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  • 1.
    Andersson, Tobias
    et al.
    Linköping University, The Institute of Technology. Linköping University, Department of Science and Technology.
    Häll, Carl Henrik
    Linköping University, The Institute of Technology. Linköping University, Department of Science and Technology.
    Användning av GIS i kombination med operationsanalys för effektivare transporter2006In: GeoInfo 2006,2006, 2006Conference paper (Other academic)
  • 2.
    Fowler, Scott
    et al.
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Häll, Carl Henrik
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Yuan, Di
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Baravdish, George
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Mellouk, Abdelhamid
    University of Paris-Est Creteil VdM (UPEC), France.
    Analysis of vehicular wireless channel communication via queueing theory model2014In: Communications (ICC) 2014 IEEE International Conference on Communications, IEEE , 2014, p. 1736-1741Conference paper (Refereed)
    Abstract [en]

    The 4G standard Long Term Evolution (LTE) has been developed for high-bandwidth mobile access for today's data-heavy applications, consequently, a better experience for the end user. Since cellular communication is ready available, LTE communication has been designed to work at high speeds for vehicular communication. The challenge is that the protocols in LTE/LTE-Advanced should not only provide good packet delivery but also adapt to changes in the network topology due to vehicle volume and vehicular mobility. It is a critical requirement to ensure a seamless quality of experience ranging from safety to relieving congestion as deployment of LTE/LTE-Advanced become common. This requires learning how to improve the LTE/LTE-Advanced model to better appeal to a wider base and move toward additional solutions. In this paper we present a feasibility analysis for performing vehicular communication via a queueing theory approach based on a multi-server queue using real LTE traffic. A M/M/m model is employed to evaluate the probability that a vehicle finds all channels busy, as well as to derive the expected waiting times and the expected number of channel switches. Also, when a base station (eNB) becomes overloaded with a single-hop, a multi-hop rerouting optimization approach is presented.

  • 3. Order onlineBuy this publication >>
    Häll, Carl Henrik
    Linköping University, Department of Science and Technology. Linköping University, The Institute of Technology.
    A Framework for Evaluation and Design of an Integrated Public Transport System2006Licentiate thesis, monograph (Other academic)
    Abstract [en]

    Operators of public transport always try to make their service as attractive as possible, to as many persons as possible and in a so cost effective way as possible. One way to make the service more attractive, especially to elderly and disabled, is to offer door-to-door transportation. The cost for the local authorities to provide this service is very high and increases every year.

    To better serve the needs of the population and to reduce the cost for transportation of elderly and disabled, public transportation systems are evolving towards more flexible solutions. One such flexible solution is a demand responsive service integrated with a fixed route service, together giving a form of flexible public transport system. The demand responsive service can in such a system be used to carry passengers from their origin to a transfer location to the fixed route network, and/or from the fixed route network to their destination.

    This thesis concerns the development of a framework for evaluation and design of such an integrated public transport service. The framework includes a geographic information system, optimization tools and simulation tools. This framework describes how these tools can be used in combination to aid the operators in the planning process of an integrated service. The thesis also presents simulations made in order to find guidelines of how an integrated service should be designed. The guidelines are intended to help operators of public transport to implement integrated services and are found by evaluating the effects on availability, travel time, cost and other service indicators for variations in the design and structure of the service.

    In a planning system for an integrated public transport service, individual journeys must in some way be scheduled. For this reason the thesis also presents an exact optimization model of how journeys should be scheduled in this kind of service.

  • 4. Order onlineBuy this publication >>
    Häll, Carl Henrik
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Modeling and Simulation of Dial-a-Ride and Integrated Public Transport Services2011Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Traditional public transport systems are most often insufficient to provide a good transport service to everyone. Especially, it is not always possible for elderly and disabled persons to use the regular system consisting of timetabled services operating along fixed routes. Normally there is some specific service, often called paratransit, offered to these groups of customers. Such transport services provide better service to these customers, but to a higher cost. This thesis considers planning and evaluation of public transport services that are based on the concept of a dial-a-ride service. This kind of service is suitable for elderly and disabled and often operated as a door-to-door service, where customers are served on demand and rides are coordinated via a call-center. The thesis is divided into two parts. In the first part, a modeling system for simulation of dial-a-ride services is presented. It can be used as a tool to study how different ways of operating a dial-a-ride service, affect the performance and efficiency of the service. This system is used to evaluate how algorithmic changes, based on ruin-and-recreate methods, can improve the replanning of already inserted requests, and thereby improve the scheduling. The modeling system is also used to examine the effects of using zone-based distance estimates instead of true, address-based, distances when computing the schedules. The results show that only small differences are found.The second part of the thesis concerns an extension to dial-a-ride services. By combining a dial-a-ride service with a fixed route service, an integrated dial-a-ride service is created, where some part of each journey may be carried out by the fixed route service. An exact mathematical formulation of this problem is presented and it is shown that the formulation is strengthened by valid inequalities, variable substitution and subtour elimination constraints. Simulations of an integrated service are also performed to analyze and evaluate how the attractiveness and operating costs of the service depend on how the demand responsive service is operated.

