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  • 1. Ahmadi, Alireza
    et al.
    Kumar, Uday
    Ghodrati, Behzad
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Risk based maintenance decision for periodically tested repairable components subject to hidden failure2011Inngår i: Proceedings of 2nd International Conference on Reliability, Safety and Hazard - ICRESH 2010: Mumbai Dec 15-16, 2010 / [ed] P V Varde, Piscataway, NJ: IEEE Communications Society , 2011, s. 197-204Konferansepaper (Fagfellevurdert)
    Abstract [en]

    This paper aims to develop a graphical method to facilitate the identification of risk and cost of postponement of restoration for repairable components which are periodically tested and whose failures are hidden, i.e, are detectable by inspection or upon demand. The paper focuses on the items which are under aging, however, the methodology is flexible to implement for any aging pattern.

    The paper considers Failure Finding Inspection (FFI) with restoration actions (FFI+Res), for the “safety effect” categories of hidden failures. As-bad-as-old (ABAO) inspection effectiveness and as-good-as-new (AGAN) restoration effectiveness are considered. In case of repair due to findings by inspection, as-bad-as-old repair effectiveness is considered.

    The graphical methodology proposed in this paper considers inspection and repair times, as well as the costs associated with accident, inspection, repair, and restoration, and takes into account the opportunity losses due to the maintenance downtime.

    The analytical approach is based on the Mean Fractional Dead Time. In the case of an operational limit, when it is not possible to remove the unit for restoration, or one needs to use the unit longer than the expected operating time, the paper introduces an approach to analyzing the possibility of and conditions for providing an extension to the restoration interval that satisfies the risk constraints and the business requirements at the same time.

  • 2.
    Aminu Sanda, Mohammed
    et al.
    Luleå tekniska universitet, Institutionen för ekonomi, teknik och samhälle.
    Abrahamsson, Lena
    Luleå tekniska universitet, Arbetsvetenskap.
    Galar, Diego
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Kumar, Uday
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Sandin, Fredrik
    Luleå tekniska universitet, EISLAB.
    Delsing, Jerker
    Luleå tekniska universitet, EISLAB.
    Lean instrumentation framework for sensor pruning and optimization in condition monitoring2011Inngår i: The Eighth International Conference on Condition Monitoring and Machinery Failure Prevention Technologies: St. David's Hotel, Cardiff, Wales, 20 - 22 June 2011 ; CM2011/MFPT2011, Longborough, Glos: Coxmoor Publishing Co. , 2011, s. 202-215Konferansepaper (Fagfellevurdert)
    Abstract [en]

    This paper discusses a lean instrumentation framework for guiding the introduction of the lean concept in condition monitoring in order to enhance the organizational capability (i.e. human, technical and management trichotomy) and reduce the complexity in the maintenance management systems of industrial companies. Additionally, decision-making, based on severity diagnosis and prognosis in condition monitoring, is a complex maintenance function which is based on large data-set of sensors measurements.

    Yet, the entirety of such decision-making is not dependent on only the sensors measurements, but also on other important indices, such as the human factors, organizational aspects and knowledge management. This is because, the ability to identify significant features from large amount of measured data is a major challenge for automated defect diagnosis, a situation that necessitate the need to identify signal transformations and features in new domains.

    The need for the lean instrumentation framework is justified by the desire to have a modern condition monitoring system with the capability of pruning to the optimal level the number of sensors required for efficient and effective serviceability of the maintenance process. It is concluded that there are methodologies that can be developed to enable more efficient condition monitoring systems, with benefits for many processes along the value chain.

    Fulltekst (pdf)
    FULLTEXT01
  • 3.
    Arasteh khouy, Iman
    et al.
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Larsson-Kråik, Per-Olof
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Nissen, Arne
    Trafikverket.
    Kumar, Uday
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Cost-effective track geometry maintenance limits2016Inngår i: Proceedings of the Institution of mechanical engineers. Part F, journal of rail and rapid transit, ISSN 0954-4097, E-ISSN 2041-3017, Vol. 230, nr 2, s. 611-622Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In the past, railway maintenance actions were usually planned based on the knowledge and experience of the infrastructure owner. The main goal was to provide a high level of safety, and there was little concern about economic and operational optimisation issues. Today, however, a deregulated competitive environment and budget limitations are forcing railway infrastructures to move from safety limits to cost-effective maintenance limits to optimise operation and maintenance procedures. By so doing, one widens the discussion to include both operational safety and cost-effectiveness for the whole railway transport system. In this study, a cost model is proposed to specify the cost-effective maintenance limits for track geometry maintenance. The proposed model considers the degradation rates of different track sections and takes into account the costs associated with inspection, tamping, delay time penalties, and risk of accidents due to poor track quality. It draws on track geometry data from the Iron Ore Line (Malmbanan) in northern Sweden, used by both passenger and freight trains, to estimate the geometrical degradation rate of each section. The methodology is based on reliability and cost analysis and facilitates the maintenance decision-making process to identify cost-effective maintenance thresholds.

  • 4.
    Arasteh khouy, Iman
    et al.
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Larsson-Kråik, Per-Olof
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Nissen, Arne
    Trafikverket.
    Lundberg, Jan
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Kumar, Uday
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Geometrical degradation of railway turnouts: a case study from a Swedish heavy haul railroad2014Inngår i: Proceedings of the Institution of mechanical engineers. Part F, journal of rail and rapid transit, ISSN 0954-4097, E-ISSN 2041-3017, Vol. 228, nr 6, s. 611-619Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Turnouts are critical components of track systems in terms of safety, operation and maintenance. Each year, a considerable part of the maintenance budget is spent on their inspection, maintenance and renewal. Applying a cost-effective maintenance strategy helps to achieve the best performance at the lowest possible cost. In Sweden, the geometry of turnouts is inspected at predefined time intervals using the STRIX / IMV 100 track measurement car. This study uses time series for the measured longitudinal level of turnouts on the Iron Ore Line (Malmbanan) in northern Sweden. Two different approaches are applied to analyse the geometrical degradation of turnouts due to dynamic forces generated by train traffic. In the first approach, the recorded measurements are adjusted at the crossing point and then the relative geometrical degradation of turnouts is evaluated by using two defined parameters, the absolute residual area and the maximum settlement, In the second approach, various geometry parameters are defined to estimate the degradation in each measurement separately. The growth rate of the longitudinal level degradation as a function of million gross tonnes / time is evaluated. The proposed methods are based on characterisation of the individual track measurements. The results facilitate correct decision-making in the maintenance process through understanding the degradation rate and defining the optimal maintenance thresholds for the planning process. In the long run, this can lead to a cost-effective maintenance strategy with optimised inspection and maintenance intervals.

