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  • 1.
    Abenoza, Roberto
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment.
    Cats, Oded
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning. Department of Transport and Planning, Delft University of Technology, P.O. Box 5048, GA Delft, 2600, Netherlands.
    Susilo, Yusak
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment. KTH, School of Industrial Engineering and Management (ITM), Centres, Integrated Transport Research Lab, ITRL.
    Determinants of traveler satisfaction: Evidence for non-linear and asymmetric effects2019In: Transportation Research Part F: Traffic Psychology and Behaviour, ISSN 1369-8478, E-ISSN 1873-5517, Vol. 66, p. 339-356Article in journal (Refereed)
    Abstract [en]

    Classifying public transport service attributes based on their influence on overall traveler satisfaction can assist stakeholders and practitioners in introducing cost-efficient measures. To date most studies employed methods that were based on the assumption that the impact of service attributes on traveler satisfaction is entirely linear and symmetric. This study examines whether service attributes have a non-linear and asymmetric influence on the overall travel experience by employing the Three-factor theory (basic, performance and exciting factors). The analysis is conducted for different traveler segments depending on their level of captivity, travel frequency by public transport and travel mode used, and is based on a relatively large sample size collected for Stockholm County. Moreover, the estimated models control for important socio-demographic and travel characteristics that have been insofar overlooked. Results are presented in the form of a series of multi-level cubes that represent different essentiality of traveler needs which provide a useful methodological framework to further design quality service improvements that can be applied to various geographical contexts. Our findings highlight that a “one size fits all” approach is not adequate for identifying the needs of distinct traveler segments and of travelers using different travel modes. Furthermore, two-thirds of the attributes are consistently classified into the same factor category which entails important policy implications. This research deepens and expands the very limited knowledge of the application of the three-factor theory in the transport field.

  • 2.
    Andersson, Malin
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning.
    Simuleringsbaserad analys av pendelbåtstrafik i Stockholm2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This paper analyzes how an agent-based simulation model of Stockholm can be used for water transitplanning. A new route for commuters by boat was added to the model of Stockholm’s existingtransport system and evaluated. By comparing results from the model and statistic data fromTrafikförvaltningen Region Stockholm during the morning rush-hour, a scale factor was calculated.The scale factor was later used to adjust the number of travelers on the added new water transit routeas the model underestimate the number of persons who use the available public transport by boat. Thelarge size of the calculated factor made the results uncertain when trying to predict any effects the newroute would have, e.g. on congestion in the system. Simulations of the new transit line resulted in amajority of short trips, between stations were the other public transit options took longer routes. Thetransit stops close to the city centre were used the most and most trips were conducted between them.To gain an improved ability to simulate water transit, continued studies of people’s preferencesregarding mode choice appear to be crucial.

  • 3.
    Babicheva, Tatiana
    et al.
    VEDECOM, 77 Rue Chantiers, F-78000 Versailles, France..
    Burghout, Wilco
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning. VEDECOM, 77 Rue Chantiers, F-78000 Versailles, France..
    Andreasson, Ingmar
    LogistikCtr Goteborg AB, Osbergsgatan 4 A, S-42677 Vastra Frolunda, Sweden..
    Faul, Nadege
    VEDECOM, 77 Rue Chantiers, F-78000 Versailles, France..
    Empty vehicle redistribution and fleet size in autonomous taxi systems2019In: IET Intelligent Transport Systems, ISSN 1751-956X, E-ISSN 1751-9578, Vol. 13, no 4, p. 677-682Article in journal (Refereed)
    Abstract [en]

    This study investigates empty vehicle redistribution algorithms for personal rapid transit and autonomous taxi services. The focus is on passenger service and operator cost. A new redistribution algorithm is presented in this study: index-based redistribution (IBR). IBR is a proactive method, meaning it takes into account both current demand and anticipated future demand, in contrast to reactive methods, which act based on current demand only. From information on currently waiting for passengers, predicted near-future demand and projected arrival of vehicles, IBR calculates an index for each vehicle station, and redistribution is done based on this index. Seven different algorithm combinations are evaluated using a test case in Paris Saclay, France (20 stations and 100 vehicles). A combination of simple nearest neighbours and IBR is shown to be promising. Its results outperform the other methods tested in peak and off-peak demand, in terms of average and maximum passenger waiting times as well as station queue length. The effect of vehicle fleet size on generalised cost is analysed. Waiting times, mileage and fleet size are taken into account while assessing this generalised cost.

  • 4.
    BERG WINCENT, BOEL
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning.
    Gångavstånd för resor med elsparkcykel: En studie baserat på elsparkcykelaktören Voi Technology i Stockholm2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Electric scooters, or e-scooters as they also are called, were launched in California in USA as a bike share system, in 2017. A year later, in September 2018, the Swedish company Voi Technology launched the first e-scooters in Stockholm, Sweden. Bike share systems has been around since the 1960s but has grown substantially in the past 15 years. New technical solutions have solved past problems with theft and payment in bike shares. Since e-scooters are new, there is a lack of research and knowledge about practical use. The study aims to examine how long users of e-scooters walk to utilize the service. Travel data from Voi Technology is used to determine walking distance. The distance from the location where the app was opened to the location where the e-scooter trip begun was measured. The result was also compared the walking distance of other bike share systems and travelers of public transportation. The majority of e-scooter users walk less than 100 meters and 38 per cent walk less than 50 meters. The users have the shortest walking distance in the morning and the longest in the afternoon. During the weekend's users walk further than in weekdays. The users who travel longer distances with the e-scooters don’t walk further than other users. About a third of the users walk in the opposite direction of travel, to some extent, to catch an e-scooter. That indicates that the aim of the user in general seems to be to always have the shortest possible walking distance to the e-scooter.

  • 5.
    Cebecauer, Matej
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning.
    Short-Term Traffic Prediction in Large-Scale Urban Networks2019Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    City-wide travel time prediction in real-time is an important enabler for efficient use of the road network. It can be used in traveler information to enable more efficient routing of individual vehicles as well as decision support for traffic management applications such as directed information campaigns or incident management. 3D speed maps have been shown to be a promising methodology for revealing day-to-day regularities of city-level travel times and possibly also for short-term prediction. In this paper, we aim to further evaluate and benchmark the use of 3D speed maps for short-term travel time prediction and to enable scenario-based evaluation of traffic management actions we also evaluate the framework for traffic flow prediction. The 3D speed map methodology is adapted to short-term prediction and benchmarked against historical mean as well as against Probabilistic Principal Component Analysis (PPCA). The benchmarking and analysis are made using one year of travel time and traffic flow data for the city of Stockholm, Sweden. The result of the case study shows very promising results of the 3D speed map methodology for short-term prediction of both travel times and traffic flows. The modified version of the 3D speed map prediction outperforms the historical mean prediction as well as the PPCA method. Further work includes an extended evaluation of the method for different conditions in terms of underlying sensor infrastructure, preprocessing and spatio-temporal aggregation as well as benchmarking against other prediction methods.

