19 resultados para Private fleet

em Universidad Politécnica de Madrid


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Esta tesis investiga cuales son los parámetros más críticos que condicionan los resultados que obtienen en los ensayos de protección de peatones la flota Europea de vehículos, según la reglamentación europea de protección de peatones de 2003 (Directiva CE 2003/102) y el posterior Reglamento de 2009 (Reglamento CE 2009/78). En primer lugar se ha analizado el contexto de la protección de peatones en Europa, viendo la historia de las diferentes propuestas de procedimientos de ensayo así como los cambios (y las razones de los mismos) que han sufrido a lo largo del proceso de definición de la normativa Europea. Con la información disponible de más de 400 de estos ensayos se han desarrollado corredores de rigidez para los frontales de los diferentes segmentos de la flota de vehículos europea, siendo este uno de los resultados más relevantes de esta tesis. Posteriormente, esta tesis ha realizado un estudio accidentológico en detalle de los escenarios de atropello de peatones, identificando sus características más relevantes, los grupos de población con mayor riesgo y los tipos de lesiones más importantes que aparecen (en frecuencia y severidad), que han sentado las bases para analizar con modelos matemáticos hasta qué punto los métodos de ensayo propuestos realmente tienen estos factores en cuenta. Estos análisis no habrían sido posibles sin el desarrollo de las nuevas herramientas que se presentan en esta tesis, que permiten construir instantáneamente el modelo matemático de cualquier vehículo y cualquier peatón adulto para analizar su iteración. Así, esta tesis ha desarrollado una metodología rápida para desarrollar modelos matemáticos de vehículos a demanda, de cualquier marca y modelo y con las características geométricas y de rigidez deseados que permitan representarlo matemáticamente y del mismo modo, ha investigado cómo evoluciona el comportamiento del cuerpo humano durante el envejecimiento y ha implementado una funcionalidad de escalado en edad al modelo de peatón en multicuerpo de MADYMO (ya escalable en tamaño) para permitir modelar ad hoc cualquier peatón adulto (en género y edad). Finalmente, esta tesis también ha realizado, utilizando modelos de elementos finitos del cuerpo humano, diferentes estudios sobre la biomecánica de las lesiones más frecuentes de este tipo de accidentes, (en piernas y cabeza) con el objetivo de mejorar los procedimientos de ensayo para que predigan mejor el tipo de lesiones que se quieren evitar. Con el marco temporal y las condiciones de contorno de esta tesis se han centrado los esfuerzos en reforzar algunos aspectos críticos pero puntuales sobre cómo mejorar el ensayo de cabeza y, sobretodo, en proponer soluciones viables y con un valor añadido real al ensayo de pierna contra parachoques, sin cambiar la esencia del mismo pero proponiendo un nuevo impactador mejorado que incorpore una masa extra que representa a la parte superior del cuerpo y sea válido para toda la flota europea de vehículos independiente de la geometría de su frontal.

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Public Private Partnerships (PPPs) are mostly implemented to circumvent budgetary constraints, and to encourage efficiency and quality in the provision of public infrastructure in order to reach social welfare. One of the ways of reaching the latter objective is by the introduction of performance based standards tied to bonuses and penalties to reward or punish the performance of the contractor. This paper focuses on the implementation of safety based incentives in PPPs in such a way that the better the safety outcome the greater larger will be the economic reward to the contractor. The main aim of this paper is to identify whether the incentives to improve road safety in PPPs are ultimately effective in improving safety ratios in Spain. To that end, Poisson and negative binomial regression models have been applied using information of motorways of the Spanish network of 2006. The findings indicate that even though road safety is highly influenced by variables that are not much controllable by the contractor such as the Average Annual Daily Traffic and the percentage of heavy vehicles, the implementation of safety incentives in PPPs has a positive influence in the reduction of fatalities, injuries and accidents.

