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  • 1. Abate, M.
    et al.
    De Jong, Gerard
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Centra, Centrum för transportstudier, CTS.
    The optimal shipment size and truck size choice - The allocation of trucks across hauls2014Ingår i: Transportation Research Part A: Policy and Practice, ISSN 0965-8564, E-ISSN 1879-2375, Vol. 59, s. 262-277Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    There has been a growing interest in understanding how firms allocate their trucks across hauls, and how this allocation changes under various economic environments. This study investigates how variations in route/haul, carrier and vehicle characteristics affect the optimal vehicle size choice and the associated choice of shipment size. We show that the two choices are derived from the same optimization problem. There can be a continuum of shipment sizes, but decision-makers in freight transport have to choose from a limited number of vehicle alternatives. Therefore, we use a discrete-continuous econometric model where shipment size is modeled as a continuous variable, and vehicle size/type choice as a discrete variable. The results indicate that when faced with higher demand, and during longer trips firms are more likely to use heavier vehicles and ship in larger quantities which suggest that firms are realizing economies of scale and economies of distance. The study also discusses the effect of vehicle operating cost on the vehicle selection process and its policy implications.

  • 2.
    Abbasi, Saeed
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion (Inst.), Maskinelement.
    A study of nanostructured particles in railway tunnels2013Rapport (Övrigt vetenskapligt)
  • 3.
    Abenoza, Roberto
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö.
    Cats, Oded
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Transportplanering. Department of Transport and Planning, Delft University of Technology, P.O. Box 5048, GA Delft, 2600, Netherlands.
    Susilo, Yusak
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö. KTH, Skolan för industriell teknik och management (ITM), Centra, Integrated Transport Research Lab, ITRL.
    Determinants of traveler satisfaction: Evidence for non-linear and asymmetric effects2019Ingår i: Transportation Research Part F: Traffic Psychology and Behaviour, ISSN 1369-8478, E-ISSN 1873-5517, Vol. 66, s. 339-356Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Classifying public transport service attributes based on their influence on overall traveler satisfaction can assist stakeholders and practitioners in introducing cost-efficient measures. To date most studies employed methods that were based on the assumption that the impact of service attributes on traveler satisfaction is entirely linear and symmetric. This study examines whether service attributes have a non-linear and asymmetric influence on the overall travel experience by employing the Three-factor theory (basic, performance and exciting factors). The analysis is conducted for different traveler segments depending on their level of captivity, travel frequency by public transport and travel mode used, and is based on a relatively large sample size collected for Stockholm County. Moreover, the estimated models control for important socio-demographic and travel characteristics that have been insofar overlooked. Results are presented in the form of a series of multi-level cubes that represent different essentiality of traveler needs which provide a useful methodological framework to further design quality service improvements that can be applied to various geographical contexts. Our findings highlight that a “one size fits all” approach is not adequate for identifying the needs of distinct traveler segments and of travelers using different travel modes. Furthermore, two-thirds of the attributes are consistently classified into the same factor category which entails important policy implications. This research deepens and expands the very limited knowledge of the application of the three-factor theory in the transport field.

  • 4.
    Abenoza, Roberto
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Systemanalys och ekonomi.
    Cats, Oded
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Transportplanering, ekonomi och teknik. TU Delft.
    Susilo, Yusak
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Systemanalys och ekonomi.
    How does travel satisfaction sum up?: Decomposing the door-to-door experience for multimodal trips2018Ingår i: Transportation, ISSN 0049-4488, E-ISSN 1572-9435, Vol. 46, nr 5, s. 1615-1642Artikel i tidskrift (Övrigt vetenskapligt)
    Abstract [en]

    Understanding how satisfaction with individual trip legs aggregates to the overall travel experience for different types of trips will enable the identification of the trip legs that are most impactful. For this purpose we analyze data on retrospective evaluations of entire multi-modal trip experiences and satisfaction with individual trip legs. We formulate and describe alternative aggregation rules and underpin them in theory and previous empirical findings. The results of a series of regression models show that for a large number of multi-modal trip configurations normative rules can better reproduce overall travel satisfaction than heuristic rules. This indicates that all trip legs need to be considered when evaluating the overall travel experience, especially for trips legs involving waiting and/or transferring time. In particular, weighting satisfaction with individual trip legs with perceived trip leg durations yielded the best predictor of overall travel satisfaction. No evidence for a disproportional effect of the last or most exceptional part of the trip was found. This research contributes to the literature on combining multi-episodic experiences and provides novel empirical evidence in the transport domain. 

  • 5.
    Abenoza, Roberto
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Systemanalys och ekonomi.
    Cats, Oded
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Transportplanering, ekonomi och teknik. TU Delft.
    Susilo, Yusak
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Systemanalys och ekonomi.
    Investigating the nature of Public Transport service attributes2018Ingår i: Transportation Science, ISSN 0041-1655, E-ISSN 1526-5447Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Classifying public transport service attributes based on their influence on overall traveler satisfaction can assist stakeholders and practitioners in introducing cost-efficient measures. To date most studies employed methods that were based on the assumption that the impact of service attributes on traveler satisfaction is entirely linear and symmetric. This study examines whether service attributes have a non-linear and asymmetric influence on the overall travel experience by employing the Three-factor theory (basic, performance and exciting factors). The analysis is conducted for different traveler segments depending on their level of captivity, travel frequency by public transport and travel mode used, and is based on a relatively large sample size collected for Stockholm County. Moreover, the estimated models control for important socio-demographic and travel characteristics that have been insofar overlooked. Results are presented in the form of a series of multi-level cubes that represent different essentiality of traveler needs which provide a useful methodological framework to further design quality service improvements that can be applied to various geographical contexts. Our findings highlight that a “one size fits all” approach is not adequate for identifying the needs of distinct traveler segments and of travelers using different travel modes. Furthermore, two-thirds of the attributes are consistently classified into the same factor category which entails important policy implications. This research deepens and expands the very limited knowledge of the application of the three-factor theory in the transport field.

  • 6.
    Abenoza, Roberto F.
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö.
    Liu, C.
    Cats, Oded
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap. Delft University of Technology, Netherlands.
    Susilo, Yusak
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö.
    What is the role of weather, built-environment and accessibility geographical characteristics in influencing travelers’ experience?2019Ingår i: Transportation Research Part A: Policy and Practice, ISSN 0965-8564, E-ISSN 1879-2375, Vol. 122, s. 34-50Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We examine the effect of weather, accessibility and built-environment characteristics on overall travel experience as well as the experience with the latest trips. These are factors that are often disregarded in the travel satisfaction literature even though they are believed to largely influence the first mile of the door-to-door trip. This study fills a research gap in investigating all these factors by using, amongst other, a relatively large travel satisfaction survey from years 2009 to 2015 and by focusing on urban and peri-urban geographical contexts, the city and county of Stockholm (Sweden), respectively. The ordered logit model results show that county dwellers living close to a metro station and in well linked-to-all areas report higher overall travel satisfaction evaluations. In addition, precipitation and ground covered with snow have a negative influence on travel satisfaction. Our findings indicate that built-environment characteristics exert a rather weak influence on the travel experience, especially in the peri-urban context. However, some aspects such as living in areas with medium densities, low income and with high safety perceptions around public transport stations are associated with higher satisfaction levels. In turn, areas with single land uses are found to have lower travel satisfactions. These results are important for public transport planners and designers in devising measures to prevent and mitigate the negative outcome of some weather conditions and to conceive better designed transit oriented developments.

  • 7.
    Abenoza, Roberto F.
    et al.
    KTH.
    Romero-Torres, J.
    Cats, Oded
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Transportplanering. Delft University of Technology, Netherlands.
    Susilo, Y. O.
    User experiences and perceptions of women-only transport services in Mexico2020Ingår i: Gendering Smart Mobilities, Taylor and Francis , 2020, s. 188-209Kapitel i bok, del av antologi (Övrigt vetenskapligt)
    Abstract [en]

    Personal safety perceptions impact upon not only travellers’ behaviour and satisfaction but may also diminish their general well-being and health. These effects are particularly negative among female travellers, a group which feels especially vulnerable from certain types of aggression. To tackle women’s personal safety problems several cities around the world introduced transport for women only. Data from Mexico City and its metropolitan area is used to examine how the characteristics of female travellers and of their trips impact upon travel satisfaction with public transport for women only for different travel modes (metro, city bus, and metropolitan BRT) and users based on their previous victimisation. This chapter demonstrates that female travellers’ appreciation of public transport for women only services varies as a function of some of their socio-demographic and travel characteristics (some age groups, trip purposes, and travel frequency). Considering the strength of the marginal effect’s coefficient from a number of ordered logit models three travel attributes should be prioritised: (1) level of satisfaction with travelling with women only, (2) reducing exposure to verbal aggressions, (3) and meeting travellers’ waiting time expectations. This study may help stakeholders identify, target, and prioritise female travellers’ groups which are least satisfied with the service. In addition, this chapter provides some policy recommendations and highlights the role of infrastructure that may help improve the overall travel experience. 

  • 8.
    Abid, Muhammad
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Industriell ekonomi och organisation (Inst.). Högskolan i Gävle, Sweden.
    Bengtsson, Lars
    Dabhilkar, Mandar
    Factors affecting shifts in global supply chain networks: A configurational approach2013Ingår i: Proceedings of the 20th International Annual EurOMA conference, Dublin, Ireland, 9-12 June 2013, 2013, 2013Konferensbidrag (Refereegranskat)
    Abstract [en]

    In certain situations, global companies strive to take advantage of short-term changes in economic and exchange rates on the never-ending journey of competitiveness. This paper seeks to extend Ferdows’s (2008) production network models by adding the factors affecting shifts between rooted and footloose network configurations. Two companies were selected in order to illustrate the models and reveal other possible factors. The identified factors are differentiated in terms of configuration and coordination and merged in a matrix. The trends and implications on global supply chains are also discussed.

