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  • 51.
    Karim, Ramin
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Söderholm, Peter
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Application of information and communication technology for maintenance support information services: transferring experiences from an eHealth solution in Sweden2009Ingår i: Journal of Quality in Maintenance Engineering, ISSN 1355-2511, E-ISSN 1758-7832, Vol. 15, nr 1, s. 78-91Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Purpose - The purpose of this paper is to explore the transferability of ICT-solutions for providing support information services from eHealth to eMaintenance. Design/methodology/approach - The applied research approach takes the form of a single-case study supported by a literature study. Empirical data were collected through documents, observations and interviews. The conclusions of the study were verified by key informants. Findings - The study indicates some major problems that have to be overcome when implementing support information services using an ICT-solution (e.g. to manage heterogeneous organizations; manage heterogeneous eService-environments; and enable context and situation awareness in eServices). Further, the study has identified and graded some solutions, which address these problems and are transferable from eHealth to eMaintenance. Practical implications - The studied case is in the forefront of eHealth solutions and can therefore act as a guidance for those involved at different stages of eHealth implementation. At the same time, eHealth is an application domain with stringent safety and security requirements, which makes the findings valuable for persons involved in support information services related to complex and critical technical systems, e.g. aircraft systems. Originality/value - The paper reports on experiences from an actual eHealth solution and not just about the concept of eHealth. Hence, it has implications for both practitioners and researchers.

  • 52.
    Karim, Ramin
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Söderholm, Peter
    Luleå tekniska universitet, Institutionen för ekonomi, teknik och samhälle, Industriell Ekonomi.
    Kumar, Uday
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Service-oriented condition monitoring and information logistics2009Ingår i: Proceedings of CM/MFPT 2009 - (CM2009): CD Proceedings of The Sixth International Conference on Condition Monitoring and Machinery Failure Prevention Technologies - CM/MFPT 2009, held 23-25 June 2009 at the Stillorgan Park Hotel, Dublin, Ireland, Longborough, Glos.: British Institute of Non-Destructive Testing and Coxmoor Publishing , 2009, Vol. 1, s. 257-267Konferensbidrag (Refereegranskat)
    Abstract [en]

    Today the requirements on availability performance and Life Support Cost (LSC) over the system life cycle has increased and the reduction of maintenance and support cost has become more essential. To meet these requirements Condition Monitoring (CM) and Condition-Based Maintenance (CBM) can be employed. These approaches can significantly reduce Life Cycle Cost (LCC) by eliminating unnecessary inspections, minimizing inspection time and effort, and extending the useful life of new and aging components. Two important activities related to CM, that facilitates CBM, and other product support approaches, are diagnostics and its extension towards prognostics. This extension is possible thanks to new technological advances in sensors and failure analysis and is a revolution in the way complex systems can be supported. It is a breakthrough that promises not only more efficient operations and reduced maintenance cost, but also the saving of lives. However, it is not sufficient to limit the CM, diagnostic and prognostic activities to the technical systems, but the support and business systems should also be monitored and analysed to enable condition-based utilization and support of available assets and resources and fulfil ultimate performance requirements. Hence, this paper describes a service-oriented approach to CM and necessary information logistics.

  • 53.
    Karim, Ramin
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Westerberg, Jesper
    eMaintenance365 AB.
    Kumar, Uday
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Galar, Diego
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Maintenance Analytics: The New Know in Maintenance2016Ingår i: IFAC-PapersOnLine, ISSN 2405-8963, Vol. 49, nr 28, s. 214-219Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Decision-making in maintenance has to be augmented to instantly understand and efficiently act, i.e. the new know. The new know in maintenance needs to focus on two aspects of knowing: 1) what can be known and 2) what must be known, in order to enable the maintenance decision-makers to take appropriate actions. Hence, the purpose of this paper is to propose a concept for knowledge discovery in maintenance with focus on Big Data and analytics. The concept is called Maintenance Analytics (MA). MA focuses in the new knowledge discovery in maintenance. MA addresses the process of discovery, understanding, and communication of maintenance data from four time-related perspectives, i.e. 1) “Maintenance Descriptive Analytics (monitoring)”; 2) “Maintenance Diagnostic Analytics”; 3) “Maintenance Predictive Analytics”; and 4) “Maintenance Prescriptive analytics”.

  • 54.
    Kour, Ravdeep
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Al-Jumaili, Mustafa
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Karim, Ramin
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Tretten, Phillip
    Luleå tekniska universitet, Institutionen för ekonomi, teknik och samhälle. Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    eMaintenance in railways: Issues and challenges in cybersecurity2019Ingår i: Proceedings of the Institution of mechanical engineers. Part F, journal of rail and rapid transit, ISSN 0954-4097, E-ISSN 2041-3017, Vol. 233, nr 10, s. 1012-1022Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The convergence of information technology and operation technology and the associated paradigm shift toward Industry 4.0 in complex systems, such as railways has brought significant benefits in reliability, maintainability, operational efficiency, capacity, as well as improvements in passenger experience. However, with the adoption of information and communications technologies in railway maintenance, vulnerability to cyber threats has increased. It is essential that organizations move toward security analytics and automation to improve and prevent security breaches and to quickly identify and respond to security events. This paper provides a statistical review of cybersecurity incidents in the transportation sector with a focus on railways. It uses a web-based search for data collection in popular databases. The overall objective is to identify cybersecurity challenges in the railway sector.

