Luis Octavio González-Salcedo, Francisco Adolfo Marmolejo-Villanueva, Diego Alexander Quiroz-Morán, Karen Andrea Ospina-Trujillo, Ricardo Malagón Manrique
One branch of civil engineering is construction engineering, geared primarily towards humans. However, this branch also includes buildings designed for animals called animal housing (dwellings or shelters or corrals). Like physical spaces for humans, animal housing requires sufficient conditions for an occupation that guarantees the performance of indoor activities pleasantly and comfortably. One of the parameters for characterizing and classifying the penned livestock farm environment is the thermal comfort range that reflects the indoor temperature behavior for animal welfare, together with other climatic elements such as relative humidity. This research carried out fieldwork to evaluate the thermal environment of pigpens located in Palmira, Colombia, in the time range between 07:00 and 21:00 hours. Using thermometers and hygrometers, we recorded and analyzed the indoor temperature behavior within the thermal comfort range associated with relative humidity for the well-being of pigs. The records made it possible to calculate humidity and temperature index and humidity and black globe temperature index. According to the results, the pig rearing environment was classified as critical for breeding pigs and newborn piglets, suggesting the use of controlled environment systems in pig facilities. In conclusion, monitoring the climatic environment by criteria that combine air temperature and relative humidity is a useful tool for planning pig facilities.
{"title":"Monitoring and Characterization of the Thermal Environment of Special-Use Buildings","authors":"Luis Octavio González-Salcedo, Francisco Adolfo Marmolejo-Villanueva, Diego Alexander Quiroz-Morán, Karen Andrea Ospina-Trujillo, Ricardo Malagón Manrique","doi":"10.18359/rcin.4435","DOIUrl":"https://doi.org/10.18359/rcin.4435","url":null,"abstract":"One branch of civil engineering is construction engineering, geared primarily towards humans. However, this branch also includes buildings designed for animals called animal housing (dwellings or shelters or corrals). Like physical spaces for humans, animal housing requires sufficient conditions for an occupation that guarantees the performance of indoor activities pleasantly and comfortably. One of the parameters for characterizing and classifying the penned livestock farm environment is the thermal comfort range that reflects the indoor temperature behavior for animal welfare, together with other climatic elements such as relative humidity. This research carried out fieldwork to evaluate the thermal environment of pigpens located in Palmira, Colombia, in the time range between 07:00 and 21:00 hours. Using thermometers and hygrometers, we recorded and analyzed the indoor temperature behavior within the thermal comfort range associated with relative humidity for the well-being of pigs. The records made it possible to calculate humidity and temperature index and humidity and black globe temperature index. According to the results, the pig rearing environment was classified as critical for breeding pigs and newborn piglets, suggesting the use of controlled environment systems in pig facilities. In conclusion, monitoring the climatic environment by criteria that combine air temperature and relative humidity is a useful tool for planning pig facilities.","PeriodicalId":31201,"journal":{"name":"Ciencia e Ingenieria Neogranadina","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-12-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49273879","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Jeyson A. Castillo, Yenny C. Granados, Carlos Augusto Fajardo Ariza
Atrial Fibrillation (AF) is the most common cardiac arrhythmia worldwide. It is associated with reduced quality of life and increases the risk of stroke and myocardial infarction. Unfortunately, many cases of AF are asymptomatic and undiagnosed, which increases the risk for the patients. Due to its paroxysmal nature, the detection of AF requires the evaluation, by a cardiologist, of long-term ECG signals. In Colombia, it is difficult to have access to an early diagnosis of AF because of the associated costs to the detection and the geographical distribution of cardiologists. This work is part of a macro project that aims to develop a specific-patient portable device for the detection of AF. This device will be based on a Convolutional Neural Network (CNN). We aim to find a suitable CNN model, which later could be implemented in hardware. Diverse techniques were applied to improve the answer regarding accuracy, sensitivity, specificity, and precision. The final model achieves an accuracy of , a specificity of , a sensitivity of and a precision of . During the development of the model, the computational cost and memory resources were taking into account in order to obtain an efficient hardware model in a future implementation of the device.
