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  • 251.
    Balazs, Peter
    et al.
    Försvarets Forskningsanstalt.
    Hallgren, Mikael
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Concrete Structures.
    Balkar av höghållfast betong belastade med impulslast: Brottmekanisk provning av RILEM-balkar1996Report (Other academic)
  • 252.
    Balazs, Peter
    et al.
    Försvarets Forskningsanstalt.
    Hallgren, Mikael
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Concrete Structures.
    Brotmekanisk provning av Ballistocrete-, Densit-, och Finpartikelbetongbalkar med impulslast och statisk last1997Report (Other academic)
  • 253.
    Balindres, Anecito Reyes
    et al.
    University of Stavanger.
    Kumar, Rupesh
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    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.
    Effects of Arctic Conditions on Human Performance2016In: 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, 657-663 p.Conference paper (Refereed)
    Abstract [en]

    Modern technologies are used to create competitive performance in industry, and highly specialized personnel are often needed to operate and maintain the technology. However, both the technology and the personnel are influenced by the environment in which the technologies are operated. In this paper we study how human performance is influenced by an Arctic environment in conjunction with a remote location. Based on a literature study, we map Arctic factors and study how they affect human performance in remote locations. The results show that operational and maintenance personnel may be significantly affected by the Arctic conditions. If not taken into consideration during the design phase, human and organizational performance may be significantly affected. Examples are discussed in relation to petroleum production in Arctic locations north of Norway

  • 254.
    Banda, Sraj U.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Rock Mass Characterization of the Printzsköld and Fabian Orebodies at the Malmberget Mine2013Report (Other academic)
    Abstract [en]

    Rock mass characterization is usually the first practice required when investigating rock mass responses in mining areas. The ground surface in the Malmberget mine has been affected by subsidence and formation of sinkholes, which have affected many residential areas. As mining progresses to lower levels, caving is expected to occur in the cap rocks of the Printzsköld and Fabian. For optimal planning and operations in the mine, it is therefore necessary to understand the caving mechanism of this area and to investigate the controlling factors in the deformations. This report is a summary of a preliminary rock mass characterization of the Malmberget Mine area, which was aimed at investigating rock mass parameters that will help in the understanding of the caving mechanisms. Diamond core drilling was conducted to obtain rock core for logging. Rock core logging was conducted as well as borehole photography, in which various rock joint orientations were determined. Rock core investigations also revealed zones of weakness due to various phenomena such as weathering, shearing, etc. Laboratory testing of the core samples revealed strength isotropy and high rock mass quality in many areas along the boreholes. Tunnel mapping was carried out only on two production levels of 945 and 970 meters of the Printzsköld orebody. The rock mass has been characterized using the Bieniawski 1989 system of Rock Mass Classification (RMR). The Geological Strength Index was also used to characterize the rock mass in the areas where tunnel mapping took place.

  • 255.
    Barabadi, A.
    et al.
    Iran Itok, Engineering, Procurement and General Contracting.
    Barabady, Javad
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Slope stability analysis using probabilistic method: a case study2008In: MassMin 2008: Proceedings of the 5th International Conference and Exhibition on Mass Mining, Lulea, Sweden 9-11 June 2008 / [ed] Håkan Schunnesson; Erling Nordlund, Luleå: Luleå tekniska universitet, 2008, 887-896 p.Conference paper (Refereed)
  • 256.
    Barabadi, Abbas
    et al.
    University of Tromsø - The Arctic University of Norway.
    Garmabaki, Amir
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics. Islamic Azad University.
    Fuqing, Yuan
    Tromsø University.
    Lu, J.
    University of Tromsø - The Arctic University of Norway.
    Maintainability analysis of equipment using point process models2015In: 2015 IEEE International Conference on Industrial Engineering and Engineering Management (IEEM): Singapore, 6-9 Dec. 2015, Piscataway, NJ: IEEE Communications Society, 2015, 797-801 p., 7385757Conference paper (Refereed)
    Abstract [en]

    The maintenance cost can be reduced significantly by applying the maintainability principle in the design and operation phase. An effective maintainability prediction can help the designer to improve performance and safety of equipment. The analysis of historical repair by an affective statistical approach provides essential information for decision-making regarding the planning of operation and maintenance activities of the plant. However, the literature on field repair data is quite scarce and they are not detailed. This paper will try to provide step by step guideline for field repair data using point process models by a case study.

  • 257.
    Barabadi, Abbas
    et al.
    Tromsø University, Department of Engineering and Safety, UiT The Arctic University of Norway, Tromsø.
    Garmabaki, Amir
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Zaki, Rezgar
    Department of Engineering and Safety, UiT The Arctic University of Norway, Tromsø.
    Designing for performability: An icing risk index for Arctic Offshore2016In: Cold Regions Science and Technology, ISSN 0165-232X, E-ISSN 1872-7441, Vol. 124, 77-86 p.Article in journal (Refereed)
    Abstract [en]

    Ice accretion affects the performability of offshore production facilities in various ways, including repair time and failure rate. It can increase power losses, life cycle costs and safety hazards. There are few studies and limited systematically collected information about the impact of ice accretion on performability and its attributes (reliability, maintainability, quality, safety and sustainability) for Arctic offshore production facilities. This paper will discuss the effects of different types of ice accretion on the performability of Arctic offshore production facilities. Then, to quantify their effect on the performability of offshore production facilities, an icing risk index is developed; its application is then shown by means of a case study.

  • 258.
    Barabadi, Abbas
    et al.
    Tromsø University.
    Ghodrati, Behzad
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Barabady, Javad
    Tromsø University.
    Markeset, Tore
    University of Stavanger.
    Reliability and spare parts estimation considering operational environments: a case study2012Conference paper (Refereed)
    Abstract [en]

    Spare parts provision is a complex problem andrequires an accurate model to analysis all factors that mayaffect the required number of spare parts. The number ofspare parts required can be effectively estimated based onthe reliability performance of the item. The reliabilitycharacteristics of an item are influenced not only by theoperating time, but also by factors such as the operationalenvironment. Therefore, for spare parts provisioning to beeffective, the impact of these influence factors on thereliability performance of the item should be quantified.Hence, the statistical approach selected for reliabilityperformance analysis must be able to handle the effect ofthese factors. One of the important models for reliabilityperformance analysis that takes influence factors intoaccount is the proportional hazard model (PHM), which hasreceived less attention in the field of spare partsprovisioning. In this paper the application of PHM to spareparts provision is discussed and demonstrated by a casestudy.

  • 259.
    Barabady, Javad
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Improvement of system availability using reliability and maintainability analysis2005Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    System reliability, maintainability and availability have assumed great significance in recent years due to a competitive environment and overall operating and production costs. Performance of equipment depends on reliability and availability of the equipment used, operating environment, maintenance efficiency, operation process and technical expertise of operators, etc. When the reliability and availability of system are low, efforts are needed to improve them by reducing the failure rate or increasing the repair rate for each component or subsystem. The aim of this research study is to analyse operating reliability and availability for a system with periodically inspected and maintained components subjected to some maintenance strategy and find some importance measures that show the criticality of the components or subsystems. This analysis has helped to identify the critical and sensitive subsystems or components of the system that need more attention for improvement. In this research study we suggest a methodology for improving the availability of a repairable system. In the methodology, the concept of importance measures must be used to prioritize the components or subsystems for availability improvement processes. Availability importance measures show the criticality of each component based on different points of view such as availability, repair rate, and failure rate of each component. The reliability and availability of repairable systems can be improved by applying appropriate maintenance strategies; therefore a model is developed for selecting the most suitable maintenance strategies on based of analysis of reliability and maintainability characteristic of the operating system. The empirical data of two crushing plants at the Jajarm bauxite mine of Iran are used as a case study for reliability and availability analysis. The study shows that the reliability and maintainability analysis is very useful for deciding maintenance intervals, planning and organizing maintenance. The results show that availability and reliability importance measures can be used as a guideline for managing the efforts for reliability and availability improvement of a system.

