Reducción de dimensiones para clasificación de datos multidimensionales usando medidas de información

El enorme desarrollo tecnológico ha creado un concepto de información con áreas extensas de aplicación para tareas referentes al entrenamiento de sistemas automáticos. Este trabajo propone una metodología basada en el análisis de componentes independientes (ICA), que incluye el uso de medidas de información, para realizar reducción de dimensiones en conjuntos de datos multidimensionales. La metodología usa un principio de relevancia, con el fin de hallar la representación reducida mientras se conserva la estructura relacionada a la información inicial. La metodología se compara y se conjuga con un sistema básico de selección de características cuya función de evaluación usa la medida de entropía logrando mejores resultados en la clasificación

Effect of dilute sulfuric acid pretreatment on the physicochemical properties and enzymatic hydrolysis of coffee cut-stems

Coffee-cut stems are a potential fermentable sugars source, which can be upgraded in different value-added products and energy vectors. Nevertheless, there are few reports focused on the acid pretreatment and saccharification processes. Thus, this paper evaluates the effect of the acid pretreatment and saccharification conditions of coffee cut-stems to find the highest sugar yield. Thereafter, the influence of the residence time in the acid pretreatment and the -glucosidase supplementation in the saccharification process were analyzed. The combined severity factor and crystallinity index were used as metrics to evaluate both processes. In all assays, an increase in the crystallinity index was observed. Furthermore, a nonlinear trend of the combined severity factor respect to the residence time in the acid pretreatment was evidenced. The highest sugar yield was 66.75% with a combined severity factor of 1.84. The better saccharification process was achieved at combined severity factor of 2.01 with a digestibility of 43%. The addition of -glucosidase in the enzymatic hydrolysis allows increasing the value to 69.07%. Hence, low temperatures, acid concentrations, and the -glucosidase supplementation allows obtaining a high sugar yield from coffee cut stems.The authors express their gratitude for the financial support to the Programme of ERASMUS + - International Credit Mobility celebrated between the Universidad Nacional de Colombia at Manizales and the University of Minho. The COLCIENCIAS program “Jóvenes Investigadores e Innovadores, Convocatoria 761 de 2016”, the international collaboration project COLCIENCIAS – CONICYT with code PCCI140052, HERMES code 23567 (23876) entitled “Análisis Tecno-económico y Ambiental de Biorefinerías a partir de Residuos Lignocelulósicos con Esquemas de Recirculación de Microorganismos”, the research program entitled “Reconstrucción del tejido social en zonas posconflicto en Colombia” SIGP code: 57579 with the project entitled “Competencias empresariales y de innovación para el desarrollo económico y la inclusión productiva de las regiones afectadas por el conflicto colombiano” SIGP code 58907. Contract number: FP44842-213-2018.info:eu-repo/semantics/publishedVersio

Reducción de dimensiones para clasificación de datos multidimensionales usando medidas de información

El enorme desarrollo tecnológico ha creado un concepto de información con áreas extensas de aplicación para tareas referentes al entrenamiento de sistemas automáticos. Este trabajo propone una metodología basada en el análisis de componentes independientes (ICA), que incluye el uso de medidas de información, para realizar reducción de dimensiones en conjuntos de datos multidimensionales. La metodología usa un principio de relevancia, con el fin de hallar la representación reducida mientras se conserva la estructura relacionada a la información inicial. La metodología se compara y se conjuga con un sistema básico de selección de características cuya función de evaluación usa la medida de entropía logrando mejores resultados en la clasificación

Reducción de dimensiones para clasificación de datos multidimensionales usando medidas de información

El enorme desarrollo tecnológico ha creado un concepto de información con áreas extensas de aplicación para tareas referentes al entrenamiento de sistemas automáticos. Este trabajo propone una metodología basada en el análisis de componentes independientes (ICA), que incluye el uso de medidas de información, para realizar reducción de dimensiones en conjuntos de datos multidimensionales. La metodología usa un principio de relevancia, con el fin de hallar la representación reducida mientras se conserva la estructura relacionada a la información inicial. La metodología se compara y se conjuga con un sistema básico de selección de características cuya función de evaluación usa la medida de entropía logrando mejores resultados en la clasificación

Drainage And Sedimentary Response Of The Northern Andes And The Pebas System To Miocene Strike-slip Tectonics: A Source To Sink Study Of The Magdalena Basin

Miocene strike-slip tectonics was responsible for creating and closing short-lived (ca. 6 Ma) passages and the emergence of isolated topography in the Northern Andes. These geological events likely influenced the migration and/or isolation of biological populations. To better understand the paleogeography of the Miocene hinterland and foreland regions in the Northern Andes, we conducted a source-to-sink approach in the Magdalena Basin. This basin is located between the Central and Eastern Cordilleras of Colombia and contains an ample Miocene record, which includes Lower Miocene fine-grained strata and Middle Miocene to Pliocene coarsening-up strata. Our study presents a new data set that includes detrital U–Pb zircon ages (15 samples), sandstone petrography (45 samples) and low-temperature thermochronology from the Southern Central Cordillera (19 dates); which together with previously published data were used to construct a paleogeographical model of the Miocene hinterland and foreland regions in the Northern Andes. The evolution of the Magdalena Basin during the Miocene was characterized by playa and permanent lake systems at ca. 17.5 Ma, which may be related to a marine incursion into NW South America and western Amazonia. The appearance of Eocene to Miocene volcanic sources in the Honda Group after ca. 16 Ma suggests the development of fluvial passages, which connected the Pacific with the western Amazonia and Caribbean regions. These passages were synchronous with a time of Miocene exhumation and topographic growth (ca. 16 to 10 Ma) in the Central Cordillera and the transition from lacustrine to fluvial deposition in the Magdalena Basin. Middle to Late Miocene strike-slip deformation promoted by oblique plate convergence and the oblique collision of the Panamá-Chocó Block likely explains the synchronous along-strike fragmentation and exhumation in the Central Cordillera

Assessing a low-cost methane sensor quantification system for use in complex rural and urban environments

Low-cost sensors have the potential to facilitate the exploration of air quality issues on new temporal and spatial scales. Here we evaluate a low-cost sensor quantification system for methane through its use in two different deployments. The first was a 1-month deployment along the Colorado Front Range and included sites near active oil and gas operations in the Denver-Julesburg basin. The second deployment was in an urban Los Angeles neighborhood, subject to complex mixtures of air pollution sources including oil operations. Given its role as a potent greenhouse gas, new low-cost methods for detecting and monitoring methane may aid in protecting human and environmental health. In this paper, we assess a number of linear calibration models used to convert raw sensor signals into ppm concentration values. We also examine different choices that can be made during calibration and data processing and explore cross sensitivities that impact this sensor type. The results illustrate the accuracy of the Figaro TGS 2600 sensor when methane is quantified from raw signals using the techniques described. The results also demonstrate the value of these tools for examining air quality trends and events on small spatial and temporal scales as well as their ability to characterize an area – highlighting their potential to provide preliminary data that can inform more targeted measurements or supplement existing monitoring networks