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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.
281

Optimizing roof control using probabilistic techniques in roof failure prediction /

Fraher, Richard Louis, January 1992 (has links)
Thesis (M.S.)--Virginia Polytechnic Institute and State University, 1992. / Vita. Abstract. Includes bibliographical references (leaves 72-74). Also available via the Internet.
282

Pétrographie et géochimie des dykes du camp minier de Chibougamau, Quebec /

Maillet, James. January 1978 (has links)
Mémoire (M.Sc.A)- Université du Québec à Chicoutimi, 1978. / "Mémoire présenté en vue de l'obtention de la maîtrise ès Sciences appliquées en géologie". CaQCU Document électronique également accessible en format PDF. CaQCU
283

Étude de mise en valeur des rejets de carbonate-apatite de la mine Niobec dans le but d'une utilisation comme engrais en agriculture /

Savard, Jean Y. January 1981 (has links)
Mémoire (M.Sc.A)- Université du Québec à Chicoutimi, 1981. / "Mémoire présenté en vue de l'obtention d'un diplôme de M.Sc.A. (géologie)" CaQCU Document électronique également accessible en format PDF. CaQCU
284

La distribution de l'or à la mine Montauban /

Côté, Carol. January 1989 (has links)
Mémoire (M.Sc.T.)--Université du Québec à Chicoutimi, 1989. / Document électronique également accessible en format PDF. CaQCU
285

The dream mine : a study in Mormon folklore /

Graham, Joe Stanley. January 1970 (has links)
Thesis (M.A.)--Brigham Young University. Dept. of English, 1970. / Includes bibliographical references (leaves [92]-95).
286

Geomechanical analysis applied to geological carbon dioxide sequestration, induced seismicity in deep mines, and detection of stress-induced velocity anisotropy in sub-salt environments /

Lucier, Amie Marie. Zoback, Mark D. January 1900 (has links)
Thesis (Ph. D.)--Stanford University, 2008. / Submitted to the Department of Geophysics. Copyright by the author.
287

Mining production process innovation : critical success factors to intersystem innovation at Jwaneng Mine Botswana

Mkonto, Strength 03 1900 (has links)
Thesis (MPhil (Information Science))--University of Stellenbosch, 2009. / The strategic focus in many organisations is on innovation. This is driven by the need to grow and sustain shareholder value. Innovation takes the form of business process innovation, technological innovation and social innovation through acts of organisational restructuring. Innovation strategies have become a priority for the mineral resource sector. This is due to the constraints imposed on business growth by the finite nature of the mineral resources. The need for innovation brings two organisational aspects into focus. These are the organisational system constituted of structure, process, culture and people and the business system constituted of strategy, throughput activities, resource configurations, and product or service offerings. The two systems are in constant interaction. Innovation is therefore an emergent phenomenon dependent upon interaction of such systems. A Systems approach is required to analyse the complex interactions that take place between the two systems in organisations. The Jwaneng Mine Production Interface (JMPI) consists of several inter-dependent subsystems and it is therefore appropriate to analyse it as an intersystem. The research focuses on the factors that impact the business system and the organisation system. Innovation requires the development of competencies and capability in people constituting the organisation. The way people interact with technology can be a determining factor for innovation. Theories of technology and social systems provide an important insight on how social and technological systems can be organised for innovation. The developmental paths of an organisation are influenced by its culture and structure. Theoretical insights are used to gain deeper understanding of how innovation can be derived from organisational systems and business systems. To gauge the status of innovation activities in the JMPI, specially selected case studies are used for detailed analysis. In addition, appropriate benchmarks in similar and dissimilar industries are also utilised. The critical success factors to mining production innovation are found to be social, structural and technological in nature. Innovation is shown to cover the whole life cycle of the business product or service offering. The design for innovation therefore requires a holistic approach that incorporates strategy, organisational structures, technology, business processes, leadership and people.
288

Estudo do desempenho de barreiras de geotêxtil para contenção de sedimentos carreados pelo escoamento superficial

