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The evaluation of the Standing Committee on Public Accounts' oversight role and purpose in promoting accountability :a case of the Limpopo Provincial Legislature
Get PDFThesis (Ph.D. (Administration)) -- University of Limpopo, 2023This study explored the underlying problem of financial mismanagement in the public
sector with pertinence to public accountability in South Africa. The problem of accountability has manifested in growing wasteful, irregular, and fruitless expenditure
in the post-apartheid era, which is confronted by other multitude of social-economic
challenges. Post-1994, South Africa embarked on an effort of policy development
and legislative reforms to cater to public service regulation. These include legislative
frameworks such as the 1999 Public Finance Management Act and the 2003 Municipal Finance Management Act. To date, South Africa is still struggling with measures to counter corruption and the abuse of state resources. Given that South Africa has instituted and inaugurated several critical institutional mechanisms for legislative oversight, the study sought to explore the rationale for rampant problems pertaining to non-compliance,
unaccountability, and lack of answerability within South Africa’s public sector. This
calls for research since these problems have serious implications for the future of the
country and its ability to address inequalities relating to the history of exclusion of
most people, especially Africans. Due to a rise in irregular and wasteful expenditure,
this study highlighted the roles and functions of SCOPA as a key parliamentary tool
for advancing accountability. The research objectives for the study were grounded
on the growing problem of financial misconduct and abuse of public funds in the
public sector due to lack of accountability, despite the existence of SCOPA as a
parliamentary oversight mechanism. From the reviewed literature, the Limpopo Provincial Legislature faces several challenges such as a lack of accountability, specifically on executives’ accountability on their actions. Also, several departments attest to having several irregularities, fruitless and wasteful expenditures that affect service delivery, otherwise, the need for SCOPA to intervene. However, the SCOPA resolutions are not effectively implemented by the Limpopo Provincial Department and its municipalities. It is on this basis that the current study sought to evaluate SCOPA’s oversight role and
purpose in promoting accountability in the Limpopo Provincial Legislature.
The study adopted theory triangulation as the theoretical approach for the study, this
is evident through the utilisation of four theories, which includes, Principle-agent
theory (Mithick;1970); Functionalism theory (Parsons, 1930s); Constitutionalism
theory (Locke;1680s) and Institutionalism theory (Meyer & Rowan, 1970s). These
theories were adopted as the theoretical points of departure for the study due to their
richness in examining issues of oversight and accountability. To explore the study, a
triangulation research approach (qualitative & quantitative) was adopted. The data
was collected from SCOPA members and members of the Limpopo Provincial
Legislature. The collected data was analysed quantitatively and qualitatively for
detailed findings. The study reveals that SCOPA is not operating effectively to oversee and monitor public expenditure. The oversights done by Limpopo Provincial Legislature did not address issues pertaining to public finance management, which speaks volume in
terms of accountability. From the findings of the study, it is evident that Limpopo
Provincial Legislature is still facing several challenges, which ultimately affect service
delivery. Towards addressing the problem of oversight and accountability, most of
the study’s respondents recommend that the system, process, procedures, and
policies be reviewed, and SCOPA is required to establish new strategies that will
help to fast-track the investigation within public institutions. Also, the provincial
department is required to provide reviewed information within the agreed period. This
study submits that provincial legislature should establishes other independent
institutions to work in collaboration with SCOPA
Evaluation of exotic sorghum germplasm lines for yield and adaptation in the Semi-Arid Region of Limpopo Province (Mankweng), South Africa
