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  • 1.
    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, p. 135-149Article 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.

  • 2.
    Forsman, Bo
    et al.
    Luleå tekniska universitet.
    Rönnkvist, E.
    Vagenas, Nikos
    Luleå tekniska universitet.
    Truck dispatch computer simulation in Aitik open pit mine1993In: International Journal of Mining, Reclamation and Environment, ISSN 1748-0930, E-ISSN 1748-0949, Vol. 7, no 3, p. 117-120Article in journal (Refereed)
    Abstract [en]

    Using METAFORA's dispatch rules the truck/shovel system in the Aitik mine was simulated for evaluating alternative dispatch control strategies. The Maximize Trucks rule gave about the same total production (ore+waste) as the Fixed Dispatch rule but a 7% lower ore production. The Maximize Loaders rule gave the lowest production. METAFORA was also used for planning alternative routes for transport of waste. The paper indicates that the use of software like METAFORA can result in a substantial reduction of time, effort and cost in shovel/truck system design and evaluation

  • 3.
    Ghodrati, Behzad
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Hoseinie, Hadi
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Garmabaki, Amir
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Reliability considerations in automated mining systems2015In: International Journal of Mining, Reclamation and Environment, ISSN 1748-0930, E-ISSN 1748-0949, Vol. 29, no 5, p. 404-418Article in journal (Refereed)
    Abstract [en]

    Automation is the operation of machinery or processes by devices, such as robots and machines, able to make and execute decisions without human intervention. Automation is one of the most attractive research and development areas in mining, as it aims to solve many technical, production and safety problems in current and future mining. This paper studies the structure of automated mining systems from a reliability and failure occurrence perspective. It reviews the main subsystems and related failure modes. Based on field investigation and a literature review, it highlights some critical issues and technical difficulties. Finally, it presents some challenges for future automated mines and offers some related solutions

  • 4.
    Gupta, Suprakash
    et al.
    Department of Mining Engineering, Indian Institute of Technology (BHU), Varanasi.
    Kumar, Uday
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    An analytical hierarchy process (AHP)-guided decision model for underground mining method selection2012In: International Journal of Mining, Reclamation and Environment, ISSN 1748-0930, E-ISSN 1748-0949, Vol. 26, no 4, p. 324-336Article in journal (Refereed)
    Abstract [en]

    Decision making in mining, especially the selection of an appropriate stoping method for an ore deposit, is a critical and challenging task owing to its compliance with a set of criteria. The lack of quantitative data and the qualitative nature of the task forces one to adopt an experience- and intuition -based technique like the analytical hierarchy process (AHP). This article examines the application of the AHP for the selection of an appropriate stoping method from a group of alternatives. The developed model has been verified by a number of case studies.

  • 5.
    Gustafson, Anna
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Lipsett, Michael
    Mechanical Engineering, University of Alberta, Edmonton.
    Schunnesson, Håkan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Galar, Diego
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Kumar, Uday
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Development of a Markov model for production performance optimisation: Application for semi-automatic and manual LHD machines in underground mines2014In: International Journal of Mining, Reclamation and Environment, ISSN 1748-0930, E-ISSN 1748-0949, Vol. 28, no 5, p. 342-355Article in journal (Refereed)
    Abstract [en]

    This paper compares three ways to operate a load haul dump (LHD) machine, manual operation, automatic operation (fleet operation) and semi-automatic operation, to find the best operating mode. In a fault tree analysis, different failures are classified and analysed, but the way to recover from certain states is not accounted for, which is something a Markov model can handle. The paper is based on the analysis of real data from an underground mine. A Markov model has been built for mining application and it is shown that a semi-automatic LHD has the highest probability of being in a productive state since it has the advantage of changing operating modes (manual and automatic) depending on the need and situation. Hence, the semi-automatic LHD is the best choice from an operational point of view. The paper fills a gap in the literature on manual vs. automatically operated LHDs by providing a new way of evaluating the operating mode of LHDs using Markov modelling, while considering the operating environment.

