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The Impact Of Need For Achievement (N-Ach) And Personality On Human Resource Strategies Among Sme Owner-Managers
Get PDFDissertationThe objective of the study was to determine whether n-Ach and Personality are determinant factors in the adoption of human resources strategies, among small businesses in the Mangaung Metropolitan area. Using descriptive, research design, a population of 390 owner/managers of registered small businesses in the Mangaung Metropolitian area were sampled. The sample size for the study was calculated as follows: Confidence interval: 95%; Population: 390; Margin error 5% and the determined sample size for the study was, therefore, 194 SME owner-managers. Data was collected using a self-administered structured questionnaire, with items measured on a Likert scale of (1) Strongly Disagree to (5) Strongly Agree. Data analysis for this study was done using descriptive and inferential statistics. The findings of the study revealed that personality and n-Ach influence owners of small businesses to adopt an HR Strategy. The results further revealed that personality has a mediating effect on the relationship between n-Ach and HR strategy
Design And Evaluation Of Wireless Technology Systems For Data Analysis
Get PDFDissertationThe internet and cloud storage are becoming increasingly important to researchers, hobbyists and commercial developers. This includes the transmission of reliable data as the availability and functionality of remote sensors and IoT devices are becoming more common. The availability of high-speed internet connections, like fibre-optic cable, LTE and digital radios, changed the playing field and enabled the user to transmit data to cloud storage as speedily as possible.
With these various technologies available, the question now arises: Which technology is more reliable and efficient for IoT sensors and for users to transmit data to a cloud server? This project aims to investigate the reliability and transmission delay of transmitted data from Wi-Fi, GPRS Class 10, and digital radio networks to cloud storage. A sampling unit was designed to evaluate analogue inputs periodically and send the recorded data to the three technologies under test. It also records the data to an on-board micro SD card along with an indexing system. The systems then transmit the sampled data and index number to a cloud storage server via the communication technologies under test. The cloud-stored data is then compared with the recorded data of the sampler unit to determine data integrity.
The transmission delays can be calculated by using the cloud storage server’s time stamp information and the original time stamp of each data message. From the results acquired in the research, it showed that digital radio is a very reliable and stable means of data communication but it lacks direct connection to the internet. Although, both Wi-Fi and GPRS Class 10 are permanently connected to the internet, it was also observed that Wi-Fi internet connectivity may be susceptible to interference from external factors like the continuity of supply from the national power grid and from load shedding. It also showed that the XBee digital radio system lost 0.21% packets compared to the 0.31% for Wi-Fi and 1.46% for GPRS Class 10. On the other hand, although GPRS Class 10 may be a bit less reliable than digital radio and Wi-Fi, it is relatively cheap to use and has the ability to connect to multiple communication towers for communications redundancy. The outcome of this research may help researchers, hobbyists and commercial developers to make a better-informed decision about the technology they wish to use for their particular project
Contamination Of Groundwater By Potential Harmful Elements From Gold Mine Tailings And The Implications To Human Health: A Case Study In Welkom And Virginia, Free State Province, South Africa
Get PDFArticleMining of gold in the Welkom and Virginia areas of the Free State Province in South Africa has produced
numerous gold mine tailings, which contain a variety of contaminants. The extent of contamination of
groundwater in the area was studied by measuring several water quality indicators at eight sampling sites, and
within three zones. The overall contamination of groundwater was quantified by computing a Drinking Water
Quality Index (WQI). The results revealed that majority of the groundwater in the Welkom and Virginia areas is
unsuitable for drinking, as confirmed by high WQIs. At only three sites was the water samples suitable for
drinking. One site revealed water to be of very poor quality, while the remainder 40% of the sites indicated water
to be of poor quality. The high indicator microbiological counts also affirmed the poor quality of the groundwater.
