986 resultados para Environmental Impacts


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Internet fue sólo el principio de los grandes cambios. Desde la invención de la imprenta no ha habido un cambio tecnológico con tantas repercusiones como el de la era de la digitalización. Más aún, con la aparición de los primeros terminales móviles que confirmaron la nueva revolución en esta etapa. Este proyecto se centra en el caso europeo. Para ello, se realiza un análisis que, en primer lugar, abordará el tema económico, en el que se explicarán los factores que han influido positiva y negativamente, tales como: el capitalismo, la globalización, la crisis financiera... Después, se expondrá la cuestión política, haciendo referencia al marco legal europeo, los proyectos y las relaciones internacionales. Otros de los aspectos a tratar (y no menos importantes) serán los relacionados con el desarrollo cultural, el movimiento social y los impactos medioambientales. Finalmente se expondrán los distintos tipos de tecnología a los que han dado lugar estos cambios, y cómo han ido evolucionando a lo largo del tiempo, hasta la aparición de nuevas formas de comunicación. Una vez estudiadas las distintas disciplinas, se podrá “diseñar” una posible perspectiva hacia la que se dirigen las redes móviles e Internet en Europa. En definitiva, conocer de dónde venimos, qué es lo que hacemos y hacia dónde nos dirigimos. Internet was only the beginning of great changes. Since the invention of the printing press there has been such an important technological change as the age of digitization. Moreover, with the appearance of the first mobile terminal which confirmed the new revolution at this stage. This project concentrates on the European case. To do this, an analysis is performed that, in the first place board the economic issue, which will explain the factors that have influenced positively and negatively, such as capitalism, globalization, financial crisis... Then the political question will be discussed, referring to the European legal framework, projects and international relations. Other aspects to be treated (and no less important) are those related to the cultural, social movement and environmental impacts. Finally we will present the different types of technology to which these changes have led, and how they have evolved through time, until the emergence of new forms of communication. After studying the different disciplines, you can "design" a possible perspective towards that target mobile networks and Internet in Europe. In short, knowing where we came from, what we do and where we are going.

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La aplicación de criterios de sostenibilidad ha de entenderse como el procedimiento esencial para la necesaria reconversión del sector de la construcción, que movilizando el 10% de la economía mundial, representa más de la tercera parte del consumo mundial de recursos, en torno al 30-40% del consumo energético y emisiones de gases de efecto invernadero, 30-40% de la generación de residuos y el 12% de todo el gasto en agua dulce del planeta. La presente investigación se enmarca en una estrategia general de promover la evaluación de la sostenibilidad en la edificación en el contexto español, dando un primer paso centrado en la evaluación del comportamiento ambiental. El hilo conductor de la investigación parte de la necesidad de establecer un marco teórico de sostenibilidad, que permita clarificar conceptos y definir criterios de valoración adecuados. Como siguiente paso, la investigación se dirige a la revisión del panorama internacional de normativa e instrumentos voluntarios, con el objetivo de clarificar el difuso panorama que caracteriza a la sostenibilidad en el sector de la edificación en la actualidad y enmarcar la investigación en un contexto de políticas y programaciones ya existentes. El objetivo principal reside en el planteamiento de una metodología de evaluación de los aspectos o impactos ambientales asociados al ciclo de vida de la edificación, aplicable al contexto español, como una de las tres dimensiones que constituyen los pilares básicos de la sostenibilidad. Los ámbitos de evaluación de los aspectos sociales y económicos, para los que no existe actualmente un grado de definición metodológico suficientemente congruente, son adicionalmente examinados, de cara a ofrecer una visión holística de la evaluación. Previo al desarrollo de la propuesta, se aborda, en primer lugar, la descripción de las características básicas y limitaciones de la metodología de Análisis de Ciclo de Vida (ACV), para posteriormente proceder a profundizar en el estado del arte de aplicación de ACV a la edificación, realizando una revisión crítica de los trabajos de investigación que han sido desarrollados en los últimos años. Esta revisión permite extraer conclusiones sobre su grado de coherencia con el futuro entorno normativo e identificar dos necesidades prioritarias de actuación: -La necesidad de armonización, dadas las fuertes inconsistencias metodológicas detectadas, que imposibilitan la comparación de los resultados obtenidos en los trabajos de evaluación. -La necesidad de simplificación, dada la complejidad inherente a la evaluación, de modo que, manteniendo el máximo rigor, sea viable su aplicación práctica en el contexto español. A raíz de la participación en los trabajos de desarrollo normativo a nivel europeo, se ha adquirido una visión crítica sobre las implicaciones metodológicas de la normativa en definición, que permite identificar la hoja de ruta que marcará el escenario europeo en los próximos años. La definición de la propuesta metodológica integra los principios generales de aplicación de ACV con el protocolo metodológico establecido en la norma europea, considerando adicionalmente las referencias normativas de las prácticas constructivas en el contexto español. En el planteamiento de la propuesta se han analizado las posibles simplificaciones aplicables, con el objetivo de hacer viable su implementación, centrando los esfuerzos en la sistematización del concepto de equivalente funcional, el establecimiento de recomendaciones sobre el tipo de datos en función de su disponibilidad y la revisión crítica de los modelos de cálculo de los impactos ambientales. Las implicaciones metodológicas de la propuesta se describen a través de una serie de casos de estudio, que ilustran su viabilidad y las características básicas de aplicación. Finalmente, se realiza un recorrido por los aspectos que han sido identificados como prioritarios en la conformación del escenario de perspectivas futuras, líneas de investigación y líneas de acción. Abstract Sustainability criteria application must be understood as the essential procedure for the necessary restructuring of the construction sector, which mobilizes 10% of the world economy, accounting for more than one third of the consumption of the world's resources, around 30 - 40% of energy consumption and emissions of greenhouse gases, 30-40% of waste generation and 12% of all the fresh water use in the world. This research is in line with an overall strategy to promote the sustainability assessment of building in the Spanish context, taking a first step focused on the environmental performance assessment. The thread of the present research sets out from the need to establish a theoretical framework of sustainability which clarifies concepts and defines appropriate endpoints. As a next step, the research focuses on the review of the international panorama regulations and voluntary instruments, with the aim of clarifying the fuzzy picture that characterizes sustainability in the building sector at present while framing the research in the context of existing policies and programming. The main objective lies in the approach of a methodology for the assessment of the environmental impacts associated with the life cycle of building, applicable to the Spanish context, as one of the three dimensions that constitute the pillars of sustainability. The areas of assessment of social and economic issues, for which there is currently a degree of methodological definition consistent enough, are further examined, in order to provide a holistic view of the assessment. The description of the basic features and limitations of the methodology of Life Cycle Assessment (LCA) are previously addressed, later proceeding to deepen the state of the art of LCA applied to the building sector, conducting a critical review of the research works that have been developed in recent years. This review allows to establish conclusions about the degree of consistency with the future regulatory environment and to identify two priority needs for action: - The need for harmonization, given the strong methodological inconsistencies detected that prevent the comparison of results obtained in assessment works. - The need for simplification, given the inherent complexity of the assessment, so that, while maintaining the utmost rigor, make the practical application feasible in the Spanish context. The participation in the work of policy development at European level has helped to achieve a critical view of the methodological implications of the rules under debate, identifying the roadmap that will mark the European scene in the coming years. The definition of the proposed methodology integrates the general principles of LCA methodology with the protocol established in the European standard, also considering the regulatory standards to construction practices in the Spanish context. In the proposed approach, possible simplifications applicable have been analyzed, in order to make its implementation possible, focusing efforts in systematizing the functional equivalent concept, establishing recommendations on the type of data based on their availability and critical review of the calculation models of environmental impacts. The methodological implications of the proposal are described through a series of case studies, which illustrate the feasibility and the basic characteristics of its application. Finally, the main aspects related to future prospects, research lines and lines of action that have been identified as priorities are outlined.

