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  • 101.
    Bastian, Anne
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport planning, economics and engineering.
    Peak Car in Sweden?2015Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    It has long been well-known that economic variables such as GDP and fuel price as well as socio-demographic characteristics and spatial distribution are key factors in explaining car use trends. However, due to the recently observed plateau of total car travel in many high income countries, it has been argued that other factors, such as changes in preferences, attitudes and life-styles, have become more important drivers of car use. 

     

    This thesis shows that the two variables GDP per capita and fuel price explain most of the aggregate trends in car distances driven per adult in Sweden: as much as 80% over the years 2002 to 2012. The estimated elasticities are well in line with previous literature and can reasonably well reproduce the trend in car distances driven per adult back to 1980. We find, however, a substantial variation in elasticities between municipalities depending on public transport supply, population density, share of foreign-born inhabitants and the average income level.

     

    Swedish National Travel Survey data from 1978 to 2011 reveals that reductions in per adult driving mainly occurred among urban men. Urban men of all income groups reduced their driving for both commuting and non-commuting trips in conjunction with rising gasoline prices, which may have contributed to this development. We find that driving among those socio-demographic groups, who have better opportunities to reduce their driving, and driving for discretionary rather than commute purposes is being reduced over time. Sweden is ranked among the most gender-equal countries in the world; yet we find a substantial remaining gender gap in the share of adults driving a car on an average day, even when controlling for other socio-economic differences.

     

  • 102.
    Bastian, Anne
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport Planning, Economics and Engineering.
    Börjesson, M.
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, System Analysis and Economics.
    Eliasson, Jonas
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport Planning, Economics and Engineering.
    Response to Wadud and Baierl: “Explaining ‘peak car’ with economic variables: An observation”2017In: Transportation Research Part A: Policy and Practice, ISSN 0965-8564, E-ISSN 1879-2375, Vol. 95, p. 386-389Article in journal (Refereed)
  • 103.
    Bastian, Anne
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport planning, economics and engineering.
    Börjesson, Maria
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport planning, economics and engineering.
    Peak Car? Drivers of  the recent decline in Swedish car use2014Conference paper (Refereed)
    Abstract [en]

    It has long been well-known that economic variables such as GDP and fuel price as well as socio-demographic characteristics and spatial distribution are key factors explaining car use trends. However, due to the recently observed plateau of total car travel in many high income countries, it has been argued that other factors, such as changes in preferences, attitudes and life-styles, have become more important drivers of car use.  This paper shows that the two variables GDP per capita and fuel price explain most of the aggregate trends in car distances driven per adult in Sweden: as much as 80% over the years 2002 to 2012. The estimated elasticities are well in line with previous literature and can reasonably well reproduce the trend in car distances driven per adult back to 1980. We find, however, a substantial variation in elasticities between municipalities depending on public transport supply, population density, share of foreign-born inhabitants and the average income level.

  • 104.
    Bastian, Anne
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport planning, economics and engineering.
    Börjesson, Maria
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport planning, economics and engineering.
    Peak car?: Drivers of the recent decline in Swedish car use2015In: Transport Policy, ISSN 0967-070X, E-ISSN 1879-310X, Vol. 42, p. 94-102Article in journal (Refereed)
    Abstract [en]

    It has long been well-known that economic variables such as GDP and fuel price as well as socio-demographic characteristics and spatial distribution are key factors explaining car use trends. However, due. to the recently observed plateau of total car travel in many high income countries, it has been argued that other factors, such as changes in preferences, attitudes and life-styles, have become more important drivers of car use. This paper shows that the two variables, GDP per capita and fuel price, explain most of the aggregate trends in car distances driven per adult in Sweden: as much as 80% over the years 2002 to 2012. The estimated elasticities are well in line with previous literature and can reasonably well reproduce the trend in car distances driven per adult back to 1980. We find, however, a substantial variation in elasticities between municipalities depending on public transport supply, population density, share of foreign-born inhabitants and the average income level.

  • 105.
    Bastian, Anne
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Transport Science.
    Börjesson, Maria
    KTH, School of Architecture and the Built Environment (ABE), Centres, Centre for Transport Studies, CTS.
    The city as a driver of new mobility patterns, cycling and gender equality: Travel behaviour trends in Stockholm 1985-2015Manuscript (preprint) (Other academic)
    Abstract [en]

    We analyse changes in individual travel behaviour in Stockholm County over 30 years, using three large cross-sectional travel survey data sets. We show how travel patterns evolve over time by gender, income and age-group, in different areas of the region (centre vs. periphery).  We relate the observed trends in travel behaviour to societal trends (gender equality, ICT adoption, knowledge-based economy) and policy changes (congestion charges), and we compare them to trends in other European capital cities.

  • 106.
    Bastian, Anne
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport Planning, Economics and Engineering. KTH, School of Architecture and the Built Environment (ABE), Centres, Centre for Transport Studies, CTS.
    Börjesson, Maria
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport Planning, Economics and Engineering. KTH, School of Architecture and the Built Environment (ABE), Centres, Centre for Transport Studies, CTS.
    Eliasson, Jonas
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport Planning, Economics and Engineering. KTH, School of Architecture and the Built Environment (ABE), Centres, Centre for Transport Studies, CTS.
    Explaining “peak car” with economic variables2016In: Transportation Research Part A: Policy and Practice, ISSN 0965-8564, E-ISSN 1879-2375, Vol. 2016, no 88, p. 236-250Article in journal (Refereed)
    Abstract [en]

    Many western countries have seen a plateau and subsequent decrease of car travel during the 21st century. What has generated particular interest and debate is the statement that the development cannot be explained by changes in traditional explanatory factors such as GDP and fuel prices. Instead, it has been argued, the observed trends are indications of substantial changes in lifestyles, preferences and attitudes to car travel; what we are experiencing is not just a temporary plateau, but a true “peak car”. However, this study shows that the traditional variables GDP and fuel price are in fact sufficient to explain the observed trends in car traffic in all the countries included in our study: the United States, France, the United Kingdom, Sweden and (to a large extent) Australia and Germany. We argue that the importance of the fuel price increases in the early 2000s has been underappreciated in the studies that shaped the later debate. Results also indicate that GDP elasticities tend to decrease with rising GDP, and that fuel price elasticities tend to increase at high price levels and during periods of rapid price increases.