{"title":"Patient-Specific Detection of Atrial Fibrillation in Segments of ECG Signals using Deep Neural Networks","authors":"Jeyson A. Castillo, Yenny C. Granados, Carlos Augusto Fajardo Ariza","doi":"10.18359/rcin.4156","DOIUrl":"https://doi.org/10.18359/rcin.4156","url":null,"abstract":"Atrial Fibrillation (AF) is the most common cardiac arrhythmia worldwide. It is associated with reduced quality of life and increases the risk of stroke and myocardial infarction. Unfortunately, many cases of AF are asymptomatic and undiagnosed, which increases the risk for the patients. Due to its paroxysmal nature, the detection of AF requires the evaluation, by a cardiologist, of long-term ECG signals. In Colombia, it is difficult to have access to an early diagnosis of AF because of the associated costs to the detection and the geographical distribution of cardiologists. This work is part of a macro project that aims to develop a specific-patient portable device for the detection of AF. This device will be based on a Convolutional Neural Network (CNN). We aim to find a suitable CNN model, which later could be implemented in hardware. Diverse techniques were applied to improve the answer regarding accuracy, sensitivity, specificity, and precision. The final model achieves an accuracy of , a specificity of , a sensitivity of and a precision of . During the development of the model, the computational cost and memory resources were taking into account in order to obtain an efficient hardware model in a future implementation of the device.","PeriodicalId":31201,"journal":{"name":"Ciencia e Ingenieria Neogranadina","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41364725","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
J. A. Florez Zuluaga, Esteban Patiño Carrasco, Jose David Ortega Pabon, Kelly Gallego Leon, O. L. Quintero Montoya
The decision-making (DM) process in critical environments is a complex process that can be simulated due to current telematic capabilities, which allow the real time interaction of large amounts of data. This document describes the proposed architecture from a research process, developed by the FAC Aerospace Technology Development Center (CETAD), where using computational and expert system tools, allowed to create a computational environment for decision maker evaluated his options to prepares for real events, simulating characteristics, resources and strategies in a real time environment. This document describes an investigation product resulted in a simulation system, based on a combination of fuzzy logic, genetic algorithms and decision trees which let modelled and simulated various entities and their automatic response according to simulated patterns and situations, in which, through operators, decision maker can modify entities behaviour, according to parameterized restrictions and physical conditions. Also based on business intelligence tools, reports are generated to evaluate the decisions made. This type of technologies improves planning capacity and facilitate the decision-making process. System allows simulating any media deployment in national security and critical events context. Thus, a case study was developed for implementation of a support in natural disaster scenario simulation
{"title":"A Data Fusion System for Simulation of Critical Scenarios and Decision-Making","authors":"J. A. Florez Zuluaga, Esteban Patiño Carrasco, Jose David Ortega Pabon, Kelly Gallego Leon, O. L. Quintero Montoya","doi":"10.18359/rcin.4131","DOIUrl":"https://doi.org/10.18359/rcin.4131","url":null,"abstract":"The decision-making (DM) process in critical environments is a complex process that can be simulated due to current telematic capabilities, which allow the real time interaction of large amounts of data. This document describes the proposed architecture from a research process, developed by the FAC Aerospace Technology Development Center (CETAD), where using computational and expert system tools, allowed to create a computational environment for decision maker evaluated his options to prepares for real events, simulating characteristics, resources and strategies in a real time environment. \u0000This document describes an investigation product resulted in a simulation system, based on a combination of fuzzy logic, genetic algorithms and decision trees which let modelled and simulated various entities and their automatic response according to simulated patterns and situations, in which, through operators, decision maker can modify entities behaviour, according to parameterized restrictions and physical conditions. Also based on business intelligence tools, reports are generated to evaluate the decisions made. This type of technologies improves planning capacity and facilitate the decision-making process. \u0000System allows simulating any media deployment in national security and critical events context. Thus, a case study was developed for implementation of a support in natural disaster scenario simulation","PeriodicalId":31201,"journal":{"name":"Ciencia e Ingenieria Neogranadina","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46244073","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Nowadays, mobile robots begin to appear in public places. To do these tasks properly, mobile robots must interact with humans. This paper presents the development of GUI3DXBot, a software tool for a tour-guide mobile robot. The paper focuses on the development of different software modules needed to guide users in an office building. In this context, GUI3DXBot is a server-client application, where the server side runs into the robot, and the client side runs into a 10-inch Android tablet. The GUI3DXBot server side is in charge of performing the perception, localization-mapping, and path planning tasks. The GUI3DXBot client side implements the human-robot interface that allows users requesting-canceling a tour-guide service, showing robot localization in the map, interacting with users, and tele-operating the robot in case of emergency. The contributions of this paper are twofold: it proposes a software modules design to guide users in an office building, and the whole robot system was well integrated and fully tested. GUI3DXBot were tested using software integration and field tests. The field tests were performed over a two-week period, and a survey to users was conducted. The survey results show that users think GUI3DXBot is friendly and intuitive, the goal selection was very easy, the interactive messages were very easy to understand, 90% of users found useful the robot icon on the map, users found useful drawing the path on the map, 90% of users found useful the local-global map view, and the guidance experience was very satisfactory (70%) and satisfactory (30%).