  • 9.
    Abourraja, Mohamed Nezar
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Medicinteknik och hälsosystem, Hälsoinformatik och logistik. Ecole Cent Casablanca, Casablanca, Morocco..
    Rouky, Naoufal
    Euro-Mediterranean University, Fez, Morocco.
    Kornevs, Maksims
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Medicinteknik och hälsosystem, Hälsoinformatik och logistik.
    Meijer, Sebastiaan
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Medicinteknik och hälsosystem, Hälsoinformatik och logistik.
    Kringos, Nicole
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad. Euro Mediterranean Univ, Fes, Morocco..
    A simulation-based decision support framework devoted to Ro-Ro terminals: Design, implementation and evaluation2023Ingår i: Computers & industrial engineering, ISSN 0360-8352, E-ISSN 1879-0550, Vol. 180, s. 109248-, artikel-id 109248Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    As a type of intermodal terminal, pure Ro-Ro terminals are one of the most important logistic hubs in the supply chain for rolling freight stored in containerized and wheeled steel boxes. These large-scale systems are highly complex, with nonlinear and hard-to-predict behavior evolving in a stochastic environment. Consequently, making decisions about any problem thereof is no mean feat, particularly for terminal planners. To assist them in decision-making, a pool of relevant models and tools have been developed over the years in the literature. Nevertheless, models that are oriented toward specific objectives dominate, and generic ones are rare. This paper tries to fill this gap and proposes a generic framework to be used as a factory to create specific decision support models based on simulation for pure Ro-Ro terminals. This framework is formulated following two artifacts: (1) the known classification of key performance indicators combined with the typical functional and physical organization of pure Ro-Ro terminals; (2) the three main arteries of harbor systems, namely flows, decisions and operations. Then a scalable way of making decisions based on a flexible form of the cost function weighted according to a set of coefficients is integrated. These designed coefficients allow decision-makers a wide flexibly in choosing how the best solutions are determined. An application of this framework is illustrated through a real case study, where the weights are estimated using an expert-profiling based approach then pushed into the OptQuest optimizer to be calibrated before analyzing the results. These results are aggregated, then expressed as scores on a scale of 0 to 1. This is to help terminal planners to easily identify the worst and best planning scenarios as well as the relationships and compatibilities between the involved handling rules to suggest different alternatives for managing operations.

  • 10.
    Adolphson, Marcus
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Urbana och regionala studier.
    Fröidh, Oskar
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Transportplanering.
    Impact on urban form by the localization of railway stations: Evidence from Sweden2019Ingår i: Cities, ISSN 0264-2751, E-ISSN 1873-6084, Vol. 95, artikel-id 102362Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Since the 1990s a number of new railway stations have been established in Sweden on new or rerouted lines, while other stations have been reconstructed at their original locations. Some stations were located in urban surroundings, others in semi-urban or peripheral locations depending on the trade of between regional speed, and local urban circumstances. The urban form consequences depending on station localisation of these transport infrastructure investments are nonetheless unknown. In order to provide a basis for future planning, this research aims to provide knowledge on urban form consequences of relocating railway stations. 13 stations were selected in a case study. Changes in urban densities from 1993 to 2013 were analysed by a combination of kernel techniques and estimation of monocentric density models. Stations within an urban and semi-urban environments show strong agglomeration tendencies. Within peripheral environments, the urban development was unclear or even negative. In an urban environment, the location of the station still attracted more urban resources compared to the location of the urban density centre. These findings should be understood in the light of a market-oriented socio-economic context since 1990th influencing the planning system and the development of urban form.

  • 11.
    Agrawal, Tarun Kumar
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Hållbar produktionsutveckling (ML), Avancerad underhållsteknik och produktionslogistik.
    Kalaiarasan, Ravi
    KTH, Skolan för industriell teknik och management (ITM), Hållbar produktionsutveckling (ML), Avancerad underhållsteknik och produktionslogistik.
    Olhager, Jan
    Lund University.
    Wiktorsson, Magnus
    KTH, Skolan för industriell teknik och management (ITM), Hållbar produktionsutveckling (ML), Avancerad underhållsteknik och produktionslogistik.
    Understanding Supply Chain Visibility Through Experts’ Perspective: A Delphi Based Approach2021Ingår i: Advances in Production Management Systems. Artificial Intelligence for Sustainable and Resilient Production Systems: IFIP WG 5.7 International Conference, APMS 2021, Nantes, France, September 5–9, 2021, Proceedings, Part IV / [ed] Alexandre Dolgui, Alain Bernard, David Lemoine, Gregor von Cieminski, David Romero, Cham: Springer Nature , 2021, Vol. 633, s. 189-196Konferensbidrag (Refereegranskat)
    Abstract [en]

    Visibility in production logistics and across the supply chain has become a key concern for organizations. Its need has been further emphasized due to the current COVID 19 crisis. Organizations find it challenging to prepare the internal logistics and supply chain, and quickly respond to such unexpected events, due to low visibility. Against this backdrop, the paper, which is a work-in-progress, systematically documents different factors influencing supply chain visibility and crucial information that should be collected and shared among supply chain partners for better visibility. A Delphi analysis is being conducted with twenty-six supply chain experts from various globally recognized enterprises with manufacturing units located worldwide. The study starts with a short open-ended questioner to collect a comprehensive list of antecedents, drivers, barriers, effects, and visibility information based on the qualitative response from the experts. The preliminary results from the first round of the Delphi analysis indicate that risk management, environmental sustainability, and supply chain control are some of the key drivers. Lack of IT infrastructure and maturity are some of the barriers, integrated systems, and technology maturity are among the key antecedents and gaining planning capability and better customer service are some of the positive effects of supply chain visibility as per the experts’ opinion. In addition, information related to planning, supplier location, and deviation are among the crucial ones that require the collection and sharing for better supply chain visibility. This research study is among the few that empirically explores factors influencing supply chain visibility and generates new insights as to why the barriers can be difficult to overcome in complex supply chain settings.

  • 12.
    Ahmad Termida, Nursitihazlin
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Transportvetenskap, Systemanalys och ekonomi. Universiti Tun Hussein Onn Malaysia, Faculty of Civil and Environmental Engineering, Department of Infrastructure and Geomatic Engineering.
    Understanding Individuals' Learning and Decision Processes in a Changing Environment by Using Panel Data2017Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    When a new transport service is introduced, people have to learn and familiarize themselves with the new service before they decide to adopt it. These processes are developed over time, thus produce dynamics in individuals’ behavioural responses towards the service. This affects the demand of the new service, thus affect revenues. Available studies have examined the factors influencing these responses from microeconomic perspectives. The influence of the theory-based subjective factors has not been examined empirically. Understanding these would assist transport and urban planners to design a better marketing strategy to increase the market share of the new service. A change in seasons affect individuals’ activity-travel decisions, thus produce dynamics in activitytravel patterns in different seasons. Individuals’ constraints, in a form of mandatory activities (working/studying), are influencing individuals’ decisions to participate in day-to-day nonmandatory activities (leisure and routine activities). The interdependency between travel demand, time allocation and mode choice that considers interactions between mandatory and non-mandatory activities, in different seasons is less explored. Understanding these would assist transport planners and operators to manage travel demand strategies across different seasons of the year and provide better transportation systems for all individuals. This thesis includes five papers. Paper I explores individuals’ characteristics of the quick-response and the adopters of the new public transport (PT) service and examines the temporal effects. Paper II investigates the subjective factors influencing a quick-response to the new PT service by proposing a modified attitude-behaviour framework. Paper III and IV analyse the effects of seasonal variations and individuals’ constraints on their day-to-day activity-travel decisions and patterns. Paper V analyses the attrition and fatigue in the two-week travel diary panel survey instrument.

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  • 13.
    Ahmad Termida, Nursitihazlin
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Transportvetenskap, Systemanalys och ekonomi. Universiti Tun Hussein Onn Malaysia, Faculty of Civil and Environmental Engineering, Department of Infrastructure and Geomatic Engineering.
    Susilo, Yusak
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Transportvetenskap, Systemanalys och ekonomi.
    Franklin, Joel
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Transportvetenskap, Systemanalys och ekonomi.
    Attrition and Fatigue in a Four Waves of Two-Week Travel Diary: A Case Study in Stockholm, SwedenManuskript (preprint) (Övrigt vetenskapligt)
    Abstract [en]

    This paper describes a four-wave panel survey design and implementation collected on individual level, consisting of three survey’s instrument namely, self-reported two-week travel diary, on-line psychological questionnaire, and self-reported mental map-related questions. The panel survey is built with the aim to examine individuals’ behavioural changes when a new tram extension line in western sub-urban areas of Stockholm, Sweden, was introduced in October 2013. The survey duration took approximately seven months’ period and the data collected covers all four different seasons of the year, which make it wealth of information. The analysis of attrition and fatigue was done on the two-week travel diary survey instrument only. It is found that the overall attrition rate is 34.3% of the total participants (102 individuals) in the Wave 1 survey, which is considered large. The attrition rate between consecutive waves, however, is considered low which is within the range of 7% to 10%. Based on the binary logit models, there are no systematic tendencies of the dropouts’ characteristics from wave to wave to be found, indicating attrition is purely random. There is no correlation between immobile days and missing trips per day are to be found between-waves. The results of the binary logit model on missing trip show that personal attributes, temporal factors (e.g. weekdays and waves) and travel characteristics (e.g. home-based trip, trip purpose, travel distance and number of inter-modal transfers) significantly affect the missing trip but no indication of fatigue appears.

