1. |
- Adolphson, Marcus, 1966-, et al.
(author)
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Impact on urban form by the localization of railway stations : Evidence from Sweden
- 2019
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In: Cities. - : Elsevier. - 0264-2751 .- 1873-6084. ; 95
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Journal article (peer-reviewed)abstract
- Since the 1990s a number of new railway stations have been established in Sweden on new or rerouted lines, while other stations have been reconstructed at their original locations. Some stations were located in urban surroundings, others in semi-urban or peripheral locations depending on the trade of between regional speed, and local urban circumstances. The urban form consequences depending on station localisation of these transport infrastructure investments are nonetheless unknown. In order to provide a basis for future planning, this research aims to provide knowledge on urban form consequences of relocating railway stations. 13 stations were selected in a case study. Changes in urban densities from 1993 to 2013 were analysed by a combination of kernel techniques and estimation of monocentric density models. Stations within an urban and semi-urban environments show strong agglomeration tendencies. Within peripheral environments, the urban development was unclear or even negative. In an urban environment, the location of the station still attracted more urban resources compared to the location of the urban density centre. These findings should be understood in the light of a market-oriented socio-economic context since 1990th influencing the planning system and the development of urban form.
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2. |
- Djordjevic, Boban, et al.
(author)
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An optimisation-based digital twin for automated operation of rail level crossings
- 2024
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In: Expert systems with applications. - : Elsevier BV. - 0957-4174 .- 1873-6793. ; 239
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Journal article (peer-reviewed)abstract
- Railway level crossings (LCs), as the intersection of road and rail transport, are the weak points in terms of safety, as they are used by different modes of transport. The safety level at LCs can therefore be affected by the behaviour of the users. However, the level of safety can also be affected by failures and errors in the operation of LC equipment. Apart from safety, errors and failures of the LC devices can lead to longer waiting times for road users. As the volume of traffic on rail and road increases, so does the risk that the level of safety will decrease. The increase in traffic volume via LC leads to higher traffic volume on the road and more frequent trains on the rail, which leads to longer waiting times for road users on the LCs. The longer waiting times can disrupt the traffic flow, especially during peak hours when the growing volume of traffic on road and rail increases road user dissatisfaction. Moreover, in the era of Industry 4.0 and Digital Rail, new digital and automated technologies are being introduced to improve rail performance and competitiveness. These technologies are aligned with the LCs and are intended to ensure the efficient operation of LC and the efficient use of LCs by conventional trains as well. To achieve this, a concept is needed that simultaneously monitors and visualises the operation of LC in real time, identifies potential faults and failures of the LC equipment, and updates and monitors the proper operation of LC based on the historical data and information of the operation of LC according to the road traffic volume and the characteristics of the rail traffic and trains. Therefore, in this study, a digital twin system (DT) for rail LC was initiated and built as a concept that can meet the above requirements for proper LC operation in real time. DT of LC includes all components of LC and communication between them to synchronise the operation of LC according to the real-time requirements. The DT system is able to optimise the operation time of LC by monitoring the operation of LC and collecting data to ensure efficient use of LC and reduce unnecessary waiting time for road users. In this paper, the operation time of LCs on Swedish and Taiwanese railways was compared using the developed level crossing optimisation model (OLC). Since the introduction of new signalling concepts requires an improvement of LC operating characteristics and their design, the operating strategies were modelled using the OLC model. The results of the work show that the optimal values of LC operation time are different for the case studies investigated. The replacement of track circuits as detection devices and the introduction of balises can also positively influence the operation time, as well as increasing the speed of trains via LCs. However, due to the formulation of the OLC model, the impact of a longer train length on the operation of LC is not recognised. The OLC model can be used to estimate the real-time operation time of LC under different traffic conditions as well as the impact of different changes and extensions of LC.
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3. |
- Djordjevic, Boban, et al.
