-making flag carriers. Inadequate infrastructure has also acted as a brake on competition; iii. customer choice is strongly influenced by frequency of service and by price. Those airlines which have set out to gain market share and which have pursued low price strategies have benefited most from liberalisation; iv. airlines benefit from selling to a large number of buyers and from having a wide choice of suppliers; V. the only threat of substitution to air travel within the European Community is from the High Speed Train and then only over comparatively short distances.
3

Os desafios da regulação do setor de transporte aéreo de passageiros no Brasil

Laplane, Gabriela [UNESP] 10 1900 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:24:17Z (GMT). No. of bitstreams: 0 Previous issue date: 2005-10Bitstream added on 2014-06-13T18:20:32Z : No. of bitstreams: 1 laplane_g_me_arafcl.pdf: 290605 bytes, checksum: b2fc392729486e5311dffb9f608d0647 (MD5) / A presente dissertação analisa a evolução das políticas regulatórias do transporte aéreo de passageiros no Brasil, identificando as mudanças nas motivações e na forma da intervenção do Governo neste setor desde o início da atividade da aviação no país, até os dias atuais. Entre a década de 1920 e final da década de 1980, o setor era fortemente regulado pelo Governo. Na década de 1990, no âmbito da globalização e da liberalilzação dos mercados, a aviação civil passou por um processo gradual de desregulação. Entretanto, em 2003, o Governo formulou novas diretrizes para o setor que assinalam na direção de uma re-regulação. O objetivo do trabalho é examinar os desafios passados e presentes enfrentados na busca de um modelo regulatório adequado para o transporte aéreo de passageiros no Brasil. Através da comparação entre a evolução das teorias e práticas regulatórias no mundo e da trajetória da regulação da aviação civil brasileira, busca-se identificar os fundamentos teóricos e políticos que poderiam justificar a atual proposta do governo brasileiro de re-regular o setor. Para isto, analisa-se a evolução do modelo regulatório do transporte aéreo no Brasil, dos seus objetivos e da relação entre as políticas industrial e de defesa da concorrência. / The present dissertation analyses the evolution of the civil aviation regulatory policies in Brazil identifying the changes in government's motivation and forms of intervention in this sector since the beginning of the civil aviation activity in the country until the current days. Between the decades of 1920 and 1980 the sector was strongly regulated by the government. During the decade of 1990 in the context of globalization and market liberalization the civil aviation went trough gradual process of deregulation. However, in 2003 the government formulated new rules for the sector that point to a tendency to re-regulation. The aim of this research is to examine the past and present challenges faced in the search of a regulatory model that meets the needs of the Brazilian civil aviation. The comparison between the evolution theories and worldwide regulatory practices and the trajectory of the regulation of Brazilian civil aviation aims to identify the theoretical and political foundations that could possible justify the Brazilian government proposal of reregulation of the sector. It analyses the evolution of regulatory modal, its goals and the relationship between industrial and competition policies.
4

The problem of registration and nationality of aircraft of international operating agencies and the I.C.A.O. Council's resolution on the problem /

Goreish, Ishaq Rasheed Sid Ahmed. January 1970 (has links)
No description available.
5

Clipped Wings: Management discourses during organisational change at Australia's Civil Aviation Authority

Mahoney, James Scott, n/a January 2007 (has links)
Structural change in organisations is stressful for staff and the managers who must implement it. Most change programs use employee communication techniques to support change directions set by senior executive decision makers-dominant coalitions. This research used a single case study to explain the context and management discourses of a major re-structure of an Australian Federal Government agency, the former Civil Aviation Authority (CAA), during the early 1990s. A content analysis examined the use of keywords in management discourses that argued the need for change. The keywords represented the two major change discourses: micro-economic reform and aviation safety regulation. A critical discourse analysis investigated the dominant coalition's discourse strategies to justify change. Content and process communication theories, and the role of framing in organisational change, were used to explain how employees may have reacted to change directions. The research found that change directions were framed as an economic imperative that clashed with a traditional organisational culture that emphasised the primacy of aviation safety. It found that mixed messages by the two principal members of the dominant coalition who drove change exacerbated the clash. The results suggest a need for further analysis of management discourses used to inform employees about structural change, especially in organisations that have legislative responsibilities. Further analysis of change messages framed by dominant coalitions could lead to a deeper understanding ofhow they affect employees and the change process.
6