Faecal coliform bacterial counts were 100% non-compliant to drinking water quality limits when
compared to the World Health Organization and South African National Standard on Drinking Water 241, while
E. coli counts exceeded both the drinking water quality limits at 50% of the sampling sites. Of the potential
harmful elements analysed, Pb and Fe were found to be at toxic levels. For Pb, 40% of the water samples
exceeded the drinking water quality limits while 63% of water samples were non-compliant for Fe. This result
exposes the poor quality of the groundwater in the Welkom and Virginia areas, which poses a serious threat to
the health of the local people, as groundwater is their primary source of drinking water. This research highlights
the urgent need for mitigation measures to be introduced by the local authorities to improve the quality of the
groundwater in the study area
Transforming South Africa’s Universities of Technology: A Roadmap Through 4IR Lenses
Get PDFArticleSince their birth in the 6thcentury, universities have undergone different forms oftransformations, especially of structural, ideological, and epistemological nature. Recently, theemergence of the fourth industrial revolution (4IR) has triggered a wave of suchtransformations and just like other industrial revolutions, university management ought to becautious as such transformations could exacerbate existing inequalities between the rich andthe poor students. To this end, a clear roadmap for such a transformation becomes critical.This is the contribution of this paper. We achieve this through a bibliometric analysis of thestate of scientific research into the ‘university transformation’ topic, with a special focus onSouth Africa’s (RSA) context. The content of the identified scientific publications on RSA wasfurther subjected to thematic analysis leading to the revelation that decolonisation,community engagement and structural transformation, are the main research themes. It alsoemerges that RSA universities have not embraced 4IR as a lens through which to pursuetransformation. On the other hand, the RSA government launched the project:“Transformation at Public Universities” during the 2017/18 planning year. Subsequently, alluniversities in the country adopted and rolled out a customised transformation agenda.Among these universities, are the six universities of technology (UoTs), which, for historicalreasons, the transformation project presents unique challenges and opportunities. Createdslightly after the millennium, UoTs are still seen as critical role players in the third missionof universities, that of “achieving economic growth and social progress”. These findings, aswells as the existence of systemic exclusion, marginalisation, and discrimination (especiallyalong racial lines) in RSA universities, defines our proposed roadmap. Using one of the UoTsand Massive Open Online Courses (MOOCs) as the reference, the proposed universitytransformation roadmap is supported by empirical data on the assessment of the readiness ofstudents to adopt 4IR technologies
Performance Evaluation of Power Differential and Sensitivity Based Protection for Active Distribution Systems
Get PDFArticleProtection performance is characterized by qualities
that include selectivity, speed, sensitivity and stability. Generally,
selectivity and speed present conflicting requirements on the
protection design, as do sensitivity and stability requirements. The
integration of distributed generation (DG), in particular at the
distribution level, further compromises satisfactory achievement of
these performance qualities. A recent paper by the authors
introduced a protection algorithm based on active power
differential and sensitivity analysis (APdSA) for the protection of
active distribution systems and microgrids. This paper investigates
the performance characteristics of this algorithm with respect to
selectivity, sensitivity, stability, and speed. It is shown that, with
an important modification to the protection zoning arrangement,
the APdSA algorithm is able to selectively clear faults in a DGintegrated
distribution system with high sensitivity, stability, and
speed, with more than 95% reach over a wide range of fault
resistances. The algorithm is also tolerant to
communication failure
The Influence of Non-Engineered Municipal Landfills on Groundwater Chemistry and Quality in Bloemfontein, South Africa
Get PDFArticleThis study assessed the groundwater quality around two municipal solid waste landfill
sites, in the city of Bloemfontein, Free State Province, South Africa. The two landfill sites are located
in two contrasting geological terrains, with both lacking some basic facilities found in a welldesigned
landfill. A total of eight groundwater samples were collected from pollution monitoring
boreholes near the two landfill sites, with five samples representing the northern landfill site and
three samples representing the southern landfill site. The samples were collected in the autumn and
winter seasons to assess any possible seasonal variations. They were analysed for physicochemical
(pH, electrical conductivity (EC), total dissolve solids (TDS), chemical oxygen demand (COD) and
total organic carbon (TOC)) and microbiological parameters (Escherichia coli, total coliform). The
results of the analysis showed that the waters from both landfills were generally dominated by Ca,
Mg, SO4, and HCO3 ions. Some of the major anions and cations in the water samples were above
the South African National Standard (SANS241:2015) and World Health Organisation (WHO)
permissible limits for drinking water. Majority of the boreholes had total dissolved solids and
electrical conductivity values exceeding the SANS 241:2015 and WHO permissible limits. Piper
trilinear plots for the two landfill sites showed that Ca(Mg)HCO3 water type predominates, but
Ca(Mg)SO4 and Ca(Mg)Cl were also found. These water types were further confirmed with
expanded Durov diagrams, indicating that that the boreholes represented a water type that is
seldom found which is undergoing ion exchange, typical of sulphate contamination. From the SAR
diagrams, boreholes in the northern landfill site had a high salinity hazard with only one borehole
in the southern landfill site having a high salinity hazard. The geology was found to play a
significant role in the distribution of contaminants into the groundwater systems in the study area.
