[pt] Esta tese apresenta um estudo dos efeitos ionosféricos em um Sistema de Aumento Baseado no Solo (GBAS) em regiões equatorial e de baixas latitudes. A ionosfera afeta a propagação dos sinais de GPS e pode reduzir a precisão do posicionamento nas regiões equatorial e de baixas latitudes. Sistemas auxiliares foram desenvolvidos para atender aos requisitos de segurança da aviação. Nesse contexto, o GBAS fornece maior precisão para correções diferenciais. Para avaliar o desempenho de um GBAS, um modelo de simulação do sinal-no-espaço GPS L1 foi desenvolvido, considerando o retardo ionosférico baseado nas distribuições estatísticas dos resíduos de Conteúdo Eletrônico Total vertical obtido do modelo IRI e estimativas da Rede Brasileira de Monitoramento Contínuo, em combinação com representação para a cintilação ionosférica de amplitude, simulada com base em distribuições de probabilidade (Alfa) - (Mi), bem como a cintilação de fase, gerada de acordo com as relações empíricas entre os índices (s)4 and (Sigma)(Fi). O modelo de sinal do GPS L1 também considera erros de relógios e aleatórios, retardos troposféricos, ambigüidade de ciclo e efeitos de multipercurso, para uma descrição completa. Os resultados de sinal-no-espaço são injetados em um modelo de simulação da instalação terrestre do GBAS, implementado para detectar uma variedade de possíveis anomalias ou falhas no sinal-no-espaço e para gerar correções diferenciais baseadas em algoritmos de monitoramento. O GBAS gera correções e seu desempenho é avaliado para aproximações de aeronaves em diferentes condições ionosféricas nos aeroportos do Rio de Janeiro e Fortaleza, enfatizando a Categoria de aproximação I. Os erros horizontais e verticais são estimados usando correções de GBAS para avaliar a precisão. A integridade do GBAS também é analisada calculando os níveis de proteção horizontal e vertical. / [en] This research presents a study on ionospheric effects on a Ground Based Augmentation System (GBAS) in equatorial and low latitude regions. The ionosphere affects the propagation of GPS signals and can reduce the positioning accuracy in the equatorial and low-latitude regions. Auxiliary systems have been developed to meet the safety requirements of aviation. In this context, GBAS provide higher accuracy for differential corrections. To evaluate the performance of a GBAS, a simulation model of the GPS L1 signal-in-space has been developed, considering ionospheric delay based on statistical distributions of vertical Total Electron Content residuals obtained from IRI model and Rede Brasileira de Monitoramento Contínuo estimates, in combination with amplitude ionospheric scintillation simulated based on (Alfa) - (Mi) probability distributions, as well as phase scintillation, generated according to empirical relationships between the indices (S)4 and (Sigma)(Fi). The GPS L1 signal model also considers clock and random errors, tropospheric delays, ambiguity, and multipath, for a complete description. The signal in space results are injected into a GBAS ground facility simulation model, implemented to detect a varied array of possible anomalies or failures in the signal in space and to generate differential corrections based on monitoring algorithms. The GBAS generates corrections and its performance is evaluated for aircraft approaches under different ionospheric conditions at the Rio de Janeiro and Fortaleza Airports, emphasizing Approach Category I. The horizontal and vertical errors are estimated using GBAS corrections to evaluate the accuracy. The GBAS integrity is also analyzed by computing the horizontal and vertical protection levels.

Thesis (Ph. D.)--Aerospace Engineering, Georgia Institute of Technology, 2008. / Committee Chair: Johnson, Eric; Committee Co-Chair: Calise, Anthony; Committee Member: Prasad, J.V.R.; Committee Member: Tannenbaum, Allen; Committee Member: Tsiotras, Panagiotis.

This diploma thesis is dedicated to the European Commission's project known under the name Single European Sky which pursues an objective to reorganize the current European airspace structure for the more efficient provision of air navigation services purposes. As an introduction, the author sets himself the goal to acquaint the reader with relevant international organizations in the field of civil aviation, introduce him in a general way into the provision of air navigation services' issues, including the situations when these services are being provided across the national boundaries. Following this general reading, the thesis fluently moves on to its main subject matter which is the Single European Sky initiative. An attention is focused on the state of European airspace before the initiative has been launched as well as the preparatory works which resulted in the adoption of the first SES legislative package. The following chapter presents the basic legal framework regulating the Single European Sky as amended by the adoption of the second legislative package. Principal part of the thesis is comprised in the next chapter dealing with the process of project's implementation. Within its framework, the reader's attention is turned, inter alia, to such crucial issues as the national supervisory...

