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  • 601.
    Klefsjö, Bengt
    et al.
    Luleå tekniska universitet, Institutionen för ekonomi, teknik och samhälle, Industriell Ekonomi.
    Söderholm, Peter
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    TTT-plotting: an efficient way to analyse reliability data2006Ingår i: Proceedings of the First International Conference on Maintenance Engineering, 2006, s. 846-854Konferensbidrag (Refereegranskat)
    Abstract [en]

    The TTT-plot based on failure times from non-repairable units and its theoretical counterpart, the scaled TTT-transform, based on the corresponding life distribution, was presented thirty years ago as a tool for model identification purposes. Since then a number of different applications of TTT-plotting have been presented. Among these are analysis of different aging properties, optimization of age replacement problems and TTT-plotting as a source for creating and studying test statistics. Furthermore, different generalizations have been presented. Among these are applications to repairable units and use of censored failure times. This paper gives an overview of TTT-plotting and a number of practical and theoretical applications with a wide range of references for further reading.

  • 602.
    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 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.

  • 603.
    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)
  • 604.
    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.

  • 605.
    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.

  • 606.
    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.

  • 607.
    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.

  • 608.
    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.
    Predictive model for multistage cyber-attack simulation2020Ingår i: International Journal of Systems Assurance Engineering and Management, ISSN 0975-6809, E-ISSN 0976-4348Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Adoption of information and communication technologies (ICT) in railway has improved the reliability, maintainability, operational efficiency, capacity as well as the comfort of passengers. This adoption introduces new vulnerabilities and entry points for hackers to launch attacks. Advanced cybersecurity threats with automated capabilities are increasing in such sectors as finance, health, grid, retail, government, telecommunications, transportation, etc. These cyber threats are also increasing in railways and, therefore, it needs for cybersecurity measures to predict, detect and respond these threats. The cyber kill chain (CKC) model is a widely used model to detect cyber-attacks and it consists of seven stages/chains; breaking the chain at an early stage will help the defender stop the adversary’s malicious actions. Due to lack of real cybersecurity data, this research simulates cyber-attacks to calculate the attack penetration probabilities at each stage of the cyber kill chain model. The objective of this research is to predict cyber-attack penetrations by implementing various security controls using modeling and simulation. This research is an extension of developed railway defender kill chain which provides security controls at each stage of CKC for railway organizations to minimize the risk of cyber threats.

  • 609.
    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.

  • 610.
    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 to Predict and Detect Cyber-Attacks2020Ingår i: Journal of Cyber Security and Mobility, ISSN 2245-1439, E-ISSN 2245-4578, Vol. 9, nr 1, s. 47-90Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Most organizations focus on intrusion prevention technologies, with lessemphasis on prediction and detection. This research looks at prediction anddetection in the railway industry. It uses an extended cyber kill chain (CKC)model and an industrial control system (ICS) cyber kill chain for detectionand proposes predictive technologies that will help railway organizationspredict and recover from cyber-attacks. The extended CKC model consistsof both internal and external cyber kill chain; breaking the chain at anearly stage will help the defender stop the adversary’s malicious actions.This research incorporates an OSA (open system architecture) for railwayswith the railway cybersecurity OSA-CBM (open system architecture forcondition-based maintenance) architecture. The railway cybersecurity OSA-CBM architecture consists of eight layers; cybersecurity information movesfrom the initial level of data acquisition to data processing, data analysis, inci-dent detection, incident assessment, incident prognostics, decision support,and visualization.The main objective of the research is to predict, prevent, detect, andrespond to cyber-attacks early in the CKC by using defensive controls calledthe Railway Defender Kill Chain (RDKC).The contributions of the research are as follows. First, it adapts and mod-ifies the railway cybersecurity OSA-CBM architecture for railways. Second,it adapts the cyber kill chain model for the railway. Third, it introduces theRailway Defender Kill Chain. Fourth, it presents examples of cyber-attackscenarios in the railway system.

  • 611.
    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.

  • 612.
    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.

  • 613.
    Kristiansen, Pontus
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Postnikov, Roman
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Tillståndsövervakning av rullningslager med hjälp av E-näsa2018Självständigt arbete på grundnivå (yrkesexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    I dagsläget finns det ingen standardiserad metod för att mäta en enhets tillstånd medhjälp av dofter. Vid tillståndsövervakning av rullningslager är vibrationsmätning denmest dominanta metoden. I samband med vibrationsmätning används i vissa falltemperaturövervakning för att få en bättre insikt på rullningslagrets tillstånd. I det härarbetet undersöks de om en elektronisk näsa kan avgöra ett rullningslagers tillstånd.Innan några mätningar påbörjas monterades en elektronisk näsa ihop i ett hölje sombestår av ett kretskort, metalloxid-sensorer och en fläkt för att styra dofter med ettkonstant flöde mot sensorerna. Den elektroniska näsan styrs av en Arduino Nanomikrokontroller. Utöver e-näsan sättes en enhet ihop tillhörande två temperaturgivareoch en luftfuktighetsgivare som styrs av en Arduino UNO. Enhetens syfte är att kunnakontrollera de rådande förhållandena vid mätningar och för att leta någon form avkorrelation mot e-näsan vid eventuella utslag. Förstörande prover av kullager utfördesför att se om e-näsan reagerar innan ett lagerhaveri. Testerna gjordes i en öppen samtsluten miljö och tre stycken olika oljor används för att smörja lagret. Detta för att seom e-näsan reagerar olika beroende på vilken olja som används. En undersökningutförs ifall den elektroniska näsan kan separera på de tre oljorna som används ilagertesterna. För att utvärdera mätresultaten används Excel och Minitab, därprincipalkomponentanalyser genomförs på all mätdata. Efter att alla lagerprover harverkställts utfördes en uppföljning av rullningslagrena för att studera deras tillstånd,detta genom ett optiskt mikroskop.Det framgår i rapporten att med hjälp av analysmetoden PCA syns det att denelektroniska näsan kunde skilja på hydraulolja, motorolja och växellådsolja. Utslag iPCA för de olika mätserierna blev inte identiska men det blev tydligaklusterindelningar hos samtliga mätserier. Genomförd studie visade att med delagerhaveri samt temperaturer går det inte att avgöra ett kullagers tillstånd med hjälpav en elektronisk näsa. Eftersom att de specifika gas-sensorerna som användes till enäsaninte gav någon form av utslag vid mätningarna. Den elektroniska näsanreagerade däremot vid totalhaveri av kullager, vilket är för sent i ett förebyggandeunderhållsperspektiv. Detta medförde att den elektroniska näsan inte kan användas förtillståndsövervakning av det specifika kullagret som användes vid denna studie.

