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Functional workwear for miners working in the worlds largest underground mine : In what way can the future workwear for an extreme mine environment improve safety, facilitate the work flow as well as increase the comfort for workers situated more than 1045 meter below ground?Müller, Malin January 2014 (has links)
PROBLEM This is my graduating thesis from the bachelor program in Industrial Design from Umeå Institute of design. In this project I have looked at in what way the future work wear for an extreme mine environment could improve safety, facilitate the workflow as well as increase the comfort for workers situated more than 1045 meters below ground. I have collaborated with LKAB in Kiruna, Sweden. LKAB is a mining company, exporting iron ore from the worlds largest underground iron ore mine. In the Kiruna mine, a new main level was recently opened at the level of 1365 meters. The extreme conditions down at this depth have created new challenges when it comes to work wear for the employees. METHODS AND FINDING RESULT During the project I have used several methods, all following a typical Industrial Design methodology. I started with visiting the mine, having a look at the entire process and talking to workes. After this I wrote a brief for the project, containing information on what the problem is today. I made an other trip to the mine to host a Pin-Point meeting and a workshop together with workers from different positions and work places within the mine. This to gain a further and more specific understanding in the problem -s. The workshop I hosted was to see what they themselves thought would be good solutions. Other methods I've used is survey, sketch ideation, evaluations with users, interviews, observations, visits to manufacturers, visit to the industrial wash / warehouse and mock-ups. I divided the problems in to categories: The fit of the clothes Ability to carry tools Material Functions / Adjustments The project has resulted in a concept of a new trouser and a new jacket for the workers at the LKAB iron or mine in Kiruna. The garments are of a lighter more durable material than the garments used today. The jacket and the trouser have now more specific pockets and are placed in better positions than earlier. I also tried to place seams better, this to avoid any discomfort and work related injuries. One of the problems today was that the jacket for some, created a pressure over the neck. I've added adjustment possibilities to the garments and inserted "softed" materials in some places to increase level of comfort. The result is portrayed as a full size model, in a women’s fit. RESULT The project has resulted in a concept of a new trouser and a new jacket for the workers at the LKAB iron or mine in Kiruna. The garments are of a lighter more durable material than the garments used today. The jacket and the trouser have now more specific pockets and are placed in better positions than earlier. I also tried to place seams better, this to avoid any discomfort and work related injuries. One of the problems today was that the jacket for some, created a pressure over the neck. I've added adjustment possibilities to the garments and inserted "softed" materials in some places to increase level of comfort. The result is portrayed as a full size model, in a women’s fit.
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Application of Background Oriented Schlieren (BOS) in Underground Mine VentilationJong, Edmund Chime 12 May 2011 (has links)
The schlieren technique describes an optical analysis method designed to enhance light distortions caused by air movement. The ability to visualize gas flows has significant implications for analyzing underground mine ventilation systems. Currently, the widely utilized traditional schlieren methods are impractical underground due to complex equipment and design requirements. Background oriented schlieren (BOS) provides a solution to this problem. BOS requires two primary components, a professional quality digital camera and a schlieren background. A schlieren background is composed of a varying contrast repetitive pattern, such as black and white stripes or dots. This background allows the camera's sensor to capture the minor light diffractions that are caused by transparent inhomogeneous gases through image correlation. This paper investigates a possible means of mitigating some of the major problems associated with surveying underground mine ventilation systems with the BOS method.
BOS is an imaging technique first introduced in 1999 that allows the visualization of flowing inhomogeneous transparent media. In ventilation surveys, BOS can be used to attain qualitative data about airflows in complex areas and methane emissions from coal. The acquisition of such data would not only enhance the understanding of mine ventilation but also improve the accuracy of ventilation surveys. As an example, surveys can benefit from small scale BOS investigations around fans, regulators, overcasts, and critical junctions to identify effective data gathering positions. Regular inspections of controls and methane monitoring points could also be improved by the systematic nature of BOS.