Lima Júnior, José Carlos [UNESP] 17 February 2014 (has links) (PDF)
Made available in DSpace on 2015-03-03T11:52:41Z (GMT). No. of bitstreams: 0 Previous issue date: 2014-02-17Bitstream added on 2015-03-03T12:06:08Z : No. of bitstreams: 1 000806097.pdf: 2740283 bytes, checksum: 611b8d022113d413f8d62833ae5fef76 (MD5) / O setor de mineração brasileiro experimentou um crescimento de produção de minérios sem precedentes nos últimos anos, impulsionado pelo cenário externo favorável em relação do setor da construção civil. Consequentemente, essas atividades além de gerarem grandes volumes de rejeitos tem cada vez mais ocupado extensas áreas ficando o solo superficial totalmente desprotegido. Isso tem provocado uma maior cobrança por parte da sociedade na questão da responsabilidade ambiental e social. Como resultado, as empresas de mineração têm sido fortemente cobradas no tocante às barreiras de rejeito e principalmente quanto ao escoamento superficial de modo a proteger os recursos hídricos. Atualmente realizam-se estudos para a diminuição da contaminação de recursos hídricos em desaguamentos de rejeitos. Neste contexto, o material que vem dando resultados de qualidade e eficiência é o geotêxtil, por apresentar funções que possam ser usadas para a diminuição dos impactos. Este trabalho analisa o comportamento da barreira geotêxtil para contenção de sedimentos provindo do escoamento superficial de uma pedreira. O estudo analisou o comportamento de dois geotêxteis com diferentes gramaturas em função da respectiva abertura de filtração aparente. Para avaliar o desempenho do geotêxtil foi construído um modelo físico em laboratório de modo a avaliar o volume retido e do volume que passa, assim como, sua eficiência. Os resultados indicam que retenção do rejeito, o geoxtêxtil de menor gramatura e geotêxtil de maior gramatura apresentaram um comportamento uniforme no início devido ao agulhamento, embora o geotêxtil reutilizado de menor gramatura apresentou um maior eficiência em relação ao tempo que leva para que o rejeito não fique retido na barreira. O geotêxtil de menor gramatura apresentou uma maior eficiência quanto ao tempo de retenção embora u ma maior parcela de finos tenha passado. O geotêxtil com... / The brazilian mining industry experienced a growth of one production unprecedented in recent years, driven by favorable external scenario regarding the construction sector. Consequently, in addition to these activities generate large volumes of waste has increasingly occupied extensive areas getting totally unprotected topsoil. This has led to greater demand from society on the issue of environmental and social responsibility. As a result, mining companies have been heavily charged in respect of ensuring the barriers associated tailing and mostly about the runoff to protect water resources. Currently studies are conducted to reduce the contamination of water resources drainages tailings. In this context, the material that has been providing quality results and efficiency is the geotextile by the presenting functions that can be used for the mitigation of impacts. This paper analyzes the behavior of geotextile barrier for containment of sediment runoff stemmed from a quarry. The study analyzed the behavior of two geotextiles with different weights depending on their opening apparent filtration. To evaluate the performance of the geotextile a physical model has been built in the laboratory in order to evaluate the retentate volume and the volume that passes, as well as as its efficiency. The result indicate that for filtration and retention of the refuse, the geotextile ligher weight and greater weight had a uniform behavior at the beginning due to the needling, although geotextile reusable ligher weight had a greater efficiency compared to the time it takes to that the waste does not become trapped in the barrier. The geotextile lighter weight showed greater efficiency on the retention time although a larger proportion of fines has passed. The geotextile retains a heavier weight thinner but retained volume reaches the quota limit of basins with less time
289

Obtenção de um ataque químico padrão, zona de annealing parcial e temperatura de fechamento para o epídoto através do método dos traços de fissão

