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  • 1.
    Ali, Raman
    Umeå University, Faculty of Science and Technology, Department of Mathematics and Mathematical Statistics.
    Root Cause Analysis for In-Transit Time Performance: Time Series Analysis for Inbound Quantity Received into Warehouse2021Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Cytiva is a global provider of technologies to global pharmaceutical companies and it is critical to ensure that Cytiva’s customers receive deliveries of products on-time. Cytiva’s products are shipped via road transportation within most parts of Europe and for the rest in the world air freight is used. The company is challenged to deliver products on time between regional distribution points and from manufacturing sites to its regional distribution centers. The time performance for the delivery of goods is today 79% compared to the company’s goal 95%.

    The goal of this work is to find the root causes and recommend improvement opportunities for the logistics organizations inbound in-transit time performance towards their target of 95% success rate of shipping in-transit times.

    Data for this work was collected from the company’s system to create visibility for the logistics specialists and to create a prediction that can be used for the warehouse in Rosersberg. Visibility was created by implementing various dashboards in the QlikSense program that can be used by the logistics group. The prediction models were built on Holt-Winters forecasting technique to be able to predict quantity, weight and volume of products, which arrive daily within five days and are enough to be implemented in the daily work. With the forecasting technique high accurate models were found for both the quantity and weight with accuracies of 96.02% and 92.23%, respectively. For the volume, however, too many outliers were replaced by the mean values and the accuracy of the model was 75.82%.

    However, large amounts of discrepancies have been found in the data which today has led to a large ongoing project to solve. This means that the models shown in this thesis cannot be completely reliable for the company to use when a lot of errors in their data have been found. The models may need to be adjusted when the quality of the data has increased. As of today the models can be used by having a glance upon.

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  • 2.
    Ali-Eldin, Ahmed
    et al.
    Chalmers University of Technology, Gothenburg, Sweden.
    Elmroth, Erik
    Umeå University, Faculty of Science and Technology, Department of Computing Science.
    Data management, communication systems and the edge: challenges for the future of transportation2021In: Communications in Transportation Research, E-ISSN 2772-4247, Vol. 1, article id 100024Article in journal (Other academic)
  • 3.
    Andersson, Dan
    et al.
    Research Unit for Movement, Health and Environment, Department of Physical Activity and Health, Swedish School of Sport and Health Sciences (GIH), Stockholm, Sweden.
    Wahlgren, Lina
    Research Unit for Movement, Health and Environment, Department of Physical Activity and Health, Swedish School of Sport and Health Sciences (GIH), Stockholm, Sweden.
    Olsson, Karin Sofia Elisabeth
    Research Unit for Movement, Health and Environment, Department of Physical Activity and Health, Swedish School of Sport and Health Sciences (GIH), Stockholm, Sweden.
    Schantz, Peter
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Section of Sustainable Health. Research Unit for Movement, Health and Environment, Department of Physical Activity and Health, Swedish School of Sport and Health Sciences (GIH), Stockholm, Sweden.
    Pedestrians' perceptions of motorized traffic variables in relation to appraisals of urban route environments2023In: International Journal of Environmental Research and Public Health, ISSN 1661-7827, E-ISSN 1660-4601, Vol. 20, no 4Article in journal (Refereed)
    Abstract [en]

    It is important to examine how motorized traffic variables affect pedestrians along a gradient from rural to inner urban settings. Relations between pedestrians' perceptions of four traffic variables and appraisals of route environments as hindering-stimulating for walking as well as unsafe-safe for reasons of traffic, were therefore studied in the inner urban area of Stockholm, Sweden (n = 294). The pedestrians rated their perceptions and appraisals with the Active Commuting Route Environment Scale (ACRES). Correlation, multiple regression, and mediation analyses were used to study the relationships between the traffic variables and the outcome variables. Noise related negatively to both hindering-stimulating for walking, and to unsafety-safety for traffic reasons. Vehicle speed related negatively to unsafety-safety for traffic reasons. Furthermore, vehicle speed protruded as an important origin of the deterring effects of traffic among those who commute by foot. The study shows the value of both partial and simultaneous analyses of the effect of all four traffic variables in relation to outcome variables relevant for walking.

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  • 4.
    Andersson, Dan
    et al.
    The Research Unit for Movement, Health and Environment, Department of Physical Activity and Health, The Swedish School of Sport and Health Sciences, GIH, Stockholm, Sweden.
    Wahlgren, Lina
    The Research Unit for Movement, Health and Environment, Department of Physical Activity and Health, The Swedish School of Sport and Health Sciences, GIH, Stockholm, Sweden.
    Schantz, Peter
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Section of Sustainable Health. The Research Unit for Movement, Health and Environment, Department of Physical Activity and Health, The Swedish School of Sport and Health Sciences, GIH, Stockholm, Sweden.
    Pedestrians' perceptions of route environments in relation to deterring or facilitating walking2022In: Frontiers In Public Health, ISSN 2296-2565, Vol. 10, article id 1012222Article in journal (Refereed)
    Abstract [en]

    Background: Every walk takes place in a route environment, and it can play an important role in deterring or facilitating walking, and will always affect the environmental unwell-well-being of pedestrians. The aim of this study is to illuminate which the important route environmental variables are in this respect. The focus is, therefore, on pedestrians' perceptions of route environmental variables and how they relate to overall appraisals of route environments as hindering–stimulating for walking and unsafe–safe for reasons of traffic.

    Methods: Commuting pedestrians in the inner urban area of Stockholm, Sweden (n = 294, 49.5 ± 10.4 years, 77% women), were recruited via advertisements. They evaluated their commuting route environments using a self-report tool, the Active Commuting Route Environment Scale (ACRES). Correlation, multiple regression, and mediation analyses were used to study the relationships between the variables and the outcome variables.

    Results: Aesthetics and greenery appear to strongly stimulate walking, whereas noise, a proxy for motorized traffic, hinders it. Furthermore, aesthetics is positively related to traffic safety, whereas conflicts have the opposite role. Conflicts is an intermediate outcome, representing several basic environmental variables, some of which were directly and negatively related to unsafe–safe traffic.

    Conclusion: Route environmental variables appear to be potent factors in deterring or facilitating walking. This knowledge is of importance for policymakers and urban planners when designing route environments with the aim of attracting new pedestrians, and simultaneously stimulating those who already walk to keep on.

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  • 5.
    Antonson, Hans
    et al.
    KMV Forum AB.
    Buckland, Philip I.
    Fröjmark Svanström, Karin
    KMV Forum AB.
    Eriksson, Camilla
    KMV Forum AB.
    Blomqvist, Göran
    Statens väg- och transportforskningsinstitut (VTI).
    Effekter av vintervägsaltning på kulturmiljö. En pilotstudie av fornlämningskategorin milstolpe2021Report (Other academic)
    Abstract [en]

    A semi-quantitative pilot study of 72 milestones (35 of limestone and 37 of cast iron) in the counties of Södermanland and Östergötland, respectively, has been carried out with the aim of studying the connection between winter road salting and damage to the milestones. Degradation of the mile-stones has been classified on the basis of high-resolution photographs, distance from the road and the compass orientation of the front side. The report shows that some parts of the milestones are more damaged than others, and that winter road salt is a probable explanation for this on the cast iron milestones. The relationship is not as clear for limestone milestones, and the study thus calls for further in-depth investigations. The simplified and relatively cost-effective semi-quantitative meth-odology developed in this pilot study has proven to work and has the potential to be refined. (Publication in Swedish).

  • 6.
    Aoshima, Koji
    et al.
    Umeå University, Faculty of Science and Technology, Department of Physics. Komatsu Ltd..
    Fälldin, Arvid
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Wadbro, Eddie
    Umeå University, Faculty of Science and Technology, Department of Computing Science. Karlstad University, Sweden.
    Servin, Martin
    Umeå University, Faculty of Science and Technology, Department of Physics. Algoryx Simulation.
    Data-driven models for predicting the outcome of autonomous wheel loader operationsManuscript (preprint) (Other academic)
    Abstract [en]

    This paper presents a method using data-driven models for selecting actions and predicting the total performance of autonomous wheel loader operations over many loading cycles in a changing environment. The performance includes loaded mass, loading time, work. The data-driven models input the control parameters of a loading action and the heightmap of the initial pile state to output the inference of either the performance or the resulting pile state. By iteratively utilizing the resulting pile state as the initial pile state for consecutive predictions, the prediction method enables long-horizon forecasting. Deep neural networks were trained on data from over 10,000 random loading actions in gravel piles of different shapes using 3D multibody dynamics simulation. The models predict the performance and the resulting pile state with, on average, 95% accuracy in 1.2 ms, and 97% in 4.5 ms, respectively. The performance prediction was found to be even faster in exchange for accuracy by reducing the model size with the lower dimensional representation of the pile state using its slope and curvature. The feasibility of long-horizon predictions was confirmed with 40 sequential loading actions at a large pile. With the aid of a physics-based model, the pile state predictions are kept sufficiently accurate for longer-horizon use.