  • 14.
    Ahmad Termida, Nursitihazlin
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Transportvetenskap, Systemanalys och ekonomi. Universiti Tun Hussein Onn Malaysia, Faculty of Civil and Environmental Engineering, Department of Infrastructure and Geomatic Engineering.
    Susilo, Yusak
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Transportvetenskap, Systemanalys och ekonomi.
    Franklin, Joel
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Transportvetenskap, Systemanalys och ekonomi.
    Subjective Factors Influencing Individual's Response to a New Public Transport ServiceManuskript (preprint) (Övrigt vetenskapligt)
    Abstract [en]

    The timing and nature of people’s responses can be expected to vary when a new element enter their environment. For example, when an individual is provided with a new or modified transport service. This time-scale of behavioural responses will affect the patronage of, and short- and long-term demands on the new service over time. Understanding the underlying factors that influence an individual’s response over time to a new or modified transport service would enable us to identify trigger factors that make the new service attractive from an individual’s point of view. Chatterjee (2001) and Douglas (2003) argued that motives other than instrumental factors related to public transport use, such as attitudes, awareness, travel habits and learning processes, can influence individual responses over time to changes in the travel environment. Unfortunately, despite their importance, there have been few studies that examined this argument empirically. To address this research gap, this paper aims to investigate the influences of subjective factors on individuals’ responses to the introduction of a modified public transport (PT) service over time by proposing and testing an alternative model that modifies the theory of planned behaviour (TPB) model framework. This paper also aims to investigate the behavioural change in terms of attitudes and perceptions on individuals’ resources and constraints in using a modified PT service over time after its introduction. The case study involves the new extension of a tram line connecting the suburbs of Alvik and Solna Centrum in Stockholm, Sweden. Four waves of a panel survey were conducted with 96 individuals who lived along the new service, from just before the new service was introduced and until seven months after its introduction. A structural equation modelling technique was used to estimate the relationships between behavioural constructs and panel data, then incorporate them into a discrete choice model. The results show that intention influences individual’s quick-response choice. The panel analysis shows that past behaviour in using the new service influenced current behaviour, and that perceived walking distance in using the service consistently influenced the frequency of using the new service over time.

  • 15.
    Ahmad Termida, Nursitihazlin
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Transportvetenskap, Systemanalys och ekonomi. Universiti Tun Hussein Onn Malaysia, Faculty of Civil and Environmental Engineering, Department of Infrastructure and Geomatic Engineering.
    Susilo, Yusak
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Transportvetenskap, Systemanalys och ekonomi.
    Franklin, Joel
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Transportvetenskap, Systemanalys och ekonomi.
    Liu, Chengxi
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Transportvetenskap, Systemanalys och ekonomi. VTI.
    Understanding Seasonal Variation in Individual's Activity Participation and Trip Generation by Using Four Consecutive Two-Week Travel DiaryManuskript (preprint) (Övrigt vetenskapligt)
    Abstract [en]

    This paper explores the interactions between travel demand, time allocation and mode choice in different seasons by jointly modeling the work and/or study, routine and leisure activity-travel engagements of 67 individuals in Stockholm, Sweden. A longitudinal panel two-week travel diary data collected in four consecutive waves over a span of seven months period that covers all four different seasons; autumn, winter, spring and summer, were analysed by using simultaneous Tobit models. The model was applied to explore the interactions among each activity-travel indicator, and individuals’ unique characteristics and endogeneity in activity-travel engagements between different seasons were also considered in the model system. The results of models reveal clear trade-offs between mandatory activities (work and/or study) and non-mandatory activities (routine and leisure), regardless of any seasons, although the magnitudes vary between seasons. There is also a positive mutual endogeneity relationship between number of trips and activity duration within the same activity type. The trade-offs between work and/or study trips towards routine and leisure trips are larger in winter and spring respectively, than in other seasons. It is also found that mode effects on travel time for conducting mandatory activity are much larger in spring than in other seasons. However, the effects of public transport and slow modes on travel time for leisure activities are much larger in summer than in other seasons.

  • 16.
    Ahmad Termida, Nursitihazlin
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Transportvetenskap.
    Susilo, Yusak
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Transportvetenskap.
    Franklin, Joel P.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Transportvetenskap.
    Examining the effects of out-of-home and in-home constraints on leisure activity participation in different seasons of the year2016Ingår i: Transportation, ISSN 0049-4488, E-ISSN 1572-9435, s. 1-25Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Using multi-day, multi-period travel diaries data of 56 days (four waves of two-week diaries) for 67 individuals in Stockholm, this study aims to examine the effects of out-of-home and in-home constraints (e.g. teleworking, studying at home, doing the laundry, cleaning and taking care of other household member[s]) on individuals’ day-to-day leisure activity participation decisions in four different seasons. This study also aims to explore the effects of various types of working schedules (fixed, shift, partial- and full-flexible) on individuals’ decisions to participate in day-to-day leisure activities. A pooled model (56 days) and wave-specific models (14 days in each wave) are estimated by using dynamic ordered Probit models. The effects of various types of working schedules are estimated by using 28 days of two waves’ data. The results show that an individual’s leisure activity participation decision is significantly influenced by out-of-home work durations but not influenced by in-home constraints, regardless of any seasons. Individuals with shift working hours engage less in day-to-day leisure activities than other workers’ types in both spring and summer seasons. The thermal indicator significantly affects individuals’ leisure activity participation decisions during the autumn season. Individuals exhibit routine behaviour characterized by repeated decisions in participating in day-to-day leisure activities that can last up to 14 days, regardless of any seasons.

  • 17.
    Ahmad Termida, Nursitihazlin
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Transportvetenskap, Transportplanering, ekonomi och teknik.
    Susilo, Yusak O.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Transportvetenskap, Transportplanering, ekonomi och teknik.
    Franklin, Joel P.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Transportvetenskap, Transportplanering, ekonomi och teknik.
    Observing dynamic behavioural responses due to the extension of a tram line by using panel survey2016Ingår i: Transportation Research Part A: Policy and Practice, ISSN 0965-8564, E-ISSN 1879-2375, Vol. 86, s. 78-95Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Using a four-wave panel survey of individuals' trips and psychological attributes collected among residents along a new tram line extension in the city of Stockholm, Sweden, this study aims to investigate factors that determine the individuals' learning and decision-making processes in using a new transport option. This includes investigating which group of travellers have used the new tram extension earlier than others, and integrated the tram extension as a part of their daily travel patterns. This paper also describes the design and construction of the four-wave panel data collection, which was collected from two weeks before and up to seven months after the opening of the new option. Descriptive analysis shows that within a seven-month period, 79% of the respondents tried the new tram extension but only 14.9% of them adopted the new option as their daily travel mode. During the observed period, about 49.3% of the respondents migrated between travel modes for non-discretionary trips. Further multivariate analysis shows that middle-income travellers and travellers who owned car(s) used the new tram extension earlier than others. The effect of past experience on the current use of the tram extension on a day-to-day basis was also examined by using a mixed logit model with panel data. The purpose of the model is to examine whether individuals' daily experiences with the new tram extension that result from repeated previous choices would affect their decisions to maintain using the new option in subsequent waves.

  • 18.
    Aid, Graham
    KTH, Skolan för industriell teknik och management (ITM), Industriell ekologi.
    Industrial Ecology Methods within Engagement Processes for Industrial Resource Management2013Licentiatavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    The global use of resources such as materials, energy, and water has surpassed sustainable levels by many accounts.  The research presented here was explicitly normative in its aim to improve the understanding of, and make sustainable change toward highly systemic issues of resource management.  The core methods chosen to work toward this aim were bottom up action research procedures (including stakeholder engagement processes) and industrial ecology analysis tools.  These methods were employed and tested in pragmatic combination through two of the author’s case study projects. The first case study, performed between 2009 and 2012, employed a multi-stakeholder process aimed at improving the cycling of construction and demolition waste in the Stockholm region.  The second case study produced a strategic tool (Looplocal) built for facilitating more efficient regional industrial resource networks. While the highly participative aim of the cases required a larger contribution of resources than that of more closed studies, it is arguable that the efficacy of approaching the project aims is improved through their employment. 