  • 55.
    Kour, Ravdeep
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Karim, Ramin
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    E-monitoring of operation and maintenance task under difficult visual work environment2012Ingår 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. 167-171Konferensbidrag (Refereegranskat)
  • 56.
    Kour, Ravdeep
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Karim, Ramin
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Parida, Aditya
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Cloud Computing for Maintenance Performance Improvement2013Konferensbidrag (Refereegranskat)
    Abstract [en]

    Cloud Computing is an emerging research area. It can be utilised for acquiring an effective and efficient information logistics. This paper uses cloud-based technology for the establishment of information logistics for railway system which requires information based on data from different data sources (e.g. railway maintenance, railway operation, and railway business data). In order to improve the performance of the maintenance process relevant data from various sources need to be acquired, filtered, fused, integrated, and analysed for decision making and to facilitate for example, diagnostics and prognostics decisions. The process of maintenance information provisioning is highly dependent on an appropriate information logistics. In this paper the authors have tried to study the improvement in the maintenance performance of railway operations in Sweden.

  • 57.
    Kour, Ravdeep
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Karim, Ramin
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Parida, Aditya
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Kumar, Uday
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Applications of radio frequency identification (RFID) technology with eMaintenance cloud for railway system2014Ingår i: International Journal of Systems Assurance Engineering and Management, ISSN 0975-6809, E-ISSN 0976-4348, Vol. 5, nr 1, s. 99-106Artikel i tidskrift (Refereegranskat)
    Abstract [en]

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

  • 58.
    Kour, Ravdeep
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Karim, Ramin
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Thaduri, Adithya
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Cybersecurity for railways: A maturity model2019Ingår i: Proceedings of the Institution of mechanical engineers. Part F, journal of rail and rapid transit, ISSN 0954-4097, E-ISSN 2041-3017Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    With the advancements in and widespread adoption of information and communication technologies in infrastructures, cyber-attacks are becoming more frequent and more severe. Advanced cybersecurity threats with automated capabilities are increasing in such sectors as finance, health, grid, retail, government, telecommunications, transportation, etc. Cyber-attacks are also increasing in railways with an impact on railway stakeholders, e.g. threat to the safety of employees, passengers, or the public in general; loss of sensitive railway information; reputational damage; monetary loss; erroneous decisions; loss of dependability, etc. There is a need to move towards advanced security analytics and automation to identify, respond to, and prevent such security breaches. The objective of this research is to reduce cyber risks and vulnerabilities and to improve the cybersecurity capabilities of railways by evaluating their cybersecurity maturity levels and making recommendations for improvements. After assessing various cybersecurity maturity models, the Cybersecurity Capability Maturity Model (C2M2) was selected to assess the cybersecurity capabilities of railway organizations. The contributions of this research are as follows. First, a new maturity level MIL4 (Maturity Indicator Level 4) is introduced in the C2M2 model. Second, the C2M2 model is adapted by adding advanced security analytics and threat intelligence to develop the Railway-Cybersecurity Capability Maturity Model (R-C2M2). The cybersecurity maturity of three railway organizations is evaluated using this model. Third, recommendations and available standards & guidelines are provided to the three railway organizations to improve maturity levels within different domains. In addition, they are given an action plan to implement the recommendations in a streamlined way. The application of this model will allow railway organizations to improve their capability to reduce the impacts of cyber-attacks and eradicate vulnerabilities. The approach can also be extended to other infrastructures with necessary adaptations.

  • 59.
    Kour, Ravdeep
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Karim, Ramin
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Tretten, Phillip
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    EMaintenance solutions for railway maintenance decisions2015Ingår i: World Congress on Engineering, WCE 2014: London, 2 - 4 July 2014 / [ed] S.I. Ao; Len Gelman; David W.L. Hukins; Andrew Hunter; Alexander Korsunsky, Hong Kong: Newswood Limited , 2015, Vol. 1, s. 228-232Konferensbidrag (Refereegranskat)
    Abstract [en]

    The term eMaintenance emerged in the early 2000s and has become a popular topic in maintenance related literature because of ongoing technological improvements. This paper uses a recent approach, i.e. cloud-based technology, to provide an eMaintenance solution for online time data analysis to make effective and efficient railway maintenance decisions. Due to increased traffic, the Swedish railway sector needs to optimise maintenance, using predictive maintenance to a much higher degree so that unplanned breakdowns and downtime are drastically reduced. The paper shows how research within the railway sector is developing eMaintenance solutions using the cloud and web-based applications for improved condition monitoring, better maintenance and increased uptime. In the proposed solution, data are acquired from railway measurement stations and sent to the eMaintenance cloud, where they are filtered, fused, integrated and analysed to assist maintenance decisions. The paper provides a concept for a web-based eMaintenance solution to assist railway maintenance stakeholders make fact-based decisions and develop more efficient and economically sound maintenance policies.