  • 7. Asplund, Disa
    et al.
    Westin, Jonas
    Umeå University, Faculty of Social Sciences, Centre for Regional Science (CERUM).
    Modellering av slingor inom sjötransporter2017Report (Refereed)
    Abstract [en]

    The Swedish national freight transport model system Samgods is a freight model that simulates logistics decision at a disaggregated firm-to-firm level. The model calculates total annual transport demand in Sweden for all transport modes based on a deterministic cost minimization approach. The model cannot consolidate commodities of different commodity types in the same vessel, train or truck and can only simulate vessels using direct routes between two ports. This implies that many of the features of sea transport such as utilizing larger vessels and building loops to consolidate goods from different ports is not possible in the current Samgods version. In this paper, we analyze the effect of removing restrictions in sea transportation especially by allowing the ship operators to construct and utilize loops. In the new model, LIFREM (Loops Including FREight Model), the shippers’ choice of sea transport routes is modelled as a mixed integer linear programming optimization problem. In doing so, we make use of a case study on sea transport of forest products from Northern Sweden to Western Europe. The results show that allowing predefined loops decreases total logistic cost by 10% and allowing the shipper to freely select loops decreases the cost by 21%. These results show that modelling of loops is important in order to realistically represent the attractiveness of the sea transport mode. This is also confirmed by the fact that the sea mode share increases by 2–4% in LIFREM when loops are allowed.

  • 8.
    Axensten, Peder
    Umeå University, Faculty of Social Sciences, Centre for Regional Science (CERUM).
    Modelling the short-term impact of a nuclear accident on transportation flows2007In: Policy analysis of transport networks / [ed] Aura Reggiani; Marina van Geenhuizen; Piet Rietveld, Aldershot: Ashgate, 2007, 1, p. 61-75Chapter in book (Refereed)
    Abstract [en]

    This chapter discusses the accessibility impacts of the Trans-European Railway Network (TEN-T) for three different periods of time: the years 1995, 2005 and 2015. It presents a literature review of accessibility and discusses the intrinsic nature of distinct partial accessibility indicators. The chapter introduces Data Envelopment Analysis (DEA) proposal to synthesize the partial accessibility information in a sensible way, and presents the results of this new global approach. For instance, Paris is the city which provides better accessibility results with respect the location and potential market indicators in the three scenarios analysed, but it is below the fourth place regarding daily accessibility. The TEN-T is one of the basic policy instruments applied in the EU to achieve growth, competitiveness and employment. European transport policy has always called for an integrated approach combining inter alia measures to revitalize rail sector, and special emphasis has been dedicated to the development of High Speed Train (HST) corridors, in particular the cross-border corridors.

  • 9. Bandaragoda, Tharindu
    et al.
    De Silva, Daswin
    Kleyko, Denis
    Osipov, Evgeny
    Wiklund, Urban
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Radiation Physics.
    Alahakoon, Damminda
    Trajectory clustering of road traffic in urban environments using incremental machine learning in combination with hyperdimensional computing2019In: 2019 IEEE Intelligent Transportation Systems Conference (ITSC), IEEE, 2019, p. 1664-1670Conference paper (Refereed)
    Abstract [en]

    Road traffic congestion in urban environments poses an increasingly complex challenge of detection, profiling and prediction. Although public policy promotes transport alternatives and new infrastructure, traffic congestion is highly prevalent and continues to be the lead cause for numerous social, economic and environmental issues. Although a significant volume of research has been reported on road traffic prediction, profiling of traffic has received much less attention. In this paper we address two key problems in traffic profiling by proposing a novel unsupervised incremental learning approach for road traffic congestion detection and profiling, dynamically over time. This approach uses (a) hyperdimensional computing to enable capture variable-length trajectories of commuter trips represented as vehicular movement across intersections, and (b) transforms these into feature vectors that can be incrementally learned over time by the Incremental Knowledge Acquiring Self-Learning (IKASL) algorithm. The proposed approach was tested and evaluated on a dataset consisting of approximately 190 million vehicular movement records obtained from 1,400 Bluetooth identifiers placed at the intersections of the arterial road network in the State of Victoria, Australia.

  • 10.
    Behndig, Jonatan
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Optimization of Transport, Storage and Allocation of Production at Norra Timber2022Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Optimization is a method that is, as the name suggests, used to find the    optimal solution for different problems. In practice the method is used for    many different purposes, everything from minimizing the distance traveled by a traveling salesman, to maximizing the storage capacity of a warehouse. The purpose of this project was to develop a tool that, through the use of optimization finds a solution to production and transporting problem of the logistics at Norra Timber.

    To achieve this, a series of functions were written in MATLAB that read data files from the user. The functions then use that data to define and solve the production and transportation problem proposed by Norra Timber using a built in solver from the optimization toolbox in MATLAB. When the program has found a solution, it is exported into a series of Excel spreadsheets to make the results easier to read.

    The method was found to be successful in finding the optimal solution for all the different scenarios that were tested. In total, five different scenarios were tested. One baseline test and four scenarios where each one was built upon the scenario before it. At the end of the final scenario, the total cost of the production was reduced by approximately 1.15%, compared to the baseline test, which matched the expected cost reduction.

    In conclusion, the tool fulfills the requirements of functionality. It is efficient at testing different scenarios and finding the optimal solution. However, the tool does have minor inconveniences that can be improved upon. While they can be detrimental to the user experience, they do not affect the results.

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  • 11.
    Bjørnarå, Helga Birgit
    et al.
    Department of Sport Science and Physical Education, University of Agder, Kristiansand, Norway.
    Berntsen, Sveinung
    Department of Sport Science and Physical Education, University of Agder, Kristiansand, Norway.
    te Velde, Saskia J.
    Department of Sport Science and Physical Education, University of Agder, Kristiansand, Norway.
    Fyhri, Aslak
    Department of Safety and the Environment, Institute of Transport Economics, Oslo, Norway.
    Isaksen, Ketil
    Division for Model and Climate Analysis, Norwegian Meteorological Institute, Oslo, Norway.
    Deforche, Benedicte
    Department of Public Health and Primary Care, Faculty of Medicine and Health Sciences, Ghent University, Ghent, Belgium; Physical Activity, Nutrition and Health Research Unit, Faculty of Physical Education and Physical Therapy, Vrije Universiteit Brussel, Brussels, Belgium.
    Andersen, Lars Bo
    Faculty Education, Arts and Sports, Western Norway University of Applied Sciences, Sogndal, Norway.
    Stenling, Andreas
    Umeå University, Faculty of Social Sciences, Department of Psychology. Department of Sport Science and Physical Education, University of Agder, Kristiansand, Norway.
    Bere, Elling
    Department of Sport Science and Physical Education, University of Agder, Kristiansand, Norway; Department of Health and Inequalities, & Centre for Evaluation of Public Health Measures, Norwegian Institute of Public Health, Oslo, Norway.
    The impact of weather conditions on everyday cycling with different bike types in parents of young children participating in the CARTOBIKE randomized controlled trial2023In: International Journal of Sustainable Transportation, ISSN 1556-8318, E-ISSN 1556-8334, Vol. 17, no 2, p. 128-135Article in journal (Refereed)
    Abstract [en]

    Knowledge about how weather conditions affect travel behavior in different user groups and contexts is relevant for planners and policymakers to facilitate sustainable transportation systems. We aimed to assess the influence of day-to-day weather on cycling for transportation among parents of young children with access to different bike types (e-bike vs non e-bike) in a natural study setting over nine months. We hypothesized less impact of weather variability on cycling when using an e-bike compared with a non e-bike. A randomized, controlled trial was conducted in Southern Norway. The intervention group (n = 18) was in random order equipped with an e-bike with trailer for child transportation (n = 6), a cargo (longtail) bike (n = 6) and a traditional bike with trailer (n = 6), each for three months. These 18 participants reported cycling on 832 out of 3276 person-days (25%). We used dynamic structural equation modeling for intensive longitudinal data to examine the relations between daily weather conditions, bike type (e-bike vs traditional bike), and cycling (dichotomized daily at yes or no). Air temperature (positively) and wind speed (negatively) were both credible predictors of cycling, whereas the other predictors (precipitation in the morning (yes or no) and presence of snow (yes or no) were not. We added interaction terms between bike type and weather conditions, but none of the interaction terms had a credible effect on cycling. Thus, the relations between weather conditions and cycling were not moderated by bike type among parents of young children.

  • 12. Carlsson, Fredrik
    et al.
    Lampi, Elina
    Umeå University, Faculty of Social Sciences, Umeå School of Business and Economics (USBE), Economics.
    Martinsson, Peter
    The marginal values of noise disturbance from air traffic: does the time of the day matter?2004In: Transportation Research Part D: Transport and Environment, ISSN 1361-9209, E-ISSN 1879-2340, Vol. 9, no 5, p. 373-385Article in journal (Refereed)
    Abstract [en]

    This paper analyzes the marginal willingness to pay for changes in noise levels related to changes in the volume of flight movements at a city airport in Stockholm, Sweden, by using a choice experiment. When estimating marginal willingness to pay for different times of the day and days of the week, we find that these vary with the temporal dimensions: mornings and evenings have higher marginal values. Interestingly, a substantial proportion of the respondents prefer no changes in the current noise level. The paper concludes with a policy discussion related to incentive-based pricing.