  • 260.
    Barabady, Javad
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Production assurance: concept, implementation and improvement2007Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The dynamic business environment is characterized by short-term and long- term uncertainties in the business processes, combined with a short-term focus on meeting customers' and share-holders' requirements. Therefore, making correct decisions in a dynamic business environ-ment is a major challenge for production plant engineers and managers all over the world. Such a situation necessitates the successful application of tools and engineering solutions to minimize the total business risk and reduce uncertainties through assurance of world-class production plant performance, which can ensure that the right level of production can be ob- tained in order to meet customer demands. To meet these challenges, many approaches such as reliability analysis techniques have proved an effective solution during both design and operation of a production plant, and have been implemented by production engineers and managers. The main focus of reliability is on the process of ensuring a reliable product and/or system as well as reducing system uncer- tainty. However, these are not discussing the issues of production availability which are criti-cal for meeting customer requirements and market demands and may increase risk and uncer-tainties in decision-making. However, production assurance (PA) plays a significant role in supporting the decision-making process by production managers and engineers deal with the above mentioned challenges. The main focus of existing research on the area of PA is on the models and methodologies for data analysis and prediction of future system performance. Fur-thermore, existing models and methodologies supporting PA analysis and management have been primarily developed for the planning phases, specifically for the petroleum sector, but have not yet been sufficiently developed for general use. In many cases, the engineers and managers may face many problems in the process of implementing and executing the PA con-cept. The purpose of this research is to study, analyze and evaluate the application and implementa-tion of Production Assurance Programs (PAP) in production plants, and find some importance measures that show the criticality of the components or subsystems. To fulfill the stated pur- pose, an explorative literature study combined with a case study of a process plant has been performed. Various examples and data from the oil and gas industry are also used to support the thesis. In this study, firstly the concept of production assurance is discussed and Overall Production Assurance Effectiveness (OPaE) is suggested as a developed metrics for measuring the per-formance of a production plant which is considered internal effectiveness of production plant as well as external effectiveness as it considered customer requirement and demand. This thesis present and discusses a methodology that facilitates implementation of PAPs in a production plant. Such a methodology would support production engineers and managers in reducing or eliminating uncertainties and risks in their day to day operation and maintenance decisions. In this research study, some availability importance measures are defined. Thereafter, it a methodology is suggested to improve the production assurance effectiveness through im-provement of reliability, maintainability, and availability of production plant. In the method-ology, the concept of importance measures is used to prioritize the components or subsystems. This analysis of importance measures has helped to identify the critical and sensitive subsys-tems or components that need more attention for improvement. The research study shows that in order to measure the performance of a production plant, the PA provides a more comprehensive measure of a production plant's real performance com-pared to system availability performance as the production assurance provides information about the production plant's delivery capacity, production rate and ability to deliver according to design or customer demands. The study also indicates that availability importance measures can serve as a guideline for developing a strategy for improvement of production assurance.

  • 261.
    Barabady, Javad
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Reliability and maintainability analysis of crushing plants in Jajarm bauxite mine of Iran2005In: 2005 proceedings: Annual Reliability and Maintainability Symposium, International Symposium on Product Quality and Integrity : Alexandria, Virginia, USA, 2005, January 24 - 27, Piscataway, NJ: IEEE Communications Society, 2005, 109-115 p.Conference paper (Refereed)
    Abstract [en]

    Reliability is an important consideration in the planning, design and operation of engineering systems. As the size and complexity of mining equipment continue to increase, the implications of equipment failure become ever more critical. An unplanned failure can result in significantly higher repair costs than a planned maintenance or repair. Of even more importance is the loss of production associated with larger equipment failures. One method to mitigate the impact of failures is to improve the reliability of the equipment. Reliability is a performance indicator of overall equipment condition. A first step in reliability improvement is collection and analysis of the appropriate data.This paper presents a case study describing reliability analysis of crushing plants in Jajarm bauxite mine. In this study crushing plants are divided into seven subsystems. Reliability analysis has been done for each subsystem by using failures data. The parameters of some idealized probability distributions, such as Weibull, Exponential, Lognormal distributions, have been estimated by using ReliaSoft's Weibull++ 6 software. An investigation has also been made to determine which of these distributions provide the best fit for characterizing the failure pattern of the two crushing plants and their subsystems. Some aspects of system failure behavior are analyzed briefly for ongoing machine improvement. Reliability of both crushing plants and its subsystems has been estimated at different mission times with their best fit distribution. Analysis of the total downtime, breakdown frequency, reliability, and maintainability characteristics of different subsystems shows that the reliability of crushing plant 1 and crushing plant 2 after 10 hour reduce to about 64% and 35% respectively. The study shows that reliability and maintainability analysis is very useful for deciding maintenance intervals. It is also useful for planning and organizing maintenance.

  • 262.
    Barabady, Javad
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Aven, T.
    University of Stavanger.
    A methodology for the implementation of production assurance programmes in production plants2008In: Journal of Risk and Reliability, ISSN 1748-006X, E-ISSN 1748-0078, Vol. 222, no 3, 283-290 p.Article in journal (Refereed)
    Abstract [en]

    There is an increased use of production assurance programmes in various industries, especially in the petroleum sector. The programme describes the production assurance activities necessary to fulfil the objectives, how they will be carried out, by whom, and when. The activities provide input to decisions regarding concept, design, manufacturing, construction, installation, operation, and maintenance. However, production assurance programmes have not yet been sufficiently developed for general use. It is a challenge to implement and apply such programmes in a practical setting. There is a lack of implementation guidelines. The purpose of the current paper is to meet these challenges; the paper describes and discusses a methodology that facilitates implementation of production assurance programmes in a production plant. 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 other industries.

  • 263.
    Barabady, Javad
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Aven, Terje
    University of Stavanger.
    Implementation of production availability programmes in engineering projects2007In: Risk, Reliability and Societal Safety: proceedings of the European Safety and Reliability Conference 2007 (ESREL 2007), Stavanger, Norway, 25 - 27 June 2007 / [ed] Terje Aven; Jan Erik Vinnem, London: Taylor and Francis Group , 2007, 487-494 p.Conference paper (Refereed)
    Abstract [en]

    The aim of this paper is to present and discuss a methodology for implementing production availability programmes in engineering projects. The programmes are to ensure that the project goals will be met. The programme describes the production availability activities necessary to fulfil the objectives, how they will be carried out, by whom and when. The activities provide input to decisions regarding concept, design, manufacturing, construction, installation, operation and maintenance. The proposed methodology consists of three primary tasks and decisions. The three primary tasks are i) establish production availability requirements; ii) provide input to the design process and to operations; and iii) monitor production availability achievement and publish periodic report. Establishing the proposed methodology will help ensure that the project has a cohesive and cost-effective production availability programme, reflecting a production availability process and activities defined in view of the actual needs, available personnel resources, budget framework, interfaces, milestones, and access to data and general information.

  • 264. Barabady, Javad
    et al.
    Kumar, Uday
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    A method for managing the availability improvement efforts2006In: Engineering Asset Management: Proceedings of the First World Congress on Engineering Asset Management (WCEAM), London: Encyclopedia of Global Archaeology/Springer Verlag, 2006, 445-451 p.Conference paper (Refereed)
    Abstract [en]

    Availability is an important characteristic of a repairable system. When the availability of system is low, efforts are needed to improve it. Any improvement in the availability of a system is associated with the requirement of additional effort and cost. Therefore, it is essential to use methods or techniques for availability allocation amongst various components/subsystems of a system with the minimum effort and cost. The concept of importance measures could be used to prioritize the components or subsystems for the availability improvement process. The study shows, it is useful to obtain the availability importance measures value of each component in the system prior to deploying resources towards improving the specific components. With the assistance of importance measures one can identify the components/subsystems that merit additional research and development to improve their availabilities, so that the greatest gain is achieved in the system availability. Each component should be assigned a value and the component with a greater value will have a greater influence on the availability of the system. Generally, the importance of components should be used during the design or evaluation of systems to determine which components or subsystems have the greatest importance for the availability of the system.

