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Developing the Usage Index for Teaching with Technology: A Case Study for Motheo District, South Africa
Get PDFArticleVirtual reality has taken the world by storm over the past decade where learners are allowed
to gain experiences that are not possible with ordinary teaching methods. The interactive
technological devices such as GeoGebra have made Euclidean geometry easy to understand
by learners. The current study aimed to investigate the use of technology in the teaching of
Grade 12 Euclidean geometry. This study used a four-dimensional model for teaching with
technology in the investigation. All responses were averaged and normalised to produce an
index for the measurement of the effective technology use in teaching of Euclidean geometry
in Grade 12. The learning style of students contributes significantly to the use of technology
in classes, particularly the audio-visual learning style. Bloemfontein showed a high number
of learners ready to be taught through technology. However, this is in opposition to the
teachers in terms of their age groups and enthusiasm to use technology. In Botshabelo and
Thaba Nchu areas that were previously resource-disadvantaged, the current government has
ensured that technological teaching resources are available where unfortunately their usage
is not satisfactory, ranging from ‘maybe used’ to ‘less use of technology’ in teaching of
Euclidean geometry in classroom. The authorities are therefore advised to hold technology
workshops for senior teachers, reduce class sizes and tighten security in schools to avoid
connecting and disconnecting of technological devices from one classroom to another to
avoid wastage of teaching time
Optimal Power Dispatch in a Multisource System Using Fuzzy Logic Control
Get PDFArticleThe rising of hybrid system controllers, in real-time renewable energy for the optimum energy management system (EMS),
required the design of a real-time controller to operate the entire system in real time. The increasing popularity of Renewable
Energy (RE) has a control strategy, that determined the overall efficiency of the hybrid system (HS), although the energy
management system of these systems is particularly complex to be managed. The paper’s main contribution is to investigate
the feasible controller and, later, to present an advanced control strategy for managing and controlling the flow of hybrid
renewable energy (HRE) with a diesel generator (DG) and battery (BT) as a backup in rural application of South Africa
(SA) . EMS was implemented using a fuzzy logic controller (FLC) in MATLAB/SIMULINK. This study analysed input and
output variables for the design of a controller, with a set of rules and a three-dimension (3D) surface. Simulated results are
similar studies conducted between previous years and now, however, they differ in their objectives. A Fuzzy Logic Controller
(FLC) was considered as the most suitable option to be used to control the entire system and further demonstrated acceptable
performance in managing the power flow between the sources under various loads demands, while at the same time storing
excess energy in the battery. This study finally answers the question of the feasibility of the controller in real-time applications.
However, further investigation is to be conducted, to establish further results in real time, through the programmed FLC for
smooth performance in hardware-in-the-Loop (HIL) test equipment
The Knowledge, Attitude, And Practices Of Food Handlers In Central South African Hospices
Get PDFArticleThe escalating number of foodborne diseases and food poisoning outbreaks demand a better call for improved food-handling practices. Hospices are typically described as nongovernmental organizations that offer palliative care to terminally ill patients. The majority of hospice food handlers are not trained in food safety aspects, and services are offered on a voluntary basis. In this study, a descriptive survey design comprising of semistructured questionnaire was utilized to assess the knowledge, attitudes, and practices of the hospice food handlers (n = 100) in hospices around Central South Africa. More than half of the participants (68%) had not taken basic food safety training. The average percentage of the correct answers on the knowledge questionnaire was 66.8%. The participants had a mean age of 35 years (SD = 9.27). Attendance of food safety course had a significant effect on both the practices of using gloves to touch or distribute unwrapped foods (χ2 = 8.411, p-value = .012), and washing hands after using gloves (χ2 = 12.560, p-value = .001). The overall KAP mean score was 78.38. A statistically significant difference was found between the trained and untrained food handlers regarding food safety knowledge (p < .001). There was substantial lack of knowledge regarding the correct temperature for a refrigerator including hot ready-to-eat food
Methodological Approach For The Compilation Of A Water Distribution Network Model Using QGIS And EPANET
Get PDFArticleThis paper presents the development of a methodological approach based on the integration of free-of-charge open-source software, e.g. QGIS and EPANET, and engineering practices applicable to water distribution network design. The use of QGIS and EPANET, as well as the integration thereof with sound engineering practices and judgement, proved to be both viable and practical to enable practitioners to create a water distribution network model of an existing network in smaller developments or towns. Typically, in the latter smaller developments or towns, the professional cost associated with the additional time required when commercial licensed software is used, could be lower than the actual cost associated with the procurement of the licensed software itself. Hence, the developed process flow diagrams will not only potentially save time and money in comparison to a traditional, manual approach in EPANET, but will also provide guidance to practitioners and assist smaller municipalities in southern Africa facing challenges in terms of outdated records and budget constraints. It is envisaged that the implementation of the overall methodology will contribute to improved water infrastructure planning, design and management, especially in the southern African context where water resources are scarce and service delivery remains a pressing issue
Conceptualizing Sustainability Governance Implementation for Infrastructure Delivery Systems in Developing Countries: Success Factors
Get PDFArticleInfrastructure delivery processes possess the potential to negatively influence sustainability.