  • 13.
    Edwards, Henrik
    et al.
    Sweco.
    Anderstig, Christer
    WSP.
    Westin, Jonas
    Umeå University, Faculty of Social Sciences, Centre for Regional Science (CERUM). Umeå University, Faculty of Science and Technology, Department of Mathematics and Mathematical Statistics.
    Börjesson, Jonas
    WSP.
    Lagnerö, Martin
    Sweco.
    Svensson, Kristofer
    Sweco.
    Samgods PWC-matriser 2019 och 2045: [Slutversion]2024Report (Other academic)
    Abstract [sv]

    Syftet med uppdraget är ta fram ny data avseende efterfrågan på godstransporter för Trafikverkets nationella godstransportmodell Samgods. Dessa data betecknas PWC-matriserdär PWC uttydes Production-Warehouse-Consumption, och de anger hur många ton per år av 16 olika varugrupper som transporteras mellan olika par av områden. Data ska avse det nya basåret 2019 (ingår i Trafikverkets uppsättning data betecknat BAS2024 från och med år 2024) och det nya prognosåret 2045 som kommer att tillämpas från och med 2024-04-01. Skapandet av PWC-matriserna utgör första steg i det modellkoncept som Samgodsmodellen bygger på1. I Samgods simuleras hur godsvolymerna transporteras på väg, med järnväg, till sjöss och i flygfrakt.

    Centrala indata för konstruktion av PWC-matriserna är varuflödesundersökningarna utförda 2021 respektive 2016, utrikeshandelsstatistik, socioekonomiska indata avseende sysselsättningens sammansättning i olika regioner och ekonomisk statistik.

    Befintlig metod har modifierats i ett antal väsentliga delar, se bilaga 11.1 för en sammanställning.

    Den metod som tidigare användes för att ta fram godsefterfrågematriser PWC 2040 har, vid tillämpningen för PWC 2045, genomgått vissa förändringar med avseende på grad av tillämpningsanpassning och datakällor. Dessa förändringar kan sammanfattas enlig tföljande:

    1. Tidigare utgick PWC för prognosår mer direkt från ett makroekonomiskt riksscenario från KI av typen ”beslutade åtgärder”. Denna gång anpassas PWC mer till de antaganden som Trafikverket gjort för vad som ska gälla för den Basprognos som ska tas fram vad gäller utsläppsmål för den inhemska transportsektorn. Detta innebär justeringar för betydligt lägre nivåer för olja och petroleum jämfört med riksscenariot enligt nedan.

    2. I riksscenariot antas en kraftigt ökad produktion av biobränslen vid substitution från fossila bränslen. För PWC 2045 antas istället att fossila bränslen i hög grad ersätts av elektricitet som energikälla.

    3. I PWC för 2045 antas en lägre nivå för utvecklingen av skogsråvara, som utgår från Skogsstyrelsens bedömningar, istället för de antaganden som är gjorda i KI:s riksscenario nämnt ovan. Även myndigheten SGU:s bedömning vad gäller jord, sten och grus har varit en utgångspunkt, som komplement till Ref22.

    4. En betydande metodförändring har gjorts avseende varuvärdesmodellen för att på en aggregerad nivå uppskatta hur volymer i ton utvecklas i förhållande till utvecklingen i monetära termer. På det viset erhålls en totalnivå för prognosåret i ton. Varuvärden för enskilda varugrupper prognosticeras fortfarande, men utan krav på att trenderna ska vara signifikanta. Sedan görs en sammanviktning av prognoser i monetära termer och varuvärden med hänsyn till att prognosårets summerade volymer i ton för de individuella varugrupperna ska överensstämma med den framtagna totalnivån för prognosåret.

    De framtagna PWC-matriserna har använts i en preliminär version av Samgodsmodellen version 1.2.2 sedan december 2022. Resultatet på en aggregerad nivå efter kalibrering uppvisar god överensstämmelse med transportarbete per trafikslag. Likaså bedöms resultat framtagna för 2045 på aggregerad nivå (NUTS2 och stora utrikes aggregat) som rimliga utifrån de förutsättningar som gäller.

  • 14. Eriksson, Lars
    et al.
    Palmqvist, Lisa
    Umeå University, Faculty of Social Sciences, Department of Psychology.
    Andersson Hultgren, Jonas
    Blissing, Björn
    Nordin, Steven
    Umeå University, Faculty of Social Sciences, Department of Psychology.
    Performance and presence with head-movement produced motion parallax in simulated driving2015In: Transportation Research Part F: Traffic Psychology and Behaviour, ISSN 1369-8478, E-ISSN 1873-5517, Vol. 34, p. 54-64Article in journal (Refereed)
    Abstract [en]

    Driving simulator studies can reveal relevant and valid aspects of driving behavior, but underestimation of distance and speed can negatively affect the driver's performance, such as in performance of overtaking. One possible explanation for the underestimation of distance and speed is that two-dimensional projection of the visual scene disrupts the monocular-based illusory depth because of conflicting binocular and monocular information of depth. A possible solution might involve the strengthening of the monocular information so that the binocular information becomes less potent. In the present study, we used an advanced high-fidelity driving simulator to investigate whether adding the visual depth information of motion parallax from head movement affects sense of presence, judgment of distance and speed, and performance measures coupled with overtaking. The simulations included two types of driving scenario in which one was urban and the other was rural. The main results show no effect of this head-movement produced motion parallax on sense of presence, head movement, time to collision, distance judgment, or speed judgment. However, the results show an effect on lateral positioning. When initiating the overtaking maneuver there is a lateral positioning farther away from the road center as effect of the motion parallax in both types of scenario, which can be interpreted as indicating use of naturally occurring information that change behavior at overtaking. Nevertheless, only showing tendencies of effects, absent is any clear additional impact of this motion parallax in the simulated driving.

  • 15.
    Forsén, Isak
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Materialspill i aktivt projekt: Hur ser situationen ut och kan mängden spill minskas?2021Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    SCA Obbola is a papermill that is investing in the future and is expanding its production. The project is called Expansion Obbola and they plan to increase their factory's capacity from 450,000 tonnes kraftliner to 725,000 tonnes. Peab is the contractor for the project, it started in 2018 and is expected to be completed by the year 2023. In collaboration with Peab, a report has been carried out on the Expansion Obbola project to find out how they work to minimize material waste. The report will also look into the current way of dealing with material waste and if the opportunity exists to reduce the amount of material waste even more. The purpose of the report is to get a clearer picture of the material waste on the project Expansion Obbola, to further enable and expand Peab's work with material waste in an efficient, economical and environmentally friendly way. The report also aims to contribute to Peab's future work with material waste in a positive way. During the production of a new building, it is estimated that 30-40% of total cost consists of material costs, which means that if the amount of material waste can be limited, it can contribute to a more sustainable, economical and environmentally friendly way of building. This report resulted in that the situation in project Expansion Obbola is consisting of some difficulties and that it significantly complicates the possibility of reducing the material waste. Pressured time schedule, lack of space and limited guidelines on how to handle material waste are the main difficulties that the project poses but after the completion of this report, it is still considered that there are plenty of development areas for the project regarding material waste. Some of the presented proposals on how to work to reduce the amount of material waste are: Changing the day and time for revision of drawings, increase the cooperation between supervisors, change the wood for casting to a lower quality to spare the environment and expand the collaboration with the designers. The Expansion Obbola project is therefore considered, despite difficult conditions, to have good opportunities to improve its work with material waste and potentially be able to reduce the amount of material that is thrown away unnecessarily.

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  • 16.
    Garvill, Jörgen
    et al.
    Umeå University, Faculty of Social Sciences, Department of Psychology.
    Gärling, Fredrik
    Umeå University, Faculty of Social Sciences, Department of Geography and Economic History, Economic and social geography, Transportation Research Unit (TRUM).
    Marell, Agneta
    Umeå University, Faculty of Social Sciences, Umeå School of Business and Economics (USBE).
    Westin, Kerstin
    Umeå University, Faculty of Social Sciences, Department of Social and Economic Geography.
    Smart fart: Rekrytering av testförare och montering av fartkollare2001Report (Other (popular science, discussion, etc.))
  • 17.
    Granlund Nilsson, Mattias
    Umeå University, Faculty of Science and Technology, Umeå Institute of Design.
    Artisan: Professional urban mobility2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The idea for this project initially came from an article i read about a small company in Stockholm, called “The cycling plumber” In the article, the founder of the company who explained that he was tired of looking for parking and sitting in traffic in his work-van around the tight and congest- ed streets of Stockholm. This sparked an interest from me, what options does the urban-operating handyman have in terms of transportation?

    Using the design process and thorough user studies, this project explores a new type of commercial vehicle segement, intended for carpenters operating in the dense city traffic of the future. The final product proposed, is called VW Artisan. It’s a versatile commercial vehicle utilizing a detachable toolbox system to improve the efficiency and comfort of the user during their daily work.

