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1 to 50 of 101 results
  • Competitive transit network design in cities with radial street patterns

     Badia, Hugo; Estrada Romeu, Miguel Angel; Robuste Anton, Francesc
    Transportation research. Part B, methodological
    Date of publication: 2014-01
    Journal article

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    This paper presents a reformulation of the hybrid model developed by Daganzo (2010) to extend its applicability to a greater number of cities, especially those characterized by a radial street pattern. The new transit network structure is also composed of two types of schemes: radial/circular in the central area and hub and spoke in the periphery. This analytical model defines the optimal network layout through minimizing its objective function, which is composed of agency and user costs. Its decision variables are central area size, headway, line spacing, and stop spacing. In this reformulation, stops with single coverage, those only served by one line, are introduced in the hybrid model to improve spatial accessibility to avoid an increase in agency investment. This model is a tool to design competitive transit systems topologically characterized by simple schemes adapted to the urban structure and concentrated transit flows, and also operatively by high frequencies and speeds. Ultimately, all this allows for easy use and management of transit networks. The model¿s robustness with regard to input parameters and decision variables reinforces its results and estimates what implementations on real road networks would be like. It presents coherent behavior regarding real-world standards, where high, concentrated and temporally well distributed demands lead to more efficient and effective transit systems. High performance bus (HPB) is the transport technology used throughout this paper because, as has been proved in this paper, it is the best transit mode in urban areas for a wide range of demand values. Main system characteristics have been obtained such as central areas greater than a 25% of the city, low headways of around 2 min, high commercial speeds ranges between 14 and 17 km/h, and suitable spatial accessibility, where stop spacing moves between 350 and 550 m.

  • Assessment of taxi sector efficiency and profitability based on continuous monitoring and methodology to review fares

     Amat Bertran, Carles; Estrada Romeu, Miguel Angel; Ortigosa Marin, Javier
    Transportation Research Board Annual Meeting
    Presentation's date: 2014-01-15
    Presentation of work at congresses

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    The taxi sector presents many challenges to adequately serve the demand while maximising efficiency and profitability and minimising externalities. Many authors have dealt with the `taxi industry¿ by modelling and forecasting its activity, usually using limited, incomplete or no trustable data to validate their model. The present paper tackles a different point of view. The applied methodology is based in the continuous monitoring of a sample of taxis that provide information recorded by the taximeter about their real activity. Taximeter data allows the definition of a wide series of representative and relevant Key Performance Indicators (KPIs) with which characterize the taxi activity. This paper focuses on the analysis of efficiency and profitability using KPIs. Thus, indicators firstly diagnose the system revealing its (in)efficiencies and whether or not is profitable. While studying profitability, the concept of the reasonable profit (RP) is presented to ensure welfare to the taxi driver. Indicators also represent an assessment tool to evaluate improvement measures and they constitute a powerful support for the decision making. In this sense, a methodology for the annual review of fares is developed introducing the concept of the RP. KPIs are applied in Barcelona, where they proof a demand-supply imbalance: since 2008 supply has increased significantly and demand has diminished; consequently, productivity and profitability have decreased considerably. Hence, KPIs reveal the inefficiencies of the Barcelona taxi system and demonstrate that its profitability is at risk.

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    Redesign and implementation of the urban bus network of Lleida (Spain)  Open access

     Trapote Barreira, Cesar; Robuste Anton, Francesc; Badia Rodriguez, Hugo; Estrada Romeu, Miguel Angel
    Congreso Panamericano de Ingeniería del Tráfico, Transporte y Logística
    Presentation's date: 2014-06-11
    Presentation of work at congresses

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    We present a strategy to improve bus service in urban networks that gives equal or better transit service and saves public resources: a win-win strategy. It consists on changing from ¿direct lines¿ to mobility centers from each quarter of the city to a bidimensional ¿network structure¿ and from ¿schedule based¿ management to ¿frequency based¿ management. The implementation in Lleida, a 140,000 inhabitant city of Spain, has proven that it is possible to save 15% of the resources providing equal or better door-to-door service, but a final fine-tuning has found the proper equilibrium between ¿network structure¿ and ¿direct lines¿ to better fit the users¿ perception.