  • 5.
    Candell, Olov
    et al.
    Saab Aerotech, Aircraft Services Division, Linköping, SE-581 88, Sweden.
    Karim, Ramin
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Söderholm, Peter
    Luleå tekniska universitet, Industriell Ekonomi.
    Kumar, Uday
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Server-oriented information logistics as support to intelligent transport services2010Inngår i: 16th World Congress and Exhibition on Intelligent Transport Systems 2009: 16th ITS World Congress ; Stockholm, Sweden, 21 - 25 September 2009, Curran Associates, Inc. , 2010Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Today‟s society is dependent on an increasing volume of transportation services, which contributes to escalating requirements on economy, dependability, safety, and sustainability of applied transportation systems. When dealing with complex transportation systems with long life cycles, maintenance is fundamental to ensure these critical requirements. The increasing requirements and the technological development have also lead to the emerging approach of eMaintenance, which applies innovative Information & Communication Technology (ICT) to achieve effective information logistics for maintenance purposes. This paper describes the role and development of service-oriented eMaintenance solutions to enable intelligent transportation services and some related research efforts within railway and aviation.

    Fulltekst (pdf)
    FULLTEXT01
  • 6.
    Eker, O.F.
    et al.
    Meliksah University, Kayseri, Turkey.
    Camci, F.
    Meliksah University, Kayseri, Turkey; Integrated Vehicle Health Management Centre, Cranfield University, United Kingdom.
    Kumar, Uday
    Luleå tekniska universitet, Drift, underhåll och akustik.
    SVM based diagnostics on railway turnouts2012Inngår i: International Journal of Performability Engineering, ISSN 0973-1318, Vol. 8, nr 3, s. 289-298Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Railway turnout systems are one of the most critical pieces of equipment in railway infrastructure. Early identification of failures in turnout systems is important to obtain increased availability and safety, and reduced operating and support costs. This paper aims to develop a method to identify 'drive-rod out-of-adjustment' failure mode, one of the most frequently observed failure modes. Support Vector Machine (SVM) with Gaussian kernel is used for diagnosis. In addition, the results of feature selection with statistical t-test and feature reduction with principal component analysis (PCA) are compared in the paper

  • 7.
    Eker, Omer Faruk
    et al.
    Fatih University.
    Camci, Fatih
    Meliksah University, Kayseri.
    Kumar, Uday
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Failure diagnostics on railway turnout systems using support vector machines2010Inngår i: Proceedings of the 1st international workshop and congress on eMaintenance, Luleå tekniska universitet , 2010, s. 248-251Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Railway turnout systems are one of the most critical pieces of equipment in railway infrastructure. Early identification of failures in turnout systems is important to obtain increased availability and safety, and reduced operating & support cost. This paper aims to develop a method to identify „drive-rod out-ofadjustment‟ failure mode, one of the most frequently observed failure modes. Support Vector Machine with Gaussian kernel is used for classification. In addition, results of feature selection with statistical t-test and feature reduction with principal component analysis are compared in the paper.

    Fulltekst (pdf)
    FULLTEXT01
  • 8.
    Famurewa, Stephen Mayowa
    et al.
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Asplund, Matthias
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Rantatalo, Matti
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Kumar, Uday
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Maintenance improvement: an opportunity for railway infrastructure capacity enhancement2013Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The continually increasing demand on railway service in terms of the quantity and quality of both passenger and freight train operations is the core of the general railway capacity challenge. Moreover, this challenge has been the driver for some improvements in the technical system, traffic operation & management as well as maintenance process, although the room for improvement in the maintenance function is still large. An effective capacity management entails critical study of the three essential capacity parameters: infrastructure, traffic and operating parameters.

    To further explore the fundamentals of capacity management, this paper investigates some essential issues on railway infrastructure capacity. A review of the general railway infrastructure capacity challenge and management is presented, including some strategic measures to enhance capacity and quality of service of existing infrastructure. We have proposed maintenance improvement framework to explore the opportunity of improving the capacity situation on a network. This framework will facilitate the identification of both critical systems and activities with the largest impact on the capacity and also some root causes for critical system. The framework has suggested methodology to improve allocation and utilisation of track possession time, giving room for capacity expansion of existing railway infrastructure.

    Fulltekst (pdf)
    FULLTEXT01
  • 9.
    Famurewa, Stephen Mayowa
    et al.
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Asplund, Matthias
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Rantatalo, Matti
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Parida, Aditya
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Kumar, Uday
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Maintenance analysis for continuous improvement of railway infrastructure performance2015Inngår i: Structure and Infrastructure Engineering, ISSN 1573-2479, E-ISSN 1744-8980, Vol. 11, nr 7, s. 957-969Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Railway transport system is massive and complex, and as such it requires effective maintenance to achieve the business goal of safe, economic and sustainable transportation of passengers and goods. The growing demand for improved service quality and capacity target by railway infrastructure managers requires appropriate maintenance analysis to facilitate continuous improvement of infrastructure performance. This paper presents the application of risk matrix as a maintenance analysis method for the identification of track zones that are bottlenecks that limit operational capacity and quality. Furthermore, an adapted analysis method is proposed to create a hierarchical improvement list for addressing the problem of train mission interruption and reduced operational capacity. A case study of a line section of the Swedish network is presented. The result classifies the zones on the line section into different risk categories based on their contribution to loss of capacity and punctuality. In addition, an improvement list for the lower-level system is presented to facilitate maintenance decisions and continuous improvement at both operational and strategic levels.

  • 10.
    Famurewa, Stephen Mayowa
    et al.
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Juntti, Ulla
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Kumar, Uday
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Performance based railway infrastructure maintenance: Towards achieving maintenance objectives2011Inngår i: MPMM 2011: Maintenance Performance Measurement & Management: Conference Proceedings / [ed] Diego Galar; Aditya Parida; Håkan Schunnesson; Uday Kumar, Luleå: Luleå tekniska universitet , 2011, s. 233-240Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The measurement and management of railway infrastructure capacity has received increased attention in recent years due to the pressing need to optimally utilized the existing railway infrastructure capacity and as well create more capacity. In a bid to improve the maintenance function and utilization of the existing infrastructure, some of the infrastructure managers (IM) reviewed their approach to outsourcing of maintenance functions, giving larger responsibilities to maintenance agent called contractors. The growing responsibilities of the contractors are however resisted by some IM due to some unresolved doubts. This paper discusses the outcome oriented approach to maintenance outsourcing; performance based railway infrastructure maintenance contracting with its issues and challenges. A framework is described and performance monitoring tool is proposed to enhance Performance Based Railway Infrastructure Maintenance (PBRIM) contracting as a strategy for improving the effectiveness of maintenance function

    Fulltekst (pdf)
    FULLTEXT01
  • 11.
    Famurewa, Stephen Mayowa
    et al.
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Juntti, Ulla
    Luleå Railway Research Centre.
    Nissen, Arne
    Trafikverket.
    Kumar, Uday
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Augmented utilisation of possession time: Analysis for track geometry maintenance2016Inngår i: Proceedings of the Institution of mechanical engineers. Part F, journal of rail and rapid transit, ISSN 0954-4097, E-ISSN 2041-3017, Vol. 230, nr 4, s. 1118-1130Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The demand for increased capacity on existing railway networks is a challenge for many Europe-based infrastructure managers; addressing this challenge requires augmented utilisation of track possession time. It is considered that large-scale maintenance tasks such as geometry maintenance can be improved; thus, reducing the on-track maintenance time and allowing more traffic. In this study, an analysis of track geometry maintenance was performed with the objective of reducing the required possession time. The procedure and models for planning and optimizing track geometry maintenance are presented. A statistical model that uses a simulation approach was used to determine the condition of the track geometry, and a schedule optimization problem was formulated to support intervention decisions and optimize the track possession time. The results of the case study show that optimizing the maintenance shift length and cycle length are opportunities to reduce the extent of track possession required for the maintenance of the track geometry. In addition, continuous improvement of the tamping process through lean analysis promises about a 45% reduction in the required possession time for a tamping cycle.

