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  • 1.
    Bergquist, Markus
    et al.
    Trafikverket/Academic Work.
    Bernhardsson, Viktor
    Swedish National Road and Transport Research Institute, Society, environment and transport, Traffic analysis and logistics.
    Rosklint, Emma
    Trafikverket.
    Representation of the Swedish transport and logistics system in Samgods v. 1.1.2016Report (Other academic)
    Abstract [en]

    The national model for freight transportation in Sweden is called Samgods. The purpose of the model is to provide a tool for forecasting and planning of the transport system. Samgods can be used in policy analysis such as studying the effects of a tax change or a change in transport regulation etc. The aim of this report is to give an overview of how the Swedish transport and logistics system is represented in the Samgods model. Samgods consists of several parts, where the logistics module is the core of the model system. This report describes the setup data needed to run version 1.1 of the Samgods model.

    The 35 commodity groups used in the model are based on the 24 groups in the European NST/R- nomenclature. Some commodities are further divided due to their importance for Swedish freight transport and varying logistic properties. Transport demand is described with commodity specific demand matrices for 464 administrative zones inside and outside Sweden. The commodity specific P, C or W zones are split into sub-cells that include firms. The method used to generate the firm to firm flows is to divide the firms at the origin zone and destination zone into three categories according to size.

    A range of vehicle and vessel types are used to reflect scale advantages in transporting operations, including loading and unloading. The Samgods model uses six vehicle types for road, 10 for rail, 22 for sea and one for air. In total, 98 pre-defined transport chains are used.

    Infrastructure networks are used to generate the level of service (LOS)-matrix data for each vehicle/vessel type providing transport time and, distance and network related infrastructure charges. The logistics costs consist of transport costs (vehicle type specific link costs and node costs) and non-transport costs (commodity specific order costs, storage costs and capital costs in inventory as well as capital costs in transit). For each commodity it is assumed that either the overall logistics costs are optimized or the transport costs are minimized. The model generates a huge amount of output at different levels. All the output files generated are described in the last chapter of this report.

  • 2.
    Bernhardsson, Viktor
    Swedish National Road and Transport Research Institute, Society, environment and transport, Traffic analysis and logistics.
    Genomlysning av VQ-samband för tvåfältsvägar: Metodförslag till förbättrad klassificering2018Report (Other academic)
    Abstract [sv]

    Trafikverkets hastighetsflödessamband (VQ-samband) redovisar reshastighet på väglänkar för fordonstyperna personbil (pb), lastbil/buss utan släp (lbu) och lastbilar med släp (lbs) som funktion av totalt trafikflöde. VQ-sambanden delas in i olika klasser baserat på vägtyp, hastighetsgräns etc. och sambanden uppdateras kontinuerligt (vanligtvis i fyraårsintervaller) baserat på nya mätdata.

    Vid den senaste revideringen (2017) visade det sig vara svårt att utifrån tillgänglig information i Nationella vägdatabasen (NVDB) bestämma lämplig VQ-klass. Detta eftersom data i NVDB huvudsak beskriver hur vägen ser ut och inte hur den fungerar ur ett trafikföringsperspektiv. För vissa vägtyper är den nuvarande klassindelningen inte längre lämplig. Exempelvis, för tvåfältsvägar tillämpar Trafikverket idag en uppdelning baserat på vägbredd, men skillnaden i hastighet mellan olika vägbredder verkar mer troligt bero på vilken typ av trafik (kortväga/långväga) som trafikerar breda respektive normalbreda vägar.

    Syftet med detta uppdrag var att genomföra en genomlysning av nuvarande indelning av vägklasser och föreslå en ny vägklassindelning för tvåfältsvägar. I nuläget tillämpas följande förklaringsvariabler för hastighetssamband på tvåfältsvägar:

    • Hastighetsgräns
    • Vägbredd
    • Siktklass

    Först genomfördes en översyn av lämpliga datakällor att inkludera vid bedömning av lämpliga förklaringsvariabler. Vid den senaste revideringen av VQ-sambanden tillämpades enbart data från Trafikverkets trafikmätningssystem (TMS) som synkats mot NVDB. Kompletterande mätningar i form av Trafikverkets mätningar för beräkning av hastighetsindex samt synkning mot databasen Pavement Management Systems (PMSv3) bör kunna tillföra relevant information.

