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  • 1.
    Ahmadi, Alireza
    et al.
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Ghodrati, Behzad
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Rantatalo, Matti
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Optimum Failure Finding Inspection During Extended Operation Life2013Konferansepaper (Fagfellevurdert)
    Abstract [en]

    In a complex system such as railway and aviation equipment’s, it may be necessary to employ a combination of Failure Finding Inspection (FFI) and a scheduled discard task, as suggested by Reliability-Centered Maintenance (RCM). This strategy ensures an adequate level of availability of hidden functions, as well as the reduction of the risk of multiple failures to an acceptable level. However, in some situations, operators prefer to extend the discard life of components beyond their recommended life limit, due to the operational restrictions. This necessitates the definition of an optimal Failure Finding Inspection interval for the extended life period. This paper aims to provide a mathematical model for defining optimal FFI interval, during the extended period of the replacement life. A cost function (CF) is developed to identify the cost per unit of time associated with different FFI intervals, for the proposed extended period of life, i.e. postponement period. The proposed method concerns as-bad-as-old (ABAO) inspection and repairs (due to failures found by inspection). It considers inspection and repair times, and takes into account the costs associated with inspection and repair, the opportunity cost of lost production due to maintenance downtime created by inspection and repair actions, and also the cost of accidents due to the occurrence of multiple failure

    Fulltekst (pdf)
    FULLTEXT01
  • 2. 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.

  • 3.
    Ahmadi, Alireza
    et al.
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Soleimanmeigouni, Iman
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Letot, Christopher
    Machine Design and Production Engineering Unit, Research Institute for the Science and Manage ment of Risks, University of Mons.
    Block, Jan
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Inspection Optimization under imperfect maintenance performance2017Inngår i: Proceedings of MPMM 2016: 6th International Conference on Maintenance Performance Measurement and Management, 28 November 2016, Luleå, Sweden / [ed] Diego Galar, Dammika Seneviratne, Luleå: Luleå tekniska universitet , 2017, s. 139-Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Scheduled maintenance and inspection development is one of the main requirements for emergency equipment and safety devices. These types of devices have hidden functions which are used intermittently or infrequently, so their failure will not be evident to the operating crew. The analytical model presented in this paper deals with the periodically tested units with overhauls (preventive maintenance) after certain number of inspections and a renewal after a series of overhauls. The cost based optimization method presented in this paper identifies the optimum interval and frequency of Failure Finding Inspection (FFI) and restoration. In the proposed model, repair due to failures found by inspection makes the unit As Bad As Old, and restoration/overhaul action rejuvenates the unit to any condition between As Good As New and As Bad As Old. As Good As New effectiveness also is considered for renewal action. It considers inspection and repair times, and takes into account the costs associated with inspection, repair, restoration, and also the cost of accidents due to the occurrence of multiple failure. The results show that when the unit is not under aging process, the optimal alternative for each inspection interval is the one with highest possible number of inspection without restoration. Finally, it is observed that when the cost of accident is quite high it is needed to perform inspections at smaller intervals to control the risk of accident.

    Fulltekst (pdf)
    FULLTEXT01
  • 4.
    Al-Douri, Yamur
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Two-Level Multi-Objective Genetic Algorithm for Risk-Based Life Cycle Cost Analysis2019Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Artificial intelligence (AI) is one of the fields in science and engineering and encompasses a wide variety of subfields, ranging from general areas (learning and perception) to specific topics, such as mathematical theorems. AI and, specifically, multi-objective genetic algorithms (MOGAs) for risk-based life cycle cost (LCC) analysis should be performed to estimate the optimal replacement time of tunnel fan systems, with a view towards reducing the ownership cost and the risk cost and increasing company profitability from an economic point of view. MOGA can create systems that are capable of solving problems that AI and LCC analyses cannot accomplish alone.

    The purpose of this thesis is to develop a two-level MOGA method for optimizing the replacement time of reparable system. MOGA should be useful for machinery in general and specifically for reparable system. This objective will be achieved by developing a system that includes a smart combination of techniques by integrating MOGA to yield the optimized replacement time. Another measure to achieve this purpose is implementing MOGA in clustering and imputing missing data to obtain cost data, which could help to provide proper data to forecast cost data for optimization and to identify the optimal replacement time.

    In the first stage, a two-level MOGA is proposed to optimize clustering to reduce and impute missing cost data. Level one uses a MOGA based on fuzzy c-means to cluster cost data objects based on three main indices. The first is cluster centre outliers; the second is the compactness and separation ( ) of the data points and cluster centres; the third is the intensity of data points belonging to the derived clusters. Level two uses MOGA to impute the missing cost data by using a valid data period from that are reduced data in size. In the second stage, a two-level MOGA is proposed to optimize time series forecasting. Level one implements MOGA based on either an autoregressive integrated moving average (ARIMA) model or a dynamic regression (DR) model. Level two utilizes a MOGA based on different forecasting error rates to identify proper forecasting. These models are applied to simulated data for evaluation since there is no control of the influenced parameters in all of the real cost data. In the final stage, a two-level MOGA is employed to optimize risk-based LCC analysis to find the optimal replacement time for reparable system. Level one uses a MOGA based on a risk model to provide a variation of risk percentages, while level two uses a MOGA based on an LCC model to estimate the optimal reparable system replacement time.

    The results of the first stage show the best cluster centre optimization for data clustering with low  and high intensity. Three cluster centres were selected because these centres have a geometry that is suitable for the highest data reduction of 27%. The best optimized interval is used for imputing missing data. The results of the second stage show the drawbacks of time series forecasting using a MOGA based on the DR model. The MOGA based on the ARIMA model yields better forecasting results. The results of the final stage show the drawbacks of the MOGA based on a risk-based LCC model regarding its estimation. However, the risk-based LCC model offers the possibility of optimizing the replacement schedule.

    However, MOGA is highly promising for allowing optimization compared with other methods that were investigated in the present thesis.

    Fulltekst (pdf)
    FULLTEXT01
  • 5.
    Al-Douri, Yamur K.
    et al.
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Hamodi, Hussan
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Lundberg, Jan
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Time Series Forecasting using a Two-level Multi-objective Genetic Algorithm: A case study of cost data for tunnel fans2018Inngår i: Algorithms, E-ISSN 1999-4893, Vol. 11, nr 8, artikkel-id 123Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The aim of this study is to develop a novel two-level multi-objective genetic algorithm (GA) to optimize time series forecasting data for fans used in road tunnels by the Swedish Transport Administration (Trafikverket). The first level is for the process of forecasting time series cost data, while the second level evaluates the forecasting. The first level implements either a multi-objective GA based on the ARIMA model or based on the dynamic regression model. The second level utilises a multi-objective GA based on different forecasting error rates to identify a proper forecasting. Our method is compared with the ARIMA model only. The results show the drawbacks of time series forecasting using the ARIMA model. In addition, the results of the two-level model show the drawbacks of forecasting using a multi-objective GA based on the dynamic regression model. A multi-objective GA based on the ARIMA model produces better forecasting results. In the second level, five forecasting accuracy functions help in selecting the best forecasting. Selecting a proper methodology for forecasting is based on the averages of the forecasted data, the historical data, the actual data and the polynomial trends. The forecasted data can be used for life cycle cost (LCC) analysis.

    Fulltekst (pdf)
    FULLTEXT01
  • 6.
    Al-Douri, Yamur K.
    et al.
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Hamodi, Hussan
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Zhang, Liangwei
    Department of Industrial Engineering, School of Mechanical Engineering, Dongguan University of Technology, 523808 Dongguan, China.
    Data clustering and imputing using a two-level multi-objective genetic algorithms (GA): A case study of maintenance cost data for tunnel fans2018Inngår i: Cogent Engineering, E-ISSN 2331-1916, Vol. 5, nr 1, s. 1-16, artikkel-id 1513304Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Data clustering captures natural structures in data consisting of a set of objects and groups similar data together. The derived clusters can be used for scale analysis and to posit missing data values in objects, as missing data have a negative effect on the computational validity of models. This study develops a new two-level multi-objective genetic algorithm (GA) to optimize clustering in order to redact and impute missing cost data for fans used in road tunnels by the Swedish Transport Administration (Trafikverket). The first level uses a multi-objective GA based on fuzzy c-means to cluster cost data objects based on three main indices. The first is cluster centre outliers; the second is the compactness and separation ( ) of the data points and cluster centres; the third is the intensity of data points belonging to the derived clusters. Our clustering model is validated using k-means clustering. The second level uses a multi-objective GA to impute the missing cost redacted data in size using a valid data period. The optimal population has a low , 0.1%, and a high intensity, 99%. It has three cluster centres, with the highest data reduction of 27%. These three cluster centres have a suitable geometry, so the cost data can be partitioned into relevant contents to be redacted for imputing. Our model show better clustering detection and evaluation compared with k-means. The amount of missing data for the two cost objects are: labour 57%, materials 81%. The second level shows highly correlated data (R-squared 0.99) after imputing the missing data objects. Therefore, multi-objective GA can cluster and impute data to derive complete data that can be used for better estimation of forecasting.

  • 7. Algers, Stefan
    et al.
    Berglund, Svante
    Canella, Olivier
    Kristoffersson, Ida
    Jonsson, Daniel
    Thelin, Joacim
    Modell för bilinnehav och körkort2016Rapport (Annet vitenskapelig)
    Abstract [sv]

    Innehav av körkort och tillgång till bil är hushållsbeslut där exemeplvis hushållets samlade inkomst är en betydligt bättre förklaring till bilinnehavet än individens egen inkomst. För närvarande har vi inte prognosdata för hushåll och har därför skattat modeller baserat på individens attribut. Modellerna är formulerade som diskreta val där inkomst, demografi och zonens egenskaper spelar en stor roll. Exempel på zonegenskap är boendeform, täthet och den tillgänglighet som man uppnår med olika val av innehav av körkort och bil. De tillgänglighetmått vi använder är logsumman från efterfrågemodellerna vilket innebär att bilinnehavsmodellen är en del i den iterativa processen mellan utbud och efterfrågan. Modellen kommer på detta sätt att reagera med förändrat bilinnehav i zoner som får ändrad tillgänglighet med bil respektive utan bil. Fyra modeller för innehav av körkort och tillgång till bil har skattats : • Förekomst av bil i hushållet för personer under 18 år • Innehav av körkort • Kombinationer av bil och körkort för personer tillhörande hushåll med en vuxen • Kombinationer av bil och körkort för personer tillhörande hushåll med två eller flera vuxna.

