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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

Applications and Development of Intelligent UAVs for the Resource Industries

Bishop, Richard Edwin 21 April 2022 (has links)
Drones have become an integral part of the digital transformation currently sweeping the mining industry; particularly in surface operations, where they allow operators to model the terrain quickly and effortlessly with GPS localization and advanced mission planning software. Recently, the usage of drones has expanded to underground mines, with advancements in drone autonomy in GPS-denied environments. Developments in lidar technology and Simultaneous Localization and Mapping (SLAM) algorithms are enabling UAVs to function safely underground where they can be used to map workings and digitally reconstruct them into 3D point clouds for a wide variety of applications. Underground mines can be expansive with inaccessible and dangerous areas preventing safe access for traditional inspections, mapping and monitoring. In addition, abandoned mines and historic mines being reopened may lack reliable maps of sufficient detail. The underground mine environment presents a multitude of unique challenges that must be addressed for reliable drone flights. This work covers the development of drones for GPS-denied underground mines, in addition to several case studies where drone-based lidar and photogrammetry were used to capture 3D point clouds of underground mines, and the associated applications of mine digitization, such as geotechnical analysis and pillar strength analysis. This research also features an applied use case of custom drones built to detect methane leaks at natural gas production and distribution sites. / Doctor of Philosophy / Drones have become an integral part of the digital transformation currently sweeping the mining industry; particularly in surface operations, where they allow operators to model the terrain quickly and effortlessly. Recently, the usage of drones has expanded to underground mines, with advancements in drone autonomy. New developments are enabling UAVs to function safely underground where they can be used to digitally reconstruct workings for a wide variety of applications. Underground mines can be expansive with inaccessible and dangerous areas preventing safe access for traditional inspections, mapping and monitoring. In addition, abandoned mines and historic mines being reopened may lack reliable maps of sufficient detail. The underground mine environment presents a multitude of unique challenges that must be addressed for reliable drone flights. This work covers the development of drones for GPS-denied underground mines, in addition to several case studies where drones were used to create 3D models of mines, and the associated applications of mine digitization. This research also features an applied use case of custom drones built to detect methane leaks at natural gas production and distribution sites.
42

The management of potable water supply in Mogwase Township, Moses Kotane Local Municipality / Daniel Kagiso Mosime

Mosime, Daniel Kagiso January 2014 (has links)
The continuous population growth and the notable development of the mining industry have resulted in challenges for potable water supply in South Africa. The ever-increasing number of people migrating to urban areas has resulted in the demand of potable water supply in South Africa. Water is regarded as a human basic right which is promulgated by the recent amendment of the potable water service provisioning Water Services Act 108 of 1997 and the National Water Act 36 of 1998. The afore-mentioned Acts started a process to address the imbalance that existed during the apartheid regime. (The apartheid regime essentially had one objective initially, namely the control of (black, coloured and Indian) people in order to protect white privilege). It was meant to separate people of different races).The Acts were formulated to address the equal distribution of national resource for all South Africans. Mogwase Township in Moses Kotane Local Municipality is undergoing continuous growth with several mining areas being developed. Consequently, the supply of potable water has been a challenge in the area. It is, therefore, in the interest of the researcher to investigate the management of potable water supply in Mogwase Township with the aim of suggesting improved service delivery by the Moses Kotane Local Municipality. Water is now recognised as a scarce resource that belongs to all South Africans. The provision of potable water by the water services authorities (WSAs) is an important basic service that faces a number of challenges, such as the use of outdated infrastructure, namely: pipelines from the Vaalkop Dam, the lack of skilled and knowledgeable people, improper planning, and the booming population that place overt pressure on the demand for effective and efficient service delivery. This research was undertaken to investigate how Moses Kotane Local Municipality which obtains its potable water supply from Vaalkop Dam can improve the supply of water in a more effective, efficient, equitable, economic and sustainable manner through improved co-operative governance and integrated water resource management (IWRM). The qualitative and quantitative research designs were used to conduct the research, which included a literature review, semi-structured interviews, data sampling and scientific analysis of the responses. The researcher arrived at logical conclusions and S.M.A.R.T. (Simple, Measureable, and Achievable Realistic Timebound) recommendations with regard to all aspects related to the future management of potable water supply in Mogwase Township. / MA (Development and Management), North-West University, Potchefstroom Campus, 2015
43

