How can cooperative learning be developed to enhance the teaching of biology at secondary school level?
- Authors: Pillay, Paramasivan
- Date: 2001
- Subjects: Biology -- Study and teaching (Secondary) Group work in education Group work in education -- Evaluation
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:1557 , http://hdl.handle.net/10962/d1003439
- Description: This research was undertaken by a group of practising teachers as a collaborative effort to develop a cooperative approach to the teaching of Biology at Secondary School level. The research focussed on Grade 10 learners at three different schools over a period of one full academic school-year. During this time, four complete cycles within an action research framework were completed and reflected upon. Learners were then surveyed by means of a questionnaire and follow-up interviews. The reflective sessions, together with the responses from the questionnaire and interviews, provided a wealth of information with regard to the development of a cooperative approach to teaching. The cooperative classroom is vastly different from the traditional one. Here, new roles are assumed by both teacher and learner. Learners are largely expected to take charge of their learning experience in the classroom. The teacher, while still responsible for facilitating this learning experience, delegates authority to the learners. It was the experience of the group that the relationship between teacher and learner, as well as between learner and learner, vastly improved in the cooperative class where the participants were more relaxed. Over time, learners became more accountable in terms of their work and learning. Learners’ self-esteem and self-confidence grew, and the majority of learners indicated that their understanding of the work improved. Furthermore, the cooperative structure encouraged and developed self-discipline in the learners. In the early stages of this research, the group did find certain behaviour to be inhibiting: excessive noise, laziness, too much tomfoolery, and absenteeism. These problems were easily addressed within the action research framework, and were nearly non-existent by the end of the research. The group also found that: (i) cooperative lessons required more time than traditional lessons, often at the expense (justifiably) of the syllabus, and that: (ii) cooperative lessons played a major role in reactivating learner interest towards the learning process both in and outside the classroom.
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- Date Issued: 2001
Ichthyofaunal characteristics of a typical temporarily open/closed estuary on the southeast coast of South Africa
- Authors: Cowley, Paul D , Heemstra, Phillip C
- Date: 2001
- Subjects: Estuarine fishes -- Ecology -- Indian Ocean , Estuarine ecology -- South Africa , Fish communities -- South Africa , Fish communities -- Indian Ocean
- Language: English
- Type: Text
- Identifier: vital:15021 , http://hdl.handle.net/10962/d1019862 , ISSN 0073-4381 , Ichthyological Bulletin J.L.B. Smith Institute of Ichthyology; No. 71
- Description: The present study was undertaken to describe the species composition, size composition and distribution of the fish fauna associated with the temporarily open/closed East Kleinemonde Estuary on the southeast coast of South Africa. Data collected on the estuary mouth condition from March 1993 to August 1997 indicated that this system was predominantly closed, while open mouth conditions were unseasonal and prevailed for only a short duration following periods of high rainfall. Fishes were sampled throughout the estuary between April 1993 and January 1997 using seine and gill nets. A total of 30 species belonging to 17 families were recorded, including the critically endangered estuarine pipefish Syngnathus watermeyeri. Besides the estuarine pipefish, an additional five species capable of completing their life cycle within the estuary were recorded. The ichthyofaunal community was dominated by 18 marine-spawning species with varying degrees of dependence on estuaries as nursery areas. The marine species that are not dependent on estuaries as nursery areas were represented by three species, while the euryhaline freshwater species, obligate catadromous species and facultative catadromous species were each represented by one species. The dominant members of the estuarine-spawning group were well represented by all post-larval life-history stages, whereas the mean size of each marine-spawning species indicated that juvenile size classes dominated this group. Classification and ordination of both the small- and large-mesh seine net fish assemblages revealed a high degree of similarity throughout the estuary, with the exception of a distinct grouping associated with sandy substrata in the lower reaches of the system. Catch per unit effort (CPUE) data provided evidence of spatial segregation by several species as well as within some families (e.g. Gobiidae). , Rhodes University Libraries (Digitisation)
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- Date Issued: 2001
Ichthyofaunal community structures in different types of Eastern Cape estuaries
- Authors: Vorwerk, Paul D
- Date: 2001
- Subjects: Estuarine fishes -- South Africa -- Eastern Cape , Estuarine fishes -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5377 , http://hdl.handle.net/10962/d1016241
