Uncertainty-Aware Organ Classification for Surgical Data Science Applications in Laparoscopy

Objective: Surgical data science is evolving into a research field that aims to observe everything occurring within and around the treatment process to provide situation-aware data-driven assistance. In the context of endoscopic video analysis, the accurate classification of organs in the field of view of the camera proffers a technical challenge. Herein, we propose a new approach to anatomical structure classification and image tagging that features an intrinsic measure of confidence to estimate its own performance with high reliability and which can be applied to both RGB and multispectral imaging (MI) data. Methods: Organ recognition is performed using a superpixel classification strategy based on textural and reflectance information. Classification confidence is estimated by analyzing the dispersion of class probabilities. Assessment of the proposed technology is performed through a comprehensive in vivo study with seven pigs. Results: When applied to image tagging, mean accuracy in our experiments increased from 65% (RGB) and 80% (MI) to 90% (RGB) and 96% (MI) with the confidence measure. Conclusion: Results showed that the confidence measure had a significant influence on the classification accuracy, and MI data are better suited for anatomical structure labeling than RGB data. Significance: This work significantly enhances the state of art in automatic labeling of endoscopic videos by introducing the use of the confidence metric, and by being the first study to use MI data for in vivo laparoscopic tissue classification. The data of our experiments will be released as the first in vivo MI dataset upon publication of this paper.Comment: 7 pages, 6 images, 2 table

Desempenho de borregos desmamados da raça Barriga Negra em Roraima.

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First passages in bounded domains: When is the mean first passage time meaningful?

We study the first passage statistics to adsorbing boundaries of a Brownian motion in bounded two-dimensional domains of different shapes and configurations of the adsorbing and reflecting boundaries. From extensive numerical analysis we obtain the probability P(\omega) distribution of the random variable \omega=\tau_1/(\tau_1+\tau_2), which is a measure for how similar the first passage times \tau_1 and \tau_2 are of two independent realisations of a Brownian walk starting at the same location. We construct a chart for each domain, determining whether P(\omega) represents a unimodal, bell-shaped form, or a bimodal, M-shaped behaviour. While in the former case the mean first passage time (MFPT) is a valid characteristic of the first passage behaviour, in the latter case it is an insufficient measure for the process. Strikingly we find a distinct turnover between the two modes of P(\omega), characteristic for the domain shape and the respective location of absorbing and reflective boundaries. Our results demonstrate that large fluctuations of the first passage times may occur frequently in two-dimensional domains, rendering quite vague the general use of the MFPT as a robust measure of the actual behaviour even in bounded domains, in which all moments of the first passage distribution exist.Comment: 9 pages, 6 figure

Processamento mínimo de mini beterraba.

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Oferta e demanda de produtos agrícolas no Brasil 2008 a 2012.

Este trabalho objetiva determinar e comparar as taxas de crescimento da demanda e da oferta internas de produtos agrícolas no Brasil, e, a partir daí, estimar quantidades demandadas e ofertadas em 2008 e em 2012, considerando para isso três cenários econômicos. Os resultados mostrarão que apenas o arroz e a carne bovina apresentam taxa de crescimento da demanda superior à da oferta e, em 2012, a demanda de carne bovina superará a oferta em termos absolutos: isso em um cenário positivo de 5% de crescimento do Produto Interno Bruto (PIB). À exceção do feijão, pode-se dizer que os demais produtos, em especial os voltados à exportação, como as carnes bovina, suína e de frango, responderam positivamente a elevações na renda. No caso desses últimos dois produtos, os fatores determinantes da oferta, tais como maiores investimentos em pesquisa e melhores preços externos, foram muito mais eficazes para imprimir um maior crescimento que os fatores determinantes de sua demanda

Suprimento de nutrientes para a produção orgânica de arroz irrigado.

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Manual para o desenvolvimento do perfil sensorial para bebida de café torrado e moído.

Procedimento: seleção de provadores; desenvolvimento da terminologia sensorial; definição das escalas; treinamento dos provadores; avaliação do desempenho dos provadores; avaliação dos produtos; análise dos resultados. Exemplo de um perfil já desenvolvido.bitstream/item/34364/1/1999-DOC-0039.pd