• Relationship between physical and acoustical parameters for road surface characterization

      Leos Suárez, Jesús Rodrigo
      An acoustic system for automated road surface conditions detection from acoustic signals of surface interaction is introduced. The aim of this work is to obtain different characteristics of the roadway surface by which the vehicle is circulating, to analyze its texture, friction and other characteristics related to the road surface with anticipation so that this information could be used in future automotive safety applications. The advantages of using an acoustic device compared with other current technologies is the low cost of the equipment and its portability. The robustness of our approach is evaluated on audio that span an extensive range of vehicle speeds, noises from the environment, road surface types, and pavement conditions including international friction index (IFI) values from 0 km/hr to 100 km/hr. The training and evaluation of the model were performed on different roads to minimize the impact of environment and other external factors on the accuracy of the classification. The results showed that there is a correlation between what we measured with the mechanical systems and what we obtained as a reply from the acoustic system. The hypothesis is that with the application of an acoustic device that characterizes the pavement in real time, future automotive applications such as adjusting the ABS system automatically in an optimal range of braking, showing a warning indicator light on the dashboard, or improving the driving decision making of autonomous cars will be possible by having prior information of the slippery surface conditions in which the vehicle transits.
    • Métodos heurísticos para el problema de asignación de trabajadores y balanceo de líneas de ensamblaje

      Ramos Torres, Lucía Anabel
      Some types of distribution in assembly lines of manufacturing process begin as an assembly balancing problem of a certain type. In this work we propose two different algorithms based on two different methods to find a solution to the ALWABP (Assembly Line and Worker Assignment Balancing Problem) which is a generalization of the simple assembly line problem where workers assignment is introduced as a new problem for the balancing problem. Task times in this problem depends on each worker and in some cases one worker will not be capable of perform some task. The first method developed in this work is based on a GRASP metaheuristic combined with a VND metaheuristic as part of the first one. The second method is based on a Matheuristic combining a metaheuristic with an exact method. The experimental results shown in this paper are promising for the second model, due to the improvement obtained in the objective function value, in many of the instances evaluated of the different families. Therefore, the proposed model is competitive and efficient in comparison to previous methods found in the literature and exact approaches for this problem.
    • The influence of pH in the kinetic characterization of thermophilic β-fructosidase from T. maritima

      Cruz Maldonado, Juan Jesús
      Given their advantageous features such as high reaction rates, increased specificity and negligible by-products generations, enzyme-catalyzed reactions are keep gaining ground over conventional chemical process. However, only a small fraction of currently known enzymes, is used in commercial processes at a large scale. Catalytic efficiency and stability reduction at drastic process conditions are some of the factors that restrain large scale biocatalysis boom. This can be exemplified in the industrial hydrolysis of sucrose where, at process conditions, S. cerevisiae β-fructosidase (BfrA) is subjected to thermal denaturation and substrate inhibition. In this regard, kinetic characterization of a thermophilic BfrA could help to overcome these inconveniences. Therefore, the main objective of this study is the kinetic characterization of T. maritima BfrA through a mathematical model that accounts for the simultaneous effects of pH and substrate inhibition over catalytic activity and kinetic parameters. Fitting of proposed model to experimental data yielded a surface of response which confirmed substrate uncompetitive inhibition at 146 mM of sucrose and optimum pH interval between 4.5 and 5.5. Estimation of kinetic parameters showed that Km and Ki are slightly pH dependent while vmax demonstrated to be sensitive to pH shifts. Likewise, estimated ionization constants of 3.0 and 6.60 suggested side-chain carboxylic groups of nucleophilic Asp and general acid/base Glu, which agreed with previous structural and mechanistic studies of T. maritima BfrA. These results suggest that the proposed model provide good estimations with respect of expected enzymatic activity of T. maritima BfrA at different conditions of pH and sucrose concentrations. Hence, can be useful for further kinetic characterization studies with potential application in biocatalysis process design.
    • GPGPU workload characterization using memory bottleneck detection and hierarchical clustering analysis