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Commitment and involvement from the different members of an organization are two key elements for an organization to achieve its environmental excellence. Firstly, businesses are aware of the close relationship between their activities and the environment, for they are not only polluting agents but also agents with the capacity to reduce adverse environmental impacts. Secondly, the fact that employees can play a relevant role in terms of the socially responsible measures to be taken by organizations has started to become an irrefutably important issue. This piece of research is intended to help gain knowledge concerning the attitude of the two main actors in productive activity toward the environmental, that is, employers and employees; as well, this research intends to identify factors determining behaviour towards the environmental. For this, we have gathered the ideas and assessments contained in the discourse of a group of small and medium-sized businesses, large company owners and officers, employees, and work related risk prevention representatives. Qualitative work consisted of in-depth interviews and the creation of discussion groups.

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Increased globalization and outsourcing to developing countries is fostering the interest in supply chain sustainability. From the academic point of view, while environmental impacts of supply chains have been largely analysed, the research on social issues has been scattered and fragmented. This paper thereby sets out to close this gap. We have identified an emerging sphere of knowledge at the interface between sustainable supply chain management, business strategy and international development literature, which seeks to propose innovative strategies for poverty alleviation. The incorporation of impoverished farmers into supply chains is presented here as one of those strategies, and illustrated through a case study on the integration of these farmers in the Senegalese horticulture supply chain.

