973 resultados para Travel time.
Resumo:
The City of Madrid is putting into operation Intermodal Exchange Stations (IESs) to make connections between urban and suburban transportation modes easier for users of public transportation. The purpose of this article is to evaluate the actual effects that the implementation of IESs in the City of Madrid has on the affected stakeholders: users, public transportation operators, infrastructure managers, the government, the abutters and other citizens. We develop a methodology intended to help assess the welfare gains and losses for each stakeholder. Then we apply this methodology to the case study of the Avenida de América IES in the city of Madrid. We found that it is indeed possible to arrive at win–win solutions for the funding of urban transportation infrastructure, as long as the cost-benefit ratio of the project is high enough. Commuters save travel time. Bus companies diminish their costs of operation. The abutters gain in quality of life. The private operator of the infrastructure makes a fair profit. And the government is able to promote these infrastructure facilities without spending more of its scarce budgetary resources.
Resumo:
Travel time savings, better quality of the supplied services, greater comfort for the users, and improved accessibility are the main factors of success of High Speed Rail(HSR)links. This paper presents the results from a revealed and stated preference survey conducted to both HSR and air transport users in the Madrid Barcelona corridor. The data gathered from the stated preference survey was used to calibrate a modal choice model aiming at explaining competition between HSR and air transportation in the corridor. From the model, the authors obtain that prices and service frequency are the most important variables to compete with the other mode. In addition, they found that check-in and security controls at the airport are a crucial variable for the users in their modal choice. Other policies, such as the improvement of parking facilities at the train stations, play a secondary role.
Resumo:
In this paper some mathematical programming models are exposed in order to set the number of services on a specified system of bus lines, which are intended to assist high demand levels which may arise because of the disruption of Rapid Transit services or during the celebration of massive events. By means of this model two types of basic magnitudes can be determined, basically: a) the number of bus units assigned to each line and b) the number of services that should be assigned to those units. In these models, passenger flow assignment to lines can be considered of the system optimum type, in the sense that the assignment of units and of services is carried out minimizing a linear combination of operation costs and total travel time of users. The models consider delays experienced by buses as a consequence of the get in/out of the passengers, queueing at stations and the delays that passengers experience waiting at the stations. For the case of a congested strategy based user optimal passenger assignment model with strict capacities on the bus lines, the use of the method of successive averages is shown.
Resumo:
En algunos países, como por ejemplo España, es común que entre un origen y un destino existan dos carreteras paralelas en las que existen ciertas diferencias. La más importante es que una de las vías es una autopista que ofrece a los usuarios una mayor comodidad y un menor tiempo de viaje a cambio del pago de un peaje, el cual no es necesario abonar en la carretera convencional paralela. Así, el problema de la tarificación vial ha sido estudiado en diversas ocasiones. Existe un amplio consenso en que para lograr el máximo bienestar social, los usuarios deben internalizar las externalidades que producen y no perciben a través de un peaje. Sin embargo, dicho peaje puede perjudicar a los usuarios con bajos ingresos. Dependiendo del objetivo (por ejemplo, maximizar el bienestar, maximizar la equidad social, la amortización de la construcción de la carretera, etc) el peaje óptimo podría variar sustancialmente. La literatura académica acerca de los peajes, la eficiencia y la equidad es vasta y diversa. Sin embargo, hemos encontrado una deficiencia en dicha literatura sobre el peaje óptimo, en corredores donde una carretera y una autopista con diferentes características de calidad compiten para capturar el tráfico. Particularmente no se ha encontrado ninguna investigación acerca del establecimiento del peaje que maximice el bienestar social o la equidad para distintas distribuciones del valor del tiempo de viaje (VTT), caracterizadas por su media y varianza. Por ello, el principal objetivo de la investigación es estimar la influencia que tiene la distribución de la renta de una sociedad sobre el peaje óptimo. La presente tesis doctoral trata de obtener, por medio de una metodología robusta, las diferentes políticas de peajes que los planificadores de transporte deberían llevar a cabo según la riqueza y cohesión social de los potenciales usuarios del corredor, la demanda y el objetivo que se busque con dicha tarificación, esto es, maximizar el bienestar social o la equidad. Adicionalmente también se obtienen los peajes óptimos dependiendo de si el corredor se encuentra totalmente tarificado o únicamente se debe pagar un peaje por circular en la autopista. In some countries, such as Spain, it is very common that in the same corridor there are two roads with the same origin and destination