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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

Mineral Beneficiation : a continuing African paradox or a panacea for economic growth and skills development

Kola, Trevor Tebogo January 2019 (has links)
Africa is rich with plentiful mineral resources, yet it is a continent associated with underdevelopment, low economic growth and unskilled labour. Arguments abound that if developing countries added more value to their commodities locally, rather than exporting them to other countries in a raw and unprocessed format, their key economic indicators, such as employment and economic growth, would be enhanced. This study explored debates by scholars and policymakers, who either support or are against the position that mineral beneficiation is a panacea to Africa’s economic challenges. The study explored arguments by scholars and policymakers as to why African countries fail to pursue mineral beneficiation which has subsequently relegated their economies to the bottom end of economic development. The research explored how International Relations (IR) scholars in the past tried to define development. These debates on development were explored using the theoretical frameworks of modernisation and dependency. The study found that these debates, have highlighted the important role which mineral resources play in international relations. Diplomacy and foreign policy were found to be key aspects in the debates on mineral beneficiation in the continent. The study employed a qualitative research approach to explore arguments by scholars and policymakers on whether the continent should beneficiate its mineral resources. Data was collected, analysed and categorised. The findings of the research were discussed based on the themes which emerged from the literature reviewed. The study focused on whether by beneficiating minerals locally, the continent could realise sustainable economic growth for its citizens. The study explored whether debates by scholars, mining industry and government policymakers could dispel or support the argument that mineral beneficiation is a panacea for sustainable economic growth and skills development in the continent. The study found that debates on whether African governments should beneficiate their abundant mineral resources will continue to evolve and develop. Key words: mineral resources; underdevelopment; economic growth; mineral beneficiation; comparative advantage; skills development; employment creation, diplomacy, resource diplomacy, upstream and downstream linkages. / Mini Dissertation (MA)--University of Pretoria, 2019. / University of Pretoria / Political Sciences / MA / Unrestricted
282

Utsläpp av Koldioxid vid transporter av bergmaterial i projektet Trängslet

Persson, Jennifer January 2020 (has links)
A renovation of the dam in Trängslet hydroelectric power plant is necessary for there to continue to be hydropower at the facility in the future. The power plant is located in Österdalälven in Älvdalen and is operated by Fortum. Trängslet is one of Sweden’s largest hydroelectric power plants with a reservoir stretching 70 km in length and has been operational since 1960.  The renovation of the dam will continue until 2024 and one part of the renovation is that bedrock must be blasted away in order to improve the water purification. The rock material should then be reused as reinforcement of the dam, instead of storing it. This contributes to a carbon dioxide reduction by not having to retrieve rock material from a nearby quarry. The purpose of the study was to identify which production method that produced the least amount of carbon dioxide from transport in the mass handling of rock materials from the blasting area, of three different presented transportation alternatives. The results show that the option Skanska uses today (option 1) provides a carbon dioxide reduction of approximately 58%, when the comparison has been made with option 2. A comparison was then made between options 1 and option 3 which showed that the reduction in carbon dioxide emissions was about 84%.  The study also shows that with the help of a carefully planned production method, carbon dioxide emissions can be reduced, and that Skanska today uses the most environmentally friendly option (option 1) for the project Trängslet. A further reduction in carbon dioxide emissions can be done by switching fuel for transport from what is used today (MK1 Diesel) to HVO Diesel 100, which would then reduce carbon dioxide emissions by up to 83%.
283

Förstudie om byggande av parkeringshus i Kvarnberget i Karlstad

Söderqvist Wermelin, Albert January 2023 (has links)
The background for this degree project being carried out is that there are not enough parking spaces in Karlstad Municipality. Then an idea came from Veidekke's side to break out the rock in Kvarnberget to build parking spaces.
284

