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  • 1.
    Anandika, Rayendra
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Stenström, Christer
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Lundberg, Jan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Non-destructive measurement of artificial near-surface cracks for railhead inspection2019Inngår i: Insight (Northampton), ISSN 1354-2575, E-ISSN 1754-4904, Vol. 61, nr 7, s. 373-379Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This paper delivers a study involving the inspection of artificial surface cracks with depths ranging from 0.25-2.5 mm from the surface and with a crack angle of 30°, which is a typical angle for surface cracks in railheads. The inspections were conducted using three different techniques: phased array ultrasonics, single-element ultrasonics and alternating current potential drop (ACPD). For the ultrasonic techniques, the study focused on employing either longitudinal or shear wave signals. In the railway industry, shallow surface cracks in railheads are caused by rolling contact fatigue (RCF). In this study, artificial defects were made, allowing the authors to explore the extent to which the ultrasonic measurement techniques can detect such defects. The negative effect of a dead zone near to the surface in the ultrasonic tests was reduced by using a wedge attachment. A discussion on the extent to which the techniques can be used in field tests was also provided. The most important result is that shallow cracks ranging from 0.25-2.5 mm were successfully characterised with acceptable accuracy. The 2.5 mm-deep crack can be measured with an accuracy of 0.8% using a 20 MHz single-element probe and with an accuracy of 3.5% using a 5 MHz phased array (64 elements, 0.6 mm pitch). The characterisations were performed using a filtering method that was developed in this study.

    1675605

  • 2.
    Berges, Luis
    et al.
    Department of Design Engineering and Manufacturing, University of Zaragoza.
    Galar, Diego
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Stenström, Christer
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Qualitative and quantitative aspects of maintenance performance measurement: a data fusion approach2013Inngår i: International Journal of Strategic Engineering Asset Management (IJSEAM), ISSN 1759-9733, E-ISSN 1759-9741, Vol. 1, nr 3, s. 238-252Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The measurement of maintenance performance is often faced with a lack in knowledge about the real function of the maintenance department within organisations, and consequently appropriate targets from the global mission and vision are absence. Measurement metrics are not adapted to real needs, which have a strong human factor; nor is there a roadmap of the amount of data to be collected, their processing or how they are used in decision making. This article proposes a model where qualitative and quantitative methods are combined to complement the advantages of both.

  • 3.
    Eriksson, Kjell
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Material- och solidmekanik.
    Stenström, Christer
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Homogenization of the 1D Peri-static/dynamic Bar with Constant Micromodulus2020Inngår i: ISSN 2522-896XArtikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Because of the nonlocal interparticle forces inherent in peridynamics, surface, boundary, and end effects appear in 3D, 2D and 1D body problems, respectively. In certain situations, the effect is seen as a disturbance, and various efforts, mostly centering on 2D and 1D problems, have been made to reduce it. A simple method has been derived to remove the end effects in a 1D body by homogenizing the body. When a certain body type, common in practice, is homogenized, its linear elastic behavior, independent of the interparticle force range and with a finite number of material points, in the limit infinite, is identical to that of a corresponding classical continuum mechanics body.

  • 4.
    Famurewa, Stephen Mayowa
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Stenström, Christer
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Asplund, Matthias
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Galar, Diego
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Kumar, Uday
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Composite indicator for railway infrastructure management2013Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The assessment of efficiency and effectiveness of past maintenance decisions and actions is an essential element in maintenance process. The significance of this is not only limited to communicating the value contribution of maintenance to overall business objectives but also to drive maintenance for improvement and towards excellence. However the existence of numerous maintenance result areas and many operational level indicators often lead to distributed information that is not in a suitable format required to support decision making. This paper motivates the use of fuzzy logic approach to aggregate selected indicators to appreciate the information bit distributed in each indicator. The selected indicators include measures related to safety, comfort, punctuality, availability and reliability aspects of maintenance. Linguistic description and fuzzy sets are developed for each of the indicators which are regarded as input parameters. Also domain experts are employed to develop inference rules for the aggregation process. The methodology of using fuzzy inference system for aggregating maintenance performance indicators is demonstrated with selected line sections of Trafikverket (Swedish Transport Administration). The resulting composite indicator gives a reliable quantification of the health condition of the asset and performance of maintenance within the period under consideration. This can be easily communicated and benchmarked within the organization of the infrastructure manager.

  • 5.
    Famurewa, Stephen Mayowa
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Stenström, Christer
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Asplund, Matthias
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Galar, Diego
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Kumar, Uday
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Composite indicator for railway infrastructure management2014Inngår i: Journal of Modern Transportation, ISSN 2095-087X, E-ISSN 2196-0577, Vol. 22, nr 4, s. 214-224Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The assessment and analysis of railway infrastructure capacity is an essential task in railway infrastructure management carried out to meet the required quality and capacity demand of railway transport. For sustainable and dependable infrastructure management, it is important to assess railway capacity limitation from the point of view of infrastructure performance. However, the existence of numerous performance indicators often leads to diffused information that is not in a format suitable to support decision making. In this paper, we demonstrated the use of fuzzy inference system for aggregating selected railway infrastructure performance indicators to relate maintenance function to capacity situation. The selected indicators consider the safety, comfort, punctuality and reliability aspects of railway infrastructure performance. The resulting composite indicator gives a reliable quantification of the health condition or integrity of railway lines. A case study of the assessment of overall infrastructure performance which is an indication of capacity limitation is presented using indicator data between 2010 and 2012 for five lines on the network of Trafikverket (Swedish Transport Administration). The results are presented using customised performance dashboard for enhanced visualisation, quick understanding and relevant comparison of infrastructure conditions for strategic management. This gives additional information on capacity status and limitation from maintenance management perspective.

  • 6.
    Fecarotti, Claudia
    et al.
    University of Nottingham.
    Heubach, Justin
    Strukton Rail Bv.
    Kirwan, Andy
    Network Rail Infrastructure Ltd.
    Samson, Henk
    Strukton Rail Bv.
    Stenström, Christer
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Requirements and Initial Concept for an Asset Management Framework2017Rapport (Annet vitenskapelig)
    Abstract [en]

    This document constitutes the first issue of Deliverable D6.2 ‘Requirements and initial concept for an asset management framework’ in the framework of the project titled ‘Innovative Intelligent Rail’ (Project Acronym: In2Rail; Grant Agreement No 635900).

    This document has been prepared to provide the requirements and initial concept of a comprehensive framework for performance prediction, modelling and decision support for railway asset management, taking into account UIC asset management (AM) guidelines, rail infrastructure performance and constraints on resources and the supply chain. Two objectives guide the work: developing a key performance indicator (KPI) decision framework and defining a framework for performance prediction, modelling and decision support.

    Based on interviews and a study of previous work, including In2Rail D6.1, a KPI decision framework has been constructed, fully compliant with UIC AM guidelines, and an adapted KPI definition guide has been applied to two case studies. Specifically, the KPI definition guide has been used to exemplarily define availability KPI and risk matrix KPI in the context of rail transportation, using 36 questions to define the indicators and 10 questions to verify them. The KPIs are demonstrated using infrastructure managers’ (IMs) records of operation and maintenance.

    The developed framework constitutes a comprehensive modelling structure for describing, analysing, and optimising asset management decisions on a whole-life, whole-system basis. It defines a systematic approach to analysing the effects of any intervention plan and produces performance, risk and cost profiles that can be used as decision support. The framework will facilitate the assessment and development of intervention plans in three planning stages: strategic, tactical and operational. In this sense, the framework is fully compliant with ISO 55001, complementary to the UIC AM framework, and aligned with the Intelligent Asset Management System (IAMS) developed in In2Smart leverabel D2.1.