{"title":"GUI3DXBot: An Interactive Software Tool for a Tour-Guide Mobile Robot","authors":"Kevin Muñoz Peña, Bladimir Bacca Cortés","doi":"10.18359/rcin.3644","DOIUrl":"https://doi.org/10.18359/rcin.3644","url":null,"abstract":"Nowadays, mobile robots begin to appear in public places. To do these tasks properly, mobile robots must interact with humans. This paper presents the development of GUI3DXBot, a software tool for a tour-guide mobile robot. The paper focuses on the development of different software modules needed to guide users in an office building. In this context, GUI3DXBot is a server-client application, where the server side runs into the robot, and the client side runs into a 10-inch Android tablet. The GUI3DXBot server side is in charge of performing the perception, localization-mapping, and path planning tasks. The GUI3DXBot client side implements the human-robot interface that allows users requesting-canceling a tour-guide service, showing robot localization in the map, interacting with users, and tele-operating the robot in case of emergency. The contributions of this paper are twofold: it proposes a software modules design to guide users in an office building, and the whole robot system was well integrated and fully tested. GUI3DXBot were tested using software integration and field tests. The field tests were performed over a two-week period, and a survey to users was conducted. The survey results show that users think GUI3DXBot is friendly and intuitive, the goal selection was very easy, the interactive messages were very easy to understand, 90% of users found useful the robot icon on the map, users found useful drawing the path on the map, 90% of users found useful the local-global map view, and the guidance experience was very satisfactory (70%) and satisfactory (30%).","PeriodicalId":31201,"journal":{"name":"Ciencia e Ingenieria Neogranadina","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47698418","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Daniel Orlando Martínez Quezada, Robinson Ortiz Sierra, Juan Guillermo Martínez Cano, Henry Lamos Díaz
Twitter se ha convertido en una herramienta importante para conocer en tiempo real lo que sucede en el mundo político, social y económico. Esta plataforma es cada vez más atractiva como medio de comunicación para diferentes tipos de eventos, puede ser usada en procesos de operaciones logísticas y humanitarias mejorando la comunicación entre los actores involucrados en una situación de un desastre natural. El enfoque de Análisis de Redes Sociales ARS se usó para datos generados en la red social Twitter para un evento de desastre natural, analizando tres actores importantes, los usuarios, hashtags y URLs. En el presente trabajo se presenta una metodología ARS implementada en un caso de estudio de desastre (erupción del volcán Sinabung en 2018). A partir de los análisis se identificaron usuarios, temas y fuentes de información relevantes durante la ocurrencia del desastre. Los análisis ofrecen una vista general de las interacciones e impacto de los elementos más influyentes durante el evento bajo estudio, teniendo una importancia destacada los equipos de noticia, redes sociales y centros de investigación. Los hallazgos del estudio son comparados con un estudio anterior, encontrando similitudes en la mayoría de estos, sin embargo, en nuestro estudio se identificó nuevos actores del ámbito técnico académico que buscan contribuir y difundir información relevante del evento disruptivo.
