Change search
Refine search result
1 - 14 of 14
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Rows per page
  • 5
  • 10
  • 20
  • 50
  • 100
  • 250
Sort
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
Select
The maximal number of hits you can export is 250. When you want to export more records please use the Create feeds function.
  • 1. Niska, Stefan
    et al.
    Schunnesson, Håkan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Nyström, Birre
    Causes of EMC disturbance on the railway: a study of recurring faults in the signal box at Oxmyran station in Sweden2009In: International Journal of COMADEM, ISSN 1363-7681, Vol. 12, no 2, p. 20-29Article in journal (Refereed)
    Abstract [en]

    Failure reporting systems in the railway industry are reliant on correct reporting into the system, so that the right information may be send back to the user. This information is needed for correct decision-making in the maintenance process. For failure due to electromagnetic disturbance a correct classification can be very difficult to make in the field, with limited time available for the analysis of failure causes. The Swedish Railway Administration (Banverket) has a problem in a signal box at Oxmyran Station, where faults are reported frequently. The wide variation in the reported causes of the disturbance of the electromagnetic compatibility makes it very difficult to pinpoint the real causes of the events that lead to failure. In this paper, a large number of causes are investigated, discussed and dismissed as reasons for the large number of faults at Oxmyran. Measurements on site, however, show that the electromagnetic interference is much higher at Oxmyran than at the reference station at Ore Alv. The main purpose of this study was to investigate the probable source and the subsequent sequence of events that result in faults that break the RC circuit at Oxmyran.

  • 2.
    Nyström, Birre
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    A methodology for measuring the quality of deviation reporting: applied to railway delay attribution2008In: International Journal of Quality & Reliability Management, ISSN 0265-671X, E-ISSN 1758-6682, Vol. 25, no 7, p. 656-673Article in journal (Refereed)
    Abstract [en]

    Purpose - The purpose of this paper is to describe a methodology based on vignettes and its application to measure the consistency of railway delay attribution, in order to report on experiences of using the methodology in this context. Design/methodology/approach - A survey is used to ask personnel performing delay attribution about how they would report the delays described in the vignettes of the survey. The development, application and analysis of the survey are thoroughly described here. Findings - The methodology proved useful for measuring the consistency of delay attribution. Research limitations/implications - The methodology also supports a further investigation of the accuracy of delay attribution systems. Practical implications - A survey similar to the one presented here can be used by railways to estimate the accuracy of their delay attribution systems, as well as to continuously improve them. Changes to computer software and training will improve the delay attribution system under study. Originality/value - By investigating current delay attribution practices using surveys based on vignettes, drawbacks of the current delay attribution system can be identified and remedied. The methodology is applicable to a wide class of deviation attribution applications.

  • 3.
    Nyström, Birre
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Aspects of improving punctuality: from data to decision in railway maintenance2008Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The increasing demand for transportation and sustainability makes railways attractive. The ongoing deregulation of state-owned railways means that many new organisations are entering the railway sector. Hence, reducing railway delays is increasingly important to many stakeholders, including passengers, freight customers, train operating companies, railway infrastructure managers and society in general. Therefore, the study of punctuality and its improvement is essential. The purpose of the research presented in this thesis is to explore and describe information and requirements related to railway punctuality in order to support systematic improvements. The focus is on delay causes related to infrastructure maintenance. To fulfil the stated purpose, punctuality requirements, availability concepts, failure and delay data, as well as maintenance decisions, have been studied via theoretical and empirical approaches. Data was collected through interviews, document studies, archival analysis, observations and experiments. It is found that punctuality requirements and performance are currently expressed in many, hardly commensurable, ways. Hence, it is difficult to compare punctuality data from different railways. This is further complicated by the fact that delay attribution is inconsistently performed. It is also found that there is a lack of data on train traffic and infrastructure, for example, causes of delays. Although the consistency regarding ranking of decision-making criteria is rather high, the consistency of maintenance decisions is rather low. In addition, there are many interacting causes affecting punctuality, including infrastructure, timetable, rolling stock, weather and personnel. It is also found that even though unpunctuality might be explained by unavailability of some parts of the railway system, the concept of availability is not well-established and agreed upon within the railway sector. Based on the research findings, it is proposed that punctuality should be treated as the extent to which an event takes place when agreed, for example, the agreement between a passenger and a train operating company concerning the arrival of a train at a certain time. A number of availability measures for railway are also proposed, partly based on analogies to the power industry. Furthermore, the developed and applied methodologies, based on vignettes and the Analytic Hierarchy Process (AHP), are proposed to support punctuality improvements. To summarise, based on the results of this research, it is possible to improve data collection and recording, select suitable indicators and increase the awareness of the grounds on which decisions are made, all of which contribute to improved punctuality.