- Description: This investigation had three major objectives; firstly to document the estuarine fishes from several poorly studied Eastern Cape estuaries, secondly, to identify similarities and differences in the fish communities from permanently open and intermittently open estuaries, and thirdly, to establish which physico-chemical or environmental variables are responsible for the structuring of these communities. The study area incorporated 10 estuaries along a 70 km long stretch of the Eastern Cape coastline between the towns of Seafield (33° 32' 42" S, 27° 03' 05" E) in the south-east and Hamburg (33° 16' 45" S, 27° 29' 50" E) in the north-west. The systems investigated included two permanently open estuaries and eight intermittently open systems of varying sizes. Overall fish abundance and species richness in the study area revealed no significant seasonal variation. A contrast between open and closed estuaries was evident in the dominance of species from different estuarine dependence categories. Open estuaries comprised mainly category Ib, lla and IIb species, with a high proportion of category IV species. Closed estuaries were dominated by category IIa species, with few category IV species represented. Clear longitudinal trends in relative abundance were demonstrated for individual species. Margalefs species richness index for seine net catches, and a combination of the seine and gill net data, were significantly correlated with catchment size, mean annual runoff, estuarine area and linear length. Fish assemblages in the permanently open and intermittently open estuaries were significantly different (p<0.001) when analysed on a community and density basis. Similarly, the communities in large and small intermittently open estuaries differed significantly on a community (p=0.01) and density basis (p<0.001). These differences where caused by changes in abundance of the dominant estuarine resident and marine migrant species. The environmental variable that was dominant in accounting for these differences was the estuary mouth status. Estuarine resident species had smaller overall body lengths when compared with the marine migrant species. In addition, the estuarine resident species had smaller modal size classes in the closed estuaries when compared with the open estuaries. These differences may be linked to the foraging strategies of the species, as well as food availability and different levels of predation in the different estuary types. The marine migrant species did not show any trends in this respect although the closed systems had the largest individuals for all four dominant marine species. This finding may be linked to the inability of these species to breed in closed estuaries, thus channelling reproductive energy resources into somatic growth. In addition, prolonged periods of mouth closure prevent the emigration of large individuals back to the sea. Otter trawling was conducted in fiye estuaries and captured mostly demersal species. The otter trawl data confirmed the seine net community analysis, with significantly different communities identified in the permanently open and intermittently open estuaries (p=0.02), as well as in the small and large intermittently open estuaries (p=0.03). The environmental variables responsible for these community differences were mouth status and variables associated with estuarine size. The identification of estuary mouth status by this study as the most influential environmental factor is compounded by this "ariable affecting or being indicative of numerous other physico-chemical features. The large differences in the fish communities in different estuary types indicate the importance of each estuary type to various species. This should be taken into account before allowing any form of commercial fishing in these important nursery areas.
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- Date Issued: 2001
Implementation and applications of the distortion operator
- Authors: Bangay, Shaun D
- Date: 2001
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/433382 , vital:72966 , https://doi.org/10.1145/513867.513872
- Description: The distortion operator transforms 2D images in a manner similar to image warping or morphing, allowing source pixels to be mapped to any destination pixel. This operator can be implemented on current hardware, allowing at least one distortion per frame at interactive frame rates. Potential applications are numerous, but those described include re-mapping images for correct projection onto curved screens, correcting camera distortion from multiple sources simultaneously, and allowing constant time dynamic texturing and lighting of a static scene which is independent of geometric complexity.
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- Date Issued: 2001
In the gaze of God : aspects of the spiritual significance of Rublev's holy trinity
- Authors: Snyman, Desiree
- Date: 2001
- Subjects: Prayer , Spirituality
- Language: English
- Type: Thesis , Bachelor , BDiv
- Identifier: vital:1302 , http://hdl.handle.net/10962/d1016261
- Description: An icon is more than an image. It is a "sacramental form of presence" that makes present that which it signifies (Evdokimov 1976: 167). To come before an icon is to come before the presence of God. To gaze at an icon is to pray. Rublev's Holy Trinity icon (see frontispiece) is a theology in colour. Inspired by the story in Genesis 18, the icon depicts the three hypostases of the Trinity sitting around an altar with a chalice placed on top. The Biblical story is an account of the genuine hospitality that Abraham and Sarah shared with three pilgrims. This theme of hospitality is expressed by the three hypostases in the icon who invite the cosmos to share in their love-life. This research project investigates aspects of the spiritual significance that Rublev's icon has on our Christian living. To this end, an interpretation of the icon is offered in chapter two. Chapter three focuses on the relationship among the three hypostases in the icon. This chapter reflects on the meaning that trinitarian pericheresis could have on our spiritual living in the way we develop our relationships and the type of church and socio-political structures we adopt and support. The research project also explores the meaning that Rublev's icon could have for Methodists. The resource that Wesleyan spirituality offers to those who seek a deepened spirituality is the doctrine of Christian perfection. Perfection, in the Wesleyan model, is sought through the means of grace, nurtured through Christian koinonia and evidenced in social transformation. Christian perfection is discussed with reference to Rublev's icon in chapter four. Chapter five summarises aspects of the spirituality of the icon, postulates some implications that the icon has and unravels key issues arising out of this study.