    List of papers
    1. A modeling system for simulation of dial-a-ride services
    Open this publication in new window or tab >>A modeling system for simulation of dial-a-ride services
    2012 (English)In: Public Transport, ISSN 1866-749X, E-ISSN 1613-7159, Vol. 4, no 1, p. 17-37Article in journal (Refereed) Published
    Abstract [en]

    We present a modeling system for simulation of dial-a-ride services. It can be used as a tool for understanding and study how different designs, and different ways to operate a dial-a-ride service, affect the performance and efficiency of the service. The system simulates the operation of a dynamic dial-a-ride service that operates with multiple fleets of vehicles with different capacities, schedules and depots. It can be used to investigate how the setting of service and cost parameters and the design of the service affect the total cost for the operator and level of service for the customer. We describe the different modules in the system and the possible uses of the system. A short simulation study is performed to exemplify how it can be used. In this study the effects of including costs for customer discomfort are evaluated.

    Place, publisher, year, edition, pages
    Berlin / Heidelberg: Springer, 2012
    Keywords
    dial-a-ride, optimization, public transport, simulation
    National Category
    Other Engineering and Technologies not elsewhere specified
    Identifiers
    urn:nbn:se:liu:diva-68057 (URN)10.1007/s12469-012-0052-6 (DOI)
    Available from: 2011-05-09 Created: 2011-05-09 Last updated: 2017-12-11Bibliographically approved
    2. Improving paratransit scheduling using ruin and recreate methods
    Open this publication in new window or tab >>Improving paratransit scheduling using ruin and recreate methods
    2013 (English)In: Transportation planning and technology (Print), ISSN 0308-1060, E-ISSN 1029-0354, Vol. 36, no 4, p. 377-393Article in journal (Refereed) Published
    Abstract [en]

    In this paper we study the effects of using ruin and recreate methods in a replanning phase of a dynamic dial-a-ride problem. Several such methods are proposed, and a modeling system is used to evaluate how they improve the quality of the solutions. We show that simple changes to existing planning methods can increase the efficiency of the service. Two cases, with different forms of costs inflicted on the vehicles, are evaluated and significant improvements are found in both cases. The best results of our study are found with ruin methods based on removal of sequences of requests.

    Place, publisher, year, edition, pages
    Taylor & Francis, 2013
    Keywords
    dial-a-ride, public transport, optimization
    National Category
    Other Engineering and Technologies not elsewhere specified
    Identifiers
    urn:nbn:se:liu:diva-68059 (URN)10.1080/03081060.2013.798488 (DOI)000320098900005 ()
    Available from: 2011-05-09 Created: 2011-05-09 Last updated: 2018-08-23Bibliographically approved
    3. Effects of distance estimation methods in dial-a-ride planning
    Open this publication in new window or tab >>Effects of distance estimation methods in dial-a-ride planning
    2008 (English)In: Proceedings of the 13thInternational Conference of Hong Kong Society for Transportation Studies,Transportation and Management Science / [ed] Lo, H.P., C.H. Leung and S.M.L Tam, Hong Kong, China: Hong Kong Society of Transportation Studies Ltd. , 2008, p. 751-759Conference paper, Published paper (Refereed)
    Abstract [en]

    Paratransit in form of dial-a-ride service is widely used in Sweden. A main planning system in Sweden uses pre-calculated distance matrices, based on aggregated geographical zones. A trip between two zones is thereby assumed to take a certain time independent of where in the zones the actual pick-up and drop-off points are located. The aim of this paper is to examine the effects of using address-based shortest path calculations instead of zone-based distance estimates. A simulation environment is implemented in C#.Net, based on a standard formulation of the dynamic dial-a-ride problem, and simulations have been performed on historical data from the city of Göteborg. To evaluate the solutions, it is not adequate to evaluate only the objective function value, since a lower estimation of the distances will likely give a lower objective function value. Therefore we also discuss how to evaluate different solutions in other terms than objective function values.