Get PDFThesis (M. Agricultural Management (Plant Production)) -- University of Limpopo, 2023Sorghum (Sorghum bicolor (L.) is a grass that is grown for its grain, and is an essential crop, which can be used as a staple food for humans and livestock. It can adapt to drought, salinity, and high temperatures which makes it best suited for future climate change. Sub-Saharan Africa (SSA) is facing a challenge of food insecurity and drought, and sorghum is one of the cereal crops in SSA’s food value chain, and effective production, especially by smallholder farmers, will reduce these problems. Sorghum is regarded as a stable crop across the African continent and it is rich in nutrients. 13 exotic sorghum germplasm for evaluation for adaptation and yield in South Africa were introduced to reduce food insecurity with nutritious sorghum. The experiment was conducted at the University of Limpopo farm (Syferkuil), and was laid down in an incomplete block design with three replications and 17 varieties of exotic sorghum germplasm, which were planted in two seasons, 2021 and 2022, to check the adaptation, yield, and nutrient content of the varieties and these were compared with the check line from South Africa (Pan 606). The results show that some of these varieties performed better than the check line. There was a significant difference (P<0.05) obtained among varieties in both 2021 and 2022 for 200 seed weight, and the test lines (Fara Kano, ICSG1780727) performed better than the check line in both seasons. Again, there was a significant difference (P<0.05) obtained among the varieties in calcium and sodium. ICSG 1780724 and Yarlabe performed above the control in the concentration of sodium while the performance of all the test lines was above the check line on the concentration of calcium. The varieties, which performed better than the check line, can be used by breeders to improve the different traits and be released for smallholder farmers’ cultivationSAB and AgriSet
Conundrum and nightmare in the politics of the laws regulating arbitration as opposed to mediation in the workplace in South Africa
Get PDFThesis (LLM. (Labour Law)) -- University of Limpopo, 2023The South Africa labour law, particularly the Labour Relations Act, 66 of
1995 (LRA) provides for alternative labour dispute resolution that is quick,
cost effective and accessible. By doing so, the LRA provides for
establishment of the Commission for Conciliation, Mediation and
Arbitration (CCMA) to serve as alternative dispute resolution body. Despite
the benefits (quick, cost effective and accessible) of the CCMA, there are
rising concerns about the impartial and biased conduct of the CCMA
commissioners during arbitration. Consequently, this study critique the
laws regulating arbitration as opposed to mediation in the workplace in
South Africa. CCMA commissioners preside over labour disputes and
make impartial decisions based on the facts and evidence presented to
them. The LRA and CCMA Code of Practice require CCMA
commissioners to be unbiased, fair, and objective when making decisions.
There are however in contrary rising concerns that the CCMA
commissioners are biased and partial during arbitration proceedings. The
study found that the CCMA Code and LRA do not provide adequate
provisions to ensure that CCMA Commissioners are always unbiased and
impartial during arbitration. This was substantiated through comparative
analysis between Canada and South African alternative dispute resolution
laws. In South Africa, parties to arbitration often do not personally choose
a CCMA commissioner to preside over their matter as that decision is
often made by CCMA officials. In contrary, the Canada extensively
encourage parties to mutually choose personally an officer to preside over
their matter. This then makes the arbitration in Canada to be often
impartial and unbiased in Canada as compared to South Africa. The study
recommended that the South African law can learn from Canada to
enhance the extent of unbiased and impartiality during CCMA arbitration
An assessment of domestic greywater reuse : a case study of Ga-Thoka Village in Polokwane Local Municipality, South Africa
Get PDFThesis (M. Sc. (Geography)) -- University of Limpopo, 2023South Africa is a water scarce country, the 30th driest in the world. Certain parts of the
country have been experiencing severe droughts since 2015. The study titled: An
assessment of domestic greywater reuse: A case study of Ga-Thoka village in
Polokwane Local Municipality, South Africa, aimed to assess domestic greywater reuse
in Ga-Thoka village. Objectives of the study were to identify sources of freshwater and
the nature of potable water supply, analyse the quality of greywater from selected
households, establish the potential of greywater reuse by the households, and to
determine the awareness and perceptions of the households on reuse of greywater.
Data collection methods used to collect primary data included questionnaires, field
observations and the key informant interview. Secondary data was also collected for the
study. Greywater samples were collected from selected households in the village. The
collected greywater samples (93) were taken to CDM water laboratories for the analysis
of greywater quality. The analysis revealed the presence of metals such as copper and
sulphates. The study found that 85% of the respondents said they always have
freshwater available and it was discovered that 51% of the respondents get freshwater
from their home taps. Ninety-two percent (92%) of the households generate greywater.
