35 resultados para Local tourist system

em Universidad Politécnica de Madrid


Relevância:

80.00% 80.00%

Publicador:

Resumo:

The uncertainty associated to the forecast of photovoltaic generation is a major drawback for the widespread introduction of this technology into electricity grids. This uncertainty is a challenge in the design and operation of electrical systems that include photovoltaic generation. Demand-Side Management (DSM) techniques are widely used to modify energy consumption. If local photovoltaic generation is available, DSM techniques can use generation forecast to schedule the local consumption. On the other hand, local storage systems can be used to separate electricity availability from instantaneous generation; therefore, the effects of forecast error in the electrical system are reduced. The effects of uncertainty associated to the forecast of photovoltaic generation in a residential electrical system equipped with DSM techniques and a local storage system are analyzed in this paper. The study has been performed in a solar house that is able to displace a residential user?s load pattern, manage local storage and estimate forecasts of electricity generation. A series of real experiments and simulations have carried out on the house. The results of this experiments show that the use of Demand Side Management (DSM) and local storage reduces to 2% the uncertainty on the energy exchanged with the grid. In the case that the photovoltaic system would operate as a pure electricity generator feeding all generated electricity into grid, the uncertainty would raise to around 40%.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

El objetivo del proyecto es implantar un sistema de monitorización, con la peculiaridad de encontrarse en alta disponibilidad, esto es, que el servicio (la monitorización de una infraestructura) se preste forma continua y no se vea interrumpido. Dado que el propósito del sistema es monitorizar activamente una infraestructura, ha sido necesario desplegar una infraestructura, además del sistema de monitorización. La infraestructura en cuestión está compuesta por un servidor de documentación, un servidor de base de datos, un servidor de aplicaciones y un servidor web. El sistema de monitorización se ha desplegado en la misma red de área local de esta infraestructura y monitoriza que los servicios prestados por los componentes de esta infraestructura se encuentren operativos y funcionando adecuadamente. Así pues, se tendría un sistema de monitorización local funcional. No obstante, el proyecto plantea un sistema escalable, que esté preparado para el crecimiento de la infraestructura y continúe siendo eficiente. Para ello, sistema de monitorización se encuentre dividido por dos componentes:  Sonda delegada: monitoriza localmente los activos de la infraestructura a monitorizar, es el escenario anteriormente descrito.  Sonda maestra: recibe los resultados de la monitorización realizada, este sistema puede estar desplegado en otra red distinta a la sonda delegada. Este enfoque no solo es escalable, sino también es fiel a la realidad, pues puede darse el caso de que las sondas pertenezcan a distintas infraestructuras e inclusive, distintas organizaciones, y se comuniquen a través de internet, mediante un mecanismo confiable a ser posible. El proyecto plantea que ambas sondas se encuentren en alta disponibilidad (en adelante HA, referente a high availability), y que cada sonda está compuesta por dos equipos (nodos, en adelante). Como se analizará en posteriores capítulos, existen diversas configuraciones que permiten implantar un sistema en HA, la configuración escogida para el proyecto es Activo – Pasivo(los detalles de esta configuración también se explican en posteriores capítulos). Para finalizar, se estudiara la posibilidad de ofrecer respuestas activas en ciertas situaciones y configuraciones adicionales sobre el sistema de monitorización base. Por otro lado, para la implantación del proyecto se ha usado software de código abierto para la virtualización de la infraestructura (Virtual Box y GNS3), los sistemas operativos base (Linux), el sistema de monitorización(Nagios Core) así como el software que implementa la HA (corosync y pacemaker).---ABSTRACT---The aim of the Project is to implement a monitoring system, with the peculiarity of being deployed in high availability, what it is that the service (monitoring infrastructure) is provided continuously and not interrupted. As the purpose of the system is monitoring infrastructure actively, an infrastructure has been deployed, and also the monitoring system. The infrastructure monitored is composed of a documentation server, a server database, an application server and a Web server. The monitoring system has been also deployed on the same LAN of this infrastructure and monitors the services provided by the components of this infrastructure are operational and working as expected. This is a local monitoring system functional. However, the project also proposes a scalable system that is ready for growth of infrastructure and efficient. This is the reason of divide the system in two components:  Slave Component: monitors locally the infrastructure assets to be monitored, this is the scenario described above.  Master Component: get the results from the monitoring, provided by the Slave Component. This system can be deployed in a different network than the slave component. This approach is not only scalable but also a real scenario, as may be the case that the Components belongs to different infrastructures and even, different organizations, also this components can communicate over the Internet, through a reliable mechanism if possible. The project proposes that both Components are deployed in high availability (HA onwards concerning high availability), each Component is composed of two servers (nodes, hereafter). As will be discussed in later chapters, there are several settings available to deploy a system in HA, the configuration chosen for the project is Active - Passive (details of this configuration are also explained in later chapters). Finally the possibility of offering active responses in certain situations and additional settings on the monitoring system will be discussed. On the other hand, for the implementation of the project, open source software has been used, for virtualization infrastructure (Virtual Box and GNS3), code-based operating systems (Linux), the monitoring system (Nagios core), as well as the software that implements the HA (corosync and pacemaker).

