Thesis (M.S.)--University of Wisconsin--Madison, 1983. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 100-107).

No description available.

Thesis (MBA (Business Management))--University of Stellenbosch, 2006. / ENGLISH ABSTRACT: Globalisation and increased communication flow in the world has increased competition tremendously over the last decade. For organisations to stay ahead of their competition it became essential to adapt quickly. Flexible low cost organisations will become leaders in the industry. Collaboration and teamwork in organisations, especially across functions, could maximise flexibility and productivity. Matrix structures were introduced in the sixties by multinational companies and by the early Seventies many other companies followed suit with mixed success. Academic interest faded after the mid Eighties. The challenge of continual, fast growing organisations is opening a debate for project management and cross-functional structures as teamwork and effective collaboration between functional departments become key to success. This study will focus on application of matrix management structures in the new millennium and project management principles applied by a literature search. The best practice model is compiled with specific application to Skorpion Zinc. Skorpion Zinc is a newly commissioned zinc mine and refinery, applying new technology to produce Special High Grade zinc. Application of this model is verified by personnel from the organisation by means of a questionnaire. Research indicates that most project orientated organisations prefer and use matrix management structures to manage their business. Successes and challenges related to crossfunctional structures are similar to those experienced in the Eighties. Implementation and management of the structure is the key to success. Selecting the correct type of matrix structure that will best support the business is vital. The study reveals that the Weak Matrix Management structure applied in the Refinery Department will enhance personnel management, project management and enable optimal utilisation of resources. In addition to the implementation of the structure focus is required in improvement of project management principles. Enabling factors to the Weak Matrix Structure that needs to be encouraged is a cooperative culture, teamwork, open and effective communication. Skorpion Zinc can use their strength of trust within departments and expand this to an interdepartmental trust. It is concluded that the study has identified the latest trends and success factors related to matrix management structures. Best practice suitable to Skorpion Zinc has been identified and verified. By applying this knowledge, the organisation can look forward to producing zinc cost effectively with a contented workforce, thus becoming a world leader in its class. / AFRIKAANSE OPSOMMING: Internasionalisering en toenemende kommunikasie vloei regoor die wereld het kompetisie geweldig laat toeneem oor die laaste dekade. Vir organisasies om kompeterend te bly het dit al belangriker geword om vinnig te kan aanpas by veranderende omstandighede. Aanpasbare, lae koste besighede sal leiers in die industrie word. Spanwerk en samewerking in organisasies, veral tussen funksionele departemente sal lei tot aanpasbaarheid van die maatskappy en produktiwiteit van werknemers. Matriks strukture was in die sestiger jare bekend gestel deur internasionale maatskappye wie se voorbeeld gevolg was deur ander maatskappye in die vroeer sewentiger jare met gemengde sukses. Akademiese belangstelling het gekwyn na die later tagtiger jare. Uitdagings van vinnig groeiende, dinamiese organisasies het opnuut debat rondom projek bestuur en matriks strukture laat opvlam as gevolg van sukses wat bereik word deur samewerking tussen funksionele departemente. Fokus van die literatuur navorsing studie sal val op die jongste toepassing van matriks organisasie strukture en projek bestuur beginsels. 'n Model van beste praktyke van toepassing op Skorpion Zinc is saamgestel. Skorpion Zinc is 'n jong sink myn en raffinadery, onlangs in gebruik gestel, wat nuutste tegnologie aanwend om Spesiale Hoe Graad sink te ontgin en produseer. Werknemers het die toepaslikheid van die model bevestig deur middel van 'n vraelys. Navorsing dui aan dat meeste projek ge-orienteerde organisasies vierkies en wend matriks strukture aan om hul besighede te bestuur. Vandag se suksesse en uitdagings verwant aan matriks strukture is baie eenders as wat ondervind was in die tagtiger jare. Implementering en bestuur van die strukture is die sleutel tot sukses. Die keuse van die matriks struktuur wat die onderneming sal ondersteun is van kardinale belang. Navorsing dui daarop dat die Afgewaterde Matriks struktuur, soos toegepas in die Produksie Afdeling, personeel bestuur, projek bestuur en optimale benutting van menslike hulpbronne sal bevorder. Dit is belangrik dat aandag toegespits word op verbetering van projek bestuur beginsels tesame met implementering van die struktuur. 'n Samewerkende kultuur, spanwerk, effektiewe en op die man af kommunikasie is ondersteunende faktore vir matriks strukture wat bevorder moet word. Die gevolgtrekking kan gemaak word dat die navorsing beste gebruike en sukses faktore van matriks bestuur uitlig. Gebruike van toepassing op Skorpion Zinc is geidentifiseer en bevestig. Deur die kennis toe te pas kan die maatskappy uitsien daarna om 'n wereld leier op sy gebied te word met lae koste sink produksie en 'n bevredigde arbeidsmag.