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- Date Issued: 2001
In vitro passage of ibuprofen through synthetic and biological membranes
- Authors: Purdon, Carryn Hamilton
- Date: 2001
- Subjects: Ibuprofen , Diffusion processes
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3786 , http://hdl.handle.net/10962/d1003264 , Ibuprofen , Diffusion processes
- Description: Ibuprofen is a non-steroidal anti-inflammatory drug with three major types of effect: anti-inflammatory, analgesic and antipyretic. Ibuprofen may be administered in a number of different forms via the oral as well as the topical route. Published evidence suggests that topical, unlike oral, non-steroidal anti-inflammatory drugs are associated with few systemic side effects as plasma concentrations are low compared to oral therapy. In some countries it is particularly difficult to obtain human skin for in vitro experimentation and it is therefore important to have alternate biological or synthetic membranes which mimic human skin for diffusion experiments. Synthetic membranes serve as predictive models for topical drug release and in South Africa, shed snake skin is easily obtainable from the many snake parks present in the country. The FDA guidelines were considered when choosing the apparatus to be used in the comparative diffusion study on proprietary ibuprofen-containing topical preparations from three countries and the verification of the usefulness, or otherwise, of shed snake skin as a biological membrane for the assessment of the permeation of ibuprofen. Two diffusion techniques were considered appropriate for the measurement of the amount of ibuprofen released from a topical formulation during in vitro testing. One was the Franz diffusion cell, as modified by Keshary and Chien (88,169) and the other was the European Pharmacopoeia diffusion cell (187). High performance liquid chromatography was used as the analytical technique for the analysis of ibuprofen in aqueous solution using ultraviolet detection at 222 nm. The validated method was applied to the determination of the diffusion of ibuprofen from topical ibuprofen-containing formulations (gels, creams and mousse) through synthetic silicone membrane and shed snake skin biological membrane from four different species. In a study of fifteen topical ibuprofen-containing formulations (gels, creams and mousse) from three countries (South Africa, United Kingdom and France) it was found that there was a trend of products from two countries consistently exhibiting superior diffusion characteristics as well as products from the same two countries consistently exhibiting the lowest diffusion of ibuprofen. Interpretation of the results of these studies demonstrated the importance of employing a combination of statistical analyses and peak integration values when drawing conclusions regarding comparative diffusion characteristics. Shed snake skin has been described as a 'model' membrane, i.e. a membrane which shows similar permeability to human stratum corneum. The results reported here show clearly that, for ibuprofen, the four species of snake produce shed skin with completely different diffusion characteristics when all other conditions are identical. It may well be that there is one particular species of snake which produces shed skin of identical permeability to human stratum corneum, but to describe shed snake skin in general as a model membrane seems incorrect. It is therefore important that if shed snake skin is used as a membrane, the species, skin site and orientation should be reported. The European Pharmacopoeia diffusion apparatus was judged to be the better of the two diffusion techniques assessed for the measurement of the amount of ibuprofen released from a topical formulation during in vitro testing using silicone membranes and for the measurement of the amount of ibuprofen diffusing across the ventral outside orientation of shed skin during in vitro testing, whereas the Franz diffusion apparatus was judged to be better for the measurement of the amount of ibuprofen diffusing across the dorsal outside orientation of shed skin during in vitro testing. However, the choice of this diffusion apparatus must be weighed against the relatively poor reproducibility as compared with the European Pharmacopoeia diffusion apparatus.