Nakasuga, Wagner Massayuki [UNESP] 28 August 2014 (has links) (PDF)
Made available in DSpace on 2015-03-03T11:52:45Z (GMT). No. of bitstreams: 0 Previous issue date: 2014-08-28Bitstream added on 2015-03-03T12:07:04Z : No. of bitstreams: 1 000806511.pdf: 1126054 bytes, checksum: 89f062b306094ea8ac4e9ba7f7b07b7b (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Durante os anos 1970 e 1980 pesquisadores da comunidade de traços de fissão discutiram os problemas relacionados à inclusão do mineral epídoto nesta metodologia, pois haviam discrepâncias significativas entre resultados apresentados pelos laboratórios/pesquisadores. Os debates não levaram a nenhuma definição clara sobre as condições de ataque químico para a revelação dos traços de fissão, bem como, da temperatura de apagamento total dos traços. Por fim, estes problemas culminaram no abandono dos estudos sobre este mineral dentro da metodologia por traços de fissão por um longo período de tempo. A fim de trazer à tona os estudos com este mineral, foram adquiridas 11 amostras de epídotos através de transações comerciais e/ou fornecidas por pesquisadores. Essas amostras formaram o grupo inicial para os estudos de ataque químico, datação e annealing deste trabalho. Após estudos sistemáticos, está sendo sugerido um ataque químico padrão de HF 40% a 15ºC por 80 minutos para epídotos com composição química Ca2Al2(A1, Fe3+)(SiO4)(Si2O7)O(OH). Ainda foram datadas 3 amostras das 11 do grupo inicial de epídoto. Essas amostras são da região do Rio Grande do Norte-Brasil, e as idades obtidas, como resultado, se mostraram compatíveis entre si. Também, foram obtidos 12 pontos de annealing (medidas de densidades superficiais e comprimentos reduzidos), 4 para o tempo de 1 hora (250, 300, 425 e 475ºC), 4 para 10 horas (250, 300, 430 e 510ºC) e mais 4 para 1000 horas (350, 500, 600 e 670ºC). Isto, tanto em densidade como em comprimento reduzidos. No caso da densidade, em cada ponto, foram analisados por volta de 100 campos e no caso do comprimento de traços confinados 100 traços medidos. Com o conjunto de dados de annealing apresentado no mestrado desde doutorando (Nakasuga 2010) mais os obtidos nesta tese pôde-se ajustar as curvas de annealing utilizando os modelos cinéticos de Guedes et. al. (2004) e... / During the 70 and 80's researchers of fission tracks is discussed about issues related to inclusion of epidote mineral in this methodology because they had significant discrepancies between results reported by the laboratories/researches. The discussions did not lead to any clear definition of the conditions of etching for the development of fission tracks, as well as the temperature of the total fading of one. Finally, these problems resulted in the abandonment of the studies on this mineral in the method of fission tracks for a long period of time. In order to bring out studies with epidote, 11 samples epidotes were acquired through purchases or provided by researchers. These samples formed the initial group for studies of etching, dating and annealing of this work. After systematic studies, a standard etching has been suggested it is 40% HF at 15ºC for 80 minutes for epidotes with chemical composition Ca2Al2(Al,Fe3+)(SiO4)(Sl2O7)O(OH). Although 3 of the 11 samples of the inicial group of epidote were dated. These samples are from Rio Grande do Norte, Brazil region and the ages obtained, as a result, proved compatible among them. Moreover, 12 points annealing (measured surface densities and reduced length) 4 for 1 hour time (250, 300, 425 and 475ºC), 4 hours for 10 (250, 300, 430 and 510ºC) and another 4 for 1000 hours (350, 500, 600 and 670ºC) were made. This, in both reduced density and length of fission tracks. In case the density at each point, were analyzed around 100 fields and in the case the length of fission tracks 100 are confined measured. In the annealing data set shown in Nakasuga (2010) and the made in this thesis were adjusted annealing curves using the kinetic m odels Guedes et. al. (2004) and Lizandrão-Filho (2014). The result led to zones of Partial Annealing of 190-370ºC for data Nakasuga (2010) and 270-440ºC for the data made in this thesis, both for the period of 1 milion years. Through the Corsini et. al... / FAPESP: 10/20496-2
290