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Actualmente se está empezando a consolidar una nueva forma de gestionar la conservación y mantenimiento de la red viaria de las Administraciones Públicas, basándose en contratos de colaboración público-privadas (PPP). Las motivaciones que están provocando este movimiento son de diversa índole. Por un lado, en el seno de la Unión Europea, existen serias restricciones presupuestarias debido al alto endeudamiento del sector público, lo que está llevando a buscar la forma óptima de disminuir el endeudamiento público, sin dejar de prestar servicios a la sociedad como la conservación y mantenimiento de las redes viarias. Por esta vertiente, se trata de convertir contratos convencionales de conservación viaria a esquemas de colaboración público-privada, donde se transferiría al sector privado el riesgo de disponibilidad de la vía mediante el uso de indicadores de calidad y servicio. Con esta transferencia de riesgo, junto con la transferencia del riesgo de demanda/construcción, no consolidaría la deuda de la sociedad de propósito específico constituida para la gestión del contrato de colaboración público-privada dentro de las cuentas públicas, con lo que se conseguiría no aumentar el déficit público, permitiendo continuar ofreciendo el servicio demandado por la sociedad. Por otro lado, la segunda motivación del desarrollo de este tipo de contratos, no tan economicista como la anterior y más enfocada a la gestión, se trata de utilizar los contratos de gestión basados en el uso de indicadores de calidad de servicio para mejorar las prestaciones de la red viaria competencia de una Administración. Con el uso de estos indicadores, el gestor tiene una herramienta muy útil para controlar la actividad del sector privado y asegurar que se ofrece un buen servicio. En la presente tesis, la investigación se ha centrado más en la vertiente de los indicadores de calidad relacionados con la gestión eficiente de las vías objeto de conservación y mantenimiento mediante el empleo de contratos de gestión privada que utilicen este tipo de herramientas de control, monitorización y gestión. En una primera parte, la presente tesis estudia el estado de la red de carreteras, referido principalmente a España, comparando su estado con el resto de redes de carreteras de Europa, detectando las principales carencias de la misma, sobre todo en cuanto a la gestión y conservación de firmes. En un segundo bloque, la tesis analiza el estado del arte de los nuevos procedimientos de gestión de la conservación y mantenimiento basados en indicadores de calidad del servicio en el mundo, destacándose que se trata de un tema relativamente reciente, con gran interés para el sector de la gestión y financiación de infraestructuras viarias. Al ser tan novedoso, por la falta de experiencias previas, las distintas Administración, tanto propias como foráneas, han pecado de un exceso de celo a la hora de establecer los umbrales sobre los que giran los distintos indicadores de calidad de servicio que permiten controlar la gestión de la conservación y mantenimiento de la vía. Partiendo de la labor de análisis descrita, la tesis realiza una investigación más detallada de los indicadores de calidad de servicio correspondientes a firmes bituminosos, debido a que estos indicadores son los más delicados y decisivos a la hora de realizar una correcta gestión de la vía a largo plazo. Dentro de los indicadores de firmes bituminosos, se ha realizado un modelo específico de evolución de comportamiento a lo largo del tiempo de la regularidad superficial, parámetro básico para numerosas Administraciones y organismos investigadores para poder conocer la evolución de un firme a lo largo del tiempo. A esta metodología se le ha dado el nombre de Modelo JRB para evaluar la racionalidad económica de indicadores de calidad asociados a parámetros de firmes. El modelo propuesto básicamente evalúa el valor óptimo desde la perspectiva económica que ha de tener el parámetro técnico que defina alguna propiedad del firme, aplicado a la definición de los indicadores de calidad de servicio. Esta visión del valor umbral del indicador deja a un lado consideraciones de equidad o de cualquier otra índole, basándose más en una visión económica. La metodología del Modelo JRB se puede aplicar a cualquier indicador de calidad relacionado con firmes, ya que lo que se obtiene es el valor óptimo económico que debería tener el umbral del indicador de calidad. El Modelo JRB consta de varias fases. En las primeras etapas el Modelo realiza el cálculo de los costes totales de transporte utilizando como herramienta el software HDM-IV desarrollado por el Banco Mundial. En etapas posteriores, el Modelo realiza análisis de sensibilidad para distintas propuestas de sección de firme, intensidades