332 research outputs found
Subduction Zone Dynamics and Forearc Tectonostratigraphic Evolution: Talara Basin, northwestern Peru
Dinámica de zonas de subducción y evolución tectono-estratigráfica de antearco: cuenca Talara, noroeste del Perú
Forearc basins are important archives for understanding the tectonic evolution of the plate margin and subduction zone through deep time because they preserve a tectonostratigraphic record of temporal and spatial interactions of eustasy, sediment supply, climate, basin physiography and tectonism. However, forearc basins have received less attention than rift and foreland basins, due to the limited number of exposed examples and classification traditionally restricted to accretionary margins. The Talara Basin in the northern Peruvian forearc, where the oceanic Nazca plate is being subducted beneath the continental South American plate, is a well-known example of a subduction-erosion margin, where the edge of the continental plate is consumed over time and accretionary processes play a minor role. From the Late Cretaceous to the Eocene, stratigraphic units from deep water to fluvial environments comprise a 9 km-thick basin fill that has been episodically deformed by extensional faulting due to forearc vertical movements produced by subduction. This work aims to characterise the spatial and temporal behaviour of subduction and how these processes are recorded in and affect the evolution of the forearc basin. The sequence stratigraphic approach is based on the integration of outcrop, well and seismic data sets. Sedimentology and analysis of stratal stacking patterns and key stratigraphic surfaces, integrated with tectonic studies show that the Eocene Parià ±as Formation comprises three depositional sequences of fluvio-deltaic deposits that form a highstand sequence set. The succession is capped by a previously unrecognised composite sequence boundary marked by a regional palaeosol and overlain by the transgressive sequence set of the Chacra Formation. The composite sequence boundary may indicate the presence of a lowstand sequence set offshore. This integrated PhD project identified tectonically-enhanced/driven regressions and transgressions through the Eocene. Down-dip and across-strike system asymmetry was a response to uplift and extensional collapse events related to periods of locking and release of the subduction interface. These observations highlight the importance of a close temporal and spatial relationship between plate boundary and basin - a relationship unique to forearc basins, with worldwide application.El área de estudio es la cuenca Talara, localizada en el norte del antearco peruano, en la margen convergente entre las placas de Nazca y Sudamérica. Los principales análisis realizados en este trabajo consisten en la interpretación geológica de sísmica de reflexión y sus atributos, análisis y correlación de registros de pozo, descripción de núcleos, muestreo y levantamiento estratigráfico de afloramientos, análisis bioestratigráfico, y petrografía de secciones delgadas. Estos análisis a multi-escala (cuenca–microscopio) están basados en la integración de los datos empleados, tanto en tierra como costa afuera. La motivación fundamental de este trabajo es abordar la brecha de conocimiento sobre cómo el proceso de subducción influye en la estratigrafía secuencial de antearco, especialmente en escenarios de subducción con erosión, ya que el grado de influencia de los factores que controlan la sedimentación en márgenes convergentes tectónicamente activas no está bien identificado como en otras cuencas, debido a la falta de previos trabajos. Los objetivos específicos de este estudio son tres: (i) caracterizar y clasificar los procesos de subducción de la margen continental del norte peruano; (ii) caracterizar la geodinámica de antearco en el tiempo; (iii) construir modelos estratigráfico-secuenciales y tectónicos para entender las condiciones paleoambientales de sedimentación.Perú. Programa Nacional de Becas y Crédito Educativo (Pronabec). Beca Generación del BicentenarioTesi
Tiempo de vacaciones : Imágenes y prácticas sociales
Las prácticas de las vacaciones, por parte de la familia chilena en el contexto del necesario tiempo de descanso, han sido insuficientemente estudiadas, por lo tanto, veremos que la falta de antecedentes históricos o sociológicos, no será impedimento para abordar el asunto, sino más bien, un interesante desafío para explicar y recordar aquellas escenas que nos ayudarán a reconstruir frescos relatos de tiempos distintos, conocer y describir algunas prácticas sociales ya desaparecidas. De tal manera que el desafío de este trabajo es constituirse en un relato, el de un tiempo ausente a partir de preguntas... menos desconocidas de nuestra identidad. Un primer acercamiento a las evidencias existentes sobre el origen de las vacaciones en Chile, como práctica recreativa apunta a que se habrían iniciado a fines del siglo XIX, y de manera más extendida, alrededor de 1910-20, se adopta el veraneo con fines festivos y de esparcimiento social en las playas del litoral central.Facultad de Humanidades y Ciencias de la Educació
