Central University of Technology
Central University Of Technology Free State - LibraryCUT, South AfricaNot a member yet
2545 research outputs found
Sort by
The Role Of Higher Education Institutions In Fostering Innovation And Sustainable Entrepreneurship: A Case Of A University In South Africa
Get PDFArticleIn the new global economy, sustainable entrepreneurship has become a focal point of business as they seek to foster innovation and create sustainable products in the quest towards achieving sustainable development goals by the year 2030. The higher education sector plays a critical role as a catalyst in providing opportunities to nurture young and budding entrepreneurs and creating a platform where entrepreneurs can discover innovations and ideas that can be transformed into sustainable products. The study aimed to find out the role of institutions of higher education in promoting sustainable entrepreneurship, and to establish the characteristics necessary for sustainable entrepreneurs. Quantitative research methods were applied, with self-reporting questionnaires distributed to students at an institution of higher education in South Africa for data collection. Simple random sampling was adopted to select respondents (n=183). The results were analysed using means and exploratory factor analysis. Findings indicated that the institution is providing opportunities for nurturing sustainable entrepreneurship and innovation. Creativity was found to be the characteristic required for being a successful sustainable entrepreneur. The evidence from this study suggests that higher education institutions should be instrumental in creating opportunities and pathways as to how entrepreneurial characteristics can be enhanced to create sustainable businesses. Training should be offered on harnessing creativity and generating ideas that will help solve societal problems, while creating value
Disruption Of Microbial Cell Morphology By Buxus Macowanii
Get PDFArticleBackground: Microbial infections are one of the major causes of death globally. This is attributed to the rising
costs of primary healthcare and its inaccessibility especially in developing countries. Moreover, there has been an
increase in microbial strains that have reduced susceptibility to antimicrobial drugs. Research on the antimicrobial
properties of medicinal plants, which could address these problems, has become more important as they present
fewer side effects when compared to the antibiotics currently in use. This study evaluated the antimicrobial
properties of a methanolic extract from Buxus macowanii in order to assess its potential in the development of
novel antimicrobial drugs.
Methods: Antimicrobial activity of the extract was evaluated using the broth microdilution method. The effects of
B. macowanii on the morphology of B. cereus were observed using Scanning and Transmission electron microscopy.
Chemical profiling of the plant extract was performed using the GCMS.
Results: The extract showed antimicrobial activity against all the microbial species used. Microscopic examination
of the cells of B. cereus cells treated with Buxus macowanii showed some changes in morphology such as damage
of the cell wall, swelling of the cells and incomplete cell division that eventually resulted in cell death.
Neophytadiene, an antimicrobial compound was detected in the extract using GCMS.
Conclusion: The morphological disruptions of the cell wall of Bacillus cereus explain the antimicrobial properties of
B. macowanii and indicate its possible application in the development of natural antimicrobial drugs
Improving Energy Effciency of Thermal Processes in Healthcare Institutions: A Review on the Latest Sustainable Energy Management Strategies
Get PDFArticleHealthcare institutions consume large amounts of energy, ranking the second highest
energy-intensive buildings in the commercial sector. Within developed countries, the energy
consumption of healthcare institutions may account for up to 18% of the overall energy usage in
commercial sectors. Within developing countries, such as South Africa, the energy consumption
of healthcare institutions is observed to be a close second to the food service sector. Energy
consumption of healthcare institutions per bed typically range from 43–92 kWh per day. In this paper,
the largest energy consumers in South African healthcare institutions are identified and appropriate
energy-e ciency (EE) initiatives are proposed, in terms of performance, operation, equipment
and technology e ciency (POET). Two main thermal energy consumers are identified as heating,
ventilation and air conditioning (HVAC) and water-heating systems. These systems are critical
to patient health and may be classified as non-deferrable loads. Therefore, several initiatives are
suggested to improve the energy e ciency and demand-side management capability of these systems.