  • 12.
    Famurewa, Stephen Mayowa
    et al.
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Parida, Aditya
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Kumar, Uday
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Application of Maintenance Performance Measurement for Continuous Improvement in Railway Infrastructure Management2015Inngår i: International Journal of COMADEM, ISSN 1363-7681, Vol. 18, nr 1, s. 49-58Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Railway transport infrastructure is a linearly distributed asset that requires an effective performance management system to meet sectional and overall business objectives. In particular, an effective performance measurement system with relevant analysis technique in an ongoing manner is necessary to facilitate continuous improvement. Maintenance performance measurement (MPM) is essential to quantify the impact of past maintenance decisions and actions and also to support new decisions. This article presents the challenges of implementing and using MPM systems for maintenance decisions in the railway industry. Thereafter, a risk matrix with maintenance performance indicators is introduced as a complementary analysis tool to identify weak links on a railway line. A case study of a section on the heavy haul line of the Swedish Transport Administration railway network is presented to demonstrate the application of the risk matrix tool for continuous improvement. The results identified the bottlenecks on the line section, which are improvement opportunities for maintenance performance in terms of service quality and capacity target of the infrastructure manager

  • 13.
    Famurewa, Stephen Mayowa
    et al.
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Rantatalo, Matti
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Kumar, Uday
    Luleå tekniska universitet, Drift, underhåll och akustik.
    RAM Modelling of Railway Operational Sections: A Case Study from the Iron Ore Line2014Inngår i: Proceedings of the Second International Conference on Railway Technology: research, development and maintenance ; 8 - 11 April 2014, Ajaccio, Corsica, France / [ed] J. Pombo, Kippen: Civil-Comp Press , 2014, artikkel-id 305Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Railway infrastructure is a linearly distributed asset which has different hierarchical levels such as lines, operational sections, assemblies, modules and maintainable components. The management and performance evaluation of the entire system is done at suitable hierarchical level for efficiency and practicality. It is ideal to assess the integrity as well as the reliability, availability and maintainability (RAM) of the infrastructure on the level of operational sections which are established technical divisions used for traffic operational management by infrastructure administrations. There are several approaches that are used to evaluate the RAM characteristics of a system. This paper presents an approach for RAM simulation of railway operational sections using an event based simulation tool with the Monte Carlo technique. Theinput data used in the RAM modelling includes: historical maintenance and failure data between 2010 and 2012, planned train mission and possible preventive maintenance plans. The outcome of the simulation is the estimation of different RAM parameters over a period of one year. Amongst the parameters are: the expected number of failures and the downtime per operational section, states of each operational section and the overall dependability measure of the line in terms of the success of the planned traffic. These parameters are integrity measures of the asset which can be used for traffic simulation for effective management of traffic. They are also useful for logistic support planning that is required for cost effective and highly dependable infrastructure management.

  • 14.
    Famurewa, Stephen Mayowa
    et al.
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Stenström, Christer
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Asplund, Matthias
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Galar, Diego
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Kumar, Uday
    Luleå tekniska universitet, 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.

  • 15.
    Famurewa, Stephen Mayowa
    et al.
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Xin, Tao
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Rantatalo, Matti
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Kumar, Uday
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Optimisation of maintenance track possession time: A tamping case study2015Inngår i: Proceedings of the Institution of mechanical engineers. Part F, journal of rail and rapid transit, ISSN 0954-4097, E-ISSN 2041-3017, Vol. 229, nr 1, s. 42726-Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Optimum allocation and efficient utilisation of track possession time are becoming important topics in railway infrastructure management due to increasing capacity demands. This development and other requirements of modern infrastructure management necessitate the improvement of planning and scheduling of large-scale maintenance activities such as tamping. It is therefore necessary to develop short-, medium- and long-term plans for performing tamping on a network or track section within a definite time horizon. To this end, two key aspects of infrastructure maintenance planning are considered in this paper, deterioration modelling and scheduling optimisation. An exponential deterioration function is applied to model the geometry quality of a series of 200 m segments of a 130 km line section, and an empirical model for recovery after tamping intervention is developed. These two models are subsequently used to generate a methodology to optimise a schedule for tamping intervention by minimising the total cost of intervention including the cost of track possession while geometry quality is ascertained to be within a desirable limit. The modelling considers two types of tamping interventions, preventive and corrective, with different intervention limits and tamping machines. The result of this paper suggests a tamping plan which will lead to optimum allocation of track possession time while maintaining the track geometry quality within specified limits.

  • 16.
    Fuqing, Yuan
    et al.
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Kumar, Uday
    Luleå tekniska universitet, Drift, underhåll och akustik.
    A cost model for repairable system considering multi-failure type over finite time horizon2011Inngår i: International Journal of Performability Engineering, ISSN 0973-1318, Vol. 7, nr 2, s. 186-194Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In general, downtime of a system can be attributed due to multiple failure categories and repair costs for each failure categories can be different. Many of these failure types are repaired to a state which can be called as bad as old and such repair actions are termed as “minimal repair”. Many system or components are replaced after a certain number of such minimal repair actions. In this study, we intend to prove that if the system failure process can be described by NHPP (Non Homogenous Poisson Process), then each failure category can also be modelled by NHPP.

    Based on this, a cost model is developed by using the decomposition of the NHPP and renewal theory. Using the cost model, a model is developed to obtain the optimal number of minimum repair action every failure category. Since it is not possible to find any analytical solution, solution to the renewal function, an approximate approach is introduced to obtain numerical solution. Finally, a numerical example is presented to demonstrate the method.

    Fulltekst (pdf)
    FULLTEXT01
  • 17.
    Fuqing, Yuan
    et al.
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Kumar, Uday
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Kernelized proportional intensity model for repairable systems considering piecewise operating conditions2012Inngår i: IEEE Transactions on Reliability, ISSN 0018-9529, E-ISSN 1558-1721, Vol. 61, nr 3, s. 618-624Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The proportional intensity model (PIM) has been used to model the intensity function of repairable systems taking non-time factors, such as operating conditions, and repair history, into consideration. This paper develops a kernelized PIM (KPIM) by combining the PIM and the kernel method to consider a scenario where a repairable system experiences piecewise operating conditions. The kernel method is used to approximate the PIM covariate function nonlinearly. An approach based on the regularized likelihood function is proposed to obtain the optimal parameters for the KPIM. A numerical example is provided to demonstrate the KPIM model, and the parameter estimation approach

  • 18. Fuqing, Yuan
    et al.
    Kumar, Uday
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Predicting time to failure using support vector regression2010Inngår i: Proceedings of the 1st international workshop and congress on eMaintenance, Luleå tekniska universitet , 2010, s. 223-226Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Support Vector Machine (SVM) is a new but prospective technique which has been used in pattern recognition, data mining, etc. Taking the advantage of Kernel function, maximum margin and Lanrangian optimization method, SVM has high application potential in reliability data analysis. This paper introduces the principle and some concepts of SVM. One extension of regular SVM named Support Vector Regression (SVR) is discussed. SVR is dedicated to solve continuous problem. This paper uses SVR to predict reliability for repairable system. Taking an equipment from Swedish railway industry as a case, it is shown that the SVR can predict (Time to Failure) TTF accurately and its prediction performance can outperform Artificial Neural Network (ANN).