but with some differences. The most important contrast is that one is a toll highway which offers a better quality than the parallel road in exchange of a price. The users decide if the price of the toll worth to pay for the advantages offered. The problem of road pricing has been largely studied. It is well acknowledged that in order to achieve the maximum social welfare, users must internalize the externalities they produce and do not perceive through a toll. However, that toll can harm users with low income. Depending on the objective (e.g. maximize welfare, maximize social equity, amortize the construction of the road, etc) the optimal toll might vary substantially. The academic literature about pricing, efficiency and equity is vast and diverse. However, as far as we have found, there is a gap in the literature regarding the optimal price where a road and a highway with different quality characteristics compete for capturing the traffic in a corridor. Particularly we did not find any research estimating the optimal welfare price or the optimal equity price for different Value of Travel Time (VTT) distributions characterized by different VTT average and variance. The objective of the research is to fill this gap. In this research a theoretical model in order to obtain the optimal price in a toll highway that competes for capturing the traffic with a conventional road is developed. This model is done from the welfare and equity perspective and for non‐usual users who decide over the expectation of free flow conditions. The model is finally applied to the variables we want to focus on: average value of travel time (VTT) which is strongly related with income, dispersion of this VTT, different kind of distributions of VTT and traffic levels, from free flow to congestion. Furthermore, we also obtain the optimal tolls with the corridor completely charged or with untolled alternative.
Resumo:
In some countries, such as Spain, it is very common that in the same corridor there are two roads with the same origin and destination but with some differences. The most important contrast is that one is a toll highway which offers a better quality than the parallel road in exchange of a price. The users decide if the price of the toll is worth to pay for the advantages offered. This problem is known as the untolled alternative and it has been largely studied in the academic literature, particularly related to economic efficiency and the optimal welfare toll. However, there is a gap in the literature academic regarding how it affects income distribution to the optimal toll. The main objective of the paper is to fill this gap. In this paper a theoretical model in order to obtain the optimal welfare price in a toll highway that competes for capturing the traffic with a conventional road is developed. This model is done for non-usual users who decide over the expectation of free flow conditions. This model is finally applied to the variables we want to focus on: average value of travel time (VTT) which is strongly related with income, dispersion of this VTT and traffic levels, from free flow to congestion. Derived from the results, we conclude that the higher the average VTT the higher the optimal price, the higher the dispersion of this VTT the lower the optimal price and finally, the more the traffic the higher the optimal toll.
Resumo:
El sector ferroviario ha experimentado en los últimos años un empuje espectacular acaparando las mayores inversiones en construcción de nuevas líneas de alta velocidad. Junto a esta inversión inicial no se debe perder de vista el coste de mantenimiento y gestión de las mismas y para ello es necesario avanzar en el conocimiento de los fenómenos de interacción de la vía y el material móvil. En los nuevos trazados ferroviarios, que hacen del ferrocarril un modo de transporte competitivo, se produce un notable aumento en la velocidad directamente relacionado con la disminución de los tiempos de viaje, provocando por ello elevados esfuerzos dinámicos, lo que exige una elevada calidad de vía para evitar el rápido deterioro de la infraestructura. Resulta primordial controlar y minimizar los costes de mantenimiento que vienen generados por las operaciones de conservación de los parámetros de calidad y seguridad de la vía férrea. Para reducir las cargas dinámicas que actúan sobre la vía deteriorando el estado de la misma, debido a este aumento progresivo de las velocidades, es necesario reducir la rigidez vertical de la vía, pero igualmente este aumento de velocidades hace necesarias elevadas resistecias del emparrillado de vía y mejoras en las plataformas, por lo que es necesario buscar este punto de equilibrio en la elasticidad de la vía y sus componentes. Se analizan las aceleraciones verticales medidas en caja de grasa, identificando la rigidez vertical de la vía a partir de las frecuencias de vibración vertical de las masas no suspendidas, correlacionándola con la infraestructura. Estas aceleraciones verticales se desprenden de dos campañas de medidas llevadas a cabo en la zona de estudio. En estas campañas se colocaron varios acelerómetros en caja de grasa obteniendo un registro de aceleraciones verticales a partir de las cuales se ha obteniendo la variación de la rigidez de vía de unas zonas a otras. Se analiza la rigidez de la vía correlacionándola con las distintas tipologías de vía y viendo la variación del valor de la rigidez a lo largo del trazado ferroviario. Estos cambios se manifiestan cuando se producen cambios en la