FRBA - Artículos en Revistas
Permanent URI for this collectionhttp://48.217.138.120/handle/20.500.12272/2242
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Item Adaptación de Turbina a Gas Kingtech K-100 para Hidrógeno(2023-12-31) Valvano, GuillermoEste trabajo tiene como objetivo principal adaptar una turbina a gas Kingtech K-100, diseñada originalmente para utilizar combustibles líquidos (Diésel, Queroseno, Jet A, etc.), para que pueda operar con hidrógeno de manera segura y eficiente. Para poder lograr esto, se implementaron modificaciones al sistema de inyección y lubricación de combustible. Así mismo, la turbina fue ensayada verificando que la misma puede alcanzar una aceleración de 101.400 RPM usando 100% hidrógeno. Finalmente, la turbina fue inspeccionada para verificar el estado de los componentes internos luego de su funcionamiento con hidrógeno de modo tal de verificar posibles fenómenos de corrosión que pudieran haberse generado durante la operación. La conclusión obtenida permite demostrar empíricamente que es posible adaptar este tipo de turbinas para usar hidrógeno.Item An alternative computation of the entropy of 1D signals based on geometric properties(2022-09-01) Bonini, Cristian; Rey, Andrea; Otero, Dino; Amadio, Ariel; García Blesa, Manuel; Legnani, WalterThe objective of this work is to present a novel methodology based on the computation of a couple of geometric characteristics of the position of the data points in 1D signal to propose an alternative estimation of signal entropy. The conditions to be fulfilled by the signal are minimal; only those necessary to meet the sampling theorem requirement are enough. This work shows some examples in which the proposed methodology can distinguish among signals that cannot be differentiated by other in-use alternatives. Additionally an original example where the usual ordinal pattern algorithm to compute entropy is not applicable, is presented and analyzed. The proposal developed through this work carries some advantages over other alternatives and constitutes a true advancement in the pathway to compute the distribution function of the sequential points of 1D signals later used to compute the entropy of the signal.Item Análisis de características en proyectos de big data: revisión sistemática de literatura(Revista de la Carrera de Ingeniería de Sistemas de la Facultad de Ingeniería de la Universidad de Lima, 2024-12) Ojeda, Mariel Liliana; Vegega, Cinthia; Pollo Cattaneo, María F.En el desarrollo de proyectos de big data se identifican diversas problemáticas que pueden deberse a distintos factores, como la baja calidad de los datos utilizados con anomalías que pueden afectar la precisión de los resultados o la falta de claridad en los objetivos comerciales. Esta situación puede provocar errores en el proceso de toma de decisiones, retrasos en las entregas y hasta la cancelación del proyecto. En este contexto, el presente trabajo surge de la necesidad de recopilar investigaciones previas con el fin de conocer la importancia de la aplicación de una metodología de trabajo en proyectos de big data. Se realiza con el objetivo de identificar los enfoques de las metodologías más utilizadas y analizar las características propias de cada una, así como las características comunes o transversales, que permiten la combinación, o adaptación, de distintas metodologías en un mismo proyecto. La generación de grandes volúmenes de datos provenientes de diferentes fuentes y formatos aumenta el desafío de verificar la calidad, ya que pueden presentar anomalías que afecten así la precisión de los resultados obtenidos.Item Análisis de la brecha entre la universidad y la industria del software en la República Argentina: una perspectiva docente y posibles soluciones(Fondo Editorial de la Universidad de Lima, 2024-07) Lopez Nocera, Marcelo; Pollo Cattaneo, Maria Florencia; Redelico, FranciscoSe realiza un estudio de campo para analizar la brecha existente entre la universidad y empresa. El objetivo específico es la identificación de las variables relevantes en el nivel cognitivo según la teoría institucional (como motivaciones, creencias, conceptos y percepciones) para los agentes estudiados (en este caso, docentes universitarios) y su cuantificación. En ese sentido, se delimita el universo de estudio a la Universidad Tecnológica Nacional y a las carreras relacionadas con la industria del software, para así analizar la posibilidad de reducir la brecha y mejorar la relación entre ambas.Item Analytic circuit model for thermal drying behavior of electronic inks(2023-01-23) Palumbo, FelixUnderstanding the sintering process of conductive inks is a fundamental step in the development of sensors. The intrinsic properties (such as thermal conductivity, resistivity, thermal coefficient, among others) of the printed devices do not correspond to those of the bulk materials. In the field of biosensors porosity plays