Transportation Research Record

Journal: Transportation Research Record

Abbreviation

Transp. Res. Rec.

Publisher

SAGE

ISSN

0361-1981
2169-4052

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Publications 1 - 10 of 48

Integration of activity-based and agent-based models
Bekhor, Shlomo; Dobler, Christoph; Axhausen, Kay W. (2011)
Transportation Research Record
Multimodal Commuting to Work by Public Transport and Bicycle
Heinen, Eva; Bohte, Wendy (2014)
Transportation Research Record
Public transport and cycling often are combined in one trip. However, this combination has not attracted much research attention. Existing research has identified several hard factors that may explain the combined use of public transport and bicycle: station accessibility, distance to the station, and bicycle facilities at stations. Even though the effect of attitudes toward mode choice is widely acknowledged, the authors are not aware of any study that analyzes this effect on the combined use of bicycle and public transport. The effect of attitudes on the decision to commute by both public transport and bicycle was investigated. Results indicated that public transport–bicycle commuters differed significantly from those who commuted by only car, public transport, or bicycle. Nevertheless, public transport–bicycle commuters shared similarities with public transport commuters (who did not cycle to or from the station) and bicycle commuters. Public transport commuters had a more positive attitude toward car commuting and a less favorable attitude toward cycling, and bicycle commuters had a more positive attitude toward cycling and a less favorable attitude toward public transport than did public transport–bicycle commuters. Public transport–bicycle commuters also shared most beliefs about public transport with public transport commuters and shared beliefs about cycling with bicycle commuters and public transport commuters but differed on several characteristics. Nevertheless, differences between the groups were significant and indicated that commuters who used both public transport and a bicycle in one trip were different from single-mode commuters.
MFC free-flow model
Makridis, Michail; Fontaras, Georgios; Ciuffo, Biagio; et al. (2019)
Transportation Research Record
Free-flow movement of vehicles in microsimulation software is usually defined by a set of equations with no explicit link to the instantaneous dynamics of the vehicles. In some cases, the car and the driver are modeled in a deterministic way, producing a driving behavior, which does not resemble real measurements of car dynamics or driving style. Depending on the research topic, the interest in microsimulation is to capture traffic dynamics phenomena, such as shockwave propagation or hysterisis. Existing car-following models are designed to simulate more the traffic evolution, rather than the vehicle motion, and consequently, minimal computational complexity is a strong requirement. However, traffic-related phenomena, such as the capacity drop are influenced by the free-flow acceleration regime. Furthermore, the acceleration pattern of a vehicle plays an essential role in the estimation of the energy required during its motion, and therefore in the fuel consumption and the CO2 emissions. The present work proposes a lightweight microsimulation free-flow acceleration model (MFC) that is able to capture the vehicle acceleration dynamics accurately and consistently, it provides a link between the model and the driver and can be easily implemented and tested without raising the computational complexity. The proposed model is calibrated, validated, and compared with known car-following models on road data on a fixed route inside the Joint Research Centre of the European Commission. Finally, the MFC is assessed based on 0–100 km/h acceleration specifications of vehicles available in the market. The results prove the robustness and flexibility of the model.
Impact of Settlement Size and Regional Density on the Frequency of Different Holiday Types
Scheffler, Tanja; Heinen, Eva (2024)
Transportation Research Record
Despite its contribution to climate change, holiday travel has received less attention in research than daily travel. Research has revealed that individuals residing in dense and large settlements tend to travel more frequently and over longer distances. Whether this is attributable to compensation for shortcomings of dense cities or a reflection of lifestyle is still inconclusive, yet important to uncover for formulating mitigation strategies for the environmental impact. To advance this discussion, we analyze the 2019 Norwegian holiday travel survey to determine to what extent settlement size and regional density in Norway are associated with different holiday types that reflect different lifestyles and motivations. Using negative binomial and logistic regression while controlling for socioeconomic factors, we find that (1) it is not settlement size that influences the number of holiday trips, but whether a settlement lies in a dense county; (2) making nature getaways in Scandinavia and intercontinental trips are both positively associated with county density; (3) making city trips does not show a consistent link with spatial characteristics; (4) Mediterranean seaside holidays are typical for all Norwegians, no matter the place of residence. Our results indicate compensatory motivation behind nature getaways. However, dense everyday surroundings are not detrimental to visiting other densely populated areas on city vacations. The increased likelihood of intercontinental trips among people in dense areas may be explained by lifestyle and cosmopolitan attitudes rather than being a result of compensation.
Demand responsive transit simulation of Wayne County, Michigan
Kagho, Grace Orowo; Hensle, David; Balać, Miloš; et al. (2021)
Transportation Research Record
Demand responsive transit (DRT) can provide an alternative to private cars and complement existing public transport services. However, the successful implementation of DRT services remains a challenge as both researchers and policy makers can struggle to determine what sorts of places or cities are suitable for it. Research into car-dependent cities with poor transit accessibility is sparse. This study addresses this problem, investigating the potential of DRT service in Wayne County, U.S.A., whose dominant travel mode is private car. Using an agent-based approach, DRT is simulated as a new mobility option for this region, thereby providing insights into its impact on operational, user, and system-level performance indicators. DRT scenarios are tested for different fleet sizes, vehicle occupancy, and cost policies. The results show that a DRT service in Wayne County has a certain potential, especially to increase the mobility of lower-income individuals. However, introducing the service may slightly increase the overall vehicle kilometers traveled. Specific changes in service characteristics, like service area, pricing structure, or preemptive relocation of vehicles, might be needed to fully realize the potential of pooling riders in the proposed DRT service. The authors hope that this study serves as a starting point for understanding the impacts and potential benefits of DRT in Wayne County and similar low-density and car-dependent urban areas, as well as the service parameters needed for its successful implementation.