The management of potable water supply in Mogwase Township, Moses Kotane Local Municipality / Daniel Kagiso Mosime

Mosime, Daniel Kagiso January 2014 (has links)
The continuous population growth and the notable development of the mining industry have resulted in challenges for potable water supply in South Africa. The ever-increasing number of people migrating to urban areas has resulted in the demand of potable water supply in South Africa. Water is regarded as a human basic right which is promulgated by the recent amendment of the potable water service provisioning Water Services Act 108 of 1997 and the National Water Act 36 of 1998. The afore-mentioned Acts started a process to address the imbalance that existed during the apartheid regime. (The apartheid regime essentially had one objective initially, namely the control of (black, coloured and Indian) people in order to protect white privilege). It was meant to separate people of different races).The Acts were formulated to address the equal distribution of national resource for all South Africans. Mogwase Township in Moses Kotane Local Municipality is undergoing continuous growth with several mining areas being developed. Consequently, the supply of potable water has been a challenge in the area. It is, therefore, in the interest of the researcher to investigate the management of potable water supply in Mogwase Township with the aim of suggesting improved service delivery by the Moses Kotane Local Municipality. Water is now recognised as a scarce resource that belongs to all South Africans. The provision of potable water by the water services authorities (WSAs) is an important basic service that faces a number of challenges, such as the use of outdated infrastructure, namely: pipelines from the Vaalkop Dam, the lack of skilled and knowledgeable people, improper planning, and the booming population that place overt pressure on the demand for effective and efficient service delivery. This research was undertaken to investigate how Moses Kotane Local Municipality which obtains its potable water supply from Vaalkop Dam can improve the supply of water in a more effective, efficient, equitable, economic and sustainable manner through improved co-operative governance and integrated water resource management (IWRM). The qualitative and quantitative research designs were used to conduct the research, which included a literature review, semi-structured interviews, data sampling and scientific analysis of the responses. The researcher arrived at logical conclusions and S.M.A.R.T. (Simple, Measureable, and Achievable Realistic Timebound) recommendations with regard to all aspects related to the future management of potable water supply in Mogwase Township. / MA (Development and Management), North-West University, Potchefstroom Campus, 2015
44

The management of potable water supply in Khuma Township, Matlosana Local Municipality / Kagisho Simon Monnahela

Monnahela, Kagisho Simon January 2014 (has links)
The birth of a non-racial democracy in South Africa brought many challenges such as the supply of potable water to all societies irrespective of their colour or even location. Migration of people from rural to urban has increased the demand of potable water supply in many areas that were previously neglected by the former Apartheid regime. The increase of the human population in urban or developing areas of South Africa will therefore imply that various public services such as potable water supply, proper housing, electricity supply, schooling and basic health facilities should be provided in an efficient, effective and economic manner. As the resident of Khuma Township, the researcher has a keen interest in the management of potable water supply in this area, inter alia, the nature and extent of the physical environment and the efficiency and effectiveness of a potable water supply as a means of improving service delivery by the Matlosana Local Municipality to Khuma Township. The area has the history of gold mining and the majority of the people from other rural areas and neighbouring states moved into this area and were later joined by their families. This resulted in an increase in the population to a point where people were placed in dangerous areas such as underlying dolomite and along the Koekemoer spruit. For example, extension 6 is known to experience sinkholes due to underground mining activities and the underline dolomite rock. The population has increased in Khuma Township to such an extent that a shortage of potable water supply is been experienced. Khuma Township had one water reservoir for the past 40 years and Matlosana Local Municipality did not improve or developed infrastructure related to potable water supply to be able to cater for the increasing population of this area. An empirical study was conducted in among the residents of Khuma Township, Matlosana Local Municipality and role-players in the management of potable water supply. From this study, it was evident that the supply of potable water in Khuma Township is insufficient, and there was poor communication, cooperation and participation between Matlosana Local Municipality and the residents of Khuma Township. The ineffective management of potable water supply in Khuma Township by the Matlosana Local Municipality as well as ignoring the significance of settling people in a safe area that is free from water pollution, sinkholes and underlying dolomite rock left a lot to be desired. The researcher arrived at logical conclusions and recommendations with regard to all aspects related to future management of potable water supply in Khuma Township. / M Development and Management, North-West University, Potchefstroom Campus, 2014
45