  • 60.
    Kour, Ravdeep
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Thaduri, Adithya
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Karim, Ramin
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Railway Defender Kill Chain for Cybersecurity2019Ingår i: Proceedings of the 5th International Workshop & Congress on eMaintenance 2019, 2019Konferensbidrag (Refereegranskat)
    Abstract [en]

    The railway is one of the most important infrastructures and its security is as important as other critical infrastructures. Due to the increase in cyber-attacks, there is an increasing trend in the field of cybersecurity. The history of cyber incidents suggested that the railway needs immediate security measures or defensive controls for forthcoming advanced persistent threats (APT). Cyber Kill Chain (CKC) is one of the most widely used models for the identification, detection, and prevention of advanced persistent threats. CKC model was introduced by Lockheed Martin that consists of seven stages as Reconnaissance, Weaponize, Delivery, Exploitation, Installation, Command & Control, and Act on Objective. Breaking the chain as early as possible in the CKC model will help the defender to stop adversary’s malicious actions. As the railway is adapting digital technologies and, therefore, there is a risk that adversary can penetrate into the system following the steps of CKC. The objective of this research is to reduce the risk of cyber-attacks by proposing Railway Defender Kill Chain (RDKC) that provides security controls at each phase of Cyber Kill Chain to predict, prevent, detect and respond to cyber threats.

  • 61.
    Kour, Ravdeep
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Tretten, Phillip
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Karim, Ramin
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    eMaintenance solution through online data analysis for railway maintenance decision-making2014Ingår i: Journal of Quality in Maintenance Engineering, ISSN 1355-2511, E-ISSN 1758-7832, Vol. 20, nr 3, s. 262-275Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Purpose – The purpose of this paper is to demonstrate how research within the railway sector is developing eMaintenance solutions using the cloud and web-based applications for improved condition monitoring, better maintenance and increased uptime. This eMaintenance solution is based on the on-line data acquisition, integration and analysis leading to effective maintenance decision making.Design/methodology/approach – In the proposed methodology, data are acquired from railway measurement stations to the eMaintenance cloud, where they are filtered, fused, integrated and analyzed to assist maintenance decisions. Extensive consultation with stakeholders has resulted in the analysis of railway data.Findings – The paper provides a concept for a web-based eMaintenance solution for railway maintenance stakeholders for making fact-based decisions and develops more efficient and economically sound maintenance policies. Train wheels reaching their maintenance and safety limits are visualised in grids and graphs to assist stakeholders in making the appropriate maintenance decisions.Practical implications – In this paper the authors have demonstrated that the wheel profile and force data can be remotely collected through cloud utilization. The information generated can be used for maintenance decision making. Similarly, other measurable data can also be utilized for maintenance decision making.Originality/value – This paper describes the importance of eMaintenance solution through online data analysis to make effective and efficient railway maintenance decisions, as a case study.

  • 62.
    Kour, Ravdeep
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Tretten, Phillip
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Karim, Ramin
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Singh, Sarbjeet
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Cybersecurity Workforce in Railway: A Case Study2019Ingår i: Proceedings of the 5th International Workshop & Congress on eMaintenance 2019, 2019Konferensbidrag (Refereegranskat)
    Abstract [en]

    Railway will continue to adapt new digital solutions which are necessary and vulnerable to cyber threats. The history of cyber-attacks on critical infrastructures including railway suggests that there is a need for cybersecurity awareness. Both for employees and the general public. The very first step in cyber hygiene is cybersecurity training and awareness for the workforce. A well-educated workforce plays a vital role in building more cyber resiliency across the organization's operation and maintenance. The objective of this research is to evaluate the cybersecurity maturity level for workforce management in three railway organizations. The results show that there is a cybersecurity workforce gap and there is a need to eliminate this gap by enhancing cybersecurity workforce culture. Henceforth, this gap can be improved by developing cybersecurity culture, including cybersecurity training and awareness and by following recommendations provided in this paper.

  • 63.
    Kumar, Uday
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Karim, Ramin
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Current trends in maintenance engineering2011Ingår i: International Journal of Pedagogy, Innovation and New Technologies, ISSN 0973-1318, E-ISSN 2392-0092, Vol. 7, nr 6, s. 503-504Artikel i tidskrift (Övrigt vetenskapligt)
  • 64.
    Kumar, Uday
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Parida, Aditya
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Karim, Ramin
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Special issue on eMaintenance solutions and technologies: guest editorial2010Ingår i: International Journal of Systems Assurance Engineering and Management, ISSN 0975-6809, E-ISSN 0976-4348, Vol. 1, nr 3, s. 187-188Artikel i tidskrift (Refereegranskat)
  • 65.
    Mahmood, Yasser Ahmed
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Ahmadi, Alireza
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Karim, Ramin
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Kumar, Uday
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Verma, Ajint
    Stord/Haugesund University College, Haugesund.
    Fransson, Niklas
    Trafikverket.
    Comparison of frequency converter outages: a case study on Swedish TPS system2012Konferensbidrag (Refereegranskat)
    Abstract [en]

    The purpose of this paper is to survey the unavailability of the two main types of converters used in the Swedish traction power supply (TPS) system, i.e. the rotary and the static converter. The number of outages and the outage rate has been used to analyze and compare the unavailability of rotary and static converters. The mean cumulative function (MCF) has been used to analyze the number of outages and the unavailability trends, while the forced outage rate (FOR) concept has been used to analyze the outage rates. The study shows that the outages due to converter failure occur at a constant rate by calendar time at most of the converter stations, while very few stations have an increasing or a decreasing rate. It has also been found that the static converters have a higher number of outages and a higher outage rate by calendar time compared to the rotary converter types. The results of the study show that combining the number of outages and the forced outage rate gives a better view of the converters’ performance, and provides support for the maintenance decision. In fact, using one of them alone does not reflect reality. Comparing these two indexes is also helpful in identifying the areas where extra resources are needed to improve maintenance planning and where improvements can reduce the outage in the TPS system.