Characterization of unconventional hydrogen flame propagation in narrow gaps
The physical limits of the unconventional flame propagation regimes recently discovered [Veiga-Lopez, Phys. Rev. Lett. 124, 174501 (2020)PRLTAO0031-900710.1103/PhysRevLett.124.174501] are analyzed. These regimes appear in combustible gaseous mixtures approaching the lean quenching limit of hydrogen-air flames in narrow gaps. They are characterized by a split of the flame front into a dendritic and a bifurcating set of flame cells separated by nonburned material. A feature selection analysis utilizing dimensionless numbers is applied to reveal the most significant parameters governing the separation between unconventional and traditional flame propagation regimes. It is concluded that (a) the outbreak of unconventional propagation is mostly due to heat losses, (b) the phenomenon is governed by the Peclet number and only appears in thin channels, and (c) the Lewis number does not determine the propagation regime. Additionally, an equation describing the optimal border of the unconventional regime is derived from experiments
Aventura gráfica multijugador
Este proyecto consiste en una aventura gráfica multijugador on-line basado en una historia en
la facultad de informática de la UCM. El diseño del juego está basado en Java Beans Enterprise de
J2EE para la arquitectura cliente servidor y en componentes swing de J2SE para la interfaz gráfica.
Hemos usado el entorno Eclipse como plataforma de desarrollo. Además hemos aprovechado las
siguientes herramientas que vienen integradas en el entorno del servidor JBOSS, Xdoclet, Ant y el
plugin Lomboz.
[ABSTRACT]
This proyect is an on line multi user graphic adventure. It tells a history which happen on UCM
Facultad de Informatica. The game design uses Java Bean Enterprise for server-client architecture
and J2SE swing for graphic interface. We have worked on Eclipse environment which comes with
JBOSS server, Xdoclet, Ant and Lomboz plugin
Optimal configuration of a resource-on-demand 802.11 WLAN with non-zero start-up times
Resource on Demand in 802.11 Wireless LANs is receiving an increasing attention, with its feasibility already proved in practice and some initial analytical models available. However, while these models have assumed that access points (APs) start up in zero time, experimentation has showed that this is hardly the case. In this work, we provide a new model to account for this time in the simple case, of a WLAN formed by two APs where the second AP is switched on/off dynamically to adapt to the traffic load and reduce the overall power consumption, and show that it significantly alters the results when compared to the zero start-up time case, both qualitatively and quantitatively. Our findings show that having a non-zero start up time modifies significantly the trade-offs between power consumption and performance that appears on Resource on Demand solutions. Finally, we propose an algorithm to optimize the energy consumption of the network while guaranteeing a given performance bound.The work of J. Ortín was partly supported by the Centro Universitario de la Defensa through project CUD2013-05, Gobierno de Aragon (research group T98) and the European Social Fund (ESF). The work of P. Serrano and C. Donato was partly supported by the European Commission under grant agreement H2020-ICT-2014-2-671563 (Flex5Gware) and by the Spanish Ministry of Economy and Competitiveness under grant agreement TEC2014-58964-C2-1-R (DRONEXT)
Robust fractional-order control using a decoupled pitch and roll actuation strategy for the I-support soft robot
This article belongs to the Special Issue Applications of Mathematical Models in Engineering.Tip control is a current open issue in soft robotics; therefore, it has received a good amount of attention in recent years. The desirable soft characteristics of these robots turn a well-solved problem in classic robotics, like the end-effector kinematics and dynamics, into a challenging problem. The high redundancy condition of these robots hinders classical solutions, resulting in controllers with very high computational costs. In this paper, a simplification is proposed in the actuation setup of the I-Support soft robot, allowing the use of simple strategies for tip inclination control. In order to verify the proposed approach, inclination