  • 614.
    Kumar, Dhananjay
    et al.
    Luleå tekniska universitet.
    Kumar, Uday
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Reliability analysis of critical components of Load-Haul-Dump-Machines1992Rapport (Övrigt vetenskapligt)
  • 615.
    Kumar, Rajesh
    et al.
    Luleå tekniska universitet.
    Kumar, Uday
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    A conceptual framework for the development of a service delivery strategy for industrial systems and products2004Ingår i: The journal of business & industrial marketing, ISSN 0885-8624, E-ISSN 2052-1189, Vol. 19, nr 5, s. 310-319Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Service and product support are increasingly critical elements in the achievement of customer satisfaction and winning new markets. The success of a product support strategy depends on how effectively these services are delivered. The focus of this paper is on performance enhancement through the use of service delivery strategies; critical factors in the marketing of product support and service-related contracts that in turn, foster customer satisfaction, based on industrial systems in a multinational environment Considered in the framework are product design characteristics such as reliability, maintainability, customer's organizational culture and geographical location, for functional as well as conventional products. The paper advocates an increased focus on support to customers within the framework, introduces a modified service gap model and suggests an approach that reduces any gap between expected and required services. An evaluation of service delivery performance is emphasized.

  • 616.
    Kumar, Rajesh
    et al.
    Luleå University of Technology.
    Kumar, Uday
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Service delivery strategy: trends in mining industries2004Ingår i: International Journal of Mining, Reclamation and Environment, ISSN 1748-0930, E-ISSN 1748-0949, Vol. 18, nr 4, s. 299-307Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Mine operators are increasingly outsourcing non-core business processes. Often, the maintenace issue is treated as a non-core business by the mining industry. In today's business environment, many industrial operators/users are interested in buying performance rather than physical products. It is a common practice for an original equipment manufacturer (OEM)/supplier of a product to own, operate, maintain, and support his product. Product performance in general is defined in a negotiated agreement. Even in a conventionl product scenario a user/mine operator often prefers to outsource maintenance to OEMs or contractors in order to focus on core business goals. This paper reviews the recent trends in delivery of product support within segments of the mining industry. In this paper, we advocate the adoption of 'solution-selling' and 'total care solutions' into the mining industry. There appears to be a strong likehood that these concepts can benefit the mining industry. Solution selling and total care solutions are seen as applicable to the mining industry because the product/equipment utilised in this industry are specialised and often expensive. The strategies addressed in this paper support a mine operator's option to buy process instead of physical products, and the increasing demand for a total solution.

  • 617.
    Kumar, Rajesh
    et al.
    University of Stavanger.
    Markeset, Tore
    University of Stavanger.
    Kumar, Uday
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Implementation and execution of industrial service strategy: a case study from the oil and gas industry2006Ingår i: Journal of Quality in Maintenance Engineering, ISSN 1355-2511, E-ISSN 1758-7832, Vol. 12, nr 2, s. 105-117Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Purpose - The purpose of the paper is to discuss the complex issues, obstacles and factors that can have a significant role and influence on the implementation and execution of a performance-based industrial service strategy. Design/methodology/approach - A case study has been performed the oil and gas industry which maps the issues, challenges and opportunities in the process of implementing and executing a performance-based service strategy. Findings - The study identifies differences in practice with respect to conventional as compared to performance-based contracts. Furthermore, performance factors (i.e. cost drivers, performance killers and critical success factors) of the service strategy implementation and execution process are discussed in relation to the oil and gas industry in the North Sea. A performance-based service strategy needs to be upgraded, modified and customized based on performance measurements, as well as needs, wants and preferences of the involved parties during the contract period. Practical implications - The findings and discussions will help service strategy developers, implementers and executors to recognize the importance of a focused service strategy development process for industrial services. Moreover, the paper will guide developers, implementers and executors to decide about factors that need to be considered. Originality/value - The framework discussed can be used to develop a performance-based service strategy. The results of the research will ease the process of understanding and defining the implementation and execution process of a strategy by presenting the possible performance factors in advance.

