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.

This paper examines how Sweden and the United States have been impacted by philanthropicactivities, commercialization of university-based knowledge and internationalentrepreneurship. The analysis comprises a detailed case study of Swedish and U.S.universities, as well as a statistical analysis of the impact of philanthropy on economicgrowth. The results show that the United States has prompted a university system based oncompetition and variety, with an emphasis on philanthropy, promoting knowledge creation.International entrepreneurship has been an important mechanism by which this knowledge isglobalized leading to increased economic growth. Conversely, Swedish universities werecharacterized by less commercialized R&D and weak links to the commercial sector, rootedtraditionally in dependence on tax-financed and homogenous university structure. TheSwedish model has begun to change with important implications for development in smallerdomestic markets. The analysis has important implications for knowledge creation as asource of economic growth through international entrepreneurship taking advantage ofglobalization, especially for smaller countries.

Internal combustion engines waste a large amount of fuel energy through their exhausts. Various technologies have been developed for waste heat recovery such as turbocompounds, Rankine bottoming cycles, and thermoelectric generators that reduce fuel consumption and CO2 emissions. Turbocompounding is still not widely applied to vehicular use despite the improved fuel economy, lower cost, volume, and complexity higher exhaust gas recirculation driving capability and improved transient response. This paper comprehensively reviews the latest developments and research on turbocompounding to discover important variables and provide insights into the implementation of a high-efficiency turbocompound engine. Attention should be paid to the optimization of turbocompound engines and their configurations because the major drawback of this technology is additional exhaust back-pressure, which leads to higher pumping loss in the engines. Applying different technologies and concepts on turbocompound engines makes the exhaust energy recovery more efficient and provides more freedom in the design and optimization of the engines. Turbine efficiency plays an important role in the recovery of the wasted heat so turbine design is a crucial issue in turbocompounding. In addition, variability in geometry and rotational speed of power turbines allows for more efficient turbocompound engines in different operating conditions. The conclusion drawn from this review is that turbocompounding is a promising technology for reducing fuel consumption in the coming decades in both light- and heavy-duty engines.

To decrease the influence of the increased exhaust pressure of a turbocompound engine, a new architecture is developed by combining the turbocompound engine with divided exhaust period (DEP). The aim of this study is to utilize the earlier stage (blowdown) of the exhaust stroke in the turbine(s) and let the later stage (scavenging) of the exhaust stroke bypass the turbine(s). To decouple the blowdown phase from the scavenging phase, the exhaust flow is divided between two different exhaust manifolds with different valve timing. A variable valve train system is assumed to enable optimization at different load points. The fuel-saving potential of this architecture have been theoretically investigated by examining different parameters such as turbine flow capacity, blowdown valve timing and scavenging valve timing. Many combinations of these parameters are considered in the optimization of the engine for different engine loads and speeds.

This architecture produces less negative pumping work for the same engine load point due to lower exhaust back pressure; however, the exhaust mass flow into the turbine(s) is decreased. Therefore, there is a compromise between the turbine energy recovery and the pumping work. According to this study, this combination shows fuel-saving potential in low engine speeds and limitations at high engine speeds. This is mainly due to the choked flow in the exhaust valves because this approach is using only one of the two exhaust valves at a time. To reveal the full potential of this approach, increasing the effective flow area of the valves should be studied.

This paper presents a combination of theoretical and experimental investigations for determining the main heat fluxes within a turbocharger. These investigations consider several engine speeds and loads as well as different methods of conduction, convection, and radiation heat transfer on the turbocharger. A one-dimensional heat transfer model of the turbocharger has been developed in combination with simulation of a turbocharged engine that includes the heat transfer of the turbocharger. Both the heat transfer model and the simulation were validated against experimental measurements. Various methods were compared for calculating heat transfer from the external surfaces of the turbocharger, and one new method was suggested.

The effects of different heat transfer conditions were studied on the heat fluxes of the turbocharger using experimental techniques. The different heat transfer conditions on the turbocharger created dissimilar temperature gradients across the turbocharger. The results show that changing the convection heat transfer condition around the turbocharger affects the heat fluxes more noticeably than changing the radiation and conduction heat transfer conditions. Moreover, the internal heat transfers from the turbine to the bearing housing and from the bearing housing to the compressor are significant, but there is an order of magnitude difference between these heat transfer rates.

Current digitalized manufacturing systems do not yet achieve the goal of smart manufacturing: precise con-trol and agility under unexpected disruptions. Push-Pull Digital Thread is a solution concept to enable contex-tual data and knowledge exchange across operational and functional units in a manufacturing enterprise. The extraction of decision reasoning and functional information can be facilitated by Large Language Models proc-essing information obtained from a decision maker at the point of decision. This concept shows a potential to address critical limitations in previous endeavours for smart manufacturing systems by building a semanti-cally searchable and sharable knowledge base in manufacturing systems and beyond.

