2 research outputs found

    Asignaci贸n de pasajeros y determinaci贸n de frecuencias en redes ferroviarias de tr谩nsito r谩pido

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    Durante las 煤ltimas d茅cadas, la necesidad de movilidad de las personas ha sufrido un incre铆ble aumento, lo que ha provocado una gran demanda diaria de los medios de transporte p煤blico, y como consecuencia, del transporte ferroviario. Adem谩s, tal demanda sigue aumentando d铆a a d铆a en n煤mero y en exigencia, por lo que resulta fundamental lograr una planificaci贸n adecuada del servicio. El presente proyecto, se centra en una de las etapas necesarias para su consecuci贸n, concretamente, tiene el prop贸sito de desarrollar e implementar un modelo de programaci贸n lineal mixta-entera que permita determinar las frecuencias 贸ptimas junto con el resto de variables necesarias para programar cada una de las l铆neas que componen una red de cercan铆as, atendiendo a las caracter铆sticas y exigencias que supone un sistema de transporte como el que se presenta. Adicionalmente, debido a que el modelo se propone para una red compuesta por diferentes l铆neas que cuentan con varias estaciones en com煤n, los pasajeros tendr谩n en la mayor铆a de las ocasiones diferentes opciones o rutas para llegar a un mismo destino, y por ello, surge la necesidad de realizar una asignaci贸n de tr谩nsito que nos permita ver c贸mo se comportan los usuarios dada la red de transporte desarrollada, es decir, que estrategias de viaje seleccionan para llegar al destino deseado. Los dos problemas presentados guardan una estrecha relaci贸n, ya que, en base a las frecuencias establecidas, los pasajeros decidir谩n escoger una ruta u otra, pero al mismo tiempo, en funci贸n del n煤mero de viajeros que utilicen una l铆nea, se establecer谩 una determinada frecuencia de paso. Por lo tanto, se busca alcanzar un equilibrio entre ambos problemas. As铆 mismo, con el objetivo de satisfacer al mismo tiempo tanto a operadores como a pasajeros, se persigue en todo momento la minimizaci贸n de los gastos de tripulaci贸n y de los costes de operaci贸n de los diferentes modelos de tren puestos en marcha, y, junto con ello, minimizar tambi茅n el valor monetario del tiempo total de viaje empleado por los pasajeros para llegar a sus correspondientes destinos, incluyendo no s贸lo el tiempo a bordo del tren, sino tambi茅n tiempos de transferencia y esperas. No obstante, debido a que ambos objetivos son contrapuestos, antes de escoger una soluci贸n final, se muestrear谩 la Frontera de Pareto mediante la resoluci贸n de distintos escenarios, a lo largo de los cuales, se ir谩 variando la ponderaci贸n de cada objetivo. Finalmente, con el prop贸sito de evaluar el desempe帽o del modelo de optimizaci贸n propuesto, se ha realizado su aplicaci贸n pr谩ctica en una parte de la red de cercan铆as de Valencia. Dicha implementaci贸n, ha sido llevada a cabo mediante el lenguaje de programaci贸n Python y, usando a su vez como software de optimizaci贸n, el solver Gurobi.Over the last decades, the people麓s need for mobility has suffered an incredible increase, which has caused a great daily demand for public transport, and consequently, for rail transport. In addition, such demand continues to increase day by day in number and in request, so it is essential to achieve an adequate planning of the service. The present project focuses on one of the necessary stages for its achievement, specifically, it has the purpose of developing a linear programming model that allows determining the optimal frequencies along with the rest of necessary variables to schedule each of the lines that make up a commuter rail network, considering the characteristics and requests of a transport system such as the one presented. Additionally, due to the model is proposed for a network composed of different lines that have in common several stations, in most cases, passengers will have different options or routes to reach the same destination and, because of that, the need arises to make a transit assignment that allows us to see how the users behave given the transport network developed, that is, which travel strategies they select to reach the desired destination. The two problems presented are closely related, since, based on the established frequencies, passengers will choose one route or another, but at the same time, depending on the number of passengers using a line, a certain frequency will be established. Therefore, it is sought to find a balance between both problems. Likewise, with the objective of satisfying both operators and passengers at the same time, it is pursued the minimization of crew costs and operation costs of the different train models put in place, and, along with this, also minimize the monetary value of the total trip time used by passengers to reach their corresponding destinations, including not only on-board travel times, but also transfer times and waiting times. However, since both objectives are opposed, before choosing a final solution, different points of the Pareto Border will be obtained through the resolution of different scenarios in which the weighting of each objective will vary. Finally, with the purpose of evaluating the performance of the proposed linear programming model, it has been carried out its practical application in a part of the Valencia commuter network. This implementation has been carried out using the Python programming language and, using as optimization software, the Gurobi solver.Universidad de Sevilla. Grado en Ingenier铆a de las Tecnolog铆as Industriale

    Generation and Optimization of Train Timetables using Coevolution

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    Train timetabling is a process of assigning suitable arrival and departure times to trains at the stations they visit and at key track junctions. It is desirable that the timetable focusses on passenger preferences and is operationally viable and profitable for the Train Operating Companies (TOCs). Many hard and soft constraints need to be considered relating to the track capacities, set of trains to be run on the network, platform assignments at stations and passenger convenience. In the UK, train timetabling is mainly the responsibility of a single rail infrastructure operator- Network Rail. The UK rail network has a structure that is complex to integrate, which makes it difficult to achieve regularised train timetables that are common in many European countries. With a large number of independent TOCs bidding for slots to operate over limited capacities, the need for an efficient and intelligent computer-aided tool is obvious. This work proposes a Cooperative Coevolutionary Train Timetabling (CCTT) algorithm concerned with the automatic generation of planning timetables, which still demands a high degree of accuracy and optimization for them to be useful
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