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Item A conflict-aware placement of client VMs in public cloud computing(2015-03) Ratsoma , MS; Dlamini, MT; Eloff, JHP; Venter, HSThe usage and adoption of cloud computing as a public deployment model is continuously improving, regardless of the security issues involved. This can be attributed to the huge benefits that the cloud provides such as pay-per-use model, quick deployment, turn-around times, huge cost saving, flexible and on-demand self-service provision to cloud users. Since public cloud makes use of virtualisation technology, VMs belonging to clients who are in competition may be placed within the same physical infrastructure. This raises the issue around hosting VMs from clients who might be in direct conflict on the same physical infrastructure. Malicious clients could exploit and launch inter-VM attacks to leak confidential information with a competitive advantage. A lot could happen once confidential data is illegally disclosed to unauthorized users. This work makes an attempt to eliminate the confidential data leakage threat posed by inter-VM attacks within the cloud. Hence, it sets itself up to investigate and determine an approach to physically separate potentially conflicting client VMs within the cloud in order to mitigate the confidential data leakage threat posed by inter-VM attacks. In this paper, we propose a conflict-aware VM allocation and placement architecture that is implemented with an algorithm modelled using a Chinese Wall Security Policy for physical separation of VMs. The solution is abstracted and applied to different levels of conflict and different levels of the cloud; the data centres, clusters and physical nodes, hence optimizing allocation in terms of conflict of interest. This solution focuses on optimally allocating compute space to client VMs depending on their conflict of interest which then determines the separation distances between conflicting clients’ VM. This guarantees that clients who are in direct conflict will have their VMs placed very far from each other and VMs belonging to clients that are not in conflict may be placed within the same physical node.Item Evaluation of interlayer bond strength for C55 emulsion prime bituminous binders with aggregates(2024) Abejide, Samuel O; Pitso, Reatile IThe use of an environmentally and green friendly product for improved interlayer bond strength in recent times has gained interest in the construction industry. This study investigates the performance of the C55 Emulsion Prime when compared with the conventional MC30 prime in enhancing interlayer bond strength and overall adhesion potency with aggregate particles. The C55 Emulsion Prime is a bituminous-based binder designed to penetrate aggregate layers creating a cohesive bond that improves structural integrity and adhesion potency of the binder with aggregates. Through a series of laboratory tests conducted on the two samples, the study provides detailed results on the penetration depth, interlayer bond strength and application under wet conditions. The test results indicated that the C55 emulsion prime significantly enhanced interlayer bond strength with the G1 dolerite aggregate with notable improvement to moisturized or wet surfaces. The C55 Emulsion Prime demonstrates superior interlayer bond strength compared to MC30 Cutback Bitumen Prime in wet regions or when dry aggregate condition is not feasible. The C55 Emulsion prime has a rapid curing rate within 60mins of application to a wet surface making it an efficient protective layer over granular surfaces to adhere and form a good bond strength property with the asphalt layer. This superiority is evident in both the direct shear test, rolling bottle tests, penetration power test and Zeta Potential test making C55 Emulsion Prime a more reliable choice for enhancing pavement performance in accordance with environmental friendliness and climate change sequences. Furthermore, the adhesive strength of the emulsions can be determined by identifying the isoelectric point (IEP). IEP is the pH condition where the surface charge = 0 mV. The IEP of C55 is approximately at pH 4.1. The IEP of the MC30 has been extrapolated to be approximately at pH 2.1. Material where the IEP is at higher pH form the strongest bond because they have a high proton acceptability. It can be predicted that the C55 forms a stronger bond with the aggregate when compared to MC30.Item A survey on the application of blockchain technology for cyber-physical systems(2024) Nelufule, Norman; Senamela, Pertunia M; Shadung, Lesiba D; Singano, Zothile T; Masemola, Kelebogile B; Mangole, Tshegofatso CThis paper presents a systematic review of the literature on the application of blockchain technology to improve the security of cyber-physical systems. The objective of the article was to identify current challenges, evaluate existing solutions, and propose future research directions. A Preferred Reporting Items for Systematic Reviews and Meta-Analyses framework was used to ensure that the result of this comprehensive review is not biased. The results and key findings have highlighted that there is a potential usage of the blockchain technology to address security challenges in a cyber-physical