The objective of this thesis is to design a relative navigation and guidance system for unmanned aerial vehicles (UAVs) for vision-based control applications. The vision-based navigation, guidance and control has been one of the most focused on research topics for the automation of UAVs. This is because in nature, birds and insects use vision as the exclusive sensor for object detection and navigation. In particular, this thesis studies the monocular vision-based navigation and guidance. Since 2-D vision-based measurements are nonlinear with respect to the 3-D relative states, an extended Kalman filter (EKF) is applied in the navigation system design. The EKF-based navigation system is integrated with a real-time image processing algorithm and is tested in simulations and flight tests. The first closed-loop vision-based formation flight has been achieved. In addition, vision-based 3-D terrain recovery was performed in simulations. A vision-based obstacle avoidance problem is specially addressed in this thesis. A navigation and guidance system is designed for a UAV to achieve a mission of waypoint tracking while avoiding unforeseen stationary obstacles by using vision information. A 3-D collision criterion is established by using a collision-cone approach. A minimum-effort guidance (MEG) law is applied for a guidance design, and it is shown that the control effort can be reduced by using the MEG-based guidance instead of a conventional guidance law. The system is evaluated in a 6 DoF flight simulation and also in a flight test. For monocular vision-based control problems, vision-based estimation performance highly depends on the relative motion of the vehicle with respect to the target. Therefore, this thesis aims to derive an optimal guidance law to achieve a given mission under the condition of using the EKF-based relative navigation. Stochastic optimization is formulated to minimize the expected cost including the guidance error and the control effort. A suboptimal guidance law is derived based on an idea of the one-step-ahead (OSA) optimization. Simulation results show that the suggested guidance law significantly improves the guidance performance. Furthermore, the OSA optimization is generalized as the n-step-ahead optimization for an arbitrary number of n, and their optimality and computational cost are investigated.

The Civil Air Navigation Services Organisation, the International Federation of Air Traffic Control Associations, the International Air Transport Association and the Civil Air Navigation Services Organisation agree that professionals in the Air Navigation Services Provider Sector require successful organisational leadership to facilitate and manage transformation within the highly regulated Air Navigation Services Provider Sector. Detailed organisational leadership requirements and associated leadership training and development needs are, however, not specified by the Civil Air Navigation Services Organisation. An opportunity therefore existed to investigate leadership traits and behaviours within a specific context. This research project is contextualised within a safety-conscious, highly regulated and technology-driven industry (the South African Aviation Industry), a safety-critical sector (Air Navigation Services) and specifically the Air Traffic and Navigation Services Company. It was found that little academic research has been done to address the role of followers in the leadership process and to determine what followers expect and require from their leaders. The research problem statement, in response to this research necessity, is: “How can follower experiences and expectations of leadership behaviours in a safety-critical commercial environment be collected, analysed, understood, structured and utilised to aid leadership development?” An ethnographic research case study approach allowed the researcher to investigate the multifarious phenomena that constitute the current views (experiences and expectations) held by followers with regard to leadership behaviour qualities. A mixed methods approach was followed. Data collection was facilitated by means of individual interviews, focus group interviews, field notes and a structured questionnaire. Qualitative data were inductively analysed to identify the recurring patterns and common themes and quantitative data were deductively analysed to assess the nature of existing conditions and relevance. Data and method triangulation was implemented to determine whether multiple sources of data agreed, and to obtain better, cross-checked insights. Findings from this research study provided academic, industry, process and methodology insights into views held by followers regarding leadership and followership constructs. Definitions and perspectives held and reported by followers regarding leaders and leadership, characteristics of preferred and undesired leadership styles, relational and emotional bonds between followers and their leaders acknowledged the presence, value and influence of follower mental models. In this case followers contextualised leadership roles and responsibilities and suggested a