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La energía eólica, así como otras energías renovables, ha experimentado en la última década un gran auge que va extendiéndose alrededor de todo el mundo, cada vez más concienciado de la importancia de las energías renovables como una fuente alternativa de energía. Se han sumado al reto todos los países acogidos al Protocolo de Kyoto, que a fin de reducir emisiones están potenciando la energía eólica como la fuente de energía renovable hoy día más viable para la generación eléctrica. Brasil alcanzó en 2011 los 1.509 MW instalados, lo que representa el 50% de Latinoamérica, seguido por México con el 31%. Las características del sector eléctrico así como un marco legal favorable y el alto potencial eólico, hacen que la perspectiva de crecimiento en este tipo de energía sea muy favorable durante los próximos años, con estimaciones de unos 20.000 MW para 2020. El asentamiento del sector en el país de algunos de los fabricantes más importantes y los avances en cuanto a eficiencia de los aerogeneradores, mayor aprovechamiento de la energía de los vientos menos intensos, amplía las posibles ubicaciones de parques eólicos permitiendo una expansión grande del sector. El parque eólico objeto del proyecto está ubicado en el estado de Rio Grande do Sul, al sur del país, y está constituido por 33 aerogeneradores de 2,0 MW de potencia unitaria, lo que supone una potencia total instalada de 66 MW. La energía eléctrica generada en él será de 272,8 GWh/año. Esta energía se venderá mediante un contrato de compraventa de energía (PPA, Power Purchase Agreement) adjudicado por el gobierno Brasileño en sus sistemas de subasta de energía. En el proyecto se aborda primeramente la selección del emplazamiento del parque eólico a partir de datos de viento de la zona. Estos datos son estudiados para evaluar el potencial eólico y así poder optimizar la ubicación de las turbinas eólicas. Posteriormente se evalúan varios tipos de aerogeneradores para su implantación en el emplazamiento. La elección se realiza teniendo en cuenta las características técnicas de las máquinas y mediante un estudio de la productividad del parque con el aerogenerador correspondiente. Finalmente se opta por el aerogenerador G97-2.0 de GAMESA. La ejecución técnica del parque eólico se realiza de forma que se minimicen los impactos ambientales y de acuerdo a lo establecido en el Estudio de Impacto Ambiental realizado. Este proyecto requiere una inversión de 75,4 M€, financiada externamente en un 80 % y el 20 % con recursos propios del promotor. Del estudio económico-financiero se deduce que el proyecto diseñado es rentable económicamente y viable, tanto desde el punto de vista técnico como financiero. Abstract Wind energy, as well as other renewable energies, has experienced over the last decade a boom that is spreading around the world increasingly aware of the importance of renewable energy as an alternative energy source. All countries that ratified the Kyoto Protocol have joined the challenge promoting wind energy in order to reduce emissions as the more feasible renewable energy for power generation. In 2011 Brazil reached 1509 MW installed, 50% of Latin America, followed by Mexico with 31%. Electric sector characteristics as well as a favorable legal framework and the high wind potential, make the perspective of growth in this kind of energy very positive in the coming years, with estimates of about 20,000 MW by 2020. Some leading manufacturers have settled in the country and improvements in wind turbines efficiency with less intense winds, make higher the number of possible locations for wind farms allowing a major expansion of the sector. The planned wind farm is located in the state of Rio Grande do Sul, in the south of the Brazil, and is made up of 33 wind turbines of 2,0 MW each, representing a total capacity of 66 MW. The electricity generated, 272,8 GWh/year will be sold through a power purchase agreement (PPA) awarded by the Brazilian government in its energy auction systems. The project deals with the site selection of the wind farm from wind data in the area. These data are studied to evaluate the wind potential and thus optimize the location of wind turbines. Then several types of turbines are evaluated for implementation at the site. The choice is made taking into account the technical characteristics of the machines and a study of the productivity of the park with the corresponding turbine. Finally selected wind turbine is Gamesa G97-2.0. The technical implementation of the wind farm is done to minimize environmental impacts as established in the Environmental Impact Study. This project requires an investment of 75,4 M€, financed externally by 80% and 20% with equity from the promoter. The economic-financial study shows that the project is economically viable, both technically and financially.

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A sustainable manufacturing process must rely on an also sustainable raw materials and energy supply. This paper is intended to show the results of the studies developed on sustainable business models for the minerals industry as a fundamental previous part of a sustainable manufacturing process. As it has happened in other economic activities, the mining and minerals industry has come under tremendous pressure to improve its social, developmental, and environmental performance. Mining, refining, and the use and disposal of minerals have in some instances led to significant local environmental and social damage. Nowadays, like in other parts of the corporate world, companies are more routinely expected to perform to ever higher standards of behavior, going well beyond achieving the best rate of return for shareholders. They are also increasingly being asked to be more transparent and subject to third-party audit or review, especially in environmental aspects. In terms of environment, there are three inter-related areas where innovation and new business models can make the biggest difference: carbon, water and biodiversity. The focus in these three areas is for two reasons. First, the industrial and energetic minerals industry has significant footprints in each of these areas. Second, these three areas are where the potential environmental impacts go beyond local stakeholders and communities, and can even have global impacts, like in the case of carbon. So prioritizing efforts in these areas will ultimately be a strategic differentiator as the industry businesses continues to grow. Over the next forty years, world?s population is predicted to rise from 6.300 million to 9.500 million people. This will mean a huge demand of natural resources. Indeed, consumption rates are such that current demand for raw materials will probably soon exceed the planet?s capacity. As awareness of the actual situation grows, the public is demanding goods and services that are even more environmentally sustainable. This means that massive efforts are required to reduce the amount of materials we use, including freshwater, minerals and oil, biodiversity, and marine resources. It?s clear that business as usual is no longer possible. Today, companies face not only the economic fallout of the financial crisis; they face the substantial challenge of transitioning to a low-carbon economy that is constrained by dwindling natural resources easily accessible. Innovative business models offer pioneering companies an early start toward the future. They can signal to consumers how to make sustainable choices and provide reward for both the consumer and the shareholder. Climate change and carbon remain major risk discontinuities that we need to better understand and deal with. In the absence of a global carbon solution, the principal objective of any individual country should be to reduce its global carbon emissions by encouraging conservation. The mineral industry internal response is to continue to focus on reducing the energy intensity of our existing operations through energy efficiency and the progressive introduction of new technology. Planning of the new projects must ensure that their energy footprint is minimal from the start. These actions will increase the long term resilience of the business to uncertain energy and carbon markets. This focus, combined with a strong demand for skills in this strategic area for the future requires an appropriate change in initial and continuing training of engineers and technicians and their awareness of the issue of eco-design. It will also need the development of measurement tools for consistent comparisons between companies and the assessments integration of the carbon footprint of mining equipments and services in a comprehensive impact study on the sustainable development of the Economy.

