1,298 research outputs found
Reliability prediction for structures under cyclic loads and recurring inspections
This work presents a methodology for determining the reliability of fracture control plans for structures subjected to cyclic loads. It considers the variability of the parameters involved in the problem, such as initial flaw and crack growth curve. The probability of detection (POD) curve of the field non-destructive inspection method and the condition/environment are used as important factors for structural confidence. According to classical damage tolerance analysis (DTA), inspection intervals are based on detectable crack size and crack growth rate. However, all variables have uncertainties, which makes the final result totally stochastic. The material properties, flight loads, engineering tools and even the reliability of inspection methods are subject to uncertainties which can affect significantly the final maintenance schedule. The present methodology incorporates all the uncertainties in a simulation process, such as Monte Carlo, and establishes a relationship between the reliability of the overall maintenance program and the proposed inspection interval, forming a “cascade” chart. Due to the scatter, it also defines the confidence level of the “acceptable” risk. As an example, the damage tolerance analysis (DTA) results are presented for the upper cockpit longeron splice bolt of the BAF upgraded F-5EM. In this case, two possibilities of inspection intervals were found: one that can be characterized as remote risk, with a probability of failure (integrity nonsuccess) of 1 in 10 million, per flight hour; and other as extremely improbable, with a probability of nonsuccess of 1 in 1 billion, per flight hour, according to aviation standards. These two results are compared with the classical military airplane damage tolerance requirements
Atividade inibitória de óleos fixos e essenciais no crescimento de isolados de Salmonella sp. e Salmonella typhimurium.
Neste trabalho foi avaliada a atividade antimicrobiana dos óleos essenciais de Cymbopogon wiinterianus, Pogostemon cablin, Ocimum basilicum, Ocimum gratissimum, Mentha arvensis, Eucalyptus spp., Ocimum basilicum var. Maria Bonita, Romarinus officinalis, Lippia sidoides, Cymbopogon citratus, Zingiber officinale, Azadirachta indica, Allium sativum contra Salmonella sp., e óleos de Pogostemon cablin, Ocimum basilicum var. Maria Bonita, Lippia sp., Lippia sidoides, Cymbopogon cytratus, Zingiber officinale e Ocimum gratissimum para Salmonella typhimurium
Campylobacter em cama de aviário: tratamento fermentativo e vazio entre lotes controlam a contaminação residual.
EndoAbS dataset: Endoscopic abdominal stereo image dataset for benchmarking 3D stereo reconstruction algorithms
Background: 3D reconstruction algorithms are of fundamental importance for augmented reality applications in computer-assisted surgery. However, few datasets of endoscopic stereo images with associated 3D surface references are currently openly available, preventing the proper validation of such algorithms. This work presents a new and rich dataset of endoscopic stereo images (EndoAbS dataset). Methods: The dataset includes (i) endoscopic stereo images of phantom abdominal organs, (ii) a 3D organ surface reference (RF) generated with a laser scanner and (iii) camera calibration parameters. A detailed description of the generation of the phantom and the camera–laser calibration method is also provided. Results: An estimation of the overall error in creation of the dataset is reported (camera–laser calibration error 0.43 mm) and the performance of a 3D reconstruction algorithm is evaluated using EndoAbS, resulting in an accuracy error in accordance with state-of-the-art results (<2 mm). Conclusions: The EndoAbS dataset contributes to an increase the number and variety of openly available datasets of surgical stereo images, including a highly accurate RF and different surgical conditions
EndoAbS dataset: Endoscopic abdominal stereo image dataset for benchmarking 3D stereo reconstruction algorithms
none5siembargoed_20190801Penza, Veronica; Ciullo, Andrea S.; Moccia, Sara; Mattos, Leonardo S.; De Momi, ElenaPenza, Veronica; Ciullo, Andrea S.; Moccia, Sara; Mattos, Leonardo S.; De Momi, Elen
Fenologia e crescimento de almécega no Pantanal da Nhecolândia, Mato Grosso do Sul.
Os principais eventos fenológicos de Protium heptaphyllum estão relacionados à sazonalidade da precipitação pluviométrica. A espécie apresenta potencial para estudos dendrocronológicos devido à correlação observada do crescimento diamétrico com a precipitação pluviométrica.bitstream/item/79855/1/COT83.pd
Participação da Embrapa Solos em congressos: ano 2009.
bitstream/CNPS-2010/14826/1/doc119-2009-resumos-congressos.pd
Automatic workflow for narrow-band laryngeal video stitching
In narrow band (NB) laryngeal endoscopy, the clinician usually positions the endoscope near the tissue for a correct inspection of possible vascular pattern alterations, indicative of laryngeal malignancies. The video is usually reviewed many times to refine the diagnosis, resulting in loss of time since the salient frames of the video are mixed with blurred, noisy, and redundant frames caused by the endoscope movements. The aim of this work is to provide to the clinician a unique larynx panorama, obtained through an automatic frame selection strategy to discard non-informative frames. Anisotropic diffusion filtering was exploited to lower the noise level while encouraging the selection of meaningful image features, and a feature-based stitching approach was carried out to generate the panorama. The frame selection strategy, tested on on six pathological NB endoscopic videos, was compared with standard strategies, as uniform and random sampling, showing higher performance of the subsequent stitching procedure, both visually, in terms of vascular structure preservation, and numerically, through a blur estimation metric
Seleção de espécies nativas para recuperação de áreas degradadas em propriedades rurais na Amazônia Oriental: uso de abordagem participativa.
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