transformational leadership style as a desired state. Findings also emphasised a need to appreciate the importance of the social exchange and social contingency theories of leadership in order to create a better understanding of leadership by emphasising the importance of context when studying leaders and leadership from a follower perspective. Obtained follower insights resulted in a structured leadership training and development needs analysis process framed within the specific context. Future research efforts in this regard may be aimed at determining the necessity to educate followers to critically appreciate and evaluate leadership performance and creating a better understanding of how followers’ mental models internally represent complex, dynamic systems and how these representations change over time. / Business Management / DBL

<p>The purpose of this essay is to investigate how well vision and strategies communicates from division level to underlying business unit levels with focus on the Balanced Scorecard Concept. The investigation was carried out within the ANS division and two of its underlying business units at the LFV Group (Swedish Airports and Air Navigation Services). ANS is responsible for the air navigation services in Sweden and the production of the services is carried out of the business units AER (En Route) and ATA (Tower and Approach). With Air Navigation Services means supervision and conducting air traffic mainly within national air space. The purpose of the services is to insure that air traffic could be carried out in a safe way.</p><p>The Balanced Scorecard was introduced for the first time in the beginning of the 1990´s. The authors behind the concept were Robert S. Kaplan and David P. Norton. The Balanced Scorecard, as a management tool, considers not only financial targets but take into account non financial targets as well because they have also a great influence on an organizations performance. The purpose of the scorecard concept is to deliver a balanced picture of organizations performance indicators, which gives information of key elements today, tomorrow and in the future. The LFV Group and its division ANS implemented the scorecard concept in the middle 1990´s and today the scorecard is a corn stone in the business process.</p><p>During several years Kaplan and Norton have developed the scorecard concept, especially with a focus to communicate a clear message throughout the organization. The latest compliment to the Balanced Scorecard is the Strategy Map. The Strategy Map is a single document and it has a main objective to explain the strategy. To do that the Strategy Map describe how local defined targets are connected to and contributes to the overall target for the organization.</p><p>To establish a picture of how ANS mediates vision and strategies to the underlying business units AER and ATA and how the message will be understood by the employees the authors of this essay have done several interviews and one opinion poll.</p><p>To communicate vision and strategies ANS establish a business plan for the whole division. ANS business plan is then a guiding star when the business units establish their business plans. The division and the business unit’s business plans are therefore very similar to each other and the structure is based on the Balanced Scorecard concept.</p><p>We have found out in this investigation that the communication of vision and strategies works well between division management and the underlying business units and its management with today’s application of the Balanced Scorecard. On the other hand the communication of vision and strategies with the scorecard concept to all employees is unsatisfactory. Workforce on underlying units below the management level have an unclear picture of the Balanced Scorecards function in the management process with purpose to send a clear message of vision on strategies.</p><p>The application of the scorecard concept is not similar for all units within the ANS. One unit for example has developed a Strategy Map to explain the strategy focus for the employees, other unit’s works more conventional with the basic concept of the scorecard. A more similar leadership could give a more positive effect and send a clear view to all employees. Through competence and contacts within the organization there are opportunities for education and development of the scorecard concept for the ANS division.</p> / <p>Syftet med denna uppsats är att undersöka hur väl vision och strategier förmedlas från divisionsnivå till underliggande affärsområdesnivå med avseende på det balanserade styrkortets utformning.</p><p>Undersökningen genomfördes på division ANS och två av ANS underliggande affärsområden AER och ATA vid svenska Luftfartsverket. ANS ansvarar för flygtrafiktjänsten i Sverige vilket sköts av AER och ATA. Flygtrafiktjänst innebär bland annat att övervaka och dirigera flygplan inom tilldelat luftrummet, detta för att kunna bedriva flygtrafik på ett säkert sätt.