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Direct Steam Generation (DSG) in Linear Fresnel (LF) solar collectors is being consolidated as a feasible technology for Concentrating Solar Power (CSP) plants. The competitiveness of this technology relies on the following main features: water as heat transfer fluid (HTF) in Solar Field (SF), obtaining high superheated steam temperatures and pressures at turbine inlet (500ºC and 90 bar), no heat tracing required to avoid HTF freezing, no HTF degradation, no environmental impacts, any heat exchanger between SF and Balance Of Plant (BOP), and low cost installation and maintenance. Regarding to LF solar collectors, were recently developed as an alternative to Parabolic Trough Collector (PTC) technology. The main advantages of LF are: the reduced collector manufacturing cost and maintenance, linear mirrors shapes versus parabolic mirror, fixed receiver pipes (no ball joints reducing leaking for high pressures), lower susceptibility to wind damages, and light supporting structures allowing reduced driving devices. Companies as Novatec, Areva, Solar Euromed, etc., are investing in LF DSG technology and constructing different pilot plants to demonstrate the benefits and feasibility of this solution for defined locations and conditions (Puerto Errado 1 and 2 in Murcia Spain, Lidellin Newcastle Australia, Kogran Creek in South West Queensland Australia, Kimberlina in Bakersfield California USA, Llo Solar in Pyrénées France,Dhursar in India,etc). There are several critical decisions that must be taken in order to obtain a compromise and optimization between plant performance, cost, and durability. Some of these decisions go through the SF design: proper thermodynamic operational parameters, receiver material selection for high pressures, phase separators and recirculation pumps number and location, pipes distribution to reduce the amount of tubes (reducing possible leaks points and transient time, etc.), etc. Attending to these aspects, the correct design parameters selection and its correct assessment are the main target for designing DSG LF power plants. For this purpose in the recent few years some commercial software tools were developed to simulatesolar thermal power plants, the most focused on LF DSG design are Thermoflex and System Advisor Model (SAM). Once the simulation tool is selected,it is made the study of the proposed SFconfiguration that constitutes the main innovation of this work, and also a comparison with one of the most typical state-of-the-art configuration. The transient analysis must be simulated with high detail level, mainly in the BOP during start up, shut down, stand by, and partial loads are crucial, to obtain the annual plant performance. An innovative SF configurationwas proposed and analyzed to improve plant performance. Finally it was demonstrated thermal inertia and BOP regulation mode are critical points in low sun irradiation day plant behavior, impacting in annual performance depending on power plant location.

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Transportation modes produce many external costs such as congestion, accidents, and environmental impacts (pollution, noise and so on). From the microeconomic theory it is well known that in order to maximize social welfare, transportation modes should internalize the marginal costs they produce. Allocative efficiency is achieved when all transportation modes are priced at their social marginal cost. The objective of this research is to evaluate to what extent different passenger transport modes internalize their social marginal costs. This analysis is important since it affects the competitiveness of the different transport modes for a given OD pair. The case study analyzed is the corridor Madrid-Barcelona in Spain and the different transport modes have been considered (cars, buses, high-speed train and air). The research calculates the marginal social cost per user for each transportation mode, and it compares it with the average fare—allowing for the effect of discriminatory taxes—currently paid by the users. The external costs are calculated according to the guidelines established by the European Union. The gap between the marginal social cost and the price paid by users will provide the extra cost per passenger that each transport mode should have to pay for internalizing the external cost it produces. The research shows that external costs already produced by road and air transport modes are much higher than those produced by rail. However, the results show that road transport already internalizes every external costs it produces because users pay high fuel taxes. In other words, although rail transportation produces lower external costs, road transportation pays more than it should on the basis of the social marginal costs. The results of this work might be of help for Europ ean policy actions to be undertaken in the future.

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The complexity of climate change and its evolution during the last few years has a positive impact on new developments and approaches to reduce the emissions of CO2. Looking for a methodology to evaluate the sustainability of a roadway, a tool has been developed. Life Cycle Assessment (LCA) is being accepted by the road industry to measure and evaluate the environmental impacts of an infrastructure, as the energy consumption and carbon footprint. This paper describes the methodology to calculate the CO2 emissions associated with the energy embodied on a roadway along its life cycle, including construction, operations and demolition. It will assist to find solutions to improve the energy footprint and reduce the amount of CO2 emissions. Details are provided of both, the methodology and the data acquisition. This paper is an application of the methodology to the Spanish highways, using a local database. Two case studies and a practical example are studied to show the model as a decision support for sustainable construction in the road industry.