These initiatives are subdivided into di erent levels: the conceptual level, active level, technical
and further improvement level, as defined in the POET framework. At each level, energy-e ciency
initiatives are introduced based on potential energy savings and the e ort required to achieve these
savings. In addition, model predictive control (MPC) approaches are discussed and reviewed as part
of the further improvement section. Average possible energy savings ranged from 50%–70% at the
conceptual level, while energy savings of 15%–30% may be expected for energy-e ciency initiatives
at the active level. EE activities at the technical level and the further improvement level may result in
savings of 50%–70% and 5%–10%, respectively
Farmers’ Production Constraints, Perceptions and Preferences of Cowpeas in Buhera District, Zimbabwe
Get PDFArticleMany smallholder farmers face crop production constraints, especially under rapidly
changing climatic conditions. A survey was carried out to assess farmers’ production
constraints, traits, and preferred cowpea varieties. A semi-structured questionnaire was
used in a survey of Buhera District, Zimbabwe, in March and April of 2018. Women
farmers dominated the survey as they were 52% of the surveyed population, while men
occupied 48% of the total population. Eighty-three percent of farmers cited the shortage,
unavailability, and cost of fertiliser. Sixteen per cent of farmers acknowledged that they
do not have access to quality seeds, and 1% cited labour as the major constraint in cowpea
production. Cowpea yield varied from 100 to 500 kg/ha. However, 48% of farmers
harvested 200 kg/ha. As for abiotic factors, farmers ranked heat (86%), drought (10%),
and soil fertility (4%) as the most important abiotic factors. Ninety-one percent of
farmers ranked rust as the most destructive disease, while 2% ranked storage rot, 1%
ranked anthracnose, and 1% ranked downy mildew. Eighty-one percent of farmers cited
aphids as the main pests, while 3% ranked thrips, 3% ranked legume borers, and 2%
ranked pod borers as other pests. Fifty-two percent of farmers preferred varieties that are
resistant to diseases such as rust, whereas 48% were not concerned about diseases. As
for qualitative traits, 50% of farmers had no specific colour preference, 32% preferred
white colour, 14% preferred brown colour, 3% preferred red colour, and 1% preferred
tan colour. For quantitative traits, such as grain size, pod size, plant height, and head size,
the preferences of farmers varied. Ninety-nine percent of the farmers interviewed
preferred cowpea varieties that are bred for drought tolerance, as Buhera District is
frequented by intermittent droughts. Farmers’ experience in growing cowpeas ranged
from 5 to 30 years. The top ranked accessions were CBC1, IT 18, and Chibundi
Chitsvuku, while the least ranked was Kangorongondo. Identified constraints to cowpea
farming included lack of education, insect pests, diseases, drought, weeds, harvesting
difficulties and a lack of agriculture extension advice. The survey showed that there is a
need to breed for biotic factors such as pests and diseases and abiotic factors such as
drought and moisture stress
Development Of An Auricular Prosthesis Positioning Guide Using Additive Manufacturing Technologies
Get PDFDissertationFacial deformities associated with congenital disorders or loss of facial features due to trauma or disease can have a devastating effect on the social well-being of a patient. This study focuses on deformed or missing auricles (ears) and their replacement with silicone prostheses. These prostheses are retained by craniofacial implants which are implanted into the temporal bone area of the skull in the appropriate position of the auricle. Surgeons find it difficult to place the implants accurately in relation to the missing auricle. The patient lies on their side on the operating table during the procedure and is largely covered by drapes to create a sterile working area. This makes it difficult to reference the position of the prosthesis, since the face and opposite auricle are covered.
