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Welcome to ResearchSpace, the institutional repository of the CSIR. ResearchSpace is an open access electronic archive collecting, preserving and distributing scholarly digital materials created by the CSIR.

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Practical deployment of a private NB-IoT network with open-source platforms

(2026-08) Makhalanyane, Thapelo; Hlabishi, Kobo I

Narrowband Internet of Things (NB-IoT) has emerged as a Low Power Wide Area Network (LPWAN) technology for industrial and enterprise IoT applications, offering licensed spectrum operation with guaranteed Quality of Service (QoS). This work presents a comprehensive, step-by-step guide to deploying a private NB-IoT network using open-source platforms. Existing literature on open-source NBIoT implementations is reviewed, and candidate platforms, including OpenAirInterface (OAI) and srsRAN, are evaluated against commercial solutions. A suitable open-source NB-IoT prototyping platform is then selected based on its demonstrated compatibility with commercial offthe-shelf (COTS) user equipment and robust support for 3GPP Release 13/14 features. The complete system architecture is detailed, including the eNodeB implementation on USRP B210 software-defined radio hardware and its integration with a lightweight Evolved Packet Core (EPC) optimised for IoT applications. A comprehensive testing methodology is employed to progressively validate the system, from basic signal generation and synchronisation through broadcast channels and random access procedures to end-to-end data connectivity. Experimental results using commercial off-the-shelf equipment demonstrate successful deployment, achieving a measured uplink throughput of 11 kbps, a downlink throughput of 17 kbps, and latency ranging from 300 ms to 15 s, depending on signal conditions. This work provides researchers and practitioners with a fully reproducible framework for establishing cost-effective private NB-IoT networks suitable for industrial automation, smart agriculture, environmental monitoring, and enterprise IoT deployments.

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Dry sliding wear behaviour of laser cladded altisicrco high entropy alloy coatings on Ti6Al4V: influence of CR/CO and AL/TI enrichment

(2026-08) Raselabe, KM; Makhatha, ME; Makoana, Nkutwane W; Skhosane, Besabakhe S

This study investigated how compositional variation within the AlTiSiCrCo high-entropy alloy (HEA) system affects the microstructure, hardness, and dry sliding wear behaviour of laser-cladded coatings on Ti6Al4V. Three coatings, namely, equiatomic (HEA 1), Cr/Co-enriched (HEA 2), and Al/Ti-enriched (HEA 3), were characterized by SEM, EDS, XRD, and Vickers microhardness and tested for dry sliding wear using a ball-on-disc tribometer at 5 N and 15 N. All coatings comprise a BCC solid solution matrix reinforced by intermetallic precipitates. HEA 2 and HEA 3 gave the highest hardness (755 HV and 754 HV, respectively) against 705 HV for HEA 1 and 345 HV for the Ti6Al4V substrate. All HEA coatings reduced wear rate relative to Ti6Al4V; HEA 2 recorded the lowest rate (4.570×10−5 mm3/N.m and 2.744×10−4 mm3/N.m at 5 N and 15 N, respectively), well below the substrate (2.257×10−4 mm3/N.m and 0.0014 mm3/N.m at 5 N and 15 N, respectively). Worn surface analysis showed abrasive/delamination at 5 N transitioning to more severe abrasive, adhesive, and delamination wear at 15 N. The enhanced wear resistance of HEA 2 stems from the BCC solid solution strengthening, intermetallic reinforcement, and high chromium content, which aids in the formation of the Cr2O3 protective oxide film. Overall, enriching the coating with chromium and cobalt proved to be the most effective approach for improving the tribological performance of laser-cladded AlTiSiCrCo HEA coatings on Ti6Al4V.

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Assessing institutional readiness for implementing the National Language Policy Framework for public higher education institutions in South Africa

(2026-06) RavyseI, N; Van Dyk, T; Wilken, Ilana; Du Plessis, D

This article investigates the institutional readiness of South African public higher education institutions for the implementation of multilingual language policies, specifically focusing on the recently promulgated National Language Policy Framework for Public Higher Education Institutions (NLPFPHE). Drawing on applied linguistics, Weiner’s (2009) theory of organisational readiness for change, and policy implementation studies, the authors explore how various institutional factors shape the capacity to implement language policies effectively. Using a mixedmethods approach, data from the national language audit (Van Dyk, Wilken, Ravyse, Du Plessis, Khumalo and Steyn, 2023) to assess current preparedness is analysed. The findings highlight key areas where institutions demonstrate readiness, such as staff engagement with policy, but also expose critical gaps in resources and student awareness. Moreover, the authors advocate for applying organisational readiness theory as a framework for guiding language policy implementation without specific models from the Department of Higher Education and Training (DHET). By outlining challenges and opportunities in the current landscape, this article offers practical insights for institutions that foster linguistic inclusivity and excellence. It aims to empower stakeholders with a structured approach to assess readiness, address gaps, and enhance the implementation of multilingual language policies.

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Quantum biosensing illuminates infected cells for timely disease diagnosis

(2026) Mthunzi-Kufa, Patience; Mpofu, Kelvin T

Photonics has a profound impact on daily life in numerous ways, from communication and entertainment to manufacturing and healthcare. In Africa, photonics applications in point-ofcare diagnostics, the diagnosis of substandard drugs, and treatments for cancer, diabetic wounds, and other ailments promise significant improvements in healthcare and the quality of human life. Of particular interest is that quantum technologies can be used for new forms of sensing, imaging, and computing, with potential applications in diagnostics and drug discovery. The amalgamation of biological molecules, such as deoxyribonucleic acid (DNA), proteins, or enzymes, with quantum sensors (QS), which illuminate changes in light emissions during lightmatter interactions, introduces a game-changer in rapid, sensitive, and specific disease diagnostics. Here, we theoretically demonstrate how the integration of quantum phenomena into sensing mechanisms could enable the detection of minute variations in intracellular factors, such as refractive index, cell morphology, and pH shifts in infected versus uninfected cells. We propose a conceptually designed quantum biosensing experiment that can be conducted using nitrogen vacancy (NV) centres.

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Using Landsat, Sentinel-1 and -2 and GEE to assess changes in wetland Ecosystem Functional Groups in the Maputaland Coastal Plain of South Africa

(2026-12) Apleni, P; Naidoo, L; Tsele, P; Van Deventer, Heidi

Consistent monitoring of wetland Ecosystem Functional Groups (EFGs) over large areas and long periods remains challenging owing to uneven availability, varying spatial resolutions, and spectral similarity of some EFGs. A Google Earth Engine (GEE)-based Earth Observation workflow was developed to map and quantify changes in wetland EFGs across the Maputaland Coastal Plain (MCP) in South Africa. The study included Landsat imagery for 1990, 2000, 2006 and 2014; and Sentinel-1 and Sentinel-2 imagery for 2018, 2020 and 2022.