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GIS based spatio-temporal analysis of crime prevalence in Thulamela Local Municipality
No full textMENVSCDepartment of Geography and Environmental SciencesCrime is a serious problem with high social and economic costs in South Africa. It is neither unique nor random, but rather tends to be unevenly distributed and has a spatio-temporal pattern. The aim of this research is to analyse the spatial and temporal distribution of crime prevalence in Thulamela Local Municipality using Geographic Information Systems (GIS).
GIS applications were used to open new opportunities in crime control and prevention. The spatio-temporal distribution of crime in Thulamela Local Municipality was analysed using GIS tools. This research study adopted both quantitative and qualitative approaches to produce a more comprehensive study of the spatial and temporal distribution of crime in Thulamela Local Municipality. Data was analysed for various argumentations, i.e., spatial distribution of crimes, temporal trends, and identification of hotspots.
A Hotspot Analysis (Getis-Ord Gi*) tool was employed to unveil spatial clusters of crime prevalence. The analysis pinpointed distinct hotspots where crime incidents were significantly concentrated. The present study has found that crime incidences are influenced by various factors such as alcohol and substance abuse, domestic violence, illiteracy, poverty, unemployment, and self-enrichment. Thohoyandou was found to be one area with a high crime prevalence compared to Tshaulu and Mutale. Crime analysis did not only deepen our understanding of crime patterns, but also provided actionable insights on the types of crimes that happen in the different areas. By employing a diverse array of spatial and temporal analytical tools, I unearthed trends, clusters, and causative factors, understanding the socio-economic factors that play a role in the number of criminal activities that happen all over the country. As we continue to grapple with the multifaceted challenge of crime prevention, this comprehensive analysis serves as a foundation for data-driven strategies that can enhance public safety and well-being in Tshaulu, Mutale, Thohoyandou, and similar regions.NR
Ecology and phenology of Melia Azedarach Linn.on and off the Riverine Areas
No full textM.Sc. (Botany)Department of Biological SciencesNoteworthy, Melia azedarach Linn. is an indispensable tree species that is utilised in various forms. It can be used in craft industries as a substitute for teak wood when the supply is reduced. Simultaneously, its leaves, roots, bark, and flowers are used as medicines and natural pesticides. Melia azedarach Linn. is traditionally used as medicine to treat astringents and furthermore can be used against intestinal worms, skin diseases, stomachaches, uterine illnesses, and as a diuretic and febrifuge. In addition, it has been reported to possess anticancer, antimalarial, analgesic, and anti-inflammatory, antifungal, antibacterial and antioxidant activities.
This tree can adapt to different environmental conditions so that it can grow well in extensive areas. Melia azedarach Linn. is a plant that grows both on and off the riparian zones. Communities in South Africa see less value attached to it to the extent that in many places where these trees are found growing, the majority are cut for no good reason. Sometimes, the plant species is cut for the construction of fences, kraals, or firewood. The main reason for this practice is that much is not known about the plant; it could be found de-vegetated anytime.
The study was conducted at Ha-Tshikonelo, Thulamela Local Municipality, Limpopo Province, South Africa. Plant phenology and distribution have gained increased interest because climatic change is sensitive to phenological traits and their consequences for ecosystem function. It is made possible to gather information on spatial and ecological scales because of new technologies innovative technologies.
Temperature, photoperiod, and winter chilling are examples of plant phenology drivers, and competition is included.
A smartphone ( Huawei Nova Y60) camera was used to take pictures of phenological changes when visiting the on and off riparian zones from August 2019 to December 2021. The research aimed to determine the different phenophases and distribution patterns of Melia azedarach in riparian zones. The Nearest-neighbour method of sampling individuals within a population of plants was used for data collection.
