| 1. |
- Ivina, Daria, et al.
(författare)
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Lean Construction Principles and Railway Maintenance Planning
- 2020
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Ingår i: Proceedings of 28th Annual Conference of the International Group for Lean Construction (IGLC). - : International Group for Lean Construction. ; , s. 577-588
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Konferensbidrag (refereegranskat)abstract
- Lean construction principles have been successfully adopted in a variety of industries to increase project management quality. This paper addresses maintenance planning in Sweden and analyses its effectiveness in the framework of lean construction principles. To investigate the status and improvement potential of maintenance contractors’ performance, the study focuses on the detailed planning process, which is mainly the responsibility of contractors. A literature review, a data analysis and interviews were used to reveal the possible barriers to the adaptation of lean principles to the maintenance industry. The study presents a developed theoretical framework for the analysing maintenance processes in the perspective of lean construction principles. We found that the application of lean principles has the potential for improvements in the planning process, but there are some barriers to effective implementation, including a lack of knowledge about lean principles at contractors’ sites.
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| 2. |
- Ivina, Daria, et al.
(författare)
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Significance of the contractual relationship for the efficient railway maintenance project planning
- 2022
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Ingår i: Procedia Computer Science. - : Elsevier BV. - 1877-0509. ; 196, s. 920-926
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Tidskriftsartikel (refereegranskat)abstract
- Efficiently planned railway maintenance helps ensure reliable infrastructure and the proper functioning of its components. The Swedish Transport Administration delegates maintenance work to contractors through a tender process. This paper analyses differences in communication and collaboration in the planning and execution of maintenance under two contract types. A document review and interviews with 22 project managers identifies issues in planning and scheduling related to knowledge transfer at contractor companies, booking time for maintenance and lack of trust between contractors and the client. The results show how the two types of contracts are perceived differently by the parties to the contracts.
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| 3. |
- Jansson, Emil, et al.
(författare)
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Challenges of replacing train drivers in driverless and unattended railway mainline systems—A Swedish case study on delay logs descriptions
- 2023
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Ingår i: Transportation Research Interdisciplinary Perspectives. - 2590-1982. ; 21, s. 100875-100875
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Tidskriftsartikel (refereegranskat)abstract
- Currently, the challenges of driverless or unattended train operation have not been described in detail and are often grouped into one category. This paper contributes to filling a knowledge gap regarding the roles of the train driver about the potential use of automatic train operation (ATO) on high grade of automation (GoA) levels. The results contribute to a better understanding of the challenges with driverless or unattended train operation to support strategies on how to utilize ATO on a wider range of trains than is presently the case. We use the Swedish railway network as a case study and delay logs written by train dispatchers for 2019. Our research quantifies how often unplanned events occur in which the train driver is needed, and the role of the train driver in solving these problems. In addition to this we elaborate on existing GoA levels definitions and propose a revised model that highlights more aspects of the train drivers’ roles. We have identified six categories in which an action by the driver is required: Detect, Report, Inspect, Adjust, Manage passengers, and Respond to train orders. The study illustrates some of the challenges with driverless or unattended train operation, and points to the need to develop strategies not only for the driving aspects of ATO but also for the more general technical operational management of rolling stock in high GoA levels.
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| 4. |
- Jansson, Emil
(författare)
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Challenges with Driverless and Unattended Train Operations
- 2023
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Demand for transportation continues to increase, for both freight and passenger services. One of the most energy-efficient modes of transportation is rail. One solution to increase the attractiveness of rail transport is to introduce automatic train operation (ATO) with a high grade of automation (GoA). Driverless and unattended train operation could entail positive effects but would also bring challenges when removing the train driver. Thus, there is a need to understand the role of train drivers, especially in unplanned events. The main research objectiveis to understand the train driver roles during unplanned events and the frequency of such events. This thesis includes three papers to fulfill the research objective.This thesis studied delay logs and trackside sensor logs. A qualitative method, thematic analysis, was used to identify themes of the roles performed by train driver from the delay logs. The chi-square test statistical method was used to analyze these trackside sensor logs.Six main categories of tasks for train drivers were identified for unplanned events. Detect, Report, Inspect, Adjust, Manage passengers, and Respond to train orders. Each category was analyzed for each grade of automation by giving the responsibility for each category. The results highlight in a novel way the varied challenges between grade of automation in mainline systems. Detecting abnormalities was the most common task train drivers performed during unplanned events. Train drivers use four human senses to detect abnormalities: sight, hearing, touch, and smell. This indicates the need for onboard sensors. However, the real challenge is in processing all sensor data to gain anaccurate evaluation of any fault. One specific type of unplanned event in which the train driver is needed involves trackside sensor alarms. Freight trains are ten times more likely to trip an alarm than passenger trains. Alarms are more frequent in colder climate zones during winter months. These differences are statistically significant and indicate that not all lines and train types might be suitable for a high grade of automation.If driverless or unattended train operation will become a reality in future, many challenges must be met. This thesis gives deeper understanding of these challenges using a novel way to identify and quantify train driver tasks during unplanned events.