The aim of thiswork is to study sound generating flowstructures in a thickcircular orifice plate jet, placed in a circular duct. Large eddy simulations (LES)are performed for two jet Mach numbers, 0.4 and 0.9. Characteristic frequenciesin the flow, and their corresponding flow structures, are identified with dynamicmode decomposition (DMD). The results show that a tonal noise is generated atfrequencies where the jet displays strong ring vortices, in the plane wave range.The main sound generating mechanisms seems to be a fluctuating mass flow at theorifice opening and a fluctuating surface force at the plate sides, caused by the ringvortices. The frequencies are believed to be chosen, and strengthened, by a feedbackmechanism between the orifice in- and outlet.

The scattering of plane waves by an orifice plate with a strong bias flow, placed in a circular or square duct, is studied through large eddy simulations and dynamic mode decomposition. The acoustic-flow interaction is illustrated, showing that incoming sound waves at a Strouhal number of 0.43 trigger a strong axisymmetric flow structure in the orifice in the square duct, and interact with a self-sustained axisymmetric oscillation in the circular duct orifice. These structures then generate a strong sound, increasing the acoustic energy at the frequency of the incoming wave. The structure triggered in the square duct is weaker than that present in the circular duct, but stronger than structures triggered by waves at other frequencies. Comparing the scattering matrix with measurements, there is a good agreement. However, the results are found to be sensitive to the inflow, where the self-sustained oscillation in the circular duct simulation is an artefact of an axisymmetric, undisturbed inflow. This illustrates a problem with using an undisturbed inflow for studying vortex-sound effects, and can be of interest when considering musical instruments, where the aim is to get maximum amplification of specific tones. Further, it illustrates that at the frequency where an amplification of acoustic energy is found for the orifice plate, the flow has a natural instability, which is suppressed by non-axisymmetry and incoming disturbances.

Liner scattering of low frequency waves by an orifice plate has been studied using Large Eddy Simulation and an acoustic two-port model. The results have been compared to measurements with good agreement for waves coming from the downstream side. For waves coming from the upstream side the reflection is over-predicted, indicating that not enough of the acoustic energy is converted to vorticity at the upstream edge of the plate. Furthermore, the sensitivity to the amplitude of the acoustic waves has been studied, showing difficulties to simultaneously keep the amplitude low enough for linearity and high enough to suppress flow noise with the relatively short times series available in LES.

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.

The need for improved public transport (PT) ticketing in ever-growing deregulated PT markets has made well-designed integrated ticketing systems a priority area of intervention for PT service providers around the world. Yet, very little practical evidence of its impacts are reported in Sweden and in the world at large. The focus of this study was the impacts of the Movingo integrated ticketing scheme in terms of PT patronage, user satisfaction and the perceived quality of the ticketing set-up. Three travel surveys were conducted along the Stockholm-Uppsala route. Methods including logistic regression and correlated t-tests were used to analyse the samples. The findings suggest that the scheme made rail commuting more attractive resulting in an overall increase of about 24% in ticket sales with 3%–15% car commuters reporting that they patronised PT services after the project. The scheme also resulted in increased rail commuter satisfaction. The overall perceived quality of the ticketing set-up did not however improve due to interoperability challenges. Service providers’ uncertainty about equitable distribution of revenue among the participating service providers, interoperability challenges and the lack of interest among most of the participating service providers to sell Movingo tickets are some issues to be addressed.

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.

Baffle or split silencers are commonly used, e.g., in HVAC systems and as inlet/outlet silencers on gas turbines. Another application is to reduce noise from the cooling fan inlet for large IC-engines. A baffle silencer can be seen as a periodic arrangement of parallel rectangular absorbers which can be placed in a rectangular duct. The noise reduction afforded by parallel baffles depends not only on the physical properties of the lining, but also upon the angle of incidence of the sound waves impinging and the baffle length. In this paper the potential of using baffles made of Micro-Perforated Panels is investigated in particular with the cooling fan inlet application in mind. Theoretical models for the damping is derived and used to design optimum configurations. The models are based on the wave propagation in a periodic array of baffles so that only one period can be investigated in order to find the different modes. In particular the least attenuated mode is important to find in order to optimize the behavior. An important aspect is the inner structure of the MPP baffle, i.e., can it just be an empty air volume or to what extent must internal waves be prevented by putting in walls. From a stiffness point of view some inner walls might also be needed to avoid vibration problems. Due to these complexities the theoretical models are only presented for the simplest cases. In order to validate the models and to get a more complete test of different designs experiments were also carried out. During these experiments the effect of flow was also tested.