Thesis--University of Missouri, School of Mines and Metallurgy, 1884. / The entire thesis text is included in file. Holograph [Handwritten in entirety by author]. Title from title screen of thesis/dissertation PDF file (viewed September 24, 2008)

Thesis (Professional Degree)--University of Missouri, School of Mines and Metallurgy, 1924. / The entire thesis text is included in file. Typescript. Illustrated by author. Title from title screen of thesis/dissertation PDF file (viewed June 22, 2009)

Thesis (Ph. D.)--University of Missouri--Rolla, 2007. / Vita. The entire thesis text is included in file. Title from title screen of thesis/dissertation PDF file (viewed July 31, 2008) Includes bibliographical references (p. 185-197).

Thesis (Professional Degree)--University of Missouri, School of Mines and Metallurgy, 1939. / The entire thesis text is included in file. Typescript. Title from title screen of thesis/dissertation PDF file (viewed April 22, 2010)

Orientador: Lena Virginia Soares Monteiro / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Geociências / Made available in DSpace on 2018-08-17T17:16:01Z (GMT). No. of bitstreams: 1 Lemos_MarianaGazire_M.pdf: 12140400 bytes, checksum: 3040e2de78dfcbc8abda7081afd936fa (MD5) Previous issue date: 2011 / Resumo: A Faixa Vazante-Paracatu, localizada na porção noroeste de Minas Gerais, representa o mais importante distrito zincífero do país. Nos últimos anos, os depósitos de zinco não-sulfetados, como o de Vazante localizado nessa faixa, vem se destacando no cenário internacional devido aos teores de zinco mais elevados em relação aos de minérios sulfetados e aos avanços nas tecnologias de processamento mineral. Estudos de caracterização mineralógica e geoquímica do corpo de minério da Mina Extremo Norte (Antiga Mineração Aeirense S/A), que representa uma continuidade do trend de mineralização de Vazante, visam à identificação da forma de ocorrência e distribuição de elementos úteis que poderão vir a ser aproveitados, tais como Zn e seus possíveis subprodutos. As etapas realizadas nesse estudo incluíram trabalhos de campo, análises químicas de rocha total, petrografia, análises com uso de microscopia eletrônica de varredura e ensaios tecnológicos nos tipos de minérios identificados. Os dados levantados mostram diferenças entre o minério do Extremo Norte e da Mina de Vazante. Os corpos de minério no Extremo Norte são hospedados por unidades dolomíticas do Membro Morro do Pinheiro Inferior (Formação Serra do Poço Verde), próximo ao contato com rochas metapelíticas da Formação Serra do Garrote, ambas do Grupo Vazante. O controle da mineralização é estrutural, assim como na Mina de Vazante, mas a zona de falha que controla a distribuição dos corpos de minério apresenta traço curvo e direção N-S. A mineralização supérgena é representada pela calamina (hemimorfita), enquanto a hipógena, apresenta predominância de willemita. Altos conteúdos de ferro nas zonas mineralizadas, também uma particularidade da área, foram usados na classificação de subtipos de minérios de calamina e willemita. Apartir das relações mineralógicas, químicas e texturais, pode-se sugerir que a participação de fluidos metalíferos e meteóricos seria provável para a formação da mineralização hipógena do Extremo Norte. Neste contexto, as condições físico-químicas resultantes da mistura de fluidos para a formação do minério willemítico seriam aquelas de pH neutro a básico, resultante da maior participação de fluidos meteóricos já aquecidos ou do tamponamento devido às reações com as rochas carbonáticas, sem decréscimo acentuado de temperatura. As análises químicas mostraram que os teores de ferro do minério da antiga Mina da Masa podem ser relacionados à profundidade e ao fechamento de lentes de willemita mais profundas. Além disso, o minério da antiga Mina da Masa é mais empobrecido em elementos traços como Ag, Cd, Ge e Pb em relação ao minério de Vazante. Tal fato pode estar relacionado ao conteúdo mais baixo de sulfetos no minério do Extremo Norte. De acordo com a caracterização tecnológica, observa-se que os subtipos de minério com willemita com menores (Fé < 20%) e maiores teores de Fe (Fe > 20%), mostram tendências semelhantes em relação a sua distribuição granulométrica. O conteúdo de Zn é significativo entre as faixas granulométricas -0,15+0,11 e -0,044+0,038mm. Os teores de Fé encontram-se maiores na fração grossa, principalmente para as amostras ricas em Fe, onde os grãos de hematita estão associados à willemita ou liberados. Ao relacionar tal fato com a petrografia, pode-se concluir que isso deve-se à substituição da fase willemítica pela hematítica. Os teores de CaO e MgO apresentaram-se