    We present a strategy to improve bus service in urban networks that gives equal or better transit service and saves public resources: a win-win strategy. It consists on changing from “direct lines” to mobility centers from each quarter of the city to a bidimensional “network structure” and from “schedule based” management to “frequency based” management. The implementation in Lleida, a 140,000 inhabitant city of Spain, has proven that it is possible to save 15% of the resources providing equal or better door-to-door service, but a final fine-tuning has found the proper equilibrium between “network structure” and “direct lines” to better fit the users’ perception.

  • Agent based modeling for simulation of taxi services

     Salanova Grau, Josep Maria; Estrada Romeu, Miguel Angel; Mitsakis, Evangelos; Stamos, Iraklis
    Journal of Traffic and Logistics Engineering
    Date of publication: 2013-12
    Journal article

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    This paper presents an agent based model for simulating taxi services in urban areas. The three operation modes (hailing, stand and dispatching) are modeled and tested in the Sioux Falls network. Taxi models presented in the literature are divided into aggregated and equilibrium models, with a very small presence of simulation models. The different programmed modules are presented together with the behavior rules of the agents. Performance indicators are calculated for each operation mode and compared in terms of driver earnings, user cost and vacant versus occupied time.

  • Modeling of taxi cab fleets in urban environment

     Salanova Grau, Josep Maria
    Defense's date: 2013-12-19
    Universitat Politècnica de Catalunya
    Theses

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    Els taxis són un mode de transport necessari per satisfer les necessitats de la població relacionades amb la mobilitat. L'impacte del mercat del taxi a la vida quotidiana és molt important, tant des del punt de vista econòmic (per exemple, els salaris dels taxistes) com social (per exemple, la congestió o la satisfacció de la demanda de desplaçaments). S¿han desenvolupat diversos models amb l'objectiu de quantificar els impactes i avaluar el rendiment del sector del taxi, inicialment des d'un punt de vista agregat i econòmic i, recentment, des d'un punt de vista operacional i més realista.L'objectiu principal d'aquesta tesi és el de desenvolupar models d¿estudi dels serveis oferts pel sector del taxi, fent èmfasi en el dimensionament de la flota òptima de taxis necessària per satisfer la demanda oferint un temps d¿espera raonable per als clients i assegurant al mateix temps una mínima rendibilitat als taxistes. Per a aquest propòsit, s'han desenvolupat dos models, un econòmic analític i un de simulació basada en agents. El primer model és capaç d'analitzar el mercat dels taxis des d'un punt de vista macroscòpic mitjançant l¿ús de valors mitjans representatius de tota la regió per obtenir el nombre òptim de taxis que satisfarà les necessitats de la població amb uns costos unitaris mínims, obtenint també el temps d'espera relacionat a aquesta flota òptima. El segon model és capaç de reproduir les característiques operacionals del sector del taxi en detall, simulant viatges en taxi a la xarxa viaria i enregistrant tots els indicadors de rendiment relacionats amb l¿eficiència operacional del sector del taxi. S'utilitzen dades reals de la ciutat de Barcelona per al calibratge dels models proposats i per a l'obtenció dels resultats de l'aplicació d¿ambdós models al sector del taxi de la ciutat de Barcelona.Els dos models desenvolupats es complementen perfectament, la seva combinació pot ser una eina valuosa per als responsables de la regulació del sector del taxi, ja que els permetrà analitzar els serveis del taxi i prendre les decisions correctes per millorar els servies oferts. Al mateix temps, els problemes operacionals poden ser analitzats en detall durant la fase de disseny de la política de taxis, ja que tots els actors estàn inclosos dins dels models i es tenen en compte alhora d'optimitzar el rendiment del sector del taxi. Els models s'utilitzen per analitzar l'impacte de les polítiques tarifaries en el mercat del taxi. També es te en compte la política de torns, per la qual s¿ha plantejat un problema d'optimització que fa coincidir el nombre òptim de vehicles obtingut dels models amb el real proporcionat per la política de torns, que és la més comú a tot el món .Es presenten rangs òptims de demanda per als tres modes operatius. Els sistemes de taxi basats en centraletes telefòniques es mostren més eficients per baixes concentracions de demanda, mentre que els sistemes de taxi al carrer presenten menors costos unitaris per altes concentracions de demanda. Els models agregats tendeixen a subestimar els costos, tant dels clients com del sistema entre el 15% i el 30% si la distribució de la demanda és uniforme. Per demandes no uniformes, els models agregats sobreestimen els costos entre un 20% i 300%, depenent del valor de GINI de la distribució de la demanda.