a predominant role, since it defines the difference between the geometric area of the working electrode and its electrochemical surface area. The analysis reported so far in the literature on the sintering of inks are based on their DC characterization. In this work, the shape and distribution of the nanoparticles that make up the silver ink have been studied employing a transmission electron microscopy. Images of the printed traces have been obtained through a scanning electron microscope at different sintering times, allowing to observe how the material decreases its porosity over time. These structural changes were supported through electrical measurements of the change in the trace impedance as a function of drying time. The resistivity and thermal coefficient of the printed tracks were analyzed and compared with the values of bulk silver. Finally, this work proposes an analytical circuit model of the drying behavior of the ink based on AC characterization at different frequencies. The characterization considers an initial time when the spheric nanoparticles are still surrounded by the capping agent until the conductive trace is obtained. This model can estimate the characteristics that the printed devices would have, whether they are used as biosensors (porous material) or as interconnections (compact material) in printed electronicsItem Application of signal classifiers in auditory evoked potentials for the detection of pathological patients(2023-01-01) Baldiviezo, M. G.; Barbería, J.L.; Bontempo, C. B.; Corsaro, Y.; Fernández Biancardi, F.; Hernando, M. R.; Licata Caruso, L.; Paglia, A.; Rodríguez, M. R.; Legnani, W. E.The auditory brainstem response (ABR) by evoked potentials is a widespread auditory pathway assessment technique. This is largely applied due to its cost-effectiveness, practicality and ease of use. In contrast, it requires a trained professional to carry out the analysis of the results. This motivates several research efforts to increase the independence of the diagnostician. To this end, the present work shows the ability of three signal classification tools to differentiate ABR studies of normal hearing subjects from those who may have some pathology. As a starting point, the PhysioNet short term auditory evoked potentials databases are used to calculate the features later applied to construct the dataset. The features used are diverse classes of permutation entropy, fractal dimension, the Lyapunov exponent and the zero crossing rate. To ensure more accurate results, a Montecarlo simulation of one thousand trials is employed to train theItem Automated diagnosis of prostate cancer using Artificial Intelligence: a systematic literature review(2023-10-28) Soto, Salvador; Pollo Cattaneo, Ma. Florencia; Yepes Calderon, FernandoProstate cancer is one of the most preventable causes of death. Periodic testing, seconded by precursors such as living habits, heritage, and exposure, to specify materials, help healthcare providers achieve early detection, a desirable scenario that positively correlates with survival. However, the currently available diagnosing mechanisms have a great opportunity of improvement in terms of invasiveness, sensitivity and timing before patients reach advanced stages with a significant probability of metastasis. Supervised artificial intelligence enables early diagnosis and excludes patients from unpleasant biopsies. In this work, we gathered information about methodologies, techniques, metrics, and benchmarks to accomplish early prostate cancer detection, including pipelines with associated patents and knowledge transfer mechanisms intending to find the reasons precluding the solutions from being masively adopted in the standats of careItem Classification and detection of honey adulteration through corona discharge-induced plasma spectroscopy and electronic plasma nose(2021-06-30) Ferrarra, Leonardo; Puntoriero, Luis; Boggio, Norberto; Vorobioff, Juan; Cáceres, Jorge; De Simone, Ricardo; Rinaldi, CarlosIn the past, a large group of syrups and markers of honey adulteration have been identified, but new syrups are now closely matching their composition, and detection of honey adulteration is becoming considerably more difficult. In this work, we present a methodology that allows us to characterize honey samples providing a solution to this problem using corona discharge-induced plasma spectroscopy (CDIPS) in conjunction with electronic plasma nose (eP-Nose). Applying chemometric analysis it was possible to distinguish the different types of honey and determine the degree of adulteration in them with corn syrup. To our knowledge, this is the first time that this technique has been applied to determine the fingerprint (authenticity) of honey samples of different origins. The elemental composition of honey provides enough information to get correct discrimination of different adulteration. The result of the