  • 6.
    Cebecauer, Matej
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning.
    Gundlegård, David
    Department of Science and Technology,Linköping University.
    Jenelius, Erik
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning.
    Burghout, Wilco
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning.
    3D Speed Maps and Mean Observations Vectors for Short-Term Urban Traffic Prediction2019In: TRB Annual Meeting Online, Washington DC, US, 2019, p. 1-20Conference paper (Refereed)
    Abstract [en]

    City-wide travel time prediction in real-time is an important enabler for efficient use of the road network. It can be used in traveler information to enable more efficient routing of individual vehicles as well as decision support for traffic management applications such as directed information campaigns or incident management. 3D speed maps have been shown to be a promising methodology for revealing day-to-day regularities of city-level travel times and possibly also for short-term prediction. In this paper, we aim to further evaluate and benchmark the use of 3D speed maps for short-term travel time prediction and to enable scenario-based evaluation of traffic management actions we also evaluate the framework for traffic flow prediction. The 3D speed map methodology is adapted to short-term prediction and benchmarked against historical mean as well as against Probabilistic Principal Component Analysis (PPCA). The benchmarking and analysis are made using one year of travel time and traffic flow data for the city of Stockholm, Sweden. The result of the case study shows very promising results of the 3D speed map methodology for short-term prediction of both travel times and traffic flows. The modified version of the 3D speed map prediction outperforms the historical mean prediction as well as the PPCA method. Further work includes an extended evaluation of the method for different conditions in terms of underlying sensor infrastructure, preprocessing and spatio-temporal aggregation as well as benchmarking against other prediction methods.

  • 7.
    Cebecauer, Matej
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning.
    Jenelius, Erik
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning.
    Burghout, Wilco
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning.
    Integrated framework for real-time urban network travel time prediction on sparse probe data2018In: IET Intelligent Transport Systems, ISSN 1751-956X, E-ISSN 1751-9578, Vol. 12, no 1, p. 66-74Article in journal (Refereed)
    Abstract [en]

    The study presents the methodology and system architecture of an integrated urban road network travel time prediction framework based on low-frequency probe vehicle data. Intended applications include real-time network traffic management, vehicle routing and information provision. The framework integrates methods for receiving a stream of probe vehicle data, map matching and path inference, link travel time estimation, calibration of prediction model parameters and network travel time prediction in real time. The system design satisfies three crucial aspects: computational efficiency of prediction, internal consistency between components and robustness against noisy and missing data. Prediction is based on a multivariate hybrid method of probabilistic principal component analysis, which captures global correlation patterns between links and time intervals, and local smoothing, which considers local correlations among neighbouring links. Computational experiments for the road network of Stockholm, Sweden and probe data from taxis show that the system provides high accuracy for both peak and off-peak traffic conditions. The computational efficiency of the framework makes it capable of real-time prediction for large-scale networks. For links with large speed variations between days, prediction significantly outperforms the historical mean. Furthermore, prediction is reliable also for links with high proportions of missing data.

  • 8.
    Cebecauer, Matej
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning.
    Jenelius, Erik
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning.
    Burghout, Wilco
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning.
    Spatio-Temporal Partitioning of Large Urban Networks for Travel Time Prediction2018In: 2018 21ST INTERNATIONAL CONFERENCE ON INTELLIGENT TRANSPORTATION SYSTEMS (ITSC), IEEE , 2018, p. 1390-1395Conference paper (Refereed)
    Abstract [en]

    The paper explores the potential of spatiotemporal network partitioning for travel time prediction accuracy and computational costs in the context of large-scale urban road networks (including motorways/freeways, arterials and urban streets). Forecasting in this context is challenging due to the complexity, heterogeneity, noisy data, unexpected events and the size of the traffic network. The proposed spatio-temporal network partitioning methodology is versatile, and can be applied for any source of travel time data and multivariate travel time prediction method. A case study of Stockholm, Sweden considers a network exceeding 11,000 links and uses taxi probe data as the source of travel times data. To predict the travel times the Probabilistic Principal Component Analysis (PPCA) is used. Results show that the spatio-temporal network partitioning provides a more appropriate bias-variance tradeoff, and that prediction accuracy and computational costs are improved by considering the proper number of clusters towards robust large-scale travel time prediction.

  • 9.
    Fröidh, Oskar
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning.
    Berg, Mats
    KTH, School of Engineering Sciences (SCI), Aeronautical and Vehicle Engineering, Rail Vehicles.
    Framtida trafikeringskostnader och utveckling av persontågsparken: Slutrapport2019Report (Other academic)
    Abstract [sv]

    Syftet med projektet och rapporten är att beräkna och redovisa trafikeringskostnader med typtåg som underlag för ASEK 7.0 i Trafikverkets kommande nationella trafik- och infrastrukturplanering, och att göra en bedömning av vilka framtida tågtyper som kan rulla på spåren.

    Projektets resultat är främst val av typtåg och de trafikeringskostnader för typtågen som presenteras i rapporten.

    En äldre modell för att beräkna trafikeringskostnader i persontrafik har uppdaterats och vidareutvecklats vid KTH till Costmodel PT. Denna modell har använts att beräkna kostnader för framtida typtåg. I vissa fall saknas motsvarande tågtyp i Sverige idag och det har också varit svårt att få tillgång till aktuella data genom kommersiell sekretess. Trots det har den kalibrering som gjorts mot tillgängliga verkliga värden visat på en relativt god överensstämmelse.

  • 10.
    Högdahl, Johan
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning.
    A Simulation-Optimization Approach for Improved Robustness of Railway Timetables2019Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    The timetable is an essential part for the operations of railway traffic, and its quality is considered to have large impact on capacity utilization and reliability of the transport mode. The process of generating a timetable is most often a manual task with limited computer aid, and is known to be a complex planning problem due to inter-train dependencies.

    These inter-train dependencies makes it hard to manually generate feasible timetables, and also makes it hard to improve a given timetable as new conflicts and surprising effects easily can occur.

    As the demand for railway traffic is expected to continue grow, higher frequencies and more saturated timetables are required. However, in many European countries there is also an on-going public debate on the punctuality of the railway, which may worsen by increased capacity utilization. It is therefore also a need to increase the robustness of the services. This calls for increased precision of both the planning and the operation, which can be achieved with a higher degree of automation.

    The research in this thesis is aimed at improving the robustness of railway timetables by combining micro-simulation with mathematical optimization, two methods that today are used frequently by practitioners and researchers but rarely in combination. In this research a sequential approach based on simulating a given timetable and re-optimizing it to reduce the weighted sum of scheduled travel time and predicted average delay is proposed. The approach has generated promising results in simulation studies, in which it has been possible to substantially improve the punctuality and reduce the average delays by only increasing the advertised travel times slightly. Further, the results have also indicated a positive socio-economic benefit. This demonstrates the methods potential usefulness and motivates further research.

  • 11.
    Högdahl, Johan
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning.
    Delay Prediction with Flexible Train Order in a MILP Simulation-Optimization Approach for Railway Timetabling2019Conference paper (Refereed)
    Abstract [en]

    This paper considers the problem of minimizing travel times and maximizing travel time reliability, which are important socio-economic properties of a railway transport service, for a given set of departures on a double-track line. In this paper travel time reliability is measured as the average delay, and a delay prediction model for MILP timetable optimization is presented. The average delay prediction model takes into consideration time supplements, buffer times and propagation of delays in the railway network and is not restricted to a fixed order of the trains. Validation of the average delay prediction model, and an evaluation of the approach with combined simulation-optimization for improving railway timetables, are conducted by a simulation study on a part of the Swedish Southern Main Line. Results from the simulation study show that the average delays are reduced by up to approximately 40% and that the punctuality is improved by up to approximately 8%.