  • Zero Emission bUs Systems

     Estrada Romeu, Miguel Angel
    Participation in a competitive project

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  • Optimal length of transit network with traffic performance microsimulation: application to Barcelona, Spain

     Estrada Romeu, Miguel Angel; Robuste Anton, Francesc; Badia Rodriguez, Hugo; Amat, Jordi; Barcelo Bugeda, Jaime
    Transportation research record
    Date of publication: 2012
    Journal article

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  • The design of interurban bus networks in city centers

     Roca-Riu, Mireia; Estrada Romeu, Miguel Angel; Trapote Barreira, César
    Transportation research. Part A, general
    Date of publication: 2012-10
    Journal article

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  • An evaluation of urban consolidation centers through logistics systems analysis in circumstances where companies have equal market shares

     Roca Riu, Mireia; Estrada Romeu, Miguel Angel
    Procedia - Social and behavioral sciences
    Date of publication: 2012
    Journal article

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  • A mathematical approach and review of the modeling of taxi services

     Estrada Romeu, Miguel Angel; Salanova Grau, Josep Maria
    European Symposium on Quantitative Methods in Transportation Systems
    Presentation's date: 2012-09
    Presentation of work at congresses

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    This paper presents a mathematical model for the estimation of the key performance indicators of the taxi markets in urban areas. These key parameters are basically the demand and supply for taxi services, the waiting time of users and the cost of the different involved actors. The identified actors are the drivers, the taxi users and the city, represented by the other drivers and the inhabitants. Optimum values for the taxi supply are obtained from the mathematical formulations depending on the demand level and the size of the city, presenting the users waiting time and the unitary system costs related to this optimum fleet size. The model is applied to two modes of operations, hailing and dispatching market. Conclusions are drawn for the best type of market for each demand level and city size.

    This paper presents a mathematical model for the estimation of the key performance indicators of the taxi markets in urban areas. These key parameters are basically the demand and supply for taxi services, the waiting time of users and the cost of the different involved actors. The identified actors are the drivers, the taxi users and the city, represented by the other drivers and the inhabitants. Optimum values for the taxi supply are obtained from the mathematical formulations depending on the demand level and the size of the city, presenting the users waiting time and the unitary system costs related to this optimum fleet size. The model is applied to two modes of operations, hailing and dispatching market. Conclusions are drawn for the best type of market for each demand level and city size.

  • On the optimal length of the transit network with traffic performance microsimulation: application to Barcelona

     Estrada Romeu, Miguel Angel; Robuste Anton, Francesc; Amat, Jordi; Badia, Hugo; Barcelo Bugeda, Jaime
    Transportation Research Board Annual Meeting
    Presentation's date: 2012-01-25
    Presentation of work at congresses

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    This paper examines the design of high performance transit network that minimizes the transit agency costs, the time of transit users in the system and the travel time of car users. Surface transit services need segregated lanes to achieve a target cruising speed, so that the transit network length has a significant impact on the traffic performance. This effect has been modeled in this paper by the Macroscopic Fundamental Diagram (MFD). The optimization process encompasses two different approaches. First, an analytic model defines the optimal layout of surface transit networks according to the time headway, stop spacing, line spacing and network size variables. Then, the average travel time of the traffic network is evaluated by the use of the MFD curve corresponding to the former transit network length. The full methodology has been implemented in the city of Barcelona. The calibration of MFD in its central district has been done by means of traffic microsimulation runs. The social optimum number of corridors is 15, somewhat smaller than the optimization which does not consider traffic (23).