Sixty-eight percent (68%) of the respondents do not have knowledge about greywater
importance. The Pearson Chi Square test revealed association between factors
investigated (socio-economic characteristics, water scarcity and awareness) and the
willingness to reuse greywater by the respondents. It was concluded that Ga-Thoka
village households reuse their greywater mostly for irrigation. The study recommends
that the households should reuse their greywater on other different activities that do not
strictly require freshwater
Detecting and mitigating the distributed denial of service attacks in software defined networks using machine learning approach - the integrated random forest and K-nearest neighbours classifiers
Get PDFThesis (M.Sc.(Computer Science) -- University of Limpopo, 2023Distributed Denial of Service (DDoS) attacks present substantial risks to network availability and stability, especially within the realm of Software Defined Networks (SDNs). Inventive and efficient detection and mitigation methods become imperative to counter the continuously evolving nature of these attacks.
SDN is characterized by its dynamic and programmable nature and is susceptible to DDoS attacks that can disrupt network operations. Traditional methods for detecting and mitigating DDoS attacks in SDNs may not be sufficient due to the evolving nature of these attacks. The research aims to develop a more effective and adaptive solution by using the Random Forest (RF) and k-Nearest Neighbours (KNN) machine learning algorithms. This approach seeks to enhance the accuracy, speed, and resilience of DDoS detection and mitigation in SDN networks.
The research aims to address the pressing need for robust DDoS detection and mitigation mechanisms in SDNs by harnessing the power of machine learning, through the integration of RF and KNN and improving the KNN model. This approach is motivated by the evolving threat landscape, the unique challenges posed by SDN environments, and the potential for advanced machine learning techniques to enhance network security.
Furthermore, the research objective is to enhance the K-Nearest Neighbors (KNN) classification algorithm. By looking deep into KNN and addressing its limitations, this study seeks to refine and optimize the algorithm's performance for various real-world applications. Through a systematic exploration of parameter tuning, feature engineering, and innovative techniques, this research aims to provide a more accurate and efficient KNN classifier.
This study investigates the utilization of a machine learning approach, specifically Random Forest and K-Nearest Neighbours classifiers, to identify and counteract Distributed Denial of Service (DDoS) attacks in Software Defined Networks (SDNs). The research commences by exploring the fundamental concepts of SDNs and DDoS attacks, highlighting their interplay and the unique challenges they pose to network availability and stability. The methodology for the study typically involves steps such as Data Collection (gathering network traffic data from SDN, including both normal and potentially malicious traffic.), Data Preprocessing (Clean and preprocess the collected data to remove noise, handle missing values, and normalize features), Feature Engineering: Identify relevant features or attributes in the network traffic data that can help distinguish between normal and DDoS attack traffic. By following the methodology presented in this study, we can systematically investigate the feasibility and efficacy of the proposed approach for detecting and mitigating DDoS attacks in SDN.
A comprehensive review of existing literature is conducted to understand the state-of- the-art techniques employed for DDoS detection and mitigation, with an emphasis on machine learning approaches. Expanding on the current understanding of mitigation against attacks, this thesis suggests employing Random Forest and K-Nearest Neighbours classifiers to improve the precision and effectiveness of DDoS detection in SDN environments. The proposed framework utilizes the ensemble learning abilities of Random Forest to address the challenges posed by the complex and diverse network traffic features, while the K-Nearest Neighbours algorithm offers the necessary flexibility and prompt decision-making for timely mitigation.
To evaluate the proposed model, extensive experiments are conducted using a realistic SDN simulator and diverse DDoS attack scenarios. Multiple performance metrics, including accuracy of detection, rate of false positives, and response time, are assessed and compared to alternative methods. The results demonstrate the superiority of the Random Forest and K-Nearest Neighbours classifiers in detecting and mitigating DDoS attacks effectively, efficiently, and with minimal impact on legitimate traffic.
In conclusion, this study shows that the improved KNN algorithm with a n_neighbours value of 2 has a higher accuracy rate compared to the Decision Tree classifier.