  • 6.
    Gustafson, Anna
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Schunnesson, Håkan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering.
    Galar, Diego
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Kumar, Uday
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    The influence of the operating environment on manual and automated load-haul-dump machines: a fault tree analysis2013In: International Journal of Mining, Reclamation and Environment, ISSN 1748-0930, E-ISSN 1748-0949, Vol. 27, no 2, p. 75-87Article in journal (Refereed)
    Abstract [en]

    The automated load-haul-dump (LHD) machines have the potential to increaseproductivity and improve safety, but there are many issues to be considered when optimising the operation of LHDs. Today’s focus on improved equipment reliability is part of the problem, and another difficult issue is the special conditions and constraints of the operating environment. For automated LHDs, the latter issue is even more important, as humans have been removed from the production area and are not close by to solve the problems. The purpose of this paper is to find the causes of LHD idle time and to study their impact on the operation of LHDs. In this study, real-time process data and maintenance data from an underground mine in Sweden have been refined and integrated. The study takes into account the complexity of the mine environment, discusses the factors to be considered when optimising and automating the operation and uses fault tree analysis (FTA) to analyse the idle time.

  • 7.
    Hamodi, Hussan
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Ahmadzadeh, Farzaneh
    Division of Product Realization, Mälardalen University, Eskilstuna.
    Lundberg, Jan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Ghodrati, Behzad
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Economic lifetime prediction of a mining drilling machine using an artificial neural network2014In: International Journal of Mining, Reclamation and Environment, ISSN 1748-0930, E-ISSN 1748-0949, Vol. 28, no 5, p. 311-322Article in journal (Refereed)
    Abstract [en]

    This study develops models for predicting the economic lifetime of drilling machines used in mining. It uses three cases, each represented by a MATLAB code, to develop an optimisation model. The resulting ORT is fed as input to an artificial neural network (ANN) and the results translated into a relatively simple equation. The study finds that increasing the purchase price and decreasing the operating and maintenance costs will increase a machine's ORT linearly. Decreased maintenance cost has the largest impact on ORT, followed by increased purchase price and decreased operating cost. The ANN method gives a series of basic weight and response functions which can be made available to any engineer without the use of complicated software. It also helps decision-makers determine the best time economically to replace an old machine with a new one; thus, it can be extended to more general applications in the mining industry

  • 8.
    Hoseinie, Hadi
    et al.
    Shahrood University of Technology.
    Ataei, Mohammad
    Shahrood University of Technology.
    Khalokakaie, Reza
    Shahrood University of Technology.
    Ghodrati, Behzad
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Kumar, Uday
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Reliability analysis of cable system of drum shearer using power law process model2012In: International Journal of Mining, Reclamation and Environment, ISSN 1748-0930, E-ISSN 1748-0949, Vol. 26, no 4, p. 309-323Article in journal (Refereed)
    Abstract [en]

    In this article, the reliability of the cable system of a drum shearer machine was studied and analysed using operation and maintenance data from an Iranian mine for a period of two years. The tests for trend and serial correlation show that the times between successive failures for the cable system are not independent and identically distributed. A goodness-of-fit test shows that the power law process model provides a good fit to the failure data of this system. After parameter estimation for the power law model, reliability and failure rate plots were obtained. Based on analysis and results, a period of 125 h was defined as the reliability-based maintenance interval for the cable system of the shearer. The analysis shows that, by using this strategy, the reliability of the system will improve by at least 50%.

  • 9.
    Hoseinie, Hadi
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Ghodrati, Behzad
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Kumar, Uday
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Cost-effective maintenance scheduling of cutting arms of drum shearer machine2014In: International Journal of Mining, Reclamation and Environment, ISSN 1748-0930, E-ISSN 1748-0949, Vol. 28, no 5, p. 297-310Article in journal (Refereed)
    Abstract [en]

    Cutting arms are the main productive units of coal shearer machine that contact directly with coal seam. More importantly, the cutting arms operate under a high-stressed environment. In this paper, in order to suggest an optimum maintenance plan for the subsystem of shearer machine, firstly, we conducted a failure and reliability analysis using the data acquired from the Parvade coal mine, Iran over the two years. The analysis shows that the Power Law Process model provides a good fit to the failure data. Also, we applied estimated distribution functions and calculated cost parameters to identify the cost-based optimum preventive maintenance interval. Furthermore, we conducted a sensitivity analysis of the studied machine and identified that if we consider the variation of the world price of the raw coal then the maintenance plan is sensitive to the price. The analysis showed that, big changes in world price of raw coal are not so effective on maintenance plan but have a considerable effect on maintenance costs of the cutting arms of the shearer machine. However, the effects of this change on reliability improvement are almost zero.