  • Estimación de la longitud óptima de la red de autobuses considerando los efectos sobre el vehículo privado

     Amat, Jordi; Estrada Romeu, Miguel Angel; Robuste Anton, Francesc; Badia, Hugo
    Congreso de Ingeniería del Transporte
    Presentation's date: 2012-06-22
    Presentation of work at congresses

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    El presente trabajo trata la optimización del diseño de redes de autobús de altas prestaciones teniendo en cuenta los costes de los usuarios y el operador del bus junto con los costes del vehículo privado. Investigaciones recientes (Daganzo 2010, Estrada et al. 2011) formulan las prestaciones de los usuarios y los costes del operador de una red de altas prestaciones en ciudades compactas. Dichas prestaciones se consiguen segregando las líneas de transporte público, utilizando buses de alta capacidad, mayor espaciamiento entre paradas y con intervalos de paso bajos en hora punta. La implementación de la red de autobuses genera una disminución del espacio viario disponible para el vehículo privado que conllevará el incremento de los tiempos de viaje de la red vial. En consecuencia, en el presente trabajo se incluye el coste asociado al vehículo privado dentro de la función objetivo de costes. Dicho coste se formula a partir del diagrama fundamental macroscópico (Geroliminis y Daganzo, 2008) que se considera variable según el número de corredores de la red de altas prestaciones. En su aplicación a la ciudad de Barcelona, la inclusión del vehículo privado en la función objetivo resulta en una red óptima de 15 corredores de altas prestaciones. Este valor se sitúa entre el valor óptimo sin restricciones de 23 corredores presentado por Estrada et al. (2011) y los 11 corredores propuestos por la administración pensados para no afectar en exceso al vehículo privado.

  • Planning a freight network with hub and spoke strategies

     Roca Riu, Mireia; Ortigosa Marin, Javier; Estrada Romeu, Miguel Angel
    Transportation Research Board Annual Meeting
    Presentation's date: 2012-01-23
    Presentation of work at congresses

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    The location of freight terminals in a territory is a key factor for their performance and competitiveness. Nowadays, several factors led to the implantation of a freight terminal in an area and then different possible micro-locations are evaluated. Micro-location considers several pieces of land in the same region depending on prices, availability, and transport connections. However, the macro-location is not normally considered in current analysis, that is to say, that flows among regions are not considered before deciding where the terminal should be located. In this article, we present the development of a methodology to locate strategic areas for freight terminals taking into account the interaction of freight flows. The methodology is based on Hub and Spoke networks which are extended to accommodate a new network structure: the arborescent allocation formulation. The new structure proves to be suitable for freight network, providing savings but not being extra rigid. The methodology presents an optimal configuration of freight terminals according to the goods flow, transport costs and node connections. A case study is devoted to the Spanish network.

  • Indicadores de productividad y revisión de tarifas en el sector del taxi

     Amat Bertran, Carles; Estrada Romeu, Miguel Angel; Thorson Bofarull, Leif
    Congreso de Ingeniería del Transporte
    Presentation's date: 2012-06-21
    Presentation of work at congresses

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  • Design and implementation of efficient transit networks: procedure, case study and validity test

     Estrada Romeu, Miguel Angel; Roca Riu, Mireia; Badia, Hugo; Robuste Anton, Francesc; Daganzo, Carlos F.
    Procedia - Social and behavioral sciences
    Date of publication: 2011
    Journal article

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  • A review of the modeling of taxi services

     Salanova Grau, Josep Maria; Estrada Romeu, Miguel Angel; Aifadopoulou, G; Mitsakis, Evangelos
    Procedia - Social and behavioral sciences
    Date of publication: 2011
    Journal article