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  • 18. Hajdu, László
    et al.
    Bóta, András
    Umeå University, Faculty of Science and Technology, Department of Physics. Research Centre for Integrated Transport Innovation, School of Civil and Environmental Engineering, University of New South Wales, Sydney, Australia.
    Krész, Miklós
    Khani, Alireza
    Gardner, Lauren M.
    Discovering the Hidden Community Structure of Public Transportation Networks2020In: Networks and Spatial Economics, ISSN 1566-113X, E-ISSN 1572-9427, Vol. 20, no 1, p. 209-231Article in journal (Refereed)
    Abstract [en]

    Advances in public transit modeling and smart card technologies can reveal detailed contact patterns of passengers. A natural way to represent such contact patterns is in the form of networks. In this paper we utilize known contact patterns from a public transit assignment model in a major metropolitan city, and propose the development of two novel network structures, each of which elucidate certain aspects of passenger travel behavior. We first propose the development of a transfer network, which can reveal passenger groups that travel together on a given day. Second, we propose the development of a community network, which is derived from the transfer network, and captures the similarity of travel patterns among passengers. We then explore the application of each of these network structures to identify the most frequently used travel paths, i.e., routes and transfers, in the public transit system, and model epidemic spreading risk among passengers of a public transit network, respectively. In the latter our conclusions reinforce previous observations, that routes crossing or connecting to the city center in the morning and afternoon peak hours are the most "dangerous" during an outbreak.

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  • 19.
    Harisubramanyabalaji, Subramani Palanisamy
    et al.
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics. Scania CV AB, Södertälje, Sweden.
    ur Réhman, Shafiq
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Nyberg, Mattias
    Gustavsson, Joakim
    Improving Image Classification Robustness Using Predictive Data Augmentation2018In: Computer Safety, Reliability, and Security: SAFECOMP 2018 / [ed] Gallina B., Skavhaug A., Schoitsch E., Bitsch F., Springer, 2018, p. 548-561Conference paper (Refereed)
    Abstract [en]

    Safer autonomous navigation might be challenging if there is a failure in sensing system. Robust classifier algorithm irrespective of camera position, view angles, and environmental condition of an autonomous vehicle including different size & type (Car, Bus, Truck, etc.) can safely regulate the vehicle control. As training data play a crucial role in robust classification of traffic signs, an effective augmentation technique enriching the model capacity to withstand variations in urban environment is required. In this paper, a framework to identify model weakness and targeted augmentation methodology is presented. Based on off-line behavior identification, exact limitation of a Convolutional Neural Network (CNN) model is estimated to augment only those challenge levels necessary for improved classifier robustness. Predictive Augmentation (PA) and Predictive Multiple Augmentation (PMA) methods are proposed to adapt the model based on acquired challenges with a high numerical value of confidence. We validated our framework on two different training datasets and with 5 generated test groups containing varying levels of challenge (simple to extreme). The results show impressive improvement by 5-20% in overall classification accuracy thereby keeping their high confidence.

  • 20.
    Hosseini, S. Ahmad
    et al.
    Umeå University, Faculty of Science and Technology, Department of Computing Science.
    Sahlin, Tobias
    Umeå University, Faculty of Science and Technology, Department of Mathematics and Mathematical Statistics.
    An optimization model for management of empty containers in distribution network of a logistics company under uncertainty2019In: Journal of Industrial Engineering International, ISSN 1735-5702, E-ISSN 2251-712X, Vol. 15, no 4, p. 585-602Article in journal (Refereed)
    Abstract [en]

    In transportation via containers, unbalanced movement of loaded containers forces shipping companies to reposition empty containers. This study addresses the problem of empty container repositioning (ECR) in the distribution network of a European logistics company, where some restrictions impose decision making in an uncertain environment. The problem involves dispatching empty containers of multiple types and various conditions (dirty and clean) to meet the on-time delivery requirements and repositioning the other containers to terminals, depots, and cleaning stations. A multi-period optimization model is developed to help make tactical decisions under uncertainty and data shortage for flow management of empty containers over a predetermined planning horizon. Employing the operational law of uncertainty programming, a new auxiliary chance-constrained programming is established for the ECR problem, and we prove the existence of an equivalence relation between the ECR plans in the uncertain network and those in an auxiliary deterministic network. Exploiting this new problem, we give the uncertainty distribution of the overall optimal ECR operational cost. The computational experiments show that the model generates good-quality repositioning plans and demonstrate that cost and modality improvement can be achieved in the network.

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  • 21.
    Häggström Lundevaller, Erling
    Umeå University, Faculty of Social Sciences, Department of Statistics. Umeå University, Faculty of Social Sciences, Centre for Population Studies (CPS).
    The effect of travel cost on frequencies of shopping and recreational trips in Sweden2009In: Journal of Transport Geography, ISSN 0966-6923, E-ISSN 1873-1236, Vol. 17, no 3, p. 208-215Article in journal (Refereed)
    Abstract [en]

    This article focus on how the cost of travel affects travel behavior. A trip frequency model for recreational and shopping trips is suggested and used to investigate this. The data that is used comes from a Swedish travel habit survey where the respondents’ trip frequencies of both types of trips on a certain day are recorded. This is likely to introduce a correlation structure, which is incorporated in the model. Special attention is paid to the effect of travel cost on trip frequencies for different regions and income groups. As a measure of the sensitivity of cost changes, elasticity of demand is calculated. The precision of the elasticities are evaluated with simulated p-values.

  • 22.
    Jensen, Maarten
    et al.
    Utrecht University, Utrecht, Netherlands.
    Dignum, Frank
    Umeå University, Faculty of Science and Technology, Department of Computing Science. Utrecht University, Utrecht, Netherlands; CVUT Prague, Prague, Czech Republic.
    Drug Trafficking As Illegal Supply Chain - A Social Simulation2021In: Advances in Social Simulation: Proceedings of the 15th Social Simulation Conference: 23–27 September 2019 / [ed] Petra Ahrweiler, Martin Neumann, Springer, 2021, p. 9-22Conference paper (Refereed)
    Abstract [en]

    Cocaine trafficking is starting to get modeled by supply chain theory. Supply chain theories are described in many economical papers. These theories are however not directly usable in analyzing illegal supply chains. In this paper we investigate the difference between legal and illegal supply chains. Where the difference of the supply chain lies in two factors, these are trust and risk. Here we model a cocaine trafficking supply chain based on legal supply chain theory. This model will be copied and adjusted with theoretical concepts that are inherent to an illegal supply chain. Comparison of the results of the two models showed that differences in those factors lead to differences in the supply chain, such as clustering and efficiency.

  • 23.
    Johansson, Magnus
    et al.
    VTI, Statens väg- och transportforskningsinstitut.
    Karlsson, Rune
    VTI, Statens väg- och transportforskningsinstitut.
    Westin, Jonas
    Umeå University, Faculty of Social Sciences, Centre for Regional Science (CERUM).
    Sjöfart mot svensk hamn 2007 till 2019: förändringar i volym, struktur och rörelsemönster2020Report (Refereed)
    Abstract [en]

    Using ship positional data to study maritime traffic calling at Swedish ports from has long been an underutilized potential. In this project, the possibilities of using information from the automatic identification system (AIS) are investigated, including how this information can be used to complement the official statistics covering maritime traffic calling at Swedish ports. 

    Using AIS, it is possible to track and compile the movements of individual vessels in the Baltic Sea, Kattegatt and the eastern parts of Skagerack through the geographic positioning signals sent by ships approximately every ten seconds. In order to use this information, some sort of method is needed to handle the generated amounts of data. In this project, a method has been developed which can be briefly described as consisting of two steps. In the first step, the amount of AIS data is limited by filtering out the datapoints wherein ships pass in and out of ports. For every passage in and out of a port there is a corresponding date and time. In the second step, the port calls are sequenced chronologically so that a vessel’s pattern of movement through the Baltic Sea area can be tracked. Finally, these datapoints can be matched against the information regarding dates, which is available in the official statistics. This matching process allows the resulting database of voyages and port calls to be complemented with loaded and unloaded cargo volumes in Swedish ports. Using the created database, the development of maritime traffic calling at Swedish ports can be studied during the period 2007 to 2018.

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  • 24.
    Jonsson, Daniel R.
    et al.
    Kungliga Tekniska Högskolan, Stockholm, Sverige.
    Adolphsson, Marcus
    Kungliga Tekniska Högskolan, Stockholm, Sverige.
    Westin, Jonas
    Umeå University, Faculty of Social Sciences, Centre for Regional Science (CERUM).
    Regionala systemanalyser: slutrapport2017Report (Other academic)
    Abstract [sv]

    Bakgrund: År 2008 införde Trafikverket ett nytt planeringsinstrument i form av regionala systemanalyser. Syftet var att förbättra fokus och måluppfyllelse i transportplaneringen. För att möta efterfrågan på dagens och framtidens transportbehov på regional och nationell nivå och för att möta de transportpolitiska målen behöver trafikslagen komplettera varandra. Resultatet från de regionala systemanalyserna bör också vara möjliga att aggregera från regional till nationell nivå.

    Utifrån ändrade förutsättningar, förändrad planering och svårighet att överföra resultaten i 2008 års regionala systemanalyser till en nationell analys, och dessutom att tillhandahållainformation inför senare planeringssteg om åtgärdsvalstudier, tog Trafikverket initiativ till denna forskning (Trafikverket, 2013). 