  • 7.
    Galar, Diego
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Parida, Aditya
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Kumar, Uday
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Stenström, Christer
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Berges, Luis
    Manufacturing Engineering and Advanced Metrology Group, Aragon Institute of Engineering Research (13A), University of Zaragoza.
    Maintenance metrics: a hierarchical model of balanced scorecard2011Inngår i: 2011 IEEE International Conference on Quality and Reliability: ICQR 2011 : Bangkok, 14 September 2011-17 September 2011, Piscataway, NJ: IEEE Communications Society, 2011, s. 67-74Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The system of performance measurement of maintenance function should cover all processes related to it within the organization. There must be an interconnection between the different indicators, so the numbers can be interpreted in order to reach a good conclusion for decision making. This premise implies a hierarchy of indicators needed in a dual way. First, it will require maintenance indicators to be segmented according to the areas of influence for the rest of the organization, posed by interactions with finance department, human resources, purchasing, and, of course, with production in the seeking of compliance with corporate objectives. Simultaneously, these indicators correspond to different levels in the organization and therefore they will be segmented according to the hierarchical position of end users.

  • 8.
    Galar, Diego
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Peters, Ralph
    Maintenance Excellence Institute.
    Berges, Luis
    Manufacturing Engineering and Advanced Metrology Group, Aragon Institute of Engineering Research (13A), University of Zaragoza.
    Stenström, Christer
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Kumar, Uday
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Composite indicators in asset management2012Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Composite indicators are formed when individual indicators are compiled into a single index. A composite indicator should ideally measure multidimensional concepts which cannot be captured by a single index. Since asset management is multidisciplinary, composite indicators would be helpful. The paper describes a method of monitoring a complex entity in a processing plant. In this scenario, a plurality of use indices and weighting values are used to create a composite use index from a combination of lower level use indices and weighting values. Each use index contains status information on one aspect of the lower level entities, and each weighting value corresponds to one lower level entity. The resulting composite indicator can be a decision-making tool for asset managers.Keywords – Indicator, aggregation, KPI, performance, hierarchy, DSS

  • 9.
    Galar, Diego
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Stenström, Christer
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Parida, Aditya
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Kumar, Rupesh
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Berges, Luis
    University of Zaragoza.
    Human factor in maintenance performance measurement2011Inngår i: IEEE International Conference on Industrial Engineering and Engineering Management (IEEM), Piscataway, NJ: IEEE Communications Society, 2011, s. 1569-1576Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The maintenance performance measurement is often faced with a lack in knowledge about the real function of the maintenance department within organizations, and consequently the absence of appropriate targets emanating from the global mission and vision. These facts bring about metrics not adapted to the real needs, which has a strong load of human factor and without a roadmap of the amount of data to be collected, their processing and use in decision making. This article proposes a model where qualitative and quantitative methods are combined in order to complement advantages and disadvantages of them both.

  • 10.
    Juntti, Ulla
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Asplund, Matthias
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Ripke, Burchard
    Lundwall, Björn
    Parida, Aditya
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Stenström, Christer
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Famurewa, Stephen Mayowa
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Kent, Stephen
    Glebe, Filip
    Nissen, Arne
    AUTOMAIN: D4.1 Improvement analysis for high performance maintenance and modular infrastructure2013Rapport (Annet vitenskapelig)
  • 11.
    Juntti, Ulla
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Parida, Aditya
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Stenström, Christer
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Famurewa, Stephen Mayowa
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Asplund, Matthias
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Nissen, Arne
    Ripke, Burchard
    Lundwall, Björn
    AUTOMAIN: D4.2 Optimised maintenance activities like, grinding, tamping and other maintenance processes2013Rapport (Annet vitenskapelig)
  • 12.
    Juntti, Ulla
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Stenström, Christer
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Famurewa, Stephen Mayowa
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Eriksson, Kristina
    Trafikverket.
    Parida, Aditya
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Increasing market credibility through continuous vulnerability reduction: A3.5, WP32013Rapport (Annet vitenskapelig)
  • 13.
    Khan, Saad Ahmed
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Lundberg, Jan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Stenström, Christer
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Carry distance of top-of-rail friction modifiers2018Inngår i: Proceedings of the Institution of mechanical engineers. Part F, journal of rail and rapid transit, ISSN 0954-4097, E-ISSN 2041-3017, Vol. 232, nr 10, s. 2418-2430Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Rail issues such as corrugation, rolling contact fatigue, noise and wear have been increasing with the increase in railway traffic. The application of top-of-rail friction modifiers (TOR-FMs) is claimed by their manufacturers in the railway industry to be a well-established technique for resolving the above-mentioned issues. There are various methods for applying friction modifiers at the wheel–rail interface, among which stationary wayside systems are recommended by TOR-FM manufacturers when a distance of a few kilometres is to be covered. TOR-FM manufacturers also claim that by using wayside equipment, the TOR-FM can be spread over a minimum distance of 3 km, over which it maintains a coefficient of friction of µ = 0.35 ± 0.05. To determine the carry distance of TOR-FMs, some researchers use tribometers to measure the coefficients of friction. However, moisture and deposits from the environment and trains can alter the top-of-rail friction and give a misleading indication of the presence of a friction modifier. Therefore, the coefficient of friction itself is not a clear indicator of the presence of TOR-FMs. In the present study, cotton swabs dipped in a mixture of alcohol and ester were used to collect surface deposits (a third body) from both the wheel and rail at various distances from the point of application. Subsequently, the third body collected on the cotton swab was analysed using an energy dispersive X-ray analysis. The results have shown that the maximum carry distance of TOR-FMs on the top of the rail is limited to 70 m when using a TOR-FM from one manufacturer and to 450 m when using a TOR-FM from another manufacturer. The carry distance on the contact band of the wheel is limited to 100 m and 340 m. The friction modifier on the edges of the contact band was detected over a distance of up to 3 km; however, this will not minimise the damage or friction at the wheel–rail interface.

  • 14.
    Khan, Saad Ahmed
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Lundberg, Jan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Stenström, Christer
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Life cycle cost analysis for the top-of-rail friction-modifier application: A case study from the Swedish iron ore line2020Inngår i: Proceedings of the Institution of mechanical engineers. Part F, journal of rail and rapid transit, ISSN 0954-4097, E-ISSN 2041-3017Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The application of top-of-rail friction modifiers (TOR-FMs) is claimed by their manufacturers as a well-established technique for minimising the damages in the wheel–rail interface. There are various methods for applying friction modifiers at the wheel–rail interface, among which stationary wayside systems are recommended by TOR-FM manufacturers when a distance of a few kilometres is to be covered. An on-board system is recommended when an area of many kilometres has to be covered and focus is more on particular trains. Trafikverket in Sweden is considering the implementation of the TOR-FM technology on the iron ore line. Directly implementing such technology can be inappropriate and expensive, because the life cycle cost of a TOR-FM system has never been assessed for the conditions of the iron ore line. In the present study, the life cycle cost is calculated for wayside and on-board application systems, by taking inputs from the research performed on iron ore line. The present research has taken the iron ore line as a case study, but the results will be applicable to other infrastructure with similar conditions. The results have shown that the wayside equipment is economically unfeasible for the iron ore line. In this case, the life cycle cost increases by 4% when the friction modifier is applied on all curves with a radius smaller than 550 m and by 19% when the friction modifier is applied on all curves with a radius smaller than 850 m. The on-board system used in this study is shown to be economically feasible, as it has a significantly lower operation and maintenance cost than the wayside equipment. The reduction in the maintenance (grinding and rail replacement) cost when the cost of the friction modifier application is added is 27% when the friction modifier is applied on curves with a radius smaller than 550 m and 23% when the friction modifier is applied on curves with a radius smaller than 850 m.