Furthermore, this research explores the challenges and limitations associated with the proposed model and provides insights for further improvements. This dissertation makes a valuable contribution to the domain of network security by introducing a novel methodology that employs machine learning techniques to identify and counteract DDoS attacks in SDNs. The model presented not only enhances the precision of attack detection but also diminishes response time, empowering network administrators to
safeguard their SDN infrastructure against intricate and evolving DDoS attacks effectively
Effects of biofertilizers on grain yield and biological nitrogen fixation of tepary bean
Get PDFThesis (M. Agricultural Management (Plant Production)) -- University of Limpopo, 2023Tepary bean, a drought-tolerant bean, has become popular among poor small-scale
farmers in semi-arid countries. Field experiments were conducted on the effect of
biofertilizers (Bradyrhizobium japonicum (B. japanicum) inoculation, versicular
arbuscular mycorrhizae, and seaweed extract) on grain yield and biological nitrogen
fixation of tepary bean in two different locations, namely Syferkuil and Ga-Molepo farm.
One-way, two-way, and three-way analysis of variance (ANOVA) were used to compare
bradyrhizobium inoculation, versicular arbuscular mycorrhizae (VAM), and seaweed
extract application performance on plant growth and yield parameters (50% emergence,
50% flowering, plant height, chlorophyll content, number of branches per plant, number
of pods per plant, pod length, 90% maturity, number of seeds per pod, 100 seed weight,
pod weight and grain yield). Amongst these plant growth and yield parameters, a
significant difference was observed in emergence, plant height, chlorophyll content,
number of branches per plant, number of pods, pod length and number of seeds per
plant in response to location, VAM, and seaweed extract. The location had significant
differences in 50% emergence, plant height, chlorophyll content, number of branches
per plant and number of pods per plant. VAM showed a significant difference in plant
height, chlorophyll content, pod length and the number of seeds per pod. Seaweed
extract had a significant effect on plant height and pod length. The interaction effect of
VAM and seaweed extract levels at Syferkuil showed no significant impact on the
chlorophyll content of tepary beans. A significant difference was observed in chlorophyll
content in response to the interaction effect of VAM, seaweed extracts and location. The
interaction of location, VAM and seaweed extract on chlorophyll content also observed
a significant difference. This study also determined the treatment effect on the tepary bean's biological nitrogen
fixation (BNF). The 15N natural abundance approach was used to evaluate nitrogen
fixation. Shoot dry matter, %Ndfa and N-fixed of tepary bean grown at Ga-Molepo
increased significantly than at Syferkuil. Versicular arbuscular mycorrhizae,
bradyrhizobium inoculation and seaweed extract had no significant difference in dry
matter, %Ndfa and N-fixed. However, the results showed that treatments influenced
these parameters. VAM (inoculated), seaweed extract (application) and bradyrhizobium
(un-inoculated) fixed the most N at Ga-Molepo (164.96; 183. 81 and 180. 25 kg/ha,
respectively) and therefore showed more significant dry matter accumulation. At
Syferkuil, VAM (un-inoculated), bradyrhizobium (inoculated) and seaweed (no
application) contributed the most symbiotic N (56. 1; 43. 48 and 42.97 kg/ha,
respectively).
Tepary beans planted at Ga-Molepo significantly obtained greater mean dry matter (32.
