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  • 1.
    Abate, Megersa
    et al.
    World Bank.
    Vierth, Inge
    Swedish National Road and Transport Research Institute, Society, environment and transport, Transport economics.
    Karlsson, Rune
    Swedish National Road and Transport Research Institute, Society, environment and transport, Traffic analysis and logistics.
    de Jong, Gerard
    University of Leeds.
    Baak, Jaap
    dSignificance.
    A disaggregate stochastic freight transport model for Sweden2018In: Transportation, ISSN 0049-4488, E-ISSN 1572-9435, p. 1-26Article in journal (Refereed)
    Abstract [en]

    This paper presents estimation results for models of transport chain and shipment size choice, as well as an implementation of the estimated disaggregate models (for two commodity groups), in the context of the national freight transport model for Sweden. The new model is a disaggregate and stochastic (logit) model, whereas the existing Swedish national model is deterministic. One advantage of the new approach is that it bases the underlying behavior of shippers on a stronger empirical foundation (that is micro-data from the Swedish Commodity Flow Survey, CFS). Another advantage is that it overcomes a well-known disadvantage of deterministic models that lead to implausibly large responses to changes in scenario or policy variables. Although estimation and implementation of aggregate stochastic models were done before, in the context of a national freight transport forecasting model, we think this is the first implementation of disaggregate freight transport chain and shipment size models estimated on choice data for individual shipments, certainly in Europe. We carried out a number of model runs with both versions of the implemented model to compare elasticities and found that transport cost and time elasticities for tonne-km are smaller (in absolute values) in the disaggregate stochastic model than in their deterministic counterparts.

  • 2.
    Abenoza, Roberto F.
    et al.
    KTH.
    Liu, Chengxi
    Swedish National Road and Transport Research Institute, Society, environment and transport, Traffic analysis and logistics.
    Cats, Oded
    KTH.
    Susilo, Yusak O.
    KTH.
    What is the role of weather, built-environment and accessibility geographical characteristics in influencing travelers’ experience?2019In: Transportation Research Part A: Policy and Practice, ISSN 0965-8564, E-ISSN 1879-2375, Vol. 122, p. 34-50Article in journal (Refereed)
    Abstract [en]

    We examine the effect of weather, accessibility and built-environment characteristics on overall travel experience as well as the experience with the latest trips. These are factors that are often disregarded in the travel satisfaction literature even though they are believed to largely influence the first mile of the door-to-door trip. This study fills a research gap in investigating all these factors by using, amongst other, a relatively large travel satisfaction survey from years 2009 to 2015 and by focusing on urban and peri-urban geographical contexts, the city and county of Stockholm (Sweden), respectively. The ordered logit model results show that county dwellers living close to a metro station and in well linked-to-all areas report higher overall travel satisfaction evaluations. In addition, precipitation and ground covered with snow have a negative influence on travel satisfaction. Our findings indicate that built-environment characteristics exert a rather weak influence on the travel experience, especially in the peri-urban context. However, some aspects such as living in areas with medium densities, low income and with high safety perceptions around public transport stations are associated with higher satisfaction levels. In turn, areas with single land uses are found to have lower travel satisfactions. These results are important for public transport planners and designers in devising measures to prevent and mitigate the negative outcome of some weather conditions and to conceive better designed transit oriented developments.

  • 3.
    Ait Ali, Abderrahman
    et al.
    Swedish National Road and Transport Research Institute, Society, environment and transport, Transport economics.
    Lidén, Tomas
    Swedish National Road and Transport Research Institute, Society, environment and transport, Traffic analysis and logistics.
    Minimal utilization rate for railway maintenance windows: a cost-benefit approach2022In: European Journal of Transport and Infrastructure Research, ISSN 1567-7133, E-ISSN 1567-7141, Vol. 22, no 2, p. 108-131Article in journal (Refereed)
    Abstract [en]

    Methods for economic assessment are often used in the rail sector to evaluate large infrastructure investments such as new high-speed lines. With larger networks and ageing infrastructure, these methods can also be used for planning maintenance. In this paper, we focus on the newly introduced concept of maintenance windows in Sweden. These are pre-allocated slots in the train timetable dedicated to performing, among others, periodic/frequent maintenance activities. To justify the pre-allocation of such windows, this study presents a method to find minimal utilization rates depending on window designs and traffic situations. Using a cost-benefit approach, the windows are assessed using a total social cost including work costs, loss in traffic production and reliability gains in future traffic. Based on a case study from the Southern main line in Sweden, we study the minimal utilization rate in different test scenarios, i.e., night or day shifts, asset degradation functions and designs of maintenance windows. The results show that lower utilization rates (4-42%) can be accepted during low-volume traffic or for partial closures, while higher utilization rates (47-83%) are required for full closures during high-volume traffic. Whether the rates are measured as the share of used window time or the share of utilized windows is less important, especially when higher utilization is required. Sensitivity analyses of asset knowledge indicate that parameters such as asset degradation function and minimum asset quality (and to a lesser extent traffic volume, discount rate and failure likelihood) can have a substantial effect on the minimum required utilization rates.

  • 4.
    Ait Ali, Abderrahman
    et al.
    Swedish National Road and Transport Research Institute, Society, environment and transport, Transport economics.
    Lidén, Tomas
    Swedish National Road and Transport Research Institute, Society, environment and transport, Traffic analysis and logistics.
    Minimal utilization rates for railway maintenance windows: a cost-benefit approach2021Report (Other academic)
    Abstract [en]

    Methods for economic assessment, e.g., cost-benefit analysis, are often used in the rail sector to evaluate large infrastructure investments such as building new high-speed railway lines. With larger railway networks and aging infrastructure, these methods can also be used for maintenance planning decisions. In this paper, we focus on basic maintenance and the newly introduced concept of maintenance windows in Sweden. These are pre-allocated slots in the annual train timetable dedicated to performing, among others, periodic/frequent maintenance activities such as inspections, maintenance and repairs. To justify the pre-allocation of such windows, this study presents a method to find minimal utilization rates depending on window designs and traffic situations. Using a cost-benefit approach, the maintenance windows are assessed using a total social cost including maintenance work costs, loss in traffic production and reliability gains in future traffic. Based on a case study from the Southern main line in Sweden, we study the minimal utilization rate in different test scenarios, i.e., night or day shifts, asset degradation functions and designs of maintenance windows. The results show that lower utilization rates (5-50%) can be accepted during low-volume traffic or for partial closures, while higher utilization rates (50-90%) are required for full closures during high-volume traffic. Whether the rates are measured as share of used window time or share of utilized windows is less important, especially when higher utilization is required.

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  • 5.
    Aldenius, Malin
    et al.
    Lund University.
    Tsaxiri, Panagiota
    Swedish National Road and Transport Research Institute, Society, environment and transport, Traffic analysis and logistics. Linköping University.
    Lidestam, Helene
    Swedish National Road and Transport Research Institute, Society, environment and transport, Traffic analysis and logistics. K2.
    The role of environmental requirements in Swedish public procurement of bus transports2021In: International Journal of Sustainable Transportation, ISSN 1556-8318, E-ISSN 1556-8334, Vol. 16, no 5, p. 391-405Article in journal (Refereed)
    Abstract [en]

    The transport sector needs to become sustainable and public transport has an important role to play. Green public procurement has proven to have great potential to influence the transition to a sustainable public transport sector. Sweden is a good example of a country that uses public procurement in the public transport sector to a large extent and has at the same time come far in the transition to renewable fuel. The aim of this study is to examine what role public transport authorities (PTAs) can have in supporting more environmentally sustainable public transport through public procurement. This was done by a content analysis regarding the expressions of environmental requirements historically, over a ten-year period, in tender documents in Sweden, followed by a workshop where the implications of the findings and future tender processes were discussed with relevant actors. The results showed that all the environmental requirements have become stricter during the studied period, but indicate a tendency for higher use of environmental requirements in tendering of larger areas as well as in tendering of public transport within cities. Specifically, for requirements for fuel, the same tenders also use specific requirements to a higher extent. However, the subsequent workshop discussions indicated that the use of specific requirements is one reason for disagreement among involved actors. Overall, this study of the Swedish public transport case showed that PTAs have a large potential to support more environmentally sustainable solutions using environmental requirements in public procurement.

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  • 6.
    Allström, Andreas
    et al.
    Sweco.
    Kristoffersson, Ida
    Swedish National Road and Transport Research Institute, Society, environment and transport, Traffic analysis and logistics. Kungliga Tekniska Högskolan.
    Susilo, Yusak
    KTH.
    Smartphone based travel diary collection: Experiences from a field trial in Stockholm2017In: Transportation Research Procedia, Elsevier B.V. , 2017, Vol. 26, p. 32-38Conference paper (Refereed)
    Abstract [en]

    Currently, there is a great need for new methods to collect travel data. Traditional methods have considerable drawbacks and, at the same time, the models used to analyse the transport system require more and more detailed and high-quality data. Since most smartphones are equipped with various sensors that can be used to determine the location of the smartphone, and since smartphones are integrated in the daily life of most people, they provide an unprecedented opportunity for large-scale travel data collection. This method has a great potential to solve the problems related to the estimation of distance/travel time, geographic coding of departure/destination locations and forgotten trips and it will also provide a more detailed and extensive data set.