  • 66.
    Mahmood, Yasser Ahmed
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Ahmadi, Alireza
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Verma, Ajit
    Karim, Ramin
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Kumar, Uday
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Availability and reliability performance analysis of traction frequency converters: a case study2013Ingår i: International Review of Electrical Engineering, ISSN 1827-6660, Vol. 8, nr 4, s. 1231-1242Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The frequency converter is one of the main parts of the traction power supply system (TPSS) and converts adequate traction power from the power company to the electric vehicle. In the Swedish railway network, this system comprises around 133 frequency converters with a total capacity reach of 1,295 MVA and covers around 9,543 km of electrified railway. The aim of this article is to evaluate and compare the reliability, availability and maintainability (RAM) performances of the ten models of converters used in the Swedish railway system. The key performance indicators introduced by the IEEE Std 762 methodology have been used to measure and compare the RAM performance of the converters. Moreover, the mean cumulative function (MCF) has also been used for the monitoring and comparison of the field reliability of converters versus the operating time, capacity factor and converted power. The study shows that, in general, both the static and the rotary types have a high level of availability ranging from 97%-99%. The results also show that the TGTO model (a static type) has the lowest RAM performance among all the models. In addition, it has been found that using IEEE Std 762 or the MCF alone does not always provide a complete answer. Therefore, the study suggests using both the IEEE Std 762 and the MCF methodology to arrive at a more realistic result. The study has shown that the MCF based on the capacity factor gives a good result compared with the results obtained using the MCF based on the operating time and on the converted power as a measure of the usage intensity.

  • 67.
    Mahmood, Yasser Ahmed
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Karim, Ramin
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Al-Jumaili, Mustafa
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Assessment of reliability data for traction frequency converters using IEEE Std 762: a study at Swedish railway2012Ingår 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. 171-174Konferensbidrag (Refereegranskat)
  • 68.
    Morant, Amparo
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Karim, Ramin
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Larsson-Kråik, Per-Olof
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Information logistics for maintenance of railway signalling systems: A case study2013Ingår i: The international Journal of railway technology, ISSN 2049-5358, E-ISSN 2053-602X, Vol. 2, nr 2, s. 97-112Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The purpose of this paper is to explore the use of information logistics for railway signalling systems to improve the efficiency of their corrective maintenance. The signalling system is used to control, supervise and protect railway traffic; therefore, its reliability, maintainability and related maintenance support affect the availability of the railway network. The paper reviews the current status of the maintenance of railway signalling systems, looking at company surveys and company data for a specific case study and consulting relevant literature. It describes how and where data are processed and analyses corrective maintenance work orders to determine how much time is spent on corrective action and knowledge management Areas of improvement are identified and possible improvements are proposed. The efficiency of information logistics has a clear effect on the dependability of the railway signalling system. Signalling systems’ performance can be improved by having better control of and accessibility to the information required for each maintenance action.

  • 69.
    Morant, Amparo
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Karim, Ramin
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Tretten, Phillip
    Luleå tekniska universitet, Institutionen för ekonomi, teknik och samhälle.
    Galar, Diego
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Improvement of configuration management in railway signalling system2012Ingår 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 Parita; Uday Kumar, Luleå: Luleå tekniska universitet, 2012, s. 23-32Konferensbidrag (Refereegranskat)
  • 70.
    Morant, Amparo
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Karim, Ramin
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Tretten, Phillip
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Larsson-Kråik, Per-Olof
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Dependability improvement through configuration management: A study of railway signalling systems2013Ingår i: International Journal of COMADEM, ISSN 1363-7681, Vol. 16, nr 4, s. 31-40, artikel-id 4Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The reliability, maintainability and related maintenance support of signalling systems affect the railway network´s availability. Constituting a system-of-systems spread over a wide geographical area, signalling systems consist of a large number of items with different lifecycles making it a challenge to define and describe the structure and relationship between the system’s inherent items at any specific time. System configuration describes a system’s structure to which other data sources can be related. Some current research discusses asset maintenance management in the railway infrastructure, but not many holistic approach deals with signalling systems. The purpose of this paper is to investigate how the process of configuration management, can improve the dependability of the railway system. The paper presents a model for the configuration management of railway signalling systems. The model is based on the results of company surveys and interviews, data analysis and literature review. This model provides better control and visibility of the information related to the system and any changes made to it. Faster and better failure diagnostics can be performed, thus improving maintenance performance. This, in turn, provides better availability of the system by reducing the downtime of the railway network; hence, an improvement in maintainability is also achieved.

  • 71.
    Parida, Aditya
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Karim, Ramin
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Project: Key Performance Indicators for control and management of maintenance process through eMaintenance2014Övrigt (Övrig (populärvetenskap, debatt, mm))
  • 72.
    Parida, Aditya
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Karim, Ramin
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Thaduri, Adithya
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Guest Editorial2017Ingår i: Journal of Quality in Maintenance Engineering, ISSN 1355-2511, E-ISSN 1758-7832, Vol. 23, nr 3, s. 258-259Artikel i tidskrift (Övrigt vetenskapligt)
  • 73.
    Saari, Esi
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Lin, Jing
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Liu, Bin
    Department of Management Science, University of Strathclyde, Glasgow, UK .
    Zhang, Liangwei
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik. Department of Industrial Engineering, Dongguan University of Technology, Dongguan, China .
    Karim, Ramin
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Novel Bayesian Approach to Assess System Availability using a Threshold to Censor Data2019Ingår i: International Journal of Performability Engineering, ISSN 0973-1318, Vol. 15, nr 5, s. 1314-1325Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Assessment of system availability has been studied from the design stage to the operational stage in various system configurations using either analytic or simulation techniques. However, the former cannot handle complicated state changes, and the latter is computationally expensive. This study proposes a Bayesian approach to evaluate system availability. In this approach: 1) Mean Time to Failure (MTTF) and Mean Time to Repair (MTTR) are treated as distributions instead of being "averaged" to better describe real scenarios and overcome the limitations of data sample size; 2) Markov Chain Monte Carlo (MCMC) simulations are applied to take advantage of the analytical and simulation methods; and 3) a threshold is set up for Time to Failure (TTR) data and Time to Repair (TTR) data, and new datasets with right-censored data are created to reveal the connections between technical and "Soft" KPIs. To demonstrate the approach, the paper considers a case study of a balling drum system in a mining company. In this system, MTTF and MTTR are determined by a Bayesian Weibull model and a Bayesian lognormal model, respectively. The results show that the proposed approach can integrate the analytical and simulation methods to assess system availability and could be applied to other technical problems in asset management (e.g., other industries, other systems). By comparing the results with and without considering the threshold for censoring data, we show the threshold can be used as a monitoring line for continuous improvement in the investigated mining company.

  • 74.
    Szymanowski, Mårten
    et al.
    Saab Technologies.
    Candell, Olov
    Karim, Ramin
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Challenges for interactive electronic technical publications in military aviation2010Ingår i: Proceedings of the 1st international workshop and congress on eMaintenance, Luleå tekniska universitet, 2010, s. 190-195Konferensbidrag (Refereegranskat)
    Abstract [en]

    In military aviation, Technical Publications (TP) are fundamental for the establishment of a maintenance strategy and provisioning of information support and maintenance services. They are also under the supervision of military authorities. For complex technical systems such as aircraft, technical publications often contain essential information such as indenture levels, repair and replacement instructions, spare part information, configuration information, required tools and item-related maintenance information. The manufacturer is faced with the challenge of coordinating the production of the complete TP-package. Authors and illustrators must write, draw and supply meta-data to every piece of information. They must do so according to detailed specifications (e.g. ASD S1000D) and writing guides. There is also complex cross-reference handling within the TP-package to consider, e.g. from maintenance instructions to illustrated parts catalogues. Cross-references exist within the content in the same publication, to other publications and/or to external information sources, e.g. databases. The information contained in the final TP-package is equivalent to, literally, tens of thousands of A4-pages. Paper-based deliveries, when occurring, are in themselves a logistic feat. The need for context-based adaptation of this complex information content to different actors' requirements is also challenging and need to be considered when establishing an efficient information logistic solution for provision of TP. Hence, the purpose of this paper is to provide an overview of some of the challenges and issues for establishing development and provisioning of Interactive Electronic Technical Publications (IETP[1]). Some important aspects and requirements on integration of IETP for both provider and user are also highlighted. The scope of the overview is restricted to an eMaintenance context related to military aviation.

  • 75.
    Söderholm, Peter
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Karim, Ramin
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    An enterprise risk management framework for evaluation of eMaintenance2010Ingår i: Proceedings of the 1st international workshop and congress on eMaintenance, Luleå tekniska universitet, 2010, s. 133-140Konferensbidrag (Refereegranskat)
    Abstract [en]

    Maintenance is one approach to manage risk by a reduction of the probability of failure of technical systems and/or the consequences of their failure. However, history has shown that erroneous maintenance also can lead to reduced quality, incidents and accidents with extensive losses. Today, eMaintenance promises great opportunities for a paradigm shift from a rather narrow condition-based maintenance approach with focus on technical system health to a true risk-based maintenance approach that considers organisational excellence. This is achieved by proper information logistic solutions that address the needs of all stakeholders of the maintenance process, which are possible due to new and innovative Information & Communication Technology (ICT). However, all opportunities are also linked with some threats, which seldom are highlighted in the case of eMaintenance. In this paper, a risk management framework for evaluation of eMaintenance solutions is proposed. The framework is based on a combination of international standards (e.g. ISO 31000, ISO/IEC 27000, and IEC 60300-3-14) to achieve integrated Enterprise Risk Management (ERM) and enable a linkage of eMaintenance to strategic goals of an organisation. The framework is illustrated in the context of the Swedish Rail Administration.

  • 76.
    Söderholm, Peter
    et al.
    Expert and Development Unit, Banverket.
    Karim, Ramin
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Candell, Olov
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Design of experiment and simulation for identification of significant e-maintenance services2011Ingår i: International Journal of Pedagogy, Innovation and New Technologies, ISSN 0973-1318, E-ISSN 2392-0092, Vol. 7, nr 1, s. 77-90Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The purpose of this paper is to present a methodology and a supporting toolbox that identify information-based maintenance support services using an evaluation of the services' impacts on the effectiveness of complex technical systems. A hypothetical aircraft and its support system are simulated in SIMLOX. The variables included in the model, as well as their expected effects on critical measures of system-effectiveness, were identified through interviews and studies of documents and the literature. The simulations have been planned and analysed according to established Design of Experiment (DoE) principles supported by MATLAB. Microsoft Access and Microsoft Visual Studio.NET has been used to integrate SIMLOX and MATLAB. The outcome of the study was scrutinised by both practitioners and statisticians. The methodology and its toolbox are useful for those involved in simulation work or the development of information services that support maintenance activities. The proposed systematic methodology, along with its supporting toolbox, identifies information-based services that are currently lacking when applying a Service-Oriented Architecture (SOA) approach during design and are considered valuable in identifying information-based maintenance support services within an eMaintenance solution

