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Item AmLight - Maximizing Technological Advancements in Research and Education; Network Connectivity for Open Science between South Africa, the US, and South America(2024) Morgan, H; Inarra, J; Bezerra, J; Lopez, LF; Chergarova, V; Cox III, DAC; Alvarez, GE; Hazin, A; Pillay, Kasandra; Makan, Ajay K; Greaves, D; Shariff, A; Sullivan, PConnecting South and North America with Africa via a South Atlantic high performance Research & Education Network (REN) has become a strategic priority. Africa offers unique biological, astronomical, environmental, geological, anthropological, and cultural resources, making it a valuable partner in global research and education. Enhanced technological and social connections between the United States, Brazil, and Africa are advancing research in multiple disciplines. The high-performance networking infrastructure of AmLight-ExP, in collaboration with the South African National Research and Education Network, provides unprecedented resources for open science research and education communities. This paper presents the architecture, capabilities, and impact of the AmLight-ExP network, highlighting its role in fostering international collaboration and addressing significant scientific challenges.Item Comparing amplitude-based and phase-based quantum plasmonic biosensing(2024) Mpofu, Kelvin T; Mthunzi-Kufa, PatienceThe utilization of quantum resources can enhance the sensitivity of conventional measurement techniques beyond the standard quantum limit (SQL). The objective of quantum metrology is to enable such quantum enhancements in practical devices. To achieve this objective, it is essential to have devices that are compatible with existing quantum resources operating within the SQL. Plasmonic sensors are promising candidates among these devices since they are extensively employed in biochemical sensing applications. Plasmonic sensors exhibit a response to slight variations in the local refractive index, which manifests as a shift in their resonance response. This shift, in turn, induces changes in the amplitude and phase of the probing light. By utilizing quantum states of light, such as NOON states, squeezed states, or Fock states, to probe these sensors, the measurement noise floor can be lowered, enabling the detection of signals below the SQL. In this study, we compare two configurations of quantum plasmonic sensing: phase-based and amplitude-based. By considering the Quantum Cram´er Rao bound for both configurations, we demonstrate that the phase-based configuration can more effectively exploit the available quantum resources than the amplitude-based configuration. A limitation of this work is that it did not consider loss.Item Socio-technical insights deploying rural solar computer housings for informal learning and information access(2024-05) Gush, Kim L; Cambridge, Grant JThe deployment, maintenance, monitoring and long-term support of information and computing solutions in rural and under-resourced environments requires innovative thinking and an integrated approach to addressing the multi-faceted challenges of such an undertaking. This paper presents recent developments and ongoing challenges faced after an extensive period of real-world interactions with multiple solar-powered computer housing deployments in rural South African communities. The solar housings are complex cross-disciplinary socio-technical systems providing a versatile digital library and physical access to computer terminals. Technical, social, and external challenges need to be understood and overcome for the installations to have a meaningful impact on the communities. Examples from field deployments are described in order to highlight lessons learned and corrective actions that could be implemented to reduce socio-technical difficulties in both existing and subsequent deployments.Item Quantum enhancement in the limit of detection measurement of a phase-based plasmonic biosensor including loss(2024) Mpofu, Kelvin T; Mthunzi-Kufa, PatienceQuantum states of light allow for highly sensitive biosensing configurations, surpassing the limitations imposed by shot-noise. In this theoretical study, we focus on optical plasmonic sensors, which have extensive applications in disease diagnostics, including detection of diseases like HIV. Our investigation involves simulating the impact of quantum states of light, such as the NOON state and squeezed states, on enhancing the limit of detection in a plasmonic phase-sensing biosensor, surpassing coherent light states’ shot-noise limit. Specifically, we explore the use of quantum states to improve the limit of detection in phase-based biosensors for HIV detection, operating below the shot-noise limit. Through our analysis, we demonstrate that incorporating quantum states of light in surface plasmon resonance (SPR) biosensing leads to enhanced performance compared to classical states. Moreover, we take into account the impact of environmental losses in the biosensing setup, considering the real-world challenges in practical implementation. Our findings emphasize the potential of quantum SPR biosensors in the development of novel disease diagnostics devices.Item Second Life: Enabling a Student Special Interest Group through Decommissioned HPC Systems(2024) Beukman, M; Jumoorty, S; Faller, J; De Beste, E; Johnston, Bryan JThe prevalence of High Performance Computing (HPC) in scientific research continues to grow, and with this growth, the importance of HPC education and training also increases. However, limited access to advanced research computing resources continues to impede workforce development in resource-constrained environments. In this poster, we describe our student-run HPC special interest group at the University of the Witwatersrand in South Africa, and provide an overview of the practical benefits it provides for students. Our group leverages repurposed decommissioned HPC systems to enable practical hands-on experience with HPC and computing clusters for undergraduate students