Analysis of urban parameters in the characterization of seismic vulnerability: application to the city of Lorca.

Estimación de la intensidad tras el terremoto de Lorca.

Los pastos en las fincas de Lugar Nuevo y Selladores-Contadores (Sª de Andújar, Jaén): tipología, calidad y distribución espacial

Las fincas del O. A. Parques Nacionales “Lugar Nuevo” y “Selladores-Contadero” están situadas en el Parque Natural de la Sierra de Andújar (Jaén). Su situación geográfica, y especialmente su historia de usos y propiedad han motivado que hoy sean ejemplo de una flora y vegetación con buen estado de conservación. En trabajos anteriores se han realizado catálogos florísticos de las dos fincas como estudios básicos para la planificación de la gestión y la compatibilidad de la conservación y el aprovechamiento de los recursos en los espacios naturales protegidos. En esta comunicación se realiza un análisis de los pastos herbáceos de las dos fincas que constituyen un recurso estratégico para la alimentación de las poblaciones de herbívoros instaladas en las mismas. Se analizan y cartografían las distintas formaciones de pastos reconocidos (10), su distribución espacial, palatabilidad y grado de utilización

Coastal Urban Flood Resislience versus Climate Change

Processes of founding and expanding cities in coastal areas have undergone great changes over time driven by environmental conditions. Coastal settlements looked for places above flood levels and away from swamps and other wetlands whenever possible. As populations grew, cities were extending trying to avoid low and wet lands. No city has been able to limit its growth. The risk of flooding can never be eliminated, but only reduced to the extent possible. Flooding of coastal areas is today dramatically attributed to eustasic sea level rise caused by global climate change. This can be inaccurate. Current climate change is generating an average sea level upward trend, but other regional and local factors result in this trend being accentuated in some places or attenuated, and even reversed, in others. Then, the intensity and frequency of coastal flooding around the planet, although not so much as a unique result of this general eustasic elevation, but rather of the superposition of marine and crustal dynamic elements, the former also climate-related, which give rise to a temporary raising in average sea level in the short term. Since the Little Ice Age the planet has been suffering a global warming change leading to sea level rise. The idea of being too obeying to anthropogenic factors may be attributed to Arrhenius (1896), though it is of much later highlight after the sixties of the last century. Never before, the human factor had been able of such an influence on climate. However, other types of changes in sea levels became apparent, resulting from vertical movements of the crust, modifications of sea basins due to continents fracturing, drifting and coming together, or to different types of climate patterns. Coastal zones are then doubly susceptible to floods. Precipitation immediately triggers pluvial flooding. If it continues upland or when snow and glaciers melt eventually fluvial flooding can occur. The urban development presence represents modifying factors. Additional interference is caused by river and waste water drainage systems. Climate also influences sea levels in coastal areas, where tides as well as the structure and dynamic of the geoid and its crust come into play. From the sea, waters can flood and break or push back berms and other coastline borders. The sea level, controlling the mouth of the main channel of the basin's drainage system, is ultimately what governs flood levels. A temporary rise in sea level acts as a dam at the mouth. Even in absence of that global change, so, floods are likely going to increase in many urban coastal areas. Some kind of innovative methodologies and practices should be needed to get more flood resilience cities

Potential to attract drivers out of their cars in dense urban areas.

Purpose Sustainable mobility urban policies intend reducing car use and increasing walking, cycling and public transport. However, this transfer from private car to these more sustainable modes is only a real alternative where distances are small and the public transport supply competitive enough. This paper proposes a methodology to calculate the number of trips that can be transferred from private car to other modes in city centres. Method The method starts analyzing which kind of trips cannot change its mode (purposes, conditions, safety , etc.), and then setting a process to determine under which conditions trips made by car between given O-D pairs can be transferable. Then, the application of demand models allow to determine which trips fulfil the transferability conditions. The process test the possibility of transfer in a sequential way: firs to walking, then cycling and finally to public transport. Results The methodology is tested through its application to the city of Madrid (Spain), with the result of only some 18% of the trips currently made by car could be made by other modes, under the same conditions of trip time, and without affecting their characteristics. Out of these trips, 75% could be made by public transport, 15% cycling and 10% on foot. The possible mode to be transferred depends on the location: city centre areas are more favourable for walking and cycling while city skirts could attract more PT trips. Conclusions The proposed method has demonstrated its validity to determine the potential of transferring trips out of cars to more sustainable modes. Al the same time it is clear that, even in areas with favourable conditions for walking, cycling and PT trips, the potential of transfer is limited because cars fulfil more properly special requirements of some trips and tours.