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- Date Issued: 2001
Influences of food quality and quantity on the male reproductive organs of a seasonally breeding rodent, the pouched mouse (Saccostomus campestris), from a seasonal but unpredictable environment
- Authors: Tinney, Gregory M , Bernard, Ric T F , White, Rehema M
- Date: 2001
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/447258 , vital:74600 , https://doi.org/10.1080/15627020.2001.11657110
- Description: Reproduction in the pouched mouse (Saccostomus campestris) is inhibited in winter in the field and this seasonality is not controlled by photoperiod alone. The present study examines the hypothesis that reproduction in the pouched mouse is opportunistic (sensu Bronson 1989) and that the winter inhibition of reproduction is controlled by a reduction in either food quantity or quality. Food restriction (70 % of normal daily food intake) for six weeks, under short day conditions, was associated with a significant decrease in body fat index and mass of the accessory glands, testes and epididymides, while a high-fibre diet resulted in a significant reduction in fat index and masses of both the accessory glands and epididymides. A low-fibre/low-protein diet had no significant effect on either fat index or masses of the reproductive organs. Although the three experimental diets resulted in assimilation of significantly less energy than the controls, they did not inhibit spermatogenesis. We conclude that reproduction in the pouched mouse in the Eastern Cape Province is probably opportunistic and that the winter inhibition of reproduction may be controlled by a reduction in available energy which results from a combination of the lower ambient temperatures of winter and reduced food quantity and/or quality.
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- Date Issued: 2001
Interaction of serotonin and melatonin with sodium, potassium, calcium, lithium and aluminium
- Authors: Lack, Barbara , Daya, Santy , Nyokong, Tebello
- Date: 2001
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/291553 , vital:56886 , xlink:href="https://doi.org/10.1034/j.1600-079x.2001.310202.x"
- Description: In the present study, we investigated the ability of serotonin and melatonin to bind metals that occur naturally in the brain. An electrochemical technique called adsorptive cathodic stripping voltammetry (AdCSV) was employed to study the metal–serotonin or metal–melatonin interactions. The results show that both serotonin and melatonin form stable complexes with lithium and potassium, with serotonin favouring lithium over potassium, and melatonin favouring potassium over lithium. Coordination between either serotonin or melatonin and calcium was not favoured. The stability of the complexes formed between serotonin and the metals decreased with the metals as follows: Li+>K+>Al3+>Na+>Ca2+. The trend for melatonin–metal complexes was K+>Li+>Na+>Al3+>Ca2+. The binding and stable complex formation between both ligands, serotonin and melatonin with lithium, potassium and sodium is of biological importance. The binding of serotonin to lithium could provide an explanation for the therapeutic effects of lithium in depression treatment, whereas the binding of aluminium by melatonin could provide insight into the role of this element in the aetiology of Alzheimer's disease.
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- Date Issued: 2001
Investigations to determine the long-term sustainable yield of the Karoo aquifer and the sustained availability of groundwater for small-scale irrigation projects, in Dendera area, Kwekwe District - Zimbabwe
- Authors: Njanike, Joseph Tendayi
- Date: 2001
- Subjects: Groundwater , Irrigation -- Equipement and supplies , Irrigation -- Kwekwe (Zimbabwe)
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5093 , http://hdl.handle.net/10962/d1020853
- Description: In this thesis the long-term sustainable yield of the Karoo sediment aquifer unit occurring in Dendera area of Kwekwe District is investigated, with the object of providing quantitative data on the sustained availability of groundwater for small-scale irrigation projects. Archaean Basement Schists and Pre-Cambrian gneissic granites, the Basement Complex rocks, underlie the entire study area. Overlying these are Upper Karoo sediments. Aeolian Kalahari sands unconformably mantle higher interfluves, while redistributed sands occur along valleys of major rivers and streams. The Karoo sediments, which predominantly consist of loosely cemented, fine- to medium-grained sandstone alternating with red siltstone and mudstone, constitute the main aquifer. The thickness of the Karoo sediment unit ranges from 30m to 80m. The hydraulic parameters of the Karoo sediment aquifer were characterised in the field by constant discharge pumping tests and slug tests. Pumping tests indicated unconfined conditions and thus the Neuman's method of analysis has been used. Transmissivities from pumping tests are within the range 4.7 m²/d to 13.6 m²/d with an average of 8.9m²/d. The low transmissivities seem to be a major limiting factor in the exploitation of the groundwater resources. Thus the sustainable borehole yields tend to be small, mean values ranging from 33 m²/d to 253 m²/d. Specific yield could not be determined from the pumping tests due to the lack of observation boreholes. Low chemical concentrations render the water suitable for irrigation of all crops, while neither total nor any individual concentrations present health hazards to human or livestock. An average recharge value of 47.7 mm/y was inferred from water table fluctuation method. Chloride mass balance technique in the same area indicates recharge value in the order of 67.4 mm/y. Because the chloride mass balance gives a long-term mean annual recharge, the recharge figure of 67.4 mm/y was adopted for the study area. Based on the abstractable proportion of recharge, the sustainably exploitable volume of groundwater of the order of 2.68 x 10⁷ m³/y was established. This volume is more than 100 times the estimated current demand for groundwater (1.35 x 10⁵ m³/d), implying that there are large volumes of surplus water, which can be utilised for irrigation.