Relevância:

80.00% 80.00%

Publicador:

Resumo:

El objetivo de esta Tesis es presentar un método eficiente para la evaluación de sistemas multi-cuerpo con elementos flexibles con pequeñas deformaciones, basado en métodos topológicos para la simulación de sistemas tan complejos como los que se utilizan en la práctica y en tiempo real o próximo al real. Se ha puesto un especial énfasis en la resolución eficiente de aquellos aspectos que conllevan mayor coste computacional, tales como la evaluación de las ecuaciones dinámicas y el cálculo de los términos de inercia. Las ecuaciones dinámicas se establecen en función de las variables independientes del sistema, y la integración de las mismas se realiza mediante formulaciones implícitas de index-3. Esta Tesis se articula en seis Capítulos. En el Capítulo 1 se realiza una revisión bibliográfica de la simulación de sistemas flexibles y los métodos más relevantes de integración de las ecuaciones diferenciales del movimiento. Asimismo, se presentan los objetivos de esta Tesis. En el Capítulo 2 se presenta un método semi-recursivo para la evaluación de las ecuaciones de los sistemas multi-cuerpo con elementos flexibles basado en formulaciones topológicas y síntesis modal. Esta Tesis determina la posición de cada punto del cuerpo flexible en función de un sistema de referencia flotante que se mueve con dicho cuerpo y de las amplitudes de ciertos modos de deformación calculados a partir de un mallado obtenido mediante el Método de Elementos Finitos. Se presta especial atención en las condiciones de contorno que se han de tener en cuenta a la hora de establecer las variables que definen la deformación del cuerpo flexible. El Capítulo 3 se centra en la evaluación de los términos de inercia de los sistemas flexibles que generalmente conllevan un alto coste computacional. Se presenta un método que permite el cálculo de dichos términos basado en el uso de 24 matrices constantes que pueden ser calculadas previamente al proceso de integración. Estas matrices permiten evaluar la matriz de masas y el vector de fuerzas de inercia dependientes de la velocidad sin que sea necesario evaluar la posición deformada de todos los puntos del cuerpo flexible. Se realiza un análisis pormenorizado de dichas matrices con el objetivo de optimizar su cálculo estableciendo aproximaciones que permitan reducir el número de dichos términos y optimizar aún más su evaluación. Se analizan dos posibles simplificaciones: la primera utiliza una discretización no-consistente basada en elementos finitos en los que se definen únicamente los desplazamientos axiales de los nodos; en la segunda propuesta se hace uso de una matriz de masas concentradas (Lumped Mass). Basándose en la formulación presentada, el Capítulo 4 aborda la integración eficiente de las ecuaciones dinámicas. Se presenta un método iterativo para la integración con fórmulas de index-3 basado en la proyección de las ecuaciones dinámicas según las variables independientes del sistema multi-cuerpo. El cálculo del residuo del sistema de ecuaciones no lineales que se ha de resolver de modo iterativo se realiza mediante un proceso recursivo muy eficiente que aprovecha la estructura topológica del sistema. Se analizan tres formas de evaluar la matriz tangente del citado sistema no lineal: evaluación aproximada, numérica y recursiva. El método de integración presentado permite el uso de distintas fórmulas. En esta Tesis se analizan la Regla Trapezoidal, la fórmula BDF de segundo orden y un método híbrido TR-BDF2. Para este último caso se presenta un algoritmo de paso variable. En el Capítulo 5 plantea la implementación del método propuesto en un programa general de simulación de mecanismos que permita la resolución de cualquier sistema multi-cuerpo definiéndolo mediante un fichero de datos. La implementación de este programa se ha realizado tanto en C++ como en Java. Se muestran los resultados de las formulaciones presentadas en esta Tesis mediante la simulación de cuatro ejemplos de distinta complejidad. Mediante análisis concretos se comparan la formulación presentada con otras existentes. También se analiza el efecto del lenguaje de programación utilizado en la implementación y los efectos de las posibles simplificaciones planteadas. Por último, el Capítulo 6 resume las principales conclusiones alcanzadas en la Tesis y las futuras líneas de investigación que con ella se abren. ABSTRACT This Thesis presents an efficient method for solving the forward dynamics of a multi-body sys-tem formed by rigid and flexible bodies with small strains for real-time simulation of real-life models. It is based on topological formulations. The presented work focuses on the efficient solution of the most time-consuming tasks of the simulation process, such as the numerical integration of the motion differential equations and in particular the evaluation of the inertia terms corresponding to the flexible bodies. The dynamic equations are formulated in terms of independent variables of the muti-body system, and they are integrated by means of implicit index-3 formulae. The Thesis is arranged in six chapters. Chapter 1 presents a review of the most relevant and recent contributions related to the modelization of flexible multi-body systems and the integration of the corresponding dynamic equations. The main objectives of the Thesis are also presented in detail. Chapter 2 presents a semi-recursive method for solving the equations of a multi-body system with flexible bodies based on topological