Hybrid propulsion technology program: Phase 1, volume 1

A number of booster propulsion system concepts are being considered for the next generation of manned and unmanned space launch vehicles. The one propulsion system concept that has potential for reducing costs with increased safety, reliability, and performance is hybrid propulsion (HP). A HP system may be thought of as a liquid propulsion system with solid fuel or a solid propulsion system with a liquid oxidizer. The liquid propulsion features that are most attractive are the higher specific impulse, clean exhaust, separated propellants, and oxidizer loading just prior to launch. The most attractive solid propulsion features includes low life cycle costs, no rotating machinery, compact size, and a robust case. In addition, a HP system has a robust LO2 tank; provides thrust control for ignition, to alleviate flight loads, and for thrust termination; and uses an inert grain that is not sensitive to anomalies such as cracks, voids, and separations. The object is to develop the technology to enable the application of HP to manned and unmanned space launch vehicles. This program will identify the necessary technology, acquire that technology, and demonstrate that technology. This volume is the executive summary

Hybrid propulsion technology program: Phase 1. Volume 3: Thiokol Corporation Space Operations

Three candidate hybrid propulsion (HP) concepts were identified, optimized, evaluated, and refined through an iterative process that continually forced improvement to the systems with respect to safety, reliability, cost, and performance criteria. A full scale booster meeting Advanced Solid Rocket Motor (ASRM) thrust-time constraints and a booster application for 1/4 ASRM thrust were evaluated. Trade studies and analyses were performed for each of the motor elements related to SRM technology. Based on trade study results, the optimum HP concept for both full and quarter sized systems was defined. The three candidate hybrid concepts evaluated are illustrated

Motion Deblurring in the Wild

The task of image deblurring is a very ill-posed problem as both the image and the blur are unknown. Moreover, when pictures are taken in the wild, this task becomes even more challenging due to the blur varying spatially and the occlusions between the object. Due to the complexity of the general image model we propose a novel convolutional network architecture which directly generates the sharp image.This network is built in three stages, and exploits the benefits of pyramid schemes often used in blind deconvolution. One of the main difficulties in training such a network is to design a suitable dataset. While useful data can be obtained by synthetically blurring a collection of images, more realistic data must be collected in the wild. To obtain such data we use a high frame rate video camera and keep one frame as the sharp image and frame average as the corresponding blurred image. We show that this realistic dataset is key in achieving state-of-the-art performance and dealing with occlusions

Soil management qualification under no-till system in Center Southern Brazil.

No-tillage (NT) system comprises a set of technological processes aimed at exploring farming systems while promoting soil conservation management. Its main principles are: leaving soil undisturbed except for seeding in the drills or rows, the maintenance of permanent soil cover, the diversifi cation of crops by rotation or crop consortium, the adoption of joined harvesting-seeding process to reduce the time gap between operations. Although the NT system was developed to reduce erosion and to promote soil quality, there are several inadequate practices that have been applied in areas where cropping is misnamed as "No-tillage" system, e.g., the use of monoculture, the terraces misuse or elimination, the absence of contour plowing and others that are incompatible with the conservation principles and that lead to losses in soil and water quality and in local biodiversity. In order to improve the soil management in NT areas, a network research program coordinated by Embrapa Soils and supported by Itaipu Binacional has been studying no-tillage in twelve watersheds of six regions in Center-Southern Brazil since 2014. The network is developing indicators to assess soil management and its environmental eff ects at property and watershed scales. The program includes: participatory processes of self-evaluation, adjustment and certification by farmers; monitoring farming systems and small watersheds parameters (soil and plant) in twelve locations; long term experiments in six study-sites; and technology transfer in reference areas for training in NT systems. As preliminary results, the selection of monitoring watersheds has been carried out and the communication process has promoted eff ective participation of farmers in Paranapanema-SP, Londrina-PR, Toledo- PR, Maracaju-MS, Rio Verde-GO and Passo Fundo-RS. In addition, the establishment of local and international institutions network started up actions to improve soil management though no-tillage system.The monitoring approach adopts complementary methods to assess the farming system: IQP which is the No Tillage Participatory Quality Index developed by the Brazilian Federation of No-Till Farms and Irrigation (FEBRAPDP); DRES (Rapid Diagnostic of Soil Structure) to asses management structural quality in areas under NT; and Beta (β) index to classify watershed management based on hydrometeorological data, turbidity time series and sedimentary data set from monitored watersheds

