Geomorphological effects of the Chilean tsunami of 2010 on the coast facing the area of maximum slip, revealed by satellite images and field observations: The case of the sandy coastline of La Trinchera, Maule Region

El análisis de imágenes satelitales junto a observaciones de campo, permitieron la identificación y descripción de las consecuencias geomorfológicas que dejó el tsunami de Chile de 2010 en el litoral arenoso La Trinchera, ubicado frente a la zona de máximo slip del terremoto que lo generó. El tsunami abrió breaches y construyó abanicos en cordones litorales y dunas; erosionó dunas vegetadas y formó pedestales; hizo retroceder la línea de costa un centenar de metros; formó flood scours de hasta 350 metros de largo en la ribera sur de los ríos Malaquita y Huenchullami; y erosionó casi en su totalidad la barra litoral del estuario del río Mataquito y parte de la barra del río Huenchullami. Los efectos directos del tsunami y la extensión de su inundación, fueroncontrolados por el tipo de duna dominante, en este caso, las familias de los barjanes y de dunas parabólicas. Con el tiempo se generaron fenómenos cómo la proliferación de aspersiones, transformaciones en la morfología de dunas y la rápida recuperación de la barra del estuario del río Mataquito. Todos estos procesos sugieren una alteración en el intercambio de sedimentos en el sistema playa-duna.The analysis of satellite images together with field observations, allowed the identification and description of the geomorphological consequences of the Chilean tsunami of 2010 in La Trinchera. La Trinchera is a sandy coastline located in front of the area of the earthquake’s maximum slip. The tsunami opened breaches and built fans in beach ridges and dunes; eroded vegetated dunes and formed pedestals; produced a retreat of the coastline of hundreds of meters; formed flood scours up to 350 m long in the southern bank of the Mataquito and Huenchullami rivers; and almost entirely eroded the sand spits of the Mataquito River estuary and part of the sand bar of Huenchullami river. Both the direct effects of the tsunami and the scope of the inundation were controlled by the dominant type of dune which corresponds to barchans and parabolic dunes. Since the tsunami several processes have been observed, such as proliferation of sand sheets, transformations in the morphology of dunes and rapid recovery of the sand spits of the Mataquito River estuary. All of these processes suggest an alteration in the exchange of sediment in the beach-dune system

Sistema agroecológico para la evaluación de la calidad del suelo y la sanidad del cultivo del chile dulce (capsicum annun) en condiciones de invernadero.