The collected data was then analysed using Analysis of Variance (ANOVA). It was found that Melia azedarach Linn. is regularly distributed for both on and off-riparian areas. Phenophase occurring off riparian zones was found to be occurring earlier than in riparian zones. It was found that Melia azedarach Linn. is surviving and flourishing in both off and on the riparian zones. On riparian zone individuals were growing bigger than those found off the riparian zones because of the abundant supply of resources such as water and nutrients.National Research Foundation (NRF
Synthesis, photoisomerization and antimalarial activities of cinnamoyl chloroquinoline hybrids
No full textM.Sc. (Chemistry)Department of ChemistryThe primary aim of this project was to synthesize a series of cinnamoyl chloroquinoline hybrids employing a technique of molecular hybridization. Cinnamoyl chloroquinoline hybrids are compounds with the heteroaromatic core of amino-7-chloroquinoline, linked to differently substituted cinnamic acid groups by flexible primary diamines. In this study, three series (n=2, 3 and 6) of nineteen cinnamoyl chloroquinoline hybrids 18-36 were successfully synthesized by modifying known conventional methods with yields ranging from 24-74%. The structures of synthesized compounds were characterized by a combination of 1H NMR, 13C NMR, HRMS and IR analysis.
Hybrids 18-36 were found to isomerize when exposed to light to form mixture of cis and trans isomers. Through chromatographic mass spectrometry (LC-MS), these isomers were studied and LC-Q-TOF-MS/MS analyses of the photo-products revealed the emergence of cis isomer which eluted before its synthesized trans counterpart, suggesting a reduced polarity. The polarity of the compounds was significantly influenced by the nature of the substituents attached to the phenyl ring. Electron-withdrawing groups such as Cl, NO2, and F increased polarity in contrast to electron donating group OCH3 which reduced polarity. The concept of photoisomerization of cinnamoyl chloroquinoline hybridswere validated by the measurement of the transformation of trans to cis isomers using 1H NMR.
Compounds 18-36 were tested against wild-type drug-sensitive strain (NF54) and multidrug-resistant isolate (K1) of the human malaria parasite Plasmodium falciparum. Compounds with longer alkyl carbon chain linkers demonstrated greater antiplasmodial activity compared to those with shorter chain linkers. The in vitro studies revealed that compound 32 showed the most potent activity (in vitro 50% inhibitory concentration, 0,012 μM for strain NF54 and 0,009 μM for strain K1 and resistance index of 0.717 as a potential antimalarial agent. Other compounds (compounds 34 and 35) also showed moderate activity against a CQ-sensitive strain (NF54) and superior activity against a CQ-resistant strain (K1) of Plasmodium falciparum.National Research Foundation (NRF
An investigation of property and inheritance rights of the spouses in polygnous customary marriages among Vatsonga people in Vhembe District
No full textM.A. (Anthropology)Department of Arts and Social SciencesThis study sought to explore the proprietary consequences of the Vatsonga customary marriages. The study seeks to investigate the constitutional rights of the spouses in polygynous customary marriages, as well as to explore the property and inheritance rights of spouses in polygynous customary marriages and to investigate how spouses of polygynous customary marriages can be informed about their rights and be protected from losing their property and inheritance. A qualitative exploratory design was adopted in this study. Non-probability purposive and snowball sampling methods were used to select second women married in polygynous marriages. All participants live in the Vhembe District. It was envisaged that a sample size of five women and five husbands married in polygyny would be interviewed. A voice recorder was used to record data from the participants. An interview guide was used to explore property and inheritance rights from spouses of polygynous customary marriages. The data was transcribed verbatim and analysed using Tech’s ten steps of open coding. The study adopted two theories, for example, the resilience theory and the social exchange theory in integration with the study.. The researcher, through probing, realised that there is a need for the HMA to educate people about these marriages and help them through registering them so that their marriages can be recognised. Also, the community can empower women so that they can stand up for themselves and avoid the issue of them being under someone. Also, the issue of counselling and guidance, if there might be issues like disputes, so that they can be resolved in harmony.NR