  • 77.
    Söderholm, Peter
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Karim, Ramin
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Candell, Olov
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Kumar, Uday
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Condition monitoring and maintenance support information services2009Ingår i: Proceedings of CM/MFPT 2009 - (CM2009): CD Proceedings of The Sixth International Conference on Condition Monitoring and Machinery Failure Prevention Technologies - CM/MFPT 2009, held 23-25 June 2009 at the Stillorgan Park Hotel, Dublin, Ireland, Longborough, Glos.: British Institute of Non-Destructive Testing and Coxmoor Publishing , 2009, s. 284-294Konferensbidrag (Refereegranskat)
    Abstract [en]

    Interaction with technological systems is an intrinsic part of daily life. The complexity of these man-made systems has reached unprecedented levels, and challenges the organizations that develop and utilize them. Simultaneously, they are often used in environments that imply very high requirements on safety, credibility, and reliability. Hence, users of complex systems need information support to access and maintain the utility and services that the system-of-interest is to provide. Examples of solutions for this are Built-in Test (BIT) and Condition Monitoring (CM) systems aimed at increased maintainability performance of technical systems. However, despite these solutions there are still drawbacks manifested by No Fault Found (NFF) and Dead-on-Arrival (DoA) events, which may erode any benefits that BIT and CM systems may provide. Hence, in spite of tremendous development of information services for complex systems, there is still a problem for users to access and understand the information. Therefore, the development of maintenance support information services need to be evolved. This paper describes a service-oriented approach to CM as support to maintenance of complex technical systems. The service-oriented CM can be integrated in an information logistics solution through the utilization of new and innovative Information & Communication Technology (ICT). The proposed approach is illustrated in the context of modern aircraft.

  • 78.
    Thaduri, Adithya
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Al-Jumaili, Mustafa
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Kour, Ravdeep
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Karim, Ramin
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Cybersecurity for eMaintenance in Railway Infrastructure: Risks and Consequences2019Ingår i: International Journal of Systems Assurance Engineering and Management, ISSN 0975-6809, E-ISSN 0976-4348, Vol. 10, nr 2, s. 149-159Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Recently, due to the advancements in the ICT (Information and Communication Technology), there has been lot of emphasis on digitization of the existing and newly developed infrastructure. In transportation infrastructure, in general, 80% of the assets are already in place and there has been tremendous push to move to the digital era. For efficient and effective design, construction, operation and maintenance of the infrastructure, due to this digitization, there is increasing research trend in data-driven decision-making algorithms that are proved to be effective because of several advantages. Since railway is the backbone of the society, the data-driven approaches will ensure the continuous operation, efficient maintenance, planning and potential future investments. The breach and leak of this potential data to the wrong hands might result in havoc, risk, trust, hazards and serious consequences. Hence, the main purpose of this paper is to stress the potential challenges, consequences, threats, vulnerabilities and risk management of data security in the railway infrastructure in context of eMaintenance. In addition, this paper also identifies the research methods to obtain and secure this data for potential possible research.

  • 79.
    Tretten, Phillip
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Karim, Ramin
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Enhancing the usability of maintenance data management systems2014Ingår i: Journal of Quality in Maintenance Engineering, ISSN 1355-2511, E-ISSN 1758-7832, Vol. 20, nr 3, s. 290-303Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Purpose – The purpose of this paper is to explore and study the aspects of usability related to eMaintenance solutions. The study aims to expand the domain of eMaintenance by increasing the usefulness of the computerized maintenance management systems (CMMS) through improved usability.Design/methodology/approach – The paper opted for an exploratory study using interviews, one expert focus group discussion, and observations.Findings – The paper provides insights on specific usability characteristics that can be adapted to eMaintenance solutions for industrial usage, e.g. aviation and process industry. The findings show that the current implementations of eMaintenance solutions in CMMS, in many cases, suffer from an insufficient level of usability. This has led to usability issues resulting in errors and mistakes. The result is a call for a more user-based focus, in which, the system needs to be easily understood, easily navigated, containing the necessary information to conduct maintenance tasks, tracking of the work conducted and who was involved, and the system needs to be compatible with other systems so that necessary information can be accessed via the CMMS.Research limitations/implications – Because of the chosen research approach, the research results may lack generalizability. Therefore, researchers are encouraged to test the proposed propositions further.Practical implications – The paper includes implications for the development of a CMMS, which could have positive effects for maintenance tasks.Originality/value – This paper fulfills an identified need to study how CMMS actually fulfill the task they are designed to do.