(author)
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Determinants of autonomous train operation adoption in rail freight : knowledge-based assessment with Delphi-ANP approach
- 2023
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In: Soft Computing - A Fusion of Foundations, Methodologies and Applications. - : Springer Nature. - 1432-7643 .- 1433-7479. ; 27:11, s. 7051-7069
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Journal article (peer-reviewed)abstract
- Railways are the backbone of complex and multimodal transport systems in Europe. To secure a larger share of the transport market and attract existing and future freight customers, further improvement in services is required. To achieve this goal, the use of new technologies in the era of railway automation and digitalization is required. Automatic train operation (ATO) in rail transport is considered a promising solution for providing cost-effective rail products. In this study, we define ATO as autonomous train operation and the feasibility of ATO deployment in rail freight is investigated. For this purpose, a knowledge-based approach is introduced to identify opportunities, problems, and the most appropriate grade of automation in rail freight. In a multi-stage process, Delphi questionnaires were combined with the analytic network process (ANP) method to investigate, define, and weight the determinants for ATO deployment. The final phase of the survey estimated the potential costs and drivers for different grades of automation. The results show that, in addition to the positive impacts of ATO, there are numerous challenges and risks that need to be analysed before ATO is implemented. In addition, the Delphi-ANP approach was used to identify the key determinants for decision-making prior to ATO implementation and the most viable alternative based on them. Investment cost, level of safety, energy saving, and reliability of management system are the most important determinants for the decision to implement ATO. The results of this study can effectively support rail infrastructure managers and operators in strategic planning and decision-making for ATO implementation in rail freight.
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4. |
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Framtidsblick på järnvägens kapacitet
- 2023
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Editorial proceedings (pop. science, debate, etc.)abstract
- Attraktiv tågtrafik för framtidenRegionala tågtrafiksystem 1990-2020Resande och tågtrafikVilken resandeutveckling kan vi förvänta oss?Spårtrafik ger tillgänglighet: 1 timmes tågrestid från Stockholm CPotentiell tillgänglighet till arbetsplatser: Från Eskilstuna med kollektivtrafikHur får man bilister att ta tåget istället?Kapacitet vid blandad resp. separerad trafik: Antal tåg i en riktning (vid dubbelspår)Var behövs kapacitet?Järnvägsprojekt = tillgänglighetDigitalisering – för ökad kapacitetSnabba godståg – minskade hastighetsskillnaderMer gods på järnvägMer kapacitet betyder:•Punktligheten ökar, färre förseningar•Bättre marknadsanpassning av tidtabellen, fler tåg •Korta res- och transporttider, inga onödiga tillägg•Lägre trafikeringskostnader, högre intäkter•Mer attraktiv tågtrafik – ger ökat resande och ökade godstransporter•Nöjda resenärer och godskunder
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5. |
- Fröidh, Oskar, 1965-, et al.
(author)
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Intervjuer med intressenter i långväga resandeprognoser : Delrapport i Förstudie kring etablering av forskningsprojekt för prognosmetodik
- 2023
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Reports (other academic/artistic)abstract
- Syftet med denna rapport är att redovisa resultat och slutsatser från en enkätstudie med intressenter inom prognosmodeller för långväga resande (resande över 100 km) som genomfördes i september 2023.Många enkätsvar är i linje med att en framtida modell behövs för att göra ungefär samma saker som idag, att den nuvarande modellen har brister, och att bra data att skatta modellen är svåra att få tag på. Mer intressant är förslag på förändringar i modellen eller dess användning. En sådan är hur vi ska definiera en långväga resa. Det finns andra, alternativa definitioner än ”längre än tio mil” som har mer med resans ärende, start- och målpunkt eller andra egenskaper att göra.Det finns två kommentarer, i synnerhet, med potential att påverka modellansatsen. Den första är att en prognos för ett vardags- eller årsmedeldygn inte nödvändigtvis är det mest intressanta. På vissa ställen är årsvariationen stor och dimensionerande, till exempel för turismresor, medan på andra kan dygns- och veckovariation vara viktig att förstå.Målbaserade scenarier och backcasting nämns också. En annan typ av modell än dagens Sampers skulle kunna bidra på ett bättre sätt till att hitta lämpliga åtgärder och hjälpa till med att hitta lösningar på problem snarare än att fokusera på att räkna på effekterna av åtgärderna. Det stora arbetet är att underhålla indata och framtidsscenarier av nätverk och markanvändning. Vi skulle kunna verka för att ha en gemensam bas av indata, lämpligen också öppen för extern forskning och utveckling, som sedan kan användas till olika modeller beroende på vilken fråga som ställs.När det gäller kompetens tolkar vi intervjusvaren som att den behöver stärkas både bland användare så att resultaten kan genereras och tolkas med förståelse av orsakssamband, och bland modellutvecklare. Samtidigt upplever en del respondenter att systemet är tungarbetat och det används i praktiken mest för ett relativt fåtal scenarioanalyser. Ibland skulle det nog vara mer användbart med ett prognosverktyg att testa idéer eller alternativa åtgärder i ett tidigt skede. Det finns också svar som antyder en efterfrågan på en modell som kan bidra tydligare till problemlösning och målstyrning. Dagens mer prognosinriktade modellansats kan användas till sådant, men inte på ett naturligt sätt.Vår slutsats av intervjustudien är att den har gett oss insikter om användarnas uppfattningar och behov. För att utveckla framtidens prognosmetodik behöver vi komplettera med kunskap om nya metoder och dess egenskaper i en litteraturstudie.