{"title":"Identificación de actores en un desastre a través de Twitter: Caso de estudio SINABUNG 2018","authors":"Daniel Orlando Martínez Quezada, Robinson Ortiz Sierra, Juan Guillermo Martínez Cano, Henry Lamos Díaz","doi":"10.18359/rcin.3938","DOIUrl":"https://doi.org/10.18359/rcin.3938","url":null,"abstract":"Twitter se ha convertido en una herramienta importante para conocer en tiempo real lo que sucede en el mundo político, social y económico. Esta plataforma es cada vez más atractiva como medio de comunicación para diferentes tipos de eventos, puede ser usada en procesos de operaciones logísticas y humanitarias mejorando la comunicación entre los actores involucrados en una situación de un desastre natural. El enfoque de Análisis de Redes Sociales ARS se usó para datos generados en la red social Twitter para un evento de desastre natural, analizando tres actores importantes, los usuarios, hashtags y URLs. En el presente trabajo se presenta una metodología ARS implementada en un caso de estudio de desastre (erupción del volcán Sinabung en 2018). A partir de los análisis se identificaron usuarios, temas y fuentes de información relevantes durante la ocurrencia del desastre. Los análisis ofrecen una vista general de las interacciones e impacto de los elementos más influyentes durante el evento bajo estudio, teniendo una importancia destacada los equipos de noticia, redes sociales y centros de investigación. Los hallazgos del estudio son comparados con un estudio anterior, encontrando similitudes en la mayoría de estos, sin embargo, en nuestro estudio se identificó nuevos actores del ámbito técnico académico que buscan contribuir y difundir información relevante del evento disruptivo.","PeriodicalId":31201,"journal":{"name":"Ciencia e Ingenieria Neogranadina","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47441269","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Oscar Julián Perdomo Charry, Fabio Augusto González Osorio
Artificial intelligence is having an important effect on different areas of medicine, and ophthalmology has not been the exception. In particular, deep learning methods have been applied successfully to the detection of clinical signs and the classification of ocular diseases. This represents a great potential to increase the number of people correctly diagnosed. In ophthalmology, deep learning methods have primarily been applied to eye fundus images and optical coherence tomography. On the one hand, these methods have achieved an outstanding performance in the detection of ocular diseases such as: diabetic retinopathy, glaucoma, diabetic macular degeneration and age-related macular degeneration. On the other hand, several worldwide challenges have shared big eye imaging datasets with segmentation of part of the eyes, clinical signs and the ocular diagnostic performed by experts. In addition, these methods are breaking the stigma of black-box models, with the delivering of interpretable clinically information. This review provides an overview of the state-of-the-art deep learning methods used in ophthalmic images, databases and potential challenges for ocular diagnosis
{"title":"A Systematic Review of Deep Learning Methods Applied to Ocular Images","authors":"Oscar Julián Perdomo Charry, Fabio Augusto González Osorio","doi":"10.18359/rcin.4242","DOIUrl":"https://doi.org/10.18359/rcin.4242","url":null,"abstract":"Artificial intelligence is having an important effect on different areas of medicine, and ophthalmology has not been the exception. In particular, deep learning methods have been applied successfully to the detection of clinical signs and the classification of ocular diseases. This represents a great potential to increase the number of people correctly diagnosed. In ophthalmology, deep learning methods have primarily been applied to eye fundus images and optical coherence tomography. On the one hand, these methods have achieved an outstanding performance in the detection of ocular diseases such as: diabetic retinopathy, glaucoma, diabetic macular degeneration and age-related macular degeneration. On the other hand, several worldwide challenges have shared big eye imaging datasets with segmentation of part of the eyes, clinical signs and the ocular diagnostic performed by experts. In addition, these methods are breaking the stigma of black-box models, with the delivering of interpretable clinically information. This review provides an overview of the state-of-the-art deep learning methods used in ophthalmic images, databases and potential challenges for ocular diagnosis","PeriodicalId":31201,"journal":{"name":"Ciencia e Ingenieria Neogranadina","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42555725","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
La estimación de la distribución de calor en superfcie y a profundidades someras (20 cm,100 cm y 150 cm) por medio de los sondeos superfciales de temperatura (SST) para el área geotérmica del volcán Azufral encontró anomalías entre los 6ºC y los 20ºC. A su vez, se realizaron modelosde temperatura mediante imágenes Landsat 8 del sensor TIRS (por sus siglas en inglés), que permitieron alcanzar una aproximación de la distribución de calor en superfcie con tres imágenes confecha de toma cercanas a las fechas de levantamiento de los SST. Integrando el índice de vegetaciónde diferencia normalizada (NDVI, por sus siglas en inglés) (entre 0,93 y -0,563) y la topografía (alturasentre 2800 msnm y 3800 msnm) en secciones cruzadas mediante técnicas de análisis espacial, seanalizaron las anomalías positivas y negativas de estas tres variables en el área geotérmica. Con laestimación del coefciente de Pearson como método cuantitativo para el análisis de las correlacionesentre los diferentes modelos generados, se denota que existe una fuerte correlación positiva (entre0,19 y 0,46) entre las temperaturas en profundidad contra las temperaturas para cada uno de los díascalculados con Landsat 8 TIRS.