  • 15.
    Khan, Saad Ahmed
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Persson, Ingemar
    AB DEsolver, Östersund, Sweden.
    Lundberg, Jan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Stenström, Christer
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Prediction of the effects of friction control on top-of-rail cracks2018Inngår i: Proceedings of the Institution of mechanical engineers. Part F, journal of rail and rapid transit, ISSN 0954-4097, E-ISSN 2041-3017, Vol. 232, nr 2, s. 484-494Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Rolling contact fatigue is a major problem connected with railway tracks, especially in curves, since it leads to highermaintenance costs. By optimising the top-of-rail friction, the wear and cracks on the top of the rail can eventually bereduced without causing very long braking distances. There are several research articles available on crack prediction,but most of the research is focused either on rail without a friction modifier or on wheels with and without frictioncontrol. In the present study, in order to predict the formation of surface-initiated rolling contact fatigue, a range offriction coefficients with different Kalker’s reduction factors has been assumed. Kalker’s reduction factor takes care ofthe basic tendency of creepage as a function of the traction forces at lower creepage. The assumed range covers possiblefriction values from those for non-lubricated rail to those for rail with a minimum measured friction control on the top ofthe rail using a friction modifier. A fatigue index model based on the shakedown theory was used to predict thegeneration of surface-initiated rolling contact fatigue. Simulations were performed using multi-body simulation, forwhich inputs were taken from the Iron Ore line in the north of Sweden. The effect of friction control was studiedfor different curve radii, ranging from 200 m to 3000 m, and for different axle loads from 30 to 40 tonnes at a constanttrain speed of 60 km/h. One example of a result is that a maximum friction coefficient (m) of 0.2 with a Kalker’s reductionfactor of 15% is needed in the case of trains with a heavy axle load to avoid crack formation.

  • 16.
    Khan, Saad Ahmed
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Persson, Ingemar
    AB DEsolver, Östersund.
    Lundberg, Jan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Stenström, Christer
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Prediction of top-of-rail friction control effects on rail RCF suppressed by wear2017Inngår i: Wear, ISSN 0043-1648, E-ISSN 1873-2577, Vol. 380-381, s. 106-114Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Rolling contact fatigue (RCF) and wear, two major deterioration processes, limit the lifetime of rails. These deterioration processes are even more severe on the curves of tracks used by heavy haul trains. Because wear is a material removing process, it can suppress the formation of RCF (also known as surface initiated cracks). In railways, cracks have a higher risk of instigating a catastrophic failure than wear; hence, it is comparatively better to have wear than to have cracks. By controlling the top-of-rail friction, both of these deteriorating processes can be reduced to enhance the lifetime of rails. In order to achieve these possible advantages, the infrastructure manager of the Swedish railway is planning to implement a top-of-rail friction control technology on the iron ore line in northern Sweden wherein RCF is a major problem on the curves. The present study uses a damage index model in a multi-body simulation software and predicts the probability of RCF formation with suppressing effect of wear for different friction control values. The effect of friction control is simulated on curve radii ranging from 200 to 3,000 m and axle loads ranging from 30 to 40 t at a constant train speed of 60 km/h. Findings show that on a very sharp circular curve, radius < 300 m, RCF can be eliminated without friction control due to the high wear rate. On moderate curves, 300 < radius < 1,000 m, a friction coefficient (µ) of, at most, 0.3 with a Kalker's coefficient of, at most, 30% is required to avoid RCF

  • 17.
    Kumar, Uday
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Galar, Diego
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Parida, Aditya
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Stenström, Christer
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Maintenance audits using balanced scorecard and maturity model2011Inngår i: Maintworld, ISSN 1798-7024, E-ISSN 1799-8670, nr 3, s. 34-40Artikkel i tidsskrift (Annet vitenskapelig)
    Abstract [en]

    There is increasing interest in the use of maintenance performance measurement (MPM) and the possibility of using the maintenance audits for benchmarking metrics. This article proposes a methodology for simple measurement, one that accepts the indicators used on a scorecard with four perspectives and is hierarchized according to organizational level. The maintenance audit will evaluate the degree of fulfillment of objectives and the degree of satisfaction obtained from each of those perspectives. It will provide a clear picture of the current status of maintenance organization and the success of implemented policies taking into account the maintenance maturity model, i.e, the logical evolution of the maintenance function in the company.

  • 18.
    Kumar, Uday
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Galar, Diego
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Parida, Aditya
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Stenström, Christer
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Berges, L.
    University of Zaragoza.
    Maintenance performance metrics: a state of the art review2011Inngår i: MPMM 2011: Maintenance Performance Measurement & Management: Conference Proceedings / [ed] Diego Galar; Aditya Parida; Håkan Schunnesson; Uday Kumar, Luleå: Luleå tekniska universitet, 2011, s. 3-34Konferansepaper (Fagfellevurdert)
    Abstract [en]

    This paper provides an overview of research and developments in the measurement of maintenance performance. It considers the problems of various measuring parameters and comments on the lack of structure in, and references for, the measurement of maintenance performance.The main focus is to determine how value can be created for organizations by measuring maintenance performance, looking at such maintenance strategies as condition based maintenance, reliability centered maintenance, e-maintenance etc. In other words, the objectives are to find frameworks or models that can be used to evaluate different maintenance strategies and determine the value of these frameworks for an organization.The paper asks the following research questions:- What approaches and techniques are used for Maintenance Performance Measurement (MPM) and which MPM techniques are optimal for evaluating maintenance strategies?- In general, how can MPM create value for organizations, and more specifically, which system of measurement is best for which maintenance strategy?The body of knowledge on maintenance performance is both quantitative and qualitative based. Quantitative approaches include economic and technical ratios, value-based and balanced scorecards, system audits, composite formulations, and statistical and partial maintenance productivity indices. Qualitative approaches include human factors, amongst others. Qualitative-based approaches are adopted because of the inherent limitations of effectively measuring a complex function such as maintenance through quantitative models. Maintenance decision makers often come to the best conclusion using heuristics, backed up by qualitative assessment, supported by quantitative measures. Both maintenance performance perspectives are included in this overview.

  • 19.
    Kumar, Uday
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Galar, Diego
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Parida, Aditya
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Stenström, Christer
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Berges, Luis
    University of Zaragoza.
    Maintenance performance metrics: a state-of-the-art review2013Inngår i: Journal of Quality in Maintenance Engineering, ISSN 1355-2511, E-ISSN 1758-7832, Vol. 19, nr 3, s. 233-277Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Purpose - This paper provides an overview of research and development in the measurement of maintenance performance. It considers the problems of various measuring parameters and comments on the lack of structure in and references for the measurement of maintenance performance. The main focus is to determine how value can be created for organizations by measuring maintenance performance, examining such maintenance strategies as condition-based maintenance, reliability-centred maintenance, e-maintenance, etc. In other words, the objectives are to find frameworks or models that can be used to evaluate different maintenance strategies and determine the value of these frameworks for an organization.Design/methodology/approach - A state-of-the-art literature review has been carried out to answer the following two research questions. Firstly, what approaches and techniques are used for maintenance performance measurement (MPM) and which MPM techniques are optimal for evaluating maintenance strategies? Secondly, in general, how can MPM create value for organizations and, more specifically, which system of measurement is best for which maintenance strategy?Findings - The body of knowledge on maintenance performance is both quantitatively and qualitatively based. Quantitative approaches include economic and technical ratios, value-based and balanced scorecards, system audits, composite formulations, and statistical and partial maintenance productivity indices. Qualitative approaches include human factors, amongst other aspects. Qualitatively based approaches are adopted because of the inherent limitations of effectively measuring a complex function such as maintenance through quantitative models. Maintenance decision makers often come to the best conclusion using heuristics, backed up by qualitative assessment, supported by quantitative measures. Both maintenance performance perspectives are included in this overview.Originality/value - A comprehensive review of maintenance performance metrics is offered, aiming to give, in a condensed form, an extensive introduction to MPM and a presentation of the state of the art in this field.

  • 20.
    Norrbin, Per
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik. Sweco Rail.
    Stenström, Christer
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Tillförlitlighet och underhåll inom järnväg: Terminologi på svenska och engelska2017Rapport (Annet (populærvitenskap, debatt, mm))
    Abstract [sv]

    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.