    In a recently completed research project the feasibility of replacing or complementing the traditional travel diary, with a suite of tools that make use of smartphone collected travel data has been evaluated. The advantages and disadvantages of the traditional method and the proposed method were studied. For a fair comparison, both methods have been tested in the same city, at the same time, and with the same respondents. To achieve the objectives of the project, MEILI, a system that consists of a smartphone application for capturing the movement of users and a web application for allowing the users to annotate their movement, has been deployed. In total 2142 trips were collected and annotated by 171 users. 51 of the users annotated trips covering more than a week. The main findings of the paper are that smartphone based data collection is feasible, that the algorithms to save battery work well and that trips of the same respondent vary considerably depending on day of the week.

  • 7.
    Allström, Andreas
    et al.
    Trivector .
    Olstam, Johan
    Swedish National Road and Transport Research Institute, Society, environment and transport, Traffic analysis and logistics. Linköpings universitet, Kommunikations- och transportsystem.
    Thorsson, Tobias
    WSP .
    Analys av modeller för beräkning av framkomlighet i korsningar2008Report (Other academic)
  • 8.
    Alméras, Caroline
    et al.
    ECTRI, Brussels.
    Buisson, Christine
    IFSTTAR, Lyon.
    Olstam, Johan
    Swedish National Road and Transport Research Institute, Society, environment and transport, Traffic analysis and logistics.
    Papamichail, Ioannis
    Technical University of Crete, Chania.
    Ponweiser, Wolfgang
    AIT Austrian Institute of Technology GmbH, Vienna,.
    Wagner, Peter
    German Aerospace Center, Institute for Transportation Systems, Berlin.
    Zero crashes, zero congestion, and zero emissions: future research in traffic management2020In: Proceedings of 8th Transport Research Arena TRA 2020, 2020, p. 6-Conference paper (Refereed)
    Abstract [en]

    This text is the result of the Thematic Group Traffic Management of the ECTRI – European Conference of Transport Research Institutes. As a position paper, it states the challenges that the European Research Agenda will have to face if the following goals for a future transportation system are considered: • User-aware mobility • Zero accidents and zero emissions • Minimum space, time, energy & costs for transport It describes in a concise manner the research approaches needed to achieve the realization of these goals.

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  • 9.
    Andersson, Angelica
    Swedish National Road and Transport Research Institute, Society, environment and transport, Traffic analysis and logistics. Linköpings universitet, Kommunikations- och transportsystem.
    Mode choice modelling of long-distance passenger transport based on mobile phone network data2022Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Reliable forecasting models are needed to achieve the climate related goals in the face of increasing transport demand. Such models can predict the long-term behavioural response to policy interventions, including infrastructure investments, and thus provide valuable pre-dictions for decision makers. Contemporary forecasting models are mainly based on national travel surveys. Unfortunately, the response rates of such surveys have steadily declined, implying that the respondents become less representative of the whole population. A particular weakness is that it is likely that respondents with a high valuation of time are less willing to respond to surveys (because they have less time available for such), and therefore there is a high chance that they are underrepresented among the respondents. The valuation of time plays an important role for the cost benefit analyses of public policies including transport investments, and there is no reliable way of controlling for this uneven sampling of time preferences. Fortunately, there is simultaneously an increase in the number of signals sent between mobile phones and network antennae, and research has now reached the point where it is possible to determine not only the travel destination but also the travel mode based on mobile phone network antennae connections. The aim of this thesis is to investigate if and how mobile phone network data can be used to estimate transportation mode choice demand models that can be used for forecasting and planning. Key challenges with using this data source in the context of mode choice models are identified and met. The identified challenges include uncertainty in the choice variable, the difficulty to distinguish car and bus trips, and the lack of information about the trip purpose. In the first paper we propose three possible model formulations and analyse how the uncertainty in the choice outcome variable would play a role in the different model formulations. We also conclude that it is indeed possible to estimate mode choice demand models based on mobile phone network data, with good results in terms of behavioural interpretability and significance. In the second paper we estimate models using a nested logit structure to account for the difficulty in separating bus and car, and a latent class model specification to meet the challenge of having an unknown trip purpose. 

    List of papers
    1. Long-distance mode choice model estimation using mobile phone network data
    Open this publication in new window or tab >>Long-distance mode choice model estimation using mobile phone network data
    Show others...
    2022 (English)In: Journal of Choice Modelling, ISSN 1755-5345, E-ISSN 1755-5345, Vol. 42, article id 100337Article in journal (Refereed) Published
    Abstract [en]

    In this paper we develop two methods for the use of mobile phone data to support the estimation of long-distance mode choice models. Both methods are based on logit formulations in which we define likelihood functions and use maximum likelihood estimation. Mobile phone data consists of information about a sequence of antennae that have detected each phone, so the mode choice is not actually observed. In the first trip-based method, the mode of each trip is inferred by a separate procedure, and the estimation process is then straightforward. However, since it is not always possible to determine the mode choice with certainty (although it is possible in the majority of cases), this method might give biased results. In our second antenna-based method we therefore base the likelihood function on the sequences of antennae that have detected the phones. The estimation aims at finding a parameter vector in the mode choice model that would explain the observed sequences best. The main challenge with the antenna-based method is the need for detailed resolution of the available data. In this paper we show the derivation of the two methods, that they coincide in case of certainty about the chosen mode and discuss the validity of assumptions and their advantages and disadvantages. Furthermore, we apply the first trip-based method to empirical data and compare the results of two different ways of implementing it. © 2021 The Authors

    Place, publisher, year, edition, pages
    Elsevier Ltd, 2022
    National Category
    Transport Systems and Logistics
    Identifiers
    urn:nbn:se:vti:diva-17561 (URN)10.1016/j.jocm.2021.100337 (DOI)2-s2.0-85120617832 (Scopus ID)
    Available from: 2022-03-24 Created: 2022-03-24 Last updated: 2022-10-11Bibliographically approved
    2. Mode Choice Latent Class Estimation on Mobile Network Data
    Open this publication in new window or tab >>Mode Choice Latent Class Estimation on Mobile Network Data
    Show others...
    (English)Manuscript (preprint) (Other academic)
    Abstract [en]

    In this paper we use a nested latent class logit specification to define and estimate a large-scale mode choice demand forecasting model. We estimate this model based on mobile phone network data translated to roughly 100 000 long-distance trips within Sweden, achieving convergence of the model and credible parameter estimates. We develop methods to address two problems stemming from the nature of this data: the difficulties of distinguishing bus trips from car trips (since they share the same infrastructure) and distinguishing business from private trips (since trip purpose is unknown). To address the first issue, we estimate a nested logit model with an artificial nest that accounts for the differences in utility between bus and car. To address the latter issue, we estimate a latent class model, identifying classes of trips interpreted as private and business trips. Addressing these two issues substantially improves model fit. 

    National Category
    Transport Systems and Logistics
    Identifiers
    urn:nbn:se:vti:diva-19097 (URN)10.2139/ssrn.4246865 (DOI)
    Available from: 2022-10-28 Created: 2022-10-28 Last updated: 2022-10-28Bibliographically approved
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  • 10.
    Andersson, Angelica
    et al.
    Swedish National Road and Transport Research Institute, Society, environment and transport, Traffic analysis and logistics.
    Börjesson, Maria
    Swedish National Road and Transport Research Institute, Society, environment and transport, Transport economics.
    Breyer, Nils
    Linköpings universitet.
    Daly, Andrew
    University of Leeds.
    Engelson, Leonid
    Linköpings universitet.
    Kristoffersson, Ida
    Swedish National Road and Transport Research Institute, Society, environment and transport, Traffic analysis and logistics.
    Mode Choice Latent Class Estimation on Mobile Network DataManuscript (preprint) (Other academic)
    Abstract [en]

    In this paper we use a nested latent class logit specification to define and estimate a large-scale mode choice demand forecasting model. We estimate this model based on mobile phone network data translated to roughly 100 000 long-distance trips within Sweden, achieving convergence of the model and credible parameter estimates. We develop methods to address two problems stemming from the nature of this data: the difficulties of distinguishing bus trips from car trips (since they share the same infrastructure) and distinguishing business from private trips (since trip purpose is unknown). To address the first issue, we estimate a nested logit model with an artificial nest that accounts for the differences in utility between bus and car. To address the latter issue, we estimate a latent class model, identifying classes of trips interpreted as private and business trips. Addressing these two issues substantially improves model fit. 