chemometric analysis showed over 98% certainty and all honey samples were correctly identified. There have been no instances of false positives or false negatives in our tests or applications. This methodology shows high potential as an alternative method for monitoring and analyzing the quality and purity in honey production, especially for fraud detection.Item De la urgencia pandémica a nuevas alternativas de enseñanza(2022-10-07) Paruelo, JorgeEl período de pandemia obligó a los profesores a adoptar nuevas formas para llevar adelante las cursadas de las materias dentro de la universidad. Hubo que utilizar recursos tecnológicos para la enseñanza remota pensando en abarcar los casos de estudiantes con baja disponibilidad técnica y también buscando sostener la calidad de la enseñanza. Esto condujo a un entrenamiento de los profesores en nuevas tecnologías y nuevas estrategias de enseñanza. Este artículo toma la experiencia adquirida y la combina con un recurso didáctico recuperado de un curso de ingreso universitario de hace más de medio siglo junto con la metodología conocida como “aula invertida” para diseñar un tipo de curso que apunta a la participación activa del estudiante en su aprendizaje en el aula.Item Decoupling the sequence of dielectric breakdown in single device bilayer stacks by radiation-controlled, spatially localized creation of oxide defects(2021-06-14) Palumbo, FelixThe breakdown (BD) sequence in high-K/interfacial layer (HK/IL) stacks for timedependent dielectric breakdown (TDDB) has remained controversial for sub-45 nm CMOS nodes, as many attempts to decode it were not based on proper experimental methods. Knowhow of this sequence is critical to the future design for reliability of FinFETs and nanosheet transistors. We present here the use of radiation fluence as a tool to precisely tune the defect density in the dielectric layer, which jointly with the statistical study of the soft, progressive and hard BD, allow us to infer the BD sequence using a single HfO2-SiOx bilayered MOS structureItem El desarrollo sostenible (DS) en la formación de ingenieros: un nuevo campo para repensar la perspectiva CTS(2017-05-01) Ramallo, Milena; Cardaci, Karina Florencia; Costucica, Leonardo Adán DouglasEste trabajo parte del supuesto que la incorporación de la enseñanza de la ingeniería en el ámbito universitario es una novedad del siglo XX y está vinculada al modelo productivo del segundo ciclo de acumulación del capital. Ese modo de producción industrial se nutre de aquella cosmovisión, aún dominante aunque haya entrado en crisis. En este contexto, el Desarrollo Sostenible (DS) se propone como uno de los aspectos del campo actual de la Ciencia, Tecnología y Sociedad (CTS). El objetivo de este trabajo es reflexionar acerca de los posibles cambios que esta nueva visión aporte a la formación de los ingenieros. Para ello, se propone el análisis de los cambios en la concepción de la ingeniería y en especial qué genera el nuevo paradigma, a nivel nacional, regional e internacional. Por último, se concluye sobre el desafío de la ingeniería para contribuir con el DS.Item Detection of cardiac arrhythmia patterns in ECG through H × C plane(2022-12-05) Martínez Coq, P.; Rey, A.; Rosso, O. A.; Armentano, R.; Legnani, W.The aim of this study is to formulate a new methodology based upon informational tools to detect patients with cardiac arrhythmias. As it is known, sudden death is the consequence of a final arrhythmia, and here lies the relevance of the efforts aimed at the early detection of arrhythmias. The information content in the time series from an electrocardiogram (ECG) signal is conveyed in the form of a probability distribution function, to compute the permutation entropy proposed by Bandt and Pompe. This selection was made seeking its remarkable conceptual simplicity, computational speed, and robustness to noise. In this work, two well-known databases were used, one containing normal sinus rhythms and another one containing arrhythmias, both from the MIT medical databank. For different values of embedding time delay τ normalized permutation entropy and statistical complexity measure are computed to finally represent them on the horizontal and vertical axes, respectively, which define the causal plane H × C. To improve the results obtained in previous works, a feature set composed by these two magnitudes is built to train the following supervised machine learning algorithms: random forest (RF), support vector machine (SVM), and k nearest neighbors (kNN). To evaluate the performance of each classification technique, a 10-fold cross-validation scheme repeated 10 times was implemented. Finally, to select the best model, three quality parameters were computed, namely, accuracy, the area nder the receiver operative characteristic (ROC) curve (AUC), and the F1-score. The results obtained show that the best classification model to detect the ECG coming