    Fulltekst (pdf)
    Modell för bilinnehav och körkort
  • 8. Algers, Stefan
    et al.
    Berglund, Svante
    Canella, Olivier
    Kristoffersson, Ida
    Jonsson, Daniel
    Thelin, Joacim
    Pengar i Sampers2016Rapport (Annet vitenskapelig)
    Abstract [sv]

    I rapporten behandlar vi kort hanteringen av pengar i de omskattade modellerna för Sampers. Det avser kostnader, inkomster, hur modellerna reagerar på kostnader vid inkomstökning och hur dessa kan skrivas fram för ett prognosår. Hur kostnadskänsligheten hanteras i en prognossituation är central och praxis för detta bör fastställas i en bredare krets än den som skattat modellerna. I rapporten finns dock ett förslag (avsnitt 4.1). Den omskattade versionen av Sampers skiljer från tidigare versioner i två väsentliga avseenden 1) befolkningen är indelad i olika inkomstklasser och 2) nyttofunktionerna är ickelinjära i avståndsdomänen. Den senare egenskapen gör att vi i rapporten har ett förklarande avsnitt om de tidsvärden som modellerna implicerar och hur de beräknas.

    Fulltekst (pdf)
    Pengar i Sampers
  • 9. Algers, Stefan
    et al.
    Berglund, Svante
    Canella, Olivier
    Kristoffersson, Ida
    Jonsson, Daniel
    Thelin, Joacim
    Validering av omskattade regionala modeller i Sampers2016Rapport (Annet vitenskapelig)
    Abstract [sv]

    Validering har gjorts av Sampers SAMM regionala modellen för att säkerställa att det ger rimliga resultat innan kalibrering. Valideringen har gjorts genom att jämföra de följande resultat som modellen genererar med svaren från resvaneundersökningen RES 2005-2006: • Körkortsinnehav • Bilinnehav • Antal resor per ärende • Färdmedelsval • Reslängdsfördelning

    Fulltekst (pdf)
    Validering av omskattade regionala modeller i Sampers
  • 10.
    Al-Jumaili, Mustafa
    et al.
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Karim, Ramin
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Tretten, Phillip
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Multi-Criteria Data Quality Assessment Maintenance perspective2014Inngår 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; Philip Tretten, Luleå: Luleå tekniska universitet , 2014, s. 153-158Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Data quality (DQ) in maintenance has become an increasinglyimportant aspect to many firms as most of the maintenanceplanning and implementations are based on data analysis. PoorDQ has adverse effects at the operational, tactical, and strategiclevels of any organization. Respectively, poor DQ reducescustomer satisfaction, leading to poor decision making, and hasnegative impacts on strategy execution. To improve DQ as well asto evaluate the current status, DQ need to be measured followingthe fact that only what can be measured can be improved. Ameasure for DQ could be an important support for decisionmakers. In order to assess DQ, related attributes should bedefined. These attributes could be related to the data itself, to themetadata, or to the data representation schemes. After definingthese attributes, an assessment model should be used to evaluatethese attributes. The purpose of this paper is to propose a modelfor DQ assessment. Therefore, a study of DQ attributes and thepossible metrics that could be used to measure these attributes wasundertaken. The proposed model will be applied on datasetprovided by the Swedish Transport Administration (Trafikverket)for validation and to find an estimation measure of the DQ.

    Fulltekst (pdf)
    fulltext
  • 11.
    Aljumaili, Mustafa
    et al.
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Karim, Ramin
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Wandt, Karina
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Tretten, Phillip
    Luleå tekniska universitet, Drift, underhåll och akustik.
    eMaintenance Ontologies for Data Quality Support2015Inngår i: Journal of Quality in Maintenance Engineering, ISSN 1355-2511, E-ISSN 1758-7832, Vol. 21, nr 3, s. 358-374Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Purpose – The purpose of this paper is to explore the main ontologies related to eMaintenance solutions and to study their application area. The advantages of using these ontologies to improve and control data quality will be investigated.

    Design/methodology/approach – A literature study has been done to explore the eMaintenance ontologies in the different areas. These ontologies are mainly related to content structure and communication interface. Then, ontologies will be linked to each step of the data production process in maintenance.

    Findings – The findings suggest that eMaintenance ontologies can help to produce a high quality data in maintenance. The suggested maintenance data production process may help to control data quality. Using these ontologies in every step of the process may help to provide management tools to provide high quality data.

    Research limitations/implications – Based on this study, it can be concluded that further research could broaden the investigation to identify more eMaintenance ontologies. Moreover, studying these ontologies in more technical details may help to increase the understandability and the use of these standards.

    Practical implications – It has been concluded in this study that applying eMaintenance ontologies by companies needs additional cost and time. Also the lack or the ineffective use of eMaintenance tools in many enterprises is one of the limitations for using these ontologies.

    Originality/value – Investigating eMaintenance ontologies and connecting them to maintenance data production is important to control and manage the data quality in maintenance.

  • 12.
    Al-Jumaili, Mustafa
    et al.
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Mahmood, Yasser Ahmed
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Karim, Ramin
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Assessment of railway frequency converter performance and data quality using the IEEE 762 Standard2014Inngår i: International Journal of Systems Assurance Engineering and Management, ISSN 0975-6809, E-ISSN 0976-4348, Vol. 5, nr 1, s. 42694-Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Reliability, availability and maintainability analysis is one of the most important tools for measuring system performance. The performance of a traction power supply system (TPSS) can be measured using the data collected from frequency converters, as these converters constitute the main part of the TPSS. The quality of the collected data should be good enough to provide the correct and complete information necessary for assessment of frequency converter performance. Many methods can be used to assess the performance of converters such as neural networks, fuzzy logic and standards. The IEEE 762 Standard offers a methodology that can provide key performance indicators for power generation units. This standard has been chosen for its widespread acceptance and applicability. To be able to evaluate a converter’s performance, IEEE 762 indexes should be calculated using data such as the downtime, reserve shutdown hours and service hours. Therefore, the purpose of this study is to assess the performance of the Swedish TPSS frequency converters using IEEE 762, and to assess the quality of data by inspecting their compatibility with this standard. In this study, an application has been developed to generate the missing information and to calculate the indexes provided by the standard, in order to evaluate the power converters’ performance. A case with sample data is also discussed in this paper.

  • 13.
    Al-Jumaili, Mustafa
    et al.
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Rauhala, Ville
    Kemi-Tornio University of Applied Science.
    Karim, Ramin
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Jonsson, Katrin
    Department of Informatics, Umeå University.
    Parida, Aditya
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Aspects of data quality in eMaintenance: a case study of process industry in northern Europe2014Inngår i: Engineering Asset Management 2011: Proceedings of the Sixth World Congress on Engineering Asset Management / [ed] Jay Lee; Jun Ni; Jagnathan Sarangapani; Joseph Mathew, London: Encyclopedia of Global Archaeology/Springer Verlag , 2014, s. 41-51Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Increased environmental awareness in the industry combined with the globalized market economy makes increasing demands for sustainable and efficient resource utilization. In this context, maintenance plays a critical role by linking business objectives to the strategic and operational activities aimed at retaining the system’s availability performance, cost-efficiency and sustainability. Performing maintenance effectively and efficiently requires corresponding infrastructure for decision-support provided through eMaintenance solutions. A proper eMaintenance solution needs to provide services for data acquisition, data processing, data aggregation, data analysis, data visualization, context-sensing etc. To en Quality of Service (QoS) in eMaintenance solutions, the performance of both system-of-interest, enabling systems and related processes have to be measured and managed. However, the QoS has to be considered on all aggregation levels and encompass the aspects of Content Quality (CQ), Data Quality (DQ) and Information Quality (IQ). Hence, the purpose of this paper is to study and describe some aspects of DQ in eMaintenance related to process industry in northern Europe

  • 14.
    Al-Jumaili, Mustafa
    et al.
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Rauhala, Ville
    Kemi-Tornio University of Applied Science Technology, Kemi, Finland.
    Tretten, Phillip
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Karim, Ramin
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Data quality in eMaintenance: a call for research2011Inngår i: MPMM 2011: Maintenance Performance Measurement & Management: Conference Proceedings / [ed] Diego Galar; Aditya Parida; Håkan Schunnesson; Uday Kumar, Luleå: Luleå tekniska universitet , 2011, s. 69-73Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Effective and efficient maintenance requires a proper information logistics, which can be delivered through eMaintenance solutions. Development of eMaintenance solutions faces extensive challenges. One of these challenges is how to ensure the quality of data used in different eMaintenance solutions. Data Quality (DQ) concerns all phases of the maintenance process.

    The purpose of this paper is to answer the research question: How should DQ be considered and managed when developing eMaintenance solutions?

    To deal with such challenges a case study was conducted at a mining company. Empirical data has been collected through interviews, observations, archival records and workshops.

    The data analysis has been based on an empirical framework that supports the identification of required information services. Conditions that support the DQ and the information logistics, along with that, support the maintenance process have been presented. These aspects have also been related to the phases of a generic maintenance process.