    Baserat på erfarenhet och tillgängliga datakällor, gjordes en översyn av vilka faktorer som antas påverka trafikföringen på tvåfältsvägar. En bruttolista med faktorer identifierades, vilka senare användes som grund för att skapa en enkät som distribuerades till en referensgrupp, beståendes av sakkunniga inom branschen. Referensgruppen bedömde vilka faktorer som ansågs påverka trafikföringen på tvåfältsvägar i störst utsträckning, samt bidrog med direkta förslag till lämpliga förklaringsvariabler.Baserat på resultaten från enkätundersökningen identifierades ett antal förslag på lämpliga förklaringsvariabler, samt hur de skulle kunna extraheras från tillgängliga data. Följande förklaringsvariabler föreslås för hastighetsflödessamband på tvåfältsvägar:

    • Hastighetsgräns
    • Linjeföring
    • Trafiktyp
    • Vägutformning
    • Trafiksammansättning

    Förslagsvis utvärderas ett antal givna kombinationer av dessa förklaringsvariabler baserat på spridningen i datamaterialet för den aktuella grupperingen av förklaringsvariabler. Regressionsanalys kan tillämpas för att bedöma lämplig gruppering.

  • 3.
    Bernhardsson, Viktor
    Swedish National Road and Transport Research Institute, Society, environment and transport, Traffic analysis and logistics.
    Trafiksimulering av E20 Ribbingsberg–Vara: En simuleringsstudie av framkomlighet för en mötesfri utformning av E202017Report (Other academic)
    Abstract [en]

    The part of road E20 between Ribbingsberg and Vara in Sweden will be converted from a two-lane rural road with speed limit 80 kilometers per hour into an oncoming separated highway with speed limit 100 kilometer per hour. The suggested design of the oncoming separated highway includes sections of 1+1 and 2+2 lanes with varying lengths between 1.6 and 3.2 kilometers. Due to the current high level of traffic demand in combination with high levels of trucks, the traffic performance at the suggested design could be questioned. In order to evaluate traffic performance, a traffic simulation study has been performed for the peak hour during a typical weekday. The study includes three different scenarios of traffic demand, representing levels of year 2015, 2025 and 2045. Simulations are performed using the microscopic simulation model RuTSim (Rural road Traffic Simulator), developed by VTI and customized for rural traffic. The model is calibrated using measurements from the actual road stretch in combination with data from the adjacent oncoming separated highway with speed limit 100 kilometers per hour between Vara and Skara. Simulation of year 2045 generates average speed for cars of 94 kilometers per hour. Sensitivity analysis of limited overtaking willingness results in average speed as minimum 92 kilometers per hour.

    This means that the traffic performance fulfills the condition according to Trafikverkets former requirement that the average speed for cars should not be less than 10 kilometers per hour below the speed limit (100 kilometer per hour). The share of constrained vehicles also supports the conclusion of a design with satisfying traffic performance. It should though be mentioned that the lengths of the twolane segments within the suggested design exceeds the recommendations according to Trafikverket

  • 4.
    Bernhardsson, Viktor
    et al.
    Swedish National Road and Transport Research Institute, Society, environment and transport, Traffic analysis and logistics.
    Olstam, Johan
    Swedish National Road and Transport Research Institute, Society, environment and transport, Traffic analysis and logistics.
    Effektiva omkörningsfält på 2+1-vägar: trafiksimuleringar av olika utformningsalternativ ur ett framkomlighetsperspektiv2017Report (Other academic)
    Abstract [en]

    The traffic performance at oncoming lane separated highways with alternating dedicated overtaking lanes (so called 2+1 roads), is dependent on the share of two lane segments (also known as the share of overtaking length). In order to maximize utilization and traffic performance, the configuration of the overtaking lanes should be designed to avoid congestion and delays. Short overtaking lanes implies limited time of queue discharge, but gives frequently recurring possibilities to overtake. Increased lengths of overtaking lanes imply the possibility to overtake several vehicles per overtaking lane, but increases the risk of catching up slower vehicles since the configuration also results in increased lengths of one lane segments.