Mahlamari eka Xitsonga hi ku kongomiso eka manwana ma matsalwa ma mitlangu
No full textPh. D. (Xitsonga)Department of African LanguagesDyondzo leyi yi lavisisile mahlamari eka Xitsonga, xihluvi xa mbulavulo lexi nga si lavisisiwaka hi vuenti. Ku tirhisiwile endlelo ra nkoka ku hlengeleta, ku hlamusela, na ku xopaxopa mahungu ma ndzavisiso hi tlhelo ra xivumbeko, tinhlamuselo na vulongoloxamarito. Nhlengeleto wa mahungu wu endliwile hi ku tirhisa endlelo ra khophasi hi ku tsavula marito, swivulwahava na swivulwa leswi nga na mahlamari kusuka eka matsalwa ma mitlangu ma Xitsonga lama landzelaka: Mavondzo a ya Hakeri (1981) hi F Rikhotso, Matlhari Hansi (1998) hi M.G Magagane, Mahlo ya Nkwahle (1999) hi O.R Chauke, Byi le tintihweni (2005) hi C.M Lubisi, Ndzi ta fa ndzi dyile (2005) hi K.J Ngobeni na S.J Malungana, Mathayere Mbuya! (2005) hi V.D Salane, T.M Rikhotso na S.J Malungana, Xivoni xa Vutomi (2008) hi I.S Shabangu, Vukosi i Mberha (2008) hi P Ndlovu, na Vadyondzi va namuntlha (2015) hi S.E Makhubele. Eka ntirho lowu ku tirhisiwile sampula yo hlawula hi xikongomelo xo kuma mahungu ma ndzavisiso, lama endzhaku ma nga xopaxopiwa hi ku tirhisa endlelo ro xopaxopa hi ku landza mikongomelo (thematic analysis). Ndzavisiso lowu wu endliwile hi ku landza rimba na mianakanyo ya thiyori ya R.M.W. Dixon's Basic Linguistic Theory, leyi kongomisaka eka ku xopaxopa na ku paluxa swihlawulekisi swa ririmi. Eka ndzavisiso lowu, ku kumiwile leswaku mahlamari hi tlhelo ra xivumbeko ma aviwile hi swiyenge swimbirhi, ku nga mahlamari ma ntumbuluko na mahlamari ma mpfelelo. Eka mahlamari ma ntumbuluko, hi kume leswaku ma tala ku teka xivumbeko xa timofimi to tshunxeka, loko mahlamari ma mpfelelo wona ma tala ku teka xivumbeko xa timofimi to vumbana. Ku tlhele ku kumiwa leswaku mahlamari eka Xitsonga ma nga ha amukeriwa kusuka eka tindzimi tin’wana. Ndzavisiso lowu wu tlhele wu kuma leswaku tinhlamuselo ta mahlamari ti nga ha kombisiwa hi ku ya hi mitlhaveko leyinene na leyi nga riki leyinene. Mitlhaveko leyinene yi katsa ntwelavusiwana, ku tshinya, ku hoyozela, ku bumabumela, ku tsaka, mpfumelelano, ku hlohlotela, ku lemukisa, ku komba malwandla, ku tisola, ku tilondla, na yin’wana na yin’wana. Eka mitlhaveko leyi nga riki leyinene ku na leyi kongomisaka eka ku chava, ku chuhisa, ku khunguvanyeka, ku twa ku vava, ku delela, ku banga manyala, ku nyadza, ku rivala, ku tiputa na ku sandza. Mayelana na vulongoloxamarito, ku kumiwile leswaku mahlamari, ku fana na swihluvi swin’wana swa mbulavulo, ma va kona eka tindhawu to hambanahambana exivulweni, naswona ma tirha tanihi swivulwa leswi tiyimeleke, swilandzelandzhaku kumbe
swihetisi. Swikumiwa leswi hlengeletiweke eka ndzavisiso lowu i swa nkoka swinene naswona swi ta pfuna eka vatirhisi va ririmi lava navelaka ku kuma vutivi byo karhi mayelana na mahlamari eka Xitsonga.The National Institute for the Humanities and Social Sciences (NIHSS), Huvo ya Council for the Development of Social Science Research in Africa (CODESRIA), na The South African Centre for Digital Language Resources (SADiLaR
Probabilistic renewable energy modelling in South Africa
No full textPh.D. (Statistics)Department of Mathematical and Computational SciencesThe variability of solar power creates problems in planning and managing
power system operations. It is critical to forecast accurately in order to maintain
the safety and stability of large-scale integration of solar power into the
grid. Accurate forecasting is vital because it prevents transmission obstruction
and maintains a power equilibrium. This thesis uses robust models to
solve this problem by addressing four main issues. The first issue involves
the construction of quantile regression models for forecasting extreme peak
electricity demand and determining the optimal number of units to commit
at minimal costs for each period using the forecasts obtained from the developed
models. The bounded variable mixed-integer linear programming
(MILP) model solves the unit commitment (UC) problem. This is based
on priority constraints where demand is first met from renewable energy
sources followed by energy from fossil fuels. Secondly, the thesis discusses
the modelling and prediction of extremely high quantiles of solar power.
