3,177 research outputs found

    Latino Civic and Social Engagement

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    Special issue editors Bernardo Pohl, Viola Garcia and Traqina Emeka introduce the special edition of the Journal of Family Strengths

    A color-based objective quality metric for point cloud contents

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    In recent years, point clouds have gained popularity as a promising representation for volumetric contents in immersive scenarios. Standardization bodies such as MPEG have been developing new compression standards for point cloud contents to reduce the volume of data, while maintaining an acceptable level of visual quality. To do so, reliable metrics are needed in order to automatically estimate the perceptual quality of degraded point cloud contents. Whereas several objective metrics have been developed to assess the geometrical impairment of degraded point cloud contents, fewer publications have been devoted to evaluating color artifacts.In this paper, we propose new color-based objective metrics for quality evaluation of point cloud contents. Our work extracts color statistics from both reference and degraded point cloud contents, in order to assess the level of impairment. Using publicly available ground-truth data, we compare the performance of our proposed work with state-of-the-art metrics, and we demonstrate how the color metrics are able to achieve comparable results with respect to widely adopted solutions. Moreover, we combine color- and geometry-based metrics in order to provide a global quality score. The novelty of our works resides in simultaneously taking both degradation types into account, while being independent of the rendering process. Results show that our solution is able to overcome the limitations of focusing on only one type of degradation, achieving better performance with respect to current metrics

    Grid Loss: Detecting Occluded Faces

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    Detection of partially occluded objects is a challenging computer vision problem. Standard Convolutional Neural Network (CNN) detectors fail if parts of the detection window are occluded, since not every sub-part of the window is discriminative on its own. To address this issue, we propose a novel loss layer for CNNs, named grid loss, which minimizes the error rate on sub-blocks of a convolution layer independently rather than over the whole feature map. This results in parts being more discriminative on their own, enabling the detector to recover if the detection window is partially occluded. By mapping our loss layer back to a regular fully connected layer, no additional computational cost is incurred at runtime compared to standard CNNs. We demonstrate our method for face detection on several public face detection benchmarks and show that our method outperforms regular CNNs, is suitable for realtime applications and achieves state-of-the-art performance.Comment: accepted to ECCV 201

    Design of a transverse flux machine for power generation from seawaves

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    In this paper, we present a transverse flux linear generator. We investigate the possibility to use this generator to extract energy from seawaves. We propose an optimization procedure that allows us to obtain an optimized design of the generator. The optimized design of the converter shows a power generation capability index much higher than other renewable systems

    Temporal Interpolation of Dynamic Digital Humans using Convolutional Neural Networks

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    In recent years, there has been an increased interest in point cloud representation for visualizing digital humans in cross reality. However, due to their voluminous size, point clouds require high bandwidth to be transmitted. In this paper, we propose a temporal interpolation architecture capable of increasing the temporal resolution of dynamic digital humans, represented using point clouds. With this technique, bandwidth savings can be achieved by transmitting dynamic point clouds in a lower temporal resolution, and recreating a higher temporal resolution on the receiving side. Our interpolation architecture works by first downsampling the point clouds to a lower spatial resolution, then estimating scene flow using a newly designed neural network architecture, and finally upsampling the result back to the original spatial resolution. To improve the smoothness of the results, we additionally apply a novel technique called neighbour snapping. To be able to train and test our newly designed network, we created a synthetic point cloud data set of animated human bodies. Results from the evaluation of our architecture through a small-scale user study show the benefits of our method with respect to the state of the art in scene flow estimation for point clouds. Moreover, correlation between our user study and existing objective quality metrics confirm the need for new metrics to accurately predict the visual quality of point cloud contents

