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- Norrbin, Per, et al.
(författare)
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Infrastructure robustness for railway systems
- 2016
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Ingår i: International Journal of Performability Engineering. - 0973-1318. ; 12:3, s. 249-264
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Tidskriftsartikel (refereegranskat)abstract
- In the railway industry, most maintenance approaches are based on certain “specified conditions”, e.g., RAMS (Reliability, Availability, Maintainability and Safety) and Risk. But the reality is more complex. Instead of the assumed conditions, “unfavorable conditions” may occur from either natural or operational causes, where robustness can be an effective approach. To adequately consider “unfavorable conditions” and to reduce “uncertainties” in railway maintenance, this study conducts a holistic examination of railway infrastructure robustness. It gives an overview of robustness and discusses some relevant studies. It then develops a new road map for railway infrastructure robustness, including a novel definition and a new framework of robustness management, based on continuous improvement. It explores the opportunities of applying the road map to the infrastructure of railway systems and outlines some practical concerns and remaining challenges for future research. The results provide guidelines for other research into robust infrastructure in railway maintenance.
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| 3. |
- Norrbin, Per
(författare)
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Railway Infrastructure Robustness : Attributes, evaluation, assurance and improvement
- 2016
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- According to the European program Horizon 2020, multifaceted challenges in transportinfrastructure include 1) making infrastructure more resilient to keep pace with the increasing mobility needs; 2) reducing the impact of infrastructure on the environment;and 3) dealing with declining resources to maintain and upgrade transport infrastructure. New design and maintenance approaches must be developed to handle these issues, ascurrent methods are inadequate.In maintenance practices of railway infrastructure, most attention has been placed on RAMS (Reliability, Availability, Maintainability and Safety) study to meet asset safety and availability requirements. In Sweden, a popular development of the concept is RAM4S which incorporates supportability, sustainability, and security. However, the reality is more complex than these concepts suggest; various natural or operational uncertaintiescan cause “unfavourable” conditions requiring a quite different approach.Resilience studies can improve the ability of an infrastructure to withstand disturbances caused by uncertainties. To this point, most studies have considered extreme events,including natural events, like earthquakes or floods, and man-made events, like deliberateattacks on infrastructures. However, both naturally caused and operationally caused unfavourable conditions which do not belong to extreme events need to be studied as well. This represents a significant gap in the research.Robustness as a part of resilience has attracted much attention in recent years as it may be able to sufficiently consider those unfavourable conditions. In railway systems, however, robustness studies have mainly been aimed at timetable management to handle delays (including secondary delays) within the system. Yet according to statistics on total delays for the year 2015, from the follow-up system of the Swedish Transport administration (Trafikverket), LUPP, more than 30% of the root causes of delays are due to non-robustinfrastructures.To fill the above research gaps and support decision making of a railway infrastructure manager, the study described in the thesis conducts a holistic examination of railway infrastructure robustness considering its attributes, evaluation, assurance and improvement by investigating, exploring and developing new definitions and approaches. First, it develops a new road map for railway infrastructure robustness, including a novel definition and a framework. Its overview of robustness related topics results in a unique definition that identifies attributes of railway infrastructure robustness and clarifies the research boundaries between robustness and reliability, resilience, and risk. The study’s ground-breaking framework, named house of robustness management (HORM), is based on continuous improvement to support infrastructure robustness management in railway;HORM consists of robustness management goals and guidance, a continuous improvement process, and support systems through which assurance and improvement can be supported. Second, in addition to the qualitative evaluation of railway infrastructure robustness enabled by the road map, the study proposes a new quantitative evaluation approach by considering a dataset of “specified disturbance”, a corresponding “acceptable functionality”, and a dataset of weights of risk preference. Third, to apply railway infrastructure robustness to the development of sustainability, it provides a case study on energy efficiency optimisation in Sweden.This thesis consists of two parts. The first gives an introductory summary of the subjectand research, followed by a discussion of the appended papers, suggested extension of the research and conclusions. The second part consists of three appended papers. The first paper concerns the new road map including the definition and a framework. The second paper proposes a new quantitative evaluation approach for railway infrastructure robustness. The third paper is a case study on railway switches & crossings which will be further pursued under the topic of “green robustness”. The three subsequent papers develop the dependability improvement of railway infrastructure considering information logistics and risks, as well as maintenance cost.
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| 4. |
- Norrbin, Per, et al.
(författare)
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Tillförlitlighet och underhåll inom järnväg : Terminologi på svenska och engelska
- 2017
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Rapport (populärvet., debatt m.m.)abstract
- Denna rapport är ett delresultat ifrån FUD-projektet ’Begreppsapparat och kvalitetssäkrad information för bättre effektsamband inom järnvägar’. Syftet är att med hjälp av grundläggande och viktiga begrepp baserat på standarder göra en terminologisk ordlista för att öka samsynen och kunskaperna inom områdena förvaltning av tillgångar, tillförlitlighet och underhållsteknik.