  • 21.
    Parida, Aditya
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Juntti, Ulla
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Stenström, Christer
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Famurewa, Stephen Mayowa
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Capacity Enhancement through Optimized Maintenance of Railway Networks2014Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Rail traffic has increased manifold during the last decade. This development and the need for shift transportation from road to rail to decrease CO2 emission, creates a challenge for the railway industry to improve capacity in the network. The challenge is to do more effective inspection and maintenance in less time. An EU project ‘AUTOMAIN’ was initiated to optimize and automate maintenance and inspection activities with introduction of new planning and scheduling tools and methodologies. The project looked into reducing the maintenance possession time by around 40%. The project aim was to; adopt best practices from other industries in maintenance optimization, developing novel track inspection approaches for freight routes. The scope was for in-train measuring and self-inspecting switch, researching and assessing innovations that can improve the effectiveness and efficiency of large scale inspection and maintenance processes with a scope on track and switch maintenance, track inspection; developing key technologies that will drive the development of modular infrastructure design, and developing a new maintenance planning and scheduling tool to optimize the maintenance activities, taking account of the benefits brought about by other improvements in this project.The Consortium composition covers the railway maintenance and inspection field like; infrastructure managers, contractors, train operating companies, railway component industry, research organizations, small and medium enterprises (SMEs) and railway industry related organizations. In this paper, the authors have tried to summarize the methodology and results achieved in this project and how it has achieved the reduced maintenance possession time for higher railway traffic movements.

  • 22.
    Parida, Aditya
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Juntti, Ulla
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Stenström, Christer
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Famurewa, Stephen Mayowa
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Asplund, Matthias
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Rantatalo, Matti
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Arasteh Khouy, Iman
    Project: Augmented Usage of Track by Optimisation of Maintenance, Allocation and Inspection of railway Networks2011Annet (Annet (populærvitenskap, debatt, mm))
  • 23.
    Parida, Aditya
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Kumar, Uday
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Galar, Diego
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Stenström, Christer
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Performance measurement and management for maintenance: A literature review2015Inngår i: Journal of Quality in Maintenance Engineering, ISSN 1355-2511, E-ISSN 1758-7832, Vol. 21, nr 1, s. 2-33Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Purpose:The purpose of this paper is to provide a literature review of the performance measurement in maintenance. The authors aim to discuss the background and development of the performance measurement for maintenance, besides defining the concept of performance measures for maintenance and the frameworks developed.Design/methodology/approach:A detailed and extensive literature search and study was undertaken by the authors on the concept and definition of performance measurement, performance indicators, maintenance performance indicators and various performance frameworks. The history and theory of performance measurement over different phases of business and technological developments have been critically examined and analysed in this review paper. Findings:This paper reviews and presents the different performance indicators (PIs) and performance measurement (PM) frameworks like; balanced scorecard, performance prism, performance pyramid and performance matrix etc, and identifies their characteristics and shortcomings. After considering related issues and challenges, frameworks and approaches for the maintenance performance measurement (MPM) are also presented, where the emerging techniques like; e-maintenance have also been discussed amongst others. More and more industries are applying the balanced and integrated MPM frameworks for their competitive survivability and sustainability.Practical implications:The concept, issues and approaches considered for the MPM frameworks can be adapted by the practicing managers, while trying to define and develop an MPM framework for the operation and maintenance activities. The considerations of the advantages and limitations of different frameworks can provide insights to the managers for implementation. Originality/value:Some literature reviews on MPM and MPM frameworks are available today. This paper makes an attempt to provide a detailed and relevant literature review, besides adding value in this new and emerging area.

  • 24.
    Parida, Aditya
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Stenström, Christer
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Asset performance evaluation: A recipe for success or failure2016Inngår i: Proceedings for the COMADEM 2016, 2016Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Abstract.The prevailing economicdownturn, looming global recession, vola-tile energy and asset prices with emerging technology for prescriptive analytics and increasing budgetary cuts have compelled the companies to manage its en-gineering assets competitively for survival and growth. As per international standard ISO 55001:2014, performance evaluation is fundamental to asset man-agement system (AMS). Asset maintenance performance measurement and management (AMPM) is a recognized process and best practice for supporting sustainability and return on investment.It is hard for an organization to improve the present level of performance of the engineering assets without measurement. Therefore, all functions including units and processes of the organization need to be built and developed as per as-set management principles, such as; ISO 55000 series standard. The challenges in AMPM are to prepare a strategic road map from top management level to the operational level through a link and effect model for identifying and developing key performance indicators (KPI). These KPIs are broken down to measures which are used for monitoring and controlling the unplanned downtime with in-creased reliability, availability, maintainability and safety. Other challenges are to define and develop methods for right data collection through condition moni-toring and big data analytics, beside management for knowledge management. eMaintenance is required for remote data collection, storage, analysis and deci-sion making. The KPIs and indicators will be used for developingcomposite indicators (CI) for bench marking the performance with the best in the industry, besides verifying the return on investment.The author has discussed the various compulsions and challenges associated with asset performance evaluation (APE) for AMPM for the organization. Once the AMPM fundamentals and recipe is known, its success or failure will depend on finding solutions for the challenges while defining, structuring, developing, and implementing AMPM system.

  • 25.
    Parida, Aditya
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Stenström, Christer
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Project: Link and Effect Model for Maintenance of Railway Infrastructure2011Annet (Annet (populærvitenskap, debatt, mm))
  • 26.
    Parida, Aditya
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Stenström, Christer
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Kumar, Uday
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Performance Measurement for Managing Railway Infrastructure2014Inngår i: The international Journal of railway technology, ISSN 2049-5358, E-ISSN 2053-602X, Vol. 2, nr 4, s. 1-14Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    An effective and efficient railway infrastructure is essential to assure assetperformance which is often measured in terms of high availability, high level ofsafety and good track quality, besides value addition. Thus, the measurement ofasset maintenance performance has become an essential element of strategicthinking for railway asset owners and managers. The area of asset maintenanceperformance is relatively new and emerging, besides its complexity with regards to the many internal and external stakeholders, all with conflicting interests. Therailway infrastructures’ overall objectives and strategies are required to be broken down through the hierarchical level, converting them into various key performance indicators (KPIs) for measurement, data collection, analysis, and decision making at appropriate levels through aggregation. This paper looks into some of the performance measurement issues of railways, and how these issues can be solved through data aggregation, analysis, simulation,and presentation. Following a discussion of these issues, a case study is carried out to demonstrate how performance can be analysed and presented.

  • 27.
    Stenström, Christer
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Diffuse Ultrasonic Scattering in Advanced Composites2010Rapport (Annet vitenskapelig)
    Abstract [en]

    Non destructive testing (NDT) is a noninvasive technique used for characterization and inspection of the integrity of objects. NDT is an important tool for research, manufacturing monitoring and in-service inspections. Ultrasonic testing is the most used NDT technique, which for advanced composites can identify several types of defects, like delamination and interlaminar cracks. Diffuse ultrasonics has shown to be able to extract information at the microscale of metals and therefore it is believed it can be used for advanced composites to extract microstructural information, i.e. at the level of fibers. In this thesis, diffuse ultrasonic methods, together with spatial variance analysis, have been used to quantify the scattering within unidirectional advanced composites that have been loaded to different states of fiber damage. Results show that the spread in data is too large to give a clear trend of how the scattering changes with fiber damage. Further research has to be done in order to lower the spread in the results and increase the reproducibility. This can be done with higher precision in the experimental set-ups and new parametric analysis.