infraestructura, de obras de tierra a obras de fábrica, ya sean viaductos o túneles. El objeto principal de este trabajo es profundizar en estos cambios de rigidez vertical que se producen, analizando su origen y las causas que los provocan, modelizando el comportamiento de los mismos, para desarrollar metodologías de análisis en cuanto al diseño de la infraestructura. Igualmente se analizan los elementos integrantes de la misma, ahondando en las características intrínsecas de la rigidez vertical global y la rigidez de cada uno de los elementos constituyentes de la sección tipo ferroviaria, en cada una de las secciones características del tramo en estudio. Se determina en este trabajo si se produce y en qué medida, variación longitudinal de la rigidez de vía en el tramo estudiado, en cada una de las secciones características de obra de tierra y obra de fábrica seleccionadas analizando las tendencias de estos cambios y su homogeneidad a lo largo del trazado. Se establece así una nueva metodología para la determinación de la rigidez vertical de la vía a partir de las mediciones de aceleraciones verticales en caja de grasa así como el desarrollo de una aplicación en el entorno de Labview para el análisis de los registros obtenidos. During the last years the railway sector has experienced a spectacular growth, focusing investments in the construction of new high-speed lines. Apart from the first investment the cost of maintaining and managing them has to be considered and this requires more knowledge of the process of interaction between track and rolling stock vehicles. In the new high-speed lines, that make of the railway a competitive mode of transport, there is a significant increase in speed directly related to the shorten in travel time, and that produces high dynamic forces. So, this requires a high quality of the track to avoid quickly deterioration of infrastructure. It is essential to control and minimize maintenance costs generated by maintenance operations to keep the quality and safety parameters of the railway track. Due to this gradual increase of speed, and to reduce the dynamic loads acting on the railway track causing its deterioration, it is necessary to reduce the vertical stiffness of the track, but on the other hand this speed increase requires high resistance of the railway track and improvements of the railway platform, so we must find the balance between the elasticity of the track and its components. Vertical accelerations in axle box are measured and analyzed, identifying the vertical stiffness of the railway track obtained from the vertical vibration frequency of the unsprung masses, correlating with the infrastructure. These vertical accelerations are the result of two measurement campaigns carried out in the study area with the placement of several accelerometers located in the axle box. From these vertical accelerations the variation of the vertical stiffness from one area to another is obtained. The track stiffness is analysed relating with the different types of infrastructure and the change in the value of the stiffness along the railway line. These changes are revealed when changes in infrastructure occurs, for instance; earthworks to bridges or tunnels. The main purpose of this paper is to examine these vertical stiffness changes, analysing its origins and causes, modelling their behaviour, developing analytical methodologies for the design of infrastructure. In this thesis it is also reviewed the different elements of the superstructure, paying special attention to the vertical stiffness of each one. In this study is determined, if it happens and to what extent, the longitudinal variation in the stiffness of track along the railway line studied in every selected section; earthwork, bridges and tunnels. They are also analyzed trends of these changes and homogeneity along the path. This establishes a new method for determining the vertical stiffness of the railway track from the vertical accelerations measured on axle box as well as an application developed in LabView to analyze the recordings obtained.
Resumo:
In some countries, such as Spain, it is very common that in the same corridor there are two roads with the same origin and destination but with some differences. The most important contrast is that one is a toll highway which offers a better quality than the parallel road in exchange of a price. The users decide if the price of the toll is worth paying for the advantages offered. This problem is known as the untolled alternative and it has been largely studied in the academic literature, particularly related to economic efficiency and the optimal welfare toll. However, there is a gap in the academic literature regarding how income distribution affects the optimal toll. The main objective of the paper is to fill this gap. In this paper a theoretical model is developed in order to obtain the optimal welfare price in a toll highway that competes with a conventional road for capturing the traffic. This model is done for non-usual users who decide over the expectation of free flow conditions. This model is finally applied to the variables we want to focus on: average value of travel time (VTT) which is strongly related with income, dispersion of this VTT and traffic levels, from free flow to congestion. Derived from the results, we conclude that the higher the average VTT the higher the optimal price, the higher the dispersion of this VTT the lower the optimal price and finally, the more the traffic the higher the optimal toll