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排序方式: 共有7039条查询结果,搜索用时 343 毫秒
941.
942.
Osuna-Ruiz Idalia Espinoza-Marroquin María Fernanda Salazar-Leyva Jesús Aarón Peña Emyr Álvarez-González Carlos Alfonso Bañuelos-Vargas Isaura Martínez-Montaño Emmanuel 《Food science and biotechnology》2019,28(6):1785-1793
Food Science and Biotechnology - Pepsin from stomach of Bagre panamensis was semi-purified and biochemically characterized. The acid proteolytic activity and purification fold were... 相似文献
943.
José de Jesús Nuño Ayón Julián Sotelo Castañon Carlos Alberto López de Alba 《电力部件与系统》2018,46(2):230-241
Wide-area techniques provide a powerful tool to extract spatio-temporal patterns from high-dimensional datasets and can be used for event detection and visualization, data fusion, stability assessment, and coherency analysis. In this paper, a novel blind source separation-based approach for extracting low-frequency spatio-temporal patterns from measured ambient power system data is proposed and a spatio-temporal visualization index is also suggested. This methodology combines a nonlinear hierarchical neural network with a Blind Source Separation (BSS) technique. The neural network allows reducing noise and removing the nonlinear relations among data (preserve dynamic features of interest), while the BSS technique permits extracting spatial and temporal patterns. In addition, the proposed approach takes advantage of the latest techniques in nonlinear estimation of non-stationary time series. Finally, application examples of the proposed framework on real test cases recorded from an actual power system by Phasor Measurement Units (PMUs) are presented. The obtained results show that the temporal patterns can be used for extracting and identifying the low-frequency oscillation modes and the spatial patterns can be used for identifying modes with the most contribution in original data. Compared to other BSS approaches, the proposed method has shown to be better for the analysis of real ambient data. 相似文献
944.
Roberta Valmorbida Geovana D. Savi Juliana R. Silva Monica M.O. Yanez Carlos E.S. Soares Cristina Runtzel 《Food Additives and Contaminants: Part B: Surveillance Communications》2018,11(1):54-63
The quality and safety of maize (Zea mays L.) from different grain storage units (GSUs), located in the main producing region of Rondônia State, Northern Brazil, were evaluated. Maize grains (n = 76) stored in four GSUs were collected from July to November 2014 and evaluated for grain damages, humidity, fungi and fumonisins (FBs) content. The climate conditions data were also obtained from plant growing to storage periods. Regarding the moisture content and water activity (aw), these varied from 10.0% to 16.1% and 0.5 to 0.8, respectively. As expected, fungi spores were present in 94.8% of the samples, prevailing Fusarium genera, with a fungi colony maximum of 2.2 × 104 CFU g?1. Regarding FBs, 60.5% of the samples were contaminated, below Brazilian and United States maximum limits, but 9.2% had levels higher than the European legislation. 相似文献
945.
Esteves Carlos Allen-Blanchette Christine Makadia Ameesh Daniilidis Kostas 《International Journal of Computer Vision》2020,128(3):588-600
International Journal of Computer Vision - We address the problem of 3D rotation equivariance in convolutional neural networks. 3D rotations have been a challenging nuisance in 3D classification... 相似文献
946.
Juliana M. Guedes-Oliveira Yuan H. Brad Kim Carlos A. Conte-Junior 《International Journal of Food Science & Technology》2021,56(12):6157-6170
In recent years, much attention has been paid to the consumption of meat and processed meat, and their relationship with a healthy diet. This review provides an overview of the potential strategies, which can be used to provide the implications for producing healthy, wholesome and consistently high-quality meat products. Genetic selection, nutrition and feeding management, and gene manipulation techniques have been used as the main strategies to induce beneficial changes in meat and meat composition. Besides, the incorporation of ingredients that play a technological role and are potentially health-enhancing, such as fibre, fat substitutes, natural antioxidants and the reduction of sodium and nitrites, has a high potential in the development of healthier meat products. In this review, we have observed that many strategies have been successfully used to obtain products with low fat, reduced sodium and nitrite content, low cholesterol and absence of synthetic antioxidants. Another point to be highlighted is that some of these strategies also allow obtaining products with positive health effects that can be potential alternatives to improve consumer acceptance. 相似文献
947.
Olías Manuel Cánovas Carlos R. Basallote M. Dolores 《Mine Water and the Environment》2021,40(1):235-249
Mine Water and the Environment - The failure of the tailing dam at the Aznalcóllar mine (SW Spain) in 1998 released ≈ 6 million m3 of pyrite sludge and acidic... 相似文献
948.
Juan Carlos Fortes Jos Miguel Dvila Aguasanta Miguel Sarmiento Ana Teresa Lus Mara Santisteban Jess Daz-Curie Francisco Crdoba Jos Antonio Grande 《Mine Water and the Environment》2020,39(2):195-203
Mining equipment and structural elements (e.g. bridges, mining exploration equipment), which are mainly made of steel and concrete, undergo corrosion processes that are strongly accelerated in these extremely acidic environments, with the further aid of acidophilic bacteria that act as catalysts. 相似文献
949.
Pattern Analysis and Applications - In robotic systems, both software and hardware components are equally important. However, scant attention has been devoted until now in order to detect... 相似文献
950.