758 resultados para Fringe parking
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In this study, the work and life of Indian IT engineers in Japan engaged in software development were examined through a questionnaire survey. Findings were further supported by comparative analyses with Chinese and Korean software engineers. While Indian IT software engineers appeared rather satisfied with their life overall in Japan, they seemed rather dissatisfied with their work conditions including such things as fringe benefits, the working-time management of the company, levels of salary and bonuses, and promotion opportunities. It was made clear that profiles and perceptions of Indian engineers and those of Chinese and Koreans in Japan were different.
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La relación entre la estructura urbana y la movilidad ha sido estudiada desde hace más de 70 años. El entorno urbano incluye múltiples dimensiones como por ejemplo: la estructura urbana, los usos de suelo, la distribución de instalaciones diversas (comercios, escuelas y zonas de restauración, parking, etc.). Al realizar una revisión de la literatura existente en este contexto, se encuentran distintos análisis, metodologías, escalas geográficas y dimensiones, tanto de la movilidad como de la estructura urbana. En este sentido, se trata de una relación muy estudiada pero muy compleja, sobre la que no existe hasta el momento un consenso sobre qué dimensión del entorno urbano influye sobre qué dimensión de la movilidad, y cuál es la manera apropiada de representar esta relación. Con el propósito de contestar estas preguntas investigación, la presente tesis tiene los siguientes objetivos generales: (1) Contribuir al mejor entendimiento de la compleja relación estructura urbana y movilidad. y (2) Entender el rol de los atributos latentes en la relación entorno urbano y movilidad. El objetivo específico de la tesis es analizar la influencia del entorno urbano sobre dos dimensiones de la movilidad: número de viajes y tipo de tour. Vista la complejidad de la relación entorno urbano y movilidad, se pretende contribuir al mejor entendimiento de la relación a través de la utilización de 3 escalas geográficas de las variables y del análisis de la influencia de efectos inobservados en la movilidad. Para el análisis se utiliza una base de datos conformada por tres tipos de datos: (1) Una encuesta de movilidad realizada durante los años 2006 y 2007. Se obtuvo un total de 943 encuestas, en 3 barrios de Madrid: Chamberí, Pozuelo y Algete. (2) Información municipal del Instituto Nacional de Estadística: dicha información se encuentra enlazada con los orígenes y destinos de los viajes recogidos en la encuesta. Y (3) Información georeferenciada en Arc-GIS de los hogares participantes en la encuesta: la base de datos contiene información respecto a la estructura de las calles, localización de escuelas, parking, centros médicos y lugares de restauración. Se analizó la correlación entre e intra-grupos y se modelizaron 4 casos de atributos bajo la estructura ordinal logit. Posteriormente se evalúa la auto-selección a través de la estimación conjunta de las elecciones de tipo de barrio y número de viajes. La elección del tipo de barrio consta de 3 alternativas: CBD, Urban y Suburban, según la zona de residencia recogida en las encuestas. Mientras que la elección del número de viajes consta de 4 categorías ordinales: 0 viajes, 1-2 viajes, 3-4 viajes y 5 o más viajes. A partir de la mejor especificación del modelo ordinal logit. Se desarrolló un modelo joint mixed-ordinal conjunto. Los resultados indican que las variables exógenas requieren un análisis exhaustivo de correlaciones con el fin de evitar resultados sesgados. ha determinado que es importante medir los atributos del BE donde se realiza el viaje, pero también la información municipal es muy explicativa de la movilidad individual. Por tanto, la percepción de las zonas de destino a nivel municipal es considerada importante. En el contexto de la Auto-selección (self-selection) es importante modelizar conjuntamente las decisiones. La Auto-selección existe, puesto que los parámetros estimados conjuntamente son significativos. Sin embargo, sólo ciertos atributos del entorno urbano son igualmente importantes sobre la elección de la zona de residencia y frecuencia de viajes. Para analizar la Propensión al Viaje, se desarrolló un modelo híbrido, formado por: una variable latente, un indicador y un modelo de elección discreta. La variable latente se denomina “Propensión al Viaje”, cuyo indicador en ecuación de medida es el número de viajes; la elección discreta es el tipo de tour. El modelo de elección consiste en 5 alternativas, según la jerarquía de actividades establecida en la tesis: HOME, no realiza viajes durante el día de estudio, HWH tour cuya actividad principal es el trabajo o estudios, y no se realizan paradas intermedias; HWHs tour si el individuo reaiza paradas intermedias; HOH tour cuya actividad principal es distinta a trabajo y estudios, y no se realizan paradas intermedias; HOHs donde se realizan paradas intermedias. Para llegar a la mejor especificación del modelo, se realizó un trabajo importante considerando diferentes estructuras de modelos y tres tipos de estimaciones. De tal manera, se obtuvieron parámetros consistentes y eficientes. Los resultados muestran que la modelización de los tours, representa una ventaja sobre la modelización de los viajes, puesto que supera las limitaciones de espacio y tiempo, enlazando los viajes realizados por la misma persona en el día