The tectono-metallogenesis during the irumide and pan-African events in South West Africa/Namibia

Tregoning, Trevor Denzil 05 March 2013 (has links)
A large portion of South west Africa/Namibia is underlain by 2 great orogens. They are the Irumide (Sinclair/Rehoboth) and Damara Orogenies. The L-shaped Irumide Province forms part of a belt which extends over the subcontinent from Namaqualand to as far as Zambia. The volcano-sedimentary sequences of the Irumide are believed to have formed in intracratonic rifts and pull-apart basins during the period 1400 to 900 Ma. The evolution of the NW trending Sinclair Group proceeded by means of 3 major cycles each beginning with the emplacement of basic to intermediate magmas followed by felsic ones. The cycle ended off with subsidence, deposition of immature clastic debris and final tilting of the volcano-clastic sequence. It was suggested that the extensive calc-alkaline lavas present, developed within a magmatic arc above a subduction zone, but this proposal has not been generally accepted. The NE trending Klein Aub-Witvlei Basins consist essentially of red bed alluvial fans and lacustrine sediments with minor volcanics near the base. The red beds and aeolian sediments were deposited in an arid climatic condition. The regional greenschist facies metamorphism and deformation is attributed to a major tectono-thermal event at 1100 Ma. The Damara Orogen (900 - 550 Ma) forms part of the Pan-African mobile belt system of global proportions. The NE trending intracontinental branch (aulacogen) and 2 coastal branches constitute a triple junction with its focal point near Swakopmund. The NE extension of the intracontinental belt has been linked with the Lufilian Arc hosting the renown Zambian Copper Belt deposits. In South West Africa/Namibia this belt hosts many different mineral occurrences which can be grouped into rift and collision related deposits. The tectonic history of the Damara Orogen supports a geodynamic-evolution-with-time hypothesis and represents a transitional phase in which limited Wilson Cycle Tectonics was active. The Theory of Mantle Advection is invoked to explain rifting, thinning and subsidence. Extensive ensialic rifting resulted in a relatively stable Northern Carbonate Platform and several deep troughs hosting turbiditic sequences. Crustal rupture in the Khomas Trough allowed for the emplacement of ocean floor tholeiites known as the Matchless Amphibolite Belt. Subsequent ocean closure and collision resulted in deformation, metamorphism and generation of predominantly S-type granites. The southern continental plate was partially overridden by the northern plate during final collision at 550 Ma. These low angle thrust faults allowed for the emplacement of the Naukluft Nappe Complex on top of younger Nama sediments. The break up of Gondwanaland during the Mesozoic with the splitting of the Atlantic Ocean was responsible for the intrusion of anorogenic alkaline ring complexes along the extension of the NE trending transform faults within the intracontinental branch of the Damara Orogen. A close relationship between the tectonic setting and mineral deposits has been recognized in both the Irumide and Damara Orogenies. In the Irumide, stratiform syngenetic copper deposits are hosted by alluvial fan, playa and lacustrine sediments. The uninterrupted sedimentation from the Irumide to Damara Orogen resulted in similar stratiform copper deposits during the early stages of rifting. In the Damara Orogen the rifting (extensional) phase is characterized by 4 main mineralizing systems: diagenetic/syngenetic (Kupferschiefer-type), epigenetic/hydrothermal Cu-Pb-Zn (Mississippi Valley-type), volcanogenic cupriferous pyrite (Besshi-type) and volcano-exhalative Pb-Zn (Red Sea-type). The collision (compressional) phase was accompanied by 4 main mineralizing processes: epigenetic/hydrothermal Cu-Pb-Zn, hydrotheral/metasomatic Sn-W-rare earth, metamorphogenic Au and U-bearing anatectic melts. The key to the selection of viable exploration targets lies in the understanding of the field evidence and the geodynamics modelling to explain the evolution of the orogen and its associated mineral deposits.

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