systems, including data integrity, authentication, and secure communication. This survey paper concludes by presenting the recommendations for integrating blockchain technology into CPSs to enhance their security and resilience.Item An examination into prospective research areas concerning the safety of learner transport, specifically focusing on intentional harm (Conference Paper)(2024) Rathogwa, MashuduIn South Africa, as of 2018, the alarming statistic of one child being abducted every five hours highlights a pressing concern for the safety of school children. What compounds this issue is the stark inadequacy of school security procedures in place to thwart potential abductions. Criminal syndicates, notorious for their meticulous and thorough operations, often exploit schools by infiltrating them under the guise of concerned parents. Kidnappings and abductions cut across socioeconomic boundaries, impacting both the underprivileged and affluent segments of society. The motives of these kidnappers encompass physical violence, financial exploitation, and even the gravest outcome, murder. In response to this disturbing trend, this research aims to highlight the existing gaps in both the research and practical measures that can be taken to fortify school security protocols, ultimately ensuring the safety of learners against kidnappings and abductions.Item Parametrized quantum circuits for reinforcement learning(2024) Mpof, Kelvin T; Mthunzi-Kufa, PatienceResearch on quantum computing is still in its infancy, but it has a lot of potential uses. One topic with potential is machine learning, namely in the field of reinforcement learning. This work examines the integration of parametrized quantum circuits (PQC) into reinforcement learning (RL) algorithms, assessing the potential of quantum-enhanced models to solve classical RL tasks. It closely follows the example found on the TensorFlow website. This paper reviews applications of quantum reinforcement learning (QRL). We examine PQCs in a standard RL scenario, the CartPole-vl environment from Gym, using TensorFlow Quantum and Cirq, to evaluate the relative performance of quantum versus conventional models. In comparison to conventional deep neural network (DNN) models, PQCs show slower convergence and higher processing needs, even if they are still able to learn the task and perform competitively. After they are fully trained, the quantum models show unique difficulties during the early training stages and reach a performance stability level like classical methods. This study sheds light on the present constraints as well as possible uses of quantum computing in reinforcement learning, particularly in situations with intricate, high-dimensional settings that prove difficult for classical computers to handle effectively. As we look to the future, we suggest that investigating hybrid quantum-classical algorithms, developing quantum hardware, and using quantum RL for increasingly difficult tasks are essential first steps. The study presents findings from both a classical reinforcement learning algorithm and a quantum integrated reinforcement learning algorithm. To provide a reliable comparison between quantum reinforcement algorithms and their classical equivalents, further work remains. This work lays the groundwork for future advances in the field by investigating the viability and use of quantum algorithms in reinforcement learning, even if it is not particularly unique. The purpose of this work is to help newcomers to this emerging field of study.Item Comparison of the mutual information content between the polarimetric monostatic and bistatic measured RCS data of a 1:25 Boeing 707 model(2020) Cilliers, Jacques E; Potgieter, Monique; Blaauw, Ciara; Odendaal, JW; Joubert, J; Woodbridge, K; Baker, CJMany studies have suggested that a fully polarimetric radar or a bistatic radar can improve the classification and recognition of airborne targets due to enhanced target information. This paper makes use of the information theoretic concept of mutual information (MI) and investigates the comparison of the MI content between polarimetric monostatic and bistatic radar cross section (RCS) measurements of a 1:25 Boeing 707 scale model. It aims to quantify the increases in the MI content, and hence recognition performance, due to the additional reflected signals available in a fully polarimetric radar or in a bistatic scenario.Item 3D physical model study for proposed remedial works to the Port of Richards Bay breakwaters(2024-04) Wehlitz, Carl-Peter FV; Mabille, EugeneThe Port of Richards Bay is frequently subjected to extreme storm events where recorded wave heights can easily exceed five meters. Over the last two decades, these storms have caused significant damage to the port’s breakwaters. A 3D physical model study was commissioned with the objective to assess and verify the stability of four different strategies to repair and enhance the structural integrity of these structures. Results from this study showed that both breakwaters will ultimately fail if no major improvements to these structures are made. The repair options tested for the main breakwater included a comparison of two different toe designs, as well as comparing the performance