de estudio. La propensión al viaje (PT) existe y es específica para cada tipo de tour. Los parámetros estimados en el modelo híbrido resultaron significativos y distintos para cada alternativa de tipo de tour. Por último, en la tesis se verifica que los modelos híbridos representan una mejora sobre los modelos tradicionales de elección discreta, dando como resultado parámetros consistentes y más robustos. En cuanto a políticas de transporte, se ha demostrado que los atributos del entorno urbano son más importantes que los LOS (Level of Service) en la generación de tours multi-etapas. la presente tesis representa el primer análisis empírico de la relación entre los tipos de tours y la propensión al viaje. El concepto Propensity to Travel ha sido desarrollado exclusivamente para la tesis. Igualmente, el desarrollo de un modelo conjunto RC-Number of trips basado en tres escalas de medida representa innovación en cuanto a la comparación de las escalas geográficas, que no había sido hecha en la modelización de la self-selection. The relationship between built environment (BE) and travel behaviour (TB) has been studied in a number of cases, using several methods - aggregate and disaggregate approaches - and different focuses – trip frequency, automobile use, and vehicle miles travelled and so on. Definitely, travel is generated by the need to undertake activities and obtain services, and there is a general consensus that urban components affect TB. However researches are still needed to better understand which components of the travel behaviour are affected most and by which of the urban components. In order to fill the gap in the research, the present dissertation faced two main objectives: (1) To contribute to the better understanding of the relationship between travel demand and urban environment. And (2) To develop an econometric model for estimating travel demand with urban environment attributes. With this purpose, the present thesis faced an exhaustive research and computation of land-use variables in order to find the best representation of BE for modelling trip frequency. In particular two empirical analyses are carried out: 1. Estimation of three dimensions of travel demand using dimensions of urban environment. We compare different travel dimensions and geographical scales, and we measure self-selection contribution following the joint models. 2. Develop a hybrid model, integrated latent variable and discrete choice model. The implementation of hybrid models is new in the analysis of land-use and travel behaviour. BE and TB explicitly interact and allow richness information about a specific individual decision process For all empirical analysis is used a data-base from a survey conducted in 2006 and 2007 in Madrid. Spatial attributes describing neighbourhood environment are derived from different data sources: National Institute of Statistics-INE (Administrative: municipality and district) and GIS (circular units). INE provides raw data for such spatial units as: municipality and district. The construction of census units is trivial as the census bureau provides tables that readily define districts and municipalities. The construction of circular units requires us to determine the radius and associate the spatial information to our households. The first empirical part analyzes trip frequency by applying an ordered logit model. In this part is studied the effect of socio-economic, transport and land use characteristics on two travel dimensions: trip frequency and type of tour. In particular the land use is defined in terms of type of neighbourhoods and types of dwellers. Three neighbourhood representations are explored, and described three for constructing neighbourhood attributes. In particular administrative units are examined to represent neighbourhood and circular – unit representation. Ordered logit models are applied, while ordinal logit models are well-known, an intensive work for constructing a spatial attributes was carried out. On the other hand, the second empirical analysis consists of the development of an innovative econometric model that considers a latent variable called “propensity to travel”, and choice model is the choice of type of tour. The first two specifications of ordinal models help to estimate this latent variable. The latent variable is unobserved but the manifestation is called “indicators”, then the probability of choosing an alternative of tour is conditional to the probability of latent variable and type of tour. Since latent variable is unknown we fit the integral over its distribution. Four “sets of best variables” are specified, following the specification obtained from the correlation analysis. The results evidence that the relative importance of SE variables versus BE variables depends on how BE variables are measured. We found that each of these three spatial scales has its intangible qualities and drawbacks. Spatial scales play an important role on predicting travel demand due to the variability in measures at trip origin/destinations within the same administrative unit (municipality, district and so on). Larger units will produce less variation in data; but it does not affect certain variables, such as public transport supply, that are more significant at municipality level. By contrast, land-use measures are more efficient at district level. Self-selection in this context, is weak. Thus, the influence of BE attributes is true. The results of the hybrid model show that unobserved factors affect the choice of tour complexity. The latent variable used in this