This thesis addresses the challenges in the efficient and robust generation and optimization of three-dimensional landing trajectories for fixed-wing aircraft subject to prescribed boundary conditions and constraints on maneuverability and collision avoidance. In particular, this thesis focuses on the airliner emergency landing scenario and the minimization of landing time. The main contribution of the thesis is two-fold. First, it provides a hierarchical scheme for integrating the complementary strength of a variety of methods in path planning and trajectory optimization for the improvement in efficiency and robustness of the overall landing trajectory optimization algorithm. The second contribution is the development of new techniques and results in mesh refinement for numerical optimal control, optimal path tracking, and smooth path generation, which are all integrated in a hierarchical scheme and applied to the landing trajectory optimization problem. A density function based grid generation method is developed for the mesh refinement process during numerical optimal control. A numerical algorithm is developed based on this technique for solving general optimal control problems, and is used for optimizing aircraft landing trajectories. A path smoothing technique is proposed for recovering feasibility of the path and improving the tracking performance by modifying the path geometry. The optimal aircraft path tracking problem is studied and analytical results are presented for both the minimum-time, and minimum-energy tracking with fixed time of arrival. The path smoothing and optimal path tracking methods work together with the geometric path planner to provide a set of feasible initial guess to the numerical optimal control algorithm. The trajectory optimization algorithm in this thesis was tested by simulation experiments using flight data from two previous airliner accidents under emergency landing scenarios.The real-time application of the landing trajectory optimization algorithm as part of the aircraft on-board automation avionics system has the potential to provide effective guidelines to the pilots for improving the fuel consumption during normal landing process, and help enhancing flight safety under emergency landing scenarios. The proposed algorithms can also help design optimal take-off and landing trajectories and procedures for airports.

Il presente programma di ricerca approfondisce l’uso dell’Expressive Writing (EW) con gli adolescenti a partire da tre studi, organizzati in modo sequenziale. Lo Studio 1 indaga l’efficacia e i fattori di moderazione dell’EW con gli adolescenti tramite meta-analisi. In particolare, è stata eseguita una review quantitativa degli studi sull’EW con partecipanti in età adolescenziale, attraverso i seguenti passaggi: ricerca sistematica e codifica degli studi; calcolo degli effect size; analisi dei moderatori. Lo Studio 2 confronta sperimentalmente sugli adolescenti gli effetti a breve e lungo termine di due tipi di istruzioni di scrittura, una convenzionale (EW) e l’altra orientata cognitivamente (CEW), elaborata sulla base dei risultati della meta-analisi. Le analisi sono state finalizzate a testare gli effetti della modificazione delle consegne di scrittura sul funzionamento emotivo e sociale degli adolescenti. Lo Studio 3 consiste in un’analisi secondaria dello Studio 2 ed esplora l’esito dell’intervento in funzione delle traiettorie di cambiamento dei meccanismi cognitivi (“Self-distancing”) rilevati negli scritti, tramite Group-Based Trajectory Modeling. I risultati degli studi sono discussi in funzione delle loro implicazioni teoriche e pratiche. / The present research program aims at evaluating the use of Expressive Writing (EW) with adolescents through three studies, organized in a progressive fashion. Study 1 investigates the efficacy and moderators of EW with adolescents through a meta-analysis. The study performed a quantitative review of the EW interventions with adolescent samples, according to the following steps: systematic literature search and coding of the studies; calculation of the effect size; analysis of the moderators. Study 2 experimentally compares the short- and long-term effects of the traditional writing condition (EW) to a cognitively-oriented EW condition (CEW) on a sample of adolescents. The analyses had the objective to test the effects of altering the writing instructions on social and emotional adjustment of participants. Study 3 consists in a secondary analysis of the written essays collected in Study 2 with the intent of examining the effects of the intervention as a function of the cognitive processes (“Self-distancing”) observed during the writing sessions by means of the Group-Based Trajectory Modeling. The findings are discussed on the basis of their theoretical and practical implications.

LEAL, Bruno de Carvalho. Da modelagem Conceitual à Representação Lógica de Trajetórias em SGBDOR e Sistemas de DW. 2011. 120 f. : Dissertação (mestrado) - Universidade Federal do Ceará, Centro de Ciências, Departamento de Computação, Fortaleza-CE, 2011. / Submitted by guaracy araujo (guaraa3355@gmail.com) on 2016-06-03T18:06:29Z No. of bitstreams: 1 2011_dis_bcleal.pdf: 2151043 bytes, checksum: 6cb423b35ccbf999cc937ddda41507be (MD5) / Approved for entry into archive by guaracy araujo (guaraa3355@gmail.com) on 2016-06-03T18:07:43Z (GMT) No. of bitstreams: 1 2011_dis_bcleal.pdf: 2151043 bytes, checksum: 6cb423b35ccbf999cc937ddda41507be (MD5) / Made available in DSpace on 2016-06-03T18:07:43Z (GMT). No. of bitstreams: 1 2011_dis_bcleal.pdf: 2151043 bytes, checksum: 6cb423b35ccbf999cc937ddda41507be (MD5) Previous issue date: 2011 / Com o aumento do número de dispositivos móveis equipados com serviços de localização geográfica, tem se tornado cada vez mais economicamente e tecnicamente possível capturar os percursos (i.e. trajetórias) dos objetos móveis. Muitas aplicações interessantes têm sido desenvolvida com intuito de explorar análises de trajetórias de objetos móveis. Por exemplo, em sistemas de gerenciamento de veículos de entrega, pode ser realizado tanto o monitoramento dos veículos quanto análises para apoio a decisões estratégicas. De modo geral, as trajetórias podem ser analisadas em duas perspectivas: tempo real e histórica. Além disso, aplicações de trajetórias compartilham uma necessidade em comum que é o registro mais estruturado do movimento. Isso permite manipular trajetórias como objetos de primeira classe e adicionar qualquer semântica requerida pela aplicação e, também, a criação de métodos robustos e eficientes para agregar conjuntos de trajetórias de forma a permitir a realização de análises complexas. Este trabalho estende um trabalho anterior na modelagem conceitual de trajetórias pela generalização da ideia de paradas e movimentos e pela definição de um conjunto de funções de agregação para trajetórias. Neste trabalho é proposto, ainda, duas abordagens por modelagem, ambas baseadas em meta-esquemas, para elaboração de esquemas de trajetórias para ambiente transacional e multidimensional. Para demonstrar e provar nossas contribuições apresentamos um caso de estudo real sobre trajetórias de caminhões de entrega. Os resultados experimentais demonstram que as abordagens de modelagem oferecem a flexibilidade necessária para lidar com a complexidade da semântica das trajetórias em análises de tempo real e histórica.

Entre 2004 e 2014, a Educação Superior brasileira passou pelo maior processo de expansão já empreendido em sua curta história. Embora a maior parte das matrículas tenha se mantido na rede privada, foi no setor público que ocorreu a ampliação mais significativa do número de instituições, cursos, matrículas e funções docentes, especialmente na rede federal. Tal processo possibilitou o ingresso não somente de maior número de discentes oriundos de famílias pobres e sem tradição de longevidade escolar, mas também de docentes que trilharam trajetórias formativas e profissionais marcadas por condicionantes sociais próprios desse tipo de origem, os quais relacionam as escolas que puderam frequentar com as escolhas possíveis quanto à formação acadêmica e a inserção no mundo do trabalho. Com referencial teóricometodológico bourdieusiano e o objetivo de desvelar os condicionantes sociais de trajetórias de docentes de origem popular que ingressaram numa universidade federal durante a expansão, foram coletados dados em fontes documentais diversas e também por meio de questionário, observação de locais de trabalho e entrevista semiestruturada, de natureza autobiográfica. Do total de 1.427 docentes que compunham o quadro efetivo da Universidade Federal de São Paulo (Unifesp) em julho de 2014, o questionário foi respondido por 339 agentes de diversas origens sociais e, entre eles, foram entrevistados 31 docentes de origem popular, distribuídos em cinco campi e diversas áreas de conhecimento. Para situar sóciohistoricamente o espaço de confluência das trajetórias, a análise parte de um histórico da instituição, desde sua criação, por e para uma parcela da elite paulistana, como Escola Paulista de Medicina (EPM), até as transformações que a tornaram uma universidade multicampi, por força da expansão que visava democratizar seu público. Em seguida, dois capítulos se dedicam a expor os aspectos considerados mais relevantes nas trajetórias. A análise revela 9 condicionantes sociais mais proeminentes: i- influência do nível de escolaridade familiar nas formas de adesão ao jogo da escolarização; ii- acesso a diferentes