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Castaneda C.E.,University of Guadalajara | Esquivel P.,Technological Institute of Tepic
Neural Networks | Year: 2012

A time-varying learning algorithm for recurrent high order neural network in order to identify and control nonlinear systems which integrates the use of a statistical framework is proposed. The learning algorithm is based in the extended Kalman filter, where the associated state and measurement noises covariance matrices are composed by the coupled variance between the plant states. The formulation allows identification of interactions associate between plant state and the neural convergence. Furthermore, a sliding window-based method for dynamical modeling of nonstationary systems is presented to improve the neural identification in the proposed methodology. The efficiency and accuracy of the proposed method is assessed to a five degree of freedom (DOF) robot manipulator where based on the time-varying neural identifier model, the decentralized discrete-time block control and sliding mode techniques are used to design independent controllers and develop the trajectory tracking for each DOF. © 2012 Elsevier Ltd.

Camelo-Mendez G.A.,National Polytechnic Institute of Mexico | Ragazzo-Sanchez J.A.,Technological Institute of Tepic | Jimenez-Aparicio A.R.,National Polytechnic Institute of Mexico | Vanegas-Espinoza P.E.,National Polytechnic Institute of Mexico | And 2 more authors.
Plant Foods for Human Nutrition | Year: 2013

Anthocyanins are a group of water-soluble pigments that provide red, purple or blue color to the leaves, flowers, and fruits. In addition, benefits have been attributed to hypertension and cardiovascular diseases. This study compared the content of total anthocyanins and volatile compounds in aqueous and ethanolic extracts of four varieties of Mexican roselle, with different levels of pigmentation. The multivariable analysis of categorical data demonstrated that ethanol was the best solvent for the extraction of both anthocyanins and volatile compounds. The concentration of anthocyanin in pigmented varieties ranged from 17.3 to 32.2 mg of cyanidin 3-glucoside/g dry weight, while volatile compounds analysis showed that geraniol was the main compound in extracts from the four varieties. The principal component analysis (PCA) allowed description of results with 77.38 % of variance establishing a clear grouping for each variety in addition to similarities among some of these varieties. These results were validated by the confusion matrix obtained in the classification by the factorial discriminate analysis (FDA); it can be useful for roselle varieties classification. Small differences in anthocyanin and volatile compounds content could be detected, and it may be of interest for the food industry in order to classify a new individual into one of several groups using different variables at once. © 2013 Springer Science+Business Media New York.

Esquivel P.,Technological Institute of Tepic | Castaneda C.E.,University of Guadalajara
Electric Power Systems Research | Year: 2014

Detection and characterization of the dynamic phenomena that arise when the power system is subjected to a perturbation become a significant problem. Therefore, a great deal of attention has been paid to identify oscillatory activity in interconnected power systems through the use of wide-area monitoring schemes. This paper presents a method for detection of propagation features from wide-area system measurements through its traveling and standing components, exploring the relationship between complex modes and the wave motion. The method consists in a biorthogonal decomposition considered from a statistical perspective which has the potential to be applied for wide-area monitoring and analysis using real-time synchronized measurements recorded from power systems. Although the technique is general, data obtained from global positioning system (GPS)-based multiple phasor measurement units (PMUs) from a real event in power systems are used to examine the potential usefulness of the proposed methodology. Furthermore, the decomposition technique based on optimal persistent patterns (OPPs) for time-varying fields is used to validate the applicability of the method. © 2014 Elsevier B.V.

Quiros-Sauceda A.E.,Research Center en Alimentacion y Desarrollo | Palafox-Carlos H.,Research Center en Alimentacion y Desarrollo | Sayago-Ayerdi S.G.,Technological Institute of Tepic | Ayala-Zavala J.F.,Research Center en Alimentacion y Desarrollo | And 5 more authors.
Food and Function | Year: 2014

Dietary fiber and phenolic compounds are two recognized dietary factors responsible for potential effects on human health; therefore, they have been widely used to increase functionality of some foods. This paper focuses on showing the use of both substances as functional ingredients for enriching foods, and at the same time, describes the use of a single material that combines the properties of the two types of substances. The last part of the work describes some facts related to the interaction between dietary fiber and phenolic compounds, which could affect the bioaccessibility and absorption of phenolics in the gut. In this sense, the purpose of the present review is to compile and analyze evidence relating to the use of dietary fiber and phenolic compounds to enhance technological and nutritional properties of foods and hypothesize some of the possible effects in the gut after their ingestion. © 2014 the Partner Organisations.

de Lourdes Garcia-Magana M.,Technological Institute of Tepic | Garcia H.S.,Instituto Tecnologico De Veracruz | Bello-Perez L.A.,National Polytechnic Institute of Mexico | Sayago-Ayerdi S.G.,Technological Institute of Tepic | de Oca M.M.-M.,Technological Institute of Tepic
Plant Foods for Human Nutrition | Year: 2013

Several reports have focused on utilization of post-harvest residues of crops, while neglecting those residues produced by mango processing. These residues represent a waste of nutrients and a source of environmental contaminants. Such by-products could be valuable sources of dietary fiber (DF), antioxidant compounds, and single carbohydrates. The aim of this study was to evaluate some functional properties (FP), and the content of DF and polyphenols (PP) of the peel and coarse material obtained from residues during the industrial processing of Ataulfo and Tommy Atkins mangoes. The total dietary fiber (TDF) content was about 225 mg/g and 387 mg/g (dry weight) for the coarse material and the peel, respectively, from which soluble dietary fiber represented 23 and 42 %, respectively. The main neutral sugar identified was rhamnose, especially in peels; the klason lignin (KL) content was 92 mg/g, which highlights the Ataulfo peel (Ataulfo-P) and the Tommy Atkins peel (Tommy Atkins-P). The extractable PP content in Ataulfo-P was higher than in Tommy-Atkins-P, and interesting data for non-extractable PP were obtained in the residues. FP as swelling, water holding, oil holding, and glucose absorption in the residues was studied, obtaining better functional properties when compared to cellulose fiber. The results show that mango industrial by-products, mainly from the Ataulfo-P variety, could be used as ingredients in food products because of their functional properties as well as their DF and PP content. © 2013 Springer Science+Business Media New York.

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