Integrating Routing Decisions in Public Transportation Problems PDF Download

Author: Marie E. Schmidt
Publisher: Springer Science & Business Media
ISBN: 1461495660
Category : Business & Economics
Languages : en
Pages : 235

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Book Description
This book treats three planning problems arising in public railway transportation planning: line planning, timetabling, and delay management, with the objective to minimize passengers’ travel time. While many optimization approaches simplify these problems by assuming that passengers’ route choice is independent of the solution, this book focuses on models which take into account that passengers will adapt their travel route to the implemented planning solution. That is, a planning solution and passengers’ routes are determined and evaluated simultaneously. This work is technically deep, with insightful finding regarding complexity and algorithmic approaches to public transportation problems with integrated passenger routing. It is intended for researchers in the fields of mathematics, computer science, or operations research, working in the field of public transportation from an optimization standpoint. It is also ideal for students who want to gain intuition and experience in doing complexity proofs and designing polynomial-time algorithms for network problems. The book models line planning, timetabling and delay management as combined design and routing problems on networks. In a complexity analysis, the border between NP-hard and polynomially solvable problems is illustrated. Based on that, the insights gained are used to develop solution approaches for the considered problems. Besides integer programming formulations, a heuristic method iterating planning and routing step is proposed to solve the problems.

Author: Philine Schiewe
Publisher: Springer Nature
ISBN: 3030462706
Category : Mathematics
Languages : en
Pages : 195

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Book Description
This book is one of the first to include an extensive discussion of integrated public transport planning. In times of growing urban populations and increasing environmental awareness, the importance of optimizing public transport systems is ever-developing. Three different aspects are presented: line planning, timetabling, and vehicle scheduling. Classically, challenges concerning these three aspects of planning are solved sequentially. Due to their high interdependence, the author presents a clear and detailed analysis of innovative, integrated models with accompanied numerical experiments performed to assess, and often support, the benefits of integration. The book will appeal to a wide readership ranging from graduate students to researchers.

Author: Grzegorz Sierpiński
Publisher: Springer Nature
ISBN: 3030717712
Category : Technology & Engineering
Languages : en
Pages : 228

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Book Description
This book contains an abundance of numerical analyses based on significant data sets, illustrating importance of environmentally friendly solutions requiring transport networks to be redesigned or clean zones to be implemented. What kind of steps should be taken to redesign transport network? How to evaluate efficiency or flexibility of transport system and city logistics? What factors can be taken into account in the process of optimizing the functioning of public transport or paid parking zones? How to optimize supply chains (including last mile delivering and routing problem)? Which of the multi-criteria methods should be applied to support decision making processes while tackling problems of global transport systems? Answers to these and many other questions can be found in this book.With regard to the research results discussed and the selected solutions applied, the book entitled "Decision support methods in modern transportation systems and networks" primarily addresses the needs of three target groups: · Scientists and researchers (ITS field) · Local authorities (responsible for the transport systems at the urban and regional level) · Representatives of business (traffic strategy management) and industry (manufacturers of ITS components).

Author: Stefan Helber
Publisher: Springer Science & Business Media
ISBN: 3319007955
Category : Business & Economics
Languages : en
Pages : 577

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Book Description
​This book contains selected papers presented at the "International Annual Conference of the German Operations Research Society (OR2012)" which was held September 4 -7, 2012 at the Leibniz Universität Hannover, Germany. The international conference, which also serves as the annual meeting of the German Operations Research Society (GOR), attracted more than 500 participants from more than 39 countries. Special attention at the conference was given to the three topics "Energy, Markets and Mobility". The OR2012 conference has addressed these topics from an OR perspective, treating them not only in isolation, but also with respect to their numerous and exciting interconnections, such as new energy for new mobility concepts and new market mechanisms for sustainable energy production to name but a few. The proceedings show that this conference topic is an important and promising area to apply Operations Research. The book also contains numerous papers addressing the full scope of fields in Operations Research.