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    fulltext
  • 11.
    Andersson, Angelica
    et al.
    Swedish National Road and Transport Research Institute, Society, environment and transport, Traffic analysis and logistics. Linköping University, Sweden.
    Engelson, Leonid
    Linköping University, Sweden.
    Börjesson, Maria
    Swedish National Road and Transport Research Institute, Society, environment and transport, Transport economics. Linköping University, Sweden.
    Daly, Andrew
    University of Leeds, United Kingdom.
    Kristoffersson, Ida
    Swedish National Road and Transport Research Institute, Society, environment and transport, Traffic analysis and logistics.
    Long-distance mode choice model estimation using mobile phone network data2022In: Journal of Choice Modelling, ISSN 1755-5345, E-ISSN 1755-5345, Vol. 42, article id 100337Article in journal (Refereed)
    Abstract [en]

    In this paper we develop two methods for the use of mobile phone data to support the estimation of long-distance mode choice models. Both methods are based on logit formulations in which we define likelihood functions and use maximum likelihood estimation. Mobile phone data consists of information about a sequence of antennae that have detected each phone, so the mode choice is not actually observed. In the first trip-based method, the mode of each trip is inferred by a separate procedure, and the estimation process is then straightforward. However, since it is not always possible to determine the mode choice with certainty (although it is possible in the majority of cases), this method might give biased results. In our second antenna-based method we therefore base the likelihood function on the sequences of antennae that have detected the phones. The estimation aims at finding a parameter vector in the mode choice model that would explain the observed sequences best. The main challenge with the antenna-based method is the need for detailed resolution of the available data. In this paper we show the derivation of the two methods, that they coincide in case of certainty about the chosen mode and discuss the validity of assumptions and their advantages and disadvantages. Furthermore, we apply the first trip-based method to empirical data and compare the results of two different ways of implementing it. © 2021 The Authors

  • 12.
    Andersson-Sköld, Yvonne
    et al.
    Swedish National Road and Transport Research Institute, Society, environment and transport, Environment.
    Afridi, Muhammad Amjad
    Skelleftea Municipal, Sweden; KTH, Sweden.
    Nordin, Lina
    Swedish National Road and Transport Research Institute, Infrastructure, Infrastructure maintenance.
    Patrício, João
    Swedish National Road and Transport Research Institute, Society, environment and transport, Environment.
    Lindgren, Åsa
    Swedish Transport Administration, Sweden.
    Johansson, Carl-Martin
    Swedish Transport Administration, Sweden.
    Olofsson, Alexandra
    Swedish Transport Administration, Sweden..
    Andersson, Angelica
    Swedish National Road and Transport Research Institute, Society, environment and transport, Traffic analysis and logistics. Linköping University, Sweden.
    Erlingsson, Sigurdur
    Swedish National Road and Transport Research Institute, Infrastructure, Pavement Technology. KTH, Sweden;University of Iceland, Iceland.
    Development of the SUNRA Tool to Improve Regional and Local Sustainability of the Transportation Sector2022In: Sustainability, E-ISSN 2071-1050, Vol. 14, no 18, article id 11275Article in journal (Refereed)
    Abstract [en]

    To fulfil the global sustainable development goals (SDGs), achieving sustainable development is becoming urgent, not least in the transportation sector. In response to this, the sustainability framework Sustainability National Road Administrations (SUNRA) was developed to contribute to improving the sustainability performance of national road administrations across Europe. In the present study, the framework has been tested, applied and further developed to be applicable for target setting and follow-up at the project level at both the Swedish Transport Administration (STA) and at municipal levels. The aim was a framework relevant for investment, re-investments, maintenance and operation projects and also to make it more user applicable. The study also investigated how the framework can contribute to sustainability, identified drivers and barriers for applying the framework and examined whether the framework can be applied and adapted to projects of different complexities. The adaptations and developments were done in collaboration between researchers and practitioners. The results show that the framework could easily be used and adapted for investment, re-investment, maintenance and operation projects in the planning stage, as well as for small municipal establishments, construction or reconstruction of residential areas and frequent maintenance. The framework contributes to increased awareness on sustainability, and it provides a common structure and transparency on how infrastructure project goals/targets are set and fulfilled. The framework can also be applied to follow the fulfilment of the goals/targets and thereby adapt the project to better fulfil the goals. Identified barriers include the lack of obligations and lack of experience in using sustainability frameworks.

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  • 13. Anna, Pernestål
    et al.
    Albin, Engholm
    Kristoffersson, Ida
    Swedish National Road and Transport Research Institute, Society, environment and transport, Traffic analysis and logistics.
    Jussila Hammes, Johanna
    Swedish National Road and Transport Research Institute, Society, environment and transport, Transport economics.
    The Impacts of Automated Vehicles on the Transport System and How to Create Policies that Target Sustainable Development Goals2020In: Shaping Smart Mobility Futures: Governance and Policy Instruments in times of Sustainability Transitions / [ed] Paulsson, Alexander; Sørensen, Claus Hedegaard, Emerald Publishing Limited , 2020, p. 37-53Chapter in book (Other academic)
    Abstract [en]

    Abstract Automated vehicles are likely to have significant impacts on the transport system such as increased road capacity, more productive/enjoyable time spent travelling in a car, and increased vehicle kilometres travelled. However, there is a great risk that automated driving may negatively impact the environment if adequate policies are not put in place. This chapter examines the effects of driverless vehicles and the types of policies required to attain sustainable implementation of the technology. To understand the effects on a systemic level, and to understand the needs and impacts of policies, the dynamics must be understood. Therefore, a causal loop diagram (CLD) is developed and analysed. One important insight is that the effects of driverless vehicles are mainly on the vehicular level (e.g., the reduced number of accidents per vehicle). These effects can be cancelled out on a systemic level (e.g., due to increased vehicle-kilometre travelled (VKT) that increases total number of accidents). The marginal costs of road transport are central to both freight and passenger transport. Automation will reduce marginal costs and shift the equilibrium in the transport system towards a state with higher VKT. This will lead to greater energy consumption and higher emissions. To attain sustainability goals, there might be a need to balance this reduction of marginal costs by using policy instruments. In the work, CLDs is experienced to be a useful tool to support the collaboration between experts from different fields in the dialogue about policies.

  • 14.
    Anund, Anna
    et al.
    Swedish National Road and Transport Research Institute, Traffic and road users, The Human in the Transport system..
    Berglund, Magnus
    Swedish National Road and Transport Research Institute, Society, environment and transport, Traffic analysis and logistics.
    Bröms, Per
    RISE.
    Synnedsattas resor med buss: framtiden med autonoma bussar2021Report (Other academic)
    Abstract [sv]

    Att ha tillgång till transportsystemet är extra viktig, men även utmanande för personer med synnedsättningar. Resande med synnedsättningar är vanligtvis mer beroende av sin hörsel och av god förutsägbarhet under resans samtliga moment. I en framtid kan detta förväntas bli en ännu större utmaning med fler autonoma och elektrifierade fordon i transportsystemet.

    Syftet med föreliggande studie var att fånga synnedsattas behov och önskningar kring stöd för att tillgängliggöra resande med framtidens autonoma bussar. Fokus har varit på digitala lösningar och där två systerprojekt har använts som ingång. Det ena projektet handlar om Augmented Reality (förstärkt verklighet - AR) baserade lösningar i kollektivtrafiken, det andra är mobilitetsplattformen i Linköping kallad Ridethefuture, i vilken 2 mindre autonoma elektrifierade bussar har använts för medåkande med syftet att fånga synnedsattas reflektioner.

    Studien omfattar en inledande kunskapsgenomgång där såväl en benchmarking som en litteraturgenomgång gjorts. Vidare har en inledande fokusgrupp med fokus på synnedsattas resande generellt och deras förväntningar på framtidens autonoma system genomförts och därefter medåkandeobservationer med synnedsatta. En kompletterade uppgiftsanalys genomfördes i syfte att öka kunskapen om vilka behov resande har i allmänhet.

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  • 15.
    Anund, Anna
    et al.
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Kecklund, Göran
    Stockholm university, Stress research institute.
    Kircher, Albert
    Swedish National Road and Transport Research Institute, Traffic and road users, Vehicle technology and simulation.
    Tapani, Andreas
    Swedish National Road and Transport Research Institute, Society, environment and transport, Traffic analysis and logistics.
    Åkerstedt, Torbjörn
    Karolinska institutet, Clinical neuroscience.
    The effects of driving situation on sleepiness indicators after sleep loss: A driving simulator study2009In: Industrial Health, ISSN 0019-8366, E-ISSN 1880-8026, Vol. 47, no 4, p. 393-401Article in journal (Refereed)
    Abstract [en]

    Almost all studies of sleepy driving are carried out in driving simulators and with monotonous road conditions (no interaction with other cars). The present study investigated indicators of sleepy driving in a more challenging scenario after a night awake. 17 participants drove a high fidelity moving base driving simulator experiment while sleepiness was monitored physiologically and behaviourally. Short periods of situations of free driving (no other vehicles) alternated with short periods of following another vehicle (car following) with and without the possibility to overtake. The result showed that a night of prior sleep loss increased sleepiness levels at the wheel (eye closure duration and lateral variability) compared to after a night of normal sleep. Blink duration while overtaking was significantly lower compared to the other situations, it was at the same level as after night sleep. Speed when passing a stopped school bus was not significantly affected by sleepiness. However the warning caused a more rapid reduction of speed. In conclusion, a moderately challenging driving contest did not affect sleepiness indicators, but a very challenging one did so (overtaking). This suggests that it is important to monitor the driving situation in field operational tests of sleepy driving.

  • 16.
    Anund, Anna
    et al.
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Tapani, Andreas
    Swedish National Road and Transport Research Institute, Society, environment and transport, Traffic analysis and logistics. Linköpings universitet, Kommunikations- och transportsystem.
    Chalkia, Eleni
    Centre of Research and Technology Hellas/Hellenic Institute of Transport, Thessaloniki, Greece .
    Watch Out! Something Precious is Moving2011In: Infrastructure and Safety in a Collaborative World: Road Traffic Safety / [ed] E. Bekiaris, M. Wiethoff och E. Gaitanidou, Berlin Heidelberg: Springer Berlin/Heidelberg , 2011, 1, p. 233-242Chapter in book (Other academic)
    Abstract [en]

    One critical situation when a driver needs to have a high degree of awareness, to avoid critical situations or crashes, is when passing a school bus, stopped for boarding or de-boarding of children. With the help of an experiment in VTI’s moving base driving simulator, a scenario, using in-vehicle information before the bus was reached, was tested. The aim was to enhance drivers’ perception, in order to reduce the speed of vehicles passing by the stopped bus. Both alert and sleep deprived drivers were tested.