Meaningful Modeling of Section Bus Running Times by Time Varying Mixture Distributions of Fixed Components
Büchel, Beda; Corman, Francesco (2020)
Transportation Research Record
Understanding the variability of bus travel time is a key issue in the optimization of schedules, transit reliability, route choice analysis, and transit simulation. The statistical modeling of bus travel time data is of increasing importance given the increasing availability of data. In this paper, we introduce a novel approach to modeling the day-to-day variability of urban bus running times on a section level. First, the explanatory power of conventionally used distributions is examined, based on likelihood and effect size. We show that a mixture model is a powerful tool to increase fitting performance, but the applied components need to be justified. To overcome this issue, we propose a novel model consisting of two individual characteristic distributions representing either off-peak or peak hour dynamics. The observed running time distribution at every hour of the day can be described as a combination (mixture) of the two dynamics. The proposed time varying model uses a small set of parameters, which are physically interpretable and capable of accurately describing running time distributions. With our modeling approach, we reduce the complexity of mixture models and increase the explanatory power and fit compared with conventional models.
Introducing Electrified Vehicle Dynamics in Traffic Simulation
He, Yinglong; Makridis, Michail; Mattas, Konstantinos; et al. (2020)
Transportation Research Record
Many studies have highlighted the added value of incorporating vehicle dynamics into microsimulation. Such models usually focus on simulation of conventional vehicles, failing to account for the acceleration dynamics of electrified vehicles that have different power characteristics from those of internal combustion engine vehicles (ICEV). In addition, none of them have explicitly dealt with the vehicle's deceleration characteristics. Although it is not commonly considered critical how a vehicle decelerates, unrealistic behaviors in simulations can distort both traffic flow and emissions results. The present work builds on the lightweight microsimulation free-flow acceleration (MFC) model and proposes an extension, marking the first attempt to address these research gaps. First, a comprehensive review of dynamics-based car-following (including free-flow) models is conducted. Second, the methodology of the MFC model to capture the dynamics of electrified vehicles is described. Then, the experimental setup in different dimensions is introduced for the model validation and implementation. Finally, the results of this study indicate that: (1) the acceleration and deceleration potential curves underlying the MFC model can accurately represent real dynamics of electrified vehicles tested on the chassis dynamometer; (2) smooth transitions can be guaranteed after implementing the MFC model in microsimulation; (3) when reproducing the on-road driving trajectories, the MFC model can deliver significant reductions in root mean square error (RMSE) of speed (by similar to 69%) and acceleration (by similar to 50%) compared with benchmarks; (4) the MFC model can accurately predict the vehicle 0-100 km/h acceleration specifications, with RMSE 49.4% and 56.8% lower than those of the Gipps model and the intelligent driver model (IDM), respectively.
Exploring variation properties of time use behavior on the basis of a multilevel multiple discrete-continuous extreme value model
Chikaraishi, Makoto; Zhang, Junyi; Fujiwara, Akimasa; et al. (2010)
Transportation Research Record
Demonstrative Case of a Pedestrian Network Design Model Considering Effects on Motorized Traffic
Iliopoulou, Christina; Tseliou, Maria; Kepaptsoglou, Konstantinos; et al. (2020)
Transportation Research Record
The transformation of urban roadways into pedestrian streets is a popular measure for reshaping city parts and enhancing their livability. Nevertheless, pedestrianization schemes are expected to have some impact on the performance of the neighboring road network, especially if these are established ad-hoc or solely based on non-transport criteria. This study introduces a methodological tool for supporting decisions on implementing pedestrianization schemes in urban networks. A bi-level network design model variant is developed for that purpose, whose design objective is to maximize the extent of pedestrian streets in an urban network, while maintaining acceptable impacts to the performance of the road network. Alternative decisions on pedestrianization are considered for each network segment; these include partial (one-directional) or complete (bi-directional) pedestrianization under physical and operational criteria and constraints. The model is applied for a mid-sized urban network in Greece and solved using a genetic algorithm. Results show that the pedestrianization of almost 7% of the road network in relation to length leads to a 40% increase in total network travel time, while a higher ratio of complete versus partial pedestrianization is more advantageous. Outcomes also reveal that that rigid design guidelines should be examined in a case-by-case approach, as superior results may be attained if some constraints, such as those related to the overall street width, are relaxed. Reasonably, policy priorities significantly impact generated solutions and are expected to play a decisive role in the design of pedestrianization schemes.
Transit Orientation: More Than Just Coverage—A New Method for the Assessment of Transit and Development Co-Location
Marti, Christian M.; Bertolini, Luca; Weidmann, Ulrich (2018)
Transportation Research Record

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Journal: Transportation Research Record

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