</p><p>Det balanserade styrkortet presenterades för första gången i början av 1990-talet av upphovsmännen Robert S. Kaplan och David P. Norton. Det balanserade styrkortet tar inte bara hänsyn till finansiella mått utan även icke finansiella mått vilket ger en mer balanserade syn på verksamheten. Luftfartsverket och division ANS började arbeta relativt tidigt med det balanserade styrkortet. I ett samarbete med ett konsultbolag i mitten av 1990-talet utformades ett balanserat styrkort för LFV som än idag arbetas efter.</p><p>Under årens lopp har Kaplan och Norton utvecklat styrkortet, speciellt med avseende på att kommunicera budskap ut i organisationen med hjälp av styrkortet. Det senaste komplementet till styrkortet är Strategikartan som utgörs av ett enskilt dokument och har som uppgift att förklara en strategi. Detta genom att visa och förklara hur ett enskilt uppsatt mål bidrar till helheten i en organisation.</p><p>För att få en uppfattning om hur ANS förmedlar vision och strategier till de underliggande affärsområdena AER och ATA och hur budskapet uppfattas av medarbetarna har intervjuer och en enkätundersökning genomförts.</p><p>För att förmedla vision och strategier upprättar ANS en affärsplan för hela divisionen. ANS affärsplan ligger sedan till grund för de affärsplaner som upprättas för respektive affärsområde. Divisionens och affärsområdenas affärsplaner är snarlika varandra och är uppbyggda på en struktur enlig konceptet med det balanserade styrkortet.</p><p>Resultatet som har framkommit i undersökningen är att kommunikationen av vision och strategier från divisionsledning till ledning för affärsområde ATA och AER fungerar bra med det balanserades styrkortets nuvarande utformning.</p><p>Däremot så finns det brister i kommunikationen av vision och strategier från affärsområdesledning ut till de underliggande produktionsenheterna. På dessa underliggande organisatoriska enheter så upplevs inte nuvarande styrkortskonceptet fungera i samma utsträckning med avseende på uppgiften att förmedla vision och strategier.</p><p>Tillämpningen av styrkortskonceptet skiljer sig dock mellan produktionsenheterna i affärsområdena. Detta exemplifieras av då ATCC-enheten i Stockholm har utvecklat styrkortkonceptet med en strategikarta och där upplevs kommunikationen ha förbättras. Konceptet med strategikarta skulle mycket väl kunna vara applicerbart på andra enheter och till och med för hela divisionens verksamhet. Genom att nyttja den kompetens och kontakter som idag finns inom verksamheten finns det stora möjligheter för utbildning och utveckling av styrkortskonceptet för division ANS.</p>

The Civil Air Navigation Services Organisation, the International Federation of Air Traffic Control Associations, the International Air Transport Association and the Civil Air Navigation Services Organisation agree that professionals in the Air Navigation Services Provider Sector require successful organisational leadership to facilitate and manage transformation within the highly regulated Air Navigation Services Provider Sector. Detailed organisational leadership requirements and associated leadership training and development needs are, however, not specified by the Civil Air Navigation Services Organisation. An opportunity therefore existed to investigate leadership traits and behaviours within a specific context. This research project is contextualised within a safety-conscious, highly regulated and technology-driven industry (the South African Aviation Industry), a safety-critical sector (Air Navigation Services) and specifically the Air Traffic and Navigation Services Company. It was found that little academic research has been done to address the role of followers in the leadership process and to determine what followers expect and require from their leaders. The research problem statement, in response to this research necessity, is: “How can follower experiences and expectations of leadership behaviours in a safety-critical commercial environment be collected, analysed, understood, structured and utilised to aid leadership development?” An ethnographic research case study approach allowed the researcher to investigate the multifarious phenomena that constitute the current views (experiences and expectations) held by followers with regard to leadership behaviour qualities. A mixed methods approach was followed. Data collection was facilitated by means of individual interviews, focus group interviews, field notes and a structured questionnaire. Qualitative data were inductively analysed to identify the recurring patterns and common themes and quantitative data were deductively analysed to assess the nature of existing conditions and relevance. Data and method triangulation was implemented to determine whether multiple sources of data agreed, and to obtain better, cross-checked insights. Findings from this research study provided academic, industry, process and methodology insights into views held by followers regarding leadership and followership constructs. Definitions and perspectives held and reported by followers regarding leaders and leadership, characteristics of preferred and undesired leadership styles, relational and emotional bonds between followers and their leaders acknowledged the presence, value and influence of follower