The study concluded that the northern landfill site had a poorer water quality in comparison to the
southern landfill site based on the analysed physicochemical parameters. However, the southern
landfill site showed significant microbial contamination, due to the elevated amount of E. coli and
total coliform concentrations. The high permeability of the weathered dolerites in the northern
landfill site might have enabled the percolation of contaminants into the groundwater resulting in
the poorer water quality
Using WhatsApp for co-creation of learning resources: A case of a South African university
Get PDFResearch ArticleAlthough culturally diverse students have potential to create enriched learning resources, it is difficult to harness students’ agency and to aggregate individual contributions into a meaningful learning resource. This is one of the challenges facing higher education institutions in South Africa where institutions are increasingly cosmopolitan and culturally diverse, but production of knowledge has largely remained skewed in favour of those students with unlimited access to learning resources, the Internet and peer networks, anywhere, anytime. Although the appropriation of emerging technologies such as mobile phones has enabled a digital sharing culture, this social practice has not been harnessed for co-creation of learning resources. This article reports on a study that sought to uncover the extent to which the use of WhatsApp-enabled phones facilitated the co-creation of learning resources in a human resource management programme at a university of technology in South Africa. The article employed Amartya Sen’s capabilities framework to analyse WhatsApp interactions of 72 participants from underprivileged backgrounds. The article concludes that leveraging students’ capabilities, including rich culturally diverse knowledge, is not a mere outcome of access to a tool such as WhatsApp, but requires pedagogical designs that exploit the affordances of the tool
A Review of Methods Used to Reduce the Effects of High Temperature Associated with Polyamide 12 and Polypropylene Laser Sintering
Get PDFArticleThe polymer laser sintering (PLS) process is one of the most promising additive manufacturing (AM) technologies for polymeric
materials. However, the technique has challenges because the physical, mechanical, and chemical properties of the polymeric
powder deteriorate due to the high temperatures prevailing in the build chamber during manufacture. These high temperatures
cause agglomeration of powder, which leads to a decrease in the flowability of powder. There is also a related drop in the
coalescence of the powder granules during PLS, which results in porosity that undermines the mechanical integrity of printed
parts. Moreover, the viscosity of the melt increases due to cross-linking of molecular chains. This, in turn, increases the tensile
strength of the printed components at the expense of the percentage elongation at break. Thus, high prolonged processing
temperatures decrease the reusability of polymeric materials used in PLS. In this paper, a review of the studies conducted to
investigate ways of reducing the effects of high temperature on polymeric powders is presented
Generating a High Resolution Climate Scenario Through Regional Climate Modelling Over Part Of Southern Africa
No full textArticleGenerating a high resolution climate scenario using regional climate models is highly useful to study climate
change. Southern African like other global regions is prone to climate extremes and needs better investigation and
understanding. This article, therefore, demonstrates the usefulness of downscaling large scale climate scenarios over
this region for climate change impact studies. Four experiments were conducted to downscale the GCM HadGEM2-ES
model under three climate scenarios, namely the baseline, and Representative Concentration Pathways (RCP) 4.5 and
8.5. The predictions under both RCP4.5 and RCP8.5 climate scenarios indicate that seasonal rainfall will increase in
magnitude by 1 to 65% and 1 to 37%, respectively. The coverage area with increased rainfall varies from 33% to 77%
and 49% to 58% for RCP4.5 and RCP8.5, respectively. Temperatures are also predicted to increase under RCP4.5 and
RCP8.5. In general, the results are indicative of the potential future climate change impact in the region and may be
used for devising adaptation and mitigation strategies
Sustainable Groundwater Management Through Modelling Of Selected Hydrological Parameters: A Case Study Of The Modder River Catchment Of South Africa
Get PDFThesisFarmers and water users in arid and semi-arid zones of South Africa have a limited number of water resources. With 98% of South African surface water already allocated and committed, there is an increasing demand for use of groundwater through the use of wells and boreholes.