The problem of registration and nationality of aircraft of international operating agencies and the I.C.A.O. Council's resolution on the problem /

Goreish, Ishaq Rasheed Sid Ahmed. January 1970 (has links)
No description available.
7

Impact of GNSS singular events on the integrity of airport navigation systems / Impact des évènements singuliers GNSS sur l'intégrité des systèmes de navigation aéroportuaires

Montloin, Leslie 10 July 2014 (has links)
Les systèmes GNSS sont actuellement utilisés en aviation civile pour estimer la position et la vitesse de l'avion pendant les phases de route jusqu'aux approches de précision. Etendre l'utilisation de GNSS aux opérations de surface en environnement aéroportuaire et sous de faibles conditions de visibilité reste un challenge pour la communauté aviation civile. En effet, durant ces opérations, les mesures GNSS peuvent être affectées par des évènements singuliers tels que les multi-trajet ou les anomalies ionosphériques. Ces évènements peuvent engendrer des erreurs de position jugées inacceptables en termes de précision et d'intégrité pour assurer le guidage de l'avion. Les algorithmes de surveillance d'intégrité GNSS actuellement utilisés ne sont pas conçus pour prendre totalement en compte les effets de tels évènements. Il est essentiel de développer des algorithmes de surveillance conçus pour protéger les utilisateurs des effets de tels évènements afin de pouvoir utiliser GNSS pour le guidage de l'avion en milieu aéroportuaire et sous de faibles conditions de visibilité. Afin de concevoir de tels algorithmes de surveillance d'intégrité, il est nécessaire de développer des modèles d'erreurs de mesures GNSS et des modèles de pannes GNSS. La thèse a été principalement orientée vers la conception de modèles d'erreurs de mesures GNSS dues aux multi-trajets et vers le développement de modèles de pannes GNSS dues aux multi-trajets. Pour ce faire, un modèle d'erreurs multi-trajets GNSS sur les mesures bi-fréquence GPSL1C+GPSL5 et GalileoE1+GalileoE5a a d'abord été proposé. Ensuite, l'impact des multi-trajets sur l'erreur de position a été étudié. Pour cette étude, un algorithme de couplage serré GPS+Galileo/IRS a été considéré. Cet algorithme est basé sur un filtre de Kalman linéarisé. Une analyse théorique et quantitative a été conduite pour étudier l'impact des erreurs de mesures GNSS dues aux multi-trajets sur le biais et sur la matrice de covariance de l'erreur de position horizontale en sortie de l'algorithme de positionnement considéré. Finalement, un modèle de pannes GNSS dues aux multi-trajets a été proposé. Ce modèle décrit la signature des pannes multi-trajets, les facteurs influençant cette signature, le modèle d'occurrence des pannes multi-trajets ainsi que les conditions d'occurrence de telles pannes / GNSSs are currently used in civil aviation to provide aircraft with position and velocity estimates from en-route to precision approach operations. Extending the use of GNSS to the guidance function during airport surface operations and under zero-visibility conditions remains a challenge. Indeed, during these operations, GNSS measurements may be affected by GNSS singular events, such as multipath or ionosphere anomalies. GNSS singular events may lead to unacceptable position errors in terms of accuracy and integrity for the zero-visibility guidance function. Current GNSS integrity monitoring systems are not designed to totally account for the GNSS singular event effects. The development of GNSS integrity monitoring systems designed to properly protect users from the singular event effects is essential to use GNSS for the guidance function under zero-visibility conditions. GNSS measurement error and integrity failure models are key inputs in the design of GNSS integrity monitoring systems. In this thesis, work has been mainly focused on the development of GNSS multipath measurement errors, on the assessment of the multipath impact on the GNSS-based position error, and on the development of GNSS multipath integrity failure models. For this matter, the dual frequency GPSL1C+GPSL5 and GalileoE1+GalileoE5a multipath pseudo- range error model adapted to airport navigation has been firstly proposed. Next, the impact of multipath on the GNSS-based position error has been assessed. To do so, a double constellation GPS+Galileo/IRS tight coupling algorithm based on a linearized Kalman filter has been selected. The theoretical and quantitative analysis of the impact of the GNSS multipath ranging errors on the horizontal position bias and on the covariance matrix of the horizontal position error have been proposed. Finally, a GNSS multipath integrity failure model has been proposed. The model describes the signature of the GNSS single multipath ranging failures, the factors influencing the signature as well as the occurrence model of these failures and their conditions of occurrence.
8