      Freire Bermudez, Luis Alberto
      The use of Graphic Processing Units (GPU) for General Computing (GPGPU) has become increasingly common in recent years. In this type of processor, memory bottlenecks are a critical issue and the way data are commissioned to the partitions can cause several requests to get stalled behind each other, waiting for resources. In this thesis, a methodology to characterize GPGPU kernels based on their likeability to create bottlenecks in the GPGPU memory hierarchy is presented. A GPGPU simulator is used to obtain unique fingerprints from more than 100 workloads and classify them using a Hierarchical Clustering Analysis. The thesis also shows that that optimizations made to the kernels impact its run time memory bottleneck generation and that this behavior is successfully detected by the methodology. Two major groups of kernels were defined, naïve and optimized ones, and to characterize a set of exploration kernels within those groups with an effectiveness rate of over 75% for the two groups. A discussion is also held about how different levels of optimizations can be identified by our clustering engine and how those results could be use by subsequent approaches to predict bottleneck related issues in new kernels added to the cluster. Overall, a simple and transparent methodology to study bottleneck generation on GPGPU kernels is proposed which proves useful for future applications like static chararacterizer and statics predictor.
    • Wind Farm Integration Through VSC-HVDC

      Linares Sanchez, Cristian Pool
      High Voltage Direct Current (HVDC) systems has been an alternative method of transmitting electric power from one location to another with some inherent advantages over AC transmission systems. The efficiency and rated power carrying capacity of direct current transmission lines highly depends on the converter used in transforming the current from one form to another (AC to DC and vice versa). A well-configured converter reduces harmonics, increases power transfer capabilities, and reliability in that it offers high tolerance to fault along the line. Different HVDC converter topologies have been proposed, built and utilized all over the world. The two dominant types are the line-commutated converter (LCC) and the voltage-source converter (VSC). This thesis is focused on explaining the basic concepts of HVDC Systems and their usefulness for the integration of renewable energy. With the improvement in VSC technology and the advantages which it offers over LCC, VSC is bound to grow, and gain more recognition and market share, especially with the large-scale renewable energy integration into traditional AC power grids going on worldwide. Wind energy also has matured to a level of development at which it is ready to become a generally accepted power generation technology. This thesis provides a state of the art in the area of electrical machines and power-electronic systems for high-power wind energy generation applications. Wind power is considered as the most promising renewable energy and has been under extensive development globally.
    • Disminución de consumo de diesél en generadores eléctricos para equipo de telefonía celular, aplicando un sistema de energía solar

      Viedas, Heriberto; Rodriguez, Melany Marien; Lara, Héctor Samuel
      El uso eficiente de los combustibles ha sido un reto durante años, esto ha llevado a diferentes organizaciones a tomar medidas y estudiar las posibilidades para disminuir su uso o incluso intentar prescindir de ellos al máximo implementando nuevas tecnologías. El proyecto que se analiza está basado en un problema de más de 10 años con referencia al consumo de Diesel en generadores de uso continuo en sitios con equipos de radiocomunicación, esto debido a la falta de red eléctrica comercial y la necesidad de mantener conectados las 24 horas a los usuarios de telefonía celular. Este problema implica un gasto importante que cada día va en aumento, derivado del incremento en el costo de los hidrocarburos. En este proyecto se propone reducir el impacto económico a un nivel del 30% o más por medio de la implementación de un sistema solar fotovoltaico en combinación con el generador Diesel actual. La importancia del proyecto radica principalmente en la reducción de un gasto fijo elevado que puede ser disminuido o evitado, presentando así una solución viable y atractiva a la organización.
    • Optimización del diseño de herramienta multivariable para fresado de alto rendimiento.

