Vol 16 No 3 (2016)
2016-06-01
Vol 16 No 3 (2016)
2016-06-01
Articles
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Intermodal freight transport has been discussed for decades as an alternative to unimodal road transport. However, it still does not represent a significant portion of the total freight market. A new and promising possibility to improve the performance of freight systems is the synchromodal design of hinterland transport systems. A cornerstone for synchromodality is an integrated view in the design and operation of intermodal transport. A main benefit of this integrated view is an improved flexibility in mode choice in hinterland transport. This paper gives a detailed description of this integrated view for synchromodal freight transport. Based on this description, a mathematical model for designing service schedules for synchromodal freight transport systems is also presented. The benefits of providing integrated transport services compared to separately planned transport services are also discussed for a case in the hinterland network of the Port of Rotterdam.
Intermodal freight transport has been discussed for decades as an alternative to unimodal road transport. However, it still does not represent a significant portion of the total freight market. A new and promising possibility to improve the performance of freight systems is the synchromodal design of hinterland transport systems. A cornerstone for synchromodality is an integrated view in the design and operation of intermodal transport. A main benefit of this integrated view is an improved flexibility in mode choice in hinterland transport. This paper gives a detailed description of this integrated view for synchromodal freight transport. Based on this description, a mathematical model for designing service schedules for synchromodal freight transport systems is also presented. The benefits of providing integrated transport services compared to separately planned transport services are also discussed for a case in the hinterland network of the Port of Rotterdam.
Intermodal freight transport has been discussed for decades as an alternative to unimodal road transport. However, it still does not represent a significant portion of the total freight market. A new and promising possibility to improve the performance of freight systems is the synchromodal...
Behzad Behdani, Yun Fan, Bart Wiegmans, Rob Zuidwijk -
The road sector consumes large amounts of materials and energy and produces large quantities of greenhouse gas emissions, which can be reduced with correct information in the early planning stages of road project. An important aspect in the early planning stages is the choice between alternative road corridors that will determine the route distance and the subsequent need for different road infrastructure elements, such as bridges and tunnels. Together, these factors may heavily influence the life cycle environmental impacts of the road project. This paper presents a case study for two prospective road corridor alternatives for the Oslo fjord crossing in Norway and utilizes in a streamlined model based on life cycle assessment principles to quantify cumulative energy demand and greenhouse gas emissions for each route. This technique can be used to determine potential environmental impacts of road projects by overcoming several challenges in the early planning stages, such as the limited availability of detailed life cycle inventory data on the consumption of material and energy inputs, large uncertainty in the design and demand for road infrastructure elements, as well as in future traffic and future vehicle technologies. The results show the importance of assessing different life cycle activities, input materials, fuels and the critical components of such a system. For the Oslo fjord case, traffic during operation contributes about 94 % and 89 % of the annual CED and about 98 % and 92 % of the annual GHG emissions, for a tunnel and a bridge fjord crossing alternative respectively.
The road sector consumes large amounts of materials and energy and produces large quantities of greenhouse gas emissions, which can be reduced with correct information in the early planning stages of road project. An important aspect in the early planning stages is the choice between alternative road corridors that will determine the route distance and the subsequent need for different road infrastructure elements, such as bridges and tunnels. Together, these factors may heavily influence the life cycle environmental impacts of the road project. This paper presents a case study for two prospective road corridor alternatives for the Oslo fjord crossing in Norway and utilizes in a streamlined model based on life cycle assessment principles to quantify cumulative energy demand and greenhouse gas emissions for each route. This technique can be used to determine potential environmental impacts of road projects by overcoming several challenges in the early planning stages, such as the...
The road sector consumes large amounts of materials and energy and produces large quantities of greenhouse gas emissions, which can be reduced with correct information in the early planning stages of road project. An important aspect in the early planning stages is the choice between...