  • 12.
    Högdahl, Johan
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning.
    Bohlin, Markus
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning.
    Fröidh, Oskar
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning.
    A combined simulation-optimization approach for minimizing travel time and delays in railway timetables2019In: Transportation Research Part B: Methodological, ISSN 0191-2615, E-ISSN 1879-2367, Vol. 126, p. 192-212Article in journal (Refereed)
    Abstract [en]

    Minimal travel time and maximal reliability are two of the most important properties of a railway transportation service. This paper considers the problem of finding a timetable for a given set of departures that minimizes the weighted sum of scheduled travel time and expected delay, thereby capturing these two important socio-economic properties of a timetable. To accurately represent the complex secondary delays in operational railway traffic, an approach combining microscopic simulation and macroscopic timetable optimization is proposed. To predict the expected delay in the macroscopic timetable, a surrogate function is formulated, as well as a subproblem to calibrate the parameters in the model. In a set of computational experiments, the approach increased the socio-economic benefit by 2-5% and improved the punctuality by 8-25%.

  • 13.
    Högdahl, Johan
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning.
    Bohlin, Markus
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning. SICS Swedish ICT Västerås AB, Kopparbergsvägen 10, SE-722 13 Västerås, Sweden.
    Fröidh, Oskar
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning.
    Combining Optimization and Simulation to Improve Railway Timetable Robustness2017Conference paper (Refereed)
    Abstract [en]

    The Train Timetabling Problem (TTP) is the problem of finding the timetable that utilizes the infrastructure as efficient as possible, while satisfying market demands and operational constraints. As reliability is important to passengers it is important that timetables are robust. In this paper we propose a method that combines optimization and simulation to find the timetable that minimizes the travel times and maximizes the expected punctuality. The core method consists of iteratively re-optimizing a bi-objective mixed integer sequencing timetable model, where both planned travel time and simulated delays are taken into account. Each generated timetable is validated and re-evaluated using the micro-simulation tool RailSys. The advantage of the method is that it captures both the uncertainty of a timetable at the planning stage and the validity of the generated timetable. The method is evaluated on a unidirectional track section of the Western Main Line in Sweden and shows promising results for future research.

  • 14.
    Jegenberg, Minna
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning.
    Lundström, Kristina
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning.
    Utredning om ökad tillgänglighet och säkerhet för resenärer vid järnvägsstationer på mindre orter: En undersökning med en fallstudie i Fagersta som inkluderar resenärers och ansvariga aktörers syn på stationsmiljöer samt samarbetet mellan aktörerna2019Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    To increase the use of public transport and to increase the safety for the travelers, two aspects thatare included in the goals regarding the Swedish transport system, the design of railway stations isimportant. When planning stations, many stakeholders are involved and therefore there is a risk thatproblems may occur, especially in smaller municipalities where there might be a lack of resources.Moreover, it is the travelers’ needs that should be in focus when planning stations.This thesis was carried out with the objective to investigate measures to solve problems regardingthe travelers’ accessibility and safety at railway stations in Sweden. In addition, problems that mightoccur due to that many stakeholders are responsible for the station environment and whether thetravelers’ needs are reflected in the planning were investigated. To fulfill the objective, a case studywas performed at two small railway stations: Fagersta centralstation and Fagersta Norra. The casestudy included visual inspections of the stations, surveys among the travelers and interviews withresponsible stakeholders and with experts in these subjects.In the interviews with the stakeholders, many problems with the stations are mentioned but fewmeasures are suggested. In comparison between the answers from the stakeholders and the experts,the experts identified additional problems and suggested other measures and they should thereforebe consulted when planning station environments. In addition, additional problems were observedduring the visual inspections, mainly concerning conflicts between different traffic modes whichcould be both accessibility and safety problems. Based on this, visual inspections should beperformed when planning stations to observe problems that otherwise are forgotten.To increase the safety and the accessibility at the stations in Fagersta, measures to decrease thenumber of conflicts and their severity through e.g. hinders for vehicles and reorganization of thestation area are recommended. In the survey, the travelers pointed out the perceived safety and thewaiting area as important aspects at the stations. Since both of these aspects are insufficient,measures to improve these, through e.g. improved lighting and shelters, should be prioritized.The stakeholders’ perception of the travelers’ needs varied both between the stations and thestakeholders. Also, since the experts have a different focus, they do not observe the travelers’ needswhich makes it important to involve the travelers to find their actual needs. The stakeholders thattake initiative to consult the travelers however do not handle the station environments which meansthat no traveler dialogues are held about this at smaller stations. However, no clear connectionbetween whether the stakeholders keep regular dialogues with the travelers and if they have a clearview of the travelers’ needs were found. One benefit with consulting the travelers when planningstations could be that the responsible stakeholders receive guidance in prioritizing measures.Moreover, the shared responsibility for the station environments do not lead to that any part of thestation is forgotten in the assessment. Problems may however arise when objects are located inbetween different responsibility areas. Finally, the cooperation between stakeholders variesdepending on who are involved, and more problems might occur if private property owners areinvolved. A reorganization that suggests that one stakeholder has an overall responsibility over thestation could decrease these problems. The stakeholders that handles the traffic are positive towardsthis type of reorganization and the stakeholders that have a larger responsibility at the stations didnot give their view on this. The question regarding a reorganization needs further investigation.Key words: Accessibility, safety, railway station, stakeholder, traveler, cooperationEnglish title: An investigation regarding increased accessibility and safety for travelers at railwaystations in smaller municipalities – An evaluation with a case study in Fagersta that includes travelers’and responsible stakeholders’ view of the stations and the cooperation between stakeholders

  • 15.
    Jenelius, Erik
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning.
    Data-driven metro train crowding prediction based on real-time load data2019In: IEEE transactions on intelligent transportation systems (Print), ISSN 1524-9050, E-ISSN 1558-0016Article in journal (Refereed)
  • 16.
    Jin, Junchen
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning. Enjoyor Co Ltd, Hangzhou 310030, Zhejiang, Peoples R China..
    Ma, Xiaoliang
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning.
    A Multi-Objective Agent-Based Control Approach With Application in Intelligent Traffic Signal System2019In: IEEE transactions on intelligent transportation systems (Print), ISSN 1524-9050, E-ISSN 1558-0016, Vol. 20, no 10, p. 3900-3912Article in journal (Refereed)
    Abstract [en]

    Agent-based approaches have gained popularity in engineering applications, but its potential for advanced traffic controls has not been sufficiently explored. This paper presents a multi-agent framework that models traffic control instruments and their interactions with road traffic. A constrained Markov decision process (CMDP) model is used to represent agent decision making in the context of multi-objective policy goals, where the policy goal with the highest priority becomes the single optimization objective and the other goals are transformed as constraints. A reinforcement learning-based computational framework is developed for control applications. To implement the multi-objective decision model, a threshold lexicographic ordering method is introduced and integrated with the learning-based algorithm. Moreover, a two-stage hybrid framework is established to improve the learning efficiency of the model. While the proposed approach is potentially applicable for different road traffic operations, this paper applies the framework for traffic signal control in a network of Stockholm based on traffic simulation. The computational results show that the proposed control approach can handle a complex case of multiple policy requirements. Meanwhile, the agent-based intelligent control has shown superior performance when compared to other optimized signal control methods.