  • 618.
    Kumar, Rajesh
    et al.
    Luleå University of Technology.
    Markeset, Tore
    Stavanger University College.
    Kumar, Uday
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Maintenance of machinery: negotiating service contracts in business-to-business marketing2004Ingår i: International Journal of Service Industry Management, ISSN 0956-4233, E-ISSN 1758-6704, Vol. 15, nr 3/4, s. 400-413Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    As industrial products are becoming more advanced and complex, the role of supporting services needed to exploit a product's function to an agreeable performance is becoming increasingly important To achieve the best performance, industrial customers are entering into service contracts with the original equipment manufacturers (OEM) or independent service providers. This, in turn essentially involves service contract negotiation between OEM/service provider and the client If such contracts are not negotiated carefully, it may lead to conflict and poor system Performance. To achieve a win-win situation for both parties, aspects such as what services to deliver, who is to deliver them, how they are to be delivered and received, and at which performance level, need to be considered in the negotiation process and agreed upon by both the provider and the client. A conceptual framework has been developed for service delivery negotiation process based on review of literature and analysis of results from a survey conducted to study the existing approaches being practiced by the industrial organizations to negotiate a service contract.

  • 619.
    Kumar, Rupesh
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Barabady, Javad
    Center for Safe Operation in HIGH North, University of Tromsø.
    Markeset, Tore I.
    Center for Safe Operation in HIGH North, University of Tromsø.
    Kumar, Uday
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Improving maintainability in extreme cold climatic conditions2012Ingår i: International Journal of Pedagogy, Innovation and New Technologies, ISSN 0973-1318, E-ISSN 2392-0092, Vol. 8, nr 5, s. 563-572Artikel i tidskrift (Refereegranskat)
    Abstract [en]

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

  • 620.
    Kumar, Rupesh
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Barabady, Javad
    Markeset, Tore
    Tromsø University.
    Kumar, Uday
    Improvement of performance of oil and gas production facilities in arctic regions by applying human factors/ergonomic principles at the design phase2009Ingår i: Proceedings of the 20th International Conference on Port and Ocean Engineering under Arctic Conditions: June 9-12, 2009, Luleå, Sweden, 2009Konferensbidrag (Refereegranskat)
    Abstract [en]

    The system with a low level of reliability of being deployed in a cold climate often needs special and additional focus on maintainability characteristics in order to achieve the higher level of productivity, system availability and safety. Therefore, the maintainability issue is critical for the successful and effective operation of oil and gas installations in the Arctic environment as the working conditions are made very difficult by low temperature, ice, short period of daylight and lack of support facilities. Furthermore, the maintenance tasks or maintainability in the Arctic region is heavily influenced by the design of the task and the design of the equipment being maintained. The risk of human error in the Arctic environment is very high and about 80% of offshore accidents are caused by humans, with 64% occurring during operations. Morover, human factors/ergonomics is now recognized as a major contributor to operational safety, loss prevention and optimizing system performance in the oil and gas industries. Therefore, the study of human factor and reliability is essential to ensure the safe and reliable operation of industrial plant and systems which involve human operators. Human factors' integration aims to 'design-in' the humans into plant and system design, taking account of their capabilities and limitations. This can lead to significant savings through appropriate manning levels, maintainable plant, reduced rework and user-friendly facilities and systems.The objective of this paper is to explore potential risk factors especially in Arctic conditions with a view to how human factors/ergonomic principles can help to reduce risk factors and increase maintainability of the oil and gas industry. In this paper, the starting point is the offshore oil and gas industry, but the methodology and discussion are to a large extent general and could also be applied in the other industries.

  • 621. Kumar, Rupesh
    et al.
    Kumar, Uday
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Service strategy for mining system2002Ingår i: MTM - 2002 Proceedings: International Seminar on Mining, Technology, and Management for Business Excellence, New Delhi, November 2002, 2002Konferensbidrag (Refereegranskat)
  • 622.
    Kumar, Rupesh
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Markeset, Tore
    University of Stavanger.
    Barabady, Javad
    Tromsø University.
    Kumar, Uday
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Ergonomic issues at a railway maintenance workshop2011Ingår i: Proceedings of the 24th International Congress on Condition Monitoring and Diagnosis Engineering Management: COMADEM 2011 / [ed] Maneesh Singh; Raj B.K.N. Rao; J.P. Liyanage, COMADEM International, 2011, s. 1583-1587Konferensbidrag (Refereegranskat)
    Abstract [en]

    Research on human factors related to railway operation and maintenance has, to an extent, been the neglected branch of transport ergonomics. Despite the numerous reports of ergonomics programs in a variety of industries, no examples of implementing ergonomics interventions in the railway vehicle maintenance workshop have been reported.In this study, a maintenance process at a railway workshop was studied and analyzed with special reference to working posture and maintenance repair time. The working postures of two maintenance personnel were obtained and analyzed using OWAS (Ovako Working Posture Analysis System). From the results, it was clearly indicated that poor working posture was a frequent occurrence during the maintenance activities. It can be concluded that the introduction and implementation of ergonomics principles at the railway maintenance workshop must be considered in order to reduce the poor working postures, maintenance repair time and to improve maintainability and productivity.