maiores nas frações mais finas para os dois subtipos de minério, principalmente para o subtipo rico em Fe e contribuem para fenômeno slime coating, que é resultante tanto dos maiores conteúdos de dolomita, como quantidades elevadas de hematita, que representa um corpo moedor devido à diferença em sua dureza em relação aos minerais carbonáticos. Em geral, o aproveitamento dos sulfetos do minério da Mina Extremo Norte é dificultado por sua forma de ocorrência, em inclusões muito finas na willemita, que não são liberadas mesmo em frações granulométricas finas (-0,038 mm). Espera-se que esta dissertação possa fornecer subsídios para futuros estudos geometalúrgicos, auxiliando na previsibilidade do comportamento do minério na Usina e na otimização do rendimento da planta metalúrgica / Abstract: The Vazante-Paracatu Belt, located in the northwest portion of the Minas Gerais state, is the most important Brazilian Zn district. In recent years, non-sulphide zinc deposits, such as the Vazante mine, has been highlighted in the international zinc scenario due to its higher zinc grade than those of sulphide ores and mineral processing advances. Mineralogy and geochemistry studies of the Extremo Norte orebody (former Mineração Aeirense S/A), which represents a continuing trend of mineralization in relation to that of Vazante, aim to identify the form of occurrence and distribution of useful elements, such as Zn and its byproducts. The steps carried out were field work, whole rock chemical analysis, petrography including optical microscopy and scanning electron microscopy and technological tests. The data collected showed differences between the Extremo Norte and Vazante ores. In the Extremo Norte deposit, the orebodies are hosted by dolomitic units of the Lower Morro do Pinheiro Member (Serra do Poço Verde Formation, Vazante Group), close to the contact with metapelitic rocks of the Serra do Garrote Formation (Vazante Group). The mineralization is structurally-controlled, as well as in the Vazante mine, but the fault zone in this area is a curved stroke with N-S trend. The supergene mineralization is represented by calamine (hemimorphite), while the hypogene ore comprises predominantly willemite. High contents of iron in the mineralized zones, also a main feature of the area, have been used to classify the ore subtypes. From the relationships among mineralogy, chemistry and textures, it could be suggested that the involvement of meteoric and metalliferous fluids would also be likely in the Extremo Norte area. The physicochemical conditions, resulting from the ideal mixing process for the willemite formation ore would be those of the basic neutral pH, resulting from participation of heated meteoric fluids or plugging due to reactions with carbonate rocks, without rapid decrease in temperature. The chemical analysis showed that levels of iron in the Extremo Norte ore may be related to depth and closing of deeper willemite lenses. In addition, the ore from Extremo Norte area is more depleted in minor elements, such as Ag, Cd, Pb and Ge than Vazante samples. This may be related to lower sulfide contents in the ore samples of the Extremo Nore than those typical of the Vazante ore. According to the technological characterization, it is observed that the subtypes of willemite ore show similar trends in relation to their size distribution. The content of Zn is significant in particle sizes between -0.15+ 0.11 and -0.044 0.038 mm. Fe contents were higher in the coarse fraction, especially for Fe-enriched samples, where the grains of hematite are associated with willemite or represent released particles. By linking this fact with the petrography, it is possible to conclude that this is due to the presence of hematite mass, which commonly replaces willemite. The contents of CaO and MgO was higher in finer fractions for the two subtypes of ore, especially for subtype rich in Fe and contribute to slime coating.This phenomenon is indeed related to higher contents of CaO and MgO and quantities of hematite, because it is a body grinder can be due to difference in their hardness. In general, the potential for sulphide recovery is not high due to its occurrence mode. In the Extremo Norte Mine, isolated sulphide bodies have not been recognized and sulphide phases occur only as very thinny inclusions in willemite. These inclusions were not released even in very fine granulometry. This study may provide insights for future geometallurgical studies, assisting in the predictability of the ore behavior in the plant and optimizing the efficiency in metallurgical plant / Mestrado / Geologia e Recursos Naturais / Mestre em Geociências

