Ce travail porte sur la modélisation de la décharge négative dans les grands intervalles d'air soumis à des ondes de tension de type bi-exponentielles (foudre ou manœuvre) ou constantes. Ainsi, un modèle dynamique et autonome permettant de prédire l'ensemble des paramètres macroscopiques de la décharge négative et tenant compte des différentes phases de propagation (initiation de la première couronne, système pilote, formation des leaders d'électrode et spatiaux, jonctions et ré-illuminations, saut final) jusqu'à l'arc en retour, est présenté. Ce modèle est basé sur des schémas électriques équivalents dont les paramètres varient avec le temps en fonction des caractéristiques du canal et de la géométrie de la décharge, les lois de l'électromagnétisme et la théorie des gaz. Les propagations des leaders et des streamers sont basées sur des critères de champs électriques tenant compte de l'aspect aléatoire du trajet de la décharge.<br />Le modèle permet de déterminer les caractéristiques spatio-temporelles de la décharge telles que le courant du leader (canal principal), la charge correspondante, des trajectoires plausibles, sa vitesse instantanée, le gradient de potentiel et le rayon thermique du leader négatif d'électrode, la puissance et l'énergie injectées dans l'intervalle, l'instant et la tension d'amorçage ainsi que l'évolution de l'arc en retour. Il permet également, pour une configuration d'électrodes donnée, de déterminer la tension de claquage U50, constituant ainsi un outil appréciable pour le dimensionnement des structures isolantes. Les résultats issus de ce modèle sont en bon accord avec ceux obtenus expérimentalement.<br />Un modèle de foudre négatif a été également établi en se basant sur la grande similarité observée entre les grandes étincelles de laboratoire et les décharges atmosphériques. Les caractéristiques obtenues à partir de ce modèle ont été trouvées conformes aux mesures effectuées lors des décharges naturelles. L'environnement électromagnétique associé au précurseur de foudre a été ensuite caractérisé et les champs électriques et magnétiques obtenues sont aussi en bon accord avec celles relevées expérimentalement.

The Traffic alert and Collision Avoidance System (TCAS) is an aircraft collision avoidance system designed to prevent mid-air collisions. During an advisory, danger is imminent, and TCAS is assumed to have better, more up-to-date information than the ground operated air traffic control (ATC) facility. Following a TCAS RA is generally the safe course of action during an advisory. However, pilot compliance with RAs is surprisingly low. Results from a TCAS monitoring study show pilots are not complying with many TCAS advisories. As revealed by pilot-submitted Aviation Safety Reporting System (ASRS) reports, this noncompliance could be attributed, in part, to pilot confusion to TCAS operation as well as misunderstandings of the appropriate response to a TCAS issued advisory. This thesis details the development and evaluation of a TCAS training program intended to improve pilots' understanding of TCAS use for collision avoidance in a range of traffic situations. The training program integrated Demonstration Based and Event Based Training techniques. Its efficacy was analyzed in an integrated ATC-cockpit simulator study in which eighteen commercial airline pilots were asked to complete the TCAS training program and afterwards experienced twelve experimental traffic events. The trained pilots' performance was compared to the performance of 16 baseline pilots who did not receive the modified training. Overall, the training program did have a significant impact on the pilots' behavior and response to TCAS advisories. The measure Time Pilots First Achieved Compliance decreased with the trained pilots, as did the measure Autopilot Disconnect Time After RA Initiation. Trained pilots exhibited less aggressive performance in response to a TCAS RA (including a decrease in the measures Altitude Deviation Over Duration Of RA, Average Vertical Rate Difference, Maximum Vertical Rate Difference, and Maximum Vertical Rate). The measure Percent Compliance did not significantly vary between trained and baseline pilots, although trained pilots had a more consistent response in the traffic event with conflicting ATC guidance. Finally, on the post-experiment questionnaires, pilots commented on their increase in understanding of TCAS as well as an increase in their trust in the advisory system. Results of this research inform TCAS training objectives provided by the FAA as well as the design of TCAS training. Additionally, conclusions extend more broadly to improved training techniques for other similar complex, time-critical situations.