  • 265. Barabady, Javad
    et al.
    Kumar, Uday
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Availability alocation through importance measures2007In: International Journal of Quality & Reliability Management, ISSN 0265-671X, E-ISSN 1758-6682, Vol. 24, no 6, 643-657 p.Article in journal (Refereed)
    Abstract [en]

    Purpose - To define availability importance measures in order to calculate the criticality of each component or subsystem from availability point of view and also to demonstrate the application of such importance measures for achieving optimal resource allocation to arrive at the best possible availability. Design/methodology/approach - In this study the availability importance measures of a component are defined as a partial derivative of the system availability with respect to the component availability, failure rate, and repair rate. Analyses of these measures for a crushing plant are performed and the results are presented. Furthermore, a methodology aimed at improving the availability of a system using the concept of importance measures is identified and demonstrated by use of a numerical example.Findings - The availability importance measure of a component/subsystem is an index which shows how far an individual component contributes to the overall system availability. The research study indicates that the availability importance measures could be applied in developing a strategy for availability improvement. The subsystem/component with the largest value of importance measure has the greatest effect on the system availability. Research limitations/implications -The result of availability improvement strategy is demonstrated using only a hypothetical example.Practical implications - Using of availability importance measures will help managers and engineers to identify weaknesses and indicate modifications which will improve the system availability.Originality/value - This paper presents the concept of availability importance measure for a component/subsystem. It also introduces some availability importance measures based on failure rate, mean time between failures (MTBF), and repair rate/mean time to repair (MTTR) of a component /subsystem. The concept of importance measures are used to prioritize the components or subsystems for the availability improvement process.

  • 266. Barabady, Javad
    et al.
    Kumar, Uday
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Maintenance schedule by using reliability analysis: a case study at Jajarm bauxite mine of Iran2005In: 20th World Mining Congress, November 7-11, 2005, Tehran, Iran: mining and sustainable development, Teheran: Geological Survey of Iran , 2005Conference paper (Refereed)
    Abstract [en]

    Maintenance represents a significant proportion of the overall operating costs in the mining industry. The optimal maintenance scheduling can reduce the cost of maintenance and extend equipment lifetime. Since the cost of maintenance is very high, therefore, mining industry need to reduce maintenance cost reasonably meanwhile keeping system reliability and availability high. Despite the large cost of maintenance, mine management has only given passing attention to the optimization of the maintenance process. Performance of a mine production system depends on reliability and effectiveness of maintenance strategy of the equipment. An unplanned failure can result in significantly higher repair costs than a planned maintenance or repair. Of even more important is the loss of production associated with larger equipment failures. This paper is divided into two parts. First part introduces a methodology for optimal maintenance scheduling using reliability analysis and maintenance data analysis, in the form of time between failure and time to repair distributions. In the second part we present a case study from Jajarm bauxite mine of Iran to illustrate the effectiveness of the maintenance scheduling model.

  • 267. Barabady, Javad
    et al.
    Kumar, Uday
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Production assurance concept for a mine production system2008In: Mine planning and equipment selection: proceedings of seventeenth International Symposium on Mine Planning and Equipment Selection (MPES 2008), held in Beijing, China October 20-22, 2008 / [ed] Raj K Singhal, Bejing: Conference Division, Metallurgical Council of CCPIT , 2008, 379-387 p.Conference paper (Refereed)
  • 268. Barabady, Javad
    et al.
    Kumar, Uday
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Reliability analysis of mining equipment: a case study of a crushing plant at Jajarm Bauxite Mine in Iran2008In: Reliability Engineering & System Safety, ISSN 0951-8320, E-ISSN 1879-0836, Vol. 93, no 4, 647-653 p.Article in journal (Refereed)
    Abstract [en]

    The performance of mining machines depends on the reliability of the equipment used, the operating environment, the maintenance efficiency, the operation process, the technical expertise of the miners, etc. As the size and complexity of mining equipments continue to increase, the implications of equipment failure become ever more critical. Therefore, reliability analysis is required to identify the bottlenecks in the system and to find the components or subsystems with low reliability for a given designed performance. It is important to select a suitable method for data collection as well as for reliability analysis. This paper presents a case study describing reliability and availability analysis of the crushing plant number 3 at Jajarm Bauxite Mine in Iran. In this study, the crushing plant number 3 is divided into six subsystems. The parameters of some probability distributions, such as Weibull, Exponential, and Lognormal distributions have been estimated by using ReliaSoft's Weibull++6 software. The results of the analysis show that the conveyer subsystem and secondary screen subsystem are critical from a reliability point of view, and the secondary crusher subsystem and conveyer subsystem are critical from an availability point of view. The study also shows that the reliability analysis is very useful for deciding maintenance intervals.

  • 269. Barabady, Javad
    et al.
    Kumar, Uday
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Reliability charecteristic based maintenance scheduling: a case study of a crushing plant2007In: International Journal of Pedagogy, Innovation and New Technologies, ISSN 0973-1318, E-ISSN 2392-0092, Vol. 3, no 3, 319-328 p.Article in journal (Refereed)
    Abstract [en]

    The cost of maintenance is too high in mining industry to ignore. This is mainly due to poor understanding of the maintenance process which is greatly influenced by the reliability characteristics of the operating system. The paper introduces an approach for maintenance scheduling of a mining system based on reliability analysis which is divided into two parts. The first part introduces a methodology for optimal maintenance scheduling based on analysis of maintenance data in the form of time-between-failure and time-to-repair distributions. In the second part, we present a case study from Jajarm Bauxite Mine in Iran to illustrate the applicability of the maintenance scheduling model.

  • 270. Barabady, Javad
    et al.
    Markeset, T.
    Kumar, Uday
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Overall production assurance effectiveness2008In: Proceedings of the 3rd World Congress on Engineering Asset Management and Intelligent Maintenance Systems: WCEAM-IMS 2008 : Engineering Asset Management - A Foundation for Sustainable Development, 27 - 30 October 2008, Beijing, China, 2008, 202-206 p.Conference paper (Refereed)
  • 271. Barabady, Javad
    et al.
    Markeset, Tore
    University of Stavanger.
    Kumar, Uday
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    A framework for improvement of production plant performance using production assurance programs2010In: International Journal of Systems Assurance Engineering and Management, ISSN 0975-6809, E-ISSN 0976-4348, Vol. 1, no 1, 59-65 p.Article in journal (Refereed)
    Abstract [en]

    The main objective of a production assurance program (PAP) for a production plant is to ensure that the planned production capacity is achieved. The assurance programs describe the activities necessary to fulfil the objectives, how they will be carried out, by whom, and when. These activities also provide input to decisions-making regarding design, manufacturing, construction, installation, operation, and maintenance of plants. It is a challenge to manage and improve production assurance. The aim of this paper is to present and discuss a methodology for improvement of production assurance performance through PAP, organized into four steps, namely data collection and information management, modeling and data analysis, generation of improvement alternatives and evaluation and decision-making.

  • 272. Barabady, Javad
    et al.
    Markeset, Tore
    University of Stavanger.
    Kumar, Uday
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Improvement of production plant performance using production assurance programs2007Conference paper (Refereed)
    Abstract [en]

    There is an increased use of production assurance programmes in Oil and Gas industries. The programme describes the production assurance activities necessary to fulfill the objectives, how they will be carried out, by whom and when. The activities provide input to decisions regarding concept, design, manufacturing, construction, installation, operation and maintenance. It is a challenge to manage and improve production assurance. The aim of this paper is to present and discuss a methodology for improvement of production assurance performance. The proposed methodology consists of four steps. These steps are i) data collection and information management; ii) modeling and data analysis; and iii) generate improvement alternatives; and iv) evaluation alternatives and decision making.

  • 273. Barabady, Javad
    et al.
    Markeset, Tore
    University of Stavanger.
    Kumar, Uday
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Review and discussion of production assurance program2010In: International Journal of Quality & Reliability Management, ISSN 0265-671X, E-ISSN 1758-6682, Vol. 27, no 6, 702-720 p.Article in journal (Refereed)
    Abstract [en]

    Purpose - The purpose of this paper is to review, discuss and further develop the production assurance (PA) concept; and to define and describe a typical production assurance program (PAP) and its elements. Design/methodology/approach - An explorative literature study covering PA and dependability concept was carried out on contemporary literature. During the course of the study, meetings and discussions with a number of experts in Sweden and Norway were performed. Different types of data and examples from the oil and gas industries are used to illustrate and support the discussions. Findings - This paper indicates that the concept of PA helps the decision maker to estimate whether a production plant is able to meet customer requirements, as it provides information about the production plant's delivery capacity, production rate and ability to deliver according to design or customer demands. PAP can provide a basis for effective production control. Research limitations/implications - The material analysed was mainly related to the oil and gas industry. However, the findings and discussion can be transferred to other areas of application, such as mine production plants and chemical process plants. Practical implications - A PAP is a valuable tool for production plant managers and engineers, not only for documenting a production plant's performance, but also for providing decision support for the development and optimization of the production plant to improve the plant's performance and reduce risk and uncertainties. Originality/value - In this paper the concept of dependability is extended to include capacity performance and customer requirements or market demand, which provides a measure for delivery assurance or plant production performance in relation to customer requirements. This paper also develops a generic PAP to achieve a high level of delivery assurance.