    Place, publisher, year, edition, pages
    Hong Kong, China: Hong Kong Society of Transportation Studies Ltd., 2008
    Keywords
    transportation, planning, dial-a-ride
    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:liu:diva-43892 (URN)75043 (Local ID)978-988-98847-3-4 (ISBN)75043 (Archive number)75043 (OAI)
    Conference
    The 13th International Conference of Hong Kong Society for Transportation Studies, 13-15 December, Hong Kong, China
    Available from: 2009-10-10 Created: 2009-10-10 Last updated: 2011-05-11Bibliographically approved
    4. The Integrated Dial-a-Ride Problem
    Open this publication in new window or tab >>The Integrated Dial-a-Ride Problem
    2009 (English)In: Public Transport, ISSN 1866-749X, E-ISSN 1613-7159, Vol. 1, no 1, p. 39-54Article in journal (Refereed) Published
    Abstract [en]

    In this paper we present a formulation of the Integrated Dial-a-Ride (IDARP). This problem is to schedule dial-a-ride requests, where some part of each journey may be carried out by a fixed route service. The IDARP is a generalization of the Dial-a-Ride Problem. An arc-based formulation is proposed, and it is shown how the model can be made easier to solve by arc elimination, variable substitution and the introduction of subtour elimination constraints. Small instances of the IDARP can be solved using an exact solution method, and one such instance is studied. We also describe how input and output data can be created and visualized in a geographic information system.

    Place, publisher, year, edition, pages
    Berlin / Heidelberg: Springer, 2009
    Keywords
    public transport, dial-a-ride, optimization, IDARP
    National Category
    Other Engineering and Technologies not elsewhere specified
    Identifiers
    urn:nbn:se:liu:diva-51818 (URN)10.1007/s12469-008-0006-1 (DOI)
    Available from: 2009-11-19 Created: 2009-11-19 Last updated: 2017-12-12Bibliographically approved
    5. Evaluation of an integrated public transport system: a simulation approach
    Open this publication in new window or tab >>Evaluation of an integrated public transport system: a simulation approach
    2008 (English)In: Archives of Transport, ISSN 0866-9546, Vol. 20, no 1-2, p. 29-46Article in journal (Refereed) Published
    Abstract [en]

    Integrated public transportation service is a new interesting form of service combining a fixed route service with a demand responsive service. When designing such a service, it is important to analyse and evaluate how the attractiveness and operating costs for the service depend on the type of demand responsive service used, the design parameters related to the fleet of vehicles, the structure of the transportation network and on the personal service commitments made to the passengers. In this paper, we show how simulation can be used to perform these analyses. The performed simulations also give guidelines to help operators of public transport to design the service. The evaluation is made using the LlTRES-2 public transport modelling system. The results show the importance of the design of the demand responsive part of the integrated service.

    Place, publisher, year, edition, pages
    Warsaw: Univ. of Technology, Institute of Transport, 2008
    Keywords
    public transport, simulation
    National Category
    Other Engineering and Technologies not elsewhere specified
    Identifiers
    urn:nbn:se:liu:diva-51813 (URN)
    Available from: 2009-11-18 Created: 2009-11-18 Last updated: 2013-12-19Bibliographically approved
  • 5.
    Häll, Carl Henrik
    et al.
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Andersson, Henrik
    Department of Industrial Economics and Technology Management, Norwegian University of Science and Technology.
    Lundgren, Jan T.
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Värbrand, Peter
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    The Integrated Dial-a-Ride Problem2009In: Public Transport, ISSN 1866-749X, E-ISSN 1613-7159, Vol. 1, no 1, p. 39-54Article in journal (Refereed)
    Abstract [en]

    In this paper we present a formulation of the Integrated Dial-a-Ride (IDARP). This problem is to schedule dial-a-ride requests, where some part of each journey may be carried out by a fixed route service. The IDARP is a generalization of the Dial-a-Ride Problem. An arc-based formulation is proposed, and it is shown how the model can be made easier to solve by arc elimination, variable substitution and the introduction of subtour elimination constraints. Small instances of the IDARP can be solved using an exact solution method, and one such instance is studied. We also describe how input and output data can be created and visualized in a geographic information system.