model is propensity to travel that is explained by socioeconomic aspects and neighbourhood attributes. The results show that neighbourhood attributes have indeed a significant impact on the choice of the type of tours either directly and through the propensity to travel. The propensity to travel has a different impact depending on the structure of each tour and increases the probability of choosing more complex tours, such as tours with many intermediate stops. The integration of choice and latent variable model shows that omitting important perception and attitudes leads to inconsistent estimates. The results also indicate that goodness of fit improves by adding the latent variable in both sequential and simultaneous estimation. There are significant differences in the sensitivity to the latent variable across alternatives. In general, as expected, the hybrid models show a major improvement into the goodness of fit of the model, compared to a classical discrete choice model that does not incorporate latent effects. The integrated model leads to a more detailed analysis of the behavioural process. Summarizing, the effect that built environment characteristics on trip frequency studied is deeply analyzed. In particular we tried to better understand how land use characteristics can be defined and measured and which of these measures do have really an impact on trip frequency. We also tried to test the superiority of HCM on this field. We can concluded that HCM shows a major improvement into the goodness of fit of the model, compared to classical discrete choice model that does not incorporate latent effects. And consequently, the application of HCM shows the importance of LV on the decision of tour complexity. People are more elastic to built environment attributes than level of services. Thus, policy implications must take place to develop more mixed areas, work-places in combination with commercial retails.
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Decreasing the accidents on highway and urban environments is the main motivation for the research and developing of driving assistance systems, also called ADAS (Advanced Driver Assistance Systems). In recent years, there are many applications of these systems in commercial vehicles: ABS systems, Cruise Control (CC), parking assistance and warning systems (including GPS), among others. However, the implementation of driving assistance systems on the steering wheel is more limited, because of their complexity and sensitivity. This paper is focused in the development, test and implementation of a driver assistance system for controlling the steering wheel in curve zones. This system is divided in two levels: an inner control loop which permits to execute the position and speed target, softening the action over the steering wheel, and a second control outer loop (controlling for fuzzy logic) that sends the reference to the inner loop according the environment and vehicle conditions. The tests have been done in different curves and speeds. The system has been proved in a commercial vehicle with satisfactory results.
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El proyecto tiene como objetivo realizar el diseño de la cimentación de Torre Reforma. Torre Reforma se ubica en Av. Paseo de la Reforma No. 483, en la esquina con Rio Elba, en la ciudad de México. Dicha ubicación geotécnicamente corresponde a lo que se conoce como la Zona de Lago. La superficie construida será de 2780 m2 y el edificio contará con una altura de 244 m y un total de 57 plantas. Por debajo del nivel de calle el edificio constará de 10 niveles de sótano destinados a aparcamiento. Partiendo de los parámetros geotécnicos del terreno, el proyecto consistirá en calcular una parte de la cimentación empleada en este edificio. Este proyecto se podrá utilizar como guía para realizar cimentaciones parecidas para otros edificios. ABSTRACT The objective of this Project is to make the design of the foundation of Torre Reforma. Torre Reforma is located in Av. Paseo de la Reforma No. 483, on the corner with Río Elba in México City. Geotechnically this location corresponds to what it is known as “la Zona del Lago” or Lake Zone. The constructed area is of 2780 m2 and the building will have a height of 244 m and a total of 57 floors. Below street level the building will include ten basement levels for parking. Based on the geotechnical parameters of the site, the project will consist in calculating a part of the foundation used in this building. This project will be able to be used as a guide for future projects of foundations of buildings in similar conditions.
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Travel time savings, better quality of the supplied services, greater comfort for the users, and improved accessibility are the main factors of success of High Speed Rail(HSR)links. This paper presents the results from a revealed and stated preference survey conducted to both HSR and air transport users in the Madrid Barcelona corridor. The data gathered from the stated preference survey was used to calibrate a modal choice model aiming at explaining competition between HSR and air transportation in the corridor. From the model, the authors obtain that prices and service frequency are the most important variables to compete with the other mode. In addition, they found that check-in and security controls at the airport are a crucial variable for the users in their modal choice. Other policies, such as the improvement of parking facilities at the train stations, play a secondary role.