The methods used are a semi-parametric extremal mixture (SPEM), generalised
additive extreme value (GAEV) or quantile regression via asymmetric
Laplace distribution (QR-ALD), additive quantile regression with covariate
t (AQR-1), additive quantile regression with temperature variable (AQR-2)
and penalised cubic regression smoothing spline (benchmark) models. The
predictions from this study are valuable to power utility decision-makers
and system operators in knowing the maximum possible solar power which
can be generated. This helps them make high-risk decisions and regulatory
frameworks requiring high-security levels. As far as we know, this is the first
application to conduct a comparative analysis of the proposed robust models
using South African solar irradiance data. The interaction between global
horizontal irradiance (GHI) and temperature helps determine the maximum
amount of solar power generated. As temperature increases, GHI increases
up to the point that it increases at a decreasing rate and then decreases.
Therefore, system operators need to know the temperature range in which
the maximum possible solar power can be generated. The study used the
multivariate adaptive regression splines and extreme value theory to determine
the maximum temperature to generate the maximum GHI ceteris
paribus. Lastly, the study discusses extremal dependence modelling of GHI
with temperature and relative humidity (RH) using the conditional multivariate
extreme value (CMEV) and copula modes. Due to the nonlinearity
and different structure of the dependence on GHI against temperature and
RH, unlike previous literature, we use three Archimedean copula functions:
Clayton, Frank and Gumbel, to model the dependence structure. This work
was then extended by constructing a mixture copula model which combined
the Frank and Gumbel models. One of the contributions of this thesis is the
construction of additive quantile regression models for forecasting extreme
quantiles of electrical load, which are then used in solving the UC problem
with bounded MILP with priority constraints. The other contribution is developing
a modelling framework that shows that GHI converges to its upper
limit if temperature converges to the upper bound. Another contribution is
constructing a mixture of some copulas for modelling the extremal dependence
of GHI with temperature and RH. This thesis reveals the following key
findings:
(i) the additive quantile regression model is the best-fitting model for
hours 18:00 and 19:00. In contrast, the linear quantile regression model is
the best-fitting model for hours 20:00 and 21:00. The UC problem results
show that using all the generating units, such as hydroelectric, wind power,
concentrated solar power and solar photovoltaic is less costly.
(ii) the AQR-2 was the best-fitting model and gave the most accurate
prediction of quantiles at τ = 0.95, 0.97, 0.99 and 0.999, while at 0.9999-
quantile, the GAEV model had the most accurate predictions.
(iii) the marginal increases of GHI converge to 0.12 W/m2 when temperature
converges to 44.26 ◦C and the marginal increases of GHI converge
to −0.1 W/m2 when RH converges to 103.26%. Conditioning on GHI, the
study found that temperature and RH variables have a negative extremal
dependence on large values of GHI.
(iv) the dependence structure between GHI and variable temperature
and RH is asymmetric. Furthermore, the Frank copula is the best-fitting
model for variable temperature and RH, implying the presence of extreme
co-movements.
The modelling framework discussed in this thesis could be useful to decisioniii
makers in power utilities, who must optimally integrate highly intermittent
renewable energies on the grid. It could be helpful to system operators that
face uncertainty in GHI power production due to extreme temperatures and
RH, including maintaining the minimum cost by scheduling and dispatching
electricity during peak hours when the grid is constrained due to peak load
demand.DSI-CSIR Inter bursary Support (IBS) Programm
The Impact of Nandoni Dam construction on selected indigenous plant diversity: A case study in Thulamela Municipality within Vhembe District of Limpopo Province South Africa.
No full textMENVSCDepartment od Geography and Environmental SciencesThe study assessed the impact of Nandoni Dam construction on selected indigenous plant species (IPS) diversity: A case study in Thulamela Municipality within Vhembe District. The construction of Nandoni Dam started in 1998 and was completed in 2005. The research focused on the following three specific objectives: to examine the selected IPS diversity before dam construction, to determine whether some selected IPS diversity were protected after dam construction, and to assess the community’s perceptions on the need to develop long-term management plans for the conservation of selected IPS diversity.