  • 25.
    Liu, Minzhang
    et al.
    School of Energy and Safety Engineering, Tianjin Chengjian University, Tianjin, China.
    Li, Chanyuan
    School of Energy and Safety Engineering, Tianjin Chengjian University, Tianjin, China.
    Chang, Ru
    School of Energy and Safety Engineering, Tianjin Chengjian University, Tianjin, China.
    Yang, Bin
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics. School of Energy and Safety Engineering, Tianjin Chengjian University, Tianjin, China.
    Lai, Yanping
    School of Energy and Safety Engineering, Tianjin Chengjian University, Tianjin, China.
    Liu, Weiyue
    School of Energy and Safety Engineering, Tianjin Chengjian University, Tianjin, China.
    Zhang, Huan
    School of Environmental Science and Engineering, Tianjin University, Tianjin, China; National Engineering Laboratory for Digital Construction and Evaluation Technology of Urban Rail Transit, Tianjin, China.
    Numerical study on aerodynamic pressure caused by high-speed train passing through the subway station2024In: The International Journal of Ventilation, ISSN 1473-3315, E-ISSN 2044-4044Article in journal (Refereed)
    Abstract [en]

    As the demand for efficient travel increased, the train speed is greatly increased and the subway gradually appeared the express train and the slow train. Express trains pass through some stations without stopping. In this case, the pressure transient phenomenon in the tunnel will become severe. In this study, the dynamic mesh simulation is used to study the pressure variations of the tunnel, platform screen door (PSD), and airshaft caused by the piston wind which is generated by the high-speed train passing through the tunnel and station. The effects of train speed, modes of the train passing through the station, number of airshafts and station types on the aerodynamic pressure are analyzed. The results demonstrate that the increase in train speed brings new challenges to the loading capacity of tunnel structure. Airshafts are set at the entrance and exit of the station, which is conducive to the pressure relief of each part of the tunnel structure. Furthermore, a new type of station with two tracks (express line and slow line) is conducted. The peak pressure of PSD is reduced by 48% compared with the conventional station. This study will contribute to the improvement of subway construction and provide theoretical and data support for the operation of the high-speed train.

  • 26.
    Nilsson Sommar, Johan
    et al.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Section of Sustainable Health.
    Johansson, Christer
    Lövenheim, Boel
    Markstedt, Anders
    Strömgren, Magnus
    Umeå University, Faculty of Social Sciences, Department of Geography.
    Forsberg, Bertil
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Section of Sustainable Health.
    Potential Effects on Travelers' Air Pollution Exposure and Associated Mortality Estimated for a Mode Shift from Car to Bicycle Commuting2020In: International Journal of Environmental Research and Public Health, ISSN 1661-7827, E-ISSN 1660-4601, Vol. 17, no 20, article id 7635Article in journal (Refereed)
    Abstract [en]

    This study aims to use dispersion-modeled concentrations of nitrogen oxides (NOx) and black carbon (BC) to estimate bicyclist exposures along a network of roads and bicycle paths. Such modeling was also performed in a scenario with increased bicycling. Accumulated concentrations between home and work were thereafter calculated for both bicyclists and drivers of cars. A transport model was used to estimate traffic volumes and current commuting preferences in Stockholm County. The study used individuals' home and work addresses, their age, sex, and an empirical model estimate of their expected physical capacity in order to establish realistic bicycle travel distances. If car commuters with estimated physical capacity to bicycle to their workplace within 30 min changed their mode of transport to bicycle, >110,000 additional bicyclists would be achieved. Time-weighted mean concentrations along paths were, among current bicyclists, reduced from 25.8 to 24.2 mu g/m(3) for NOx and 1.14 to 1.08 mu g/m(3) for BC. Among the additional bicyclists, the yearly mean NOx dose from commuting increased from 0.08 to 1.03 mu g/m(3). This would be expected to yearly cause 0.10 fewer deaths for current bicycling levels and 1.7 more deaths for additional bicycling. This increased air pollution impact is much smaller than the decrease in the total population.

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  • 27.
    Nilsson Sommar, Johan
    et al.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Section of Sustainable Health.
    Johansson, Christer
    Department of Environmental Science, Stockholm University, Stockholm, Sweden; Environment and Health Administration, SLB, Stockholm, Sweden..
    Lövenheim, Boel
    Environment and Health Administration, SLB, Stockholm, Sweden..
    Schantz, Peter
    The Research Unit for Movement, Health and Environment, The Swedish School of Sport and Health Sciences, GIH, Stockholm, Sweden..
    Markstedt, Anders
    WSP Civils, Stockholm, Sweden..
    Strömgren, Magnus
    Umeå University, Faculty of Social Sciences, Department of Geography.
    Stigson, Helena
    Folksam Research, Stockholm, Sweden. Division of Insurance Medicine, Karolinska Institutet, Stockholm, Sweden..
    Forsberg, Bertil
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Section of Sustainable Health.
    Overall health impacts of a potential increase in cycle commuting in Stockholm, Sweden2022In: Scandinavian Journal of Public Health, ISSN 1403-4948, E-ISSN 1651-1905, Vol. 50, no 5, p. 552-564Article in journal (Refereed)
    Abstract [en]

    AIMS: To estimate the overall health impact of transferring commuting trips from car to bicycle.

    METHODS: In this study registry information on the location of home and work for residents in Stockholm County was used to obtain the shortest travel route on a network of bicycle paths and roads. Current modes of travel to work were based on travel survey data. The relation between duration of cycling and distance cycled was established as a basis for selecting the number of individuals that normally would drive a car to work, but have a distance to work that they could bicycle within 30 minutes. The change in traffic flows was estimated by a transport model (LuTrans) and effects on road traffic injuries and fatalities were estimated by using national hospital injury data. Effects on air pollution concentrations were modelled using dispersion models.

    RESULTS: Within the scenario, 111,000 commuters would shift from car to bicycle. On average the increased physical activity reduced the one-year mortality risk by 12% among the additional bicyclists. Including the number of years lost due to morbidity, the total number of disability adjusted life-years gained was 696. The amount of disability adjusted life-years gained in the general population due to reduced air pollution exposure was 471. The number of disability adjusted life-years lost by traffic injuries was 176. Also including air pollution effects among bicyclists, the net benefit was 939 disability adjusted life-years per year.

    CONCLUSIONS: Large health benefits were estimated by transferring commuting by car to bicycle.

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  • 28.
    Némethy, Oscar
    Umeå University, Faculty of Science and Technology, Umeå Institute of Design.
    Exploring Community Group Buying to Find Last Mile Solutions with Integrated Reverse Flows In 20302022Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
  • 29.
    Olsson, Oscar
    Umeå University, Faculty of Science and Technology, Umeå Institute of Design.
    SC Vega: Den fjärrstyrda räddningsfarkosten2021Independent thesis Basic level (degree of Bachelor of Fine Arts), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Swedish Sea Rescue Society (SSRS) is a voluntary organization that is responsible for the majority of all sea rescue missions in Sweden. In the past year, the organization has received an increased number of mission as a result of, among other things, more Swedes choosing to celebrate summers at home in Sweden.My thesis revolves around how to use modern technology in order to design a remotely controlled rescue vessel that can facilitate the Swedish Sea Rescue Society during less urgent missions, so-called membership missions, or preventive rescue missions as they are also called. These missions make up the majority of the organizations missions. The project has been carried out in collaboration with the Swedish Sea Rescue Society and has followed a classic design methodology based on research and interviews with people who touch on the chosen problem area, in order to give the project a relevant and solid foundation.

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    Oscar Olsson SC Vega Rapport 2021
  • 30.
    Persson, Anna
    et al.
    Department of Biomedical Engineering, Linköping University, Linköping, Sweden; Väderstad Ab, Väderstad, Sweden.
    Jonasson, Hanna
    Department of Biomedical Engineering, Linköping University, Linköping, Sweden.
    Fredriksson, Ingemar
    Department of Biomedical Engineering, Linköping University, Linköping, Sweden.
    Wiklund, Urban
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Radiation Physics.
    Ahlstrom, Christer
    Swedish National Road and Transport Research Institute, Linköping, Sweden.
    Heart Rate Variability for Classification of Alert Versus Sleep Deprived Drivers in Real Road Driving Conditions2021In: IEEE transactions on intelligent transportation systems (Print), ISSN 1524-9050, E-ISSN 1558-0016, Vol. 22, no 6, p. 3316-3325, article id 9055218Article in journal (Refereed)
    Abstract [en]

    Driver sleepiness is a contributing factor in many road fatalities. A long-standing goal in driver state research has therefore been to develop a robust sleepiness detection system. It has been suggested that various heart rate variability (HRV) metrics can be used for driver sleepiness classification. However, since heart rate is modulated not only by sleepiness but also by several other time-varying intra-individual factors such as posture, distress, boredom and relaxation, it is relevant to highlight not only the possibilities but also the difficulties involved in HRV-based driver sleepiness classification. This paper investigates the reliability of HRV as a standalone feature for driver sleepiness detection in a realistic setting. Data from three real-road driving studies were used, including 86 drivers in both alert and sleep-deprived conditions. Subjective ratings based on the Karolinska sleepiness scale (KSS) were used as ground truth when training four binary classifiers (k-nearest neighbours, support vector machine, AdaBoost, and random forest). The best performance was achieved with the random forest classifier with an accuracy of 85%. However, the accuracy dropped to 64% for three-class classification and to 44% for subject-independent, leave-one-participant-out classification. The worst results were obtained in the severely sleepy class. The results show that in realistic driving conditions, subject-independent sleepiness classification based on HRV is poor. The conclusion is that more work is needed to control for the many confounding factors that also influence HRV before it can be used as input to a driver sleepiness detection system.