    Fulltekst (pdf)
    FULLTEXT01
  • 15.
    Al-Jumaili, Mustafa
    et al.
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Wandt, Karina
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Karim, Ramin
    Luleå tekniska universitet, Drift, underhåll och akustik.
    eMaintenance ontologies and data production2012Inngår i: Proceedings of the 2nd International Workshop & Congress on eMaintenance: Dec 12-14 Luleå, Sweden : eMaintenace: trends in technologies and methodologies, challenges, possibilities and applications / [ed] Ramin Karim; Aditya Parida; Uday Kumar, Luleå: Luleå tekniska universitet , 2012, s. 191-196Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The demands on the integrity and interoperability of data in maintenance are constantly increasing. For many enterprises,achieving these demands in their operation and maintenance processes is challenging. In order to enable informationexchange between systems and their actors, using effectively andefficiently usable way, there are two essential issues which need to be addressed: i) content structure - which addresses with the description of the content’s inherent elements and also the relationship between these elements; and ii) communication interface – which addresses the interface through which each specific content will be exposed.

    There are a lot of eMaintenance ontologies which may help to solve these issues.The aim of this paper is to: i) explore the main ontologies related to eMaintenance solutions and to inspect how Data Quality (DQ) aspect is considered within these ontologies; ii) propose a process called “Maintenance Data Production” and to find the relation between ontologies and their role during data production stages.

    Fulltekst (pdf)
    FULLTEXT01
  • 16.
    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
  • 17. Andersson, Henrik
    et al.
    Swärdh, Jan-Erik
    Ögren, Mikael
    Värdering av ekvivalenta och maximala trafikbullernivåer – Svensk sammanfattning2015Rapport (Annet vitenskapelig)
    Abstract [sv]

    Denna sammanfattning baseras på FUD-projektet ”värdering av maximala trafikbullernivåer” finansierat av Trafikverket. Sammanfattningen baseras på CTS Working Paper nr 2015:11 (Andersson, m.fl., 2015), vilket är den vetenskapliga engelskspråkiga publikation som är huvudresultatet av projektet. Studien tar avstamp i problematiken kring hur trafikbuller värderas i samhällsekonomiska analyser. Traditionellt i Sverige värderas trafikbuller baserat på bullermåttet ekvivalentnivå som är ett slags viktat genomsnitt över dygnets 24 timmar. Vidare baseras den skattade betalningsviljan på en så kallad hedonisk modell där variationen i bullerexponeringen för olika villor antas fångas in i dess försäljningspriser. Det problem som kan föreligga när ekvivalentnivån används som bullermått är att vissa toppar inte värderas och att den totala bullerkostnaden därmed inte fångas in av de skattade parametrarna. Syftet med denna studie är att empiriskt skatta den marginella betalningsviljan för trafikbuller där bullret mäts som både ekvivalentnivå och maxnivå. Vi skattar en hedonisk modell och såvitt vi känner till är detta den första hedoniska studien som undersöker bullerkostnaden för både ekvivalentnivå och maxnivå samtidigt. Dessutom undersöker vi buller från både väg- och järnvägstrafik, dock i separata analyser.

    Fulltekst (pdf)
    Värdering av ekvivalenta och maximala trafikbullernivåer – Svensk sammanfattning
  • 18.
    Andersson, Petra
    et al.
    RISE - Research Institutes of Sweden (2017-2019), Safety.
    Arvidson, Magnus
    RISE - Research Institutes of Sweden (2017-2019), Safety.
    Evegren, Franz
    RISE - Research Institutes of Sweden (2017-2019), Safety.
    Jandali, Mourhaf
    RISE - Research Institutes of Sweden (2017-2019), Safety.
    Larsson, Fredrik
    RISE - Research Institutes of Sweden (2017-2019), Elektronik.
    Rosengren, Max
    RISE - Research Institutes of Sweden (2017-2019), Safety.
    Lion Fire: Extinguishment and mitigation of fires in Li-ion batteries at sea2018Rapport (Annet vitenskapelig)
    Abstract [en]

    The shipping industry is facing increasing pressure to cut emissions. Diesel-electric hybrid or fully electrical propulsion systems can offer significant savings in fuel consumption and reduce emissions. However, the use of energy storage battery systems on board vessels is introducing new fire hazards and advice on suitable fire extinguishing systems and agents is desired. In a series of tests, both total compartment application water spray and water mist systems and direct injection (using several different agents) into the module were evaluated in fire tests conducted to compare different fire extinguishing approaches for a fire in a battery cell. A test compartment was constructed to simulate a battery room and a commercially available lithium-ion (Li-ion) battery cell was positioned inside a cubic box that mimicked a battery module. By heating the battery cell, combustible gases were generated, and these gases were ignited by a pilot flame inside the simulated battery module. The tests indicated that fire extinguishment of a battery cell fire inside a battery module is unlikely when using total compartment water spray or water mist fire protection systems. The water droplets are simply not able to penetrate the battery module and reach to the seat of the fire. Direct injection of the fire extinguishing agent inside the battery module is necessary. The tests also showed that agents such as water and low-expansion foam, with a high heat capacity, provide rapid cooling and fire extinguishment. The reduced water surface tension associated with low-expansion foam may improve the possibilities for water penetration whilst agents with a high viscosity may not be able to spread to the seat of the fire. Agents with less heat capacity, such as high-expansion foam and nitrogen gas, provide less cooling but fire extinguishment can still be achieved if designed correctly.

    Fulltekst (pdf)
    FULLTEXT01
  • 19.
    Andersson, Petra
    et al.
    RISE - Research Institutes of Sweden (2017-2019), Safety.
    Arvidson, Magnus
    RISE - Research Institutes of Sweden (2017-2019), Safety.
    Evegren, Franz
    RISE - Research Institutes of Sweden (2017-2019), Safety.
    Jandali, Mourhaf
    RISE - Research Institutes of Sweden (2017-2019), Safety.
    Larsson, Fredrik
    RISE - Research Institutes of Sweden (2017-2019), Elektronik.
    Rosengren, Max
    RISE - Research Institutes of Sweden (2017-2019), Safety.
    Lion Fire: Extinguishment and mitigation of fires in Li-ion batteries at sea2018Rapport (Annet vitenskapelig)
    Abstract [en]

    The shipping industry is facing increasing pressure to cut emissions. Diesel-electric hybrid or fully electrical propulsion systems can offer significant savings in fuel consumption and reduce emissions. However, the use of energy storage battery systems on board vessels is introducing new fire hazards and advice on suitable fire extinguishing systems and agents is desired. In a series of tests, both total compartment application water spray and water mist systems and direct injection (using several different agents) into the module were evaluated in fire tests conducted to compare different fire extinguishing approaches for a fire in a battery cell. A test compartment was constructed to simulate a battery room and a commercially available lithium-ion (Li-ion) battery cell was positioned inside a cubic box that mimicked a battery module. By heating the battery cell, combustible gases were generated, and these gases were ignited by a pilot flame inside the simulated battery module. The tests indicated that fire extinguishment of a battery cell fire inside a battery module is unlikely when using total compartment water spray or water mist fire protection systems. The water droplets are simply not able to penetrate the battery module and reach to the seat of the fire. Direct injection of the fire extinguishing agent inside the battery module is necessary. The tests also showed that agents such as water and low-expansion foam, with a high heat capacity, provide rapid cooling and fire extinguishment. The reduced water surface tension associated with low-expansion foam may improve the possibilities for water penetration whilst agents with a high viscosity may not be able to spread to the seat of the fire. Agents with less heat capacity, such as high-expansion foam and nitrogen gas, provide less cooling but fire extinguishment can still be achieved if designed correctly.

    Fulltekst (pdf)
    FULLTEXT01
  • 20.
    Arasteh Khouy, Iman
    et al.
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Larsson-Kråik, Per-Olof
    Trafikverket. Luleå tekniska universitet, Drift, underhåll och akustik.
    Nissen, Arne
    Trafikverket.
    Juntti, Ulla
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Schunnesson, Håkan
    Luleå tekniska universitet, Geoteknologi.
    Optimisation of track geometry inspection interval2014Inngår 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 5, s. 546-556Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The measurement and improvement of track quality are key issues in determining the time at which railway maintenance must be performed and its cost. Efficient track maintenance ensures optimum allocation of limited maintenance resources which has an enormous effect on maintenance efficiency. Applying an appropriate tamping strategy helps reduce maintenance costs, making operations more cost-effective and leading to increased safety and passenger comfort levels. This paper discusses optimisation of the track geometry inspection interval with a view to minimising the total ballast maintenance costs per unit traffic load. The proposed model considers inspection time, the maintenance-planning horizon time after inspection and takes into account the costs associated with inspection, tamping 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 find the probability distribution of geometry faults.

  • 21.
    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.

  • 22.
    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.

  • 23.
    Arasteh Khouy, Iman
    et al.
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Schunnesson, Håkan
    Luleå tekniska universitet, Geoteknologi.
    Juntti, Ulla
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Nissen, Arne
    Larsson-Kråik, Per-Olof
    Trafikverket. Luleå tekniska universitet, Drift, underhåll och akustik.
    Evaluation of track geometry maintenance for heavy haul railroad in Sweden: a case study2014Inngår 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 5, s. 496-503Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The measurement and improvement of track quality are key issues in determining both the restoration time and cost of railway maintenance. Applying the optimal tamping strategy helps reduce maintenance costs, making operations more cost effective and leading to increased safety and passenger comfort. In this paper, track geometry data from the iron ore line (Malmbanan) in northern Sweden, which handles both passenger and freight trains, are used to evaluate track geometry maintenance in cold climate. The paper describes Trafikverket’s (Swedish Transport Administration) tamping strategy and evaluates its effectiveness in measuring, reporting, and improving track quality. Finally, it evaluates the performance of the maintenance contractor and discusses the importance of the functional requirements stated in the outsourcing contracts.