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| 5. |
- Jansson, Emil, et al.
(författare)
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The use of human senses by train drivers to detect abnormalities
- 2023
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Ingår i: TRA Lisbon 2022 Conference Proceedings Transport Research Arena. - : Elsevier BV. ; , s. 3650-3655
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Konferensbidrag (refereegranskat)abstract
- Driverless and unattended train operation is a foreseeable future. While many functions of the driver can be automatized and replaced but detecting abnormalities is more difficult to automate. This study investigates how train drivers detect abnormalities. The objective is to prepare the way for unattended train operation also for remote areas. Using disruption descriptions, written by train dispatchers, we have identified which senses are used by the train drivers and in which situations. Four of the human senses are used by train drivers to detect abnormalities: the visual, the auditory, the somatosensory, and the olfactory systems. The most used sense by the train drivers to detect abnormalities is the visual system. Before introducing driverless and unattended train operation, alternative tools for detecting abnormalities should be included based on the human senses.
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| 6. |
- Jansson, Emil, et al.
(författare)
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Trackside sensors in unattended train mainline systems : A case study of alarm logs from Sweden
- 2024
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Ingår i: 25th Euro Working Group on Transportation Meeting. - : Elsevier BV. ; , s. 151-157
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Konferensbidrag (refereegranskat)abstract
- Implementing unattended train operation on the mainline could make the railway more competitive by reducing operating costs since there will be no staff onboard the train. This will, however, lead to new challenges. One of those challenges is how to deal with manually controlling trackside sensor alarms. In this paper, we study all trackside sensor alarms (hotbox/hotwheel and wheel damage) in Sweden for one year (2019) to study their frequency and context. The results show that freight trains have 10 times higher frequency for alarms per train kilometer than passenger trains. There are statistically significant seasonal and climate zone differences. The highest frequency of trackside alarms occurs in wintertime in the colder climate zone. The results can be used in the development of unattended train operation support systems on the mainline.
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| 7. |
- Kadefors, Anna, Professor, 1962-, et al.
(författare)
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Relational contracting in Nordic construction – a comparative longitudinal account of institutional field developments
- 2024
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Ingår i: International Journal of Managing Projects in Business. - : Emerald Publishing. - 1753-8378 .- 1753-8386. ; 17:8, s. 22-46
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Tidskriftsartikel (refereegranskat)abstract
- Purpose: Relational contracting is increasingly being applied to complex and uncertain construction projects. However, it has proved hard to achieve stable performance and industry-level learning in this field. This paper employs an institutional perspective to analyze how legitimacy for relational contracting has been produced and challenged in Denmark, Finland, Norway and Sweden, including implications for dissemination and learning. Design/methodology/approach: A collaborative case study design is used, where longitudinal accounts of the developments in relational contracting over more than 25 years in four Nordic countries were developed by scholars based in each country. The descriptions are underpinned by literature sources from research, practice and policy. Findings: The countries share similar problem perceptions that have triggered the de-institutionalization of traditional contracting practices. Models and policies developed elsewhere are important sources of knowledge and legitimacy. Most countries have seen pendulum movements, where dissemination of relational contracting is followed by backlashes when projects fail to meet projected outcomes. Before long, however, relational contracting tends to re-emerge under new labels and in slightly new forms. Such a proliferation of concepts presents further obstacles to learning. Successful institutionalization is found to rely on realistic goals in combination with broad competence development at the organizational and industry levels. Practical implications: In seeking inspiration from other countries, policymakers should go beyond contract models to also consider strategies to manage industry-level learning. Originality/value: The paper provides a unique longitudinal cross-country perspective on the field of relational contracting. As such, it contributes to the small stream of literature on long-term institutional change in the construction sector.