    Fulltekst (pdf)
    FULLTEXT01
  • 19.
    Fuqing, Yuan
    et al.
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Kumar, Uday
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Proportional Intensity Model considering imperfect repair for repairable systems2013Inngår i: International Journal of Performability Engineering, ISSN 0973-1318, Vol. 9, nr 2, s. 163-174Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The Proportional Intensity Model (PIM) extends the classical Proportional Hazard Model (PHM) in order to deal with repairable systems. This paper develops a more general PIM model which uses the imperfect model as baseline function. By using the imperfect model, the effectiveness of repair has been taken into account, without assuming an "as-bad-as-old" or an "as-good-as-new" scheme. Moreover, the effectiveness of other factors, such as the environmental conditions and the repair history, is considered as covariant in this PIM. In order to solve the large number parameters estimation problem, a Bayesian inference method is proposed. The Markov Chain Monte Carlo (MCMC) method is used to compute the posterior distribution for the Bayesian method. The Bayesian Information Criterion (BIC) is employed to perform model selection, namely, selecting the baseline function and remove the nuisance factors in this paper. In the final, a numerical example is provided to demonstrate the proposed model and method. 

    Fulltekst (pdf)
    FULLTEXT01
  • 20. Fuqing, Yuan
    et al.
    Kumar, Uday
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Statistical index development from time domain for rolling element bearings2014Inngår i: International Journal of Performability Engineering, ISSN 0973-1318, Vol. 10, nr 3, s. 313-324Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Feature extraction is crucial to efficiently diagnose fault. This paper discusses a number of time-domain statistical features, including Kurtosis or the Crest Factor, the Mean by Deviation Ratio (MDR), and Symbolized Sequence Shannon Entropy (SSSE). The SSSE reflects the spatial distribution of the signal which is complementary with the statistical features. A new feature, Normalized Normal Negative Likelihood (NNNL), is used to improve the Normal Negative Likelihood (NNL). A Separation Index (SI) called the Extended SI (ESI) evaluates the performance of each feature and to remove noise feature. The Multi-Class Support Vector Machine (MSVM) recognizes bearing defect patterns. A numerical case is presented to demonstrate these features, their feature subset selection method and the pattern recognition method. The MSVM is used to detect three different types of bearing defects: defects in the inner race, outer race and bearing ball

  • 21.
    Fuqing, Yuan
    et al.
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Kumar, Uday
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Galar, Diego
    Luleå tekniska universitet, Drift, underhåll och akustik.
    A comparative study of artificial neural networks and support vector machine for fault diagnosis2013Inngår i: International Journal of Performability Engineering, ISSN 0973-1318, Vol. 9, nr 1, s. 49-60Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Fault detection is a crucial step in condition based maintenance requiring. The importance of fault diagnosis necessitates an efficient and effective failure pattern identification method. Artificial Neural Networks (ANN) and Support Vector Machines (SVM) emerging as prospective pattern recognition techniques in fault diagnosis have been showing its adaptability, flexibility and efficiency. Regardless of variants of the two techniques, this paper discusses the principle of the two techniques, and discusses their theoretical similarity and difference. Eventually using the commonest ANN, SVM, a case study is presented for fault diagnosis using a wide used bearing data. Their performances are compared in terms of accuracy, computational cost and stability

  • 22.
    Fuqing, Yuan
    et al.
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Kumar, Uday
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Krishna, B. Misra
    Complex system reliability evaluation using support vector machine for incomplete data-set2011Inngår i: International Journal of Performability Engineering, ISSN 0973-1318, Vol. 7, nr 1, s. 32-42Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Support Vector Machine (SVM) is an artificial intelligence technique that has been successfully used in data classification problems, taking advantage of its learning capacity. In systems modelled as networks, SVM has been used to classify the state of a network as failed or operating to approximate the network reliability. Due to the lack of information, or high computational complexity, the complete analytical expression of system states may be impossible to obtain, that is to say, only incomplete data-set can be obtained.

    Using these incomplete data-sets, depending on amount of missed data-set, this paper proposes two different approaches named rough approximation method and simulation based method to evaluate system reliability. SVM is used to make the incomplete data-set complete. Simulation technique is also employed in the so called simulation based approximation method. Several examples are presented to illustrate the approaches.

  • 23.
    Galar, Diego
    et al.
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Kumar, Uday
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Fuqing, Yuan
    Luleå tekniska universitet, Drift, underhåll och akustik.
    RUL prediction using moving trajectories between SVM hyper planes2012Inngår i: 2012 proceedings: Annual Reliability and Maintainability Symposium (RAMS 2011) : Reno, Nv 23-26 Jan. 2012, Piscataway, NJ: IEEE Communications Society , 2012Konferansepaper (Fagfellevurdert)
    Abstract [en]

    With increasing amounts of data being generated by businesses and researchers, there is a need for fast, accurate and robust algorithms for data analysis. Improvements in database's technology, computing performance and artificial intelligence have contributed to the development of intelligent data analysis. The primary aim of data mining is knowledge discovery, i.e. patterns in the data that lead to better understanding of the data generating process and to useful predictions.

    The knowledge that becomes available through data mining enables an asset owner to make important decisions about life cycle costs in advance. In maintenance field, CMMS (Computer maintenance management system) and CM (Condition Monitoring) are the most popular software available in the industries. Since first one stores all historical data, maintenance actions, events and ma nufacturer recommendations, second one collects and stores all critical physical parameters (vibration, temperature.) to be monitored in a regular time basis. However, converting these data into useful information is a challenge.

    The degradation process of a system may be affected by many unknown factors, such as unidentified fault modes, unmeasured operational conditions, engineering variance, environmental conditions, etc. These unknown factors not only complicate the degradation behaviors of the system, but also make it difficult to collect quality data. Due to lack of knowledge and incomplete measurements, certain important con text information (e.g. fault modes, operational conditions) of the collected data will be missing. Therefore, historical data of the system with a large variety of degradation patterns will be mixed together. With such data, learning a global model for Remaining Useful Life (RUL) prediction becomes extremely hard since the end user does not have enough and good-quality data to model properly the system.