{"title":"Modelos de temperatura del suelo a partir de sondeos superfciales de temperatura y sensores remotos para el área geotérmica del volcán Azufral","authors":"Jhon Camilo Matiz León, Gilbert Fabian Rodríguez Rodríguez, Claudia María Alfaro Valero","doi":"10.18359/rcin.3400","DOIUrl":"https://doi.org/10.18359/rcin.3400","url":null,"abstract":"La estimación de la distribución de calor en superfcie y a profundidades someras (20 cm,100 cm y 150 cm) por medio de los sondeos superfciales de temperatura (SST) para el área geotérmica del volcán Azufral encontró anomalías entre los 6ºC y los 20ºC. A su vez, se realizaron modelosde temperatura mediante imágenes Landsat 8 del sensor TIRS (por sus siglas en inglés), que permitieron alcanzar una aproximación de la distribución de calor en superfcie con tres imágenes confecha de toma cercanas a las fechas de levantamiento de los SST. Integrando el índice de vegetaciónde diferencia normalizada (NDVI, por sus siglas en inglés) (entre 0,93 y -0,563) y la topografía (alturasentre 2800 msnm y 3800 msnm) en secciones cruzadas mediante técnicas de análisis espacial, seanalizaron las anomalías positivas y negativas de estas tres variables en el área geotérmica. Con laestimación del coefciente de Pearson como método cuantitativo para el análisis de las correlacionesentre los diferentes modelos generados, se denota que existe una fuerte correlación positiva (entre0,19 y 0,46) entre las temperaturas en profundidad contra las temperaturas para cada uno de los díascalculados con Landsat 8 TIRS.","PeriodicalId":31201,"journal":{"name":"Ciencia e Ingenieria Neogranadina","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-08-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45537101","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
W. Campo, Andrés Felipe Escobar Zapata, Juan Carlos Imbachi Paz
El video streaming es el servicio que mayor porcentaje de tráfco genera con respecto altotal de datos en las redes móviles de evolución de largo plazo LTE (por sus siglas en inglés). Por otraparte, el protocolo de Streaming Adaptativo Dinámico sobre HTPP (DASH, por sus siglas en inglés)ha sido seleccionado para la transmisión del video en las redes LTE. Así, en este artículo, se presentael análisis del comportamiento del servicio de video mediante una implementación de DASH bajológica difusa denominada FDASH (fuzzy DASH) en una red LTE, considerando diferente número deusuarios y traspasos (handover). Se analizan parámetros de calidad de servicio, como retardo, pérdida de paquetes, variación de pérdida de paquetes y rendimiento. Mediante este trabajo, se presentaFDASH como opción para el consumo del servicio de video, ya que permite adaptarse a las diferentescondiciones y exigencias de la tecnología inalámbrica móvil LTE.