    Ladda ner fulltext (pdf)
    Aid - Industrial Ecology Methods within Engagement Processes for Industrial Resource Management
  • 19.
    Aid, Graham
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Industriell ekologi.
    Brandt, Nils
    KTH, Skolan för industriell teknik och management (ITM), Industriell ekologi.
    Lysenkovac, Mariya
    Smedberg, Niklas
    KTH, Skolan för industriell teknik och management (ITM), Industriell ekologi.
    Looplocal: a Heuristic Visualization Tool for the Strategic Facilitation of Industrial Symbiosis2012Ingår i: Greening of Industry Netowrk Proceedings / [ed] Leo Baas, 2012Konferensbidrag (Refereegranskat)
    Abstract [en]

    Industrial symbiosis (IS) developments have been differentiated as ‘self organized’, ‘facilitated’, and ‘planned’. This article introduces a tool that has been built with objectives to support the strategic facilitation of IS. ‘Looplocal’ is a visualization tool built to assist in 1) the identification of regions prone to new industrial symbiosis activities 2) market potential exchanges to key actors and 3) assist aspiring facilitators to assess the various strategies and social methodologies available for the initial phases of a facilitated industrial symbiosis venture. This tool combines life cycle inventory (LCI) data, waste statistics, and national industrial data (including geographic, activity, economic, and contact information) to perform a heuristic analysis of raw material and energy inputs and outputs (wastes). Along with an extensive list of ‘waste to raw material’ substitutions (which may be direct, combined, or upgraded) gathered from IS uncovering studies, IS organizations, and waste and energy professionals; heuristic regional output to input ‘matching’ can be visualized. On a national or regional scale the tool gives a quick overview of what could be the most interesting regions to prioritize resources for IS facilitation. Focusing in on a regional level, the tool visualizes the potential structure of the network in that region (centralized, decentralized, or distributed), allowing a facilitator to adapt the networking approach correspondingly. The tool also visualizes potential IS transfer information, along with key stakeholder data. The authors have performed a proof of concept run of this tool in the ‘industrial disperse’ context of Sweden. In its early stages of application, the method has proven capable of identifying regions prone to the investment of facilitators’ resources. The material focus and custom possibilities for the tool show potential for a wide spectrum of potential facilitators: from waste management companies (using the tool as a strategic market analysis tool) to national or regional authorities looking to lower negative environmental impacts, to ‘sustainable’ industry sectors looking to strengthen market positioning. In conjunction with proper long term business models, such a tool could be reusable itself over the evolution of facilitation activities and aims.

  • 20.
    Aidinnezhad, Negin
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Byggteknik och design.
    Stendahl, Martin
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Byggteknik och design.
    Optimering av sjötransport: Logistikflöde av prefabricerade brodelar i Mälaren2019Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Getingmidjan är Sveriges mest trafikerade järnvägssträcka enligt beställaren Trafikverket. En omfattande renovering sker vid järnvägssträckan mellan Stockholm Central och Stockholm Södra Station. Det här examensarbete kommer att avgränsas till sjötransportslogistiken i delprojektet Anläggning – som har hand om Söderströmsbron. Logistiken i uppsatsen uppmärksammar brobytet av Söderströmsbron som fraktas under Sommaren 2019. Söderströmsbron innefattar godstransportslogistik för sjötransporten Tallinn till destinationen Riddarfjärden. Arbetet fokuserar på tre olika konfigurationer som består av: pråmar, brosektioner och bogserbåtar. Där tas hänsyn till bredd, längd, djupgående och segelfri höjd. Brosektionerna kommer att bogseras med utgångspunkten i Kopli Hamn i Estland. Uppsatsen ser till att utreda alternativa rutter i Mälaren med starthamnen i Södertälje, därefter kartläggs rutter från Södertälje till mellanhamnen, där svetsningen kommer att ske. Till sist anlöper brosektionerna till Riddarfjärden. Resultatet påvisade att den främsta flaskhalsen var kajlängden vid mellanhamnen som inte var tillräcklig för de två brodelarna SS1 och SS2, som ska svetsas ihop. De enda hamnarna som motsvarade de ställda kraven var Djuphamnen i Köping och den befintliga hamnen i Västerås. Med observationer, intervjuer och enkätundersökning har empirin försökt finna visuella verktyg som kan implementeras på Trafikverket för att förbättra kommunikationen. Empiriska utredningen har pekat på att byggnadsprojekt generellt har brister i initieringsskedet. Det finns även svårigheter i att föra en öppen dialog med samarbetspartners. Det betonades också hur ledarskapet har en stor betydelse för teamet. Vid samordningsmöten visar empirin att det finns förbättringspotential, aktörer lyssnar främst till sin egen agenda och sällan på andras synpunkter. Mötesprotokollföringen behöver moderniseras. Ett möte i veckan är lagom. Både stora som små projekt använder sig av samma projektstyrningsmedel oberoende av projektets storlek. Rapporten analyserar aspekterna ovan för att komma fram till passande lean metodik i form av visuell planering för mötesstrukturen. Resultatet förespråka Kanban-metodik och Peabs projektstyrningsmodell. Examensarbetet har inte haft intentionen att producera vattentäta lösningar, utan har syftat till att förse underlag som Trafikverket rekommenderas att se över för att modernisera projektledningen på möten. Vidare har kartläggning av hamnen Underås, Enhörna tagits fram som ett framtida alternativ till stora godstransporter. Platsen är centralt lokaliserad i Mälaren vid frakt som utgår från Södertälje – detta bidrar till en minskad ledtid. Rapporten har velat förenkla olika led i organisationen genom visuella verktyg. Arbetet redogör hur tredje man kan komma att påverkas i framförallt kollektivtrafiken samt sjöfart och väg inför sommaravstängningen som påbörjas kring midsommar. Tänkbara risker som uppstått och kan uppkomma i och med konstruktionen, transporten och avstängningen presenteras.

  • 21.
    Ait Ali, Abderrahman
    et al.
    Swedish National Road and Transport Research Institute (VTI), Malvinas väg 6, 114 28, Stockholm, Sweden; Linköping University, Luntgatan 2, 602 47, Norrköping, Sweden.
    Eliasson, Jonas
    Linköping University, Luntgatan 2, 602 47, Norrköping, Sweden; Swedish Transport Administration (Trafikverket), Solna strandväg 98, 17 154, Solna, Sweden.
    Warg, Jennifer
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Transportplanering.
    Are commuter train timetables consistent with passengers’ valuations of waiting times and in-vehicle crowding?2022Ingår i: Transport Policy, ISSN 0967-070X, E-ISSN 1879-310X, Vol. 116, s. 188-198Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Social cost-benefit analysis is often used to analyse transport investments, and can also be used for transport operation planning and capacity allocation. If it is to be used for resolving capacity conflicts, however, it is important to know whether transit agencies' timetable requests are consistent with the cost-benefit framework, which is based on passenger preferences. We show how a public transport agency's implicit valuations of waiting time and crowding can be estimated by analysing timetables, apply the method to commuter train timetables in Stockholm, and compare the implicit valuations to the corresponding passenger valuations in the official Swedish cost-benefit analysis guidelines. The results suggest that the agency puts a slightly lower value on waiting time and crowding than the passenger valuations codified in the official guidelines. We discuss possible reasons for this and implications for using cost-benefit analysis for capacity allocation. We also find that optimal frequencies are more sensitive to the waiting time valuation than to that of crowding.

  • 22.
    Ait Ali, Abderrahman
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Transportvetenskap, Transportplanering, ekonomi och teknik.
    Lindberg, Per Olov
    KTH.
    Nilsson, Jan-Eric
    Eliasson, Jonas
    Aronsson, Martin
    Disaggregation in Bundle Methods: Application to the Train Timetabling Problem2017Konferensbidrag (Refereegranskat)
    Abstract [en]

    Bundle methods are often used to solve dual problems that arise from Lagrangian relaxations of large scale optimization problems. An example of such problems is the train timetabling problem. This paper focuses on solving a dual problem that arises from Lagrangian relaxation of a train timetabling optimization program. The dual problem is solved using bundle methods. We formulate and compare the performances of two different bundle methods: the aggregate method, which is a standard method, and a new, disaggregate, method which is proposed here. The two methods were tested on realistic train timetabling scenarios from the Iron Ore railway line. The numerical results show that the new disaggregate approach generally yields faster convergence than the standard aggregate approach.

    Ladda ner fulltext (pdf)
    disaggregation in BM
  • 23.
    Ait-Ali, Abderrahman
    et al.
    Swedish National Road and Transport Research Institute (VTI), Malvinas väg 6, 114 28, Stockholm, Sweden, Malvinas väg 6; Linköping University, Bredgatan 32, 602 21, Norrköping, Sweden, Bredgatan 32.
    Kurt, Filiz
    Deutsches Zentrum für Luft-und Raumfahrt e.V. (DLR), Lilienthalplatz 7, 38108, Braunschweig, Germany, Lilienthalplatz 7.
    Isberner, Alessa
    Deutsches Zentrum für Luft-und Raumfahrt e.V. (DLR), Lilienthalplatz 7, 38108, Braunschweig, Germany, Lilienthalplatz 7.
    Odolinski, Kristofer
    Swedish National Road and Transport Research Institute (VTI), Malvinas väg 6, 114 28, Stockholm, Sweden, Malvinas väg 6.
    Berg, Mats
    KTH, Skolan för teknikvetenskap (SCI), Teknisk mekanik, Farkostteknik och Solidmekanik, Väg- och spårfordon samt konceptuell fordonsdesign.
    Assessing Innovations in High-Speed Rail Infrastructure2023Ingår i: Socioeconomic Impacts of High-Speed Rail Systems - Proceedings of the 2nd International Workshop on High-Speed Rail Socioeconomic Impacts, IW-HSR 2022, Springer Nature , 2023, s. 217-233Konferensbidrag (Refereegranskat)
    Abstract [en]

    Innovations in high-speed rail (HSR) have had substantial effects on different stakeholders within and outside the railway system. As part of the European Shift2Rail research programme, several innovative solutions are developed for, among others, improving the HSR infrastructure. The Joint Undertaking behind this research program has set objectives for these innovations in terms of punctuality, capacity, and life cycle costs. With a focus on infrastructure-related innovations for HSR, this paper aims at assessing their impacts in relation to these targets. We review the relevant research literature about the effects of HSR innovations and their assessment. The paper presents a hybrid assessment methodology combing different approaches to assess capacity, punctuality, and cost effects. This contributes to reducing the existing gap that is found in the research literature. Based on a reference scenario for HSR line and collected data from different stakeholders, the results indicate that infrastructure innovations in HSR, being developed within the European Shift2Rail research programme, can contribute to reaching the target set for punctuality. Further innovations in HSR infrastructure and/or other railway assets may be needed to reach additional targets and for more accurate improvement values giving more insights into their impacts.