    This has led us to look for advanced RUL prediction techniques beyond the traditional RUL prediction models. The degradation process for many engineering systems, especially mechanical systems, is irreversible unless the condition is recovered by effective maintenance actions. The irreversible degradation process does not necessarily imply that the observed features will exhibit a monotonic progression pattern during degradation. Such progression pattern is sometimes hard to model using parametric methods. Considering a degradation process involving no or limited maintenance, the process may compose of a sequence of irreversible stages (either discrete or continuous) from new to be worn out, which can be implicitly expressed by the trajectory of the measured condition data or features. Therefore, the RUL of the system can be estimated if its future degradation trend can be projected from those historical instances. In this paper, a novel RUL prediction method inspired by feature maps and SVM classifiers is proposed.

    The historical instances of a system with life-time condition data are used to create a classification by SVM hyper planes. For a test instance of the same system, whose RUL is going to be estimated, degradation speed is evaluated by computing the minimal distance defined based on the degradation trajectories, i.e. the approach of the system to the hyper plane that segregates good and bad condition data at a different time horizon. Therefore, the final RUL of a specific component can be estimated, and global RUL information can then be obtained by aggregating the multiple RUL estimations using a density estimation method.

    Proposed model develops an effective RUL prediction method that addresses multiple challenges in complex system prognostics, where many parameters are unknown. Similarities between degradation trajectories can be checked in order to enrich existing methodologies in prognostic's applications. Existing CM data for bearings will be used to verify the model.

  • 24.
    Galar, Diego
    et al.
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Kumar, Uday
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Lee, J.
    NSFI/UCR Center for Intelligent Maintenance System (IMS), University of Cincinnati, Cincinnati, OH 45221, USA.
    Zhao, W.
    NSFI/UCR Center for Intelligent Maintenance System (IMS), University of Cincinnati, Cincinnati, OH 45221, USA.
    Remaining useful life estimation using time trajectory tracking and support vector machines2012Inngår i: 25th International Congress on Condition Monitoring and Diagnostic Engineering (COMADEM 2012): 18–20 June 2012, Huddersfield, UK, IOP Publishing Ltd , 2012, artikkel-id 012063Konferansepaper (Fagfellevurdert)
    Abstract [en]

    In this paper, a novel RUL prediction method inspired by feature maps and SVM classifiers is proposed. The historical instances of a system with life-time condition data are used to create a classification by SVM hyper planes. For a test instance of the same system, whose RUL is to be estimated, degradation speed is evaluated by computing the minimal distance defined based on the degradation trajectories, i.e. the approach of the system to the hyper plane that segregates good and bad condition data at different time horizon. Therefore, the final RUL of a specific component can be estimated and global RUL information can then be obtained by aggregating the multiple RUL estimations using a density estimation method.

  • 25.
    Galar, Diego
    et al.
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Kumar, Uday
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Sandborn, P.
    CAlCe Center for Advanced life Cycle engineering, University of Maryland.
    Morant, Amparo
    Luleå tekniska universitet, Drift, underhåll och akustik.
    O&M efficiency model: A dependability approach2012Inngår i: 25th International Congress on Condition Monitoring and Diagnostic Engineering (COMADEM 2012): 18–20 June 2012, Huddersfield, UK, IOP Publishing Ltd , 2012, artikkel-id 012111Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The occurrence of equipment failures is one of the main causes of inefficiency. These events increase the operational costs and give rise to a loss of revenues or in the worst case they can even produce an accident with significant damages to people and the environment. The efficiency of the operation of an industrial installation in a given period of time has been defined use the ratio of the Dependability level achieved by the installation in a specified period of time and the sum of the corresponding Dependability and Undependability costs.

    The aim of this paper is the development of a methodology for the calculation of operating costs in industrial facilities that addresses the difficulty of performing a simple, homogeneous and objective evaluation of the operational efficiency of the industrial facility. The main obstacle to this evaluation is the lack of a method for quantifying Dependability, which to date has always been considered a purely qualitative characteristic.

  • 26.
    Galar, Diego
    et al.
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Parida, Aditya
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Kumar, Uday
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Baglee, D.
    School of Computing and Technology, University of Sunderland.
    Morant, Amparo
    Luleå tekniska universitet, Drift, underhåll och akustik.
    The measurement of maintenance function efficiency through financial KPIs2012Inngår i: 25th International Congress on Condition Monitoring and Diagnostic Engineering (COMADEM 2012): 18–20 June 2012, Huddersfield, UK, IOP Publishing Ltd , 2012, artikkel-id 012112Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The measurement of the performance in the maintenance function has produced large sets of indicators that due to their nature and disparity in criteria and objectives have been grouped in different subsets lately, emphasizing the set of financial indicators. The generation of these indicators demands data collection of high reliability that is only made possible through a model of costs adapted to the special casuistry of the maintenance function, characterized by the occultism of these costs.

  • 27.
    Galar, Diego
    et al.
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Parida, Aditya
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Kumar, Uday
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Stenström, Christer
    Luleå tekniska universitet, 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.

  • 28.
    Gupta, Suprakash
    et al.
    Banaras Hindu University, Varanasi.
    Kumar, Uday
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Maintenance resource prioritization in a production system using cost-effective importance measure2010Inngår i: Proceedings of the 1st international workshop and congress on eMaintenance, Luleå tekniska universitet , 2010, s. 196-204Konferansepaper (Fagfellevurdert)
    Abstract [en]

    For a long time now different importance measures are put to use in reliability literature for importance ranking of events/components, an integral part of reliability analysis. Commonly used importance measures account the probability of occurrence of faults and systems structure, and ignore the effect or severity of failures which is an important factor in engineering decision making. Here a new approach is proposed by evaluating an indicator, called cost-effective indicator that accounts both the component's performance and economic aspects.

    The costeffective indicator is useful in production systems where operational reliability and cost of break down are of paramount importance. Basic events/components in a fault tree are ranked as per the decreasing value of this indicator to indicate the favourable area for improvement. It is observed in the analysis that cost-effective indicator can be a handy and effective tool for inspection, maintenance and failure detection and these activities can be carried out as per the rank of the components. Upgradation of system's performance can also be done by improving components performance with relatively large values costeffective indicator.

    Fulltekst (pdf)
    FULLTEXT01
  • 29.
    Karim, Ramin
    et al.
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Parida, Aditya
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Candell, Olov
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Kumar, Uday
    Luleå tekniska universitet, Drift, underhåll och akustik.
    eMaintenance industrial applications: issues and challenges2014Inngår i: Engineering Asset Management 2011: Proceedings of the Sixth World Congress on Engineering Asset Management / [ed] Jay Lee; Jun Ni; Jagnathan Sarangapani; Joseph Mathew, New York: Encyclopedia of Global Archaeology/Springer Verlag , 2014, s. 33-40Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Achieving business excellence within industries which utilise complex technical systems requires effective and efficient maintenance. Maintenance is an important enabler of business performance. An effective maintenance strategy creates additional values in an organisation’s value-generating process. Establishing an effective and efficient maintenance process is highly dependent on supporting Information and Communication Technology (ICT) infrastructure for information logistics that facilitates maintenance decision support. eMaintenance solutions facilitates effective and efficient management and control of maintenance activities through an enhanced utilisation of computing; like;.estimation of their Remaining Useful Life (RUL); reduction of No-Fault Found (NFF); and prediction of fault. eMaintenance solutions enable a seamless integration and fusion of information services provided by information intensive systems with embedded components in order to manage increasing and extentensively distributed real‐time data collected via different data sources (e. g. sensors). Since, the emerging ‘Internet of Things’ is expecting to dramatically change information systems with inherent embedded components, eMaintenance solutions need to be adapted to this new context to fulfil the overall business requirements on an effective and efficient decision-making process; for e.g.: real‐time analysis based on real‐time data and context-aware information logistics. However, development and establishment of proper eMaintenance solutions can be facilitated through utilisation of appropriate framework which deals with real-world challenges. This paper explores some of the issues and challenges pertaining to eMaintenance industrial application.