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  • 31.
    Persson, Sabina
    Umeå University, Faculty of Science and Technology, Department of Mathematics and Mathematical Statistics.
    Optimering av lastplatser i leveransnätverk: Ett examensarbete utfört på uppdrag av Pågen AB2016Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [sv]

    Pågen har i dagsläget 61 lastplatser runtom i Sverige där deras egen säljkår lastar brödpallarna på sina lastbilar. Respektive säljare kör sedan en förutbestämd rutt där de själva distribuerar försäljningen på respektive butik.

    Syftet med rapporten är att analysera Pågens lastplatser för att undersöka var det finns möjlighet till nedläggningar som kan leda till kostnadsbesparingar. Dessa kostnadsbesparingar får dock inte resultera i minskad försäljningstid ute hos kund eller orimligt höga dieselkostnader.

    Projektet avgränsades till de lastplatser som låg närmre än fyra mil ifrån varandra samt två olika tripplar. Det har inneburit en omfattande nulägesanalys samt datainsamling för att få en helhetsbild av hur nätverket ser ut i dagsläget. Därefter skapades först en Matlabmodell för tyngdpunktsmetoden för lastplatserna Ljungby och Värnamo, sedan en Pythonmodell som kopplades till Google Maps API för att kunna utvärdera avståndsförändringen vid nedläggning av en lastplats samt dieselkostnaderna.

    Resultatet från Pythonmodellen sammanställdes manuellt i olika tabeller för att sedan ligga till grund för alla möjliga scenarion. Dessa scenarion ställdes upp i olika vektorer med en uträkning av vinsten för respektive, där tanken var att de skulle ligga till grund för ett matchningsproblem. På grund av resultatet som genererades behövdes det steget dock inte genomföras.

    Den slutgiltiga rekommendationen till Pågen är att de ska fortsätta en nedläggning av lastplatsen i Falkenberg. Vid en nedläggning av denna med flytt av rutterna till Varberg skulle vinsten bli 13 624,8 SEK/månad vid jämförelse av ökade dieselkostnader samt intjänad hyra vid nedläggning.

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    Optimering av lastplatser i leveransnätverk
  • 32.
    Sarkki, Simo
    et al.
    Umeå University, Faculty of Arts, Várdduo – Centre for Sámi Research. Cultural Anthropology, University of Oulu, Oulu, Finland.
    Rasmus, Sirpa
    Landauer, Mia
    Lépy, Élise
    Heikkinen, Hannu, I.
    Matching societal knowledge demand, research funding and scientific knowledge supply: trends and co-creation dynamics around reindeer management in Finland2021In: Polar Geography, ISSN 1088-937X, E-ISSN 1939-0513, Vol. 44, no 2, p. 90-111Article in journal (Refereed)
    Abstract [en]

    Matching knowledge Demand, research Funding and knowledge Supply (DFS) is important in order to enhance societally and policy relevant research, target funding appropriately and enhance the connectivity between science, policy and society. The DFS field around reindeer management in Finland offers a fertile case study to examine interconnected and complex trends as well as the relations between herders' and policymakers' knowledge demand, ministerial funding and independent supply of knowledge by science. We identify matches and mismatches between the DFS in a case study of reindeer management in Finland across ten inductively identified themes and in time scales of 2000-2009 and 2010-2018. The main finding was that, during the latter period, the DFS matched significantly better than in the earlier period. In order to explain this, we identify and discuss five alternative and legitimate co-creation dynamics that explain how the DFS is organizing around the reindeer management in Finland. The five dynamics represent variations in the co-creation approach, fit to varying situations, which can inform of alternative ways to better match the DFS around reindeer management, and they are also applicable in other contexts.

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  • 33.
    Sundin, Emma
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Women's perceived security in shared autonomous vehicles: The impact of identifying co-passengers2022Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The present thesis aims to establish ideas and technical solutions that can have a positive impact on women's perceived safety while traveling in autonomous vehicles, made for sharing with strangers. The method follows the Design Thinking model which contributes to a user-centered design approach. Initial literature research was performed to understand the problem area, which included women's issues in public transportation, the development of autonomous vehicles, the foundation of a trusting behavior and authentication technologies for identifying users. Following ideation workshops with eight potential users of the service contributed with ideas based on the female perspective and their expectations of traveling in a shared mobility alternative. These results provide a foundation that contributes to a specific purpose of the thesis to create and evaluate strategies for authentication of co-passengers due to being advocated by the participants. Two versions of a high-fidelity mobile application prototype were created in Figma with different strategies for how to interact with the service and authentication methods to align with the autonomous vehicle prototype provided by NEVS during the following tests. 

    The final user tests, with 14 participants, indicate that an identification method should be included in the service, especially during the night. Six of seven female participants appreciate a combination of Bank ID while requesting a ride and facial recognition when boarding the vehicle. However, the results of the male participants vary to a larger extent. The results do not indicate where the identification technology should be implemented, in the private phone or the vehicle doors. To create a solution available to a larger target group, the mobile application need to adopt and provide option alternatives regarding identification methods due to individual differences and previous experiences which lays a foundation for the users' ability to contribute to a trusting behavior. Furthermore, an onboarding process for the first-time user is proposed to prepare the user and describe how the service could be used and what is expected by them.

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  • 34.
    Säterdahl, Ida
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    De vanligaste tillbuden vid vägarbeten och hur de kan förebyggas2022Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Vägnätet spelar en viktig roll för ett fungerande samhälle, men samtidigt innebär trafiken en stor risk. Globalt var trafikolyckor den vanligaste orsaken till barn och ungas död i åldern 5 – 29 år under år 2016. Samma år dog 1,35 miljoner människor i trafiken världen över. Att halvera antalet dödsfall i trafiken till år 2020 är ett av delmålen i agenda 2030 samtidigt som andra mål handlar om en trygg och säker arbetsmiljö, koppla ihop samhällen och göra transportsystem tillgängliga för alla. Det ställer krav på utbyggnad och underhåll av transportsystemet samtidigt som säkerheten måste höjas.

    Trots att Sverige är ett av länderna med högst trafiksäkerhet i världen sker varje år flera trafikolyckor med dödlig utgång. År 2020 dog 204 personer i trafiken. Riksdagen tog år 1997 ett beslut om nollvisionen där målet var att ingen skulle dö eller skadas allvarligt i Sveriges transportsystem på sikt. Mellan åren 2003 - 2015 uppskattas att minst 3958 olyckor skett i anslutning till vägarbeten i Sverige. Bygg- och anläggningsbranschen var år 2020 den bransch där flest omkom. Svevia går i samma riktning som nollvisionen med sin vision om noll olyckor och branschens säkraste arbetsplats och säkraste trafikmiljö. För att nå målet krävs ett ständigt arbete för att förebygga risker och olyckor.

    Genom att studera Svevias inrapporterade tillbud kan risker upptäckas i tid vilket ger en möjlighet att hinna förebygga dessa innan en olycka sker. Syftet med detta examensarbete är att kunna bidra till en förbättrad arbetsmiljö inom drift av väg samt en ökad trafiksäkerhet förbi vägarbeten. Målet är att föreslå möjliga åtgärder som kan minska risken för de vanligaste tillbuden.

    De studerade tillbuden visar att i 44% av fallen var oaktsamma trafikanter eller brist på respekt för vägarbetet orsaken till tillbudet. För 12% var orsaken hög fart, för 11% var orsaken mänskliga faktorn och för 10% fel på fordon/utrustning. I resterande 23% kategoriserades orsaken som övrigt. Detta beror på en stor spridning av svaren och att en orsak endast förekom ett fåtal gånger. Exempel ur kategorin övrigt är renar på vägen.

    Med hjälp av de studerade tillbuden har åtgärder tagits fram som kan bidra till en möjlig minskning av tillbuden samt förebygga olyckor. En viktig åtgärd är att minska machokulturen inom bygg- och anläggningsbranschen som kan bidra negativt till säkerheten på arbetsplatser. Att höja allmänhetens respekt för vägarbeten är också viktigt.