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Las evidencias del impacto sobre el medio ambiente asociado al funcionamiento de las ciudades hacen que sea urgente proponer medidas que reduzcan este consumo y mejoren la eficiencia del metabolismo urbano. La existencia de límites en la disponibilidad de recursos materiales y energéticos, plantea actualmente un reto importante al ser humano: ¿son posibles otras formas de organización más adecuadas a esta condición de limitación? Para dar respuesta, resulta fundamental conocer cómo interactuarán nuestros sistemas urbanos en un modelo económico de continuo desarrollo, con la población que alojan, y si podrán adaptarse a la capacidad de carga limitada del Planeta, evitando futuras situaciones de colapso anunciadas desde distintos ámbitos científicos. En ese contexto, la tesis formula un método de análisis del alojamiento que, mediante la evaluación a largo plazo, permita proponer medidas de intervención para reducir el consumo de recursos asociado a su funcionamiento. Se parte de un enfoque ecológico para definir el alojamiento como una parte fundamental del sistema urbano, que está compuesto por tres elementos: habitantes, viviendas y recursos naturales; por tanto, para reducir los impactos asociados al alojamiento es necesario tener en cuenta la diferente naturaleza de estos elementos y el carácter dinámico de las relaciones que se producen entre ellos. La Ecología, a través del estudio de los ecosistemas, ha identificado estrategias de supervivencia y adaptación ante los cambios y perturbaciones. La similitud entre los elementos de un ecosistema (población y soporte) y los del alojamiento (habitantes, viviendas y recursos naturales) permite verificar que la aplicación de estas estrategias al alojamiento puede conducir a situaciones más deseables en la relación de los sistemas urbanos con su entorno A partir de esta hipótesis, se propone un método de análisis diacrónico1 o a largo plazo, para conocer la evolución en el tiempo del alojamiento a través de la cuantificación de una serie de indicadores descriptivos de los habitantes, las viviendas y los recursos naturales. La aplicación de este método a un sistema urbano permitiría conocer las características de los elementos del sistema y, para un ámbito temporal de futuro, prever su evolución, identificar escenarios no deseables y proponer medidas de intervención que corrijan anticipadamente estas situaciones y eviten impactos ambientales innecesarios. La validación del método de análisis se realiza mediante la aplicación al caso de Madrid en periodo retrospectivo (de 1940 a 2010) A partir del estudio de la evolución en Madrid de los indicadores seleccionados, se proponen medidas de intervención en el alojamiento basadas en estrategias ecológicas que habrían conducido a una evolución alternativa con un impacto menor sobre el medio ambiente que la situación actual. El método de análisis se aplica con carácter prospectivo definiendo tres escenarios de futuro para Madrid hasta 2100. Para cada uno de ellos se analiza la evolución previsible de los indicadores y se proponen diferentes medidas de intervención que, desde el punto de vista ecológico, conducirían a una situación más adecuada. La tesis concluye en el interés de este método de análisis diacrónico que permite estimar posibilidades en la evolución futura del alojamiento, identificar las necesidades de recursos para responder a las demandas de los habitantes y, desde un enfoque ecológico, definir, cuantificar y evaluar posibles medidas de intervención que reduzcan los impactos ambientales. El método, por tanto, es una herramienta de interés para la toma de decisiones en la intervención en el alojamiento y en la planificación urbana a largo plazo. ABSTRACT Evidence of the impact on the environment associated with the operation of cities make it urgent to propose measures to reduce energy consumption and improve the efficiency of urban metabolism. The limited availability of materials and energy resources currently poses a significant challenge to human beings: are more appropriate forms of organization for this limitation possible? In response, it is essential to know how our urban systems with the population they host will interact in an economic model of continuous development and whether they can adapt to the limited endurance capacity of the planet, thus avoiding future collapse situations which are being announced from different scientific fields. In this context, the thesis puts forward a method of housing analysis that by a long term assessment will enable to propose intervention measures to reduce resource consumption associated with its operation. The thesis is based on an ecological approach to identify housing as a fundamental part of the urban system, which is composed of three elements: inhabitants, homes and natural resources. Therefore, in order to reduce the impacts associated with housing it is necessary to consider the characteristics of these elements and the dynamic nature of the relationships among them. Ecology, through the analysis of ecosystems, has identified strategies for survival and adaptation to changes and disturbances. The similarity between the elements of an ecosystem (population and support) and housing (inhabitants, homes and natural resources) enables to verify that the implementation of these strategies to housing can lead to better situations in the relationship existing between urban systems with their environment. From this hypothesis, a diachronic or long term analysis method is proposed to know the evolution of housing over time through the quantification of a descriptive indicators series of inhabitants, homes and natural resources. The implementation of this method to a urban system would allow better knowledge of the characteristics of these elements and forecast their development, identify undesirable scenarios and propose early intervention measures to correct these situations and avoid unnecessary environmental impacts. The validation of the method of analysis has been proved in the city of Madrid for the years 1940-2010. From the analysis of the evolution of the indicators selected, accommodation intervention measures are proposed based on ecological strategies that would have led to an alternative development having less impact on the environment than that of the current situation. The analysis method is implemented prospectively defining three future scenarios for the city of Madrid until 2100. The likely evolution of the indicators are analyzed for each scenario and various intervention measures that would lead to a better situation from an ecological point of view are proposed. The thesis conclusion states the interest of this diachronic analysis method to estimate potential future developments in the housing field, identify resource requirements to meet the demands of the citizens and, from an ecological approach, define, quantify and assess possible intervention measures to reduce environmental impacts. The method, therefore, is an interesting tool for decision-making process as for the intervention in housing and urban planning in the long term.

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Economic growth has traditionally been linked to road freight transport demand, leading to a steady rise in social and environmental impacts. Concern about this problem has caused the EU to promote a decoupling strategy aimed at boosting sustainable development in European countries by improving the efficiency of transport systems without curbing economic growth. Over the last few years empirical evidence in some countries such as the United Kingdom has shown an increase in GDP while the volume of road freight traffic has remained stable or even decreased. This paper compares recent decoupling trends by analyzing the evolution of road tonne-kms/GDP relationship in the United Kingdom and Spain from 1999 to 2007. This comparison seeks to identify the main differences and key drivers of decoupling in both countries. We first provide an overview of the divergences between both economic structures and levels of road transport intensity. Then we conduct a decomposition analysis in order to identify the variables that explain the evolution of truck traffic per unit of GDP in each country. The results show that the increasing share of services in GDP has substantially contributed to decreasing road transport demand in both cases. Changes in road transport intensity due to improvements in logistic and supply chain management have been more successful in the UK than in Spain.

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En los últimos años, debido a la creciente preocupación por el calentamiento global y el cambio climático, uno de los retos más importantes a los que se enfrenta nuestra sociedad es el uso eficiente y económico de energía así como la necesidad correspondiente de reducir los gases de efecto invernadero (GEI). Las tecnologías de mezclas semicalientes se han convertido en un nuevo e importante tema de investigación en el campo de los materiales para pavimentos ya que ofrece una solución potencial para la reducción del consumo energético y las emisiones de GEI durante la producción y puesta en obra de las mezclas bituminosas. Por otro lado, los pavimentos que contienen polvo de caucho procedente de neumático fuera de uso, al hacer uso productos de desecho, ahorran energía y recursos naturales. Estos pavimentos ofrecen una resistencia mejorada a la formación de roderas, a la fatiga y a la fisuración térmica, reducen los costes de mantenimiento y el ruido del tráfico así como prolongan la vida útil del pavimento. Sin embargo, estas mezclas presentan un importante inconveniente: la temperatura de fabricación se debe aumentar en comparación con las mezclas asfálticas convencionales, ya que la incorporación de caucho aumenta la viscosidad del ligante y, por lo tanto, se producen mayores cantidades de emisiones de GEI. En la presente Tesis, la tecnología de mezclas semicalientes con aditivos orgánicos (Sasobit, Asphaltan A, Asphaltan B, Licomont) se incorporó a la de betunes de alta viscosidad modificados con caucho (15% y 20% de caucho) con la finalidad de dar una solución a los inconvenientes de mezclas con caucho gracias a la utilización de aditivos reductores de la viscosidad. Para este fin, se estudió si sería posible obtener una producción más sostenible de mezclas con betunes de alto contenido en caucho sin afectar significativamente su nivel de rendimiento mecánico. La metodología aplicada para evaluar y comparar las características de las mezclas consistió en la realización de una serie de ensayos de laboratorio para betunes y mezclas con caucho y con aditivos de mezclas semicalientes y de un análisis del ciclo de vida híbrido de la producción de mezclas semicalientes teniendo en cuenta la papel del aditivo en la cadena de suministro con el fin de cuantificar con precisión los beneficios de esta tecnología. Los resultados del estudio indicaron que la incorporación de los aditivos permite reducir la viscosidad de los ligantes y, en consecuencia, las temperaturas de producción y de compactación de las mezclas. Por otro lado, aunque la adición de caucho mejoró significativamente el comportamiento mecánico de los ligantes a baja temperatura reduciendo la susceptibilidad al fenómeno de fisuración térmica, la adición de las ceras aumentó ligeramente la rigidez. Los resultados del estudio reológico mostraron que la adición de porcentajes crecientes de caucho mejoraban la resistencia del pavimento con respecto a la resistencia a la deformación permanente a altas temperaturas y a la fisuración térmica a bajas temperaturas. Además, se observó que los aditivos mejoran la resistencia a roderas y la elasticidad del pavimento al aumentar el módulo complejo a altas temperaturas y al disminuir del ángulo de fase. Por otra parte, el estudio reológico confirmó que los aditivos estudiados aumentan ligeramente la rigidez a bajas temperaturas. Los ensayos de fluencia llevados a cabo con el reómetro demostraron una vez más la mejora en la elasticidad y en la resistencia a la deformación permanente dada por la adición de las ceras. El estudio de mezclas con caucho y aditivos de mezclas semicalientes llevado a cabo demostró que las temperaturas de producción/compactación se pueden disminuir, que las mezclas no experimentarían escurrimiento, que