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  • 3051.
    Vagenas, Nikolaos
    Luleå tekniska universitet.
    A dispatch procedure for traffic control of a fleet of remote-controlled automatic LHDS in underground hard rock mines: modelling approach is based on simulation1990Doctoral thesis, monograph (Other academic)
    Abstract [en]

    A concept for automating Load-Haul-Dump (LHD) vehicles has stimulated considerable interest in the Swedish mining industry. In this concept, tramming and dumping operations of an LHD should be automatic. During loading, an operator from a control room fills the bucket of a vehicle via remote-control aided by a television system. The application of such a Remote-controlled/Automatic LHD (RAL) system in underground hard rock mines exhibits some operational and traffic control characteristics that have not been studied previously (e.g. vehicle motion in bidirectional lane-segments, lack of alternative routes to the same destination, stochastic nature of an RAL system due to human involvement in the loading operation). This thesis deals with the construction and implementation of a dispatch and traffic control procedure for a fleet of RAL vehicles operating in an underground mining transport layout. The development of the dispatch procedure has been based on concepts in graph theory. This dispatch procedure can perform the following tasks: Resolve traffic conflicts between vehicles during motion Plan collision-free routes Select destinations for the vehicles For studying and evaluating the operation of a fleet of RALs, a discrete-event simulation model has been developed and implemented. This, so-called PROFITIS version 2.0 model, integrates graphical modelling and presentation of RAL transport layouts with animation of the motion of vehicles during simulation. The model is used to evaluate the capacity of a future fleet of RALs which might operate in a typical transport layout at the LKAB Swedish iron ore mine in Kiruna. The research work presented in this thesis indicates that extensive studies and analysis should be performed to examine the potential and limitations of RAL systems, before any actual application is attempted in an underground mine.

  • 3052.
    Vagenas, Nikolaos
    Luleå tekniska universitet.
    Remote-controlled automatic load-haul-dump (LHD) system in underground mining1988Licentiate thesis, monograph (Other academic)
  • 3053.
    Vagenas, Nikolaos
    Luleå tekniska universitet.
    Simulation modelling and dispatch control of a fleet of remote-controlled automatic LHDS in underground hard rock mines1989Report (Other academic)
  • 3054.
    Vagenas, Nikos
    Luleå tekniska universitet.
    Dispatch control of a fleet of remote-controlled/automatic load-haul-dump vehicles in underground mines1991In: International Journal of Production Research, ISSN 0020-7543, E-ISSN 1366-588X, Vol. 29, no 11, p. 2347-2363Article in journal (Refereed)
    Abstract [en]

    Recently, a concept for automating load-haul-dump (LHD) vehicles has stimulated considerable interest in the world mining industry. In this concept, the tramming and dumping operations of an LHD should be automatic. During loading, an operator from a control room fills the bucket of a vehicle via remote-control aided by a television system. The application of such a remote-control/automatic LHD (RAL) system in underground mines exhibits some operational and traffic control characteristics that have not been studied previously in mining (e.g. vehicle motion in bidirectional lane-segments, lack of alternative routes to the same destination, stochastic nature of an RAL system due to human involvement in the loading operation). This paper presents and discusses a dispatch and traffic control procedure for a fleet of RAL vehicles operating in an underground mining transport layout. The development of this procedure has been based on concepts in graph theory

  • 3055.
    Vagenas, Nikos
    Luleå tekniska universitet.
    Prognos: a prototype expert system for fault diagnosis of the transmission system of load-haul-dump vehicles in Kiruna mine, LKAB, Sweden1992In: Expert systems in mineral and metal processing: proceedings of the IFAC workshop, Espoo, Finland, 26-28 August 1991 / [ed] Sirkka-Liisa Jamsa-Jounela; Antti J. Niemi, Oxford: Pergamon Press, 1992, p. 173-178Conference paper (Refereed)
    Abstract [en]

    As a consequence of the increasing complexity of modern mining machinery and systems, more time is consumed on repair following a breakdown. Equipment breakdowns cause lengthy and costly delays in the operation of mines. PROGNOS is a rule-based expert system for fault diagnosis of the transmission system of load-haul-dump (LHD) vehicles in Kurna mine, Sweden. This paper presents the problem approach and discusses the formulation of the knowledge base and the software implementation. The use of expert systems for fault diagnosis of mining machinery can be a cost and time effective approach of minimizing repairs in the mines

  • 3056.
    Vagenas, Nikos
    Luleå University of Technology.
    Prognos: a prototype expert system for fault diagnosis of the transmission system of load-haul-dump vehicles in Kiruna mine, LKAB, Sweden1992In: Elsevier IFAC Publications / IFAC Proceedings series, ISSN 1474-6670, Vol. 25, no 17, p. 173-178Article in journal (Refereed)
    Abstract [en]

    As a consequence of the increasing complexity of modern mining machinery and systems, more time is consumed on repair following a breakdown. Equipment breakdowns cause lengthy and costly delays in the operation of mines. PROGNOS is a rule-based expert system for fault diagnosis of the transmission system of load-haul-dump (LHD) vehicles in Kurna mine, Sweden. This paper presents the problem approach and discusses the formulation of the knowledge base and the software implementation. The use of expert systems for fault diagnosis of mining machinery can be a cost and time effective approach of minimizing repairs in the mines

  • 3057.
    Vagenas, Nikos
    Luleå tekniska universitet.
    Robotics: from industrial to mining applications: an introduction1988Report (Other academic)
  • 3058.
    Vagenas, Nikos
    Luleå tekniska universitet.
    Strategy for applying expert systems for maintenance of mining equipment in Swedish mines1991Report (Other academic)
  • 3059.
    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.