The management of potable water supply in Khuma Township, Matlosana Local Municipality / Kagisho Simon Monnahela

Monnahela, Kagisho Simon January 2014 (has links)
The birth of a non-racial democracy in South Africa brought many challenges such as the supply of potable water to all societies irrespective of their colour or even location. Migration of people from rural to urban has increased the demand of potable water supply in many areas that were previously neglected by the former Apartheid regime. The increase of the human population in urban or developing areas of South Africa will therefore imply that various public services such as potable water supply, proper housing, electricity supply, schooling and basic health facilities should be provided in an efficient, effective and economic manner. As the resident of Khuma Township, the researcher has a keen interest in the management of potable water supply in this area, inter alia, the nature and extent of the physical environment and the efficiency and effectiveness of a potable water supply as a means of improving service delivery by the Matlosana Local Municipality to Khuma Township. The area has the history of gold mining and the majority of the people from other rural areas and neighbouring states moved into this area and were later joined by their families. This resulted in an increase in the population to a point where people were placed in dangerous areas such as underlying dolomite and along the Koekemoer spruit. For example, extension 6 is known to experience sinkholes due to underground mining activities and the underline dolomite rock. The population has increased in Khuma Township to such an extent that a shortage of potable water supply is been experienced. Khuma Township had one water reservoir for the past 40 years and Matlosana Local Municipality did not improve or developed infrastructure related to potable water supply to be able to cater for the increasing population of this area. An empirical study was conducted in among the residents of Khuma Township, Matlosana Local Municipality and role-players in the management of potable water supply. From this study, it was evident that the supply of potable water in Khuma Township is insufficient, and there was poor communication, cooperation and participation between Matlosana Local Municipality and the residents of Khuma Township. The ineffective management of potable water supply in Khuma Township by the Matlosana Local Municipality as well as ignoring the significance of settling people in a safe area that is free from water pollution, sinkholes and underlying dolomite rock left a lot to be desired. The researcher arrived at logical conclusions and recommendations with regard to all aspects related to future management of potable water supply in Khuma Township. / M Development and Management, North-West University, Potchefstroom Campus, 2014
46