  • 6.
    Häll, Carl Henrik
    et al.
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, Faculty of Science & Engineering.
    Ceder, Avishai (Avi)
    Department of Civil and Environmental Engineering, University of Auckland, New Zealand, and International Development and Cooperation (IDEC), Hiroshima University, Hiroshima, Japan.
    Ekström, Joakim
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, Faculty of Science & Engineering.
    Quttineh, Nils-Hassan
    Linköping University, Department of Mathematics, Optimization . Linköping University, Faculty of Science & Engineering.
    Adjustments of public transit operations planning process for the use of electric buses2019In: Journal of Intelligent Transportation Systems / Taylor & Francis, ISSN 1547-2450, E-ISSN 1547-2442, Vol. 23, no 3, p. 216-230Article in journal (Refereed)
    Abstract [en]

    This work investigates and discusses how the introduction of electric buses (EB), both battery and plug-in hybrid EB, will and should change the operations planning of a public transit system. It is shown that some changes are required in the design of a transit route network, and in the timetabling and vehicle scheduling processes. Other changes are not required, but are advisable, using this opportunity upon the introduction of EB. The work covers the main characteristics of different types of EB with a short description, including the most popular charging technologies, and it presents the generally accepted transit operations planning process. Likewise, it describes and analytically formulates new challenges that arise when introducing EB. The outcome of the analyses shows that multiple new considerations must take place. It is also shown that the different charging techniques will influence the operations planning process in different ways and to a varying extent. With overnight, quick and continuous charging, the main challenges are in the network route design step, given the possibility of altering the existing network of routes, with efficient and optimal changes of the timetabling and vehicle scheduling components. An illustrative example, based on four bus lines in Norrköping, Sweden, is formulized and introduced using three problem instances of 48, 82, and 116 bus trips. The main results exhibit the minimum number of vehicles required using different scenarios of charging stations.

  • 7.
    Häll, Carl Henrik
    et al.
    Linköping University, Department of Science and Technology. Linköping University, The Institute of Technology.
    Högberg, Magdalena
    Astando AB, 11221 Stockholm, Sweden.
    Effects of distance estimation methods in dial-a-ride planning2008In: Proceedings of the 13thInternational Conference of Hong Kong Society for Transportation Studies,Transportation and Management Science / [ed] Lo, H.P., C.H. Leung and S.M.L Tam, Hong Kong, China: Hong Kong Society of Transportation Studies Ltd. , 2008, p. 751-759Conference paper (Refereed)
    Abstract [en]

    Paratransit in form of dial-a-ride service is widely used in Sweden. A main planning system in Sweden uses pre-calculated distance matrices, based on aggregated geographical zones. A trip between two zones is thereby assumed to take a certain time independent of where in the zones the actual pick-up and drop-off points are located. The aim of this paper is to examine the effects of using address-based shortest path calculations instead of zone-based distance estimates. A simulation environment is implemented in C#.Net, based on a standard formulation of the dynamic dial-a-ride problem, and simulations have been performed on historical data from the city of Göteborg. To evaluate the solutions, it is not adequate to evaluate only the objective function value, since a lower estimation of the distances will likely give a lower objective function value. Therefore we also discuss how to evaluate different solutions in other terms than objective function values.

  • 8.
    Häll, Carl Henrik
    et al.
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Högberg, Magdalena
    Astando AB, Stockholm, Sweden.
    Lundgren, Jan T.
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    A modeling system for simulation of dial-a-ride services2012In: Public Transport, ISSN 1866-749X, E-ISSN 1613-7159, Vol. 4, no 1, p. 17-37Article in journal (Refereed)
    Abstract [en]

    We present a modeling system for simulation of dial-a-ride services. It can be used as a tool for understanding and study how different designs, and different ways to operate a dial-a-ride service, affect the performance and efficiency of the service. The system simulates the operation of a dynamic dial-a-ride service that operates with multiple fleets of vehicles with different capacities, schedules and depots. It can be used to investigate how the setting of service and cost parameters and the design of the service affect the total cost for the operator and level of service for the customer. We describe the different modules in the system and the possible uses of the system. A short simulation study is performed to exemplify how it can be used. In this study the effects of including costs for customer discomfort are evaluated.