formulations and modal synthesis. This Thesis uses the floating frame approach and the modal amplitudes to define the position of any point at the flexible body. These modal deformed shapes are obtained by means of the Finite Element Method. Particular attention has been taken to the boundary conditions used to define the deformation of the flexible bodies. Chapter 3 focuses on the evaluation of the inertia terms, which is usually a very time-consuming task. A new method based on the use of 24 constant matrices is presented. These matrices are evaluated during the set-up step, before the integration process. They allow the calculation of the inertia terms in terms of the position and orientation of the local coordinate system and the deformation variables, and there is no need to evaluate the position and velocities of all the nodes of the FEM mesh. A deep analysis of the inertia terms is performed in order to optimize the evaluation process, reducing both the terms used and the number of arithmetic operations. Two possible simplifications are presented: the first one uses a non-consistent approach in order to define the inertia terms respect to the Cartesian coordinates of the FEM mesh, rejecting those corresponding to the angular rotations; the second approach makes use of lumped mass matrices. Based on the previously presented formulation, Chapter 4 is focused on the numerical integration of the motion differential equations. A new predictor-corrector method based on index-3 formulae and on the use of multi-body independent variables is presented. The evaluation of the dynamic equations in a new time step needs the solution of a set on nonlinear equations by a Newton-Raphson iterative process. The computation of the corresponding residual vector is performed efficiently by taking advantage of the system’s topological structure. Three methods to compute the tangent matrix are presented: an approximated evaluation that considers only the most relevant terms, a numerical approach based on finite differences and a recursive method that uses the topological structure. The method presented for integrating the dynamic equations can use a variety of integration formulae. This Thesis analyses the use of the trapezoidal rule, the 2nd order BDF formula and the hybrid TR-BDF2 method. A variable-time step strategy is presented for the last one. Chapter 5 describes the implementation of the proposed method in a general purpose pro-gram for solving any multibody defined by a data file. This program is implemented both in C++ and Java. Four examples are used to check the validity of the formulation and to compare this method with other methods commonly used to solve the dynamic equations of multi-body systems containing flexible bodies. The efficiency of the programming methodology used and the effect of the possible simplifications proposed are also analyzed. Chapter 6 summarizes the main Conclusions obtained in this Thesis and the new lines of research that have been opened.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Actualmente se reconoce de forma generalizada que la problemática de los barrios más desfavorecidos presenta un trasfondo estructural de magnitud multidimensional que implica a múltiples actores, que requiere respuestas de carácter multiescalar, multidimensional y multiagente y un alto nivel de cooperación institucional y de coordinación entre la diversidad de actores, que pone en cuestión los modelos de gobernanza y gestión urbana tradicionales. Frente a los retos e implicaciones que plantea la noción de espacio como construcción social y los problemas de coordinación detectados que limitan el alcance de la regeneración urbana integrada, en esta investigación se pregunta por los principales elementos que pueden facilitar la dinamización y coordinación de los procesos y se plantea que es preciso aprovechar el propio proceso participativo para reforzar el papel de estos elementos y generar mejores condiciones para la colaboración en un proceso de aprendizaje práctico de formas de análisis e intervención integrada y gestión relacional, que supere los niveles de información y consulta de la práctica participativa habitual. Se centra por tanto la atención en los factores que facilitan la dinamización y coordinación de los procesos (elementos dinamizadores y articuladores), en el nivel de participación social y cooperación institucional en los distintos momentos de la planificación de la estrategia entendida como un proceso continuo de reflexión-acción-reflexión y en aquellas condiciones del modelo de participación que pueden propiciar relaciones estratégicas y mejorar la capacidad de interacción y acción del sistema de actores y relaciones en el proceso de planificación y gestión, que lleva a cuestionar en qué medida los soportes (foros de participación y nodos y ejes de actividad y relación) y el tipo de técnicas (técnicas de dinamización y técnicas de identificación y activación de oportunidades) de los modelos de participación de experiencias concretas pueden fomentar formas de interacción que mejoren la comunicación y la movilización de recursos. Para analizar esta situación en la práctica, se desarrolla un marco conceptual, metodológico y operativo a partir de la contribución de conceptos, teorías y modelos basados en una visión relacional y multidimensional de las dinámicas de desarrollo local integrado. Esta metodología se valida en cuatro casos de referencia a partir de la información de documentos oficiales y de las