  • 24.
    Alam, Assad
    KTH, Skolan för elektro- och systemteknik (EES), Reglerteknik.
    Fuel-Efficient Heavy-Duty Vehicle Platooning2014Doktorsavhandling, monografi (Övrigt vetenskapligt)
    Abstract [en]

    The freight transport industry faces big challenges as the demand for transport and fuel prices are steadily increasing, whereas the environmental impact needs to be significantly reduced. Heavy-duty vehicle (HDV) platooning is a promising technology for a sustainable transportation system. By semi-autonomously governing each platooning vehicle at small inter-vehicle spacing, we can effectively reduce fuel consumption, emissions, and congestion, and relieve driver tension. Yet, it is not evident how to synthesise such a platoon control system and how constraints imposed by the road topography affect the safety or fuel-saving potential in practice.

    This thesis presents contributions to a framework for the design, implementation, and evaluation of HDV platooning. The focus lies mainly on establishing fuel-efficient platooning control and evaluating the fuel-saving potential in practice. A vehicle platoon model is developed together with a system architecture that divides the control problem into manageable subsystems. Presented results show that a significant fuel reduction potential exists for HDV platooning and it is favorable to operate the vehicles at a small inter-vehicle spacing. We address the problem of finding the minimum distance between HDVs in a platoon without compromising safety, by setting up the problem in a game theoretical framework. Thereby, we determine criteria for which collisions can be avoided in a worst-case scenario and establish the minimum safe distance to a vehicle ahead. A systematic design methodology for decentralized inter-vehicle distance control based on linear quadratic regulators is presented. It takes dynamic coupling and engine response delays into consideration, and the structure of the controller feedback matrix can be tailored to the locally available state information. The results show that a decentralized controller gives good tracking performance and attenuates disturbances downstream in the platoon for dynamic scenarios that commonly occur on highways. We also consider the problem of finding a fuel-efficient controller for HDV platooning based on road grade preview information under road and vehicle parameter uncertainties. We present two model predictive control policies and derive their fuel-saving potential. The thesis finally evaluates the fuel savings in practice. Experimental results show that a fuel reduction of 3.9–6.5 % can be obtained on average for a heterogenous platoon of HDVs on a Swedish highway. It is demonstrated how the savings depend on the vehicle position in the platoon, the behavior of the preceding vehicles, and the road topography. With the results obtained in this thesis, it is argued that a significant fuel reduction potential exists for HDV platooning.

    Ladda ner fulltext (pdf)
    PhDThesis
  • 25. Alam, Assad
    et al.
    Besselink, Bart
    KTH, Skolan för elektro- och systemteknik (EES), Reglerteknik. KTH, Skolan för elektro- och systemteknik (EES), Centra, ACCESS Linnaeus Centre.
    Turri, Valerio
    KTH, Skolan för elektro- och systemteknik (EES), Reglerteknik. KTH, Skolan för elektro- och systemteknik (EES), Centra, ACCESS Linnaeus Centre.
    Mårtensson, Jonas
    KTH, Skolan för elektro- och systemteknik (EES), Reglerteknik. KTH, Skolan för elektro- och systemteknik (EES), Centra, ACCESS Linnaeus Centre.
    Johansson, Karl Henrik
    KTH, Skolan för elektro- och systemteknik (EES), Reglerteknik. KTH, Skolan för elektro- och systemteknik (EES), Centra, ACCESS Linnaeus Centre.
    Heavy-Duty Vehicle Platooning for Sustainable Freight Transportation A COOPERATIVE METHOD TO ENHANCE SAFETY AND EFFICIENCY2015Ingår i: IEEE CONTROL SYSTEMS MAGAZINE, ISSN 1066-033X, Vol. 35, nr 6, s. 34-56Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The current system of global trade is largely based on transportation and communication technology from the 20th century. Advances in technology have led to an increasingly interconnected global market and reduced the costs of moving goods, people, and technology around the world [1]. Transportation is crucial to society, and the demand for transportation is strongly linked to economic development. Specifically, road transportation is essential since about 60% of all surface freight transportation (which includes road and rail transport) is done on roads [2]. Despite the important role of road freight transportation in the economy, it is facing serious challenges, such as those posed by increasing fuel prices and the need to reduce greenhouse gas emissions. On the other hand, the integration of information and communication technologies to transportation systems-leading to intelligent transportation systems-enables the development of cooperative methods to enhance the safety and energy efficiency of transportation networks. This article focuses on one such cooperative approach, which is known as platooning. The formation of a group of heavy-duty vehicles (HDVs) at close intervehicular distances, known as a platoon (see Figure 1) increases the fuel efficiency of the group by reducing the overall air drag. The safe operation of such platoons requires the automatic control of the velocity of the platoon vehicles as well as their intervehicular distance. Existing work on platooning has focused on the design of controllers for these longitudinal dynamics, in which simple vehicle models are typically exploited and perfect environmental conditions, such as flat roads, are generally assumed. The broader perspective of how platooning can be effectively exploited in a freight transportation system has received less attention. Moreover, experimental validations of the fuel-saving potential offered by platooning have typically been performed by reproducing the perfect conditions as assumed in the design of the automatic controllers. This article focuses on these two aspects by addressing the following two objectives.

  • 26.
    Albrecht, Martin
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Miljöstrategisk analys (fms).
    Enabling socio-technical transitions – electric vehicles and high voltage electricity grids as focal points of low emission futures2017Licentiatavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Today humankind is facing numerous sustainability challenges that require us to question CO2 intensive practices like those present in the transport and energy sector. To meet those challenges, many countries have adopted ambitious climate targets. Achieving such targets requires an understanding of the wider socio-technical context of transitions. The aim of this licentiate thesis is therefore to analyse such socio-technical transitions towards low-emission futures enabled by the electrification of passenger cars and high voltage grid development.

    A combination of different transitions theories (for ex. Multi-level perspective and Technological innovation systems) and institutional theory has been used. To reach the aim paper I analyses the climate impacts of electric vehicles (EVs) and policy measures to achieve a breakthrough scenario for EVs. The results show that a mixture of short and long term policies are needed that take into account the technology development stage and behavioural aspects of EV adopters. Paper II addresses the need to include the high voltage transmission grid and its planning procedures as a central part of debates on transitions. Therefore the opportunities, challenges and reasons for conflict in the established regime are studied. The results show that in order to achieve a sustainable grid development regime, it is necessary to spend time on achieving legitimacy and social sustainability. The third paper uses semi-structured expert interviews and focuses on innovation dynamics for EV adoption. By focusing on dynamics instead of single policy measures, it is possible to grasp interactions within a niche, but also in between a niche, regime and landscape. The results show that strong initial technology legitimacy was needed to start substantial innovation dynamics. This could be further strengthened with a strong and broad coalition of actors. Both those factors led, if present, to an improved variety and match of policy instruments.

    As such this thesis has shown that transitions are not just about technology or policy instruments as such but about the dynamics and processes needed to enable them. This can be relevant in other transitions that otherwise may underestimate the importance of these components.

    Ladda ner fulltext (pdf)
    fulltext
  • 27.
    Albrecht, Martin
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Miljöstrategisk analys (fms).
    System innovation dynamics around electric vehicles. The cases of Norway, Denmark and Sweden.Manuskript (preprint) (Övrigt vetenskapligt)
    Abstract [en]

    This paper focuses on the comparison of electric car innovation patterns in Norway, Sweden and Denmark. Doing so, it takes a closer look at what the most essential dynamics in the systems were over time and what enabled those dynamics. The main research aim is to contribute to a wider understanding of why Norway is so much ahead of Sweden and Denmark in electric car adoption. The purpose is also to adopt a perspective that goes beyond a mere focus on economic policy instruments. In order to do so different theory elements are combined in a framework. These elements stem from the transition theory literature field, especially the technological innovation system (TIS) and the multi-level perspective (MLP). This combination allows analysing the development behind a dynamic, not just when it comes to an innovation itself but also with regards to the established regime. The data is gathered through analysis of existing documents and data as well as a series of 27 expert interviews conducted in the three case countries. The findings suggest that there are important differences in transition patterns that can account for the electric vehicle (EV) diffusion situation we can find nowadays in the three Nordic countries. An important stepping stone was the need for a very strong legitimacy of the original EV vision that is also anchored in a coordinated, sector overarching coalition of actors that thinks strategically and long term. Moreover some general beneficial dynamics could be identified across the countries in question. In Norway these beneficial dynamics can be summarised as a systems motor, in Denmark as a failed entrepreneurial motor that shifted towards a constrained municipal motor and in Sweden as a loosely, coordinated and weaker version of a systems motor.