  • 9.
    Häll, Carl Henrik
    et al.
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Lundgren, Jan T.
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Peterson, Anders
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Improving the efficiency of swedish paratransit: an application of the dial-a-ride problem2009Conference paper (Other academic)
  • 10.
    Häll, Carl Henrik
    et al.
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Lundgren, Jan T.
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Voss, Stefan
    University of Hamburg, Institute of Information Systems, Germany.
    Evaluating the performance of a dial-a-ride service using simulation2012Conference paper (Other academic)
    Abstract [en]

    In this paper we study the effects of changes to a paratransit system operated as a dynamic dial-a-ride service. The scheduling of requests is limited by time window constraints and maximum ride time constraints, and costs for customer discomfort in form of waiting time and excess ride time, are considered in the planning of the service. The parameters defining these constraints and costs are evaluated based on simulations of a real-world scenario.

    Several different criteria, both regarding customer level of service and operational costs, are used to evaluate the simulation results. By showing what parameters that have a large impact on the different evaluation criteria, we can give guidelines to operators of public transport of how to design their dial-a-ride services. Numerical results are presented and from these results conclusions are drawn regarding what parameters are most important in dynamic dial-a-ride services.

  • 11.
    Häll, Carl Henrik
    et al.
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Lundgren, Jan T.
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Voß, Stefan
    Institute of Information Systems, University of Hamburg, Hamburg, Germany.
    Evaluating the performance of a dial-a-ride service using simulation2015In: Public Transport, ISSN 1866-749X, E-ISSN 1613-7159, Vol. 7, no 2, p. 139-157Article in journal (Refereed)
    Abstract [en]

    In this paper we study the effects of changes to a paratransit system operated as a dynamic dial-a-ride service. The scheduling of requests is limited by time window constraints and maximum ride time constraints; costs for customer discomfort in form of waiting time and excess ride time are considered in the planning of the service. The parameters defining these constraints and costs are evaluated based on simulations of a real-world scenario. Several different criteria, both regarding customer level of service and operational costs, are used to evaluate the simulation results. By showing which parameters have a large impact on the different evaluation criteria, we can give guidelines to operators of public transport of how to design their dial-a-ride services. Numerical results are presented and from these results conclusions are drawn regarding which parameters are most important in dynamic dial-a-ride services.

  • 12.
    Häll, Carl Henrik
    et al.
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Lundgren, Jan T.
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Värbrand, Peter
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Evaluation of an integrated public transport system: a simulation approach2008In: Archives of Transport, ISSN 0866-9546, Vol. 20, no 1-2, p. 29-46Article in journal (Refereed)
    Abstract [en]

    Integrated public transportation service is a new interesting form of service combining a fixed route service with a demand responsive service. When designing such a service, it is important to analyse and evaluate how the attractiveness and operating costs for the service depend on the type of demand responsive service used, the design parameters related to the fleet of vehicles, the structure of the transportation network and on the personal service commitments made to the passengers. In this paper, we show how simulation can be used to perform these analyses. The performed simulations also give guidelines to help operators of public transport to design the service. The evaluation is made using the LlTRES-2 public transport modelling system. The results show the importance of the design of the demand responsive part of the integrated service.

  • 13.
    Häll, Carl Henrik
    et al.
    Linköping University, The Institute of Technology. Linköping University, Department of Science and Technology.
    Lundgren, Jan
    Linköping University, The Institute of Technology. Linköping University, Department of Science and Technology.
    Värbrand, Peter
    Linköping University, The Institute of Technology. Linköping University, Department of Science and Technology.
    Simulation and evaluation of integrated public transport2005In: Advanced OR and AI Methods in Transportation, Proceedings of the 10th Jubilee Meeting of the EURO Working Group on Transportation,2005, Poznan, Poland: Publishing House of the Poznan University of Technology , 2005, p. 271-Conference paper (Refereed)
  • 14.
    Häll, Carl Henrik
    et al.
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Peterson, Anders
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Improving paratransit scheduling using ruin and recreate methods2013In: Transportation planning and technology (Print), ISSN 0308-1060, E-ISSN 1029-0354, Vol. 36, no 4, p. 377-393Article in journal (Refereed)
    Abstract [en]

    In this paper we study the effects of using ruin and recreate methods in a replanning phase of a dynamic dial-a-ride problem. Several such methods are proposed, and a modeling system is used to evaluate how they improve the quality of the solutions. We show that simple changes to existing planning methods can increase the efficiency of the service. Two cases, with different forms of costs inflicted on the vehicles, are evaluated and significant improvements are found in both cases. The best results of our study are found with ruin methods based on removal of sequences of requests.