  • 10.
    Huang, Yi
    et al.
    Luleå tekniska universitet.
    Kumar, Uday
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Optimising the number of load-haul-dump machines in a Swedish mine by using queuing theory: a case study1994In: International Journal of Mining, Reclamation and Environment, ISSN 1748-0930, E-ISSN 1748-0949, Vol. 8, no 4, p. 171-174Article in journal (Refereed)
    Abstract [en]

    This paper discusses the determination of optimal number of Load-Haul-Dump (LHD) machines for a given mine using queuing theory model. The number of LHDs is determined by taking into account the performance of LHD, the performance of repairshop, and economic factors such as operators salary, maintenance cost, price of an LHD machine, etc. It is shown with example that queuing model can accurately calculate the probability of a given number of LHD machines for production. This paper also illustrates with an example that the number of LHD machines estimated by using queuing model is more accurate compare to the method using binomial distribution, etc. The example used in this paper is from a Swedish mine

  • 11.
    Huang, Yi
    et al.
    Luleå tekniska universitet.
    Wänstedt, Stefan
    Luleå tekniska universitet.
    Application of Kalman learning algorithm multilayer neural network to estimates of ore grades1998In: International Journal of Mining, Reclamation and Environment, ISSN 1748-0930, E-ISSN 1748-0949, Vol. 12, no 1, p. 19-27Article in journal (Refereed)
    Abstract [en]

    Lead and zinc grades are estimated along boreholes in an ore body based on geophysical logging data by using a Kalman learning algorithm, which a variety of a backpropagation neural network. Data are acquired from seven boreholes in the Zinkgruvan Mine. Five of the boreholes are used for training the network and two boreholes are used for testing the successfulness in employing the network results. The principal idea of the Kalman learning algorithm is discussed. The minimum error rates, average prediction errors and optimum number of training epochs of lead and zinc is presented. The Kalman learning algorithm is more effective than the conventiaonal backpropagation algorithm in predicting ore grades

  • 12.
    Kumar, Rajesh
    et al.
    Luleå University of Technology.
    Kumar, Uday
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Service delivery strategy: trends in mining industries2004In: International Journal of Mining, Reclamation and Environment, ISSN 1748-0930, E-ISSN 1748-0949, Vol. 18, no 4, p. 299-307Article in journal (Refereed)
    Abstract [en]

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

  • 13.
    Kumar, Uday
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Study of problems caused by oversized boulders in a mine production system: a case study1997In: International Journal of Mining, Reclamation and Environment, ISSN 1748-0930, E-ISSN 1748-0949, Vol. 11, no 2, p. 69-73Article in journal (Refereed)
    Abstract [en]

    The aim of this paper is to present a study that deals with the problem of oversized boulders in a mine production system. This work was performed to study and analyze the disturbances caused by oversized boulders and estimate their impact on the production system at the LKAB Kiruna Iron Ore Mine, Kiruna (KIOM). The results from this study show that by elimination of oversized boulders from the production process, the production capacity and system utilization of a mine like KIOM can be considerably improved.

  • 14.
    Kumar, Uday
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Granholm, Sven
    Luleå tekniska universitet.
    Elbrond, Jörgen
    Mine system availability concepts1987In: International Journal of Mining, Reclamation and Environment, ISSN 1748-0930, E-ISSN 1748-0949, Vol. 1, no 3, p. 209-213Article in journal (Refereed)
    Abstract [en]

    During the last few years, there has been a marked tendency in mining industry to adopt complex and sophisticated technology to make mining operations economically viable. The concepts of integrated operating systems are being gradually introduced with increasing pace of automation in mines. This paper discusses the concepts and various forms of system availabilities which can be used by mine engineers and managers for controlling the system performance. Examples are given to show the differences between these availabilities. The concept of availability target setting is also introduced in brief.

  • 15.
    Kumar, Uday
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Rutqvist, J.
    Aitik.
    Jadmalm, R-E.
    Aitik.
    Truck maintenance at the Aitik copper mine1989In: International Journal of Mining, Reclamation and Environment, ISSN 1748-0930, E-ISSN 1748-0949, Vol. 3, no 4, p. 181-186Article in journal (Refereed)
    Abstract [en]

    The operation and maintenance activities are integrated to a greater extent at Aitik to enhance the total productivity of the mine. The area of maintenance is identified as a strategic cost center by the Aitik management for cost control. This paper discusses the maintenance practice, the organizational set up, the achivements and the maintenance strategy for the coming years for the Transport Division of the Aitik mine.