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- Date Issued: 2001
It's the training that did it: a primer for media trainers to assess their impact
- Authors: Berger, Guy
- Date: 2001
- Language: English
- Type: Text
- Identifier: vital:536 , http://hdl.handle.net/10962/d1008555
- Description: To improve journalism, media trainers need information about what’s working and what needs work in the courses they deliver. This means assessing the impact of this training – as it affects attitudes, information, skills and results in the workplace. To isolate the role that training plays, research and evaluation have to take place long before a course begins and continue till long after. This booklet explains the complexities involved, and it provides the tools for trainers to devise usable strategies to assess the impact of their work. The author critically draws from extensive management training literature, and produces a revised theory that he applies to the unique enterprise of journalism training and its assessment.
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- Date Issued: 2001
Khoisan revivalism: the claims of Africa’s first indigenous peoples: racism and the media
- Authors: Garman, Anthea
- Date: 2001
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/${Handle} , vital:40222 , https://hdl.handle.net/10520/EJC144705
- Description: An unexpected development in post-apartheid South Africa is the revivalism of Khoisan identity, the truly indigenous of the country whose blood flows through many who now know themselves by different names.
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- Date Issued: 2001
KwaZakele: the politics of transition in South Africa: an Eastern Cape case study
- Authors: Cherry, Janet Mary
- Date: 2001
- Subjects: South Africa -- Transition to democracy Democracy -- South Africa -- Eastern Cape Eastern Cape (South Africa) -- Politics and government Port Elizabeth region (South Africa) -- Political aspects
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:2766 , http://hdl.handle.net/10962/d1002976
- Description: This thesis examines the transition to democracy in South Africa through the use of case study methodology. The nature of political participation and the form of democracy to emerge at the end of the transition process are the central subjects of inquiry. They are examined through an in-depth study of the African community of Kwazakele, a township in the Nelson Mandela metropolitan area in the Eastern Cape province of South Africa. The study covers the period from 1993 to 2000, and uses as a primary data source five surveys conducted among residents of Kwazakele during that period. The emphasis of the study lies on the experience of political participation of ‘ordinary people’ – in particular, the African urban working-class in South Africa who make up the core support base for the governing African National Congress. The primary findings of the thesis are as follows: * Representative democracy has been successfully consolidated in the community under study. * Levels of political participation by urban Africans in the Eastern Cape are consistently high, both in formal political institutions (primarily elections) and in institutions of civil society. * As politics has normalised at the end of the transition period, forms of direct democratic participation have declined. * Despite the structural constraints on development, there is still potential for a high level of participation by citizens in effecting change at local level. * Drawing on the experience of ordinary people in structures of direct democracy, this level of participation can result in a deeper and stronger form of democracy than exists in many established representative democracies.
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- Date Issued: 2001
Laboratory and occupation-simulating isokinetic and psychophysical responses of military personnel
- Authors: James, Jonathan Peter
- Date: 2001
- Subjects: Isokinetic exercise , Soldiers -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5126 , http://hdl.handle.net/10962/d1005204 , Isokinetic exercise , Soldiers -- South Africa
- Description: The present study assessed the isokinetic responses of male military personnel(N=42). The study aimed to evaluate the strength capabilities of South African infantrymen and establish benchmark data on a population not previously tested. “Work-simulation” packages have not been widely exploited and this study further aimed to approximate how effectively occupation simulating tasks could identify the capabilities of soldiers. Testing was carried out using a CYBEX 6000 isokinetic dynamometer and involved six laboratory tests (LTs) and four occupation-simulating tests (OSTs). Subjects were required to complete two testing sessions with the order of tests randomized. The LTs consisted of ankle, elbow, hip, knee, shoulder and trunk. In the OSTs, gripping, valve-tightening, wrench-turning and pulling/pushing responses were collected. Slow, medium and fast test speeds were used for each bout. Cardiac responses were measured using heart rate monitoring and perceptual measures assessed using Borg’s (1971) RPE scale. The results of the testing showed significant differences in agonist and antagonist responses at all three testing speeds, the only exception being slow speed trunk values (peak torque). Upper- to lower-extremity ratios highlighted a possible weakness in the elbow flexors group, while correlations between LTs and OSTs highlighted the specificity of strength principle, as poor relationships were observed.