  • 28.
    Albrecht, Martin
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Miljöstrategisk analys (fms).
    Nilsson, Måns
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Miljöstrategisk analys (fms). Stockholm University, Stockholm Environment Institute.
    Åkerman, Jonas
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Miljöstrategisk analys (fms).
    Electrification of vehicles – policy drivers and impacts in two scenarios.2013Ingår i: Grid Integration of Electric Vehicles in Open Electricity Markets / [ed] Qiuwei Wu, John Wiley & Sons, 2013Kapitel i bok, del av antologi (Refereegranskat)
    Abstract [en]

    This chapter examines current policy drivers of battery electric vehicles (EVs) and plug-in hybrid EVs, the current and anticipated impacts on carbon emissions, as well as what potential role policy can play in enhancing the innovation system and market development around such vehicles in the future. We start with a policy review of key targets in the Nordic countries and the EU, up to 2030, and discuss to what extent they are consistent with industry and expert estimates of how the systems can grow. On the basis of this, the second part elaborates two simple scenarios of EV development in the EU: one breakthrough expansion scenario and one incremental expansion scenario. Building on that is an analysis of the climate impacts of the two scenarios, given different assumptions relating to, for example, electricity production as well as EV penetration in the fleet. The third part examines what policy drivers might be needed to enable the breakthrough scenario, using a technological innovation systems perspective to describe the needed processes, drivers and developments.

  • 29.
    Alemu, Beakal Tadesse
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Transportvetenskap, Transport- och lokaliseringsanalys.
    Collocation of Infrastructuresin Stockholm Airport City: Collocation of infrastructures to foster implementation ofnew transportation systems2010Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
  • 30.
    Alfonsetti, Elisabetta
    et al.
    KTH, Skolan för elektro- och systemteknik (EES).
    Weeraddana, P. C.
    Fischione, Carlo
    KTH, Skolan för elektro- och systemteknik (EES), Reglerteknik.
    Min-max fair car-parking slot assignment2015Ingår i: Proceedings of the WoWMoM 2015: A World of Wireless Mobile and Multimedia Networks, IEEE conference proceedings, 2015Konferensbidrag (Refereegranskat)
    Abstract [en]

    Empirical studies show that cruising for car parking accounts for a non-negligible amount of the daily traffic, especially in central areas of large cities. Therefore, mechanisms for minimizing traffic from cruising directly affect the dynamics of traffic congestions. One way to minimizing cruising traffic is efficient car-parking-slot assignment. Usually, the related design problems are combinatorial and the worst-case complexity of optimal methods grows exponentially with the problem sizes. As a result, almost all existing methods for parking slot assignment are simple and greedy approaches, where each car or the user is assigned a free parking slot, which is closer to its destination. Moreover, no emphasis is placed to optimize any form of fairness among the users as the a social benefit. In this paper, the fairness as a metric for modeling the aggregate social benefit of the users is considered. An algorithm based on Lagrange duality is developed for car-parking-slot assignment. Numerical results illustrate the performance of the proposed algorithm compared to the optimal assignment and a greedy method.

  • 31.
    Algers, Staffan
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Transportvetenskap, Transport- och lokaliseringsanalys. KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Centra, Centrum för transportstudier, CTS.
    Even more possibilities to combine demand models2011Konferensbidrag (Övrigt vetenskapligt)
  • 32.
    Algers, Staffan
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Transportvetenskap, Transport- och lokaliseringsanalys. KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Centra, Centrum för transportstudier, CTS.
    New models for high speed rail forecasting2011Konferensbidrag (Övrigt vetenskapligt)
  • 33.
    Algers, Staffan
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Transporter och samhällsekonomi, Transport och lokaliseringsanalys. KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Centra, Centrum för transportstudier, CTS.
    What is the monetary value of security?2010Konferensbidrag (Övrigt vetenskapligt)
  • 34.
    Algers, Staffan
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Centra, Centrum för transportstudier, CTS. KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Transportvetenskap, Transport- och lokaliseringsanalys.
    Beser Hugosson, Muriel
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Centra, Centrum för transportstudier, CTS. KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Transportvetenskap, Transport- och lokaliseringsanalys.
    Modelling choice of flight and booking class - a study using Stated Preference and Revealed Preference data2001Ingår i: International Journal of Services Technology and Management, Vol. 2, nr 1/2Artikel i tidskrift (Refereegranskat)
  • 35.
    Algers, Staffan
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Transporter och samhällsekonomi, Transport och lokaliseringsanalys.
    Eliasson, Jonas
    Mattsson, Lars-Göran
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Transporter och samhällsekonomi, Transport och lokaliseringsanalys.
    Is it time to use activity-based urban transport models? A discussion of planning needs and modelling possibilities2005Ingår i: The annals of regional science, ISSN 0570-1864, E-ISSN 1432-0592, Vol. 39, nr 4, s. 767-789Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    For some decades now, transport researchers have put considerable efforts into developing what is called activity-based approaches for modelling urban travel demand. The basic idea is that travel demand is derived from people's desires to take part in different activities. In particular, the interrelationships among different activities with respect to temporal and spatial constraints are in focus. It means that such models treat the activities and the travelling of the households with respect to where and when the activities can be carried out and how they may be scheduled, given characteristics of the households and potential opportunities, the transport networks and various institutional constraints. We discuss what demands we see on future travel demand models, with a focus on urban analysis. This discussion is somewhat biased towards what role activity-based models could play in meeting these demands. We then review in some detail three prominent and distinctly different representatives of operational activity-based models to give an indication of what new modelling possibilities they offer. Theoretical appeal, empirical validity, usefulness for planning, need for data and easiness of implementation are discussed. In the final section we draw some conclusions about the prospects of these models and of their descendants.

  • 36.
    Algers, Staffan
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Transporter och samhällsekonomi, Transport och lokaliseringsanalys. KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Centra, Centrum för transportstudier, CTS.
    Mattsson, Lars-Göran
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Transporter och samhällsekonomi, Transport och lokaliseringsanalys. KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Centra, Centrum för transportstudier, CTS.
    Rydergren, Clas
    Östlund, Bo
    Sampers: erfarenheter och utvecklingsmöjligheter på kort och lång sikt2009Rapport (Övrigt vetenskapligt)
  • 37.
    Algers, Staffan
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Transportvetenskap, Transport- och lokaliseringsanalys.
    Petz, M.
    Embedded parks in Quiet Zones2012Ingår i: 41st International Congress and Exposition on Noise Control Engineering 2012, INTER-NOISE 2012: Volume 4, 2012, 2012, s. 3024-3035Konferensbidrag (Refereegranskat)
    Abstract [en]

    One of the targets of the European project "CityHush Acoustically Green Road Vehicles and City Areas" under the 7th Framework Program is to support city administrations to eliminate harmful effects of noise exposure and decrease levels of transport noise, especially in urban areas. A particular attention has been paid to investigating boundary conditions and maximum noise gains especially for parks embedded in Q-zones where only quiet low emission vehicles are tolerated. Other vehicles are banned or subject to a noise fee for entering the quiet zone. Within the CityHush project existing noise levels in different parks of European cities were determined and the influence of local parameters on the noise situation, such as size of a Qzone, was investigated. Moreover a variation of noise fees and traffic restrictions as well as different percentages of low noise vehicle ownerships inside the Q-zone and outside (countrywide) was evaluated. Based on different noise and annoyance criteria possibilities and limits to reduce noise in the city environment will be shown, based on studies carried out for 5 European cities.

  • 38. Alhasan, Ilyas
    et al.
    Matthews, Brian
    Towner, Jeremy
    Susilo, Yusak
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Systemanalys och ekonomi.
    Evaluation of intercounty integrated ticketing scheme, the case of Movingo in Sweden2019Konferensbidrag (Refereegranskat)
  • 39.
    Alhassan, Ilyas B.
    et al.
    Institute for Transport Studies (ITS), University of Leeds, Leeds, LS2 9JT, United Kingdom.
    Matthews, Bryan
    Institute for Transport Studies (ITS), University of Leeds, Leeds, LS2 9JT, United Kingdom.
    Toner, Jeremy P.
    Institute for Transport Studies (ITS), University of Leeds, Leeds, LS2 9JT, United Kingdom.
    Susilo, Yusak
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Systemanalys och ekonomi. KTH, Skolan för industriell teknik och management (ITM), Centra, Integrated Transport Research Lab, ITRL. Institute for Transport Studies, University of Natural Resources and Life Sciences, Peter Jordan St. 82, Vienna, 1190, Austria.
    Revisiting public transport service delivery: Exploring rail commuters’ attitudes towards fare collection and verification systems2019Ingår i: European Journal of Transport and Infrastructure Research, ISSN 1567-7133, E-ISSN 1567-7141, Vol. 19, nr 4, s. 310-331Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Making Public Transport services more attractive and effective requires attractive and effective ticketing. This requires a clear understanding of user attitudes, needs and expectations. This study explored commuters’ attitudes to fare collection and verification and the underlying factors, their acceptance of the policy of “No-ticket-purchase on-board” and their preferences for fare verification options. Commuters rated their agreement with 17 ticketing related statements in a cross-sectional questionnaire survey conducted along the corridor with the largest proportion of cross-county commuting in Sweden, Stockholm – Uppsala. Four sets of hypotheses were then tested. The average scores were normally distributed and hence analysed using a two-way ANOVA. A One-way chi-square test was conducted to determine the commuters’ preference for fare verification approach. A t-test was used to analyse the perceived quality of ticketing and the commuters’ reaction to the policy of “No-ticket-purchase on-board PT vehicle”. Whilst the results showed that the commuters were relatively uniform in their attitudes, income, commuting route, ticket type and ticket purchase channel affected their attitudes. They were neutral to the policy of “No-ticket-purchase on-board”. Their attitude to fare collection was more positive than that of fare verification and they showed a preference for automatic fare verification. The study highlights a number of policy implications and recommends further research on the feasibility of passive fare verification and on commuters’ preferred options for fare verification.