  • 17.
    Jin, Junchen
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning. Enjoyor Co Ltd, Hangzhou 310030, Zhejiang, Peoples R China.
    Ma, Xiaoliang
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning.
    A non-parametric Bayesian framework for traffic-state estimation at signalized intersections2019In: Information Sciences, ISSN 0020-0255, E-ISSN 1872-6291, Vol. 498, p. 21-40Article in journal (Refereed)
    Abstract [en]

    An accurate and practical traffic-state estimation (TSE) method for signalized intersections plays an important role in real-time operations to facilitate efficient traffic management. This paper presents a generalized modeling framework for estimating traffic states at signalized intersections. The framework is non-parametric and data-driven, without any requirement on explicit modeling of traffic flow. The Bayesian filter (BF) approach is the core of the framework and introduces a recursive state estimation process. The required transition and measurement models of the BFs are trained using Gaussian process (GP) regression models with respect to a historical dataset. In addition to the detailed derivation of the integration of BFs and GP regression models, an algorithm based on the extended Kalman filter is presented for real-time traffic estimation. The effectiveness of the proposed framework is demonstrated through several numerical experiments using data generated in microscopic traffic simulations. Both fixed-location data (i.e., loop detector) and mobile data (i.e., connected vehicle) are examined with the framework. As a result, the method shows good performance under the different traffic conditions in the experiment. In particular, the approach is suitable for short-term estimation, a challenging task in traffic control and operations.

  • 18.
    Langbroek, Joram H. M.
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment. KTH, School of Industrial Engineering and Management (ITM), Centres, Integrated Transport Research Lab, ITRL.
    Cebecauer, Matej
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning.
    Malmsten, Jon
    Franklin, Joel P.
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment.
    Susilo, Yusak O.
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment.
    Georén, Peter
    KTH, School of Industrial Engineering and Management (ITM), Centres, Integrated Transport Research Lab, ITRL. Solkompaniet Sverige AB, Vastbergavagen 4, S-12630 Hagersten, Sweden..
    Electric vehicle rental and electric vehicle adoption2019In: Research in Transportation Economics, ISSN 0739-8859, E-ISSN 1875-7979, Vol. 73, p. 72-82Article in journal (Refereed)
    Abstract [en]

    This case study describes the project Elbilsiandet (The Electric Vehicle Country) in Gotland, Sweden, where the island Gotland is made "ready for electric vehicles" by providing a network of charging infrastructure and electric vehicle rental during several summer seasons. The influence of the electric vehicle (EV) rental scheme on the process towards electric vehicle adoption is investigated using the Protection Motivation Theory (PMT) and the Transtheoretical Model of Change (TTM). Moreover, the travel patterns of electric rental cars are compared with those of conventional rental cars. The main results of this study are the following: Firstly, people renting an EV are on average closer to electric vehicle adoption than people renting a conventional vehicle. Secondly, people who rent an EV are at the time of rental associated with more positive attitudes towards EVs, have more knowledge about EVs and would feel more secure driving an EV. Thirdly, EV-rental does not seem to have a large additional effect on the stage-of-change towards EV-adoption of the participants. Lastly, the driving patterns of EVs do not seem to indicate serious limitations regarding driving distance, parking time and the destinations that have been visited, as compared to the driving patterns of conventional rental cars.

  • 19.
    Leffler, David
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning.
    Simulation based evaluation of flexible transit2019Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Transport authorities are faced with the challenge of making effective use of existing transportation infrastructure under increasing needs of transport accessibility, sustainability, and safety. The ongoing growth and adoption of shared mobility options, the anticipation of automated vehicles, and the increased availability of real-time data brought on with the developments of Intelligent Transport Systems, have all inspired many innovations in public transit design. The integration of these technologies in existing public transit holds great potential for operational planning and control, but is also notoriously difficult to evaluate. In the included papers, flexible operational policies that make use of real-time data and connected vehicles are developed and assessed through the extension of an existing public transit simulation framework, BusMezzo.

    Paper I explores the incorporation of flexibility in fixed urban transit via real-time short-turning, a fleet management strategy not often studied in a real-time context. In this paper, a decision rule for when and where a short-turn should occur based on predicted passenger costs is developed and evaluated in a case study of a bidirectional urban bus line in Stockholm, Sweden.

    Paper II focuses on the design and analysis of an automated feeder service. In this paper an extension of BusMezzo with a module for simulating a variety of flexible transit operations is presented. Estimated reductions in on-board crew costs with vehicle automation motivate a case study of two vehicle fleets where a fully demand-responsive operational policy is compared against fixed route and schedule operations.

  • 20.
    Leffler, David
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning.
    Jenelius, Erik
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning.
    Cats, Oded
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning. Delft University of Technology, Netherlands.
    Burghout, Wilco
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning.
    Simulation of fixed versus on-demand station-based feeder operationsManuscript (preprint) (Other academic)
    Abstract [en]

    Motivated by lower predicted operational costs, and opportunities for efficient real-time control, automated, centrally coordinated vehicles have in many studies shown great potential as a shared resource within public transit. One particular use case that has grown in popularity over recent years is the application of smaller, automated shuttles as an on-demand feeder to mass transit solution. To investigate differences in fixed versus on-demand operational policies, this paper discusses the operational design and analysis of an automated feeder solution. To this end, a simulation model of demand-responsive transit is developed and incorporated into the transit simulation model BusMezzo. An estimation of operational cost reductions with vehicle automation motivates the case study of two fleets that are deemed comparable with respect to service capacity and operational cost per hour. Results from simulation studies of varying levels of demand indicate that the on-demand policy reduces average total passenger travel times and, for the larger fleet, lowers average vehicle-kilometers traveled per passenger relative fixed service operations. Without achieving a competitive reduction in waiting times, however, on-demand coordination often underperforms with respect to level-of-service and reliability when compared with fixed service operations. When there is slack in fixed service capacity, the performance of the on-demand service outperforms the fixed service with respect to both level-of-service and vehicle utilization only for the lowest demand level tested and the smaller fleet. Average total system costs under on-demand operations improve, however, for the lowest demand levels and the larger fleet due to a reduction in vehicle-kilometers traveled relative a fixed service. When fixed service capacity is exceeded it is found that on-demand coordination outperforms fixed operations with respect to average level-of-service, vehicle-kilometers traveled, and total system costs. Furthermore, when planned service capacity is exceeded, it is found that total passenger waiting time is more equally distributed under on-demand operations relative to fixed.

  • 21.
    LIDSTRÖM OLSSON, DANIEL
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning.
    Inlandsbanan – befintliga spår, ny trafik: Förutsättningar för regional spårtrafik i glesbebyggda områden2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    When the car dependency grew under many decades in Sweden parts of the rail network was shutdown or got reduced traffic due to the diminishing demand for rail travel. The railway lines affectedwere primarily those in rural areas with an already low number of travellers. One of these linesthreatened to be shut down was the line called Inlandsbanan (Inland line). Inlandsbanan was savedby the municipalities located along the line who now manage the railway by a co-owned company.Since the railway became managed by the co-owned company the railway has mostly been used fortourist-oriented traffic and freight traffic.Today the conditions are different, the demand for rail travel has increased due to a general highertransport demand and an increased environmental awareness. This study has been carried out tofind out if there is possibility to re-establish regional rail traffic for passengers on Inlandsbanan.The study has been carried out using statistics of current travel volumes and inhabitants in thepopulation centres along the line. This data has been analysed with support from earlier studiesregarding regional rail traffic and public transport in rural areas. As an extra tool in the study asimulation program has been used to estimate the travel demand for the line.The study found that the current low speed on Inlandsbanan is the biggest obstacle for implementingan attractive regional rail service on the line. The train is too slow in comparison to the car andtherefore it is not able to gain any considerable share of the total amount of travellers. It is possibleto replace regional bus service at some parts of the line since the train has some minor time gaincompared to the current bus service and the train could also offer a higher level of comfort.