of two different armour unit types. The outcome indicated that the repairs to the main breakwater will most likely entail a trenched toe design and an armour layer comprising of very large cubic-type blocks. While the repair options tested for the lee breakwater mostly entailed placing additional or larger armour units of the same type, it did allow the opportunity to optimise both the armour unit size and the coverage for an improved overall outcome.Item AFDB Project Video(2023) Steyn, MaronelThe video gives and overview of the project Phycoremediation as an adaptation measure for climate change vulnerability at rural wastewater treatment plants in Southern African development community countries. It shows images of the different treatment plants in the different partner countries where feasibility studies were completed and where the technology is implement in Malawi. The technology addresses the issue of overloaded wastewater treatment works in South Africa and together with that the eutrophication and our receiving water environments. It also helps with service delivery issues in South Africa.Item Towards a GDPR compliance assessment toolkit(2024-06) Ngobeni, Sipho J; Thwala, Ntombizodwa; Siphambili, Nokuthaba; Pantsi, Phumeza N; Molema, Bokang C; Lediga, Jacob L; Senamela, Pertunia MThe European Union's (EU) General Data Protection Regulation (GDPR) makes it illegal to collect, process, and store personal data unless it is done in accordance with the prescribed legal and regulatory clauses enshrined in the Act. Organisations face significant challenges in navigating GDPR requirements and assessing their level of compliance. In particular, failure to comply with GDPR may potentially expose the data Controller and Processor to steep legal penalties including possibly administrative fines of up to 20 000 000 EUR, or in the case of an undertaking, up to 4% of the total worldwide annual turnover of the preceding financial year, which is imposed by the Supervisory Authority. This paper presents the results of a minimum viable product, the GDPR Compliance Assessment Toolkit (GCAT). The main objective of the GCAT is to assist organisations to assess their current state of compliance to GDPR. Drawing from an experimental research and development approach, GCAT is then compared with other existing GDPR compliance assessment technologies. Comparative analysis results shows that GCAT simplifies and optimize GDPR compliance assessments.Item First-principle study of SiC(110)/Ti2AlV(110) surface and interface(2024-07) Tshwane, David M; Dima, Ratshilumela S; Maleka, Prettier M; Mogakane, Lethabo; Ngcobo, Thabani; Maphanga, Rapela RThe current work investigated the SiC(110)/Ti2AlV (110) interface using density functional theory. Adherence of the ceramic to the metal foundation is critical to the success of a metal/ceramic pair. Metal and ceramic must be compatible with each other in terms of chemistry, mechanics, heat, and appearance. To gain insight into the nature of the interface bonding and strength, the work of adhesion, density of states, work function, and Mulliken charge analysis were calculated using density functional theory and evaluated. The current results showed that the adhesion work for SiC/Ti2AlV interface depends on the interfacial distance. The covalent bonding properties of the atomic interface depend on the bond that forms between C-V and Al-Si. The DOS plot curves dropped at the Fermi level, indicating that Ti and V atoms lose electrons at the interface when they interact with Si and C atoms. The work function of the SiC/Ti2AlV (110) interface was found to be 4.473 eV, implying stable electronic state and chemical stability of the interface.Item A decentralized cyber threat information (CTI) sharing platform(2024-08) Singano, Zothile T; Mthethwa, Sthembile N; Ntshangase, Cynthia SEmbracing the changes in technology and cybersecurity is crucial especially for organisations. As the technology space evolves so does the techniques used by cyber attackers, it gets more sophisticated. For organisations to secure their environment, it is vital to collaborate with other organisations to fight against zero-day-attacks. This can be achieved through sharing cyber threat information. Most organisations are hesitant to share CTI because of trust. Therefore, this paper presents a DLT based CTI sharing platform, which presents a trust-less environment for sharing. The nature of DLT presents opportunities for sharing CTI in a secure and decentralized manner, thus allowing global collaboration.Item Digital forensics: A survey of emerging threats, challenges, and opportunities in smart grids(2024-08) Nelufule, Nthatheni; Masango, Mfundo G; Senamela, Pertunia M; Mawela, Hunadi T; Latakgomo, Molebogeng; Moloi, Palesa MMThe era of digital technology has been introduced into the environment of the smart grid, which in turn increases its vulnerability to cyber threats due to the interconnected and cyber physical nature. These potential cyberthreats may interrupt the process of energy distribution, which may also jeopardize the essential grid infrastructure, causing enormous damage. The existing digital forensic frameworks are not equipped to address digital forensic issues within the complex smart