  • 24.
    Asplund, Matthias
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Wayside Condition Monitoring Technologies for Railway Systems2014Licentiatavhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    The railway is an important mode of transport, due to its environmental friendliness, high safety level, and low energy consumption, among other reasons. Railways provide a sustainable means of transporting a large amount of freight and passengers, in a cost-effective and comfortable way. The railway system has a large number of stakeholders and a small improvement in the system will give many advantages, including financial savings and an increase in the quality of service. The Swedish railway network is old and there has been almost no expansion of the network during the past few decades. There is currently a demand for more track capacity and there are no more tracks availably at the network; therefore, the existing network is expected to deliver more capacity.The railway operators are the largest cause of train delays and wheel failures are one major contributor of the delays caused by operators. The infrastructure manager is the second largest owner of train delays, and a large contributor of their train delays is switches and crossings (S&Cs). This thesis shows proposals for how condition monitoring technology can be used more efficiently for both the infrastructure and the rolling stock to increase the reliability of their critical items by decreasing train delay. Firstly, the condition of the wheel-rail interface is important, in that a bad wheel influences the rail and vice versa. The monitoring of rail profiles is already in use, but the monitoring of wheel profiles is still in the development phase. This thesis shows the performance of a wheel profile measurement system (WPMS) for an extreme climate, and a case study of performance measures such as the accuracy and reliability of the system is presented. An additional topic dealt with is how the information from the WPMS can be combined with that from the wheel defect detectors to find early indications of wheels with bad behaviour. Secondly, the S&C is an essential component of a railway system in that it increases the flexibility by diverting traffic, but S&Cs need adequate support to work properly. A camera-monitoring method for S&Cs is presented which increases the inspection frequency and decreases the human activities on the track and the train delay. In conclusion, this thesis shows that the WPMS investigated works well with a high level of performance concerning measurement accuracy and reliability in an extreme climate, and that there is still some potential for improving the system. The combination of the WPMS and wheel defect detectors shows that wheels with a high flange height have a higher probability of ending up as wheels suffering from failures. A new maintenance limit for the flange height can reduce the number of wheel defects on the track. Camera-monitoring of the S&C will increase the availability and reliability of this item and even reduce the time on the track required for the maintenance action “check” through fewer inspections and maintenance actions. These proposed monitoring techniques can improve the railway system reliability by reducing the consequential train delay times, by decreasing the number of failures of wheels and S&Cs.

    Fulltekst (pdf)
    FULLTEXT01
  • 25.
    Asplund, Matthias
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Wayside Condition Monitoring Technologies for Railway Systems2014Licentiatavhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    The railway is an important mode of transport, due to its environmental friendliness, high safety level, and low energy consumption, among other reasons. Railways provide a sustainable means of transporting a large amount of freight and passengers, in a cost-effective and comfortable way. The railway system has a large number of stakeholders and a small improvement in the system will give many advantages, including financial savings and an increase in the quality of service. The Swedish railway network is old and there has been almost no expansion of the network during the past few decades. There is currently a demand for more track capacity and there are no more tracks availably at the network; therefore, the existing network is expected to deliver more capacity.The railway operators are the largest cause of train delays and wheel failures are one major contributor of the delays caused by operators. The infrastructure manager is the second largest owner of train delays, and a large contributor of their train delays is switches and crossings (S&Cs). This thesis shows proposals for how condition monitoring technology can be used more efficiently for both the infrastructure and the rolling stock to increase the reliability of their critical items by decreasing train delay. Firstly, the condition of the wheel-rail interface is important, in that a bad wheel influences the rail and vice versa. The monitoring of rail profiles is already in use, but the monitoring of wheel profiles is still in the development phase. This thesis shows the performance of a wheel profile measurement system (WPMS) for an extreme climate, and a case study of performance measures such as the accuracy and reliability of the system is presented. An additional topic dealt with is how the information from the WPMS can be combined with that from the wheel defect detectors to find early indications of wheels with bad behaviour. Secondly, the S&C is an essential component of a railway system in that it increases the flexibility by diverting traffic, but S&Cs need adequate support to work properly. A camera-monitoring method for S&Cs is presented which increases the inspection frequency and decreases the human activities on the track and the train delay. In conclusion, this thesis shows that the WPMS investigated works well with a high level of performance concerning measurement accuracy and reliability in an extreme climate, and that there is still some potential for improving the system. The combination of the WPMS and wheel defect detectors shows that wheels with a high flange height have a higher probability of ending up as wheels suffering from failures. A new maintenance limit for the flange height can reduce the number of wheel defects on the track. Camera-monitoring of the S&C will increase the availability and reliability of this item and even reduce the time on the track required for the maintenance action “check” through fewer inspections and maintenance actions. These proposed monitoring techniques can improve the railway system reliability by reducing the consequential train delay times, by decreasing the number of failures of wheels and S&Cs.

    Fulltekst (pdf)
    FULLTEXT01
  • 26.
    Asplund, Matthias
    et al.
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Famurewa, Stephen Mayowa
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Rantatalo, Matti
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Condition monitoring and e-maintenance solution of railway wheels2014Inngår i: Journal of Quality in Maintenance Engineering, ISSN 1355-2511, E-ISSN 1758-7832, Vol. 20, nr 3, s. 216-232Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Purpose – The purpose of this paper is to investigate the failure-driven capacity consumption of wheels on the track, to determine whether there are some relations to vehicle wheel configurations that show a larger amount of failures, and to ascertain the influence of the temperature and the travelling direction of the train on the number of events. This information can be used to develop prognostic health management (PHM) so that more track capacity can be gained without modifications, re-building or re-investments. Design/methodology/approach – This paper presents a study of 1,509 warning and alarm events concerning train wheels. The data come from the infrastructure manager’s wheel defect detectors and wheel profile measurement system. These data have been analysed and processed to find patterns and connections to different vehicles, travelling directions and temperatures. Findings – Lower temperatures increase the probability of wheels having high vertical forces. Trains with different wheel configurations show different results. With high vertical forces, the probability of wheel failures at axle 6 and 7 is high for locomotives with two bogies and three axles in each bogie (2x3). All these findings can be used to develop the maintenance, monitoring and inspection principles for wheels. Practical implications – The inspection of wheels to detect failures needs to be more frequent on days and in seasons with lower temperatures. The wheel inspection should be performed more frequently at axle 6 and 7 for locomotives with a 2x3 wheel configuration. The inspection and monitoring of wheels need to be carried out more carefully for trains travelling south, to avoid a large amount of wheels with high force levels rolling in the southern direction. Originality/value – The analysis carried out in this paper identifies important factors that correlate with the high occurrence of wheel defects. It also proposes a conceptual e-maintenance model for the combination of wheel condition monitoring data from different system. The value of this study is the provision of information to support prognostic and health management system to support proactive maintenance.

  • 27.
    Asplund, Matthias
    et al.
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Famurewa, Stephen Mayowa
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Rantatalo, Matti
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Data quality assessment of automatic wheel profile measurement systems2016Inngår 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. 717-738Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The aim of this paper is to present a method for the quality assessment of data from a condition monitoring system for rolling stock wheels to ascertain if the data have the right quality to be used for further analyses. This quality assessment will also show if there are variations between different measurement units for the same system, and if there are relations between different wheel parameter measurements, speed and time. The assessment of data is accomplished using the quality dimension freedom of error. There are two different data sources, namely an automatic wheel profile measurement system and a manual wheel profile measurement device. The manual measurements of wheel profiles are used for verifying the accuracy of the automatic wheel profile measurements, which constitute the larger data set. The proposed method for evaluating the data quality is demonstrated using the data from a specific condition monitoring system. The results show some inconsistencies indicating that this system lacks quality in the dimension of freedom of error and that there is need for internal calibration or self-adjustment of the studied system for quality reasons.

  • 28.
    Asplund, Matthias
    et al.
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Famurewa, Stephen Mayowa
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Rantatalo, Matti
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Prognostic and health management of wheel condition: integration of wheel defect detection and wheel profile monitoring data2012Inngår i: Proceedings of the 2nd International Workshop & Congress on eMaintenance: Dec 12-14 Luleå, Sweden : eMaintenace: trends in technologies and methodologies, challenges, possibilities and application / [ed] Ramin Karim; Adyita Parida; Uday Kumar, Luleå: Luleå tekniska universitet , 2012, s. 15-22Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The need for proactive maintenance is increasing within railway infrastructure management due to the capacity requirement. The business environment of railway transport could be described as a multi-stakeholder model which requires intelligent infrastructure with monitoring capability of the operation to facilitate sustainable transport system. The demand to support and extend the design life time of railway infrastructure as well as their dependability during the life is also another concern which requires adequate management of the maintenance process. An approach to meet this challenge and demands is implementing proactive maintenance strategy, in which prognostic health management of wheel condition is an integral part.

    This article presents different monitoring system deployed in the railway transport, the monitoring system include wayside and on-board equipment. A case study of the wheel defects records from the detection system on the iron ore line of the Swedish transport administration is presented where the trends are shown and analysed. The development of the wheel condition monitoring, from only wheel defects detection to both wheel defects detection and wheel profile measurement is discussed.

    Finally the need for e-maintenance solution, to facilitate the anticipated prognostic aspect in wheel condition measurement is elaborated. This will support effective maintenance decisions that are required for a competitive and sustainable transport system which in turn enhances inherent network capacity.