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The commercial centre VIALIA and the new railway station of the AVE (high speed train) in Malaga was inaugurated in November 2006, just on the place of the former railway station. The new railway station with an investment of 134,7 million Euros occupies a surface of 51.377 m2, five times the surface of the former station. The enclosure is the biggest intermodal and commercial centre of Spain which comprises a parking of 21.000 m2 for 1300 parking places, one commercial area and a hotel with a total extension constructed of approximately 100.000 m2. The spaces of leisure contain cinemas, shops, restaurants, bowling, gymnasium, swimming pool and zones of passenger's traffic.
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Assessing users’ benefit in a transport policy implementation has been studied by many researchers using theoretical or empirical measures. However, few of them measure users’ benefit in a different way from the consumer surplus. Therefore, this paper aims to assess a new measure of user benefits by weighting consumer surplus in order to include equity assessment for different transport policies simulated in a dynamic middle-term LUTI model adapted to the case study of Madrid. Three different transport policies, including road pricing, parking charge and public transport improvement have been simulated through the Metropolitan Activity Relocation Simulator, MARS, the LUTI calibrated model for Madrid). A social welfare function (WF) is defined using a cost benefit analysis function that includes mainly costs and benefits of users and operators of the transport system. Particularly, the part of welfare function concerning the users, (i.e. consumer surplus), is modified by a compensating weight (CW) which represents the inverse of household income level. Based on the modified social welfare function, the effects on the measure of users benefits are estimated and compared with the old WF ́s results as well. The result of the analysis shows that road pricing leads a negative effect on the users benefits specially on the low income users. Actually, the road pricing and parking charge implementation results like a regressive policy especially at long term. Public transport improvement scenario brings more positive effects on low income user benefits. The integrated (road pricing and increasing public services) policy scenario is the one which receive the most user benefits. The results of this research could be a key issue to understanding the relationship between transport systems policies and user benefits distribution in a metropolitan context.
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The commercial centre VIALIA and the new railway station of the AVE (high speed train) in Malaga was inaugurated in November 2006, just on the place of the former railway station. The new railway station with an investment of 134,7 million Euros occupies a surface of 51.377 m2, five times the surface of the former station. The enclosure is the biggest intermodal and commercial centre of Spain which comprises a parking of 21.000 m2 for 1300 parking places, one commercial area and a hotel with a total extension constructed of approximately 100.000 m2. The spaces of leisure contain cinemas, shops, restaurants, bowling, gymnasium, swimming pool and zones of passenger's traffic.
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En las últimas décadas el mundo ha sufrido un aumento exponencial en la utilización de soluciones tecnológicas, lo que ha desembocado en la necesidad de medir situaciones o estados de los distintos objetos que nos rodean. A menudo, no es posible cablear determinados sensores por lo que ese aumento en la utilización de soluciones tecnológicas, se ha visto traducido en un aumento de la necesidad de utilización de sensórica sin cables para poder hacer telemetrías correctas. A nivel social, el aumento de la demografía mundial está estrechamente ligado al aumento de la necesidad de servicios tecnológicos, por lo que es lógico pensar que a más habitantes, más tecnología será consumida. El objetivo de este Proyecto Final de Carrera está basado en la utilización de diversos nodos o también llamados motas capaces de realizar transferencia de datos en modo sin cables, permitiendo así realizar una aplicación real que solvente problemas generados por el aumento de la densidad de población. En concreto se busca la realización de un sistema de aparcamiento inteligente para estacionamientos en superficie, ayudando por tanto a las tareas de ordenación vehicular dentro del marco de las Smart cities. El sistema está basado en el protocolo de comunicaciones 802.15.4 (ZigBee) cuyas características fundamentales radican en el bajo consumo de energía de los componentes hardware asociados. En primer lugar se realizará un Estado del Arte de las Redes Inalámbricas de Sensores, abordando tanto la arquitectura como el estándar Zigbee y finalmente los componentes XBee que se van a utilizar en este Proyecto. Seguidamente se realizará la algoritmia necesaria para el buen funcionamiento del sistema inteligente de estacionamiento y finalmente se realizará un piloto demostrador del correcto funcionamiento de la tecnología. ABSTRACT In the last decades the world has experienced an exponential increase in the use of technological solutions, which has resulted in the need to measure situations or states of the objects around us. Often, wired sensors cannot be used at many situations, so the increase in the use of technological solutions, has been translated into a increase of the need of using wireless sensors to make correct telemetries. At the social level, the increase in global demographics is closely linked to the increased need for technological services, so it is logical that more people, more technology will be consumed. The objective of this Final Project is based on the use of various nodes or so-called motes, capable of performing data transfer in wireless mode, thereby allowing performing a real application solving problems generated by the increase of population densities. Specifically looking for the realization of a smart outdoor parking system, thus helping to vehicular management tasks within the framework of the Smart Cities. The system is based on the communication protocol 802.15.4 (ZigBee) whose main characteristics lie in the low energy consumption associated to the hardware components. First there will be a State of the Art of Wireless Sensor Networks, addressing both architecture and finally the Zigbee standard XBee components to be used in this project. Then the necessary algorithms will be developed for the proper working of the intelligent parking system and finally there will be a pilot demonstrator validating the whole system.