grid environment. In this work, we present an assessment of the limitations of the existing digital forensic frameworks and technologies over smart grid settings. The main emphasis of this article is to analyze the unique issues in the smart grid network by conducting a systematic review of the literature. In addition, some of the real-life case studies have been discussed in the quest to demonstrate how other frameworks have been exploited to address these pressing challenges.Item Material Characterisation and Design of Alternative Pavement Surfacing for Steep Hilly Sections of Low-Volume Roads in Ghana(2024-01) Anochie-Boateng, J; Debrah, EK; Mvelase, Gculisile M; Agyekum, P; Asenso-Gyambibi, DIdentifying appropriate pavement design options for higher-risk sections of low-volume roads is a crucial 3 part of Ghana’s strategy to improve sustainable all-season rural access. This paper investigates the 4 suitability of alternative surfacing for steep hilly sections of low-volume roads in Ghana with gradients 5 above 12%. Typically, these roads are constructed with weak natural gravel as the wearing course. To 6 address the persistent drainage and erosion problems on these steep sections, four alternative rigid 7 pavement options were designed and proposed. These were interlocking concrete block paving (ICBP), 8 roller compacted concrete (RCC), thin mesh reinforced concrete (TMRC), and non-reinforced concrete 9 (NRC). We present the material selection, pavement designs, and life-cycle economic analysis of these 10 four cost-effective pavement options. The present worth of cost life-cycle cost appraisal of the options 11 considering the initial cost, probable maintenance cost, and salvage value of the road asset over a 25-year 12 service life, with a pavement design life of 15 years and an analysis period of 25 years are discussed. The 13 results indicate that all four alternative surfacing types are economically feasible and comparable, 14 although RCC has the lowest cost, while the ICBP option is relatively the most expensive.Item A survey of digital forensic tools for Android and iOS smart phones(2024-09) Ntshangase, Cynthia S; Nelufule, Nthatheni; Mulihase, Nkgomeleng D; Mtshali, Mamello L; Mokoena, Chantel JM; Moloi, Palesa MMMobile theft has been an increasing problem in South African cities and townships. This is also motivated by the black market for cellphone sales, but it has recently emerged that in many instances, the phone is stolen to harvest the credential and defraud and clean the victims’ bank account. Such cases are hardly reported as the success rate of prosecution is low. This is due to the lack of capacity, investigative tools, and the financial constraints of the investigative authorities. This paper presents a review of modern mobile forensic investigative tools, both open-source and commercialized. The purpose of this survey article is to present an analysis of tools in terms of their strengths and weaknesses and to simplify the work of investigators by bringing all the latest tools into one article.Item Software fault detection algorithms using artificial intelligence: A review and classification(2024-07) Ndlovu, Lungisani; Ntshangase, Ntomfuthi L; Mtshali, Mamello L; Makokoe, Mmamosweu PC; Myaka, Zanele S; Ndhlovu, Nomalisa; Khumalo, Lethukuthula P; Cossa, BhekiWith the rise of software applications, software development has become a rapidly evolving field, propelled by technological advancements and the increasing demand for innovative solutions to sustain our digital era. Consequently, detecting software faults has emerged as a critical attribute in the software development cycle to ensure system reliability, quality, and user satisfaction. However, traditional fault detection methods often suffer from drawbacks such as time consumption and error proneness, particularly in the context of large and complex software systems. In response to these hurdles, artificial intelligence (AI) presents itself as a promising methodology, with the aim of improving accuracy, scalability, automation, and proactiveness in fault detection. Therefore, this paper systematically reviews the literature on AI-based software fault detection algorithms. Using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) framework, a curated set of 50 peer-reviewed research publications was identified in Google Scholar and subsequently analysed using a classification coding framework. The findings reveal that AIbased software fault detection algorithms play an important role in improving software system reliability and performance.Item The implementation, deployment and roadmap of fog computing: A review(2024-07) Ndlovu, Lungisani; Stofile, Akhona; Makgafela, Dashney M; Miya, Sanele BOver the past few years, advances in computing and information technologies have significantly influenced and changed the way globalisation works or evolves over time. Today, users can access a wide range of high-performance and cost-effective services and resources through smart devices used in various environments, such as smart cities. With the spread of the Internet of Things (IoT), these smart devices can easily exchange information regardless of time or location. These devices are actively involved in the