Cette thèse porte sur les processus de sélection, formation et encadrement (SFE) des gestionnaires, appelés pilotes et considérés comme agents de changement dans les télécentres communautaires au Mali. Ces processus sont étudiés sous l'angle de leur contribution positive ou négative à l'implantation et au développement de ces centres. Les projets "technologies de l’information et de la communication", initiés par les partenaires techniques et financiers, répondent au besoin des autorités maliennes préoccupées par un souci de connecter les 703 communes du pays. À la suite du sommet mondial sur la société de l’information en décembre 2003 à Genève, l’UNESCO et la Coopération suisse ont décidé d’installer des centres multimédias communautaires dans trois pays d’Afrique (Mali, Mozambique, Sénégal). Ces implantations de télécentres ont été réalisées sur le modèle de ce qui avait été fait en Asie sans tenir compte des besoins réels des bénéficiaires et des conditions particulières (économiques, politiques, culturelles) des sites d’implantation. Malgré les conditions parfois difficiles de l’Afrique, les populations témoignent un enthousiasme réel pour les technologies de communication. Les TIC ont connu une croissance considérable et se sont multipliées partout en Afrique, à des degrés divers. Néanmoins, elles n’ont pas encore atteint la majorité des populations africaines, car 70% de celles-ci vivent en zones rurales souvent marginalisées par les difficultés économiques. Après l’implantation des télécentres, les sites ont donc été confrontés à la difficile tâche de sélectionner les pilotes comme agents de changement. Les responsables chargés de la mise en œuvre des projets ont choisi les pilotes dans leur réseau familial. En ce sens, la thèse met l’accent sur l’importance du rôle d’un pilote dans un télécentre et l’appui qu’il peut générer dans la population bénéficiaire. Nous proposons un modèle qui part de l’action des agents de changement, et ce, afin de potentiellement susciter une prise de conscience chez les décideurs locaux. Nous avons fait une étude de cas sur quatre sites pour mieux connaître les processus de sélection, formation et encadrement des pilotes et nous avons tenté d'identifier les facteurs qui, dans ces processus, ont pu influencer le niveau de réussite de chacun de ces centres. / This dissertation examines the processes of selecting, training, and mentoring managers, also known as "pilots," and considered as change agents in the development of community telecentres in Mali. These processes are analyzed according to their positive and negative outcomes regarding the establishment and development of telecentres. The Information and Communication Technologies (ICT) project, launched by technical and financial partners, responds to the needs of Malian authorities in their efforts to connect the country’s 703 communes. Following the World Summit on the Information Society, held in Geneva on December 2003, UNESCO and the Swiss Agency for Development and Cooperation (SDC) decided to establish multimedia community telecentres in three African countries (Mali, Mozambique, and Senegal). The setting-up of these telecentres was modeled after a similar project conducted previously in Asia, without however taking into account the primary needs of the beneficiaries, nor their specific conditions (both economic, political, and cultural). Despite the difficult conditions that sometimes characterize the African context, African populations express a genuine interest for Information and Communication Technologies. The ICT sector has witnessed a considerable and widespread growth throughout many African countries, although with various degrees of success. However, a majority of the African population has still not been connected, since 70% of the population lives in more economically marginalized rural areas. Once the telecentres were established in various locations, most of them were confronted with the difficult challenge of selecting "pilots," to serve as change agents. Those in charge of selecting the pilots favored people located within their own family networks. Therefore, the dissertation emphasizes the pilot’s decisive role in the telecentres, and the support that he is able to generate within the beneficiary population. We put forward a model starting from the actions of the change agents, hoping to stimulate awareness amongst local deciders. We conducted a case study on four different sites in order to better understand the processes of selecting, training, and mentoring pilots, with a focus on the key factors influencing, for each of those processes, the level of success in all the telecentres.

This study examines the differences between the skills and competencies of New Zealand flight school graduates and the types of skills and competencies believed to define a proficient air transport pilot. In New Zealand the training of professional pilots is directed towards meeting the requirements laid down by the New Zealand Civil Aviation Authority for the licensing of professional pilots. However, some evidence suggests that competence for licensing purposes does not necessarily meet the requirements of the airlines and the types of skills that they require as a prerequisite to airline training. Although not clearly defined, this shortfall has been recognised for several decades and traditional thinking is that extra flying experience gained as a general aviation pilot will develop the skills necessary for entry into airline pilot training. The importance that pilots of differing experience levels attach to technical and non-technical skills and their perception of the training effectiveness of those skills and how deficiencies in those skills contributed to aircraft accidents was explored by a four stage study including: i) a review and analysis of flight test results obtained from graduate pilots on a university air transport pilot programme; ii) the analysis of responses to questionnaires supplied to three pilot groups within the New Zealand aviation industry; iii) the analysis of air transport aircraft accidents and their primary and contributing causes; and iv) interviews with qualified airline pilots working for New Zealand airlines. The results indicated that throughout the spectrum of experience and qualifications, from student pilot to airline pilot, the technical skill of aircraft handling was highly valued and the training in this skill was considered by all pilots to be satisfactory. In contrast, while non-technical skill deficiencies were found to be primary or contributing factors in many aircraft accidents, less importance was attached to non-technical skills by all pilot groups. The training effectiveness of these skills was rated as only moderately effective or of minimal effectiveness. The findings are discussed and recommendations are made for the improvement of basic flight training. In addition, a model is proposed for the fast tracking of flight school graduates into the airline training schools. Several areas for future research are also proposed.