    The results showed a significant speed reduction thanks to the information given beforehand. Sleep deprivation did not seem to have an impact on speed reduction. This suggests that the warning signals are seen and followed, regardless the drivers’ state of alertness. Thus, it seems likely that this type of information may be useful as an Intelligent Transport System (ITS), to provide driver support about upcoming hazards. One step towards further research in this direction is performed within the EU project SAFEWAY2SCHOOL, the main objectives of which are presented at the end of this chapter.

  • 17.
    Aria, Erfan
    et al.
    Linköpings universitet.
    Olstam, Johan
    Swedish National Road and Transport Research Institute, Society, environment and transport, Traffic analysis and logistics.
    Schwietering, Christoph
    Schwietering Traffic Engineers, DE.
    Investigation of Automated Vehicle Effects on Driver's Behavior and Traffic Performance2016In: Transportation Research Procedia, E-ISSN 2352-1465, Vol. 15, p. 761-770Article in journal (Refereed)
    Abstract [en]

    Advanced Driver Assistance Systems (ADAS) offer the possibility of helping drivers to fulfill their driving tasks. Despite different encouraging factors, automated driving raise some concerns such as possible loss of situation awareness, overreliance on automation and system failure. This paper aims to investigate the effects of AV on driver’s behavior and traffic performance. A literature review was conducted to examine the AV effects on driver’s behavior. Findings from the literature survey reveal that conventional vehicles (CV), i.e. human driven, which are driving close to a platoon of AV with short THW, tend to reduce their THW and spend more time under their critical THW. Additionally, driving highly AV reduce situation awareness and can intensify driver drowsiness, exclusively in light traffic.

    In order to investigate the influences of AV on traffic performance, a simulation case study consisting of a 100% AV scenario and a 100% CV scenario was performed using microscopic traffic simulation. Outputs of this simulation study reveal that the positive effects of AV on roads are especially highlighted when the network is crowded (e.g. peak hours). This can definitely count as a constructive point for the future of road networks with higher demands. In details, average density of autobahn segment remarkably improved by 8.09% during p.m. peak hours in the AV scenario, while the average travel speed enhanced relatively by 8.48%. As a consequent, the average travel time improved by 9.00% in the AV scenario.

    The outcome of this study jointly with the previous driving simulator studies illustrates a successful practice of microscopic traffic simulation to investigate the effects of AV. However, further development of the microscopic traffic simulation models are required and further investigations of mixed traffic situation with AV and CV need to be conducted.

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  • 18.
    Arvidsson, Niklas
    Swedish National Road and Transport Research Institute, Society, environment and transport, Traffic analysis and logistics. VTI.
    En förstudie av godscykeln och dess användningsområde: en historisk hybrid och framtida möjlighet för ett hållbart distributionssystem i våra städer2020Report (Other academic)
    Abstract [en]

    The last part of the freight chain is usually the most inefficient, costly and most emission-intensive part of the chain. Fill rates are low, the cost of the last kilometer can in some cases amount to up to one-third of the total cost and the negative effects of transport, emissions and accidents, become extra noticeable in environments where people live. The use of smaller vehicles that are better suited to the assignment is something we intend to investigate further in this report. A simpler analysis of life cycle data for freight bicycles shows that they are many times more environmentally friendly than vans. There are also several companies in Sweden that deliver packages with freight bicycles and that do this with profit. Many of the major transport and logistics companies have already started using these types of vehicles. The fact that freight bikes can usually maintain the same average speed as vans during the day makes the business model interesting. The reason for this is that cargo bikes can get closer to the customer, do not need to circulate to find parking, can take shortcuts and use both the bicycle network and the road network. So, in some circumstances, a van can be replaced with a freight bicycle.

    It is also interesting to study the standardization process that has begun regarding the choice of load carrier. In recent years, we have seen a development in which attempts are made to make the transfer between different vehicles as smooth as possible, for example with a standard removable and stackable mini-container. This could significantly improve the handling, as you can go from handling load carriers rather than many small packages.

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  • 19.
    Benz, Thomas
    et al.
    PTV AG, Germany.
    Gaitanidou, Evangelia
    Hellenic Institute of Transport, Greece.
    Spyropoulou, Ioanna
    National Technical University of Athens, Greece.
    Yannis, George
    National Technical University of Athens, Greece.
    Tapani, Andreas
    Swedish National Road and Transport Research Institute, Society, environment and transport, Traffic analysis and logistics.
    Modelling road traffic safety: the IN-SAFETY approach2006In: Proceedings of the 13th World Congress and Exhibition on Intelligent Transport Systems and Services, 2006Conference paper (Other academic)
    Abstract [en]

    This paper presents a model-based approach to road traffic safety developed within the EU funded project IN-SAFETY. Several existing models, both micro- and macro-models, will be adapted and used to assess safety related effects of ITS measures. Examples of such measures include but are not limited to ADAS and IVIS. While the micro-models will determine the individual vehicles' safety related behaviour, the macro-models will find out about the network wide aspects. Various models will be extended to cope with the ITS measures envisaged and then applied to relevant safety critical conditions. Major input will be available from the different test sites of the project, which are spread to cover the most significant aspects within the EU road environment.

  • 20.
    Benz, Thomas
    et al.
    PTV AG, Karlsruhe.
    Gaitanidou, Evangelia
    Centre for Research and Technology Hellas, Hellenic Institute of Transport (CERTH/HIT).
    Tapani, Andreas
    Swedish National Road and Transport Research Institute, Society, environment and transport, Traffic analysis and logistics.
    Toffolo, Silvana
    IVECO, ER&C, Torino, Italy .
    Yannis, George
    National Technical University of Athens (NTUA), Athens, Greece.
    Spyropoulou, Ioanna
    National Technical University of Athens (NTUA), Athens, Greece.
    Models on the Road2011In: Infrastructure and Safety in a Collaborative World / [ed] E. Bekiaris, M. Wiethoff och E. Gaitanidou, Berlin Heidelberg: Springer Berlin/Heidelberg, 2011, 1, p. 97-124Chapter in book (Other academic)
    Abstract [en]

    In this chapter, the application of macro and micro traffic simulation modelling for the needs of road safety assessment and planning is dealt. The overall concept of traffic simulation modelling regarding safety is presented, together with a series of macro and micro simulation models (namely RuTSim, S-Paramics, SATURN and VISSIM) that are widely used and have been specifically applied for the needs of IN-SAFETY project. ITS and ADAS related scenarios defined within IN-SAFETY, aiming to enhance the road safety level, have been tested through specially developed applications of these models and their results indicate the influence of the use of such technologies, as well as the effectiveness of the selected models in simulating and evaluating their effects. Future enhancement in the models will provide the possibility of further using them in the context of road safety and the involvement of innovative technologies.

  • 21.
    Bergh, Torsten
    et al.
    Movea.
    Nordqvist, Karin
    Trafikverket.
    Strömgren, Per
    Movea.
    Davidsson, Fredrik
    Movea.
    Bång, Karl Lennart
    KTH.
    Carlsson, Arne
    Swedish National Road and Transport Research Institute, Society, environment and transport, Traffic analysis and logistics.
    Capacity Issues in Sweden - Applications and Research2016In: Transportation Research Procedia, 2016, Vol. 15, p. 36-50Conference paper (Refereed)
    Abstract [en]

    This paper gives an overview of the Swedish trunk road system and present objectives, guidelines concerning capacity and level of service procedures to assess these issues in the feasibility and design procedure are also described.

    An important goal in Sweden is investments and speed limit changes over a 10 year time scale to decrease the C02-exposure. The long term speed limit overview with the objective to require median barriers at speed limits over 80 kph with results so far is presented. By now over 50 % of the former traffic load over 80 kph is decreased to 80 kph. Some 2,700 km have been retrofitted to 2+1 median barrier roads with speed limit mainly 100 kph.

    An overview is also given of the updated Swedish Highway Capacity Manual with new chapters especially on jam densities, entry lanes, weaving areas and traffic signals. Some interesting research projects are also briefly covered. These are 2+1 median barrier roads, capacities at motorway work zones, speed harmonisation with variable speed limits on motorways to increase capacity, ramp metering and Drive Me (autonomous driving full scale tests).

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  • 22.
    Bergh, Torsten
    et al.
    Movea.
    Remgård, Mats
    Trafikverket.
    Carlsson, Arne
    Olstam, Johan
    Swedish National Road and Transport Research Institute, Society, environment and transport, Traffic analysis and logistics.
    Strömgren, Per
    Movea.
    2+1-roads Recent Swedish Capacity and Level-of-Service Experience2016In: Transportation Research Procedia, E-ISSN 2352-1465, Vol. 15, p. 331-345Article in journal (Refereed)
    Abstract [en]

    The first Swedish 2+1 median barrier road was opened in 1998. The concept was to retrofit the standard existing two-lane 13 m paved width cross-section at 90 and 110 kph posted speed limit without widening. This design has one continuous lane in each direction, a middle lane changing direction every one to three kilometres with a median barrier separating the two traffic directions. Today over 2 700 km 2+1 median barrier roads are opened for traffic. AADT’s vary from some 3 000 to 20 000 with an average just below 10 000 nowadays normally with 100 kph.