generation, collection, and exchange of real-time data. These data records are then transmitted, processed, and stored in the cloud. However, cloud computing is struggling to cope with the daily increase in IoT devices, especially those that require low latency, mobility support, geo-distribution, and location-based information. This paradigm fails to provide mobile services efficiently due to the considerable distance between cloud data centres and end-users. To address these challenges, Cisco introduced fog computing in 2012. The concept of fog computing extends cloud computing to networks closer to users. With this paradigm, IoT devices can perform some computational tasks locally on fog nodes, eliminating the need to transmit all data to remote cloud data centres for processing, analysis, and storage. This not only reduces latency but also saves bandwidth and resources. Therefore, this paper's objective is to identify opportunities and trends that can be exploited by implementing and deploying fog computing. Furthermore, the study aims to provide a roadmap for the implementation and deployment of fog computing.Item An Adaptive Digital Forensic Framework for the Evolving Digital Landscape in Industry 4.0 and 5.0(2024-01) Nelufule, NthaNthatheni Ntheni N; Singano, Zothile; Masemola, Kelebogile B; Shadung, Lesiba D; Nkwe, Boitumelo C; Mokoena, Chantel JDigital forensics is one of the most challenging disciplines in the field of cybercriminals. This article examines the evolving landscape of digital forensic investigations, identifies the unique challenges posed by emerging technologies such as Industry 4.0, and outlines a comprehensive approach not only to confront these challenges, but also to pave the way for a seamless transition to Industry 5.0. The proposed framework focuses on the development of an adaptive digital investigation framework customized for the evolving digital landscape in emerging technology environments. The framework combines dynamic evidence collection techniques, advanced analytics technologies, and multi-stakeholder collaborative engagement to ensure the fidelity and admissibility of the collected digital evidence. The analysis of the proposed framework has been discussed in detail using real-life case studies to ensure that the framework can be implemented and deployed in real-life scenarios.Item Challenges of adopting micro-credentials for skills development in South Africa: A literature review(2023-12) Mahlasela, Oyena N; Steyn, AASeveral studies reported the popularity of online education during the COVID-19 pandemic. Most people opted for short courses to develop new skills and reskill their capabilities. However, not everyone benefited from adopting micro-credential technologies, even though the literature emphasises the significant increase in online platforms. Therefore, this study investigated the challenges in adopting micro-credentials for upskilling or reskilling the workforce. A systematic literature review of fifty-five articles was conducted. After that, recommendations were formulated to assist employers and employees when adopting micro-credentials for skills development.Item Secure authentication using zero knowledge proof and biometrics: A review(2023-11) Ntshangase, Cynthia S; Baruni, Kedimotse P; Mahlasela, Oyena N; Matimatjatji, Rethabile M; Mgaga, Sboniso SSecure authentication is a very crucial feature to maintain privacy and security of sensitive data such as biometrics. Zero Knowledge Proof (ZKP) is one of cryptographic techniques widely used to improve privacy and security by allowing one party to prove to another party that they know a piece of information, without revealing the information itself. In this study, we conducted a review using the PRISMA framework to explore the use of ZKP and biometrics for authentication, its applications, and different protocols. Our findings highlight the significance of multi-party authentication scenarios and identify fingerprints, face, and iris as commonly used biometrics with ZKP. The Schnorr original method emerges as a widely employed ZKP protocol. Lastly, we provide future directions for leveraging ZKP in secure authentication systems.Item Economic analysis of a hybrid micro-grid with battery energy storage(2024-10) Ndlovu, Given; Oloo, Fiona RA; Moodaliyar, Sumendran; Hlalele, Thabo GThis paper presents a hybrid microgrid economic model that optimally schedules solar photovoltaic (PV) generation, wind, and battery energy storage power to meet the daily demand of the end-user. The model ensures that the hybrid power plant is fully utilized before acquiring additional power from the grid. An optimal scheduling model with the objective of maximizing the profitability of the hybrid micro-grid operator is evaluated while minimizing the unserved energy to the end-user. The economic scheduling model indicates that by using solar PV, wind, and battery energy storage, the hybrid micro-grid operator can achieve higher profits compared to when using solar PV and wind alone. The overall increase in profit is 3.7 times more than when using solar PV and wind generation, and the load unserved is reduced by 96%. The results show that energy storage can greatly increase profitability while reducing the load unserved.