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Hoy en día, el desarrollo tecnológico en el campo de los sistemas inteligentes de transporte (ITS por sus siglas en inglés) ha permitido dotar a los vehículos con diversos sistemas de ayuda a la conducción (ADAS, del inglés advanced driver assistance system), mejorando la experiencia y seguridad de los pasajeros, en especial del conductor. La mayor parte de estos sistemas están pensados para advertir al conductor sobre ciertas situaciones de riesgo, como la salida involuntaria del carril o la proximidad de obstáculos en el camino. No obstante, también podemos encontrar sistemas que van un paso más allá y son capaces de cooperar con el conductor en el control del vehículo o incluso relegarlos de algunas tareas tediosas. Es en este último grupo donde se encuentran los sistemas de control electrónico de estabilidad (ESP - Electronic Stability Program), el antibloqueo de frenos (ABS - Anti-lock Braking System), el control de crucero (CC - Cruise Control) y los más recientes sistemas de aparcamiento asistido. Continuando con esta línea de desarrollo, el paso siguiente consiste en la supresión del conductor humano, desarrollando sistemas que sean capaces de conducir un vehículo de forma autónoma y con un rendimiento superior al del conductor. En este trabajo se presenta, en primer lugar, una arquitectura de control para la automatización de vehículos. Esta se compone de distintos componentes de hardware y software, agrupados de acuerdo a su función principal. El diseño de la arquitectura parte del trabajo previo desarrollado por el Programa AUTOPIA, aunque introduce notables aportaciones en cuanto a la eficiencia, robustez y escalabilidad del sistema. Ahondando un poco más en detalle, debemos resaltar el desarrollo de un algoritmo de localización basado en enjambres de partículas. Este está planteado como un método de filtrado y fusión de la información obtenida a partir de los distintos sensores embarcados en el vehículo, entre los que encontramos un receptor GPS (Global Positioning System), unidades de medición inercial (IMU – Inertial Measurement Unit) e información tomada directamente de los sensores embarcados por el fabricante, como la velocidad de las ruedas y posición del volante. Gracias a este método se ha conseguido resolver el problema de la localización, indispensable para el desarrollo de sistemas de conducción autónoma. Continuando con el trabajo de investigación, se ha estudiado la viabilidad de la aplicación de técnicas de aprendizaje y adaptación al diseño de controladores para el vehículo. Como punto de partida se emplea el método de Q-learning para la generación de un controlador borroso lateral sin ningún tipo de conocimiento previo. Posteriormente se presenta un método de ajuste on-line para la adaptación del control longitudinal ante perturbaciones impredecibles del entorno, como lo son los cambios en la inclinación del camino, fricción de las ruedas o peso de los ocupantes. Para finalizar, se presentan los resultados obtenidos durante un experimento de conducción autónoma en carreteras reales, el cual se llevó a cabo en el mes de Junio de 2012 desde la población de San Lorenzo de El Escorial hasta las instalaciones del Centro de Automática y Robótica (CAR) en Arganda del Rey. El principal objetivo tras esta demostración fue validar el funcionamiento, robustez y capacidad de la arquitectura propuesta para afrontar el problema de la conducción autónoma, bajo condiciones mucho más reales a las que se pueden alcanzar en las instalaciones de prueba. ABSTRACT Nowadays, the technological advances in the Intelligent Transportation Systems (ITS) field have led the development of several driving assistance systems (ADAS). These solutions are designed to improve the experience and security of all the passengers, especially the driver. For most of these systems, the main goal is to warn drivers about unexpected circumstances leading to risk situations such as involuntary lane departure or proximity to other vehicles. However, other ADAS go a step further, being able to cooperate with the driver in the control of the vehicle, or even overriding it on some tasks. Examples of this kind of systems are the anti-lock braking system (ABS), cruise control (CC) and the recently commercialised assisted parking systems. Within this research line, the next step is the development of systems able to replace the human drivers, improving the control and therefore, the safety and reliability of the vehicles. First of all, this dissertation presents a control architecture design for autonomous driving. It is made up of several hardware and software components, grouped according to their main function. The design of this architecture is based on the previous works carried out by the AUTOPIA Program, although notable improvements have been made regarding the efficiency, robustness and scalability of the system. It is also remarkable the work made on the development of a location algorithm for vehicles. The proposal is based on the emulation of the behaviour of biological swarms and its performance is similar to the well-known particle