  • 28.
    Stenström, Christer
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Effektsamband för underhåll av järnväg: Förstudie2015Rapport (Annet vitenskapelig)
    Abstract [sv]

    Syftet med förstudien är att beskriva hur en formel för effektsamband mellan underhåll och merförsening för järnvägsinfrastruktur kan byggas upp, samt inventera vilka data en sådan formel behöver och vilka av dessa data som finns tillgängliga i Trafikverkets databaser.Ett effektsamband mellan förebyggande underhåll och merförsening har formulerats: När en inspektion utförs är sannolikheten att hitta ett potentiellt fel mellan 0 och 100 %. Det potentiella felet registreras som en inspektionsanmärkning. Risken att ett potentiellt fel inom en viss tid utvecklas till ett funktionsfel är även den mellan 0 och 100 %. Strikt sett är denna tid lika med angiven åtgärdstid, t.ex. veckoanmärkning, men i praktiken längre. Som ett exempel kan man anta 100 inspektioner, med 10 % sannolikhet att hitta potentiellt fel, 75 % risk för funktionsfel om inte åtgärd vidtas inom en snar framtid och 25 % risk för merförsenande funktionsfel. Detta ger 100 • 0,1 • 0,75 • 0,25 = 1,875 avstyrda merförsenande funktionsfel, och därmed 1,875 • medelmerförsening i minskad merförsening.Resultatet visar att avstyrd merförsening per inspektion för olika system inom de studerade 65 bandelarna ligger mellan 0-40 minuter per inspektion. Detta effektsamband beror dock till stor grad på definitionen av inspektion. Effekt-sambandet beror även på typen av inspektion, t.ex. säkerhets- och underhållsinspektioner. Slutligen beror effektsambandet även på kriterierna som används för tilldelning av prioritet avseende inspektionsanmärkningar.En följdfråga till mål 1 i denna studie är vad effekten av förebyggande underhåll blir mätt i kronor. Kostnad-nytta-förhållandet (B/C) blir ≈3,3. Resultaten beror dock på inkluderande/uteslutande av användarkostnader.Trafikverket har ett omfattande system för insamling av data som sträcker sig långt tillbaka i tiden. Tillgänglig data är tillräcklig för att beräkna ovan nämnda effektsamband. Men både data och funktioner i databaserna Bessy och Ofelia behöver studeras vidare för att avgöra kvaliteten och betydelsen avseende effektsambanden beskrivna ovan.

  • 29.
    Stenström, Christer
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Idégenerering för tillståndsövervakning av järnvägar och fordon: En workshop med 635-metoden2017Rapport (Annet vitenskapelig)
    Abstract [sv]

    635-metoden har tillämpats i en workshop för att identifiera möjliga praktiska tillämpningar av dataloggers/sensorer i järnvägsinfrastruktur. Workshopen bestod av elva deltagare och varade i tre timmar. Sammanställning resulterade i ca. 40 frågställningar vid införsel eller utökade av sensorer i järnvägar, samt ca. 80 idéer på tillämpningar/fenomen för sensorer i järnvägar. Många frågor och idéer på tillämpningar är väl kända sedan tidigare, men vissa frågor/idéer är mer sällan uttryckta.

    Frågorna/idéerna i denna rapport kan vara behjälpliga vid arbete eller tankeverksamhet kring tillståndsövervakning av järnvägar och rullande materiel. Frågorna/idéerna behandlar både småkalig tillämpning av sensorer och storskaling tillämpning, dvs. sakernas internet eller internet of things.

    För att gå vidare med frågorna/idéerna kan de väljas ut i en workshop i grupp eller genom individuellt arbete. Att utveckla eller diksutera idéerna vidare är dock utom denna rapports räckhåll.

  • 30.
    Stenström, Christer
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Link and Effect Model – Part II: Methods for Measuring Maintenance Performance of Rail Infrastructure2016Rapport (Annet vitenskapelig)
    Abstract [en]

    Congestion of roads and sky, increasing energy costs and a demand to reduce emissions, have created a need to shift transportation from road and air to rail. Consequently, rail utilisation is increasing, adding stress to the rail infrastructure and time constraints to maintenance. At the same time, the performance and capacity of rail infrastructure are expected to be preserved or even improved. Railway performance and capacity can be enhanced by: expanding infrastructure; introducing better technology; and improving the efficiency and effectiveness of operation and maintenance. Performance measurement has shown to improve the efficiency and effectiveness of organisations, but the development and integration of performance measurements are essential. A key issue in performance measurement is the process of collecting, storing and converting data into information and knowledge, i.e. data analysis and presentation. Organisations use various systems and methods to collect and analyse data, but the analysis of the collected data to extract relevant information is often a challenge. With improved data analysis and performance measurement, rail transportation can meet the requirements of performance and capacity. Specifically, maintenance planning and optimisation of preventive maintenance can be made more effective, which can decrease interruptions of train operation, reduce costs and ensure safety.In this project, methods for measuring maintenance performance of rail infrastructure are developed. The work aims to facilitate decision-making in rail infrastructure maintenance.Keywords: Operation and maintenance, indicators, performance measurement, maintenance cost, rail infrastructure, linear assets, preventive maintenance, corrective maintenance, aggregation, composite indicators, cost-benefit analysis, decision support

  • 31.
    Stenström, Christer
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Link and effect model for performance improvement of railway infrastructure2012Licentiatavhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Railway traffic has increased over the last decade and it is believed to increase further with transportation shifting from road to rail, due to rising energy costs and the demand to reduce emissions. To manage railway infrastructure assets effectively against agreed-upon and set objectives, performance must be measured and monitored. Different systems are used to collect and store data of traffic, failures, inspections, track quality, etc., for subsequent analysis and data exchange. Performance indicators (PIs), e.g. for RAMS (reliability, availability, maintainability, safety), are continuously developed to support infrastructure managers (IMs) in identifying performance killers in order to make efficient and effective decisions. However, they are often ad hoc and seldom standardised. Moreover, the use of standards and the need for harmonisation of railway operations have grown with interoperability, e.g. building of a trans-European railway network. The~efficiency and effectiveness of railway infrastructure can be improved if an appropriate performance measurement (PM) system is identified and specifically developed. In traditional PM systems, PIs are given threshold values, indicating when an action needs to be taken, i.e. they can to some extent be reactive. Also, PIs are often aggregated measures, which can make them abstract. By this trend in transportation and shortcomings in performance measurement, there is a need to improve the strategic planning and measurement of performance for more proactive decision making and future standardisation.In this research, a link and effect model for performance improvement of railway infrastructure is developed. It provides a continuous methodology for breaking down objectives into operational requirements and linking them to results, using performance indicators, and algorithms for data analysis and simulation, for decision support.Keywords: railway infrastructure, performance, RAMS, maintenance, dependability, indicators, link and effect, decision support

  • 32.
    Stenström, Christer
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Maintenance performance measurement of railway infrastructure with focus on the Swedish network2012Rapport (Annet vitenskapelig)
    Abstract [en]

    Railway traffic has increased over the last decade and it is believed to increase further with the movement of transportation from road to rail, due to the increasing energy costs and the demand to reduce emissions. Efficient and effective maintenance is required in order to assure maximum dependability and capacity of the existing railway infrastructure. To manage maintenance successfully within the scope and set objectives, the effect of maintenance activities must be measured and monitored. Performance indicators (PIs) for reliability, capacity, punctuality, etc., are extensively used by infrastructure managers (IMs) in decisions making. However, they are often ad-hoc and seldom standardised. Performance measurements can give large savings and bring business safety by more proactive management, while there are additional costs associated with measuring. It is therefore important to thoroughly analyse what, where, when and how to measure. Thus, there exists a need to study the railway infrastructure PIs used by different IMs, to find out which ones are the most important, which are required and which are not required.In this technical report, a study was undertaken to review the maintenance PIs used by researchers in the field of railway maintenance, as well as reviewing European railway project reports, and also documentations of the Swedish infrastructure manager Trafikverket, like policy documents, handbooks, etc. Interviews were also carried out to get additional inputs. In order to understand the different PIs, a high-level study of the maintenance of railway infrastructure in Sweden was carried out as well.The listed indicators form a basis for constructing a maintenance performance measurement system for railway infrastructure.