Urban Coastal Flooding and Climate Change

Dentro del marco del Proyecto Europeo Smartest se presenta la publicación de las inundaciones en ciudades próximas a la costa y la influencia del cambio climático en la interface fluvio - marina con las condiciones ambientales que afectan al comportamiento evolutivo de la ciudad

A Visual AGV-Urban Car using Fuzzy Control

The goal of the work described in this paper is to develop a visual line guided system for being used on-board an Autonomous Guided Vehicle (AGV) commercial car, controlling the steering and using just the visual information of a line painted below the car. In order to implement the control of the vehicle, a Fuzzy Logic controller has been implemented, that has to be robust against curvature changes and velocity changes. The only input information for the controller is the visual distance from the image center captured by a camera pointing downwards to the guiding line on the road, at a commercial frequency of 30Hz. The good performance of the controller has successfully been demonstrated in a real environment at urban velocities. The presented results demonstrate the capability of the Fuzzy controller to follow a circuit in urban environments without previous information about the path or any other information from additional sensors

Multipath Reflectivity Estimation in Urban Environments for Synthetic Aperture Radar Images

Synthetic Aperture Radar (SAR) images a target region reflectivity function in the multi-dimensional spatial domain of range and cross-range. SAR synthesizes a large aperture radar in order to achieve a finer azimuth resolution than the one provided by any on-board real antenna. Conventional SAR techniques assume a single reflection of transmitted waveforms from targets. Nevertheless, today¿s new scenes force SAR systems to work in urban environments. Consequently, multiple-bounce returns are added to directscatter echoes. We refer to these as ghost images, since they obscure true target image and lead to poor resolution. By analyzing the quadratic phase error (QPE), this paper demonstrates that Earth¿s curvature influences the defocusing degree of multipath returns. In addition to the QPE, other parameters such as integrated sidelobe ratio (ISLR), peak sidelobe ratio (PSLR), contrast (C) and entropy (E) provide us with the tools to identify direct-scatter echoes in images containing undesired returns coming from multipath.

New Technique for Static Target Detection in Dense-Multipath Urban Environments

Synthetic Aperture Radar (SAR) images a target region reflectivity function in the multi-dimensional spatial domain of range and cross-range with a finer azimuth resolution than the one provided by any on-board real antenna. Conventional SAR techniques assume a single reflection of transmitted waveforms from targets. Nevertheless, new uses of Unmanned Aerial Vehicles (UAVs) for civilian-security applications force SAR systems to work in much more complex scenes such as urban environments. Consequently, multiple-bounce returns are additionally superposed to direct-scatter echoes. They are known as ghost images, since they obscure true target image and lead to poor resolution. All this may involve a significant problem in applications related to surveillance and security. In this work, an innovative multipath mitigation technique is presented in which Time Reversal (TR) concept is applied to SAR images when the target is concealed in clutter, leading to TR-SAR technique. This way, the effect of multipath is considerably reduced ?or even removed?, recovering the lost resolution due to multipath propagation. Furthermore, some focusing indicators such as entropy (E), contrast (C) and Rényi entropy (RE) provide us with a good focusing criterion when using TR-SAR.

A review of the distribution of particulate trace elements in urban terrestrial environments and its application to considerations of risk

We review the evolution, state of the art and future lines of research on the sources, transport pathways, and sinks of particulate trace elements in urban terrestrial environments to include the atmosphere, soils, and street and indoor dusts. Such studies reveal reductions in the emissions of some elements of historical concern such as Pb, with interest consequently focusing on other toxic trace elements such as As, Cd, Hg, Zn, and Cu. While establishment of levels of these elements is important in assessing the potential impacts of human society on the urban environment, it is also necessary to apply this knowledge in conjunction with information on the toxicity of those trace elements and the degree of exposure of human receptors to an assessment of whether such contamination represents a real risk to the city’s inhabitants and therefore how this risk can be addressed.

Geochemistry and risk assessment of street dust in Luanda, Angola, a tropical urban environment

A total of 92 samples of street dust were collected in Luanda, Angola, were sieved below 100 μm, and analysed by ICP-MS for 35 elements after an aqua-regia digestion. The concentration and spatial heterogeneity of trace elements in the street dust of Luanda are generally lower than in most industrialized cities in the Northern hemisphere. These observations reveal a predominantly “natural” origin for the street dust in Luanda, which is also manifested in that some geochemical processes that occur in natural soils are preserved in street dust: the separation of uranium from thorium, and the retention of the former by carbonate materials, or the high correlation between arsenic and vanadium due to their common mode of adsorption on solid particles in the form of oxyanions. The only distinct anthropogenic fingerprint in the composition of Luanda's street dust is the association Pb–Cd–Sb–Cu (and to a lesser extent, Ba–Cr–Zn). The use of risk assessment strategies has proved helpful in identifying the routes of exposure to street dust and the trace elements therein of most concern in terms of potential adverse health effects. In Luanda the highest levels of risk seem to be associated (a) with the presence of As and Pb in the street dust and (b) with the route of ingestion of dust particles, for all the elements included in the study except Hg, for which inhalation of vapours presents a slightly higher risk than ingestion. However, given the large uncertainties associated with the estimates of toxicity values and exposure factors, and the absence of site-specific biometric factors, these results should be regarded as preliminary and further research should be undertaken before any definite conclusions regarding potential health effects are drawn.

