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Item Refining binned aggregation of unevenly spaced, real-time data for visualisation and control(2015-11) Du Toit, Kirsten; Fogwill, Thomas; Maiwashe, T; Van der Westhuizen, MThe resource constrained environment in South Africa has led to an increased interest in the monitoring and control of electricity demand. The associated proliferation of smart meters/sensors and the collection of their data allows for monitoring and control of demand on a much wider scale than previously possible. A homeowner, business or utility may now make use of real-time data to track and control their electricity demand with potentially widespread economic effect. We examine the characteristics that a system must exhibit to excel at high volume, low latency real-time data stream processing to support such applications. A robust, scalable and fast method for real-time processing of streamed electricity demand data is suggested. This method also addresses the problems associated with developing countries in that the data received are sometimes inconsistent, unevenly spaced and interrupted. Processing these unevenly spaced data for visualisation is an important requirement in order for users to more easily understand and analyse their usage trends. Binned aggregation is explored as an effective strategy for minimizing the negative effects of inconsistent data of different frequencies. It is also used to reduce the data to manageable dimension, while real-time processing determines where and how to use the data. A sensor's data are stored in several rolling arrays of differing size that represent different time-frames. We keep the most detailed information for the current time-frame. The format chosen allows for data reduction yet allows redundant data to contribute to the model and refine the aggregation. The reduced amount of data stored allows fast retrieval of those data for visual display and analysis and improved scalability.Item A research agenda for studying evidence-informed practice in urban planning(2026-07) Du Toit, J; Pieterse, AmyThis article reviews empirical studies of evidence-based policy and proposes an agenda for studying evidence-informed practice in planning along three directions and overarching questions: What does ‘evidence’ mean to practitioners in different contexts and how do practitioners prioritize and use different forms of evidence? What is the effect of individual, institutional, systemic and political factors on evidence use? How can pragmatic evidence use be facilitated for deliberative practice, what is the efficacy of different approaches, and what are the procedural outcomes of cases of evidence use? This agenda could contribute towards a more systematic and integrated understanding of evidence-informed practice.Item Performance evaluation of NFPP-Type Sodium-Ion batteries(2026-05) Grobler, Inus; Banderker, Muhammad H; Govindsamy, Reesen; Van der Kolf, GideonThis paper presents a performance evaluation of next-generation sodium-ion cells employing Sodium Iron Pyrophosphate (NFPP) chemistry, which is now commercially available. Building on prior research into early-generation SiB technologies, the study investigates NFPP cells under varied operating conditions, including high and low temperatures, extreme C-rate discharge, and zero-volt storage. Results indicate that NFPP cells deliver exceptional high-power capability, sustaining continuous discharge rates up to 30C without degradation, and they exhibit strong thermal stability at elevated temperatures. While safety features such as zero-volt tolerance remain intact, low-temperature operation continues to pose challenges, particularly for charging, with irreversible capacity loss observed when exceeding manufacturer specifications. Despite a relatively low energy density (~79.75 Wh/kg), NFPP cells demonstrate significant potential for high-power applications requiring reliability and safety in harsh environments. These findings position NFPP chemistry as a critical step toward advancing sodium-ion technology for specialised energy storage solutions.Item Comprehensive validation of novel deep learning architectures to forecast geomagnetic substorms(2026-06) Essop, A; Mbatha, Nkanyiso B; Stephenson, JAEMagnetic substorms are disturbances in the terrestrial magnetosphere that can have significant space weather impacts, although forecasting their onset accurately remains an open problem. In this study, we develop multiple novel machine learning architectures based on convolutional neural networks, long short-term memory networks, extreme gradient boosting, and their hybrid combinations for the probability prediction of magnetic substorm onsets. The best performing models came from hybrids in the following order: two-dimensional convolution, bidirectional long short-term memory, and finally extreme gradient boosting for binary classification probability prediction with an F1 score of 0.8411 across