The aim of this study was to develop patient-specific devices using additive manufacturing technologies and associated software to indicate the positions of craniofacial implants which retain the auricular prostheses and to correctly orientate the prostheses relative to the positions of the implants. The geometry of the patient is determined using Computed-Tomography (CT) scanning and the opposite auricle is mirrored in the virtual environment through specialized software from Materialise. An iterative design process was followed to develop a positioning guide for placing the implants, with each design iteration improving on the previous one. In addition to the positioning guide, an orientation guide was developed that orientates the prosthesis accurately in relation to the implants. This is a new development in the field of maxillofacial prosthetics and has not been attempted before. The positioning/orientation guides are produced in nylon through the laser sinter additive manufacturing process. Craniofacial implants were developed and placed for patients in three case studies. The accuracy of placements was determined by CT scanning the area with the implants and overlaying the images onto the originally planned positions. Results showed relatively accurate positioning of the implants using the positioning guides, while reducing risk by not having to drill without reference points. The cost of the procedure is also reduced by shortening operating theatre time
The Perceived Impact Of Integrated Development Planning (Idp) On The Social And Economic Development Of Local Communities Of Magareng Local Municipality, Northern Cape Province
Get PDFDissertationThe first democratic elections in 1994 has resulted in the government beginning a fundamental transformation process in all three spheres of government to give effect to the Constitution of the Republic of South Africa, 1996, and to address numerous developmental challenges that local government faced. The municipalities are responsible for the provision of services to the communities in a sustainable and accountable manner, as well as to promote the social and economic development of their communities. Therefore, a municipality must structure and manage its administration as well as its planning and budgetary processes to give priority to the basic needs of the community, to promote the social and economic development of the community, as well as to participate in national and provincial development programmes.
The main purpose of an Integrated Development Plan (IDP) of a municipality is to enhance the level of service delivery, to promote sustainability and to address poverty through an integrated and aligned approach among role players and stakeholders within the municipalities’ jurisdiction.
The main purpose of this study was to analyse the perceived impact of the IDP on the social and economic development circumstances of the communities within the Magareng Local Municipality of the Northern Cape Province. For the realisation of the aim and the objectives of this study a qualitative research methodology was adopted. The literature study was based on the requirements of a qualitative study, which includes extensive literature, legislation, policy documents journal articles, books, conference papers, internet and government reports about, developmental local government, IDP and LED in the context of South African local government.
An empirical study was also administered. A semi-structured questionnaire was utilized to elicit information from selected ward councilors of the Magareng Local Municipality regarding the perceived impact of IDP on the social and economic development of communities of Magareng Local Municipality of Northern Cape Province. Except for the above, a semi-structured interview schedule was used to conduct semi-structured interviews with selected municipal officials responsible for IDP and LED of Magareng Local Municipality.
It was found during the literature review that although the IDP is an important strategic tool to address the socio-economic backlogs and development challenges of municipalities, more still needs to be done in order to ensure that the medium-term and long-term priorities are effectively implemented to promote effective service delivery and socio-economic conditions of communities in the Magareng Local Municipality. From the findings of the semi-structured questionnaire it was found that the majority of the ward committee members were of the opinion that the social development needs of the local communities of Magareng Local Municipality were not adequately addressed by the municipality. From the findings of the semi-structured interviews the majority of the municipal officials were of the opinion that the municipality was unsuccessful in its role to promote developmental local government with the aim to improve the social and economic circumstances of local communities.