  • 4.
    Nyström, Birre
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Enkät om rapportering av förseningar2006Report (Other academic)
    Abstract [sv]

    Dessa fyra olika versioner av en enkät om rapportering av förseningar ingår i projektet "Bättre punktlighet genom effektivt underhåll". De är avsedda att fyllas i av personal som rapporterar förseningar inom tågtrafiken med programmen TFÖR och/eller Basun.

  • 5. Nyström, Birre
    Improved punctuality: a freight train study2005In: Abstracts of the Eighth International Conference "Maintenance & Renewal of Permanent Way; Power & Signalling; Structures & Earthworks": Railway engineering 2005 / [ed] M. C. Forde, Engineering Technics Press , 2005, p. 19-Conference paper (Other academic)
    Abstract [en]

    A procedure to systematically find actions to improve punctuality concerning railway infrastructure, and giving the greatest improvement is illustrated. The transports of a company producing steel slabs in one factory and performing rolling in another are investigated. Reliable transports between plants are crucial to market competitiveness. The transport chain of steel slabs is described and the distance by train is investigated regarding punctuality, transportation times and causes for lack of punctuality. Pros and cons of the procedure employed and ways to improve punctuality are discussed, including infrastructure maintenance.

  • 6. Nyström, Birre
    Punctuality and railway maintenance2005Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Long and frequent train delays, striking many periodically make headlines. The question is raised: what might be done about it? The on-going deregulation of the Swedish railway, with more actors entering the market, contributes to the question's topicality. In this thesis, problems and symptoms concerning punctuality are described and analysed. Herein, punctuality is defined as the extent to which an event takes place when agreed, for example the agreement between passengers and the company selling the ticket, considering the event that the train arrives at a certain time. The terminology in use on punctuality-related entities is floating. Causes for unpunctuality are related to the infrastructure, locomotives, wagons and personnel. Herein, primarily failures related to infrastructure are discussed. Maintenance, i.e. correcting and preventing failures, together with the track, rolling stock, weather, driver, other personnel and the timetable determine how good the punctuality will be. To the ore and steel transports studied it is more important to limit the lengths of the transport times, rather than having high punctuality, i.e. adherence to timetable. Generally, for freight transports it is difficult to give an estimation of the cost for unpunctuality. To find the root cause of a delay is vital, as is identification of symptoms and triggering events, in order to be able to carry out appropriate actions. Often the information needed to do so is lacking in the Ofelia database for infrastructure failures. Comparisons between regions or over time are complexified by the varying policies on how failure coding is to be performed. To improve punctuality by learning from others is made more difficult by e.g. different countries employing different ways of denoting punctuality. In the transport chain of post in Norway, terms related to punctuality varied even more among stakeholders. They considered being informed on estimated time of arrival as important, but getting this information was, despite this, not among the quantified goals. Few requirements were quantified, despite this often being simple to do. The consequences of failure are important to consider, not only e.g. the number of failures. Studying the variation in transport time on different line sections might help in identifying problems, because coding of delays shorter than five minutes is not carried out in the Swedish railway. Such causes of delay include low contact wire voltage, minor problems with locomotives and slippery rails due to leaves on the track. Disadvantageously, this variation is masked in the case of heavy trains or steep and curvy lines. In a studied maintenance organisation, the indicators of maintenance measured the result of the entire maintenance process. In order to manage each sub process better, it is more advantageous to measure the performance of them individually. Considering the specific sub process that decides which maintenance actions are to be carried out, it only uses expenses for the action itself when deciding, not resulting future costs and punctuality. The indicators focus on measuring past performance, not on facilitating planning for the future. A design of information systems facilitating information usage from different functions of the organisation would facilitate informed decisions. Information concerning technology, traffic and economy need to be integrated.