The aim of the work reported in this paper is to investigate the aerodynamic installation effects for a generic cooling fan system. This is done by treating the ducted fan as a multi-port source and performing a source characterization, i.e., determining the source strength and source reflection matrix. From the source strength, which represents the sound radiated by the fan in a reflexion free (infinite) duct, the effect of various inflow distortions can be studied. The work is part of the EU-project ECOQUEST where the data will be used to validate the acoustic prediction tools.

Automotive turbo compressors generate high frequency noise in the air intake system. This sound generation is of importance for the perceived sound quality of luxury cars and may need to be controlled by the use of silencers. The silencers usually contain resonators with slits, perforates and cavities. The purpose of the present work is to develop acoustic models for these resonators where relevant effects such as the effect of a realistic mean flow on losses and 3D effects are considered. An experimental campaign has been performed where the two-port matrices and transmission loss of sample resonators have been measured without flow and for two different mean flow speeds. Models for two resonators have been developed using 1D linear acoustic theory and a FEM code (COMSOL Multi-physics). For some resonators a separate linear 1D Matlab code has also been developed. Different models, from the literature, for including the effect of mean flow on the acoustic losses at slits and perforates have been implemented in the codes and compared to the experimental data. Correct modeling of acoustic losses for resonators with complicated geometry is important for the simulation and development of new and improved silencers, and the present work contributes to this understanding. The developed models give acceptable agreement with the measured results even with flow but can be improved for 3D FEM if correct CAD data is available. The 1D linear theory can be used for simple geometries and to get a general overview related to the resonance frequencies and damping level.

There is increased concern about the noise emission from cooling systems. This is mainly due to an increased need for cooling needs due to turbo-charging and EGR systems, which tend to increase the fan power and thereby the noise. An important issue in this context is the behavior of the heat-exchanger and its acoustic transmission and absorption properties. In this paper an acoustic model to evaluate such data for a common type of heat exchanger, the parallel plate type, is presented. The basic configuration is assumed to be a matrix of parallel, narrow channels. The developed model is based on a so called equivalent fluid for an anisotropic medium. It is mainly dependent on the heat exchanger geometry combined with the Kirchhoff model for thermo-viscous wave propagation in narrow tubes. The proposed model can be used to predict the sound transmission and absorption for an entire heat exchanger for incident plane waves. This model is validated by comparison with measurement results for seven different heat exchangers used in vehicle and train cooling units at different flow speeds

Splitter or baffle silencers are commonly used, for example, in heating ventilation and air conditioning (HVAC) systems and as inlet/outlet silencers on gas turbines. Another application is to reduce noise from the cooling fan inlet for large IC-engines. A splitter silencer can be seen as a periodic arrangement of parallel rectangular absorbers, which can be placed in a rectangular duct. The noise reduction afforded by parallel splitters depends not only on the physical properties of the lining but also upon the angle of incidence of the impinging sound waves, and the splitter and duct dimensions. In this paper, the potential of using splitters made of microperforated plates (MPPs) is investigated, with a particular focus on cooling fan inlet/outlet applications.

In this paper two different objects for fan passive noise control have been examined: heat exchangers and inlet/outlet parallel splitter silencers based on micro-perforated panels. The first object is theoretically and experimentally examined while the second is only examined experimentally. Throughout this paper two measurement methods were used. The ISO 15186-1:2000 to test the acoustic transmission for a diffuse field and plane wave testing in a duct of a sample cut from each heat exchanger type. Based on an anisotropic equivalent fluid model a theoretical model for the heat exchanger acoustic transmission is presented. A new type of splitter silencers based on micro-perforated plates, which can add damping up 10-20 dB in the frequency range of interest (<5 kHz), are also presented.

Automated driving systems (ADS) have gained sizable attention over the last decade, promising safer, cheaper, and more accessible transportation. However, the discourse driving this research has not been thoroughly explored, with scant qualitative work detailing specific cases. To address this gap, this paper explores the motivations for the societal need for ADS research for the 500 most cited publications in the field, investigating explicit motivations (e.g., accident reduction), writing style, assumed likelihood of outcomes, and the text's tone. Qualitative and quantitative techniques are used, as well as the tool ChatGPT to investigate the large number of texts. The results show that the most common motivation is the emergence itself (‘ADS are coming, so they need to be studied’), followed by potential benefits such as accident reduction, congestion mitigation, increased comfort and productivity onboard, and environmental concerns. The tone of the publications is primarily neutral or slightly positive but with some deterministic descriptions like ‘ADS will lead to’ rather than more cautious language like ‘can’ or ‘may’. The results offer a glimpse rather than a comprehensive overview of the discourse on ADS within the research community. While the analysis might not capture the nuanced perspectives that readers encounter in publications focused on 'impacts', the reviewed publications remain the most cited works in the field, likely affecting the discourse to some extent.