  • 16.
    Mundry, S.
    et al.
    Longwall Automation Department, Caterpillar Global Mining Europe, Luenen.
    Gajetzki, M.
    Longwall Automation Department, Caterpillar Global Mining Europe, Luenen.
    Hoseinie, Hadi
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Longwall automation: productivity and coal quality enhancement2015In: International Journal of Mining, Reclamation and Environment, ISSN 1748-0930, E-ISSN 1748-0949, Vol. 29, no 5, p. 357-367Article in journal (Refereed)
    Abstract [en]

    This paper provides a general review of longwall automation systems, discussing the results of implementing automation, with a focus on shearer automation. A case study in an Australian longwall mine investigates the effects of automation on productivity, production rate and cutting profiles. The results reveal that with automation, productivity increased by 10% and the production rate increased by almost 22%. In addition, automation resulted in smooth production and accurate cutting profiles three months after installation

  • 17.
    Paraszczak, Jacek Jack
    et al.
    Department of Mining, Metallurgical and Materials Engineering, Université Laval, Quebec City.
    Gustafson, Anna
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Schunnesson, Håkan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Technical and operational aspects of autonomous LHD application in metal mines2015In: International Journal of Mining, Reclamation and Environment, ISSN 1748-0930, E-ISSN 1748-0949, Vol. 29, no 5, p. 391-403Article in journal (Refereed)
    Abstract [en]

    Due to safety concerns, automation of load-haul-dump (LHD) machines receives considerable attention from the mining industry. This paper analyses and discusses the issues and problems related to implementation and use of autonomous LHDs in underground metal mines. It presents the need for safety measures, infrastructure and discusses technical problems encountered. The paper looks also into technical and operational issues (reliability, maintainability, utilisation, production rate, etc.) as compared to conventional manually operated machines. Conclusions focus mostly on the aspects requiring attention before and after the implementation of autonomous loading systems in order to maximise the chances that they deliver expected benefits

  • 18.
    Rustan, Agne
    Luleå tekniska universitet.
    Burden, spacing and borehole diameter at rock blasting1992In: International Journal of Mining, Reclamation and Environment, ISSN 1748-0930, E-ISSN 1748-0949, Vol. 6, no 3, p. 141-149Article in journal (Refereed)
    Abstract [en]

    Most text books on rock blasting claim that the relationship between burden and borehole diameter is linear. The statistical calculation presented here with real values from one hundred open pit and underground mines indicates that the relationship follows a power function. For underground mines the burdens are consistently lower than those for open pit mines because of higher ore densities, greater confinement in blasting, and finally greater demand for well fragmented rock. The results shown in this paper are recommended to be considered in basic teaching of rock blasting technique. The formulas can be used for a first rough estimation of practical burden and spacing. The formulas do not however give any information about the fragmentation. For that purpose it is necessary to use other formulas not described in this paper.

  • 19.
    Rustan, Agne
    et al.
    Luleå tekniska universitet.
    Nie, Shulin
    Luleå tekniska universitet.
    New method to test the rock breaking properties of explosives in full scale1992In: International Journal of Mining, Reclamation and Environment, ISSN 1748-0930, E-ISSN 1748-0949, Vol. 6, no 4, p. 191-200Article in journal (Refereed)
    Abstract [en]

    During our research it was found that, still today, the rock breaking properties of an explosive can not be accurately determined by laboratory test or theoretical calculations. The new test method proposed here for bench blasting is based on single hole blasts in model- and full scale with different burdens up to and greater than the critical burden. The tests in full scale should be done with that hole diameter, length of hole, explosive and stemming etc., desired to be used in the real operation. The new method includes determination of the fragment size distribution, the backbreak, the throw, the centre of gravity change and the damage to the remaining rock for each burden tested. This will yield the maximum information possible for understanding how the explosive interacts with the rock. The field tests to examine the single hole blasts were done at Storugns limestone quarry on Gotland, and the model blast tests at Lulea University of Technology. They showed that there exist a good correlation between the model- and full scale tests regarding the angle of breakage versus burden and the relation of k50 versus burden, where the function has the same shape, and finally the power for the specific charge is the same both in the model and full scale. Critical burden and fragmentation gradient are well correlated with the impedance of the rock in the model tests. It seems that the model test can reveal many of the rock breaking properties of an explosive in full scale. The test procedure used for the model and full scale test were therefore proposed as a first idea to an international standard. Based on the systematic investigation carried out at Storugns limestone quarry it was theoretically possible to increase the profit up to 8 million SEK/year by changing burden and spacing and thereby reducing the amount of fines (