filters. The developed method combines information obtained from different sensors, including GPS, inertial measurement unit (IMU), and data from the original vehicle’s sensors on-board. Through this filtering algorithm the localization problem is properly managed, which is critical for the development of autonomous driving systems. The work deals also with the fuzzy control tuning system, a very time consuming task when done manually. An analysis of learning and adaptation techniques for the development of different controllers has been made. First, the Q-learning –a reinforcement learning method– has been applied to the generation of a lateral fuzzy controller from scratch. Subsequently, the development of an adaptation method for longitudinal control is presented. With this proposal, a final cruise control controller is able to deal with unpredictable environment disturbances, such as road slope, wheel’s friction or even occupants’ weight. As a testbed for the system, an autonomous driving experiment on real roads is presented. This experiment was carried out on June 2012, driving from San Lorenzo de El Escorial up to the Center for Automation and Robotics (CAR) facilities in Arganda del Rey. The main goal of the demonstration was validating the performance, robustness and viability of the proposed architecture to deal with the problem of autonomous driving under more demanding conditions than those achieved on closed test tracks.
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La cuenca del Duero constituye un vasto territorio ibérico cuyo paisaje se encuentra actualmente muy alterado por la mano del hombre y es prácticamente imposible localizar alguna manifestación de su cubierta vegetal natural. Aunque la historia de la vegetación en los sectores central y oriental es relativamente bien conocida, en su mitad occidental los registros paleoecológicos estudiados hasta la fecha son prácticamente inexistentes. Esto hace que se desconozca la respuesta de la vegetación a las diferentes oscilaciones climáticas que se han producido desde el Último Máximo Glaciar, cuál fue el impacto de las diferentes culturas sobre el medio, cuándo se produjo una alteración profunda de la vegetación natural y cuál ha sido la historia de los incendios. Este último aspecto, el papel e importancia de los incendios, reviste un especial interés en la península Ibérica dada su situación geográfica y climática dentro de la cuenca Mediterránea, donde el fuego es un factor ecológico de primer nivel. Las distintas técnicas paleoecológicas son las más adecuadas para abordar todas estas preguntas. De este modo, los avatares de la vegetación a través del tiempo se han reconstruido mediante el análisis polínico y de macrofósiles, el impacto humano se ha trazado utilizando indicadores polínicos ligados a actividades antrópicas y esporas de hongos coprófilos, estudiándose los incendios a partir del registro de partículas microscópicas de carbón. La alta resolución temporal y taxonómica alcanzada en estos análisis, así como la amplia superficie abarcada con los yacimientos estudiados, hacen que la información obtenida sea altamente detallada y complete el conocimiento que se tiene sobre la cuenca del Duero. El Tardiglaciar se registra por primera vez en la Meseta Norte Ibérica en la secuencia de Ayoó de Vidriales, donde una vegetación esteparia prácticamente desarbolada domina durante los periodos fríos. Durante el interestadial Bølling/Allerød la expansión forestal (pinos, abedules) fue muy leve y tardía y fue interrumpida bruscamente por el Dryas Reciente. Al final del Dryas Reciente o al inicio del Holoceno se produjo una acusada y rápida expansión de los bosques. Esta dinámica sugiere que no hubo refugios glaciares importantes en esta zona de la Meseta durante el “Mystery Interval”, aparentemente el periodo más frío y seco. Los incendios fueron muy escasos, aumentando de forma muy brusca al inicio del Holoceno por el aumento de biomasa y las condiciones relativamente cálidas y secas. A partir de los registros de Ayoó y El Maíllo se consolida la importancia del gradiente oceanicidad-continentalidad en el Sistema Central y la Meseta Norte, que se manifiesta principalmente en la dominancia más prolongada de los pinares hacia el interior. Además, otra de las principales contribuciones de la presente tesis es proporcionar evidencia sobre la sucesión de distintos tipos de bosques en el noroeste de la Meseta, precisando el marco temporal en el que suceden. Así, se ha constatado que hubo un máximo desarrollo del bosque caducifolio durante el Holoceno medio en Ayoó de Vidriales y una baja incidencia del fuego que sugieren que el clima fue más húmedo que en el Holoceno inicial. El estudio de macrofósiles leñosos ha permitido detectar procesos que con el análisis polínico habrían pasado desapercibidos, como la persistencia hasta el Holoceno final de Pinus sylvestris en la sierra del Teleno y la sustitución de P. sylvestris por P. pinaster en la sierra de Francia durante el Holoceno inicial. También el estudio de los carbones procedentes de los arenales de Tierra de Pinares han proporcionado la prueba definitiva