The thesis is inspired by recent interests in oxide zinc ores caused by new developments in the technology of hydrometallurgy. The improved techniques turned the non-sulphide zinc ores in to attractive exploration targets due to a number of advantages such as low metal recovery costs and favorable environmental aspects such as the obvious absence of sulfur (Large, 2001). Historically extraction of zinc metal from oxide ores was not possible until recently. The metallurgical complexity resulted in a lack of interest and hence some economic oxide zinc ores might have been missed by conventional exploration techniques. The study presents a review of exploration status at Skorpion mine based on different exploration techniques and their application to sulphide and oxide zinc ore exploration. The challenge facing the mineral exploration industry today is the inability to detect mineral deposits under cover. Therefore a key to successful exploration program lies in the selection of the right exploration technique. Important parameters that should be highlighted in the exploration methodology are the geological situation of an area, equipment applicability and effectiveness, survey limitation, equipment mobilization and the safety aspects involved. The aim of this thesis is to provide a general guideline for sulphide and non-sulphide zinc ore exploration on the Skorpion area and other similar geological environments. Geochemical surveys appears to be more complimentary in exploration of non-sulphide zinc exploration. Although geochemical techniques are preferred, it is equally important to choose the right soil horizon. Furthermore, sample media may mean the difference between success and failure in geochemical exploration of non-sulphide zinc mineralization, due to high mobility of zinc in the surficial environment. On cost comparison, surface geochemical surveys programs are more cost effective except for litho-geochemical sampling which are commonly carried out through subsurface drilling. Geophysical techniques have limited application in exploration of non-sulphide zinc mineralization due to a lack of major physical properties (e.g., magnetic and electrical properties) in non-sulphides unlike their sulphide counterparts. However geophysical methods are commendable in delineating massive and disseminated sulphides mainly if they are associated with major Fe minerals (pyrrhotite or magnetite). In addition, geophysical techniques may be effective in mapping of subsurface primary and secondary structures such as basin faults which might have acted as pathways for metal-rich fluids. Terms non-sulphide and oxide zinc mineralization are used interchangeably throughout the thesis. Recommendations on regional and local target generation are presented in the thesis to give some basic guide lines on target generation strategies. The most important conclusion reached in this study is that, success in exploration for non-sulphide or sulphide zinc mineralization might be enhanced through the integrated exploration methodology.

Thesis (M. Sc.)--Carleton University, 1992. / Also available in electronic format on the Internet.