  • 107.
    Bastian, Anne
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport planning, economics and engineering.
    Maria, Börjesson
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport planning, economics and engineering.
    Peak Car for urban Swedish men?2014In: Proceedings of Symposium of the European Association for Research in Transportation (hEART),September 10, 2014 – September 12, 2014, Leeds, UK, 2014Conference paper (Refereed)
    Abstract [en]

    We study long-term trends in regional car travel demand within and across socio-demographic groups in Sweden, using cross-sectional data from National Travel Surveys, spanning the period from 1978 to 2011. We find that the reduction in per-adult driving in Sweden mainly occurs among urban men. Urban men of all income groups reduced their driving for both commuting and non-commuting trips in conjunction with rising gasoline prices, which may have contributed to this development. We find that driving among those socio-demographic groups, who have better opportunities to reduce their driving, and driving for discretionary rather than commute purposes is being reduced over time. Sweden is ranked among the most gender-equal countries in the world; yet we find a substantial remaining gender gap in the share of adults driving a car on an average day, even when controlling for other socio-economic differences.

     

  • 108. Bayazit, Mehmet
    et al.
    Das, Prabir Kumar
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Highway and Railway Engineering.
    Tasdemir, Yuksel y
    Moisture susceptibility of warm mix asphalt2014In: Indian journal of engineering & materials sciences, ISSN 0971-4588, E-ISSN 0975-1017, Vol. 21, no 6, p. 683-691Article in journal (Refereed)
    Abstract [en]

    In this study, moisture susceptibility characteristics of wax modified bitumens and warm mix asphalt (WMA) mixtures are determined. The asphalt mixtures are prepared with 50170 penetration grade unmodified bitumen and modified bitumens with three different types of additives (Fischer Tropsch wax, montan wax and polyethylene wax) by weight of 6%. The moisture susceptibility characteristic of the four bitumens is determined with Sessile drop method and that for asphalt mixtures is determined with Nicholson stripping test on loose asphalt mixtures and Modified Lottman test on compacted asphalt mixtures. Furthermore, Marshall stability with different blow numbers of WMA mixtures are determined. The findings from all of these tests suggest that due to the Fischer Tropsch wax and montan wax modification the asphalt mixture become more moisture susceptible which correlates with the surface energy characterization. Interestingly, polyethylene wax modification shows positive moisture performance.

  • 109.
    Bayley, Michael
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Traffic and Logistics.
    Regional development via high-speed rail: A study of the Stockholm-Mälaren region and possibilities for Melbourne-regional Victoria2012Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The purpose of this thesis is to examine, based on a study of the regional high-speed corridors in the Stockholm-Mälaren Region, the possibilities for regional high-speed rail in Melbourne-regional Victoria (Australia) to improve accessibility, and achieve regional development and balanced growth between the capital and its surrounding regions. It deals with the concept of 'regional' high-speed rail, a variant of classic high-speed rail that serves centres along regional corridors stemming from a large city and whose travel purpose includes a high share of daily commuting and occasional business and leisure travel with journey times of up to two hours.

    The literature review reveals an emerging market for regional high-speed rail, which also has the potential to stimulate regional development and give rise to a complementary polycentric structure, subject to appropriate supporting conditions. The link between high-speed rail and regional development is based on the assumption that increased accessibility expands labour markets and offers people and firms wider location choices by permitting longer commuting.

    The Stockholm-Mälaren region analysis includes a review of the past-studied Svealand line, a comparative study of city groups and case studies. Key outcomes are summarised as follows:

    • Regional centres have in general strongly benefited from a high-speed rail connection, a finding supported by steadily increasing commuting, and population and job growth.

    • Cities within one hour of Stockholm experienced the greatest increase in commuting that was matched by consistently positive population and emerging job growth; these centres have benefited the most from high-speed, which reinforced ongoing activities.

    • Small-medium cities greater than one hour from Stockholm suffering population and job decline experienced recovery to neutral or positive growth with the introduction of high-speed; these centres depend on supportive strategies to fully capture its benefits, particularly those that foster inter-city exchange and the formation of city networks.

    • Supportive strategies for high-speed rail include: public transport coordination, station redevelopment, establishment of public offices and measures for inter-city exchange.

    Regional high-speed rail is proposed in Melbourne-regional Victoria based on the application of speed enhancements (to 160, 200 and 250 km/h) on existing rail corridors, which reduce travel times between Melbourne and regional centres, facilitating increased commuting and stimulating regional development. The key outcomes are summarised as follows:

    • The improvement of inner lines to 200-250 km/h and outer lines to 160 km/h achieves an efficient balance between improved accessibility and economy in the short-medium term; future enhancements include peripheral links and higher speeds on outer lines.

    • Upgrading lines to true ‘high-speed’ status requires electrification, modern signalling and track improvements, which deliver improved run times for the higher investment.

    • Estimated demand growth factors range from 1.4 to 2.0 depending on speed and route.

    • Positive regional development effects are expected if appropriate supportive strategies are applied, especially ones that support economic specialisation and city networking.