  • 22.
    LLORET CENDALES, KEVIN
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning.
    Robustness simulation ofbus crew schedules: Case Study Frihamnen Depot (Stockholm)2019Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This thesis develops a model aimed at predicting the performance of bus crew schedules and study their operational capacity to face disruptions, that is, its robustness. It is based on the relation among schedule deviation, passengers and slack times, considered as non-productive times before trips.Optimization of Public Transport is a challenge that main cities are facing since this type of transport is the backbone of mobility. New powerful versions of transport planning software are providing more optimal schedules to operators, therefore decreasing their costs, but increasing the risk of delays due to more gathered schedules that can cause fines and passengers’ dissatisfaction.A trade-off between production and fines costs is needed to find the optimal slack times. To reach that goal, the Frihamnen bus depot in Stockholm (Sweden) was selected as case study, having historical data of all their lines for last year. A regression model for schedule deviation was calculated which served to create a computer tool in Microsoft Excel, giving the possibility to checking the performance of new schedules based on that historical data.The results showed an inverse relation between schedule deviation and slack times. Moreover, short non-productive times before trips also mean high delays on departures. A positive output is that adding a stop of at least 10% of the total trip time, the first departure would be on time or 2 minutes late as maximum. Several software developers are applying similar studies to their products to keep optimizing bus schedules while taking an economic and social approach.

  • 23.
    Mitrovic, Branko
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning.
    The effects of emerging technologies in rail yards and intermodal terminals2019Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This paper analyzes the effects of emerging technologies in intermodal terminals and marshallingyards, based on “Intelligent Video Gate” project within the H2020 – Shift2Rail initiative. Projectaim is to initiate the next logical step to a higher level of automation in terminals and to reduce thelead-time needed for the identification/verification process of freight trains. Thesis projectexamine different emerging technologies that could be applied in intermodal terminal automationand possibilities for their application in different processes. Technologies considered in researchare RFID, cameras, scanners, sensors, GPS and scales. Marshalling yard as important freight nodeon railway network is included in research, where departing processes are examined, andtechnology proposed for automation of brake test procedures.Qualitative research is used as a method to investigate current processes in intermodal terminaland marshalling yards. This research included all the processes from train arrival to the terminal,through transshipment processes and train departure from the terminal. Research also conducteddifferent steps which Intermodal Transport Units go through during operations in intermodalterminal. Knowing processes enabled next step in qualitative research, finding the opportunitiesfor improvements in operations. Third step in qualitative research investigated different emergingtechnologies and as a result gave opportunities and obstacles behind each of technologies.Complementing findings from qualitative research, model simulation is performed, based onoperations in Malmö Kombiterminal. Intermodal terminal operations are simulated in Planimate®software. Addition to the qualitative research is finding the opportunities for improvements inmarshalling yards and proposing emerging technology that could be applied.Master thesis successfully accomplished the task of finding the effects of emerging technologiesin intermodal terminals and marshalling yards. The methodology concluded to be appropriate onefor building task solution. The project is viewed as a breakthrough in this domain but theexpectations for Intelligent Video Gate should stay realistic and proceeded carefully. Eliminationof brake test in marshalling yards is also very optimistic goal but should be followed by appropriatesafety rules and regulations. Simulation of complex systems such as intermodal terminals andmarshalling yards is the task that should be supported by accurate and detailed data, in order tokeep the model and results more realistic.

  • 24.
    Monte Malveira, Daniel
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning.
    Analysis of Walking and Route-Choice Behavior of Pedestrians inside Public Transfer Stations: A Study on how pedestrians behave in the approaching vicinity of level-change facilities,and how it affects their walking and route-choice behavior2019Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Pedestrian walking and choice behavior presented was first studied by Fruin in 1971, and since then a lot of research have been carried out in order to understand how humans move and what does make them make choices and obtain certain patterns. In relation to pedestrians, a significant bottleneck inside public stations evaluated by research are the level-change facilities, as Stair Walks and Escalators. The aim of this research is studying how pedestrian behave in the vicinity to stairways and escalators, and how does that affect pedestrian choice, speed and acceleration when choosing one of the two facilities. Also, with a need for more data on pedestrian traffic, further data collection is a big requirement to analyze their behavior and use as tools in future measures. At last, how to optimize the movement of pedestrians in relation to level changes, considering the effects of the movements observed. Two case studies were analysed, Stockholm Central Station and Uppsala Central Station.The study compares data collection methods, tracking methods and previous studies to better fit the scope of this research. The data is backed up from previous research and explains which method better fitted the options available. As a result, video data collection was chosen to collect the data, a semi-automatic tracking software called T-analyst was used to extract speed, trajectories and acceleration from the videos, and microsimulation modelling from VISSIM further investigated different design options to optimize the overall performance and improve travel time in the same area. The analysis found out that there was a possibility to increase the overall performance of the location in higher flow levels, where the most significant queues could be seen, since there was the possibility to achieve higher speeds by modifying the width and position of the stair walks, which allow for a smaller queue in both directions.

  • 25.
    Nelldal, Bo-Lennart
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning.
    Höghastighetsbanor: En investering för hållbart resande och godstrafik2019Report (Other academic)
    Abstract [sv]

    Syftet med att bygga nya stambanor är att öka den totala kapaciteten för gods- och persontrafik på järnväg, öka punktligheten och öka tillgängligheten genom korta restider. Det ger också förutsättningar för större regionala arbetsmarknader för ökat bostadsbyggande. Dessutom körs tågen helt elektriskt med möjlighet till att vara helt koldioxidneutrala.

    Trafiken med höghastighetståg är eldriven och fossilfri i Sverige från början. Bil och flyg drar flera gånger mer energi per resenär och km. Även om vägtrafiken elektrifieras kan den inte bli lika energieffektiv som spårtrafik eftersom den har högre rullmotstånd. Självkörande bilar kan inte korta restiderna och inte heller nämnvärt minska energianvändning, miljöbelastning och trängsel. Ännu mera gäller detta om elflyg skulle komma till stånd, vilket dock är inte troligt för stora flygplan på längre sträckor. Utsläppen från tågtrafik är en bråkdel av de från bil och flyg. Därför blir det en miljövinst när fler väljer tåg i stället för bil och flyg.Bygget av nya banor ger upphov till utsläpp som kompenseras när banan trafikeras genom minskade utsläpp från andra färdmedel.

    Trafikverket har gjort kalkyler av ”break-even” som sträcker sig från 27 år ner till 5 år. Fossilfri bil- och flygtrafik kan minska miljöeffekten bara under förutsättning att el, batterier eller biobränslen kan produceras i tillräcklig mängd och med små koldioxidutsläpp. Detta är osannolikt under överskådlig framtid. Om man inte bygger höghastighetsbanorna kommer resandet med bil och flyg öka. Då måste vägarna och flygplatserna byggas ut med ökade utsläpp som följd.

    Som vi pekat på tidigare så fungerar inte Trafikverkets prognosmodell i dag för att utvärdera stora banprojekt. Det är ett stort problem då stora investeringar diskuteras samtidigt som utmaningen med att minska trafikens klimatpåverkan blir alltmer akut. Det är inte bara de samhällsekonomiska kalkylerna som är viktiga. Prognosen i sig har också stor betydelse för planeringen av höghastighets-banorna och utbudet, för bedömning av möjligheterna till medfinansiering och för analys av behovet av utbyggda flygplatser och vägar.

