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A carbon literacy for green innovation and entrepreneurship humanoid robot-assisted digital storytelling model
Get PDFThis thesis was submitted in fulfilment of the requirements of the degree of Doctor of Philosophy in Information Technology, Durban University of Technology, Durban, South Africa, 2025.Climate change has been negatively impacting our environment. The adverse effects of
climate change include flooding, drought, rising sea levels, hurricanes, and high
temperatures in different regions. The primary source of climate change is the release of
greenhouse gases into the atmosphere. Methane (CH4), nitrous oxide (N2O), and carbon
dioxide (CO2) are examples of greenhouse gases. Specific human activities contribute to
the emission of greenhouse gases into the atmosphere. Fossil fuel combustion is the
primary human activity responsible for greenhouse gas emissions. Carbon dioxide is the
most prevalent greenhouse gas, accounting for approximately 75% of global emissions.
This dominance of carbon dioxide in greenhouse emissions necessitated the concept of
carbon literacy to educate individuals and organizations on ways to reduce their carbon
footprint.
Robot-assisted digital storytelling is a digital storytelling method that uses social robots to
tell a story to audiences. From elementary schools to universities, robot-assisted
storytelling has been demonstrated to be an effective teaching method. However, no
published model exists for developers to create robot storytelling instruction or training.
Hence, this thesis proposes a robot-assisted digital storytelling model for carbon literacy
training. The study employed the design science research methodology for its activities.
The model development process started with the selection of articles that had been
published on robot storytelling. The selected articles were analyzed, and the procedures
and activities used to create robot storytelling were identified. Those activities and
procedures were synthesized to develop the proposed robot storytelling model. The
model was experimented with by using it to create digital storytelling, which trained
selected undergraduate students on carbon literacy. Similar training was delivered to
some students using a narrated PowerPoint presentation for comparison. The two pieces
of training were evaluated, and it was discovered that though both trainings improved
learning outcomes and motivation, the robot storytelling enhanced the participants'
knowledge of carbon literacy better than the narrated PowerPoint presentation. In
conclusion, this study proposed a six-element model that enhances learner motivation,
engagement, and learning outcomes in carbon literacy training.
On asymptotic behavior of galactic rotation curves in superfluid vacuum theory
Get PDFThe logarithmic superfluid theory of physical vacuum predicts that gravity is
an induced phenomenon, which has a multiple-scale structure. At astronomical
scales, as the distance from a gravitating center increases, gravitational
potential and corresponding spacetime metric are dominated by a Newtonian
(Schwarzschild) term, followed by a logarithmic term, finally by linear and
quadratic (de Sitter) terms. Correspondingly, rotation curves are predicted to
be Keplerian in the inner regions of galaxies, mostly flat in the outer
regions, and non-flat in the utmost outer regions. We compare theory's
predictions with the furthest rotation curves data points available for a
number of galaxies: using a two-parameter fit, we perform a preliminary
estimate which disregards the combined effect of gas and stellar disc, but is
relatively simple and uses minimal assumptions for galactic luminous matter.
The data strongly points out at the existence of a crossover transition from
flat to non-flat regimes at galactic outskirts
Nanotechnology revolution in diagnosing and treating urinary tract infections
Get PDFUrinary tract infections (UTIs) are among the most
common bacterial infections worldwide, affecting mil lions annually and imposing significant healthcare
costs. Rising antibiotic resistance among uropathogens
coupled with the limitations of culture-based diagnos tics and systemic therapies demands innovative ap proaches. Nanotechnology offers transformative po tential, enabling rapid, point of care (POC) detection
and targeted antimicrobial interventions that promise
to outperform evolving resistance mechanisms
Phase space formulation of density operator for non-Hermitian Hamiltonians and its application in quantum theory of decay
Get PDFThe Wigner–Weyl transform and phase space formulation of a density matrix approach are applied to a non-Hermitian model which is quadratic in positions and momenta. We show that in the presence of a quantum environment or reservoir, mean lifetime and decay constants of quantum systems do not necessarily take arbitrary values, but could become functions of energy eigenvalues and have a discrete spectrum. It is demonstrated also that a constraint upon mean lifetime and energy appears, which is used to derive the resonance conditions at which long-lived states occur. The latter indicate that quantum dissipative effects do not always lead to decay but, under certain conditions, can support stability of a system