de la naturalidad de los pinares de P. pinaster. El impacto humano se detecta temprano en las secuencias del oeste de la cuenca del Duero, durante el Neolítico, aunque ha sido mucho más acusado desde la Edad del Hierro (ca 2700-2500 años cal BP). Para la detección del impacto humano temprano ha sido clave el análisis de esporas de hongos coprófilos, cuyo análisis fue incorporado en la secuencia de Ayoó de Vidriales. Una de sus principales consecuencias fue el establecimiento de comunidades de matorral (brezales, piornales) sobre amplias extensiones del occidente de la cuenca del Duero, vinculado al recrudecimiento de los regímenes de incendios. A pesar de que los incendios han sido ecológicamente importantes desde el inicio del Holoceno, los cambios introducidos por el hombre en sus regímenes sobrepasaron la resiliencia de los bosques originales, lo cual condujo a su sustitución sostenida por matorrales. ABSTRACT The Duero Basin constitutes a vast Iberian territory which is currently strongly disturbed due to human activities, so it is very difficult to find any remnant of the natural vegetation. Vegetation history for the eastern and western sectors of the Basin is relatively well-known but, in contrast, there is an almost complete lack of palaeoecological record in the western area. Consequently, there exists a profound ignorance about vegetation responses to the climatic oscillations occurred since the Last Glacial Maximum, the environmental impact of the different cultures, when a severe disturbance of the natural vegetation took place and fire history. The last question, the role and importance of fire, has a special interest in the Iberian Peninsula due to its geographic and climatic framework, the Mediterranean Basin, where fire is a major ecological factor. The diverse palaeoecological techmiques are the most suitable tools to address all these questions. Thus, vegetation shifts through time have been reconstructed using pollen and macrofossil analyses, human impact has been tracked by means of anthropogenic pollen indicators and dung fungal spores, while fire history has been studied from the quantification of microscopic charcoal particles. The high taxonomic and time resolution attained along with the extensive surface covered by the studied sites provide detailed information very useful to complete the knowledge on landscape dynamics in the Duero Basin. The Lateglacial is recorded for the first time in the Northern Iberian Plateau in the sequence from Ayoó de Vidriales, showing that almost treeless steppic vegetation dominated during the cold periods. Tree expansion (pines, birches) was late and slight during the Bølling/Allerød interstadial and was sharply interrupted by the Younger Dryas (YD) climatic reversal. By the end of the YD or the onset of the Holocene, a rapid forest expansion occurred. This forest dynamics suggests an absence of important glacial refugia for trees in this area of the Plateau during the Mystery Interval, apparently the coldest and driest period. Fires were fairly rare, increasing abruptly at the beginning of the Holocene due to the relatively warm and dry climate and the accumulation of biomass. The records from Ayoó and El Maíllo reinforce the role of the oceanicity-continentality gradient in the vegetation history of the Iberian Central Range and the Iberian Northern Plateau, reflected mainly in the longer dominance of pine forests towards inland areas. Further, another important contribution of this PhD Thesis is providing evidence on the succession of different forest types in the northestern fringe of the Plateau, specifying the chronological framework. A maximum of deciduous forest development and low fire activity have been detected in Ayoó de Vidriales during the mid-Holocene, suggesting that climate was wetter than in the early Holocene. The study of woody macrofossils has allowed detecting processes which would have remained unnoticed using pollen analysis alone, such as the persistence of Pinus sylvestris until the late Holocene in the Teleno Mountains and the early Holocene replacement of P. sylvestris with P. pinaster in the sierra de Francia range. The study of macroscopic charcoal fragments from palaeosols of the Tierra de Pinares has also provided the definitive proof of naturalness for the P. pinaster stands gorwing over this area at present. Early human impact, during the Neolithic, has been detected in the sequences from the western sector of the Duero Basin, although human disturbance has been more severe from the Iron Age onwards (ca 2700-2500 cal yr BP). The analysis of coprophilous fungi incorporated in the sequence of Ayoó de Vidriales has played a key role in recognizing that early human impact. One of the main consequences of human disturbance was the establishment of shrubland communities (heaths, brooms) over huge areas of the western Duero Basin, linked to severe and/or frequent fires. Despite fires has been ecologically important since the onset of the Holocene, human-induced changes in fire regimes have exceeded the resilience of original forests leading to a sustained replacement with shrublands.
