Optimisation of Low-Thrust and Hybrid Earth-Moon Transfers

This paper presents an optimization procedure to generate fast and low-∆v Earth-Moon transfer trajectories, by exploiting the multi-body dynamics of the Sun-Earth-Moon system. Ideal (first-guess) trajectories are generated at first, using two coupled planar circular restricted three-body problems, one representing the Earth-Moon system, and one representing the Sun-Earth. The trajectories consist of a first ballistic arc in the Sun-Earth system, and a second ballistic arc in the Earth-Moon system. The two are connected at a patching point at one end (with an instantaneous ∆v), and they are bounded at Earth and Moon respectively at the other end. Families of these trajectories are found by means of an evolutionary optimization method. Subsequently, they are used as first-guess for solving an optimal control problem, in which the full three-dimensional 4-body problem is introduced and the patching point is set free. The objective of the optimisation is to reduce the total ∆v, and the time of flight, together with introducing the constraints on the transfer boundary conditions and of the considered propulsion technology. Sets of different optimal trajectories are presented, which represents trade-off options between ∆v and time of flight. These optimal transfers include conventional solar-electric low-thrust and hybrid chemical/solar-electric high/low-thrust, envisaging future spacecraft that can carry both systems. A final comparison is made between the optimal transfers found and only chemical high-thrust optimal solutions retrieved from literature

A Heuristic Strategy to Compute Ensemble of Trajectories for 3D Low Cost Earth-Moon Transfers

The problem of finding optimal trajectories is essential for modern space mission design. When considering multibody gravitational dynamics and exploiting both low-thrust and high-thrust and alternative forms of propulsion such as solar sailing, sets of good initial guesses are fundamental for the convergence to local or global optimal solutions, using both direct or indirect methods available to solve the optimal control problem. This paper deals with obtaining preliminary trajectories that are designed to be good initial guesses as input to search optimal low-energy short-time Earth-Moon transfers with ballistic capture. A more realistic modelling is introduced, in which the restricted four-body system Sun-Earth-Moon-Spacecraft is decoupled in two patched planar Circular Restricted Three-Body Problems, taking into account the inclination of the orbital plane of the Moon with respect to the ecliptic. We present a heuristic strategy based on the hyperbolic invariant manifolds of the Lyapunov orbits around the Lagrangian points of the Earth- Moon system to obtain ballistic capture orbits around the Moon that fulfill specific mission requirements. Moreover, quasi-periodic orbits of the Sun-Earth system are exploited using a genetic algorithm to find optimal solutions with respect to total Dv, time of flight and altitude at departure. Finally, the procedure is illustrated and the full transfer trajectories assessed in view of relevant properties. The proposed methodology provides sets of low-cost and shorttime initial guesses to serve as inputs to compute fully optimized three-dimensional solutions considering different propulsion technologies, such as low, high, and hybrid thrust, and/or using more realistic models

Fast Earth-Moon transfers with ballistic capture

This contribution deals with fast Earth-Moon transfers with ballistic capture in the patched three-body model. We compute ensembles of preliminary solutions using a model that takes into account the relative inclination of the orbital planes of the primaries. The ballistic capture orbits around the Moon are obtained relying on the hyperbolic invariant structures associated to the collinear Lagrangian points of the Earth-Moon system, and the Sun-Earth system portion of the transfers are quasiperiodic orbits obtained by a genetic algorithm. The trajectories are designed to be good initial guesses to search optimal cost-efficient short-time Earth-Moon transfers with ballistic capture in more realistic models

Larval food quantity affects development time, survival and adult biological traits that influence the vectorial capacity of Anopheles darlingi under laboratory conditions