at our university. We further discuss our group’s approach to selecting and preparing teams for student cluster competitions, where historically we have enjoyed notable success.Item Operational satellite-based information services supporting monitoring and management of Southern Africa's coastal and estuarine environments(2024) Smith, Marie E; Vhengani, Lufuno MMARCOSIO, The Marine and Coastal Operations for southern Africa and the Indian Ocean project, is one of only two marine thematic consortia under the GMES & Africa programme. It represents twelve organization from eight countries around southern Africa and the Western Indian Ocean region – from Angola to Kenya and the Island states. The project provides daily-updated operational earth observation services that enables near-real time and long-term monitoring of sensitive coastal regions by providing relevant satellite-based information at appropriate latency and spatio-temporal scales, supporting decision-making, governance, and sustainable management of near-coastal marine industries and ecosystemsItem Ten years of the HPC Ecosystems Project: Transforming HPC in Africa for the past decade(2024) Johnston, Bryan J; Timm, Lara C; Macleod, David N; Poole, JThe Council for Scientific and Industrial Research (CSIR)’s National Integrated Cyberinfrastructure System (NICIS) plays a pivotal role in advancing two key initiatives that focus on developing cyberinfrastructure across the African continent: the Southern African Development Community (SADC) Cyberinfrastructure Framework, and the Square Kilometre Array (SKA) Partner Countries Big Data initiative. Within NICIS these initiatives are managed through the HPC Ecosystems Project, which has two primary objectives: dis tributing entry level High Performance Computing (HPC) systems by repurposing decommissioned tier-1 HPC systems, and cultivat ing a skilled HPC workforce across Africa. The first deployment of HPC systems under the project occurred in 2013, using repurposed hardware from the Texas Advanced Computing Center’s decom missioned Ranger HPC system. These systems were allocated to bolster research capabilities at local research institutes in South Africa and within partner countries of the SKA project across Africa. A decade later, at the close of 2023, the HPC Ecosystems Project has deployed 35 HPC systems in 11 countries and delivered more than 30 formal HPC training workshops to over 700 participants, surpassing 21000 total participation hours. There is an active and growing virtual community exceeding 230 HPC practitioners glob ally. This paper provides a high-level overview of the first ten years of the project’s lifespan; outlining the various approaches towards establishing sustainable cyberinfrastructure and HPC workforces in Africa. Included is a reflection on the challenges experienced, lessons learned, and progress made towards delivering cyberin frastructure resources and HPC training to resource-constrained environments.Item Aspects of Wind Tunnel Testing: Practices(2024) Morelli, Mauro FThis presentation focuses on various aspects of wind tunnels - their testing, types, processes, balances and model design and procurementItem ASTRAL pool of technologies: A technology validation perspective within the Atlantic Area(2024) Pias, M; Guterres, B; Orazi, G; Paris, M; Drews, P; Oliveira, V; Botelho, S; Duarte, N; Poersch, L; Smith, Marie EThis presentation focused on various issues within the aquaculture sector, as well as Integrated Multi-Trophic Aquaculture (IMTA) and ASTRAL Pool of Technology Innovations.Item Satellite-based information services supporting operational environmental risk mitigation in the southern African marine aquaculture sector(2024) Smith, Marie EThis presentation discusses the Southern African marine environmental conditions of the Southern Benguela upwelling system and the Agulhas Current. It also talks to the marine aquaculture in South Africa that includes abalone, mussels, oysters and finfish.Item Satellite-based information services supporting operational environmental risk mitigation in the southern African marine aquaculture sector(2024) Smith, Marie E; Halse, SThis presentation provides details on satellite-based information services supporting operational environmental risk mitigation in the southern African marine aquaculture sector.Item Enhancing public transport research through improved data quality and accessibility: A case study in Johannesburg(2024) Karsten, Carike; Beetge, Carla; Burger, Paul ADPublic transport is used by the majority of the South African population to commute between home, school, other amenities and their place of work. There is, however, a severe deficiency in the quality of public transport data in South Africa. The absence of a standardised public transport data system is detrimental to researchers and commuters who make use of this data. This paper examines the adverse effects of inadequate public transport data on research, public transport planning and urban planning. It highlights the challenges resulting from inadequate public transport data and its detrimental effects on decision-making. Furthermore, the paper highlights the myriad of benefits that standardised, and easily accessible transport data can bring. The paper’s goal is to demonstrate the critical need for enhanced public transport data in research and planning and discuss potential solutions for improving data availability. This will pave the way for a more informed and efficient approach to transportation policy and practice.Item Sustainability and Circularity Assessment(2024) Sánchez, I; Checa, D; Smith, Marie E; Gomiero, A; Enríquez, SAquaculture has a particular role to play in contributing to the transition to sustainable food systems, but also to the development of the bioeconomy and the circular economy” The environmental performance of the EU aquaculture sector can be further improved through the development of systems with lower environmental impact, such as integrated multi-trophic aquaculture systems (IMTA).Item Copernicus Marine