oportunidades de formação escolar; iii- relação entre as restrições materiais sofridas durante a formação básica e a precariedade das estratégias de acúmulo de capital cultural; iv- implicação da formação inicial na escolha da formação universitária; v- necessidade de recursos materiais para assegurar a vida universitária; vi- convivência acadêmica como impulsora da formação e carreira; vii- obtenção de bolsa de estágio em nível de Pós-Doutorado; viii- expansão das universidades federais; ix- configurações específicas das áreas de conhecimento como balizador dos modos de trabalho. Conclui-se que os condicionantes sociais diretamente relacionados à origem de classe não justificam integralmente os percursos, as escolhas e os investimentos na carreira; porém, delineiam o horizonte de possibilidades e operam sobre a estruturação dos esquemas de percepção, avaliação, pensamento e ação de cada agente, cumprindo função decisiva na definição do destino e do desenvolvimento profissional. Portanto, tais condicionantes não podem ser ignorados quando se discute a expansão ou democratização do acesso à Educação Superior, sobretudo no que diz respeito à importância da assistência estudantil como política de permanência para que os estudantes pobres conquistem a longevidade escolar. / Between 2004 and 2014, Higher Education in Brazil experienced the largest expansion in its short history. Although most registrations took place in private institutions, the public sector faced the most significant enlargement in the number of institutions, courses, registrations and teaching functions, especially in the federal system. Such process enabled not only access to the university by a greater number of students from poor families and with no tradition of schooling longevity, but also professors who have had formative and professional trajectories marked by social constraints, typical of such origin, which relate to the schools they were able to attend with their possible choices regarding academic education and transition to the labor market. Supported by Bourdieu´s theoretical/methodological framework and with the purpose of unveiling the social constraints of the trajectories of professors from grass-roots background who were admitted to a federal university at the time of the expansion, data collection came from several documental sources and also from a questionnaire, the observation of the workplaces and an autobiographical semi-structured interview. Out of 1,427 professors who were the effective faculty of the Federal University of São Paulo (Unifesp) in July, 2014, the questionnaire got responses from 339 agents from several social origins and, out of them, 31 professors from grass-roots background were interviewed, spread in five campuses and from different areas of knowledge. In order to locate socio-historically the space of confluence of the trajectories, the analysis starts with a history of institution, since it was established, by and for a portion of São Paulo´s elite, as the São Paulo Medical School (EPM), up to the changes that turned it into a multi-campus university, as a result of the expansion aimed at democratizing its public. Next, two chapters are dedicated to exposing the most remarkable aspects in the trajectories. The analysis reveals nine (9) outstanding social constraints: i- influence of the family schooling level in the forms of adherence to the schooling game; ii- access to different opportunities of education; iii- relation between the material limitations occurring during basic education and the precarious strategies of building up cultural capital; iv- implication of the basic education in the choice of higher education to be pursued; v- need of material resources to achieve a university degree; vi- academic conviviality as an impeller to education and career; vii- getting a scholarship as a PostDoctoral intern; viii- expansion of the federal universities; ix- specific configurations of the areas of knowledge as a guide of the ways of work. Conclusion was that the social constraints directly associated with the class origin do not thoroughly justify the routes taken, the choices and investments made in the career; however, they outline the horizon of possibilities and play a role onto the structuring of the schemes of perception, evaluation, thinking and action of each agent, fulfilling a decisive function in defining the professional destiny and development. Therefore, such constraints cannot be ignored when one discusses the expansion or democratization of the access to Higher Education, mainly concerning the importance of student assistance as a policy to retain poor students and make them achieve schooling longevity.

