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Ciudad Lopez Mateos, Mexico

Uribe-Godinez J.,CINVESTAV | Hernandez-Castellanos R.,Technological University of Mexico | Jimenez-Sandoval O.,CINVESTAV
Journal of Power Sources

The electrocatalytic activity for oxygen reduction and hydrogen oxidation of a discrete metal carbonyl cluster with a well defined molecular and crystal structure, Rh6(CO)16, is reported. The exchange current density of this compound for oxygen reduction is one order of magnitude higher than that of platinum, and its resistance degree to PEM fuel cell contaminants such as methanol and CO is as high as 2 mol L-1 and 0.5%, respectively. These properties make the metal complex a potential alternative for use as electrode in polymer electrolyte membrane fuel cells. © 2010 Elsevier B.V. Source

Guzman-Ramirez E.,Technological University of Mexico | Garcia I.A.,Technical University of Madrid
Computer Applications in Engineering Education

Visual information plays an important role in almost all areas of our life. Today, much of this information is represented and processed digitally. Digital image processing is any form of signal processing for which the input is an image, such as a photograph or video frame; the output of image processing may be either an image or a set of characteristics or parameters related to the image. In this context, implementation and evaluation of image processing algorithms are complex tasks that require highly technical and multidisciplinary skills. Graduate students are required to develop both practical and theoretical exercises to understand how an algorithm works; however, they have to learn in an individual manner without adequate support. This article presents an innovative Project-Based Learning approach to teach image processing algorithms using an FPGA-based tool as the main support. Thus, instead of learning heavy programming tasks and mathematical functions, students are led step by step through five phases and then allowed to experiment with different algorithms. This article evaluates the proposed tool and shows results with diverse algorithms. Comput Appl Eng Educ © 2012 Wiley Periodicals, Inc. Source

Ramirez J.M.,CINVESTAV | Gonzalez J.M.,Technological University of Mexico | Ruben T.O.,Tulancingo Polytechnic University
International Journal of Electrical Power and Energy Systems

With the advent of new technology based on power electronics, power systems may attain better voltage profile. This implies the proposition of careful strategies to dispatch reactive power in order to take advantage of all reactive sources, depending on size, location, and availability. This paper proposes an optimal reactive power dispatch strategy taking care of the steady state voltage stability implications. Two power systems of the open publications are studied. Power flow analysis has been carried out, which are the initial conditions for Transient Stability (TS), Small Disturbance (SD), and Continuation Power Flow (CPF) studies. Steady state voltage stability analysis is used to verify the impact of the optimization strategy. To demonstrate the proposal, PV curves, eigenvalue analyses, and time domain simulations, are utilized. © 2010 Elsevier Inc. All rights reserved. Source

Arenas M.C.,National Autonomous University of Mexico | Andablo E.,Technological University of Mexico | Castano V.M.,National Autonomous University of Mexico
Journal of Nanoscience and Nanotechnology

Conducting polyaniline nanofibers (nf-PANI) were successfully synthesized by simple polymerization of aniline in presence of single and binary dopant agents. Strong hydrochloride acid (HCI), two weak organic acids (poly acrylic acid, PAA, 2-acrylamido-2-methyl-1-propanesulfonic acid, AMPSA) and one anionic surfactant (sodium dodecyl sulfate, SDS) were used to form the binary dopant agents. The binary dopant agent PAA modified the morphology of the single doped PANI, whereas AMPSA and SDS modified the dimensions of the nanofibers: The length size single nanofibers is reduced 1.72 times with binary-doped AMPSA and increased by a factor of 0.7 with SDS. The surface roughness of the films decreases when the dimensions of the nanofibers increase: PANI-SDS film is flatter than PANI-AMPSA film. In general, the conductivity of the single-doped PANI nanofibers (nf-PANI-HCI) was improved by one order of magnitude with binary dopant agents (HCI-PAA, HCI-AMPSA, HCI-SDS). The influence of the binary dopant agents in the nf-PANI-HCI properties is analyzed by Transmission Electron Microscope (TEM), Atomic Force Microscopy (AFM), UV-VIS absorption spectra, thermogravimetric analysis (TGA) and Fourier-Transform infrared spectra (FT-IR). Copyright © 2010 American Scientific Publishers. All rights reserved. Source

Paredes-Sanchez J.P.,University of Oviedo | Villicana-Ortiz E.,Technological University of Mexico | Xiberta-Bernat J.,University of Oviedo
Journal of Cleaner Production

The location of mining areas is subject to the availability of resources and the capability to extract them. As these areas are usually isolated or of difficult access they lack any means of electric infrastructure as its installation can be rather costly. Therefore the use of local energy resources, such as solar energy, becomes relevant for the mine energy supply. This study carries out a solar pumping project in a slate mine in Galicia (Spain) related to automatic control systems in surface water management affected by waste from the extractive activity and thus abiding with environmental legislation. © 2014 Elsevier Ltd. All rights reserved. Source

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