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Sources used by medical doctors, pharmacists and patients to acquire drug-related information.Mogaila, Andrew Mamphatlo. January 2008 (has links)
Thesis (MTech. degree in Pharmaceutical Sciences)--Tshwane University of Technology, 2008.
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Treatment of landfill leachate from a H:H and G:L:B+ site in a pilot scale aerobic nitrogen removal biological systemTraut, Melanie January 2007 (has links)
Thesis (MTech. degree in Water Care ) - Tshwane University of Technology, 2007. / This research project investigated the total nitrogen removal capabilities of a nitrification
and denitrification system treating two medium strength municipal landfill leachates. The
characteristics of the leachates differed as one was obtained from general waste (GLB+)
and the other from mixed industrial and general waste (H:h). This project was
commissioned to develop a leachate treatment philosophy and a leachate management plan
for the Vissershok landfill site near Cape Town. The aim of this leachate treatment trial
project was to establish leachate treatability of different types of leachate, characterise
leachate and effluent quality, determine alkalinity requirements, assess hydraulic retention
periods and sludge production and confirm whether leachate quality can inhibit successful
treatment in a sequencing batch reactor system.
The two units were operated as simple Sequencing Batch Reactors (SBRs) by treating the
leachate in a biological treatment process. Both units were initially seeded with activated
sludge obtained from a sewage treatment works. Provision was made to supplement
carbonaceous nutrient and phosphorus to the system. In the first stage of the study a
controlled nitrification system was maintained to treat ammoniacal-nitrogen and the next
stage denitrification was used to treat nitrate and nitrite-nitrogen levels. A completely
automated daily cycle was used to treat the leachate and altered according to process
requirements.
The results showed that during nitrification ammoniacal-nitrogen concentrations as high as
2032.4 mg/l were consistently reduced to less than 0.1 mg/l. Similarly, for denitrification,
nitrate-and nitrite-nitrogen concentrations were also consistently reduced to less than 0.1
mg/l, with a methanol utilisation ratio of CH3OH:N at 4.80:1. Chemical oxygen demand
(COD) removal efficiencies were in the range 57-65% depending on loading rates applied.
In conclusion it was shown that:
(a) the biodegradable organics (COD) was reduced considerably
(b) complete nitrification and denitrification occurred
(c) no constituents of the leachate caused inhibition of the biological process.
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Use of total organic carbon analyses on a wastewater treatment plantDu Toit, Wynand January 2002 (has links)
Thesis (MTech. degree inChemistry.)--Tshwane University of Technology, 2010. / Introduction: Since the establishment of relationships between BOD, COD and TOC in early 1980’s, total organic carbon (TOC) analysis has been the
analytical backbone of many water treatment laboratories (Furlong et al. 1999). It is only a question of time before South Africa follows suite, if only to
adhere to export legislation and requirements. The question is whether TOC is just another expensive analytical tool for policing effluent, or is TOC results valid criteria for monitoring pollution.
Aim: The purpose of this project was to evaluate the determination of TOC as a management tool on a wastewater treatment plant (WWTP) and compare it to the chemical oxygen demand (COD) analysis traditionally applied.
Experimental: Five sampling points throughout the wastewater treatment plant were evaluated. A possible comparison between TOC and COD was
investigated.
Sampling was done using an ISCO 3700 portable sampler at each individual sampling point. The samples were filtered and analysed for TOC in the
laboratory using an ISCO EZ 3500 TOC analyser. COD analysis was done colorimetrically by using a Hach DR 2000 photometer. Both analyses were
done according to standard methods for water and wastewater. Because the ISCO EZ 3500 TOC is an online instrument, it was evaluated at two of the
wastewater treatment plant.
Results: The analysis of TOC is a more rapid method than COD for the determination of organic load and thus has the potential for better early
warning and pollution control management.
The change in chemical composition of raw sewage made it difficult to find consistent correlation between COD and TOC results. However, it was found that an online TOC analyses was a practical alternative to COD for plant control, process management and monitoring of inflow and effluent flows in wastewater treatment plant.
Conclusion: Limitations of TOC analysis must be considered and include practical problems due to the high content of suspended solids in raw sewage and activated sludge, as well as the partial oxidation of certain organic compounds by ultra-violet/persulphate digestion.