de tráfico y restricciones al parámetro técnico que define el indicador de calidad de servicio. Como ejercicio práctico de cara a contrastar la metodología del Modelo JRB se ha realizado un Caso de Estudio. Se ha tomado un tramo teórico, con características similares a la red de carreteras española, y con una flota vehicular similar a la española, donde se ha elegido como indicador de calidad la regularidad superficial (IRI). Con las sensibilidades realizadas con el Modelo JRB, se ha determinado el rango de valores que debería tener un indicador de calidad basado en el IRI para que dichos valores fueran óptimos desde la perspectiva económica Nowadays is becoming a new way to manage O&M (operation and maintenance) in public road networks, based on PPP contracts (public-private partnership). There are several issues which are driving this trend. On the one hand, EU (European Union) has serious budgetary constraints due to the high public sector borrowing. EU politicians are looking for the best way to reduce public debt, keeping services to society such as O&M of road networks. For this aspect, conventional O&M contracts are switching to PPP scenarios, where availability risk would be transfer to private sector using PI (performance indicators), along with demand risk transfer With this risk transference, along with the transfer of demand/construction risk, SPV (specific purpose vehicle) debt doesn’t consolidate in public accounts, so deficit wouldn’t increase, allowing the continuation of services demanded by society. On the other hand, the second motivation for developing this kind of contracts, not so economist as above and more focused to management, it is about using O&M contracts based on the use of PI to improve road network maintenance. Using these indicators, manager has a very useful tool to monitor private sector activity and ensure that it is provided a good service. In this thesis, the research has been focused on PI quality aspect, related with efficient management of PPP contracts for roads, which use these tools for control, monitoring and management. In the first part, this thesis examines the state of road network, based mainly in Spain, comparing with other road networks in Europe, identifying the main gaps in it, especially with regard to the management and maintenance of pavements. In a second block, the thesis analyzes the state of art of new O&M contracts based on PI in the world, emphasizing that they are relatively recent. These kinds of contracts have a great interest in road management and financing sector. Administrations all around the world have launch tenders with very exigent PI thresholds due to several factors: this knowledge is a new area, the lack of previous experiences and the variety of Administrations which have bid these contracts. Building on the described analysis, thesis develops a more detailed research about PI for bituminous pavements, because these PI are the most delicate and decisive in making a proper long term road management. Among bituminous pavements PI, IRI (International Roughness Index) has been analyzed with more detail and has been developed a specific model of behaviour evolution over time for evenness (IRI), basic parameter for many administrations and research departments in order to know the evolution of a pavement over time. This methodology has been given the name of JRB Model to evaluate the economic rationality of performance indicators associated with pavements parameters. The proposed model basically evaluates the optimal value from an economic perspective it must have the technical parameter which defines some pavement characteristic applied to the definition of performance indicators. This point of view of indicator value threshold sets aside justice considerations or otherwise, based more on an economic perspective. JRB Model methodology can be applied to any performance indicator associated to pavements, because what you get is the economic optimum threshold should have the performance indicator. JRB Model consists of several phases. In the early stages, the Model calculates transport total cost using HDM-IV software, developed by the World Bank, as a tool. In later stages, the Model performs sensitivity analyzes for different pavement section, AADT and restrictions to the technical parameter which defines the performance indicator. As a practical exercise to test JRB Model methodology, it has done a Case Study. It has taken a theoretical section, with similar characteristics to Spanish road network, and a vehicles fleet similar to Spanish. Evenness (IRI) was chosen as a performance indicator. JRB Model calculated some sensitivities, which were useful to determined thresholds range for pavement performance indicators based on IRI to be optimal from an economic perspective.