    Fulltekst (pdf)
    FULLTEXT01
  • 29.
    Asplund, Matthias
    et al.
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Gustafsson, Per
    SWECO Energuide AB.
    Nordmark, Thomas
    LKAB.
    Rantatalo, Matti
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Palo, Mikael
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Famurewa, Stephen Mayowa
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Wandt, Karina
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Reliability and measurement accuracy of a condition monitoring system in an extreme climate: a case study of automatic laser scanning of wheel profiles2014Inngår 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. 695-704Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The Iron Ore Line (Malmbanan) is a 473 km long track section located in northern Sweden and has been in operation since 1903. This track section stretches through two countries, namely Sweden and Norway, and the main part of the track runs on the Swedish side, where the owner is the Swedish Government and the infrastructure manager is Trafikverket (the Swedish Transport Administration). The ore trains are owned and managed by the freight operator and mining company LKAB. Due to the high axle load exerted by transportation of the iron ore, 30 tonnes, and the high demand for a constant flow of ore and pellets, the track and wagons must be monitored and maintained on a regular basis. The condition of the wagon wheel is one of the most important aspects in this connection, and here the wheel profile plays an important role. For this reason an automatic laser-based wheel profile monitoring system (WPMS) has been installed on this line using a system lifecycle approach that is based on the reliability, availability, maintainability and safety (RAMS) approach for railways. The system was prepared and installed and is being operated in a collaborative project between the freight operator and infrastructure manager. The measurements are used to diagnose the condition of the wheels, and to further optimize their maintenance. This paper presents a study of the concepts and ideas of the WPMS, and the selection, installation and validation of the equipment using a system lifecycle approach that is based on RAMS for railways. Results from the profile measurements and validation are shown. The system’s reliability during performance in extreme climate conditions, with severe cold and large quantities of snow, is presented. Then the benefits, perceived challenges and acquired knowledge of the system are discussed, and an improved V-model for the lifecycle approach is presented.

  • 30.
    Asplund, Matthias
    et al.
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Nordmark, Thomas
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Gustafsson, Per
    Comparison of TOR lubrication systems on the iron ore line2015Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The Iron Ore Line (IOL) is a 473 km long track section which is located in northern Sweden and northern Norway, and has been in operation since 1903. The northern part is located above the Arctic Circle. The IOL is mainly used to transport iron ore and pellets from the mines in Kiruna and Malmberget to Narvik Harbour (Norway) in the northwest and Luleå Harbour (Sweden) in the southeast. The track section on the Swedish side is owned by the Swedish Government and managed by Trafikverket (the Swedish Transport Administration), while the ore wagons are owned and managed by the freight operator (LKAB).The IOL has seen a considerable increase in the axle load and traffic volume recently. Due to the introduction of new vehicles with a 30-ton axle load, the rails were gradually replaced between 2006 and 2009 with heavier rails, generally with a steel grade of 350LHT. The rail and wheels suffer from rolling contact fatigue (RCF) due to high friction between the rail and wheel. To control the wheel-rail interface, wayside top-of-rail (TOR) lubrication can be used. The reliability of the TOR lubrication equipment and the lubricants in northern conditions has not been investigated, and the long-term maintenance support required for TOR lubrication is unknown to the infrastructure manager. Furthermore, can TOR lubrication reduce the rail and wheel maintenance costs? This project has been conducted through collaboration between the main operator (LKAB) and the infrastructure manager (Trafikverket); the costs have been shared and the results analysed in collaboration. This paper describes the test period of two years, using two different TOR lubrication systems in two different places on the IOL, one situated in the northern loop and one in the southern loop, each with different operational conditions. The paper shows the actual operational conditions for the pilot test locations, the friction value close to the systems, the rail forces during the test period and some results for the noise measurements. Furthermore, the paper includes the improvements of system resulting from the test operation, and ends with recommendations for the continued use of TOR lubrication on the IOL.

    Fulltekst (pdf)
    fulltext
  • 31.
    Asplund, Matthias
    et al.
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Nordmark, Thomas
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Gustafsson, Per
    Comparison of TOR lubrication systems on the iron ore line2015Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The Iron Ore Line (IOL) is a 473 km long track section which is located in northern Sweden and northern Norway, and has been in operation since 1903. The northern part is located above the Arctic Circle. The IOL is mainly used to transport iron ore and pellets from the mines in Kiruna and Malmberget to Narvik Harbour (Norway) in the northwest and Luleå Harbour (Sweden) in the southeast. The track section on the Swedish side is owned by the Swedish Government and managed by Trafikverket (the Swedish Transport Administration), while the ore wagons are owned and managed by the freight operator (LKAB).The IOL has seen a considerable increase in the axle load and traffic volume recently. Due to the introduction of new vehicles with a 30-ton axle load, the rails were gradually replaced between 2006 and 2009 with heavier rails, generally with a steel grade of 350LHT. The rail and wheels suffer from rolling contact fatigue (RCF) due to high friction between the rail and wheel. To control the wheel-rail interface, wayside top-of-rail (TOR) lubrication can be used. The reliability of the TOR lubrication equipment and the lubricants in northern conditions has not been investigated, and the long-term maintenance support required for TOR lubrication is unknown to the infrastructure manager. Furthermore, can TOR lubrication reduce the rail and wheel maintenance costs? This project has been conducted through collaboration between the main operator (LKAB) and the infrastructure manager (Trafikverket); the costs have been shared and the results analysed in collaboration. This paper describes the test period of two years, using two different TOR lubrication systems in two different places on the IOL, one situated in the northern loop and one in the southern loop, each with different operational conditions. The paper shows the actual operational conditions for the pilot test locations, the friction value close to the systems, the rail forces during the test period and some results for the noise measurements. Furthermore, the paper includes the improvements of system resulting from the test operation, and ends with recommendations for the continued use of TOR lubrication on the IOL.

    Fulltekst (pdf)
    fulltext
  • 32.
    Asplund, Matthias
    et al.
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Nordmark, Thomas
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Gustafsson, Per
    Pallari, Robert
    Mining Technology R and D, LKAB Kiruna Mine.
    Larsson, Dan
    Damill AB, Luleå, Damill AB.
    Karim, Ramin
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Slutrapport avseende hjulprofilmätare i Sunderbyn2014Rapport (Annet vitenskapelig)
    Abstract [sv]

    Bakgrunden till projektets genomförande har varit den ökande mängden rälsbyten och mängden trafik med 30 tons axellast på Malmbanan. Spårunderhållet och hjulunderhållet har idag de överlägset högsta underhållskostnaderna av järnvägens olika system. Hjulprofilmätaren sågs som en möjlighet att kunna plocka ut de hjul som närmade sig underhållsgränserna för slitage, och därigenom kunna styra underhållet mer kostnadseffektivt.LKAB och Trafikverket enades därför att sätta upp ett gemensamt projekt där en ny typ av mätutrustning utprovades. För att få stöd med datalagring, bearbetning av data mm anlitades LTU och eMaintenanceLAB. Syftet med projektet har varit att undersöka och verifiera att en utrustning för automatisk hjulprofilmätning kan klara av att registrera och larma vid hjulpassager som avviker från de säkerhetsgränser och underhållsgränser som definieras i projektet med hänsyn till vårt klimat och våra förhållanden på Malmbanan. Den bärande idén i detta projekt har varit att man genom en kontinuerlig mätning av hjulprofiler ska kunna ta ut fordon ur trafik innan den avvikande hjulprofilen ger upphov till ett accelererande hjul- och rälslitage och därigenom sänka underhållskostnaden och öka livslängden på både hjul och räl. Projektet har även lett till en högre säkerhet på spåret då man kan mäta hjul som passerat säkerhetsgränsen för hjulparametrar och plockar bort dem, detta var inte var möjligt tidigare. De slutsatser som kan dras från detta projekt är följande:• Utvecklingsprojekt kan med fördel genomföras gemensamt mellan industri, infrastrukturförvaltare och akademi. • För att säkerställa ett bra resultat är det viktigt att genomföra alla steg i ett projekt från koncept till överlämnande. Som stöd för detta har V-modellen används som representerar livscykeln för systemet enligt EN-50126.• Val av tekniklösning och leverantör har gjorts utifrån tekniknivå, referensanläggningar samt drift- och supportmöjlighet och inte enbart utifrån pris. Ett utvecklingsprojekt likt detta handlar inte primärt om att få en utrustning i drift utan överföring av ”know how” kring vilka möjligheter och begränsningar det finns med denna teknik.• Resursbehovet för test och utvärdering underskattades och gjorde att projektet försenades ett år jämfört med ursprunglig tidplan. • Informationen som genereras från denna utrustning är mycket användbar för alla parter som arbetar med utveckling av underhåll inom järnvägen. • Utmaningen för att tillgodogöra sig nyttan från mätstationen ligger i att kunna förädla och integrera de genererade tillståndsdata till respektive underhållsorganisation.

    Fulltekst (pdf)
    FULLTEXT01
  • 33.
    Asplund, Matthias
    et al.
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Nordmark, Thomas
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Gustafsson, Per
    Pallari, Robert
    Mining Technology R and D, LKAB Kiruna Mine.
    Larsson, Dan
    Damill AB, Luleå, Damill AB.
    Karim, Ramin
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Slutrapport avseende hjulprofilmätare i Sunderbyn2014Rapport (Annet vitenskapelig)
    Abstract [sv]

    Bakgrunden till projektets genomförande har varit den ökande mängden rälsbyten och mängden trafik med 30 tons axellast på Malmbanan. Spårunderhållet och hjulunderhållet har idag de överlägset högsta underhållskostnaderna av järnvägens olika system. Hjulprofilmätaren sågs som en möjlighet att kunna plocka ut de hjul som närmade sig underhållsgränserna för slitage, och därigenom kunna styra underhållet mer kostnadseffektivt.LKAB och Trafikverket enades därför att sätta upp ett gemensamt projekt där en ny typ av mätutrustning utprovades. För att få stöd med datalagring, bearbetning av data mm anlitades LTU och eMaintenanceLAB. Syftet med projektet har varit att undersöka och verifiera att en utrustning för automatisk hjulprofilmätning kan klara av att registrera och larma vid hjulpassager som avviker från de säkerhetsgränser och underhållsgränser som definieras i projektet med hänsyn till vårt klimat och våra förhållanden på Malmbanan. Den bärande idén i detta projekt har varit att man genom en kontinuerlig mätning av hjulprofiler ska kunna ta ut fordon ur trafik innan den avvikande hjulprofilen ger upphov till ett accelererande hjul- och rälslitage och därigenom sänka underhållskostnaden och öka livslängden på både hjul och räl. Projektet har även lett till en högre säkerhet på spåret då man kan mäta hjul som passerat säkerhetsgränsen för hjulparametrar och plockar bort dem, detta var inte var möjligt tidigare. De slutsatser som kan dras från detta projekt är följande:• Utvecklingsprojekt kan med fördel genomföras gemensamt mellan industri, infrastrukturförvaltare och akademi. • För att säkerställa ett bra resultat är det viktigt att genomföra alla steg i ett projekt från koncept till överlämnande. Som stöd för detta har V-modellen används som representerar livscykeln för systemet enligt EN-50126.• Val av tekniklösning och leverantör har gjorts utifrån tekniknivå, referensanläggningar samt drift- och supportmöjlighet och inte enbart utifrån pris. Ett utvecklingsprojekt likt detta handlar inte primärt om att få en utrustning i drift utan överföring av ”know how” kring vilka möjligheter och begränsningar det finns med denna teknik.• Resursbehovet för test och utvärdering underskattades och gjorde att projektet försenades ett år jämfört med ursprunglig tidplan. • Informationen som genereras från denna utrustning är mycket användbar för alla parter som arbetar med utveckling av underhåll inom järnvägen. • Utmaningen för att tillgodogöra sig nyttan från mätstationen ligger i att kunna förädla och integrera de genererade tillståndsdata till respektive underhållsorganisation.