It was recommended that the Magareng Local Municipality should focus more on ward-based social and economic developmental needs and priorities in its IDP, such as poverty alleviation, job creation, youth development and local economic growth related LED projects and programmes. This could be done by attracting investments from business partners and other stakeholders. The vigorous implementation and execution of IDP and LED related projects and programmes need to be at the forefront of all social and economic development initiatives. It is recommended that the provincial government and sector departments provide support, guidance and sufficient funds to ensure that Magareng Local Municipality will be able to implement its IDP and LED related projects and programmes effectively. This will assist the municipality to complete and reduce the turnaround time of IDP and LED related projects and programmes to promote the social and economic development of local communities
Bioaerosol Composition And Associated Hazards In A Prominent Fruit Beverage Production Facility
Get PDFThesisBioaerosols are defined as aerosols that comprise particles of biological origin or activity that may affect living organisms through infectivity, allergenicity, toxicity, or through pharmacological or other processes. Interest in bioaerosol exposure has increased over the last few decades. This is mainly due to the association of bioaerosols with a wide variety of adverse health effects that have a major public health impact such as contagious infectious diseases, acute toxic effects, allergies, and cancer. Exposure to bioaerosols may cause three major problems in the food industry, namely: (i) contamination of food (spoilage); (ii) allergic reactions in individual consumers; or (iii) infection by means of pathogenic microorganisms present in the aerosol. Unfortunately, there is limited information available with regards to the specific organisms/biological agents involved in these processes and how exactly these processes occur. This deficiency in knowledge can be attributed to a lack of research on these processes, possibly because the importance of bioaerosols has not been considered. Furthermore, international standards on acceptable maximum bioaerosol loads are not uniform, which creates confusion as to what the acceptable limit of microorganisms in bioaerosols should be. There is also a lack of standardised methods for the collection and analysis of bacterial and fungal bioaerosols, making it difficult to compare the data released by various researchers.
According to the literature, controversy exists regarding: (i) the effect of the environment and season on bioaerosols; (ii) types of sampling procedures; (iii) whether the detection of the culturable fraction of bioaerosols is efficient; and (iv) whether these bioaerosols can in actual fact affect the product or cause occupational health problems. The aim of this study was therefore to address the above-mentioned questions by means of an investigation in a selected fruit juice production facility. The culturable and non-culturable fraction of bioaerosols were collected in this facility by active sampling using SAMPL’AIR LITE (AES Chemunex), a standard bioaerosol sampler, in different areas of the facility during the peak and off-peak seasons.
It is noteworthy that the microbial counts observed during this study were high, with high total microbial counts detected during both sampling periods. This indicates that the air in the selected facility created ideal conditions for all types of bioaerosols. Traces of presumptive positive pathogens as well as yeast and mould were observed in the samples collected from five designated areas. Several environmental factors were analysed, but temperature was the only concrete environmental factor observed in the facility during this study. However, statistical analyses indicated that temperature had no statistically significant effect on the presence of bioaerosols in the facility. More than 380 bioaerosols were detected during culturable identification, with 92 different species confirmed. A unique group of controversial bioaerosols was identified, ranging from highly probable pathogens such as Bacillus spp., Staphylococcus spp. and even Candida spp. Not only were harmful microorganisms identified in the bioaerosols, but microorganisms that are capable of bio-diesel production, that possess anti-tumour activities and that are capable of post-harvest control were also detected. Data obtained by PCR-DGGE analysis were used to determine the similarity, richness and diversity of the bacterial composition in the different areas of the facility during the two sampling seasons. The highest microbial diversity and richness was obtained in the air of the area where the bottles were filled with the final product and where a large number of personnel was present.
Data obtained during this study indicated high microbial counts and species diversity in the air of this specific production facility. Even though this does raise concern, it is important to note that the dose-relationship of microorganisms, even for pathogenic agents, has not yet been established. This is mainly due to a lack of valid methods to qualitatively assess exposure. It is therefore clear that there is still a need for the development of an environment/sample/facility sampler for bioaerosols in order to facilitate the immediate evaluation of the specific health risks associated with a specific industry. The information obtained by means of this study will be useful to address this gap in knowledge and will aid the fruit juice industry to better understand and control bioaerosols in their facilities. This may also relate to other industries where it is necessary for more specific, valid risk assessments and control of bioaerosols in order to ensure product and occupational health safety
Metal Additive Manufacturing Of Titanium Aluminides From Blended Elemental Powder
Get PDFDissertationTitanium aluminide is considered a key material for high performance gas turbines for aircraft engines, manufacturing of engine valves and a variety of automotive applications. This is due to the attractive high oxidation resistance and strength retention of the Titanium aluminide alloy at high temperatures.