The literature reviewed concentrated on the background of the study, problem statement, justification of the study, Environmental Impact Assessment (EIA), and other studies. Under the methodology of data collection and research design, both qualitative and quantitative methodologies were used. Primary data collection includes field surveys, interviews, and observations. Secondary data were collected from documentary reviews, library books, published articles, theses, etc. Permission was requested and granted by the traditional leaders of Tshiulungoma, Budeli, Dididi, and Mulenzhe villages, which were affected by the construction of Nandoni Dam.
For systematic data analysis, the researcher used Statistical Package for the Social Sciences (SPSS) Version 25, narrative, and ethnography. Government officials were visited and communicated face-to-face and telephonically. Ethical consideration was granted by UHDEC. Results: Documentation of selected IPS diversity before 1998; photos of submerged and protected selected IPS diversity after dam construction in 2005. Recommendation: Community environment alliance, public community education on EIA reports, and conservation of selected IPS diversity.University of Venda and National Research Foundation (NRF
Modelling the spatial distributions and water use of Mauritius thorn (Caesalpinia decapetala) and river red gum (Eucalyptus camal dulensis) using remote sensing and geographic information system techniques in the Vhembe Biosphere Reserve
No full textPh.D.(Environmental Sciences)Department of Geography and Environmental SciencesThere is a need for in-depth knowledge of the spatial distributions and water use by Mauritius thorn (Caesalpinia decapetala) and River red gum (Eucalyptus camaldulensis) in the Vhembe Biosphere Reserve (VBR). Three remote sensing imagery platforms were assessed in terms of their ability to classify land cover within the VBR accurately. Supervised classification of Colour Digital Aerial Imagery (CDAI), SPOT 6 and Worldview 2 images was done using Harris Environment for Visualizing Images (ENVI) 5.3 and Environmental Systems Research Institute (ESRI) ArcGIS 10.8.3 software. The Spectral Angle Mapper (SAM) algorithm was used for the three images to identify the best image for the species-level classification. The accuracy of the classifications produced by the three images was evident that had a Kappa coefficient of 0.757 (substantial strength of agreement) for CDAI, 0.80 (substantial strength of agreement) for Worldview 2 and 0.857 (almost perfect strength of agreement) for SPOT 6 imagery.
The classification performance of SPOT 6 imagery led to its use for species-level classification. The species-level classification produced an accuracy with a kappa coefficient of 0.8750 (almost perfect strength of agreement). The highly accurate performance of the SPOT imagery was used for subsequent analysis of variation in the distribution of C. decapetala and E. camaldulensis. The species-level classification shows an increased suitable habitat from west to east along the Soutpansberg mountain and riparian areas.
Stepwise Logistic Regression (SLR) and Maximum Entropy Modelling (MaxEnt) were used to show the distribution of C. decapetala and E. camaldulensis in the VBR. Twenty-one predictor variables split into environmental and remote sensing data were collected across two seasons (hot-dry, cool-dry) from seventy-four (39 presences and 35 absence sites) for E. camaldulensis and seventy-eight (32 presences and 46 absence sites) C. decapetala from fourteen belt transects and forty quadrants measuring 200 x 200m within the VBR. The stepwise logistic regression analysis shows that variables accounted for significant variations in C. decapetala and E. camaldulensis distribution. The model increases suitable habitat from west to east along the Soutpansberg mountain and riparian areas. The MaxEnt modelling produced an AUC of 0.811 for river red gum, the random, and 0.668 C. decapetala. The two
models' high performance indicates high accuracy for the predictability of spatial distribution at the global and local levels.
Water is used by IAPS using remotely sensed Evapotranspiration (ET) derivatives from the Food and Agriculture Organisation’s (FAO) Water Productivity Open-access Portal (WaPOR). ET products as a proxy for plant water focusing on E. camaldulensis and C. decapetala in the VBR. The study focused on the WaPOR remote sensing-based products, such as actual Evapotranspiration and Interception (ETIa) and Gross Biomass Water Productivity (GBWP). Analysing the relationship between water loss and biomass productivity products extracted from the FAO WaPOR platform at various spatiotemporal scales. WaPOR products enabled comparing plant water used by C. decapetala and E. camaldulensis within the Luvuvhu catchment. The correlation results indicate that plant water loss (ETIa) and plant productivity (GBWP) show a significant relationship that can be used to understand IAPS distribution. The analysis of the site and ETIa showed significant relationships between F (60.28) and P (0.000) between the ETIa for C. decapetala sites. In contrast, the analysis of GBWP did not show any significant relationship between F (0.85) and P (0.359). In the case of river red gum, analysis of variance (ANOVA) on the sites and ETIa showed significant relationships between F (33.9) and P (0.000) and the ETIa for C. decapetala sites. In contrast, the analysis of GBWP did not show any significant relationship between F (1.59) and P (0.212). Establishing the relationship between vegetation's evaporation and biomass components can broadly indicate how C. decapetala and E. camaldulensis proliferation affect the water use in the Luvuvhu River catchment. This was achieved using water, as represented by ETIa, and plant biomass production in the form of GBWP.