Policy development framework for aviation strategic planning in developing countries

Itani, Nadine M. January 2015 (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.
9

Modes dégradés résultant de l'utilisation multi constellation du GNSS / Degraded Modes Resulting From The Multi Constellation Use Of GNSS

Ouzeau, Christophe 08 April 2010 (has links)
Actuellement, on constate dans le domaine de la navigation, un besoin croissant de localisation par satellites. Apres une course a l'amelioration de la precision (maintenant proche de quelques centimetres grace a des techniques de lever d'ambiguite sur des mesures de phase), la releve du nouveau defi de l'amelioration de l'integrite du GNSS (GPS, Galileo) est a present engagee. L'integrite represente le degre de confiance que l'on peut placer dans l'exactitude des informations fournies par le systeme, ainsi que la capacite a avertir l'utilisateur d'un dysfonctionnement du GNSS dans un delai raisonnable. Le concept d'integrite du GNSS multi-constellation necessite une coordination au niveau de l'architecture des futurs recepteurs combines (GPS-Galileo). Le fonctionnement d'un tel recepteur dans le cas de passage du systeme multi-constellation en mode degrade est un probleme tres important pour l'integrite de navigation. Cette these se focalise sur les problemes lies a la navigation aeronautique multiconstellation et multi-systeme GNSS. En particulier, les conditions de fourniture de solution de navigation integre sont evaluees durant la phase d'approche APV I (avec guidage vertical). En disposant du GPS existant, du systeme Galileo et d'un systeme complementaire geostationnaire (SBAS), dont les satellites emettent sur des frequences aeronautiques en bande ARNS, la question fondamentale est comment tirer tous les benefices d'un tel systeme multi-constellation pour un recepteur embarque a bord d'un avion civil. En particulier, la question du maintien du niveau de performance durant cette phase de vol APV, en termes de precision, continuite, integrite et disponibilite, lorsque l'une des composantes du systeme est degradee ou perdu, doit etre resolue. L'objectif de ce travail de these est donc d'etudier la capacite d'un recepteur combine avionique d'effectuer la tache de reconfiguration de l'algorithme de traitement apres l'apparition de pannes ou d'interferences dans une partie du systeme GNSS multiconstellation et d'emettre un signal d'alarme dans le cas ou les performances de la partie du systeme non contaminee ne sont pas suffisantes pour continuer l'operation en cours en respectant les exigences de l'aviation civile. Egalement, l'objectif de ce travail est d'etudier les methodes associees a l'execution de cette reconfiguration pour garantir l'utilisation de la partie du systeme GNSS multi-constellation non contaminee dans les meilleures conditions. Cette etude a donc un interet pour les constructeurs des futurs recepteurs avioniques multiconstellation. / The International Civil Aviation Organization (ICAO) has defined the concept of Global Navigation Satellite System (GNSS), which corresponds to the set of systems allowing to perform satellite-based navigation while fulfilling ICAO requirements. The US Global Positioning Sysem (GPS) is a satellite-based navigation system which constitutes one of the components of the GNSS. Currently, this system broadcasts a civil signal, called L1 C/A, within an Aeronautical Radio Navigation Services (ARNS) band. The GPS is being modernized and will broadcast two new civil signals: L2C (not in an ARNS band) and L5 in another ARNS band. Galileo is the European counterpart of GPS. It will broadcast three signals in an ARNS band: Galileo E1 OS (Open Service) will be transmitted in the GPS L1 frequency band and Galileo E5a and E5b will be broadcasted in the same 960-1215 MHz ARNS band than that of GPS L5. GPS L5 and Galileo E1, E5a, E5b components are expected to provide operational benefits for civil aviation use. However, civil aviation requirements are very stringent and up to now, the bare systems alone cannot be used as a means of navigation. For instance, the GPS standalone does not implement sufficient integrity monitoring. Therefore, in order to ensure the levels of performance required by civil aviation in terms of accuracy, integrity, continuity of service and availability, ICAO standards define different systems/algorithms to augment the basic constellations. GPS, Galileo and the augmentation systems could be combined to comply with the ICAO requirements and complete the lack of GPS or Galileo standalone performance. In order to take benefits of new GNSS signals, and to provide the service level required by the ICAO, the architecture of future combined GNSS receivers must be standardized. The European Organization for Civil Aviation Equipment (EUROCAE) Working Group 62, which is in charge of Galileo standardization for civil aviation in Europe, proposes new combined receivers architectures, in coordination with the Radio Technical Commission for Aeronautics (RTCA). The main objective of this thesis is to contribute to the efforts made by the WG 62 by providing inputs necessary to build future receivers architecture to take benefits of GPS, Galileo and augmentation systems. In this report, we propose some key elements of the combined receivers' architecture to comply with approach phases of flight requirements. In case of perturbation preventing one of the needed GNSS components to meet a phase of flight required performance, it is necessary to be able to switch to another available component in order to try to maintain if possible the level of performance in terms of continuity, integrity, availability and accuracy. That is why future combined receivers must be capable of detecting the impact of perturbations that may lead to the loss of one GNSS component, in order to be able to initiate a switch. These perturbations are mainly atmospheric disturbances, interferences and multipath. In this thesis we focus on the particular cases of interferences and ionosphere perturbations. The interferences are among the most feared events in civil aviation use of GNSS. Detection, estimation and removal of the effect of interference on GNSS signals remain open issues and may affect pseudorange measurements accuracy, as well as integrity, continuity and availability of these measurements. In literature, many different interference detection algorithms have been proposed, at the receiver antenna level, at the front-end level. Detection within tracking loops is not widely studied to our knowledge. That is why, in this thesis, we address the problem of interference detection at the correlators outputs. The particular case of CW interferences detection on the GPS L1 C/A and Galileo E1 OS signals processing is proposed. Nominal dual frequency measurements provide a good estimation of ionospheric delay. In addition, the combination of GPS or GALILEO navigation signals processing at the receiver level is expected to provide important improvements for civil aviation. It could, potentially with augmentations, provide better accuracy and availability of ionospheric correction measurements. Indeed, GPS users will be able to combine GPS L1 and L5 frequencies, and future GALILEO E1 and E5 signals will bring their contribution. However, if affected by a Radio Frequency Interference, a receiver can lose one or more frequencies leading to the use of only one frequency to estimate the ionospheric code delay. Therefore, it is felt by the authors as an important task to investigate techniques aimed at sustaining multi-frequency performance when a multi constellation receiver installed in an aircraft is suddenly affected by radiofrequency interference, during critical phases of flight. This problem is identified for instance in [NATS, 2003]. Consequently, in this thesis, we investigate techniques to maintain dual frequency performances when a frequency is lost (L1 C/A or E1 OS for instance) after an interference occurrence.
10

