Time filter

Source Type

Santiago de Queretaro, Mexico

Negrete-Navarrete L.E.,University of Guanajuato | Fonseca-Badillo M.A.,University of Guanajuato | Gonzalez-Parada A.,University of Guanajuato | Castaneda-Miranda A.,Polytechnic University of Queretaro
Procedia Engineering

The article presents simulation based on finite element technique of the most common faults in three-phase squirrel-cage induction motors. Faults examined in this paper are: rotor broken bars and inter-inter turns short-circuit in stator windings. Fault in rotor broken bars was simulated taking two consecutive bars to see how the flux density is affected. Inter-turn short-circuit faults was simulated taking 40% inter-turn short-circuit of the windingin one phase. Simulations were performed using finite element software FEMM to obtain the flux density waveform in the airgap and in the electromagnetic core. Results from simulations were exported to MATLAB for further process and analysis. Flux density waveforms were plotted and processed by FFT analysis to observe harmonic distribution. © 2011 Published by Elsevier Ltd. Source

Gomez-Melendez D.,Polytechnic University of Queretaro | Lopez-Lambrano A.,Autonomous University of Queretaro | Herrera-Ruiz G.,Autonomous University of Queretaro | Fuentes C.,Autonomous University of Queretaro | And 5 more authors.
African Journal of Agricultural Research

Fuzzy logic provides a methodology to represent, manipulate, and implement heuristic knowledge to control a system. In this work, the development of a fuzzy irrigation control system based on a field programmable gate array (FPGA) to control greenhouse fertigation was presented. Factors involved in crop nutrition were discussed first. Further, the description of the fuzzy control system was presented, followed by the analysis and design of the fuzzy controller, and its implementation, a FPGA-integrated circuit. The FPGA system is not only flexible (it can be easily reconfigured and reused for different designs), but it also provides rapid prototyping and offers the capability to perform multiple operations at the same time, producing positive economic returns. The design, compilation, and simulation of the system were developed in Active-hardware description language (HDL) using the hardware description language, very high-speed integrated circuit hardware description language (VHDL). Results from simulation and experiments showed the simplicity of the design, the viability of its implementation, and the low cost that the use of a fuzzy logic controller and FPGA system represents. © 2011 Academic Journals. Source

Martinez-Fuentes V.,Polytechnic University of Queretaro | Dominguez-Lopez I.,CICATA IPN Cerro Blanco 141 | Garcia-Garcia A.L.,CICATA IPN Cerro Blanco 141

Previous experimental work has shown the possibility of applying laser light scattering (LLS) methods to study the evolution of surface topography during the initial transient period in a wear experiment on a pin-on disk apparatus. A specific set up of a laser source, pointing towards anywhere on the wear-track of the pin on the disk, and a detector to sense the light scattered from the surface, located off the plane of incidence, providing an LLS signal whose changes are related to the surface damage due to the pass of the pin as it runs over the disk. When applied to monitor the surface changes during the running-in stage, the LLS signal shows a characteristic signature for each material and wear regimen. While typical surface analysis using the pin-on-disk apparatus is done ex situ, after wear took place, our experimental setup is designed to detect the minute changes suffered by the surface of the disk due to mechanical contact with the pin, showing the onset stages of wear during the initial transient, in real time. Ex situ analysis using optical microscopy (OM) and surface roughness measurements provides an insight as to the events leading to the changes in surface texture observed in LLS. © 2011 Elsevier B.V. Source

Gonzalez-Parada A.,University of Guanajuato | Espinosa-Loza F.J.,Lawrence Livermore National Laboratory | Castaneda-Miranda A.,Polytechnic University of Queretaro | Bosch-Tous R.,Polytechnic University of Catalonia | Granados-Garcia X.,CSIC - Institute of Materials Science
IEEE Transactions on Applied Superconductivity

The development of HTS superconductor motors has been focused on the traditional construction, mainly in the magnetic field in radial flux configuration like the traditional electrical motors, for this reason the design and construction of superconductor machines in axial magnetic flux configuration are a new alternative for the development of the HTS superconductor motors. In this work, calculations for design and optimization of a superconductor biphasic induction motor in axial flux configuration are presented. The motor construction was made with BSCCO-2223 tape, its respected electrical evaluation and results are presented in geometries of 4, 6, and 8 poles in an ironless stator. A wound rotor was made with BSCCO tapes in order to test within the stators superconductor developed. The optimization of rotor tests was carried out at the beginning with aluminum rotors. After that, some wound superconductor rotors were constructed on a flat squirrel cage configuration for evaluation with superconductor stators. © 2002-2011 IEEE. Source

Santillan I.,Autonomous University of Queretaro | Herrera-Navarro A.M.,Autonomous University of Queretaro | Mendiola-Santibanez J.D.,Autonomous University of Queretaro | Mendiola-Santibanez J.D.,Polytechnic University of Queretaro | Terol-Villalobos I.R.,CIDETEQ
Journal of Mathematical Imaging and Vision

This paper deals with the notion of connectivity in viscous lattices. In particular, a new family of morphological connected filters, called connected viscous filters is proposed. Connected viscous filters are completely determined by two criteria: size parameter and connectivity. The connection of these filters is defined on viscous lattices in such a way that they verify several properties of the traditionally known filters by reconstruction. Moreover, reconstruction algorithms used to implement filters by reconstruction can also be employed to implement these new filters. We also show that connected viscous filters have a behavior similar to filters with reconstruction criteria. The interest of these new connected filters is illustrated with different examples. © 2009 Springer Science+Business Media, LLC. Source

Discover hidden collaborations