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  • 551.
    Kansal, Yogita
    et al.
    Amity Institute of Information Technology, Amity University.
    Kapur, Parmad Kumar
    Amity Center for Interdisciplinary Research, Amity University.
    Kumar, Uday
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Kumar, Deepak
    Amity Institute of Information Technology, Amity University.
    Prioritizing Vulnerabilities using ANP and Evaluating their Optimal Discovery and Patch Release Time2019Ingår i: International Journal of Mathematics in Operational Research (IJMOR), ISSN 1757-5850, E-ISSN 1757-5869, Vol. 14, nr 2, s. 236-267Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Method for filtering and identifying a vulnerability class that has high probability of occurrence is needed by organisations to patch their software in a timely manner. In this paper, our first step is to filter the most frequently observed vulnerability type/class through a multi-criteria decision making that involves dependency among various criteria and feedback from various alternatives, known as analytic network process. We will also formulate a cost model to provide a solution to the developers facing high revenue debt because of the occurrence of highly exploited vulnerabilities belonging to the filtered group. The main aim of formulating the cost model is to evaluate the optimal discovery and patch release time such that the total developer's cost could be minimised subject to risk constraints. To illustrate the proposed approach, reported vulnerabilities of Google Chrome with high exploitability have been examined at its source level.

  • 552.
    Kansal, Yogita
    et al.
    Amity Institute of Information Technology, Amity University, Noida.
    Kapur, P.K.
    Amity Centre of Interdisciplinary Research, Amity University, Noida.
    Kumar, Uday
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Kumar, Deepak
    Amity Institute of Information Technology, Amity University.
    Effort and coverage dependent vulnerability discovery modeling2018Konferensbidrag (Refereegranskat)
    Abstract [en]

    In this paper, our primary focus is to propose a generalized mathematical model that can discover potential vulnerabilities on the basis of two key factors: operational effort rate and operational coverage rate. Here, the term operational effort rate refers to the proportion of manpower required to discover vulnerabilities. The operational coverage rate refers to the proportion of software covered by the effort in discovering vulnerabilities. It is assumed that the proposed model follows the Non-Homogeneous Poisson process properties thus different distribution are used to formulate multiple cases. To evaluate the operational effort function, exponential and Weibull distribution are used considering coverage rate either to be a constant or logistic. For model validation, a case study of real commercial software data set has been used

  • 553.
    Kansal, Yogita
    et al.
    Amity Institute of Information Technology, Amity University.
    Kapur, P.K.
    Amity Centre for Interdisciplinary Research, Amity University.
    Kumar, Uday
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Kumar, Deepak
    Amity Institute of Information Technology, Amity University.
    User-dependent vulnerability discovery model and its interdisciplinary nature2017Ingår i: Life Cycle Reliability and Safety Engineering, ISSN 2520-1352, Vol. 6, nr 1, s. 23-29Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Software Vulnerability is a broad discipline that cannot be controlled only by the technologies. The holistic framework is required that statistically encompasses the entire security issues of IT organizations regardless of individual projects. Earlier researchers have developed several mathematical models that determined the vulnerabilities trend over time. Besides that, the most common victims of the vulnerabilities i.e., the software buyers or users were addressed theoretically without considering their impact on vulnerability discovery modeling. In this research paper, we examined the vulnerability discovery rate on the basis of potential users of commercial software. Here we propose an interdisciplinary model that highlights the relationship between the vulnerability intensity and the number of users of the software. The numerical illustration based on several real data sets is provided to validate the proposed user-dependent vulnerability discovery model.

  • 554.
    Kansal, Yogita
    et al.
    Amity Institute of Information Technology, Amity University.
    Kumar, Uday
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Kumar, Deepak
    Amity Institute of Information Technology, Amity University.
    Kapur, Parmad Kumar
    Amity Centre for Interdisciplinary Research, Amity University, Noida.
    Fixing of Faults and Vulnerabilities via Single Patch2018Ingår i: Quality, IT and Business Operations: Modeling and Optimization / [ed] Kapur P., Kumar U., Verma A., Singapore: Springer, 2018, s. 175-190Kapitel i bok, del av antologi (Refereegranskat)
    Abstract [en]

    Users’ demand of reliable software in zero time has made the software development more complex. If software industry fails in fulfilling the demands, then it may undergo big penalties and revenue loss. The developers are pressurized subject to resource constraints provided by the management. Despite such fact, software experiences various validation (testing) processes before its release; faults and vulnerabilities are still left undetected that later lack the quality of the product. The only feasible solution for resisting from the lack after the release of software is patch development. Generally, the patches developed for fixing faults and vulnerabilities are a separate process which requires extra resources that increases the total development cost and time. In this paper, we have proposed a cost framework that solves the problem of optimizing the patch release time with two different approaches. Here, the first approach has considered the release of a single patch that fixes both faults and vulnerabilities jointly. As the severity of vulnerabilities is much higher than the faults, the second approach considered the release of two patches where the first patch has fixed both faults and vulnerabilities jointly and other patch specifically fixed only vulnerabilities. The detailed illustration of the method is presented in the proposed paper. The case study is presented at the end for the validation purpose.

  • 555.
    Kansal, Yogita
    et al.
    Amity Institute of Information Technology, Amity University.
    Singh, Gurinder
    Amity International Business School, Amity University.
    Kumar, Uday
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Kapur, P.K.
    Amity Center for Interdisciplinary Research, Amity University, .
    Optimal release and patching time of software with warranty2016Ingår i: International Journal of Systems Assurance Engineering and Management, ISSN 0975-6809, E-ISSN 0976-4348, Vol. 7, nr 4, s. 462-468Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    As we know in a competitive market, software firms are looking to sell their products at the earliest for maximum gains. Early delivery of a product is beneficial in terms of gaining market potential but may include some defects in it. On the other hand late delivery of a product ensures reliability but may results into disinterest of the customers. Thus, a vendor must focus on the best time for releasing the software. In recent times, early software release and updating it by providing patches in the operational phase is in trend. Also to satisfy customer’s primary concern of reliable software, firms are providing warranty on their products. Warranty period is the time in which firm provide assurance to the customers that under this period product will work properly and if any defect is found, firm will either repair or replace the software without charging the customer. But servicing during warranty period by updating with patches is also not economical from firm’s point of view. Hence it is important to find the optimal patch release time. In this paper we have proposed a generalized framework to find out the optimal release and patching time of software under warranty so that the total cost is minimized. Numerical example is given at the end to validate the proposed cost model.