Modelling and control of an articulated underground mining vehicle

Kohlmeyer, Rolf Reimar 12 July 2012 (has links)
The automation of the tramming or load, haul and dump (LHD) procedure, performed by a LHD vehicle, holds the potential to improve productivity, efficiency and safety in the mining environment. Productivity is mainly increased by longer working hours; efficiency is improved by repetitive, faultless and predictable work; and safety is improved by removing the human operator from the harsh environment. However, before the automation of the process can be addressed, a thorough understanding of the process and its duty in the overall mining method is required. Therefore, the current applicable mining methods and their areas of potential automation are given. Since the automation of the LHD vehicle is at the core of this project, its implementation in the tramming process is also justified. Also, the current underground navigation methods are given and their shortcomings are named. It is concluded that infrastructure-free navigation is the only viable solution in the ever-changing mining environment. With that in mind, the feasibility of various navigation sensors is discussed and conclusions are drawn. Both kinematic and dynamic modelling of LHD vehicles are introduced. Various forms of kinematic models are given and their underlying modelling assumptions are named. The most prominent assumptions concern the vehicle’s half-length and the inclusion of a wheel-slip factor. Dynamic modelling techniques, with a strong emphasis on tyre modelling, are also stated. In order to evaluate the modelling techniques, field tests are performed on the articulated vehicles, namely the Wright 365 LHD and the Bell 1706C loader. The test on the Wright 365 LHD gives a good impression of the harsh ergonomics under which the operator has to work. A more thorough test is performed on the Bell 1706C articulated loader. The test results are then compared to simulation results obtained from the kinematic models. Also, the above-named assumptions are tested, evaluated and discussed. A dynamic model is also simulated and discussed. Lastly, two localization and control methods are given and evaluated. The first method is an open-loop nonlinear optimal control strategy with periodic position resetting and the second method is a pathtracking controller. AFRIKAANS : Automatisering van die laai-, vervoer- en dompel- (LVD) prosedure het die potensiaal om die produktiwiteit, effektiwiteit en veiligheid van die mynbedryf te verbeter. Produktiwiteit word hoofsaaklik deur langer werksure verhoog, effektiwiteit word deur herhalende, foutlose en voorspelbare werk verbeter en veiligheid word verbeter omdat menslike operateurs uit die gevaarlike ondergrondse omgewing verwyder word. Voordat aandag aan die automatisering van die prosedure geskenk kan word, moet die prosedure en die algemene mynbedrywighede rakende die prosedure deeglik bestudeer en verstaan word. As gevolg hiervan word die huidige, toepaslike mynboumetodes hier gedokumenteer. Die implementering van ʼn gekoppelde LVD-voertuig in die LVD-prosesword ook geregverdig. Verder word die huidige metodes van ondergrondse navigasie genoem en hulle tekortkominge aangedui. Die gevolgtrekking dat infrastruktuur-vrye navigasie die enigste lewensvatbare navigasiemetode in die immer veranderende ondergrondsemynbouomgewing is, word ook gemaak. In die lig daarvan word ʼn verskeidenheid sensors genoem en bespreek. Kinematiese en dinamiese modellering van ʼn LVD-voertuig word bekendgestel. Verskeie kinematiese modelle en hulle onderliggende aannames word genoem. Die mees prominente aannames is die lengte van die gekoppelde voertuig se hoofdele en die insluiting van ʼn wielglipfaktor. Die tegnieke van dinamiese modellering, met die klem op bandmodellering, word ook gegee. Praktyktoetse op gekoppelde voertuie is ook gedoen om die verskillende modelle te evalueer. Die toets op die Wright 365-LVD bied goeie insig in die strawwe ergonomiese toestande waaronder die operateurs moet werk. ʼn Deeglike toets is op ʼn BELL 1706C- gekoppelde laaier, wat kinematies identies aan ʼn LVD-voertuig is, uitgevoer. Die bevindinge van die toets word met bogenoemde modelsimulasies vergelyk en gevolgtrekkings word gemaak. Laastens word lokalisiering en beheer van ʼn LVDvoertuig behandel. Twee beheermetodes, opelus- nie-lineêre optimale beheer met periodieke herstel en padvolgingbeheer word geëvalueer en bespreek. Copyright / Dissertation (MEng)--University of Pretoria, 2012. / Electrical, Electronic and Computer Engineering / unrestricted
47

Untersuchungen zur Entwicklung des Lehr- und Forschungsbergwerkes der TU Bergakademie Freiberg: Das Bergwerk 2000+

Grund, Klaus 08 January 2010 (has links)
Auf der Grundlage der Analyse der infrastrukturellen Bedingungen im Lehr- und Forschungsbergwerk der TU Bergakademie Freiberg wurden Möglichkeiten zur Weiterentwicklung des Bergwerkes untersucht. Der vorgestellte Ansatz zur Lösung der logistischen Probleme und damit verbundener Möglichkeiten zur effizienten Nutzung des Bergwerkes für Lehre und Forschung durch den Bau einer Rampe verkörpert die Basis weiterer Untersuchungen. Die Vielfalt der Probleme, die sich aus der Implementierung einer neuen Struktur in das bestehende historische Bergwerk ergeben, wurde erörtert. Gleichzeitig wurde ausführlich auf die sich ergebenden Probleme zur Gewährleistung der Personensicherheit und der Sicherheit technischer Einrichtungen, veränderter Bedingungen der Zutrittskontrolle zum Grubenbetrieb und der komplexen Struktur der Informationsverwaltung hingewiesen. Abschließend wurde die neue administrative Struktur des Bergwerkes unter wirtschaftlichen Aspekten dargestellt.
48

Aplicación de técnicas de análisis de regresión y aprendizaje automático para la estimación de sobre dilución en el método de Sub Level Stoping - Compañía Minera Condestable / Application of regression analysis and machine learning techniques for the estimation of over dilution in the Sub Level Stopping method - Compania Minera Condestable