los aditivos no cambian significativamente la resistencia conservada y que cumplen la sensibilidad al agua exigida. Además, los aditivos aumentaron el módulo de rigidez en algunos casos y mejoraron significativamente la resistencia a la deformación permanente. Asimismo, a excepción de uno de los aditivos, las mezclas con ceras tenían la misma o mayor resistencia a la fatiga en comparación con la mezcla control. Los resultados del análisis de ciclo de vida híbrido mostraron que la tecnología de mezclas semicalientes es capaz de ahorrar significativamente energía y reducir las emisiones de GEI, hasta un 18% y 20% respectivamente, en comparación con las mezclas de control. Sin embargo, en algunos de los casos estudiados, debido a la presencia de la cera, la temperatura de fabricación debe reducirse en un promedio de 8 ºC antes de que los beneficios de la reducción de emisiones y el consumo de combustible puedan ser obtenidos. Los principales sectores contribuyentes a los impactos ambientales generados en la fabricación de mezclas semicalientes fueron el sector de los combustibles, el de la minería y el de la construcción. Due to growing concerns over global warming and climate change in recent years, one of the most important challenges facing our society is the efficient and economic use of energy, and with it, the corresponding need to reduce greenhouse gas (GHG) emissions. The Warm Mix Asphalt (WMA) technology has become an important new research topic in the field of pavement materials as it offers a potential solution for the reduction of energy consumption and GHG emissions during the production and placement of asphalt mixtures. On the other hand, pavements containing crumb-rubber modified (CRM) binders save energy and natural resources by making use of waste products. These pavements offer an improved resistance to rutting, fatigue and thermal cracking; reduce traffic noise and maintenance costs and prolong pavement life. These mixtures, however, present one major drawback: the manufacturing temperature is higher compared to conventional asphalt mixtures as the rubber lends greater viscosity to the binder and, therefore, larger amounts of GHG emissions are produced. In this dissertation the WMA technology with organic additives (Sasobit, Asphaltan A, Asphaltan B and Licomont) was applied to CRM binders (15% and 20% of rubber) in order to offer a solution to the drawbacks of asphalt rubber (AR) mixtures thanks to the use of fluidifying additives. For this purpose, this study sought to determine if a more sustainable production of AR mixtures could be obtained without significantly affecting their level of mechanical performance. The methodology applied in order to evaluate and compare the performance of the mixtures consisted of carrying out several laboratory tests for the CRM binders and AR mixtures with WMA additives (AR-WMA mixtures) and a hybrid input-output-based life cycle assessment (hLCA) of the production of WMA. The results of the study indicated that the incorporation of the organic additives were able to reduce the viscosity of the binders and, consequently, the production and compaction temperatures. On the other hand, although the addition of rubber significantly improved the mechanical behaviour of the binders at low temperatures reducing the susceptibility to thermal cracking phenomena, the addition of the waxes slightly increased the stiffness. Master curves showed that the addition of increasing percentages of rubber improved the resistance of the pavement regarding both resistance to permanent deformation at high temperatures and thermal cracking at low temperatures. In addition, the waxes improved the rutting resistance and the elasticity as they increased the complex modulus at high temperatures and decreased the phase angle. Moreover, master curves also attest that the WMA additives studied increase the stiffness at low temperatures. The creep tests carried out proved once again the improvement in the elasticity and in the resistance to permanent deformation given by the addition of the waxes. The AR-WMA mixtures studied have shown that the production/compaction temperatures can be decreased, that the mixtures would not experience binder drainage, that the additives did not significantly change the retained resistance and fulfilled the water sensitivity required. Furthermore, the additives increased the stiffness modulus in some cases and significantly improved the permanent deformation resistance. Except for one of the additives, the waxes had the same or higher fatigue resistance compared to the control mixture. The results of the hLCA demonstrated that the WMA technology is able to significantly save energy and reduce GHG emissions, up to 18% and 20%, respectively, compared to the control mixtures. However, in some of the case studies, due to the presence of wax, the manufacturing temperature at the asphalt plant must be reduced by an average of 8ºC before the benefits of reduced emissions and fuel usage can be obtained. The results regarding the overall impacts generated using a detailed production layer decomposition indicated that fuel, mining and construction sectors are the main contributors to the environmental impacts of manufacturing WMA mixtures.