A synthesis of the results and provide possible frameworks that can be used for managing IAPS. A framework (Biotic, Abiotic, and Movement (BAM) Framework) that can be considered when using GIS, RS, and modelling to understand the distribution of IAPS was developed. Combining findings, providing recommendations and conclusions for conservation and management. We conclude that GIS, RS, and modelling can be used to monitor and assess the significant spread of IAPS in the VBR. We advocate the inclusion of GIS, RS, and modelling in the management of IAPS in protected areas.NR
The existence of the digital divide in African indigenous communities in accessing digital African Indigenous Games: a case study of Ga-Mamabolo oin Limpopo Province, South Africa
No full textM.A. (African Studies)Department of Indigenous Knowledge Systems and Heritage StudiesAfrican indigenous games are one of the valued cultural aspects in African indigenous communities. These games have always been part of the African indigenous people and resemble the African culture and provide benefits such as entertainment and social development. Cultures and societies are dynamic; therefore, African indigenous societies are currently witnessing life under digitisation. The adoption of digitisation in African indigenous communities has become inevitable, and this has been seen as an opportunity to preserve games. Even though the adoption of digitisation to preserve the African indigenous games appears to be efficient, there are challenges associated with it, such as the unequal access of the digital games, which is referred to as the digital divide. Therefore, this study aimed to find out how existence of the digital divide in Ga-Mamabolo affects access to digital African indigenous games. The study was underpinned by the Diffusion of innovations, Critical posthumanism, and Sankofa theories. This study adopted qualitative participatory action research framed by interpretivism and indigenous research paradigms. The data was co-generated with 8 co-researchers who were children, youth, indigenous knowledge holders, and digitisation experts from Ga-Mamabolo. The data was generated through three stages of participatory action, planning, action, and reflections through focused group discussions. The study showed that affordability, internet access, and programming language for games are triggers of the digital divide within the indigenous communities of Ga-Mamabolo. Furthermore, to effectively digitise the indigenous games and eradicate the digital divide, the study showed that knowledge transfer, methodological, and information sharing may need to be revised with the indigenous people involved in the process.NR
Evaluation of Gender Mainstreaming on the appointment process of senior management: A case study of the Office of the Premier in Limpopo Province, South Africa
No full textPh. D.(Gender Studies)Department of Youth in DevelopmentThe challenges of inequality in South Africa’s workplace are compounded by the legacy of the system of apartheid and colonialism. Gender inequality continues to exist even during the new dispensation despite the existence of national, regional and international legislation to address inequality. This study evaluated the extent of the implementation and enforcement of employment equity policies on the appointment of senior management officials at the Office of the Premier. The study adopted a feminist qualitative approach to collect data. The sample of the study comprised males and females in the Office of the Premier. Non-probability purposive sampling to identify and select Deputy Directors, Directors and Chief Directors was used as these categories of employees are in the pipeline and poised to take different senior management positions. Data was collected using interviews, focus group discussions and document analysis. Due to my position as the Chief Director working in the Office of the Premier, I relied on the process of reflexivity to question and analyse any biases I may have had in the process of collecting and analysing the data. Reflexivity is a process of continual internal dialogue and critical self-evaluation of the researcher’s positionality as well as active acknowledgement; and explicit recognition that this position may affect the research process. Collected data was analysed using thematic analysis. Ultimately, findings and recommendations from the study were shared with the Institutional Development Support Branch in the Office of the Premier for implementation by all sector departments in the Limpopo Provincial Administration.National Research Foundation (NRF