    Fulltekst (pdf)
    FULLTEXT01
  • 34.
    Asplund, Matthias
    et al.
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Palo, Mikael
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Famurewa, Stephen Mayowa
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Rantatalo, Matti
    Luleå tekniska universitet, Drift, underhåll och akustik.
    A study of railway wheel profile parameters used as indicators of an increased risk of wheel defects2016Inngår 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. 323-334Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The capacity demands on the railways will increase in the future, as well as the demands for a robust and available system. The availability of the railway system is dependent on the condition of the infrastructure and the rolling stock. To inspect the rolling stock and to prevent damage to the track due to faulty wheels, infrastructure managers normally install wayside monitoring systems along the track. Such systems indicate, for example, wheels that fall outside the defined safety limits and have to be removed from service to prevent further damage to the track. Due to the nature of many wayside monitoring systems, which only monitor vehicles at definite points along the track, damage may be induced on the track prior to fault detection at the location of the system. Such damage can entail capacity-consuming speed reductions and manual track inspections before the track can be opened for traffic again. The number of wheel defects must therefore be kept to a minimum. In this paper wheel profile parameters measured by a wayside wheel profile measurement system, installed along the Swedish Iron Ore Line, are examined and related to warning and alarm indications from a wheel defect detector installed on the same line. The study shows that an increased wheel wear, detectable by changes in the wheel profile parameters could be used to reduce the risk of capacity-consuming wheel defect failure events and its reactive measures.

  • 35.
    Asplund, Matthias
    et al.
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Palo, Mikael
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Famurewa, Stephen Mayowa
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Rantatalo, Matti
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Larsson-Kråik, Per-Olof
    Trafikverket. Luleå tekniska universitet, Drift, underhåll och akustik.
    Condition monitoring of rolling stock wheels: approach towards maintenance decision making2014Inngår i: 27th International Congress on Condition Monitoring and Diagnostic Engineering (COMADEM 2014): 16 - 18 September 2014, Brisbane Convention and Exhibition Centre, Australia, COMADEM International , 2014Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Due to the more or less fixed inherent capacity of a railway system, capacity consuming events like failures within a railway network should be kept to a minimum. This could be achieved by the use of existing and new condition monitoring systems which can detect, report and predict failure events in an early stage. Demands for higher service quality, higher capacity, network availability and track quality together with less human intervention on tracks, drive the development of railway condition monitoring systems.Failure driven capacity consumption due to worn or defected rolling stock wheels have a big impact on the capacity and the infrastructure condition. Wheel defects such as out-of-round wheels, generates high forces, and could result in large capacity consumption especially for areas with cold climate conditions. Bad wheels cause even higher track wear that reduce the life length of the track. Wheels with fatigue defects could also influence the track safety issues. This paper presents how different wheel defects can be monitored; together with a review of the most common wayside condition monitoring systems on the Swedish railway network. The study also describes how the decision making process could take advantage of the condition monitoring data in order to increase the achieved network capacity.

  • 36.
    Asplund, Matthias
    et al.
    Trafikverket. Luleå tekniska universitet, Drift, underhåll och akustik.
    Palo, Mikael
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Famurewa, Stephen Mayowa
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Rantatalo, Matti
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Larsson-Kråik, Per-Olof
    Trafikverket. Luleå tekniska universitet, Drift, underhåll och akustik.
    Condition monitoring of rolling stock wheels: approach towards maintenance decision making2014Inngår i: 27th International Congress on Condition Monitoring and Diagnostic Engineering (COMADEM 2014): 16 - 18 September 2014, Brisbane Convention and Exhibition Centre, Australia, COMADEM International , 2014Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Due to the more or less fixed inherent capacity of a railway system, capacity consuming events like failures within a railway network should be kept to a minimum. This could be achieved by the use of existing and new condition monitoring systems which can detect, report and predict failure events in an early stage. Demands for higher service quality, higher capacity, network availability and track quality together with less human intervention on tracks, drive the development of railway condition monitoring systems.Failure driven capacity consumption due to worn or defected rolling stock wheels have a big impact on the capacity and the infrastructure condition. Wheel defects such as out-of-round wheels, generates high forces, and could result in large capacity consumption especially for areas with cold climate conditions. Bad wheels cause even higher track wear that reduce the life length of the track. Wheels with fatigue defects could also influence the track safety issues. This paper presents how different wheel defects can be monitored; together with a review of the most common wayside condition monitoring systems on the Swedish railway network. The study also describes how the decision making process could take advantage of the condition monitoring data in order to increase the achieved network capacity.

  • 37.
    Asplund, Matthias
    et al.
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Rantatalo, Matti
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Johnsson, Roger
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Hiensch, Martin
    Combating curve squeal noise2016Inngår i: Combating curve squeal noise, 2016Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Society demand for more sustainable transports is increasing, starting a modal shift from road to railway. The resulting increase in railway traffic intensity is leading to more activities on the track, even during the night time. For many years continuous urbanization has been resulting in a higher density of residents in areas close to railway tracks. The combination of these factors is raising the issue of noise disturbances from railway transports, which is forcing infrastructure managers to take action to combat noise from railway traffic systematically. There are different types of noise emanating from railways and one of the most annoying is curve squeal noise. This paper deals with the curve squeal phenomenon, the places where it occurs, and different methods for reducing it. The curving behaviour of a vehicle plays an important role in the generation of curve squeals, and therefore the way in which different rail profiles affect the capability to steer in a sharp curve is dealt within this paper. The paper is based on two case studies with investigated curves in urban regions that suffer from squeal noise, and in which comparisons between measurements and simulations were performed. The outcome of these studies is a workflow for combating squeal noise, results concerning the effects of a top-of-rail friction modifier on noise mitigation, and a proposed rail profiles for improving the steering capability of vehicles.

  • 38.
    Asplund, Matthias
    et al.
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Schoech, Wolfgang
    Speno International.
    Towards perfected rail maintenance: combining routine and long-term research activities2015Konferansepaper (Fagfellevurdert)
    Abstract [en]

    In 2007 the new grinding strategy with “Malmbanan”, Europe’s only heavy-haul railway, has been presented at the IHHA-conference in Kiruna. Four years later an update was given, as in between some adaptations concerning the target profiles and the metal removal requirements have been introduced. The monitoring process on selected test sections using MiniProf- and Eddy-current devices never stopped and provided since valuable understanding of the effect of applying optimized specifications. This was particular important in view of the increasing traffic load and the hence required doubling of the yearly grinding campaigns. The combination of the once fixed routine grinding operations with the research activities resulted in a consistently good rail surface situation and revealed further insight in the complex matter of wheel-rail interaction. The latest findings and further development is presented in this article.

    Fulltekst (pdf)
    fulltext
  • 39.
    Behaderovic, Irfan
    et al.
    KTH, Byggteknik och design.
    Khaled, Nora
    KTH, Byggteknik och design.
    Temperaturmätningar i inklädnadssystem och sprutbetong inom Norra länken2019Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [sv]

    Just nu pågår stora anläggningsprojekt i Stockholm där Trafikverket försöker leda om trafiken från stadskärnan. Därför utfördes projektet Norra länken. Norra länkens tunnelkonstruktion är uppbyggd med ett inklädnadssystem och bergförstärkning som består av sprutbetong. I nuläget saknas information om vilka temperaturer som uppstår i en tunnelkonstruktion och på grund av detta appliceras Trafikverkets generella antagande vid dimensionering av vägtunnlar. Antagandet säger att tunnelkonstruktionens temperatur kommer att motsvara uteluftstemperaturen. Vilket innebär att sprutbetongen behöver vara frostbeständig och därmed appliceras XF4 eller XF2. För att förstå temperaturförhållandet i tunnelkonstruktioner bättre har Trafikverket utfört mätningar i Norra länken. Med ökad förståelse för temperaturförhållandena skulle det vara möjligt att korrigera det nuvarande kraven på exponeringsklasserna. Därmed var syftet med denna rapport att undersöka om mätningarna kunde hjälpa till att utforma ett underlag för framtida val av exponeringsklass i kommande tunnelprojekt med liknade inklädnadssystem. Metoden som användes för att kunna undersöka frågeställningarna var litteraturstudier, studiebesök och analys av mätningarna i Excel. Resultatet visade att bergförstärkningens temperatur aldrig hamnade under 0℃ under perioden som mätningarna erhölls medan inklädnadens temperatur understeg 0℃. Detta innebar att det inte fanns risk för frostskador i bergförstärkningen men att i inklädnaden fanns det risk för det. Däremot när analysen gjordes noterades att två av tre mätstationer blivit vattenskadade och orsakat mycket felaktig data och att all mätdata som erhölls var från milda vintrar. Vilket bidrar till att det finns en osäkerhet kring hur pålitliga mätvärdena var. Från analysen togs slutsatserna att det fanns för lite underlag för att kunna ta beslutet om att ändra val av exponeringsklass inför kommande tunnelprojekt och att Trafikverkets antagande inte stämde. Där av rekommenderas Trafikverket att fortsätta med mätningarna till planerat slutdatum 2025 och på så sätt erhålla tillräckligt med information för att i framtiden kunna utvärdera exponeringsklasserna på nytt.

