Thesis (doctoral)--Universität Bern, 1916. / Includes bibliographical references (p. [5-7]).

Sasol biological sludge, coal fine and gasification ash were the three waste streams involved in this study. The main concern is that on their own they are not suitable as growth mediums, the ash is alkaline (pH>12) with high salinity (total dissolved solids of 8000 mg ℓ-1). Fine ash is microporous (particle size diameter <250 μm) and forms cemented layers that can restrict root growth while, gasification ash in macroporous (most particle size diameter ranged between 1 and 75 mm) and has a low water holding capacity. Sludge is unstable and can inhibit gaseous exchange. However, these wastes potentially, have physical, biological and chemical attributes that make them suitable as hospitable growth medium. Sludge can promote micro-fauna activity and, provide plant available nitrogen (N) as well as phosphorus (P) the ash is poor in. On a short term bases and in the long term it can also contribute to cation exchange capacity (CEC). Fine ash can increase water holding capacity and gasification ash can improve gaseous exchange. It was hypothesized that if the ash was treated with sludge, pH will be reduced to between 5.5 and 8, and weathering will reduce salinity to less than 400 mSm-1, increase CEC and increase plant available N and P. Therefore, the main purpose of this laboratory column study was to establish combinations of these waste streams that hold promise as plant growth media, based on various chemical and physical criteria link to hospitable plant growth media, as well as the influence of weathering on the release of essential plant nutrients. A total of 51 mixtures (each weighing 2.6 kg) were formulated based on wet mass basis and divided into 6 groups based on sludge content (0, 10, 20, 30, 40 and 50%) and packed into columns, subjected to wetting and drying for 1 year (10 wetting and drying cycles) by passing through deionized water equivalent to the pore volume and allowing the mixtures to dry in between. The leachates were analysed using Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES) and Kjeldahl procedures (for N release). Total elemental analysis was done using X-ray Fluorescence Spectroscopy (XRF) and acid digestion method. Particle size distribution was done using the sieve method. Cation exchange properties were assessed using ammonium acetate (NH4OAc), lithium chloride (LiCl) and potassium chloride (KCl) methods. Results indicated that sludge was critical for these mixtures,at a minimal content of 10% it increased the water holding capacity of the mixtures. In the mineralization of inorganic N at a lower limit of 20% sludgeenabled the production of plant available NH4+ and NO3- and less NO2-. Increasing sludge to 50% further reduced the production of NO2- in the mixtures. In terms of elemental release, mixtures without sludge were dominated by Na and the order of abundance was as follows; Na>K>Ca>Mg>P on mmol kg-1 but the introduction of sludge at a lower content limit of 10% changed the abundance of the elements as follows; P>Mg>Ca>Na>K on mmol kg-1. Sludge content as low as 10% reduced the pH of the mixtures to between 7.6 and 8 and EC to less than 400 mSm-1. However, increasing sludge to 50% increased the leachate EC dramatically and kept the EC high (415 mSm-1) till the end. Introduction of sludge at a low limit of 10 % content increased the CEC above 8 cmolc kg-1. The effects of fine ash on the water holding capacity of the mixtures were seen at the 10 % level, for example, mixture 13 with 10% fine ash had 0.3 mg kg-1, while mixture 12 with 0% fine ash had 0.27 mg kg-1. Increasing fine ash content above 40% increased pozzalanic properties, pH (>8), EC (>400 mSm-1), Na release and reduced CEC.Gasification ash is the biggest waste stream and utilizing these wastes as growth media will mean that it realistically will always dominate these mixtures. This study showed that on its own it will be a challenging environment. However, the amendent with sludge and fine ash resulted in some chemically and physically favourable changes in these media. It can be concluded that the main objective has been achieved and bio assay evalution of theses mixtures is recommended Copyright / Dissertation (MSc(Agric))--University of Pretoria, 2012. / Plant Production and Soil Science / unrestricted

Delays on electrical engineering projects are a phenomenon at Eskom distribution due to a wide range of causes. These project delays result in Eskom to contravene with Electricity Regulation Act 4 of 2006 in terms of providing efficient, effective and sustainable operation of electricity supply infrastructure, promoting the use of renewable energy sources and energy efficiency as well as to facilitate universal access to electricity for South African consumers (Gazette, 2006). Eskom strives to comply with the Electricity Regulation Act by initiating and implementing strengthening projects, refurbishment (reliability) projects, direct customer projects, infills projects and electrification projects (Eskom, 2014).The severe delays experienced in the delivery of electrical distribution projects have a negative impact on South African economic growth and population. This research study adopted interactive management methodology for the identification of project delay factors in Eskom distribution projects through the use of the idea writing technique, nominal group technique, and interpretive structural modelling technique. The interactive management methodology allows a group of people collaboratively to develop a structure that defines the relationship among the system elements. Using interactive management approach, a total of one hundred and twelve project delay factors were reduced to twenty six significant project delays which formed part of interpretive structural modelling. This research study revealed the hierarchical model illustrating interrelationships between the twenty six identified project delay factors. The research study identified three root causes of delays in electrical distribution projects at Eskom Northern Cape Operating Unit, namely "poor communication", "poor planning", and "project scheduling not properly done". The three identified root causes can be used as critical points for eradicating delays in electrical distribution projects at Eskom Northern Cape Operating Unit. The research study found that a total of ten out of twenty six project delay factors were unique to electrical distribution projects at Eskom Northern Cape Operating Unit.