    The concept has lately been enhanced also to cover the existing 9 m paved width cross-section. The design concept is the same from a driver’s viewpoint, one continuous lane in each direction with a middle lane changing direction and a separating median barrier. This is created by introducing a continuous median barrier and adding overtaking lanes within an overtaking strategy. The differences are the existence of 1+1-sections, less overtaking opportunities and a slightly more narrow cross-section. Some 15 projects are opened. The purpose of this paper is to summarize present knowledge on level-of-service issues as they are presented in Swedish design and assessment guidelines and to give an overview of field measurements and theoretical analytical and simulation studies supporting the recommendations.

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  • 23.
    Berglund, Magnus
    Swedish National Road and Transport Research Institute, Society, environment and transport, Traffic analysis and logistics. VTI.
    Strategic positioning of the emerging third-party logistics providers2000Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The dissertation deals with the so-called Third-Party logistics Provider (TPLP) with the purpose of explaining strategic positions of the emerging TPLPs. The development of Third-Party Logistics (TPL) can be said to have occurred during the last 15 - 20 years and have created a new kind of service, i.e. the management and execution of logistics process. These services have created a new market and consequently a new type of service provider is emerging. These service providers predominantly originate from traditional offerings in the logistics area, e.g. transportation and warehousing activities. However, previous works on TPL have neglected the provider's situation especially by not explicitly recognizing the shifts from single activity services to comprehensive and coordinated multiple activity offerings and from a functional support orientation to a process approach.

    Strategic positioning is an established perspective on strategy, but the use varies considerably. In this dissertation strategic positioning is connected to how TPLPs create value for their clients which links positioning to skills or capabilities. Furthermore, the position is regarded as a result of the fit between activities, resources and strategic positioning. This theoretical frame of reference, based on strategic positioning and value creation for service organizations, is new in the literature on TPL. The general methodological approach of the study is alternation between empirical findings and theoretical analyses in a stepwise pattern. Since the organizations studied had not been theoretically analyzed before, empirical observations were instrumental in describing the novel phenomena. The empirical foundation of the dissertation is two studies executed during 1996-7 and 1998-9. The first study contains 21 Australian, European, and North-American TPLPs. The second study is based on 53 European TPL buyers. Both studies used a combination of questionnaires and interviews for collecting data of both quantitative and qualitative character. The empirical analysis is best described as a qualitative approach supported by statistical techniques whenever possible.

    The dissertation presents a comprehensive empirical description of the current status and anticipated change of both the TPLPs and their customers. The main contribution of this dissertation is however: tools for describing TPLPs, a model of the value system that connects providers and buyers of TPL, and a position model for TPLPs.

    List of papers
    1. Third-Party Logistics in Europe: five years later
    Open this publication in new window or tab >>Third-Party Logistics in Europe: five years later
    2000 (English)In: International Journal of Physical Distribution & Logistics Management, ISSN 0960-0035, E-ISSN 1758-664X, Vol. 30, no 5, p. 425-442Article in journal (Refereed) Published
    National Category
    Social Sciences
    Identifiers
    urn:nbn:se:vti:diva-15329 (URN)19899 (Local ID)19899 (Archive number)19899 (OAI)
    Available from: 2020-06-24 Created: 2020-06-24 Last updated: 2020-09-08Bibliographically approved
    2. Third Party Logistics: Is there a Future?
    Open this publication in new window or tab >>Third Party Logistics: Is there a Future?
    1999 (English)In: The International Journal of Logistics Management, ISSN 0957-4093, Vol. 10, no 1Article in journal (Refereed) Published
    Place, publisher, year, edition, pages
    Emerald Group Publishing Limited, 1999
    National Category
    Transport Systems and Logistics
    Identifiers
    urn:nbn:se:vti:diva-15326 (URN)10.1108/09574099910805932 (DOI)19892 (Local ID)19892 (Archive number)19892 (OAI)
    Available from: 2020-06-24 Created: 2020-06-24 Last updated: 2023-02-03Bibliographically approved
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  • 24.
    Berglund, Magnus
    Swedish National Road and Transport Research Institute, Society, environment and transport, Traffic analysis and logistics. Linköpings universitet, Logistik.
    Third-party logistics providers: towards a conceptual strategic model1997Licentiate thesis, monograph (Other academic)
    Abstract [en]

    The purpose of the study is to: 1. develop a model for studying the strategies of third-party providers, and 2. preparing empirically supported hypotheses regarding the TPL providers strategies. Empirical data has been gathered from 21 Australian, European, and North- American targeted TPL providers, all recognized as large, innovative or influential industry representatives.

    The thesis propose an empirically supported model for studying positions or for positioning of TPL providers, based on both served markets and internal industry variables. Further, the TPL providers expected development, the values delivered to clients, and activity and capability for supply chain integration are explored.

    The results of the study indicate that the TPL providers in general have similar strategies, and expect to develop in similar ways. The main values provided to clients are Cost and the possibility to Focus on Core, and the main mechanisms for creating that value are Operative Competence and Systems Development.

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  • 25.
    Berglund, Svante
    et al.
    WSP.
    Kristoffersson, Ida
    Swedish National Road and Transport Research Institute, Society, environment and transport, Traffic analysis and logistics.
    Anslutningsresor: en deskriptiv analys2020Report (Other academic)
    Abstract [sv]

    Den här rapporten är en del i ett forskningsprojekt där vi studerar det svenska anslutningsresandet. Här beskrivs anslutningsresor med data från svenska nationella resvaneundersökningen. Ungefär 35 procent av alla långväga (mer än 10 mil) resor sker med ett färdmedel som förutsätter en resa till en station eller flygplats. De flesta långväga resor har en mycket enkel struktur med korta anslutningsresor till huvudfärdmedlet. Det är ovanligt med fler färdmedel under en resa förutom huvudfärdmedel, anslutande och avslutande färdmedel. Anslutningsfärdmedel och huvudfärdmedel är enkelt identifierbara i data. Det råder också en stor symmetri mellan utresa och återresa avseende både huvudfärdmedel och färdmedel för anslutningsresa. För flygresor utgör anslutningsresan ofta under 10 % av resans totala längd men 30% till över 50 % av reseuppoffringen. Anslutningsresan utgör således en signifikant del av den totala reseuppoffringen både i tid och pengar för flyg medan restiden och biljettkostnaden för tåg är en mer komplett beskrivning av hela resan. Resor med tåg startar och slutar ofta i stadsmiljö med närhet till många målpunkter och relativt stort utbud av kollektivtrafik. Det råder därmed en asymmetri i beskrivningen av reseuppoffringen mellan flyg och tåg när man inte tar hänsyn till anslutningsresan.

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  • 26.
    Bergman, Astrid
    et al.
    Trivector Traffic.
    Olstam, Johan
    Swedish National Road and Transport Research Institute, Society, environment and transport, Traffic analysis and logistics. Linköpings universitet, Kommunikations- och transportsystem.
    Allström, Andreas
    Linköpings universitet, Tekniska högskolan.
    Analytical traffic models for roundabouts with pedestrian crossings2011In: Procedia - Social and Behavioral Sciences, ISSN 1877-0428, E-ISSN 1877-0428, Vol. 16, p. 697-708Article in journal (Refereed)
    Abstract [en]

    Roundabouts have become a more common type of intersection in Sweden over the last 30 years. In order to evaluate the roundabout level-of-service both analytical models and simulation models are being used. Analytical traffic models for intersections, such as the Swedish capacity model Capcal, has difficulties estimating the level-of-service of a roundabout if there are pedestrians and cyclists at crossings located close to the roundabout. It is well known that a crossing located after a roundabout exit can cause an up-stream blocking effect that affects the performance of the roundabout. But how the upstream blocking effect depends on the different flows of vehicles and pedestrians is not known. In this paper an existing analytical model by Rodegerdts and Blackwelder has been investigated and compared to simulations in VISSIM and measurements from Swedish roundabouts. The purpose of this investigation is to examine if the model by Rodegerdts and Blackwelder is suitable for implementing into existing analytical models such as Capcal. The results show that the model by Rodegerdts and Blackwelder can estimate if a capacity loss will occur, but the magnitude of this loss is more difficult to evaluate. The conclusion and recommendation is that the model by Rodegerdts and Blackwelder should be implemented into the Swedish capacity model Capcal. The model by Rodegerdts and Blackwelder is to be used as a warning system if the results in Capcal are too uncertain to use for analysis of the roundabout performance.

  • 27.
    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.

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  • 28.
    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.

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  • 29.
    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

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  • 30.
    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.

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  • 31.
    Bång, Karl-Lennart
    et al.
    Kungliga Tekniska Högskolan.
    Olstam, Johan
    Swedish National Road and Transport Research Institute, Society, environment and transport, Traffic analysis and logistics. Linköpings universitet, Kommunikations- och transportsystem.
    Köhler, Joakim
    WSP.
    Wahlstedt, Johan
    Kungliga Tekniska Högskolan.
    Andersson, Jonas
    Tyrens.
    Handbok för kapacitetsanalys med hjälp av simulering2014Report (Other academic)
    Abstract [sv]

    Syftet med föreliggande handbok är att beskriva hur trafiksimulering kananvändas som en alternativ metod eller komplement till analytiska metoderför att bestämma kapacitet och framkomlighet. Liksom metodbeskrivningarnai TRV2013/64343 är beskrivningarna avsedda att kunna användas för att medhjälp av trafiksimulering uppskatta effekterna av en given utformning isamband med planering, konsekvensanalys, projektering och drift avvägtrafikanläggningar. Simulering kan användas som ett komplement till deanalytiska metoderna, eller som ersättning i fall som inte täcks av dessametoder. Härigenom minskas risken för onödiga kostnader förorsakade avsåväl över- som underkapacitet.