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6. |
- Fröidh, Oskar, 1965-
(author)
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Introduction of regional high speed trains : A study of the effects of the Svealand line on the travel market, travel behaviour and accessibility
- 2003
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Doctoral thesis (other academic/artistic)abstract
- The Svealand line opened in 1997 and the services areoperated with regional high speed trains. While the Svealandline was being built, the slow trains that had been inoperation on the old railway between Eskilstuna and Stockholm(a distance of 115 km) were replaced by buses with a highfrequency of service. In a case study of the effects of regional high speed trainservices, field surveys were made of residents and publictransport passengers along the line, and in a reference centreof population, before and after the Svealand line opened.Changes in knowledge, valuations and travel behaviour have beenanalysed, as have changes in accessibility. The supply and thedemand for regional journeys by car, bus and train have alsobeen examined. The results show that the Svealand line has meant anincrease of up to seven times in regional travel by railcompared to the old railway between Eskilstuna and Stockholm,and the market share has risen from 6% to 30%. Those who travelmost are people who have access to a car at times. Habitualmotorists, on the other hand, account for the largest increasein travel by public transport. In areas close to the railwaystations in Strängnäs and Eskilstuna new patterns ofcar ownership, travel behaviour, choice of transport mode andchoice of destination have been found since the regional highspeed trains began operating on the Svealand line. Commuting towork has also shown a marked increase. Travelling times arevalued highly and especially motorists value the high speedtrain mode of transport highly. Poorer train services and busservices are not attractive to motorists other than as areserve alternative to their own cars. A general conclusion is that the regional high speed trainservices have had a major impact on the travel market, travelbehaviour and accessibility. The improved accessibility toStockholm in particular is especially noticeable amongresidents close to the railway stations. Keywords:The Svealand line, high speed trains, regionaltravel, travel behaviour, choice of transport mode,accessibility
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7. |
- Fröidh, Oskar, 1965-, et al.
(author)
-
Utbud och priser i persontrafik på järnväg 2022 : Utveckling i Sverige 1990-2022
- 2022
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Reports (other academic/artistic)abstract
- Syftet med föreliggande rapport är att följa upp utvecklingen av utbud och priser inom persontrafik på järnväg med ett urval sträckor i Sverige och till grannländerna som en del av Transportstyrelsens marknadsövervakning.För de flesta järnvägslinjerna med persontrafik har utbud och biljettpriser studerats för en relation mellan två orter. På några viktigare relationer har insamlingen utökats med även kommersiella flyg- och busslinjer som konkurrerar med tåg för att få en helhetsbild av resemarknaden. Data om utbudet har samlats in en helgfri onsdag i mars eller oktober, beroende på förutsättningarna respektive år. 2022 var den planerade resdagen, eller huvudmätdagen, onsdagen den 5 oktober och priserna motsvarar bokning en vecka innan avresa. Målet har varit att representera en typisk vardag utan störning av helger eller semesterperioder som kan påverka resandet.Persontrafiken på järnväg har trendmässigt ökat sedan 1990 och har mer än dubblerats på 30 år. Efterfrågan har växt i takt med utbudsförbättringar genom snabbare tåg, tätare turer och attraktiva priser. Coronapandemin 2020 innebar dock ett kraftigt avbräck i utvecklingen. Under 2022 har en återhämtning skett och fritidsresandet med tåg blev i ungefär samma storleksordning som det tidigare toppåret 2019, medan tjänsteresorna ligger lägre.Den uppåtgående trenden i biljettpriser 2022 kan förklaras av den ökade efterfrågan på framför allt fritidsresor som gör det möjligt för järnvägsföretagen att ta igen förlorade intäkter från coronapandemiåren 2020-2021. Den begränsade tillgången till billiga biljetter kan dock ha medfört att flera resenärer får betala mer för sina tågresor. Det ger en större effekt för resenärerna, särskilt vid senare bokningar, än prishöjningar inom respektive biljettpriskategori som ingår i undersökningen.Flygutbudet har inte återhämtat sig lika väl som tåget sedan coronapandemin, och ligger 2022 generellt på ungefär halva antalet avgångar jämfört med 2019. Däremot sker en priskonkurrens med tåg på de största reserelationerna Göteborg−Stockholm, Malmö−Stockholm och Umeå−Stockholm, med billiga flygbiljetter som beroende på avgång kan vara lägre än tillgängliga biljetter för tågresa. Inte heller bussutbudet har återhämtat sig och det är svårt för buss att konkurrera såväl i restid som i pris med lågprisbiljetter för tåg och flyg på de större relationerna.Sammanfattningsvis har 2022 präglats av sviter av coronapandemin, särskilt personalbrist, men även andra problem inom järnvägen som försenad tidtabellsplanering. Efterfrågan är relativt svag på tjänsteresor men stark på privatresor, i nivå med det tidigare toppåret 2019. Ett flertal biljettpriser har stigit men annars ligger utbudet nästan i nivå med det tidigare toppåret 2019.