To curb the incidence of these processes within infrastructure delivery systems, the enthronement of
an e ective project management and governance framework becomes imperative. This led to the
emergence of literature on sustainable project management practice. However, studies seeking to
modify existing project governance structures in like manner remain limited. This study contributes
to this emerging discourse on the utility of project governance competencies in facilitating sustainable
infrastructure delivery. To achieve this objective, this study identifies critical success factors central to
the design of e ective sustainability governance structures of a typical infrastructure delivery (ID)
system with the assistance of a cybernetic system framework—the viable infrastructure delivery
systems model (VIDM). Adopting a qualitative multi-case study research design, this study deploys
semi-structured interviews for data elicitation through purposively sampled interviewees within
the identified cases and a document review. Qualitative content analysis (QCA) was deployed for
data analysis. Findings from this study provide success factors for designing e ective sustainability
governance structures for ID systems. It is expected that the findings from this study will contribute
to the emerging discourse concerning sustainability governance of ID systems
Using Historical Data To Explore Transactional Data Quality Of An African Power Generation Company
Get PDFArticleBackground: In developing countries, despite large public companies’ reliance on master data for
decision-making, there is scant evidence to demonstrate their effective use of transactional data
in decision-making because of its volatility and complexity. For the state-owned enterprise (SOE)
studied, the complexity of generating high-quality transactional data manifests in relationships
between customer call transactional data related to an electricity supply problem (captured by
call centre agents, i.e. data creators) and technician-generated feedback (i.e. data consumers).
Objectives: To establish the quality of customer calls transactional data captured using source
system measurements. To compare this data set with field technicians’ downstream system
transactions that indicated incorrect transactional data.
Method: The study compared historical customer calls transactional data (i.e. source system
data) with field technician-generated feedback captured on work orders (i.e. receiving system)
in a power generation SOE, to ascertain transactional data quality generated and whether field
technicians responded to authentic customer calls exclusively to mitigate operational expenses.
Results: Mean values of customer call transactional data quality from the source system and
technician-generated feedback on work orders varied by 1.26%, indicating that data quality
measurements at the source system closely resembled data quality experiences of data
consumers. The SOE’s transactional data quality from the source system was 80.05% and that
of historical data set from evaluating feedback was 81.31% – percentages that exceeded average
data quality measurements in literature.
Conclusion: Using a feedback control system (FCS) to integrate feedback generated by data
consumers to data creators presents an opportunity to increase data quality to higher levels
than its current norm
Does the Interpersonal Dimension of Goleman’s Emotional Intelligence Model Predict Effective Leadership?
Get PDFArticleThe purpose of the study is to examine the relationship between social
awareness and relationship management as the interpersonal dimension of
Goleman’s emotional intelligence and their ability to predict effective leadership
in the Ghanaian banking industry. Using a descriptive cross-sectional survey
design, a sample size of 307 employees was determined for the study from six
commercial banks selected from Ghana’s Club 100 rankings. A multi-stage
sampling technique was used in the selection of the banks, their branches and
employees who participated in the study. Standardized questionnaires served as
the instruments for data collection. Hierarchical multiple regression analysis
was used to analyze the data. A significant positive relationship exists between
social awareness and leadership effectiveness as well as relationship
management and leadership effectiveness. The results also showed that
demographic variables (gender, age, educational level, tenure) significantly
moderated the relationship between social awareness and leadership
effectiveness as well as relationship management and leadership effectiveness
Assessment of theMineral Composition of Heaving Soils Using Geotechnical Properties
Get PDFArticleThe behaviour of heaving soils is generally governed by the matric suction. Nonetheless, the mineralogical characteristics influence the geotechnical behaviour. X-ray diffraction is a common technique used to determine the mineral composition. This equipment is costly and the process time-consuming. The objective of this research is to develop predictive mathematical models to determine the predominant minerals in heaving soils. Soil samples are collected from identified areas across Free State province by digging at 50 cm depth from the ground surface. Geotechnical lab studies such as particle size distribution, Atterberg limits, specific gravity, free swell ratio, free swell index, linear shrinkage, and X-ray diffraction are performed to evaluate soil properties. A stepwise analysis is conducted to determine the response of each type of mineral to soil properties, and select the best subsets. Moreover, the influence of soil minerals on soil properties is achieved by investigating the correlation between the relevant soil properties and each mineral. Multivariate regression is performed utilizing MINITAB 18 program to develop mathematical predictive models. These equations are assessed base on correlation coefficient, probability value (P-value), and standard residual pattern analysis. The predominant minerals can be assessed with acceptable accuracy utilizing the proposed semi-empirical models
Feasible Use Of Recycled Concrete Aggregates As Unbound Road Base Material In South Africa
Get PDFDissertationSustainability is one of the biggest challenges facing the world today. Construction and demolition waste (C&DW) has become a financial burden globally. Landfills are reaching maximum capacity earlier than expected and one of the biggest contributors to this phenomenon is C&DW. This is generated by the need for new infrastructure, refurbishment and demolition of existing infrastructure as a result of urbanisation that is sweeping through the world. New avenues have to be explored to reduce the financial costs and environmental effects instead of the old-fashioned way of hauling C&DW to landfills.
