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The purpose of this research is to construct and test a model of the organization of microcore technology, a standardized core technology, within the subsistence-settlement system of prehistoric, semi-sedentary hunter-gatherers. The study of technological organization involves investigation of why a society selects particular tool designs, and how it structures the manufacture, use, maintenance and discard of tools and associated debitage across the landscape. The model tested here associates the use of microcore technology with a design for a maintainable and transportable tool assemblage which conserves lithic material, and with a regional distribution focused on residential camps as the locus of microcore manufacture and microblade production and use. The model is tested through a comparative case study of archaeological tools and debitage from microlithic and non-microlithic sites in two upland valleys in the British Columbia Southern Interior Plateau. Research hypotheses and corresponding test implications are evaluated with data and analyses relating to core reduction and tool production stages, to tool use, and to activity area patterning within the sites. Results of hypothesis testing indicate that the model only partially explains the role of this particular standardized core technology in the study areas. Microcore technology is found to be associated with high residential and logistical mobility; a transportable, expediently-used tool assemblage; and the conservation of a specific raw material in one valley. Thus, this research proposes that microcore technology was a standardized technology which was variable in design goals and distribution, even within the same geographically and ethnographically defined region. / Arts, Faculty of / Anthropology, Department of / Graduate

Self-excited chatter is a basic performance limitation in the machining of metals. Self-excited chatter was investigated both experimenttally and theoretically in the present research. An experimental lathe was constructed so as to obtain orthogonal one degree of freedom cutting. An experimental method developed by Brockley and Ko which enables the recording of a phase plane diagram and the force-velocity curve of one cycle of vibration was used. Experiments were carried out on 70-30 lead free brass workpiece disc with a high speed steel tool at surface speeds ranging from 2 in/sec to 20 in/sec. The results revealed that the force-velocity curve was 'loop' shaped. The chatter vibration was quasi-harmonic and the growth and decay of vibration amplitude with variation in surface speed was observed. Frictional quasi-harmonic vibration was observed to occur in the same speed range which suggested the concept that metal-cutting chatter could be friction actuated. The experimental force-velocity curve was employed in a graphical construction of the phase plane representation of the vibration. The constructed phase plane was in close agreement with the experimental recording. / Applied Science, Faculty of / Mechanical Engineering, Department of / Graduate

Existing screening tools are not suitable for the detection of HIV-associated neurocognitive disorders (HAND) in South Africa. Study 1 of the current thesis aimed to establish construct validity of a new screening tool, the Cognitive Assessment Tool-Rapid(CAT-Rapid), in a sample of cognitively healthy South African undergraduates (n = 122).Study 2 investigated the tool¡¯s diagnostic validity in a sample of HIV-positive adult South Africans (n = 89). In Study 1 and Study 2, correlational analyses characterizing the associations between CAT-Rapid subtests and analogous standardized neuropsychological tests sought to establish construct validity. In Study 2, ROC curves, and estimates of sensitivity and specificity values, characterized the CAT-Rapid¡¯s diagnostic validity. Results from Study 1 demonstrated adequate construct validity for the CAT-Rapid in the cognitively healthy sample. Results from Study 2 did not demonstrate construct validity of the tool in the clinical sample. Regarding diagnostic properties, at the recommended cut off score ¡Ü 10, the CAT-Rapid did not demonstrate optimal sensitivity and specificity in the detection of HAND. Future research should investigate how the CAT-Rapid compares to paper-and-pencil screening tests that have demonstrated promising results in studies emerging from the global north.

The purpose of this study is to present in narrative form a discussion of the evolution of hand tools employed in woodwork. The purpose is to make this treatment as concise as possible, and at the same time to depict in some detail a comprehensive analysis of the topic under consideration.

Previous research has shown that when observers hold a tool, they experience action-oriented visual biases in the area around this tool that are similar to visual biases that exist around the hands. Some researchers have theorized this effect is due to the tool being incorporated into the body schema following active tool use, while others argue that this effect may simply be due to the tool’s visual salience. The goal of the present study was to test these competing explanations of near-tool visual biases. In the first experiment, participants completed a target detection task under one of three conditions: 1) while holding a small rake next to one side of a monitor, preceded by an active object retrieval task; 2) while holding a rake next to a monitor, preceded by a passive looking task; or 3) with the rake placed next to a monitor by a researcher, preceded by a passive looking task. Participants detected targets near the rake faster than targets far from the rake in the first two conditions, but no target detection facilitation was seen in the third condition. Participants in Experiment 2 held a small rake next to a monitor after an active object retrieval task, but a paper shield blocked the tool from view, eliminating its visual salience. While the pattern of near-tool target detection facilitation did not significantly differ between shielded and unshielded conditions, the shield did reduce the magnitude of the near-tool effect. Taken together, these results suggest that near-tool effects cannot be driven by the visual presence of a tool alone, but they also indicate that a period of active use may not be necessary to introduce visual biases near tools.

A dissertation submitted in fulfillment of the requirements for the degree of Masters in Clinical Psychology in the Department of Psychology University of Zululand, South Africa, 2011. / The study is aimed at introducing Philophonetics self help tools as an intervention strategy to deal with the unacceptable behaviour of learners in school. The researcher used a total number of ten (10) participants who were between the ages of sixteen (16) to twenty two (22) who are high school learners. Six (6) of the participants were females and four (4) were males. Six of the participants who participated in the study were grade eleven (11) learners and four (4) were grade twelve (12) learners. The participants were chosen from the detention list at their school, the participants were the most frequently appearing learners on the detention list. The findings of the study illustrate that detention was not an answer towards dealing with unacceptable behaviour in learners. Philophonetics self help tools were given to the learners and the participants reported that philophonetics self help tools were effective and has assisted them in changing their behaviour not only at school, but in their personal life as well. Out of ten participants only one participant reported that he was not sure whether or not he will be on detention again. Nine out ten reported that after receiving the self help tools, they were not going to be detained again. / The NRF/CUPP

A thesis submitted in fulfilment of the requirements for the degree of Masters in Communication Science at the University of Zululand, South Africa, 2013. / The purpose of this study was to investigate the effectiveness of the extranet as a communication tool in higher education institutions. The study used the case study of myUnisa - an extranet used at the University of South Africa. This was a mixed-methods research and had applied the quantitative and qualitative methods. This was a multistage study which went through two stages. In the first stage the researcher utilised the questionnaire to collect data from the students. Initially, the questionnaire was intended to be self-administered to allow students to complete them on their own, but difficulties to meet some of the sampled students on one-to-one encounter alternatively led to telephonic interviews on which the role of the researcher was to interview, and to tick and write down the responses of the respondents. Four hundred students were sampled using the online randomizer programme available on the internet. Statistical package for social science (SPSS) version 18 was used to analyse qualitative data. In the qualitative phase, in-depth interviews with two key staff members from each of the department sampled were held and an analysis was done using thematic categorization. The study found that myUnisa is used by different UNISA departments and students for communications. However, although many students and staff members considered myUnisa useful, not all regarded it as effective. In-depth interviews with lecturers showed that myUnisa is both a useful and an effective online communication channel for engaging into communications with the students. An analysis of the responses led to the development of an extranet model for implementation in higher education institution. A number of recommendations were made and suggestions for future research considerations were also given.