3,817 research outputs found

    Occlusion Coherence: Detecting and Localizing Occluded Faces

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    The presence of occluders significantly impacts object recognition accuracy. However, occlusion is typically treated as an unstructured source of noise and explicit models for occluders have lagged behind those for object appearance and shape. In this paper we describe a hierarchical deformable part model for face detection and landmark localization that explicitly models part occlusion. The proposed model structure makes it possible to augment positive training data with large numbers of synthetically occluded instances. This allows us to easily incorporate the statistics of occlusion patterns in a discriminatively trained model. We test the model on several benchmarks for landmark localization and detection including challenging new data sets featuring significant occlusion. We find that the addition of an explicit occlusion model yields a detection system that outperforms existing approaches for occluded instances while maintaining competitive accuracy in detection and landmark localization for unoccluded instances

    The estimation of genetic parameters for growth curve traits in Raeini Cashmere goat described by Gompertz model

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    The objectives of this study were to describe growth curve of Raeini Cashmere goat applying the Gompertz growth model and genetic evaluation of growth curve-related traits including model parameters of A, B and K, inflection age (IA) and inflection weight (IW) under animal model. The data used in this study, collected in Raeini Cashmere goat breeding station from 1997 to 2009 and were included 12,831 body weights records measured at birth, weaning, 6-months of age, 9-month of age and yearling of age. The Pearson’s correlation coefficient between observed and predicted body weights was 0.98, which means that Gompertz model adequately described the growth curve in Raeini Cashmere goat. The estimated value for growth curve parameters of A, B and K were 17.97, 1.97 and 0.017, respectively. The weight and age at point of inflection were 6.63 kg and 52.94 days, respectively. Direct heritability estimates for A, B, K, IA and IW were low values of 0.14, 0.10, 0.03, 0.14 and 0.14, respectively. Low estimated values for direct heritability of the studied growth curve traits in Raeini Cashmere goat indicated that direct selection for these traits may not be useful in terms of achieving genetic change. Direct genetic correlations ranged from −0.76 (K-IW) to 0.98 (A-IW). Phenotypic correlation estimates were generally lower than the direct genetic ones and ranged from −0.30 (K-IW) to 0.69 (A-B and B-IA). IA and IW had high positive phenotypic (0.86) and genetic (0.99) correlations, implying IA and IW were highly correlated in terms of phenotypic and genetic effects. The studied growth curve parameters of Raeini Cashmere goat have shown low levels of additive genetic variation.info:eu-repo/semantics/publishedVersio
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