Space Mechanics And Control
Mostrando 1-8 de 8 artigos, teses e dissertações.
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1. Utilização dos métodos SDRE e filtro de Kalman para o controle de atitude de simuladores de satélites / Application of SDRE and Kalman filter methods to attitude control of satellite simulators.
Space missions involving automatic procedures for big attitude maneuvers and control using new non-linear control techniques require from the satellite Attitude Control System (ACS) reliability, adequate performance and robustness. In that context, experimental validation of new equipment and/or non-linear control techniques through prototypes is the way to
Publicado em: 2009
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2. Método para a avaliação do ganho empregado pelo piloto em ensaios de PIO / Method to evaluate pilot gain in PIO flight test
A method is proposed to verify losed-loop adequate flight test piloting gain in PIO aircraft certification. The synthetic tracking task PIO flight test is used. The theory is based on the entropy concept from information theory and on the structural pilot model of the human pilot. The method is presented for single axis pilot tracking maneuvers and offers a
Publicado em: 2009
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3. Representação Matemática do Comportamento Mecânico Cíclico de Solos Saturados e não Saturados / Mathematical Representation of the Cyclic Mechanical Behaviour of Saturated and Unsaturated Soils
Granular materials, such as soils, exhibit a relatively complex mechanical behaviour. Usually, the mechanical behaviour of soils is studied with the aid of the Continuum Mechanics. Materials under cyclic loadings exhibit a dierent mechanical behaviour, with respect to monotonic loadings. The mathematical theory of elastoplasticity has been employed to the nu
Publicado em: 2006
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4. Estudo dos erros sistemáticos inerentes a um sensor de estrelas de cabeça fixa, quando à localização relativa de estrelas / Study of systematic errors inherent to fixed-head star trackers with respect to the relative position of stars
Sensores de estrelas são sensores de atitude usados em veículos espaciais capazes de fornecer sua atitude com precisão da ordem de segundos de arco. A atitude é determinada quando as coordenadas das estrelas, medidas pelo sensor em seu sistema de coordenadas, são comparadas com as direções conhecidas de estrelas obtidas em um catálogo de estrelas. Po
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 29/03/2005
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5. Estudo comparativo de técnicas de controle de atitude em três eixos para satélites artificiais / Comparative study of three axes attitude control techniques for artificial satellites
Neste trabalho propõe-se um estudo sobre técnicas de controle de atitude para satélites estabilizados em três eixos e, através da modelagem e simulação computacional, analisar, comparar e fazer um estudo de alternativas/viabilidade de sistemas de controle de atitude (ACS) em três eixos, com base nos requisitos de missões espaciais. Para o estudo de
Publicado em: 2005
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6. Estudo dos erros sistemáticos inerentes a um sensor de estrelas de cabeça fixa, quando à localização relativa de estrelas / Study of systematic errors inherent to fixed-head star trackers with respect to the relative position of stars
Star trackers are attitude sensors used in spacecrafts capable of providing accurate attitude in arc-seconds range. The attitude information is provided when the star coordinates, measured by the sensor in its frame, are compared with known star directions obtained from a star catalog. Nevertheless, as in all measurement instruments, the measures are likely
Publicado em: 2005
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7. Impact of CpG methylation on structure, dynamics and solvation of cAMP DNA responsive element
Methylation of CpG motifs in DNA is involved in the control of gene expression and in several other epigenic effects. It suppresses also the immuno-stimulation properties of bacterial or viral DNAs that contain CpGs. However, effects of methylation on the DNA structure and dynamics are not clear. Here we carried out a 10 ns MD simulation, confronted to
Oxford University Press.
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8. Resting energy expenditure and oxygen cost of breathing in patients with cystic fibrosis.
BACKGROUND: Resting energy expenditure (REE) is often increased and may contribute towards energy imbalance in patients with cystic fibrosis. Several mechanisms may lead to increased REE including the gene defect, the effect of chronic infection, and abnormal pulmonary mechanics. Increased oxygen cost of breathing (OCB) has been demonstrated in patients with