      Escalera, Oscar Jesus
      El objetivo de este trabajo de investigación ha sido el desarrollo de una metodología para optimizar el diseño de una herramienta de corte multivariable (con ángulos de paso y ángulos de hélice variable) mediante la implementación de un algoritmo de optimización. Se implementa un algoritmo sistemático para lograr identificar dentro de un catalogo de configuraciones de 934 mil herramientas, y con la adaptación del algoritmo del recocido simulado para maximizar la tasa de remoción de material mmr en conjunto con el algoritmo de estabilidad, y con el algoritmo de selección de herramienta mencionado se encuentran los parámetros óptimos de la herramienta multivariable. Simultáneamente se emplea una metodología analítico-numérica para la solución del problema de estabilidad de ecuaciones diferencial con retardo (DDE) que modela el proceso de corte en fresado que determina la productividad de la herramienta. Una principal contribución es la expansión de la metodología para solución de DDE mediante un enfoque de discretización del retardo y una aproximación al subintervalo de retardo con una función polinomial de segundo orden comparando mediante estudios de convergencia con una función polinomial de cero y primer orden respectivamente, teniendo a la ecuación de Mathieu y a la ecuación de fresado de un grado de libertad como casos de estudio. Esta misma solución fue empleada para forma un mapa discreto para aproximar la matriz de transición, que de acuerdo con la teoría de Floquet, contiene la información para determinar la estabilidad del sistema dinámico. La prueba de orden de precisión del método numérico para las aproximaciones de primero y segundo orden son descritas como parte del análisis de convergencia de las soluciones para ambos casos de estudio. Las validaciones experimentales de los ensayos de caracterización de la herramienta fabricada se comparan con el modelo predictivo propuesto, similarmente se validan experimentalmente algunos puntos en zonas estables e inestables comparando con el diagrama de estabilidad para la herramienta propuesta.
    • Technical and economic evaluation for two process alternatives of CO2 mineralization technology using electric arc furnace slag as raw material

      Martínez García, Diana Edith
      Carbon dioxide is the major recognized cause of climate change because of its greenhouse properties and continuous accumulation in the atmosphere. It has become attractive for industries that emits great amounts of CO2 emissions to the atmosphere the application of Carbon Dioxide Utilization (CDU) technologies in their processes. In this thesis, technical, economic and environmental aspects are presented to conceptualize two pilot plants that utilize two waste materials, one being the Electric Arc Furnace (EAF) slag produced during steel making and two the CO2 removed in a Direct Reduction (DR) plant to produce either Light Weight Aggregate (LWA) for the construction industry or Precipitated Calcium Carbonate (PCC) for the chemical industry. The objective of the research reported was to evaluate the feasibility for the implementation of the CDU processes in an integrated steelmaking facility which includes a Direct Reduction plant.
    • Syntaxin 11 regulates platelet granule release and hemostasis

      González Delgado, Ricardo
      Degranulation, a form of regulated exocytosis, is essential for platelet participation in hemostasis. The interaction between Syntaxin (Stx) and Munc18 proteins is required for exocytosis. We have proven that selective genetic deletion of Munc18-2 eliminates regulated exocytosis in platelets, but its Stx partner was not known. Among the exocytic Stx (1A, 1B, 2, 3, 4, and 11), we proved that Stxs1A, 1B, and 3 are not expressed platelets. Others have shown that deletion of Stx2 and 4 had no consequences on platelet degranulation. Now our goal is to study if Stx11 is involved in platelet exocytosis. We created a Stx11 conditional knockout mouse and crossed it with a platelet-specific Cre mouse to generate cell-specific Stx11 deletants. We evaluated the exocytosis of individual subpopulations of platelet granules stimulated with thrombin or collagen. Platelets lacking Stx11 had a marked decrease in dense granule exocytosis with both agonists, but alpha and lysosomal granules were only affected when thrombin was used. Stx11-deficient platelets had no deficiency in granule biogenesis and were capable of undergoing full activation. Platelets from Stx11 deletant mice had deficient aggregation and ex vivo thrombus formation. In vivo, all these defects translated into protection from arterial thrombosis, and in abnormal hemostasis after venous and arterial injury, in mice lacking Stx11 in their platelets.
    • Estudio de niveles de eficiencia en transformadores de distribución en función del perfil de carga