Development of high surface area attrition-resistant spray-dried iron catalysts for Fischer-Tropsch Synthesis
Get PDFSubmitted in fulfilment of the academic requirement for the degree of Master of Applied Sciences in Chemistry, Durban University of Technology, Durban, South Africa, 2024.Iron is used as catalyst in the industrial process Fischer-Tropsch Synthesis (F-TS), which is a
catalytic chemical reaction that transforms synthesis gas (CO + H2) to create paraffins and olefins
for fuels and chemicals. This study aimed to design iron catalysts with a high surface area and
attrition resistance for F-TS. The following catalysts: α-Fe2O3, K/Cu/Fe and 0.367 M K/Cu/Fe
spray-dried at 200 °C were prepared using the co-precipitation, impregnation and spray-drying
methods. The catalysts were then characterized using various characterization techniques
including thermogravimetric analysis (TGA), Brunauer-Emmett-Teller (BET) analysis, scanning
electron microscopy (SEM), X-ray diffraction (XRD), and X-ray fluorescence (XRF). Attrition
resistance comprised physical tests with the accredited standard method of testing materials
(ASTM). The results showed that the 0.367 M K/Cu/Fe spray-dried at 200 °C catalyst has a large
surface area of 39 m2
/g and this could be attributed to the small particle size and the catalyst being
obtained in a powder form. The α- Fe2O3 catalyst was found to have more physical attrition
resistance with a value of 2.2 wt%/h. This was attributed to the small fines produced during the
physical attrition test, meaning that the catalyst has a high mechanical strength as compared to
other catalysts. The α-Fe2O3 catalyst was also found to have more chemical attrition resistance.
This was attributed to the minimum phase change that occurred during the reduction or activation
with CO as compared to other catalysts. All the catalysts including α-Fe2O3, K/Cu/Fe and 0.367 M
K/Cu/Fe spray-dried at 200 °C demonstrated good selectivity characteristics (low methane and
high C5+) hydrocarbons.This was ascribed to the iron carbide (χ‐Fe5C2) active phase or site, which
increased the chain growth and favoured the production of C5+ hydrocarbons while decreasing
methane selectivity. The α-Fe2O3 catalyst showed high activity and stability, as there was minimal
loss of catalytic activity as compared to other catalysts. This was as a result of less CO2 selectivity
produced by the catalyst, meaning that there was low water-gas shift activity (WGS) and the active
sites were less affected by the presence of water, which causes high loss of catalytic activity. The
activity and selectivity of the catalysts need to be improved before the industrial application.
The influence of the global pandemic (COVID-19) crisis on entrepreneurial innovation strategies amongst small and medium enterprises in Durban, KwaZulu-Natal
Get PDFSubmitted in fulfilment of the requirements of the degree of Master in Business Administration, Durban University of Technology, Durban, South Africa, 2025.It is evident and generally agreed by scholars around the world that Small and
Medium Enterprises (SMEs) are the backbone of any thriving economy. For the
SME sector to fully support the economic activities of a country, it needs to be
absorbed in innovation activities that deliver products and services valued by
customers. Studies conducted globally confirm a positive relationship between
SMEs and their characteristic innovative nature.
Paucity, however, remains in the local context of South Africa, particularly in Durban,
on what influences SME innovation strategies. It was thus the current study aim to
identify the influence of the global pandemic (COVID-19) crisis on entrepreneurial
innovation strategies among SMEs in Durban, KwaZulu-Natal. In addition, the study
recognized the impact of Corona Virus 2019 (COVID-19) on SME innovation, while
also examining post-pandemic innovation strategies by SMEs.
The study used a qualitative research design and structured interviews with openended questions, to gather data from respondents. Judgmental sampling
determined participants who used innovation strategies during COVID-19. The
sample size of the study was 15 SME owners/managers in Durban. With the closure
of certain businesses, the COVID-19 impact forced a shift from probability to
nonprobability sampling, as well as changes to the data collection initially planned
for the study. Therefore, SMEs in Durban that were allowed to operate were
targeted, where structured interviews were conducted to collect data from
respondents with the aid of a research assistant. Collected data were analysed
using thematic analysis.
The study results are presented in the form of coded themes, where the main
findings revealed the majority SMEs surveyed invest in technology. Furthermore,
the results showed agreement by the majority interviewed Durban SME
owners/managers that firm size influences innovation strategies, with strong
agreement the global COVID-19 pandemic significantly changed consumer buying
patterns. The research project additionally highlighted some of the most critical
factors that influence SME innovation strategies in Durban. Policy makers,
academics and SME stakeholders will find the study informative.