During the last decade, self-driving technology has become increasingly visible in the news, with the vision that people would enter vehicles that drive themselves, and that people could instead rest, read the newspaper, or have a meeting. However, these visions have mainly focused on the potential for car usage, even though public transport could benefit greatly from self-driving technology. For bus traffic, the bus driver accounts for half of the cost of driving, and savings on personnel costs could, for example, be reinvested in expanded public transport service or used to lower taxes.

At the same time, more research has shown potential problems linked to self-driving technology, for example that more comfortable driving would lead to more traffic, which in turn would lead to increased emissions, higher noise levels in cities or further focus on car-centric infrastructure. For public transport, the driver's role in creating safety and acting as problem solvers has also been emphasized - who should I ask for directions if there is no knowledgeable driver on board?

Various methods have previously been used to explore the social effects of self-driving technology and in this dissertation I have used so-called "four-stage models", more specifically the Swedish transport model Sampers. Four-stage models have been used for 50 years to evaluate effects on the transport system from e.g. infrastructure changes, but these models face new challenges, handling vehicles that drive by themselves. In my research, I have adjusted the model to simulate self-driving technology and investigated what effects this has on, for example, traffic volumes and emissions.

In the three articles that are part of the dissertation, I have four main conclusions:

• Self-driving technology can mean large savings in costs for public transport, primarily for bus traffic but also to some extent for rail traffic. In addition, a smoother driving behaviour would mean more comfortable travel, which would increase the attractiveness of public transport. In addition, public transport not limited by, for example, driver schedules or current commercial conditions, could develop new types of services, such as on-demand public transport.
• Four-stage models have previously been used to model the transport system and have been shown to have good results, at least at an overall level. Within my research, I have made some adaptations of these models to mimic self-driving technology, but the models in their current form cannot consider, for example, vehicle sharing.
• It is important to point out that bus and train drivers currently perform many tasks that are not directly related to the driving of the vehicle, such as answering questions, maintaining social order among passengers and taking care of faults that occur during the trip. Today, self-driving technology cannot fulfil these roles.
• Self-driving technology for public transport would affect people's accessibility, driving style for vehicles, safety on board, how we plan traffic and the people who currently work as drivers. In fact, a multitude of societal effects have been identified, affecting all areas of transport. In addition, the effects are generally not similar across geographies, time units or for different actors, which further emphasizes that the total effect is not easy to summarize.

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.

Föreliggande slutrapport är finansierad av Trafikverkets FoI portfölj, strategiska  initiativ,för projekt Självkörande eldriven stombuss på Tvärförbindelse Södertörn – En skalbarfallstudie (TRV 2019/118695). Partners i projektet är Trafikverket, Scania, Volvo, Keolis,KTH samt Sweco där även Trafikförvaltningen Region Stockholm, Nobina och projektTvärförbindelse Södertörn har bidragit till arbetet som pågått från maj 2020 till mars 2021.Ansvarig för projektet inom Trafikverket har varit Stora projekt.För att skapa en förståelse för konsekvenser av tekniska utveckling i relation tillnödvändiga fysiska och digitala åtgärder har tre scenarier tagits fram: Bus Driver Plus,Automation with Adaption och Automation Utopia. Dessa scenarier beskriver olika nivåerav automation och behov av kringliggande stödsystem. I det första scenario finns enförare ombord på bussen som tar över körningen vid farliga situationer. Det andrascenariot avser en självkörande buss utan förare där den fysiska infrastrukturen haranpassats genom ett införande av ett eget busskörfält. Det sista scenariot beskriver enframtid där bussen helt förlitar sig på digital teknik och en operatör kontrollerar körningenav flera fordon från ett avsides kontrolltorn.De tre scenarierna utvärderades genom en samlad effektbedömning, Trafikverkets metodför att utvärdera åtgärder. Resultaten visar att den största vinsten av automatisering kanhandla om resenärernas bekvämlighet och inte nödvändigtvis om att minimera kostnaderför förare. Antaganden om att resenärerna kan uppleva resan bekvämare är troligtvisöverskattade, men resultaten visar att även små förbättringar i bekvämlighet kan ge storasamhälleliga vinster.Scenariot där bussen har ett eget körfält innebär mycket stora kostnader och är troligtvisinte ekonomiskt försvarbart. Dessutom kommer enbart en busslinje att trafikeramotorleden som dessutom består av 3 tunnlar. Vidare är det inte säkert att den aktör somgör nödvändiga investeringar är den aktör som får ta del av de samhälleliga vinsterna. Iscenariot skulle Trafikverket stå för stora delar av investeringskostnaden, medan vinsten för personalbesparingar uppstår för Region Stockholm och kollektivtrafikresenärerna somåker längs sträckan.Projektet har även undersökt hur multimodala hubbar (nod som möjliggör smidigt bytemellan olika transportmedel) längs med förbindelsen kan stödja eldrivna och självkörandebussar. Det är viktigt att ny väginfrastruktur bidrar till en attraktiv kollektivtrafik därresenärer i första hand väljer buss istället för bil. För att eldrivna och självkörande bussarska införas behöver Region Stockholm ställa nya krav i upphandlingar för attåstadkomma en förändring i transportsystemet. Nya krav som skapar ekonomiskaincitament för operatörer som utför den operativa verksamheten över lång tid. Det är dockproblematiskt att ställa krav på eldrift eftersom det saknas tillgänglig infrastruktur iStockholm.Avseende självkörande fullängdsbussar är tekniken helt enkelt inte tillräckligt mogen idag.Dock tror många experter att självkörande bussar kommer att införas, både i stadsmiljöoch glesbygd, när tekniken och samhället är redo för det, gissningsvis kring år 2030.