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  • Design and implementation of efficient transit networks: Procedure, case study and validity test

     Estrada Romeu, Miguel Angel; Roca Riu, Mireia; Badia, Hugo; Daganzo, Carlos F.; Robuste Anton, Francesc
    Transportation research. Part A, policy and practice
    Date of publication: 2011-11-11
    Journal article

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  • Junts! Els reptes del transport públic a Barcelona

     Turro Calvet, Mateo; Robuste Anton, Francesc; Estrada Romeu, Miguel Angel
    Date of publication: 2011
    Book chapter

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  • Assessment of the public transportation supply in a local level

     Campos Cacheda, Jose Magin; Alsina, Guillem; Estrada Romeu, Miguel Angel
    Transportation Research Board Annual Meeting
    Presentation's date: 2011-01-19
    Presentation of work at congresses

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    This article presents new methodology for assessing the quality provided by urban surface transit systems in terms of comfort, speed and coverage. A set of robust indicators are presented to measure how transit supply serves the multimodal chain of users (access, waiting and in-vehicle time) as well as the performance of the transit system. These measures are summarized in a unique indicator that accounts for the quality of the global service. The latter may be a useful tool to redefine existing transit systems (routes, frequencies or capacity allocation) to any changes in the spatial or time distribution of demand. This methodology has been implemented to the local bus network in Barcelona (Spain) in order to identify the necessary readjustments between transit supply and demand.

  • Efficient layout and management of urban bus networks

     Estrada Romeu, Miguel Angel
    Truck and Bus World Forum
    Presentation's date: 2011-12-01
    Presentation of work at congresses

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  • Projecte ¿Retbus¿: el bus del futur a Barcelona

     Estrada Romeu, Miguel Angel
    European Passenger Federation Annual Congress
    Presentation's date: 2011-03-12
    Presentation of work at congresses

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  • Tandem bus stop capacity

     Estrada Romeu, Miguel Angel; Ortigosa Marin, Javier; Robuste Anton, Francesc
    Transportation Research Board Annual Meeting
    Presentation's date: 2011-01
    Presentation of work at congresses

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    Bus stops represent a key bottleneck that produces significant delays in travel times. In major cities, the width of streets is constrained by sidewalks and buildings. In this context, adding on-street loading areas in series is a valid method to increase bus stop capacity. A tandem bus stop is a linear bus stop with two loading areas on a dedicated bus lane where buses serve depending on the sequence in which they arrive at the stop since overtaking is not allowed. The objective of this paper is to provide an analytical methodology to help city planners to choose between conventional and tandem bus stops. This study focuses on the capacity gain of a tandem bus stop in the case where there are buses waiting in line. Current studies are based on simulation results only for particular cases. The model is applied to Barcelona, Spain, where the dwell time is described by a log-normal distribution according to the available empirical data. The results obtained in this paper indicate that a capacity gain of 30 to 70% can be achieved, which allows for substantial commercial speed increasing. If buses spend more time at the service position and the variability is low, the gain is greater. Our results suggest including in the Transit Capacity and Quality of Service Manual a more detailed description of the behavior of urban tandem bus stops, where the “effective number of berths” concept should be considered a variable (instead of constant) that depends on the dwell time characteristics.

  • STRAIGHTSOL Strategies and measures for smarter urban freight solutions

     Estrada Romeu, Miguel Angel; Andersen, Jardar
    Participation in a competitive project

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  • MEDUSA Microplataformas eficientes para una distribución urbana de mercancías sostenible

     Estrada Romeu, Miguel Angel
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    Effect of variable bus speeds on bus network design  Open access

     Foletta, Nicole; Estrada Romeu, Miguel Angel; Roca-Riu, Mireia; Martí, P
    Journal of public transportation
    Date of publication: 2010
    Journal article

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    This article provides a methodology for solving the bus network design problem, covering network design and frequency setting and taking into consideration that commercial speeds of buses vary depending on the aggregated frequency of buses on each corridor. This methodology, referred to as Variable Speed Methodology, uses a variation of an algorithm proposed by Baaj and Mahmassani that assumes speeds remain constant (denoted Fixed Speed Methodology). Both methodologies were applied to the street network of Barcelona. Outputs were compared, and it was found that the Variable Speed Methodology produces a bus network with faster average travel speeds, shorter travel times, smaller fleet size, less route kilometer, and fewer buses per link while still serving the same level of demand. These results demonstrate that taking variability of bus speeds into consideration when performing route generation and frequency setting can significantly improve the performance of the bus network produced.

