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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.
211

Development of a capital investment framework for a gold mine / M. Clasen

Clasen, Mari January 2011 (has links)
This study was done against the backdrop that executives should carefully consider all the options to manage difficult periods before letting employees go, especially if they are going to rehire employees shortly after the economic recovery. Therefore, the study investigated whether investing in operational development of a plant can be used to increase feasibility, rather than to make across–the–board labour cuts. Two South African mining companies were chosen for this study. They are two investment centres at AngloGold Ashanti, Mine X Ltd. and Mine Z Ltd. The investigating project was done at Mine X to extract gold from the neighbouring Mine Z. Mine X will have access to the minerals 40 years in advance of Mine Z due to insufficient essential infrastructure at Mine Z. The life–time of the project is 18 years (estimated). The main objective of this study is to investigate the feasibility, from Mine X’s point of view, with a deepening project including Mine Z. The most significant aspect will be to determine which investment timeframe decision will gain Mine X a feasible position in terms of economic growth. This will be achieved by the following secondary objectives in making a capital investment decision: 1. To describe the nature and significance of investment decision making. 2. To recognise appropriate capital investment evaluation techniques in conjunction with sensitivity analysis. 3. To apply the techniques and sensitivity analysis in order to make a decision of a possible, feasible investment opportunity at Mine X. 4. To develop a framework to identify the project’s components and associate and access difficulties for Mine X‘s project lifecycle. The feasibility study undertakes multiple scenarios and provides recommendations and a final report, based on the scenario that is the most viable. The following techniques which were identified were used to analyse the feasibility of the project: Net present value, internal rate of return and payback period. All these above techniques will be analysed in three different scenarios, namely: 1. Mine X will stay with its current operations without any new projects. 2. The development project will begin immediately. 3. A six–month delay in development of the project. The study found that the net present value was positive, the internal rate of return was more than the discount rate and the payback period was shorter than the project’s life–time regarding to all three above–mentioned scenarios. The highest net present value is calculated in case the project starts immediately. Both the internal rate of return and the payback period indicated that a six month delay in the project is the most viable. After considering all the facts, the study concluded due to the highest net present value the best feasible recommendation would be to start the project immediately. The value of this study is that it is the first study to investigate the relationship between the viability to delay or to start the investment project immediately in the South African mining industry. This study is also unique, since it takes into account how mining industries world–wide can achieve long–term success through development projects without losing key players, due to impulsive short–term downsizing decisions. / Thesis (M.Com. (Management Accountancy))--North-West University, Potchefstroom Campus, 2012.
212

Dynamic fixture planning in virtual environments

Kang, Xiu Mei 23 September 2010 (has links)
Computer-aided fixture planning (CAFP) is an essential part of Computer-aided design and manufacturing (CAD/CAM) integration. Proper fixture planning can dramatically reduce the manufacturing cost, the lead-time, and labor skill requirements in product manufacturing. However, fixture planning is a highly experience-based activity. Due to the extreme diversity and complexity of manufacturing workpieces and processes, there are not many fixture planning tools available for industry applications. Moreover, existing CAFP methods rarely consider integrating fixture environmental factors into fixture planning. Automatic fixture planning using VR can provide a viable way for industries. This thesis develops automated approaches to fixture planning in a virtual environment (VE). It intends to address two important issues: automatic algorithms for fixture planning, and the VE to support high fidelity evaluation of fixture planning. The system consists of three parts including fixture assembly planning, feasibility analysis of assembly tools, and motion planning for fixture loading and unloading. The virtual fixture planning system provides the fixture designer a tool for fixture planning and evaluation. Geometrical algorithms are developed to facilitate the automatic reasoning. A Web-based VE for fixture planning is implemented. The three-dimensional (3D) model visualization enables the fixture simulation and validation effectively to investigate existing problems. Approaches to construct desktop-based large VEs are also investigated. Cell segmentation methods and dynamic loading strategies are investigated to improve the rendering performance. Case studies of virtual building navigation and product assembly simulations are conducted. The developed algorithms can successfully generate the assembly plan, validate the assembly tools, and generate moving paths for fixture design and applications. The VE is intuitive and sufficient to support fixture planning, as well as other virtual design and manufacturing tasks.
213

The feasibility of implementing a point-of-use micronutrient fortification among African pre-school children : a pilot study / Ogunlade, Adebayo Olakunle