The limitations of the conventional methods of manufacturing Titanium aluminide alloy components with precise geometry and near net shape functional characteristics have limited the usefulness of the Titanium aluminide alloys. However, additive manufacturing (AM) methods such as direct metal laser sintering (DMLS) have proven to have the capacity to uncover the full potential of the Titanium aluminide alloy by producing components with complex shapes.
The aim of this study was to determine the feasibility of using a blend of elemental Ti and Al powders in a DMLS system, to make parts that have comparable or better geometric, functional and microstructural properties to that of the conventionally processed titanium.
In this, study Ti6Al and Ti46Al alloys were investigated, using blends of elemental powders of Ti and Al. Single tracks were manufactured and single layers were built using a wide range of process parameters to determine the optimum process parameters for use in building good Titanium aluminade parts. Finally, two three-dimensional (3D) samples were built from Ti6Al (low Al content) and Ti46Al (high Al content).
The Ti6Al sample was built at the optimum parameters of laser power 150W and scanning speed 1.2m/s and the Ti46Al sample was built at the optimum parameters of 170W laser power and 0.1m/s scanning speed as identified in this study.
The Ti46Al 3D sample was not a success and further analysis could not be completed as the 3D sample collapsed.
The Ti6Al sample was a success, showing good overlapping of the single layers forming the 3D part. Good penetration depth of the single layers was achieved, complete melting and homogeneity of the powder were achieved, and finally, a good dense 3D part with α+β microstructure was achieved. A 2% loss of Al in the produced 3D part of Titanium aluminide alloy, which was attributed to the differences in thermo-physical properties between the powders (Ti and Al).
The process of rescanning improved the homogeneity and promoted complete melting of the powder. Improving the mixing method of the powders prior to in-situ alloying improved the homogeneity of the alloy by reducing Al rich zones in the Ti matrix. A 2% Al loss allowance should be considered in further studies to ensure that the resultant alloy would meet the required compositional specification
Stress Intensity Failure Rate Propagators Of Flexible Pavement
Get PDFThesisA responsive pavement management infrastructure is essential for providing durable pavement infrastructure. This need has been accentuated by the quest for sustainability through the adoption of Road Traffic Management System (RTMS) patterns as employed by the various Departments of Transportation (DOT) in South Africa. It can be summarised that increasing humidity/moisture content resulting in percentage increase in saturation content of the underlying base, subbase or subgrade layers will significantly result to a reduction of the Resilient Modulus (MR) of the entire pavement structure weather flexible or rigid. However, this scenario poses a great threat to the structural carrying capacity of the pavement structure. Therefore, it is imperative to provide a solution to such critical problems as they occur and when there is no control to avert them. This can, only be made possible by identifying the exact cause of the problem and providing a feasibly efficient and achievable solution. In the design of roads, flexible pavement has overtime experienced associated distress failure modes resulting in potholes, loss of skid resistance, and reduction in riding quality, noise and road surface ponding. Many of these have being tackled by research, both in the past and currently. The structural collapse of pavement is as a result of distress modes caused by human factors, construction error, excessive traffic loading, environmental factors, cumulative design and geometric errors results to unnecessary loss of strength and stability during the estimated design pavement service life. The objective of this current study is to develop stress intensity failure rate propagators induced by the factors of distress earlier mentioned in order to develop performance functions of asphaltic pavement model using the finite element method followed by a semantic stream-web data analysis (JAVA Expert System Shell analysis JESS). Multivariable transfer functions are generated in order to assess the different modes of failure for Mode I where the onset of crack begins to develop. Moisture sensors are embedded into the pavement in other to determine the real time failure modes populated under service loading and environmental conditions. Damage models are obtained to evaluate the evolution of crack growth and the strain energy release rate for failure mode I (crack initiation). The analysis of this study is further modelled in Abaqus CAE 6.13 as well as a proposed web-based computation analysis of pavement failure (JESS). The FE model indicates that at 20% moisture ingress, the vertical deformation of the subgrade is stable with a value 6.65 E-05. With further increase