both classes. Notably, a novel modified stratified K-fold cross-validation benchmark is developed for these deep learning models; the F1 scores fell within 79%–85% across model architectures. The results demonstrate the ability of models to unambiguously forecast substorm onsets from upstream solar wind and IMF conditions. Two-hr historical windows of solar wind velocity, proton number density, and three-dimensional interplanetary magnetic field components, sampled at 1-min cadence, are used to forecast the onset probability at the next minute after the window. The input data set was balanced using the SuperMAG list of substorm onsets between 2003 and 2022, with an equal number of non-substorm intervals, to avoid bias. Principal component analysis showed significant overlap in the solar wind and IMF conditions prior to both substorm and non-substorm intervals, indicating that these parameters alone may not be sufficient to forecast all substorms and that internal magnetotail preconditioning and magnetospheric processes are likely critical areas that should be explored further.Item Factors affecting the adoption of mobile-based digital technologies: Evidence from Ethiopia(2026-06) Bule, DL; Ntuli, Herbert; Gandidzanwa, CMobile phones and associated services possess substantial potential to improve household livelihoods. However, there is inadequate access to and use of mobile-based technologies, despite their potential to improve livelihoods in the Hadiya zone, Ethiopia. This study aims to analyse the main factors influencing the adoption of mobile-based technology. The analysis employed an ordered logit model on cross-sectional data collected from 278 respondents. The findings indicate that factors such as gender, education, affordability, access to remittances, social networks, awareness, geographical location, trade access, and type of mobile phone have positively and significantly influenced the likelihood of adopting mobile-based digital technology, except age. The implications suggest that mobile-based technology adoption remains under-utilised for essential activities, with adoption particularly lower among women and rural populations. Targeted interventions, including infrastructure improvements, digital connectivity enhancement, awareness campaigns, skill training, income-raising initiatives, and gender-sensitive digital policies, are essential to promote adoption.Item Ethnobotanical documentation and conservation assessment of medicinal plants in the Bojanala District, North-West Province, South Africa(2026-05) Matlala, ME; Sinorita, C; Kola, E; Ramarumo, Luambo J; Ndhlovu, PTBojanala District in North-West Province of South Africa is home to a diverse array of plant species, many of which are known for their medicinal properties. Despite their historical use, the pharmacological properties of these plants remain largely unexplored. The current study aimed to explore the phytomedicinal practices in Bojanala District by documenting medicinal plants and the associated indigenous knowledge.Item Integrating conductivity in stealth and biomedicine: Role of 3D printable polymers in next-generation technology(2026-07) Bandyopadhyay, Jayita; Ray, Suprakas SRecently, 3D printing has become a transformative force in manufacturing, especially for custom applications. It is reshaping industries like aerospace and healthcare. As technology advances, the demand for advanced functional materials suitable for 3D printing grows. This review focuses on electrically conductive polymers designed for 3D printing, especially fused deposition modeling It discusses their use in stealth and medicine. The review thoroughly examines the necessary criteria for these applications and the polymers and composites with various fillers developed to meet them. Understanding the performance and cost implications is crucial for future material development across many applications, both known and yet-to-be-discovered. Additionally, a perspective on the future of this technology is offered.Item Building the future of biophotonics through experiential education and seasonal schools(2026-06) Mthunzi-Kufa, P; Maphutha, J; Mcotshana, Zenande KS; Mcoyi, Michael PSignificance: Photonics represents a low-hanging fruit and a highly lucrative industry on the global stage, with applications spanning healthcare and biophotonics, energy and environmental photonics, agriculture and food systems, quantum photonics, telecommunications and data communications, among many other sectors. Despite this breadth of opportunity, the availability of structured biophotonics courses and programs remains limited, largely due to the inherently multidisciplinary nature of the field. Compounding this challenge, many schools, particularly in developing countries, lack adequate science laboratories, especially at the secondary level, thereby depriving learners of the practical exposure necessary to grasp fundamental theoretical concepts meaningfully. Aim: These