BACKGROUND: The incidence of malaria in the Amazon is seasonal and mosquito vectorial capacity parameters, including abundance and longevity, depend on quantitative and qualitative aspects of the larval diet. Anopheles darlingi is a major malaria vector in the Amazon, representing >95% of total Anopheles population present in the Porto Velho region. Despite its importance in the transmission of the Plasmodium parasite, knowledge of the larval biology and ecology is limited. Studies regarding aspects of adult population ecology are more common than studies on larval ecology. However, in order develop effective control strategies and laboratory breeding conditions for this species, more data on the factors affecting vector biology is needed. The aim of the present study is to assess the effects of larval food quantity on the vectorial capacity of An. darling under laboratory conditions. METHODS: Anopheles darlingi was maintained at 28°C, 80% humidity and exposed to a daily photoperiod of 12 h. Larvae were divided into three experimental groups that were fed either a low, medium, or high food supply (based on the food amounts consumed by other species of culicids). Each experiment was replicated for six times. A cohort of adults were also exposed to each type of diet and assessed for several biological characteristics (e.g. longevity, bite frequency and survivorship), which were used to estimate the vectorial capacity of each experimental group. RESULTS: The group supplied with higher food amounts observed a reduction in development time while larval survival increased. In addition to enhanced longevity, increasing larval food quantity was positively correlated with increasing frequency of bites, longer blood meal duration and wing length, resulting in greater vectorial capacity. However, females had greater longevity than males despite having smaller wings. CONCLUSIONS: Overall, several larval and adult biological traits were significantly affected by larval food availability. Greater larval food supply led to enhance larval and production and larger mosquitoes with longer longevity and higher biting frequency. Thus, larval food availability can alter important biological traits that influence the vectorial capacity of An. darlingi

Aspectos do projeto “copa de futebol do mundo escolar” em uma escola pública de Florianópolis: relação entre as disciplinas

TCC (Graduação) - Universidade Federal de Santa Catarina - Centro de Desportos - Educação Física - Licenciatura.Esta pesquisa se trata de uma análise e reflexão de um projeto intitulado como “Copa de Futebol do Mundo Escolar” em uma escola pública de Florianópolis. O objetivo desta pesquisa é analisar e refletir sobre a Educação Física como componente curricular na Educação Básica e a relação entre as disciplinas. Trata-se de um estudo de campo, de abordagem qualitativa com delineamento exploratório. Na revisão de literatura trataremos de aspectos da cultura, educação e escola, histórico da Educação Física e esta como componente curricular. Em relação ao projeto veremos características da escola onde aconteceu, como este foi planejado, como foi executado, quais foram os projetos realizados e como os professores o avaliaram. Como resultados do projeto tiveram vinte e seis atividades realizadas em diversas turmas e disciplinas. Este projeto foi uma oportunidade para a interdisciplinaridade, o futebol e da Copa do Mundo foram os conhecimentos integradores e foram abordados por muitos professores em suas aulas, porém, ao analisar a relação entre os professores houve pouca articulação para a realização de um trabalho em conjunto

A concepção da política de assistência social e sua efetivação em municípios goianos : o novo jargão e o conservadorismo renitente

