Game ranching in South Africa: its contribution to the economy, to conservation and to biodiversity

Presented at the 9th international wildlife ranching symposium: wildlife - the key to prosperity for rural communities, held on 12-16 September 2016 at Hotel Safari & the Safari Court, Windhoek, Namibia.Wildlife ranching in South Africa is a relatively young industry which has grown at unforeseen rates to an industry bigger than the dairy or the sugar industries in this country. Its history, development, the contribution, as a sustainable form of agriculture, made to the South African economy, decent job creation, food security and to conservation and biodiversity is discussed. Future possible contributions, as future goals of Wildlife Ranching South Africa, are also enunciated

Ilona: An advanced CAI Tutorial System for the Fundamentals of Logic

An advanced tutorial system for teaching the fundamentals of logic has been developed to run on UNIX work stations and commonly available micro-computers. An important part of this tutorial is the intelligent problem solving environment which allows students to practise wiriting logical sentences in mathematical notation. A natural language system for intelligent logic narrative analysis (ILONA) allows students to type in their own logical sentences in plain English and then have the computer check their working when they write these in mathematical form. ILONA is an intelligent tutoring system which allows students a great deal of initiative in problem solving and provides a degree of flexibility in answer evaluation not found in traditional CAI systems. The concepts and structures used in the development of ILONA are easily transferable to other domains

A computer-controlled tracking system

A computer-controlled tracking system has been designed and constructed for the two metre antenna of the 22 GHz radio telescope at Rhodes University. The control system has been tested and its step response has been analysed with a view to response time optimization. Computer programs for tracking the sun and the moon have been written. Initial results of tracking the sun have revealed linearity and temperature stability problems. These problems have been investigated and suggestions have been made as to how they might be remove

An intelligent computer-based tutor for elementary mechanics problems

ALBERT, an intelligent problem-solving monitor and coach, has been developed to assist students solving problems in one-dimensional kinematics. Students may type in kinematics problems directly from their textbooks. ALBERT understands the problems, knows how to solve them, and can teach students how to solve them. The program is implemented in the TUTOR language and runs on the Control Data mainframe PLATO system. A natural language interface was designed to understand kinematics problems stated in textbook English. The interface is based on a pattern recognition system which is intended to parallel a cognitive model of language processing. The natural language system has understood over 60 problems taken directly from elementary Physics textbooks. Two problem-solving routines are included in ALBERT. One is goal-directed and solves the problems using the standard kinematic equations. The other uses the definition of acceleration and the relationship between displacement and average velocity to solve the problems. It employs a forward-directed problem-solving strategy. The natural language interface and both the problem-solvers are fast and completely adequate for the task. The tutorial dialogue system uses a modified version of the natural language interface which operates in a two-tier fashion. First an attempt is made to understand the input with the pattern recognition system, and if that fails, a keyword matching system is invoked. The result has been a fairly robust language interface. The tutorial is driven by a tutorial management system (embodying a tutorial model) and a context model. The context model consists of a student model, a tutorial status model and a dynamic dialogue model. ALBERT permits a mixed initiative dialogue in the discussion of a problem. The system has been tested by Physics students in more than 80 problemsolving sessions and the results have been good. The response of the students has been very favourabl

The regulation of the use of cannibis in the workplace

This treatise considers the implications of the judgment in Minister of Justice and Constitutional Development v Prince (2018) ZACC 30 in the workplace. It includes a critical study of cases prior and post the judgment and identifies the gaps within those judgments. It will consider various legislation pertaining to the topic and the critical differences when it comes to testing for intoxication of alcohol versus cannabis. To conclude, it will consider the challenges of having a zero-tolerance policy in the workplace and provide recommendations to employer’s substance abuse policies specifically relating to the use of cannabis and its effects within the workplace

A method for the assessment of blackfly (Diptera: Simuliidae) attraction to and engorgement on sheep in South Africa

A suspended-net technique was used to capture blackflies attracted to and engorging on Dorper and Merino sheep on irrigated pastures. Two bait animals of each breed were restrained individually in wire-mesh enclosures located within four larger pens, each containing nine more animals of the same breed. Nets were suspended partly over the restrained animals and blackflies were collected at the end of 2-hour or longer periods. Mean numbers of blackflies captured in association with Merino (73,3/h) and Dorper sheep (89, 1 /h) did not differ significantly. Numbers of captured blackflies correlated (rho = 0,8361) with levels of irritation shown by sheep. Engorgement on Merinos was significantly (p = 0,009) higher than on Dorpers. Percentage engorgement was low, mostly below 10% on Merinos and below 5% on Dorpers. When high wind speeds and high saturation deficits (associated with temperatures in the mid-thirties) occurred, the success of capture was impaired. The technique is useful for quantifying the abundance of irritating blackflies in the immediate proximity of smallstock under experimental conditions.The articles have been scanned in colour with a HP Scanjet 5590; 600dpi. Adobe Acrobat XI Pro was used to OCR the text and also for the merging and conversion to the final presentation PDF-format.Hoechst Ag-Vet (Pty) Ltd.mn201

Mechanistisches Verständnis der katalytischen CO2-Reduktion mittels in situ IR-Spektroskopie, Spektroelektrochemie und Dichte-Funktional-Theorie

In dieser Arbeit wird die homogen-katalytische CO2-Reduktion thematisiert. Es wurden ein Mangan-/Eisen-Katalysator untersucht, die photokatalytisch und elektrokatalytisch aktiv sind. In-situ-IR-Spektroskopie ermöglichte die Untersuchung der photokatalytischen Reduktion mit dem Mangan-Katalysator. Beide Katalysatoren wurden mit der IR-Spektroelektrochemie betrachtet. Es konnte die CO2-Reduktion mechanistisch betrachtet werden. Quantenchemische Rechnungen haben die Aufklärung der Mechanismen ermöglicht. CO wurde in beiden Reaktionen als Produkt nachgewiesen. Es wurden Intermediate identifiziert.The focus of this work is on the homogeneous catalytic CO2 reduction. A manganese/iron catalyst were investigated. Both catalystsshow activity in regard to the photocatalytic/electrocatalytic CO2 reduction. With in situ IR-spectroscopy the photocatalysis of the manganese catalyst was studied. Both catalysts were investigated with IR-spectroelectrochemistry. Mechanistic studies of the reduction process were feasible. With quantum chemical computations a description of the mechanism was possible. CO was proven to be the product of the CO2-reduction in both cases. Intermediates were identified