gaps underscore the need for innovative and creative approaches to education and capacity development. Approach: Initiatives such as job-shadowing opportunities, outreach activities, summer schools, and diverse forms of online learning are therefore essential in widening access and building foundational skills. Results: Introducing photonics, optics, and biophotonics at the high-school and undergraduate levels would significantly strengthen the talent pipeline, cultivating scarce and highly sought-after skills. Conclusions: Against this backdrop, this paper highlights the importance of targeted strategies that advance biophotonics education and capacity building as a catalyst for sectoral growth.Item The role of digital technologies in enhancing construction safety: A case study of the George building collapse(2026-05) Molabe, Matshengwane P; Van Reenen, Coralie AIt is no secret that the construction industry faces ongoing safety challenges, with structural failures posing significant risks to lives and property. Digital technologies transform construction safety management by providing dynamic, data-driven alternatives to traditional, static methods. Studies report that 3D and 4D modelling tools enable clear, real‐time visualizations that improve hazard identification and safety planning. Digital platforms often integrated with Virtual and Augmented Reality also enhance worker training and safety communication, shifting the process from reactive, paper‐based approaches to proactive, continuously updated systems. This paper explores the role of digital technologies in improving construction safety by predicting and mitigating risks. A detailed review of existing literature, an analysis of the George building collapse, and an evaluation of BIM's potential contributions provide insight into how digital tools can revolutionize safety protocols in the construction industry.Item Characterisation of heat-treated Ti-rich NiTi fabricated by laser powder bed fusion(2025-11) Motibane, Londiwe P; Tshabalala, Lerato C; Becker, T; Kgomo, Matshela TNitinol (NiTi) is useful for biomedical applications, and laserpowder bed fusion (L-PBF) presents a unique opportunity to fabricate complex and patient-specific implant designs. The processing of nitinol via L-PBF, however presents a challenge as it results in an inhomogeneous microstructure that affects mechanical performance and can limit functional property performance. Moreover, an understanding of Ti-rich NiTi processed via L-PBF is lacking. Post-processing heat treatments are an avenue to alter and tailor the microstructure and thus influence the resulting phase transformations and mechanical performance. This paper presents various heat treatments and the influence of their resultant microstructures, phases and transformation temperature behaviour is characterised.Item Spatiotemporal air quality forecasting in South Africa using the LSTM model(2026-06) Shikwambana, L; Sebake, M; Molefe, M; Havenga, H; Mbatha, Nkanyiso BThis study applies a Long Short-Term Memory (LSTM) model to predict key air pollutants, i.e., sulphur dioxide (SO2), nitrogen dioxide (NO2), and particulate matter (PM2.5), as well as the Air Quality Index (AQI) across South Africa using satellite-derived observations. The analysis focuses on comparing original pollutant fields with model-generated predictions for two consecutive days, highlighting both spatial patterns and predictive performance. Results reveal a persistent and intense pollution hotspot over the Mpumalanga Highveld, driven by coal-fired power generation and industrial activities. Elevated pollutant concentrations in this region translate into AQI levels ranging from Unhealthy to Very Unhealthy, while most other parts of the country remain within the Good category. Spatial comparison between original and predicted fields shows strong agreement, with only minor deviations in areas characterized by steep emission gradients and localized plumes. Quantitative evaluation using RMSE (0.020390) and MSE (0.000416) confirms the high accuracy of the predictive model, with error values remaining extremely low across all pollutants and AQI outputs. PM2.5 exhibits the smallest errors (MSE = 4.230169 × 10−6), while slightly higher values for SO2 (MSE = 2.628 × 10−4) and NO2 (MSE = 1.39541 × 10−4) reflect the difficulty of capturing sharp spatial transitions associated with pointsource emissions. Despite these localized discrepancies, the model demonstrates robust skill in replicating both pollutant magnitudes and AQI classifications. Overall, the findings indicate that machine-learning approaches offer a reliable, high-resolution tool for air-quality prediction in South Africa and have strong potential for supporting operational forecasting, exposure assessment, and environmental policy development.Item Sources of water-soluble organic carbon in aerosols at the Cape Point GAW station(2026-07) Rawatlal, M; Spence, KAM; Smith, Marie