  • 110.
    Bekele, Abiy
    KTH, School of Architecture and the Built Environment (ABE), Transport Science.
    Implementation of the AASHTO pavement design procedures into MULTI-PAVE.2011Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This thesis implements the empirical pavement design procedures for flexible as well as rigid pavement by American Association of State Highways and Transportation Officials (AASHTO) into two MATLAB modules of MULTI-PAVE. MULTI-PAVE was developed as a teaching tool that performs pavement thickness design for multiple design procedures using a common input file and a common output format. The AASHTO components were developed in accordance with the 1993 AASHTO Pavement Design Guide, and verified against the original design method. The thicknesses of the Asphalt Concrete, Base Course and Sub-base Course are the design outputs for flexible pavement. For rigid pavement, the thickness of slab is determined for various types of concrete pavements. The modules will be included in a MULTI-PAVE framework to compare the design outputs with other design methods.

     

  • 111.
    Bekele, Abiy
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Materials.
    Birgisson, Björn
    KTH, School of Architecture and the Built Environment (ABE), Transport Science. KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Highway Engineering Laboratory.
    Rydén, Nils
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Materials.
    Gudmarsson, Anders
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Materials.
    Slow dynamic diagnosis of asphalt concrete specimen to determine level of damage caused by static low temperature conditioning2017In: 43rd Annual Review of Progress in Quantitative Nondestructive Evaluation, American Institute of Physics (AIP), 2017, Vol. 1806, article id 080012Conference paper (Refereed)
    Abstract [en]

    The phenomenon of slow dynamics has been observed in a variety of materials which are considered as relatively homogeneous that exhibit nonlinearity due to the presence of defects or cracks within them. Experimental realizations in previous work suggest that slow dynamics can be in response to acoustic drives with relatively larger amplitude as well as rapid change of temperature. Slow dynamics as a nonlinear elastic response of damaged materials is manifested as a sharp drop and then recovery of resonance frequency linearly with logarithmic time. In this work, slow dynamics recovery is intended to be used as a means of identifying and evaluating thermal damage on an asphalt concrete specimen. The experimental protocol for measuring slow dynamics is based on the technique of nonlinear resonance spectroscopy and is set up with non-contact excitation using a loud speaker and the data acquisition tool box of Matlab. Sweeps of frequency with low amplitude are applied in order to probe the specimen at its linear viscoelastic state. The drop and then recovery in fundamental axially symmetric resonance frequency is observed after the specimen is exposed to sudden temperature change. The investigation of the viscoelastic contribution to the change in resonance frequency and slow dynamics can help identify micro-damage in asphalt concrete samples.

  • 112.
    Belaieff, Vera
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport Planning, Economics and Engineering.
    Uttran station: En studie om hur en ny pendeltågsstation påverkar resenärerna och restiden2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Travelling is a big part of people’s everyday life. In the urban area of Stockholm, the public transport of mostly busses and various types of trains are popular and the traffic is driven by AB Storstockholms Lokaltrafik, SL. The choice between SL and other traveling types is determining by factors such as available stations and reasonable traveling time.

    SL has a method to analyse the generalised travel cost called KRESU. In this thesis, the KRESU-method and methods to analyse the availability are used and applied on the area Uttran. Uttran is located between Stockholm and Södertälje and the rail where the commuter trains passes extends right through the area. The purpose of this thesis is to study the effects on the availability and travelling times from the area of Uttran to Stockholm and Södertälje.

    The result includes the impact of the traveling time in the different directions and also how many passengers that are affected. The conclusion involves a discussion of the result and submit suggestions for further studies.

  • 113. Ben-Akiva, Moshe
    et al.
    Koutsopoulos, Haris
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Traffic and Logistics.
    Antoniou, C
    Balakrishna, R
    Traffic Simulation with DynaMIT2010In: Fundamentals of Traffic Simulation, Springer, 2010, p. 363-398Chapter in book (Refereed)
    Abstract [en]

    DynaMIT (Dynamic Network Assignment for the Management of Information to Travelers) is a dynamic traffic assignment model system that estimates and predicts traffic. DynaMIT is also a real-time system for decision support at traffic management centers for generation of predictive traffic information. A planning version also exists. DynaMIT captures the dynamic performance of the network (e.g., lane-based queuing and spillback effects), travel behavior, its sensitivity to traffic conditions and available traffic information, and consistency between demand and supply. DynaMIT consists of a demand simulator, a supply simulator, and algorithms that capture demand and supply interactions. Methodologies for the online and offline estimation of OD flows and the offline and online calibration of various inputs and parameters (such as network performance parameters) have been developed as well. Several case studies from the United States, Europe, and Asia are discussed, and a distributed version of DynaMIT is also presented.

  • 114. Ben-Akiva, Moshe
    et al.
    Koutsopoulos, Haris
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Traffic and Logistics.
    Toledo, Tomer
    Yang, Qi
    Choundhury, Charisma
    Antoniou, Constantinos
    Balakrishna, Ramachandran
    Traffic Simulation with MITSIMLab2010In: Fundamentals of Traffic Simulation, Springer, 2010, p. 233-268Chapter in book (Refereed)
    Abstract [en]

    MITSIMLab (MIcroscopic Traffic SIMulation Laboratory) is a microscopic traffic simulation model that evaluates the impacts of alternative traffic management system designs at the operational level and assists in their subsequent refinement. MITSIMLab models the travel and driving behavior of individual vehicles, the detailed movement of transit vehicles, and the various control and information provision strategies through a generic controller. A calibration methodology for important parameters and inputs was also developed. The model has been extended to address the special driving behavior evidenced in urban networks and has been used as a test bed for the evaluation of advanced traveler information systems (ATIS). Calibration and validation results from networks in the United States and Europe are discussed.