This study was carried out in the Modder River catchment, which is a sub-catchment under the larger Orange River system. increased population growth and increasing urbanisation have negatively affected water resources in the Modder River catchment since 2000. The population of the Modder River catchment increased from 618 566 in 2001 to an estimated 1 083 886 in 2016. This resulted in increasing water demand and excessive pumping of groundwater, particularly for agriculture and drinking water. At 351 million litres, the Bloemfontein area and Modder River catchment has the highest demand for water in the Upper Orange River Catchment.
Other negative effects are increased degradation of the environment, high levels of human-induced climate changes, and high variability of the natural climate. The net effects have been depletion of aquifers and prolonged periods of drought, which points to a lack of effective groundwater resources management tools and laxity in monitoring groundwater as a resource. Globally, the general trend is to adapt models and artificial intelligence to manage water resources sustainably. Groundwater sustainability models that incorporate artificial intelligence, may be used to enhance the governance of aquifers. Lack of such models is what motivated this research. This was achieved through the development of groundwater sustainability models/indices and information communications technology-based framework for groundwater monitoring that makes use of artificial intelligence to reach informed decisions for improved groundwater management.
The research was guided by a theoretical framework design, which included sustainability modelling of the interactions of the elements and physical processes linking the hydrological cycle with human instigated factors in connection with groundwater. These interactions were climate and utilisation of groundwater, surface water-groundwater water linkages and climate–groundwater interaction connections in hydrological parameters. The parameters were weighted and scored and included precipitation, slope, vegetation cover, evapotranspiration, climatic zones, water quality, aquifer yields, soil composition, aquifer sustainability, population, water use categories, the permit framework and groundwater rights. These parameters were grouped into the following; Factor A: climate, Factor B: rights and equity versus resources, Factor C: socio-economic matters and Factor D: aquifer sustainability. Delphi techniques of scoring and rating were applied. Scores were assigned with the lowest scores of one relating to poor practices and the highest score of five relating to adequate practices. Climate (Factor A) and aquifer sustainability (Factor D) were summed up to an aggregate score of 30 each, while rights (Factor B) and socio-economic aspects (Factor C) had separate scores of 20 each. The groundwater sustainability range had 19 (slightly reasonable) and 100 (profoundly feasible) scores.
The developed sustainability indices were applied to 51 boreholes in the Modder River catchment of South Africa, for which consent was obtained for the study. These boreholes were both government and private boreholes. ArcView GIS was used to demonstrate the results for each factor for the 51 boreholes towards the groundwater sustainability concept. The sustainability class in the Modder River Basin ranged from low to moderate sustainability. The results showed that only 11 boreholes were sustainable, implying that they were reasonably maintainable. The other 40 boreholes had low sustainability scores, which indicated that they were not sustainable. The moderate sustainability class was typical of areas with extensive dolerite, low slopes, and low recharge.