Ogunlade, Adebayo Olakunle January 2009 (has links)
Background The high prevalence of micronutrient deficiencies among South African preschool children reinforces the need for an intensified micronutrient malnutrition control strategy targeting children at home or in school. The use of recently developed micronutrient powders also known as "in-home fortification" or "point-of-use fortification" can be an effective long-term, sustainable approach in improving early childhood nutrition and cognitive developmental potential. However, before embarking on large-scale, long-term, point-of-use fortification trials, it is imperative to conduct external pilot trials in which the feasibility of implementing full-scale studies can be effectively assessed. Objective The objective of this study was to assess the feasibility of implementing a point-of-use micronutrient fortification trial among African preschool children, which would aid in pilot-testing the study design, logistics and implementation process as well as reveal limitations which can be addressed before the implementation of full-scale trials. Methods Preschool children (n = 151), aged 36 -79 months with haemoglobin concentration (Hb)<= 12.5 g/dL, from eight schools in a low socio-economic community were randomly assigned to an intervention (n = 76) and a control (n = 75) groups, both receiving breakfast maize-meal porridge, either with added micronutrient or placebo powder for 52 school days. Several process evaluation indicators (fidelity, dose delivered, dose received, reach, recruitment and context) were used to assess trial feasibility. Selected indicators of early childhood development (Hb concentration, anthropometric indices and cognitive function) were used to evaluate the outcome of the intervention within the context of a pilot study. Results The process evaluation results indicate that the various implementation components were delivered with high fidelity. Capacity development and strengthening of the front-line staff cognitive assessors and study assistants) was executed as planned. The point-of-use fortificant was well accepted among the children and the mean percentage of days the point-of-use fortificant or placebo was consumed (~85%) did not differ between the groups. There were significant increases in Hb concentration (p < 0.05) from baseline to follow-up in both the intervention [mean change: 0.38 g/dL (95% CI: 0.14, 0.61 g/dL)] and control [mean change: 0.57 g/dL (95% CI: 0.35, 0.80 g/dL)] groups, however, mean change did not differ significantly between the groups (p = 0.250). The intervention did not improve any of the anthropometric indices measured in the intervention group compared to control. However, there was a medium likelihood for practical significance for the two global cognitive scores assessed, nonverbal index [intervention effects: 7.20 (95% C!: 2.60,11.81); P = 0.002, effect size: 0.55] and mental processing index [intervention effects: 2.73 (95% CI: 0.25,5.70); P = 0.072, effect size: 0.36] on the Kaufman Assessment Battery for Children, second edition. Conclusion The feasibility of implementing a point-of-use micronutrient fortification trial was demonstrated among African preschool children with potential benefits of improving their cognitive function. The most important lessons learned from this trial that could help improve similar future large-scale trials included the recruitment and training of the most eligible front-line staff as well as identifying that the use of a simple field-friendly finger prick method to measure Hb concentration may not be sufficiently sensitive to show differences in iron status after the intervention. / Thesis (M.Sc. (Nutrition))--North-West University, Potchefstroom Campus, 2010.
214

Development of a capital investment framework for a gold mine / M. Clasen

Clasen, Mari January 2011 (has links)
This study was done against the backdrop that executives should carefully consider all the options to manage difficult periods before letting employees go, especially if they are going to rehire employees shortly after the economic recovery. Therefore, the study investigated whether investing in operational development of a plant can be used to increase feasibility, rather than to make across–the–board labour cuts. Two South African mining companies were chosen for this study. They are two investment centres at AngloGold Ashanti, Mine X Ltd. and Mine Z Ltd. The investigating project was done at Mine X to extract gold from the neighbouring Mine Z. Mine X will have access to the minerals 40 years in advance of Mine Z due to insufficient essential infrastructure at Mine Z. The life–time of the project is 18 years (estimated). The main objective of this study is to investigate the feasibility, from Mine X’s point of view, with a deepening project including Mine Z. The most significant aspect will be to determine which investment timeframe decision will gain Mine X a feasible position in terms of economic growth. This will be achieved by the following secondary objectives in making a capital investment decision: 1. To describe the nature and significance of investment decision making. 2. To recognise appropriate capital investment evaluation techniques in conjunction with sensitivity analysis. 3. To apply the techniques and sensitivity analysis in order to make a decision of a possible, feasible investment opportunity at Mine X. 4. To develop a framework to identify the project’s components and associate and access difficulties for Mine X‘s project lifecycle. The feasibility study undertakes multiple scenarios and provides recommendations and a final report, based on the scenario that is the most viable. The following techniques which were identified were used to analyse the feasibility of the project: Net present value, internal rate of return and payback period. All these above techniques will be analysed in three different scenarios, namely: 1. Mine X will stay with its current operations without any new projects. 2. The development project will begin immediately. 3. A six–month delay in development of the project. The study found that the net present value was positive, the internal rate of return was more than the discount rate and the payback period was shorter than the project’s life–time regarding to all three above–mentioned scenarios. The highest net present value is calculated in case the project starts immediately. Both the internal rate of return and the payback period indicated that a six month delay in the project is the most viable. After considering all the facts, the study concluded due to the highest net present value the best feasible recommendation would be to start the project immediately. The value of this study is that it is the first study to investigate the relationship between the viability to delay or to start the investment project immediately in the South African mining industry. This study is also unique, since it takes into account how mining industries world–wide can achieve long–term success through development projects without losing key players, due to impulsive short–term downsizing decisions. / Thesis (M.Com. (Management Accountancy))--North-West University, Potchefstroom Campus, 2012.
215

Disassembly And Re-use Of Building Materials: A Case Study On Salvaged Timber Components