{"title":"Análisis del servicio de video streaming basado en el algoritmo FDASH sobre LTE","authors":"W. Campo, Andrés Felipe Escobar Zapata, Juan Carlos Imbachi Paz","doi":"10.18359/rcin.3122","DOIUrl":"https://doi.org/10.18359/rcin.3122","url":null,"abstract":"El video streaming es el servicio que mayor porcentaje de tráfco genera con respecto altotal de datos en las redes móviles de evolución de largo plazo LTE (por sus siglas en inglés). Por otraparte, el protocolo de Streaming Adaptativo Dinámico sobre HTPP (DASH, por sus siglas en inglés)ha sido seleccionado para la transmisión del video en las redes LTE. Así, en este artículo, se presentael análisis del comportamiento del servicio de video mediante una implementación de DASH bajológica difusa denominada FDASH (fuzzy DASH) en una red LTE, considerando diferente número deusuarios y traspasos (handover). Se analizan parámetros de calidad de servicio, como retardo, pérdida de paquetes, variación de pérdida de paquetes y rendimiento. Mediante este trabajo, se presentaFDASH como opción para el consumo del servicio de video, ya que permite adaptarse a las diferentescondiciones y exigencias de la tecnología inalámbrica móvil LTE.","PeriodicalId":31201,"journal":{"name":"Ciencia e Ingenieria Neogranadina","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-08-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44558737","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Eimar Sandoval-Vallejo, William Albeiro Rivera-Mena
Los espesores y propiedades de las capas de una estructura de pavimento son altamentedeterminados por la rigidez de la subrasante. En algunos casos, no es posible la ejecución de pruebas directas para determinar dicha rigidez, al menos en la frecuencia requerida, y es necesario usarcorrelaciones con otras propiedades del suelo. Este artículo presenta resultados de un programaexperimental realizado para obtener correlaciones entre el CBR (por sus siglas en inglés) inalteradode suelos fnos con su resistencia a la compresión inconfnada o algunas propiedades índice. Se realizaron ensayos de CBR de laboratorio, resistencia a la compresión inconfnada, límites de Atterberg,granulometría y humedad natural. El número de muestras (38) fue seleccionado para garantizar seguridad y poder estadístico del 95 % y un coefciente de correlación de Pearson (r) mínimo de 0,60.Aunque no fue posible correlacionar el CBR con las propiedades índice evaluadas, se obtuvieroncorrelaciones entre el CBR natural y saturado, y la resistencia a la compresión inconfnada. Las correlaciones obtenidas, que tuvieron valores r > 0,80, fueron comparadas con algunas correlaciones en laliteratura entre el CBR y otros ensayos de resistencia no drenada. Para la misma resistencia, los CBRen este estudio son considerablemente menores que los de dichas correlaciones.
{"title":"Correlación del CBR con la resistencia a la compresión inconfnada","authors":"Eimar Sandoval-Vallejo, William Albeiro Rivera-Mena","doi":"10.18359/rcin.3478","DOIUrl":"https://doi.org/10.18359/rcin.3478","url":null,"abstract":"Los espesores y propiedades de las capas de una estructura de pavimento son altamentedeterminados por la rigidez de la subrasante. En algunos casos, no es posible la ejecución de pruebas directas para determinar dicha rigidez, al menos en la frecuencia requerida, y es necesario usarcorrelaciones con otras propiedades del suelo. Este artículo presenta resultados de un programaexperimental realizado para obtener correlaciones entre el CBR (por sus siglas en inglés) inalteradode suelos fnos con su resistencia a la compresión inconfnada o algunas propiedades índice. Se realizaron ensayos de CBR de laboratorio, resistencia a la compresión inconfnada, límites de Atterberg,granulometría y humedad natural. El número de muestras (38) fue seleccionado para garantizar seguridad y poder estadístico del 95 % y un coefciente de correlación de Pearson (r) mínimo de 0,60.Aunque no fue posible correlacionar el CBR con las propiedades índice evaluadas, se obtuvieroncorrelaciones entre el CBR natural y saturado, y la resistencia a la compresión inconfnada. Las correlaciones obtenidas, que tuvieron valores r > 0,80, fueron comparadas con algunas correlaciones en laliteratura entre el CBR y otros ensayos de resistencia no drenada. Para la misma resistencia, los CBRen este estudio son considerablemente menores que los de dichas correlaciones.","PeriodicalId":31201,"journal":{"name":"Ciencia e Ingenieria Neogranadina","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-08-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46303656","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Cateryna Aiello Mazzarri, Yenmilet Salazar, Aidin Urribarrí, Elsy Arenas Dávila, John Sánchez Fuentes, F. Ysambertt