Proyecto de Investigación. Instituto Tecnológico de Costa Rica. Vicerrectoría de Investigación y Extensión (VIE). Escuela de Ingeniería Agrícola, 2012La investigación se realizó en el campus de práctica docente, de la Escuela de Ingeniería Agrícola del Instituto Tecnológico de Costa Rica. Específicamente en un invernadero ubicado a 09°55´09,2” Latitud Norte y 83°54´35,5” Longitud Oeste; con una altitud de 1421 metros sobre el nivel del mar. El invernadero tiene forma de arco y monitor en la parte superior de 40 cm. La altura mínima es de 3 m, está cubierto en los laterales con malla antiáfidos. El terreno es de textura arcillosa, con pendiente del orden de 0,5 a 1%. Se cuenta con doce líneas de goteo ubicadas a 1,30 metros entre sí, con una distancia de goteros de 0,40 m. La descarga de los goteros es de 1,6 L/h. En el invernadero se evaluó el agroecosistema de chile dulce mediante indicadores de sostenibilidad utilizando diferentes abonos orgánicos, sales y un testigo absoluto. Se seleccionaron 7 indicadores de calidad del suelo y 6 indicadores de salud del cultivo. Cada indicador se estimó en forma separada y se le asignó un valor de 1 a 10 siendo 1 el valor menos deseado, 5 un valor promedio y 10 el valor más deseado de acuerdo con las características que presenta el suelo o el cultivo según los atributos a observar para cada indicador. Cuando un indicador no era aplicable para la situación simplemente no se midió o se sustituyó por otro que se consideró más relevante. Una vez que se asignaron los valores a cada indicador, se sumaron los valores obtenidos y se dividieron por el número de indicadores observados y se obtuvo un valor promedio de calidad del suelo y otro de salud del cultivo. Las evaluaciones de calidad del suelo o salud del cultivo que fueron menores de 5 se consideraron que estaban por debajo del umbral de sostenibilidad y por lo tanto ameritan manejos que corrijan aquellos indicadores que exhiben valores bajos. Se utilizó un diseño en bloques completos al azar con cuatro tratamientos y tres repeticiones. Para mayor rigurosidad en el análisis estadístico se realizó un submuestreo de seis plantas por subparcela, a la vez se cosechó toda la parcela para obtener datos de producción total. Los resultados obtenidos muestran que los abonos orgánicos favorecen la sostenibilidad de siembra de chile dulce en invernadero. vii La mejor producción se obtuvo con las sales formuladas y la menor producción se obtuvo con el tratamiento de testigo absoluto. El abono orgánico a base de gallinaza con roca fosfórica (abimgra), favoreció el desarrollo de organismos actinomicetos. Para lograr una estabilidad ecológica en el sistema de producción de chile bajo invernaderos, se requiere un mayor tiempo bajo el modelo agroecológico de manejo de abonos orgánicos, debido a que algunos indicadores evaluados después de un año no alcanzaron el umbral ecológico de sostenibilidad, tal es el caso de profundidad del suelo y actividad biológica.The research was conducted on the teaching practice field of Agricultural Engineering School of Technological Institute of Costa Rica. Specifically in a greenhouse located at 09°55'09,2" North Latitude and 83°54'35,5" West Longitude, with an altitude of 1421 meters above sea level. The greenhouse is arc-shaped with a monitor on top of 40 cm. The minimum height is 3 m, is covered with anti-aphid mesh through all its sides. The soil texture is clay, with a slope of about 0,5 to 1%. It has twelve drip lines located at 1,30 meters apart, with a distance between drippers of 0,40 m. At the greenhouse it was evaluated the agro-ecosystem of pepper trough sustainability indicators using different organic fertilizers, salts and an absolute baton. There were selected 7 soil quality indicators and 6 crop health indicators were chosen. Each indicator was estimated separately and it was assigned to it a value from 1 to 10, with 1 being the least desirable, 5 an average value and 10 the desired value according to the features found in the soil or growing as attributes to observe for each indicator. When an indicator was not applicable to the situation it was just not measured or it was replaced with one that was considered more relevant. Once the values were assigned to each indicator, the values obtained were added and divided by the number of indicators observed and obtained an average value of soil quality and other crop health. The evaluations made for soil quality or crop health lower than 5 were considered to be below the threshold of sustainability and so they need a correct handling in order to correct those low values. It was used a randomized design with complete block with four treatments and three replications. For more thoroughness on statistical analysis it was performed subsampling of six plants per subplot, at the same time the hole plot should be harvested for total production data The results show that organic fertilizers benefit the sustainability of peppers planting in the greenhouse. The best production was obtained by treatment with formulated salts and the lowest production was obtained with the treatment of absolute baton. The organic manure from chicken excrement with phosphoric rock (Abimgra), favored the development of actinomycetes organisms. To achieve ecological stability on production systems of peppers in greenhouses, it is required more time under the agro-ecological model of organic manure management, because some indicators evaluated after one year did not reach the threshold of ecological sustainability, such as soil depth and biological activity

An adaptive stabilized finite element method for the Darcy's equations with pressure dependent viscosities

This work aims to introduce and analyze an adaptive stabilized finite element method to solve a nonlinear Darcy equation with a pressure-dependent viscosity and mixed boundary conditions. We stated the discrete problem's well-posedness and optimal error estimates, in natural norms, under standard assumptions. Next, we introduce and analyze a residual-based a posteriori error estimator for the stabilized scheme. Finally, we present some two- and three-dimensional numerical examples which confirm our theoretical results

Aplicación de energía solar en unidades productivas agropecuarias : como alternativa al cambio climático y la captura de carbono en Costa Rica : programa local piloto de energía renovable

