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Mexico City, Mexico

Riera F.A.,University of Oviedo | Suarez A.,University of Oviedo | Muro C.,Technological Institute of Toluca
Desalination | Year: 2013

The large consumption of water in the dairy industry makes water reuse a crucial issue. Flash Cooler (FC) condensates from direct ultra high temperature (UHT) treatments were characterised and nanofiltered in order to obtain potentially reusable water depending on the limitations of its end uses. A nanofiltration (NF) pilot plant (1.6m2 membrane area) with a SelRO MPS-34 2540 B2X (Koch Membrane Systems) was used for these purposes. The influence of operating conditions (transmembrane pressure (TMP), temperature, time and water recovery) on permeate flow rate (J) and quality (conductivity, chemical oxygen demand (COD), total organic carbon (TOC) and Ca2+) was studied. Heating (taking into account the thermal potential of condensates) and other miscellaneous objectives were achieved, a volume concentration ratio (VCR) of 8 being set as a design parameter. The experimental data was used to design a NF plant with 20m3/h feed capacity whose savings and operating costs were estimated at 2.807 and 0.777€/m3, respectively. © 2012 Elsevier B.V.

Benitez Y.I.S.,Technological Institute of Toluca | Ben-Othman J.,University of Paris 13 | Claude J.-P.,University of Versailles
2014 IEEE International Conference on Communications, ICC 2014 | Year: 2014

In this paper, we have proposed the IBE-RAOLSR and ECDSA-RAOLSR protocols for WMNs (Wireless Mesh Networks), which contributes to security routing protocols. We have implemented the IBE (Identity Based Encryption) and ECDSA (Elliptic Curve Digital Signature Algorithm) methods to secure messages in RAOLSR (Radio Aware Optimized Link State Routing), namely TC (Topology Control) and Hello messages. We then compare the ECDSA-based RAOLSR with IBE-based RAOLSR protocols. This study shows the great benefits of the IBE technique in securing RAOLSR protocol for WMNs. Through extensive ns-3 (Network Simulator-3) simulations, results have shown that the IBE-RAOLSR outperforms the ECDSA-RAOLSR in terms of overhead and delay. Simulation results show that the utilize of the IBE-based RAOLSR provides a greater level of security with light overhead. © 2014 IEEE.

Urista C.M.,Technological Institute of Toluca | Jimenez J.E.,Technological Institute of Toluca | Nava M.C.D.,Technological Institute of Toluca | Arce R.E.Z.,Technological Institute of Toluca | And 2 more authors.
Chemical Engineering Communications | Year: 2013

Two ultrafiltration membranes with different geometries (spiral polymeric and tubular ceramic) but similar cutoffs were used to treat wastewater from a food industry. Hydrodynamic conditions were optimized by statistical methods as a strategy to get more accurate values of the critical parameters and then to produce higher water flux and minimization of membrane fouling. The validation of the optimization method was obtained by experimental critical flux determination at critical parameters. Membrane fluxes revealed significant differences during filtration. The polymeric membrane showed an optimal flux of 45.60 Lh -1 m -2 at 3.21 bar while operating at a stable time of 11.61 h, whereas optimal flux of the ceramic membrane was 32.43 Lh -1m -2 at 3.98 bar for 16.03 h. Experimental critical flux values were only slightly lower than optimal fluxes for both membranes, showing the validity of the statistics models applied. Negligible osmotic pressure was found on the two membranes at critical flux parameters, indicating irreversible fouling for both cases. The polymeric membrane revealed strong fouling behavior and the ceramic membrane showed a weak form; the flux decline occurred first in the polymeric membrane, whereas the ceramic membrane exhibited high stability during the filtration operations. A high degree of purification of wastewater was obtained by this membrane at critical flux conditions. © 2013 Copyright Taylor and Francis Group, LLC.

Segovia J.A.,National Institute of Nuclear Research ININ | Segovia J.A.,Technological Institute of Toluca | Contreras A.,Technological Institute of Toluca | Garduno M.P.,Technological Institute of Toluca
WSEAS Transactions on Systems | Year: 2010

Herein are presented in detail the tasks that were developed to carry out a project that had as aim updating and improving the perception system of a Pioneer 3-AT mobile robot to enhance its navigation control by means of a mechanical system to let a laser range finder scanning and acquiring 2.5D and 3D images of the robot's environment. The system developed is a mechanism that is able to put in start position and to tilt automatically a laser range finder LMS200 with high precision, because the range of repetitive accuracy is very important to get good images. This precision was obtained with the aid of different parts that work together and with the best performance into its correspondent area; electronic area (control and communication circuits), mechanical area (stepper motor and mechanical design) and informatics area (acquisition and data processing). The system was developed to be an inexpensive device, using the most common elements, as a Microchip's microcontroller, which are easy to program and there are many models to choose the one that could fit our needs and budget, small elements and many job features, for example the PWM module, communication ports by USART and USB, and A/D channels, very important characteristics to control a stepper motor.

Sierra Solache R.E.,Technological Institute of Toluca | Muro-Urista C.,Technological Institute of Toluca | Elena Ortega Aguilar R.,Technological Institute of Toluca | Arana Cuenca A.,Polytechnic University of Pachuca | Tellez Jurado A.,Polytechnic University of Pachuca
Desalination and Water Treatment | Year: 2015

Depuration capacity of immobilized Phanerochaete chrysosporium was tested on food effluents which showed high COD, sugar, and nitrogen concentration. Comparative study in airlift reactor and agitated flasks was performed to determine an effective depuration treatment with suspended and immobilized biomass into alginate spheres. While enzymetic production was analyzed in these sytems in order to evaluate influence of the immobilization micro-organism, effluent composition, and aeration mechanism. In addition, the use of seed lettuce allowed evaluating the quality and effectiveness of the studied effluent treatment system. In particular, all tests showed that COD and color of the effluent was reduced by airlift cultures. Treatment achieved a decline in 85% of COD in 120 h. While experiments with 33 PCU color showed high efficiency (100%) in decolourization period of 5 h. Maximum laccase production was mainly found in airlift system with suspended biomass, whereas manganese peroxidase was detected on immobilized micro-organism. Toxicity tests revealed that treated food effluent was not phytotoxic; conversely effluent contains sufficiently high concentrations of nutrients to ensure the germination and lettuce growth. © 2015 Balaban Desalination Publications. All rights reserved.

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