    Fulltekst (pdf)
    FULLTEXT01
  • 40. Berg, Eva
    et al.
    Norrman, Andreas
    Näslund, Dag
    Systematiska och processorienterade mätsystem: En teoriöversykt2016Rapport (Annet vitenskapelig)
    Abstract [sv]

    Rapporten är en teoriöversikt över systematiska mätsystem och hur de kan utformas med hänsyn till olika perspektiv, såsom strategi, process, försörjningsnätverk och anläggning, men också för att ge en integrerad helhetssyn. Rapporten identifierar intressanta fördjupningsområden för framtida forskningsområden i uppdrag av Trafikverket. Med ett kritiskt förhållningssätt har en systematisk genomgång av litteraturen gjorts. Litteraturstudien pekar på att det finns problem med terminologin och standardisering av vad som menas med systematiska mätsystem. Trots att forskning kring mätsystem har bedrivits under lång tid är problembilden den samma idag som för tjugo år sedan och få konkreta lösningar på dessa problem har forskats fram. Det finns konceptuella modeller kring design och implementering av mätsystem, men det finns lite forskning kring användning av mätsystem och dess effekter på organisationen. Ur ett akademiskt perspektiv innebär det att mätsystem är inte är ett etablerat forskningsområde. Det finns med andra ord brister i teoribasen, brister i utvärderingen av mätsystemen, brister i empiri och kvalitet när det gäller forskningen. I praktiken innebär det att det är en liten koppling mellan teori och praktik. Det finns ett analytiskt synsätt snarare än en systemsyn. Konceptuellt finns en stark koppling mellan strategi och mätsystemet, men i praktiken finns det brister i kopplingen och få empiriska bevis. Processorientering är underutvecklat och kartläggningen av processer ignoreras. Det brister även i kopplingen mellan intressenter och mätsystemet. Speciellt ur ett kund- eller medborgarfokus. Det finns också lite fokus på förändringsarbete och vilka framgångsfaktorer som medför lyckade utformningar och implementeringar av mätsystem. Trafikverket är till stor del beroende av underleverantörer för att leverera sin prestation. Det är därför relevant att mäta också påverkan och prestation av partners och leverantörer. Denna ansats, att mäta i försörjningskedjor med en systemansats, har börjat uppmärksammas inom logistikforskningen de senaste femton åren. Denna forskning har för övrigt samma grundperspektiv, och kan tillskrivas samma kritik, som övrig forskning. Det finns framtida forskningsbehov kring både implementera och utvärdera mätsystem samt i högre grad testa och bevisa konceptuella modeller empiriskt. Det finns också ett behov av större teori- och metoddriven forskning. Att utforma processorienterade mätsystem med ett underliggande försörjnings- och systemsynsätt, kan vara länken till att stärka kopplingen mellan strategier, mätsystemet och dess effekt.

    Fulltekst (pdf)
    Systematiska och processorienterade mätsystem: En teoriöversykt
  • 41. Biswal, Munro
    et al.
    Parida, Aditya
    Luleå tekniska universitet, Drift, underhåll och akustik.
    An integrated approach for open e-Maintenance2010Inngår i: Proceedings of the 1st international workshop and congress on eMaintenance, Luleå tekniska universitet , 2010, s. 107-114Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The present day e-maintenance space is evolving with isolated legacy sub-systems or packages that span heterogeneous and domain specific industry verticals. Developing a unified platform for e-maintenance catering to the varied domains shall hence pose a major challenge.

    An open systems based platform for emaintenance can overcome some of these hurdles by defining the otherwise disparate systems as abstract entities with well defined public interfaces. The interfaces can be broadly classified based on the technology types, thus allowing individual vertical emaintenance applications to align with their respective business interests. In all, this shall greatly help in reducing the overall operating costs and at the same time provide increased flexibility, reusability and reliability.

    The underlying standard protocol, defined through a group consensus, shall be responsible for transport of the e-maintenance data between the distributed subsystems via the TCP/IP standard within multiple administrative domains of e-maintenance across wired and wireless networks.

    This paper also looks at e-maintenance from a systems integration perspective and illustrates how open systems based approach can help achieve integration better.

    Fulltekst (pdf)
    FULLTEXT01
  • 42.
    Björling, Sten-Erik
    Luleå tekniska universitet, Drift, underhåll och akustik.
    Integration of knowledge management systems and end-user interfaces for MPMM2011Inngår i: MPMM 2011: Maintenance Performance Measurement & Management: Conference Proceedings / [ed] Diego Galar; Aditya Parida; Håkan Schunnesson; Uday Kumar, Luleå: Luleå tekniska universitet , 2011, s. 209-212Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Maintenance can be considered as a combined information and knowledge processing and management system. Effective knowledge, practices and experiences management is growing in importance, especially in advanced processes and management of advanced and expensive assets. Efforts of integrating maintenance knowledge management (MKM) processes with MKMM will be increasingly more important due to the increasing complexities of these overall systems – the context in which the performance measurements has been performed is also important input in the performance analysis. Integration of MKM in MPMM can result in higher quality of the decisions and actions in the maintenance processes and in the overall work to increase efficiency and decreasing costs in the organizations.

    Integration of MKM (Maintenance Knowledge Management – knowledge, experiences and practices management) with collaborative structures and interfacing abilities with qualified services for simulation, modeling and computations can be regarded as Intelligence-based Maintenance (iMaintenance).

    These infrastructures present in iMaintenance can further improve MPMM efforts due to possible utilization of more accurate property and context information and services – changes in installations, environmental factors etc. not easily integrated in current MPMM implementations.Integration of MPMM with iMaintenance solutions can also improve the interaction between management and the maintenance operators and also allow improved interaction and integration with production operators in the organization. MPMM can with this approach be integrated as a natural component in the overall ICT-based maintenance and collaboration solutions – the performance status reporting will be seen as a natural extension to the normal routines. In this context the usability of the end-user environments will be very important – especially when designing systems for mobile use by maintenance operators in the field.

    Fulltekst (pdf)
    FULLTEXT01
  • 43. Bröchner, Jan
    et al.
    Eriksson, Per-Erik
    Kadefors, Anna
    Gustavsson, Tina Karrbom
    Lind, Hans
    Hur skapas drivkrafter till effektivitet och innovation? En studie av incitamentsbaserade ersättningsformer och deras effekter.2015Rapport (Annet vitenskapelig)
    Abstract [sv]

    Den här studien behandlar incitamentsbaserade ersättningsformer. Genom litteraturstudier och intervjuer med representanter från tre av Trafikverkets projekt studeras hur incitamentsbaserade ersättningsformer kan användas och vad de kan ge för effekter. Studien ger en översikt av de olika metoder som finns för att minska riskerna för moral Hazardproblem och öka drivkrafterna för ömsesidigt samarbete i byggprojekt. I studien diskuteras också tre olika typer av incitamentsbaserad ersättningsform: ekonomiskt incitament kopplad till riktkostnad, fast entreprenörsarvode, samt bonusbaserat incitament. Ekonomiskt incitament kopplad till riktkostnad är den vanligaste typen av incitamentsbaserad ersättningsform och den innebär att både beställare och entreprenör får drivkrafter att arbeta gemensamt för att öka effektivitet och göra innovationer som sänker projektkostnaderna. Intervjuerna visar att frågor som rör riktkostnader är mycket viktiga att ta hänsyn till. Det gäller bl a processen för att fastställa riktkostnader, hur riktkostnader och riktkostnadsändringar hanteras under kontraktstiden och vilka spelregler som bör gälla för justering av riktkostnaden. Studien visar också att inkluderandet av konsulten i incitamentsavtalet upplevs vara betydelsefullt, men att det samtidigt är svårt att få önskad effekt.

    Fulltekst (pdf)
    Hur skapas drivkrafter till effektivitet och innovation? En studie av incitamentsbaserade ersättningsformer och deras effekter.
  • 44. Bärthel, Fredrik
    et al.
    Hammarbäck, Lennart
    Olovsdotter, Ann-Mari
    Sommar, Robert
    Södergren, Christer
    Shortlines – affärsmodeller för ökad tillgänglighet till kostnadseffektiv regional järnvägsservice2014Rapport (Annet vitenskapelig)
    Abstract [sv]

    Syftet med projektet är att genomföra en undersökning av förutsättningarna, möjligheterna och utmaningarna med att etablera järnvägsföretag enligt short line-principen på den svenska marknaden – som underleverantör till nationella eller internationella järnvägsföretag samt för egen regional järnvägsservice. Rapporten har som mål att visa om det finns marknads- och produktionsförutsättningar för en liknande gynnsam utveckling i Sverige som förekommit i USA och på så sätt skapa möjligheter för en trafik som annars kanske skulle lagts ned eller inte funnits. Om det är möjligt skapar det positiva systemeffekter inom järnvägssystemet, där de större järnvägsföretagen skulle kunna koncentrera sina utvecklingsinsatser på lönsamma heltåg och samtidigt behålla tillgängligheten för mindre transportköpare till järnvägstrafik och därmed även möjlighet till fortsatt och kanske utvecklad konkurrens mellan lastbil och järnväg samt inte minst leda till ökad lönsamhet inom järnvägssektorn.

