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Impacto del uso de un sillín de bicicleta inestable en la eficiencia energética y la actividad muscular en una prueba de ejercicio submáximo en sujetos sanos
(Universidad de Chile, 2020)
posibilita la utilización del oxígeno durante la ejecución de una tarea específica, permitiendo usar el mayor tiempo posible las reservas energéticas de quien está realizando el ejercicio. Otro componente importante de la condición física es la estabilidad...
Physical activity allows to maintain the health of the population, prevent and treat diseases through effects that occur during and after exercise. One of the components of the physical fitness is cardiorespiratory capacity, which allows the use of oxygen during the execution of a specific task, allowing the energy reserves of the person performing the exercise to be used as long as possible. Another important component of the physical fitness is body stability, allowing to optimally develop daily life and sports activities. One of the ways to train stability is through exercises on unstable surfaces, which have become increasingly popular, both for rehabilitation and for physical training. The objective of this master's thesis is to compare the results of energy expenditure, muscle activity and heart rate variability while pedaling in a cycloergometer at a constant submaximal load, when using a conventional bicycle saddle versus an unstable saddle prototype. Studies indicate that there is an increase in oxygen consumption and muscle activity in exercises performed on unstable bases if compared to exercises on stable bases, so it is postulated to the following hypothesis: The unstable saddle prototype in cycloergometer generates greater global energy expenditure and greater activity in the trunk stabilizing muscles than the common bicycle saddle at a constant load. The assessments of this research took place in the Exercise Physiology Laboratory of the Department of Kinesiology of the Faculty of Medicine of the University of Chile. Project No. 190-2019 approved by the Research Ethics Committee in human beings of the Faculty of Medicine of the University of Chile. The subjects randomized to the stable or unstable condition on a cycle ergometer at a constant submaximal load, where data were taken on the variables of oxygen consumption, minute ventilation, ventilatory equivalents of oxygen and carbon dioxide, amplitude of activity. and neuromuscular shock frequency and heart rate variability at rest before exercise, during the initial condition with one type of saddle selected at random, rest between conditions and finally with the other type of saddle according to what was selected in the initial option. When comparing the stable condition with the unstable one, the following results were obtained; using the unstable condition in gas analysis generates a significant increase in oxygen consumption and in the area under the minute ventilation curve. In the variables of heart rate variability, when using the unstable condition, a significant increase in heart rate is obtained. When using the unstable condition and comparing it with the stable condition in the complete pedaling cycle, there is a significant increase in the percentage of neuromuscular electrical activity with respect to rest, for the dominant rectus abdominis, dominant spinal erector, nondominant spinal erector and non-dominant lateral. It is concluded that the use of the unstable saddle generates an increase in energy expenditure, therefore, the use of the unstable saddle could be considered as a useful tool for preparing future training plans aimed at increasing energy expenditure, in the shortest possible time to submaximal intensity. Future research could contribute with different biomechanical analyzes. As also, with the variation of different pedaling intensities....
Physical activity allows to maintain the health of the population, prevent and treat diseases through effects that occur during and after exercise. One of the components of the physical fitness is cardiorespiratory capacity, which allows the use of oxygen during the execution of a specific task, allowing the energy reserves of the person performing the exercise to be used as long as possible. Another important component of the physical fitness is body stability, allowing to optimally develop daily life and sports activities. One of the ways to train stability is through exercises on unstable surfaces, which have become increasingly popular, both for rehabilitation and for physical training. The objective of this master's thesis is to compare the results of energy expenditure, muscle activity and heart rate variability while pedaling in a cycloergometer at a constant submaximal load, when using a conventional bicycle saddle versus an unstable saddle prototype. Studies indicate that there is an increase in oxygen consumption and muscle activity in exercises performed on unstable bases if compared to exercises on stable bases, so it is postulated to the following hypothesis: The unstable saddle prototype in cycloergometer generates greater global energy expenditure and greater activity in the trunk stabilizing muscles than the common bicycle saddle at a constant load. The assessments of this research took place in the Exercise Physiology Laboratory of the Department of Kinesiology of the Faculty of Medicine of the University of Chile. Project No. 190-2019 approved by the Research Ethics Committee in human beings of the Faculty of Medicine of the University of Chile. The subjects randomized to the stable or unstable condition on a cycle ergometer at a constant submaximal load, where data were taken on the variables of oxygen consumption, minute ventilation, ventilatory equivalents of oxygen and carbon dioxide, amplitude of activity. and neuromuscular shock frequency and heart rate variability at rest before exercise, during the initial condition with one type of saddle selected at random, rest between conditions and finally with the other type of saddle according to what was selected in the initial option. When comparing the stable condition with the unstable one, the following results were obtained; using the unstable condition in gas analysis generates a significant increase in oxygen consumption and in the area under the minute ventilation curve. In the variables of heart rate variability, when using the unstable condition, a significant increase in heart rate is obtained. When using the unstable condition and comparing it with the stable condition in the complete pedaling cycle, there is a significant increase in the percentage of neuromuscular electrical activity with respect to rest, for the dominant rectus abdominis, dominant spinal erector, nondominant spinal erector and non-dominant lateral. It is concluded that the use of the unstable saddle generates an increase in energy expenditure, therefore, the use of the unstable saddle could be considered as a useful tool for preparing future training plans aimed at increasing energy expenditure, in the shortest possible time to submaximal intensity. Future research could contribute with different biomechanical analyzes. As also, with the variation of different pedaling intensities....