Services(2024-09) Smith, Marie ECopernicus is a flagship programme of the European Union. It monitors the earth, its environment and ecosystems, and also prepares for crises, security risks and natural or man-made disasters. Copernicus is a full, free and open data policy and a tool for economic development. It can be regarded as a driver for the digital economy.Item EO Africa DUNIA platform(2024-09) Smith, Marie EDunia is being developed in partnership with a group of leading organisations, each with a proven track record of delivering excellence in the earth observation domain. Dunia is an all-in-one, easy to use processing and dissemination platform, that even works on mobile.Item Progress in using GIS and RS in mapping and monitoring of inland waters for reporting to the GBF 2030(2024-09-17) Van Deventer, HeidiThis presentation focuses on the significant impact of wetland on the environment, and the concern about it being threatened. A Global Biodiversity Framework (GBF) has been designed to combat these threats to plan and manage all areas pertaining to biodiversity loss and degraded ecosystems.Item The daily influence of eutrophication on pH in aquatic ecosystems(2024-01) Omarjee, Aadila; Taljaard, Susan; Adams, Janine B; Chetty, AshlenThe objectives of the study were (1) to investigate the influence of aquatic primary producer biomass on diurnal pH variability, and (2) to understand how different types of primary producers affect pH patterns.Item Evaluating the efficacy of laboratory ageing of asphalt mix binders as a prediction for field ageing(2023-10) O'Connell, Johannes S; Maina, J; Bredenhann, SJ; Marais, H; Komba, JA Performance-grade Binder Specification (SATS 3208) for South Africa was finalised after CAPSA 2015 and launched at CAPSA 2019. A key feature of the performance-graded binder specification is the regulation of binder performance after long-term ageing, which is simulated in the laboratory using the pressure ageing vessel (PAV). This paper reports how this simulated long-term ageing relates to the ageing of binders in continuously-graded asphalt surfacing mixes in the field. Samples of asphalt surfacing mixes were obtained from ten sites in Gauteng, South Africa, which were constructed 5 to 30 years ago and selected based on the availability of the original binders. An ageing profile was developed for the original binders by characterising their rheology in the original state, after rolling thin film oven (RTFO) ageing and pressure ageing vessel (PAV) ageing after 20 hours, 40 hours and 80 hours. The ageing profiles were compared to the corresponding recovered binders. Rheological parameters used for comparison were Softening Point and Flexural Creep Stiffness / m-Value from the Bending Beam Rheometer (BBR) test.Item Relating the rheology of recovered binders from asphalt surfacing in the field to their fatigue performance(2024-10) O'Connell, Johannes S; Maina, J; Bredenhann, SJ; Marais, H; Komba, JG*.Sind and TC are two of many rheological parameters that have been proposed as potential specification properties for control of fatigue performance for hot mix asphalt. This paper assesses the extent of correlation between the values of these parameters and the presence of cracking in the hot mix asphalt surfacing from 11 sites carefully selected to represent a wide range of fatigue performance over periods ranging from 5 to 20 years. The binders were recovered using a modified Abson recovery process that accurately represents the properties of the aged in-situ binder. Results indicate that TC correlates better with the condition of the asphalt surfacing, compared with G*.Sind. The results also demonstrate that although binder fatigue parameters may be an indicator of fatigue performance, the actual fatigue performance is also determined by other factors such as binder film thickness of the mix, traffic loading, climate and rate of ageing.Item An analysis of a cryptocurrency giveaway scam: Use case(2024-06) Botha, Johannes G; Leenen, LA giveaway scam is a type of fraud leveraging social media platforms and phishing campaigns. These scams have become increasingly common and are now also prevalent in the crypto community where attackers attempt to gain crypto-enthusiasts’ trust with the promise of high-yield giveaways. Giveaway scams target individuals who lack technical familiarity with the blockchain. They take on various forms, often presenting as genuine cryptocurrency giveaways endorsed by prominent figures or organizations within the blockchain community. Scammers entice victims by promising substantial returns on a nominal investment. Victims are manipulated into sending cryptocurrency under the pretext of paying for "verification" or "processing fees." However, once the funds have been sent, the scammers disappear and leave victims empty-handed. This study employs essential blockchain tools and techniques to explore the mechanics of giveaway scams. A crucial aspect of an investigation is to meticulously trace the movement of funds within the blockchain so that illicit gains resulting from these scams can be tracked. At some point a scammer wants to “cash-out” by transferring the funds to an off-ramp, for example, an exchange. If the investigator can establish a link to such an exchange, the identity of the owner of cryptocurrency address could be revealed. However, in organised scams, criminals make use of mules and do not use their own identities. The authors of this paper select a use case and then illustrate a comprehensive approach to investigate the selected scam. This paper contributes to the understanding and mitigation of giveaway scams in the cryptocurrency realm. By leveraging the mechanics of blockchain technology, dissecting scammer tactics, and utilizing investigative techniques and tools, the paper aims to contribute to the protection of investors, the industry, and the overall integrity of the blockchain ecosystem. This research sheds light on the intricate workings of giveaway scams and proposes effective strategies to counteract them.