Although COD analysis is chemically hazardous and time-consuming compared to TOC analysis, it is not likely that TOC will replace COD on the
WWTP, due to historical data accumulation, practicality and people’s natural opposition to change. However, it is hoped that the results of this study will
increase knowledge about TOC and be used for practical implementation where this technique has advantages over COD
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Preconcentration of trace and ultra-trace levels of platinum group metals in water.Marais, Anne Fiona. January 2012 (has links)
Thesis (MTech. degree: Chemistry) / Trace and ultra-trace levels of platinum group metals (PGMs) in waste effluent pose an increasing risk of exposure to human and aquatic organisms. These metal ions accumulate in environmental matrices such as water, soil and sediments thereby aggravating the situation. In addition, industrial and automotive catalytic emissions of PGMs are increasing worldwide and both mechanical and thermal wear have been found to increase the risk of exposure. Currently, methods for the determination of low levels (μg/L) of PGMs require expensive and sophisticated instrumentation. The objective of this study was to investigate the type of bonding that would lead to preconcentration of low levels of Pt, Pd and Rh ions onto suitable solid phase adsorbents, allowing for the monitoring of their possible presence in river water samples taken downstream of platinum refineries. Preconcentration prior to analysis will enable the metal ions of interest to be determined on a less expensive instrument, such as an Flame Atomic Absorption Spectrometer, Electro Thermal Atomic Absorption Spectrometer, or at most, by use of Inductively Coupled Plasma-Optical Emission Spectrometry. Different solid phase extraction methods were applied including maize tassel, four commercially available resins and two modified resins. Results, particularly for the adsorption of Pt, were excellent with up to twenty two times the original concentration of this metal ion being recovered.
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Virtualization performance in private cloud computing.Thovheyi, Khathutshelo Nicholas 04 October 2019 (has links)
M. Tech. (Department of Information Communication Technology,
Faculty of Applied and Computer Sciences), Vaal University of Technology. / Virtualization is the main technology that powers today’s cloud computing systems. Virtualization provides isolation as well as resource control that enable multiple workloads to run efficiently on a single shared machine and thus allows servers that traditionally require multiple physical machines to be consolidated to a single, cost-effective physical machine using virtual machines or containers. Due to virtual machine techniques, the strategies that improve performance like hardware acceleration, running concurrent virtual machines without the correct proper resource controls not used and correctly configured, the problems of scalability as well as service provisioning (crashing response time, resource contention and functionality or usability) for cloud computing, emanate from the configurations of the virtualized system. Virtualization performance is a critical factor in datacentre and cloud computing service delivery. To evaluate virtualization performance as well as to determine which virtual machine configuration provides effective performance, how to allocate and distribute resources for virtual machine performance equally is critical in this research study. In this study, datacentre purposed servers together with Type 1 (bare metal hypervisors), VMware ESXi 5.5, and Proxmox 5.3 were used to evaluate virtualization performance. The experimental environment was conducted on server Cisco UCS B200 M4 which was the host machine and the virtual environment that is encapsulated within the physical layer which hosts the guest virtual machines consisting of virtual hardware, Guest OSs, and third-party applications. The host server consists of virtual machines with one operating system, CentOS 7 64 bit. For performance evaluation purposes, each guest operating system was configured and allocated the same amount of virtual system resources. Various Workload/benchmarking tools were used for Network, CPU, Memory as well as Disk performance, namely; Iperf, Unibench, Ramspeed, and IOzone, respectively. In the case of Iozone, VMware was more than twice as fast as Proxmox. Although CPU utilization in Proxmox was not noticeably affected, considerably less CPU utilization was observed in VMware. While testing the memory performance with ramspeed, VMware performs 16 to 26% better than Proxmox. In the case of writing, VMware observed 31 to 51% better than Proxmox. In a network, it was observed that the performance on Proxmox was very close to the level of bare metal setup. The results of the performance tests show that the additional operations required by virtualization can be confirmed utilizing test programs. The number of additional operations and their type influence specifically to performance as overhead. In memory and disk areas, where the virtualization
procedure was clear, the test outcomes demonstrate that the measure of overhead is little. Processor and network virtualization, then again, was more perplexing. Hence the overhead is more significant. At the point when the overall performance of a virtual machine running in VMware ESXi Server is contrasted with a conventional system, the virtualization causes approximately an increase of 33% in performance.Because of the difficulty in providing optimal real system configurations, workload/benchmarks could provide close to real application systems for better results. The tests demonstrate that virtualization depends immensely on the host system and the virtualization software. Given the tests, both VMware ESXi Server and Proxmox are capable of providing Optimal performance.