  • 623.
    Kumar, Rupesh
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Theorell, Töres
    Karolinska Institutet.
    Markeset, Tore
    Centre for Industrial Asset Management, University of Stavanger, School of Science and Technology, Stavanger University College, Tromsø University, Center for Safe Operation in HIGH North, University of Tromsø.
    Comparing Psychosocial Factors Associated with Job Stress Among Administrative Staff and Cleaners2016Ingår i: Advances in Physical Ergonomics and Human Factors: Proceedings of the AHFE 2016 International Conference on Physical Ergonomics and Human Factors, July 27-31, 2016, Walt Disney World®, Florida, USA / [ed] Ravindra Goonetilleke; Waldemar Karwowski, London: Encyclopedia of Global Archaeology/Springer Verlag, 2016, s. 1013-1022Konferensbidrag (Refereegranskat)
    Abstract [en]

    In this study the Swedish version of the Demand—Decision Latitude—Social support model was used. A total of 40 administrative staff and 40 cleaners participated. Demands and decision latitude scores were significantly higher in the administrative staff than in the cleaners. Social support scores were not significantly different between the administrative group and the group of cleaners. Psychological demands and skill discretion differed between the two working groups. The administrative staff’s perception of higher work demand and better decision latitude may be based on their belief that they possess appropriate education, general knowledge and detailed information about their work. Both groups had similar social support scores; it may be that members of both groups felt that they work as a group or team where their proximity fostered this perception of group social support

  • 624. Kumar, Rupesh
    et al.
    Wijaya, Andi
    Barabady, Javad
    Tromsø University.
    Markeset, Tore
    University of Stavanger.
    Kumar, Uday
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Ergonomic and maintainability design issues in mining2009Konferensbidrag (Refereegranskat)
    Abstract [en]

    Due to confined space and poor illumination in the mine the maintenance activities are difficult to perform which in turn leads to increased down time, cost and injuries. This also influences the productivity of maintenance personnel owing to stresses generated due to increased psychological and physiological demand on them. However, the industry has paid much less attention to the design of the mining machine in initial phase itself with respect to maintainability parameters leading to low productivity, increased maintenance time and increased likelihood of accidents during maintenance and operation of such equipment. The objective of the paper is to present ergonomics factors such as; anthropometery, human sensory, physiological and psychological application in relation to maintainability design issues in mining in order to reduce occupational risk factors and improved maintainability of the mining equipments leading to increased productivity.

  • 625.
    Kumar, Saurabh
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    A study of the rail degradation process to predict rail breaks2006Licentiatavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Rail infrastructure is a large and costly investment, and has a long life. To realize the benefits from this investment, effective maintenance is required. Railways are one of the prime modes of transportation in many countries and as they are closely associated with passenger and cargo transportation, they own high risk in terms of potential loss of human life and damage/destruction of assets. New technologies and stringent safety standards are constantly being introduced, but accidents still occur. There will always be some risk associated with derailments and collisions, but it can be reduced by elimination of the root causes by means of an effective maintenance strategy to govern optimization of inspection, lubrication and grinding frequency and/or improvement in skill and efficiency. A detailed study of the defects which emerge both in the rolling stock and the rail infrastructure is essential to identify the correct maintenance strategy. Detection and rectification of rail defects/degradations are major issues for all rail players around the world. Some of the rail degradations include worn out rails, weld problems, internal defects, corrugations and rolling contact fatigue (RCF) initiated problems such as surface cracks, head checks, squats, spalling and shelling. If undetected and/or untreated, these defects can lead to rail breaks and derailments. Efficient maintenance strategies can reduce potential risk of rail breaks and derailments. A potential risk is the risk which accumulates in the form of rail degradation over a period of time. In spite of continuous efforts made by all rail infrastructure operators around the world to reduce costs, a substantial proportion of railway budget is spent on rail maintenance. It is understood that the consequential costs due to derailment reduces with increase in inspection, lubrication, grinding and replacement costs. The challenge is to find a balance between the maintenance costs which consists of inspection, lubrication and grinding costs, and consequential costs due to derailments. The consequences of derailment in terms of loss of human life, damage/destruction of assets and loss of company trust and reputation justify maintaining stringent safety standards, which require massive rail maintenance investments in order to be met. Reduction in maintenance investments may increase the rate of rail degradation, which may increase the risk of derailments. The aim is to develop an approach to predict rail failures, which will help to optimize maintenance activities (inspection, grinding, rectification/replacement and/or welding). Generally, there is a trade-off between maintenance investment and the risk involved in rail degradation in order to develop a rail maintenance procedure. Failure prediction of rail sections undergoing degradation will help to estimate the risk of derailment. Thus, prediction of the rail failure rate is a requirement for the development of an effective rail maintenance procedure. Different types of rail degradation processes leading to various rail defects have been studied. The performed literature studies indicate a need for better prediction of rail failure over a period of time based on the factors influencing rail degradation. The maintenance strategy followed by the Swedish National Rail Administration (Banverket), Sweden's rail infrastructure operator, is described and the issues related to rail degradation and maintenance are outlined for further research in this area. Rail failure data has been extracted from different Banverket's databases, classified according to a classification framework developed and analyzed over a period of time based on Million Gross Tonnes (MGT) of traffic using Weibull distribution. During the process of data evaluation and analysis, a method of extracting useful information from incomplete data has been identified.