  • New modifications to bus network design methodology

     Foletta, Nicole; Estrada Romeu, Miguel Angel; Roca Riu, Mireia; Martí, Pere
    Transportation research record
    Date of publication: 2010
    Journal article

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  • Transport, mobilitat i logística

     Robuste Anton, Francesc; Estrada Romeu, Miguel Angel
    Date of publication: 2010
    Book chapter

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  • New modifications to bus network design methodology

     Foletta, Nicole; Estrada Romeu, Miguel Angel; Roca-Riu, Mireia; Martí, Pere
    Transportation Research Board Annual Meeting
    Presentation's date: 2010-01
    Presentation of work at congresses

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  • Modelo de localización de zonas estratégicas para actividades logísticas

     Ortigosa Marin, Javier; Estrada Romeu, Miguel Angel; Campos Cacheda, Jose Magin; Roca-Riu, Mireia
    Congreso de Ingeniería del Transporte
    Presentation's date: 2010-07-08
    Presentation of work at congresses

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  • Diseño de redes de transporte público en superficie considerando tiempos de circulación variables según congestión

     Roca-Riu, Mireia; Estrada Romeu, Miguel Angel; Foletta, Nicole; Martí, Pere
    Congreso de Ingeniería del Transporte
    Presentation's date: 2010-07-08
    Presentation of work at congresses

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  • Diseño de una red de autobuses de altas prestaciones mediante aproximaciones continuas

     Estrada Romeu, Miguel Angel; Cuscurita royo, Demelsa; Roca-Riu, Mireia; Ortigosa Marin, Javier; Robuste Anton, Francesc
    Congreso de Ingeniería del Transporte
    Presentation's date: 2010-07-07
    Presentation of work at congresses

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  • MEDIMEC - Modelos eficientes de distribución de mercancías por carretera

     Estrada Romeu, Miguel Angel; Campos Cacheda, Jose Magin
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  • IX Congreso de Ingeniería del Transporte. Premio al mejor artículo de Transporte Público

     Estrada Romeu, Miguel Angel; Cuscurita royo, Demelsa; Roca-Riu, Mireia; Ortigosa Marin, Javier; Robuste Anton, Francesc
    Award or recognition

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  • Improving bus travel times with passive traffic signal coordination

     Estrada Romeu, Miguel Angel; Trapote Barreira, Cesar; Roca Riu, Mireia; Robuste Anton, Francesc
    Transportation research record
    Date of publication: 2009
    Journal article

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  • Optimización de envios en la red troncal de empresas de carga fraccionada

     Estrada Romeu, Miguel Angel
    Guía Logisnet
    Date of publication: 2009
    Journal article

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  • Long-haul shipment optimization for less-than-truckload carriers

     Estrada Romeu, Miguel Angel; Robuste Anton, Francesc
    Transportation research record
    Date of publication: 2009
    Journal article

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  • Innovación en la DUM y en la gestión de servicios urbanos

     Estrada Romeu, Miguel Angel
    Congreso Nacional de Movilidad y Distribución Urbana Sostenible
    Presentation's date: 2009-06-30
    Presentation of work at congresses

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  • Long-haul shipment optimization for less-than-truckload carriers

     Estrada Romeu, Miguel Angel; Robuste Anton, Francesc
    Transportation Research Board Annual Meeting
    Presentation's date: 2009-01
    Presentation of work at congresses