Researchers struggle to create simple yet nuanced diagrams or short abstracts that are easily comprehendible by non-experts. Research articles may be our primary communication method, but they are generally difficult to understand, making them unsuitable for general communication. This paper investigates a rarely used method in transport research – vignettes – to convey research results and elicit implications for public planners. Historically, these vignettes have been designed using qualitative methods, e.g., the Delphi method or by researchers' review of trends. However, this paper uses two vignettes originating from quantitative results from a simulation model paper (Almlöf et al., 2022), investigating the impacts of self-driving technology. Rewriting the results into two short stories – vignettes – these stories then served as the starting point for semi-structured interviews and a workshop with six public officials in Stockholm, Sweden. The vignettes were used to understand what these results would mean to the participants and how they would combat potential problems connected to sustainability, given the vignettes. Finally, the interviews and the workshop were qualitatively analysed, and policy tools were identified that can steer the transport system towards societal goals. The vignettes were a powerful tool to help the participants envision a future with self-driving transport options and promote critical thinking regarding how each participant would be affected, given such a future. As such, vignettes should be further explored to help researchers investigate abstract subjects which participants may have difficulties understanding.

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. 

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.

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. 

Self-driving technology may lead to a paradigm shift for the transport industry with shared cars available to every-one. 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 had 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.

Introduction 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, for the spring and autumn of 2020. We suggest two binomial logit models for explaining the change in travel pattern, linking socioeconomic data per area and travel data with the probability to stop travelling. Modelled variables The first model investigates the impact of the socioeconomic factors: age; income; education level; gender; housing type; population density; country of origin; and employment level. The results show that decreases in public transport use are linked to all these factors. The second model groups the investigated areas into five distinct clusters based on the socioeconomic data, showing the impacts for different socioeconomic groups. During the autumn the differences between the groups diminished, and especially Cluster 1 (with the lowest education levels, lowest income and highest share of immigrants) reduced their public transport use to a similar level as the more affluent clusters. Results The results show that socioeconomic status affect the change in behaviour during the pandemic and that exposure to the virus is determined by citizens' socioeconomic class. Furthermore, the results can guide policy into tailoring public transport supply to where the need is, instead of assuming that e.g. crowding is equally distributed within the public transport system in the event of a pandemic.

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.

Numerous studies have studied the impacts of automated driving (AD) technology on e.g. accident rates or CO2 emissions using various frameworks. In this paper we present an overview of previous frameworks used for societal impacts and review their advantages and limitations. Additionally, we introduce the Total Impact Assessment (TIA) framework developed by the Swedish Transport Administration and use this framework to evaluate three scenarios for AD bus services in Stockholm. We conclude that the reviewed frameworks cover different aspects of AD technology, and that e.g. cybersecurity and biodiversity are areas largely neglected. Furthermore, most frameworks assume effects to be homogenous, when there may be large variation in e.g. perceived security. The TIA framework does not manage to include all societal aspects of AD technology, but has great benefits and manages to provide important insights of the societal impacts of AD technology, especially how effects may wary for different actors. 

Numerous studies have studied the impacts of self-driving technology on e.g. accident rates or CO2 emissions using various frameworks. In this paper we present an overview of previous frameworks used for societal impacts, and review their advantages and limitations. Additionally, we introduce the Total Impact Assessment (TIA) framework developed by the Swedish Transport Administration and use this framework to evaluate three scenarios for self-driving bus services in Stockholm. We conclude that the reviewed frameworks cover different aspects of self-driving technology, and that e.g. cybersecurity and biodiversity are areas neglected by most frameworks. Furthermore, most frameworks assume effects to be homogenous, when there may be large variation in e.g. perceived security. The TIA framework does not manage to include all societal aspects of self-driving technology, but has great benefits and manages to provide important insights of the societal impacts of self-driving technology, especially how effects may wary for different actors.