  • 26.
    Nelldal, Bo-Lennart
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport Planning, Economics and Engineering.
    Andersson, Josef
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport Planning, Economics and Engineering.
    Fröidh, Oskar
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning.
    Resandeflöden på Sveriges järnvägsnät: Analys av utbud och efterfrågan på tågresor2018Report (Other academic)
    Abstract [sv]

    Genom den utbudsdatabas som KTH:s Järnvägsgrupp successivt har byggt upp finns en detaljerad beskrivning av hur utbudet av tåg, flyg och buss ser ut och också tidsseriedata för perioden 1990-2017. Däremot saknas detaljerad information av efterfrågan. Syftet med projektet ”Resandeflöden” är att ta fram data så att efterfrågan av tågtrafik kan beskrivas på ett bättre sätt.

    Genom att kombinera efterfrågedata med detaljerade utbudsdata och går det att få en bra bild över persontrafiken på järnväg i Sverige. Kompletterat med databaser över trafik- och fordon under en mätdag kan man beräkna nyckeltal och dygnsvärden kan skrivas upp till årsvärden. Tågtrafiken i Sverige kan då beskrivas t.ex. i form av antalet tågkilometer, personkilometer och beläggningsgrader för olika typer av trafik t.ex. lokaltrafik, regionaltrafik, Intercity-trafik och snabbtåg. I projektet visas att modellen har en god överensstämmelse mellan verkligt resande ner på linje- och produktnivå.

  • 27.
    ODHIAMBO, EVANS OTIENO
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning.
    Evaluation of Signal Optimization Software: Comparison of Optimal Signal Pans from TRANSYT and LinSig – A Case Study2019Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The design of traffic signal control plan is directly related to the level of traffic congestion experienced both at the junction level and the network particularly in urban areas. Ensuring signals are well designed is one of the most cost-effective ways of tackling urban congestion problems. Signal time plans are designed with the help of signal optimization models. Optimization can either be done for multiple or single objectives and is formulated as a problem of finding the appropriate cycle lengths, green splits, and offsets. Some of these objective functions include; better mobility, efficient energy use, and environmental sustainability. LinSig and TRANSYT are two of the most widely used traffic signal optimization tools in Sweden. Each of them has an inbuilt optimization function which differs from the other. LinSig optimizes based on delay or maximum reserve capacity while TRANSYT optimization is based on performance index (P.I) involving delay, progression, stops and fuel consumption.This thesis compared these optimization models through theoretical review and application to a case study in Norrköping. The theoretical review showed that both TRANSYT and LinSig have objective functions based on delay and its derivatives. The review also showed that these models suffer from the inability to accurately model block back as they are based on the assumption of vertical queuing of traffic at the stop line. Apart from these similarities, these two models also have significant variations with respect to modeling short congested sections of the network as well as modeling mixed traffic including different vehicle classes, pedestrians, and cyclists.From the case study, TRANSYT showed longer cycle time compared to LinSig in both scenarios as its optimization objectives include both delay and stops while LinSig accounts for only delay. The Allocation of phase green splits and individual junction delay was comparable for undersaturated junctions while congested network sections had significant differences. Total network delay was, however, less in LinSig compared to TRANSYT. This could be attributed to different modeling criteria for mixed traffic and congested network in addition to the fact that cyclists were not modeled in TRANSYT. VISSIM simulation of the two-signal time plans showed that network delay and queue lengths from TRANSYT signal timings are much less compared to LinSig time plans. A strong indication of better signal coordination.

  • 28.
    Ounsi, Karim
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning.
    Geographically Weighted Regression as a Predictive Tool for Station-Level Ridership: The Case of Stockholm2019Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This thesis studies a new regression method, Geographically Weighted Regression (GWR)to predict ridership at the station level for future stations. The case study of Stockholm’s blue lineis used as new stations will be built by 2030. This paper is written in English.Historically, linear regression methods, independent of the geographical location of theobservations, was and is still used as the Ordinary Least Square regression method. With the riseof GIS-softwares these last decades, geographically dependent regression can be used and previouspreliminary studies have shown a dependency between ridership and location of the station withinthe network.GWR equations for new stations are determined and used to predict their respectiveridership. GIS-data was collected using Geodata and Traffikverket (Traffic Authority) andridership as well as socio-economic related material for the base year of 2016 was used in order todetermine, first, significant variables from a group of candidate ones (Workers, number of buslines and type of change were chosen) and, second the OLS and GWR equations. Significances ofboth models were compared and the OLS equation was used in order to determine the hypotheticalridership of the new stations if they were present in 2016. GWR equations were then determinedusing these calculated ridership of these new stations. Having all GWR equations (each stationhaving its own equation), ridership was thus predicted for the new stations for 2030 usingassumptions and planned, programmed development around the stations (population, apartment tobe built…) and compared with the official predictions.The results show that the GWR method, generally, overpredicts ridership when comparedto the official predictions. Many reasons can explain this overprediction like the assumptions madewith regards to the number of buses as well as the method followed to calculate the number ofworkers around each station.Three main conclusions were drawn for this case study. One main conclusion, specific forthis study and two other, more general, conclusions were deduced from this study. First, GWR isa good predicting tool for future stations that are close to most currently available stations. Second,GWR is a good predicting method for stations where limited changes in the future environmentwill occur.

  • 29.
    Peftitsi, Soumela
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning.
    Simulation and Evaluation of Urban Rail On-board Crowding2019Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    As travel demand grows in many metropolitan areas, overcrowding in public transport systems has become a major issue. Crowding distribution can be highly uneven over station platforms and multi-car transit vehicles. This implies that cars are not equally utilized and thus, passengers perceive on-board crowding higher. Furthermore, there are higher fleet requirements to serve the demand, leading to higher operating costs. Public transport operators' main concern is to reduce on-board crowding effects through investments. Thus, there is a need to thoroughly understand how passengers are distributed among individual cars and evaluate on-board crowding in a more realistic way, by considering that passenger distribution over vehicles is not even. 

    Paper I explores the utilization of automated public transport data to analyze passengers' boarding behavior and investigate the trade-offs between crowding and walking when passengers make car boarding choices. The framework proposed in this paper is applied in a case study of a line segment of Stockholm metro network. In crowded conditions, passengers are found to make trade-offs, increase walking to avoid in-vehicle crowding, when choosing a train car. 

    Paper II focuses on the extension of an existing public transit operations and assignment model, BusMezzo, to allow modelling of crowding in individual cars of a multi-car vehicle. The simulation framework is applied in a case study in Stockholm metro network, evaluating the effects of variations in demand and station layout on the distribution of passengers over vehicles. Increased demand results in a more even passenger distribution at the most crowded stations. This is due to less remaining capacity that leads to low flexibility of how passengers are distributed among train cars. The closure of a popular access point at a selected station leads to more evenly loaded trains and lower perceived in-vehicle travel times per passenger.