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    Less-than-truckload (LTL) carriers supply freight transportation services for small parcel shipments. These companies consolidate multiple shipments in vehicles to guarantee the efficiency of the system. A method for LTL carriers is presented to solve the long-haul routing design problem with capacitated distribution centers and time-constrained shipments. The method uses direct, hub-and-spoke, and stopover strategies to allocate shipments in the set of routes. The resolution method is based on a tabu search algorithm. The search process in the solution domain is performed dynamically with four possible perturbations. The results obtained in a set of test problems demonstrate that the restart parameters play a significant role in the efficiency of the algorithm. Implementation of this computational technique in the long-haul operations network of the largest carrier in Spain reduced transportation costs by 6%.

  • REPLICA ¿ Red española de plataformas logísticas intermodales para la mejora de la competitividad y la sostenibilidad ambiental del transporte de mercancías

     Robuste Anton, Francesc; Thorson Bofarull, Leif; Campos Cacheda, Jose Magin; Estrada Romeu, Miguel Angel; Sauri Marchan, Sergi
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  • Modelos eficientes de distribución de mercancías por carretera

     Estrada Romeu, Miguel Angel; Robuste Anton, Francesc; Thorson Bofarull, Leif
    Participation in a competitive project

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  • Improving bus travel times with passive traffic signal coordination

     Estrada Romeu, Miguel Angel; Trapote Barreira, Cesar; Roca Riu, Mireia; Robuste Anton, Francesc
    Transportation Research Board Annual Meeting
    Presentation's date: 2009-01-12
    Presentation of work at congresses

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    A simulation optimization model is outlined: traffic signal offsets in intersections are calculated to minimize the travel time of bus users in an urban network. The model considers a passive signal priority system and restricts the maximal incremental delay caused to car users. The simulation tool is able to trace discrete trajectories of both buses and cars in a network. It also evaluates potential perturbations that may cause time variations for average performance. Moreover, the optimization tool is based on evolutionary algorithms. The results of applying the traffic signal coordination model to a set of small trial networks are given. It is proved that the algorithm is able to design a sequence of signal offsets that reduces bus travel times by an 8.5% rate in a real network while maintaining the incremental car delay below 5%.

  • Semiconducting P3HT microstructures: fibres and tubes obtained from macroporous silicon template

     Palacios, R; Formentin, P; Todorov Trifonov, Trifon; Estrada Romeu, Miguel Angel; Alcubilla Gonzalez, Ramon; Pallares, J; Marsal, L F
    Physica status solidi. Rapid research letters
    Date of publication: 2008-10
    Journal article

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  • Exploring the link between small-scale hydrodynamic properties and harmful phytoplankton blooms in the Ebro Delta

     Artigas, M L; Quesada López, Rubén; Berdalet, E; Piera Fernandez, Jaume; Fernández-Tejedor, M; Diogène, J; Estrada Romeu, Miguel Angel
    European Geosciences Union General Assembly
    Presentation's date: 2008-04-13
    Presentation of work at congresses

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  • Tecnologías ecológicas para el transporte urbano

     Robuste Anton, Francesc; Estrada Romeu, Miguel Angel; Thorson Bofarull, Leif
    Participation in a competitive project

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  • Análisis de mejora de la accesibilidad y eficiencia de las operaciones en nodos de intercambio modal y plataformas logísticas. Aplicación a casos concretos

     Robuste Anton, Francesc; Estrada Romeu, Miguel Angel; Thorson Bofarull, Leif
    Participation in a competitive project

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  • Optimización de la coordinación intermodal mediante la modelización del comportamiento del usuario

     Estrada Romeu, Miguel Angel; Robuste Anton, Francesc; Trapote Barreira, Cesar; Thorson Bofarull, Leif
    Participation in a competitive project

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  • BCN R+D. Disseny d'una xarxa eficient d'autobusos per a Barcelona. Fase 2 Millora de les velocitats comercials

     Thorson Bofarull, Leif; Estrada Romeu, Miguel Angel; Trapote Barreira, Cesar
    Date: 2008-10
    Report

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