UTN- FRC -Producción Académica de Investigación y Desarrollo
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Item Desarrollo de sistema de análisis de texto(Universidad Nacional de La Plata, 2017) Castillo , Julio; Cárdenas , Marina; Curti, Adrián; Casco , Osvaldo; Navarro, Martín; Hernández, Nicolás; Velazco, Melisa; Navarro, Martín; Curti, AdriánEn este proyecto se busca utilizar técnicas de aprendizaje automático para analizar y procesar textos que pueden estar en formato estructurado como no estructurado. Se han desarrollado un conjunto de herramientas que pueden ser utilizadas en el área de computación lingüística para diversos fines, entre los que se encuentran construcción de material de entrenamiento, procesamiento de datos estructurados y detección de similitudes entre fragmentos de textos. Los problemas que se abordan en este proyecto son, entre otros, reconocimiento de implicación de textos e identificación de paráfrasis. En este artículo se presenta la línea de investigación en la que se encuentra el proyecto, y se describen tres herramientas desarrolladas en el mismo.Item Creación de corpus para aplicaciones de análisis de texto no estructurado(Universidad Tecnológica Nacional Regional Córdoba., 2017) Castillo , Julio; Zea Cardenas , Milagros; Zea Cardenas , MilagrosEn este trabajo se describen dos de las aplicaciones desarrolladas para dar soporte en las actividades de elaboración de material de entrenamiento para sistemas de minería de datos sobre texto no estructurado. El desarrollo de dichas aplicaciones está motivado en la necesidad de generar y utilizar corpus que sirva en la fase de entrenamiento de técnicas de aprendizaje automático (machine learning), especialmente Redes Neuronales Artificiales (RNA), para analizar texto en lenguaje natural (por ejemplo un artículo de diario, o revista) para la identificación de paráfrasis e implicación de textos semánticamente relacionados.Item Aplicaciones de análisis de información textual: Corpus Lingüístico(Universidad Tecnológica Nacional Regional Córdoba., 2017) Castillo , Julio; Zea Cárdenas , MilagrosEn este artículo se describe un proyecto de investigación relacionado al análisis y procesamiento de información textual, tal como el reconocimiento de paráfrasis o la implicación de textos. En ese contexto se describe la creación de una herramienta para construir corpus lingüísticos que pueden ser utilizados como material de entrenamiento para sistemas de minería de datos y de extracción de información, en especial sobre texto no estructurado.Item Visual homography-based pose estimation of a quadrotor using spectral features(IEEE, 2016) Araguás , Gastón; Paz , Claudio; Pérez Paina , Gonzalo; Canali, LuisPose estimation of Unmanned Aerial Vehicles (UAV) using cameras is currently a very active task in computer and robotic vision. This is mainly because of the use of robots in GPS-denied environments. However, the use of visual information for ego-motion estimation presents several difficulties, such as features search, data association, inhomogeneous features dis tribution in the image. This work addresses these issues by the use of the so-called spectral features, and a down-looking monocular camera rigidly attached to a quadrotor. We propose a visual position and orientation estimation algorithm based on the discrete homography constraint induced by the presence of planar scenes. This homography constraint results more appropriate than the well-known epipolar constraint, which vanishes for a zero translation and loses rank in the case of planar scenes. The pose estimation algorithm is tested in a simulated dataset and compared with the corresponding ground truth.Item Preparation and characterization of activated CMK-3 modified with vanadium applied in hydrogen storage(XXIII INTERNATIONAL MATERIALS RESEARCH CONGRESS, 2014) Juárez, Juliana; Gómez Costa, Marcos; Cussa, Jorgelina; Anunziata, OscarThe aim of this work is to synthesize a nanostructured Carbon CMK-3 modified with V in order to increase its capacity in hydrogen storage. The approach that we have followed includes synthesis of nanostructures with the experimental study of its adsorption capacity and storage properties. Ordered nanoporous carbon CMK-3 was synthesized via a two-step impregnation of the SBA-15 mesopores with a solution of sucrose using an incipient wetness method. The sucrose–silica composite was heated at 1173 K for 4 h under nitrogen flow. The silica template was dissolved with 5 wt% hydrofluoric acid in order to remove the silica. The template-free carbon product thus obtained was filtered, washed with deionized water and ethanol, and dried. [1] V-CMK-3 