  • 15.
    Olstam, Johan
    et al.
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, Faculty of Science & Engineering.
    Häll, Carl-Henrik
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, Faculty of Science & Engineering.
    Smith, Göran
    Viktoria Swedish ICT, Gothenburg, Sweden.
    Habibovic, Azra
    Viktoria Swedish ICT, Gothenburg, Sweden.
    Anund, Anna
    Swedish National Road and Transport Research Institute, VTI.
    Dynamic bus lanes in Sweden – a pre-study: PROVDYK – Final report2015Report (Other academic)
    Abstract [en]

    Dedicated bus lanes and bus streets have, in recent years, become common measures for prioritisation of public transport. By ensuring free path along routes, they increase average speed and travel time reliability of buses. However, a major drawback is that the total traffic capacities of the roads decrease. Hence, these measures are only suitable when the total traffic flow is low enough to allow for a reduction of lanes; if it is possible to reroute adjacent traffic; or if it is possible to extend the road with additional lanes. A supplementary priority measure could be to utilize dynamic bus lanes (also called intermittent bus lanes and bus lanes with intermittent priority). Dynamic bus lanes are only dedicated for buses when and where the buses need them, and otherwise open for all vehicles to use. At any given point, adjacent traffic is only permitted from using the dynamic bus lanes at the stretches where buses are in the vicinity. This report presents the results from a pre-study, investigating the potential that dynamic bus lanes could have as a priority measure for public transport in a Swedish context.

    Knowledge of situations in which dynamic bus lanes have the highest potential, and their implementation requirements is scarce. It is moreover uncertain how they would affect traffic safety, level of service and user experience. Two real world field tests have been conducted; one in Lisbon and one in Melbourne. The installation in Melbourne is now permanently applied for trams on one street. The field test in Lisbon was on the contrary not made permanent, although the results showed large benefits for buses and limited adverse effects on other vehicles. Dynamic bus lanes have also been investigated by means of traffic analysis and traffic simulation experiments. In general, these studies show that the effects on travel time for buses are in general positive and delays for other vehicles are limited. Results from example calculations in this pre-study show that this also could be true for a Swedish context. It has also been identified that the effects on travel times are highly dependent on factors such as: the total traffic flow; the bus flow, the capacity of roads and junctions; the distance between junctions and bus stops; the type of bus stops and the yielding rules at bus stops. The effects on travel time variations are unclear and need to be further investigated.

    Few rigorous research studies have in general been undertaken to measure the user experiences or road safety implications of bus priority schemes, and evidence from those that do exist are mixed. Anyhow, the experiences from Lisbon and Melbourne suggest that drivers in adjacent lanes in general understand and accept that they are deprived of the right to use the lane when the buses need it, and that they will behave appropriately. Neither of the field tests has observed any negative impact on road safety. A workshop was conducted within this pre-study in order to further investigate plausible user experiences. The results indicate that bus drivers’ stress levels could be reduced; the relative attractiveness of travelling by bus might rise; and that motorists probably would experience the introduction of dynamic bus lanes as neither good nor bad, as long as the system is fairly intuitive.

    Technical solutions for implementing dynamic bus lanes exist. A dynamic bus lane system would require development of a system control unit and integration with bus sensors, sensors for traffic flow measurement, variable message signs (to inform road users of the current status of the dynamic bus lane) and traffic signals. It is moreover, in Sweden, possible to develop a local traffic rule that regulates dynamic bus lanes. However, the rule needs to be properly specified, designed, communicated, signed and marked on the road.

    The overall conclusion form the pre-study is that dynamic bus lanes could be a useful complementary priority measure for public transport vehicles in Sweden, especially when dedicated bus lanes are not feasible or desirable. However, a real world installation in Sweden, including pre implementation traffic analysis, is needed, in order to further investigate the potential and consequences. Thus, the next step is to plan for an implementation on a specific road stretch. That would include both estimation of costs, and generate input to further studies of effect on level of service and user experience. Driving simulators and traffic simulation experiments are applicable methods for investigating these issues.