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The development and practical implementation of a project management model for enhancing new venture creation successColeman, William. James. January 2014 (has links)
Thesis (M. Tech. (Business Admin.)) - Central University of Technology, Free State, 2014 / Research by the Global Entrepreneurship Monitor (GEM) continuously indicate that new venture creation success rate in South Africa is disturbingly low. This situation arises despite numerous support mechanisms in place to encourage citizens to establish their own businesses. This is an indication that current approaches to encourage new venture creation are not working. New approaches must therefore be found.
The goal of this study was to combine the processes of project management and entrepreneurship, two seemingly diametrically opposed management philosophies into an integrated process model that will contribute to enhancing the new venture creation process. So, at the heart of this study is the wish to assist prospective entrepreneurs in their new venture creation journey.
To achieve this objective, action research design, an emerging approach to qualitative research was adopted. Specifically, the canonical action research was used. Holistically, the study can be described as applied, cross-sectional, descriptive and exploratory in nature.
Through a series of iterative canonical action research cycles, a model was developed. The results suggest that despite their seemingly diametrically opposed management philosophies, an integrated project management model for new venture creation is achievable.
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A calculation concept to reduce manufacturing cost on laser sintering machinesStarz, Anton Johannes January 2008 (has links)
Thesis (M. Tech.) - Central University of Technology, Free State, 2008 / A company’s ability to produce products faster and more economically may lead to a competitive edge in the international market. The reduction of development costs and shortened development time will undeniably depend on effective organisational structures that are based on effective information- and communication techniques and manufacturing technologies. An innovative manufacturing technology that impacts on rapid product development is Rapid Prototyping (RP). The Centre for Rapid Prototyping and Manufacturing (CRPM) works closely with South African companies, supporting them with common mechanical engineering solutions and specialising in the manufacturing of prototypes. One of the options offered in the manufacture of prototypes is the Laser Sintering (LS) process. It is however, difficult to determine the product cost for the building volume used to manufacture the prototypes. Prototypes from different clients can be manufactured at the same time in the same process. The problem however, is how to calculate the costs for each prototype and to offer the clients an accurate quotation for the manufacture of the prototype. Therefore, it is necessary to design a calculation concept, which includes all accrued costs and allocate these to the different parts/prototypes. As it is problematic to calculate the manufacturing cost of prototypes, it is necessary to analyse all the effects, parameters and influences on the manufacturing process in order to determine the manufacturing time, and ultimately the machine costs. This is needed to calculate the total cost of one platform and the cost of each individual part. The project, through various experiments determined how to allocate the costs, through a correlation between part volume and platform height. The aim of the study was to determine a calculation concept to estimate the total platform cost and the cost of each individual part. Furthermore, the estimated cost was compared with the actual cost to determine the deviation between the calculation methods, and lead to a calculation concept that can be used to predict and reduce the manufacturing costs. The results obtained from the research were used for an exact calculation and reduction of prototype unit costs manufactured on LS machines, which gave three basic advantages:
* Manufacturing costs were reduced to benefit clients, which meant that they could invest more in the design of new prototypes and products, to improve customer satisfaction
* Prototype manufacturing on expensive RP machines could be optimised by using more prototypes and lower costs for entering the market.
* The calculation risk could be minimised, which lowered the risk of losing money on a project and resulted in better planning for available resources.
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Integration of a vision-guided robot into a reconfigurable component- handling platformViljoen, Vernon January 1900 (has links)
Thesis (M. Tech.) -- Central University of Technology, Free State, 2010 / The latest technological trend in manufacturing worldwide is automation. Reducing human labour by using robots to do the work is purely a business decision. The reasons for automating a plant include:
Improving productivity
Reducing labour and equipment costs
Reducing product damage
Monitoring system reliability
Improving plant safety.