  • 20.
    Saiang, David
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Basarir, Hakan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Assessment of slope stability using fuzzy sets and systems2013In: International Journal of Mining, Reclamation and Environment, ISSN 1748-0930, E-ISSN 1748-0949, Vol. 27, no 5, p. 312-328Article in journal (Refereed)
    Abstract [en]

    To assess the stability of slopes, mining and geotechnical engineers frequently use empirical rock mass classification and characterisation systems. These methods are practical and often very useful in the preliminary design stage. Slope mass rating (SMR) system is one of the commonly used empirical methods to assess the stability of slopes. The SMR is obtained correcting basic rock mass rating (RMR) using four joint adjustment factors that consider the geomechanical relationship between the slope face and the joint affecting rock mass as well as the excavation method used. The factors included in the SMR system such as basic RMR, and correction factors involve some drawbacks such as uncertainties sourced from qualitative criteria, sharp class boundaries and fixed rating scales. These drawbacks are sourced from the complex nature of rock mass. To deal with these uncertainties, the fuzzy set theory is applied in this study to reliably determine basic RMR and adjustment factors. It was seen that fuzzy set theory can sufficiently cope with the common drawbacks in the determination of factors included in the SMR system.

  • 21.
    Salama, Abubakary
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Nehring, Micah
    School of Mechanical and Mining Engineering, The University of Queensland.
    Greberg, Jenny
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Operating value optimization using simulation and mixed integer programming2014In: International Journal of Mining, Reclamation and Environment, ISSN 1748-0930, E-ISSN 1748-0949, Vol. 28, no 1, p. 25-46Article in journal (Refereed)
    Abstract [en]

    Mining operations around the world will increasingly need to operate at greater depths. This significantly influences the complexity of ore extraction and ore transportation to the surface. The increase in mine depth leads to increases in haulage distance from mine areas to the mine surface. This results in an increase in energy costs to haul material further. Due to the increasing cost of future operations, the choice of the haulage method becomes an important factor in the optimization of the mine plan. The haulage process is one of the most energy intensive activities in a mining operation, and thus, one of the main contributors to energy cost. This paper presents the comparison of the operating values of the mine plans at depth levels of 1,000, 2,000, and 3,000 meters for diesel and electric trucks, shaft and belt conveyor haulage systems for the current and a predicted future energy price scenario. The aim is to analyze the impact of energy requirements associated with each haulage method, as well as the use of alternative sequencing techniques as mine depth increases. This study is carried out using a combination of discrete event simulation and mixed integer programming as a tool to improve decision making in the process of generating and optimizing the mine plans. Results show that energy cost increases across each haulage method at both current and future energy prices, with increasing depth. This study thus provides a broad and up to date analysis of the impact on operating values that may be experienced with the use of the main haulage systems available at present. Also, the study shows how the combination of discrete event simulation and mixed integer programming generates a good tool for decision support.

  • 22.
    Santelices, Gabriel
    et al.
    Department of Mining Engineering, Pontificia Universidad Católica de Chile, Santiago.
    Pascual, Rodrigo
    Pontificia Universidad Católica de Chile, Department of Mining Engineering, Pontificia Universidad Católica de Chile, Santiago.
    Lüer-Villagra, Armin
    Department of Engineering Sciences, Universidad Andres Bello, Santiago.
    Cawley, Alejandro Mac
    Department of Industrial Engineering, Pontificia Universidad Católica de Chile, Santiago.
    Galar, Diego
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Integrating mining loading and hauling equipment selection and replacement decisions using stochastic linear programming2017In: International Journal of Mining, Reclamation and Environment, ISSN 1748-0930, E-ISSN 1748-0949, Vol. 31, no 1, p. 52-65Article in journal (Refereed)
    Abstract [en]

    Equipment selection is a key strategic decision in the design of a material handling system, because an improper one will lead to operational problems and unnecessary investment costs. It involves determining the number and combination of loaders and trucks which will move the material, fulfilling a specified production schedule. Previous works have addressed this problem with deterministic approaches, without considering the inter-dependent availability of trucks and loaders. In order to fill this gap, we developed a stochastic model that combines the selection and equipment replacement problems, subject to a stochastic production rate constraint. This is a new idea that will help decision-makers to decide faster and more reliable. The proposed model optimises the fleet by minimising the total life cycle costs. To solve it, we used a linearisation approach that reduces the computational effort. We tested our approach with a benchmark model, using a mining case study. Results indicate that the solutions ensure with a high probability a determined production target, producing good robust solutions compared to the deterministic counterpart.