Tese (doutorado)—Universidade de Brasília, Instituto de Ciências Humanas, Departamento de Serviço Social, Pós-graduação em Política Social, 2012.Esta tese analisa a concepção da política de assistência social, constituída em mais de duas décadas, desde a Constituição Federal de 1988 à implantação da nova Política Nacional e Norma Operacional Básica do Sistema Único de Assistência Social, e a correspondência destes referentes com experiências municipais no Estado de Goiás. Foram pesquisados três municípios de grande porte, os mais populosos, de economia mais desenvolvida e com maior Produto Interno Bruto do Estado (Goiânia, Anápolis e Aparecida de Goiânia). Explicitar o que as mudanças ocorridas trouxeram de inovação e o que conservaram do passado, em meio aos reveses e contradições da realidade, na implantação da assistência social como direito constituiu o grande desafio desta pesquisa. Constatou-se que, mesmo no contexto da hegemonia neoliberal, ocorreram avanços no tempo estudando, mas a herança histórica do conservadorismo expõem as contradições da institucionalização do Sistema Único de Assistência Social (Suas). A perspectiva de superação das formas tradicionais de gestão dos serviços, programas, benefícios e projetos da assistência social, trazida pela PNAS e NOB/SUAS, tem sido interditada pelos limites dos conceitos adotados, pelas condições em que se materializa e, ainda, pelo contexto de contrarreformas que confronta e derrui a lógica do direito. Nas realidades municipais estudadas prevalece o tecnicismo, a fragmentação, o assistencialismo, com desprofissionalização e voluntarismo. São traços comuns a tendência à psicologização, à moralização e controle social dos usuários, a ausência de compreensão da assistência social, as condições precárias de trabalho, recursos insuficientes e equipamentos inadequados para o atendimento com qualidade. Pautado, sobretudo, pelas demandas da transferência de renda condicionada, notadamente o Bolsa Família, o SUAS inova na aparência, mas essencialmente segue confirmando as características de um Estado liberal, tanto na concepção quanto na implementação, pois mantém a disjunção entre a política e a economia no enfrentamento focalizado das expressões da questão social. ______________________________________________________________________________ ABSTRACTThis thesis examines the conception of social assistance policy, incorporated in more than two decades, since the Federal Constitution of 1988, the deployment of the new National Policy and Basic Operating Standard Single system of Social assistance, and matching those on municipal experiences in the State of Goiás. Were searched three large cities, the most populous, most developed economy and gross domestic product of the State, they are Goiânia, Anápolis and Aparecida de Goiânia. Explain what the changes have brought innovation and what they got from the past, in the midst of the setbacks and the contradictions of reality, in the implementation of social assistance as a right constitutes the major challenge of this research. It was noted that, even in the context of neoliberal hegemony, there have been advances in time studying, but the historical legacy of conservatism expose the contradictions of the institutionalization of the Social Assistance System (SUAS). The prospect of overcoming traditional forms of management of services, programs, benefits and social assistance projects, brought by PNAS and NOB/ITS has been closed by the limits of the concepts adopted, the conditions under which materializes and, even, by the context of confronting unchangeable reforms and stop working the logic of the law. In the studied municipal realities prevails the technicality, fragmentation, the paternalism, with lack of professionalism and being voluntarism. Are common traits the tendency toward psychology, moralizing and social control of the users, the lack of understanding of social assistance, the poor conditions of work, insufficient resources and inadequate equipment for the service quality. Guided, above all, by the demands of the conditional cash transfer, notably Family welfare (Bolsa Familia), ITS innovates in appearance, but essentially follows confirming the features of a liberal State, both in design and implementation, polices your innovates in appearance, but essentially follows confirming the features of a liberal State, both in design and implementation, since it keeps the disjunction between politics and Economics in the confrontation focused social issue expressions. ______________________________________________________________________________ RÉSUMÉCette thèse se penche sur la conception de la politique d'aide sociale, incorporé dans plus de deux décennies, depuis la Constitution fédérale de 1988, le déploiement du nouveau système d'aide sociale, la politique nationale et base de fonctionnement Standard unique et correspondent à celles des expériences municipales dans l'état de Goiás. Ont été recherchés trois grandes villes, la plus peuplées, plus développé économie et brut produit intérieur de l'État (Goiânia, Anápolis et Aparecida de Goiânia). Expliquer ce que les changements ont apporté de l'innovation et ce qu'ils le passé, au milieu les contretemps et les contradictions de la réalité, dans la mise en oeuvre de l'aide sociale comme un droit constitue le défi majeur de cette recherche. Il a été noté que, même dans le contexte de l'hégémonie néolibérale, il y a eu des progrès dans l'étude du temps, mais l'héritage historique du conservatisme expose les contradictions de l'institutionnalisation du Social Assistance système (SUAS). La perspective de surmonter les formes traditionnelles de gestion des services, des programmes, des avantages et des projets d'assistance sociale, opposant PNAS et NOB / ITS a été fermé par les limites des concepts adoptés, les conditions dans lesquelles se concrétise et, même, par le contexte de contrarreformes et derrises la logique de la Loi. Dans les réalités municipales ont étudié l'emporte la technicité, la fragmentation, le paternalisme, avec desprofissionalization et le bénévolat. Traits communs sont la tendance psychologism, moralisateur et sociale le contrôle des utilisateurs, le manque de compréhension de l'aide sociale, les mauvaises conditions de travail, manque de ressources et l'équipement inadéquat pour la qualité du service. Guidés, avant tout, par les exigences du transfert conditionnel en espèces, notamment la Bolsa Familia, ITS innove en apparence, mais suit essentiellement confirmant les caractéristiques d'un État libéral, tant dans la conception et la mise en oeuvre, parce que ceux d'un État libéral, tant dans la conception et la mise en oeuvre, car elle conserve la disjonction entre la politique et l'économie dans la confrontation a porté les expressions question sociale

Era uma vez... a literatura infantil que circula na escola : uma análise de edições adaptadas de contos de fadas