  • 274.
    Barba, Tomas Villegas
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Nordlund, Erling
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Numerical analyses of the hangingwall failure due to sublevel caving: study case2013In: International Journal of Mining and Mineral Engineering, ISSN 1754-890X, E-ISSN 1754-8918, Vol. 4, no 3, 201-223 p.Article in journal (Refereed)
    Abstract [en]

    The sublevel caving used in Kiirunavaara mine induces failure and subsidence of the hangingwall. Two sections of the mine were studied by means of numerical analyses. Numerical models were developed using finite element and discrete element codes. The former was applied to calculate the location of new failure surfaces in the hangingwall and to estimate the break angle when mining advances downwards. The latter was used to analyse the displacement path of the caved rock during draw and to determine its effect on the stability of the hangingwall and footwall. The models were calibrated using displacement monitoring data. The finite element analyses indicated that the break angle is almost constant for deeper mining levels but may change if the geometry of the orebody changes. The discrete element model showed the formation of a stationary zone along the footwall that reduces the magnitude of the shear forces during draw, increasing its stability.

  • 275.
    Barbens, P.T.
    et al.
    Aalto University, Espoo.
    Uotinen, L.
    Aalto University, Espoo.
    Toivanen, T.L.
    Aalto University, Espoo.
    Edelbro, Catrin
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Improving teaching methods of rock mass classification parameters2014In: Rock Engineering and Rock Mechanics: Structures in and on Rock Masses / [ed] R. Alejano, CRC Press, 2014, 451-455 p.Conference paper (Refereed)
    Abstract [en]

    To promote knowledge in rock mass classification methods, a short course was arranged in research tunnels beneath Aalto University in Espoo, Finland. After the course, the participants had a short (45+45 min) hands-on tunnel mapping exercise where they logged 12 core boxes and one 10 m tunnel wall section. The attendees were asked to submit their mapping sheets for a post-study. The objective of the study was to discover which parameters show most scatter and to develop suggestions to improve the teaching methods. Statistical analysis of the data was carried out and RQD parameter was analyzed in more detail as it had the largest amount of data. Insufficient logging time may be one of the causes for the lack of data for other parameters. Significant scatter was observed in the RQD parameter and the comparison between inexperienced and experienced mappers show no clear difference. The teaching arrangements and problems faced are stated and recommendations on how to improve the situation are presented

  • 276.
    Barrefjord, Madelene
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management.
    Delin, Hanne-Marie
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management.
    Förrättningslantmätarens hantering av stiftelser utifrån Kammarkollegiets och tillsynsmyndigheternas prövningar2013Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Huvudsyftet med studien var att utreda och klargöra hur förrättningslantmätaren bör handla när en stiftelse blir sakägare i en lantmäteriförrättning och hur stiftelsen ska behandlas utifrån förrättningslantmätarens undersökningsplikt. Studien hade även två delsyften där det första skulle beskriva och analysera hur stiftelsers föreskrifter kan ändras, medan de andra skulle utreda hur tillsynsmyndigheternas registrering av stiftelser genomförs. Förrättningslantmätare är en yrkesroll inom lantmäterimyndigheten och har till uppgift att handlägga samt besluta i fastighetsbildnings-ärenden. Lantmäterimyndigheten är den myndighet som har till uppgift att ansvara för att en effektiv och rättssäker fastighetsindelning genomförs. En stiftelse är en typ av juridisk person som bildas av en eller flera personer för att verka för ett bestämt ändamål. Stiftelsen ska förvalta en ekonomisk förmögenhet som har avsatts för ett bestämt ändamål, där förvaltningen ska ske över en längre tid. Förmögenheten kan bestå av fast egendom i form av fastigheter.

    Metoder som använts för att besvara studiens syften och forskningsfrågor var en litteraturstudie, en intervjustudie och en fallstudie. Litteraturstudien granskade tidigare forskning inom ämnes-området, lagstiftningen och facklitteratur för att ge en vetenskaplig grund. Intervjustudien genom-fördes för att få en grundlig förståelse för hur tillsynsmyndigheternas och Kammarkollegiets prövningar går till vid ändring av stiftelsers föreskrifter. Fallstudien granskade och jämförde tillsynsmyndigheternas och Kammarkollegiets prövningar vid ändring av stiftelsers föreskrifter, men fallstudien jämförde även vilka dokument tillsynsmyndigheterna kräver in av en stiftelse när den ska registreras. Intervjuer gjordes i fallstudien med samtliga tillsynsmyndigheter för att samla information om hur deras prövningar går till när stiftelser ska registreras i stiftelseregistren.

    Resultatet av litteraturstudien bestod av beskrivningar av förrättningslantmätarens yrkesroll, fastighets-, ägande- och stiftelsebegreppet. Resultatet av intervjustudien visade att de intervjuade tillsynsmyndigheterna och Kammarkollegiet har olika grundliga prövningar vid ändring av stiftelsers föreskrifter. Detta visade även fallstudien samt att tillsynsmyndigheternas prövningar skiljer sig åt vid registrering av en stiftelse. Slutsatsen beskriver hur förrättningslantmätaren ska handla när en stiftelse blir sakägare i en lantmäteriförrättning och hur stiftelsen ska behandlas utifrån förrättningslantmätarens undersökningsplikt. Två mallar finns i slutsatsen som innehåller riktlinjer för hur en kontroll av stiftelsens föreskrifter kan göras för att vara säker på att fastighets-bildningen inte strider mot stiftelsens föreskrifter.

  • 277. Barton, Nick
    et al.
    Stephansson, OveLuleå tekniska universitet.
    Rock joints: proceedings of the International Symposium on Rock Joints, Loen / Norway / 4-6 June 19901990Collection (editor) (Other academic)
  • 278. Basu, A.
    et al.
    Kumar, Uday
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Business case for sustainable performance: management at the project level leading to project sustainability2002In: MTM - 2002 Proceedings: International Seminar on Mining, Technology, and Management for Business Excellence, New Delhi, November 2002, Hyderabad: Mining Engineers' Association of India , 2002Conference paper (Refereed)
  • 279.
    Basu, Arun J.
    et al.
    Department of Earth Science and Engineering, Imperial College London.
    Kumar, Uday
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Innovation and technology driven sustainability performance management framework (ITSPM) for the mining and minerals sector2004In: International Journal of Mining, Reclamation and Environment, ISSN 1748-0930, E-ISSN 1748-0949, Vol. 18, no 2, 135-149 p.Article in journal (Refereed)
    Abstract [en]

    Sustainable development (SD) has been defined as the development that lasts while also contributing to a better quality of life for everyone involved (stakeholders). This is a global concept that integrates and balances the social, economic, and environment factors. A major component of implementing the SD concepts is its governance. Activities such as training and developing standards of measuring SD (indicators) are of critical importance for control and proper implementation of SD for the mining and minerals industry in a global scale maintaining the local constraints. Achieving project sustainability satisfies a local sustainability goal, which in turn would contribute to the corporate sustainability, and then the global sustainability of a country or a region. A sustainable development framework in the form of sustainable performance management (SPM) is addressed. Implementation of SPM requires a set of indicators for measuring, monitoring, and reporting the progress. This paper emphasises the need for innovation and technology driven sustainable performance management (ITSPM) framework, encapsulated by a Multi-Stakeholder Process (MSP) for performance management and developing the relevant performance indicators.