La búsqueda de materias primas no alimenticias es uno de los principales retos en la producción de biocombustibles. Para biodiésel, las investigaciones se orientan hacia el uso de cultivosno convencionales, así como hacia residuos o desechos con alto contenido de grasas y aceites. Laborra de café contiene una buena proporción de grasas y es un residuo comercial y doméstico. Eneste trabajo, se evaluó la producción de biodiésel utilizando las grasas extraídas de la borra del cafémediante un proceso en dos etapas. Las grasas extraídas de la borra de café con ebullición a reflujocon hexano como solvente presentaron una elevada acidez, 32,07 ± 0,01% (70,24 ± 0,03 mg KOH/ggrasa), lo que indica un alto contenido de ácidos grasos libres (AGL). Primero, las grasas se esterifcaron a 60ºC y 100 rpm, variando las condiciones de reacción. A las mejores condiciones, concentraciónde H2SO4 al 0,7%, RMG:MeOH de 1:6 durante 120 min, la acidez disminuyó por debajo del 1%, conel 94,92% de conversión AGL a ésteres metílicos. Se sometieron a un proceso de transesterifcacióncon KOH (1,5% m/v) en presencia de metanol (RMG:MeOH de 1:15) a 60ºC y 100 rpm durante 30 min.El biodiésel se separó por decantación y se purifcó mediante lavados sucesivos con agua acidulada,que resultó ser una mezcla de ésteres metílicos de los ácidos linoleico (48,40%), palmítico (36,21%),esteárico (8,69%) y oleico (6,69%), cuyas propiedades se ajustan a los requerimientos de las normasASTM D 6751 y EN 14214 .
{"title":"Producción de biodiésel a partir de las grasas extraídas de la borra de café: esterifcación con H2SO4 y transesterifcación con KOH","authors":"Cateryna Aiello Mazzarri, Yenmilet Salazar, Aidin Urribarrí, Elsy Arenas Dávila, John Sánchez Fuentes, F. Ysambertt","doi":"10.18359/rcin.2899","DOIUrl":"https://doi.org/10.18359/rcin.2899","url":null,"abstract":"La búsqueda de materias primas no alimenticias es uno de los principales retos en la producción de biocombustibles. Para biodiésel, las investigaciones se orientan hacia el uso de cultivosno convencionales, así como hacia residuos o desechos con alto contenido de grasas y aceites. Laborra de café contiene una buena proporción de grasas y es un residuo comercial y doméstico. Eneste trabajo, se evaluó la producción de biodiésel utilizando las grasas extraídas de la borra del cafémediante un proceso en dos etapas. Las grasas extraídas de la borra de café con ebullición a reflujocon hexano como solvente presentaron una elevada acidez, 32,07 ± 0,01% (70,24 ± 0,03 mg KOH/ggrasa), lo que indica un alto contenido de ácidos grasos libres (AGL). Primero, las grasas se esterifcaron a 60ºC y 100 rpm, variando las condiciones de reacción. A las mejores condiciones, concentraciónde H2SO4 al 0,7%, RMG:MeOH de 1:6 durante 120 min, la acidez disminuyó por debajo del 1%, conel 94,92% de conversión AGL a ésteres metílicos. Se sometieron a un proceso de transesterifcacióncon KOH (1,5% m/v) en presencia de metanol (RMG:MeOH de 1:15) a 60ºC y 100 rpm durante 30 min.El biodiésel se separó por decantación y se purifcó mediante lavados sucesivos con agua acidulada,que resultó ser una mezcla de ésteres metílicos de los ácidos linoleico (48,40%), palmítico (36,21%),esteárico (8,69%) y oleico (6,69%), cuyas propiedades se ajustan a los requerimientos de las normasASTM D 6751 y EN 14214 .","PeriodicalId":31201,"journal":{"name":"Ciencia e Ingenieria Neogranadina","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-08-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47338007","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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