Esta dissertação possui como temática a literatura infantil que circula na escola, especialmente, analisando edições populares adaptadas de contos de fadas. Dentre as coleções encontradas nos acervos investigados em duas escolas municipais – educação infantil e ensino fundamental - de um município da região metropolitana de Porto Alegre/RS, destacou-se a presença de determinadas séries com publicações de textos adaptados muito sucintos e com pouco cuidado editorial, preferencialmente, de “contos de fadas”, ao lado dos acervos oficiais distribuídos às escolas pelo Ministério de Educação (PNBE, PNLD, PNAIC). A partir desta constatação, meu objetivo, nesta dissertação, foi o de analisar criticamente adaptações de textos considerados “clássicos da literatura infantil”, encontrados nas escolas, realizando um cotejo com os "originais" [ou versões mais conhecidas], identificando as modificações e verificando, de maneira geral, os critérios que presidiram suas modificações. Considerando que estas coleções integram o circuito pedagógico nas instituições, realizei uma análise das adaptações de dez clássicos: “O Patinho Feio”, “João e o Pé de Feijão”, “Branca de Neve”, “A Bela e a Fera”, “A Bela Adormecida”, “Cinderela”, “Chapeuzinho Vermelho”, “João e Maria”, “Os Três Porquinhos” e “O Pequeno Polegar”, tomando como referência alguns estudos sobre contos de fadas e sobre adaptação (CADEMARTORI, CECCANTINI, HUTCHEON, CARVALHO, SHAVIT, entre outros). A análise das edições adaptadas, considerando tanto o projeto gráfico dos livros quanto as permanências e modificações dos textos, em relação às obras mais tradicionais, nos permitiu evidenciar o limitado potencial literário destas obras, uma vez que não privilegiam a riqueza das narrativas originais, tampouco sustentam a recepção destas histórias pelo leitor. Tornou-se evidente que a publicação de adaptações constitui uma estratégia do mercado editorial para o largo consumo de livros que possam “ensinar algo” para as crianças. Neste sentido, a investigação é produtiva, à medida que coloca em xeque o conceito de “literatura infantil” ou “livros para crianças” no circuito escolar.This paper focuses on children’s literature in the school, particularly analysing popular issues of fairytales. Among works found in collections investigated in two municipal children’s and primary schools in the city of Porto Alegre (RS), the presence of particular series published from very brief and poorly edited texts, especially, about ‘fairytales’, as well as official collections the Ministry of Education (PNBE, PNLD, PNAIC) distributed to schools. Thus my aim was to analyse critically adaptations of texts considered as ‘children’s literature classics’ found in schools, by comparing them with ‘originals’ (or more popular versions), identifying changes and generally verifying criteria for such changes. Considering that these collections follow pedagogical paths in institutions, I make an analysis of adaptations from ten classics: The Ugly Duckling, Jack and the Beanstalk, Snow White, Beauty and the Beast, Sleeping Beauty, Cinderella, Little Red Riding Hood, Hansel and Gretel, The Three Little Pigs, and Tom Thumb. Here we have drawn to some studies about fairytales and adaptations such as Cademartori, Ceccantini, Hutcheon, Carvalho, Shavit, among others. Analysing these adapted works, by considering both books’ graphic part and attachment or change of traditional, allow us to show that these works have limited literary potential, once they do not favour the richness of the original narratives nor sustain the readers’ reception of these stories, which shows that publication of adaptations constitutes a strategy of the publishing market for the large consumption of books that may ‘teach something’ for children. In this perspective, the investigation is useful as it challenges the concept of ‘children’s literature’ or ‘children’s books’

Pensamento Liminar e Emancipação na Personagem Tita, em Como Água para Chocolate

Este trabalho verifica a construção do pensamento liminar e a emancipação do subalterno por meio da análise das atitudes da personagem Tita, de Como água para chocolate (1993). A protagonista, ao enfrentar uma tradição familiar em que a filha mais nova não pode se casar por ter de cuidar da mãe durante toda a vida, começa a desestabilizar a subjugação que rege a família, mantido por sua mãe, chamada, na diegese, de Mamãe Elena. Para cumprir tal proposta, serão utilizados, neste artigo, prioritariamente, o conceito de Walter Mignolo (2003) para “pensamento liminar” e o de “subalternidade” proposta por John Beverley (2004)