E; Labuschagne, C; Altieri, KEAerosols play a major role in climate by influencing both radiative forcing and cloud condensation nuclei (CCN) formation, with organic aerosols comprising a large fraction of the global natural aerosol burden (∼20–70%). Despite this importance, long-term observations of water-soluble organic carbon (WSOC), particularly in size-segregated aerosols from natural sources, remain scarce in the southern hemisphere. Here, we present size-resolved WSOC measurements from an eight-month observational campaign (April to November 2018) at the Cape Point Global Atmosphere Watch (GAW) station, a remote coastal site at the southern tip of Africa, ideally suited for elucidating marine, continental, and mixed aerosol sources. Weekly aerosol samples were classified using air mass back trajectories, radon-222 and carbon monoxide concentrations, wildfire observations, and satellite-derived chlorophyll-a to assess source influences. Across all air mass classifications, WSOC concentrations were consistently higher in the fine mode (<1 μm) than in the coarse mode (>1 μm) aerosols (0.58 ± 0.55 μg/m3 vs 0.20 ± 0.22 μg/m3, respectively). Fine mode WSOC concentrations were highest during periods influenced by biomass burning (0.87 ± 0.49 μg/m3) and continental outflow, while marine and modified marine air masses exhibited lower fine mode WSOC concentrations. However, periods of enhanced marine biological activity were associated with increased fine-mode WSOC concentrations. The observed predominance of WSOC in the fine mode across marine, modified marine, and continental air masses highlights the importance of secondary formation and atmospheric aging processes, rather than direct primary emissions, in controlling WSOC concentrations at Cape Point. Overall, WSOC levels at this coastal site reflect an integration of natural and anthropogenic sources, transport history, and atmospheric processing. These results establish a regional baseline for WSOC aerosols in southern Africa and contribute to a broader understanding of organic aerosol formation in a data-sparse southern hemisphere coastal environment.Item Assessing biodiversity risks in African agriculture for the One Food Risk: A review of research trends through bibliometric analysis(2026-06) Maoela, Malebajoa A; Skhosana, Felix V; Luvuno, Linda B; Ntuli, Herbert; Mutanga, Shingirirai SFood systems are central to human well-being and food security, but are also major drivers of biodiversity loss through deforestation, land conversion, monoculture, and intensive agrochemical use. Guided by One Health philosophy and aligned with the One Food Programme, this study assesses biodiversity risks associated with African food systems. A bibliometric and narrative review of nearly 12,000 peer-reviewed studies was conducted to examine research trends, hazards, risks, impacts, and adaptation strategies related to biodiversity and agriculture in Africa. Results show increase on agriculture–biodiversity linkages since 2001, although, African researchers remain underrepresented and geographic coverage is uneven. Research is concentrated on terrestrial systems, while aquatic food systems, including fisheries and aquaculture, receive comparatively limited attention. Biodiversity risks linked to post-production stages of food systems, such as processing and distribution, are poorly studied. The findings further indicate that unsustainable intensification contributes to soil degradation, biodiversity loss, and declining ecosystem services, whereas practices such as agroforestry, intercropping, conservation agriculture, and integrated aquaculture can support resilience and sustainability. The study identifies major research gaps and highlights the need to integrate biodiversity risk indicators into the One Food Risk Tool to support evidence-based policies for sustainable and resilient food systems in Africa.Item Net zero carbon potential of bio-based building materials(2026-07) Van Reenen, Coralie A; Padayachi, Yerdashin RThis research paper explores the net zero carbon potential offered by bio-based building materials in South Africa, specifically, mass timber and two bio-based concretes, hempcrete and nonCrete. As the construction industry grapples with the urgent need to reduce its carbon footprint, bio-based materials offer a promising path toward sustainability. Hempcrete, known for its excellent insulation properties and carbon sequestration capabilities; nonCrete, making use of alien invasive species, thereby restoring natural systems; and mass timber, lauded for its strength and renewability, are analysed for their environmental benefits and practicality in modern construction. The study examines the cradle to gate carbon emissions of these materials, as well as fitness for purpose. Findings suggest that bio-based materials not only contribute to significant carbon savings during their production and usage phases but also enhance building performance. The study methodology compares