      Saldívar Hinojosa, Juan José
      La tesis presenta una visión general de las pérdidas en vacío y con carga del transformador de distribución, el potencial de ahorro, las opciones tecnológicas para la mejora, y una comparación de algunos programas de eficiencia a nivel mundial. Va dirigida al personal de la industria que trabaja en el desarrollo de programas de ahorro de energía en el mercado eléctrico mexicano. Después de las líneas de transmisión y distribución, los transformadores representan la siguiente fuente de pérdidas en la red eléctrica. Se estiman ahorros sustanciales si se adoptan regulaciones que establezcan mejores niveles de eficiencia en los transformadores instalados. La propuesta pretende definir la capacidad óptima de los transformadores en función del perfil de carga, las pérdidas asociadas y el costo inicial de los equipos así mismo pretende establecer métodos para determinar la capacidad y la eficiencia requerida en los transformadores de distribución según su aplicación.
    • Intelligent input dimensionality reduction for thermographic computer-assisted breast cancer detection

      Casar Berazaluce, Alejandro
      While traditional breast cancer thermography consists of a bidimensional image of the breast area, this study explores the possibility of reducing the size of the thermal input required by thermography to the temperature at only a few points in the breasts. That kind of information could be retrieved by locating temperature sensors around the breast, which could mean a wearable breast cancer detection implementation. In order to do this, the document first briefly summarizes and explains the methodologies used by different authors in order to implement computer-assisted thermography. Then it proposes a topological framework used to translate thermal images into a subset of points that represent what a wearable device that meets certain physical constraints would look like. This is implemented by using thermal images from 167 patients, extracting the temperature by software at 120 proposed sensor locations, 60 on each breast, and storing it in the new proposed representation. This new framework is then used to compare the methodologies used by authors in previous works, but now all under the reduced-data representation, and all using the same patient database. After finding out which kind of data representation leads to better cancer detection, the work then proceeds to use greedy search algorithms to find the subset of sensors that maximizes the predictive power of a cancer detection classifier. After the experiments, an accuracy of 88.9% was achieved using only a subset of the temperatures at only 16 locations on each breast, and an accuracy of 90.1% was achieved when combined with some statistical and spatial features computed from the temperatures. In order to evaluate the validity of these promising results, a noise and robustness test was also carried out by introducing noise into the data and studying the effects that followed. The results of this robustness test were quite relevant as well since they showed that a backward elimination search strategy can be used to remove the most noisy-prone sensors, and a forward selection strategy could potentially be used to find an optimal sensor configuration that maximizes the predictive power of the classifier. Overall, the results from this work show that thermography with reduced dimensionality achieves performances that compete with full-image thermography, and even with mammography, with the additional advantage of being implementable through a wearable device, thus not requiring the patient to visit a hospital to perform the screening. Currently the only other portable massive self-examination method is the self breast-exploration, which yields an accuracy of around 47%, which is pretty close to being a random guess. Compared to this performance, the proposed method proves to be vastly superior. It could potentially replace self breast examination as the main first-hand portable, non-invasive and non-radiative breast cancer screening tool and provide a major breakthrough in the battle against cancer by detecting the disease in the earlier stages with a greater accuracy and consistency.
    • Implementation of a transient approach for the mass and energy balance in an electric arc furnace.