    A checklist of the helminth parasites of marine mammals from Argentina

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    Based on published records and new data accumulated by the authors, we generated a list of the helminth parasites of marine mammals from off the coast of Argentina. We found 49 reports of helminths parasitizing cetaceans and pinnipeds from Argentina from 1952 to 2015. The list includes 54 taxa of helminths (8 acanthocephalans, 24 nematodes, 11 cestodes and 11 trematodes) associated with 18 species of cetaceans and 5 species of pinnipeds. Most of the records represent adults (5 canthocephalans, 16 nematodes, 6 cestodes and 11 trematodes), followed by larvae (10 nematodes and 3 metacestodes) and juveniles (4 acanthocephalans and 2 cestodes). The checklist contains 24 named species (5 acanthocephalans, 8 nem- atodes, 4 cestodes and 7 trematodes) and 30 undetermined helminth taxa (3 acanthocephalans, 16 nematodes, 7 cestodes and 4 trematodes). The present account contains a parasite/host lists and information on the habitat, developmental stage and distribution of the parasites listed, repositories of their type and voucher specimens and references. A host-parasite list is also presented. The data compiled on the helminth of marine mammals from Argentina in the present study revealed gaps in the knowledge of their taxonomic identification, composition, distribution, host specificity and life cycles. These gaps are also briefly discussed in order to provide an outline for future research.Fil: Hernández Orts, Jesús Servando. Universidad Nacional Autónoma de México; MéxicoFil: Paso Viola, María Natalia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas; ArgentinaFil: Garcia, Nestor Anibal. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; ArgentinaFil: Crespo, Enrique Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; ArgentinaFil: González, Raul Alberto Candido. Universidad Nacional del Comahue. Instituto de Biologia Marina y Pesquera Almirante Storni; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Garcia Varela, Martin. Universidad Nacional Autónoma de México; MéxicoFil: Kuchta, Roman. Biology Centre of the Academy of Sciences of the Czech Republic; República Chec

    Ewing's sarcoma: epidemiology and prognosis for patients treated at the Pediatric Oncology Institute, IOP-GRAACC-UNIFESP

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    OBJECTIVE: To outline the epidemiological profile and prognosis for Ewing's sarcoma in the Brazilian population. Material and METHODS: The medical records of 64 patients with intraosseous Ewing's sarcoma who were treated at the Pediatric Oncology Institute, IOP-GRAACC-UNIFESP, between 1995 and 2010, were retrospectively evaluated. RESULTS: The statistical analysis on the data obtained did not correlate factors such as sex, trauma, pathological fracture and time taken for case diagnosis with the treatment outcome. Factors such as initial metastasis, lung metastasis, tumor site, age, recurrence and type of surgery showed results corroborating what has been established in the literature. CONCLUSION: The prognosis in cases of Ewing's sarcoma was mainly influenced by the presence of metastases at the time of diagnosis.OBJETIVO: Traçar o perfil epidemiológico e o prognóstico do sarcoma de Ewing na população brasileira. Material e MÉTODO: Foram avaliados, retrospectivamente, os prontuários de 64 pacientes tratados, com sarcoma de Ewing intraósseo, no Instituto de Oncologia Pediátrica, IOP-GRAACC-UNIFESP, no período de 1995 a 2010. RESULTADOS: A análise estatística dos dados obtidos não correlacionou fatores como sexo, trauma, fratura patológica e tempo ao diagnóstico com o desfecho do tratamento. Fatores como metástase inicial, metástase pulmonar, local do tumor, idade, recidiva e tipo de cirurgia indicam resultados que corroboram a literatura consagrada. CONCLUSÃO: O prognóstico no sarcoma de Ewing foi influenciado principalmente pela presença de metástase ao diagnóstico.UNIFESPUNIFESPSciEL

    Detecção de padrões espaciais na ocorrência do tripes (Thrips tabaci) na cultura da cebola