from arrhythmic patients is RF. The values of the quality parameters were at the same levels reported in the available literature using a larger data set, thus supporting this proposal that uses a very small-sized feature space to train the model later used to classify. Summarizing, the attained results show the possibility to discriminate both groups of patients, with normal sinus rhythm or arrhythmic ECG, showing a promising efficiency in the definition of new markers for the detection of cardiovascular pathologies.Item Discussing discarded models: an integrative teaching resource(2024-10-01) Paruelo, JorgeThis study proposes a kind of teaching resource adaptable to different levels of teaching and training objectives that allows the introduction of contextual issues and concepts of history and the nature of science while providing tools for learning modeling and integrating different kinds of knowledge. A controversial case from science history was sought to develop an integrating teaching activity. The case to find must be one that confront at least two different models to solve a scientific problem or a technological one. Torricelli’s theory vs. horror vacui theory as it was modified by Galileo result a useful case to take as content for the teaching activity. Groups of students must argument in favor and against each of theories or models. The proposed activity introduces future teachers in the student’s role, considering that they will play the teacher’s role when they use similar activities with their future students. Moreover, it trains future physics teachers to integrate modeling, history and nature of science.Item ECG signals classification using overlapping variables to detect atrial fibrillation(2022-03-01) Ziccardi, I. G.; Rey, A. A.; Legnani, W. E.In the present work a method for the detection of the cardiac pathology known as atrial fibrillation is proposed by calculating different information, statistics and other nonlinear measures over ECG signals. The original database contains records corresponding to patients who are diagnosed with this disease as well as healthy subjects. To formulate the dataset the R´enyi permutation entropy, Fisher information measure, statistical complexity, Lyapunov exponent and fractal dimension were calculated, in order to determine how to combine this features to optimize the identification of the signals coming from ECG with the above mentioned cardiac pathology. With the aim to improve the results obtained in previous studies, a classification method based upon decision trees algorithms is implemented. Later a Montecarlo simulation of one thousand trials is performed with a seventy percent randomly selected from the dataset dedicated to train the classifier and the remaining thirty percent reserved to test in every trial. The quality of the classification is assessed through the computation of the area under the receiver operation characteristic curve (ROC), the F1-score and other classical performance metrics, such as the balanced accuracy, sensitivity, specificity, positive and negative predicted values. The results show that the incorporation of all these features to the dataset when are employed to train the classifier in the training task produces the best classification, in such a way that the largest quality parameter is achieved.Item Effect of different gases on the sonochemical Cr(VI) reduction in the presence of citric acid(2020-12-01) Meichtry, Jorge Martín; Cancelada, Lucía; Destaillats, Hugo; Litter, Marta IreneThe sonochemical (850 kHz) Cr(VI) reduction (0.30 mM, pH 2) in the presence of citric acid (Cit, 2 mM) was analyzed under different working atmospheres: reactor open to air without sparging (ROAWS), and Ar, O2, air and N2 sparging. Hydrogen peroxide formation in pure water at pH 2 and KI dosimetry were also measured. Zero-order kinetics was observed in all cases. A complete Cr(VI) reduction after 180 min insonation was obtained with the ROAWS and under Ar, while a lower Cr(VI) reduction efficiency was achieved under the other conditions. The Cr(VI) reduction and H2O2 formation rates followed the order ROAWS ?° Ar > air ?° O2 >> N2, while for KI dosimetry the order was ROAWS >> O2 ?