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- Date Issued: 2001
Language policy, symbolic power and the democratic responsibility of the post-apartheid university
- Authors: Alexander, Neville
- Date: 2001
- Subjects: Academic Freedom -- South Africa Universities and colleges -- South Africa Equality Liberty Education and state -- South Africa Education, Higher -- South Africa
- Language: English
- Type: text
- Identifier: http://hdl.handle.net/10962/696 , vital:19982
- Description: Recent articles by John Higgins (1999) and André du Toit (2000), both of the University of Cape Town and a forthcoming article by Roger Southall and Julian Cobbing have contextualised the discussion of this perennial question in both time and place. Du Toit, in particular, has put the cat among the pigeons by querying the relevance in the era of globalisation and the corporatisation of institutions of higher learning, of the classic liberal interpretation of the T.B. Davie formula deriving from the 1950s, i.e., the freedom of "the university" to decide whom to teach, what to teach, how to teach and who should teach. The gist of his argument is that the danger no longer comes from outside the walls of the university, in the guise of the racist apartheid state, for instance. Instead, the threat comes from inside the institutions themselves as the result of the so-called managerial revolution, which is a manifestation of the shift of power from the collegium academicum to the administrative officials, since the curricular and pedagogical, i.e., academic, freedom of the lecturing and research staff is thereby put at risk. He maintains that the manner in which Higgins and others have addressed the question is anachronistic in that the political terrain and the institutional dynamics in which universities operate in post-apartheid South Africa are light years removed from the apartheid university. At the very least, one-quarter of the composite formula, that which refers to "whom to teach" has been rendered irrelevant, since there is no longer any barrier to access to tertiary education, besides those that operate in any "normal" capitalist democracy.
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- Date Issued: 2001
Living in Grahamstown East/Rini: a social indicators report
- Authors: Moller, Valerie , Manona, Cecil Wele , Van Hees, C , Pillay, E , Tobi, A
- Date: 2001
- Language: English
- Type: Book , text
- Identifier: vital:540 , http://hdl.handle.net/10962/d1010769
- Description: [From the preface]: The ‘Living in Grahamstown East/Rini’ project takes its title from a series of reports on social indicators initiated by Statistics South Africa. The popular series aims to communicate to ordinary people the statistics on living conditions in various parts of the country. The first two booklets in the series, Living in South Africa and Living in Gauteng, were based on survey data for South Africa and Gauteng Province (CSS: 1996; 1997). In similar vein, this booklet presents statistics on living conditions in Grahamstown East/Rini for ready reference by community organisations, local planning and policy-makers, scholars, and the general public. [From the introduction]: This report is intended to serve the needs of information users. The source of information is a representative sample survey of 862 Grahamstown East/Rini households conducted in May 1999. The report serves as a reference work for municipal planners and policymakers, community organisations, and interested citizens. It is hoped that the reported social indicators will be useful for drawing up business plans for community development projects. The information in this report is mainly factual. It is based on self-reports collected from households in Grahamstown East/Rini. In time, the facts contained in this report will date. They will then gain historical value for scholars with an interest in learning "how things were" to compare the situation in Grahamstown East/Rini in 1999 with later developments and changes in living conditions and lifestyles , This was edited by Valerie Møller, with contributions by Cecil W. Manona, Charlotte van Hees, Edmund Pillay and Andile Tobi , Digitised by Rhodes University Library on behalf of the Institute of Social and Economic Research (ISER)
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- Date Issued: 2001
Magnitudes and temporal sequencing of load kinematics and kinetics for single-handed pulls
- Authors: MacKinnon, S N
- Date: 2001
- Language: English
- Type: Article
- Identifier: vital:6747 , http://hdl.handle.net/10962/d1009327
- Description: This paper provides data regarding kinematics and kinetics during single-handed, submaximal pulls about various locations in the frontal plane for three loads (6, 12 and 18% lean body mass). Pulls were executed at two relative heights (elbow and eye) through two parasagittal planes also relative to subject morphology. Results indicate that in most cases load and pull location influence the occurrence of measured kinetic variables within a pull cycle but have little effect on the magnitude of these values. Findings from this study suggest that analyses of kinematic and kinetic movement histories may be required for a better understanding of the mechanical loading profiles upon operators engaged in such manual materials handling activities.