    This report presents a traffic simulation study of how different configurations affects the throughput at 2+1 roads. The results indicate that overtaking lanes between 1 050 and 1 400 meters result in shortest travel time. However, the differences are small (~0.4 seconds/km) and not statistically significant. Thus, the benefit of optimizing the configuration in terms of throughput could be questioned. Based on the results, it becomes reasonable to question the concept of designing 2+1 roads with long overtaking lengths (which corresponds to the recommendations from the Swedish Transport Administration (Trafikverket)). The major risk of catching up a slower vehicle at the one lane segments obviously affects the travel time.

  • 5.
    Grumert, Ellen
    et al.
    Swedish National Road and Transport Research Institute, Society, environment and transport, Traffic analysis and logistics.
    Bernhardsson, Viktor
    Swedish National Road and Transport Research Institute, Society, environment and transport, Traffic analysis and logistics.
    Ekström, Joakim
    Linköpings universitet.
    Gundlegård, David
    Linköpings universitet.
    Ringdahl, Rasmus
    Linköpings universitet.
    Tapani, Andreas
    Swedish National Road and Transport Research Institute, Society, environment and transport, Traffic analysis and logistics.
    Variabla hastighetsgränser för Stockholms motorvägsnät: effekter av alternativa algoritmer och möjligheter till styrning genom estimerade trafiktillstånd2019Report (Other academic)
    Abstract [en]

    Variable speed limits are commonly used on Stockholm’s urban motorways, and it is part of the Stockholm Motorway Control System (MCS). The goal of today’s system is to reduce the risk of accidents during congested conditions, traffic jams etc. This is done by updating the speed limits shown on variable message signs based on a measured average speed at fixed detectors. As the demand for travel in Stockholm during peak-hours exceeds the available capacity in the road network, the need for an efficient traffic system is high. Variable speed limit systems have the possibility to contribute to increased efficiency, but since today’s system aims to increase safety, effects that lead to increased efficiency are limited. Further, in todays’ variable speed limit systems there are a large dependency of precise and available measurements from stationary detectors to be able to display speed limits that reflects the current traffic conditions. The purpose of this report is to investigate alternative control algorithms to decide on the variable speed limits to be displayed at variable message signs on the urban motorway of Stockholm.

    The goal is to increase efficiency compared to today's system. Two different road stretches with different complexity and different traffic conditions, resulting in two different types of congestion, are studied. Thereby, the studied control algorithms on the two road stretches are chosen based on the possibility of solving a specific problematic traffic situation in the best way. Hence, the studied control algorithms might differ for the two road stretches. Furthermore, for one of the roads stretches it is investigated if estimation of the traffic state can be used as input to the control algorithm as a complement to missing and erogenous measurements from stationary detectors in order to improve the calculations of the variable speed limits. The control algorithms are evaluated with microscopic traffic simulation and the method developed in the project Mobile Millenium Stockholm (MMS), using a macroscopic traffic flow model together with a Kalman filter, is used for estimation of the traffic state.

  • 6.
    Karlsson, Rune
    et al.
    Swedish National Road and Transport Research Institute, Society, environment and transport, Traffic analysis and logistics.
    Bernhardsson, Viktor
    Swedish National Road and Transport Research Institute, Society, environment and transport, Traffic analysis and logistics.
    Calibration report: Samgods version 1.1.12018Report (Other academic)
    Abstract [en]

    The Samgods model is used for describing and analyzing the Swedish goods transportation system on an overall national level. The Swedish Transport Administration is responsible for its maintenance and development. The current version 1.1, from 1 April 2016, is planned to be replaced by version 1.1.1 in April 2018.

    In this report, changes made from version 1.1 to 1.1.1 in the model are described, as well as the effects these changes have on the more important output from the model. In version 1.1.1, new cost input data has necessitated a recalibration of the model and new values for the calibration parameters have been produced. In principle, the same types of calibration parameters are used in the new version as in the previous one. Particular focus is on the deviations between model output and the statistical data being used as calibration targets. Comparisons of these deviations between versions 1.1 and 1.1.1 are also presented.