step input and trajectory-tracking experiments were performed on a single module of the I-Support robot, resulting in zero output error in all cases, including those where the system was exposed to disturbances. The comparative results of the proposed controllers, a proportional integral derivative (PID) and a fractional order robust (FOPI) controller, validate the feasibility of the proposed approach, showing a clear advantage in the use of the fractional robust controller for the tip inclination control of the I-Support robot compared to the integer order controller.The research leading to these results has received funding from the project Desarrollo de articulaciones blandas para aplicaciones robóticas, with reference IND2020/IND-1739, funded by the Comunidad Autónoma de Madrid (CAM) (Department of Education and Research), from HUMASOFT project, with reference DPI2016-75330-P, funded by the Spanish Ministry of Economy and Competitiveness, and from RoboCity2030-DIH-CM, Madrid Robotics Digital Innovation Hub (Robótica aplicada a la mejora de la calidad de vida de los ciudadanos, FaseIV; S2018/NMT-4331), funded by "Programas de Actividades I+D en la Comunidad de Madrid" and cofunded by Structural Funds of the EU. This work was also funded by the European Union's Horizon 2020 research and innovation programme under grant agreement No. 863212 (PROBOSCIS) and No. 824074 (GROWBOT)
Análisis por elementos finitos del chasis de una motocicleta
El principal objetivo del proyecto consiste en el análisis por elementos finitos del chasis fabricado para la competición Motostudent por parte del equipo MotostudentZGZ-Unizar. La competición se desarrollo a lo largo de 2 cursos académicos, comenzando en el año 2008 y finalizando en Octubre del 2010 con unas jornadas en el circuito de Motorland Aragón donde se puso a prueba los prototipos. Para ello se va a utilizar el programa Abaqus cuyo aprendizaje y manejo se ha profundizado a lo largo de presente Proyecto de Fin de Carrera. Se introducirá en el programa de análisis de elementos finitos una recreación lo más fiel posible de las principales partes que aportan rigidez al conjunto de la motocicleta. Estas partes constituyen la estructura principal o chasis donde se soportan el resto de elementos. El sub-chasis o colín, elemento donde se situará el piloto, la cuna, elemento de sujeción del bloque motor, ya que contábamos con un motor que tenía la necesidad de ser portado y el eje basculante, elemento de unión del chasis con el basculante de la motocicleta. Sobre todos estos elementos, unidos de la manera más próxima a la realidad, se aplicarán tres hipótesis diferentes. Hipótesis desarrolladas al final de la competición y que someten a nuestra motocicleta virtual a situaciones reales que podemos encontrar en el circuito. Las cargas aplicadas en dichas hipótesis fueron desarrolladas por el equipo MotostudentZGZ-Unizar. Esas tres hipótesis que se van a estudiar las situaciones de máxima frenada, el caso de salida de curva y el de impacto con el piano en paso por curva. Dada la naturaleza del proyecto y del entorno en el que ha desarrollado podemos contar con los resultados obtenidos en el circuito y que validan el prototipo desarrollado. Con este documento se podrá conocer lo cerca que se ha estado de los límites de los materiales utilizados para la construcción de dicho prototipo
Contextual factors affecting community participation in leisure and free time persons with disabilities physical
A qualitative descriptive study was conducted with the aim of analyzing the contextual factors that influence community participation in leisure activities and free time in persons with disabilities from physical aged between 30 and 59 years and belonging to the Department Disability Concepcion, Chile. The sample was selected by convenience sampling and consisted of four participants who underwent an open interview applied individually during the period of June 2016.In conclusion, the greater community participation in leisure activities and free time of respondents in the activities arising from specific programs for people with disabilities, in this case from the Department of Disability Concepcion, identifying both environmental and personal factors that influence participation of these activities. In relation to environmental factors, more than half of participants identified: physical space, support and relationships and climate, as factors influencing their participation in such activities. In relation to personal factors, more than half identified: motivation, time, results of the experience and the factors associated with the health condition as factors influencing their participation in such activities
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