  • 3060.
    Valverius, Carl
    Blekinge Institute of Technology, Faculty of Engineering, Department of Spatial Planning.
    God Krympande Miljö: En undersökning av krympande kommuner och god bebyggd miljö2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Detta kandidatarbete undersöker hur kommuner med en krympande befolkning hanterar miljökvalitetsmålet god bebyggd miljö i deras översiktsplaner. Arbetet utfördes genom en kvalitativ textanalys på tre översiktsplaner från Arjeplog, Hofors och Jokkmokk, och försöker besvara tre frågor; Hur beskrivs befolkningsutvecklingen? vad anser kommunen är en god bebyggd miljö? Och vilka konsekvenser har dessa två delar? I till exempel Arjeplog kommun beskrivs befolkningsutvecklingen som en stor utmaning mot kommunens framtida utveckling, och att det är svårare att vända trenden på grund av de relativa höga priserna på villor. I Hofors kommun fokuserar arbetet med en god bebyggd miljö på kollektivtrafik och pendlingsmöjligheter. Jokkmokk kommun presenterar inga tydliga konsekvenser av sina ställningstaganden.  En slutsats som dras är att definitionen av god bebyggd miljö är olika i kommunerna eftersom de behöver utgå från sina egna förutsättningar och problem. En annan slutsats är att det behövs en kompetensutveckling inom social hållbarhet, med anledningen att både god bebyggd miljö och social hållbarhet inkluderar liknande koncept och idéer.

  • 3061.
    van Eldert, Jeroen
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Analysis of Excavation Damage, Rock Mass Characterisation and Rock Support Design using Drilling Monitoring2018Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Prior to an underground excavation a site investigation is carried out. This includes reviewing and analysing existing data, field data collected through outcrop mapping, drill core logging and geophysical investigations. These data sources are combined and used to characterise, quantify and classify the rock mass for the tunnel design process and excavation method selection.

    Despite the best approaches used in a site investigation, it cannot reveal the required level of detail. Such gaps in information might become significant during the actual construction stage. This can lead to; for example, over-break due to unfavourable geological conditions. Even more so, an underestimation of the rock mass properties can lead to unplanned stoppages and tunnel rehabilitation. On-the-other-hand, the excavation method itself, in this case, drill and blast, can also cause severe damage to the rock mass. This can result in over-break and reduction of the strength and quality of the remaining rock mass. Both of these attributes pose risks for the tunnel during excavation and after project delivery.

    Blast damage encompasses over-break and the Excavation Damage Zone (EDZ). In the latter irreversible changes occur within the remaining rock mass inside this zone, which are physically manifested as blast fractures. In this thesis, a number of methods to determine blast damage have been investigated in two ramp tunnels of the Stockholm bypass. Herein, a comparison between the most common methods for blast damage investigation employed nowadays is performed. This comparison can be used to select the most suitable methods for blast damage investigation in tunnelling, based on the environment and the available resources. In this thesis Ground Penetrating Radar, core logging (for fractures) and P-wave velocity measurements were applied to determine the extent of the blast damage.

    Furthermore, the study of the two tunnels in the Stockholm bypass shows a significant overestimation of the actual rock mass quality during the site investigation. In order to gain a more accurate picture of the rock mass quality, Measurement While Drilling (MWD) technology was applied. The technology was investigated for rock mass quality prediction, quantifying the extent of blast damage, as well as to investigate the potential to forecast the required rock support. MWD data was collected from both grout and blast holes. These data sets were used to determine rock quality indices e.g. Fracture Indication and Hardness Indicator calculated by the MWD parameters. The Fracture Index was then compared with the installed rock support at the measurement location.

    Lastly, the extent of the damage is investigated by evaluating if the MWD parameters could forecast the extent of the EDZ. The study clearly shows the capability of MWD data to predict the rock mass characteristics, e.g. fractures and other zones of weakness. This study demonstrated that there is a correlation between the Fracture Index (MWD) and the Q-value, a parameter widely used to determine the required rock support. The study also shows a correlation between the extent of the blast damage zone, MWD data, design and excavation parameters (for example tunnel cross section and charge concentration).

  • 3062.
    van Eldert, Jeroen
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Measuring of Over-Break and the Excavation Damage Zone in Conventional Tunneling2017In: <