  • 115. Bergh, Torsten
    et al.
    Nordqvist, Karin
    Stromgren, Per
    Davidsson, Fredrik
    Bång, Karl
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport Planning, Economics and Engineering.
    Carlsson, Arne
    Capacity issues in Sweden - applications and research2016In: INTERNATIONAL SYMPOSIUM ON ENHANCING HIGHWAY PERFORMANCE (ISEHP), (7TH INTERNATIONAL SYMPOSIUM ON HIGHWAY CAPACITY AND QUALITY OF SERVICE, 3RD INTERNATIONAL SYMPOSIUM ON FREEWAY AND TOLLWAY OPERATIONS), Elsevier, 2016, 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).

  • 116.
    Bergholm, Fredrik
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Highway and Railway Engineering.
    Francisco, A
    On the importance of being asymmetric in stereopsis - or the use of skewed parallel cameras1998In: Int. J. of Computer Vision, Vol. 29, no 3Article in journal (Refereed)
  • 117.
    Berglund, Svante
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport planning, economics and engineering.
    Canella, Olivier
    Engelsson, Leonid
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport planning, economics and engineering.
    Flötteröd, Gunnar
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport planning, economics and engineering.
    Jonsson, Daniel
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport planning, economics and engineering.
    Kristoffersson, Ida
    West, Jens
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport planning, economics and engineering. SWECO, Sweden.
    Integration of dynamic traffic assignment with a travel demand model for the Stockholm region2014Conference paper (Other academic)
  • 118.
    Bergman, Klara
    KTH, School of Architecture and the Built Environment (ABE), Transport Science.
    Tunnelsäkerhet: En inventering av olyckor i fyra vägtunnlar i Stockholm2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Tunnel safety – an inventory of accidents in four road tunnels in Stockholm

    This report investigates traffic accidents in four road tunnels in Stockholm. The tunnels investigated are Klaratunneln, Söderledstunneln, Törnskogstunneln and Häggvikstunneln. The main purpose of this project was to work with a delimited part of the project TUFS (Tunnel Framkomlighet och Säkerhet, Tunnel practicability and safety, my translation) that is going to build a knowledge bank for Swedish road tunnel accidents. The goal of this project was to investigate if the forecasts for accident rates in the tunnels calculated from empirical data differ from the forecasts of the road network made by the forecast program used by Trafikverket, Lill-EVA, for the observed tunnels. Another goal was to determine where accidents occur in the tunnels. In addition, two different tunnel types were compared in terms of accident rates. The tunnel types are located in: countryside (high speed, low traffic flows, no on- and off ramps) or urban center (low speed, high traffic flows, on- and off ramps). Accident data has been collected from the data bases STRADA and NTS and compiled in histograms displaying accident type, light conditions, the seriousness of the accident and number of accidents/year.

    The results showed that there are no differences in accident rates calculated by Lill-EVA and empirical data for accident rate, serious accident rate and death rate. However, there was a difference in the results concerning light injuries. No difference was found regarding the two tunnel types.

    Rear-end collision was the most common accident type in Söderledstunneln and serial vehicle crashes in Törnskogstunneln and Häggvikstunneln. Vehicles that got stuck in the tunnel entrance dominated the accident type in Klaratunneln. The majority of the accidents occurred in daylight.

    The coordinate positions for the accidents showed that there was a concentration of accidents near the tunnel entrance in Klaratunneln, Söderledstunneln and Häggvikstunneln. This is not the case for Törnskogstunneln where accidents have occurred in the tunnel center.

  • 119.
    Bergman, Klara
    KTH, School of Architecture and the Built Environment (ABE), Transport Science.
    Understanding the relationship between property development and Bus Rapid Transit: A spatiotemporal analysis of transit oriented development in Curitiba, Brazil2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The city of Curitiba in southern Brazil is considered to be the cradle of the Bus Rapid Transit

    (BRT) system. Curitiba has a population of around 1.9 million people and has a higher

    development index than Brazil in general. A master plan approved in the middle of the 1960’s

    has guided development of the city in a Transit Oriented Development (TOD) direction by

    zoning for high development densities close to the five BRT trunk lines in so-called structural

    axes. This thesis aimed at performing a spatiotemporal and statistical analysis of property

    development in Curitiba, to examine if the BRT system could have been a motivator for

    property development, and if so, to what extent. Spatial data including for instance a database

    of building permits, population densities, social housing locations and cost of land were used

    in the analysis. The analysis was divided into three themes to examine property development

    from three perspectives; Timing of Development, Density of Development and Social Housing

    Inclusion. Results for the entire BRT system showed that a greater “time lag” of property

    development following BRT development also meant that the property in question was located

    further away from a BRT line, suggesting that areas close to the BRT were popular. The

    individual lines showed different effects of timing of development, relating to the heterogenic

    surroundings and the characteristics of the time periods when the BRT was implemented. High

    development densities are found in the structural corridors, but high population densities are

    not only found there but also in areas in the South and Southwest parts of Curitiba. These areas

    coincide with areas of social housing, which historically has been planned in areas not served

    by the trunk lines of the BRT system. The conclusion of the thesis is that the BRT system

    certainly has been a motivator for property development, and that TOD planning with

    thoughtful zoning can be a powerful tool to direct property development. In order to counteract

    urban segregation, strategies for including social housing in the structural axes must

    be

    implemented.

  • 120.
    Beser Hugosson, Muriel
    KTH, School of Architecture and the Built Environment (ABE), Centres, Centre for Transport Studies, CTS. KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport and Location Analysis.
    Quantifying uncertainties in a national forecasting model2005In: Transportation Research Part A: Policy and Practice, ISSN 0965-8564, E-ISSN 1879-2375, Vol. 39, no 6, p. 531-547Article in journal (Refereed)
    Abstract [en]

    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. 