Evaluating the success rates of the Assessment of Professional Competence (APC) : insight and implications for professional development
No full textThis study examines success rates in the Assessment of Professional Competence (APC) for quantity surveyors
in South Africa, focusing on demographic influences on candidates’ outcomes. Employing a post-positivist
philosophical stance, the research uses a quantitative methodology to conduct a systematic analysis of institutional
records from the South African Council for the Quantity Surveying Profession (SACQSP). Data from 2019 and
2020 APC assessments were analyzed based on race, gender, and geographic location, providing a comprehensive
view of success rates across demographic groups. Additionally, this study assesses the impact of the Professional
Skills Modules (PSM), designed for candidates without an accredited Honours degree, on APC outcomes.
Statistical tests, including binary regression and Chi-square, were utilized to identify potential patterns and
disparities in success rates. Findings suggest that demographic factors may influence APC outcomes, highlighting
the need for measures that ensure fairness and accessibility in professional competency assessments. This research
contributes to the ongoing conversation about inclusivity and professional development within the quantity
surveying field, advocating for reforms that uphold excellence as the primary standard for achieving professional
recognition. Through these insights, the study aims to enhance support structures for current and future
professionals, fostering equitable opportunities in the evolving landscape of quantity surveying
Factors influencing equity financing within government entities in South Africa
No full textEquity financing theorsuggests that firms favour equity financing over debt to mitigate potential external risks and reduce exposure to external scrutiny. The aim of this study is to determine the extent to which various factors influence equity financing decisions within South African government entities. This study investigates the critical factors influencing equity financing decisions within government entities in South Africa. Employing Stata for data analysis, the research utilizes a cross-sectional, quantitative methodology supplemented by questionnaire-based data collection from 51 respondents. The application of Panels corrected standard errors (PCSEs) regression reveals a positive and significant relationship between risk appetite of the company (RAF) and company size (SIZE) with equity financing evidenced by P = 0.000 and 0.037, respectively. The links between reliance on internal funds (RIF) and equity financing is positive and slightly significant at 0.051 level. Based on these results, it is recommended that government entities assess their risk appetite and internal financial resources carefully when considering equity financing, ensuring alignment with strategic objectives and market conditions
Assessing the performance of green roofs for stormwater runoff mitigation in the South African urban environment
No full textRapid urbanization has altered the hydrologic cycle, causing increased runoff rates and
peak flows in the drainage system. Cities are now facing serious problems relating to
stormwater management such as water scarcity, degraded waterways, and increased
flooding. Under such circumstances, green roofs present numerous benefits including
the retention of rainwater for a longer time and a delay in the peak discharge. Using
data from various storm events, this study examined the performance of retrofitted
green roofs for stormwater management in the eThekwini region of South Africa. The
study also used the Personal Computer Storm Water Management Model (PCSWMM)
to investigate the effect that the best performing green roof would have on stormwater
flow rates and volumes for the region. The results concluded that the green roof
systems proved to significantly reduce stormwater runoff flow rates and volumes, and
retention largely depended on the intensity and duration of the rain events. The
PCSWMM model further confirmed that when compared to the base model, peak flow
rates from the green roof model decreased by over 40% for all storm intensities. It can
therefore be concluded that the implementation of green roofs within the eThekwini
Central Business District (CBD) will be highly effective in reducing peak stormwater
flow rates
Logarithmic wave-mechanical effects in polycrystalline metals : theory and experiment
No full textSchrödinger-type wave equations with logarithmic nonlinearity occur in hydrodynamic models of Korteweg-type materials with capillarity and surface tension, which can undergo liquid–solid or liquid–gas phase transitions. One of the predictions of the theory is a periodic pattern of density inhomogeneities occurring in the form of either bubbles (topological phase), or cells (non-topological phase). Such inhomogeneities are described by solitonic solutions of a logarithmic wave equation, gaussons and kinks, in the vicinity of the liquid–solid phase transition. During the solidification process, these inhomogeneities become centers of nucleation, thus shaping the polycrystalline structure of the metal grains. The theory predicts a Gaussian profile of material density inside such a cell, which should manifest in a Gaussian-like profile of microhardness inside a grain. We report experimental evidence of large-scale periodicity in the structure of grains in the ferrite steel S235/A570, copper C-Cu/C14200, austenite in steel X10CrNiTi18-10/AISI 321, and aluminum–magnesium alloy 5083/5056; and also Gaussian-like profiles of microhardness inside an averaged grain in these materials