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In this paper, a laboratory experiment, which was developed to teach undergraduate students at the University of Pretoria, Pretoria, South Africa, some of the main issues regarding closed-loop system identification, is discussed. In this experiment, a plant is identified both from open-loop and closed-loop data. The model obtained from the open-loop data is used as reference to evaluate a closed-loop system identification approach. A motivation for closed-loop system identification and a laboratory experiment in this field is given. The experiment is outlined, each step is discussed, and the experiment is evaluated. This experiment shows that closed-loop system identification can be taught in an uncomplicated manner. Index Terms--Closed-loop identification, education, experimental data, modeling, process control.

This paper describes how HIV/AIDS education is being introduced into the curriculum of the Department of Electrical, Electronic, and Computer Engineering at the University of Pretoria, Pretoria, South Africa. Third- and fourth-year students were provided with an HIV/AIDS Educational CD developed at the university. Their knowledge of the subject was tested via two quizzes--one written before they were exposed to the material on the CD and one after. In addition, a mathematical HIV/AIDS model is being incorporated into a third-year control systems course. This model is used to illustrate standard control systems engineering concepts, such as linearization, system stability, feedback, and dynamic compensation. This paper is an example of how topical nonengineering material can effectively be made part of a high-level undergraduate engineering course. Students benefit not only from the topical nature of the subject, but also from an improved understanding of control engineering concepts which can be applied to many different fields. Index Terms--Acquired immune deficiency syndrome (AIDS), control systems engineering, education, human immunodeficiency virus, immune system, modeling.

This paper shows an application of control theory to human immunodeficiency virus (HIV)/AIDS models. Minimum singular value decomposition is applied to HIV/AIDS models to measure the extent to which the different stages in the progression of HIV/AIDS disease are controllable and, consequently, when best to initiate therapy such that the general objectives of therapy are satisfied. Simulations will be used to demonstrate the effect of treatment at various stages. Comparisons will be made between mono-class and combination therapies and between when therapy is initiated at the acute infection, asymptomatic and the advanced stages. Index Terms--Chemotherapy, controllability, HIV, initiate therapy, singular value.

A detailed mathematical modeling framework for the risk of airborne infectious disease transmission in indoor spaces was developed to enable mathematical analysis of experiments conducted at the Airborne Infections Research (AIR) facility, eMalahleni, South Africa. A model was built using this framework to explore possible causes of why an experiment at the AIR facility did not produce expected results. The experiment was conducted at the AIR facility from August 31, 2015 to December 4, 2015, in which the efficacy of upper room germicidal ultraviolet (GUV) irradiation as an environmental control was tested. However, the experiment did not produce the expected outcome of having fewer infections in the test animal room than the control room. The simulation results indicate that dynamic effects, caused by switching the GUV lights, power outages, or introduction of new patients, did not result in the unexpected outcomes. However, a sensitivity analysis highlights that significant uncertainty exists with risk of transmission predictions based on current measurement practices, due to the reliance on large viable literature ranges for parameters. [ABSTRACT FROM AUTHOR]

Index Terms--Case study course, control systems, industrial control. I. SUMMARY This paper describes a graduate-level control course at the University of Pretoria, South Africa, the aim of which is to develop case studies on industrial control applications. Groups of students are given a specific industrial control problem to study, as facilitated by experts from industry. Students study the process via a literature survey by spending time on the plant in question and by interviewing operators and technical personnel. They then formulate the control problem, provide a conceptual solution, quantitatively test their proposed solutions in a simulated environment, and write a case study on the assigned problem. Cases are finally presented to a panel of experts.