  • 121.
    Beser Hugosson, Muriel
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport and Location Analysis. KTH, School of Architecture and the Built Environment (ABE), Centres, Centre for Transport Studies, CTS.
    Algers, Staffan
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport and Location Analysis. KTH, School of Architecture and the Built Environment (ABE), Centres, Centre for Transport Studies, CTS.
    Accelerated Introduction of "Clean" Cars in Sweden2011Report (Other academic)
  • 122.
    Beser Hugosson, Muriel
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport and Location Analysis. KTH, School of Architecture and the Built Environment (ABE), Centres, Centre for Transport Studies, CTS.
    Algers, Staffan
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport and Location Analysis. KTH, School of Architecture and the Built Environment (ABE), Centres, Centre for Transport Studies, CTS.
    Accelerated introduction of ’clean’ cars in Sweden2012In: Cars and carbon: Automobiles and European climate policy in a global context, Springer Science+Business Media B.V. , 2012, p. 247-268Chapter in book (Other academic)
    Abstract [en]

    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 CO<inf>2</inf> 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.

  • 123.
    Beser Hugosson, Muriel
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Centres, Centre for Transport Studies, CTS. KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport and Location Analysis.
    Algers, Staffan
    KTH, School of Architecture and the Built Environment (ABE), Centres, Centre for Transport Studies, CTS. KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport and Location Analysis.
    SAMPERS - The new Swedish National Travel Demand Forecasting Tool2002In: National Transport Models - Recent Developments and Prospects, Advances in Spatial Science, Berlin: Springer-Verlag , 2002Chapter in book (Refereed)
  • 124.
    Beser Hugosson, Muriel
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, System Analysis and Economics.
    Algers, Staffan
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport Planning, Economics and Engineering.
    Habibi, Shiva
    KTH, School of Architecture and the Built Environment (ABE), Transport Science.
    Sundbergh, P.
    Evaluation of the Swedish car fleet model using recent applications2016In: Transport Policy, ISSN 0967-070X, E-ISSN 1879-310X, Vol. 49, p. 30-40Article in journal (Refereed)
    Abstract [en]

    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.

  • 125.
    Beser Hugosson, Muriel
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Transport Science. KTH, School of Architecture and the Built Environment (ABE), Centres, Centre for Transport Studies, CTS.
    Algers, Staffan
    KTH, School of Architecture and the Built Environment (ABE), Transport Science.
    Habibi, Shiva
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, System Analysis and Economics.
    Sundbergh, Pia
    The Swedish Car Fleet Model: Evaluation of Recent ApplicationsManuscript (preprint) (Other academic)
  • 126.
    Beser Hugosson, Muriel
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Centres, Centre for Transport Studies, CTS. KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport and Location Analysis.
    Eliasson, Jonas
    KTH, School of Architecture and the Built Environment (ABE), Centres, Centre for Transport Studies, CTS.
    Karlström, Anders
    KTH, School of Architecture and the Built Environment (ABE), Centres, Centre for Transport Studies, CTS. KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport and Location Analysis.
    Mattsson, Lars-Göran
    KTH, School of Architecture and the Built Environment (ABE), Centres, Centre for Transport Studies, CTS. KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport and Location Analysis.
    Rosenlind, Stina
    Kan vi lita på trafikprognoser? – En kritisk granskning av några trafikmodeller1996Report (Other academic)
  • 127.
    Birgisson, Bjorn
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Highway and Railway Engineering.
    Beatty, C.L.
    Nanomodified Concrete Additive and High Performance Cement Past and Concrete Therefrom2006Patent (Other (popular science, discussion, etc.))
  • 128.
    Birgisson, Björn
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Highway and Railway Engineering.
    Dham, M.
    Optimization of Clay Addition for Enhancement of Pozzolanic Reaction in Nanomodified Cement Paste2011In: Nanotechnology in Civil Infrastructure: A Paradigm Shift / [ed] Kasthurirangan Gopalakrishnan, Bjorn Birgisson, Peter Taylor, Nii O. Attoh-Okine, Springer Berlin/Heidelberg, 2011Chapter in book (Refereed)
  • 129.
    Birgisson, Björn
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Highway and Railway Engineering.
    Montepara, A.
    Romeo, E.
    Tebaldi, G.
    Characterization of Asphalt Mixture Cracking Behavior using the Three-Point Bending Beam Test2011In: The international journal of pavement engineering, ISSN 1029-8436, E-ISSN 1477-268X, Vol. 12, no 6Article in journal (Refereed)
  • 130.
    Birgisson, Björn
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Highway and Railway Engineering.
    Montepara, Antonio
    Department of Civil and Environmental Engineering and Architecture, University of Parma.
    Romeo, Elena
    Department of Civil and Environmental Engineering and Architecture, University of Parma.
    Tebaldi, Gabriele
    Department of Civil and Environmental Engineering and Architecture, University of Parma.
    Characterisation of asphalt mixture cracking behaviour using the three-point bending beam test2011In: The international journal of pavement engineering, ISSN 1029-8436, E-ISSN 1477-268X, Vol. 12, no 6, p. 569-578Article in journal (Refereed)
    Abstract [en]

    The use of a three-point bending beam (3PB) test was investigated to characterise hot mix asphalt (HMA) cracking behaviour. Fundamental HMA fracture properties, identified as tensile strength and fracture energy density at first fracture, were determined for six different asphalt mixtures (two natural and four SBS polymer modified) applying the HMA Fracture Mechanics framework. Full-field strain maps obtained from an in-house developed digital image correlation-based method were observed to better understand the crack initiation and propagation mechanisms in the 3PB specimen. The resulting fracture behaviour was predicted using a displacement discontinuity boundary element method to model the microstructure of the six asphalt mixtures and to predict their fracture properties. Both numerical and experimental results indicate that the fracture mechanism of asphalt mixtures can be properly described from 3PB test results when appropriate interpretation models are used.