There is uncertainty with regards to defining CD&W in the world: every country has its own definition, and there is no exact amount available for the total of CD&W generated worldwide. The composition of C&DW varies based on site activity and is, usually, mainly made up of concrete. The United States alone generates about 100 million tons annually of C&DW, and roughly more than 50% of the landfill volume is used for C&DW. About 5 to 8 million tons of C&DW is generated annually in South Africa, where the community is not keen to recycle and few organisations are involved in recycling.
C&DW is produced by crushing and screening of material from old infrastructure and may be produced by processing the material on site or off-site. There are mobile processing machineries available in the market which gives flexibility to production of C&DW. The material is crushed and screened for production and there is technology available to assist with the removal of detrimental substance and steel.
The recycling of C&DW is still in its early stages. Although the European Union and several American States have high expectancy in C&DW material as a commodity, it took ISO 9000 until 1996 to come up with standards for recycled material. In South Africa there are currently no local standards for C&DW and there is consequently a need to develop standards to promote the use of C&DW. The introduction of standards will give environmental value to the construction industry and eradicate financial losses, and will also assist to overcome barriers.
The South African experience regarding C&DW is not totally different to the world. The South African construction industry is not keen to recycle and uses mainly virgin aggregates from natural reserves. There are some similarities such as differences among local authorities with regards to the definition of C&DW. Most local authorities define C&DW as a waste generated through demolition, excavation and building activities. The Environmental Conservation Act, Act 73 of 1989, and the National Water Act, Act 36 of 1998 define waste as unwanted or surplus material, with potential to create pollution. The South African construction industry views the restrictive definition of waste as one of the barriers for implementation of recycling of C&DW. The C&DW in South Africa is mainly made of concrete. The concrete industry comprises cement manufacturers, aggregates producers, admixture suppliers, cement extender suppliers, precast and readymix concrete producers, structural engineers, building contractors and small-scale concrete consumers such as home builders. This use of virgin aggregates has adverse effects on the environment. It also leads to more extraction and less usage as a result of availability of resources, towering energy consumption, pollution of the environment by C02 emissions, lack of rehabilitation, ecosystem disturbance and generation of waste and neglectful disposal.
The sieve analysis and densities of C&DW obtained from returned readymix concrete aggregates for the purpose of this study indicated the material was well graded and dense, which indicated the material could easily be compacted on site. The plasticity index test indicated that the material was non-plastic, which indicated in turn that the material would not be susceptible to big volumetric changes as a result of changes in moisture content.
It was found that the optimum moisture content was on the higher side and the maximum dry density was on the lower side when compared to virgin aggregates usually used as base course material in South Africa. The high optimum moisture content was due to absorption of water by the cementitious paste from previous concrete. The lower maximum dry density was due to loss of aggregates stiffness since C&DW was subjected to secondary crushing. The California bearing ratio (CBR) for C&DW was on the lower side resulting in loss of aggregates stiffness due to secondary crushing; the results were also inconsistent as a result of different classes of concrete blended to obtain C&DW.
It was found that the UCS met COLTO requirements for C3 and C4 material and it increased as the cement content increased. Contrary to unconfined compressive strength (UCS), the indirect tensile strength (ITS) was less than that of C3 and C4 material. The ITS increased as the cement content was increased which was a positive indication that higher ITS could be achieved. The maximum dry density of stabilised C&DW increased as well and the increase may be attributed to addition of cement and cementitious properties from crushed concrete aggregates which also contributed in the hydration process.
Physical and chemical test results obtained in this study indicated that C&DW could be successfully recycled, which correlates with the literature review. European countries and Japan have successfully recycled C&DW; ISO 9000 was established in 1996 for C&DW. South Africa has to change its perception towards C&DW and develop a local standard to be used by the industry to promote the use of C&DW