Resumo:
The new railway station of María Zambrano for AVE (Spanish high-speed trains) located in Malaga, has been inaugurated in November 2006, just on the site of the former railway station. The new railway station with an investment of 134.7 million Euros occupies a surface of 51.377 m2, five times the surface of the former station. The enclosure is the biggest intermodal transport and commercial center of Spain which comprises a parking of 21,000 m2 for 1,300 parking places, one commercial area and a hotel of 35 m height, with a total extension constructed of approximately 100,000 m2.
Resumo:
According to UN provisions in the period from 2007 to 2050 world population will grow up to 9200 million people. In fact, for the first time in history, in the year 2008 world urban population became higher than rural population. The increase of urban areas and their transport infrastructures has influenced agricultural land use due to their irreversible change, especially when they remain as periurban vacant land, losing their character and identity. In the Europe of the nineties, the traditional urban-rural gradient, characterized by a neat contact between both land types, has become so complex that it has change to a gradient in which it is difficult to separate urban and rural land uses. [Antrop 2004]. A literature review has been made on methodologies used for the urban-rural gradient analysis. One of these methodologies was selected that integrates ecological characterization based on the use of spatial metrics and geographical characterization based on spatial components. Cartographical sources used were Corine Land Cover at 1: 100000 scale and the Spanish Land Use Information System at 1:25000 scale. Urban-rural gradient paradigm is an analysis methodology, coming from landscape ecology, which enables to investigate how urbanization provokes changes in ecological patterns and processes into landscape. [Hahs and McDonnell 2006].The present research adapt this methodology to study the urban-rural gradient in the outskirts of Madrid, Toledo and Guadalajara. Both scales (1:25000 and 1:100000) were simultaneously used to reach the next objectives: 1) Analysis of landscape pattern dynamics in relation to distance to the town centre and major infrastructures. 2) Analysis of landscape pattern dynamics in the fringe of protected areas. The paper presents a new approach to the urban-rural relationship which allows better planning and management of urban áreas.
Resumo:
El presente proyecto tiene como objetivo principal el análisis de la viabilidad de estacionamiento de vehículos propulsados por gas natural comprimido (GNC) desde el punto de vista de formación de atmosferas potencialmente explosivas en los garajes subterráneos. Además se ha realizado una breve introducción sobre el GNC explicando el origen, la composición y los diferentes usos que tiene. Se ha realizado la evaluación de riesgos asociados a la utilización de vehículos propulsados por gas natural y estimación de tasas de escape en el circuito de combustible de los vehículos propulsados por GNC. Para ello se ha aplicado la normativa UNE EN 60079-10 traspuesta en España mediante el Real Decreto del 681/2003 sobre la salud y la seguridad de los trabajadores y el Real Decreto 400/1996 sobre aparatos y sistemas de protección para su uso en atmósferas explosivas. Finalmente se han expuesto las medidas de prevención y protección necesarias para prevenir la generación de atmosferas potencialmente explosivas en los garajes subterráneos y se han detallado los procedimientos y las operaciones que han de realizarse. En las conclusiones se han explicado las acciones más importantes que deben emprenderse para mejorar la seguridad de personas e instalaciones en las áreas de riesgo por presencia de atmósferas potencialmente explosivas. ABSTRACT The main objective of this project is to analyze the viability of the parking of vehicles powered by compressed natural gas (CNG) in the underground garages from the point of view of generated of potentially explosive atmospheres in garages. A brief introduction about the CNG explaining the origin, composition and the different uses that it has is also included. An assessment of the risks associated with the use of vehicles powered by natural gas has been provided as well as an estimate of the exhaust rates on the gas circuit of CNG vehicles. In order to do that, the standard UNE EN 60079-10 transposed in Spain by the Royal Decree 681/2003 about the health and safety of workers and the Royal Decree 400/1996 about equipment and protection systems to be used in explosive atmospheres have been applied. Finally, the necessary preventive and protective measures to prevent the generation of potentially explosive atmospheres in underground garages have been presented and the procedures and operations to be performed have been detailed. In the conclusions, the most important actions to be taken in order to improve the safety of people and facilities in the areas at risk of having potentially explosive atmospheres have been described.