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    Onion (Allium cepa) is one of the most cultivated and consumed vegetables in Brazil and its importance is due to the large laborforce involved. One of the main pests that affect this crop is the Onion Thrips (Thrips tabaci), but the spatial distribution of this insect, although important, has not been considered in crop management recommendations, experimental planning or sampling procedures. Our purpose here is to consider statistical tools to detect and model spatial patterns of the occurrence of the onion thrips. In order to characterize the spatial distribution pattern of the Onion Thrips a survey was carried out to record the number of insects in each development phase on onion plant leaves, on different dates and sample locations, in four rural properties with neighboring farms under different infestation levels and planting methods. The Mantel randomization test proved to be a useful tool to test for spatial correlation which, when detected, was described by a mixed spatial Poisson model with a geostatistical random component and parameters allowing for a characterization of the spatial pattern, as well as the production of prediction maps of susceptibility to levels of infestation throughout the area.A cebola é uma das hortaliças mais cultivadas e consumidas no Brasil e sua importância social se deve à grande demanda por mão-de-obra. Uma das principais pragas que afeta essa cultura é o tripes do prateamento (Thrips tabaci) e sua distribuição espacial, embora importante, não tem sido considerada nas recomendações de manejo da cultura, planejamento de experimentos ou estudos amostrais. O objetivo desse artigo foi considerar métodos estatísticos para detectar e modelar padrões espaciais na ocorrência do tripes do prateamento da cebola. Para caracterizar o padrão espacial da dispersão do tripes do prateamento da cebola foi feito um levantamento anotando-se o número de insetos por fase de desenvolvimento em folhas de plantas de cebola, em diferentes datas e pontos amostrais dentro de quatro propriedades com fazendas vizinhas apresentando diferentes níveis de infestação e métodos de plantio. O teste de aleatorização de Mantel mostrou-se útil para testar a presença de padrão espacial, que quando detectado foi descrito por um modelo de Poisson misto espacial com componente aleatório geoestatístico com parâmetros que possibilititam a caracterização do padrão espacial, bem como a obtenção de mapas de predição dos níveis de susceptibilidade à infestação na área.Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES

    Spatial pattern detection modeling of thrips (Thrips tabaci) on onion fields

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    Onion (Allium cepa) is one of the most cultivated and consumed vegetables in Brazil and its importance is due to the large laborforce involved. One of the main pests that affect this crop is the Onion Thrips (Thrips tabaci), but the spatial distribution of this insect, although important, has not been considered in crop management recommendations, experimental planning or sampling procedures. Our purpose here is to consider statistical tools to detect and model spatial patterns of the occurrence of the onion thrips. In order to characterize the spatial distribution pattern of the Onion Thrips a survey was carried out to record the number of insects in each development phase on onion plant leaves, on different dates and sample locations, in four rural properties with neighboring farms under different infestation levels and planting methods. The Mantel randomization test proved to be a useful tool to test for spatial correlation which, when detected, was described by a mixed spatial Poisson model with a geostatistical random component and parameters allowing for a characterization of the spatial pattern, as well as the production of prediction maps of susceptibility to levels of infestation throughout the area.A cebola é uma das hortaliças mais cultivadas e consumidas no Brasil e sua importância social se deve à grande demanda por mão-de-obra. Uma das principais pragas que afeta essa cultura é o tripes do prateamento (Thrips tabaci) e sua distribuição espacial, embora importante, não tem sido considerada nas recomendações de manejo da cultura, planejamento de experimentos ou estudos amostrais. O objetivo desse artigo foi considerar métodos estatísticos para detectar e modelar padrões espaciais na ocorrência do tripes do prateamento da cebola. Para caracterizar o padrão espacial da dispersão do tripes do prateamento da cebola foi feito um levantamento anotando-se o número de insetos por fase de desenvolvimento em folhas de plantas de cebola, em diferentes datas e pontos amostrais dentro de quatro propriedades com fazendas vizinhas apresentando diferentes níveis de infestação e métodos de plantio. O teste de aleatorização de Mantel mostrou-se útil para testar a presença de padrão espacial, que quando detectado foi descrito por um modelo de Poisson misto espacial com componente aleatório geoestatístico com parâmetros que possibilititam a caracterização do padrão espacial, bem como a obtenção de mapas de predição dos níveis de susceptibilidade à infestação na área

    A reduced reference metric for visual quality evaluation of point cloud contents

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    Point cloud representation has seen a surge of popularity in recent years, thanks to its capability to reproduce volumetric scenes in immersive scenarios. New compression solutions for streaming of point cloud contents have been proposed, which require objective quality metrics to reliably assess the level of degradation introduced by coding and transmission distortions. In this context, reduced reference metrics aim to predict the visual quality of the transmitted contents, while requiring only a small set of features to be sent in addition to the streamed media. In this paper, we propose a reduced reference metric to predict the quality of point cloud contents under compression distortions. To do so, we extract a small set of statistical features from the reference point cloud in the geometry, color and normal vector domain, which can be used at the receiver side to assess the visual degradation of the content. Using publicly available ground-truth datasets, we compare the performance of our metric to widely-used full reference metrics. Results demonstrate that our metric is able to effectively predict the level of distortion in the degraded point cloud contents, achieving high correlation values with respect to subjective scores
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