visiones de la diversidad de actores implicados recogidas a través de una primera consulta a expertos (13) y entrevistas semiestructuradas a representantes de la diversidad de actores implicados (75), que se ha procesado por medio de tres herramientas conceptuales de análisis complementarias desarrolladas a lo largo de la investigación apoyadas en la perspectiva relacional de la reinterpretación actual del espacio y las escalas: el ‘Sistema de acción local’, el ‘Diagrama de momentos’ del proceso de planificación y gestión, y la ‘Matriz de caracterización’ del modelo de participación. La evaluación y la comparativa de los casos según el método de análisis evidencian la importancia del papel ejercido por los elementos articuladores (actores y organismos de enlace, espacios de encuentro y acción, y los significados y visiones compartidas) y dinamizadores (el capital social y las capacidades institucionales propiciadas en redes de colaboración) a la hora de facilitar la colaboración entre las distintas instituciones responsables, reforzar las relaciones entre actores, grupos y entidades del barrio, y mejorar los problemas de convivencia vecinal, y en definitiva, de mejorar las posibilidades de los diferentes actores urbanos de implicarse de manera activa. Además, las fórmulas alternativas que se han puesto en marcha en los distintos casos frente a las dificultades que presenta la administración a la hora de trabajar por proyectos y el resto de actores de colaborar de forma constructiva, han supuesto un importante proceso de aprendizaje y práctica en formas de participación y colaboración. ABSTRACT It is widely accepted that the current situation of multi-deprived neighborhoods has a structural and a multidimensional basis involving multiple actors that calls for multiscale, multidimensional and multiagent solutions and requires a high level of institutional cooperation and a great deal of coordination between different actors. This calls into question traditional governance and management models. In order to cope with the challenges and implications of the idea of the social construction of space and these coordination requirements that compromise the scope of integrated urban regeneration strategies, this research focuses on the main elements and factors that facilitate the mobilization and coordination of the regeneration processes, and recognizes the importance of participation processes facilitating better social, communication and collaboration skills in a practical learning process of integrated analysis and urban regeneration interventions and relational governance mechanisms going beyond mere information and consultation levels. Thus, the study focuses on the principal factors which facilitate the mobilization and coordination of integrated area regeneration, the level of social participation and institutional cooperation at different planning moments in a continuous process of reflection-action-reflection, and the conditions under which the participation process may promote strategic relationships and improve the performance of the system of actors and relationships in the planning and management process. This questions to what extent the supports (participation arenas and activity nodes and axis) and the type of techniques (participation encouragement and opportunities identification and activation techniques) considered in participation models had led to a level of interaction that has improved communication and resource mobilization capabilities. In order to analyze this situation in practice, a conceptual, methodological and operational framework is developed, which considers the contributions of the review of concepts, theories and models based on a relational and multidimensional view of local development dynamics. This methodology is validated in four representative case studies in view of official documents and the contributions of diverse stakeholders gathered through a first consultation to experts (13) and semi-structured interviews to representatives of the diversity of actors involved (75). This data has been processed by three complementary analytical tools developed during the research, based on the relational perspective of the current reinterpretation of space and scales: the 'Local Action System', the 'Diagram of planning moments', and the 'Characterization matrix of the participation model'. The comparative evaluation of the four case studies carried out using the analytical method developed during the project, shows the importance of the availability and the role of linkage elements (actors and organizations, collective spaces and shared visions) and drivers (social capital and institutional capacities generated through collaborative networks) in facilitating the collaboration among all responsible institutions, in promoting and strengthening relations between actors, groups and neighborhood organizations, and in improving the conviviality and social cohesion conditions, and ultimately in fostering the possibilities of diversity of urban actors to engage and participate actively in the transformation process, increasing accordingly the options for change. In addition, despite all the difficulties, these practices have implemented alternative formulas addressing the limitations of the administration in working by projects and not by competences and of the stakeholders in collaborating in a constructive way. The development and implementation of these participatory formulas has been an important learning process.