  • 556.
    Kapur, P.K.
    et al.
    Amity University, Department of Operational Research, University of Delhi.
    Aggarwal, Anu G.
    Delhi University.
    Garmabaki, Amir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Tandon, Abhishek
    Multi-generational innovation diffusion modelling: a two dimensional approach2015Ingår i: International Journal of Applied Management Science, ISSN 1755-8913, E-ISSN 1755-8921, Vol. 7, nr 1, s. 1-18Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Majority of the consumer durables have multiple technological generations. High technology product comes in new generation where a new innovation offers a significant improvement in performance or benefits over the previous generation. New innovation in the market does not immediately replace the previous one that it intends to substitute, but starts to compete with it. This creates a sequence of parallel diffusions of the existing generational products in the market. In this paper, we develop a two-dimensional multigenerational innovation diffusion model which combines the adoption time of technological diffusion and price of the technology product. The proposed model helps in studying the marketing dynamics of the products which comes in generations. Technological adoptions and the role of the other dimensions are explicitly taken into consideration using Cobb-Douglas function. Empirical implications of the proposed model have been validated on data collected from DRAM (Semiconductor Industry DRAM shipments of six generations) in two plans.

  • 557.
    Kapur, P.K.
    et al.
    Amity Center for Interdisciplinary Research, Amity University, .
    Kumar, Uday
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Special issue on reliability, infocomm technology and business operations2016Ingår i: International Journal of Systems Assurance Engineering and Management, ISSN 0975-6809, E-ISSN 0976-4348, Vol. 7, nr 4, s. 399-Artikel i tidskrift (Refereegranskat)
  • 558.
    Kapur, P.K.
    et al.
    Amity University.
    Kumar, Uday
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Nitin, Sachdeva
    Amity University.
    Adarsh, Anand
    University of Delhi.
    Optimal price and warranty length2012Ingår i: Communications in Dependability and Quality Management, ISSN 1450-7196, Vol. 15, nr 1, s. 5-13Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    With rapid advancement in technologies in the last few decades organizations today have shifted their focus from being product centric to customer/market driven. With post sales services like providing warranty playing an influential role in the purchase of new product, manufacturers today are leaning towards optimizing warranty length & price of their products in order to ensure profitability. In this paper treating optimal warranty length and price of goods as decision variables, we intend to maximize overall profit for producers under the influence of a combination of free replacement and pro-rata warranty policies. Two-dimensional innovation diffusion model incorporating both price and warranty length is employed to demonstrate product sales cycle. Exponential distribution is used to represent the lifetime of a product. To elucidate application of the model real data set is presented as illustration.

  • 559.
    Kapur, P.K.
    et al.
    Amity Center for Interdisciplinary Research, Amity University.
    Kumar, UdayLuleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.Verma, Ajit KumarWestern Norway University of Applied Sciences, Haugesund .
    Quality, IT and Business Operations: Modeling and Optimization2018Samlingsverk (redaktörskap) (Refereegranskat)
    Abstract [en]

    This book discusses action-oriented, concise and easy-to-communicate goals and challenges related to quality, reliability, infocomm technology and business operations. It brings together groundbreaking research in the area of software reliability, e-maintenance and big data analytics, highlighting the importance of maintaining the current growth in information technology (IT) adoption in businesses, while at the same time proposing process innovations to ensure sustainable development in the immediate future. In its thirty-seven chapters, it covers various areas of e-maintenance solutions, software architectures, patching problems in software reliability, preventive maintenance, industrial big data and reliability applications in electric power systems.

    The book reviews the ways in which countries currently attempt to resolve the conflicts and opportunities related to quality, reliability, IT and business operations, and proposes that internationally coordinated research plans are essential for effective and sustainable development, with research being most effective when it uses evidence-based decision-making frameworks resulting in clear management objectives, and is organized within adaptive management frameworks. Written by leading experts, the book is of interest to researchers, academicians, practitioners and policy makers alike who are working towards the common goal of making business operations more effective and sustainable.

  • 560.
    Kapur, P.K.
    et al.
    Department of Operational Research, University of Delhi.
    Kumar, Uday
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Verma, A.K.
    International Institute of Information Technology, P-14, Pune Infotech Park, Phase-1, Hinjawadi.
    Preface2010Ingår i: International Journal of Reliability, Quality and Safety Engineering (IJRQSE), ISSN 0218-5393, Vol. 17, nr 3, s. v-viArtikel i tidskrift (Övrigt vetenskapligt)
  • 561.
    Kapur, P.K.
    et al.
    Amity University.
    Srividya, A.
    University College, Haugesund.
    Galar, Diego
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Foreword2013Ingår i: International Journal of Reliability, Quality and Safety Engineering (IJRQSE), ISSN 0218-5393, Vol. 20, nr 3, s. 1-2Artikel i tidskrift (Övrigt vetenskapligt)
  • 562.
    Karadimou, Eva
    et al.
    York EMC Services.
    Armstrong, Robert A.
    York EMC Services.
    Adin, Iñigo
    CEIT.
    Deniau, Virgine
    IFSTTAR.
    Rodriguez, Joseba P.
    CAF-ID.
    Galar, Diego
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Niska, Stefan
    Trafikverket.
    Tamarit, Jaime
    CEDEX, Centro de estudios y experimentación de obras públicas.
    An EMC study on the interopability of the European railway network2015Ingår i: IEEE International Symposium on Electromagnetic Compatibility (EMC), 2015 [joint conference with] EMC Europe: 16-22 Aug. 2015, Dresden, Piscataway, NJ: IEEE Communications Society, 2015, s. 428-433, artikel-id 7256200Konferensbidrag (Refereegranskat)
    Abstract [en]

    The research presented here deals with the electromagnetic compatibility in the railway environment. In particular it focuses on four research areas: the spot signalling systems, the track circuits, the GSM-R and the broadcasting services. A review of the current railway standards is followed by a research on the immunity limits, the worst case scenarios and cross acceptance EMC tests for the four areas