70) than Syferkuil (16. 47). Tepary beans grown at Ga-Molepo significantly received a
greater mean %Ndfa (27. 19) at Syferkuil (12. 57). The percent N derived from fixation
was 35% at Syferkuil and 22% at Ga-Molepo. These outcomes confirmed the view of
this study that production and biological nitrogen fixation of tepary beans (and other
grain legumes) can be enhanced using biofertilizer
Detection cerebrovascular disease in brain images using convolutional neural network
Get PDFThesis (M.Sc. (Computer Science)) -- University of Limpopo, 2023Cerebrovascular disease is the world's second major cause of mortality and disability, and the fourth major cause of mortality and disability in South Africa. Cerebrovascular disease occurs due to issues of the brain's blood supply, either the blood supply is cut off or a blood artery within the brain bursts. Radiologists have the responsibility to detect cerebrovascular disease. We now have technology which can help them to better detect this disease. Medical imaging plays an important role in detecting diseases. This study presents implementation of a detection system using artificial intelligence model, namely, convolutional neural networks to help in detecting cerebrovascular disease from magnetic resonance imaging (MRI) scans. Brain images using MRI was obtained from kaggle pub-lic dataset. Segmentation process was applied in this study to normalise images since the images came in different sizes. The effectiveness of the concept was demonstrated using a confusion matrix. The accuracy rate was plotted using the Receiver Operating Characteristics (ROC) curve. The evaluation results show that the Convolutional Neural Network (CNN) model detect cerebrovascular disease successfully with validation accu-racy rate of 90% and test accuracy rate of 80%. The training procedure could be improved by using a larger MRI dataset.IBM
ETDP SIT
Using Van Hieles's geomentric model to improve grade 11 learners reasoning when solving circle riders
Get PDFThesis (M.Ed. (Mathematics Education)) -- University of Limpopo, 2023In this study, I am reporting on the use of Van Hiele’s model to improve Grade 11 learners’ reasoning when solving circle riders. Studies have shown that geometry concept is deemed challenging for many learners in the country and abroad, as a result this study adopted Van Hiele’s model to improve the learners’ challenges when solving circle riders. A qualitative research approach was found suitable for this study because the findings of this study were reported using learners responses to given tasks. The learners’ responses gave an in-depth understanding of their challenges which cannot be generalised like with statistical data. A case study research design was used, following Merriam’s perspective; this was adopted because the study reports on findings from different sources of data. A sample for this study comprised a group of 34 Grade 11 learners from a technical school, in Sekhukhune District in Limpopo Province, South Africa. Data were collected using a pre-intervention activity, participant observations, and a post-intervention activity. Participants were given a pre-intervention activity to establish the level at which they operated before intervention. They were also given activities to complete during intervention lessons while I observed what transpired and how they reasoned when responding to the given activities. Later they were given a post-intervention activity, which was used to check if there was an improvement in their reasoning. The data were analysed using content analysis in three phases. This was done by scrutinising learners’ responses to pre-intervention activity, participants’ observations and post-intervention activities.
Findings have shown that the use of Van Hiele’s model significantly enhanced the performances of learners when solving circle riders. The findings also revealed significant changes in learners’ reasoning, with the majority of learners’ post-intervention operating at a higher level of Van Hiele’s Model as compared to prior intervention. This shows that the use of Van Hiele’s model in teaching plays an important role in geometry learning and allows learners a chance to think critically, which helps in their conceptualisation of the knowledge area and improves their reasoning. From the findings it is recommended that there is a need for more studies that use Van Hiele’s model in all the grades and using large population of learners or more than one school for attainment of results that can be easily generalise Additionally, implementation of Van Hiele’s model within all mathematics content knowledge areas in which learners can be taught from lower level (−1) before they can be introduced to questions at higher level (). Furthermore, I recommended a need for studies that focus on how Van Hiele’s model can be used in improving teachers’ pedagogical content knowledge when teaching Euclidean geometry in all the grades. I am also of the view that there is a need for geometry content in Mathematics textbooks to be aligned and written in a way that allows learners to progress through different levels of Van Hiele’s Model. Lastly there must be more research focusing on vocabulary that learners encounter when giving reasons when dealing with the concept of geometry
Reducion of a, B-alkynyl carbonyl compounds using SnCl2 and computational investigationof the reaction mechanism.