Relevância:

40.00% 40.00%

Publicador:

Resumo:

In this paper, we study a system of partial differential equations describing the evolution of a population under chemotactic effects with non-local reaction terms. We consider an external application of chemoattractant in the system and study the cases of one and two populations in competition. By introducing global competitive/cooperative factors in terms of the total mass of the populations, weobtain, forarangeofparameters, thatanysolutionwithpositive and bounded initial data converges to a spatially homogeneous state with positive components. The proofs rely on the maximum principle for spatially homogeneous sub- and super-solutions.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

This paper describes the development of an Advanced Speech Communication System for Deaf People and its field evaluation in a real application domain: the renewal of Driver’s License. The system is composed of two modules. The first one is a Spanish into Spanish Sign Language (LSE: Lengua de Signos Española) translation module made up of a speech recognizer, a natural language translator (for converting a word sequence into a sequence of signs), and a 3D avatar animation module (for playing back the signs). The second module is a Spoken Spanish generator from sign-writing composed of a visual interface (for specifying a sequence of signs), a language translator (for generating the sequence of words in Spanish), and finally, a text to speech converter. For language translation, the system integrates three technologies: an example-based strategy, a rule-based translation method and a statistical translator. This paper also includes a detailed description of the evaluation carried out in the Local Traffic Office in the city of Toledo (Spain) involving real government employees and deaf people. This evaluation includes objective measurements from the system and subjective information from questionnaires. Finally, the paper reports an analysis of the main problems and a discussion about possible solutions.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