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This paper shows the results of a research aimed to formulate a general model for supporting the implementation and management of an urban road pricing scheme. After a preliminary work, to define the state of the art in the field of sustainable urban mobility strategies, the problem has been theoretically set up in terms of transport economy, introducing the external costs’ concept duly translated into the principle of pricing for the use of public infrastructures. The research is based on the definition of a set of direct and indirect indicators to qualify the urban areas by land use, mobility, environmental and economic conditions. These indicators have been calculated for a selected set of typical urban areas in Europe on the basis of the results of a survey carried out by means of a specific questionnaire. Once identified the most typical and interesting applications of the road pricing concept in cities such as London (Congestion Charging), Milan (Ecopass), Stockholm (Congestion Tax) and Rome (ZTL), a large benchmarking exercise and the cross analysis of direct and indirect indicators, has allowed to define a simple general model, guidelines and key requirements for the implementation of a pricing scheme based traffic restriction in a generic urban area. The model has been finally applied to the design of a road pricing scheme for a particular area in Madrid, and to the quantification of the expected results of its implementation from a land use, mobility, environmental and economic perspective.

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Many countries around the world are implementing Public?Private?Partnership (PPP) contacts to manage road infrastructure. In some of these contracts the public sector introduces economic incentives to the private operator to foster the accomplishment of social goals. One of the incentives that have been introduced in some PPP contracts is related to safety in such a way that the better the safety outcome the greater will be the economic reward to the contractor. The aim of this paper is at identify whether the incentives to improve road safety in highway PPPs are ultimately effective in improving safety ratios. To this end Poisson and negative binomial regression models have been applied using information from highway sections in Spain. The findings indicate that even though road safety is highly influenced by variables that are not much controllable by the contractor such as the Average Annual Daily Traffic and the percentage of heavy vehicles, the implementation of safety incentives in PPPs has a positive influence in the reduction of fatalities, injuries and accidents.

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The aim of this paper is to call into question those typologies conventionally used in developing the post-industrial urban fabric (streets, cityblocks, slabs, etc.), often catering to urban designs based on speculative interests and completely overlooking community interests. By defining the concepts of ?postpublic space? and ?reversible urban entities? and illustrating them with an exemplary case of Spanish residential architecture from the 1960s, we establish one possible way of tackling contemporary urban-residential projects. This alternative approach considers the relationship between residential systems and open space systems and promotes the continuity and/or alternation of scales between house and city in an effort to improve the urban quality of life for residents and external users.

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This master thesis is intended to perform an exploratory approach for the potential to Public-Private Partnerships as a tool for advanced collaboration between businesses and the cooperation system in the specific context of humanitarian action. It intends to conduct a case study analysis of representative interactions between the public and private actors in the humanitarian aid, and in conjunction with a profound revision of the existing literature, creates a set of conclusions and recommendations that can serve as a prototype for possible inclusion guide the private sector in humanitarian action through new paradigms that go beyond the classical donor-recipient model.

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Cloud computing and, more particularly, private IaaS, is seen as a mature technology with a myriad solutions tochoose from. However, this disparity of solutions and products has instilled in potential adopters the fear of vendor and data lock-in. Several competing and incompatible interfaces and management styles have given even more voice to these fears. On top of this, cloud users might want to work with several solutions at the same time, an integration that is difficult to achieve in practice. In this paper, we propose a management architecture that tries to tackle these problems; it offers a common way of managing several cloud solutions, and an interface that can be tailored to the needs of the user. This management architecture is designed in a modular way, and using a generic information model. We have validated our approach through the implementation of the components needed for this architecture to support a sample private IaaS solution: OpenStack

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The size and complexity of cloud environments make them prone to failures. The traditional approach to achieve a high dependability for these systems relies on constant monitoring. However, this method is purely reactive. A more proactive approach is provided by online failure prediction (OFP) techniques. In this paper, we describe a OFP system for private IaaS platforms, currently under development, that combines di_erent types of data input, including monitoring information, event logs, and failure data. In addition, this system operates at both the physical and virtual planes of the cloud, taking into account the relationships between nodes and failure propagation mechanisms that are unique to cloud environments.