Author: Kaspar Schüpbach
Publisher: Cuvillier Verlag
ISBN: 3736941978
Category : Mathematics
Languages : en
Pages : 138

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Book Description
This thesis investigates the conflict-free routing of vehicles through a track network, a problem frequently encountered in many applications in transportation and logistics. The most common routing approach for conflictfree routing problems in various settings is a sequential one, where requests are greedily served one after the other in a quickest way without interfering with previously routed vehicles. There is a need for a better theoretical understanding as guarantees on the quality of the routings are often missing. Conflict-free vehicle routing also is of inherent interest as a sister problem of the well-studied packet routing problem. In the first part, we present new theoretical results for the case of bidirectional networks. We consider a natural basic model for conflict-free routing of a set of k vehicles. Previously, no efficient algorithm is known with a sublinear (in k) approximation guarantee and without restrictions on the graph topology. We show that the conflict-free vehicle routing problem is hard to solve to optimality even on paths. Building on a sequential routing scheme, we present an algorithm for trees with makespan bounded by O(OPT) + k. Combining this result with ideas known from packet routing, we obtain a first efficient algorithm with sublinear approximation guarantee, namely an O(√k)-approximation. Additionally, a randomized algorithm leading to a makespan of O(polylog(k)) • OPT + k is presented that relies on tree embedding techniques applied to a compacted version of the graph to obtain an approximation guarantee independent of the graph size. The second part is about routing in the Personal Rapid Transit (PRT) application. PRT is a public transportation mode in which small automated vehicles transport passengers on demand. Central control of the vehicles leads to interesting possibilities for optimized routings. Routing in PRT is an online problem where transit requests appear over time and where routing decisions need to be taken without knowledge of future requests. Further, the network in PRT is directed. The complexity of the routing problems together with the fact that routing algorithms for PRT essentially have to run in real-time often leads to the choice of a fast sequential scheme. The simplicity of such schemes stems from the property that a chosen route is never changed later. This is as well the main drawback of it, potentially leading to large detours. It is natural to ask how much one could gain by using a more adaptive routing strategy. This question is one of the core motivations of this second part. We first suggest a variation to the routing model used in the first part which is suitable for PRT. We show that the routing problem remains hard in the directed setting. Further, we introduce a capacity notion for PRT networks and derive a bound for it. Computational results show that the capacity bound is close to the achievable throughput. It therefore is a useful quantity for estimating network capacity in PRT system design. We then introduce a new adaptive routing algorithm that repeatedly uses solutions to an LP as a guide to route vehicles. New requests are integrated into the LP as soon as they appear and the routing is reoptimized over all vehicles concurrently. We provide computational results that give evidence of the potential gains of an adaptive routing strategy. For this we compare the presented adaptive strategy to sequential routing and to a simple distributed routing strategy in a number of scenarios. Diese Dissertationsarbeit untersucht das konfliktfreie Befördern von Fahrzeugen durch Schienennetzwerke - eine Herausforderung, wie sie oft in verschiedensten Anwendungen in den Transport- und Logistikbranchen vorkommt. Der bekannteste Ansatz für die konfliktfreie Fahrplanung ist ein sequentieller, in dem eine Anfrage nach der anderen mit einer