This paper analyzes how different R&D strategies of incumbent firms affect the quantity and quality of their entrepreneurial spawning. When examining entrepreneurial ventures of ex-employees of firms with different R&D strategies, three things emerge: First, firms with persistent R&D investments and a general superiority in sales, exports, productivity, profitability and wages are less likely to generate entrepreneurs than firms with temporary or no R&D investments. Second, start-ups from knowledge intensive business service (KIBS) firms with persistent R&D investments have a significantly increased probability of survival. No corresponding association between the R&D strategies of incumbents and survival of entrepreneurial spawns is found for incumbents in manufacturing sectors. Third, spin-outs from KIBS-firms are more likely to survive if they start in the same sector, indicating the importance of inherited knowledge. These findings suggest that R&D intensive firms are less likely to generate employee start-ups, but their entrepreneurial spawns tend to be of higher quality.

This paper develops a framework of innovation dynamics to appreciate observed heterogeneity of firm size distributions, in which dynamics refer to exit and entry of product varieties and variety markets of individual firms. The analysis is based on a model of variety-triplets where every such triplet in the economy is identified by a unique combination of a variety, destination and firm. New variety triplets are introduced by innovating firms in a quasi-temporal setting of monopolistic competition. Ideas for variety-triplets arrive to firms according to a firm-specific and state dependent Poisson process, whereas variety triplets exit according to a destination-specific Poisson process. The empirical analysis employs a detailed firm-level data base which provides information about all variety triplets. Firm size is measured by a firm's number of variety triplets. The empirical results are compatible with the model predictions of (i) a persistent distribution of firm sizes, (ii) frequent events of exit and entry, and (iii) state dependent entry, where a state may be given by each firm's composition of triplets and/or other firm attributes.

This paper focuses upon the ways in which characteristics of regions in regards to knowledge sources, communication opportunities, and absorptive capacity influence the development of innovation ideas among existing and potential entrepreneurs. We formulate a model where entrepreneurs or innovating firms introduce new products in a quasi-temporal setting. Market conditions are characterised by monopolistic competition between varieties belonging to the same product group, in which there is entry and exit of varieties. A stochastic process is assumed to generate new innovation ideas as time goes by, and a firm (entrepreneur) who receives such an idea has to transform the idea to an innovation, which in the model is specified as a particular variety combined with a specific destination market. The theoretical model is used as a reference when formulating two regression models, with which we estimate how a set of regional characteristics are associated with the likelihood of innovation ideas across Swedish local labour market regions. In one model, we examine the emergence of new export varieties, and in the second model, we investigate the appearance of new export firms. Results are consistent with the assumption that knowledge and information flows have a positive influence on the frequency of arrival of innovation ideas to firms.

This paper examines innovation among very small firms and provides new insights into both internal and external determinants of patenting. Applying a non-linear panel data approach to about 160,000 observations on manufacturing firms in Sweden for the period 2000-2006, the following facts emerge: (i) in contrast to larger firms, innovation in micro firms with 1-10 employees is not sensitive to variation in internal financial resources, (ii) skilled labour is even more important for innovation among micro firms compared to other firms, (iii) affiliation to a domestically owned multinational enterprise group increases the innovation capacity of small businesses, (iv) small firms' innovation is closely linked to participation in international trade and exports to the G7-countries, and (v) there is no statistically significant evidence that proximity to metropolitan areas, or presence in a specialized cluster, increases the innovativeness of the smallest firm.

Driverless multipurpose vehicles (DMVs) are an emerging vehicle concept for urban heavy-duty transport. However, little is known about their effect on urban road transport systems. Thus, the aim of this study is to analyse the total fleet energy consumption of DMVs for specific transport operations in urban logistics compared to heavy- duty battery and combustion vehicles. A novel electric vehicle routing problem was used to simulate in total 96 case-studies of operations with varying network and vehicle fleet properties. We found that the combustion vehicle fleets consumed significantly more energy for the same operation compared to the electric vehicle fleets. Although the DMV fleet and battery electric vehicle fleet showcased similar energy consumption for most case-studies, there were several operations where the DMV fleet consumed less energy and required a smaller fleet size. This study highlights the potential benefits of DMV fleets in urban logistics operations in terms of reducing total fleet energy consumption and fleet size.