Geochemical fingerprints and controls in the sediments of an urban river: River Manzanares, Madrid (Spain)

The geochemical fingerprint of sediment retrieved from the banks of the River Manzanares as it passes through the City of Madrid is presented here. The river collects the effluent water from several Waste Water Treatment (WWT) plants in and around the city, such that, at low flows, up to 60% of the flow has been treated. A total of 18 bank-sediment cores were collected along the course of the river, down to its confluence with the Jarama river, to the south–east of Madrid. Trace and major elements in each sample were extracted following a double protocol: (a) “Total” digestion with HNO3, HClO4 and HF; (b) “Weak” digestion with sodium acetate buffered to pH=5 with acetic acid, under constant stirring. The digests thus obtained were subsequently analysed by ICP-AES, except for Hg which was extracted with aqua regia and sodium chloride-hydroxylamine sulfate, and analysed by Cold Vapour-AAS. X-ray diffraction was additionally employed to determine the mineralogical composition of the samples. Uni- and multivariate analyses of the chemical data reveal the influence of Madrid on the geochemistry of Manzanares' sediments, clearly manifested by a marked increase in the concentration of typically “urban” elements Ag, Cr, Cu, Pb and Zn, downstream of the intersection of the river with the city's perimeter. The highest concentrations of these elements appear to be associated with illegal or accidental dumping of waste materials, and with the uncontrolled incorporation of untreated urban runoff to the river. The natural matrix of the sediment is characterised by fairly constant concentrations of Ce, La and Y, whereas changes in the lithology intersected by the river cause corresponding variations in Ca–Mg and Al–Na contents. In the final stretch of the river, the presence of carbonate materials seems to exert a strong geochemical control on the amount of Zn and, to a lesser extent, Cu immobilised in the sediments. This fact suggests that a variable but significant proportion of both elements may be susceptible to reincorporation in the aqueous phase under realistic environmental conditions.