  • 33.
    Stenström, Christer
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Mått för tillgänglighet i järnvägen2015Konferansepaper (Annet vitenskapelig)
    Abstract [sv]

    Tillgänglighet är ett mått på driftsäkerhet och mäter förmågan hos en enhet att kunna utföra krävd funktion under angivna förutsättningar vid ett givet tillfälle eller tidsintervall. Mått på tillgänglighet kan hittas i många områden, såsom inom elektronik, IT, militär, elnät och industri. Men ett sådan mått har inte integrerats i järnvägar enligt erkända definitioner. Måttet är intressant eftersom det inbegriper både tekniska och organisatoriska faktorer. Vikten av att kunna mäta tillgänglighet i järnvägar har betonats i olika järnvägsprojekt, t.ex. i EU-projektet INNOTRACK. Därmed, som en del i projektet Åtgärds- och effektmodell, i samarbete med Trafikverket, Järnvägstekniskt centrum och Luleå tekniska universitet, har tillgänglighet som mått inom järnvägar studerats.Resultet visar att det föreslagna tillgänglighetmåttet ger en högre korrelation med tågförseningar (R^2 = 0,94) än vad funktionsfel ger med tågförseningar (R^2 = 0,73). Resultatet är rimligt eftersom tillgängligheten beror på funktionssäkerhet, underhållsmässighet och underhållssäkerhet, d.v.s. det innefattar funktionsfel, reparationstid och logistiktid.

  • 34.
    Stenström, Christer
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Nyckeltal för driftsäkerhet inom järnvägstransport2017Rapport (Annet vitenskapelig)
    Abstract [sv]

    Driftsäkra järnvägar och tåg är avgörande för konkurrenskraftig och ökande andel järnvägstranport. För uppföljning av driftsäkerhet använder infrastrukturförvaltare (Trafikverket), tågoperatörer och entreprenörer olika indikatorer, så som merförsening och antal funktionsfel. Indikatorerna mäter olika aspekter och kan illustreras mer eller mindre intuitivt och tilltalande. Metod för definiering och införsel av indikatorer skiljer sig mellan organisationer. En enkel och vanlig metod är diskussion och beslut inom en sammanträdande grupp. En mer objektiv metod är att följa uppsatta riktlinjer för definiering och utvärdering av indikatorer. Dock är det få allmängiltiga metoder tillgängliga för att definiera indikatorer. Utifrån behov inom järnvägstransport och avsaknaden av metoder för definiering och utvärdering av indikatorer, avses i denna studie en sådan allmänt tillämplig metod presenteras och appliceras inom järnvägstransport. Applicering innebär att i detalj dokumentera två indikatorer som kan användas som branschgemensamma nyckeltal inom järnvägstransport.

    Två indikatorer definierades och utvärderade i denna studie avseende möjlighet att tillämpa dessa som branschgemensamma indikatorer inom järnvägstransport. Val av indikatorer utgick från litteraturstudie av i Sverige gällande standarder avseende driftsäkerhet. Definiering och utvärdering av valda indikatorer utgick från mall av Neely (2002) bestående av 46 frågor.

    De definierade och utvärderade indikatorerna är tillgänglighet och feleffektmatris. Definiering och utvärdering av de två indikatorerna, med utgång från givna 46 frågor, tog i denna rapport fyra arbetsdagar (16 timmar/nyckeltal). Detta ger en fingervisning på arbetsinsatsen som krävs för en organisation som vill införa föreslagen metod för att definiera indikatorer. Förutsatt att data och ett underhållssystem finns tillgängligt, består kostnaderna vid implementering och drift i stora drag av: definiering och utvärdering; implementering av kod i underhållssystem; förbättringsarbete av indikatorer och kod; samt drift av kod i underhållssystem. Det kan därmed vara relevant att utföra en kostnad-nytta-analys avseende indikatorerna. En stor kostnad i sammanhanget är insamling av data. Dock ska denna kostnad eventuellt inte tillskrivas till indikatorerna, eftersom det troligtvis inte är acceptabelt att inte samla in data avseende antal fel, återställelsetider och merförseningar.

    Tre överväganden berörande indikatorn tillgänglighet som bör tas i beaktning är: möjlighet att bryta ner indikatorn för att komma närmare orsakerna till indikatorvärden; tidsrymd för beräkning; samt användande av median, medelvärde och registrerade återställningstider vid beräkning. Valen som görs vid en mjukvaruimplementering kan uppdateras efterhand med erfarenhet från tillämpning.

    En egenskap hos feleffektmatrisen, så som den är tillämpad i denna studie, är att den påverkas av tidtabeller och gångtidstillägg. Tillgänglighet påverkas inte av tidtabeller och gångtidstillägg, men kan istället inte fånga upp skillnaden mellan få långa fel och många korta fel, så som feleffektmatrisen gör. I detta avseende kompletterar tillgänglighet och feleffektmatris varandra.

  • 35.
    Stenström, Christer
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Operation and maintenance performance of rail infrastructure: Model and Methods2014Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Congestion of roads and sky, increasing energy costs and a demand to reduce emissions, have created a need to shift transportation from road and air to rail. Consequently, rail utilisation is increasing, adding stress to the rail infrastructure and time constraints to maintenance. At the same time, the performance and capacity of rail infrastructure are expected to be preserved or even improved. Railway performance and capacity can be enhanced by: expanding infrastructure; introducing better technology; and improving the efficiency and effectiveness of operation and maintenance. Performance measurement has shown to improve the efficiency and effectiveness of organisations, but the development and integration of performance measurements are essential. A key issue in performance measurement is the process of collecting, storing and converting data into information and knowledge, i.e. data analysis and presentation. Organisations use various systems and methods to collect and analyse data, but the analysis of the collected data to extract relevant information is often a challenge. With improved data analysis and performance measurement, rail transportation can meet the requirements of performance and capacity. Specifically, maintenance planning and optimisation of preventive maintenance can be made more effective, which can decrease interruptions of train operation, reduce costs and ensure safety.In this thesis, a model for monitoring and analysis of operation and maintenance performance of rail infrastructure is developed. The model includes various methods for analysis of operation and maintenance data. The work aims to facilitate improvements and optimisation of decision-making in railways.The thesis consists of two parts. The first part gives an introductory summary of the subject and research, followed by a discussion of the appended papers, an extension of the research and conclusions. The second part consists of five appended papers. The first paper concerns the development of a model for improving performance measurement of rail infrastructure. The second paper is a study of indicators related to rail infrastructure performance. The three subsequent papers are development of data analysis methods for: operational availability of rail infrastructure, composite indicators and maintenance costs.Keywords: operation and maintenance, indicators, performance measurement, maintenance cost, rail infrastructure, linear assets, preventive maintenance, corrective maintenance, aggregation, composite indicators, cost-benefit analysis, decision support

  • 36.
    Stenström, Christer
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Performance measurement of railway infrastructure2013Konferansepaper (Annet vitenskapelig)
  • 37.
    Stenström, Christer
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Ultrasonics for Monitoring of Mining Mill Linings: Pilot Experiments2016Rapport (Annet vitenskapelig)
    Abstract [en]

    Mining mill linings are continuously exposed to wear induced by the charge, and thus, mill operation has to be interrupted on a regular basis for inspections. Stoppages due to inspections and replacement of linings lead to large production and monetary losses; especially in case of unplanned corrective maintenance. Condition monitoring during mill operation can assist in the maintenance planning and decision process to increase the availability and the overall performance of the material processing.In this pilot study, the feasibility of using waterflow ultrasonics for condition monitoring of the lining of mining mills during operation is to be investigated. The proposed waterflow ultrasonic technique uses a water beam to transmit the ultrasound to the mill shell and lining. By measuring the time of flight (TOF), it can be possible to monitor the thickness of mill linings, without the need of interrupting operation. The method can lead to significant energy and monetary savings by reducing inspections and corrective maintenance stoppages, and possibly increase product quality by optimised performance.Since steel has a very high acoustic impedance in comparison to rubber, TOF measurements on aluminium-rubber has been used as an intermediate step towards the goal of measuring steel-rubber combinations. TOF measurements of aluminium-rubber layers have been achieved, and advancement towards the understanding of TOF measurements in steel-rubber laysers have been achieved.The following conclusions have been reached:- Rubber thickness can be measured through aluminium. In practice, aluminium plugs/rivets can be mounted on the steel shell of a mill to measure TOF of rubber shell plates and lifter bars.- Ultrasound signals can be measured through steel-rubber layers in through-transmission and pitch-catch set-ups.- Ultrasound signals measured in pulse-echo or pitch-catch set-up on a solid steel plate connected to rubber, give rise to reverberations (ringing signal) that mask the rubber backwall echoes. For avoiding reverberations of steel plate sides, an experimental set-up requires the steel plate to be at least eight times wider and deeper (x- and y-axis) than the thickness (z-axis) of the rubber under inspection.Keywords: ultrasonic testing, mining mill lining, lined pipes, NDT, condition monitoring, comminution, non-destructive testing, thickness gauge.

