• Smart microgrid energy market : evaluating distributed ledger technologies for remote and constrained microgrid deployments 

  Ledwaba, Lehlogonolo P.I.; Hancke, Gerhard P.; Isaac, Sherrin J.; Venter, H.S. (Hein) (MDPI, 2021-03-18)

  The increasing strain on ageing generation infrastructure has seen more frequent instances of scheduled and unscheduled blackouts, rising reliability on fossil fuel based energy alternatives and a slow down in efforts ...
• A comparative study of nonlinear regression and autoregressive techniques in hybrid with particle swarm optimization for time-series forecasting 

  Kuranga, Cry; Pillay, Nelishia (Elsevier, 2022-03)

  Usually, real-world time-series forecasting problems are dynamic. If such time-series are characterized by mere concept shifts, a passive approach to learning become ideal to continuously adapt the model parameters whenever ...
• Why is this an anomaly? Explaining anomalies using sequential explanations 

  Mokoena, Tshepiso; Celik, Turgay; Marivate, Vukosi (Elsevier, 2022-01)

  In most applications, anomaly detection operates in an unsupervised mode by looking for outliers hoping that they are anomalies. Unfortunately, most anomaly detectors do not come with explanations about which features make ...
• Feature selection using Benford’s law to support detection of malicious social media bots 

  Mbona, Innocent; Eloff, Jan H.P. (Elsevier, 2022-01)

  The increased amount of high-dimensional imbalanced data in online social networks challenges existing feature selection methods. Although feature selection methods such as principal component analysis (PCA) are effective ...
• Ukhetho : A Text Mining Study Of The South African General Elections 

  Moodley, Avashlin (University of Pretoria, 2019)

  The elections in South Africa are contested by multiple political parties appealing to a diverse population that comes from a variety of socioeconomic backgrounds. As a result, a rich source of discourse is created to ...
• On computer simulations, with particular regard to their application in contemporary astrophysics 

  Gruner, Stefan; Bartelmann, Matthias (Cosmos and History Publishing Co-op, 2020-10)

  In this survey contribution, which extends [GBa19], we consider and discuss computer simulations from a variety of perspectives with particular attention to computer simulations in astrophysics and cosmology. We begin by ...
• Model checking safety and liveness via k-induction and witness refinement with constraint generation 

  Timm, Nils; Gruner, Stefan; Nxumalo, Madoda; Botha, Josua (Elsevier, 2020-12)

  In this article, we revise our constraint-based abstraction refinement technique for checking temporal logic properties of concurrent software systems. Our technique employs predicate abstraction and SAT-based three-valued ...
• Visualising basins of attraction for the cross-entropy and the squared error neural network loss functions 

  Bosman, Anna Sergeevna; Engelbrecht, Andries; Helbig, Marde (Elsevier, 2020-08)

  Quantification of the stationary points and the associated basins of attraction of neural network loss surfaces is an important step towards a better understanding of neural network loss surfaces at large. This work proposes ...
• Nonlinear regression in dynamic environments using particle swarm optimization 

  Kuranga, Cry; Pillay, Nelishia (Springer, 2020-11)

  This paper extends a PSO-based nonlinear regression technique to dynamic environments whereby the induced model dynamically adjusts when an environmental change is detected. As such, this work hybridizes a PSO designed for ...
• A study of bi-space search for solving the one-dimensional bin packing problem 

  Beckedahl, Derrick; Pillay, Nelishia (Springer, 2020-10)

  Traditionally search techniques explore a single space to solve the problem at hand. This paper investigates performing search across more than one space which we refer to as bi-space search. As a proof of concept we ...
• Global optimisation through hyper-heuristics : unfolding population-based metaheuristics 

  Cruz-Duarte, Jorge M.; Ortiz-Bayliss, Jose C.; Amaya, Ivan; Pillay, Nelishia (MDPI, 2021-06)

  Optimisation has been with us since before the first humans opened their eyes to natural phenomena that inspire technological progress. Nowadays, it is quite hard to find a solver from the overpopulation of metaheuristics ...
• Analysing drivers’ preferences for privacy enhancing car-to-car communication systems : a study from South-Africa 

  Islami, Lejla; Fischer-Hubner, Simone; Hammond, Eunice Naa Korkoi; Eloff, Jan H.P. (Springer, 2021-04)

  While privacy-enhancing solutions for car-to-car communication are increasingly researched, end user aspects of such solutions have not been in the focus. In this paper, we present a qualitative study with 16 car drivers ...
• Digital forensics and the big data deluge — some concerns based on Ramsey theory 

  Olivier, Martin S. (Springer, 2020-08)

  Constructions of science that slowly change over time are deemed to be the basis of the reliability with which scientific knowledge is regarded. A potential paradigm shift based on big data is looming – many researchers ...
• Invited lecture : Notions of ‘theory’ and their practical consequences in the discipline of software ‘engineering’ (including information systems design) 

  Gruner, Stefan (South African Institute of Computer Scientists and Information Technologists, 2020)

  In the context of the AISSAC seminar on information systems, to which this invited lecture was given, it is presumed throughout the following considerations that: • contemporary information systems are software systems, ...
• The Fourth Industrial Revolution – what does it mean to our future faculty? 

  Marivate, Vukosi; Aghoghovwia, Philip; Ismail, Yaseera; Mahomed-Asmail, Faheema; Steenhuisen, Sandy-Lynn (Academy of Science of South Africa, 2021-05)

  The future of a country like South Africa is predicated upon policies; whether these policies are effective or ineffective is not primarily an issue. The prospects and realities of the Fourth Industrial Revolution (4IR) ...
• Use of available data to inform the Covid-19 outbreak in South Africa : a case study 

  Marivate, Vukosi; Combrink, Herkulaas (Committee on Data for Science and Technology (CODATA), 2020-05)

  The coronavirus disease (COVID-19), caused by the SARS-CoV-2 virus, was declared a pandemic by the World Health Organization (WHO) in February 2020. Currently, there are no vaccines or treatments that have been approved ...
• Towards a generalised metaheuristic model for continuous optimisation problems 

  Cruz-Duarte, Jorge M.; Ortiz-Bayliss, Jose C.; Amaya, Ivan; Shi, Yong; Terashima-Marin, Hugo; Pillay, Nelishia (MDPI, 2020-11-17)

  Metaheuristics have become a widely used approach for solving a variety of practical problems. The literature is full of diverse metaheuristics based on outstanding ideas and with proven excellent capabilities. Nonetheless, ...
• Genetic programming-based regression for temporal data 

  Kuranga, Cry; Pillay, Nelishia (Springer, 2021-09)

  Various machine learning techniques exist to perform regression on temporal data with concept drift occurring. However, there are numerous nonstationary environments where these techniques may fail to either track or detect ...
• Toward the visual understanding of computing curricula 

  Takada, Shingo; Cuadros-Vargas, Ernesto; Impagliazzo, John; Gordon, Steven; Marshall, Linda; Topi, Heikki; Van der Veer, Gerrit; Waguespack, Leslie (Springer, 2020-09)

  Various computing subdisciplines, such as computer science and software engineering, each have their own curricular guidelines. They can be very difficult to understand and compare for people such as prospective students, ...
• Dynamic multi-objective optimization for financial markets 

  Atiah, Frederick Ditliac (University of Pretoria, 2019)

  The foreign exchange (Forex) market has over 5 trillion USD turnover per day. In addition, it is one of the most volatile and dynamic markets in the world. Market conditions continue to change every second. Algorithmic ...

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