  • 30.
    Peftitsi, Soumela
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning.
    Jenelius, Erik
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning. KTH, School of Architecture and the Built Environment (ABE), Centres, Centre for Transport Studies, CTS.
    Cats, Oded
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning. KTH, School of Architecture and the Built Environment (ABE), Centres, Centre for Traffic Research, CTR. KTH, School of Architecture and the Built Environment (ABE), Centres, Centre for Transport Studies, CTS.
    Determinants of passengers' metro car choice revealed through automated data sources: A Stockholm case studyIn: Article in journal (Refereed)
    Abstract [en]

    We propose a methodology based on multiple automated data sources for evaluating the effects of station layout, arriving traveler flows, and platform and on-board crowding on the distribution of boarding passengers between individual cars of metro trains. The methodology is applied to a case study for a sequence of stations in the Stockholm metro network. While train car loads at the analyzed stations are generally skewed towards the leading cars, results indicate that a crowded front car of the arriving train is associated with increasing boarding shares of the middle car. Moreover, higher platform crowding is found to have a positive effect on the boarding share of the middle cars. These findings suggest that passengers opt for less crowded train cars in crowded situations, trading-off walking and in-vehicle crowding while waiting and riding. We find that the boarding car distribution is also affected by the locations of platform access points and the distribution of entering traveler flows. These insights may be used by transit planners and operators to increase the understanding of how passengers behave under varying crowding conditions, identify the factors that affect travelers' choice of metro car and eventually reduce experienced on-board crowding and increase the capacity utilization of the trains through investments in infrastructure or operational interventions.

  • 31.
    Peftitsi, Soumela
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning.
    Jenelius, Erik
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning. KTH, School of Architecture and the Built Environment (ABE), Centres, Centre for Transport Studies, CTS.
    Cats, Oded
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning. KTH, School of Architecture and the Built Environment (ABE), Centres, Centre for Traffic Research, CTR. KTH, School of Architecture and the Built Environment (ABE), Centres, Centre for Transport Studies, CTS.
    Evaluating crowding in individual train cars using a dynamic transit assignment modelIn: Article in journal (Refereed)
    Abstract [en]

    Crowding is one of the major issues of public transport systems and has many negative effects for both users and operators. Passengers can be highly unevenly distributed between individual cars of a train even when the total passenger load exceeds the practical capacity.

    Transit assignment models (TAM) are widely used for describing and evaluating crowding in the vehicle. However, these models usually do not capture how passengers are distributed across the vehicle. To this end, this study introduced to an agent-based simulation model the capability to analyze the effective capacity utilization of the train, by considering passengers' distribution among individual train cars.

    The developed model is validated and applied to a case study for the Stockholm metro network, evaluating three scenarios. The findings suggest that an increase in peak hour demand leads to a more even passenger distribution among individual cars upon train departure from the most crowded stops, where passengers' choices are less flexible. The closure of the most popular entrance point at Danderyds sjukhus stop, where passenger distribution is highly skewed, is found to lead to lower crowding unevenness at the specific stop but also upon departure from the downstream stops.

  • 32.
    Rickardsson, Johan
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning.
    Olofsson, Josefin
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning.
    Att utforma en gång- och cykelbana: En analys av utrymmesbehovet på ytbegränsade gång- och cykelbanor i Stockholm2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Region Stockholm recently set a goal to highly increase the bicycle traffic share the comingdecade. Bicycles as a means of transport has grown in popularity and current trends showa steady yearly increase. The ambitiously set goal puts high demands on the currentpedestrian and bicycle paths in the city. More often than not, pedestrians and cyclists sharethe same space, and thus creating a source for conflicts. Accident statistics show these twogroups are particularily vulnerable, and as a result there is a considerable need for gooddesign of pedestrian and bicycle paths.The aims of this study are to examine the current guiding manuals for design; to developand use a method of analysing the interactions between pedestrians and cyclists; andfinally to explore how the design recommendations from the guiding manuals are followedthroughout routes in the city. The study’s purpose could be summarised as investigatingwhich widths of the pedestrian and bicycle paths result in the smallest amount of conflictsbetween the two groups. The project is split into one part literature study, one part fieldstudy.The literature study scrutinises the guiding manuals for design published by RegionStockholm, The Swedish Transport Administration ( Trafikverket ), The City of Stockholm,and The Swedish Authority of Local Authorities and Regions ( SKL ). Other works, such asreports and papers, or guiding design manuals from Denmark, a country in the frontier ofbicycle planning, are included in the analysis. In the field study, nine suitable locations inStockholm are chosen for data collection. The number of interactions and conflictsbetween pedestrians and cyclists are analysed for each location with intention of findingconnections between the conflicts and the design of the pedestrian and bicycle paths.Ultimately the study concludes that pedestrian paths should have a minimum width of 210centimetres. A satisfying interval of 220 - 230 centimetres is shown to be sufficient as thewidth of the bicycle path, which in total adds up to about 4.3 metres.

  • 33. Saadallah, Amal
    Sousa, Ricardo
    Khiari, Jihed
    Jenelius, Erik
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning. KTH, School of Architecture and the Built Environment (ABE), Centres, Centre for Transport Studies, CTS.
    BRIGHT - Drift-Aware Demand Predictions for Taxi Networks2018In: IEEE Transactions on Knowledge and Data Engineering, ISSN 1041-4347, E-ISSN 1558-2191Article in journal (Refereed)
    Abstract [en]

    Massive data broadcast by GPS-equipped vehicles provide unprecedented opportunities. One of the main tasks in order to optimize our transportation networks is to build data-driven real-time decision support systems. However, the dynamic environments where the networks operate disallow the traditional assumptions required to put in practice many off-the-shelf supervised learning algorithms, such as finite training sets or stationary distributions. In this paper, we propose BRIGHT: a drift-aware supervised learning framework to predict demand quantities. BRIGHT aims to provide accurate predictions for short-term horizons through a creative ensemble of time series analysis methods that handles distinct types of concept drift. By selecting neighborhoods dynamically, BRIGHT reduces the likelihood of overfitting. By ensuring diversity among the base learners, BRIGHT ensures a high reduction of variance while keeping bias stable. Experiments were conducted using three large-scale heterogeneous real-world transportation networks in Porto (Portugal), Shanghai (China) and Stockholm (Sweden), as well as controlled experiments using synthetic data where multiple distinct drifts were artificially induced. The obtained results illustrate the advantages of BRIGHT in relation to state-of-the-art methods for this task. 

  • 34.
    Stanislawska, Cornelia
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning.
    Intermodala godstransporter i Sverige: En kunskapsöversikt av hinder och tekniska lösningar2019Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    In 2018, the Swedish Government developed a new freight transport strategy. The strategyemphasizes that climate-friendly modes of transportation should be used to a greater extentfor freight transport. Intermodal transport, where unit-ready goods are transported with acombination of transportation modes, has been proposed as one of the solutions. As part of thework with the new strategy, the Government has commissioned the Swedish TransportAdministration to investigate what obstacles there are to intermodal transport, and toinvestigate whether there are any technical solutions or innovations that can increase the useof intermodality. The purpose and aim of this work have been to support the SwedishTransport Administration with their assignment from the Government by compiling thebarriers and technology of intermodality.By conducting a thorough examination of previous research and reports of intermodality,mainly railway and maritime transport, together with an in-depth interview with a Professor inthe subject, several different angles and views on the subject have been gathered.The results show that there are several areas in the industry where problems have beenidentified. Regulations and organizational structure, the limited area of competition andtransfer potential, the quality of the infrastructure and the location and costs of the terminalsare the main barriers to intermodality in Sweden today.It is possible to use technical solutions or other innovations to help minimizing one of theobstacles, the location of terminals and costs. These can for example be horizontaltranshipment technology, autonomous transhipment technology, IT systems and simulationtools or innovative network structure and location of terminals.Although there are plenty of ideas of new technology and solutions, few of these come intoproduction. One of the problems is the users/company’s uncertainty about investing inprojects that they do not know will be profitable. Standardized dimensions also present anobstacle to the technology which then must be adapted to current dimensions and strengthrequirements. There must also be a policy at international, national and local level with acommon goal that encourages the use of new technology.Most of the obstacles identified cannot be solved quickly and easily by introducing newtechnology. Instead, authorities and actors in the industry need to review their priorities andcommunicate with each other in order to come up with common solutions.