  • 626.
    Kumar, Saurabh
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Reliability analysis and cost modeling of degrading systems2008Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Degradation is an on-going process in systems, equipments and components subjected to various stresses and adverse operating conditions. The factors influencing the degradation process may adversely affect the system or component performance. A study of these factors will provide a basis for making correct decisions concerning corrective and preventive measures. Such a study is also useful for reliability analysis of the degrading systems/components for making maintenance decisions or for initiating measures for changes in the design. Many times it is not possible to implement design changes due to complexities and cost considerations, as in the case of railway infrastructures, etc. In such situations operational reliability is assured through effective maintenance actions. Knowledge of the technical condition of components is important to achieve the optimal maintenance policy in order to minimize the total system risk. A methodology for rail defect prioritization and risk assessment is developed to support the decision- making process during the effective scheduling of the inspection frequency based on the type of defect and its risk of developing into a rail break. The present research work also demonstrates an application of reliability analysis to improve system reliability based on design changes. This has been illustrated with an example from a manufacturing industry. The objective is achieved using cost-benefit analysis in combination with failure data and root cause analysis. The analysis of failure data with the different cost elements involved in the operation and maintenance of the complex systems is presented as a basis for choosing between alternative designs. Furthermore, an optimization model has been developed to estimate the optimum inspection frequency required at the minimum maintenance cost based on the technical condition of the component. The model has been validated by a case study of an offshore oil and gas platform. The consequences of not choosing the right distribution have also been discussed in the thesis. The concept of the virtual failure state has been introduced to estimate the failure distribution of highly critical components. The factors influencing the degradation process have been identified and studied in detail. A framework for classification of rail failure data has also been developed for rail life estimation using reliability analysis. In short, the thesis discusses the application of reliability analysis and cost modeling techniques to support the decision-making process in operation and maintenance activities and demonstrates its usefulness in real life.

  • 627.
    Kumar, Saurabh
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Study of rail breaks: associated risks and maintenance strategies2006Rapport (Övrigt vetenskapligt)
    Abstract [en]

    Railways are large infrastructures and are the prime mode of transportation in many countries. As it is closely associated with passenger and cargo transportation, it owns high risk in terms of human lives and cost of assets. New technologies and better safety standards are constantly introduced but still accidents do occur. There will always be some risk associated with derailments and collisions but it can be reduced by elimination of the root causes. These causes necessitate an effective maintenance strategy to govern optimization of inspection frequency and/or improvement in skill and efficiency. A detailed study of the defects which emerge both on the rolling stock and rail infrastructure is essential to frame out the correct maintenance strategy. Detection and rectification of rail defects are major issues for all rail players around the world. Some of the defects include worn out rails, weld problems, internal defects, corrugations and rolling contact fatigue (RCF) initiated problems such as surface cracks, head checks, squats, spalling and shelling. If undetected and/or untreated these defects can lead to rail breaks and derailments. There are challenges to the infrastructure maintenance people to perform effective inspection and cost effective rectification decisions. If these issues are addressed properly, inspection and rectification decisions can reduce potential risk of rail breaks and derailments. In-spite of continuous efforts made by all rail operators around the world to reduce costs, a substantial amount of railway budget is spent on inspection and maintenance of rails. It is understood that the consequential cost due to derailment reduces with increase in inspection, lubrication and grinding costs. The challenge is to reduce the maintenance cost which consists of inspection, lubrication and grinding costs and at the same time prevent a rise in consequential cost due to derailment. Risk evaluation has become an important parameter for the management to decide a better and cost effective solution that could meet the budgetary constraints regarding renewal, replacement and inspection frequency of rails and wheels. Thus, before development of any model or any empirical relationship associated with risk, familiarity with risk management tools is required. This study focuses on building up a basic knowledge required for establishing such a relationship. The aim is to reduce costs and risks related to rail operation by effective decisions related to rail inspection, grinding, lubrications, rectifications and rail replacements. Different types of rail defects and degradation processes have been studied. From the literature survey and studies done by the author, it is interpreted that there is a need for better prediction of rail defects over a period of time based on operating conditions and maintenance strategies. The issues and challenges related to rail maintenance are outlined for further research in this area. The maintenance strategy followed by Banverket is also described.

  • 628. Kumar, Saurabh
    et al.
    Chattopadhyay, G.
    Kumar, Uday
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Kumar, K.
    Application of design changes for improvement of system reliability: a case study2005Ingår i: Proceedings of 18th International Congress on Condition Monitoring and Diagnostic Engineering Management: Comadem - 2005, Cranfield: Cranfield University Press , 2005, s. 83-92Konferensbidrag (Refereegranskat)
  • 629. Kumar, Saurabh
    et al.
    Chattopadhyay, Gopi
    Queensland University of Technology School of Engineering Systems.
    Kumar, Uday
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Reliability improvement through alternative designs: a case study2007Ingår i: Reliability Engineering & System Safety, ISSN 0951-8320, E-ISSN 1879-0836, Vol. 92, nr 7, s. 983-991Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In today's competitive world, reliability of equipment is extremely important to maintain quality and delivery deadlines. This is achieved by using proper maintenance and design changes for unreliable subsystems and components of a complex system. It is significant to develop a strategy for maintenance, replacement and design changes related to those subsystems and components. An analysis of down time along with causes is essential to identify the unreliable components and subsystems. This paper presents an analysis of failure data of solenoid coils of automatic internal grinding machine used in a bearing manufacturing plant. It analyses various replacement and change of design options such as introduction of pneumatic system in place of electromagnetic solenoids for improvement of reliability of the plunger movement mechanism.