  • 563.
    Karim, M.R.
    et al.
    Department of Statistics, University of Rajshahi.
    Ahmadi, Alireza
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Murthy, D.N.P
    School of Mechanical and Mining Engineering, The University of Queensland, St Lucia.
    Modelling of Maintenance Data2016Ingår i: Current Trends in Reliability, Availability, Maintainability and Safety: An Industry Perspective / [ed] Uday Kumar; Alireza Ahmadi; Ajit Kumar Verma; Prabhakar Varde, Encyclopedia of Global Archaeology/Springer Verlag, 2016, s. 409-424Konferensbidrag (Refereegranskat)
    Abstract [en]

    The modelling of maintenance data starts with the black-box approach (where the model selection is based solely on the maintenance data) and then through the grey-box approach for proper analysis (where one can gain insights to build better models). These models allow for more effective maintenance of the object. This paper deals with the grey-box approach to modelling. It discusses the process of modelling and illustrates this through a real case study

  • 564.
    Karim, Ramin
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    A service-oriented approach to e-maintenance of complex technical systems2008Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    In today's global business scenarios, an organization can strengthen its com-petitiveness by offering a spectrum of industrial services that range from tra-ditional customer support to turnkey solutions. To achieve this service spec-trum, it is necessary to manage information consumption and production at right quality level in right time. When dealing with complex technical systems, e.g. military aircraft, with long life cycles, the management of maintenance-related information is crucial to fulfil stringent dependability, Life Support Cost (LSC) and safety requirements. Today, there is available Information & Communication Technology (ICT) to realize an eMaintenance solution for the necessary information logistics. However, there is a lack of appropriate frameworks, methodologies and tools that enable a service-oriented approach to eMaintenance. Hence, the purpose of this research is to explore and describe how an eMaintenance solution can be developed to provide information services that support the maintenance of complex technical systems. To fulfil the purpose, a major case study within military aviation has been performed, supported by two minor case studies within the healthcare sector and the process industry. Empirical data has been collected through interviews, observations, archival records and workshops. The analysis is based on developed theoretical frameworks, Design of Experiment (DoE) principles and available interna-tional standards. The results of this research are: I) an exploration and definition of eMaintenance; II) a description of eMaintenance as support to maintenance of complex technical systems; III) an eMaintenance Management Framework (eMMF) for establishment of an eMaintenance platform; and IV) a methodology with a supporting toolbox that facilitates the identification of maintenance support information.

  • 565.
    Karim, Ramin
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Design pattern for development and maintenance of geographical IT systems2005Licentiatavhandling, monografi (Övrigt vetenskapligt)
    Abstract [en]

    The information society, having a growing information domain/amount, requires a reliable information infrastructure with ability to distribute the right information from the right information producer to the right information consumer, at the right time and with the right quality on demand (information-on-demand). Another growing demand, parallel with the information distribution infrastructure, is information visualization. Information visualization is one of the important tools that help consumers to interpret and understand the distributed data, and facilitate the decision-making process. Maps have always been a popular method for visualizing spatial objects, objects that contain spatial references such as address co-ordinates and building ID. The rapidly growing need for geographical information systems (also called GI systems/applications) and components has an impact on the processes of development and maintenance of geographical information systems and components. The main purpose of this research is to study design patterns and suggest methods, models, rules of thumb and so on to improve the process of development and maintaining geographical information systems and reduce the total life cycle cost. The main objective is divided into following sub objectives, namely, a) to describe different patterns, solutions, models, suggestions and recommendations that can improve the process of developing GI-applications in order to reduce the cost of producing, developing and maintaining applications with a high level of quality and serviceability, b) to examine if and how the idea of design pattern is applicable to the architecture of software with spatial components (commonly called GI systems), c) to identify the factors that impact the costs of GI software development and maintenance processes and if possible recommend a model for reducing the cost and improving the quality of the solutions, d) to find and suggest solutions, models, rules of thumb, suggestions and recommendations that can improve the process of developing GI-applications. During the study, it has been noticed that recurrent GI-problems are solved but those solutions are hardly communicated among developers. On the basis of software developed in many of the research projects and also students' works we have observed that the architecture of GI software is in most cases similar to any other software. This similarity makes it possible to apply general software development patterns to GI applications. Further more it is noticed that recurring problems are not dependent on who the developer is or to what category she or he belongs, but on the problem situation and the context of the application. This means that the developer faces almost the same kinds of problems in a given situation. It has also been noticed that the size of projects and demands from customers, management, development organisations and culture/experiences, maintenance organisations and so on have an effect on how much the developer group need to use patterns and semi-manufactured components during the software development process. The study has shown that generic IT patterns can be used for designing GI-applications, but there is still a need for technology- and product-specific patterns for GI- components

  • 566.
    Karim, Ramin
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    ePilot 2.0 - Final Report2020Rapport (Övrig (populärvetenskap, debatt, mm))
  • 567.
    Karim, Ramin
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Project: eMaintenance infrastructure for enhanced information logistics2010Övrigt (Övrig (populärvetenskap, debatt, mm))
    Abstract [en]

    The availability of qualified operational data and information from the operational use of complex aircraft system is becoming increasingly important and more valuable for both operators and suppliers of aircraft system. An example is Airbus, which lets customers offset a significant part of the cost of support received by Airbus if they provide operational and maintenance data. Another example is Saab's availability contract for SK60, where a faster feedback of operational and maintenance data in (near) real time is critical for control of  flight production and contract monitoring. Traditional Operational Performance Monitoring (OPM), with a focus on monitoring of airworthiness, and system evaluations for Life Cycle Management (LCM) are often done, e.g. annually. Increased demands on aircraft system and maintenance providers to improve availability and dependability through availability-focused maintenance, reducing Life Cycle Cost (LCC) and Life Support Cost (LSC) and the introduction of performance-based business models (Performance-Based Logistics, PBL and Contracted Logistic Support, CLS) introduces new and more stringent demands on OPM and LCM. Access to relevant operational and maintenance data, and the use of OPM and LCM as analytical tools and control instruments are becoming increasingly important to manage the technical and commercial risks inherent in changing maintenance solutions (eg, dynamic maintenance plans) and new business models. At the same time, the quality of data, existing Information & Communication Technology (ICT), tools, manual intervention and outdated information security and privacy solutions are often a limitation for the development of OPM, LCM and other qualified support services, which are necessary to streamline operation and maintenance and to support PBL and CLS.The project aims to improve the infrastructure for data and information exchange between operators and suppliers to identify, adapt and integrate ICT-based methods and solutions for a so-called eMaintenance-infrastructure, enabling improved efficiency and further development of primary OPM and LCM in support of PBL/CLS, dynamic maintenance schedules and new information-based decision-support services for operation, maintenance and support.