In order to validate the results, plots of over 70 years of rainfall data and evapotranspiration data of the Modder River Basin catchment were generated. This was to indirectly account for a mini-water balance and how much was available for groundwater recharge. It was found that rainfall was significantly lower than evapotranspiration, which meant there was more evapotranspiration than recharge for long periods of time. The Modder River catchment received its highest bout of rain in 1971/1972. The sustainability maps showed areas with low sustainability scores correlating with areas with a low aquifer sustainability factor since low recharge related to the low sustainability scores.
A further validation analysis was carried out on the final sustainability map, the river network map and recharge map of the study area, as extracted from the countrywide recharge map of South Africa. High groundwater recharge areas (over 34 mm) were found in the eastern and south-eastern parts of the study area. These areas corresponded with high river network presence. The central and western parts of the study area were marked by lower groundwater recharge values (below 12 mm). This was consistent with the derived sustainability final index maps. There was a high correlation between the sustainability index map, the drainage basin map and the recharge map. The final sustainability map value was plotted against measurable parameters (pumping rate, aquifer yield). In this thesis, a calculation of the correlation coefficient values was low at 1.04%, indicating no positive correlation or reinforcement. In addition, the plots of the comparison of the calculated indices with the measured physical values on one hand, and an analysis of the actual end users’ validation done to assess the ability of the sustainability index on the other hand, were presented as the final sustainability map value against a measurable parameter storativity (aquifer yield). For this, significant similarity between the storativity plot and the sustainability index map was observed.
Furthermore, the results showed that the ideal pumping rate should be 138 080 cubic metres per year per borehole. This means that only this amount may be pumped, without disturbing the dynamic equilibrium of the aquifer. This pumping rate would support the capture principle approach for the C52 catchment. Currently, the average pumping rates is higher than the aquifer yield. The majority of the points on the major plotted graphs were below the best fit line. This meant that the boreholes were abstracted at a rate that was higher than the aquifer yield. With this finding, the researcher calculated and recommended pumping rates/volume of water for each borehole. This meant that only that amount may be pumped without disturbing the dynamic equilibrium of the aquifer. This pumping rate would support the capture principle approach for the C52 catchment. The recommended pumping rates were based on applying the corrected formula: Pumping rate = 157 397x + 138 080, which was derived after the pumping rate analysis. The recommended pumping rates were proposed because the moderate to low classes represented areas that were the opposite of a favourable scenario: overly high abstraction activity, unfavourable climatic conditions, and slow to little groundwater processes and interactions (high or steep slopes and low rainfall).
From the graph of storativity versus licensed volume that was plotted, this research revealed that higher volumes were licensed, compared to the storage volume of the aquifer. The findings on the final sustainability map provided in this thesis further correlated to this. There was no correlation between the pumping rate/licensed volume and the storativity of C52.
The findings above confirmed the widely documented challenges of groundwater monitoring in the southern African region that most of the water administrative authorities continue to face. One of the reasons is that many water clients do not submit the required compulsory critical data for effective monitoring of water use. This, combined with the absence of limits by water authorities regarding boreholes dug by permit holders, has led to difficulties in decision-making and groundwater conservation. To address this, the potential of artificial intelligence in groundwater management is explored in this research. A framework that makes use of artificial intelligence in groundwater management is proposed. The aim of this framework is to increase the success chances of groundwater management, conservation, and sustainability by means of a monitoring system through real-time updates and early warning signals to water management, and to, thus, reinforce positive behavioural practices on water abstraction and effective water usage. With this, groundwater consumers will have the means to gauge when they are using too much water and municipalities will have the means to gauge if a catchment is over-abstracted. The net gain or impact will be water savings, cost savings and preferable performance of provinces, municipalities and departments that manage water. Besides, once implemented, this framework would ensure automation of the sustainability modelling of groundwater system discussed in the thesis. This would result in an efficient catchment monitoring, allocation, licensing, and characterisation for an effective groundwater management system