Real vehicle usage rarely matches the predictions made during early phases of vehicle development and sales processes at commercial road vehicle manufacturers. The automotive industry needs multidisciplinary vehicle design methods to predict real-world vehicle operations by considering the vehicle level and the transport system level simultaneously, in a more holistic approach. The aim of this study was to analyse how realistic vehicle usage of driverless multipurpose vehicles can be modelled in Vehicle Routing Problems (VRPs) by conducting a systematic literature review. We found that real vehicle usage modelling of driverless multipurpose vehicles in VRPs mainly depended on the following elements: VRP variant, energy consumption model, energy consumption rate class, number of vehicle-specific design variables and transport system-level factors. Furthermore, we identified in the literature five classes of energy consumption rate edge behaviour in VRPs. These findings can support decision-making in the modelling process to select the most suitable combination of elements, and their level of detail for the overall modelling aim and purpose.

The urban logistics transport system brings a significant burden to cities, as the transport-related externalities (e.g., CO2 emissions, noise, and congestion) affect the liveability of the environment and the health of the citizens. To contrast these externalities, urban logistics concepts (e.g., logistics strategies, different vehicle types and vehicle technologies) are being developed and implemented. However, in the literature, there is a lack of a comparative evaluation of different concepts. This evaluation provides useful knowledge for both public and private decision-makers in the system. The goal of this research is to close the knowledge gap by analysing the sustainability performance of urban logistics concepts. Using an existing framework of key performance indicators (KPIs), this study aims to evaluate four urban logistics concepts (i.e., consolidation, electrification, cargo bikes and automation) based on their sustainability performance. The inputs to the framework are findings from the literature, regarding the impact of the concepts on the indicators. These findings can be both qualitative and quantitative. To collect these findings, we performed a literature review on relevant case and simulation studies. The output of the framework is a sustainability performance assessment of the concepts, visualized graphically. The results of this work enable stakeholders to understand how urban logistics concepts can be effective in achieving sustainability. This knowledge can help the decision-making process, favouring choices that promote a sustainable system. 

Road freight transport systems are complex socio-technical systems where freight services are provided through various technological solutions, with the involvement of several stakeholders. Despite the benefits of road freight transport to the economy and society, it also has substantial drawbacks for our current and future society, such as greenhouse gas emissions, congestion, air pollution, noise and poor working conditions. Therefore, several transport concepts and policies, such as electric vehicles and carbon taxes, are being explored and implemented within the private and public sectors to mitigate the externalities of road freight transport systems and achieve more sustainable systems.

Understanding sustainability transitions requires a holistic approach that includes multiple dimensions of sustainability and the perspectives of various stakeholders. Therefore, this thesis uses a System Thinking lens to achieve a system-level understanding of sustainability. Moreover, the dynamics and feedback structures of sustainability transitions are considered in order to identify leverage points and avoid policy resistance.

This thesis aims to understand the impacts of transport concepts and policies on the sustainability of road freight transport systems. A mixed-method approach, including surveys, interviews, and System Dynamics modelling is used to study the impacts of COVID-19 regulations, electric trucks, city hubs, cargo bikes, automation and off-peak hour deliveries. Moreover, policies impacting the adoption of electric trucks and city hubs are explored.

This thesis's results indicate that collaboration is required to achieve sustainability. However, collaboration is complex since stakeholders often have conflicting goals. Applying System Dynamics as a modelling method allows for understanding the right place and time to implement various policies. In this thesis, the simulation of different policy scenarios enables the consideration of the consequences of these policies from both short- and long-term perspectives. This knowledge benefits decision-makers in the private and public sectors in making decisions that shift road freight transport systems towards sustainability.

Using 530 responses from an online questionnaire, this study aims to investigate the transition from physical to online shopping alternatives during the first wave of the COVID-19 pandemic at the individual level. The focus areas of the study are Sweden and Italy, two European countries that implemented contrasting prevention measures. This study analyses the impacts of the pandemic on the transition to online shopping activities, and identifies who among the respondents changed their shopping behaviour the most and how; and what the different shopping strategies are and who adopted them. Multivariate statistical analyses, including linear and binary logistic regressions and multinomial logit models, were used to analyse the dataset. In the analysis, the dataset was split between Italy and Sweden to take into account the contrasting prevention measures and the different social and economic backgrounds of the two countries; the results of this study confirm and highlight these differences. Moreover, the socio-demographic and household structures of the respondents were found to influence the amount and the direction of change in shopping behaviour during the first wave of the pandemic. The study also indicates some policies that can be implemented and/or further strengthened to increase the resilience of citizens in facing pandemics and to derive benefit from the behavioural changes that took place during the first wave of the pandemic.