  • 568.
    Karim, Ramin
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Project: Innovative eMaintenance Services For Primary Industries and SMEs2011Övrigt (Övrig (populärvetenskap, debatt, mm))
  • 569.
    Karim, Ramin
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Birk, Wolfgang
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Signaler och system.
    Larsson-Kråik, Per-Olof
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Cloud-based emaintenance solutions for condition-based maintenance of wheels in heavy haul operation2015Ingår i: 11th International Heavy Haul Conference, (IHHA 2015): 21 – 24 June 2015, Perth, Australia, International Heavy Haul Association , 2015Konferensbidrag (Refereegranskat)
    Abstract [en]

    The Swedish ore line, began in 1898 and was completed and operational by 1902. The line was later electrified and remains so to this day. A study on wheel-rail interaction, to optimize wheel and rail profiles on the Malmbanan and Ofoten lines states that there is a need to develop and apply limit values for the allowable length of single and multiple cracks on wheels. Herein, all stakeholders in the railway organization have to be involved. Provisioning of an integrated decision support system for track and vehicle contributes to increased efficiency and improved effectiveness of the maintenance process, which in turn enables achievement of business excellence. However, an integrated decision support process for maintenance is highly dependent on appropriate information logistics which enables information provisioning to various maintenance stakeholders. One emerging approach for development of eMaintenance solutions is utilization of cloud-based technologies. Cloud-based eMaintenance solutions promises smooth information logistics for maintenance decision support. Hence, the purpose of this paper is to propose an approach for condition-based maintenance decision-making relating to railway vehicle wheels, based on a cloud-based eMaintenance solution. The paper also demonstrates how the proposed approach can be implemented for estimation of Remaining Useful Life (RUL) of railway vehicle wheels.

  • 570.
    Karim, Ramin
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Candell, Olov
    Söderholm, Peter
    Development of ICT-based maintenance support services2009Ingår i: Journal of Quality in Maintenance Engineering, ISSN 1355-2511, E-ISSN 1758-7832, Vol. 15, nr 2, s. 127-150Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Purpose - The purpose of this paper is to describe a taxonomy for an eMaintenance management framework (eMMF) based on a service-oriented approach, in order to facilitate the development of information and communication technology (ICT)-based maintenance support services aimed at actors within the maintenance process related to complex technical industrial systems. Design/methodology/approach - To fulfil this purpose, a case study of a modern multi-role combat aircraft is selected as an appropriate research strategy and supported by a literature study. Empirical data are collected through interviews, workshops, document studies, and observations. A framework is developed and evaluated using a prototype within the studied case. The study is performed in close cooperation with the aircraft's type certificate holder and the customer representative and operator in one country. Findings - The proposed eMMF aids in the identification and development of ICT-based maintenance support services tailored for specific maintenance actors and their activities. Research limitations/implications - To further test the usefulness of the proposed framework, a larger scale application must be performed. This can involve additional stakeholders or a larger part of the technical system in the selected case, or another case dealing with complex technical industrial systems. Practical implications - The proposed framework supports the identification of required information services that support the maintenance process, which in turn supports the development of a service-oriented architecture (SOA) aimed at proper maintenance information logistics. Hence, people working with information logistics for maintenance purposes can use the framework as a support tool. Originality/value - The proposed framework combines a process and service-oriented approach, which facilitates the development of SOA-based information services by giving valuable input to more traditional system-oriented approaches

  • 571.
    Karim, Ramin
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Candell, Olov
    Söderholm, Peter
    E-maintenance and information logistics: aspects of content format2009Ingår i: Journal of Quality in Maintenance Engineering, ISSN 1355-2511, E-ISSN 1758-7832, Vol. 15, nr 3, s. 308-324Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    PurposeThe purpose of this paper is to describe aspects of content sharing within eMaintenance, with a view to merging the two areas of maintenance and ICT in a content management perspective. The purpose of this paper is to describe aspects of content sharing within eMaintenance, with a view to merging the two areas of maintenance and ICT in a content management perspective. Design/methodology/approachThe approach is an explorative literature study covering aspects of ICT. The analysis was founded on theories related to maintenance and maintenance support. The conclusions of the study are corroborated by experiences from earlier software development and testing. The approach is an explorative literature study covering aspects of ICT. The analysis was founded on theories related to maintenance and maintenance support. The conclusions of the study are corroborated by experiences from earlier software development and testing. FindingsMost existing contributions to the eMaintenance debate seem to suffer from too wide a gap between data processing and knowledge management. This tendency can be due to too great a focus on data collection, without any clear identification of the stakeholders‟ requirements. Hence, a mature eMaintenance solution should focus on the enhancement of service-oriented information logistics based on content sharing for an output-based information strategy. Most existing contributions to the eMaintenance debate seem to suffer from too wide a gap between data processing and knowledge management. This tendency can be due to too great a focus on data collection, without any clear identification of the stakeholders‟ requirements. Hence, a mature eMaintenance solution should focus on the enhancement of service-oriented information logistics based on content sharing for an output-based information strategy. Research limitations/implicationsThis study focuses on the needs of content format and transformation content, which includes data format, data structures and data type for objects that are relevant for the maintenance process. Hence, further research could include aspects of infrastructure and service architecture, which are on a higher level of an eMaintenance solution. This study focuses on the needs of content format and transformation content, which includes data format, data structures and data type for objects that are relevant for the maintenance process. Hence, further research could include aspects of infrastructure and service architecture, which are on a higher level of an eMaintenance solution. Practical implicationsThe paper contributes with knowledge that supports decisions about content format in the development of an eMaintenance solution. This can in turn support a reduction of maintenance-related hazards through improved use of ICT. The paper contributes with knowledge that supports decisions about content format in the development of an eMaintenance solution. This can in turn support a reduction of maintenance-related hazards through improved use of ICT. What is original/value of paperThis paper describes the importance of content management within the eMaintenance approach. Hence, the paper has implications for both practitioners and researchers as described above. This paper describes the importance of content management within the eMaintenance approach. Hence, the paper has implications for both practitioners and researchers as described above.