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| 8. |
- Knutsen, Daniel, et al.
(författare)
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Capacity evaluation of ERTMS/ETCS hybrid level 3 using simulation methods
- 2024
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Ingår i: Journal of Rail Transport Planning & Management. - : Elsevier. - 2210-9706 .- 2210-9714. ; 30
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Tidskriftsartikel (refereegranskat)abstract
- This paper evaluates the capacity effect of ERTMS/ETCS Hybrid Level 3 (HL3, also known as Hybrid Train Detection, HTD) on a conceptual level by looking at a scenario with two trains and on a network level. Key performance indicators help evaluate the results of implementing HL3: headway for the conceptual model and capacity utilization and punctuality for the network level. The study uses the simulation tool RailSys for both levels. A case study on the interaction between two trains examines how various lengths of virtual blocks affect the performance indicator headway. The network scale simulations use a real-world infrastructure and a complete timetable. Two cases examine how the performance indicators capacity utilization and punctuality are affected by the share of Level 2 and Level 3 trains in a HL3 system. Results from the conceptual two-train interaction show that HL3 slightly improves the headway, but it is similar for varying virtual block lengths. The results from the network model indicate the share of Level 2 and Level 3 trains has minimal effect on punctuality and capacity utilization. However, we identified some factors influencing the HL3 capacity evaluation, like stations and switches on the line, that affect the potential capacity gains.
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| 9. |
- Knutsen, Daniel, et al.
(författare)
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Capacity evaluation of ERTMS/ETCS Hybrid Level 3 using simulation methods
- 2024
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Ingår i: Sammanställning av referat från Transportforum 2024. - Linköping : Statens väg- och transportforskningsinstitut. ; , s. 458-459
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- ERTMS/ETCS Hybrid Level 3 (HL3) was designed to achieve higher capacity and increase the robustness of the railway network cost-effectively. This study evaluates the capacity effect of HL3 on a conceptual level by looking at a scenario with two trains and on a network level. Key performance indicators help evaluate the results of implementing HL3: headway for the conceptual model, and capacity utilization and punctuality for the network level. With the implementation of HL3, two central variables influence the capacity: the length of Virtual Sub-Section (VSS) and the share of Level 2 (L2) and Level 3 (L3) trains in the network. For this purpose, we need to answer the following questions: What effects do different VSS lengths have on the performance indicators?How does the share of L2 and L3 trains in an HL3 system affect capacity?What are other key factors that influence HL3 capacity evaluations? The study uses the simulation tool RailSys, an integrated microscopic planning tool developed by RMCon. A case study on the interaction between two trains examines how various lengths of VSS affect the performance indicator headway. The network scale simulations use a real-world infrastructure and a complete timetable. Two cases examine how the performance indicators capacity utilization and punctuality are affected by the share of L2 and L3 trains in a HL3 system.
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| 10. |
- Kuipers, Ruben A., et al.
(författare)
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The passenger’s influence on dwell times at station platforms : a literature review
- 2021
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Ingår i: Transport Reviews. - : Informa UK Limited. - 0144-1647 .- 1464-5327. ; 41:6, s. 721-741
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Tidskriftsartikel (refereegranskat)abstract
- Dwell time delays, although small in nature, can accumulate to a large delay over the entire journey of a train. It is, however, difficult to precisely know the amount of time which is required at stations due to the inherent variance in human behaviour. Furthermore, planning practices do not seem to capture the dynamic nature of the dwell time process. The current literature review focusses on the influence that passengers have on the length and variance of dwell times at stations. More specifically, this study focusses on the underlying causes for the distribution of passengers along a platform while waiting for the train to arrive at the station and their behaviour during the boarding and alighting process. As part of this review, two databases were systematically searched, and backwards snowballing techniques were applied. To ensure the quality of the included literature, a systematic quality appraisal was carried out. The findings show that measures related to platform management and changes to train operations have the potential to play a substantial role in reducing the variance in dwell times, as well as improvements in the provision of information to travellers. Such measures also allow for a more solution-oriented approach. However, the actual benefits of such measures need further studying. The findings also show that the distribution of passengers and the behaviour of passengers during the boarding and alighting process are connected and should thus be addressed as a whole rather than separate aspects. The majority of the studies included in this review did, however, not focus on both elements in conjunction. There is thus a need for future studies into the effect of platform management measures where efforts must be made to better understand the impact of measures on both the behaviour and distribution of passengers.
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