in moisture, the pavement stiffness reduces and the deformation increases with a failure rate value of 9.68 E-05. The difference indicates that there is a high percentage correlation between moisture content or saturation content increase in pavement and the resilient modulus of the pavement (Stiffness coefficient). Further subjecting the pavement to the same load or increasing load cycles will result in gradual delamination and further yield to total deformation. The results are as presented and discussed as the data obtained from the sensor probes are discretised for analysis in the workbench. A network level pavement management system to contribute to the development of a framework for evaluating pavements’ quality index (PQI) and service life capacity with varying environmental and climatic conditions is presented. The results indicate variation of stiffness with increasing moisture content. Increase in moisture propagation increased saturation of the unbound granular base which reduced the elastic modulus of the subbase layer and reduced the strength of the pavement leading to formation of bottom-up cracks and cracking failure. The horizontal tensile strain (E11) at the asphalt layer at 20% was 69.57x10-4, which increased to 140.8x10-4 at 60% moisture content. The horizontal deformation (E22) reduced, assuming that the material is experiencing work-hardening and no further stress can result to any significant damage. The damage remained at a constant value of 96.8 x 10-4 at 60% saturation. Consequently, the performance of the pavement is affected by temperature gradient. This implies that increasing temperature gradient results in reduction in stiffness of the asphalt layer. In tropical regions, this can result to immediate rutting failure of the asphalt layer, which overtime leads to formation of top-down cracks and potholes with increasing moisture content, even if it is a newly constructed road less than two years old. The web data architecture analysis provides deflection values for failure occurring within the pavement underlying layers. The findings indicate that there is a high correlation between Environmental Condition and road pavement (Asphalt Concrete). The result indicates that increasing temperature gradient of the pavement reduces the fracture energy of the pavement, which results in delamination and collapse over a longer period of time. On the contrary, reduced temperature gradient increases the fracture Energy, making the pavement stiffness high and resistant to failure, but at very low temperatures a compromise is reached and the strength is breached resulting in a brittle material (glass). Although the failure is not visible at the onset of crack propagation, but continual exposure to increasing temperatures as well as increasing moisture content will lead to failure of the pavement before the design life is reached. There is also a surge in the relationship between Pavement Fracture Energy and the Pavement Resilient Modulus. Further, it is found that, the higher the temperature, the higher the rate of deflection and the lower the temperature, the lower the deflection
Developing An Artificial Algorithm To Predict Energy Consumption In A Traditional House Adapting To External Environmental Conditions And Occupation
Get PDFThesisThe aim of the research was to development a prediction model that could control electricity consumption in a traditional house, adapting to external environmental conditions and occupation. As identified high-end users of electricity, a backup geyser element in a solar geyser solution, including a swimming pool pump, was identified to be controlled more efficient than a time-based controller, as an end result with the same or higher customer satisfaction index to the occupant.
A system was developed, recording multiple remote sensor readings from Internet of Things (IoT) devices to a central SQL database which included the hot water usage and heating patterns. Official weather predictions replaced physical sensors, recording environmental conditions.
Fuzzifying the sensor recordings into four linguistic terms simplified hot water usage. Partitioning clustering was used to determine relationship patterns between weather predictions and solar heating efficiency. A Hidden Markov Model was used to profile the system, with the Viterbi algorithm calculating the geyser and pool solar heating predictions, while the Baum-Welch algorithm trained the system.
The solar geyser’s standby element was controlled by a time-based controller heating water to pre-set value if required. During this investigation the time-based controller was simulated with a controller profiling weather conditions and hot water usage. Adjusting pre-set temperatures accordingly without human intervention. The same algorithm was used to simulate a timer controlling a swimming pool pump, but excluding the hot water usage. Simulations found that profile base prediction controller can increase user satisfactions, including a maximum of twenty percent electrical power savings against time-based controllers