Get PDFThesis (M. Sc. (Chemistry)) -- University of Limpopo, 2023The development of an efficient method for the reduction of α, β-alkynyl carbonyl compounds, is mostly important in organic synthesis, playing a crucial role in the synthesis of pharmaceuticals, pesticides, polymers, and other valuable chemicals. From the literature, no reaction was reported when tin (II) chloride (SnCl2) was used for the reduction of alkyne to alkane. The aim of this research was to investigate the reduction of conjugated α, β-alkynyl carbonyl compounds into alkanes using commercially available SnCl2 and other metal salts known to reduce the nitro group, such as iron (Fe) and zinc (Zn). Our approach to the synthesis of 1-(6-nitroquinoxaline2-yl)hex-1-yn-3-one 17, involves the use of 6-nitroquinoxalin-2-yl-benzenesulfonate 34 as a substrate for Sonogashira cross coupling with terminal alkyne to give appreciable yield of 1-(6-nitroquinoxalin-2-yl)hex-1-yn-3-ol 35, followed by oxidizing using PCC or Jones reagent to give 1-(6-nitroquinoxalin-2-yl)hex-1-yn-3-one 17. The oxidised product was used to optimise the reduction reaction at different temperatures (˚C), time (hours), and equivalences of SnCl2. Our first desired product 19 was obtained with yields ranging from 18 - 47%, with alkyne and nitro reduced to alkane and amine respectively when using 5 equivalents of SnCl2. During the optimisation, compound 17 also produced compound 36 with yields ranging from 45-80% with only reduced alkyne to alkane and nitro remaining unchanged, when number of equivalences of SnCl2 were reduced to 2 eq. We then introduced the oxidised compound 42 since it contains chloride instead of the nitro and we manage to reduce the alkyne to afford compound 43 with yields ranging from 55-73%. The optimised conditions were extended to other α, β-alkynyl carbonyl compounds such as 1(pyrazine-2-yl)hex-1-yn-3-one 46, 1-(pyrimidine-2-yl)hex-1-yn-3-one 51 and 1(pyridine-2-yl)hex-1-yn-3-one 55. All the compounds 46, 51, successfully reduced to give the corresponding alkanes (47 & 48, 52, 56). After successful reduction of all the compounds mentioned above using SnCl2, we then introduced other reducing agents such as iron (Fe) and Zinc (Zn) powder, following different methods from the one of SnCl2, they were able to reduce the alkyne from 42 into the alkane 43 and gave the excellent yield of 65-100% when using Zn powder and range of 60-96% when using Fe powder. However, when we introduce compound 17, the reduction took place only on the nitro instead of alkyne.
Computational studies were carried out to understand the mechanism involved at a molecular level in a relevant ethyl acetate solvent. Geometric optimisation calculations have been performed in gaseous phase by employing density functional theory-based code gaussian with RB3LYP/6-311++G (d. p) basis set. Geometrical, thermodynamical, and molecular orbitals have been calculated to investigate structural and chemical behaviour of the molecules. Among the investigated pyrazine derivatives in gaseous phase, compound 46 was found to have highest negative energy value of -24.866 Hartree/atom with short bond length between C10≡C11 of 1.195 Å as compared to compound 47 and 48. The results revealed that compound 48 has a superior stability and lower chemical reactivity as compared to compound 46 and 47, since its corresponding energy gap between HOMO (-0.32937) and LUMO (0.17780) is lager, having Egap = 0.15157 eV
Mitigation of denial of service attacks in software-defined-cognitive radio network using software-defined-cognitive radio shield
Get PDFThesis (M.Sc.) -- University of Limpopo, 2023A ground-breaking approach to managing network resources is provided by softwaredefined networks that solve a number of management-related concerns. A novel paradigm called Cognitive Radio Networks (CRN) was developed to circumvent spectrum limitations. Methods for efficient dynamic spectrum access are employed. CRN allows secondary unlicensed users to take advantage of the licensed spectrum without interfering with authorized users. Security breaches on these networks are unavoidable. Network security planning is the first step in network defence. This study develops a strategy for software-defined cognitive radio networks that detect and counteract denial of service (DoS) attacks. We develop an intrusion detection system (IDS) to research the consequences of DoS attacks and mitigate DoS attacks in software-defined cognitive radio networks. The IDS is software based and is connected to the software-defined cognitive radio network's controller. We focus on the detection time, or the amount of time it takes to realize an attack has occurred, the payload, or the portion of malware the attacker wants the victim to receive, the jitter, or the variance in the time delay when a signal is transmitted and when it is received over a network connection, and the packet drop rate, or the number of packets lost during an attack. The round trip time and throughput indicate how quickly packets are transmitted during an attack. To generate the findings and compare them to existing schemes, we used NetSim which was installed on the Windows 10 Operating System. We proposed a scheme that detects and mitigates DoS attacks which performed well in terms of the jitter, throughput, detection time, round trip time, and packet drop rate. We compared our scheme to the SDN-Guard. Our scheme achieved less throughput, packet drop rate and round-trip time. Our scheme achieved faster detection time and lower jitter. The payload of our scheme was also less compared to the SDN-Guar