A clear statement in these lines textually cited (Byers et al., 1938) defines the framework of this special issue: “True soil is the product of the action of climate and living organism upon the parent material, as conditioned by the local relief. The length of time during which these forces are operative is of great importance in determining the character of the ultimate product. Drainage conditions are also important and are controlled by local relief, by the nature of the parent material or underlying rock strata, or by the amount of precipitation in relation to rate of percolation and runoff water. There are, therefore, five principal factors of soil formation: Parent material, climate, biological activity, relief and time. These soil forming factors are interdependent, each modifying the effectiveness of the others.” Due to these various processes associated to its formation and genesis soil dynamics reveals high complexity that creates several levels of structure using this term in a broad sense

Relevância:

30.00% 30.00%

Publicador:

Resumo:

In this paper we present an adaptive multi-camera system for real time object detection able to efficiently adjust the computational requirements of video processing blocks to the available processing power and the activity of the scene. The system is based on a two level adaptation strategy that works at local and at global level. Object detection is based on a Gaussian mixtures model background subtraction algorithm. Results show that the system can efficiently adapt the algorithm parameters without a significant loss in the detection accuracy.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

The integration of powerful partial evaluation methods into practical compilers for logic programs is still far from reality. This is related both to 1) efficiency issues and to 2) the complications of dealing with practical programs. Regarding efnciency, the most successful unfolding rules used nowadays are based on structural orders applied over (covering) ancestors, i.e., a subsequence of the atoms selected during a derivation. Unfortunately, maintaining the structure of the ancestor relation during unfolding introduces significant overhead. We propose an efficient, practical local unfolding rule based on the notion of covering ancestors which can be used in combination with any structural order and allows a stack-based implementation without losing any opportunities for specialization. Regarding the second issue, we propose assertion-based techniques which allow our approach to deal with real programs that include (Prolog) built-ins and external predicates in a very extensible manner. Finally, we report on our implementation of these techniques in a practical partial evaluator, embedded in a state of the art compiler which uses global analysis extensively (the Ciao compiler and, specifically, its preprocessor CiaoPP). The performance analysis of the resulting system shows that our techniques, in addition to dealing with practical programs, are also significantly more efficient in time and somewhat more efficient in memory than traditional tree-based implementations.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Los estudios realizados hasta el momento para la determinación de la calidad de medida del instrumental geodésico han estado dirigidos, fundamentalmente, a las medidas angulares y de distancias. Sin embargo, en los últimos años se ha impuesto la tendencia generalizada de utilizar equipos GNSS (Global Navigation Satellite System) en el campo de las aplicaciones geomáticas sin que se haya establecido una metodología que permita obtener la corrección de calibración y su incertidumbre para estos equipos. La finalidad de esta Tesis es establecer los requisitos que debe satisfacer una red para ser considerada Red Patrón con trazabilidad metrológica, así como la metodología para la verificación y calibración de instrumental GNSS en redes patrón. Para ello, se ha diseñado y elaborado un procedimiento técnico de calibración de equipos GNSS en el que se han definido las contribuciones a la incertidumbre de medida. El procedimiento, que se ha aplicado en diferentes redes para distintos equipos, ha permitido obtener la incertidumbre expandida de dichos equipos siguiendo las recomendaciones de la Guide to the Expression of Uncertainty in Measurement del Joint Committee for Guides in Metrology. Asimismo, se han determinado mediante técnicas de observación por satélite las coordenadas tridimensionales de las bases que conforman las redes consideradas en la investigación, y se han desarrollado simulaciones en función de diversos valores de las desviaciones típicas experimentales de los puntos fijos que se han utilizado en el ajuste mínimo cuadrático de los vectores o líneas base. Los resultados obtenidos han puesto de manifiesto la importancia que tiene el conocimiento de las desviaciones típicas experimentales en el cálculo de incertidumbres de las coordenadas tridimensionales de las bases. Basándose en estudios y observaciones de gran calidad técnica, llevados a cabo en estas redes con anterioridad, se ha realizado un exhaustivo análisis que ha permitido determinar las condiciones que debe satisfacer una red patrón. Además, se han diseñado procedimientos técnicos de calibración que permiten calcular la incertidumbre expandida de medida de los instrumentos geodésicos que proporcionan ángulos y distancias obtenidas por métodos electromagnéticos, ya que dichos instrumentos son los que van a permitir la diseminación de la trazabilidad metrológica a las redes patrón para la verificación y calibración de los equipos GNSS. De este modo, ha sido posible la determinación de las correcciones de calibración local de equipos GNSS de alta exactitud en las redes patrón. En esta Tesis se ha obtenido la incertidumbre de la corrección de calibración mediante dos metodologías diferentes; en la primera se ha aplicado la propagación de incertidumbres, mientras que en la segunda se ha aplicado el método de Monte Carlo de simulación de variables aleatorias. El análisis de los resultados obtenidos confirma la validez de ambas metodologías para la determinación de la incertidumbre de calibración de instrumental GNSS. ABSTRACT The studies carried out so far for the determination of the quality of measurement of geodetic instruments have been aimed, primarily, to measure angles and distances. However, in recent years it has been accepted to use GNSS (Global Navigation Satellite System) equipment in the field of Geomatic applications, for data capture, without establishing a methodology that allows obtaining the calibration correction and its uncertainty. The purpose of this Thesis is to establish the requirements that a network must meet to be considered a StandardNetwork with metrological traceability, as well as the methodology for the verification and calibration of GNSS instrumental in those standard networks. To do this, a technical calibration procedure has been designed, developed and defined for GNSS equipment determining the contributions to the uncertainty of measurement. The procedure, which has been applied in different networks for different equipment, has alloweddetermining the expanded uncertainty of such equipment following the recommendations of the Guide to the Expression of Uncertainty in Measurement of the Joint Committee for Guides in Metrology. In addition, the three-dimensional coordinates of the bases which constitute the networks considered in the investigationhave been determined by satellite-based techniques. There have been several developed simulations based on different values of experimental standard deviations of the fixed points that have been used in the least squares vectors or base lines calculations. The results have shown the importance that the knowledge of experimental standard deviations has in the calculation of uncertainties of the three-dimensional coordinates of the bases. Based on high technical quality studies and observations carried out in these networks previously, it has been possible to make an exhaustive analysis that has allowed determining the requirements that a standard network must meet. In addition, technical calibration procedures have been developed to allow the uncertainty estimation of measurement carried outby geodetic instruments that provide angles and distances obtained by electromagnetic methods. These instruments provide the metrological traceability to standard networks used for verification and calibration of GNSS equipment. As a result, it has been possible the estimation of local calibration corrections for high accuracy GNSS equipment in standardnetworks. In this Thesis, the uncertainty of calibration correction has been calculated using two different methodologies: the first one by applying the law of propagation of uncertainty, while the second has applied the propagation of distributions using the Monte Carlo method. The analysis of the obtained results confirms the validity of both methodologies for estimating the calibration uncertainty of GNSS equipment.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

A PIV-based system has been set-up for the simultaneous measurement of the local burning velocity of premixed flames and the flame stretch due to the flame front curvature and the incoming flow strain rate. For moderately short jet flames, these measurements allow an indirect determination of the Markstein length, according to Clavin and Joulin (C–J) theory. For tall flames, the flame curvature becomes relatively large in a region around the tip where the C–J theory breaks down. However, our experiments confirm the appearance of a new linear relation between burning velocity and curvature at the flame tip. This relation defines a new proportionality factor which is probably associated to the evolution from rounded tips to slender tips when the jet velocity is increased.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