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8. |
- Högdahl, Johan, 1989-, et al.
(author)
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A combined simulation-optimization approach for minimizing travel time and delays in railway timetables
- 2019
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In: Transportation Research Part B. - : PERGAMON-ELSEVIER SCIENCE LTD. - 0191-2615 .- 1879-2367. ; 126, s. 192-212
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Journal article (peer-reviewed)abstract
- Minimal travel time and maximal reliability are two of the most important properties of a railway transportation service. This paper considers the problem of finding a timetable for a given set of departures that minimizes the weighted sum of scheduled travel time and expected delay, thereby capturing these two important socio-economic properties of a timetable. To accurately represent the complex secondary delays in operational railway traffic, an approach combining microscopic simulation and macroscopic timetable optimization is proposed. To predict the expected delay in the macroscopic timetable, a surrogate function is formulated, as well as a subproblem to calibrate the parameters in the model. In a set of computational experiments, the approach increased the socio-economic benefit by 2-5% and improved the punctuality by 8-25%.
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9. |
- Högdahl, Johan, 1989-
(author)
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A Simulation-Optimization Approach for Improved Robustness of Railway Timetables
- 2019
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Licentiate thesis (other academic/artistic)abstract
- The timetable is an essential part for the operations of railway traffic, and its quality is considered to have large impact on capacity utilization and reliability of the transport mode. The process of generating a timetable is most often a manual task with limited computer aid, and is known to be a complex planning problem due to inter-train dependencies.These inter-train dependencies makes it hard to manually generate feasible timetables, and also makes it hard to improve a given timetable as new conflicts and surprising effects easily can occur.As the demand for railway traffic is expected to continue grow, higher frequencies and more saturated timetables are required. However, in many European countries there is also an on-going public debate on the punctuality of the railway, which may worsen by increased capacity utilization. It is therefore also a need to increase the robustness of the services. This calls for increased precision of both the planning and the operation, which can be achieved with a higher degree of automation.The research in this thesis is aimed at improving the robustness of railway timetables by combining micro-simulation with mathematical optimization, two methods that today are used frequently by practitioners and researchers but rarely in combination. In this research a sequential approach based on simulating a given timetable and re-optimizing it to reduce the weighted sum of scheduled travel time and predicted average delay is proposed. The approach has generated promising results in simulation studies, in which it has been possible to substantially improve the punctuality and reduce the average delays by only increasing the advertised travel times slightly. Further, the results have also indicated a positive socio-economic benefit. This demonstrates the methods potential usefulness and motivates further research.
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10. |
- Högdahl, Johan, 1989-, et al.
(author)
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Combining Optimization and Simulation to Improve Railway Timetable Robustness
- 2017
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Conference paper (peer-reviewed)abstract
- The Train Timetabling Problem (TTP) is the problem of finding the timetable that utilizes the infrastructure as efficient as possible, while satisfying market demands and operational constraints. As reliability is important to passengers it is important that timetables are robust. In this paper we propose a method that combines optimization and simulation to find the timetable that minimizes the travel times and maximizes the expected punctuality. The core method consists of iteratively re-optimizing a bi-objective mixed integer sequencing timetable model, where both planned travel time and simulated delays are taken into account. Each generated timetable is validated and re-evaluated using the micro-simulation tool RailSys. The advantage of the method is that it captures both the uncertainty of a timetable at the planning stage and the validity of the generated timetable. The method is evaluated on a unidirectional track section of the Western Main Line in Sweden and shows promising results for future research.
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