Computer programs could process images of each location identically regardless of quantity. BOS can then serve as a check to identify items that were overlooked during the routine inspection. Despite the potential of BOS for ventilation analysis, several limitations still exist. These issues are sensitivity threshold and quantification of flow data. This paper specifically examines the qualitative potential of the BOS technique for imaging various underground ventilation flows and outlines initial experimental efforts used for the evaluation.
Three primary experiments were conducted to evaluate BOS as a potential qualitative analysis technique for underground mine ventilation. The first experiment used BOS to image of flow induced by an axial vane fan and an axial flow fan using an artificial background and an imitation rock background. This experiment showed that the BOS system was unable to image isothermal airflow from either fan. Heated airflow could be visualized with both fans using the artificial striped background but not with the imitation rock background. The BOS system lacked the sensitivity necessary to image isothermal airflow from the two fans. The focus of the overall BOS study was changed to explore higher pressure airflows through a regulator.
The second experiment used BOS to image flow through a regulator induced by an axial flow fan using an artificial striped background. The BOS images were compared to ones produced by a traditional schlieren single mirror systems for validation of the BOS experimental design. This experiment was unable to image isothermal airflow through the regulator from either system. However, heated airflow could be visualized by both systems. The BOS and traditional schlieren systems used in this experiment lacked the sensitivity necessary to image isothermal airflow through a regulator. However, the BOS procedures were successfully validated by the ability of both the BOS and traditional schlieren systems to image heated airflows. The focus of the study was changed to explore methane gas emissions.
Numerous mining industry techniques already exist to quantify methane content. However, methane content is different from the actual methane emission rate of exposed coal. Emission rates have been modeled using numerical simulation techniques, but the complexity of the methane migration mechanism still requires physical data to achieve higher accuracy. The third experiment investigated the feasibility of using the BOS technique for imaging methane flow by imaging methane emission from a porous medium. Laboratory grade methane was directly injected into a Brea sandstone core sample using a flexible tube.
The BOS system was successfully able to image methane desorption in this study. A repeating pattern consisting of alternating black and white stripes served as the schlieren background for the Nikon D700 camera. The ability to image methane emission even at low injection pressures (i.e. 20 psi) demonstrates that actual methane desorption from coal can potentially be imaged. This result can only be conjectured because of a lack of research in the area of methane emission. Despite this issue, the experimental results suggest that BOS can be feasibly utilized to image methane emissions from coal in an underground mine.
The results of the three experiment demonstrated that the potential for large scale implementation of BOS in underground mines does exist. Qualitative BOS information has the potential in the practical sense to optimize the procedures of ventilation surveys and design of ventilation monitoring equipment. For example, images of methane flow in active mining areas can be used to optimize the positioning of auxiliary ventilation equipment to dilute known areas of high methane concentration. BOS images could also be used to re-evaluate the placement of methane monitors on mining equipment to better facilitate the detection of dangerous methane concentrations in active mining areas. For these reasons, further investigation into the BOS technique for use in imaging underground airflows with differential temperatures and methane emissions in underground coal mines is suggested as an addendum to this study. / Master of Science
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Strategic Design of an Underground Mine under Conditions of Metal Price UncertaintyMcIsaac, George 28 April 2008 (has links)
Long-term mine plans are based on forecast future metal prices. By the time the development is put in place, the forecasts may have been proved wrong and the production plan might not meet the company's financial objectives. At that point, the common reaction to this situation is to create a new revised long-term plan and spend more capital, only to find out at a later time that the metal prices have changed again. This results in an inefficient use of capital with low returns to the investors.
The objective of this thesis is to develop a methodology to determine the cut-off grade and production rate of a narrow-vein underground mine such that the long-term strategic plan is robust. As a requirement to do so, it is necessary to have a good understanding of the resources, revenues, capital and operating costs as a function of the design parameters. Also, the operational limits of the mine must be determined so that the solution is practical. Afterwards, annual metal prices are randomly generated with a Monte Carlo process on stochastic metal price models, and the combination of production rate and cut-off grade yielding the highest net present value is identified and recorded. This process is repeated many times, and the probabilities of the solutions occurring at any given design combination are calculated. The results are plotted on a bubble graph, where the size of a bubble is directly proportional to the probability a solution occurs at that point. Finally, the combination with the largest bubble is the solution, as this point has the highest probability of yielding the highest net present value in most circumstances.