was prepared by wetness impregnation using VCl3 as source of Vanadium in order to increase the amount of hydrogen adsorbed. The sample of V-CMK-3 was treated under H2 flow two times at 1173 K. Porous carbon CMK-3 and the sample modified with V were characterized by XRD, FTIR, XPS, BET, TEM and SEM. These studies indicate that it was possible to obtain a CMK-3 replica successfully from SBA-15, using sucrose as a carbon precursor. [2] The surface areas are 1320 m2/g and 1050 m2/g for CMK-3 and V-CMK-3, respectively. While the nanomaterial area is significantly smaller with the incorporation of the metal, CMK-3`s characteristic structure is maintained after the metal is within the host, in agreement with the XRD studies. Measurements of hydrogen adsorption at cryogenic temperatures and low pressures were performed. The nanoparticles of V incorporated onto the nanostructured carbon CMK-3 showed higher hydrogen uptake at low and high pressures than CMK-3. (3.4 wt% and 2.2 wt% respectively of H2 sorption at 10 bar and 77 K).Item Composites of polyindole nanowires within silicates and aluminosilicates hosts with distinct conductive properties(International Conference on Materials and Engineering Technology, 2015) Juárez, Juliana; Gómez Costa, Marcos; Mugas, Brenda; Anunziata, OscarNanostructured silicate SBA-15 and aluminosilicate AlSBA-15 were synthesized in order to prepare polyindole composites. The Silica mesoporous materials were prepared by sol–gel method and the alumination by post-synthesis technique, and analyzed by different methods (XRD, BET, TEM, and FTIR). Polyindole/host composites were prepared by an oxidative in situ polymerization of pre-adsorbed indole, em ploying Cl3Fe as oxidant. TG, FTIR, BET, XRD, SEM and TEM were used to characterize the resulting composites. These studies show that after polymerization, the porous structures of the materials are preserved and the Polyindole is found within the porous channels. The composites have an electrical conductivity range between higher than the pure Polyindole chemically synthesized, close to the electrical conductivity of pure polymer electrochemically synthesized, and lower than the pure polymer chemically synthesized, in order of 10-8 S/cm.Item Orientation estimation fusing a downward looking camera and inertial sensors for a hovering UAV(IEEE, 2013) Gastón, Araguás; Claudio, Paz; David, Gaydou; Gonzalo Pérez, Paina—Nowadays, a particular kind of UAVs (Unmanned Aerial Vehicle) known as quadcopters or quadrotors have become very popular. This is mainly due to their reduced size and high maneuverability which allow them to operate in indoor environments. The requirement for orientation estimation in these vehiclesistwofold: for low levelstability control, and for high level navigation and motion planning. Orientation estimation is usually carried out fusing measurements of different sensors including inertial sensor, magnetic compass, sonar, GPS, camera, etc. As is known, GPS signal is not available in indoor environments and the Earth’s magnetic field is highly disturbed by ferromagnetic structures. In the present work we describe a new approach for quadrotor orientation estimation fusing inertial measurements with a downward looking camera. Inertial sensor are used for orientation estimation based on the gravity vector, and the camera providesinformation related to the heading direction. The camera heading or yaw angle estimation is based on spectral features extracted from the floor plane. Experimental results show the performance of the presented approach applied to a hovering UAV.Item Tetralin hydrogenation over Pt-Ir/SBA-15. optimization by experimental desing.(XXIV International material research congress, 2015) Vallés, Verónica; Ledesma, Brenda; Rivoira, Lorena; Cussa, Jorgelina; Anunziata, Oscar; Beltramone, AndreaThe oil refining industry has a difficult challenge to meet the increasingly stringent regula tions on environmental issues. Contaminants such as sulfur, nitrogen, fused ring aromatic compounds or metals are the principal to remove to achieve "green" fuels. The hydrotreating (HDT) is one of the processes most used in the refinery to remove these contaminants. To optimize the gas oil hydrotreater, it is crucial to understand the aromatic hydrogenation reaction chemistry occurring in the gas oil hydrotreater. To find alternative processes, it is neces sary to develop new and more active catalysts to replace the current ones. Bimetallic Pt–Pd catalysts have received considerable attention, because they show high actvity in a variety of catalytic applications [1,2]. From a fundamental point of view, exploring