  • 80.
    Tretten, Phillip
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Karim, Ramin
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Project: iMain ‘Methodologies and tools for the sustainable, predictive maintenance of production equipment’2016Övrigt (Övrig (populärvetenskap, debatt, mm))
    Abstract [en]

    “iMain” is an European level research project aiming to develop a novel decision support system for predictive maintenance. To that end, a multi-layer solution integrating embedded information devices and artificial intelligence techniques for knowledge extraction and novel reliability & maintainability practices will be developed. The resulting solution will provide extended capabilities compared to those achievable with current state-of-the-art maintenance practices, increasing system lifetime of the production equipment at least 30%, energy efficiency at least 20%, maintenance cost at least 40% and availability of whole process at least 30%. As for maximizing project impact, “iMain” project is strongly committed to deployment issues, including innovation and implementation actions focused on value chains and bridging the gap from research to market. To that end, “iMain” emphasizes on the commercialization of results, taking also into account the needs of post-project monitoring of commercialization, which will be conducted after the end of the project in order to assess the achievement of the requested funding and for promoting the project as an effective innovation mechanism. As a step towards the Europe 2020 strategy, “iMain” project will thus make a contribution in terms of R&D investment, employment and resource efficiency, aiming to assist EU manufacturers, particularly SMEs, to adapt to global competitive pressures by increasing the technological base of EU manufacturing through the development and integration of the enabling technologies of the future, specifically engineering technologies for novel predictive maintenance solutions.

  • 81.
    Tretten, Phillip
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Karim, Ramin
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Kumar, Uday
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Usability-based eMaintenance for effective performance measurement2011Ingår i: MPMM 2011: Maintenance Performance Measurement & Management: Conference Proceedings / [ed] Diego Galar; Aditya Parida; Håkan Schunnesson; Uday Kumar, Luleå: Luleå tekniska universitet, 2011, s. 53-59Konferensbidrag (Refereegranskat)
    Abstract [en]

    Today’s providers of eMaintenance solutions for maintenance and support related to complex technical systems are facing increasing amounts of information flow with the increased complexity of managing data. Organizations developing and providing maintenance support solutions and services also need to improve the capability to efficiently and effectively exploit the increasing amount of design data, product data, operational data, and maintenance data during the system’s whole lifecycle. eMaintenance includes monitoring, collection, recording, and distribution of real-time system health data, maintenance-generated data, as well as, other decision and performance-support information to different types of users. To address the challenges that arise in complex information environments providers need to adapt usability-centered methodologies, technologies, and tools that enable utilization of the advantages eMaintenance solutions can give. Since humans make critical maintenance decisions based upon system performance measured by use of available data, it is necessary that the users understand the underlying data correctly in the correct context. Subsequently the amount of maintenance data is increasing constantly, thus, human factors issues need to be considered in development of eMaintenance solutions so that performance quality, productivity, and profitability are maintained. In turn this would also reduce situations where too much or incorrect information would decrement the users cognitive capabilities to make good decisions. The usability challenges faced by eMaintenance are complex and need to be taken seriously. Hence, the purpose of this paper is to explore eMaintenance design challenges based upon user issues in complex system environments. The results of this paper will present an overview of areas that need to be considered for further research within the field of eMaintenance.

  • 82.
    Tretten, Phillip
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Parida, Aditya
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Karim, Ramin
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Candell, Olov
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Guest editorial2015Ingår i: International Journal of COMADEM, ISSN 1363-7681, Vol. 18, nr 2, s. 5-6Artikel i tidskrift (Övrigt vetenskapligt)
  • 83.
    Wandt, Karina
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Karim, Ramin
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Galar, Diego
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Context adapted prognostics and diagnostics2012Ingår i: The Ninth International Conference on Condition Monitoring and Machinery Failure Prevention Technologies, 2012, Vol. 1, s. 541-550Konferensbidrag (Refereegranskat)
    Abstract [en]

    Context adaptation is an important aspect of prognostics and diagnostics as it facilitates the ability to provide relevant information to the consumers of that information. For example, eTechnologies facilitate the communication of data between systems and they assist stakeholders in different parts of an enterprise to make decisions based on the same data. However, decisions may differ, depending on individual stakeholders and specific prognostic and diagnostic processes and techniques, e.g. data fusion or data mining. The correct use of eTechnologies can improve the maintenance of an item or system, thus extending its remaining useful life. The challenge is learning how to make good use of eTechnology and ensure that the right information is provided to the right information consumer, e.g. stakeholders within various processes of an enterprise.Technical solutions in industry are often complex; they are created in heterogeneous environments and the information generated must adapt to different user contexts. Hence, context adaptation can be considered a key requirement for systems operating in heterogeneous environments. This paper considers context to be a template that describes a set of generalised characteristics of a real-world situation; the information in the template differs depending on the situation but the type of information is the same. It defines context adaption as the process of gathering information about the context template, such as structure and information type, evaluating this information and changing the observable behaviour to fit the current context

  • 84.
    Wandt, Karina
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Tretten, Phillip
    Luleå tekniska universitet, Institutionen för ekonomi, teknik och samhälle.
    Karim, Ramin
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Usability aspects of eMaintenance solutions2012Ingår 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. 77-84Konferensbidrag (Refereegranskat)
  • 85.
    Zhang, Liangwei
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Karim, Ramin
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Big Data Mining in eMaintenance: An Overview2014Ingår 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. 159-170Konferensbidrag (Refereegranskat)
    Abstract [en]

    Maintenance related data are tending to be increasingly huge involume, rapid in velocity and vast in variety. Data with thesecharacteristics bring new challenges with respect to data analysisand data mining, which requires new approaches andtechnologies. In industry, related research and applications, somecontributions have been provided to utilize Big Data technologiesfor extraction of information through pattern recognitionmechanisms via eMaintenance solutions. Today, the existingcontributions are not enabling a holistic approach for maintenancedata analysis and therefore are insufficient. However, theimmense value hidden inside the Big Data in eMaintenance isarousing more and more attention from both academia andindustry. Hence, this paper aims to explore eMaintenancesolutions for maintenance decision-making through utilization ofBig Data technologies and approaches. The paper discusses BigData mining in eMaintenance through a general manner byemploying one of the widely accepted frameworks with the nameof Cross Industry Standard Process for Data Mining (CRISPDM).In addition, the paper outlines features of maintenance dataand investigates six sub-processes (i.e. business understanding,data understanding, data preparation, modeling, evaluation anddeployment) of data mining applications defined by CRISP-DMwithin the domain of eMaintenance.