  • 572.
    Karim, Ramin
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Jägare, Veronica
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    ePilot: Slutrapport : ett samverkansprojekt inom järnväg2017Rapport (Övrig (populärvetenskap, debatt, mm))
  • 573.
    Karim, Ramin
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Jägare, Veronica
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Lindberg, Rune
    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.
    Robust and Reliable Transport System: A strategic agenda for resource pooling, collaboration, innovation and research2015Rapport (Övrig (populärvetenskap, debatt, mm))
    Abstract [sv]

    Sverige och omvärlden står inför stora utmaningar med ett ständigt ökande transportbehov där dagens och framtidens hållbarhets- och klimatkrav ska uppfyllas. Med stora avstånd och relativt liten befolkning har Sverige en unik uppsättning transportbehov, och med en åldrande infrastruktur skärps utmaningarna ytterligare. Agendan vill staka ut den strategiska vägen för framtidens väg- och järnvägstransporter.Visionen är att möjliggöra ett robust, motståndskraftigt och pålitligt transportsystem som samtidigt är attraktivt, säkert hållbart och effektivt. Denna vision ska realiseras genom tre huvudsakliga delmål

    • förbättrad ekonomisk, samhällelig och miljömässig effektivitet
    • reducerade störningar – de närmaste fem åren ska två tredjedelar av de störningar som påverkar transportkvalitet och klimat vara borta
    • utökad samverkan och samarbete mellan industri, politik och akademi ska skapa en systemsyn med kvalitet i transporter som mål.

    För att målbilden ska bli verklighet behöver insatser bedrivas inom fyra fokusområden

    • styrning av transportsystemet
    • innovation i transportsystemet
    • godstransporter och passagerartrafik
    • intelligent transportsystem.

    Inom fokusområdena ska särskild vikt läggas på ett antal kärnaktiviteter, bland annat:

    • nätverkande mellan olika aktörer och organisationer
    • idéfora för innovationsprojekt
    • forskning
    • noder av testmiljöer
    • uppstartsstöd
    • tillväxtsstöd för små och medelstora företag.

    Agendans insatsområden ska mötas genom nära samverkan mellan aktörerna i ett incitamentdrivet trippelhelix med ett holistiskt systemperspektiv. Aktörerna i samverkan omfattar infrastrukturförvaltare, trafikutövare, akademi och institut, design- och projekteringskonsulter, systemleverantörer, entreprenadföretag och underhållsföretag.

  • 574. Karim, Ramin
    et al.
    Kajko-Mattsson, Mira
    Department of Computer and Systems Sciences, Stockholm University, Royal Institute of Technology.
    Söderholm, Peter
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Exploiting SOA within emaintenance2008Ingår i: Proceedings of the 2nd international workshop on Systems development in SOA environments: International Conference on Software Engineering. Session: SOA supporting business process management (BPM), Piscataway, NJ: IEEE Communications Society, 2008, s. 75-80Konferensbidrag (Refereegranskat)
    Abstract [en]

    SOA is being exploited in many various business domains. One of them is industrial maintenance. In this paper, we outline an eMaintenance Platform (eMP) for maintaining complex technical systems. This platform is part of the eMaintenance Management Framework (eMMF). Our primary goal is to explore how SOA can be exploited within industrial maintenance. Our secondary goal is to provide eMP as an effective tool for organizations to conduct their maintenance and support.

  • 575.
    Karim, Ramin
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Kajko-Mattsson, Mira
    Stockholm University and KTH.
    Söderholm, Peter
    Candell, Olov
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Tyrbern, Tommy
    Saab Aerotech.
    Öhlund, Hans
    Swedish Air Force Wing F21.
    Johansson, Jan
    Swedish Defence Materiel Administration.
    Positioning embedded software maintenance within industrial maintenance2008Ingår i: 2008 IEEE International Conference on Software Maintenance: [ICSM 2008] ; Beijing, China, 28 September - 4 October 2008, Piscataway, NJ: IEEE Communications Society, 2008, s. 440-443Konferensbidrag (Refereegranskat)
    Abstract [en]

    Little is known about of how software embedded in complex industrial technical systems is maintained. In this paper, we identify industrial maintenance process steps and position software maintenance activities within them. We do this in the context of JAS 39 Gripen, a multi-role combat aircraft developed by Saab.

  • 576. Karim, Ramin
    et al.
    Kumar, UdayLuleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.Parida, Aditya
    Proceedings of the 1st international workshop and congress on eMaintenance2010Samlingsverk (redaktörskap) (Övrigt vetenskapligt)
  • 577. Karim, Ramin
    et al.
    Parida, Aditya
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    eMaintenance readiness of Swedish process industry: a case study2010Ingår i: International Journal of COMADEM, ISSN 1363-7681, Vol. 13, nr 3, s. 18-24Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The business scenario is focusing more on e-business intelligence to perform transaction with customers needs for enhanced value and improvement in asset management. Such prognostic business requirement is compelling the organizations to minimize the production and service downtime by reducing the machine performance degradation. The purpose of this paper is to undertake a mapping of the present status of the maintenance of the Swedish process industry, study their linkage and correlation between the business and maintenance processes, and the supporting Information & Communication Technology (ICT), in order to identify the feasibilities and challenges for implementing eMaintenance system. The focus of the work was to identify how the current maintenance process is defined, organized and performed; and how it is linked and correlated to the business and support processes and besides what is executed within the maintenance process.