  • 280.
    Batsos, Epameinondas
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, Geodesy and Geoinformatics.
    Rabbi, Atta
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, Geodesy and Geoinformatics.
    Clustering and cartographic simplification of point data set2012Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
  • 281. Benda, Sten
    EMC undersökning i Kiruna 2003-06-23--272004Report (Other academic)
    Abstract [sv]

    Många tågförseningar förorsakas av elektromagnetiska störningar t.ex. åsknedslag och signaler som slår om till rött av okänd anledning. Med detta som grund enades arbetsgrupp TURSAM (Tillämpat underhåll i samverkan) på rekommendation av Banverket Projektering Luleå kontoret, om att anlita EMCES Sten Benda att försöka identifiera bakomliggande orsak till dessa störningar. Sten Benda utförde tillsammans med Banverket Norra Banregionen, personal från EISLAB (LTU) underökningar och mätningar på anläggningar: Syfte var att hitta de bakomliggande orsakerna till elektromagnetiska störningar i järnvägsmiljö. Målsättning för den här undersökningen är att fastställa om elektromagnetiska störningar kan orsaka problem som kan påverka järnvägsdrift. Sten Bendas undersökning och rapport visar på ett antal allvarliga fel bl.a. Grundläggande fel i överordnade föreskrifter, missförstånd angående hur skärmning av elektromagnetiska fält skall utföras vilket medför att nya anläggningar byggs och monteras så att EMC-skyddet helt förstörs. Felaktig terminologi användes, bl a förväxlas begreppen låg-ohmig och låg-impediv. Stora dyra kurar (30 tkr/st) för skärmning perforeras med hål, med rätt installation kan billigare kurar (5 tkr/st) användas. Slutbesiktningen släpper igenom för många byggfel och dokumentationen i anläggningarna stämmer inte överens med verkligt montage. Elsäkerheten bevakas inte.

  • 282.
    Bengtsson, Jonas
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, Geodesy and Satellite Positioning.
    Grönkvist, Mikael
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, Geodesy and Satellite Positioning.
    Performing Geographic Information System Analyses on Building Information Management Models2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    As the usage of both BIM (Building Information Modelling) and 3D-GIS (Three-Dimensional Geographic Information Systems) has increased within the field of urban development and construction, so has the interest in connecting these two tools.  One possibility of integration is the potential of visualising BIM models together with other spatial data in 3D. Another is to be able to perform spatial 3D analyses on the models. Both of these can be achieved through use of GIS software.

    This study explores how integration of BIM and GIS could look. The goal was to perform typical GIS analyses in 3D on BIM models. Previous research points towards some success within the field through use of the indicated standard format for each tool – IFC (Industry Foundation Classes) for BIM and CityGML (City Geographic Markup Language) for GIS. Transformation between the formats took place through use of the BIM software Revit, the transformation tool FME and the GIS software ArcGIS. A couple of reviewed applications of GIS analyses were chosen for testing on the converted models – indoor network analysis, visibility analysis and spatial analysis for 3D buildings.

    The input data in the study was several BIM models, both models created for real-life usage and others that only function as sample data within the different software. From the results of the practical work it can be concluded that a simple, automated and full-scale integration does not seem to be within reach quite yet. Most transformations between IFC and CityGML failed to some extent, especially the more detailed and complex ones. In some test cases, the file could not be imported into ArcGIS and in others geometries were missing or existing even though they should not. There were also examples where geometries had been moved during the process. As a consequence of these problems, most analyses failed or did not give meaningful results. A few of the original analyses did give positive results. Combining (flawed) CityGML models with other spatial data for visualisation purposes worked rather well. Both the shadow volume and sightline analyses did also get reasonable results which indicates that there might be a future for those applications.

    The obstacles for a full-scale integration identified during the work were divided into four different categories. The first is BIM usage and routines where created models need to be of high quality if the final results are to be correct. The second are problems concerning the level of detail, especially the lack of common definitions for the amount of details and information. The third category concerns the connection between local and global coordinate systems where a solution in form of updates to IFC might already be in place. The fourth, and largest, category contains those surrounding the different formats and software used. Here, focus should lie on the transformation between IFC and CityGML.

    There are plenty of possible, future, work concerning these different problems. There is also potential in developing own tools for integration or performing different analyses than those chosen for this thesis.

  • 283.
    Bengtsson, Magnus
    et al.
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Nilsson, Jens
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Klimatsimulering av ett kyrktorn uppfört i sten2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Detta examensarbete syftar till att utreda klimatsimuleringsprogrammen IDA-ICE och WUFI, hur dessa program kan komplettera varandra och användas till simulering av kyrktorn som blivit byggda i sten. IDA-ICE har av tidigare utredningar klargjort att detta program inte redovisa fuktlagring i konstruktioner vilket WUFI gör, därav valet till dessa program. Klimatsimuleringarna utförs i Nässjö gamla kyrkas torn som är byggt av stenblock som sammanfogats med kalkbruk.

    Utredningen görs med hjälp av klimatloggar som mäter temperatur och relativ fuktighet. Dessa mätinstrument placeras ut i Nässjö gamla kyrkas torn för mätning. Värdena för klimatloggarna jämförs med simuleringarnas värden från IDA-ICE och WUFI.

    Klimatsimuleringarna visar sig inte ge samma värden av temperatur eller relativ fuktighet gentemot klimatloggarnas uppmätta värden. Klimatdatan i IDA-ICE skiljer sig mycket från verkligheten vilket bland annat påverkar resultatet. WUFI simulerar endimensionella punkter för konstruktioner vilket innebär att uppbyggnaden av ytterväggarna i programmet inte ger en rättvis bild mot verkligheten, vilket också påverkar resultatet. Resultatet ger därför en bristfällighet till användning av dessa simuleringsprogram, för utredning av klimatet i kyrktorn som är byggda i sten. Det är istället säkrare att använda klimatloggar vid utredningar av klimat, för denna typ av byggnad, då dessa, rätt kalibrerade är tillförlitliga.

  • 284.
    Berg, Marianne
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management.
    Berglund, Helene
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management.
    Utvärdering av möjligheten att använda UAS vid gränsmätning i skogsmiljö2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Real properties in Dalarna often consist of small lots of forest or agriculture. These lots are often elongated and consequently impractical, therefore the Swedish mapping, cadastral and land registration authority performs comprising land consolidations. These are to swap land between the owners of the properties, in order to form appropriate lots, for purpose of, inter alia, promoting investment and development opportunities in the region. In order to establish a map, a decision basis, for the valuation of the lot, the claimed proprietary right has to be surveyed. The work is performed with NRTK (network-RTK) or total station, and the maximum allowed planar deviation is 0.50 m (base level requirement). The purpose of this study was to examine whether there is a possibility of using Unmanned Aircraft Systems (UAS) when claimed property boundaries are going to be surveyed. UAS is a system consisting of an unmanned aerial vehicle, a digital camera, a Global Positioning System (GPS) receiver, an Inertial Navigation System (INS) and a control station.

    In a delimitated area of about 24 ha in Norra Åbyggeby, north of Gävle, black and white and white markers, with the size of 0.40x0.40 m, were positioned in the terrain and then surveyed as ground control points or boundary points with network RTK. Mean planimetric coordinates have been calculated for the control points, which have been used as reference coordinates. These have been compared with the coordinates measured in an orthophotomosaic produced from flights with UAS at an altitude of 100 and 180 m. To get a further comparison, the coordinates were determined by a block adjustment in the software PhotoScan from Agisoft. The object identification of the markers, placed in different environments, and from different altitudes has been studied.

    The digitalization in the orthophotomosaic resulted in a Root Mean Square error (RMS-value) of 0.083 m at an altitude of 100 m and a value of 0.049 m at an altitude of 180 m. Corresponding RMS values were 0.071 m at an altitude of 100 m and 0.077 m at an altitude of 180 m when computed in PhotoScan. F-test has been calculated using the four RMS values, the result of the F-test showed that coordinates obtained in an orthophotomosaic, in ArcMap, are equivalent to coordinates obtained by block adjustment, in PhotoScan. The F-test also showed that the coordinates are equivalent from altitudes 100 and 180 m by block adjustment, but they are not equivalent when they are obtained in an orthophotomosaic from altitudes 100 and 180 m. If we disregard the systematic error at three of the points (orthophotomosaic 100 m) the F-test did not show any statistically significant difference between the two altitudes.