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  • 35.
    Teimouri, Fateme
    et al.
    Umeå University, Faculty of Science and Technology, Department of Computing Science.
    Richter, Kai-Florian
    Umeå University, Faculty of Science and Technology, Department of Computing Science.
    Abstracting routes to their route-defining locations2022In: Computers, Environment and Urban Systems, ISSN 0198-9715, E-ISSN 1873-7587, Vol. 91, article id 101732Article in journal (Refereed)
    Abstract [en]

    Today's navigation assistance systems provide turn-by-turn instructions, which only focus on the next decision to take without offering any larger context. Information presentation is uniform and disconnected, i.e., any local instruction is equally important and not linked to any other decisions or the overall route context. This differs from how people usually give instructions and hinders spatial learning. In order to (re-)establish this larger context, we present an approach to identifying those locations along a route that define its characteristics, termed route-defining locations. These are prominent, easily recognized locations, which help relating the route to an environment's overall structure and a navigator's existing knowledge about the environment. The approach allows for determining route-defining locations on different levels of detail. Thus, at the same time it offers a mechanism for simplifying (or abstracting) a route. In this paper, we particularly focus on the latter aspect, presenting in detail the approach for identifying route-defining locations. For a given route, we, first, simplify its shape to extract those turns along the route that characterize its overall shape. Then, we rank landmarks and streets along the route based on their prominence. Finally, we include in the simplified route those turns that correspond to the locations of the most prominent landmarks and streets. The result is a set of route-defining locations extracted from the route shape, and prominent landmarks and streets along the route. In an agent-based simulation, we then evaluate the approach's ability to abstract a route to its characteristics, i.e., the defining locations. Results show that, indeed, our approach is effective in that respect, but success depends on ‘matching’ abstraction to an agent's knowledge about the environment.

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  • 36.
    Vierth, Inge
    et al.
    VTI, Statens väg- och transportforskningsinstitut.
    Karlsson, Rune
    VTI, Statens väg- och transportforskningsinstitut.
    Westin, Jonas
    Umeå University, Faculty of Social Sciences, Centre for Regional Science (CERUM).
    Validering av sjötransporter i Samgodsmodellen Version 1.12016Report (Refereed)
    Abstract [en]

    The project analyzes how well sea transports are modelled in the Swedish national freight model system Samgods. This first report comprises a short description of Version 1.1 of the model including calibration, a comparison of model results and statistics in 2012 as well as sensitivity analyses to test how the model reacts to different types of interventions. The second report, VTI notat 31-2016 Modeling of loops in maritime transport – Case Study of SCA's RoRo operations in the Baltic Sea, examines how big the problem is that Samgods does not model loops (vessels calling more than two ports during a trip). The existing Samgods model is a deterministic cost-minimizing model. It consists of several partially interacting modules: a) base matrices that describe the demand for 32 commodities, b) the logistics model that contains submodules for the choice of consignment size, consolidation of shipments from different senders, choice of transport chains, treatment of empty transports etc. and c) the rail capacity management tools (RCM) addressing capacity constraints in the Swedish rail network. The calibration of the model focuses on tonne-km and modal split in Sweden as well as different regional distributions of the tonnes transported, but the distribution over vessels types is not taken into account. Our analyses show that the model calculates about four times as many tonnes transported by container vessels than the statistics. We see a need to check if the input data used for the modelling of container transports (vs conventional transports) is realistic. Throughput (loaded/unloaded tonnes goods) was calibrated for 14 coastal sections and twelve aggregated commodities. However, we believe that the throughput per port should be a calibration target. The distribution of the gods on the ports is crucial in analyses of investments in fairways, locks etc. Furthermore, the distribution of the port calls vessel categories and -size classes was not a calibration target. We show that Samgods model overestimates the number of calls to all freight vessels with about 50 percent. The number of container vessel calls is about five times higher as in the Swedish Maritime Administration’s database. The number of roro-vessel calls is about two times as high. The conformity for the other vessels is very good. One explanation for the fact that number of container vessel calls is overestimated is of course that the amount of tonnes transported in containers is overestimated considerably. We show that almost all container vessels are expected to be in the model’s smallest of four size classes (up to 5 300 dead weight tonnes). The results indicate that Samgods is not able to model the use of larger container vessels due to the exploitation of economies of scale (which is very common in reality). The result for ro-ro vessels goes in the same direction but is not that extreme. For other vessels, the results are more consistent with the statistics. We think it is important to distinguish between different vessel types and with different production systems in the modelling. The load factors for loaded vehicles (and empty transports) were not part of the calibration. Today it is not possible to validate loading factors in various vehicles and vessels against statistics. The model calculates higher load factors for road (75–94 percent) and rail (86–97 percent) than for sea transports (0–73percent). Given the existing model only allows for consolidation within the 32 commodities, we tested the aggregation to twelve commodities. The results show that this contributes to a higher share for sea transports and the use of larger vessels size classes. This indicates that a higher degree of 10 VTI notat 30-2016 consolidation is achieved with fewer commodities. The same applies to a hypothetical doubling or tenfold increase in freight transport demand. In the latter two analyses, it becomes obvious that the potential of the rail mode to consolidate more is limited because both trains and rail infrastructure are well utilized in the base. Regarding consolidation, there are parallels between rail and sea and we think it would be interesting to study the similarities and differences in modeling.

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  • 37.
    von Hofsten, Hugo
    Umeå University, Faculty of Science and Technology, Umeå Institute of Design.
    Ergonomi för skidpatrull2021Independent thesis Basic level (degree of Bachelor of Fine Arts), 10 credits / 15 HE creditsStudent thesis
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    Ergonomi för skidpatrull - Rapport
  • 38.
    Wang, Jianfeng
    et al.
    Umeå University, Faculty of Science and Technology, Department of Mathematics and Mathematical Statistics.
    Granlöf, Markus
    Umeå University, Faculty of Science and Technology, Department of Mathematics and Mathematical Statistics.
    Yu, Jun
    Umeå University, Faculty of Science and Technology, Department of Mathematics and Mathematical Statistics.
    Effects of winter climate on delays of high speed passenger trains in Botnia-Atlantica region2021In: Journal of Rail Transport Planning & Management, ISSN 2210-9706, E-ISSN 2210-9714, Vol. 18, article id 100251Article in journal (Refereed)
    Abstract [en]

    Harsh winter climate can cause various problems for both public and private sectors in Sweden, especially in the northern part for railway industry. To have a better understanding of winter climate impacts, this study investigates effects of the winter climate including ice/snow precipitation on the performance of high speed passenger trains in the Botnia-Atlantica region. The investigation is done with train operational data together with simulated weather data fromthe Weather Research and Forecast model over January–February 2017.

    Two different measurements of the train performance are analysed. One is primary delay which measures the increment in delay in terms of running time within two consecutive measuring spots, the other is arrival delay which is the delay in terms of arrival time at each measuring spot compared to the schedule. Primary delay is investigated through a Cox model and the arrival delay is studied using a Markov chain model.

    The results show that the weather variables have impacts on the train performance. Therein temperature and humidity have significant impacts on both the occurrence of primary delay and the transition intensities between arrival delay and non-delay.

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  • 39.
    Wang, Jianfeng
    et al.
    Umeå University, Faculty of Science and Technology, Department of Mathematics and Mathematical Statistics.
    Granlöf, Markus
    Umeå University, Faculty of Science and Technology, Department of Mathematics and Mathematical Statistics.
    Yu, Jun
    Umeå University, Faculty of Science and Technology, Department of Mathematics and Mathematical Statistics.
    Effects of winter climate on high speed passenger trains in Botnia-Atlantica region2020Manuscript (preprint) (Other academic)
    Abstract [en]

    Harsh winter climate can cause various problems for both public and private sectors in Sweden, especially in the northern part for railway industry. To have a better understanding of winter climate impacts, this study investigates effects of the winter climate including atmospheric icing on the performance of high speed passenger trains in the Botnia-Atlantica region. The investigation is done with train operational data together with simulated weather data from the Weather Research and Forecast model over January - February 2017.

    Two different measurements of the train performance are analysed. One is cumulative delay which measures the increment in delay in terms of running time within two consecutive measuring spots, the other is current delay which is the delay in terms of arrival time at each measuring spot compared to the schedule. Cumulative delay is investigated through a Cox model and the current delay is studied using a Markov chain model.

    The results show that the weather factors have impacts on the train performance. Therein temperature and humidity have significant impacts on both the occurrence of cumulative delay and the transition probabilities between (current) delayed and non-delayed states.

  • 40.
    Wang, Jianfeng
    et al.
    Umeå University, Faculty of Science and Technology, Department of Mathematics and Mathematical Statistics.
    Mantas-Nakhai, Roberto
    Department of Computer Science, Electrical and Space Engineering, Luleå University of Technology, Luleå, Sweden.
    Yu, Jun
    Umeå University, Faculty of Science and Technology, Department of Mathematics and Mathematical Statistics.
    Statistical learning for train delays and influence of winter climate and atmospheric icing2023In: Journal of Rail Transport Planning & Management, ISSN 2210-9706, E-ISSN 2210-9714, Vol. 26, p. 13article id 100388Article in journal (Refereed)
    Abstract [en]

    This study investigated the climate effect under consecutive winters on the arrival delay of high-speed passenger trains. Inhomogeneous Markov chain model and stratified Cox model were adopted to account for the time-varying risks of train delays. The inhomogeneous Markov chain modelling used covariates weather variables, train operational direction, and findings from the primary delay analysis through stratified Cox model. The results showed that temperature, snow depth, ice/snow precipitation, and train operational direction significantly impacted the arrival delay. Further, by partitioning the train line into three segments as per transition intensity, the model identified that the middle segment had the highest chance of a transfer from punctuality to delay, and the last segment had the lowest probability of recovering from delayed state. The performance of the fitted inhomogeneous Markov chain model was evaluated by the walk-forward validation method, which indicated that approximately 9% of trains may be misclassified as having arrival delays by the fitted model at a measuring point on the train line. With the model performance, the fitted model could be beneficial for both travellers to plan their trips reasonably and railway operators to design more efficient and wiser train schedules as per weather condition.