möglichst kurzen Reisezeit eingeplant wird, ohne mit den früheren Anfragen in Konflikt zu geraten. Solche Ansätze haben oft keine Qualitätsgarantien für den resultierenden Fahrplan, und es besteht ein Bedarf für ein besseres theoretisches Verständnis. Das Problem der konfliktfreien Fahrzeugbeförderung ist auch von Interesse durch die enge Verwandtschaft mit dem besser bekannten und untersuchten Problem der Datenbeförderung durch Kommunikationskanäle. Im ersten Teil der Dissertation präsentieren wir neue theoretische Resultate für den Fall von ungerichteten (in beiden Richtungen befahrbaren) Schienennetzwerken. Wir betrachten ein natürliches Modell für die konfliktfreie Beförderung eines Sets von k Fahrzeugen. Zuvor war kein effizienter Algorithmus mit einer sublinearen (in k) Approximationsgarantie für allgemeine Netzwerktopologien bekannt. Wir zeigen, dass es NP-schwer ist, eine optimale Lösung zu finden, sogar wenn das Netzwerk nur aus einem Pfad besteht. Wir präsentieren einen Algorithmus für Baum-Netzwerke, der auf dem sequentiellen Ansatz aufbaut und zu einem Fahrplan führt, der alle Fahrzeuge in Zeit O(OPT) + k ans Ziel befördert. Indem wir dieses Resultat mit Methoden aus dem Bereich der Datenbeförderung kombinieren, erhalten wir den ersten effizienten Algorithmus mit sublinearer Approximationsgarantie von O(√k). Zusätzlich präsentieren wir einen randomisierten Algorithmus der zu Lösungen der Länge O(polylog(k)) • OPT + k führt. Der Ansatz generiert Baumgraphen, die in eine komprimierte Version des Netzwerks eingebettet werden, womit eine Approximationsgarantie erreicht werden kann die unabhängig von der Graphgrösse ist. Der zweite Teil der Dissertation handelt von der Beförderungen von Fahrzeugen in Personal Rapid Transit (PRT). PRT ist ein öffentliches Verkehrsmittel in welchem Passagiere auf Verlangen durch kleine automatisierte Fahrzeuge befördert werden. Zentrale Steuerung der Fahrzeuge führt zu interessanten Möglichkeiten für die optimierte Nutzung der Schienenressourcen. Die Fahrplanerstellung für PRT ist ein Online-Problem in dem die Transportaufträge über die Zeit eintreffen. Entscheidungen müssen ebenfalls über die Zeit getroffen werden, ohne Kenntnis der zukünftigen Aufträge. Ein weiterer Unterschied zum ersten Teil der Dissertation ist, dass die Schienen in PRT nur in eine Richtung befahren werden. Die Komplexität des PRT Beförderungs- Problems und die Anforderung, dass die Fahrpläne in Echtzeit berechnet werden müssen, führt oft zur Wahl von schnellen sequentiellen Algorithmen. Die Einfachheit dieser Ansätze ist bedingt durch die Eigenschaft, dass ein geplanter Fahrplan nicht mehr geändert wird sobald er einmal berechnet wurde. Diese Eigenschaft ist gleichzeitig der grösste Nachteil eines solchen Ansatzes, da sie zu grossen Umwegen oder Verzögerungen führen kann. Eine natürliche Frage ist, wie viel man gewinnen kann wenn man adaptive Strategien verwendet. Diese Frage steht im Zentrum dieses zweiten Dissertationsteils. Zuerst stellen wir eine auf PRT zugeschnittene Variation des mathematischen Modells aus dem ersten Dissertationsteils vor. Wir zeigen, dass das Beförderungs-Problem auch in dieser Variante NP-schwer bleibt. Weiter führen wir einen Kapazitätsbegriff für PRT Netzwerke ein und beweisen eine obere Schranke für diese. Mit Hilfe von Simulationen können wir zeigen, dass die Kapazitätsschranke nicht weit vom erreichbaren Netzwerk-Durchsatz entfernt ist. Sie kann deshalb eine nützliche Grösse zur Abschätzung der Netzwerkkapazität in der Designphase von neuen PRT Systemen sein. Dann präsentieren wir einen neuen adaptiven Algorithmus, der den Fahrplan auf der Grundlage von LP Lösungen erstellt. Neue Aufträge werden gleich beim Eintreffen in das LP integriert und der Fahrplan wird neu berechnet, für alle Fahrzeuge gleichzeitig. Wir zeigen mit Hilfe von Simulationsresultaten das Potential solch adaptiver Strategien. Wir vergleichen den neuen adaptiven Ansatz mit dem sequentiellen Ansatz und mit einem einfachen dezentralisierten Algorithmus in einer Anzahl von Szenarien.