En la actualidad se debe trabajar en la aplicación de energías limpias tales como energía solar, el uso de biomasa y otras fuentes renovables, como alternativa al cambio climático y la captura local de carbono, para mitigar el efecto de invernadero. El presente trabajo ha logrado diseñar, construir y comenzar a generar datos de interés que muestren el potencialidad de la energía solar en actividades agropecuarias en la región Huetar Norte y Chorotega de Costa Rica a través de sistemas de captación térmico de calentamiento de agua en sistemas termosifónicos y fotovoltaico para la generación de energía. Las unidades productivas en donde se están usando estos sistemas son: lecherías y plantas de producción de quesos. El uso de estos sistemas nos permiten lograr el autoconsumo en energía eléctrica, en la esterilización de equipos de ordeño, pasteurización de la leche, en los sistemas de iluminación, en equipos de refrigeración y por consiguiente bajar la factura de pago de electricidad en estas instalaciones productivas buscando sistemas más amigables con el ambiente y bajar la huella de carbono local y regional. Durante todo el período de trabajo se han monitoreado los parámetros climáticos tales como temperaturas (medias, mínimas y máximas), insolación, irradiación solar, que nos permitan correlacionar datos agroclimáticos con captación de energía solar. Los sistemas disponen de un equipo de transmisión de datos inalámbricos que registran a partir de termopares, el llenado y uso de la energía de los tanques térmicos con diferenciales de temperatura, así como de producción eléctrica y su uso. Se ofrecen los datos de correlación entre producción potencial de energía solar, factura eléctrica, en donde se visualiza la tendencia entre ambas variables, así como la comparación entre instalaciones con y sin el sistema, con sus respectivos modelos matemáticos. Estos sistemas finalmente nos acercan a una producción sostenible en Costa Rica, así como una reducción importante de la huella de carbono en la los sistemas de producción animal en el país.Fil: Araya Rodríguez, Freddy. Instituto Tecnológico de Costa Rica. Sede Regional de San CarlosFil: Guzmán Hernández, Tomas. Instituto Tecnológico de Costa Rica. Sede Regional de San CarlosFil: Moreira, Cristian. Instituto Tecnológico de Costa Rica. Sede Regional de San Carlo

An adaptive multiscale hybrid-mixed method for the Oseen equations

A novel residual a posteriori error estimator for the Oseen equations achieves efficiency and reliability by including multilevel contributions in its construction. Originates from the Multiscale Hybrid Mixed (MHM) method, the estimator combines residuals from the skeleton of the first-level partition of the domain, along with the contributions from element-wise approximations. The second-level estimator is local and infers the accuracy of multiscale basis computations as part of the MHM framework. Also, the face-degrees of freedom of the MHM method shape the estimator and induce a new face-adaptive procedure on the mesh’s skeleton only. As a result, the approach avoids re-meshing the first-level partition, which makes the adaptive process affordable and straightforward on complex geometries. Several numerical tests assess theoretical results

Convergence analysis of pressure reconstruction methods from discrete velocities

Magnetic resonance imaging allows the measurement of the three-dimensional velocity field in blood flows. Therefore, several methods have been proposed to reconstruct the pressure field from such measurements using the incompressible Navier- Stokes equations, thereby avoiding the use of invasive technologies. However, those measurements are obtained at limited spatial resolution given by the voxel sizes in the image. In this paper, we propose a strategy for the convergence analysis of state-of-the-art pressure reconstruction methods. The methods analyzed are the so-called Pressure Poisson Estimator (PPE) and Stokes Estimator (STE). In both methods, the right-hand side corresponds to the terms that involving the field velocity in the Navier- Stokes equations, with a piecewise linear interpolation of the exact velocity. In the theoretical error analysis, we show that many terms of different order of convergence appear. These are certainly dominated by the lowest-order term, which in most cases stems from the interpolation of the velocity field. However, the numerical results in academic examples indicate that only the PPE may profit of increasing the polynomial order, and that the STE presents a higher accuracy than the PPE, but the interpolation order of the velocity field always prevails. Furthermore, we compare the pressure estimation methods on real MRI data, assessing the impact of different spatial resolutions and polynomial degrees on each method. Here, the results are consistent with the academic test cases in terms of sensitivity to polynomial order as well as the STE showing to be potentially more accurate when compared to reference pressure measurements.</p