  • 630. Kumar, Saurabh
    et al.
    Dandotiya, Rajiv
    Kumar, Rajesh
    Aker Kvaerner, Stavanger.
    Kumar, Uday
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Inspection frequency optimization model for degrading flowlines on an offshore platform2008Ingår i: International Journal of Reliability, Quality and Safety Engineering (IJRQSE), ISSN 0218-5393, Vol. 15, nr 2, s. 167-180Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Many offshore oil and gas installations in the North Sea are approaching the end of their designed lifetimes. Technological improvements and higher oil prices have developed favorable conditions for more oil recovery from these existing installations. However, in most cases, an extended oil production period does not justify investment in new installations. Therefore cost-effective maintenance of the existing platform infrastructure is becoming very important. In this paper, an inspection frequency optimization model has been developed which can be used effectively by the inspection and maintenance personnel in the industry to estimate the number of inspections/optimum preventive maintenance time required for a degrading component at any age or interval in its lifecycle at a minimum total maintenance cost. The model can help in planning inspections and maintenance intervals for different components of the platform infrastructure. The model has been validated by a case study performed on flowlines installed on the top side of an offshore oil and gas platform in the North Sea. Reliability analysis has been carried out to arrive at the best inspection frequency for the flowline segments under study

  • 631. Kumar, Saurabh
    et al.
    Espling, Ulla
    Kumar, Uday
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    A holistic procedure for rail maintenance in Sweden2008Ingår i: Proceedings of the Institution of mechanical engineers. Part F, journal of rail and rapid transit, ISSN 0954-4097, E-ISSN 2041-3017, Vol. 222, nr 4, s. 331-344Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The paper discusses a procedure for systematic and holistic (considering most of the factors influencing the rail degradation process) analysis and prediction of rail failures so that rail maintenance can be performed effectively. The current rail maintenance and reporting procedure followed by Banverket (Swedish National Rail Administration) for the Swedish Iron Ore Line is also described. The paper will also discuss on the improvement areas in Banverket's database management system highlighting what to measure and record and the reason behind it.This paper will help the infrastructure managers to better understand the existing rail maintenance procedure, and the improvements which can be incorporated in the existing procedure to make it more effective.

  • 632. Kumar, Saurabh
    et al.
    Gupta, Suprakash
    Ghodrati, Behzad
    Kumar, Uday
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    An approach for risk assessment of rail defects2010Ingår i: International Journal of Reliability, Quality and Safety Engineering (IJRQSE), ISSN 0218-5393, Vol. 17, nr 4, s. 291-311Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Rail defects appear in a greater variety and frequency due to higher axle loads and increasing traffic density in passenger and freight trains. Many of these rail defects, if left undetected, can develop into rail breaks, which may lead to train derailments. Reduction in the number of such catastrophic events requires huge investments on inspection and maintenance activities. Therefore proper maintenance planning and risk assessment is required to reduce the rail maintenance cost without compromising safety. In this paper, an approach has been developed for risk assessment of rail defects to support the decision-making process during scheduling of rail inspection and grinding frequency, based on the type of defect and its risk of occurring and developing into a rail break. The approach will help in increasing the safety of passengers and rolling stock as well as reducing the overall rail maintenance cost, as it helps in making effective decisions related to inspection frequency (i.e. resource allocation according to the need). The approach is presented with the aid of a case study from the Swedish National Rail Administration (Banverket). Both, quantitative and qualitative analysis technique has been used in this paper to assess the risk of occurrence of a rail defect and its development into a rail break.

  • 633. Kumar, Saurabh
    et al.
    Kumar, Uday
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Chattopadhyay, G.
    Queensland University.
    Reddy, V.
    Queensland University.
    Issues and challenges with logistics of rail maintenance2006Ingår i: Proceedings of Abstracts and Papers of The Second International Intelligent Logistics Systems Conference 2006 / [ed] Erhan Kozan, Australian Society for Operations Research , 2006, s. 16.1-16.9Konferensbidrag (Refereegranskat)
    Abstract [en]

    Detection and rectification of rail defects are major issues for all rail players around the world. Some of the defects include worn out rails, weld problems, internal defects, corrugations and rolling contact fatigue (RCF) intiated problems such as surface cracks, head checks, squats spalling and shelling. There are challenges to the infrastructure maintenance people with logistics for effective inspection and cost effective recitification decisions. If these issues are addressed properly then inspection and rectification decisions can reduce potential risk of rail breaks and derailments. Inspite of continous efforts by all rail operators around the world to reduce costs, a substantial amount of railway budget is spent on inspection and maintenance of rails. These costs are further increased by inaccurate logistics decisions related to maintenance and inspection personnel, equipment and planning. This paper addresses the issues and challenges related to logistics of rail maintenance with an aim to reduce costs and risk related to rail operations. 

  • 634.
    Kumar, Uday
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Availability studies of load-haul-dump machines1989Ingår i: Application of computers and operations research in the mineral industry: [proceedings of the 21. International Symposium on the Application of Computers and Operations Research in the Mineral Industry held in LasVegas, NV, USA, on February 27 to March 2, 1989] / [ed] Alfred Weiss, Society for Mining, Metalurgy and Exploration, 1989, s. 323-335Konferensbidrag (Refereegranskat)
    Abstract [en]

    This paper presents details of an availability study for a fleet of diesel engine operated load-haul-dump (LHD) machines used in a Swedish mine. The LHD machines have been considered as a system comprised of many subsystems like engine, brake, trnsmission, etc., in series. The concepts of maintainability are also discussed. The need for exploring the data for the presence of any structure, which is very common in repairable system data sets, is emphasized with suitable examples. Simple graphical techniques are used for verifying the independent and identically distributed (IID) assumption for the data set. The error introduced due to the use of the exponential distribution in place of more appropriate distributions in estimation of availability and reliability characteristics is analysed.