  • 131.
    Birgisson, Björn
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Highway and Railway Engineering.
    Ovik, J
    Newcomb, David
    Predictions of Seasonal Variations in Flexible Pavements at the MN/ROAD Site2002In: Transportation Research Record, Vol. 1730Article in journal (Refereed)
  • 132.
    Birgisson, Björn
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Highway and Railway Engineering.
    Roberson, R
    Drainage of Pavement Material: Design and Construction Issues2000In: Transportation Research Record, Vol. 1709Article in journal (Refereed)
  • 133.
    Birgisson, Björn
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Highway and Railway Engineering.
    Roque, R
    Page, G
    Evaluation of Water Damage Using Hot Mix Asphalt Fracture Mechanics2003In: Journal of Asphalt Paving Technologists, Vol. 72Article in journal (Refereed)
  • 134.
    Birgisson, Björn
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Highway and Railway Engineering.
    Roque, R
    Page, G
    Ultrasonic Pulse Wave Velocity Test as a Tool for Monitoring Changes in HMA Mixture Integrity due to Exposure to Moisture2003In: Transportation Research Record, Vol. 1832Article in journal (Refereed)
  • 135.
    Birgisson, Björn
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Highway and Railway Engineering.
    Ruth, B
    Development of Tentative Guidelines for the Selection of Aggregate Gra¬dations in Hot-Mix Asphalt2002In: Journal of ASTM International, Vol. 1412Article in journal (Refereed)
  • 136.
    Birgisson, Björn
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Highway and Railway Engineering.
    Ruth, B
    Improved Performance by Consideration of Terrain Conditions: Soils, Drainage, and Climate2003In: Transportation Research Record, Vol. 1819Article in journal (Refereed)
  • 137.
    Birgisson, Björn
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Highway and Railway Engineering.
    Sangpetngam, B
    Roque, R
    Prediction of the Viscoelastic Response and Crack Growth in Asphalt Mixtures Using the Boundary Element Method2002In: Transportation Research Record, Vol. 1789Article in journal (Refereed)
  • 138.
    Birgisson, Björn
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Highway and Railway Engineering.
    Sjölander, Peta White
    KTH, School of Technology and Health (STH), Health Systems Engineering, Ergonomics.
    Snickars, Folke
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, Urban and Regional Studies.
    Kjellberg, Peter
    KTH.
    Perhson, Susanna
    KTH.
    Eriksson, Thomas
    KTH.
    Reitberger, Göran
    KTH.
    RAE2012: KTH Research Assessment Exercise 20122012Book (Other (popular science, discussion, etc.))
  • 139.
    Birgisson, Björn
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Highway and Railway Engineering.
    Soranakom, C
    Napier, J
    Roque, R
    Simulation of Fracture Initiation in Hot Mix Asphalt Mixtures2003In: Transportation Research Record, Vol. 1849Article in journal (Refereed)
  • 140.
    Bjurström, Henrik
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Highway and Railway Engineering.
    Air-coupled microphone measurements of guided waves in concrete plates2014Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Quality control and quality assurance of pavements is today primarily based on core samples. Air void content and pavement thickness are parameters that are evaluated. However, no parameter connected to the stiffness is evaluated. There is a need for fast and reliable test methods that are truly non-destructive in order to achieve an effective quality control and quality assurance of pavements. This licentiate thesis presents surface wave testing using air-coupled microphones as receivers. The measurements presented in this work are performed in order to move towards non-contact measurements of material stiffness. The non-contact measurements are compared to conventional accelerometer measurements in order to compare the noncontact measurements to a “reference test”. The two appended papers are focused on evaluating one parameter in each paper. In the first paper all equipment needed to perform non-contact measurements are mounted on a trolley in order to enable measurements while rolling the trolley forward. It is shown that rolling measurements can provide rapid and reliable measurements of the Rayleigh wave velocity over large areas. However, the measurements are shown to be sensitive to misalignments between the microphone array and the measured surface. An uneven surface can thus cause major errors in the calculated results. The second paper presents an alternative method to evaluate the thickness resonance frequency of a concrete plate. It is demonstrated how the established Impact Echo method can give erroneous results when aircoupled microphones are used as receivers. Instead a method based on backward wave propagation is introduced. It is demonstrated how waves with negative phase velocities can be identified in a narrow frequency span close to the thickness resonance.

  • 141.
    Bjurström, Henrik
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Highway and Railway Engineering.
    Rydén, Nils
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Highway and Railway Engineering.
    Air-coupled detection of the S1-ZGV lamb mode in a concrete plate based on backward wave propagation2013In: Review Of Progress In Quantitative Nondestructive Evaluation, Vols 32a And 32b, American Institute of Physics (AIP), 2013, p. 1294-1300Conference paper (Refereed)
    Abstract [en]

    Impact Echo is commonly used to determine thickness of concrete plate like structures. The method is based on the generation and detection of the plate thickness resonance frequency, where the group velocity of the first higher symmetric Lamb mode goes to zero (S1-ZGV). When using air-coupled microphones as receivers it is hard to determine the correct resonance frequency due to low signal to noise ratio. In this study multichannel signal processing is used to identify the S1-ZGV frequency, based on backward wave propagation instead of the conventional amplitude spectrum approach.