    All deviations were below the base level requirement. The largest planar deviation was 0.181 m at an altitude of 100 m and 0.083 m at an altitude of 180 m. Corresponding values for PhotoScan were 0.155 m and 0.148 m. How dense the forest was where the marker was placed and the impact of the sun, in terms of shadows and brightness, have affected the composition of the mosaic, and consequently the deviations. UAS can be used for surveying of claimed property boundaries, but there is no guarantee that all signalized boundary points can be surveyed directly in the orthophotomosaic. One recommendation is to use a less accurate method for the measurement of the ground control points (needed for the georeferencing of the point cloud/orthophotomosaic) than the method used in this thesis. The higher altitude is preferable because the time requirement of the flight will be shorter, and a smaller number of aerial photos need to be processed. Choose the method that the user is used to, manual digitizing in an orthophotomosaic or automatic calculation in a block adjustment.

  • 285.
    Berg, Susanne
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering.
    Uppföljning efter PCB sanering: -En studie av kommuners uppföljande verksamhet efter PCB sanering i byggnad2017Independent thesis Basic level (university diploma), 5 credits / 7,5 HE creditsStudent thesis
  • 286.
    Berg, Sven
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Mechanics of Solid Materials.
    Jungmar, Ulf
    Bodycote Materials Testing AB, Linköping.
    Lundberg, Jan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Vähäoja, Pekka
    Department of Mechanical Engineering, University of Oulu.
    Investigation of the measurement precision of oil analysis instruments, using fully formulated oils: Part 1: Spectroscopic instruments2011In: Industrial Lubrication and Tribology, ISSN 0036-8792, E-ISSN 1758-5775, Vol. 63, no 6, 404-411 p.Article in journal (Refereed)
    Abstract [en]

    Purpose - The aim of this study is to determine the variation of the different oil analysis instruments in terms of standard deviation and CV-values, when measuring samples of fully formulated hydraulic and gear oils taken from working systems. Design/methodology/approach - In this investigation, two different spectrometric techniques, inductively coupled plasma-optical emission spectrometers (ICP-OES) and rotating disk electrode-optical emission spectrometers (RDE-OES), have been studied to determine the instruments' precision of measurement and ability to measure the absolute level of contamination. The study was based on a series of measurements using artificial contamination mixed with oil. Findings - The ICP has better precision of measurement of the two instruments, but cannot predict the absolute values of contamination when oil samples are only treated by organic solvent dilution if the samples include large or dense particles. It is therefore not too good, with the sample pre-treatment method used, at detecting wear processes that produce dense/large particles, such as pitting failure. For instance, microwave-assisted acid digestion could be used for sample pre-treating to obtain accurate results in that case. It should, however, be able to detect wear mechanisms that produce small particles such as abrasive wear in any case. The ICP has a repeatability value of r=3 percent and a reproducibility value of R=12 percent for contamination levels of between 50 and 400 ppm and r=0.6 and R=2 ppm, respectively, at values below 50 ppm. The RDE cannot predict the absolute value of contamination if this includes large or dense particles if proper sample pre-treatment is not used. It is therefore not good at detecting wear mechanisms that produces dense/large particles (if the oil samples are not pre-treated properly) such as pitting but should be able to detect abrasive wear and similar processes that produce small particles in any case. The RDE's precision of measurement is not as good as the ICP, with a reproducibility variation of R=r=25 percent for contamination levels between 20 and 500 ppm and R=r=6 ppm for contamination level below 20 ppm. Research limitations/implications - Only the effects from lubricating oils are studied. Practical implications - This study will significantly increase the industrial knowledge concerning measurement precision in particle contamination measurement systems. Originality/value - No similar study is found

  • 287.
    Berg, Sven
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Mechanics of Solid Materials.
    Jungmar, Ulf
    Bodycote Materials Testing AB, Linköping.
    Lundberg, Jan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Vähäoja, Pekka
    Department of Mechanical Engineering, University of Oulu.
    Investigation of the measurement precision of oil analysis instruments, using fully formulated oils: Part 2: Contamination-measuring instruments2011In: Industrial Lubrication and Tribology, ISSN 0036-8792, E-ISSN 1758-5775, Vol. 63, no 6, 412-419 p.Article in journal (Refereed)
    Abstract [en]

    Purpose - The aim of this study is to determine the variation of the different oil analysis instruments in terms of standard deviation and CV-values, when measuring samples of fully formulated hydraulic and gear oils taken from working systems. Design/methodology/approach - In this investigation two different spectrometric techniques, ICP-OES and RDE-OES, have been studied to determine the instruments' precision of measurement and ability to measure the absolute level of contamination. Findings - The ICP has better precision of measurement of the two instruments, but cannot predict the absolute values of contamination when oil samples are only treated by organic solvent dilution if the samples include large or dense particles. It is therefore not too good, with the sample pre-treatment method used, at detecting wear processes that produce dense/large particles, such as pitting failure. For instance, microwave-assisted acid digestion could be used for sample pre-treating to obtain accurate results in that case. It should, however, be able to detect wear mechanisms that produce small particles such as abrasive wear in any case: the ICP has a repeatability value of ITr/IT=3 per cent and a reproducibility value of ITR/IT=12 per cent for contamination levels of between 50-400 PPM and ITr/IT=0.6 PPM and ITR/IT=2 PPM, respectively, at values below 50 PPM; the RDE cannot predict the absolute value of contamination if this includes large or dense particles if proper sample pre-treatment is not used. It is therefore not good at detecting wear mechanisms that produce dense/large particles (if the oil samples are not pre-treated properly) such as pitting but should be able to detect abrasive wear and similar processes that produce small particles in any case; the RDE's precision of measurement is not as good as the ICP, with a reproducibility variation of ITR/IT=ITr/IT=25 per cent for contamination levels between 20-500 PPM and ITR/IT=ITr/IT=6 PPM for contamination level below 20 PPM. Research limitations/implications - Measuring only on fully formulated oils from hydraulic and gear systems. Practical implications - The study will be of significant support regarding industrial interpretation of measurement results from the most common oil particle measurement methods. Originality/value - No other similar studies are known

  • 288.
    Berg, Sven
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Mechanics of Solid Materials.
    Lundberg, Jan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Rheological properties of contaminated oil2000In: Proceedings of the International Tribology Conference: ITC Nagasaki 2000 ; October 29 - November 2, 2000, Tokyo: Japan Society of Tribologists , 2000, 1239-1243 p.Conference paper (Refereed)
  • 289.
    Berg, Therese
    et al.
    Jönköping University, School of Engineering, JTH, Lighting design.
    Siljeskog, Adam
    Jönköping University, School of Engineering, JTH, Lighting design.
    Belysningsnivåer vid receptionsdiskar2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The purpose of this study is to identify if there is reason to change the requirementsand recommendations for illumination in reception desks areas. This studyexamines how lighting in reception desks areas actually is and how the staff perceivesthe lighting.

    Hotels today usually have subdued environments that vary according to the typeof experience intended for their guests. Our interest has been to explore the receptiondesks area as an important and separate element within the hotel. We havecompared “Ljus och Rum” recommendations (Swedish Standards Institute [SIS],2011) with actual measured light levels for four reception desks areas and examinedhow the staff perceives how the lighting affects their performance of dailytasks.

    The methods we have used are light measurement, evenness calculations, visualanalysis and surveys. Lighting measurements were performed at four differenthotels in Gothenburg. The questionnaire was directed to the hotel staff in order toascertain their perception of the lighting in and around the reception’s desks area.In order to get an impression of and gain an overall understanding for the lighting,a visual analysis was done at each hotel.

    The majority of the staff considers the lighting sufficient to perform their duties.It is clear that the lighting is perceived differently in each of the four hotels, dependingon how each hotel is formed and how the lighting is designed.