Bone Mineral Density Determination Using Digital Radiography

Cottreau, Michelle 10 1900 (has links)
There is a need for an improved bone mineral density measurement procedure for neonates. Currently, measurements are made using single photon absorptiometry (SPA). The poor reproducibility of this method means that it has little direct clinical diagnostic application and is therefore not suitable for diagnosing disease in individual patients. A technique using digital radiography has been developed to measure bone mineral density. Digital images of phantoms and chicken bones were acquired at two kvp settings of a digital angiographic unit. Digital information from water, aluminum and lucite phantoms were used to calculate effective mass attenuation coefficients of the phantom materials. These values were subsequently used in bone mineral density calculations of sections of the chicken bones. The bone mineral densities of the chicken bones obtained from the digital radiography method were compared to SPA measurements. The digital radiography method gave consistently higher bone mineral densities for the bones than SPA. This could be due to the differences in measurement technique as SPA scans a single slice whereas digital radiography images a large area of the bone. / Thesis / Master of Science (MSc)
285

Pricing of domestically consumed oil in Iran

Hatami, Hossein 22 August 2009 (has links)
As an oil exporting country, Iran heavily depends on the revenues generated from the sale its oil to the world. Oil revenues currently constitute about ninety percent of the nation's foreign exchange earnings, and serves as the most important determinant of all economic activities in the country. The dependency on oil incomes is anticipated to continue in the future, however, with the given proved stocks of oil and the country's potentials to instal higher production capacity, the rapidly increasing demand for oil in the domestic market may soon create undesirable consequences by severely limiting the availability of oil for export purposes. This is a factor of major concern for Iran as a developing country whose development plans and projects are to be met remarkably through the exports of its oil. The present study reviewed the domestic pricing policies for oil products in Iran and investigated the effects of these policies on the rapidly increasing demand for oil which has been experienced in the past few decades. The varying effects of these policies which have for a long time persisted on an artificially low domestic prices were examined in relation to the role of the world market structure for oil. Also, the alternative policies for optimal pricing of oil products based on the opportunity cost of the oil consumed in Iran were introduced in order to control and moderate the current rate of increase in demand for oil, thereby securing a longer availability of oil for both domestic consumption and export purposes. The opportunity cost of the oil was in turn analyzed under both competitive and non-competitive scenarios for the world oil market. In the non-competitive scenario, the role of OPEC policies and strategies which might restrict the total production and/or exports of oil from Iran were discussed and their impacts on the opportunity cost of the oil used in the internal market were examined. In another attempt, the opportunity cost of oil and the opportunity cost of foreign exchange were used to determine the amounts of real subsidies paid by the government on four main petroleum products including gasoline, kerosene, gas oil, and fuel oil consumed in Iran every year. The real subsidies paid in the years surveyed in this research were derived by applying the appropriate exchange rate for dollar to the international price of each product in any given year. The results of this study revealed that the nation could increase its revenues and promote the overall welfare of the country by optimally pricing of its oil for the internal consumption. / Master of Science
286

Innovative methods for long-term mineral forecasting

Jeon, Gyoo Jeong January 1989 (has links)
This study presents improved methods for long-term forecasting of mineral demands. Intensity of use, both in its simple, original form and as described by richer economic relations is one such method, particularly when intensity of use is estimated using rigorous statistical methods. Additionally, this dissertation explores the implications of the learning curve for long term forecasting of mineral demands. This study begins by considering the empirical evidence which applies when a learning curve is present. Then, if a learning pattern is present, the learning model is used to examine an economic measure for specified levels of economic activity. This dissertation also provides some empirical results on the learning curve in mineral industries and demonstrates how the learning model can be used as an economic forecasting tool. As an alternative to the intensity of use and learning models, there is a vector model, either using time varying coefficients or expressed as a transcendental function, to capture dynamics. This model estimates the time varying parameters from the vector space instead of the variable space. The major advantage of this model is that it honors correlations between variables. This is especially important in ex ante forecasting in which explanatory variables themselves must be forecast to obtain a forecast of the dependent variable.
287

Orbital forcing of deep-ocean current-controlled sedimentation in the Northeast Atlantic during the Quaternary

Nolan, Stephen Richard January 1999 (has links)
No description available.
288

An investigation of the kinetics and an assessment of the economics of ultrafine grinding of coal for mineral liberation

Kalligeris-Skentzos, Andreas January 1987 (has links)
No description available.
289

A model for relationship building and maintaining tenure in the foreign work environment

Ward, Milton Hawkins January 1995 (has links)
No description available.
290

Electrochemical studies of rare earth and transition metals in molten NaCl-KCl

Robinson, Katie Jane January 1993 (has links)
No description available.

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