the embodied carbon of a comparable section of wall of each material. Calculations are based on data available in embodied carbon databases, case studies and environmental product declarations. The paper finds that despite limited standardised data, the selected materials have net negative embodied carbon and concludes with recommendations for integrating these materials into mainstream construction practices to drive the industry towards a more sustainable future.Item Profiling motorcycle delivery riders: Insights from a baseline survey of riders in Pretoria, South Africa(2026-06) Dube, Mxolisi S; Kwange, Boniswa NThis paper profiled the demographic characteristics, working conditions, road safety behaviours, and crash involvement of 109 motorcycle delivery riders in Pretoria, South Africa, using a quantitative descriptive survey. The findings indicated that the sector was overwhelmingly male at 97% and predominantly young, with 62% of riders aged between 25 and 34 years. Most riders worked extended hours, with nearly 70% reporting more than 55 hours per week, and the majority, at 61%, relied on rented motorcycles, and 31% of them relied on company-owned motorcycles. Guided by the Theory of Planned Behaviour (TPB) and the Job Demand-Resources (JDR) model, the results revealed a contrast between high self-reported regulatory compliance and exposure-driven risk. Most riders, 97% of them, reported never riding under the influence of alcohol, running red lights at 83%, or riding without a helmet at 94%. However, time-pressure-related behaviours were evident, including frequent lane changing to overtake, reported sometimes by 39% of riders, mobile phone use while riding, reported always by 12%, and failure to maintain safe following distances, reported always by 11%. Crash involvement in the preceding 12 months was reported by 18% of riders, mainly involving light injuries or minor incidents. The findings highlight the need for targeted policy interventions, improved working conditions, rider training, and motorcycle-inclusive urban infrastructure.Item Leveraging open-source intelligence to combat cryptocurrency investment scams(2026-06) Botha, Johannes G; Berkman, A; Leenen, LThis paper presents a follow-up study to earlier research on cryptocurrency crime, again drawing on the case of an elderly woman defrauded by an online platform known as RSI-Platform. Whereas the initial study focused mainly on on-chain analysis within the blockchain environment, the present work shifts attention to off-chain approaches, applying open-source intelligence (OSINT) techniques to deepen investigations into crypto-related fraud. By systematically examining diverse input data—such as names, phone numbers, email addresses, and URLs—this study conducts link analysis and aims to build detailed profiles of potential suspects, thereby advancing understanding of the strategies and methods used in cryptocurrency scams. The analysis aims not only to trace the scammers’ digital footprints but also to reveal networks and connections to other fraudulent platforms that support these activities. Moreover, this research seeks to raise public awareness about the scale and operation of fake online investment schemes in the crypto sector. By exposing the vulnerabilities exploited by offenders and illustrating how OSINT can be used to detect and disrupt such scams, the paper adds to ongoing discussions on cybersecurity and consumer protection in the fast-changing field of digital finance. Additionally, the findings are intended to offer practical insights for law enforcement agencies, policymakers, and the wider public, encouraging a more informed and proactive response to the threats posed by crypto-related fraud.Item Shoreline extraction and coastal change detection from satellite SAR using thresholding based methods(2026-07) Erasmus, C; Haupt, Shelley A; Sibolla, Bolelang HCoastal erosion, which is the gradual loss of sediment over time, poses a significant threat to South Africa’s coastline. The monitoring and detection of coastal erosion is essential for the effective management of coastal environments and can be quantified by the delineation of coastal boundaries. Remote sensing techniques such as Synthetic Aperture Radar (SAR) offer an unique opportunity to extract shoreline positions over large areas of the coast. In this study, C-band SAR data was used to derive backscatter coefficients for three different areas of interest in the Eastern Cape province in South Africa over a ten year period. Thresholding and edge detection techniques were used to delineate shoreline positions. The coastal erosion and accretion trends were calculated and the results indicated that the Linear Regression Rate (LRR) for the three different study areas showed various coastal erosion seasonality trends. The shoreline LLR ranged between −0.01 and −3.28 m/year for the Cape Recife area and 0.17 and −4.78 m/year for the Nelson Mandela Bay beach front. The