  • 7. Nyström, Birre
    Punktlighet2005Report (Other academic)
    Abstract [en]

    An important goal for railway traffic is for the trains to be punctual. Here, punctuality and its relation to maintenance are discussed. The report introduces and is a part of the project "Improved punctuality by effective maintenance".Punctuality is defined as the extent to which an event takes place when agreed. Some different ways of defining punctuality are discussed in regard to trains, aeroplanes and brewing. The ways different countries define punctuality and related terms are shown. The literature on national economic benefit is summarised.A model for the impact of maintenance on punctuality is put forward.Within the northern region zone of the railway infrastructure manager Banverket, the indicators of maintenance measured the result of the entire maintenance process. However, in order to permit better control of the maintenance process, the performance of each sub process requires to be measured.

  • 8.
    Nyström, Birre
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Use of availability concepts in the railway system2009In: International Journal of Pedagogy, Innovation and New Technologies, ISSN 0973-1318, E-ISSN 2392-0092, Vol. 5, no 2, p. 103-118Article in journal (Refereed)
    Abstract [en]

    This paper explores and describes indicators related to availability in the railway system. Examples of indicators include train punctuality and condition of track. The paper presents losses to the stakeholders, measured by the indicators. Indicators in Banverket (Swedish Rail Administration) and railway literature are presented. Indicators used in the electric power industry are also presented, as these offer good analogies from which to develop additional railway indicators. The indicators found in the literature, but not in Banverket, include travel time variation, slack and wagons. Indicators found by analogy to the power industry concern passengers, traffic work not delivered and how to subtract the effects of adverse weather. A classification of availability indicators is also suggested.

  • 9.
    Nyström, Birre
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Karlsson, Stefan
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Industrial Organisation.
    Description of railway delays: a study from the views of the stakeholders2006In: Condition Monitoring and Diagnostic Engineering Management: COMADEM 2006 ; proceedings of the 19th international congress, Luleºa, Sweden, 12 - 15 June 2006 / [ed] Uday Kumar, Luleå: Luleå tekniska universitet, 2006, p. 701-710Conference paper (Refereed)
    Abstract [en]

    The wish to improve quality of railway transport is facilitated by systematic feedback. Systematically describing delays and their causes is essential in improving punctuality. In this paper, requirements on a delay attribution system are discussed and analysed, in view of the current restructuring of the Swedish system. A freight train operating company, a p assenger train company and a maintenance contractor are interviewed in order to learn what features are considered important by them. Principles of delay attribution systems are discussed and suggestions for improvements are given.

  • 10. Nyström, Birre
    et al.
    Kumar, Uday
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Analysis of train delay information2003In: Congress proceedings: 2003 WCRR, the World Congress on Railway Research : 28 September - 1 October 2003, Edinburgh International Conference Centre, Edinburgh, Scotland, UK, Edinburgh, 2003, p. 253-261Conference paper (Refereed)
  • 11. Nyström, Birre
    et al.
    Söderholm, Peter
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Improved railway punctuality by effective maintenance: a case study2005In: Advances in Safety and Reliability: proceedings of the European Safety and Reliability Conference (ESREL 2005), Tri City (Gdynia - Sopot - Gdansk), Poland, 27 - 30 June, 2005 / [ed] Krzysztof Kolowrocki, Leiden: Balkema Publishers, A.A. / Taylor & Francis The Netherlands , 2005, p. 1487-1491Conference paper (Refereed)
    Abstract [en]