  • 578.
    Karim, Ramin
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Parida, Aditya
    Service-oriented information logistics as support to asset management of complex technical systems2009Konferensbidrag (Refereegranskat)
    Abstract [en]

    The global business scenario under the economic slowdown demands an increased environmental sustainability of asset during its whole life cycle, besides the other requirements like, Life Support Cost (LSC) and availability performance. To fulfill these requirements, a need exist for introducing asset management philosophy with integrated management strategy. Further, an effective asset management is also dependent on other prerequisites such as a proper support infrastructure, which include human resources, support equipment, materials and spare parts, facilities, documentation, information and information systems. Information is essential in order to facilitate asset management and enable the achievement of overall business objectives. Hence, asset related information need to be provided through a proper information logistics.Information logistics aims to provide just-in-time information to the actors of asset management and to optimize the information supply process, i.e. making the right information available at the right time and at the right point of location. In this context the delivery of accurate and timely information to the information consumer and its adaption to the right situation is highly important.Information logistics for an extensive information context related to complex technical systems with capability such as mobility, real-time delivery, context-awareness and situation-awareness requires appropriate methodologies and technologies. These methodologies and technologies are aimed to be utilized to provide an efficient ICT infrastructure, context-dependent extraction of complex data and information and also to facilitate autonomous decision-making and control. Furthermore, since asset management is a process that should consider all phases of a systems whole lifecycle, e.g. conceptual design; preliminary system design; detailed system design and development; production and construction; utilisation and support; and retirement and disposal; its related information logistics also needs to provide capability to manage information from all inherent phases of the system lifecycle. However, establishment of appropriate information logistics including mechanism for time management, which addresses 'when to deliver'; content management, which refers to 'what to deliver'; communication management, which refers to 'how to deliver'; and context management, which addresses 'where and why to deliver' throughout all phases of a system lifecycle is a great challenge, since necessary information is often hidden among vast quantities of data, stored for other purposes, in different places, and in different formats, and generated throughout the entire lifecycle of a system. Hence, it is commonly realized that the establishment of a dynamic and effective solution for information logistics requires appropriate software architecture and related infrastructure. However, the ultimate goal of information logistics in this context is to support the asset management process to achieve the overall business objectives through provision of information to its stakeholders. This paper describes a service-oriented approach to establishment of information logistics related to asset management of complex technical system within the context of military aviation.

  • 579.
    Karim, Ramin
    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.
    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.
    eMaintenance industrial applications: issues and challenges2014Ingår i: Engineering Asset Management 2011: Proceedings of the Sixth World Congress on Engineering Asset Management / [ed] Jay Lee; Jun Ni; Jagnathan Sarangapani; Joseph Mathew, New York: Encyclopedia of Global Archaeology/Springer Verlag, 2014, s. 33-40Konferensbidrag (Refereegranskat)
    Abstract [en]

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

  • 580.
    Karim, Ramin
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Parida, Aditya
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Kumar, Uday
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Condition Monitoring and eMaintenance: Condition Monitoring and eMaintenance2014Ingår i: Journal of Quality in Maintenance Engineering, ISSN 1355-2511, E-ISSN 1758-7832, Vol. 20, nr 3Artikel i tidskrift (Refereegranskat)
  • 581.
    Karim, Ramin
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Parida, AdityaLuleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.Kumar, UdayLuleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Proceedings of the 2nd International Workshop & Congress on eMaintenance: Dec 12-14 Luleå, Sweden : eMaintenace: trends in technologies and methodologies, challenges, possibilities and applications2012Samlingsverk (redaktörskap) (Övrigt vetenskapligt)
    Abstract [en]

    Compilation of papers presented in the technical sessions during the eMaintenance 2012.

  • 582.
    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.
    An enterprise risk management framework for evaluation of eMaintenance2010Ingår i: International Journal of Systems Assurance Engineering and Management, Vol. 1, nr 3, s. 219-228Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Maintenance is one approach to managing 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 a technical system’s health to a true risk-based maintenance approach that also considers organizational 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 and com- munication technology (ICT). However, all opportunities are also linked with some threats, which are seldom high- lighted in the case of eMaintenance. In this article, a risk management framework for evaluation of eMaintenance solutions is proposed. The framework is based on a combi- nation of international standards (e.g. ISO 31000, ISO/IEC 27000, and IEC (2004) 60300-3-14) to achieve integrated Enterprise Risk Management (ERM) and enable a linkage of eMaintenance to the strategic goals of an organization. Theframework is illustrated in the railway context of Trafik- 30verket (2010b) (the Swedish Transport Administration).

  • 583.
    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.

  • 584.
    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.

  • 585.
    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”.

  • 586.
    Kassfeldt, Elisabet
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Maskinelement.
    Lundberg, Jan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Lubricant capability in squeeze-sliding motion1993Ingår i: Thin films in tribology: proceedings of the 19. Leeds-Lyon Symposium on Tribology, held at the Institute of Tribology, University of Leeds, U.K., 8. - 11. September 1992 / [ed] Duncan Dowson, Amsterdam: Elsevier, 1993, s. 255-261Konferensbidrag (Refereegranskat)
    Abstract [en]

    Nine different types of commercial lubricants have been tested in an apparatus which can produce squeeze and sliding motion simultaneously. It is found that lubricants with the same viscosity show big differences in lubricant capability in terms of wear and oil film collapse, and that these differences are due to the additives

  • 587.
    Kayrbekova, Dina
    et al.
    University of Stavanger.
    Ghodrati, Behzad
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Markeset, Tore
    University of Stavanger.
    Life cycle cost modeling in oil and gas production facilities in harsh, remote and sensitive environments2008Konferensbidrag (Refereegranskat)
    Abstract [en]

    Design of oil and gas production facilities in harsh, remote and sensitive environments pose a challenge for companies. Several life cycle cost (LCC) analysis methodologies are in use, but due to new design constraints imposed by the location, the climate as well as governmental regulations concerning pollution and protection of the environment in general, these methodologies are not easy to apply. The goal is to apply the LCC concept and to design for operational, maintenance and support service strategies to reduce risks. This paper discusses issues of life cycle cost analysis applied to operations, maintenance and support of an advanced, complex and integrated offshore oil and gas production plant to be used in harsh, sensitive and remote environments. The challenges influencing the life cycle cost analysis of such a facility is identified and discussed. An improved version of LCC analysis called activity-based LCC is addressed as well. The focus is on the design of an offshore production facility to be used in the Goliat oil and gas field located in the southern Barents Sea in the north of Norway.