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| 5. |
- Palmqvist, Carl-William, et al.
(författare)
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Satellite Monitoring of Railways using Interferometric Synthetic Aperture Radar (InSAR)
- 2021
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- There is over 15,600 km of track in the Swedish railroad network. This network is vital for the transportation of people and goods across the country. It is important that this network is monitored and maintained to ensure good function and safety. A tool for monitoring and measuring ground deformation over a large area remotely with high frequency and accuracy was developed in recent decades. This tool is known as Interferometric Synthetic Aperture Radar (InSAR), and is used by researchers, geo-technicians, and engineers.The purpose of this study has been to evaluate the use and feasibility of the InSAR technique for track condition monitoring and compare it to conventional track condition monitoring techniques. Malmbanan, which is primarily used to transport iron-ore from mines in Sweden to the ports of Luleå, Sweden and Narvik, Norway, is used as a case study for this project; specifically, the section between Kiruna and Riksgränsen. Coordinate matching of measurements from the provided Persistent Scatterer Interferometry (PSI) InSAR data and Optram data from survey trains were performed. Then measured changes over different time spans within the two systems were overlapped and classified with different thresholds to see if there is correlation between the two systems. An extensive literature review was also conducted in order to gain an understanding of InSAR technologies and uses.The literature review showed that there is a large potential and a quickly growing number of applications of InSAR to monitor railways and other types of infrastructure, and that the tools and algorithms for this are being improved. The case study, on the other hand, shows that it can be difficult to directly compare measurement series from different tools, each working on different resolutions in terms of both time and space. InSAR is thus not about to replace techniques such as those behind Optram (using measurement trains). Instead, the approaches offer complementary perspectives, each highlighting different types of issues.We find that InSAR offers a good way to identify locations with settlements or other types of ground motions. Especially transition zones between settlements and more stable ground can be challenging from a maintenance point of view and can clearly be identified and monitored using InSAR. With the rollout of national InSAR-data, and the large increase in data accessibility, we see a considerable potential for future studies that apply the technique to the railway area.
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| 6. |
- Stenström, Christer, et al.
(författare)
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Preventive and corrective maintenance : cost comparison and cost–benefit analysis
- 2016
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Ingår i: Structure and Infrastructure Engineering. - : Informa UK Limited. - 1573-2479 .- 1744-8980. ; 12:5, s. 603-617
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Tidskriftsartikel (refereegranskat)abstract
- Maintenance can represent a significant portion of the cost in asset intensive organisations, as breakdowns have an impact on the capacity, quality and cost of operation. However, the formulation of a maintenance strategy depends on a number of factors, including the cost of down time, reliability characteristics and redundancy of assets. Consequently, the balance between preventive maintenance (PM) and corrective maintenance (CM) for minimising costs varies between organisations and assets. Nevertheless, there are some rules of thumb on the balance between PM and CM, such as the 80/20 rule. Studies on the relationship between PM and CM in practice are rare. Therefore, PM and CM costs are studied in this article by analysing historical maintenance data. A case study of rail infrastructure historical data is carried out to determine the shares of PM and CM, together with a cost–benefit analysis (CBA) to assess the value of PM. The results show that the PM represents 10% to 30% of the total maintenance cost when user costs, i.e. train delays, are included as a CM cost. The CBA shows the benefit of PM is positive with a benefit–cost ratio at 3.3. However, the results depend on the inclusion/exclusion of user costs, besides individual organisational parameters.
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| 7. |
- Söderholm, Peter, et al.
(författare)
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Information logistics for continuous dependability improvement
- 2014
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Ingår i: Journal of Quality in Maintenance Engineering. - 1355-2511 .- 1758-7832. ; 20:3, s. 249-261
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Tidskriftsartikel (refereegranskat)abstract
- Purpose – The purpose of this paper is to describe an information logistic framework for continuous dependability improvement that is applied within Sweden to improve the operational availability performance of the railway system.Design/methodology/approach – The applied study approach is a case study of the Swedish iron ore transports, described from the perspectives of the infrastructure manager and the operator of the rolling stock. Qualitative data were collected through interviews, workshops and document studies, while quantitative data were collected through databases. As a framework for analysis, international standards within the dependability area were applied. Finally, the conclusions of the study were verified by key informants.Findings – Information logistics provides methodologies and technologies to support continuous dependability improvement through monitoring of the operational availability performance and its included aspects of reliability performance, maintainability performance and maintenance support performance.Practical implications – The operational availability performance of technical systems is crucial to provide a quality of services that fulfils the requirements of stakeholders. Hence, continuous dependability improvement is necessary to keep pace with increasing stakeholder requirements and ongoing system degradation to enable stakeholder satisfaction. The framework is based on best practices and international standards.Originality/value – The proposed framework includes an integration of methodologies and technologies from the information technology and dependability management areas that considers both railway infrastructure and rolling stock.
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