Cortical Thickness of Brain Areas Beyond Stroke Lesions and Sensory-Motor Recovery: A Systematic Review

Background: The clinical outcome of patients suffering from stroke is dependent on multiple factors. The features of the lesion itself play an important role but clinical recovery is remarkably influenced by the plasticity mechanisms triggered by the stroke and occurring at a distance from the lesion. The latter translate into functional and structural changes of which cortical thickness might be easy to quantify one of the main players. However, studies on the changes of cortical thickness in brain areas beyond stroke lesion and their relationship to sensory-motor recovery are sparse. Objectives: To evaluate the effects of cerebral stroke on cortical thickness (CT) beyond the stroke lesion and its association with sensory-motor recovery. Materials and Methods: Five electronic databases (PubMed, Embase, Web of Science, Scopus and the Cochrane Library) were searched. Methodological quality of the included studies was assessed with the Newcastle-Ottawa Scale for non-randomized controlled trials and the Risk of Bias Cochrane tool for randomized controlled trials. Results: The search strategy retrieved 821 records, 12 studies were included and risk of bias assessed. In most of the included studies, cortical thinning was seen at the ipsilesional motor area (M1). Cortical thinning can occur beyond the stroke lesion, typically in regions anatomically connected because of anterograde degeneration. Nonetheless, studies also reported cortical thickening of regions of the unaffected hemisphere, likely related to compensatory plasticity. Some studies revealed a significant correlation between changes in cortical thickness of M1 or somatosensory (S1) cortical areas and motor function recovery. Discussion and Conclusions: Following a stroke, changes in cortical thickness occur both in regions directly connected to the stroke lesion and in contralateral hemisphere areas as well as in the cerebellum. The underlying mechanisms leading to these changes in cortical thickness are still to be fully understood and further research in the field is needed. Systematic Review Registration: https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42020200539; PROSPERO 2020, identifier: CRD42020200539

Organização e gestão da Rede AgroHidro.

O artigo apresenta resultados parciais de um estudo de caráter exploratório realizado para: a) contribuir com os gestores da Rede AgroHidro na identificação de elementos socioinstitucionais favorecedores da sua gestão e organização/estruturação; e b) capturar os tipos de aprendizagens e competências construídas pelos integrantes da Rede a partir das interações comunicacionais realizadas em um espaço de ambiência virtual intitulado Agropedia brasilis.Editores técnicos: Maria Fernanda Moura, Giampaolo Queiroz Pellegrino, Lineu Neiva Rodrigues

Erosive potential of rains in the climate change scenarios in the upper Taquari River Basin, MS, Brazil.

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Constriction size distributions of granular filters: a numerical study

The retention capability of granular filters is controlled by the narrow constrictions connecting the voids within the filter. The theoretical justification for empirical filter rules used in practice includes consideration of an idealised soil fabric in which constrictions form between co-planar combinations of spherical filter particles. This idealised fabric has not been confirmed by experimental or numerical observations of real constrictions. This paper reports the results of direct, particle-scale measurement of the constriction size distribution (CSD) within virtual samples of granular filters created using the discrete-element method (DEM). A previously proposed analytical method that predicts the full CSD using inscribed circles to estimate constriction sizes is found to poorly predict the CSD for widely graded filters due to an over-idealisation of the soil fabric. The DEM data generated are used to explore quantitatively the influence of the coefficient of uniformity, particle size distribution and relative density of the filter on the CSD. For a given relative density CSDs form a narrow band of similarly shaped curves when normalised by characteristic filter diameters. This lends support to the practical use of characteristic diameters to assess filter retention capability

Otimização e validação de método para determinação de ácidos orgânicos em vinhos por cromatografia líquida de alta eficiência.

Reagentes e soluções analíticas; Instrumentação e condição cromatográfica; Estabilidade dos padrões analíticos e da fase móvel; Validação do método; Preparação das amostras de vinho