The recent emphasis on Affirmative Action policies in South African corporations has illuminated the issue of cultural diversity in organizations and the difficulties arising from this transition and change. One such difficulty is the problem of intercultural communication where miscommunication can have life-threatening consequences. This problem is particularly critical in the operational environment of the passenger aircraft flight deck where small group factors, as well as intercultural issues must be taken into account. In this thesis the problem of intercultural communication in such contexts as a consequence of Affirmative Action is examined. The data for this thesis comprises the communication of five culturally diverse flight crews. A multi-method was used for the gathering and analysis of this data. This involved the use of video-taped flight simulator sessions, and personal interviews with each crew member. The subjects themselves were involved in identifying key communication problems from the video and interpretation of the data. Three levels of analysis were used in the interpretation of the findings - the individual, the group and the organization. The factors which affected communication at each level in the small, culturally diverse group are highlighted. Furthermore, factors which influence the climate in which communication takes place are also considered. The implications for Affirmative Action are discussed.

A língua franca utilizada na comunicação piloto-controlador ainda é pouco conhecida no meio acadêmico. Poucos estudos têm sido dedicados ao seu contexto de uso e ao mapeamento de suas características lingüísticas principais. Esta pesquisa acadêmica apresenta um estudo mais acurado da atividade de controlador de tráfego aéreo, no que se refere ao uso dessa linguagem de especialidade, além de desenvolver um estudo descritivo da língua franca utilizada na comunicação piloto-controlador para a identificação de suas características lingüísticas principais, com o recorte para a produção de material didático. Por meio da utilização do método do Professor André Camlong, a ferramenta computacional denominada STABLEX, fazemos uma análise descritiva, objetiva e indutiva de um corpus lingüístico, constituído dessa linguagem de especialidade. O que se pretende é oferecer subsídios aos professores de língua estrangeira para a produção do seu próprio material didático para o ensino dessa linguagem. É fato que, em determinados contextos de ensino, a necessidade de aprendizagem dos alunos é tão específica, que os materiais prontos para consumo, disponibilizados nas prateleiras das livrarias ou pelas editoras, não são suficientes, cabendo ao professor a tarefa de elaborá-los. No entanto, essa tarefa não tem se mostrado amistosa, já que o professor não dispõe de \"guias de orientação\", cientificamente justificáveis, para fazê-la. Assim sendo, o processo de elaboração torna-se intuitivo e empírico e, na grande maioria das vezes, restringese à adoção de fórmulas já consagradas de apresentação dos conteúdos. Acreditamos ser fundamental o correto entendimento das reais necessidades lingüísticas de um determinado público-alvo, para que haja mais condições de se estabelecerem processos mais ricos e eficientes de ensino e aprendizagem de qualquer língua estrangeira. / The lingua franca used in the communication between pilots and controllers is still not well known in the academic community. Few studies about its use and mapping of its main linguistic characteristics have been made. This theoretical research introduces an accurate study on the language used in the activity of air traffic controllers and develops a descriptive study of the lingua franca used in the communication between pilots and controllers, in order to identify its main linguistic characteristics towards material production. By using the method developed by Professor André Camlong and the computational tool STABLEX, an objective descriptive and inductive analysis of a linguistic corpus constituted by the language used in the ATC specialty has been conducted. The aim of this work is to provide language teachers with subsides for ATC material production hence helping teachers to elaborate materials that meet the very specific needs of their students based on the real needs of the stakeholders so as they can establish a more fruitful and efficient language teaching and learning process.

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This thesis analyses image of Czechoslovakian pilots in local film production. It focuses on films about pilots from Second World War and pilots from Czechoslovak people's army. The aim of thesis is to define main characteristics of military pilots in selected films and compare their transformation through time. Analytic part will use visual, semiotic, discursive and narrative analysis concept as theoretical framework. Thesis works on the presumption that image transformation was highly influenced by historical and political development of country. It assumes that pilots from Second World War were portrayed positively in late 1960s and after year 1989 and pilots from Czechoslovak people's army were favored in era of normalization, particularly in 1970s and 1980s.

Although most modern, highly-computerized flight decks are known to be robust to small disturbances and failures, humans still play a crucial role in advanced decision making in off-nominal situations, and accidents still occur because of poor human-automation interaction. In addition to the physical state of the environment, operators now have to extend their awareness to the state of the automated flight systems. To guarantee the accuracy of this knowledge, humans need to know the dynamics or approximate versions of the dynamics that rule the automation. The operator's situation awareness can decline because of a deficient mental model of the aircraft and an excessive workload. This work describes the creation of a computational human agent model simulating cognitive constructs such as situation awareness and mental models known to capture the symptoms of poor human-automation interaction and provide insight into more comprehensive metrics supporting the validation of automated systems in aviation.