  • 30.
    Karim, Ramin
    et al.
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Parida, AdityaLuleå tekniska universitet, Drift, underhåll och akustik.Kumar, UdayLuleå tekniska universitet, Drift, underhåll och akustik.
    Proceedings of the 2nd International Workshop & Congress on eMaintenance: Dec 12-14 Luleå, Sweden : eMaintenace: trends in technologies and methodologies, challenges, possibilities and applications2012Collection/Antologi (Annet vitenskapelig)
    Abstract [en]

    Compilation of papers presented in the technical sessions during the eMaintenance 2012. Some selected papers from the proceedings will be published in the international journals.

    The congress aims to provide a platform for discussions on the effective utilization of Information and Communication Technology (ICT) and emerging technologies in eMaintenance.

    The themes cover various areas, including data warehousing and data mining, embedded system technologies, diagnosis and prognosis, data quality, operation performance monitoring, information logistics, performance-based logistics, decision support, enterprise resource planning, data and service fusion, integrated logistics support, maintenance optimization, prognostic health management, and life cycle management.

    Fulltekst (pdf)
    FULLTEXT01
  • 31.
    Kour, Ravdeep
    et al.
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Karim, Ramin
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Parida, Aditya
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Kumar, Uday
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Applications of radio frequency identification (RFID) technology with eMaintenance cloud for railway system2014Inngår i: International Journal of Systems Assurance Engineering and Management, ISSN 0975-6809, E-ISSN 0976-4348, Vol. 5, nr 1, s. 99-106Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Radio Frequency Identification (RFID) helps automatic identification of objects using radio waves. This is not a new technology instead decades old and has been used during the World War II, when it was used by allied ground forces to track German bombers. It is a technology for wireless communication between a reader and a transponder/tag. This technology permits the transfer of data to the most diverse objects without the need for physical contact and uses intelligent barcodes to track items and have been successfully applied in military, security, healthcare, real time location tracking, vehicle identification and other areas. This paper is based on applications of radio frequency identification technology with eMaintenance cloud for railway system to analyze and visualize data of trains for the cost effective maintenance planning. Further, cloud computing is an emerging research area that can be utilised for acquiring an effective and efficient information logistics. Specifically, the widespread use of RFID will enable wagons to be tracked leading to better resource utilization, lower freight costs, and better maintenance. Therefore, it helps to provide greater control of the train carriages, making it easier to plan resources. However, RFID is a powerful tool that can help to improve industry proficiency, implementing this technology is not easy. Furthermore, operating RFID systems can be a challenging process. Thus, this paper is based on the application of RFID in the context of railway operation.

  • 32.
    Kumar, Rupesh
    et al.
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Barabady, Javad
    Center for Safe Operation in HIGH North, University of Tromsø.
    Markeset, Tore I.
    Center for Safe Operation in HIGH North, University of Tromsø.
    Kumar, Uday
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Improving maintainability in extreme cold climatic conditions2012Inngår i: International Journal of Performability Engineering, ISSN 0973-1318, Vol. 8, nr 5, s. 563-572Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The maintainability issue is critical for the successful and effective operation of any industry in the extreme cold climatic conditions as the working conditions are made very difficult by low temperature, ice, short period of daylight and lack of support facilities. The objective of this paper is to identify potential risk factors in cold conditions and to provide ergonomic guidelines to reduce risk factors and increase maintainability of industries deployed in cold climate

  • 33.
    Kumar, Uday
    et al.
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Galar, Diego
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Parida, Aditya
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Stenström, Christer
    Luleå tekniska universitet, 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.

    Fulltekst (pdf)
    FULLTEXT01
  • 34.
    Kumar, Uday
    et al.
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Galar, Diego
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Parida, Aditya
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Stenström, Christer
    Luleå tekniska universitet, 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.

    Fulltekst (pdf)
    FULLTEXT01
  • 35.
    Kumar, Uday
    et al.
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Karim, RaminLuleå tekniska universitet, Drift, underhåll och akustik.Parida, AdityaLuleå tekniska universitet, Drift, underhåll och akustik.Tretten, PhillipLuleå tekniska universitet, Drift, underhåll och akustik.
    Proceedings of the 3rd international workshop and congress on eMaintenance: June 17-18 Luleå, Sweden : eMaintenance, Trends in technologies & methodologies, challenges, possibilites and applications2014Konferanseproceedings (Fagfellevurdert)
    Abstract [en]

    Compilation of papers presented in the technical sessions during the eMaintenance 2014.

    Fulltekst (pdf)
    FULLTEXT01
  • 36.
    Kumar, Uday
    et al.
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Parida, Aditya
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Karim, Ramin
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Special issue on eMaintenance solutions and technologies: guest editorial2010Inngår i: International Journal of Systems Assurance Engineering and Management, ISSN 0975-6809, E-ISSN 0976-4348, Vol. 1, nr 3, s. 187-188Artikkel i tidsskrift (Annet vitenskapelig)
    Abstract [en]

    Guest Editorial - Special issue on eMaintenance solutions and technologies

  • 37.
    Mahmood, Yasser Ahmed
    et al.
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Ahmadi, Alireza
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Karim, Ramin
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Kumar, Uday
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Verma, Ajint
    Stord/Haugesund University College, Haugesund.
    Fransson, Niklas
    Trafikverket.
    Comparison of frequency converter outages: a case study on Swedish TPS system2012Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The purpose of this paper is to survey the unavailability of the two main types of converters used in the Swedish traction power supply (TPS) system, i.e. the rotary and the static converter. The number of outages and the outage rate has been used to analyze and compare the unavailability of rotary and static converters. The mean cumulative function (MCF) has been used to analyze the number of outages and the unavailability trends, while the forced outage rate (FOR) concept has been used to analyze the outage rates.

    The study shows that the outages due to converter failure occur at a constant rate by calendar time at most of the converter stations, while very few stations have an increasing or a decreasing rate. It has also been found that the static converters have a higher number of outages and a higher outage rate by calendar time compared to the rotary converter types.

    The results of the study show that combining the number of outages and the forced outage rate gives a better view of the converters’ performance, and provides support for the maintenance decision. In fact, using one of them alone does not reflect reality. Comparing these two indexes is also helpful in identifying the areas where extra resources are needed to improve maintenance planning and where improvements can reduce the outage in the TPS system.