  • 23.
    Vagenas, Nikos
    et al.
    Luleå tekniska universitet.
    Kumar, Uday
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Rönqvist, Erika
    Analysis of truck maintenance characteristics in a Swedish mine1994In: International Journal of Mining, Reclamation and Environment, ISSN 1748-0930, E-ISSN 1748-0949, Vol. 8, no 2, p. 65-71Article in journal (Refereed)
    Abstract [en]

    This paper discusses the analysis of the maintenance data of a fleet of Caterpillar trucks (789 model) deployed at the Aitik open pit mine, a subsidiary of Boliden Mineral AB in northern Sweden. The purpose with the analysis is to evaluate the maintenance characteristics of this truck fleet. Graphical methods in conjunction with analytical methods have been used to analyze the maintenance and repair statistics and to evaluate the overall performance of the trucks.

  • 24.
    Villegas, Tomas
    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.
    Time-dependent movements of the hangingwall at the Kiirunavaara mine2012In: International Journal of Mining, Reclamation and Environment, ISSN 1748-0930, E-ISSN 1748-0949, Vol. 26, no 2, p. 119-133Article in journal (Refereed)
    Abstract [en]

    The hangingwall deformation behaviour at the Kiirunavaara mine has been characterised after several years of collecting surveying data from the ground surface. The monitoring system was implemented to track surface subsidence because the city of Kiruna and the railway are situated on the hangingwall. Data time–displacement and time–velocity curves were used and different stages of deformation behaviour were identified – regressive, progressive and steady state. The movement starts with a regressive behaviour for which subsidence is characterised by continuous deformations. At the end of this stage the movement accelerates, marking the beginning of the progressive behaviour where subsidence becomes more discontinuous. A steady state stage is reached when the strength of the failure surface decreases to the residual value. To predict displacement in the vicinity of the railway, accumulated displacements per year were analysed for several stations for which data for the full regressive stage were available. Displacement tendencies were fitted with quadratic polynomial functions. Therefore, the rate of movement follows a linear trend with a constant acceleration. Finally, a critical horizontal strain limit was determined based on the estimated displacement.

  • 25.
    Wijaya, Andi
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Lundberg, Jan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Kumar, Uday
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Downtime analysis of a scaling machine2012In: International Journal of Mining, Reclamation and Environment, ISSN 1748-0930, E-ISSN 1748-0949, Vol. 26, no 3, p. 244-260Article in journal (Refereed)
    Abstract [en]

    Scaling machines are identified as one of the major contributors to unplanned downtime. In general, to gain a better understanding of downtime, an analysis of the downtime should be performed. Downtime analysis usually involves a group consisting of many people with various backgrounds. The use of a visualisation method can act as a bridge that eliminates the knowledge gap within the group. The present study has two purposes: firstly to develop a method for visualisation of downtime and secondly to analyse the downtime of a scaling machine utilising the proposed visualisation method. The proposed method provides a visualisation of the downtime estimation and the precision and the uncertainty of the estimation at a given confidence level, as well as the factors influencing the failure. An analysis of the failures of the critical components of the scaling machine has also been conducted and suggestions for improvement have been proposed.

  • 26.
    Wu, Changming
    Luleå tekniska universitet.
    Percussive energy transfer in pneumatic top hammer rock drills1991In: International Journal of Mining, Reclamation and Environment, ISSN 1748-0930, E-ISSN 1748-0949, Vol. 5, no 1, p. 33-38Article in journal (Refereed)
    Abstract [en]

    A mathematical model of pneumatic roll drills is introduced. This model takes into account the local deformation of impact ends of piston and shank adapter. For this model, there is a good agreement between theoretical and experimental results. Two dimensionless parameters related to the mass of piston, the local deformation of impact ends, characteristic impedance of rod, and force-penetration characteristic at bit-rock interface, are introduced. The analysis indicates that the checking of these dimensionless parameters and letting them be in certain ranges are helpful for the design of pneumatic rock drills to achieve high efficiency of energy transfer.

1 - 26 of 26
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