      Camacho, Alejandra
      On this work, an implementation of a transient approach for the mass and energy balance in an electric arc furnace is presented. Real operation conditions were included, such as the dynamic material and energy additions and continuous inlets and outlets. Also, several inherent phenomena were characterized, such as the melting rate of scrap, the chemical reaction mechanisms and the residence time of bubbles in the slag. With all these elements, the estimation of the distribution of mass and energy flows at any time of the “heat” process was performed. The main contributions of this work are to provide a prediction of mass and energy distribution at any time of the EAF process, and to be a guideline for a dynamic optimization model which can be useful to improve the efficiency of the furnace by operation protocol modifications, therefore, the net cost per ton of liquid steel can be reduced.
    • Preparación de fibras híbridas de composito carbono-carbono

      González Dueñas, Victor Alejandro
      El principal objetivo del presente trabajo es la preparación de un composito de carbono-carbono a base fibras de alcohol polivinílico (PVA) reforzadas por diferentes nanoestructuras de carbono mediante la técnica de forcespinning con el fin de mejorar su direccionalidad y obtener una morfología homogénea. Luego mediante un proceso de pirólisis se obtuvieron fibras de carbono, con el fin de obtener un material más atractivo al mejorar sus propiedades térmicas, eléctricas y mecánicas en aplicaciones de almacenamiento de energía. Los resultados más sobresalientes de este trabajo indican la innovación del equipo de forcespinning, al modificar la geometría del dispensador de polímero incrementando la capacidad de solución por prueba y eliminando el uso de agujas o sistemas de integración de jeringas mediante una perforación sobre la cara del dispensador que permite la deposición de las fibras en la superficie obteniendo direccionalidad, se analizaron distintas concentraciones en la solución de 5, 10, 15 y 20% w/v para determinar el parámetro de velocidad rotacional para obtener un mejor procesos de producción en comparación al equipo tradicional. Además, se observó que la incorporación de las diferentes nanoestructuras de carbono en concentraciones de 0.5% w/v - 1% w/v no modifican la viscosidad de la solución lo cual evita la modificación de parámetros del equipo. La espectroscopia infrarroja (FTIR) determino que no hay un cambio estructural en el polímero y la presencia de las nanoestructuras de carbono. La microscopía electrónica de barrido (SEM) confirmó la obtención de fibras con un diámetro final de <2.1 ± 0.3 μm para cualquiera de las diversas muestras, al se agrega cloruro de sodio (NaCl), hay una disminución en el diámetro de las fibras <1.8 ± 0.2 μm de tamaño, lo cual incrementa el área superficial del material Por voltametría cíclica (CV) se estudiaron las propiedades electroquímicas de los compositos obteniendo corrientes de 10-2 y 10-3 amperes al estabilizarse por tres semanas en el electrolito dichas corrientes son mayores a las de un capacitor de cerámico comercial por lo que mejoraría la capacidad de almacenamiento de energía en dispositivos electrónicos.
    • Visualization and machine learning techniques to support web traffic analysis

      Gómez-Herrera, Fernando
      Web Analytics (WA) services are one of the main tools that marketing experts use to measure the success of an online business. Thus, it is extremely important to have tools that support WA analysis. Nevertheless, we observed that there has not been much change in how services display traffic reports. Regarding the trustworthiness of the information, Web Analytics Services (WAS) are facing the problem that more than half of Internet traffic is Non-Human Traffic (NHT). Misleading online reports and marketing budget could be wasted because of that. Some research has been done, yet, most of the work involves intrusive methods and do not take advantage of information provided by current WAS. In the present work, we provide tools that can help the marketing expert to get better reports, to have useful visualizations, and to ensure the trustworthiness of the traffic. First, we propose a new Visualization Tool. It helps to show the website performance in terms of a preferred metric and enable us to identify potential online strategies upon that. Second, we use Machine Learning Binary Classification (BC) and One-Class Classification (OCC) to get more reliable information by identifying NHT and abnormal traffic. Then, marketing analysts could contrast NHT against their current reports. Third, we show how Pattern Extraction algorithms (like PBC4cip's miner) could help to conduct traffic analysis (once visitor segmentation is done), and to propose new strategies that may improve the online business. Later on, the patterns can be used in the Visualization Tool to analyze the traffic in detail. We confirmed the usefulness of the Visualization Tool by using it to analyze bot traffic we generated. NHT traffic shared a very similar linear navigation path, contrasted with the more complex human path. Furthermore, BC and OCC (BaggingTPMiner) worked successfully in the detection of well-known bots and abnormal traffic. We achieved a ROC AUC of 0.844 and 0.982 for each approach, respectively.
    • Bearing fault diagnosis in spindles using vibration and acoustic emission