  • 86.
    Zhang, Liangwei
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Lin, Janet
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Karim, Ramin
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Adaptive Kernel Density-based Anomaly Detection for Nonlinear Systems2018Ingår i: Knowledge-Based Systems, ISSN 0950-7051, E-ISSN 1872-7409, Vol. 139, nr 1, s. 50-63Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This paper presents an unsupervised, density-based approach to anomaly detection. The purpose is to define a smooth yet effective measure of outlierness that can be used to detect anomalies in nonlinear systems. The approach assigns each sample a local outlier score indicating how much one sample deviates from others in its locality. Specifically, the local outlier score is defined as a relative measure of local density between a sample and a set of its neighboring samples. To achieve smoothness in the measure, we adopt the Gaussian kernel function. Further, to enhance its discriminating power, we use adaptive kernel width: in high-density regions, we apply wide kernel widths to smooth out the discrepancy between normal samples; in low-density regions, we use narrow kernel widths to intensify the abnormality of potentially anomalous samples. The approach is extended to an online mode with the purpose of detecting anomalies in stationary data streams. To validate the proposed approach, we compare it with several alternatives using synthetic datasets; the approach is found superior in terms of smoothness, effectiveness and robustness. A further experiment on a real-world dataset demonstrated the applicability of the proposed approach in fault detection tasks.

  • 87.
    Zhang, Liangwei
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Lin, Janet
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Karim, Ramin
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    An Angle-based Subspace Anomaly Detection Approach to High-dimensional Data: With an Application to Industrial Fault Detection2015Ingår i: Reliability Engineering & System Safety, ISSN 0951-8320, E-ISSN 1879-0836, Vol. 142, s. 482-497Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The accuracy of traditional anomaly detection techniques implemented on full-dimensional spaces degrades significantly as dimensionality increases, thereby hampering many real-world applications. This work proposes an approach to selecting meaningful feature subspace and conducting anomaly detection in the corresponding subspace projection. The aim is to maintain the detection accuracy in high-dimensional circumstances. The suggested approach assesses the angle between all pairs of two lines for one specific anomaly candidate: the first line is connected by the relevant data point and the center of its adjacent points; the other line is one of the axis-parallel lines. Those dimensions which have a relatively small angle with the first line are then chosen to constitute the axis-parallel subspace for the candidate. Next, a normalized Mahalanobis distance is introduced to measure the local outlier-ness of an object in the subspace projection. To comprehensively compare the proposed algorithm with several existing anomaly detection techniques, we constructed artificial datasets with various high-dimensional settings and found the algorithm displayed superior accuracy. A further experiment on an industrial dataset demonstrated the applicability of the proposed algorithm in fault detection tasks and highlighted another of its merits, namely, to provide preliminary interpretation of abnormality through feature ordering in relevant subspaces.

  • 88.
    Zhang, Liangwei
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Lin, Janet
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Karim, Ramin
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Sliding Window-based Fault Detection from High-dimensional Data Streams2017Ingår i: IEEE Transactions on Systems, Man & Cybernetics. Systems, ISSN 2168-2216, Vol. 47, nr 2, s. 289-303, artikel-id 7509594Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    High-dimensional data streams are becoming increasingly ubiquitous in industrial systems. Efficient detection of system faults from these data can ensure the reliability and safety of the system. The difficulties brought about by high dimensionality and data streams are mainly the ``curse of dimensionality'' and concept drifting, and one current challenge is to simultaneously address them. To this purpose, this paper presents an approach to fault detection from nonstationary high-dimensional data streams. An angle-based subspace anomaly detection approach is proposed to detect low-dimensional subspace faults from high-dimensional datasets. Specifically, it selects fault-relevant subspaces by evaluating vectorial angles and computes the local outlier-ness of an object in its subspace projection. Based on the sliding window strategy, the approach is further extended to an online mode that can continuously monitor system states. To validate the proposed algorithm, we compared it with the local outlier factor-based approaches on artificial datasets and found the algorithm displayed superior accuracy. The results of the experiment demonstrated the efficacy of the proposed algorithm. They also indicated that the algorithm has the ability to discriminate low-dimensional subspace faults from normal samples in high-dimensional spaces and can be adaptive to the time-varying behavior of the monitored system. The online subspace learning algorithm for fault detection would be the main contribution of this paper.

  • 89.
    Kumar, Uday (Redaktör)
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Karim, Ramin (Redaktör)
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Parida, Aditya (Redaktör)
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Tretten, Phillip (Redaktör)
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Proceedings of the 3rd international workshop and congress on eMaintenance: June 17-18 Luleå, Sweden : eMaintenance, Trends in technologies & methodologies, challenges, possibilites and applications2014Rapport (Refereegranskat)
    Abstract [en]

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

12 51 - 89 av 89
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