  • 142.
    Bjäring, Camilla
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Traffic and Logistics.
    ITS under byggtid - utvärdering med dynameq: Fallstudie: Intunnling av E4/E20 Tomteboda - Haga södra2012Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Essingeleden in Stockholm is the most heavily congested road segment in Scandinavia and it is of

    great importance for as well traffic within the city as for transit traffic. The capacity of Essingeleden

    and Norra Länken is not enough to accommodate all traffic. At times it is not moving at all, which

    results in long queues and an augmented risk of accidents. Consequently measures for increasing the

    capacity on E4/E20, which will reduce congestion and the risk of accidents, are implemented by

    Trafikverket. In fall 2012 one lane of three at Pampas will be closed and so will the exit from

    Essingeleden to Norra Stationsgatan, called Parkeringsbron. No new connection will be in place until

    2017. This implies that if no measures are taken the congestion will be exacerbated. The purpose of

    the thesis was to study how ITS can be used to divert the traffic, with the aim of gaining an

    accessibility that is as good as possible through the construction site at Norra Station, during the time

    Parkeringsbron is closed. Thereafter an ITS

    solution was suggested and evaluated using traffic

    simulation. The problem was modelled with the mesoscopic simulation tool Dynameq, which like

    microscopic models treats congestion and queue build

    up and dissipation in a detailed way, while it

    is an equilibrium model with consistent route choices, like macroscopic models. A Dynameq network

    of Stockholm was available, but the work with coding and calibrating the model proved to be too

    extensive, why the decision was taken that focus should be on having the network behave as

    expected according to traffic flow theory and that evaluation and analysis should be done as

    comparisons between scenarios. This implies that the model does not properly represent reality and

    that the results thus not can be applied on the real scenario. Initially the cause was to evaluate

    solutions to the problem using Dynameq, but during the work process more and more of the

    software’s weaknesses were discovered, which makes it unsuitable for this type of analysis. There

    are, among others are deficiencies in modelling of lane

    ‐choice and lane‐change and in route‐

    choice

    modelling. An analysis was still performed and the result showed that large gains of travel time and

    throughput can be made when an ITS

    solution is implemented, if it is well planned and clear and

    thereby leads to a large diversion rate. This contributes to a more efficient use of the road network

    and shorter travel times for all vehicles.

  • 143. Björnsson, G
    et al.
    Erlingsson, Sigurd
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Highway and Railway Engineering.
    Sego, D
    Thaw induced bearing capacity of road materials2007In: Proceedings of the XIV European Conference on Soil Mechanics and Geotechnical Engineering, 2007, Vol. 3, p. 1613-1618Conference paper (Refereed)
  • 144.
    Blanco Munuera, Luis
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport Planning, Economics and Engineering.
    Maritime freight transportation and the impact of regulatory changes: A comparison between Spain and Sweden2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Maritime freight is a sector of high importance in the field of international trade. During the last decades, maritime freight transportation has been growing progressively, nowa- days,  in order to transport large quantities of materials and save  great distances,  it is     the most used transport system.   The maritime freight transport involves  a large num-   ber of companies, which generates a greater number of jobs and acquires an additional importance for the economy and trade of the country. However, in order to maritime transportation to be in optimal conditions, it must be accompanied by a network of infrastructures and strategic points that allow different companies to carry out their func- tions.

    Nowadays, large quantities of goods are transported through the sea, this is why a regulatory framework is needed to control the various limitations and restrictions that must be imposed at sea. The organization in charge of this work is the so-called SOLAS (Safety of Life At Sea), which is part of the United  Nations  department.  This  organi- zation is responsible, as mentioned above, for safety at sea for ships and goods, it acts according to the current situation and responding to different disasters. As a result of certain accidents, whether navigation or breakage, the last law that has implemented is known  as  Verified  Gross  Mass (VGM).

    This thesis is divided into two parts, the first one analyses the importance of maritime transport for the countries of  Spain  and  Sweden. It  will  show  the  repercussion  it has on the country and its different connections to transport the goods through the country, as well as future trends to move these goods for each country as well. To conclude this part, a comparison will be made between both countries. Secondly, a study will be car- ried out on the effect of the law that was implemented dated back on 1 July 2016, the so-called Verified Gross Mass. A study is carried out in order to assess the challenges and opportunities generated by this law for the different stakeholders involved in maritime transport and how they have been acting in the countries of Spain and Sweden. Hence, fi- nal conclusions can be obtained regarding the conduct of each stakeholder in each country.

    Finally, the importance of road transport as the large transport system will be high- lighted in combination with the maritime transportation in both countries. On the other hand, regulatory changes will make a cooperation between stakeholders in order to reduce the  impact  in  their activity.

  • 145.
    Blom Västberg, Oskar
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, System Analysis and Economics.
    Five papers on large scale dynamic discrete choice models of transportation2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Travel demand models have long been used as tools by decision makers and researchers to analyse the effects of policies and infrastructure investments. The purpose of this thesis is to develop a travel demand model which is: sensitive to policies affecting timing of trips and time-space constraints; is consistent with microeconomics; and consistently treats the joint choice of the number of trips to perform during day as well as departure time, destination and mode for all trips. This is achieved using a dynamic discrete choice model (DDCM) of travel demand. The model further allows for a joint treatment of within-day travelling and between-day activity scheduling assuming that individuals are influenced by the past and considers the future when deciding what to do on a certain day.

    Paper I develops and provides estimation techniques for the daily component of the proposed travel demand model and present simulation results provides within sample validation of the model. Paper II extends the model to allow for correlation in preferences over the course of a day using a mixed-logit specification. Paper III introduces a day-to-day connection by using an infinite horizon DDCM. To allow for estimation of the combined model, Paper III develops conditions under which sequential estimation can be used to estimate very large scale DDCM models in situations where: the discrete state variable is partly latent but transitions are observed; the model repeatedly returns to a small set of states; and between these states there is no discounting, random error terms are i.i.d Gumble and transitions in the discrete state variable is deterministic given a decision.

    Paper IV develops a dynamic discrete continuous choice model for a household deciding on the number of cars to own, their fuel type and the yearly mileage for each car. It thus contributes to bridging the gap between discrete continuous choice models and DDCMs of car ownership.

    Infinite horizon DDCMs are commonly found in the literature and are used in, e.g., Paper III and IV in this thesis. It has been well established that the discount factor must be strictly less than one for such models to be well defined.Paper V show that it is possible to extend the framework to discount factors greater than one, allowing DDCM's to describe agents that: maximize the average utility per stage (when there is no discounting); value the future greater than the present and thus prefers improving sequences of outcomes implying that they take high costs early and reach a potential terminal state sooner than optimal.