Through consolidation, city hubs offer potential solutions to sustainability challenges in urbanfreight systems. However, the viability of such hubs has been questioned, as the willingness topay of businesses receiving goods has been an issue. This study employs a system dynamicsapproach to explore this willingness to pay in consolidation initiatives by quantifying thebenefits receivers can gain, thus bridging a gap in the literature. The system dynamics methodallows a holistic view of the system. Therefore, a quantitative model is built to explore thebehaviour of the businesses receiving goods and their interests in value-added services. Datafrom a case study in Stockholm is used as quantitative input. Moreover, sixteen businesses inthe area are interviewed to understand their needs and to create different scenarios. The analysisof the interviews reveals that the level of interest in value-added services varies depending onthe type of business. Four types of receivers are identified: large offices, small offices, largeshops, and small shops. The model results show that the main benefits for the receivers are timesavings in handling deliveries, leading to cost savings and the use of the city hub for storage.The results of this research can be used by decision-makers in the private and public sectors tounderstand the dynamics of city hubs and to formulate effective policies for the success of thesehubs. The originality of this study lies in the combination of the system dynamic approach andthe receivers’ perspective, which is relatively underexplored. The results can thus providevaluable insights in achieving viable consolidation solutions.

Because many systems are evolving into cyberphysical systems, it is essential to examine their impact on society. This article introduces a multidisciplinary course that provides an overview of how these systems contribute to sociotechnical change.

The transport-related externalities of the urban logistics system impact the urban environment and the health of the citizens: there is a need to improve the sustainability of the system. In this paper, we use a framework for sustainability performance abessment and a literature review to analyse the urban logistics concepts of electrification, consolidation, cargo bikes and automation. In the literature, there is a focus on pollution, while a holistic perspective on sustainability is lacking. A Sustainability Performance Abessment (SPA) matrix is the main result of this paper, as a tool for comparing the concepts and understanding how they can be combined to achieve integrated benefits. To make informed decisions, stakeholders need knowledge from a holistic perspective. The findings presented in this paper are a first step to achieving this required knowledge.

The urban logistics system greatly affects the liveability of the urban environment and the health of citizens through transport-related externalities. Urban logistics practices are being implemented to contribute to the sustainability of the urban environment. To make informed decisions, actors and stakeholders require knowledge about these practices and their impacts. This paper proposes a set of measurable indicators for sustainability assessment. For assessing sustainability, it is key to comprehensively consider sustainability dimensions. Therefore, the starting point of this paper is the Sustainable Development Goals (SDGs), to have a holistic view of sustainability, combined with existing indicators in the city logistics literature, to ensure relevance to the context. Moreover, it is important to consider the perspective of different actors and stakeholders. The novelty of this work is the definition of indicators from the perspectives of both the citizens as stakeholders and the logistics service providers as actors. The set of indicators is tested in two previous studies, showing that it is possible to evaluate the sustainability performance of urban logistics practices. Future work includes using the set of indicators in a real case study, to test the attainability and relevance of the indicators. This set of indicators should be used to evaluate urban logistics practices, with the aim of increasing the knowledge that actors in the urban freight transport system have regarding these practices. This knowledge can help decision-makers in the private and public sectors to make decisions that facilitate a more sustainable urban freight transport system. 

This paper explores the system-level impacts of electrification on road freight transport efficiency, as a complex concept with involvement of various stakeholders. Introducing electrification adds further complexity, bringing in new stakeholders, dynamics, and efficiencies. The paper utilises system dynamics modelling to understand the dynamics between different efficiencies and the impact of electrification. The results of the simulation model highlight that there are trade-offs between different kinds of efficiencies, and it is essential to achieve a balance. Moreover, worse-before-better behaviour should be expected, as electrification initially increases costs but has lower costs in the long term. The results point to two phases of E-truck adoption: during the first phase, the policy focus should be on expanding charging infrastructure; during the second phase, cost-focused policies become critical to boosting electrification. By understanding the impact of different policies, this paper offers valuable knowledge to decision-makers navigating the transition towards a more sustainable system. 

The urban logistics system causes negative externalities, such as pollution, noise and congestion. This study focuses on city hubs as a concept to reduce these externalities by improving consolidation and adopting zero-emission vehicles. Our research employs system dynamics as a method to uncover the dynamics and mechanisms related to the barriers and potentials of city hub implementation in Stockholm from the perspectives of the Logistic Service Providers (LSPs), the receivers and the public sector. Moreover, a mixed method approach is used for data collection, allowing us to extract the knowledge from the real implementation case, co-create a qualitative model as a Causal Loop Diagram (CLD) with the stakeholders involved in the system, and generalise the model. The mixed method approach includes a group model-building workshop, literature review, existing city hub analysis and stakeholder interviews. The main result is a CLD, visualising the dynamics of the introduction of city hubs. The CLD explores three potential incentives and policies: (i) the receivers change address; (ii) shippers oblige LSPs to use the hubs; (iii) the public sector gives monetary incentives to LSPs. The CLD presented in this paper establishes a validated system structure for the urban logistic system and facilitates the policymakers' understanding of the barriers to implementing city hubs and what policies could help their implementation.