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El sector del transporte por carretera es uno de los principales contribuyentes de consumo de combustible y emisiones de España. Por lo tanto, la evaluación de los impactos ambientales del tráfico rodado es esencial para los programas de mitigación del cambio climático y la eficiencia energética. Sin embargo, uno de los retos en la planificación del transporte y el diseño de políticas consiste en la aplicación de metodologías de evaluación de emisiones consistentes, el diseño de estrategias y la evaluación de su eficacia. Las metodologías existentes de evaluación de las emisiones del transporte por carretera, utilizan diferentes niveles de análisis y períodos. Sin embargo, estos análisis son puntuales y no existe una continuidad en el análisis de diferentes estrategias o políticas. Esta tesis doctoral proporciona conocimientos y herramientas para el análisis de las políticas destinadas a reducir las emisiones de tráfico, tomando España como caso de estudio. La investigación se estructura en dos partes: i) el desarrollo y aplicación de metodologías para el análisis de factores y políticas que contribuyen en la evolución de las emisiones GEI del transporte por carretera en España; desde una perspectiva nacional; y ii) el desarrollo y aplicación de un marco metodológico para estimar las emisiones del tráfico interurbano y de evaluar estrategias centradas en la operación del tráfico y en la infraestructura. En resumen, esta tesis demuestra la idoneidad de utilizar diferentes herramientas para analizar las emisiones de tráfico desde diferentes puntos de vista. Desde el diseño de políticas de mitigación y eficiencia energética a nivel nacional, a estrategias centradas en la operación del tráfico interurbano y la infraestructura. Road transport is one of the major contributors to fuel consumption and emissions in Spain. Consequently, assessing the environmental impacts of road traffic is essential for climate change mitigation and energy efficiency programs. However, one of the key challenges of policy makers and transport planners consists of implementing consistent assessment emissions methodologies, applying mitigation strategies, and knowing their effectiveness. Current state-of-the-art emissions assessment methodologies estimate emissions from different levels and periods, using different approaches. Nevertheless, these studies are timely and they usually take different methodologies for analysing different strategies or policies, regardless of the assessment as a whole. This doctoral thesis provides knowledge and methodologies for analysing policies designed to reduce road traffic emissions, using the case study of Spain. The research procedure consists of two main scopes: i) the development and application of methodologies for analysing key factors and policies driving the GHG emissions of road transport in Spain; from a national perspective; and ii) the development and application of a road traffic emissions model for assessing operational and infrastructure strategies of the interurban road network at segment level. In summary, this thesis demonstrates the appropriateness to use different tools to analyse road traffic emissions at different levels: from appropriate nationwide mitigation and energy efficiency policies, to strategies focused on the operation of interurban traffic and infrastructure.

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The paper describes some relevant results of an on-going research aiming to elaborate a methodology to help the mobility management in natural parks, compatible with their protection missions: it has been developed a procedure to reproduce the mobility-environment relationships in various operational conditions. The final purpose is the identification of: a) the effects of various choices in transport planning, both at long term and strategic level; b) the most effective policies of mobility management. The work is articulated in the following steps: 1) definition of protected area on the basis of ecological and socio-economic criteria and legislative constraints; 2) analysis of mobility needs in the protected areas; 3) reconstruction of the state of the art of mobility management in natural parks at European level; 4) analysis of used traffic flows measurement methods; 5) analysis of environmental impacts due to transport systems modelling (air pollution and noise only); 6) identification of mitigation measures to be potentially applied. The whole methodology has been tested and validated on Italian case studies: i) the concerned area has been zoned according to the land-use peculiarities; ii) the local situations of transport infrastructure (roads and parking), services (public transport systems) and rules (traffic regulations) have been mapped with references to physical and functional attributes; iii) the mobility, both systematic and touristic, has been represented in an origin-destination matrix. By means of an assignment model the flows have been distributed and the corresponding average speeds to quantify gaseous and noise emissions was calculated, the criticalities in the reference scenario have been highlighted, as well as some alternative scenarios, including both operational and infrastructural measures have been identified. The comparison between projects and reference scenario allowed the quantification of effects (variation of emissions) for each scenario and a selection of the most effective management actions to be taken.

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The final purpose is the identification of: a) the effects of various choices in transport planning, both at long term and strategic level; b) the most effective policies of mobility management. The preliminary work was articulated in the following steps: 1) definition of protected area on the basis of ecological and socio-economic criteria and legislative constraints; 2) analysis of mobility needs in the protected areas; 3) reconstruction of the state of the art of mobility management in natural parks at European level; 4) analysis of used traffic flows measurement methods; 5) analysis of environmental impacts due to transport systems modelling (limited to air pollution and noise); 6) identification of mitigation measures to the potentially applied. The whole methodology has been firstly tested on the case study of the National Park of ?Gran Sasso and Monti della Laga? and further validated on the National Park of ?Gargano?, both located Italy: i) the concerned area has been zoned according to the land-use peculiarities; ii) the local situations of transport infrastructure (roads and parking), services (public transport systems) and rules (traffic regulations) have been mapped with references to physical and functional attributes; iii) the mobility, both systematic and touristic, has been synthetically represented in an origin-destination matrix. By means of an assignment model it has been determined the distribution of flows and the corresponding average speeds to quantify gaseous and noise emissions. On this basis the environmental criticalities in the reference scenario have been highlighted, as well as some alternative scenarios including both operational and infrastructural measures have been identified. The comparison between the projects and the reference scenario allowed the quantification of the effects (variation of emissions) for each scenario and a selection of the most effective management actions to be taken.