The model was first tested on an actual gold-copper orebody where very detailed resource and cost information was available. The methodology was applied with success and the solution reflected the important impact of the copper milling and roasting process on revenues. Other tests were then done on a hypothetical gold orebody and the results showed a great degree of sensitivity to the average grade of the deposit. / Thesis (Ph.D, Mining Engineering) -- Queen's University, 2008-04-25 12:42:24.623
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Mobile application design for contextual usability and operability in underground mines / Design av en mobilapplikation för kontextuell användbarhet och genomförbarhet i en undergjordsgruvaTesanovic, Manuela, Al-mufti, Summia January 2020 (has links)
The aim of the thesis was to develop a usable mobile application prototype to be used in the underground mining environment. In order to fulfill the aim, the research question How can a mobile application be designed for usability with focus on operability for an underground mine? was researched, analysed and answered. The main methods for driving the design process were ISO 9241-210, Human-centred design for interactive systems, requirement engineering and conceptual design. The results of the thesis were based on qualitative data, collected from semi-structured interviews from five respondents. These respondents had a background as a operator in underground mines in different countries. The qualitative data was analysed and interpreted into functional and non-functional user requirements. The user requirements in parallel with design principles were used to produce a final concept that would be transformed from a low fidelity into a high fidelity prototype. The high fidelity prototype was developed using Android Studio, Java and later tested and evaluated using SUS questionnaire and usability heuristics to rate the overall usability of the application . The answer to the research question lied in the methodology used in this thesis. This was achieved by involving the stakeholders, people affected by the future design in the entire process, with different methodology during the different phases of the design process.
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Computer aided underground mine design and drafting packageFountaine, Elise V. January 1988 (has links)
No description available.
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A CAD approach to optimize underground mine design and planningSridhar, Chaluvadi K. January 1986 (has links)
No description available.
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Approaches to Simulation of an Underground Longwall Mine and Implications for Ventilation System AnalysisZhang, Hongbin 19 June 2015 (has links)
Carefully engineered mine ventilation is critical to the safe operation of underground longwall mines. Currently, there are several options for simulation of mine ventilation. This research was conducted to rapidly simulate an underground longwall mine, especially for the use of tracer gas in an emergency situation. In an emergency situation, limited information about the state of mine ventilation system is known, and it is difficult to make informed decisions about safety of the mine for rescue personnel. With careful planning, tracer gases can be used to remotely ascertain changes in the ventilation system. In the meantime, simulation of the tracer gas can be conducted to understand the airflow behavior for improvements during normal operation.
Better informed decisions can be made with the help of both tracer gas technique and different modeling approaches. This research was made up of two main parts. One was a field study conducted in an underground longwall mine in the western U.S. The other one was a simulation of the underground longwall mine with different approaches, such as network modeling and Computational Fluid Dynamics (CFD) models. Networking modeling is the most prevalent modeling technique in the mining industry. However, a gob area, which is a void zone filled with broken rocks after the longwall mining, cannot be simulated in an accurate way with networking modeling. CFD is a powerful tool for modeling different kinds of flows under various situations. However, it requires a significant time investment for the expert user as well as considerable computing power. To take advantage of both network modeling and CFD, the hybrid approach, which is a combination of network modeling and CFD was established. Since tracer gas was released and collected in the field study, the tracer gas concentration profile was separately simulated in network modeling, CFD model, and hybrid model in this study. The simulated results of airflow and tracer gas flow were analyzed and compared with the experimental results from the field study.