Reyn O’Born, Helge Brattebø, Ole Magnus Kålas Iversen, Sofiia Miliutenko, José Potting -
Timetable-based simulation method for choice set generation in large-scale public transport networks
The composition and size of the choice sets are a key for the correct estimation of and prediction by route choice models. While existing literature has posed a great deal of attention towards the generation of path choice sets for private transport problems, the same does not apply to public transport problems. This study proposes a timetable-based simulation method for generating path choice sets in a multimodal public transport network. Moreover, this study illustrates the feasibility of its implementation by applying the method to reproduce 5131 real-life trips in the Greater Copenhagen Area and to assess the choice set quality in a complex multimodal transport network. Results illustrate the applicability of the algorithm and the relevance of the utility specification chosen for the reproduction of real-life path choices. Moreover, results show that the level of stochasticity used in choice set generation should be high in order to provide stable parameter estimates when the choice sets are used for estimation regardless of the initial parameters for choice set generation. Last, results illustrate that adding heterogeneity across travellers should be required because coverage increases significantly, a relevant result considering that models are becoming more disaggregate in nature in real-life applications.
The composition and size of the choice sets are a key for the correct estimation of and prediction by route choice models. While existing literature has posed a great deal of attention towards the generation of path choice sets for private transport problems, the same does not apply to public transport problems. This study proposes a timetable-based simulation method for generating path choice sets in a multimodal public transport network. Moreover, this study illustrates the feasibility of its implementation by applying the method to reproduce 5131 real-life trips in the Greater Copenhagen Area and to assess the choice set quality in a complex multimodal transport network. Results illustrate the applicability of the algorithm and the relevance of the utility specification chosen for the reproduction of real-life path choices. Moreover, results show that the level of stochasticity used in choice set generation should be high in order to provide stable parameter estimates when the...
The composition and size of the choice sets are a key for the correct estimation of and prediction by route choice models. While existing literature has posed a great deal of attention towards the generation of path choice sets for private transport problems, the same does not apply to public...
Thomas Kjær Rasmussen, Marie Karen Anderson, Otto Anker Nielsen, Carlo Giacomo Prato -
Many possible emergency conditions, including evacuations, negatively affect the urban transportation system by substantially increasing the travel demand and/or reducing the supplied capacity. A transportation model can be used to quantify and understand the impact of the underlying disasters and corresponding management strategies. To this end, we develop an efficient methodology suitable for simulating multimodal transportation systems affected by emergencies, based on the novel integration of an activity-based choice model with both pre-trip and en-route choices, and a macroscopic or mesoscopic dynamic network loading model. The model structure first estimates the daily equilibrium and then uses that result as a starting point to simulate the emergency situation without further iterations. Unlike previous efforts, our methodology satisfies all requirements identified from literature regarding transportation modeling for emergencies, and is sufficiently general to investigate a wide range of emergency situations and management strategies. An evacuation case study for Delft shows the feasibility of applying the methodology. Furthermore, it yields practical insights for urban evacuation planning that stem from complex system dynamics, such as important interactions among travel directions and among modes. This supports the need for a comprehensive modeling methodology such as the one we present in this paper.
Many possible emergency conditions, including evacuations, negatively affect the urban transportation system by substantially increasing the travel demand and/or reducing the supplied capacity. A transportation model can be used to quantify and understand the impact of the underlying disasters and corresponding management strategies. To this end, we develop an efficient methodology suitable for simulating multimodal transportation systems affected by emergencies, based on the novel integration of an activity-based choice model with both pre-trip and en-route choices, and a macroscopic or mesoscopic dynamic network loading model. The model structure first estimates the daily equilibrium and then uses that result as a starting point to simulate the emergency situation without further iterations. Unlike previous efforts, our methodology satisfies all requirements identified from literature regarding transportation modeling for emergencies, and is sufficiently general to investigate...
Many possible emergency conditions, including evacuations, negatively affect the urban transportation system by substantially increasing the travel demand and/or reducing the supplied capacity. A transportation model can be used to quantify and understand the impact of the underlying disasters...
Jeroen P.T. van der Gun, Adam J. Pel, Bart van Arem -