Isik, Aydin 01 December 2003 (has links) (PDF)
The objective of this study was to investigate the feasibility of using salvaged timber from deconstructed buildings in Turkey. The intention was to show that the re-use of &lsquo / waste&rsquo / materials, while decreasing the cost of construction also preserves the environment from wasteful and extensive use of natural resources. It is hoped that the findings of such a study will encourage professionals to use second hand timber components in Turkey. In order to deal with the waste problem and to save our planet the re-use of construction materials from economic, environmental, social, and historic points of views should be pursued. This research incorporated information about the re-use of timber, including ongoing projects around the world, as reported by the International Council for Research and Innovation in Building Construction (CIB) Task Group on Deconstruction (TG39), a local survey of individuals, organizations, and businesses that are related to the recycling and reuse of building materials. Local deconstruction works, recovery and re-use of timber elements and components were investigated on the basis of information obtained from the demolition contractors in Bentderesi locality in Ankara, a salvaged materials market. iii Moreover the study aimed to observe how used timber components are recovered from a demolition project. By observing the demolition of a building the author was able to determine the problems in recovering timber with the least damage. The findings of the investigation indicated that the architects and the building industry can play an important role to increase recovery rates and conditions of used timber components in construction, considerably. Instead of using nails for timber joints bolted connections should be preferred since they allow demounting and re-use with minimum damage during the deconstruction process. At the same time defects in timber due to extensive and unnecessary nailing can also be avoided. The decision on type of deconstruction, time and cost estimation, worker ability and sensitivity during disassembly influence the success of deconstruction. Tools and machinery used both on the work site and in the UBMs selling area have direct effects on the condition of recovered materials.
216

A Technostructure Proposal For Online Delivery Of Stps Graduate Program

Deli, Fatma 01 January 2003 (has links) (PDF)
The purpose of this thesis is finding out whether offering an Online STPS Graduate Program with a tuition fee is feasible or not. Firstly, definition and brief history of distance education is given. Secondly, distance education applications in the world and in Turkey are studied. The main part of the thesis is the cost analysis made about the online delivery of STPS Graduate Program. The cost items of offering an online course are determined and then specific cost values are assigned to these items. By determining the cost items and related cost values, course development cost is calculated. In the course development cost calculation, fixed and variable costs are seperated. Fixed cost are the set-up costs that do not depend on any variable. Variable costs on the other hand are the costs that change with the number of students attending to the online course. A specific price value ( 100$ ) is assigned as the tuition fee for one credit hour of an online course. At the end of the cost analysis, the number of students required to meet the total cost of an online course is calculated. In addition, a questionnaire made on STPS students by STPS department is used in the thesis. The results of the questionnaire and the cost analysis are combined in order to analyze the feasibility of offering an online STPS Graduate Program.
217

The Process And Feasibility Of Building Deconstruction: A Case Study In Ankara

Cakici, Fatma Zehra 01 June 2005 (has links) (PDF)
Today because of changes in the zoning plans, structural problems, building obsolescence and owner&rsquo / s wishes, old buildings are being demolished to erect newer, larger and taller ones. The objective of this study was to investigate the process and feasibility of building deconstruction. A literature survey was conducted on two unpublished theses at Middle East Technical University (METU), and publications available on web sites and international conference proceedings. Case studies were conducted on building deconstruction and demolition processes, and recovery of used building materials (UBMs) in Ankara. Information related to these issues was obtained through informal interviews with demolition contractors, demolition teams, merchants of UBMs and building contractors. Information regarding the official procedure of demolition was gathered from &Ccedil / ankaya and Yenimahalle Municipalities. This study confirmed that recovery and reuse of UBMs is a continual practice in Ankara. In the light of case studies and interviews, it was possible to determine the problems in building deconstruction, such as building systems, materials, components and connections that give rise to difficulties during the deconstruction of buildings. It was also observed that UBMs are being reused either as it is or after modifications, and waste timber components are sold for fuel, while only metals are recycled to be used in new production. On the other hand, reinforced concrete components such as slabs, columns and beams can neither be reused nor recycled, and thus they are wasted. The findings of the investigation indicated that building deconstruction practices were found to be feasible and profitable job. The success of building deconstruction is dependent on type of tools used, sufficient time, and worker ability and experience, whereas the feasibility of deconstruction depends on the quality, quantity, type and condition of materials, components and connections used in a building.
218

The use of the World Wide Web in epidemiological research /

Ekman, Alexandra, January 2006 (has links)
Diss. (sammanfattning) Stockholm : Karolinska institutet, 2006. / Härtill 4 uppsatser.
219

A recourse-based solution approach to the design of fuel cell aeropropulsion systems

Choi, Taeyun Paul. January 2008 (has links)
Thesis (Ph. D.)--Aerospace Engineering, Georgia Institute of Technology, 2008. / Committee Chair: Mavris, Dimitri; Committee Member: German, Brian; Committee Member: Haynes, Comas; Committee Member: Masson, Philippe; Committee Member: Soban, Danielle.
220

A feasibility study of a domestic airport-ferry link : a Delphi evaluation /

Tsui, Chun-fai, Joseph. January 1994 (has links)
Thesis (M.A.)--University of Hong Kong, 1994.

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