bimetallic catalysts also allows better understanding of mechanisms and variables involved in the catalytic reactions. The features of the catalysts here studied are going to be correlated with their catalytic performance in the hydrogenation of tetralin. The final goal is to find the optimal proportion of each metal in order to be more active and the best reaction conditions. The statistical expe riments design is the process of planning an experiment to obtain appropriate data that can be analyzed by statistical methods, to produce concrete and valid conclusions [3]. One of the main advantages in the response curve is to visualize the response for all levels of the experi mental factors Experiment design response surface methodology (RSM) is used in this work to model and to optimize the process.Item Experimental desing optimization of the tetralin hydrogenation over Ptlr/SBA-15(International Symposium on Advances in Hydroprocessing of Oil Fractions, 2015) Valles, Verónica; Ledesma, Brenda; Rivoira, Lorena; Cussa, Jorgelina; Anunziata, Oscar; Beltramone, AndreaThe oil refining industry has a difficult challenge to meet the increasingly stringent regula tions on environmental issues. Contaminants such as sulfur, nitrogen, fused ring aromatic compounds or metals are the principal to remove to achieve "green" fuels. The hydrotreating (HDT) is one of the processes most used in the refinery to remove these contaminants. To optimize the gas oil hydrotreater, it is crucial to understand the aromatic hydrogenation reaction chemistry occurring in the gas oil hydrotreater. To find alternative processes, it is necessary to develop new and more active catalysts to replace the current ones. Bimetallic Pt–Pd catalysts have received considerable attention, because they show high actvity in a variety of catalytic applications [1,2]. From a fundamental point of view, exploring bimetallic catalysts also allows better understanding of mechanisms and variables involved in the catalytic reac tions. The features of the catalysts here studied are going to be correlated with their catalytic performance in the hydrogenation of tetralin. The final goal is to find the optimal proportion of each metal in order to be more active and the best reaction conditions. The statistical experiments design is the process of planning an experiment to obtain appropriate data that can be analyzed by statistical methods, to produce concrete and valid conclusions [3]. One of the main advantages in the response curve is to visualize the response for all levels of the experi mental factors Experiment design response surface methodology (RSM) is used in this work to model and to optimize the process.Item Sulfur elimination by oxidative desulfurization with titanium-modified SBA-16(International Symposium on Advances in Hydroprocessing of Oil Fractions, 2015) Rivoira, Lorena; Vallés, Verónica; Ledesma, Brenda; Martínez, María Laura; Anunziata, Oscar; Beltramone, AndreaOver the past, oxidative desulfurization (ODS) has drawn considerable interest as a new alternative method for deep sulfur elimination from light oils. This can be attributed to its attractive properties, including lower temperature and pressure conditions and lower operating cost [1-3] than conventional hydrodesulfurization (HDS) process. Oxidation of organosulfur compounds results in the formation of sulfoxides/sulfones, highly polar and hence easily removed by both extraction into polar solvents or by adsorption. Due to their low reactivity, dibenzothiophene derivatives (DBTs) are the most refractory species to be eliminated from oils. Hence, the ODS process through which DBTs are converted to their corresponding sulfones involves great interest at present [4-6]. We recently reported a good performance of this support in hydrotreating processes [7]. In this work, we describe the preparation and characterization of new mesoporous catalytic materials based on Ti-containing SBA-16. We study here, the effect of the preparation method of titania-modified SBA-16 (characteristics of the active Ti and/or TiO2 species) and the effect of the different operation conditions in ODS of DBT under mild conditions in order to find the best performance. TiO2-modified mesoporous SBA16 and titanium-substituted mesoporous SBA-16 were developed and tested in the oxidative desulfurization (ODS) of dibenzothiophene prevailing in liquid fuel. We assessed the impact exerted on performance of different reaction variables, including (nature and amount of the active catalytic species, phase system, molar ratio of oxidant H2O2 and DBT, reaction temperature, nature of the substrate and reuse of catalysts).