  • 7.
    Nitsche, Philippe
    et al.
    Austrian Institute of Technology (AIT).
    Olstam, Johan
    Swedish National Road and Transport Research Institute, Society, environment and transport, Traffic analysis and logistics.
    Taylor, Nicholas
    Transport Research Laboratories (TRL).
    Reinthaler, Martin
    Austrian Institute of Technology (AIT).
    Ponweiser, Wolfgang
    Austrian Institute of Technology (AIT).
    Bernhardsson, Viktor
    Swedish National Road and Transport Research Institute, Society, environment and transport, Traffic analysis and logistics.
    Mocanu, ISabel
    Austrian Institute of Technology (AIT).
    Uittenbogaard, Jeroen
    Netherlands Organisation for Applied Scientific Research (TNO).
    van Dam, Esra
    Netherlands Organisation for Applied Scientific Research (TNO).
    Pro-active Management of Traffic Incidents Using Novel Technologies2016In: Transportation Research Procedia, 2016, Vol. 14, p. 3360-3369Conference paper (Refereed)
    Abstract [en]

    This paper presents the results of the assessment phase of the project PRIMA (Pro-Active Incident Management), where the benefits, costs and risks of novel traffic incident management techniques are investigated. The project targets the enhancement of current state-of-the-art measures for handling incidents, i.e. road accidents, breakdowns and congestion, by recommending proactive techniques. To this end, modern technologies such as eCall, C2X or xFCD are assessed in terms of their potential to optimize the overall incident duration and response. Results are derived from a scenario-based assessment methodology involving macroscopic traffic simulations, traffic performance calculations and cost-benefit analysis. The work presented in this paper is being followed up by the development of practical guidelines and recommendations for traffic managers of motorways and primary roads.

  • 8.
    Olstam, Johan
    et al.
    Swedish National Road and Transport Research Institute, Society, environment and transport, Traffic analysis and logistics.
    Bernhardsson, Viktor
    Swedish National Road and Transport Research Institute, Society, environment and transport, Traffic analysis and logistics.
    Hastighetsflödessamband för svenska typvägar: Förslag till reviderade samband baserat på trafikmätningar från 2012–20152017Report (Other academic)
    Abstract [en]

    Speed-flow relationships are an important part of the Swedish Transport Administration (Trafikverket) model for evaluation of effects of road facilities (the EVA model). This report present suggestions for new speed-flow relationships for motorways (MV), low standard motorways (4F), oncoming lane separated highways with grade separated intersections (MML), oncoming separated highways with at grade intersections (MLV), and two-lane highways. The suggestions are based on data from measurements using the Swedish Transport Administration’s traffic measurement system TMS in combination with model calculations. The TMS data have, for each road category, been quality checked, processed and analysed. The data material is presented as speed-flow diagrams for passenger cars, buses and trucks without trailer, and trucks with trailers. A comparison of the current speed-flow relationships and the TMS-measurements was then conducted for each road category, and if needed a suggestion for a revision was presented. The most significant changes from last revision from 2013 are: average free flow speed for trucks without trailer have in general increased for all road types except two lane highways for which the speed has decreased; average free flow speed for trucks with trailers have in general decreased; and the average speed on two lane highways have in general decreased

  • 9.
    Olstam, Johan
    et al.
    Swedish National Road and Transport Research Institute, Society, environment and transport, Traffic analysis and logistics.
    Bernhardsson, Viktor
    Swedish National Road and Transport Research Institute, Society, environment and transport, Traffic analysis and logistics.
    van Noort, Martijn
    TNO.
    Wilmink, Isabel
    TNO.
    Klunder, Gerdien
    TNO.
    Choudhury, Charisma
    ITS Leeds.
    Tate, James
    ITS Leeds.
    Ligterink, Norbert
    TNO.
    Carsten, Oliver
    O.M.J.Carsten@its.leeds.ac.uk.
    Tapani, Andreas
    Swedish National Road and Transport Research Institute, Society, environment and transport, Traffic analysis and logistics.
    Traffic system impacts of green driving support systems2016Report (Other academic)
    Abstract [en]

