| 1. |
|
|
| 2. |
|
|
| 3. |
|
|
| 4. |
- Beser Hugosson, Muriel, et al.
(författare)
-
Accelerated introduction of ’clean’ cars in Sweden
- 2012
-
Ingår i: Cars and carbon. - Dordrecht : Springer Science+Business Media B.V.. - 9789400721234 ; , s. 247-268
-
Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- The increased focus in Sweden on greenhouse gas emissions, oil dependency and energy efficiency has lead to the implementation of different policy measures in the transport sector. In Sweden there has been a long tradition of buying large, powerful and heavy cars with high fuel consumption and CO2 emissions. The Swedish car fleet is the heaviest car fleet in all Europe. We describe and discuss effects of major measures that have been implemented to accelerate the introduction of clean cars in the Swedish car fleet. We also briefly describe a decision support tool to evaluate policies affecting the composition of the car fleet. We find that the result of the implemented measures is a high share of clean cars in new car sales and that these policies have lead to a dominance of low emission diesel cars and E85 cars in this share. We also find that the share of biogas cars is still very small and that the use of E85 fuel for E85 cars is quite price sensitive.
|
|
| 5. |
- Beser Hugosson, Muriel, et al.
(författare)
-
Evaluation of the Swedish car fleet model using recent applications
- 2016
-
Ingår i: Transport Policy. - : Elsevier. - 0967-070X .- 1879-310X. ; 49, s. 30-40
-
Tidskriftsartikel (refereegranskat)abstract
- The composition of the car fleet with respect to age, fuel consumption and fuel types plays an important role on environmental effects, oil dependency and energy consumption. In Sweden, a number of different policies have been implemented to support CO2 emission reductions. In order to evaluate effects of different policies, a model for the evolution of the Swedish car fleet was developed in 2006. The model has been used in a number of projects since then, and it is now possible to compare forecasts with actual outcomes. Such evidence is relatively rare, and we think it may be useful to share our experience in this respect.We give a brief overview of the Swedish car fleet model system. Then we describe policies that have been implemented in recent years and the evolution of the Swedish car fleet. We then focus on two projects which enable comparison with actual outcomes, and analyse the differences between forecasts and outcomes. We find that the model has weaknesses in catching car buyers' preferences of new technology. When this is not challenged too much, the model can forecast reasonably well on an aggregate level. We also find that the model is quite sensitive to assumptions on future supply. This is not so much related to the model, but to its use. Depending on the use of the forecasts - be it car sales, emissions or fuel demand - it may be necessary to use different supply scenarios to get an idea of the robustness of the forecast result.
|
|
| 6. |
- Beser Hugosson, Muriel, 1968-
(författare)
-
Issues in Estimation and Application of Long Distance Travel Demand Models
- 2003
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Forecasts of the demand for long distance travel areessential for many decisions, such as infrastructureinvestments, operators´management policies etc. Manyresearch issues are related to this field, and the purpose ofthis thesis is to contribute to some of them. Paper I Modellingchoice of flight and booking class–a study using Stated Preference and Revealed Preference data goes into theinteresting issue of modelling departure time and ticket typechoices. The data used in the estimation process were acombination of revealed preference (RP) data and statedpreference (SP) data. A model was developed to estimaterecapture and buyup to improve the SAS (Scandinavian AirlinesSystem) yield management system. Paper II Endogenoussegmentation applied to long distance business trips in Swedenis related to the possibilities of identifying market segmentsthat differ in travel behaviour. The procedure of endogenoussegmentation has been explored to identify different tastesegments in a population. The results indicate that the methodis an efficient way of identifying market segments andoutperforms the traditional manual segmentation when modelefficiency is the objective. The restrictive assumption of independent distributed randomcomponents in the logit model utility function can be relaxedby finding a suitable nesting structure. The task ofestablishing such structures, another crucial issue in traveldemand model development, is further analysed in papers IIIExploring the HEV model to improve nesting structures of modelsfor Swedish long distance private trips and paper IV Enhancingmodel structure and treatment of incomplete geocodes in SAMPERSlong distance models. In paper III a technique to identifyscale parameters for separate alternatives is used. Based onthis, different nesting structures are tested and the resultsare compared with the old mode choice model for long distancetrips in Sweden. This paper leads to paper IV, where similarnesting structures were tested on the long distance mode anddestination choice model in the SAMPERS system. Paper IV alsodeals with data problems, as the destination coding wasincomplete. A final model formulation, related to these issuesis suggested. To turn the view a bit beside the pure estimationtechniques and structures used in the estimation of differentmodels, paper V Quantifying uncertainties in the SAMPERS longdistance forecasting model system considers uncertaintiesrelated to the fact that models are estimated on a sample of apopulation. The bootstrap method, a computer intensivestatistical method, can be used to compute statistical measuresfor very complex systems, without being bound to an analyticalapproach. The bootstrap method is applied on the SAMPERSsystem, and numerical results are presented on different modelsystem output levels.
|
|
| 7. |
|
|
| 8. |
- Beser Hugosson, Muriel
(författare)
-
Quantifying uncertainties in a national forecasting model
- 2005
-
Ingår i: Transportation Research Part A. - : Elsevier BV. - 0965-8564 .- 1879-2375. ; 39:6, s. 531-547
-
Tidskriftsartikel (refereegranskat)abstract
- Uncertainties related to demand model system outputs is an important issue in travel demand models. This paper focuses on uncertainties arisen from the fact that models are estimated on a sample of the population (and not the whole population). Forecasting systems can be quite complex, and may contain procedures that not easily permit analytically derived statistical measures of uncertainty. In this paper, the possibilities to use computer-intensive numerical methods to compute statistical measures for very complex systems, without being bound to an analytical approach, are explored. Here, the bootstrap method is used to obtain statistical measures of outputs produced by the forecasting system SAMPERS. The SAMPERS system is used by Swedish transport authorities. The bootstrap method is briefly described as well as the procedure of applying bootstrap on the SAMPERS system. Numerical results are presented for selected forecast results at different levels such as total traffic demand, origin-destination demand, train line demand and the demand on specific links. Also, the uncertainty related to the value of time estimate is analysed.
|
|
| 9. |
|
|
| 10. |
- Beser Hugosson, Muriel, et al.
(författare)
-
The Stockholm congestion charging system : an overview of the effects after six months
- 2006
-
Ingår i: Proceedings of European Transport Conference 2006.
-
Konferensbidrag (refereegranskat)abstract
- The Expert Group consists of eight traffic experts with various specialities. The group read all documentation and then, during three intensive full-day seminars, drew the conclusions presented in this summary of the evaluation of the Stockholm Trial. Several group members have in different ways participated in preparatory tasks prior to the evaluation and also conducted follow-up activities during the course of the trial.The Expert Group is chaired by Dr Jonas Eliasson, Transek AB and its secretary is Dr Lena Smidfeldt Rosqvist, Trivector Traffic AB. Other members are Associate Prof. Staffan Algers, Royal Institute of Technology/Transek, Dr Karin Brundell-Freij Engineering Faculty, Lund University, Managing Director of Inregia AB Cecilia Henriksson, Inregia AB, Prof. Lars Hultkrantz, Örebro University and scientific advisor to the Swedish Road and Transport Research Institute., Managing Director of Trivector Traffic AB Christer Ljungberg and Dr Lena Nerhagen, Swedish National Road and Transport Research Institute
|
|