Neste trabalho apresentamos uma versão do Teorema de Poincaré-Bendixson para campos vetoriais contínuos na garrafa de Klein. Como conseqüência, mostramos que a garrafa de Klein não possui campo vetorial contínuo com trajetória injetiva recorrente / We present a version of the Poincaré-Bendixson Theorem on the Klein bottle for continuous vector fields. As a consequence, we obtain the fact that the Klein bottle does not admit continuous vector fields having a recurrent injective trajectory

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Motion planning problems are characterized by huge search spaces and complex obstacle structures with no concise mathematical expression. The fixed-wing airplane application considered in this thesis adds differential constraints and point-wise bounds, i. e. an infinite number of equality and inequality constraints. An optimal trajectory planning approach is presented, based on the randomized Rapidly-exploring Random Trees framework (RRT*). The local planner relies on differential flatness of the equations of motion to obtain tree branch candidates that automatically satisfy the differential constraints. Flat output trajectories, in this case equivalent to the airplane's flight path, are designed using Bézier curves. Segment feasibility in terms of point-wise inequality constraints is tested by an indicator integral, which is evaluated alongside the segment cost functional. Although the RRT* guarantees optimality in the limit of infinite planning time, it is argued by intuition and experimentation that convergence is not approached at a practically useful rate. Therefore, the randomized planner is augmented by a deterministic variational optimization technique. To this end, the optimal planning task is formulated as a semi-infinite optimization problem, using the intermediate result of the RRT(*) as an initial guess. The proposed optimization algorithm follows the feasible flavor of the primal-dual interior point paradigm. Discretization of functional (infinite) constraints is deferred to the linear subproblems, where it is realized implicitly by numeric quadrature. An inherent numerical ill-conditioning of the method is circumvented by a reduction-like approach, which tracks active constraint locations by introducing new problem variables. Obstacle avoidance is achieved by extending the line search procedure and dynamically adding obstacle-awareness constraints to the problem formulation. Experimental evaluation confirms that the hybrid approach is practically feasible and does indeed outperform RRT*'s built-in optimization mechanism, but the computational burden is still significant. / Bewegungsplanungsaufgaben sind typischerweise gekennzeichnet durch umfangreiche Suchräume, deren vollständige Exploration nicht praktikabel ist, sowie durch unstrukturierte Hindernisse, für die nur selten eine geschlossene mathematische Beschreibung existiert. Bei der in dieser Arbeit betrachteten Anwendung auf Flächenflugzeuge kommen differentielle Randbedingungen und beschränkte Systemgrößen erschwerend hinzu. Der vorgestellte Ansatz zur optimalen Trajektorienplanung basiert auf dem Rapidly-exploring Random Trees-Algorithmus (RRT*), welcher die Suchraumkomplexität durch Randomisierung beherrschbar macht. Der spezifische Beitrag ist eine Realisierung des lokalen Planers zur Generierung der Äste des Suchbaums. Dieser erfordert ein flaches Bewegungsmodell, sodass differentielle Randbedingungen automatisch erfüllt sind. Die Trajektorien des flachen Ausgangs, welche im betrachteten Beispiel der Flugbahn entsprechen, werden mittels Bézier-Kurven entworfen. Die Einhaltung der Ungleichungsnebenbedingungen wird durch ein Indikator-Integral überprüft, welches sich mit wenig Zusatzaufwand parallel zum Kostenfunktional berechnen lässt. Zwar konvergiert der RRT*-Algorithmus (im probabilistischen Sinne) zu einer optimalen Lösung, jedoch ist die Konvergenzrate aus praktischer Sicht unbrauchbar langsam. Es ist daher naheliegend, den Planer durch ein gradientenbasiertes lokales Optimierungsverfahren mit besseren Konvergenzeigenschaften zu unterstützen. Hierzu wird die aktuelle Zwischenlösung des Planers als Initialschätzung für ein kompatibles semi-infinites Optimierungsproblem verwendet. Der vorgeschlagene Optimierungsalgorithmus erweitert das