    The global aim of the ecoDriver project was to deliver the most effective advice to drivers on fuel efficient driving by optimising the driver-powertrain-environment feedback loop. More specifically, the focus of the project was on the interaction between technology and the driver, since the behaviour of a driver is a critical element in energy efficiency. By increasing the acceptance of eco-driving applications through intelligent HMI and advice solutions, the ecoDriver project substantially contributes to the Europe 2020 goals through a much needed reduction of gas emissions and energy usage in transport, and thereby a significant reduction in the negative impact of transport on the environment.

    The ecoDriver advice to drivers covers the whole spectrum, from previewing the upcoming situation, over optimising the current driving situation, to post-drive feedback and learning. The aim of the project was to optimise human machine interfaces (HMIs) and advice to drivers for both portable devices within the vehicle which provide assistance to the driver (nomadic devices) and built-in systems, and to compare the effectiveness of each. This was addressed across a wide range of vehicles — e.g. cars, light trucks and vans, medium and heavy trucks and buses — covering both individual and collective transport. Lastly, the project did not only examine driving with current and near-term powertrains, but also with a full range of future vehicles, including hybrid and plug-in electric vehicles.

  • 10.
    Taylor, Nicholas B
    et al.
    Transport Research Laboratory (TRL).
    Nitsche, Philippe
    Austrian Institute of Technology (AIT).
    van Rooij, Lex
    TNO.
    Bernhardsson, Viktor
    Swedish National Road and Transport Research Institute, Society, environment and transport, Traffic analysis and logistics.
    Mocanu, Isabela
    Austrian Institute of Technology (AIT).
    Olstam, Johan
    Swedish National Road and Transport Research Institute, Society, environment and transport, Traffic analysis and logistics.
    Report on best practice, needs and derived incident scenarios2015Report (Other academic)
  • 11.
    Taylor, Nicholas B.
    et al.
    Transport Research Laboratory (TRL.
    Olstam, Johan
    Swedish National Road and Transport Research Institute, Society, environment and transport, Traffic analysis and logistics. Linköpings Universitet.
    Bernhardsson, Viktor
    Swedish National Road and Transport Research Institute, Society, environment and transport, Traffic analysis and logistics.
    Nitsche, Philippe
    AIT Austrian Institute of Technology.
    Modelling delay saving through pro-active incident management techniques2017In: European Transport Research Review, ISSN 1867-0717, E-ISSN 1866-8887, Vol. 9, no 4, article id 48Article in journal (Refereed)
    Abstract [en]

    Purpose: Road traffic incidents cause delay, affect public safety and the environment. The CEDR PRIMA project aims to extend practical guidance for traffic managers in pro-active Traffic Incident Management (TIM) techniques to reduce the impacts and associated costs of incidents.

    Methods: The paper describes modelling methods used in the project for assessing the effect of different management techniques on incident duration and travel delay under various scenarios, including collision, adverse weather, heavy vehicle breakdown and other obstruction, assuming various management strategies and generic impacts of novel technologies. Macroscopic simulations of 178 variations of 13 basic scenarios have been performed using a flexible and computationally efficient macroscopic queue model, results being verified by simulation using a velocity-based Cell Transmission Model (CTM-v).

    Results: The results of the two modelling methods are broadly consistent. While delays estimated by the two methods can differ by up to 20%, this is small compared to the factor of 30 range of modelled delays caused by incidents, depending on their nature and circumstances, and is not sufficient to affect general conclusions. Under the peak traffic conditions assumed, the most important factor affecting delay is whether running lanes can be kept open, but quick clearance of carriageway is not always feasible.

    Conclusions: Comparison of two very different modelling methods confirms their consistency within the context of highly scenario-dependent results, giving confidence in the results. Future research and data needs include further validation of the models, potential application to traffic flow and conflict prediction and incident prevention, and more complete and consistent recording of incident timelines and impacts.

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