Estudio de la generación eléctrica por la vía nuclear en Chile
(Universidad de Chile, 2021)
gases de efecto invernadero emitidos por los consumos individuales de hogar, vehículos, fábricas y plantas energéticas. En este proceso de disminuir las emisiones, los combustibles convencionales son reemplazados por energía eléctrica, con lo que la...
Aprovechamiento Hidroeléctrico de las Mareas y su Posible Desarrollo en Chile
(Universidad de Chile, 2008)
explotación energética de este recurso
se estudia la eficiencia energética de las distintas tecnologías analizando su factor de planta y
el costo de la energía producida, se analiza la central mareomotriz más emblemática que es la
central de La Rance, Francia...
Modelamiento térmico de una granja solar fotovoltaica desde la perspectiva de sistemas ciberfísicos
(Universidad de Chile, 2017)
La crisis mundial medioambiental actual ha llevado a diversas naciones a masificar el uso de energías renovables no convencionales como la solar con tal de purificar su matriz energética.
Los gradientes de temperatura entre las distintas celdas...
Planta Minera Quellaveco: Desarrollo de un Modelo de Eficiencia Energética
(Universidad de ChileCyberDocs, 2010)
La Eficiencia Energética es el conjunto de acciones que permiten optimizar la relación entre la cantidad de energía consumida y los productos obtenidos. Dado que en el último tiempo ha existido un aumento sostenido en el precio de la energía...
Eficiencia fotoquímica en hojas de distintas edades en naranjo (Citrus sinensis (L.) Osbeck) y vid (Vitis vinifera L.)
(Universidad de Chile, 2011)
En el presente estudio, se determinó: la eficiencia energética de los fotosistemas II (PSII) en naranjo y vid, por medio del quenching fotoquímico (qP) quenching no-fotoquímico (qN), la proporción de energía absorbida por las antenas de clorofila y...
Having as a goal the characterization of the fluorometrics answers between leaves of different microclimates conditions at canopy of a deciduous species, the vineyard, versus an evergreen species, the orange tree. The investigation was done under the 2008-2009 seasons, in five Navel oranges trees of an orange orchard and five vine of the Chardonnay vineyard. Both were conducted in a North/South orientation, located in Cerrillos de Tamaya, Province of Limari, Chile. The investigation compared the fluorometrics answers: photochemical quenching (qP), non photochemical quenching (qN), the proportion of energy absorbed by the chlorophyl antennae, and then sent to the open centers reaction of the photosystem II (Fv’/Fm’) and effective quantum yield of photosystem II (ΦPSII). Considering the factor of the sunlight exposition of the leaves, East and West, within the canopy of the plants. Likewise, the age factor of the leaves; in the vineyard the age separation is among the leaves located in the 4th and 12th bunch toward the distal extreme of the bud. In the orange tree, the age separation is between the leaves formed during the summer 2007-2008 in relationship to the leaves formed in the springtime in 2008. In photosynthetic photons flux density (PPFD) incident in each leaf was measured with a PAR sensor. The aim was to generate the same PPFD and in so doing, it was possible to register the fluorometrical answers. This experiment was performed in the morning, noon and afternoon hours, in three different dates. Simultaneously a sampling of the specific weight of leaves (PEH) was done in both species, for both factors, i.e., exposition and age. This study demonstrates that the orange tree has an ability to modify its answers in fluorescence, according to the microclimate of the canopy, where its leaves are developed, which is not the situation observed in the grape plant....