Author: Jee Eun Kang
Publisher:
ISBN: 9781303328107
Category :
Languages : en
Pages : 241

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Book Description
This dissertation focuses on the integration of the Household Activity Pattern Problem (HAPP) with various locational decisions considering both supply and demand sides. We present several methods to merge these two distinct areas--transportation infrastructure and travel demand procedures--into an integrated framework that has been previously exogenously linked by feedback or equilibrium processes. From the demand side, travel demand for non-primary activities is derived from the destination choices that a traveler makes that minimizes travel disutility within the context of considerations of daily scheduling and routing. From the supply side, the network decisions are determined as an integral function of travel demand rather than a given fixed OD matrix. First, the Location Selection Problem for the Household Activity Pattern Problem (LSP-HAPP) is developed. LSP-HAPP extends the HAPP by adding the capability to make destination choices simultaneously with other travel decisions of household activity allocation, activity sequence, and departure time. Instead of giving a set of pre-fixed activity locations to visit, LSP-HAPP chooses the location for certain activity types given a set of candidate locations. A dynamic programming algorithm is adopted and further developed for LSP-HAPP in order to deal with the choices among a sizable number of candidate locations within the HAPP modeling structure. Potential applications of synthetic pattern generation based on LSP-HAPP formulation are also presented. Second, the Location - Household Activity Pattern Problem (Location-HAPP), a facility location problem with full-day scheduling and routing considerations is developed. This is in the category of Location-Routing Problems (LRPs), where the decisions of facility location models are influenced by possible vehicle routings. Location-HAPP takes the set covering model as a location strategy, and HAPP as the scheduling and routing tool. The proposed formulation isolates each vehicle's routing problem from those of other vehicles and from the master set covering problem. A modified column generation that uses a search method to find a column with a negative reduced price is proposed. Third, the Network Design Problem is integrated with the Household Activity Pattern Problem (NDP-HAPP) as a bilevel optimization problem. The bilevel structure includes an upper level network design while the lower level includes a set of disaggregate household itinerary optimization problems, posed as HAPP or LSP-HAPP. The output of upper level NDP (level-of-service of the transportation network) becomes input data for the lower level HAPP that generates travel demand which becomes the input for the NDP. This is advantageous over the conventional NDP that outputs the best set of links to invest in, given an assumed OD matrix. Because the proposed NDP-HAPP can output the same best set of links, a new OD matrix and a detailed temporal distribution of activity participation and travel are created. A decomposed heuristic solution algorithm that represents each decision makers' rationale shows optimality gaps of as much as 5% compared to exact solutions when tested with small examples. Utilizing the aforementioned models, two transportation sustainability studies are then conducted for the adoption of Alternative Fuel Vehicles (AFVs). The challenges in adopting AFVs are directly related to the transportation infrastructure problems since the initial AFV refueling locations will need to provide comparable convenient travel experience for the early adopters when compared to the already matured gasoline fuel based transportation infrastructure. This work demonstrates the significance of the integration between travel demand model and infrastructure problems, but also draws insightful policy measurements regarding AFV adoption. The first application study attempts to measure the household inconvenience level of operating AFVs. Two different scenarios are examined from two behavioral assumptions - keeping currently reported pattern and minimizing the inconvenience cost through HAPPR or HAPPC. From these patterns, the personal or household inconvenience level is derived as compared to the original pattern, providing quantified data on how the public sector would compensate for the increases in travel disutility to ultimately encourage the attractiveness of AFVs. From the supply side of the AFV infrastructure, Location-HAPP is applied to the incubation of the minimum refueling infrastructure required to support early adoption of Hydrogen Fuel Cell Vehicles (HFCVs). One of the early adoption communities targeted by auto manufacturers is chosen as the study area, and then three different values of accessibility are tested and measured in terms of tolerances to added travel time. Under optimal conditions, refueling trips are found to be toured with other activities. More importantly, there is evidence that excluding such vehicle-infrastructure interactions as well as routing and scheduling interactions can result in over-estimation of minimum facility requirement.

Author: Bruce L. Golden
Publisher: Springer Science & Business Media
ISBN: 0387777784
Category : Business & Economics
Languages : en
Pages : 584

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In a unified and carefully developed presentation, this book systematically examines recent developments in VRP. The book focuses on a portfolio of significant technical advances that have evolved over the past few years for modeling and solving vehicle routing problems and VRP variations. Reflecting the most recent scholarship, this book is written by one of the top research scholars in Vehicle Routing and is one of the most important books in VRP to be published in recent times.

Author: Jan Ehmke
Publisher: Springer Science & Business Media
ISBN: 1461436281
Category : Business & Economics
Languages : en
Pages : 201

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Book Description
​As urban congestion continues to be an ever increasing problem, routing in these settings has become an important area of operations research. This monograph provides cutting-edge research, utilizing the recent advances in technology, to quantify the value of dynamic, time-dependent information for advanced vehicle routing in city logistics. The methodology of traffic data collection is enhanced by GPS based data collection, resulting in a comprehensive number of travel time records. Data Mining is also applied to derive dynamic information models as required by time-dependent optimization. Finally, well-known approaches of vehicle routing are adapted in order to handle dynamic information models. This book interweaves the usually distinct areas of traffic data collection, information retrieval and time-dependent optimization by an integrated methodological approach, which refers to synergies of Data Mining and Operations Research techniques by example of city logistics applications. These procedures will help improve the reliability of logistics services in congested urban areas.​

Author: Kim Guldstrand Larsen
Publisher: MDPI
ISBN: 3039280465
Category : Technology & Engineering
Languages : en
Pages : 286

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Book Description
Energy systems worldwide are undergoing major transformation as a consequence of the transition towards the widespread use of clean and sustainable energy sources. Basically, this involves massive changes in technical and organizational levels together with tremendous technological upgrades in different sectors ranging from energy generation and transmission systems down to distribution systems. These actions generate huge science and engineering challenges and demands for expert knowledge in the field to create solutions for a sustainable energy system that is economically, environmentally, and socially viable while meeting high security requirements. This book covers these promising and dynamic areas of research and development, and presents contributions in sustainable energy systems planning, integration, and management. Moreover, the book elaborates on a variety of topics, ranging from design and planning of small- to large-scale energy systems to the operation and control of energy networks in different sectors, namely electricity, heat, ‎and transport.

Author: United States. Civil Aeronautics Board
Publisher:
ISBN:
Category : Aeronautics, Commercial
Languages : en
Pages : 1292

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