  • 290.
    Bergdahl, Eva
    et al.
    Umeå University, Faculty of Social Sciences, Centre for Regional Science (CERUM).
    Magnus, Rönn
    Umeå University, Faculty of Social Sciences, Centre for Regional Science (CERUM).
    Planering för funktionintegrering - problem och utgångspunkter2001Report (Other academic)
  • 291.
    Bergdahl, Lina
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, Urban and Regional Studies.
    CPTED för en trygg park: En studie om betydelsen av den fysiska miljöns utformning i en park ur ett trygghetsperspektiv2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
  • 292.
    Berges, Luis
    et al.
    Department of Design Engineering and Manufacturing, University of Zaragoza.
    Galar, Diego
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Stenström, Christer
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Qualitative and quantitative aspects of maintenance performance measurement: a data fusion approach2013In: International Journal of Strategic Engineering Asset Management (IJSEAM), ISSN 1759-9733, E-ISSN 1759-9741, Vol. 1, no 3, 238-252 p.Article in journal (Refereed)
    Abstract [en]

    The measurement of maintenance performance is often faced with a lack in knowledge about the real function of the maintenance department within organisations, and consequently appropriate targets from the global mission and vision are absence. Measurement metrics are not adapted to real needs, which have a strong human factor; nor is there a roadmap of the amount of data to be collected, their processing or how they are used in decision making. This article proposes a model where qualitative and quantitative methods are combined to complement the advantages of both.

  • 293.
    Berggren, David
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management, Land management, GIS.
    Förnyelselagen, möjlighet eller hot?: Förnyelse av äldre inskrivna avtalsrättigheter, Gävle kommuns hantering av förnyelsekravet2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    According to the so-called ”förnyelselagen”, the Renewal Act, all title registration of contractual rights registered before 1 July 1968 will be de-registered from the Real Property Register, unless renewal is applied for the right no later than 31 December 2018. The aim of the degree project is to pay attention to the renewal requirement. The objective is partly to investigate how the municipality of Gävle will handle the renewal requirement, and partly to facilitate the municipality to determine for which registered rights renewal needs to be sought.

    Unnecessary registered rights cause additional work and costs at cadastral procedures and the Renewal Act is considered to be an effective tool to de-register unnecessary registered rights. At the same time, concerns have been expressed that right holders will apply for renewal for all registered rights that are affected, without investigate which of them are unnecessary. In addition, there is also a concern that the renewal requirement may be overlooked by right holders for rights that are still relevant, which can lead to legal loss.

    Three methods were used in the study. Juridical method was used to investigate the legal situation regarding what happens with registered rights that are de-registered from the Real Property Register. To study how a major right holder acts, an investigation of registered rights was made in the Real Property Register regarding the municipality of Gävle. Furthermore, interviews were conducted with representatives of the municipality concerning the work with the renewal requirement.

    A result of the juridical method is that there are four different situations when an unregistered right may end. The result of the inventory in the Real Property Register, shows that there are about 1 400 registered rights that affect the properties of the municipality. The interviews resulted in that the municipality is informed about the renewal requirement and the municipality in most cases will investigate which registered rights should be renewed.

    The first conclusion is that unregistered contractual rights currently remain valid in the same manner as registered rights, but they may end in four situations if they are not monitored by the right holder. Such protection of unregistered rights is found to be practically impossible in most cases regarding the municipality of Gävle. The other conclusion is that the municipality will investigate which registered rights that need to be renewed, therefore the risk of legal loss can be assessed as low. Finally, it can be concluded that the Renewal Act is an opportunity rather than a threat for the municipality of Gävle.

  • 294.
    Berggren, Filip
    et al.
    Mälardalen University, School of Sustainable Development of Society and Technology.
    Österlund, Robin
    Mälardalen University, School of Sustainable Development of Society and Technology.
    Hur ansvariga vid vägarbeten ser på sin uppgift kopplat till säkerhet och framkomlighet2011Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In 1997, the Swedish parliament adopted a decision on Vision Zero (nollvision) in the road 

    and transport system. Vision Zero means that no one should be killed or seriously injured in 

    traffic accidents in the road transport system (Prop. 2003/04: 160). For the Transport 

    Administration in Sweden (Trafikverket), this means increased demands on security and 

    signage at road work sites around the country. This in turn means increased demands on the 

    contractors that carry out road work for the Transport Administration. The Transport 

    Administration wants a better understanding how entrepreneurs in various operational areas in 

    the Eastern Region perceive their role as responsible for safety and accessibility on roadwork 

    sites and to better understand the problems that can occur when signage is inadequate. In this 

    report, governing documents for the operating entrepreneurs have been studied, in addition, 

    searches of literature in various transport databases have been made. Interviews have been 

    made with the operating entrepreneurs who have had the opportunity to highlight their views 

    on roadwork. The results of the study are a compilation of things the contractors put emphasis 

    on. Among other things, several of them want to separate service equipment 

    (trafikanordningar) from the procurement because it is possible to win offers with a lower bid 

    amount, depending on how signage is made and safety is ensured. Many contractors also call 

    for more clarification from the Transport Administration, and say that it is often unclear what 

    the relevant directives are. Hopefully, this report will help increase the Transport 

    Administration’s understanding of the roadwork performed by contractors and help them 

    towards Vision Zero.  

     

    Keywords 

    vägarbete, trafikanordning, utmärkning, nollvision, trafikanordningsplan, konkurrenssättning, 

    skyltning, framkomlighet 

  • 295.
    Bergkvist, Joel
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, Geodesy and Satellite Positioning.
    Optimal Design of Network for Control of Total Station Instruments2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This thesis uses the Minimum Norm Quadratic Unbiased Estimation (MINQUE) to estimatestandard deviation of observations of a total station. Different setups are created byaltering the number of stations and targets and their relative position in the network tostudy the effect that different setups have to the estimation and define what are importantto minimize the effect of the setup to the estimation.A lot of research has been done around methods for estimation of variance and covariancecomponents, since it is useful in many fields. Various approaches exists to solve theproblem of variance components estimation. Geodesy is a special case, were their often isa apriori knowledge of how well an instrument is able to record measurements. There isan ISO-standard for testing and verification of geodetic instrument but also an alternativeapproach the KTH-Total Station Check.For the estimation three main types of setups were defined and used in the simulation.These main types were then altered to see how different changes to the setup effect theoverall estimation. The alterations were changes in distance between station and targets,changes in vertical distance between stations and targets and the amount of observationscarried out by adding more stations and targets to the setups.The result of the simulations shows that the tested changes in the setups do effectthe estimation. It was not possible to determine by how much for each change, becausea change in vertical displacement also meant a change in angles and distance betweenthe station and the target. Increasing the amount of stations and targets or one of themshows that standard deviation of the estimation becomes smaller. The effect can be seenindependent of which type of setup that is used. The most important factor to how goodthe estimation will be is the amount of observations.

  • 296.
    Berglund, Anders
    et al.
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Innovation and Design.
    Tretten, Phillip
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Who wins from academic consulting2013In: Design Education-Growing Our Future: Proceedings of the 15th International Conference on Engineering and Product Design Education (E&pde13, Glasgow: The Design Society Institution of Engineering Designers , 2013, 82-87 p.Conference paper (Refereed)
    Abstract [en]

    University teachers who start teaching right after graduation have not used and developed their knowledge professionally thus they have never had the opportunity to test their acquired knowledge in practice. This results in teaching that tends to be heavily theoretical because the teacher teaches what he/she has learned in studies, instead of teaching the knowledge gained through professional experience. Unfortunately a teacher can feel insecure when not knowing if their teaching reflects currently used methods and/or appropriate tools. An effect of this can be that teachers who feel insufficient in their role as teachers. The aim of this paper is to see if academic consulting not only increases the practical experience of the teacher, but also helps the teacher in their role and gives them a better understanding of what the state of the art is. While some schools have some cooperation with the business community, both in student projects and research projects, although it is not common with external non-research consultation projects, which are conducted by the university teachers. A questionnaire was sent to both teachers and students’ asking them of their experience of academic consulting’s benefits to the classroom experience. As a follow-up were several interviewed, along with clients to gain more insight. The results showed that teachers, students and the clients benefited from these types of projects.