Análise dos modelos para cálculo de níveis de segurança relacionados à operação de veículos aéreos não tripulados. / Analysis of models for calculation of levels of security related to operation of unmanned aerial vehicles.

Oliveira, Cristiane Paschoali de 16 June 2009 (has links)
Desde o início do século XX que há registros do uso de Veículos Aéreos Não Tripulados (VANTs) utilizados com finalidade militar. Mas esta não é a única forma que se pode utilizá-los, o ambiente civil também é próspero em possíveis utilizações deste tipo de aeronave. Faltam ainda estudos e comprovações de que a integração dos VANTs no espaço aéreo juntamente com a aviação tripulada convencional não vá trazer alterações nos níveis de segurança já estabelecidos. Juntam-se a este desafio alguns outros, tais como padronizações de normas, classificações e legislação que regulamente o vôo das aeronaves não tripuladas. A presente dissertação faz uma coletânea de alguns modelos relacionados a cálculos de níveis de segurança no vôo de VANTs, bem como compara esses modelos entre si visando o estabelecimento de um método de escolha do modelo mais adequado para aplicação em alguns cenários civis de utilização. Esse trabalho ainda faz a aplicação desse método considerando os modelos relacionados à segurança dos VANTs. / There are records of the use of Unmanned Aerial Vehicles (UAVs) used for military activities since the beginning of the 20th century. But that is not the only way to use it; the civil environment is also promising as to the use of this kind of aircraft. More studies and validations have to be performed about the alterations in the safety levels with the integration of UAVs in the air space with classic manned air vehicles. There are others challenges such as the standardization of norms, classification and legislation to regulate the Unmanned Aerial Vehicle flights. This dissertation presents some models related to the calculation of the safety levels in UAVs flight, it compares them to establish a method for choosing the most suitable model to apply in some civil scenarios. This work also brings the application of this method considering the models related to the safety of UAVs.

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