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  • 32.
    Böcker, Lars
    et al.
    University of Oslo.
    Priya Uteng, Tanu
    Institute of Transport Economics.
    Liu, Chengxi
    Swedish National Road and Transport Research Institute, Society, environment and transport, Traffic analysis and logistics.
    Dijst, Martin
    Utrecht University.
    Weather and daily mobility in international perspective: A cross-comparison of Dutch, Norwegian and Swedish city regions2019In: Transportation Research Part D: Transport and Environment, ISSN 1361-9209, E-ISSN 1879-2340, Vol. 77, p. 491-505Article in journal (Refereed)
    Abstract [en]

    With climate change, weather has emerged as an important theme in transport research and planning. Although recent studies demonstrate profound weather effects on mobility in single case study areas, international cross-comparisons are required to reveal how effects differ between cities with different transport and climate regimes. This paper provides an international cross-comparison of the simultaneous effects of weather on destination choices, distances, trip chaining, and transport modes in the urban regions of Utrecht (Netherlands), Oslo and Stavanger (Norway), and Stockholm (Sweden). Hereto, regional subsamples of national travel survey data were linked to meteorological records for the three respective countries and analysed in generalised Structural Equation Models. Our findings generally indicate that light, calm, dry and warm atmospheric conditions may positively affect cycling and the selection of outdoor leisure destinations, while cold and to a lesser extent wet and windy weather conditions reduce cycling and enhance car use and travel optimising strategies like trip chaining, to reduce weather exposures. A positive effect of air temperature on cycling flattens out above 20–25 °C in most of our study areas, but hot weather does not seem to reduce cycling strongly. However, our findings also show considerable regional differences in the effects of weather on mobility. Both general effects and differences are interpreted in relation to geographical context, transport and land use, climate conditions, cultures, habits and adaptations and are discussed to formulate policies to mitigate active transport mode users’ exposures to adverse weather and make walking and cycling (even more) year-round modes.

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  • 33.
    Börjesson, Maria
    et al.
    Swedish National Road and Transport Research Institute, Society, environment and transport, Transport economics. KTH.
    Kristoffersson, Ida
    Swedish National Road and Transport Research Institute, Society, environment and transport, Traffic analysis and logistics.
    The Swedish congestion charges: Ten years on2018In: Transportation Research Part A: Policy and Practice, ISSN 0965-8564, E-ISSN 1879-2375, Vol. 107, p. 35-51Article in journal (Refereed)
    Abstract [en]

    Time-of-day dependent cordon-based congestion charging systems were introduced in Stockholm in 2006, and in Gothenburg in 2013. The Stockholm system was significantly extended in 2016, and the peak charge has been increased in the two cities. This paper analyses the effects of the first decade with the Swedish congestion charges, specifically effects of the system updates, and draws policy lessons for the years to come. Should we introduce congestion charges in more cities? Should we extend the systems that we have? We synthesize previous research findings and focus on the long-term effects that have varied over time including the recent years: the price elasticities on the traffic volume across the cordon, the revenue and system operating cost, the public and political support, and consequences for the transport planning process. We also explore the effects on peak and off-peak, and different types of traffic (trucks, company cars and private passenger cars), because of access to novel data that make this analysis possible. We find that the price elasticities have increased over time in Stockholm, but decreased in Gothenburg. We find that the public support increased in the two cities after their introduction until the systems were revised; since then, the public support has declined in both cities. We find that the price elasticity was substantially lower when the charging levels were increased, and when the Stockholm system was extended, than when the charges were first introduced, a likely reason being that the most price-sensitive traffic was already priced off-the road at the introduction.

  • 34.
    Börjesson, Maria
    et al.
    Swedish National Road and Transport Research Institute, Society, environment and transport, Transport economics. Linköping University, Sweden.
    Ragipi Rushid, Ajsuna
    Swedish National Road and Transport Research Institute, Society, environment and transport, Transport economics.
    Liu, Chengxi
    Swedish National Road and Transport Research Institute, Society, environment and transport, Traffic analysis and logistics.
    The impact of optimal rail access charges on frequencies and fares2021In: Economics of Transportation, ISSN 2212-0122, E-ISSN 2212-0130, Vol. 26-27, article id 100217Article in journal (Refereed)
    Abstract [en]

    Sweden has been a front runner in vertical separation. We use data from the business long-distance corridor in Sweden to calibrate and define a demand and supply model. We simulate how the profit, welfare, fares, frequencies, modal shares and train size depend on the level of the track charges. We simulate the welfare optimal track charges, given different levels of congestion on the track, hence using the charges as a pricing instrument to allocate the train slots efficiently. We find that increases in charges have a limited impact on fares but larger impacts on the frequency. When the length of the trains can be extended and when the crowding penalty is high, the impact of higher track charges on the frequencies is larger. Higher track charges increase the length of the trains if possible. The intermodal competition from road and air has a significant impact on rail fares. © 2021 The Authors

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  • 35.
    Cacciabue, Pietro Carlo
    et al.
    KITE Solutions.
    Enjalbert, Simon
    Univ. Lille Nord de France.
    Söderberg, Håkan
    Chalmers University of Technology.
    Tapani, Andreas
    Swedish National Road and Transport Research Institute, Society, environment and transport, Traffic analysis and logistics. Linköpings universitet, Kommunikations- och transportsystem.
    Unified Driver Model simulation and its application to the automotive, rail and maritime domains2013In: Transportation Research Part F: Traffic Psychology and Behaviour, ISSN 1369-8478, E-ISSN 1873-5517, Vol. 21, p. 315-327Article in journal (Refereed)
    Abstract [en]

    This paper describes the implementation of a model of a driver into a computerised numerical simulation. The model is developed to capture the essential characteristics and common aspects of cognition and behaviour of a human being in control of a “vehicle” in different surface transport systems, namely trains, cars and ships. The main functions of the simulation are discussed as well as the experiments carried out in different types of driving simulators to support the estimation of the parameters utilised in the numerical simulation. The validation processes carried out in the rail and maritime domains are also discussed together with a critical review of capacities and limitations of the proposed approach.

  • 36.
    Camén, Carolina
    et al.
    Karlstad Universitet.
    Lidestam, Helene
    Swedish National Road and Transport Research Institute, Society, environment and transport, Traffic analysis and logistics. Linköping Universitet.
    Dominating factors contributing to the high(er) costs for public bus transports in Sweden2016In: Research in Transportation Economics, ISSN 0739-8859, E-ISSN 1875-7979, Vol. 59, p. 292-296Article in journal (Refereed)
    Abstract [en]

    The purpose of this study is to deepen the understanding of what are the underlying reasons for the increasing cost of public transport in general and bus services in particular in a Swedish context. Data were collected through in-depth interviews with managers at the bus operators as well as the authority organizations. This paper contributes by identifying nine categories that can be the dominating factors behind the increasing costs of public bus services in Sweden.

    The identified categories of cost drivers are; of traffic appearance (peak times), greening of buses, age requirements, the contract period, the accessibility customization, special requirements on buses, collective agreements (working time regulation), tendering and contracting process, and finally, counterproductive political governance. It can be concluded that many of the cost drivers originate from the circumstances of the process of public procurement, such as different demands for different regions in Sweden as well as the trade-off between the bus operators' wishes for higher flexibility in the contracts and the traffic authorities' fear of more risks and thereby higher bids in the end.

  • 37.
    Camén, Carolina
    et al.
    Karlstads Universitet.
    Tsaxiri, Panagiota
    Swedish National Road and Transport Research Institute, Society, environment and transport, Traffic analysis and logistics.
    Aldenius, Malin
    Lund University.
    Lidestam, Helene
    Swedish National Road and Transport Research Institute, Society, environment and transport, Traffic analysis and logistics.
    Flexibility in contract design: is that possible?2020In: Research in Transportation Economics, ISSN 0739-8859, E-ISSN 1875-7979, article id 100899Article in journal (Refereed)
    Abstract [en]

    Public procurement is widely used in order to incorporate competition into public services. Competition in procurement often leads to efficiency but the process can also raise some problems. While providing the procurement documents you do not know who will be your upcoming partner. Another aspect is how flexibility can be managed in contract design while maintaining a high service quality. The aim of this study is twofold. Firstly, the aim is to investigate how flexibility has been expressed and historically described in bus tendering documents. Secondly, to explore how the actors define or describe flexibility and its importance in tendering. Data was collected from ten years of tendering documents in the bus sector in Sweden and from interviews and a workshop. The results showed that flexibility in tendering documents has been and still is low for the operators. However, the actors wish for more flexibility and new forms of contracts can make it easier to include higher degrees of flexibility in future contracts. The paper contributes to the ongoing discussion about how to design contracts and to manage flexibility. The study has potential to create knowledge and contribute to better decision making for future procurement of bus transport.

  • 38.
    Carlson, Annelie
    et al.
    Swedish National Road and Transport Research Institute, Society, environment and transport, Environment.
    Björketun, Urban
    Swedish National Road and Transport Research Institute, Traffic and road users, Traffic safety, society and road-user.
    Hammarström, Ulf
    Swedish National Road and Transport Research Institute, Society, environment and transport, Traffic analysis and logistics.
    Utveckling av VTI:s modell för beräkning av trafikarbete på svenska vägar2013Report (Other academic)
    Abstract [en]

    Each year, VTI delivers a description of both a historical description and a prognosis of the annual vehicle mileage using a forecast model. Based on the results from this model a simplified description is made of the future traffic in HBEFA, which is the basis for the annual calculation of traffic emissions. The purpose of this project was to undertake a general revision of the method, both historical and future, in the forecast model. The assessment shows, for example, that a computational model can continually evolve and improve. Recent data have become available through the meter readings for mileage and better data are now available to take into account heavy trucks used for overseas shipments. A function adaptation of mileage as a function of vehicle age shows a good agreement with the measured driving distances for vehicles up to and including about 25 to 30 years of age. A sensitivity analysis of making various assumptions regarding the mileage and age distribution shows the effect on the amount of fuel consumption and regulated emissions for different categories of vehicles.

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  • 39.
    Carlson, Annelie
    et al.
    Swedish National Road and Transport Research Institute, Society, environment and transport, Environment.
    Janhäll, Sara
    Swedish National Road and Transport Research Institute, Society, environment and transport, Environment.
    Hammarström, Ulf
    Swedish National Road and Transport Research Institute, Society, environment and transport, Traffic analysis and logistics.
    Utvärdering PHEM-modellen: En förstudie2013Report (Other academic)
    Abstract [en]

    The Swedish Transport Administration has stated that there is a need to develop the use of micro simulation models of fuel use and emissions of traffic that are used for transport planning. The aim of the project is to perform an evaluation of PHEM model to investigate conditions, opportunities and barriers to use it in transport planning. The following aspects have been assessed: License agreements, costs, rights, property issues; User friendliness; Content and calculation capabilities; Adjustment and development possibilities; Validation. Furthermore, simulation tests have been performed where fuel consumption and emissions of nitrogen oxide, nitrogen monoxide, carbon monoxide, hydrocarbons, particulate mass and particle number has been calculated for roads with different road classes and for additional emissions and fuel use due to a vehicle stop. PHEM model is found to be relatively user-friendly, and with great opportunities to customize calculations. This makes the model complex, therefore it is recommended to start using PHEM with a short introductory course, even for used modellers. A conclusion of the evaluation is a recommendation to use PHEM for transport modelling. The database underlying the engine maps is constantly updated leading to more reliable emission calculations. The possibility to get a greater coherence in the calculations of the exhaust emissions of the different models that the Transport Administration advocate is also improved, which is a positive development. There are, also, some development possibilities that should be considered.

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    Rapport
  • 40.
    Carlsson, Arne
    et al.
    Swedish National Road and Transport Research Institute.
    Tapani, Andreas
    Swedish National Road and Transport Research Institute, Society, environment and transport, Traffic analysis and logistics.
    Rural Highway Design Analysis Through Traffic Micro-Simulation2006In: Proceedings of the 5th International Symposium on Highway Capacity and Quality of Service, Tokyo: JSTE , 2006, p. 249-258Conference paper (Refereed)
    Abstract [en]

    In Sweden, rural roads with separated oncoming lanes are becomingincreasingly important due to their superior safety properties.The level-of-service of such roads may however be reduced since traffic is restricted by the barrier between the oncoming lanes.This level-of-service impact can be evaluated through traffic microsimulation.Such simulation based assessments of rural highways require simulation models capable of modeling rural road traffic.This paper presents a simulation study of different rural road designs with separated oncoming lanes using a rural road traffic simulationmodel. The presentation illustrates the use of simulationfor rural highways and the result of the study indicates that oncominglane separation is a competitive alternative despite slightlevel-of-service reductions compared to undivided two-lane highways.

  • 41.
    Carlsson, Arne
    et al.
    Swedish National Road and Transport Research Institute, Society, environment and transport, Enviroment and traffic analysis.
    Wiklund, Mats
    Trafikanalys.
    Olstam, Johan
    Swedish National Road and Transport Research Institute, Society, environment and transport, Traffic analysis and logistics.
    Tapani, Andreas
    Swedish National Road and Transport Research Institute, Society, environment and transport, Traffic analysis and logistics.
    Metod för beräkning av fördröjningar på vägavsnitt utan omkörningsmöjlighet2013Report (Other academic)
    Abstract [en]

    This VTI report presents a method for calculating expected queue length and travel time delay on one lane road sections without overtaking possibilities. The method was developed 2001 and presented in a working paper. The background for the model development was that the Swedish Road Administration (now the Swedish Transport Administration) planned to build so called 1+1 roads, i.e. roads with longer sections without overtaking possibilities. The method developed has later on also shown to be valuable for level of service calculations of 2+1 roads with varying share of two lane sections and for developing speed-flow relationships for the Administration’s ”Effect calculations for road facilities”. The method uses section length, traffic flow, average speed and standard deviation as input. The method is divided with respect to calculation of effects due to single slowrunning vehicles and effects at “normal” speed distribution. Since no data were available when the model was developed, the model results were instead compared to traffic simulations with the microscopic traffic simulation model AIMSUN. The results show a good correlation but the analytical model gives in general approximately 1.2 per cent lower travel time delay. The differences can probably partly be explained by the stochastic parts of the simulation model. One should also remember that neither the analytical model nor the simulation model has been calibrated and validated with real data for this type of roads. Thus, the differences between the models do not necessary imply that the analytical model is the one deviating from reality.

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  • 42.
    Daniels, David
    et al.
    Chalmers tekniska högskola.
    Danilovic, Mike
    Högskolan i Halmstad.
    Wehner, Jessica
    Swedish National Road and Transport Research Institute, Society, environment and transport, Traffic analysis and logistics.
    Käck, Svetla
    Swedish National Road and Transport Research Institute, Traffic and road users, Vehicle Systems and Driving Simulation..
    Nordin, Lina
    Swedish National Road and Transport Research Institute, Infrastructure, Infrastructure maintenance.
    Regeringsuppdrag om elektrifieringen av transporter: samspelet mellan energisystemet och transportsystemet2022Report (Other academic)
    Abstract [en]

    The Swedish National Road and Transport Research Institute (VTI) has been commissioned by the Swedish Government to “contribute to the creation of knowledge regarding a rapid, smart and socioeconomically efficient electrification of the transport sector”. This report presents the part of the commission that describes a general analysis of the interaction between the energy system and the transport system, what obstacles there are and what solutions can contribute to increased electrification of transport. This part of the assignment includes good examples from other countries. 

    Transport and energy have always been closely linked sectors. What is changing now, is not only the connection between the sectors, but also their nature; while the transport sector has historically mainly consumed oil products, global climate measures will drive the transport sector towards a stronger link to electricity. Therefore, the transition from oil-based transport to electricity-based transport is as much about sector changing within the energy sector as between energy and transport sectors. To handle this transition requires a conversion of both systems. The report describes the implications of the transport sector’s change on the energy system and the roles of various actors in the change. In addition, good examples from four other countries – China, the USA, Norway and the Netherlands – are highlighted. When transitioning, there are some policy aspects that are important to take into account, such as technology and behavior change, changes in the sectors and overlapping political goals.

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  • 43.
    Daniels, David
    et al.
    Swedish National Road and Transport Research Institute, Society, environment and transport, Traffic analysis and logistics.
    Yeh, Sonia
    Chalmers University of Technology, Sweden.
    Complexities in the energy-transport co-transformation2022In: Progress in Energy, ISSN 2516-1083, Vol. 4, no 4, article id 040201Article in journal (Refereed)
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  • 44.
    Dukic, Tania
    et al.
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Ahlström, Christer
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Björketun, Urban
    Swedish National Road and Transport Research Institute, Traffic and road users, Traffic safety, society and road-user.
    Kettwich, Carmen
    Karlsruhe Institute of Technology.
    Yahya, Mohammad Reza
    Swedish National Road and Transport Research Institute, Society, environment and transport, Traffic analysis and logistics.
    Patten, Christopher
    Swedish National Road and Transport Research Institute, Traffic and road users, Human-vehicle-transport system interaction.
    Tapani, Andreas
    Swedish National Road and Transport Research Institute, Society, environment and transport, Traffic analysis and logistics.
    Vadeby, Anna
    Swedish National Road and Transport Research Institute, Traffic and road users, Traffic safety, society and road-user.
    Inverkan av elektroniska reklamskyltar på trafiksäkerhet: en studie på E4 i Stockholm2011Report (Other academic)
    Abstract [en]

    The present report presents four studies that were conducted with the aim to evaluate how electronic billboards (ERS) affect traffic safety. Study 1 is a literature review to examine how billboards impact road safety. The conclusions from the review showed that animated pictures and the location of the billboards have a major impact on driver behaviour as well as that darkness and adverse weather conditions can create glare which makes driving difficult especially for older drivers.

    The second and third studies compared the speed and the number of accidents before and after the installation of the billboards. Neither difference in traffic volume nor in average speed could be demonstrated. There was nothing in the studied accidents to suggest that the accident was affected by a billboard.

    The fourth sub-study is a field study investigating 41 drivers (driving and visual behaviour) on the E4 as they pass the billboards. Results showed several cases of visual distraction. The results also show a negative attitude to the billboards for a majority of the drivers.

    In summary, no effects from the billboards on traffic safety could be showed at the macro level. However, the effects of visual distraction must be taken into consideration and investigated further before deciding whether billboards will be implemented on Swedish roads.