  • 588.
    Kayrbekova, Dina
    et al.
    University of Stavanger.
    Markeset, Tore
    University of Stavanger.
    Ghodrati, Behzad
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Activity based life cycle analysis as an alternative to conventional LCC in engineering design2011Ingår i: International Journal of Systems Assurance Engineering and Management, ISSN 0975-6809, E-ISSN 0976-4348, Vol. 2, nr 3, s. 218-225Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Petroleum exploration and production in the Arctic region is becoming of increasing interest as the world needs more energy. However, since there is little experience and data on Arctic oil and gas production, the design of production facilities and equipment to be used in the Arctic region is fraught with high cost and risk. Conventional life cycle costing (LCC) approaches have been discussed in literature for many years, but it is difficult to perform such analysis due to the need of large amount of data and the inherent uncertainty in the results. There also is little evidence in the literature on practical usage of LCC. In this paper we discuss the differences between conventional LCC and activity-based LCC (AB-LCC) cost systems. Moreover, based on an analytical comparison between the two methodologies we find that the AB-LCC methodology may be a better alternative to use for cost analysis in the design of production facilities to be used in unfamiliar environments such as the Arctic. A simple numerical example is used to demonstrate the differences between conventional LCC and AB-LCC analysis.

  • 589.
    Khajehei, Hamid
    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.
    Soleimanmeigouni, Iman
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Nissen, Arne
    Trafikverket, Luleå, Sweden.
    Allocation of effective maintenance limit for railway track geometry2019Ingår i: Structure and Infrastructure Engineering, ISSN 1573-2479, E-ISSN 1744-8980, Vol. 15, nr 12, s. 1597-1612Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The objective of this study has been to develop an approach to the allocation of an effective maintenancelimit for track geometry maintenance that leads to a minimisation of the total annual maintenancecost. A cost model was developed by considering the cost associated with inspection, preventivemaintenance, normal corrective maintenance and emergency corrective maintenance. The standarddeviation and extreme values of isolated defects of the longitudinal level were used as quality indicatorsfor preventive and corrective maintenance activities. The Monte Carlo technique was used tosimulate the track geometry behaviour under different maintenance limit scenarios and the effectivelimit was determined which minimises the total maintenance cost. The applicability of the model wastested in a case study on the Main Western Line in Sweden. Finally, a sensitivity analysis was carriedout on the inspection intervals, the emergency corrective maintenance cost and the maintenanceresponse time. The results show that there is an optimal region for selecting an effective limit.However, by considering the safety aspects in track geometry maintenance planning, it is suggestedthat the lower bound of the optimal region should be selected.

  • 590.
    Khan, Saad Ahmed
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Effects of top-of-rail friction modifiers on the friction, wear and cracks of railway rails2019Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    The railway is an economical and environmentally friendly mode of transport for long distances and heavy loads. The demands on the operators are increasing with increased competition in the market, and therefore they are currently demanding more track capacity. In the short term, the existing network is expected to deliver the increased capacity. In order to achieve increased capacity without introducing double track, either the axle load or the number of trains (i.e. the annual gross tonnage) needs to be increased, which will decrease the life of the rail and thus increase the maintenance cost. To increase the lifetime of the rails without compromising with regard to the axle load and speed, one must increase the strength of the rails, decrease the traction forces between the rails and wheels, or introduce a third body with anti-wear and anti-crack properties that can reduce the wear and rolling contact fatigue (RCF) without reducing the traction forces below the safety limit.

    The traction forces depend on several variables, for example third bodies in the wheel-rail interface, the train dynamics, the wheel and rail profiles, etc. Third bodies in the wheel-rail interface are one of the important influencing factors. The additive third bodies with anti-wear properties and friction reduction capabilities reduces both the wear and the RCF. However, a friction coefficient in the wheel tread and the top of the rail below 0.3 can cause slippage and a long braking distance. To reduce the degree of utilised friction to a value close to 0.35 from dry conditions with a value of 0.55, and thereby reduce the wear, a product known as top-of-rail friction modifier (TOR-FM) was developed in North America and presented in 2003 at the heavy haul conference. The TOR-FM manufacturers claim that their products provide a fixed range of friction coefficients (μ) and Kalker’s coefficients in the wheel-rail interface. Kalker’s coefficient considers the tendency of creepage between the rail and wheel as a function of the traction forces at lower creepage levels. Field and laboratory tests in the USA, Canada and China have determined the benefits of using friction control products, which include the reduction of RCF, wear, corrugation, bogie hunting, noise, and fuel consumption without any side effects. In contrast, researchers at Luleå University of Technology (LTU) have found that such products in certain conditions give unacceptably low friction that can cause long braking distances and slippage. Initial measurements performed using a wayside TOR-FM system on the Iron Ore Line (IOL – “Malmbanan” in Swedish) could not find any benefits of implementing such systems.

    Trafikverket is considering the implementation of the TOR-FM technology on the IOL. Directly implementing such technology can be inappropriate and expensive, because the reliability of a TOR-FM system has never been assessed for the conditions of the IOL. The IOL is the northernmost railway line in Sweden and is experiencing the problem of RCF, especially on its curves. This railway line is a single track and is mainly utilised by the ore freight trains operated by the Swedish mining company LKAB. The freight trains run by LKAB have an axle load of 30 tonnes, which is the heaviest in Europe. At present LKAB is planning to increase the axle load of their heavy haul trains to 32.5 tonnes, which will increase the RCF and wear issues.