Speed and measure of the fourth industrial revolution (Industry 4.0) is bringing about shifts in power, wealth and knowledge. For entrepreneurs, who are known to drive innovation, Industry 4.0 offers a wide scope of opportunities in the future. As a middle-income country, South Africa needs to use its knowledge and innovations to sharpen its innovative edge in order to compete globally and stimulate innovation. Hence, this research attempts to determine the relationships between entrepreneurial competencies, entrepreneurial absorptive capacity and innovation capacity. Three conceptual frameworks of the interrelationships between these constructs were synthesised from the literature. As ample research on entrepreneurial competencies is widely available, a Delphi study was employed, together with a concept matrix to determine which entrepreneurial competencies should be included specifically significant for innovation within the 4IR context in South Africa. Four entrepreneurial competency categories emerged: cognitive (knowledge), functional (skills), social (attitudes and behaviours) and meta (facilitating learning) categories. Using a survey method, the analysis on a sample of 452 innovative entrepreneurs in South Africa was mainly done by empirically testing the causal linear relationship through structural equation modelling (SEM). Furthermore, an Artificial Neural Networking (ANN) technique which tests non-linear relationships and develop pattern recognition as well as modelling was conducted to compare the results of a non-linear relationship with those of a linear relationship. However, explorative comparisons of the performance of linear SEM models with non-linear NN indicated that the SEM models in this case performed better in explaining the variance in the dependent variables than did the ANN. Through the theories of innovative performance, person-entrepreneurial fit and knowledge spillover, the findings of the study indicate the importance of incorporating a unified entrepreneurial competency typology perspective on innovation. The cognitive, functional, social and meta competencies as well as entrepreneurial absorptive capacity are significant predictors of innovation capacity. The implications of this extend to transmitting knowledge through absorptive capacity, which allows entrepreneurs to identify and exploit opportunities, identified from new knowledge sources and incorporated into new innovations. Additionally, entrepreneurial absorptive capacity mediates the relationship between social, meta, and functional competencies and innovation capacity. Entrepreneurial absorptive capacity was also found to be a moderator between cognitive competencies and innovation capacity. Therefore, the development of certain entrepreneurial competencies, significant for innovation, is crucial for improving the strength of the relationship between entrepreneurial absorptive capacity and innovation capacity of entrepreneurs. These results have important implications for Industry 4.0 entrepreneurs, educators, policy makers as well as entrepreneurship models. / Thesis (PhD (Entrepreneurship))--University of Pretoria, 2020. / Business Management / PhD / Unrestricted

Semi-rigid composite connections with precast hollowcore slabs are a newly developed technique with few applications in current construction practice. The research on the structural behaviour of this new type of connection is limited, with no existing method available to predict its important characteristics such as moment and rotation capacities. In this paper, based on the parametric studies of the three-dimensional finite element model and full-scale tests, analytical methods to calculate the moment and rotation capacity of this type of composite joint are proposed. A comparison between the proposed calculation method and the full-scale test results was made, and good agreement was obtained.

Yes / Reliable health information is essential for decision making in the healthcare system. Information management in Kenya was considered the weakest area under the Health Information System pillar mainly due to inadequate health workers capacity. The study therefore aimed at assessing health workers skills and current training needs for information management in the selected healthcare facilities. Cross-section research design was adopted and both purposive sampling technique and censuses were used to establish the study participants. Analysis was done using SPSS version 20 and results were presented in tables, charts and graphs. It was established that capacity building was usually undertaken through on-job trainings i.e. 85.1% (103) health workers had on-job training on filling of data collection tools and only 10% (13) had received formal classroom training on the same. Further, only 9.1% (11) health workers had received information management training while 90.9% (110) had not received such training. Health workers demonstrated below average skills on information management i.e. only 17.4% (21) could check for data accuracy, only 16.5% (20) could compute trends from bar charts and only 16.5% (20) could transform the data they collected into meaningful information for use. The researcher recommended that healthcare facilities management teams develop a competency based framework for defining the desired skill mix for information management and have a yearly Training Needs Assessment for assessing training needs for information management among the health workers.

Syftet med den här studien var att undersöka på vilket sätt vården i Västerbottens läns landsting nyttjar den kompetens som vårdadministratörer besitter efter att ha blivit examinerad från det Vårdadministrativa programmet vid Umeå universitet. Den syftade även till att studera hur vårdadministratörer bedömer förändringsmöjligheter som kan tänkas finnas för deras yrkesgrupp idag. Studien baserades på kvalitativa semistrukturerade intervjuer som genomfördes med till antalet åtta anställda inom Västerbottens läns landsting som alla gått det vårdadministrativa programmet på Umeå universitet. Undersökningen resulterade i en sammanställning av arbetsuppgifter som förkom i varierad frekvens i informanternas arbete, samt tre innehavda befattningar där läkarsekreterare är den klart vanligast förekommande bland informanterna. Studien visade också att den studerade yrkesgruppen bedömde personliga egenskaper snarare än utbildning som avgörande i att utveckla och förändra yrkesgruppens förutsättningar, arbetsuppgifter och titulatur. Det framkom också att det är svårt att utveckla vården i sig och att maximera användandet av intern kompetens då tidpress, brist på personal och hög arbetsbelastning försvårar nya kreativa lösningar och idéer från medarbetarna.

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published_or_final_version / Computer Science / Doctoral / Doctor of Philosophy

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