° air > Ar >> N2. This indicates that H2O2 formation rate is a better measure of the system reactivity for Cr(VI) reduction. For air, O2 and N2, once the sparging was stopped, Cr(VI) reduction rate increased up to approximately the same value obtained for the ROAWS, suggesting that the sparging decreased the generation of reactive species and, thus, the Cr(VI) reduction rate. Nitrate production was measured at low concentrations (micromolar range) in the ROAWS, air and N2 systems. Formic and acetic acids were detected as Cit degradation products. Reaction mechanisms were proposed. It can be concluded that the best conditions for Cr(VI) removal are with the ROAWS because of a higher Cr(VI) reduction rate, no atmosphere control is required, and it is a less expensive system.Item Ejes de Innovación en el Sector Textil a Nivel Global(2022-12) Marino, PatriciaEl sector textil está inmerso en grandes transformaciones en tal sentido podemos mencionar dos ejes a partir de los cuales surgen múltiples desarrollos. Ellos son: la digitalización y la sostenibilidad destacando que en ambos casos el rol de la investigación y la innovación, representan actividades centrales potenciadas en la actualidad por la pandemia.Item La evaluación de la Responsabilidad Social Universitaria(2015-07-02) Ramallo, MilenaEn la construcción del concepto de Responsabilidad Social Universitaria (RSU) y su evaluación en especial en el nivel universitario, podemos encontrar distintas formas de comprenderlo dado el múltiple marco referencial existente sobre el tema. Sin embargo, estas nociones aún han sido poco estudiadas y desarrolladas por grupos de investigadores en universidades o centros de estudio, y menos aún resignificadas distinguiéndolas del sentido que poseen en el ámbito empresarial. Varios estudios plantean la necesidad de proponer criterios que permitan determinar si una facultad o universidad actúa con responsabilidad social: el tema de su evaluación. El análisis realizado en el presente trabajo muestra la relación existente entre las concepciones de RSU y las concepciones de su evaluación.Item Evaluation of the bias in the management of patient’s appointments in a pediatric office(2020-04-01) Vegega, Cinthia; Pytel, Pablo; Pollo Cattaneo, María FlorenciaThe application of Machine Learning algorithms must always take into account the objectives set within the project, the characteristics of the domain where the project will be carried out and the data available to use. Given this, it is essential before collecting data considered as representative of the problem to be solved, because otherwise there may be hidden biases in the data and these may solve a different problem from the one intended. In this context, the aim of this work is to apply a process based on the Gridding method that allows the analysis of the features of the data to be used. This process is applied to the historical data of a pediatric medical office where it is sought to implement an intelligent system that allows to predict the number of normal and overshift appointments for a particular date and time, since it is desired to hire, when necessary, another pediatric doctor to assist in the care of patients.Item Imágenes de mujeres en la cultura ferroviaria. La revista del F.C.C.A. como caso de estudio (Argentina 1911-1915).(2023-04-14) Bonelli Zapata, Ana LauraEl objetivo de este trabajo es analizar la Revista del Ferrocarril Central Argentino, entre 1911 y 1915, desde el foco de los estudios visuales y la historia social de las mujeres. Las representaciones de mujeres aparecidas en la revista entre su primer número y el inicio de la Gran Guerra permiten revelar tensiones entre la supuesta transparencia de las imágenes y la materialidad del impreso, su producción, manipulación y circulación, definiéndolo como un dispositivo cultural, atravesado por los discursos en torno a las diferencias y los roles asociados a los géneros. Consideramos que el ferrocarril y la revista ilustrada funcionaron como instituciones sociales mediante las cuales circularon los símbolos culturales (y los conceptos normativos asociados a ellos). Se intentará, a partir del análisis de las ilustraciones y fotografías de mujeres, comprender de qué manera la imagen impresa reforzó o tensionó esos significados, construyendo una representación de lo femenino dentro de un contexto marcado por la masculinidad.Item Ingeniería y Sociedad: aportes de los estudios CTS en la formación de los ingenieros(2019-06-28) Ramallo, Milena; Repetto, Élida; Gayoso, María Celia; Giacomino, RosaEl objetivo de este trabajo es presentar los aportes del enfoque CTS e incorporarlos a la asignatura "Ingeniería y sociedad" en las carreras de ingeniería de la Universidad Tecnológica Nacional de Argentina. Esta fundamentación brinda elementos teóricos y metodológicos para la reflexión sobre la pertinencia de este campo de estudio-trabajo en la formación de ingenieros. Su objeto de estudio se centra en la relación entre la ciencia y la tecnología, hoy en día atravesada por una nueva concepción de la ingeniería atenta a las necesidades de una sociedad que anhela alcanzar el desarrollo sustentable. Esto ha impuesto un nuevo desafío a la ciencia y la tecnología, y este nuevo modelo a su vez se relaciona profundamente con la nueva manera de comprender la relación ciencia-tecnología-ingeniería-industria en un mundo complejo y cambiante. Por ello nos proponemos desarrollar en los estudiantes la capacidad de comprensión de ese mundo que les toca vivir y de los desafíos que tendrá que afrontar el ingeniero, así como también entender el valor social de la ingeniería.