Convergence analysis of pressure reconstruction methods from discrete velocities

Magnetic resonance imaging allows the measurement of the three-dimensional velocity field in blood flows. Therefore, several methods have been proposed to reconstruct the pressure field from such measurements using the incompressible Navier- Stokes equations, thereby avoiding the use of invasive technologies. However, those measurements are obtained at limited spatial resolution given by the voxel sizes in the image. In this paper, we propose a strategy for the convergence analysis of state-of-the-art pressure reconstruction methods. The methods analyzed are the so-called Pressure Poisson Estimator (PPE) and Stokes Estimator (STE). In both methods, the right-hand side corresponds to the terms that involving the field velocity in the Navier- Stokes equations, with a piecewise linear interpolation of the exact velocity. In the theoretical error analysis, we show that many terms of different order of convergence appear. These are certainly dominated by the lowest-order term, which in most cases stems from the interpolation of the velocity field. However, the numerical results in academic examples indicate that only the PPE may profit of increasing the polynomial order, and that the STE presents a higher accuracy than the PPE, but the interpolation order of the velocity field always prevails. Furthermore, we compare the pressure estimation methods on real MRI data, assessing the impact of different spatial resolutions and polynomial degrees on each method. Here, the results are consistent with the academic test cases in terms of sensitivity to polynomial order as well as the STE showing to be potentially more accurate when compared to reference pressure measurements.</p

Convergence analysis of pressure reconstruction methods from discrete velocities

Magnetic resonance imaging allows the measurement of the three-dimensional velocity field in blood flows. Therefore, several methods have been proposed to reconstruct the pressure field from such measurements using the incompressible Navier- Stokes equations, thereby avoiding the use of invasive technologies. However, those measurements are obtained at limited spatial resolution given by the voxel sizes in the image. In this paper, we propose a strategy for the convergence analysis of state-of-the-art pressure reconstruction methods. The methods analyzed are the so-called Pressure Poisson Estimator (PPE) and Stokes Estimator (STE). In both methods, the right-hand side corresponds to the terms that involving the field velocity in the Navier- Stokes equations, with a piecewise linear interpolation of the exact velocity. In the theoretical error analysis, we show that many terms of different order of convergence appear. These are certainly dominated by the lowest-order term, which in most cases stems from the interpolation of the velocity field. However, the numerical results in academic examples indicate that only the PPE may profit of increasing the polynomial order, and that the STE presents a higher accuracy than the PPE, but the interpolation order of the velocity field always prevails. Furthermore, we compare the pressure estimation methods on real MRI data, assessing the impact of different spatial resolutions and polynomial degrees on each method. Here, the results are consistent with the academic test cases in terms of sensitivity to polynomial order as well as the STE showing to be potentially more accurate when compared to reference pressure measurements.</p

Diferencias en los patrones motores de los alumnos de cuarto básico según la cantidad de horas de educación física durante la semana de dos colegios del sector oriente de Santiago

Tesis (Profesor de Educación Física para la Enseñanza Básica, Licenciado en Educación)El objetivo de este estudio fue analizar los patrones motores en hombres y mujeres de diferentes rangos etarios en la población de los alumnos de cuarto básico que realizan las clases de educación física de los dos colegios del sector oriente de la comuna de Santiago. Este estudio se aplicó a un total de 72 hombres y 65 mujeres entre los rangos etarios entre 9 y 10 años aproximadamente, quienes participaron de forma voluntaria bajo su conocimiento con el fin de evidenciar las posibles mejoras que se obtengan con los resultados del test y así poder repicarlo en los otros niveles de los mismos colegios, permitiéndoles saber el nivel de los patrones motores de cada alumno. Para así finalmente poder determinar si el test aplicado cumple con los requisitos establecidos y los estándares que cada niño debe tener según el nivel de los patrones motores

Bibliometric analysis of studies on family firms

Several authors have highlighted the importance of family firms in the worldwide generation of wealth, wellbeing, and employment. Recently, the importance of family firms has resulted in the proliferation of many academic works in prestigious journals. Hence, studying their development and evolution is deemed necessary. This study conducts a bibliometric analysis of the literature on family firms to show the research trends and guide researchers in their work; it is conducted using a detailed and systematic study of the scientific production of papers on family firms published in the Web of Science (WoS) between 1975 and May 2020. Its contributions are as follows. First, it consolidates family firms as an area of research, which reflects on several papers focusing on this topic (1990 papers published in the WoS database, 55982 total citations). Second, it finds that family firm research has mainly developed in the last few years. Third, it discovers that Kellermanns and Chrisman are the most relevant authors in this field. Fourth, it suggests that the most influential journal is Family Business Review. Fifth, it finds that that the Mississippi State University is the most renowned family firm research institution. Sixth, it discovers that the United States has the highest production in the field. Finally, the bibliometric map identifies four clusters, the most relevant being the family firm theory and its evolution