  • 16.
    Peterson, Anders
    et al.
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, Faculty of Science & Engineering.
    Wahlborg, Magnus
    Railway Traffic and sale, Trafikverket, Borlänge.
    Häll, Carl Henrik
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, Faculty of Science & Engineering.
    Schmidt, Christiane
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, Faculty of Science & Engineering.
    Kordnejad, Behzad
    Transportplanering, Royal Institute of Technology (KTH), Stockholm, Sweden.
    Warg, Jennifer
    Transportplanering, Royal Institute of Technology (KTH), Stockholm, Sweden.
    Johansson, Ingrid
    Transportplanering, Royal Institute of Technology (KTH), Stockholm, Sweden.
    Joborn, Martin
    Systems Engineering, RISE Research Institutes of Sweden, Göteborg, Sweden.
    Gestrelius, Sara
    Systems Engineering, RISE Research Institutes of Sweden, Göteborg, Sweden.
    Törnquist Krasemann, Johanna
    Department of Computer Science, Blekinge tekniska högskola, Karlskrona, Sweden.
    Josyula, Sai Prashanth
    Department of Computer Science, Blekinge tekniska högskola, Karlskrona, Sweden.
    Palmqvist, Carl-William
    Transport Systems and Logistics, Lund University, Sweden.
    Lidén, Tomas
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, Faculty of Science & Engineering. Swedish National Road and Transport Research Institute (VTI), Linköping, Sweden.
    Deliverable D 3.1: Analysis of the gap between daily timetable and operational traffic2019Report (Other academic)
    Abstract [en]

    Fr8Rail II/Work-Package 3 Real-time network management and improved methods for timetable planning addresses the problem to improve capacity and punctuality in the railway system by developing concepts and methods for tactical planning and operational traffic. In this report the state-of-the-art has been summarised.

    The aim of the project is to:

    • Propose concepts and methods that improve the annual and short-term timetable planning.
    • Demonstrate how the proposed timetable planning concepts improve the prerequisites for real-time network management.
    • Develop methods and tools that can reduce inefficiencies in real time network management.

    An important aspect is to improve the coordination between yards/terminals and the line network, and between Infrastructure Manager, Yard Managers, and freight Rail Undertakings.

    We motivate our research by the current situation in Sweden, which is characterised by low on-time performance for freight trains, dense and heterogenous traffic on the major railway lines, and a rigid annual timetabling process, which is non-suitable for short-term changes. We believe that better tools for network planning and management on tactical and operational level can help to connect planning and operational processes.

    Aiming for improvements of the operational traffic, there is a need for systematic development of methods applied at several planning horizons, based on both simulation and optimization techniques. Close to operation fast methods are needed, for example, based on meta-heuristics.

    The maintenance planning process and improvement potential have been described. This is a new piece of the puzzle and it is important to close the gap between timetable planning and operational traffic. The different planning processes at the Infrastructure Manager, the Rail Undertakings and the Maintenance Contractors should be aligned.

    When developing new approaches for computational decision-support tools for real-time network management, it is important — but very challenging — to evaluate and benchmark with existing software tools. We also observe that the research stream on computational decision-support and algorithm development for railway traffic management has not yet been sufficiently merged with the corresponding research stream focusing on aspects of human computer interaction.

  • 17.
    Quttineh, Nils-Hassan
    et al.
    Linköping University, Department of Mathematics, Optimization . Linköping University, Faculty of Science & Engineering.
    Häll, Carl Henrik
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, Faculty of Science & Engineering.
    Ekström, Joakim
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, Faculty of Science & Engineering.
    Ceder, Avi
    Department of Civil and Environmental Engineering, University of Auckland, New Zealand.
    Combined Timetabling and Vehicle Scheduling for Electric Buses2017In: Proceedings of the 22nd International Conference of Hong Kong Society for Transportation Studies (HKSTS), December 9-11, 2017, Hong Kong, China, Hong Kong: HKSTS , 2017, , p. 8Conference paper (Other academic)
    Abstract [en]

    In this paper we present a novel mathematical model, integrating the timetabling and vehicle schedulingproblems for electric buses. The objective is to minimize the number of buses while satisfying constraintsconcerning routing and charging, including design choices of where to install charging equipment. Weillustrate the different effects of tackling the timetabling and vehicle scheduling of electric buses as separateproblems or as a joint problem, both for fixed and variable headways. To do so, tests are performed with: (i) given timetable, i.e. solving only the vehicle scheduling problem, (ii) fixed headways for each line, (iii) variable headways. For these tests, a small case based on four bidirectional bus lines is used.

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