overall pattern was erosion during the winter months and accretion during the summer months. In contrast, for the Kings Beach area, there was a consistent accretion trend where the LRR values ranged between 0.94 and 1.68 m/year. The findings of this study suggest that SAR remote sensing and thresholding-based methods could be a suitable technique for detecting and monitoring coastal erosion seasonality patterns.Item Evaluating the rate of migration of an uranium deposition front within the Uitenhage Aquifer(1999-08-27) Vogel, JC; Talma, AS; Heaton, THE; Kronfeld, JThe solubility of uranium in groundwater is very sensitive to changes in redox conditions. Many secondary (sandstonetype) uranium deposits have been formed when soluble U has precipitated after encountering reducing conditions in the subsurface. In the groundwater of the Uitenhage Aquifer (Cape Province, South Africa), 238U-series isotopes were used to assist in studying the history of the reducing barrier. Uranium isotopes were used to determine the present position of the barrier. Radium and radon were used to evaluate the path of migration that the front of the oxygen depletion zone has taken over the past 105 years. During this time the reducing barrier has moved, leaving in its wake a trail of U in various stages of secular equilibrium with its daughter 230Th. The 226Ra daughter of 230Th is not very mobile. Its growth upon the aquifer wall is reflected in the Rn content of the water. This in turn, due to the relatively great age of the water, indicates the extent of the 230Th ingrowth (from precipitated U) that took place before the barrier migrated.Item Cape Point GAW Station Rn-222 detector: factors affecting sensitivity and accuracy(2002) Brunke, EG; Labuschagne, C; Parker, B; Van der Spuy, D; Whittlestone, SSpecific factors of a baseline Rn-222 detector installed at Cape Point, South Africa, were studied with the aim of improving its performance. Direct sunlight caused air turbulence within the instrument, resulting in 13.6% variability of the calibration factor. Shading the instrument eliminated this effect. A residual temperature dependence of the calibration factor was reduced to negligible levels with an improved photomultiplier tube. A superior detector head permits field servicing of the instrument, and has reduced one component of the instrumental background by a factor of 2. The other component probably constitutes thoron emissions from the stainless steel walls. The detection limit of the instrument could be reduced from its current 33 to 20 mBq m(-3) if the thoron were to be eliminated.Item A systematic literature review: The influence of technical, operational and structural factors on the adoption of digital agriculture among small-scale farmers in Sub-Saharan Africa(2026-07) Chesi, ALC; Cho, Moses A; Cho, MNA; Ramoelo, AThis systematic review paper examines how technical, operational, and structural factors influence the adoption of digital agriculture among small-scale farmers in Sub-Saharan Africa. Guided by PRISMA protocols, the study applies a hybrid thematic synthesis across six dimensions: technical, operational, policy and regulatory, governance, social and cultural, and environmental. The findings indicate that digital tools can generate substantial benefits, including yield increases of 10–30% (documented primarily for mobile-based advisory services and precision input management in East African horticulture and West African cocoa value chains) and price gains of 15–25%, with adoption rates of 70–80% in settings characterised by robust infrastructure, strong institutional support, and effective value chain integration. However, these benefits are unevenly distributed and tend to concentrate in “islands of adoption” characterized by robust infrastructure, strong institutional support, and effective value chain integration. While technical (94.9%) and operational (91.5%) factors dominate the literature, their impact is constrained by persistent structural barriers, including weak policy implementation (79.7%), fragmented governance systems (76.3%), and socio-cultural exclusion—such as gender disparities, age-related digital divides, and language misalignment (71.2%). The review identifies five minimum conditions for meaningful adoption: (i) affordable connectivity and access to digital devices; (ii) context-specific digital literacy; (iii) culturally relevant, user-centred design; (iv) robust institutional ecosystems; and (v) enabling policy and financial frameworks. Overall, the findings underscore that digital agriculture adoption is a socio-technical process shaped not only by technological innovation but also by institutional arrangements and user capabilities. Comparative cases, such as Kenya’s Farm.ink and the less successful EZ Farm initiative, further highlight the importance of integrated, context-responsive approaches to ensure that digital agriculture enhances, rather than marginalizes, small-scale farmers.