  • 38.
    Stenström, Christer
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Al-Jumaili, Mustafa
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Parida, Aditya
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Computerised Analysis of Text Entry Fields in Maintenance Work Orders Data2014Inngår i: Proceedings of the 3rd international workshop and congress on eMaintenance: June 17-18 Luleå, Sweden : eMaintenance, Trends in technologies & methodologies, challenges, possibilites and applications / [ed] Uday Kumar; Ramin Karim; Aditya Parida; Phillip Tretten, Luleå: Luleå tekniska universitet, 2014, s. 97-100Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Enterprise resource planning systems and computerised maintenance management systems are commonly used by organisations for handling of maintenance work orders through a graphical user interface. A work order consists of a number of data fields, such as drop-down lists, list boxes, check boxes and text entry fields. In contrast to the other data fields, the operator has the freedom to type in any text in the text entry fields, to complement and make the work order description complete. Accordingly, the text entry fields of work orders can contain any words, in any number, as necessary.Data quality is crucial in statistical analysis of work orders data, and therefore manual analysis of work orders’ text entry fields is often necessary before any decision making. However, this may be a very tedious and resource consuming process.In this article, we apply computerised analysis of text entry fields of work orders data, to study if it can bring further value in the assessment of technical assets’ performance.Keywords:Data quality, eMaintenance, maintenance, work orders, failure, decision support, natural language processing

  • 39.
    Stenström, Christer
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Al-Jumaili, Mustafa
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Parida, Aditya
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Natural language processing of maintenance records data2015Inngår i: International Journal of COMADEM, ISSN 1363-7681, Vol. 18, nr 2, s. 33-37Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Enterprise resource planning systems and maintenance management systems are commonly used by organisations for handling of maintenance records, through a graphical user interface. A maintenance record consists of a number of data fields, such as drop-down lists, list boxes, check boxes and text entry fields. In contrast to the other data fields, the operator has the freedom to type in any text in the text entry fields, to complement and make the maintenance record as complete as possible. Accordingly, the text entry fields of maintenance records can contain any words, in any number.Data quality is crucial in statistical analysis of maintenance records, and therefore manual analysis of maintenance records’ text entry fields is often necessary before any decision making. However, this may be a very tedious and resource consuming process.In this article, natural language processing is applied to text entry fields of maintenance records in a case study, to show how it can bring further value in the assessment of technical assets’ performance.Keywords: Maintenance records, Natural language processing, Structured and unstructured data, Data quality, Rail infrastructure.

  • 40.
    Stenström, Christer
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Carlson, Johan E.
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Signaler och system.
    Lundberg, Jan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Mining mill condition monitoring using water jet ultrasonics2013Inngår i: 2012 IEEE International Ultrasonics Symposium (IUS), Piscataway, NJ: IEEE Communications Society, 2013, s. 1913-1916Konferansepaper (Fagfellevurdert)
    Abstract [en]

    In this paper we investigate the feasibility of using a water jet ultrasound scanning system for condition monitoring of the shell of a rotating mining mill. The practical requirements of such a system were first analyzed, which shows that it is possible to achieve the spatial resolution of 1±1 mm, using a pulse-echo setup with a pulse repetition frequency of approximately 6 kHz. Experiments were then performed on a lab-scale prototype, where typical defects were introduced. The results show that it is possible to detect and image internal defects down to a size of around than 1 ± 0.4 mm.

  • 41.
    Stenström, Christer
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Carlson, Johan
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Signaler och system.
    Lundberg, Jan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Condition monitoring of cracks and wear in mining mills using water squirter ultrasonics2015Inngår i: International Journal of Condition Monitoring, ISSN 0019-6398, E-ISSN 2047-6426, Vol. 5, nr 1, s. 2-8Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Mining mills are continuously exposed to loads that give rise to wear of the liners, as well as fatigue and crack development in the steel shell. The feasibility of using water squirter ultrasonics for condition monitoring of the shell and the lining of mining mills during operation has been studied in this paper. This method will make it possible to monitor cracks in mining mills without stopping them, which can result in significant monetary savings due to less downtime and increased product quality. The practical requirements of such a system were first analysed, which shows that it is possible to achieve the spatial resolution of 1 × 1 mm, using a pulse-echo set-up with a pulse repetition frequency of approximately 6 kHz. Experiments were then performed on a lab-scale prototype, where typical defects were introduced. The results show that it is possible to detect and image internal defects down to a size of around 1 × 0.4 mm.

  • 42.
    Stenström, Christer
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Eriksson, Kjell
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Material- och solidmekanik.
    The J-contour integral in peridynamics via displacements2019Inngår i: International Journal of Fracture, ISSN 0376-9429, E-ISSN 1573-2673, Vol. 216, nr 2, s. 173-183Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Peridynamics is a nonlocal formulation of solid mechanics capable of unguided modelling of crack initiation, propagation and fracture. Peridynamics is based upon integral equations, thereby avoiding spatial derivatives, which are not defined at discontinuities, such as crack surfaces. Rice’s J-contour integral is a firmly established expression in classic continuum solid mechanics, used as a fracture characterizing parameter for both linear and nonlinear elastic materials. A corresponding nonlocal J-integral has previously been derived for peridynamic modelling, which is based on the calculation of a set of displacement derivatives and force interactions associated with the contour of the integral. In this paper, we present an alternative calculation of the classical linear elastic J-integral for use in peridynamics, by writing Rice’s J-integral as a function entirely of displacement derivatives. The accuracy of the proposed J-integral on displacement formulation is investigated by applying it to the exact analytical displacement solution of an infinite specimen with a central crack and comparing the exact analytical expression of its J-integral. Further comparison with a well-known peridynamic crack problem shows very good agreement. The suggested method is computationally efficient and further allows testing of the accuracy of a peridynamic model as such.

  • 43.
    Stenström, Christer
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Famurewa, Stephen Mayowa
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Parida, Aditya
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Galar, Diego
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Impact of cold climate on failures in railway infrastructure2012Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Railway traffic has increased over the last decade due to greater energy costs and the need to reduce emissions. Ensuring the dependability and capacity of railway infrastructure requires efficient and effective maintenance which, in turn, requires good understanding of various physical behaviours, e.g. deterioration and environmental effects. This paper studies the effect of cold climate on railway infrastructure performance using statistics and historical work order data. It finds differences in the number of work orders as a function of season and geographical location.Keywords: railway, performance, temperature, winter, cold, climate, failures, infrastructure, snow, ice, maintenance, reliability, dependability

  • 44.
    Stenström, Christer
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Galar, Diego
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Auditoria de Manutenção Baseada em Elementos Quantitativos e Qualitativos em Sistemas de Saúde2011Inngår i: Tecno Hospital, ISSN 1645-9431, nr 47, s. 24-29Artikkel i tidsskrift (Annet vitenskapelig)
    Abstract [en]

    The dependability of hospital facilities and equipments is a critical element in the performance of health care systems. The availability needs to be near one hundred percent, especially equipment related to the emergency department. Faults in equipments have to be rectified as fast as possible, i.e. the organizational readiness and the maintainability of the equipments need to be excellent. This paper introduces a maintenance audit model, based on quantitative and qualitative elements, together with a maturity model for facilities and equipments of health care systems. Qualitative and quantitative methods are combined in order to complement advantages and disadvantages of them both.

