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  • Oldbury, Kelsey
    et al.
    Swedish National Road and Transport Research Institute, Society, environment and transport, Mobility, actors and planning processes.
    Isaksson, Karolina
    Swedish National Road and Transport Research Institute, Society, environment and transport, Mobility, actors and planning processes.
    Elstation Stockholm C: användares erfarenheter2018Report (Other academic)
    Abstract [en]

    Current discussions concerning the development of sustainable transport often focus on the importance of shared and combined mobility options. In recent years, various types of initiatives have been launched with the intention of promoting the development of such ideas. Urban carpools are one such mode of transport and in Stockholm the electric carpool parking station, directly adjacent to Stockholm’s central train station, has been used as a parking and charging location for the collection and drop-off of both “fixed” and “floating” carpool vehicles during the period October 2016 to December 2017.

    One question of specific importance is how carpools are perceived by users when trying to understand the role this type of initiative plays in achieving sustainable mobility. This report presents the results of a focus group interview study conducted with a selection of people who have used various carpool services at the Stockholm Central electric carpool station.

    The purpose of the study was to gain a deeper the insight into the users' perspectives and experiences of carpool services in general, and more specifically how they experienced the electric carpool station at Stockholm’s Central station.

    The results from this study confirm a common aim for the development of carpool services, namely that this type of service should allow people to refrain from owning a car. However, our material also indicates that there are still practical barriers that make it difficult for specific groups to use a carpool, such as families with small children. These practical challenges need to be developed and overcome in order to encourage increased usage of carpools and car sharing services.

  • Odolinski, Kristofer
    et al.
    Swedish National Road and Transport Research Institute, Society, environment and transport, Transport economics.
    Yarmukhamedov, Sherzod
    Riksrevisionen.
    Nilsson, Jan-Eric
    Swedish National Road and Transport Research Institute, Society, environment and transport, Transport economics.
    Haraldsson, Mattias
    Swedish National Road and Transport Research Institute, Society, environment and transport, Transport economics.
    The marginal cost of track reinvestments in the Swedish railway network: using data to compare methods2018Report (Other academic)
    Abstract [en]

    In this study, we analyze the difference between survival and corner solution models in estimating the marginal cost of reinvestments. Both approaches describe the reinvestment process in rather intuitively similar ways but have several methodological distinctions. We use Swedish railway data on track segment and section levels over the period 1999-2016 and focus on reinvestments in track superstructure. Results suggest the marginal costs from survival and corner solution models are SEK 0.0041 and SEK 0.0103, respectively. The conclusion is that the corner solution model is more appropriate, as this method consider the impact traffic has on the risk of reinvestment as well as on the size of the reinvestment cost. The survival approach does not consider the latter, which is problematic when we have systematic variations in costs due to traffic and infrastructure characteristics.

  • Johansson, Fredrik
    et al.
    Swedish National Road and Transport Research Institute, Society, environment and transport, Traffic analysis and logistics.
    Pyddoke, Roger
    Swedish National Road and Transport Research Institute, Society, environment and transport, Transport economics.
    Interaction delay and marginal cost in Swedish bicycle traffic2018Report (Other academic)
    Abstract [en]

    We apply the method presented by Johansson (2018) to estimate a volume delay function and marginal cost for bicycle traffic on cycling paths separated from motorized traffic based on point measurements of speed and lateral positions from seven sites in Sweden. The results indicate that a quadratic volume – delay function fits the data well in the observed range of volumes, and that there are significant delays already at volumes far below the capacity due to the heterogeneity of the desired speed over the population. The total marginal cost of delay per unit flow is estimated to €9×10-5 h/km.

  • Johansson, Fredrik
    Swedish National Road and Transport Research Institute, Society, environment and transport, Traffic analysis and logistics.
    Estimating interaction delay in bicycle traffic from point measurements2018Report (Other academic)
    Abstract [en]

    Planning for bicycle traffic is getting increasingly popular in cities, often motivated by that it is beneficial for the environment and the public health, and that it is a space efficient mode of transport. However, research on bicycle traffic has traditionally focused mainly on safety and mode choice, and less on traffic engineering topics such as investigating travel times, delays, and capacities. This study contributes to filling this gap by presenting a general method to estimate a volume -- delay function for bicycle traffic based on point measurements of passage time, speed, and lateral position, and, using estimates of the value of time in bicycle traffic, estimating the marginal cost of the interaction delay.

    The proposed method is based on an established method to estimate the distribution of desired speeds, and extends this to estimate the delay of the observed cyclists. The method is demonstrated using a data set from a bridge in Stockholm, Sweden, showing that there is significant interaction delay and associated cost even for relatively modest volumes, implying that interaction delay and its cost should be considered when planning for bicycle traffic.

  • Johansson, Magnus
    et al.
    Swedish National Road and Transport Research Institute, Society, environment and transport, Transport economics.
    Johansson, Oskar
    Swedish National Road and Transport Research Institute, Society, environment and transport, Transport economics.
    Internalisering av godstrafikens externa effekter – konsekvensanalyser med Samgodsmodellen: en delrapport inom SAMKOST 32018Report (Other academic)
    Abstract [en]

    VTI has been commissioned to review the current knowledge of social marginal costs for using the country’s national infrastructure, Government Decision N2017/01023/TS. As a part of this commission VTI is asked to assess the effects of a full internalisation of external costs within the transport sector.

    In this report the effects on freight transports of gods being traded within and to/from Sweden is assessed using the Swedish national freight flow model Samgods. The analysis includes calculating the appropriate levels of tax and/or fees needed for decisionmakers in the freight transport market to fully take in to account the external effects of traffic with different types of vehicles. In a second step the freight flow model is used to estimate effects on ton-kilometers transported on road, rail and sea respectively.

    Results show that the resulting change in relative costs for transporting with different modes of transport will increase ton-kilometers transported by sea. A full internalization of external cost will decrease ton-kilometer transported by rail and on road. The largest decrease being calculated for rail. To fully take account for external effects track fees in Sweden will have to be four times higher. In total we estimate a small but positive effect on the climate.

  • Nilsson, Jan-Eric
    et al.
    Swedish National Road and Transport Research Institute, Society, environment and transport, Transport economics.
    Haraldsson, Mattias
    Swedish National Road and Transport Research Institute, Society, environment and transport, Transport economics.
    Redovisning av regeringsuppdrag kring trafikens samhällsekonomiska kostnader: SAMKOST 32018Report (Other academic)
    Abstract [en]

    Starting in 2013, VTI has been tasked with three government missions to improve knowledge about the traffic's socioeconomic costs. SAMKOST 3 has covered all modes of transport, but focus has been on maritime transport and aviation. The main purpose of the analysis is to improve the knowledge about the external costs of the traffic i.e. costs of accidents, congestion, noise, air pollution and climate impact. This final report summarizes the results of the sub-reports that have been prepared to meet the purpose. An important part of the analysis has been an in-depth discussion of the role of Sweden’s carbon dioxide tax on fuels to limit emissions.

  • Pyddoke, Roger
    Swedish National Road and Transport Research Institute, Society, environment and transport, Transport economics.
    Cykelflödesvariationer i Stockholm och Göteborg: delrapport inom SAMKOST 32018Report (Other academic)
    Abstract [en]

    The purpose of this project is to clarify the possibilities and the need for a pilot study aimed at measuring the marginal cost of congestion on bicycle paths. The goal of the measurements are exclusively to quantify the value of the delay caused by one further cyclist being present on the bicycle path. Ultimately, the goal is to be able to evaluate measures to broaden or otherwise improve the bicycle infrastructure.

    This memorandum describes variations in cycle flow over a longer period of time, over one year and over a day (during months and days with high flows) in Stockholm and Gothenburg, with the aim to estimate when measurements should be made of the extent and intensity of significant congestion on bicycle paths.

    Cycle flows vary by approximately a factor of 4 in Stockholm during the year in places with large flows and slightly less in Gothenburg, about a factor of 3. During peak hours, cycling flows show large variation during a day with shorter periods of high flows in the morning and afternoon.

    The presence of costly congestion can therefore be expected to be quite short in Sweden's two largest cities. An example indicates that at 20 percent of all bicycle passages across the Liljeholmen bridge in Stockholm, the cyclist experiences high levels of presence of other cyclists. However, this example is not claimed to be representative either this or other locations in the inner city of Stockholm.

  • Sandin, Jesper
    Chalmers University of Technology.
    Aggregating Case Studies of Vehicle Crashes by Means of Causation Charts: An Evaluation and Revision of the Driving Reliability and Error Analysis Method2008Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    There is a need for increased knowledge about causes to motor-vehicle crashes and their prevention. Multidisciplinary in-depth case studies can provide detailed causation data that is otherwise unattainable. Such data might allow the formulation of hypotheses of causes and causal relationships for further study. By converting the data into causation charts that are aggregated, common causation patterns would give greater weight to such hypotheses. However the charts must first be compiled by means of a systematic analysis method, which requires three parts; a model, a classification scheme and a classification method.

    Four general accident models were evaluated and found inadequate to form the basis for a causation analysis method. This was primarily because the models in practice treat road-users, vehicles and traffic environment as separate components, but also due to the focus on events immediately prior to the crash and either static, sequential, or absent modelling of interaction.

    Two studies were carried out to evaluate whether case files could be aggregated by means of charts that had been compiled with the Driving Reliability and Error Analysis Method (DRE AM). In DREAM, contributory factors (genotypes) are systematically analysed, classified and linked in a single chart for each driver that illustrate the causes of a critical event (phenotype). In the first study, case files from 38 single-vehicle crashes were examined to distinguish crashes with similar circumstances. Four types of loss of vehicle control were identified, for which the associated DREAM charts were aggregated. The results revealed common patterns within the types, as well as different patterns between them. The second study focused on 26 intersection crashes. Based on the most common violations at intersections, six risk situations were defined, and the DREAM charts associated with each risk situation were aggregated. A common pattern in each of two risk situations indicated that drivers with and without the right of way had not seen the other vehicle due to distractions and/or sight obstructions. A frequently occurring pattern for the drivers with the right of way was that they had not expected another vehicle to cross their path. The absence of clear patterns in three risk situations was a result of a low number of charts and rather unique circumstances in these cases. Parts of the aggregated charts contained an unexpectedly large variation, identified as a consequence of inconsistently compiled charts.

    Prior the final study assessing intercoder agreement, DREAM was revised into a new version based on the experience from the latter aggregation study. A total of seven investigators from four European countries compiled seven DREAM charts for each driver involved in four types of accidents. The results indicated that the intercoder agreement for genotypes ranged from 74% to 94% with an average of 83%, while it for phenotypes ranged from 57% to 100% with an average of 78%. This acceptable level of agreement is expected to rise with enhanced training. The present thesis thus shows that DREAM is a highly promising method for the compilation of causation charts. Future studies are expected to benefit from aggregating DREAM charts when formulating hypotheses of general causes and causal relationships as a subject for further research, as well as to identify alternative countermeasure strategies.

    List of papers
    1. Understanding the causation of single-vehicle crashes: A methodology for in-depth on-scene multidisciplinary case studies
    Open this publication in new window or tab >>Understanding the causation of single-vehicle crashes: A methodology for in-depth on-scene multidisciplinary case studies
    2007 (English)In: International Journal of Vehicle Safety, ISSN 1479-3105, Vol. 2, no 3, p. 316-333Article in journal (Refereed) Published
    Abstract [en]

    Knowledge of the interaction between and consequences of causation factors is essential when designing active safety measures. There is frequently a lack of adequate details in the area of causation, especially pertaining to Single-Vehicle Crashes (SVCs). This study describes the in-depth and on-scene investigations of 38 SVCs that took place in Gothenburg, Sweden. The causation factors involved were analysed using the Driving Reliability and Error Analysis Method (DREAM). The 38 SVCs were grouped into four scenarios. In the first scenario, vehicles drifted out of lane due to driver fatigue, sleepiness or distraction. In the second, an undetectable reduction in road friction caused experienced drivers to lose control in curves. Loss of control in curves was also a factor in scenario three, partly due to high speed. In this scenario, drivers overestimated their driving skills or had limited experience of the vehicle or the curve. In the final scenario, alarmed drivers lost control as a result of excessive steering-wheel manoeuvres. This study demonstrates a methodology that can be used to explain how a combination of factors may increase the risk of SVCs.

    National Category
    Vehicle Engineering
    Identifiers
    urn:nbn:se:vti:diva-13355 (URN)10.1504/IJVS.2007.015546 (DOI)2-s2.0-64249137108 (Scopus ID)
    Available from: 2018-10-31 Created: 2018-10-31 Last updated: 2018-10-31Bibliographically approved
    2. Accident Models for Modern Road Traffic: Changing Times Creates New Demands
    Open this publication in new window or tab >>Accident Models for Modern Road Traffic: Changing Times Creates New Demands
    2004 (English)In: Proceedings of the International Conference on Systems, Man and Cybernetics, 2004Conference paper, Published paper (Other academic)
    Abstract [en]

    The purpose of this study is to develop accident models that can be applied to modern road traffic. Several criteria are proposed that a model suitable for the conditions of modern road traffic should fulfil. Four commonly applied general accident models are reviewed, and found to be inadequate in relation to the criteria. Also, the consequences of an underlying structural problem in all four model types, which is the result of regarding the human as a system component, are discussed. To remedy the discovered problems, it is argued that traffic safety should make use of the developments that have been made in the field of industrial safety. Several suggestions are proposed for how a new model could be developed, based on experiences from industrial safety.

    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:vti:diva-13356 (URN)10.1109/ICSMC.2004.1398310 (DOI)
    Conference
    International Conference on Systems, Man and Cybernetics. October 10-13, The Hague, The Netherlands
    Available from: 2007-02-26 Created: 2018-10-31 Last updated: 2018-10-31Bibliographically approved
  • Vierth, Inge
    Swedish National Road and Transport Research Institute, Society, environment and transport, Transport economics.
    Organization of pilot and icebreaking in the Nordic countries and update of the external costs of sea transports in Sweden: a report in SAMKOST 32018Report (Other academic)
    Abstract [en]

    The Swedish government has commissioned VTI to review current knowledge of the external costs for all modes of transport. This report is the third part of the government commission (Samkost 3), it addresses sea transports where the access to data and the knowledge level is generally lower than for the land-based modes. One finding in the government commission 2016 (Samkost 2) was that the possibilities to apply the external cost estimates for pricing are rather limited in the existing organizational structures. This report comprises two parts. Part 1 addresses the organization models of piloting and icebreaking in Denmark, Finland, Norway and Sweden. The Nordic countries have chosen different organization models to provide these services that can influence the capacity and service levels, the cost structure, the cost effectiveness and the pricing of the services. Part 2 updates the costs of pilot and icebreaking services and the external costs related to traffic safety, greenhouse gases and air pollution caused by sea transports in Swedish waters from Samkost 2 (2014 prices and valuations) to Samkost 3 (2017 prices and valuations). The calculated total external costs per year are lower in Samkost 3 than in Samkost 2: about five percent in the low alternative and about ten percent in the high alternative. This implies that the internalization is about 100 percent which is higher than in Samkost 2. The external costs caused by the transports in international waters are probably are internalized to a low extent and national and international policies are needed to reach e.g. national and international climate objectives.

  • Andersson-Sköld, Yvonne
    et al.
    Swedish National Road and Transport Research Institute, Society, environment and transport, Environment.
    Johannesson, Mikael
    Swedish National Road and Transport Research Institute, Society, environment and transport, Environment.
    Uppfyllelse av klimat- och miljömål vid en fullständig internalisering av vägtrafikens samhällsekonomiska kostnader: en delrapport inom SAMKOST 32018Report (Other academic)
    Abstract [en]

    On the 9 February 2017, The National Road and Transport Research Institute (VTI) received the governmental commission to continue previous research on socio-economic costs of traffic by developing new knowledge and update the existing knowledge base. As part of this mission, an assessment of the impact on the climate and the national environmental objectives of internalizing external costs was included. The transport sector has a direct or indirect impact on virtually all Swedish environmental quality objectives. This report focusses on road traffic and the environmental quality objectives that were considered in the previous governmental commission SAMKOST 2 and where relevant quantifiable targets, specifications and indicators were available: Limited climate impact, Fresh air, Only natural acidification, No eutrophication and noise as a part of the environmental quality objective Good built environment.

    According to results presented in this report, a taxation corresponding to 100 percent internalization would, if imposed in 2016, contribute to a 2 percent (ca 0,4 million ton) decrease in emissions of carbon dioxide 2030 in comparison to current internalization degrees. Such an estimated change is small in relation to the calculation uncertainties due to for example uncertainties about traffic development, price elasticity, technological development, economic development, the development of prices of oil etc. To achieve the objective of reducing greenhouse gas emissions from domestic transport (except aviation) by 70 percent by year 2030 compared with 2010, would need additional instruments and measures than those which have already been decided to reduce the emissions by a further 1–3 million ton or 5–15 percent. An increase in the current carbon dioxide tax from SEK 1.14 per kg of carbon dioxide to SEK 2 per kg of CO2 will reduce emissions by an additional 1.6 million ton or 8 percent more than achieved with current degree of internalization (all other aspects alike). In combination with the already decided instruments, an increase in the carbon tax with SEK 1 per kg carbon dioxide for passenger cars implies that the target of reducing emissions from domestic transport by 70 percent from year 2010 level to 2030 can be reached. For future emissions of nitrogen oxides, a 100 percent internalization, or increased CO2 tax, will only result in a marginal impact.

  • Eriksson, Jenny
    et al.
    Swedish National Road and Transport Research Institute, Traffic and road users, Traffic Safety and Traffic System.
    Lindborg, Eva
    Trafikanalys.
    Adell, Emeli
    Trivector.
    Holmström, Andreas
    Trafikanalys.
    Silvano, Ary P.
    Swedish National Road and Transport Research Institute, Traffic and road users, Traffic Safety and Traffic System.
    Nilsson, Annika
    Trivector.
    Henriksson, Per
    Swedish National Road and Transport Research Institute, Society, environment and transport, Mobility, actors and planning processes.
    Wiklund, Per
    Trafikanalys.
    Dahlberg, Lina
    Trivector.
    Nya sätt att samla in inviduell resvaneinformation: Utvärdering av insamlings- och rekryteringsmetoder2018Report (Other academic)