    The present research investigated the effects of TOR-FMs using computer-based simulations, laboratory tests and field tests. The results from all the tests and simulations were used to calculate the life cycle cost of wayside and on-board systems. The simulation results have shown that by reducing the friction, the RCF can be reduced. This reduction in the RCF is greater on narrow curves than on larger curves as the traction forces decrease with an increase in the curve radius. Curves with a radius larger than m are not prone to RCF. The damage index method used in the simulation has also shown that on circular curves with a radius smaller than 300 m, the so-called “magic wear” rate can be achieved. Magic wear means that the wear rate due to normal operation is equal to the crack generation rate. The field results obtained using a handheld tribometer have shown that by using a TOR-FM, both the wear and the friction coefficients can be reduced. The content of the TOR-FM can have a significant effect on the carry distance and, generally, non-drying FMs have a longer carry distance. Excessive use of TOR-FM may cause unacceptably low friction and a high operational cost, and only result in an insignificant increase in the carry distance. In addition, it was also concluded that in the case of the wayside system during extreme winters, the equipment could have maintenance issues and thus a high operational cost. The on-board system is an economical alternative to the wayside system, as it has lower operation and maintenance costs. The results have also shown that snow and ice formation in the winter act as a lubricant. However, further investigations are needed to provide knowledge of the efficiency of such natural lubricants and their retention on the rail. The present research has taken the IOL as a case study, but the results will be applicable all over the world.

     

  • 591.
    Khan, Saad Ahmed
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Effects of Top-Of-Rail Friction-Modifier (TOR-FM) on wear, cracks and friction2016Konferensbidrag (Övrig (populärvetenskap, debatt, mm))
  • 592.
    Khan, Saad Ahmed
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Lundberg, Jan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Stenström, Christer
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Carry distance of top-of-rail friction modifiers2018Ingår i: Proceedings of the Institution of mechanical engineers. Part F, journal of rail and rapid transit, ISSN 0954-4097, E-ISSN 2041-3017, Vol. 232, nr 10, s. 2418-2430Artikel i tidskrift (Refereegranskat)
    Abstract [en]

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

  • 593.
    Khan, Saad Ahmed
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Persson, Ingemar
    AB DEsolver, Östersund, Sweden.
    Lundberg, Jan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Stenström, Christer
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Prediction of the effects of friction control on top-of-rail cracks2018Ingår i: Proceedings of the Institution of mechanical engineers. Part F, journal of rail and rapid transit, ISSN 0954-4097, E-ISSN 2041-3017, Vol. 232, nr 2, s. 484-494Artikel i tidskrift (Refereegranskat)
    Abstract [en]

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

  • 594.
    Khan, Saad Ahmed
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Persson, Ingemar
    AB DEsolver, Östersund.
    Lundberg, Jan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Stenström, Christer
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Prediction of top-of-rail friction control effects on rail RCF suppressed by wear2017Ingår i: Wear, ISSN 0043-1648, E-ISSN 1873-2577, Vol. 380-381, s. 106-114Artikel i tidskrift (Refereegranskat)
    Abstract [en]

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

  • 595.
    Khoshalan, Hasel Amini
    et al.
    Faculty of Mining, Petroleum & Geophysics, Shahrood University of Technology.
    Torabi, Seyed Rahman
    Faculty of Mining, Petroleum & Geophysics, Shahrood University of Technology.
    Hoseinie, Hadi
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Ghodrati, Behzad
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    An introduction to RAM analysis of EPB tunnel boring machine2014Ingår i: Scientific Journal of Pure and Applied Sciences, ISSN 2322-2956, Vol. 3, nr 3, s. 120-127Artikel i tidskrift (Refereegranskat)
  • 596. Khoshouei, Mehrbod
    et al.
    Bagherpour, Raheb
    Ghodrati, Behzad
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Hosseinie, Hadi
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    A Roadmap for Lean Maintenance of Mining Machinery2018Konferensbidrag (Övrig (populärvetenskap, debatt, mm))
    Abstract [en]

    Future mines are automated and highly productive, applying fleet of expensive, complex and high-technology machinery. Considering the high production rate, and high level of safety, the maintenance operation has to satisfy many new requirements targeting the high level of resilience, minimum costs and energy consumption in whole mine production process. Maintenance of mining machinery as a service provider action consists of several internal processes, which are associated by uncertainties, unwanted side-effects, time and resource wastes. To reduce the waste of resources and efforts, the behavior of maintenance process must be predicted as accurately as possible to meet just-in-time (JIT) delivery with accepted level of quality. The lean thinking can efficiently reduce or eliminate the mentioned wastes and losses from the maintenance process of mine. This paper tries to focus on implementation issues, challenges and advantages of lean philosophy application in maintenance management of machinery in current and future advanced mines. For this purpose, the elements of lean maintenance are discussed and analyzed in details. Thus, the practical roadmap and its requirements for implementing the lean concept are presented and discussed.

  • 597.
    Klefsjö, Bengt
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Kvalitet från A till Ö: en resa genom alfabetet med rim och resor2011Bok (Övrig (populärvetenskap, debatt, mm))
  • 598.
    Klefsjö, Bengt
    et al.
    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.
    Goodness-of-fit tests for the power-law process based on the TTT-plot1992Ingår i: IEEE Transactions on Reliability, ISSN 0018-9529, E-ISSN 1558-1721, Vol. 41, nr 4, s. 593-598Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The total-time-on-test plot (TTT-plot) and its theoretical counterpart, the scaled TTT-transform, are reviewed. It is shown how the TTT-plot can be used as a basis for goodness-of-fit tests for the power-law process when data are available from a repairable system. Both a subjective graphical procedure and an analytical test procedure based on the cumulative TTT-statistic are studied (19 refs.)

  • 599.
    Klefsjö, Bengt
    et al.
    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.
    TTT-plotting as a tool when analysing data from a repairable system1992Ingår i: Safety and Reliability '92: [proceedings of the European Safety and Reliability Conference '92 (ESRC '92), the first Pan-European Conference on Safety and Reliability under the auspices of ESA (European Safety and Reliability Association, CEC), held in Copenhagen, Denmark, 10 - 12 June 1992 / [ed] Kurt E. Petersen; Birgitte Rasmussen, London: Elsevier, 1992, s. 819-828Konferensbidrag (Refereegranskat)
    Abstract [en]

    The total time on test plot and its asymptotic counterpart, the scaled TTT-transform, were introduced by Barlow & Campo (1975) for model identification. This paper illustrates a basis for goodness-of-fit tests for the power law process when data from a repairable system are available (17 refs.)

  • 600.
    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.

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