  • 40.
    Ali, Taha
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Transportplanering.
    Analysis of traveler’s behaviorusing electric scooters based on surveys2021Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    I denna studie analyseras resebeteendet för användarna av E-scooter baserat på enkätfrågor. Huvudsyftet med studien är att förstå E-scooters användares natur och deras preferenser samt att analysera deras tripparametrar. Undersökningen var utformad för att täcka de flesta av debeteendemässiga inflytelserika faktorerna. Att representera motiv och barriärer mot e-scooteradoption i större Stockholm. den delades in i demografisk data, allmänna resepreferenser, val av E-scooter-val, parametrar för sista resan och allmänna diskussionsfrågor. Resultaten av denna studie föreslog att E-skotrar huvudsakligen används av invånare i åldrarna 18-24. I Stockholm är anläggningar för kollektivtrafik mycket tillgängliga och prisvärda än andra privata transportsätt. Restid och resekostnader utvärderades mycket av användarna och ansågs vara avgörande kriterier innan de gjorde en resa i Stockholm. Resultaten föreslog att resor med e-skotrar främst är för skoj och fritid snarare än pendling och tjänster. När det gäller normala resor fann man dock att promenader ersatte användningen av E-skotrar oftare. Historiska data användes för att validera och stödja undersökningsresultaten.

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  • 41. Allström, A.
    et al.
    Kristoffersson, Ida
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Centra, Centrum för transportstudier, CTS. cVTI Swedish National Road and Transport Research Institute, Sweden.
    Susilo, Yusak
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Transportvetenskap, Systemanalys och ekonomi.
    Smartphone based travel diary collection: Experiences from a field trial in Stockholm2017Ingår i: Emerging technologies and models for transport and mobility 44th European Transport Conference Selected Proceedings, Casa Convalescència, Barcelona, Spain, 5-7 October 2016, Elsevier, 2017, Vol. 26, s. 32-38Konferensbidrag (Refereegranskat)
    Abstract [en]

    Currently, there is a great need for new methods to collect travel data. Traditional methods have considerable drawbacks and, at the same time, the models used to analyse the transport system require more and more detailed and high-quality data. An alternative method that stands out as very promising is to capture raw data from devices that can use any positioning technology (e.g., GPS, WiFi positioning, GSM, etc.), followed by transforming the raw data into meaningful travel data. Since most smartphones are equipped with various sensors that can be used to determine the location of the smartphone, and since smartphones are integrated in the daily life of most people, they provide an unprecedented opportunity for large-scale travel data collection. This method has a great potential to solve the problems related to the estimation of distance/travel time, geographic coding of departure/destination locations and forgotten trips and it will also provide a more detailed and extensive data set. In a recently completed research project the feasibility of replacing or complementing the traditional travel diary, with a suite of tools that make use of smartphone collected travel data has been evaluated. The advantages and disadvantages of the traditional method and the proposed method were studied. For a fair comparison, both methods have been tested in the same city, at the same time, and with the same respondents. To achieve the objectives of the project, MEILI, a system that consists of a smartphone application for capturing the movement of users and a web application for allowing the users to annotate their movement, has been deployed. The recruitment of respondents is a critical phase for traditional travel diaries and, as expected, this was the case also for the smartphone based method. A lesson learnt was that it is important to simplify the registration process as much as possible. In total 2142 trips were collected and annotated by 171 users. 51 of the users annotated trips covering more than a week. The experiences from the field trial shows that a smartphone based travel diary collection is a very useful complement to traditional travel diary collection methods since it appeals to a different age group and collects more detailed travel data for a longer period. The main findings of the paper are that smartphone based data collection is feasible, that the algorithms to save battery work well and that trips of the same respondent vary considerably depending on day of the week.

  • 42. Allström, Andreas
    et al.
    Rahmani, Mahmood
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Transportvetenskap, Trafik och logistik.
    Koutsopoulos, Haris
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Transportvetenskap, Trafik och logistik.
    Gundlegård, David
    Archer, Jeffery
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Transportvetenskap, Trafik och logistik.
    Mobile Millennium Stockholm2011Ingår i: Proceedings of the 2nd International Conference on Models and Technologies for ITS, 2011Konferensbidrag (Refereegranskat)
  • 43.
    Almlöf, Erik
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion.
    Beyond Technology: Understanding societal impacts of implementing self-driving vehicle systems on road transport2024Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [sv]

    Självkörande fordon har framställts som en viktig pusselbit för att uppnå hållbara och säkra resor, med möjligheter att förbättra trafikflödet, minska utsläppen och öka trafiksäkerheten. Det har dock visat sig att introduktionen av denna nya teknik inte var så enkel som det till en början framställdes, och att effekterna inte nödvändigtvis bara är positiva.

    I denna avhandling undersöker jag de samhälleliga effekterna av att införa självkörande fordon, uppdelat i fyra områden: varför forskning sker på området, hur de skulle realiseras, de samhälleliga effekterna av ett införande, samt relationen mellan självkörande fordon och hållbarhet.

    Jag visar att motiveringen för att göra forskning på området ofta är oklar och att själva existensen av forskning på området används för att självrättfärdiga mer forskning.

    Den mesta forskningen om att realisera självkörande fordon fokuserar på rent tekniska aspekter, såsom bättre algoritmer. Även om många utmaningar kvarstår på det området visar jag även att många andra praktiska problem kvarstår, kopplade till den sociotekniska kopplingen mellan teknik och samhälle. Till exempel saknas lösningar för hur fordonen skulle interagera med fotgängare, och de självkörande fordonen skulle dessutom behöva organiseras praktiskt på något sätt.

    Effekterna av självkörande teknik skulle även påverka många delar av samhället såsom framkomlighet, tillgänglighet och ekonomi. Därutöver demonstrerar jag att inget nuvarande ramverk för att förstå samhällseffekter lyckas fånga samtliga aspekter, och att effekterna skulle variera med hänsyn till t ex geografi.

    Dessa samhällseffekter får även påverkan på hållbarhet, där nya utmaningar kan uppstå. Jag visar att nuvarande styrmedel för transportsystemet fortfarande är relevanta, men att en helhetssyn krävs för att effektivt hantera utmaningarna. 

    Avslutningsvis efterlyser jag en nyanserad bild av självkörande fordon. Att introducera en ny teknik kräver rigorös och framåtsyftande planering och styrning för att säkerställa att självkörande fordon uppnår övergripande hållbarhetsmål och leder till att berika människors liv.

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  • 44.
    Almlöf, Erik
    KTH, Skolan för industriell teknik och management (ITM), Centra, Integrated Transport Research Lab, ITRL.
    Exploring societal impacts of self-driving public transport using four-step transport models2022Licentiatavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [sv]

    Självkörande teknik har under det senast decenniet synts allt mer i media, med målet att människor ska slippa köra själv på väg till jobbet, och istället kunna vila, läsa tidningen eller hålla ett möte. Dessa visioner har dock i huvudsak fokuserat på just bilen, trots att kollektivtrafiken skulle kunna dra stor nytta av självkörande teknik. För busstrafik står bussföraren för hälften av kostnaden för att köra trafiken, och besparingar på personalkostnader skulle t ex kunna återinvesteras i mer utökad kollektivtrafik, lägre skatter eller utökad välfärd inom andra områden.

    Samtidigt så har alltmer forskning visat på potentiella problem kopplat till självkörande teknik, exempelvis att den mer bekväma körningen skulle leda till mer trafik som i sin tur leder till mer utsläpp, höjda bullernivåer i städer eller ytterligare fokus på bilcentrerad infrastruktur. För kollektivtrafiken har även förarens roll som trygghetsskapande och som problemlösare lyfts fram – vem ska jag fråga om vägen om det inte finns en kunnig förare ombord? 

    Olika metoder har tidigare använts för att utforska samhällseffekterna av självkörande teknik, i den här avhandlingen har jag använt mig av så kallade ”fyrstegsmodeller”, mer specifikt den svenska transportmodellen Sampers. Fyrstegsmodeller har använts i uppemot 50 år för att utvärdera effekter på transportsystemet, men har ställts inför nya krav på att hantera fordon som körs av sig själva. Inom min forskning har jag gjort anpassningar av modellen för att simulera självkörande teknik och undersökt vilka effekter detta får på t ex trafikvolymer och utsläpp.