mental models. In this case followers contextualised leadership roles and responsibilities and suggested a transformational leadership style as a desired state. Findings also emphasised a need to appreciate the importance of the social exchange and social contingency theories of leadership in order to create a better understanding of leadership by emphasising the importance of context when studying leaders and leadership from a follower perspective. Obtained follower insights resulted in a structured leadership training and development needs analysis process framed within the specific context. Future research efforts in this regard may be aimed at determining the necessity to educate followers to critically appreciate and evaluate leadership performance and creating a better understanding of how followers’ mental models internally represent complex, dynamic systems and how these representations change over time. / Business Management / DBL

The purpose of this essay is to investigate how well vision and strategies communicates from division level to underlying business unit levels with focus on the Balanced Scorecard Concept. The investigation was carried out within the ANS division and two of its underlying business units at the LFV Group (Swedish Airports and Air Navigation Services). ANS is responsible for the air navigation services in Sweden and the production of the services is carried out of the business units AER (En Route) and ATA (Tower and Approach). With Air Navigation Services means supervision and conducting air traffic mainly within national air space. The purpose of the services is to insure that air traffic could be carried out in a safe way. The Balanced Scorecard was introduced for the first time in the beginning of the 1990´s. The authors behind the concept were Robert S. Kaplan and David P. Norton. The Balanced Scorecard, as a management tool, considers not only financial targets but take into account non financial targets as well because they have also a great influence on an organizations performance. The purpose of the scorecard concept is to deliver a balanced picture of organizations performance indicators, which gives information of key elements today, tomorrow and in the future. The LFV Group and its division ANS implemented the scorecard concept in the middle 1990´s and today the scorecard is a corn stone in the business process. During several years Kaplan and Norton have developed the scorecard concept, especially with a focus to communicate a clear message throughout the organization. The latest compliment to the Balanced Scorecard is the Strategy Map. The Strategy Map is a single document and it has a main objective to explain the strategy. To do that the Strategy Map describe how local defined targets are connected to and contributes to the overall target for the organization. To establish a picture of how ANS mediates vision and strategies to the underlying business units AER and ATA and how the message will be understood by the employees the authors of this essay have done several interviews and one opinion poll. To communicate vision and strategies ANS establish a business plan for the whole division. ANS business plan is then a guiding star when the business units establish their business plans. The division and the business unit’s business plans are therefore very similar to each other and the structure is based on the Balanced Scorecard concept. We have found out in this investigation that the communication of vision and strategies works well between division management and the underlying business units and its management with today’s application of the Balanced Scorecard. On the other hand the communication of vision and strategies with the scorecard concept to all employees is unsatisfactory. Workforce on underlying units below the management level have an unclear picture of the Balanced Scorecards function in the management process with purpose to send a clear message of vision on strategies. The application of the scorecard concept is not similar for all units within the ANS. One unit for example has developed a Strategy Map to explain the strategy focus for the employees, other unit’s works more conventional with the basic concept of the scorecard. A more similar leadership could give a more positive effect and send a clear view to all employees. Through competence and contacts within the organization there are opportunities for education and development of the scorecard concept for the ANS division. / Syftet med denna uppsats är att undersöka hur väl vision och strategier förmedlas från divisionsnivå till underliggande affärsområdesnivå med avseende på det balanserade styrkortets utformning. Undersökningen genomfördes på division ANS och två av ANS underliggande affärsområden AER och ATA vid svenska Luftfartsverket. ANS ansvarar för flygtrafiktjänsten i Sverige vilket sköts av AER och ATA. Flygtrafiktjänst innebär bland annat att övervaka och dirigera flygplan inom tilldelat luftrummet, detta för att kunna bedriva flygtrafik på ett säkert sätt. Det balanserade styrkortet presenterades för första gången i början av 1990-talet