verbreitete innere-Punkte-Konzept (primal dual interior point method) auf semi-infinite Probleme. Eine explizite Diskretisierung der funktionalen Ungleichungsnebenbedingungen ist nicht erforderlich, denn diese erfolgt implizit durch eine numerische Integralauswertung im Rahmen der linearen Teilprobleme. Da die Methode an Stellen aktiver Nebenbedingungen nicht wohldefiniert ist, kommt zusätzlich eine Variante des Reduktions-Ansatzes zum Einsatz, bei welcher der Vektor der Optimierungsvariablen um die (endliche) Menge der aktiven Indizes erweitert wird. Weiterhin wurde eine Kollisionsvermeidung integriert, die in den Teilschritt der Liniensuche eingreift und die Problemformulierung dynamisch um Randbedingungen zur lokalen Berücksichtigung von Hindernissen erweitert. Experimentelle Untersuchungen bestätigen, dass die Ergebnisse des hybriden Ansatzes aus RRT(*) und numerischem Optimierungsverfahren der klassischen RRT*-basierten Trajektorienoptimierung überlegen sind. Der erforderliche Rechenaufwand ist zwar beträchtlich, aber unter realistischen Bedingungen praktisch beherrschbar.

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<p dir="ltr">Since the 2000s, there has been a growing interest in qualitative research in the field of Japanese language education, including life story research (e.g., Miyo, 2015). One of the purposes of life story research in Japanese language education is to pay attention to, listen to, and describe the voices of people to whom Japanese language education has so far paid little attention (Miyo, 2014, 2015a). Many studies have listened to the voices of Japanese language learners living in Japan and described their experiences (e.g., Miyo, 2009; Sato, 2015; Maruyama & Ozawa, 2018). However, many studies have not paid particular attention to the region where the learners are staying. One gets the impression that the place could be anywhere as long as the learners are in Japan. Further, cross-cultural adaptation research often focuses on international cross-cultural contact. However, in recent years, it has been pointed out that cross-cultural contact also involves regional differences within a single country (Gui et al., 2012; Berry, 2016). In other words, foreigners staying in a host country experience not only intercultural contact between their own country and the host country but also intercultural contact arising from regional differences within the host country, making the adaptation process complex.</p><p dir="ltr">This narrative case study focused on one American learner of Japanese, Kevin (pseudonym), and his experience on Futaba Island (pseudonym) and analyzed his process of cross-cultural adaptation. Data was collected from his diary and semi-structured interviews with him over six months. The collected data were then graphically represented using the method of Trajectory Equifinality Modeling (TEM) (Sato et al., 2009; Sato et al., 2014). The data obtained in this study showed that Kevin’s back-and-forth between Futaba Island and the mainland impeded and facilitated his cross-cultural adaptation in different ways. Unlike people in large cities on the mainland, people on Futaba Island stare at Kevin and treat him as a special guest, which made him aware of cultural barriers, leading him to construct an identity as an outsider and feel, “I will never fully integrate into Japanese society.” Furthermore, when he traveled to the mainland, he experienced reverse culture shock by encountering many American tourists that he cannot see on Futaba Island. Seeing American tourists behaving incompatibly with Japanese cultural norms made Kevin realize that he was more integrated into Japanese society than he had thought. All of this suggests that when considering the cross-cultural adaptation of foreigners staying in Japan, it is essential to take a place-based perspective on where they are in Japan and where they have been during their stay. Furthermore, just because a person is staying in the host country does not mean that cross-cultural adaptation is influenced by factors that are exclusive to the host country. While staying in the host country, one’s cross-cultural adaptation may be influenced by people from or by events in their home country. It is necessary to take into account home country-related factors as well.</p>