    Fulltekst (pdf)
    FULLTEXT01
  • 38.
    Morant, Amparo
    et al.
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Larsson-Kråik, Per-Olof
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Kumar, Uday
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Data-driven model for maintenance decision support: A case study of railway signalling systems2016Inngår i: Proceedings of the Institution of mechanical engineers. Part F, journal of rail and rapid transit, ISSN 0954-4097, E-ISSN 2041-3017, Vol. 230, nr 1, s. 220-234Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Signalling systems ensure the safe operation of the railway network. Their reliability and maintainability directly affect the capacity and availability of the railway network, in terms of both infrastructure and trains, as a line cannot be fully operative until a failure has been repaired. The purpose of this paper is to propose a data-driven decision support model which integrates the various parameters of corrective maintenance data and to study maintenance performance by considering different RAMS parameters. This model is based on failure analysis of historical events in the form of corrective maintenance actions. It has been validated in a case study of railway signalling systems and the results are summarised. The model allows the creation of maintenance policies based on failure characteristics, as it integrates the information recorded in the various parameters of the corrective maintenance work orders. The model shows how the different failures affect the dependability of the system: the critical failures indicate the reliability of the system, the corrective actions give information about the maintainability of the components, and the relationship between the corrective maintenance times measures the efficiency of the corrective maintenance actions. All this information can be used to plan new strategies of preventive maintenance and failure diagnostics, reduce the corrective maintenance, and improve the maintenance performance.

    Fulltekst (pdf)
    fulltext
  • 39.
    Morant, Amparo
    et al.
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Wisten, Åke
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Galar, Diego
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Kumar, Uday
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Niska, Stefan
    Electrical Power systems, Trafikverket, Lulea, Sweden.
    Railway EMI impact on train operation and environment2012Inngår i: EMC Europe 2012: International Symposium on Electromagnetic Compatibillity, September 15-21, Rome, Italy, 2012Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Several studies in Sweden have looked into railway electromagnetic interference (EMI) either to discover the source of the interference or to determine if the equipment in the system is performing properly. The movement of rolling stock along an electrified track produces certain EMI events. Transient electromagnetic fields are produced in the signalling system when the train leaves the neutral section of the overhead power line and enters the powered section. These transient EM fields are mainly produced by the engine. The track’s infrastructure system has been tested for EMI events, but this phenomenon affects the surrounding environment as well, up to at least 10 meters from the track. The infrastructure is designed so that the return current from locomotives should go through the running rails, but occasionally the ground acts as a conductor, transmitting current to areas that are distant from the rail. The paper reviews the status of Swedish railways with respect to electromagnetic compatibility. This TREND project is a joint project with 7 FP EU.

    Fulltekst (pdf)
    FULLTEXT01
  • 40.
    Nadakatti, Mahantesh
    et al.
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Parida, Aditya
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Kumar, Uday
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Knowledge Based Condition Monitoring System Using Matlab2014Inngår i: Construction and Maintenance of Railway Infrastructure in Complex Environment / [ed] F. Chen; L. Gao; L.J. Wang; X.P. Cai, Bejing: China Railway Publishng House , 2014, s. 409-414Konferansepaper (Fagfellevurdert)
    Abstract [en]

    There has been a steady rise in the machine health monitoring research due to increasing complexities of the industrial machinery. Cost of the machines and machine downtime effects like production loss, maintenance expenses and reduction in overall plant productivity are the areas of concern for modern manufacturing plants. Researchers are developing newer models and algorithms to overcome new issues and challenges in the machine health monitoring using various tools and techniques for both online and off-line machine conditions. The present paper proposes an off-line knowledge based application for machine health monitoring using MATLAB. The application has modules for intelligently addressing the machinery troubleshooting problems based on vibration standard, ISO 10816. The proposed application has three modules: machinery vibration troubleshooting, vibration severity criterion and induction motor troubleshooting. The application is simple to use and modify in which, the machine faults can be detected and analyzed quickly. This will reduce the machine down-time, maintenance costs, etc., and increase the plant productivity

  • 41.
    Palo, Mikael
    et al.
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Schunnesson, Håkan
    Luleå tekniska universitet, Geoteknologi.
    Kumar, Uday
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Condition monitoring of rolling stock using wheel/rail forces2012Inngår i: The Ninth International Conference on Condition Monitoring and Machinery Failure Prevention Technologies, 2012, s. 560-568Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Railway vehicles are efficient because of the low resistance in the contact zonebetween wheel and rail. In order to remain efficient both train operators and infrastructureowners need to keep rails, wheels and vehicles in acceptable condition. Wheelwear affects the dynamic characteristics of vehicles and the dynamic force impact on the rail.

    The shape of the wheel profile affects the performance of railway vehicles in differentways. Wheel condition has historically been managed by identifying and removing wheels from service when they exceed an impact threshold.

    Condition monitoring ofrailway vehicles is mainly performed using wheel impact load detectors and truck performance detectors. These systems use either forces or stress on the rail to interpret the condition.

    This paper will show measurements taken at the research station outside Luleå innorthern Sweden. The station measures the wheel/rail forces, both lateral and vertical,at the point of contact in a curve with 484 m radius at speeds up to 100 km/h. Dataare analyzed to show differences for various wheel positions and to determine therobustness of the system.

    Fulltekst (pdf)
    FULLTEXT01
  • 42.
    Parida, Aditya
    et al.
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Kumar, Uday
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Galar, Diego
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Stenström, Christer
    Luleå tekniska universitet, 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.

  • 43.
    Parida, Aditya
    et al.
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Stenström, Christer
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Kumar, Uday
    Luleå tekniska universitet, 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.

  • 44.
    Patra, Ambika Prasad
    et al.
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Dersin, Pierre
    ALSTOM Transport Information Solutions, 92364 Meudon-la-Forêt, France.
    Kumar, Uday
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Cost Effective Maintenance Policy: A Case Study2010Inngår i: International Journal of Performability Engineering, ISSN 0973-1318, Vol. 6, nr 6, s. 595-603Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The European Rail Traffic Management System (ERTMS) is a major venture initiated by the European Union in order to create an interoperable railway network within Europe. The manufacturers of the ERTMS strive to attain a competitive edge by demonstrating the efficiency of their systems. Achieving the optimal cost effectiveness is one of the significant ways to address the efficiency of the system and involves maximising the availability and minimising the life cycle cost of the system over the system life cycle. One of the important ways of maximising the cost effectiveness of the system is to optimise the maintenance policy. This paper demonstrates the estimation of the cost effectiveness of an ERTMS system. The degradation and repair process of the system is modelled by Petri-Nets. Failure, maintenance and cost data are used as parameters for the model. The model will be useful for systems that experience degradations and are subjected to imperfect maintenance.

  • 45. Patra, Ambika Prasad
    et al.
    Kumar, Uday
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Availability analysis of railway track circuits2010Inngår i: Proceedings of the Institution of mechanical engineers. Part F, journal of rail and rapid transit, ISSN 0954-4097, E-ISSN 2041-3017, Vol. 224, nr 3, s. 169-177Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Railways are expected to operate with ever increasing availability. The availability of railway systems and subsystems influences the overall operational availability. As the track circuit is a key component of railway signalling and control, it can contribute significantly to the loss of availability of the railway system. One way to increase the availability of the track circuit is by implementing a proper maintenance policy.