Two commercial network modeling software packages were analyzed in this study. One of the network modeling software also has the capability to couple with CFD. A two-dimensional (2D) CFD model without gob was built to first analyze the accuracy of CFD. More 2D CFD models with gob were generated to determine how much detail was necessary for the gob model. Several three-dimensional (3D) CFD models with gob were then created. A mesh independence study and a sensitivity study for the porosity and permeability values were created to determine the optimal mesh size, porosity and permeability values for the 3D CFD model, and steady-state simulation and transient simulations were conducted in the 3D CFD models. In the steady-state simulation, a comparison was made between the 3D CFD models with and without taking the diffusivity of SF6 in air into account.
Finally, the different simulation techniques were compared to measured field data, and assessed to determine if the hybrid approach was considerably simpler, while also providing results superior to a simple network model. / Master of Science
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Investigation of Inertial Navigation for Localization in Underground MinesSvensson, John January 2015 (has links)
This thesis project considers the potential use of inertial navigation on a consumer grade tablet mounted in a vehicle in an underground mine. The goal is to identify which sensors and techniques are useful and to design a navigation algorithm based on those results. The navigation algorithm is intended to work alongside the current received signal strength indication (RSSI) positioning system. Testing of the gyroscope, accelerometer and magnetometer sensors suggest that, while dead reckoning is likely not precise enough, an orientation filter can be designed that can be used for navigation. A complementary orientation filter using the gyroscope and accelerometer is then designed that shows better results than the default sensor fusion solutions available in Android. The filter is expandable and can come to include magnetometer data in the future. Based on the outputs of this filter, a navigation algorithm based onangle matching with map information is proposed. Precise positioning in an underground mine can be crucial to employee safety, and may also bring production benefits.
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Modelling and control of an autonomous underground mine vehicleDragt, Bruce James 28 August 2007 (has links)
The mining industry is constantly under pressure to improve productivity, effciency and safety. Although an increased use of automation technology has the potential of con- tributing to improvements in all three factors mines have been relatively slow to make use of automation technology. Automation in the underground mining environment is a challenging prospect for a number of reasons not least of which being the diffculties and associated costs of installing infrastructure in this hazardous environment. The work described in this dissertation focuses on the modelling of a Load-Haul-Dump or LHD vehicle for the purpose of autonomous navigation and control. Considerable progress has been made in automating underground mining vehicles in recent years, and successful test installations have been made. There are still however a number of shortcomings in the existing autonomous underground mine vehicle navigation systems. This dissertation attempts to address some of these problems through the development of a more accurate vehicle model for an LHD vehicle incorporating some vehicle and tyre dynamics thereby potentially reducing the number of sensors and the amount of installed infrastructure necessary to implement the vehicle navigation system. Simulation results are provided for different vehicle modelling techniques and the results are compared and discussed in terms of their suitability for physical implementation in an underground mine. / Dissertation (MEng (Electronic Engineering))--University of Pretoria, 2007. / Electrical, Electronic and Computer Engineering / MEng / unrestricted
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Scheduling of an underground mine by combining logic based Benders decomposition and a constructive heuristicLindh, Emil, Olsson, Kim January 2021 (has links)
Underground mining is a complex operation that requires careful planning. The short-term scheduling, which is the scheduling of the tasks involved in the excavation process, is an important part of the planning process. In this master thesis we propose a new method for short-term scheduling of a cut-and-fill mine operated by the mining company Boliden AB. We include a new aspect of the problem by incorporating a priority between the excavation locations of the mine. The priority feature allows the user to control the output of the scheduling and to direct resources to the locations where they are most needed according to the long-term plans. Our solution method consists of two components: a constructive heuristic method that construct a complete solution by solving partial scheduling problems containing subsets of tasks, and a logic-based Benders decomposition scheme for solving these partial problems. The computational performance of the proposed method is evaluated on industrially relevant largescale instances generated from data provided by Boliden. Comparisons are made with applying a constraint programming solver on the complete problem and with replacing the logic-based Benders scheme by applying a constraint programming solver on the partial scheduling problems, respectively. Results show that the heuristic method combined with the logic-based Benders decomposition scheme outperforms the other two methods on all instances.
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