The use of robots in the automation sector adds value to the production line because of their versatility. They can be programmed to follow specific paths when moving material from one point to another and their biggest advantage is that they can operate for twenty-four hours a day while delivering consistent quality and accuracy.
Vision-Guided Robots (VGRs) are developed for many different applications and therefore many different combinations of VGR systems are available. All VGRs are equipped with vision sensors which are used to locate and inspect various objects. In this study a robot and a vision system were combined for a pick-and-place application. Research was done on the design of a robot for locating, inspecting and picking selected components from a moving conveyor system.
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Evaluation of the swat model in simulating catchment hydrology : case study of the Modder river basinTetsoane, Samuel Tshehla January 2013 (has links)
Thesis (M. Tech. (Civil engineering)) - Central University of Technology, free State, 2013 / Hydrological models have become vital tools for understanding hydrologic processes at the catchment level. In order to use model outputs for tasks ranging from regulation to research, models should be scientifically sound, robust, and tenable. Model evaluation is therefore beneficial in the acceptance of models to support scientific research and to guide policy, regulatory, and management decision-making. The objective of this study was to evaluate the performance of the SWAT model in simulating stream flow for the Modder River Basin. The study area is situated at -29° 11’ latitude and 26° 6’ longitude at an elevation of 1335 m and drains a land area of 949 km2. The land cover is mainly grassland (pasture) with other minor land use types. The climate of the area is semi-arid with Mean Annual Precipitation (MAP) of 563 mm. Two techniques that are widely used in evaluating models, namely quantitative statistics and graphical techniques, were applied to evaluate the performance of the SWAT model. Three quantitative statistics, namely Nash-Sutcliffe efficiency (NSE), percent bias (PBIAS), and ratio of the mean square error to the standard deviation of measured data (RSR), in addition to the graphical techniques, were identified to be used in model evaluation. Results of calibration and validation of the model at a monthly time step gave NSE of 0.65, Pbias of 15 and RSR of 0.4, while NSE of 0.5, Pbias of 31 and RSR of 0.5 were recorded for validation. According to monthly model performance ratings, the model performed well during calibration and performed satisfactory during the validation stage.
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THE EFFECTIVE GOVERNMENT INFORMATION ACCESSIBILITY SYSTEM FOR A COMMUNITY IN THE REMOTE AREAS OF SOUTH AFRICAMkhonto, Mkhonto. January 2014 (has links)
Thesis ( M. Tech. (School of Information Technology )) - Central University of Technology, Free State, 2014 / The aim of this study has been to find out how the community in the remote areas of
South Africa access government information. The study is based on four villages, two in
the Northern Cape Province (Heuningvlei and Galeshewe) and two in Limpopo Province
(The Oaks and Finala). A quantitative design was used. Open and closed-ended
questionnaires were used to collect data from the community. Out of 200 questionnaires
distributed only 144 responses were received. Responses in the questionnaires were
tabulated, coded and processed using the Statistical Package for Social Sciences (SPSS) programme. Based on the analysis in Table 4.13, the study showed that 44 percent of the sampled community have access to information through Television which they classified as technology. Shortage of telecentres, distance to telecentres, age, lack of education, monthly income, infrastructure and transport cost were some of the important factors contributing to a lack
of access to information. Some of the findings are that most of the telecentres are located
far from towns, more than 7 kilometres from the village. Ideally, telecentres should be
located near the community, within a short walking distance. It is recommended that provision/establishment for easy access to information and communication services by the Universal Service and Access Agency of South Africa (USAASA) in the remote areas in the Northern Cape and Limpopo province is strongly considered for implementation. This will overcome the gap that exists between the urban and semi-urban communities regarding access to human rights information such as rights to life, equality, freedom of speech, assembly and access to information. It is also assumed that the implementation of telecentres and Internet Cafes, in order to facilitate the adoption of e-government information by people residing in remote areas (semi-urban areas) such as Heuningvlei, Galeshewe, The Oaks and Finala will contribute to better access to human rights. The study also recommends that the service costs charged by the
telecentre and Internet Cafes should not be expensive. This will assist the community to
afford to pay Internet services. Information is important for decision-making. For this reason, it is recommended that continued campaigns on awareness about the mportance of access to information through telecentres and Internet Cafes should be conducted.
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