  • 35.
    Söder, Isabelle
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning.
    Modelling Effects of Car Sharing on Travel Behaviour2019Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Shared modes of transport, including car sharing, have been pointed out as one way of reducing private car use, contributing to an efficient transportation system that fulfills societal and environmental goals.Previous studies show that a share of car sharing users sells or refrains from acquire a new vehicle, when entering car sharing. Also, on average, car sharing has been shown to reduce Vehicle Kilometers Traveled (VKT) by car among the users.This study is conducted in three parts. First, a literature review of the effects of car sharing on travel behavior and car ownership is presented. Second, an implementation of car sharing in an existing transport model is described and the estimated effects are analyzed in relation to the findings in the literature study. In the final part, the car sharing module is reformulated to model a station-based car sharing system, where the distances to car sharing vehicles are used to distribute the effect of car sharing on car ownership spatially.This work contributes to the field by connecting the results from previous research about car sharing with practical transport modelling. The model of the station-based car sharing system is a useful tool for planners when considering the placement of car sharing stations. Also, this study provides an updated literature review covering findings of the effects of car sharing on travel behaviour and car ownership.Keywords: car sharing, station-based car sharing, travel demand modelling, vehicle ownership modelling, four-step model

  • 36.
    Urtasun López, Marc
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning.
    Analysis of Autonomous Buses impact on transportation between Stockholm’s universities2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The city of Stockholm is developing fast and its population is strongly growing,new solutions for urban mobility must be found. Implementations in the publictransport network are needed and the use of automated buses is a present topicfor efficient and sustainable transportation. The Vetenskapsstaden area has threeof the main university campus coexisting, this leads to a generation of campusto-campus trips which creates an impact in the Stockholm’s public transport.The unique environment and singular users arise the aim to execute a potentialsolution to release ridership from the public transport network. This thesisanalyzes and evaluates whether a new automated bus line is needed or not inthe studied area. A cost model will study the proposed solutions through therated decision variables: frequency and capacity, commercial speed and differentrates of demand. The relative efficiency of the proposed implementations isstudied compared with the costs of the current public transport modes used inthe area. Numerical analysis and results are given for two different scenarios:implementing one bus line connecting the three campuses or three lines betweencampuses. The former scenario shows to be more sensitive to the studied variablesand presents higher costs whereas the second-option costs have a robust responseand lower overall price evaluation. For both infrastructure models, the rateof demand is crucial to evaluate the advantages of a potential solution. Theestablished method and criteria contributes to a better understanding of theimpact of autonomous buses to low-demand analytic models.

  • 37.
    Yang, Wentao
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning.
    Simulation-based evaluation of a new floating vehicle speeding detection method2019Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Driving too fast is one of the major causes that lead to road crashes. A new speed enforcement management method based on autonomous vehicle technologies has the potential to enhance the speed limit compliance and improve traffic safety. This paper investigates the performance of this method in the detection stage under different scenarios. 27 scenarios are generated using microscopic simulation in VISSIM to collect performance data of this method. Analysis of variance (ANOVA) is used to examine the performance difference between scenarios, including the detectable distance, the number of lanes, the speed of the measuring vehicle, the flow of the traffic, the desired average speed of the traffic, and the desired speed variance of the traffic. As a result, the influences of the factors on the performance of the method are distinguished. The detectable distance, the speed of the measuring vehicle and the flow of traffic have non-linear effects on the number of detected speeding vehicles. The measuring vehicle can interact with more speeding vehicles when the average speed of the traffic is high and the speed variance is small.

  • 38.
    Zhang, Wei
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning.
    Planning and evaluation of autonomous vehicles in freight and public transport services2019Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The introduction of automation technology in transport systems brings both opportunities and challenges. The direct benefits of automation technology are obvious, for instance, reduced marginal driving cost, improved energy efficiency and increased safety. However, factors such as additional vehicle acquisition cost might hinder the implementation of autonomous vehicles, especially in the early stages when mass production is not realized yet. Besides, some benefits require large-scale applications or cooperation among multiple vehicles, while the low market penetration rate of autonomous vehicles may make system-specific benefits insignificant. Without proper planning and operation schemes, the advantages of automation technology can be cancelled out by its disadvantages. Given that the advantages of individual autonomous vehicles have been extensively explored, it is necessary to estimate the efficiency of transport systems involving autonomous vehicles. This thesis intends to solve the operation problem of autonomous vehicles in freight and public transport systems, focusing on system cost analysis.

    In freight transport, semi-autonomous truck platooning is a promising way to reduce fuel consumption. By instructing vehicles to form groups and drive together closely, the trailing vehicles experience reduced air resistance from the leading vehicle, and thus less fuel consumption. However, in practice, freight transport companies should also take time windows and transport reliability into consideration. The study answers the questions whether platoons should be formed and how significant can the savings be, considering driving cost, predefined time windows, travel time uncertainty and fuel cost. System optimization techniques, including stochastic optimization and mixed-integer linear programming, are adopted to minimize the total cost.

    In public transport, autonomous buses are assumed to save on-board crew cost, partially or fully. Similar with truck platoons, semi-autonomous buses can also form bus platoons for the purpose of eliminating the drivers from trailing buses. By contrast, fully autonomous buses are completely driverless and operates individually like conventional buses. To investigate the efficiency of autonomous buses, we compare the total cost of autonomous buses with conventional buses, where both passengers’ cost and service provider’s cost are modelled. In a general trunk-and-branches network connecting city center and suburbs, both fully autonomous bus and semi-autonomous bus systems are assessed. On a simple highly demanded corridor where demand varies during peak and off-peak hours, semi-autonomous bus platoons can be used as trains by extending its capacity in peak hours. Application of semi-autonomous vehicles are considered in traditional bus transit and BRT, by comparing with its conventional opponents.

  • 39.
    Zhang, Wei
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning.
    Jenelius, Erik
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning.
    Badia, Hugo
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning.
    Efficiency of connected semi-autonomous platooning bus services in high-demand transit corridorsManuscript (preprint) (Other academic)
    Abstract [en]

    The paper investigates the efficiency of serving high demand transit corridors with connected semi-autonomous busplatoons in both bus and BRT services. Platooning could make it possible to provide higher capacity than with conventionalbuses by forming virtual long buses out of multiple smaller vehicles, which could be particularly relevant inscenarios with large variation in demand between peak and off-peak hours. The problem is formulated as a constrainedoptimization problem to minimize total system cost, which includes waiting cost, access cost, riding cost, operatingcost and capital cost. For single period with fixed demand, both analytical solutions and numerical examples areprovided. Sensitivity analysis is carried out with regard to demand levels and capacity upper bound. The problemis generalized to a two-period problem considering peak and off-peak demand. Numerical results are provided withsensitivity analysis regarding average demand level and ratio of peak/off-peak demand. Furthermore, the impact of alower bound on service headway is investigated. The result shows that semi-autonomous vehicle platooning is competitivein medium and high demand scenarios, with the potential of reduced users’ cost and operator’s operating costat the expense of additional rolling stock cost. The minimum headway, restricted vehicle size, and higher demandratio all make semi-autonomous platooning more advantageous.

1 - 39 of 39
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