  • 146.
    Blom Västberg, Oskar
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Transport Science.
    Dong, H.
    Hu, Xiaoming
    KTH, School of Engineering Sciences (SCI), Mathematics (Dept.).
    Optimal pedestrian evacuation using Model Predictive Control2013In: 2013 European Control Conference, ECC 2013, IEEE , 2013, p. 1224-1229Conference paper (Refereed)
    Abstract [en]

    During an emergency in a building complex, an effective evacuation is essential to avoid crowd disasters. This article presents a route guiding that minimize the evacuation time during the evacuating of pedestrians from a building.

  • 147.
    Blom Västberg, Oskar
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, System Analysis and Economics. Royal Institute of Technology.
    Karlström, Anders
    KTH, Superseded Departments (pre-2005), Infrastructure and Planning.
    A joint between-day and within-day activity based travel demand with forward looking individualsManuscript (preprint) (Other academic)
    Abstract [en]

    Including day-to-day planning to account for systematic variability in activity participation has the potential to further improve travel demand models. This paper introduce a dynamic discrete choice model of day-to-day and within-day planning in a joint framework. No model up to date jointly treats within-day and day-to-day planning with individuals that take future days into account. The model is estimated using a combination of a small survey with week long data and a larger single day travel survey. A static, myopic and forward looking version of the model is estimated. There is a big improvement in model fit when moving from a static to a dynamic model, but allowing forward-looking behaviour gives a relatively small additional improvement. As a policy test, grocery stores are closed on Sundays. The myopic model predicts that people as a consequence will shop more on Mondays-Thursdays and therefore unintuitively also less on Saturdays. The forward looking model also predicts increased shopping on weekdays but mainly that people will shop more on Saturdays anticipating that stores are closed on Sundays.

  • 148.
    Blom Västberg, Oskar
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, System Analysis and Economics. Royal Institute of Technology.
    Karlström, Anders
    KTH, Superseded Departments (pre-2005), Infrastructure and Planning. KTH, School of Architecture and the Built Environment (ABE), Transport Science, System Analysis and Economics.
    Discount factors greater than or equal to one in infinite horizon dynamic discrete choice modelsManuscript (preprint) (Other academic)
    Abstract [en]

    In this paper, the theory on infinite horizon DDCM's is extended to allow for discount factors greater than or equal to one. The proposed methods are applied to Rust's (1987) bus engine replacement model, where a discount factor of 1.075 is identified using grid search. The infinite horizon problem with and without a terminal state are treated separately. Sufficient conditions are given for the existence of solutions to Bellman's equation in the terminal state problem and to a normalized version of Bellman's equation in the non-terminal state setting. If a terminal state exists, acting according to Bellman's equation still yields the maximum expected total utility under derived conditions on the one-stage utility functions and reachability of the terminal state. In the non-terminal state problem, $\beta=1$ implies that individuals maximize the average cost per stage, but for $\beta>1$ no rationale for acting according to Bellman's equation, even when it has a solution, has been found.

  • 149.
    Blom Västberg, Oskar
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, System Analysis and Economics. Royal Institute of Technology.
    Karlström, Anders
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, System Analysis and Economics.
    Jonsson, R. Daniel
    KTH, School of Architecture and the Built Environment (ABE), Centres, Centre for Transport Studies, CTS. KTH, School of Architecture and the Built Environment (ABE), Transport Science.
    Sundberg, Marcus
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, System Analysis and Economics.
    A dynamic discrete choice activitybased travel demand modelManuscript (preprint) (Other academic)
    Abstract [en]

    During the last decades, many activity-based models have been developed in the literature. However, especially in random utility based models timing decisions are often treated poorly or inconsistently with other choice dimensions. In this paper we show how dynamic discrete choice can be used to overcome this problem. In the proposed model, trip decisions are made sequentially in time, starting at home in the morning and ending at home in the evening. At each decision stage, the utility of an alternative is the sum of the one-stage utility of the action and the expected future utility in the reached state.

    The model generates full daily activity schedules with any number of trips that each is a combination of one of 6 activities, 1240 locations and 4 modes. The ability to go from all to all locations makes evaluating the model very time consuming and sampling of alternatives were therefore used for estimation. The model is estimated on travel diaries and simulation results indicates that it is able to reproduce timing decisions, trip lengths and distribution of the number trips within sample.

    To explain when people perform different activities, two sets of parameters are used: firstly, the utility of being at home varies depending on the time of day; and secondly, constants determine the utility of arriving to work at specific times. This was enough to also obtain a good distribution of the starting times for free-time activities.

  • 150.
    Boqvist, Simon
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport and Location Analysis.
    A neurocomputational perspective on behavioral economics: A study of emotional processes.2011Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    In this study we have used a neural network model in order to investigate the impact of emotional processes on economic phenomena. We have built a replica of a model presented by Frank and Claus (2006, Anatomy of a Decision: Striato-Orbitofrontal Interactions in Reinforcement Learning, Decision Making, and Reversal, Psychological Review), although using other software. The model displays, similar to the one referred to above, the characteristics that constitute prospect theory. Additionally, we take a first step toward investigating what explanatory power this model might have in studying the influence of emotions on economic decision-making. We note that by externally altering the activity level in the amygdala, a brain region that has been proven essential for emotional reactions, the risk attitudes of the model can be manipulated. We find that a decrease in activity in the amygdala implies a lower degree of risk-averse, as well as a higher degree or risk-seeking, behavior. Finally, we conclude that response times are longer and choice uncertainty higher for tasks that involve only negative outcomes as compared to tasks that involve partially or exclusively positive outcomes, a result that can be linked to e.g. decision field theory.

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