  • 297.
    Berglund, Anders
    et al.
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Innovation and Design.
    Tretten, Phillip
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Håkansson, Anders
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Innovation and Design.
    A systematic self-assessment tool2012In: Proceedings of the 14th International Conference on Engineering and Product Design Education: Design Education for Future Wellbeing, EPDE 2012, 2012, 311-316 p.Conference paper (Refereed)
    Abstract [en]

    The Bologna Process has led to fundamental changes in the way students are taught. This in turn has led to new quality assurance systems for teaching. For good outcomes to occur both the teachers and students need to be aware of the intended learning outcome (ILO) and this is made clearer by well defined Teacher/Learner Activities (TLAs). The Systematic Grading Procedure (SGP) has been shown to assist teachers grading student’s 3D-image work, fulfilling a need for assistance in subjects requiring grading of subjective nature. With the application of this method have both teachers and students been given a tool that helps them better understand the grading process and the level of importance of different parts of the 3D work. The aim of this study was to assess students’ learning outcomes. The SGP was used and compared by both teachers and students in assessing their own work. This study used four students who were introduced to the SGP at the introduction of the course. This was done to give then an idea how they are to understand the ILOs. After one of their assignments was graded the students were given an opportunity to improve their work using the SPG. Three of the four choose to improve their work. The ensuing interview and results showed that the SGP could be used as a tool to help students and teachers with the ILO and TLAs. In addition to that the SGP should further be tested for verification.

  • 298.
    Berglund, Anders
    et al.
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Innovation and Design.
    Tretten, Phillip
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Högström, Per
    Luleå University of Technology, Department of Arts, Communication and Education, Education, Language, and Teaching.
    Is video feedback in higher education worth a byte?2015In: Great Expectations: Design Teaching, Research & Enterprise: Design Teaching, Research & Enterprise - Proceedings of the 17th International Conference on Engineering and Product Design Education (E&PDE15) / [ed] Ahmed Kovacevic ; Guy Bingham; Brian Parkinsson, Glasgow: The Design Society Institution of Engineering Designers , 2015, 258-263 p.Conference paper (Refereed)
    Abstract [en]

    Feedback can be given in various situations, like after examinations, project work, and course completion. It is widely accepted that feedback is important for students’ learning, and it can be used in various ways, such as, written, face-to-face, and with the assistance of video recordings. This study focuses on the use of video recorded feedback to gather knowledge on how video recorded feedback can enhance the students learning. Since feedback in the study was given in video recordings, an alternate way was introduced, which add further insights for teaching and learning at university levels. The results showed that 94% preferred video recorded feedback over written feedback and they, in general, preferred face to face feedback (59%). Although, follow-up questions showed that the students found the recorded option beneficial since they could review the video several times in order to see and hear exactly what was stated and what part of their work it related to. In conclusion, video feedback of student work was perceived to be beneficial and the students and the teacher positively accepted it.

  • 299.
    Berglund, Emil
    et al.
    University West, Department of Engineering Science.
    Thörnqvist, Simon
    University West, Department of Engineering Science.
    Detaljplan med enskilt huvudmannaskap för allmänna platser: planering kontra genomförande2012Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    I denna studie har vi utrett om genomförandet av allmänna platser inom detaljplanelagda områden med enskilt huvudmannaskap utförts i enlighet med kommunens intentioner. Studien baserades på elva detaljplaner inom tre kommuner i Västra Götalandsregionen där planhandlingar granskats och jämförts med de förrättningar som skett på områdena. Slutligen besiktigades också områdena för att se hur det blev i verkligheten. Granskningen visade att kommunernas intentioner har följts överlag men avvikelser förekommer. Vi kom fram till att enskilt huvudmannaskap kan vara en fungerande lösning för att säkerställa kommunens intentioner om de använder sig av planbestämmelser för att reglera utformningen av allmänna platser i detaljplan.

    En kortare studie av aktuell lagstiftning visar att kommunerna får använda sig av planbestämmelser på allmän plats vid enskilt huvudmannaskap i samma grad som kommunen skall använda sig av dessa vid kommunalt huvudmannaskap.

    Med ett kommittédirektiv som bakgrund, där det b.la. skall utredas hur tillgängligheten till allmänna platser med enskilt huvudmannaskap skall vara, har vi under besiktningen av områdena också undersökt hur tillgängligheten faktiskt var. Besiktningen visade att tillgängligheten till de allmänna platserna varierade mellan de kommuner vi granskade.

    En enkätundersökning visar att lantmäterimyndigheterna anser att samarbetet med kommunerna är för dålig p.g.a. bristande resurser. Lantmäterimyndigheterna har som utgångspunkt att följa planbestämmelser gällande utformning av allmänna platser. Det förekommer att lantmäterimyndigheterna förbiser prövning av väsentlighet och båtnad i de fall detaljplan ligger till grund för förrättningen.

    Övriga slutsatser vi dragit från arbetet är att naturområden som skall vara allmänt tillgängliga ej bör ingå i en gemensamhetsanläggning då väsentlighetsvillkoret enligt Anläggningslagen, AL kan ifrågasättas. Vi kom också fram till att anläggningsbesluten bör utformas mer utförligt för att tydliggöra kostnader och ansvar för fastighetsägare i framtiden.

  • 300.
    Berglund, Filip
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Structural analysis and condition monitoring of grinding mills: a case study2012Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Grinding mills are large rotating cylindrical steel vessels used to grind ore and minerals into finer particles. The mills are important parts of the mineral enrichment process and the grinding is the last step of the comminution process, where the particle size is reduced by a combination of abrasion and impact.The rotation of the mill under loaded conditions can result in fatigue cracks. Fatigue cracks and associated failures have been identified as a major problem in mineral processing plants. The cracks lead to unpredicted and unplanned production stoppages for inspections and for repair and replacement of the cracked mill parts. This leads to increasing costs due to production loss, additional man-hours and spare parts.The purpose of the research presented in this licentiate thesis was to calculate the structural strains, stresses, displacements, etc. in grinding mills in operation, to prevent overloading, to calculate crack propagation speeds and critical crack lengths, and to develop new improved mills that would withstand the current loading. This research has also aimed to propose, develop and test methods for the detection and monitoring of fatigue cracks in mills during operation, in order to facilitate optimal maintenance decision-making based on current crack sizes.The performed research is a case study of the secondary pebble mills of LKAB, a mining company in northern Sweden. The mills are situated inside dressing plants KA1 and KA2 in Kiruna. To achieve the goals, a number of crack detection and monitoring methods were investigated and evaluated as to their ability to find and monitor fatigue cracks on the running mills. Measurements with wireless strain measurement equipment, infrared thermography and crack propagation sensors were performed on the mills in operation.A finite element model of a mill was developed to calculate the strains and stresses in the mill at any position in the mill and for any loading condition. A variety of spatial discretizations, boundary conditions, material properties and loading alternatives were considered to simulate the behaviour of the real mill in the best possible way. To calculate the loading on the mills in operation, a mathematical model and computer software were developed to calculate the charge configuration, as well as the loading and the magnitude and distribution of the forces acting on the mill in operation. Using the finite element model and the computer software, the global displacement field of the entire mill structure was calculated using quasi-static loading for different inputs of the charge and process parameters.To verify the finite element results, the measured strain ranges for one complete rotation of the mill were compared with the corresponding calculated ones. The numerical results were also verified with logged process data, such as bearing reaction forces. One conclusion, based on the comparisons, is that the developed finite element model and the developed software tools can be considered useful for engineering applications.The developed software tools, together with the finite element model, make it possible to calculate the global displacement field of the entire mill structure for any situation. This is achieved by inputting the desired process data and charge parameters into the software, calculating the loads and force distributions, exporting them to the finite element model, and running the simulation. From the global displacement field, strains, stresses, reaction forces, displacements, etc. can be calculated with standard routines for any position in the mill.The performed research work gives a deeper understanding of the field of structural analysis and load calculation of grinding mills in operation. The complexity of modelling the behaviour of mills in operation is high. Consequently, it is difficult to obtain accurate estimations of crack propagation speeds and critical crack sizes based on the calculated stresses.It has been found that strain measurements, with strain gauges attached to the mill mandrel, can be used to detect and monitor larger circumferential cracks near the flanges in the mill in operation, since the measured strain ranges increase with the crack size. It has further been found that infrared thermography can be used as a method to indicate cracks without stopping the mill, as the increased thermal gradient around the cracks can be detected by a special type of thermal instrument.Crack propagation sensors have proven to be ideal for high-precision online monitoring of the crack propagation of smaller cracks at the corners of the manholes in the mill. Finally, it has been found that strain measurement is a useful method not only to verify finite element results and to detect and monitor cracks, but also to prevent overloading of the mill and to estimate charge features such as the filling level, the charge shape and the position of the charge circumferentially inside the mill during operation.

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