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  • 41.
    Wang, Jianfeng
    et al.
    Umeå University, Faculty of Science and Technology, Department of Mathematics and Mathematical Statistics.
    Yu, Jun
    Umeå University, Faculty of Science and Technology, Department of Mathematics and Mathematical Statistics.
    Train performance analysis using heterogeneous statistical models2021In: Atmosphere, ISSN 2073-4433, E-ISSN 2073-4433, Vol. 12, no 9, p. 12article id 1115Article in journal (Refereed)
    Abstract [en]

    This study investigated the eect of harsh winter climate on the performance of high speed passenger trains in northern Sweden. Novel approaches based on heterogeneous statistical models were introduced to analyse the train performance in order to take the time-varying risks of train delays into consideration. Specically, stratied Cox model and heterogeneous Markov chain model were used for modelling primary delays and arrival delays, respectively. Our results showed that the weather variables including temperature, humidity, snow depth, and ice/snow precipitation have signicant impact on the train performance.

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  • 42.
    Westin, Jonas
    Umeå University, Faculty of Social Sciences, Centre for Regional Science (CERUM).
    Analys av generaliserade transportkostnader för användning i måluppföljning2017Report (Other academic)
    Abstract [sv]

    Trafikanalys har givit CERUM i uppdrag att utvärdera möjligheten att använda generaliseradetransportkostnader från Trafikverkets Samgodsmodell som en indikator i Trafikanalys årligauppföljning av de transportpolitiska målen. Arbetet utgör ett av flera underlag till Trafikanalysarbete med att besvara regeringsuppdraget (N2016/05490/TS) att se över transportpolitiskapreciseringar och lämna förslag till indikatorer för att följa upp de transportpolitiska målen.

  • 43.
    Westin, Jonas
    Umeå University, Faculty of Social Sciences, Centre for Regional Science (CERUM).
    Analys av kostnadsindex för generaliserade transportkostnader för Trafikanalys måluppföljning2020Report (Other academic)
    Abstract [sv]

    Trafikanalys har givit CERUM i uppdrag att utvärdera generaliserade godstransport- och logistikkostnader från Trafikverkets Samgodsmodell som en indikator i Trafikanalys årliga uppföljning av de transportpolitiska målen. Arbetet utgör ett av flera underlag till Trafikanalys arbete med att se över transportpolitiska preciseringar och lämna förslag till indikatorer för att följa upp de transportpolitiska målen.

    I denna rapport redovisas en analys av modellberäknade kostnadsindex uppdelat på läns- och kommunnivå för genomsnittliga godstransport- och logistikkostnader uppdelat på fyra olika klasser av varugrupper baserat på senaste basscenariot i Trafikverkets Samgodsmodell version 1.2 med basår 2017. En jämförelse görs även mellan kostnadsindex för Samgodsversion 1.2 för basåret 2017 och motsvarande kostnadsindex för basscenariot i föregående Samgodsversion modellversion 1.1.1 med basår 2012.

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  • 44.
    Westin, Jonas
    Umeå University, Faculty of Social Sciences, Centre for Regional Science (CERUM).
    Fördjupade godsflödesanalyser för Trafikverket region Nord och Mitt2016Report (Other academic)
    Abstract [sv]

    Denna rapport är framtagen och finansierad på uppdrag av Trafikverket Region Nord och Region Mitt. Syftet med rapporten har varit är att genomföra en fördjupad analys av godsflöden längs vägar, järnvägar och sjörutter i Trafikverkets region Nord och Mitt så som de beskrivs i Trafikverkets Samgodsmodell. Trafikverkets Samgodsmodell är central för Trafikverkets inriktnings- och åtgärdsplanering, vid skapandet av en lägesbild över godsflöden och godstransportefterfrågan i regionen är det därför viktigt att bygga arbetet utifrån denna modell. I ett tidigare projekt har en lägesbild över godstransportefterfrågan i Trafikverkets regioner Nord och Mitt baserat på data från Trafikverkets Samgodsmodell redovisats. Målsättningen med detta projekt har varit att fördjupa och analysera resultat från detta tidigare arbete.

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    CERUM Report 44-2016
  • 45.
    Westin, Jonas
    Umeå University, Faculty of Social Sciences, Centre for Regional Science (CERUM).
    Förslag på process för fortsatt arbete med regional systemanalys och länstransportplaner i Norrbotten och Västerbotten2015Manuscript (preprint) (Other academic)
  • 46.
    Westin, Jonas
    Umeå University, Faculty of Social Sciences, Centre for Regional Science (CERUM).
    Metoder för regional konsekvensanalys av förändrade hastighetsgränser2018Report (Other academic)
    Download full text (pdf)
    CERUM_Report_46_2018
  • 47.
    Westin, Jonas
    et al.
    Umeå University, Faculty of Social Sciences, Centre for Regional Science (CERUM). Umeå University, Faculty of Science and Technology, Department of Mathematics and Mathematical Statistics.
    Asplund, Disa
    Statens väg- och transportforskningsinstitut (VTI).
    Sjöfartens konkurrenskraft - Betydelsen av returtransporter2021Report (Other academic)
    Abstract [sv]

    Samgods är den nationella godsmodellen som på myndighets- och departementsnivå används för transportprognoser, kvantifieringar av effekter av åtgärder, policyanalyser och stråkanalyser för godstrafik. Modellering av sjöfart i Samgods sker idag på ett förenklat sätt genom fixa avgångs¬frekvenser mellan hamnar, utan möjlighet för modellen att lösa transportproblemet genom användning av distributionsslingor eller returtransporter. Syftet med detta projekt är att undersöka potentiella effekter av att införa slingor och returtransporter i en modell med en liknande struktur som Samgods. Projektet ska även ge förslag på hur slingor och returtransporter kan inkorporeras i kommande versioner av Samgods. Den modell som används i projektet är en vidare¬utveckling av LIFreM-modellen som utvecklades i det tidigare projektet ”Sjötransporter i modell och verklighet – betydelsen av samlastning, skal¬fördelar, frekvens, hastighet, lastbärare och slingor” som genomförts under 2016 - 2017.

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  • 48.
    Westin, Jonas
    et al.
    Umeå University, Faculty of Social Sciences, Centre for Regional Science (CERUM).
    de Jong, Gerard
    Significance.
    Vierth, Inge
    Swedish National Road and Transport Research Institute (VTI).
    Krüger, Niclas
    Swedish National Road and Transport Research Institute (VTI).
    Karlsson, Rune
    Swedish National Road and Transport Research Institute (VTI).
    Johansson, Magnus
    Transport Analysis.
    Baserunning - analyzing the sensitivity and economies of scale of the Swedish national freight model system using stochastic production-consumption-matrices2015Report (Refereed)
    Abstract [en]

    The purpose of the paper is to analyze how sensitive the Swedish national freight model system Samgods is to uncertainties in its production-consumption matrices (PC-matrices). This is done by studying how sensitive outputs from one of its key component, the logistics model, are to changes in the PC-matrices. This paper is, to our knowledge, the first attempt to analyze the sensitivity and economies of scale of a national freight transport model using Monte Carlo simulation. The results indicate that the logistics model is able to find new logistics solutions when larger demand volumes are assumed. Freight volumes are calculated to shift to sea transport. If the transport volume increases with one percent, the logistics cost per tonne is on average reduced by about 0.5 percent. Part of the cost reduction comes from increased consolidation of shipments due to larger transport volumes. There is also a positive correlation between total transport demand and the load factor for heavier lorries, trains and larger ships. Without empirical data and further analysis it is difficult to assess the estimated strength of the effect. Furthermore, the analysis indicates that it might be possible to reduce runtimes by removing small transport flows from the PC-matrices without affecting aggregate results too much.

  • 49.
    Westin, Jonas
    et al.
    Umeå University, Faculty of Social Sciences, Centre for Regional Science (CERUM).
    Forsgren, Andreas
    Infrastructure planning: a challenge for cross-border cooperation2015Conference paper (Other academic)
  • 50.
    Westin, Jonas
    et al.
    Umeå University, Faculty of Social Sciences, Centre for Regional Science (CERUM).
    Forsgren, Andreas
    Umeå University, Faculty of Social Sciences, Centre for Regional Science (CERUM).
    Infrastructure planning: A challenge for cross-border cooperation2014Report (Other academic)
    Abstract [en]

    The paper describes national infrastructure planning in Finland, Sweden and Norway as well as the tools and guidelines which are used for cost-receipts analysis at the national level. Special focus will be directed towards cross-border infrastructure and the extent to which the national planning process permits national and cross-border infrastructure projects to be compared on the same terms and conditions. Given that national and cross-border infrastructure projects cannot be compared on the same terms and conditions with existing evaluation methods, the risk of sub-optimal infrastructure allocations is immediate.

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