  • 635.
    Kumar, Uday
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Basic prerequisities for the development of optimal maintenance policies for the mines1989Rapport (Övrigt vetenskapligt)
  • 636.
    Kumar, Uday
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Collaborative and intelligent mine operation and maintenance2009Konferensbidrag (Refereegranskat)
    Abstract [en]

    With increasing scales of automation, and integration of various mining es and unit operations to replace humans with machines at all levels in mining operation, the issue of effective operation and maintenance of such systems have become very critical for the economic viability and competitiveness of mining business. Since such autonomous systems are expected to perform round the clock, the importance of system characteristics such as availability, reliability, flexibility and controllability are of prime importance. A closer look at such systems indicates that data collection, analysis and information flow are essential prerequisites for the competitiveness and cost-effectiveness of such systems. If these prerequisites are not optimal, it is almost impossible to make correct decisions under dynamic conditions. To facilitate dynamic decision-making in operation and maintenance of multiple complex industrial systems, Information and Communication Technologies (ICT) are being implemented by the industries. These efforts enable the provision of appropriate decision-support to various stakeholders (such as, production managers, suppliers, maintenance managers, experts, purchasing organizations and customers) round the clock, seven days a week (24-7). The paper discusses ways and means to convert data into decision and presents CIOM 24/7 approach (Collaborative Intelligent Operation and Maintenance ) being developed at Luleå University for possible implementation in mining and other industries to meet the challenges involved in autonomous or semiautonomous operations.

  • 637.
    Kumar, Uday
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Design and development of service and maintenance concepts for mechanized and automatic mining systems2001Ingår i: Regional APCOM 2001: Symposium on Computer Applications in the Mineral Industries : proceedings of the 4th Regional Symposium on Computer Applications in the Minerals Industries, Tampere, Finland, 3-5 September 2001 / [ed] Pekka Eloranta; Pekka Särkkä, espoo: Helsinki University of Technology , 2001, s. 11-22Konferensbidrag (Refereegranskat)
  • 638.
    Kumar, Uday
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Development and implementation of maintenance performance measurement system: issues and challenges2006Ingår i: Engineering Asset Management: Proceedings of the First World Congress on Engineering Asset Management (WCEAM), Encyclopedia of Global Archaeology/Springer Verlag, 2006, s. 738-743Konferensbidrag (Refereegranskat)
    Abstract [en]

    The cost of maintenance and its influence on the total system effectiveness is too great for asset managers to ignore. The modern days asset managers need to know the relationship between the outputs from the investments in the maintenance in terms of total contribution to the business goal and the inputs to maintenance processes. In addition, without any formal measures of performance, it is difficult to plan control and improve the maintenance process. The discussion in the paper is based on some of the R &D projects being pursued at the Division of Operation and Maintenance Engineering at Luleå University of Technology, Luleå in close cooperation with infrastructure owners and asset managers in Sweden. This paper will discuss the issues and challenges associated with development, implementation of maintenance performance system and maintenance performance indicators for effective management of infrastructure and industrial assets.

  • 639.
    Kumar, Uday
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Development of maintenance policies for mines: a statistical approach1990Rapport (Övrigt vetenskapligt)
  • 640.
    Kumar, Uday
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    LCC analysis for civil infrastructure: a cradle to grave approach2012Konferensbidrag (Refereegranskat)
    Abstract [en]

    The LCC analysis is an engineering and economical optimization technique where the main goal is to identify and choose alternative that generates the highest revenue over lifetime or in other words generates the lower life cycle cost. LCC techniques have successfully been applied in many other capital-intensive industries to make optimal decision regarding investment in capital equipment. Furthermore since many underground and other rock structures remain in service for years, it is important to understand the need of maintenance for such structures. LCC analysis provides basis for decision making such as whether to design a structure that does not need any maintenance throughout its life time. Alternatively if a maintenance free structure is not possible due to the lack of knowledge of lack of technology, material etc or high cots then we select the alternative design for maintenance so that such structures can be inspected, maintained and operated easily and in a cost effective way. The maintenance program of underground or sub surface facilities in rock must be developed in accordance with the fundamental principle of Life Cycle Cost (LCC) for the purpose of managing maintenance work effectively and economically throughout the whole life of the infrastructures.This paper is introductory and expository in nature and discusses some of the issues associated operation and maintenance of rock structures/facilities with focus on LCC analysis.

  • 641.
    Kumar, Uday
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Maintenance management for modern mining equipment1996Ingår i: Journal of Mines, Metals and Fuels, ISSN 0022-2755, Vol. 44, nr 1, s. 25-29Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The old concept that maintenance is a necessary evil which costs what it costs is no longer valid and most of the leading mining companies are realising that the path to progress and success lies through integrating maintenance fully into the total business system of the company. The increasing scales of operation, the bigger-the better concept of mega sized equipment and the total integration of various processes and unit operations have given a new dimension to the problem of maintenance. Currently, many mining companies are shedding the traditional maintenance management styles in preference to the modern concept of the need based maintenance strategies where the concept of total productive maintenance (TPM) and that of reliability centered maintenance (RCM) are integrated. The mining industry all over the world with a few exceptions is still in transition phase as far as the question of maintenance management for large, complex and integrated systems in the mining industry is concerned. This paper reviews the recent trends and discusses some of the changes that are occurring in the area of maintenance of modern mining machinery and systems

  • 642.
    Kumar, Uday
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Maintenance strategies for mechanized and automated mining systems: a reliability and risk analysis based approach1998Ingår i: Journal of Mines, Metals and Fuels, ISSN 0022-2755, Vol. 46, nr 11, s. 343-347, 354Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The purpose of maintenance is to reduce business risk. In view of this, it is important that formal reliability and risk assessment form an integral part of the maintenance planning and control process. This article emphasizes the need of integration of risk analysis methods in all phases of conception, design, manufacturing and operation to arrive at the most optimal maintenance policies/strategies for the system under consideration. It also discusses various steps involved in risk analysis and concludes that the risk assessment can be used in many activities related to maintenance for arriving at the best decision among the several alternatives available at hand.