      Tamayo, Oscar
      In modern automated manufacturing processes, machinery has become more flexible and automatic but also more susceptible to conditions in different parts like spindles. The main conditions affecting them are focused in the shaft and bearings. To successfully detect and identify each condition, methodologies based on new transforms and sensors are used in controlled environments, in order to recognize the conditions effects in vibration and sound. To detect machining conditions there are two important factors: (1) The feature extraction method and (2) the type of sensor used. In feature extraction methods reviewed, Cepstrum Pre Whitening (CPW) is remarkable useful for vibration. Its main feature is suppress the shaft speed waveform of the motor in rotational machine systems and help to detect bearing faults. The main sensor used is the accelerometers to acquire vibration, but recently acoustic emission (AE) acquired from transducers are studied to improve the diagnosis along with accelerometers. In this study, an experimental system was built to acquire vibration and AE signals from faulted bearings and a methodology based on CPW, tested for vibration signals, was applied for both type of signals to compare and enhance results on machining condition monitoring. A methodology proposed using CPW, envelope spectrum, trend removal, compression and RMS limit filters (the last two just for AE) was applied to 9 vibration and 9 AE signals taken from the experimental system with the purpose of diagnosing bearing faults in the inner race (IR), outer race(OR)androllingelement(RE)inlowfrequenciesforbothsignalsandhighfrequenciesinAE. For the 18 analyzed signals, in 5 the identification of fault components were easily made, in 12 signals the fault identification was possible; but there were peaks with similar amplitudes of the fault components and in 1 signal the identification of fault components was unsatisfactory because there was no peak that matches the bearing fault frequencies. The comparison between vibration and AE showed that in 6 from 9 tests, vibration have a better result diagnosing bearing faults than AE, specifically in the IR and RE, for the remaining 3 tests that correspond to OR, AE have a better result than vibration. Finally, the high frequencies in AE revealed that just RE faults had high frequency components in one of the three analyzed tests that can be related to remarkable faults in the ball.
    • Sistema de tutoreo inteligente para el aprendizaje de las leyes de los exponentes

      García Villegas, Benjamín Eduardo; Benjamín Eduardo García Villegas
      El presente trabajo describe el diseño de un sistema de tutoreo inteligente para la simplificación de expresiones algebraicas mediante las cuatro Leyes de los Exponentes que se enseñan en el nivel preparatoria en el sistema Instituto Tecnológico y de Estudios Superiores de Monterrey. Presenta los conceptos y técnicas relativas a los principales módulos que conforman un sistema de tutoreo inteligente: el módulo experto, el módulo del estudiante, módulo instruccional, e interfaz de usuario. Entre las ventajas obtenidas con el desarrollo de este sistema se encuentran las siguientes: la sencillez de implementación, la capacidad de diagnosticar el desempeño del estudiante y, la capacidad de fungir como un medio para la práctica de ejercicios de simplificación de expresiones, en donde el usuario recibe retroalimentación del sistema.
    • Sistema de detección de color para la manufactura

      Lara Núñez, Héctor de Jesús; Héctor de Jesús Lara Núñez
    • Sistema de antenas distribuidas para redes inalámbricas móviles : levantamiento, diseño, aceptación, implementación, optimización y operación para edificios corporativos

      Caudillo Arias, María del Pilar; María del Pilar Caudillo Arias
      El objetivo de esta tesis es revisar las fases que se deben llevar a cabo para implementar un sistema de antenas distribuidas DAS, en base a mi experiencia propongo las siguientes: levantamiento, diseño, aceptación, implementación, optimización y operación. --Resumen hoja IV.
    • Síntesis y caracterización de materiales moleculares

      Prado de la Paz, Olga Leticia; Olga Leticia Prado de la Paz