    In this article, Petri-nets have been used to develop models for availability analysis of the track circuit for both time-based and condition-based maintenance. A sensitivity analysis has been performed to estimate the effect of maintenance parameters on availability performance using cost-benefit analysis.

    Fulltekst (pdf)
    FULLTEXT01
  • 46. Patra, Ambika Prasad
    et al.
    Kumar, Uday
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Larsson-Kråik, Per-Olof
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Availability target of the railway infrastructure: an analysis2010Inngår i: 2010 proceedings: Annual Reliability and Maintainability Symposium : San Jose, California, USA, 25 - 28 January 2010, Piscataway, NJ: IEEE Communications Society , 2010Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The railway has been accepted as one of the most environmentally friendly modes of transport for goods and passengers. However, the railway sector is striving to increase its capacity to meet the growing demand for the transport of goods and passengers with a high level of punctuality in its services. Higher availability requires the effective operation and maintenance of infrastructure, often necessitating the implementation of cost-effective preventive maintenance strategies. Therefore, a higher availability target means higher maintenance investment. However, the question of setting the availability target for the infrastructure is not easy, as it involves many influencing decision parameters, apart from a good understanding of the network configuration and traffic density.

    Railway networks that have a smaller number of trains and a low punctuality requirement do not require higher availability targets. The aim of this paper is to estimate the availability target for railway infrastructure based on the capacity and punctuality requirements of infrastructure managers and train operating companies.

    The objectives of the paper are to develop an approach to i) estimating the capacity of the infrastructure based on the design and operational characteristics and evaluating the influence of infrastructure availability on the required capacity and ii) estimating the volume of primary and secondary delay due to failures and maintenance of the infrastructure and establishing the relationship between availability and punctuality requirements.

    To achieve these objectives, an example is presented with parameters drawn from failure, maintenance and traffic data. Finally, a model has been developed in Petri-Nets to establish a relationship between availability, capacity and punctuality. Monte Carlo simulation is used to establish the relationship. The simulation results illustrate the effect of infrastructure availability on train delays and capacity.

    Fulltekst (pdf)
    FULLTEXT01
  • 47.
    Singh, Sarbjeet
    et al.
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Kumar, Rupesh
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Kumar, Uday
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Applying human factor analysis tools to a railway brake and wheel maintenance facility2015Inngår i: Journal of Quality in Maintenance Engineering, ISSN 1355-2511, E-ISSN 1758-7832, Vol. 21, nr 1, s. 89-99Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    PurposeThis paper demonstrates three techniques to extract human factor information from specific railway maintenance tasks. It describes the techniques and shows how these tools can be applied to identify improvements in maintenance practices and workflow. Design/methodology/approachThree case studies were conducted on single group of technicians (N=19) at a railway maintenance workshop in Luleå, Sweden. Case study I examined the posture of the technicians while they were changing the brake shoes of freight wagons; the study employed the Standard Nordic Questionnaire and a videotape using the Ovako Working Posture Analysis System (OWAS). Case study II looked at maintenance repair times required to change the wheel axle on freight wagons at the workshop. A video filming method suggested by the European Agency for Safety and Health at Work was used to measure actual maintenance time. Finally, case study III considered the technicians’ (N=19) perception of work demands, their control over the work and their social support while performing maintenance tasks (brake shoe and wheel axle maintenance); to this end, the case study used a demand control support questionnaire. FindingsIn the first case study, the Standard Nordic Questionnaire confirmed that technicians at this particular railway vehicle maintenance workshop suffer from back and shoulder pain. The Ovako Working Posture Analysis showed that 21% of the working time required to fit the brake wedge and cotter pin fits into two OWAS categories: category 3, where “change is required as soon as possible,” and category 4, where “change is required immediately”. Problems stem from poor workplace layout, incorrect posture and inaccessibility of tools and components. In the second study, the video analysis indicated that the working time to change the wheel axle of a freight wagon is greatly affected by poor workplace layout. The third case study showed that the technicians have lower “psychological demands” (mean=13), “higher control over work” (mean= 16) and “high social support” (mean= 22).Practical implicationsThe objective of this study was to apply knowledge about human factors to the functional relationships between maintenance personnel, tasks and the working environment to improve safety. If the workplace layout, working posture, maintenance manuals and accessibility of tools are poorly planned, maintenance performance can be adversely affected. The results of this study should assist maintenance management to design new policies and guidelines for improving the work environment.Originality/valueThree case studies were conducted at a railway maintenance workshop in Luleå, Sweden, to collect data on how human factors affect various railway maintenance tasks.

  • 48.
    Singh, Sarbjeet
    et al.
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Kumar, Rupesh
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Kumar, Uday
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Modelling factors affecting human operator failure probability in railway maintenance tasks: an ISM-based analysis2015Inngår i: International Journal of Systems Assurance Engineering and Management, ISSN 0975-6809, E-ISSN 0976-4348, Vol. 6, nr 2, s. 129-138Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This paper investigates the factors affecting human operators’ probability of failure when performing railway maintenance tasks. The objective is to understand the interaction of the various factors and to identify driving and dependent factors. The factors are identified through a survey of the literature and ranked using a Likert scale. The reliability of measures is pretested by applying Cronbach’s alpha coefficient to responses to the questionnaire given to maintenance personnel. An interpretive structural model is presented, and factors are classified using matrice d’impacts croises-multiplication appliquéà un classement (MICMAC). The research may help maintenance management understand the interaction of factors affecting human failure probability in railway maintenance and help management devise policies and guidelines for railway maintenance related tasks.

  • 49.
    Soleimanmeigouni, Iman
    et al.
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Ahmadi, Alireza
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Letot, Christophe
    Machine Design and Production Engineering Lab, Research Institute for the Science and Management of Risks, University of Mons.
    Nissen, Arne
    Trafikverket.
    Kumar, Uday
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Cost-Based Optimization of Track Geometry Inspection2016Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Track geometry bear huge static and dynamic forces that accelerate degradation process. As a result, railway track should be inspected regularly to detect geometry faults and to plan maintenance actions in advanced. An inspection plan that minimizes track maintenance cost is highly desirable by infrastructure managers. This paper proposes constructing an integrated model to identify the optimum track geometry inspection interval. To this end, it develops a long term prediction model combining degradation, shock event, and tamping recovery models. It applies the Wiener process to model track geometry degradation, simulates shock event times using an exponential distribution, and uses a probabilistic model to model recovery after tamping. With the proposed integrated model and simulation, it is possible to identify the optimum track geometry inspection frequencies that minimize total track maintenance costs.

    Fulltekst (pdf)
    FULLTEXT01
  • 50.
    Stenström, Christer
    et al.
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Norrbin, Per
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Parida, Aditya
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Kumar, Uday
    Luleå tekniska universitet, 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.

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