av upphovsmännen Robert S. Kaplan och David P. Norton. Det balanserade styrkortet tar inte bara hänsyn till finansiella mått utan även icke finansiella mått vilket ger en mer balanserade syn på verksamheten. Luftfartsverket och division ANS började arbeta relativt tidigt med det balanserade styrkortet. I ett samarbete med ett konsultbolag i mitten av 1990-talet utformades ett balanserat styrkort för LFV som än idag arbetas efter. Under årens lopp har Kaplan och Norton utvecklat styrkortet, speciellt med avseende på att kommunicera budskap ut i organisationen med hjälp av styrkortet. Det senaste komplementet till styrkortet är Strategikartan som utgörs av ett enskilt dokument och har som uppgift att förklara en strategi. Detta genom att visa och förklara hur ett enskilt uppsatt mål bidrar till helheten i en organisation. För att få en uppfattning om hur ANS förmedlar vision och strategier till de underliggande affärsområdena AER och ATA och hur budskapet uppfattas av medarbetarna har intervjuer och en enkätundersökning genomförts. För att förmedla vision och strategier upprättar ANS en affärsplan för hela divisionen. ANS affärsplan ligger sedan till grund för de affärsplaner som upprättas för respektive affärsområde. Divisionens och affärsområdenas affärsplaner är snarlika varandra och är uppbyggda på en struktur enlig konceptet med det balanserade styrkortet. Resultatet som har framkommit i undersökningen är att kommunikationen av vision och strategier från divisionsledning till ledning för affärsområde ATA och AER fungerar bra med det balanserades styrkortets nuvarande utformning. Däremot så finns det brister i kommunikationen av vision och strategier från affärsområdesledning ut till de underliggande produktionsenheterna. På dessa underliggande organisatoriska enheter så upplevs inte nuvarande styrkortskonceptet fungera i samma utsträckning med avseende på uppgiften att förmedla vision och strategier. Tillämpningen av styrkortskonceptet skiljer sig dock mellan produktionsenheterna i affärsområdena. Detta exemplifieras av då ATCC-enheten i Stockholm har utvecklat styrkortkonceptet med en strategikarta och där upplevs kommunikationen ha förbättras. Konceptet med strategikarta skulle mycket väl kunna vara applicerbart på andra enheter och till och med för hela divisionens verksamhet. Genom att nyttja den kompetens och kontakter som idag finns inom verksamheten finns det stora möjligheter för utbildning och utveckling av styrkortskonceptet för division ANS.

La recherche d'une mesure mondiale et corrective des émissions de gaz à effet de serreafin de réduire l'impact de l'activité aérienne internationale sur les changements climatiques a étéconfrontée à l'émergence d'obstacles, sous forme de conflits de normes, liés au défi général del'interaction entre le droit international de l'aviation civile, le droit international des changementsclimatiques et le droit de l'Union européenne. La conciliation des normes matérielles etinstitutionnelles concernées, sur la base d'une interprétation évolutive de la convention de Chicago,est alors apparue comme l'unique solution pour remédier aux situations conflictuelles constatées.Le recours à cette démarche interprétative maintient néanmoins un climat d'insécurité juridique etpose la question des limites à l'adaptation du droit international de l'aviation civile au défi d'uneprotection du climat mondial. Ce travail d'analyse vise alors à démontrer qu'un recours à cettedémarche interprétative n'est pas toujours nécessaire et qu'une application rigoureuse de ladistinction intrinsèque au droit international de l'aviation civile séparant le domaine de lanavigation aérienne du domaine du transport aérien international est la clef du problème. Ellepermet en effet de proposer une solution corrective respectueuse des ordres juridiques fonctionnelsconcernés tout en rétablissant un climat de sécurité juridique indispensable au développementsoutenable de l'aviation civile internationale. / Looking for a global and corrective measure to reduce greenhouse gas emissions frominternational civil aviation has been facing legal obstacles. These obstacles took the form ofconflicts of norms linked to the general challenge of the interactions between international aviationlaw, climate change law and the law of the European Union. Using evolutionary interpretation ofthe Chicago Convention in order to reconcile norms of substantive and institutional nature emergedas the best solution. However, this method perpetuates legal uncertainty and poses the generalchallenge of flexibly and elasticity of the Chicago Convention in response to the climate changechallenge. This study examines the above mentioned issues of interactions between legal ordersand provides recommendations to restore legal certainty needed to ensure sustainable developmentof international civil aviation. More specifically, this study reveals the underestimated relevance ofthe ongoing distinction between the legal regimes of air navigation and air transport, which is a keylegal element in the search for a global and corrective solution to the impact of international civilaviation on climate change.