    A railway has many different requirements, such as safety and punctuality. The purpose of this studywas to explore and describe howmaintenance can contribute to improved punctuality. In an industry branch that is becoming more open, as is the case in Norway where this study was undertaken, it is important to have clear requirements and performance measures. This study has focused on railway stakeholders and their requirements regarding punctuality, the measures employed, and the traceability between requirements, goals, and measurements. Linking the end customer's punctuality requirements to reliability of the track is illustrated. The requirements flow is presented as well as a discussion about its pros and cons. The results of the study can be applied in order to compare different designs of maintenance to fulfil punctuality requirements. The information flow and the measures currently used are not entirely suitable concerning feedback and usefulness for managing availability and thus maintenance

  • 12. Nyström, Birre
    et al.
    Söderholm, Peter
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Improving railway punctuality by maintenance: a case study2005Report (Other academic)
    Abstract [en]

    A railway has many different requirements, such as safety and punctuality. The purpose of this study was to explore and describe how maintenance can contribute to improved punctuality. In an industry branch that is becoming more open, as is the case in Norway where this study was undertaken, it is important to have clear requirements and performance measures. This study has focused on railway stakeholders and their requirements regarding punctuality, the measures employed, and the traceability between requirements, goals, and measurements. Linking the end customer's punctuality requirements to reliability of the track is illustrated. The requirements flow is presented as well as a discussion about its pros and cons. The results of the study can be applied in order to compare different designs of maintenance to fulfil punctuality requirements. The information flow and the measures currently used are not entirely suitable concerning feedback and usefulness for managing availability and thus maintenance.

  • 13. Nyström, Birre
    et al.
    Söderholm, Peter
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Selection of maintenance actions using the analytic hierarchy process (AHP): decision-making in railway infrastructure2010In: Structure and Infrastructure Engineering, ISSN 1573-2479, E-ISSN 1744-8980, Vol. 6, no 4, p. 467-479Article in journal (Refereed)
    Abstract [en]

    A methodology for prioritising between different maintenance actions in the railway infrastructure is presented. The consistency of the prioritisation and the feasibility of the applied methodology are investigated. Criteria describing the diverse effects of maintenance are developed and presented to track managers, together with a set of maintenance actions that are specific for each track manager. Then, the analytical hierarchy process (AHP) is used to obtain preferences for the criteria and for the different actions. The track managers roughly agree on the prioritisation of criteria. However, the discrepancies between the results of the two ways employed to elicit the preferences for the actions are rather large. The track managers consider it easy to understand the rationale of the AHP and to enter their preferences. It is proposed that preferences are recorded as they are in this paper, in order to document the rationale of the decisions and to facilitate mutual learning among decision-makers and over time.

  • 14.
    Söderholm, Peter
    et al.
    Banverket.
    Nyström, Birre
    NSB.
    The analytic hierarchy process (AHP) for decision-making and expert judgement in railway infrastructure maintenance2009In: IRSC 2009, Båstad, Sweden, 2009Conference paper (Refereed)
    Abstract [en]

    Decision-making and expert judgement are two vital parts within safety and risk management, e.g. regarding: analyses of frequencies and consequences in risk analysis; risk tolerability decisions in risk evaluation and decision-making in risk reduction and control. There are a number of formal methodologies to elicit expert judgement and support decision-making. These methodologies contribute to inter-subjectivity, transparency and traceability of performed judgements and decisions, which in turn support continuous improvement and risk reduction. Examples of these methodologies are: Delphi methodology; paired comparison; category ranking and absolute probability judgements. This paper describes an application of the Analytic Hierarchy Process (AHP) to obtain preferences for strategic railway infrastructure criteria, such as safety and punctuality, and for different infrastructure maintenance actions from track managers in Sweden. The application of the AHP methodology was supported by a software tool, which facilitated recording, calculation and presentation of the track managers' preferences. The track managers consider it easy to understand the rationale of the AHP and to enter their preferences with the aid of a computer and the software tool. It is proposed that the preferences are recorded as in this paper, to document the rationale of performed decisions and to facilitate mutual learning among decision-makers and over time.

1 - 14 of 14
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf