GN&C Sequencing for Orion Rendezvous, Proximity Operations, and Docking

As part of the Artemis program to return humans to the lunar surface, the National Aeronautics and Space Administration is planning to use the Orion Multi- Purpose Crew Vehicle to transport crew to a small orbital platform called Gate- way in cislunar space. To facilitate this activity, Orion is required to perform Rendezvous, Proximity Operations, and Docking (RPOD) with both the Gate- way and the launch vehicle upper stage. The Orion spacecraft uses sequencing in the form of Phases, Segments, Activities, and Modes (PSAM) to configure Guidance, Navigation, & Control (GN&C) software during each portion of the mission. Significant updates to Orion PSAM definitions are required for RPOD. This paper describes the process of defining these new sequencing elements, implementing them in prototype flight software, and testing them in an integrated simulation environment. First, requirements are specified to determine the nominal and off-nominal sequencing behavior necessary to complete the mission. These requirements also specify which software functions should be fully autonomous and which functions require manual interactions from crew or ground operators. Next, the RPOD concept of operations is defined with detailed events listed in a mission timeline. Third, a state machine diagram is developed to show all PSAM states, including all possible transitions between them. After this, the PSAM states and transitions are entered into a sequencing software emulator and parameter values and modes are defined for GN&C software elements. Finally, the PSAM architecture is tested within an integrated simulation environment by connecting it with prototypes of relevant GN&C flight software elements and with detailed vehicle models. After the sequencing design has been finalized and tested, it is implemented in flight software

Decomposição da palhada de culturas para plantio no período de safrinha em solos de tabuleiros costeiros.

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Quinoa: alternativa para diversificação agrícola alimentar.

Este trabalho é o resultado de esforços envidados pelos pesquisadores, seus colaboradores e parceiros, com a finalidade de diversificar a produção de grãos. Os problemas fitossanitários crescentes, como resultado do monocultivo, precisam de solução. Como os autores mencionam, temos de imitar a natureza em sua diversidade, ainda que, do ponto de vista prático, o desafio seja grande. No Bioma Cerrado e no Brasil, predomina o plantio direto, por uma série de vantagens ao produtor, com conseqüências favoráveis ao meio ambiente. Entretanto, como em todos os desafios, a agricultura precisa de aprimoramento para contornar os reveses de sua prática em sistemas monoculturais. Novos problemas podem resultar das ações ligadas ao plantio direto. O não-revolvimento do solo pode aumentar as pragas de solo e as doenças. O inóculo permanece nos restos de culturas e nas plantas espontâneas que resultam das sementes perdidas na colheita. Cita-se, como exemplo, a ferrugem da soja que depende de plantas vivas para se multiplicar e causar epidemia. Aumentar a diversidade, via rotação, sucessão e cultivos associados não só contribui para diminuir a pressão biótica como também abre novas perspectivas à exploração econômica. A inclusão da quinoa, um pseudocereal exótico, associado à antiga cultura dos Andes, é parte de um trabalho que visa prevenir problemas e tornar a agricultura cada vez mais eficiente, em bases sustentáveis. A atividade agrícola é conservadora, talvez, pelos riscos a ela inerentes. As mudanças encontram barreiras e não tem sido fácil a tarefa de introduzi-las no sistema. Fruto de pesquisa e desenvolvimento recomenda-se a primeira cultivar de quinoa e as técnicas de cultivo; com a divulgação, cresce o interesse dos agricultores e outros segmentos da sociedade humana, especialmente, os ligados à diversificação alimentar. Esta obra reúne informação imprescindível ao cultivo e à utilização da quinoa no Brasil. O espírito pioneiro que têm norteado os trabalhos, certamente trará bons resultados

The Foveal Confluence in Human Visual Cortex

The human visual system devotes a significant proportion of its resources to a very small part of the visual field, the fovea. Foveal vision is crucial for natural behavior and many tasks in daily life such as reading or fine motor control. Despite its significant size, this part of cortex is rarely investigated and the limited data have resulted in competing models of the layout of the foveal confluence in primate species. Specifically, how V2 and V3 converge at the central fovea is the subject of debate in primates and has remained “terra incognita” in humans. Using high-resolution fMRI (1.2 × 1.2 × 1.2 mm3) and carefully designed visual stimuli, we sought to accurately map the human foveal confluence and hence disambiguate the competing theories. We find that V1, V2, and V3 are separable right into the center of the foveal confluence, and V1 ends as a rounded wedge with an affine mapping of the foveal singularity. The adjacent V2 and, in contrast to current concepts from macaque monkey, also V3 maps form continuous bands (∼5 mm wide) around the tip of V1. This mapping results in a highly anisotropic representation of the visual field in these areas. Unexpectedly, for the centermost 0.75°, the cortical representations for both V2 and V3 are larger than that of V1, indicating that more neuronal processing power is dedicated to second-level analysis in this small but important part of the visual field

Elaboração de farinha instantânea de amaranto.

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Composição química comparativa de farinhas instantâneas de quinoa, arroz e milho.

bitstream/item/76343/1/ct52-2002.pd

Diferencas entre o pseudocereal Amaranto e especies de planta daninha, Amaranthaceae.

bitstream/CPAC-2009/24248/1/comtec_69.pd

Chemical and genetic control of fusarium wilt in chickpea and their effects on stand establishment under tropical conditions.

Abstract 87

Aesthetics and Psychological Effects of Fractal Based Design

Highly prevalent in nature, fractal patterns possess self-similar components that repeat at varying size scales. The perceptual experience of human-made environments can be impacted with inclusion of these natural patterns. Previous work has demonstrated consistent trends in preference for and complexity estimates of fractal patterns. However, limited information has been gathered on the impact of other visual judgments. Here we examine the aesthetic and perceptual experience of fractal ‘global-forest’ designs already installed in humanmade spaces and demonstrate how fractal pattern components are associated with positive psychological experiences that can be utilized to promote occupant wellbeing. These designs are composite fractal patterns consisting of individual fractal ‘tree-seeds’ which combine to create a ‘global fractal forest.’ The local ‘tree-seed’ patterns, global configuration of tree-seed locations, and overall resulting ‘global-forest’ patterns have fractal qualities. These designs span multiple mediums yet are all intended to lower occupant stress without detracting from the function and overall design of the space. In this series of studies, we first establish divergent relationships between various visual attributes, with pattern complexity, preference, and engagement ratings increasing with fractal complexity compared to ratings of refreshment and relaxation which stay the same or decrease with complexity. Subsequently, we determine that the local constituent fractal (‘tree-seed’) patterns contribute to the perception of the overall fractal design, and address how to balance aesthetic and psychological effects (such as individual experiences of perceived engagement and relaxation) in fractal design installations. This set of studies demonstrates that fractal preference is driven by a balance between increased arousal (desire for engagement and complexity) and decreased tension (desire for relaxation or refreshment). Installations of these composite mid-high complexity ‘global-forest’ patterns consisting of ‘tree-seed’ components balance these contrasting needs, and can serve as a practical implementation of biophilic patterns in human-made environments to promote occupant wellbeing