    Fulltekst (pdf)
    Shortlines – affärsmodeller för ökad tillgänglighet till kostnadseffektiv regional järnvägsservice
  • 45.
    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
  • 46. Canella, Olivier
    et al.
    Flötteröd, Gunnar
    Johnsson, Daniel
    Kristoffersson, Ida
    Larek, Patryk
    Thelin, Joacim
    Flexible coupling of disaggregate travel demand models and network simulation packages2016Rapport (Annet vitenskapelig)
    Abstract [en]

    Trafikverket’s development plan states as one of eleven expected results “En ny generation persontransportmodellsystem, med dynamisk modell för storstad implementerad” (Trafikverket, 2014). IHOP aims to be this system. IHOP2 is the second development project advancing the IHOP system. IHOP2 couples the travel demand model Regent and the network assignment package TransModeler through a new, agent-based interface layer that is based on the MATSim transport simulation toolkit. The main objective of this effort is to demonstrate that such a coupling is feasible. This demonstration is delivered based on a prototypical Stockholm case study. The present document is also meant to serve as a technical documentation of the IHOP system in its current form. This project has been funded by Trafikverket under contract TRV2015/2950.

    Fulltekst (pdf)
    Flexible coupling of disaggregate travel demand models and network simulation packages
  • 47. Cars, Göran
    et al.
    Engström, Carl-Johan
    Sverigeförhandlingen och sedan? II: Följeforskarnas iakttagelser, reflektioner och propåer2016Rapport (Annet vitenskapelig)
    Abstract [sv]

    Hur kan arbetsmetoder och processer utvecklas? Vi föreslår att — kommande förhandlingsprocesser läggs upp efter en modell där förhandlingsprocessen beskrivs i fyra faser. Modellen bör utvecklas i samverkan mellan Trafikverket och SKL. — att kommande förhandlingar med liknande syfte som Sverigeförhandlingen organiseras så att kommunsfärens förhandlingsaktörer utgörs av en konstellation av kommuner inom en funktionell region som tillsammans kan åta sig att genomföra sin del av förhandlingsöverenskommelsen gentemot staten. — kunskaps- och utbildningsinsatser, motsvarande dem som Trafikverket har genomfört, initieras för kommunala och regionala företrädare inför förhandlingar av den typ som introducerats av Sverigeförhandlingen. Hur kan förhandlingsresultaten integreras i ordinarie planering? Vi föreslår att — de slutliga formella avtalen också innehåller en fastlagd uppföljningsmekanism och en fortsatt förhandlingsordning, som rymmer kontrollstationer där frågor successivt låses i objektsavtal. — att bansträckningar prövas i ett sammanhang av regeringen inom institutionen tillåtlighetsprövning. En utredning bör tillsättas för att klarlägga de mer detaljerade förutsättningarna för ett sådant förfarande. — Trafikverket utreder den mekanism för omhändertagande av resultatet som följer på ett eventuellt riksdagsbeslut i frågan. Det gäller särskilt aspekter som hur prioriteringen av nödvändiga följdinvesteringar ska göras utan att undanträngningseffekterna av andra investeringar, underhåll och trimningsåtgärder får menliga effekter. Hur kan förhandlingar som planeringsform institutionaliseras? Vår slutsats är att förhandling som metod i första hand bör tillämpas i sammanhang där det finns en brett förankrad syn på kopplingen mellan potentiella åtgärder och nyttor och för frågor där de förhandlande parternas intressen och inflytande är så jämbördigt som möjligt. Samt att det därför finns anledning att utgå från eftersträvad funktion snarare än objekt i förhandlingarna. Förhandlingen bör omfatta de delsystem som är väsentliga för att den tillkommande infrastrukturen ska kunna utnyttjas till fullo. Vi föreslår att — en systematisk studie av nyttor och onyttor som bör innefattas i en förhandling och lämpliga metoder för detta vidareutvecklas inom ramen för utredningsväsendet där förutsättningar finns att pröva utan bindningar varken till Sverigeförhandlingen, Trafikverket eller till nuvarande akademiska paradigm. Trafikverket bör kunna ta initiativ till en sådan studie. — den storregionala nyttan utreds mer ingående genom Trafikverkets FOI-anslag. Det är angeläget att få belyst under vilka förutsättningar en regional integration över stora avstånd kan fungera.

    Fulltekst (pdf)
    Sverigeförhandlingen och sedan? II: Följeforskarnas iakttagelser, reflektioner och propåer
  • 48. Cregård, Anna
    et al.
    Karlsson, Lars
    Montin, Stig
    Svärd, Oskar
    Implementering i en komplex miljö: förstudie av Trafikverkets implementering av beslut2015Rapport (Annet vitenskapelig)
    Abstract [sv]

    Genomgången av Trafikverkets styrdokument visar att det förekommer en mängd varierande typer av styrning och implementeringar, vilande på vitt skilda logiker. Med kvantitet avses mängden implementeringar, och både styrdokumenten och fokusgruppsintervjuerna indikerar att det är en mycket stor mängd implementeringar som förutsätts i Trafikverkets organisation. I genomgången av Trafikverkets styrdokument framträder vid en närmre genomläsning tre olika kategorier av implementering, som vilar på tre olika implementeringslogiker. Den första kategorin utgörs av implementering av regler. Den andra kategorin som framträder i Trafikverkets styrdokument är implementering av mål och resultat. Den tredje kategorin av implementering inom Trafikverket som vi har kunnat identifiera i styrdokument och under fokusgrupperna är implementering av värden och visioner. Kategoriseringen av implementering inom Trafikverket kan också göras utifrån hur tvingande de olika kategorierna av implementering är. Dessa olika typer av styrning varierar inte bara utifrån hur pass tvingande de är. I litteraturen om styrning och styrmedel diskuteras styrning och styrmedel utifrån vilka antaganden om beteenden de vilar på. Det mest påtagliga problemet när styrning som grundas i olika antaganden om beteenden används tillsammans är att dessa kan komma i konflikt med varandra. Styrning med hjälp av regler innebär en implementeringslogik, medan styrning med hjälp av resultat och mål förutsätter en annan, och styrning med hjälp av kultur och värden en tredje. Till dessa implementeringslogiker kan även läggs en fjärde, där agenten förutsätts agera professionellt. Som en följd av att det inom Trafikverket finns tre (eller fyra) olika implementeringslogiker så finns det också tre olika sätt som agenterna kan agera på, och som alla uppfattas som legitima. Problemet är dock att agerande i enlighet med en implementeringslogik kan stå i motsättning till en annan. En effekt av flera, sinsemellan motstridiga, implementeringslogiker är att det skapas en otydlighet kring vilket agerande som är lämpligt och kring hur agenterna ska agera. Genomgången indikerar att Trafikverket brottas med en mängd olika system för styrning och därmed logiker för implementering. Till det läggs en stor tilltro till rationalitet: det gäller både individens handlande och styrsystemens förmåga. Mängden styrimpulser och deras olikhet som möter medarbetare framstår som omfattande. Att dessa sedan förväntas leda till vissa resultat och också samlat, trots stor heterogenitet, ge hög måluppfyllelse, kan vara en svårighet som inte bara chefer och beslutsfattare brottas med, utan också naturligtvis medarbetare och externa aktörer. Det är inte ovanligt i stora, offentliga verksamheter, och studier visar att det mycket oftare tillkommer styrprinciper och – modeller än det plockas bort, vilket skapar trängsel inom styrkedjan och inte alltid resulterar i större överensstämmelse med fattade beslut. Detta har kommit att kallas överstyrning eller överdos av styrning. Enligt en gängse föreställning ska styrsystem och administrativa strukturer (stödsystem) vara ett stöd för kärnverksamheten, det vill säga myndighetens huvuduppgift. Kritiska granskningar av hur det går till i organisationer och myndigheter påvisar ofta att det inte är så enkelt. Inte minst under senare år när olika komponenter av det som kallas NPM har studerats (mål- och resultatstyrning, renodling i formella organisationer, den växande dokumentationen osv) har det framförts att nya styrsystem snarare hindrar än främjar det som organisationen/myndigheten huvudsakligen ska göra. Mot den bakgrunden och sett utifrån den tidigare implementationsforskningens resultat framstår det som underligt att det faktiskt fungerar så bra som det gör inom en myndighet.

    Fulltekst (pdf)
    Implementering i en komplex miljö: förstudie av Trafikverkets implementering av beslut
  • 49.
    Dahlholm, Olivia
    et al.
    Trivector Traffic AB .
    Thaddäus, Tiedje
    Trivector Traffic AB .
    Edfast, Nils
    Trivector Traffic AB .
    Anpassa staden för gods på cykel2022Rapport (Annet vitenskapelig)
    Abstract [sv]

    Rapporten är framtagen med ekonomiskt bidrag från Skyltfonden, Trafikverket. Ståndpunkter och slutsatser i rapporten reflekterar författaren och överensstämmer inte med nödvändighet med Trafikverkets ståndpunkter och slutsatser inom rapportens ämnesområde.

    I många europeiska städer pågår en utveckling med en växande mängd last- och godscyklar för ”last-mile”-leveranser. Även i Sverige ses en växande trend om än i dagsläget mer blygsam. Godscyklar är i grunden säkrare än lätta lastbilar men är samtidigt mer utrymmeskrävande, tyngre och ofta långsammare än vanliga cyklar. En ökad andel godscyklar kommer därför leda till att det blir trängre på den befintliga cykelinfrastrukturen och bland annat generera större behov av omkörningar, vilket kan innebära en ökad risk för cykelolyckor.   

    Denna vägledning redogör för de infrastrukturella förutsättningar som krävs i trafikmiljön för att säkerställa att överflyttningen av urbana godstransporter från konventionella fordon (lätta lastbilar med mera) till godscyklar sker på ett trafiksäkert sätt, både för godscyklister och för övriga trafikanter - i synnerhet cyklister och gående. Vägledningen beskriver också översiktligt trafiksäkerhetseffekterna och andra effekter av en infrastrukturanpassning till godscyklar kan generera. 

    Fulltekst (pdf)
    Anpassa staden för gods på cykel
    Download (png)
    presentationsbild
  • 50.
    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

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