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Calvo Hern andez A.,University of Salamanca | Roco J.M.M.,University of Salamanca | Medina A.,University of Salamanca | S anchez-Salas N.,Instituto Polit Ecnico Nacional
Revista Mexicana de Fisica | Year: 2014

The so-called Curzon-Ahlborn efficiency is becoming a paradigmatic result with regards to thermodynamic optimization of power cycles. Its wide applicability and sole dependence on the external heat bath temperatures (as the Carnot efficiency does) allows for an easy and fairly comparison with experimental efficiencies of striking validity. Different analytical derivations are presented in order to assess its validity and limitations for a broad variety of thermal cycles and steady state systems based on Finite-Time, Linear-Irreversible and Equilibrium Thermodynamic frameworks. Some conclusions and future perspectives are also outlined. Source


Armando M.R.,University of Poitiers | Armando M.R.,Instituto Polit Ecnico Nacional | Noel R.,University of Poitiers | Christine F.-M.,University of Poitiers
Final Program and Proceedings - IS and T/SID Color Imaging Conference | Year: 2015

Texture discrimination was the second more important task studied after colour perception and measurement. A lot of works have explored it using a separated channel processing and very few have addressed the vector aspect of this spatio-chromatic information. In this paper we propose a novel vector processing for colour texture characterization: the Colour Contrast Occurrence matrix (C2O). The C2O is expressed using a perceptual distance in the CIELab colour space and two angles characterizing the chromaticity, and darker or lighter direction of local differences. The set of local differences, the contrast occurrences, is represented in a 3D representation, offering an understandable representation of the texture variations. In this work, we analyze also the feature invariance to changes in illumination, viewpoint and spectrum of the light source. Performances in classification tasks on several texture databases show the added-value of the C2O for texture discrimination especially when the texture content becomes complex. © 2015 Society for Imaging Science and Technology. Source


Mucino V.H.,West Virginia University | Lozano Guzman A.A.,Instituto Polit Ecnico Nacional | Alcazar Farias E.K.,University Autnoma Of Quertaro | Sanchez-Goni E.,West Virginia University | Navarrete I.A.,Instituto Polit Ecnico Nacional
ASME International Mechanical Engineering Congress and Exposition, Proceedings (IMECE) | Year: 2012

Global competencies of engineering graduates have been identified as traits that are increasingly necessary for professional competitiveness of graduates, but continue to be elusive and difficult to address in the engineering curricula. Study abroad and experiential learning programs have been invoked to address some of the global competencies with varied degrees of success. In this paper, a faculty-led program model developed by West Virginia University and several institutions in Mexico and the US is presented, in which senior engineering students from the US and Mexico team up to conduct meaningful engineering projects in industry in Mexico. Intermixed teams of students are formed and placed in various industrial sites to work full time under the advice of engineering practitioners and faculty members from both Mexico and USA. Global competencies are addressed in the context of a project that requires students to work with peers of similar disciplines and level across language and cultural barriers. Copyright © 2012 by ASME. Source


Pineda-Briseno A.,Instituto Tecnologico de Matamoros | Menchaca-Mendez R.,Instituto Polit Ecnico Nacional | Lugo G.G.,Instituto Polit Ecnico Nacional
Computacion y Sistemas | Year: 2016

This work presents the first integrated framework for positioning and multicast routing in mobilead hoc networks (MANETs). In this new approach, the same control signaling is used to support multicast routing and positioning, eliminating the distinction between on-demand and proactive signaling, which are substituted by interest-driven signaling. We also present the POSTAL PRIME protocol which is an instantiation of this integrated routing and positioning framework. We use the concept of region of interest to identify connected components of the network that include sources and destinations in the case of routing, and beacons and nodes with interest in computing their position in the case of positioning. This way, we can restrict the dissemination of control signaling to these regions, augmenting the spatial reutilization of bandwidth. POSTAL PRIME also introduces the probabilistic multilateration method for estimating the position of a node based on the position of three or more references and noisy estimates of distances to them. To assess the effectiveness of POSTAL PRIME, we present a detailed simulation-based analysis. The experimental results show that POSTAL PRIME outperforms the combined use of ODMRP+Amorphous, which are the most representative multicast routing and positioning protocols in MANETs. Source


Navarrete J.A.R.,Autonomous University of Queretaro | Lozano Guzman A.A.,Instituto Polit Ecnico Nacional | Navarrete I.A.,Instituto Polit Ecnico Nacional
ASME International Mechanical Engineering Congress and Exposition, Proceedings (IMECE) | Year: 2014

In a context in which a succession of crashes involving double combination vehicles has occurred in Mexico during 2012 and 2013, a catastrophic accident occurred on May 7, 2013, burning-killing 27 people whose homes were located adjacent to the road. In this case, the double combination carried Liquefied Petroleum Gas(LPG) in both containers, the second of which exploded as a consequence of its decoupling from the vehicle and roll over. The impact of the tractor against the median barrier due to an excessive evasive maneuver sparked a first conflagration due to a fuel leakage, which supplied the heat for the warming and subsequent explosion of the rolled-over container. The cabin of the tractor-semitrailer caught fire but the driver was able to move the vehicle 500 meters away from the crash spot. The analysis suggests that several characteristics of the vehicle and infrastructure could have mitigated or prevented the catastrophic consequences of this event, along with an appropriate response from the emergency response agencies. In particular, both, a B-train vehicular configuration and a vertical barrier could have prevented the occurrence of the fatal roll over. Copyright © 2014 by ASME. Source

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