    I de tre vetenskapliga artiklarna som är del av avhandlingen har jag kommit fram till fyra huvudsakliga slutsatser:

    • Självkörande teknik kan innebära stora besparingar i kostnader för kollektivtrafiken, i första hand för busstrafik men även i viss mån för spårtrafik. Därutöver skulle en mer jämn körstil innebära bekvämare resor, vilket skulle öka kollektivtrafikens attraktionskraft. Därutöver kan kollektivtrafik som inte begränsas av t ex förarscheman eller nuvarande kommersiella villkor kunna innebära nya tjänster, såsom efterfrågestyrd (”on-demand”) kollektivtrafik. 
    • Fyrstegsmodeller har tidigare använts för att modellera transportsystemet och visat sig ha god överenstämmelse med verkligheten, åtminstone på övergripande nivå. Inom ramen för min forskning har jag gjort anpassningar av Sampers för att efterlikna självkörande teknik, men modellerna kan i sin nuvarande form inte ta hänsyn till t ex delande av fordon. 
    • Det är viktigt att påpeka att förare idag utför många uppgifter som inte direkt är kopplade till framförandet av fordonet, såsom att svara på frågor, upprätthålla ordning bland resenärer och att ta hand om fel som uppstår på fordonet. Dessa roller kan självkörande teknik idag inte uppfylla. 
    • De samhällseffekter som identifierats är överlag varierande och mångfaldiga. Självkörande teknik för kollektivtrafik skulle påverka människors tillgänglighet, körstilen för fordonen, tryggheten ombord, hur vi planerar trafiken och de personer som idag arbetar som förare. Dessutom är effekterna generellt sett inte likartade över geografi, tidsenhet eller för olika aktörer, vilket ytterligare understryker att effekten inte är enkel att sammanfatta. 
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  • 45.
    Almlöf, Erik
    KTH, Skolan för industriell teknik och management (ITM), Centra, Integrated Transport Research Lab, ITRL.
    Jenelius, Erik (Medarbetare/bidragsgivare)
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Transportplanering.
    PSSST – Policies for sustainable, shared and self-drivingtransportation2022Rapport (Övrig (populärvetenskap, debatt, mm))
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  • 46.
    Almlöf, Erik
    KTH, Skolan för industriell teknik och management (ITM), Centra, Integrated Transport Research Lab, ITRL.
    Acosta Carrascal, Henry (Författare till förord, introducerande material, etc.)
    KTH, Skolan för industriell teknik och management (ITM), Centra, Integrated Transport Research Lab, ITRL.
    Results for the comparison between e-scooter trips and their public transport and walking equivalent in the city of Gothenburg2023Rapport (Övrig (populärvetenskap, debatt, mm))
    Abstract [en]

    This project examined shared e-scooter trips provided by the operator Voi and used a trip planner to determine the potential alternatives if users had chosen to walk or utilise public transportation (PT) instead.

     

    The analysis reveals that Voi trips are typically brief, with 71% lasting less than 10 minutes, usually covering 1-2 kilometres, and mostly occurring within central Gothenburg. The trip planner indicated that walking would be the best alternative for roughly half of the trips, while public transportation would be the main alternative for the other half. 

     

    For the trips for which the trip planner suggested walking as the best alternative, 81% of them are less than 1 km long, meaning they could be alternatively covered by walking 15 minutes or less. Nonetheless, 89% of trips are faster with Voi, and 72% of them begin or end within 100 metres of a public transport stop, which strongly implies intermodal behaviour among e-scooter users and the use of e-scooters as a first/last mile solution; however, further research is necessary to support this statement.

     

    Regarding the trips for which the trip planner suggested PT with no transfers, half of the users would have had to walk 500 m or more to access and egress PT and 80% of them started or ended within 100 m of a public transport stop, which can suggest users choosing Voi to replace a leg of their trips; or even the complete trip, considering that roughly half of these trips would have been theoretically cheaper with Voi instead of PT. Nonetheless, once again, more research is needed to support these hypotheses.

     

    Generally, shared e-scooters hold the potential to complement public transportation services in densely populated urban areas, a notion supported by this study and prior academic and grey research. Even in the absence of parking regulations, users tend to initiate or conclude their trips near public transport stops, which can serve as a valuable guideline for developing parking policy.

     

    In conclusion, shared e-scooters represent an important aspect of urban transportation that should not be overlooked. It is crucial to engage both existing and potential e-scooter operators in transportation planning to foster collaboration with municipalities, PT agencies and local communities. This collaborative effort should aim to promote multimodality, integrated ticketing solutions, and user-centric approaches that encourage a shift away from less sustainable transportation modes.

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  • 47.
    Almlöf, Erik
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Centra, Integrated Transport Research Lab, ITRL.
    Hesselgren, Mia
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion (Inst.), Produkt- och tjänstedesign.
    From technological fixes to societal solutions: A sociotechnical framework for understanding self-driving technology implementation2024Manuskript (preprint) (Övrigt vetenskapligt)
    Abstract [en]

    Self-driving vehicles have been hailed as a revolutionary force that will benefit society through increased accessibility and reduced accident rates. However, implementing such a new technological system will be complex, requiring immense societal adaptions and changes. In this paper, we analyse the challenges faced in implementing self-driving vehicles based on interviews with onboard operators and stakeholders responsible for the operations of self-driving buses in northwest Stockholm, Sweden. From these interviews, we suggest a framework for understanding which societal changes would be required to implement self-driving vehicles.

    We highlight the complexities of self-driving and the sociotechnical perspective needed to understand the challenges of implementing self-driving vehicles, underscoring human drivers' complex and tacit knowledge. Further, we identify a crucial technological gap in the vehicles' understanding of context, suggesting that comprehensive self-driving operation requires a form of general intelligence beyond the current, specialised, driving-only intelligence. The findings presented in this paper pave the way for further research and efforts needed to enable broader adoption of self-driving vehicles and offer insights for policymakers to guide future legislation in self-driving transport. 

    In conclusion, several adaptions are required to facilitate self-driving vehicles. However, policymakers are advised to uphold stringent transport requirements, regardless of human or machine drivers, and resist any pressures to unnecessarily relax regulations. Such a cautious approach will ensure the continued prioritisation of safety and efficacy without compromising the human norms and behaviours that are integral and necessary to transport systems. 

  • 48.
    Almlöf, Erik
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Centra, Integrated Transport Research Lab, ITRL. Region Stockholm.
    Nybacka, Mikael
    Pernestål Brenden, Anna
    KTH, Skolan för industriell teknik och management (ITM), Centra, Integrated Transport Research Lab, ITRL.
    Will public transport be relevant in a self-driving future? A demand model simulation of four scenarios for Stockholm, Sweden2020Ingår i: Transportation Research Procedia 49, Association for European Transport , 2020, Vol. 49, s. 60-69Konferensbidrag (Refereegranskat)
    Abstract [en]

    The public sector makes long-term investments in for example tram rail lines and highways based on forecasts of future travelling but generally do not consider the impacts of self-driving technology as a factor. Several papers have presented transport system wide simulations with self-driving cars, exploring changes in mode choice, energy demand or the potential for sharing. Demand traffic models have been used in several studies, looking at modal choice changes, but the general assumption is that the public transport service remains unchanged, despite a large potential for governments to enhance service or reduce costs. This paper examines the effects of self-driving technology on the transport system with Stockholm, Sweden as a case study, looking at four scenarios which were developed with input from 130 transport professionals from industry, academia and the public sector. Each of the scenarios include one "car" and one "public transport" mode, looking at changes in e.g. modal choice and person kilometers traveled. The national demand model Sampers is used for evaluation. The results indicate a decrease in walking and bicycling in all scenarios and a decrease in public transport travelling in scenarios with a taxi-like car service. Although this result would mean a shift from public transport to car travel, the majority of travel to and from central parts of Stockholm were still made by public transport.

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  • 49.
    Almlöf, Erik
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Centra, Integrated Transport Research Lab, ITRL.
    Nybacka, Mikael
    KTH, Skolan för teknikvetenskap (SCI), Teknisk mekanik.
    Pernestål Brenden, Anna
    KTH, Skolan för industriell teknik och management (ITM), Centra, Integrated Transport Research Lab, ITRL.
    Jenelius, Erik
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Centra, Centrum för transportstudier, CTS. KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Transportplanering.
    Will leisure trips be more affected than work trips by autonomous technology? Modelling self-driving public transport and cars in Stockholm, SwedenManuskript (preprint) (Övrigt vetenskapligt)
    Abstract [en]

    Self-driving technology may lead to a paradigm shift for the transport industry with shared cars available to everyone. However, this vision has increasingly been challenged as too optimistic and unsubstantiated. In this study we explore societal impacts of using this technology for both cars and public transport and investigate differences depending on geography and trip purpose. Four scenarios were designed through workshops with 130 transport experts, modelled using a conventional four-step model for Stockholm, Sweden and evaluated in terms of changes to mode choice, number of trips and person kilometres. 

    We find larger increases for non-commuting trips, i.e. service and leisure trips, than for commuting trips, questioning the view of the ‘productive work trip’ as self-driving technology’s main impact on society. As these trips are primarily made outside of rush hours, this may lead to a changed transport system. Geographic differences are substantial and heavily dependent on the cost model for car alternatives, even indicating a reduction in car travel in rural areas if private ownership would be replaced by shared cars. Furthermore, walking and cycling levels decreased in all scenarios while enhancing public transport using self-driving technology has a limited impact on ridership. 

    These results show that the impacts of self-driving technology may have varied societal impacts even within a region and may lead to increased car travel, especially off-peak. These conclusions stress the need for policies that are sensitive to both geography and time. 

  • 50.
    Almlöf, Erik
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Centra, Integrated Transport Research Lab, ITRL.
    Rubensson, Isak
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö.
    Cebecauer, Matej
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Transportplanering.
    Jenelius, Erik
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Transportplanering. KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Centra, Centrum för transportstudier, CTS.
    Who is still travelling by public transport during COVID-19?: Socioeconomic factors explaining travel behaviour in Stockholm based on smart card data2021Konferensbidrag (Refereegranskat)
    Abstract [en]

    The COVID-19 pandemic has changed travel behaviour and reduced the use of public transport throughout the world, but the reduction has not been uniform. In this study we analyse the propensity to stop travelling by public transport during COVID-19 for the holders of 1.8 million smart cards in Stockholm, Sweden. We suggest two models for explaining the change in travel pattern, linking socioeconomic data with the probability to stop travelling. We find that education level, income and age are strong predictors, but that workplace type also substantially affect the propensity of public transport travel. Furthermore, we use clustering to divide the population into five separate social groups, serving as a more intuitive understanding of how the pandemic has affected different citizens’ propensity to use public transport. The results can guide policy makers on how to better tail e.g. bus supply to local demand, either through an increased understanding of differences based on the results or by further incorporating the results into a transport simulation models.

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