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  • 45.
    Dukovska-Popovska, Iskra
    et al.
    Materials and Production, Aalborg University, Denmark.
    Kjellsdotter Ivert, Linea
    Swedish National Road and Transport Research Institute, Society, environment and transport, Traffic analysis and logistics.
    Jónsdóttir, Hafdís
    Chalmers Industriteknik, Göteborg, Sweden.
    Dreyer, Heidi Carin
    Department of Industrial Economics and Technology Management, Norwegian University of Science and Technology, Trondheim, Norway.
    Kaipia, Riika
    University of Turku, Finland.
    The supply and demand balance of recyclable textiles in the Nordic countries2023In: Waste Management, ISSN 0956-053X, E-ISSN 1879-2456, Vol. 159, no March, p. 154-162Article in journal (Refereed)
    Abstract [en]

    The textile industry is on its early steps towards circular economy. Being a highly resource-intensive and waste-generating industry, it is essential to embrace fiber-to-fiber recycling in addressing the increasing textile waste problem. Several innovative initiatives are happening within this area, not least in the Nordic countries, where automated sorting and fiber-to-fiber recycling technologies and capacities are developing. These large investments require economy of scale; however, this is challenged by the fractioned supply due to the specific fiber requirements of the recycling facilities. To ensure economy of scale and support strategic planning, it is important to investigate the balance of the demand of those capacities with the supply of recyclables generated in the region. Local and regional perspectives are needed in order to avoid unnecessary transportation of low value materials. Based on a synthetises of existing textile flow studies and interviews with relevant actors in four Nordic countries, this study investigates the balance between the supply of recyclable textiles and the sorting and recycling capacity. This is accomplished by estimating the volumes of recyclables and their fiber composition (based on developed weighting average method) and comparing these with the current and upcoming capacities in each country and in the Nordics as a whole. The findings indicate that the upcoming automatic sorting and recycling capacity will be sufficient to deal with the total recyclable fraction in the Nordic region, except for some of the synthetic fibers. However, there are imbalances between supply and demand within individual countries, highlighting opportunities for collaboration.

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  • 46.
    Egeskog, Johan
    et al.
    Swedish National Road and Transport Research Institute, Infrastructure, Infrastructure maintenance.
    Niska, Anna
    Swedish National Road and Transport Research Institute, Infrastructure, Infrastructure maintenance.
    Pérez Castro, Guillermo
    Swedish National Road and Transport Research Institute, Society, environment and transport, Traffic analysis and logistics.
    Kircher, Katja
    Swedish National Road and Transport Research Institute, Traffic and road users, The Human in the Transport system..
    Olstam, Johan
    Swedish National Road and Transport Research Institute, Society, environment and transport, Traffic analysis and logistics.
    Johansson, Fredrik
    Swedish National Road and Transport Research Institute, Society, environment and transport, Traffic analysis and logistics.
    Cyklisters utrymmesbehov: kunskapsunderlag till rekommendationer för utformning2023Report (Other academic)
    Abstract [en]

    During the fall of 2021, the Swedish Transport Agency was commissioned by the Swedish Government to analyze and, if necessary, submit proposals for how changed traffic rules could lead to an increase in the proportion of road users who travel by bicycle. Against this background, the Swedish Transport Agency has engaged VTI, the Swedish Road and Transport Research Institute, to assist in the work by describing the state of knowledge based on current research in the relevant areas.

    The aim of this study has been to investigate the spatial requirements of cyclists in different traffic situations and develop a basis for recommendations for designing cycling infrastructure regarding widths. Today, there are no rules or common construction practices for the physical design of cycle paths or cycle lanes in Sweden. Instead, it is up to each road authority to produce their own cross sections or recommendations and follow up on compliance.

    The results in this report are based on literature studies regarding design standards and research on spatial requirements of cyclists. Recommendations are presented on minimum widths of cycle paths and cycle lanes depending on the possibility of meetings and overtaking, including consideration of cargo bikes, as well as safe distances to obstacles beside the road. An approach to model structure for assessing spatial requirements at higher flows of cyclists has also been developed.

    The width of cycle paths can be varied depending on the desired dimensioning traffic situation. The dimensioning traffic situation is defined as the possibility of safe meetings or overtaking of a certain number of cyclists and pedestrians simultaneously on a cycle path or mixed-use path. From a maintenance perspective, however, it is advantageous to build bicycle infrastructure with a width of at least 2.5 meters, regardless of the traffic situation. Less width than that can result in lower efficiency for operation and maintenance with increased life cycle costs as a result.

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  • 47.
    Ekström, Joakim
    et al.
    Linköpings universitet.
    Ericsson, Eva
    WSP.
    Olstam, Johan
    Swedish National Road and Transport Research Institute, Society, environment and transport, Traffic analysis and logistics.
    Persson, Anna
    WSP.
    Metodik för beräkning av emissioner baserat på trafikdata från dynamiska trafikmodeller och trafikmätningar2021Report (Other academic)
    Abstract [sv]

    Projektet syftade till att ta fram en metod för tillämpning av HBEFA på trafikdata från mätningar och dynamiska trafikmodeller på ett sätt som är konsistent med den tillämpning av HBEFA som idag sker med statisk trafikdata. Projektet fokuserade främst på tillämpningar där lokala emissioner från vägtrafik är av intresse. Exempel på sådana tillämpningar är uppföljning, estimering och prediktering av luftkvalitet. Men även analys av förändring av utsläpp från vägtrafiken över tid, samt före/efter studier vid förändringar av trafikinfrastrukturen. 

    I HBEFA är skattning av trafiktillstånd centralt för estimering av emissioner. I denna studie har vi studerat och jämfört tre olika sätt att definiera trafiktillståndet i HBEFAs trafiksituationer nämligen baserat på:

    • flöde (det som används i nuläget)
    • hastighet
    • densitet

    Flödesbaserade definitioner har en inbyggd begränsning i att de inte entydigt kan beskriva trafiksituationen, då lågt flöde kan innebära både låg trängsel och hög trängsel, beroende på hastighet. Detta är inget problem i nuvarande tillämpning av HBEFA med statisk trafikdata, då en förenklad beskrivning av det överbelastade fallet görs, som tillåter flöden över kapaciteten, men som då representerar en efterfrågan snarare än flöde. Undersökningarna i denna studie indikerar att en hastighetsbaserad definition av trafiktillstånd inte är att föredra då hastigheten kan variera relativt mycket mellan olika fordon och över en sträcka vid liknande flödes- och densitetsförhållanden. Hastighetsbaserade gränser mellan trafiktillstånd blir främst problematiskt vid tillämpning på mätdata. Vid hastighetsbaserade gränser blir varje fordonspassage med låg hastighet automatiskt klassade i ett trafiktillstånd som innebär trängsel. Densitet är ett mer stabilt mått vid liknande trafikförhållanden och kan sägas bättre definiera graden av trängsel i trafikteoretisk mening. 

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  • 48.
    Elyasi-Pour, Roya
    Swedish National Road and Transport Research Institute, Society, environment and transport, Traffic analysis and logistics. Linköpings universitet.
    Driving behavior model in a simulation based evaluation approach for Look Ahead Cruise Control2014Conference paper (Other academic)
  • 49.
    Elyasi-Pour, Roya
    et al.
    Swedish National Road and Transport Research Institute, Society, environment and transport, Traffic analysis and logistics. Linköpings universitet, Kommunikations- och transportsystem.
    Olstam, Johan
    Swedish National Road and Transport Research Institute, Society, environment and transport, Traffic analysis and logistics. Linköpings universitet, Kommunikations- och transportsystem.
    Utvärdering av förarstödsystem baserat på sammankoppling av trafiksimulering och fordonsimulering2014Conference paper (Other academic)
  • 50.
    Engholm, Albin
    et al.
    KTH Royal Institute of Technology.
    Björkman, Anna
    KTH Royal Institute of Technology.
    Joelsson, Yuri
    KTH Royal Institute of Technology.
    Kristoffersson, Ida
    Swedish National Road and Transport Research Institute, Society, environment and transport, Traffic analysis and logistics.
    Pernestål, Anna
    KTH Royal Institute of Technology.
    The emerging technological innovation system of driverless trucks2020In: Transportation Research Procedia, Elsevier B.V. , 2020, p. 145-149Conference paper (Refereed)
    Abstract [en]

    Driving automation technology is attractive for the road freight transport sector since driverless trucks (DL-trucks) may drastically reduce driver costs, increase truck utilization and improve road safety. Although DL-trucks may bring significant impacts to the transport system, research on the future diffusion and impacts of DL-trucks is scarce compared to passenger transport. In this paper the sociotechnical innovation system developing, diffusing and utilizing DL-trucks in Sweden is analyzed based on the technological innovation systems (TIS) framework. The analysis is based on 20 expert interviews with a total of 23 representatives from 16 actors in the DL-truck TIS in Sweden. The TIS analysis shows that there are significant uncertainties in the timeline, operational capabilities, infrastructure requirements and regulative landscape for a widespread DL-truck deployment. There is a general view among the interviewees that DL-trucks is an important opportunity for Swedish industry and the economy. From a transport system perspective, DL-trucks are expected to bring sustainability benefits but it remains uncertain whether these benefits will be realized and what the negative side effects might be. The development of DL-trucks is heavily influenced by incumbent firms in the truck manufacturing industry but new actors from the telecom sector, energy sector and emerging truck technology companies are entering the area and shaping the development. The current relatively rigid institutions for truck manufacturing and road freight transport will require significant alignment to adapt to DL-truck operations in areas such as laws and regulations, business models and operational practices. The value chain of road freight transport may be disrupted as some of the current key actors, for instance traditional road carriers, could become less relevant in future DL-truck value chains. A critical uncertainty is how and by which actors the setting of requirements, deployment and financing of digital infrastructure for DL-trucks will be done.

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