  • 45.
    Stenström, Christer
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Juntti, Ulla
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Parida, Aditya
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Kumar, Uday
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Track Maintenance Between Trains Simulation2016Inngår i: Current Trends in Reliability, Availability, Maintainability and Safety: An Industry Perspective / [ed] Uday Kumar; Alireza Ahmadi; Ajit Kumar Verma; Prabhakar Varde, Encyclopedia of Global Archaeology/Springer Verlag, 2016, s. 373-380Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Infrastructure managers (IMs) need to plan their maintenance work about 1½–2 years before a new train time table (TTT) comes into force to minimise the effect on traffic. Maintenance work that is planned in less than 1 year ahead of the TTT has to compete with, or need to be fitted into, operators’ applications for capacity. However, maintenance work is at times planned only a few weeks before execution, and depending on the railway line in question, a few hours during night can be available for maintenance. In addition, sudden failures in track normally require repair immediately or within a day. If rail transportation increases, it also becomes harder to find time in track for maintenance. Therefore, it is of interest to simulate maintenance tasks between trains to minimise track maintenance possession time. Such simulation can be used to: study maintenance work in TTTs with random and regular train departures; study the effect of exceeding allocated maintenance windows; and to study the effect of increase in train frequency. In this paper, Monte Carlo method is applied to simulate track maintenance between trains as a function of train frequency.

  • 46.
    Stenström, Christer
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Lindqvist, Jonas
    Trafikverket.
    Andersson, Fredrik
    Sweco.
    Tillståndsövervakning baserat på billiga sensorer och öppen elektronik: För snabbare utveckling av IoT inom järnväg2018Rapport (Annet vitenskapelig)
    Abstract [sv]

    Denna rapport innehåller resultatet från projektet Tillståndsbaserat underhåll av järnvägsinfrastrukturbaserat på sakernas internet-lösningar, med stöd från det strategiskainnovationsprogrammet InfraSweden2030, en gemensam satsning av VINNOVA, Formasoch Energimyndigheten.Syftet med projektet är att utveckla och fälttesta mätsystem för tillståndsbedömningoch underhåll av järnvägsinfrastruktur. Mätsystemen bygger på öppen hård- och mjukvara.Projektgruppen består av Damill, eMaintenance365, Infranord, Järnvägstekniskt centrum(JVTC), ämnet drift- och underhållsteknik på Luleå tekniska universitet (LTU), SwecoRail, Trafikverket och Vossloh. Projektet har pågått mellan okt 2016 – nov 2018.

  • 47.
    Stenström, Christer
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Lundberg, Jan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Carlson, Johan
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Signaler och system.
    Project: Squirter Ultrasonic Thickness Gauge for Monitoring of Mining Mill Lining During Operation (SV: Mätning av tjocklek på kvarninfodring med ultraljud under drift)2014Annet (Annet (populærvitenskap, debatt, mm))
  • 48.
    Stenström, Christer
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Norrbin, Per
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Parida, Aditya
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Kumar, Uday
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Preventive and corrective maintenance: cost comparison and cost–benefit analysis2016Inngår i: Structure and Infrastructure Engineering, ISSN 1573-2479, E-ISSN 1744-8980, Vol. 12, nr 5, s. 603-617Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    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.

  • 49.
    Stenström, Christer
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Parida, Aditya
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Link and Effect Model for Maintenance of Railway Infrastructure2013Rapport (Annet vitenskapelig)
    Abstract [en]

    Railways are large linear assets of electrical and mechanical systems, and consequently the infrastructure managers (IMs) are extensive with many stakeholder involved. The railway infrastructure and the IMs consist of technical and organisational levels: system, subsystem and component levels, and strategic, tactical and operational levels, respectively. The purpose of this project is to develop a methodology for improving performance measurement systems for railway infrastructure, which integrates both the technical and organisational perspectives, vertically and laterally. It involves several objectives, hundreds of parameters and indicators, data collection, and aggregation of information.The work that has been carried out is as under:• Overall mapping of the operation and maintenance of the Swedish railway infrastructure through interviews and literature review. (Section 4.1)• Railway infrastructure performance indicators have been mapped, structured and compared to European Standards, to act as a reference. About 120 measures were identified and 11 are similar to European Standards maintenance key performance indicators. (Section 4.2 and Appendix A)• A link and effect model has been developed to facilitate improvement of performance measurement systems, by combining performance measurement and engineering principles. It is based on the plan-do-study-act (PDSA) cycle with emphasis on the key components of strategic planning. A case study on the Swedish Iron Ore Line has been carried out to verify the model. (Section 4.3)• An index, or composite indicator, for operation and maintenance of railway infrastructure was developed within the case study, similar to risk matrices and failure mode effect analysis (FMEA). The index is based on infrastructure failures and train delays with equal weighting. (Section 4.3)• Another index has been developed in a continuation of the case study that also includes maintenance times and further weighting. (Section 4.4)• The impact and significance of cold climate on failures in railway infrastructure has been studied in another case study on the Iron Ore Line and the Coast-to-Coast Line in Sweden. (Section 4.5)• A railway RAMS (reliability, availability, maintainability and safety/supportability) analyser software has been developed to demonstrate cost-effective analysis, data presentation and simulation. (Section 4.6 and Appendix B)• As a prestudy, maintenance possession time (maintainability) has been simulated in terms of the actual time to repair as a function of track capacity utilisation, set-up/clearance time and required active repair time. (Section 4.7)Keywords: Railways, train delays, Swedish Iron Ore Line, operation and maintenance, dependability, RAMS, reliability, availability, maintainability, supportability, safety

  • 50.
    Stenström, Christer
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Parida, Aditya
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Measuring performance of linear assets considering their spatial extension2014Inngår i: Journal of Quality in Maintenance Engineering, ISSN 1355-2511, E-ISSN 1758-7832, Vol. 20, nr 3, s. 276-289Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Purpose - In this study we investigate how performance of linear assets can be analysed and displayed, considering both the technical asset and the user context, to simplify cognitive tasks of planning and decision-making.Design/methodology/approach - Linear, or continuous assets, such as roads, railways, electrical grids and pipelines, are large, geographically spread out technical systems. Linear assets are comprised of system, subsystem and component levels. Thus, asset managers are involved with each level of the linear asset; asset management has strategic, tactical and operational levels. A methodology is developed to link together the technical and organisational levels and to measure asset performance considering their spatial extension. Geographical location and time are used as independent variables.Findings - For performance measurement of linear assets, it is found that the spatial extension is an equally generic dimension as time is for technical assets in general. Furthermore, as linear assets actually are combinations of linear and point assets; separate analysis of these assets is a prerequisite. Asset performance has been studied in a case study in terms failures and cost; the results indicate that the methodology visualise poor, as well as good, performance in an easy to interpret manner. Besides, the results indicate that other parameters related to dependability can be presented in a similar way.Practical implications - This study highlights the importance of including the spatial or geographical extension of linear assets in infrastructure managers’ performance measurement. It is believed that the methodology can make planning and decision making more effective by pointing out improvement areas in technical assets, in a way that is appealing to both technicians and managers.Originality/value - The presented methodology and case study analysed performance in function of both the technical and organisational levels, including the spatial component. It is believed that the methodology for analysing and visualising performance of linear assets is distinctive.Keywords - Linear assets, performance measurement, dependability, maintenance, eMaintenance, railways

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