Penadillo Palomino, Cristina Tessa 20 March 2021 (has links)
El presente trabajo de investigación tiene como objetivo aplicar técnicas de análisis de regresión y aprendizaje automático (ML) para mejorar los resultados de estimación de sobre dilución en tajos explotados por el método de Sub Level Stoping (SLS) de la Compañía Minera Condestable (CMC) a través de la generación de ecuaciones de regresión y código en lenguaje de Python para las técnicas de ML. Para la estimación de sobre dilución se analizaron las reconciliaciones de tajos explotados con el método de SLS del período 2017-2019 con la aplicación de las técnicas: Análisis de Regresión Lineal Múltiple (ARLM), regresión no lineal múltiple (ARNM) y métodos de aprendizaje automático (ML) como Máquinas de Vectores de Soporte (SVM) y bosques aleatorios (RF), lo que permitió establecer comparaciones entre los resultados a nivel predictivo y tecnológico con la metodología de O’Hara aplicada actualmente en CMC para la estimación de sobre dilución de tajos SLS. La aplicación de las técnicas mencionadas implicó variables operativas como: nivel, buzamiento, densidad, burden, espaciamiento, altura, longitud, ancho, RQD, RMR y ratio de tonelada por metro de perforación (TMP) de los tajos evaluados, mientras que el objetivo o variable dependiente fue la sobre dilución. Ello permitió inicialmente identificar que las técnicas de regresión ARLM y ARNM mejoraron el coeficiente de determinación R2 de O’Hara en 5.5% y 4.4%. Luego, con la aplicación de herramientas de aprendizaje automático se identificó que ambas técnicas (SVM y RF) lograron la mejora en 0.3% y 18.5% respectivamente. El resultado de ello fue la reducción de la diferencia de costos estimados obtenidos con la metodología de O’Hara relacionados al costo adicional por carguío y transporte de carga rota de dilución. / This research work aims to apply Regression Analysis and Machine Learning (ML) techniques to improve the results of estimating over dilution in stopes mined by Sub Level Stoping (SLS) method at Compania Minera Condestable (CMC) through the generation of regression equations and code in Python language for ML techniques. For the estimation of over dilution, the reconciliations of stopes mined with the SLS method for the period 2017-2019 were analysed with the application of the techniques: Multiple Linear Regression Analysis (MLRA), Multiple Non-linear Regression Analysis (MLNRA) and Machine Learning (ML) methods such as Support Vector Machine (SVM) and Random Forests (RF), which allowed comparisons of the results at predictive and technological level with the O'Hara methodology currently applied at CMC for the estimation of over dilution of SLS stopes. The application of the afore mentioned techniques involved operational variables such as: level, dip, density, burden, spacing, height, length, width, RQD, RMR and tonne per metre drilling (TMP) ratio of the evaluated stopes, while the objective or dependent variable was over dilution. This initially identified that the ARLM and ARNM regression techniques improved O'Hara's R2 determination coefficient by 5.5% and 4.4%. Then, with the application of machine learning tools it was identified that both techniques (SVM and RF) achieved the improvement by 0.3% and 18.5% respectively. This resulted in a reduction of the estimated cost difference obtained with the O'Hara methodology related to the additional cost of loading and transporting broken stock from the dilution. / Tesis
49

Untersuchungen zur Entwicklung des Lehr- und Forschungsbergwerkes der TU Bergakademie Freiberg

Grund, Klaus 03 March 2010 (has links) (PDF)
Auf der Grundlage der Analyse der infrastrukturellen Bedingungen im Lehr- und Forschungsbergwerk der TU Bergakademie Freiberg wurden Möglichkeiten zur Weiterentwicklung des Bergwerkes untersucht. Der vorgestellte Ansatz zur Lösung der logistischen Probleme und damit verbundener Möglichkeiten zur effizienten Nutzung des Bergwerkes für Lehre und Forschung durch den Bau einer Rampe verkörpert die Basis weiterer Untersuchungen. Die Vielfalt der Probleme, die sich aus der Implementierung einer neuen Struktur in das bestehende historische Bergwerk ergeben, wurde erörtert. Gleichzeitig wurde ausführlich auf die sich ergebenden Probleme zur Gewährleistung der Personensicherheit und der Sicherheit technischer Einrichtungen, veränderter Bedingungen der Zutrittskontrolle zum Grubenbetrieb und der komplexen Struktur der Informationsverwaltung hingewiesen. Abschließend wurde die neue administrative Struktur des Bergwerkes unter wirtschaftlichen Aspekten dargestellt.
50

Assessment of rock mass quality and its effects on charge ability using drill monitoring technique

Ghosh, Rajib January 2017 (has links)
No description available.

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