Having as a goal the characterization of the fluorometrics answers between leaves of different microclimates conditions at canopy of a deciduous species, the vineyard, versus an evergreen species, the orange tree. The investigation was done under the 2008-2009 seasons, in five Navel oranges trees of an orange orchard and five vine of the Chardonnay vineyard. Both were conducted in a North/South orientation, located in Cerrillos de Tamaya, Province of Limari, Chile. The investigation compared the fluorometrics answers: photochemical quenching (qP), non photochemical quenching (qN), the proportion of energy absorbed by the chlorophyl antennae, and then sent to the open centers reaction of the photosystem II (Fv’/Fm’) and effective quantum yield of photosystem II (ΦPSII). Considering the factor of the sunlight exposition of the leaves, East and West, within the canopy of the plants. Likewise, the age factor of the leaves; in the vineyard the age separation is among the leaves located in the 4th and 12th bunch toward the distal extreme of the bud. In the orange tree, the age separation is between the leaves formed during the summer 2007-2008 in relationship to the leaves formed in the springtime in 2008. In photosynthetic photons flux density (PPFD) incident in each leaf was measured with a PAR sensor. The aim was to generate the same PPFD and in so doing, it was possible to register the fluorometrical answers. This experiment was performed in the morning, noon and afternoon hours, in three different dates. Simultaneously a sampling of the specific weight of leaves (PEH) was done in both species, for both factors, i.e., exposition and age. This study demonstrates that the orange tree has an ability to modify its answers in fluorescence, according to the microclimate of the canopy, where its leaves are developed, which is not the situation observed in the grape plant....
Informe de Competitividad Mundial 2007 IMD (Suiza)
(Departamento de Administración Facultad de Economía y Negocios, 2007-05)
Económico
Eficiencia del
Gobierno
Eficiencia en los
Negocios
Infraestructura y
Conocimiento
Ranking de Competitividad 2007
IMD – Universidad de Chile
Ranking de Competitividad 2007 IMD – Universidad de Chile
Países con menos de 20 millones hab...
claves para el desarrollo de la competitividad Educación, Ciencia y Tecnología Evolución de Chile por Factor DESEMPEÑO ECONOMICO EFICIENCIA GUBERNAMENTAL EFICIENCIA EN LOS NEGOCIOS INFRAESTRUCTURA Y CONOCIMIENTO Desempeño Económico -11 2 13 Precios +3 38...
claves para el desarrollo de la competitividad Educación, Ciencia y Tecnología Evolución de Chile por Factor DESEMPEÑO ECONOMICO EFICIENCIA GUBERNAMENTAL EFICIENCIA EN LOS NEGOCIOS INFRAESTRUCTURA Y CONOCIMIENTO Desempeño Económico -11 2 13 Precios +3 38...
Evaluación de las emisiones de gases de efecto invernadero en una vivienda social tipo para la incorporación del impacto de cambio climático a la reglamentación térmica nacional
(Universidad de Chile, 2015)
la envolvente de las viviendas (además de algunas otras exigencias), sin explicitar consecuencias en algunos ámbitos, como por ejemplo el energético y medio ambiental. Como principales resultados obtenidos se pueden mencionar que la demanda energética...
Mecanismos de empoderamiento del consumidor final de energía eléctrica en el mercado eléctrico chileno
(Universidad de Chile, 2022)
cuatro soluciones con las mejores oportunidades socioambientales, regulatorias, de mercado y de recursos disponibles: eficiencia energética, generación distribuida, gestión del autoconsumo y gestión de demanda. A cada solución se le diseña una propuesta...
Análisis comparativo y aplicabilidad sobre el consumo y demanda de energía para edificios de distintas certificaciones de construcción sustentable en Chile
(Universidad de Chile, 2016)
parecidos entre los países de las certificaciones, la situación energética y políticas energéticas de cada país y los precios de las principales fuentes de energía de cada país. Finalmente se analizan y comparan la información presentada anteriormente, de...