Optimization of urban mobility measures to achieve win-win strategies

European cities are essential in the development of Europe as they constitute the living environment of more than 60% of the population in the European Union and are drivers of the European economy – just under 85% of the EU’s gross domestic product is produced in urban areas (EC, 2007a). The car has been one of the main factors of development during the 20th century, but it is at the same time the origin of the key problems cities have to face: traffic increase. This has resulted in chronic congestion with many adverse consequences such as air pollution and noise. This loss of environmental quality is one of the reasons for urban sprawl in European cities during recent decades. But this urban sprawl at the same time worsens the environmental conditions. We must return to the dense city, but clean and competitive, and this implies reducing car use yet provides quality transport alternatives sufficient to recover and maintain the competitiveness of cities (EC, 2007a). Consequently, European cities need to establish an urban transport strategy which helps reduce their environmental problems –mainly emissions and noise – but without decreasing their trip attraction. This aspect is very important because a loss of trip attraction would result in an increase of people moving to more disperse areas, contributing towards worsening the current situation. This thesis is an attempt to contribute solutions to this problem in two ways: 1) The first is to analyze the complementarity and possible synergies of several urban transport measures aimed at improving a modal split to a more sustainable means of transport. This analysis will focus on the three aspects already mentioned: emissions, noise and attractiveness or competitiveness. 2) Once possible synergies and complementarities have been analyzed, the second objective is to propose the best combination of these measures, in terms of level of implementation, to achieve the maximum benefit with respect to the three aspects previously established: emissions, noise and attractiveness or competitiveness. Therefore, within the wide range of measures enhancing sustainable urban transport, three of them have been be selected in this thesis to establish a methodology for achieving these objectives. The analysis will be based on the region of Madrid, which is also the case study selected for this research. Las ciudades europeas son piezas fundamentales para el desarrollo europeo, ya que son el lugar de residencia de más del 60% de la población de la unión europea así como los motores de su economía – casi el 85% del PIB europeo se produce en áreas urbanas (EC, 2007a). El coche ha sido uno de los principales motores de desarrollo de las ciudades durante el siglo XX, pero se ha terminado por convertir a su vez en uno de los principales problemas con los que tiene que lidiar las ciudades: el aumento del tráfico. Esto ha derivado en unos niveles crónicos de congestión, con multitud de efectos adversos, entre los que cabe destacar la contaminación del aire y el ruido. Esta pérdida de calidad ambiental es una de las razones que ha propiciado la dispersión urbana que han experimentado las ciudades europeas en las últimas décadas. Pero esta dispersión urbana a su vez contribuye a empeorar las condiciones ambientales de las ciudades. Debemos retornar a la ciudad densa, pero limpia y competitiva, y esto implica reducir el uso del coche, pero proporcionando alternativas de transporte que permitan recuperar y mantener la competitividad de las ciudades (EC, 2007a). Por lo tanto, las ciudades europeas necesitan encontrar una estrategia de transporte urbano que ayude a reducir sus problemas medio ambientales – principalmente ruido y emisiones – pero sin hacerlas perder atractividad o competitividad. Este aspecto tiene gran importancia porque una pérdida de la misma se traduciría en un aumento de dispersión de la población hacia áreas periféricas, contribuyendo a empeorar la situación actual. Esta tesis contribuye a solucionar este problema de dos maneras: 1) La primera, analizando la complementariedad y posibles sinergias de diferentes medidas de transporte urbano orientadas a promover un reparto modal hacia modos más sostenibles. Este análisis se centrará en los tres aspectos anteriormente citados: emisiones, ruido y atractividad o competitividad. 2) Una vez las posibles sinergias y complementariedades se han analizado, el segundo objetivo es proponer la mejor combinación de estas medidas – en términos de grado de aplicación - para lograr el máximo beneficio en lo que respecta a los tres objetivos previamente establecidos. Para ello, en esta tesis se han seleccionado una serie de medidas que permitan establecer una metodología para alcanzar estos objetivos previamente definidos. El análisis se centra en la ciudad de Madrid y su área metropolitana, la cual se ha escogido como caso de estudio para realizar esta investigación.

Nueva terminal de pasajeros para el aeropuerto Federico García Lorca, Granada - Jaén

El presente proyecto de construcción define las actuaciones para la ejecución de la Nueva Terminal de pasajeros para el aeropuerto Federico García Lorca, Granada – Jaén, situado entre los términos municipales de Chauchina y Santa Fe, en la provincia de Granada. Estudios realizados por AENA, en colaboración con el Ministerio de Fomento, dejan constancia de los déficits en cuanto a capacidad de las instalaciones del aeropuerto se refiere, en múltiples facetas. En el caso de la terminal de pasajeros, sus principales elementos de servicio han sido sometidos a estudio, revelando claras faltas en numerosos puntos. El más relevante son las carencias en cuanto a capacidad, respecto a la demanda existente, y especialmente la demanda prevista para un cierto horizonte de estudio. Además, las nuevas normativas de aplicación en aeropuertos internacionales publicadas por la International Air Transport Association (IATA) entran en conflicto con ciertos parámetros de diseño de las instalaciones actuales. Se requiere una remodelación del conjunto para adaptarse a estas exigencias de validez internacional.

Efficiency and spatial equity impacts of high-speed rail extensions in urban areas

Urban areas benefit from significant improvements in accessibility when a new high speed rail (HSR) project is built. These improvements, which are due mainly to a rise in efficiency, produce locational advantagesand increase the attractiveness of these cities, thereby possibly enhancing their competitivenessand economic growth. However, there may be equity issues at stake, as the main accessibility benefits are primarily concentrated in urban areas with a HSR station, whereas other locations obtain only limited benefits. HSR extensions may contribute to an increase in spatial imbalance and lead to more polarized patterns of spatial development. Procedures for assessing the spatial impacts of HSR must therefore follow a twofold approach which addresses issues of both efficiency and equity. This analysis can be made by jointly assessing both the magnitude and distribution of the accessibility improvements deriving from a HSR project. This paper describes an assessment methodology for HSR projects which follows this twofold approach. The procedure uses spatial impact analysis techniques and is based on the computation of accessibility indicators, supported by a Geographical Information System (GIS). Efficiency impacts are assessed in terms of the improvements in accessibility resulting from the HSR project, with a focus on major urban areas; and spatial equity implications are derived from changes in the distribution of accessibility values among these urban agglomerations.

Sources and pathways of trace elements in urban environments: A multielemental qualitative approach

A geochemical model of an urban environment is presented in which multielemental tracers are used to characterise the circulation of trace elements in particulate matter_atmospheric aerosol, street dust and urban soil, within a city.