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On December 17 came into force on community standard marine fuels. Bunker prices are expected to increase, recent statistics support this argument and the difference between the high sulphur (HS) and the low sulphur (LS) marine bunkers will be sustained. Considering also the price difference between the basis-market of Rotterdam with the rest European ports, the expected bunker prices will be higher in the Mediterranean. This paper begins with a review of the current situation in ECAS areas, highlighting the rules to be implemented shortly. The aim of the paper is known the current situation bunkering determine the estimated short term in Spain from world fleet.

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Since the mid 80ies the Trans ‐European Transport Network (TEN‐T) policy has been setting the framework for the development of infrastructure for the smooth functioning of the internal market within the European Union (EU). Public Private Partnerships (PPPs) have always been regarded by the EU as a key instrument to promote the TEN‐T.

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OUTLINE: • Introduction • Experimental Setup • Experimental Procedure • Experimental Results - Surface Roughness - Residual Stresses - Friction - Wear - EDX • Conclusions

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Cloud computing and, more particularly, private IaaS, is seen as a mature technol- ogy with a myriad solutions to choose from. However, this disparity of solutions and products has instilled in potential adopters the fear of vendor and data lock- in. Several competing and incompatible interfaces and management styles have increased even more these fears. On top of this, cloud users might want to work with several solutions at the same time, an integration that is difficult to achieve in practice. In this Master Thesis I propose a management architecture that tries to solve these problems; it provides a generalized control mechanism for several cloud infrastructures, and an interface that can meet the requirements of the users. This management architecture is designed in a modular way, and using a generic infor- mation model. I have validated the approach through the implementation of the components needed for this architecture to support a sample private IaaS solution: OpenStack.

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This paper describes a theoretical model based primarily on transaction costs, for comparing the various tendering mechanisms used for transportation Public-Private Partnership (PPP) projects. In particular, the model contrasts negotiated procedures with the open procedure, as defined by the current European Union legislation on public tendering. The model includes both ex ante transaction costs (borne during the tendering stage) and ex post transaction costs (such as enforcement costs, re-negotiation costs, and costs arising from litigation between partners), explaining the trade-off between them. Generally speaking, it is assumed that the open procedure implies lower transaction costs ex ante, while the negotiated procedure reduces the probability of the appearance of new contingencies not foreseen in the contract, hence diminishing the expected value of transaction costs ex post. Therefore, the balance between ex ante and ex post transaction costs is the main criterion for deciding whether the open or negotiated procedure would be optimal. Notwithstanding, empirical evidence currently exists only on ex ante transaction costs in transportation infrastructure projects. This evidence has shown a relevant difference between the two procedures as far as ex ante costs are concerned, favouring the open procedure. The model developed in this paper also demonstrates that a larger degree of complexity in a contract does not unequivocally favour the use of a negotiated procedure. Only in those cases dealing with very innovative projects, where important dimensions of the quality of the asset or service are not verifiable, may we observe an advantage in favour of the negotiated procedure. The bottom line is that we find it difficult to justify the employment of negotiated procedures in most transportation PPP contracts, especially in the field of roads. Nevertheless, the field remains open for future empirical work and research on the levels of transaction costs borne ex post in PPP contracts, as well as on the probabilities of such costs appearing under any of the procurement procedures.

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The current deficit situation of the Spanish airport system suggests the need to manage this in a more efficient and profitable way. One of the possible options is through private management and being able to do this through Public Private Partnerships (PPP). This study analyzes the situation of the sector and its economic importance and the different possibilities for introducing private management in a public company, specifying the situation in the case of airports, presenting the advantages and disadvantages of these possibilities, and aiming at results obtained in other places where it has been applied. It is proposed that the ideal model for the introduction of private management would be through PPP models tailored to each airport, but having common characteristics according to the group they belong to. Finally, we observe that not all airports are commercially attractive, so that the PPP concept does not apply to all of them. In some cases even the operability itself is not viable at all, and that should be considered separately in order to avoid creating a private monopoly while trying to enhance competition among them.