  • 643.
    Kumar, Uday
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Maintenance strategy for mechanized mining systems: a reliability analysis based approach1989Licentiatavhandling, monografi (Övrigt vetenskapligt)
  • 644.
    Kumar, Uday
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Philosophical aspects of modeling corrosion of oil and gas pipelines2007Ingår i: Proceedings of the 20th International Congress on Condition Monitoring and Diagnostic Engineering Management ; Faro, Portugal, June 13 - 15, 2007 ; COMADEM 2007: Congress theme: machinery & process health monitoring - future trends and prospects / [ed] Ana C.V. Vieira, Coimbra: IT - Instituto de Telecommunicações , 2007, s. 477-486Konferensbidrag (Refereegranskat)
  • 645.
    Kumar, Uday
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Product support issues for mining equipment and systems: opportunities and challenges2005Ingår i: Mine planning and equipment selection and computer applications in the minerals industries: proceedings ot the fourteenth International Symposium on Mine Planning and Equipment Selection (MPES 2005) and the fifth International Conference on Computer Applications in the Minerals industries (CAMI 2005) held jointly in Banff, Alberta, Canada, October 31-November 3, 2005 / [ed] Chris I Chiwetelu; Kostas Fytas; Raj K Singhal, Irvine, CA: Reading Matric , 2005, s. 1483-1490Konferensbidrag (Refereegranskat)
  • 646.
    Kumar, Uday
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Recent trends in mine maintenance technology and management1994Ingår i: Corrosion reviews, ISSN 0334-6005, E-ISSN 2191-0316, Vol. 12, nr 3-4, s. 191-200Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    During the last two decades there has been a marked tendency to design both large and complex equipment for mines. With the rapid pace of mechanization and automation in the mining industry, the image of the mine maintenance function has been undergoing a transformation in the last two decades. The capital outlay and ownership costs of the mining equipment and its importance for production requires that it is maintained in a good condition to ensure optimal performance and high safety levels. From an economic point of view, a high degree of reliability and maintainability is desirable to reduce maintenance costs. At present special emphasis is being placed on the RAM (reliability, availability and maintainability) characteristics of the mining equipment. Various methods and techniques are either being developed by the mining companies and equipment manufacturers, or are being adopted from other high-tech industries to ensure a high level of reliability and availability. Some efforts are also being made to study the effect of the working environment in mines, namely corrosion, dust, heat and humidity, etc. on the operating reliability of a mining system or equipment. The driving force behind this change in management thinking is the steep rise in maintenance costs during the 1980s. In this short paper some recent developments in mine maintenance technologies and management are discussed.

  • 647.
    Kumar, Uday
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Reliability analysis of Load-Haul-Dump machines1990Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Today, maintaining a mining equipment is an expensive affair. The two factors which influence significantly the occurrences of breakdowns are the operating reliability of equipment and the related human factors. The research work reported in the thesis is an attempt to control the occurrences of breakdowns and thereby the costs of maintenance by studying the operational reliability of the critical mining equipment. For the purpose of the reliability investigation, a fleet of load-haul-dump (LHD) machines deployed at Kiruna Iron Ore mine, Kiruna was selected. The times between successive failures of these machines and their main assemblies, namely the hydraulic, the engine, the brake and the transmission were analyzed for studying the reliability characteristics using the graphical methods in combination with analytical techniques. The results of the analysis show that it is very essential to test the field failure data for the presence of trends and serial correlations contrary to the approach adopted by most of the researchers today. It is shown that wrong conclusions can be drawn if such tests are not performed. When analyzed, the times between successive failures (TBFs) of LHD machines are found to be free from the presence of trends; and are exponentially distributed. However, most of the subsystems have shown increasing failure rate tendencies. The subsystems which have shown the existence of trends are analyzed using a time dependent model such as the power law process model. The growth in reliability over the years for the hydraulic systems is studied. contrary to the general expectation, no growth in reliability is noticed for such systems. Graphical methods for decision making in maintenance for both types of data, i.e. the TBFs with presence of a trend and the TBFs without a trend are presented. In this study simple and practical approaches are suggested for sorting and classification of the field failure data. The use of the homogeneous Poisson process model in place of the other best-fit models are examined. The application, methodology and benefits of implementation of reliability centered maintenance for the mining equipment is presented with example. Using the existing total time on test (TTT)-plotting technique, a graphical method is suggested for model validation and data analysis in case of repairable systems. During the course of this research study, a computer program called RELAN-G, i.e. Reliability Analysis with Graphics is developed which is a useful tool while performing reliability analysis.

  • 648.
    Kumar, Uday
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Reliability and risk based maintenance strategies1998Ingår i: Journal of Mines, Metals and Fuels, ISSN 0022-2755, Vol. XLV, nr 1, s. 76-80Artikel i tidskrift (Refereegranskat)
  • 649.
    Kumar, Uday
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Risk assessment in environment impact studies for mining projects1999Ingår i: Mine planning equipment selections 1999 & Mine environment and economical issues / [ed] G.G. Pivnyak; R.K. Singhal, Dnipropetrovsk: NMUU , 1999, s. 587-592Konferensbidrag (Övrigt vetenskapligt)
  • 650.
    Kumar, Uday
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Risk based maintenance strategies for mechanized and automated systems1998Ingår i: Proceedings of the 7th International Conference on Mine Planning and Equipment Selection: MPES-98, 1998, s. 647-651Konferensbidrag (Refereegranskat)
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