This paper describes the design, development and field evaluation of a machine translation system from Spanish to Spanish Sign Language (LSE: Lengua de Signos Española). The developed system focuses on helping Deaf people when they want to renew their Driver’s License. The system is made up of a speech recognizer (for decoding the spoken utterance into a word sequence), a natural language translator (for converting a word sequence into a sequence of signs belonging to the sign language), and a 3D avatar animation module (for playing back the signs). For the natural language translator, three technological approaches have been implemented and evaluated: an example-based strategy, a rule-based translation method and a statistical translator. For the final version, the implemented language translator combines all the alternatives into a hierarchical structure. This paper includes a detailed description of the field evaluation. This evaluation was carried out in the Local Traffic Office in Toledo involving real government employees and Deaf people. The evaluation includes objective measurements from the system and subjective information from questionnaires. The paper details the main problems found and a discussion on how to solve them (some of them specific for LSE).

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Millennium Development Goals point out the necessity of actively promoting maternal-child health care status, especially in underserved areas. This article details the development actions carried out between 2008 and 2011 in some rural communities of Nicaragua with the aim to provide a low-cost tele-health communication service. The service is managed by the health care center of Cusmapa, which leads the program and maintains a communication link between its health staff and the health brigades of 26 distant communities. Local agents can use the system to report urgent maternal-child health care episodes to be assessed through WiMAX-WiFi voice and data communications attended by two physicians and six nurses located at the health care center. The health and nutritional status of the maternal-child population can be monitored to prevent diseases, subnutrition, and deaths. The action approach assumes the fundamentals of appropriate technology and looks for community- based, sustainable, replicable, and scalable solutions to ensure future deployments according to the strategies of the United Nations.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

The present investigation addresses the overall and local mechanical performance of dissimilar joints of low carbon steel (CS) and stainless steel (SS) thin sheets achieved by laser welding in case of heat source displacement from the weld gap centreline towards CS. Microstructure characterization and residua! strain scanning, carried out by neutron diffraction, were used to assess the joints features. It was found that the heat source position influences the base metals dilution and the residua! stress field associated to the welding process; the transverse residual stress is smaller than for the longitudinal component, of magnitudes close to the parent CS yield strength. Furthermore, compressive transverse residual stresses were encountered at the SS-weld interface. The tensile behavior of the joint different zones assessed by using a video-image based system (VIC-2D) reveals that the residual stress field, together with the positive difference in yield between the weld metal and the base materials protects the joint from being piastically deformed. The tensile loadings of flat transverse specimens generate the strain localization and failure in CS, far away from the weld.En este trabajo se exponen los resultados de una investigacion sobre el comportamiento mecanico de soldaduras disimiles acero inoxidable-acero al carbono, realizadas para unir chapas delgadas, desplazando la fuente de calor del eje longitudinal de la union soldada por laser sobre el acero al carbono. Se han determinado las caracteristicas microestructurales de la union soldada, las tensiones residuales generadas (mediante difraccion de neutrones) y las curvas tension-deformacion locales y globales, mediante medidas locales de deformacion empleando el sistema VIC-2D "video image correlation". El desplazamiento de la fuente de calor infiuye en la dilution de los metales base y el campo de tensiones residuales asociado al proceso de soldeo; las tensiones residuales medidas en direction longitudinal se aproximan al limite elastico del acero al carbono, mientras que las tensiones residuales transversales son menores, e incluso de compresion. El ensayo a traccion de la union soldada revela que las tensiones residuales y la diferencia de limite elastico entre los metales base y la soldadura propician que la rotura se produzca por inestabilidad plastica del acero al carbono, lejos de la soldadura, sin que la union plastifique.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

In this article, the authors examine the current status of different elements that integrate the landscape of the municipality of Olias del Rey in Toledo (Spain). A methodology for the study of rural roads, activity farming and local hunting management. We used Geographic Information Technologies (GIT) in order to optimize spatial information including the design of a Geographic Information System (GIS). In the acquisition of field data we have used vehicle "mobile mapping" instrumentation equipped with GNSS, LiDAR, digital cameras and odometer. The main objective is the integration of geoinformation and geovisualization of the information to provide a fundamental tool for rural planning and management.