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- Date Issued: 2001
Managing regrowth of an indigenous savanna tree species (Terminalia sericea) for fuelwood: The influence of stump dimensions and post-harvest coppice pruning
- Authors: Shackleton, Charlie M
- Date: 2001
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/181672 , vital:43757 , xlink:href="https://doi.org/10.1016/S0961-9534(00)00086-6"
- Description: Most African savannas are subjected to harvesting of wood, especially for fuelwood, charcoal and construction timber. A key attribute of the resilience and productivity of savannas is the ability of damaged trees to regrow from the remaining stump. Survival of the cut stem and growth rate of the resultant coppice shoots is influenced by several factors, including size of the tree, cutting height and the root/shoot ratio after felling. Some of these can be manipulated to maximise subsequent regrowth, but this is little understood for most African savanna species. This study investigated the influence of original tree size, height of cut and post-harvest pruning on regrowth of Terminalia sericea. Regrowth was monitored as the number of coppice shoots, the mean coppice shoot length and the cumulative coppice shoot length per cut stump over four growing seasons. There was a positive relationship between cutting height and number of coppice shoots, but height of cut did not significantly affect mean or cumulative coppice shoot length. Larger stems produced more coppice and had greater mean and cumulative coppice shoot lengths than smaller stems. Post-harvest pruning increased the mean shoot length, but not the cumulative shoot length. After four growing seasons mean shoot length for the single shoot pruning treatment (one shoot left) was 54% greater than for the no prune treatment, whilst the double shoot pruning (two shoots left) was 40% greater. Extrapolated harvest intervals for fuelwood poles were 3–4 years for large stems, 4–5 years for medium-sized stems, and 4–9 years for small stems.
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- Date Issued: 2001
Measuring the value of the arts to society: the importance of the value of externalities for lower income and education groups in South Africa
- Authors: Snowball, Jeanette D , Antrobus, Geoffrey G
- Date: 2001
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/143134 , vital:38204 , https://doi.org/10.1111/j.1813-6982.2001.tb00034.x
- Description: Governments in many countries have cut their support of the arts on the grounds that it is the pleasure of the higher income, well educated members of society that they are sponsoring. In the 1980's government support of the arts, even in developed countries, fell by 30 per cent (Throsby 1994). While it is true that many studies have found that arts attenders represent the educated, prosperous minority of society (Morrison and West, 1986; Dobson and West, 1990; Hendon 1990), this paper argues that if the social as well as the more traditional economic measures of the value of the arts are considered, it can be shown that many of the positive externalties provided by the arts accrue to lower income and education groups.
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- Date Issued: 2001
Mentoring and prospects for teacher development - a South African perspective
- Authors: Probyn, Margie , Van der Mescht, Hennie
- Date: 2001
- Language: English
- Type: Conference paper
- Identifier: vital:6090 , http://hdl.handle.net/10962/d1009744
- Description: School-based mentoring has developed in response to a number of factors pertaining to the pre-service education of student teachers and the in-service professional development of experienced teachers. Traditionally teacher education has consisted of university-based theory with school-based practice, based on an understanding of professional learning as ‘theory into practice’. One of the problems with this model is that theory may come to seem too remote from practice, and that practice appears untheorised by remaining implicit and unproblematised. The one-year teachers’ diploma course offered by the Rhodes University Education Department incorporates a ten-week teaching practice slot. This protracted period has been useful in allowing frequent and consistent contact between university tutors and student teachers, and between mentor teachers and student teachers. Where the system has not been strong is in enabling meaningful collaboration among all three parties. A pilot school-based mentoring programme was thus implemented in 1999, involving English First and Second Language student teachers, the two university tutors and seven mentor teachers. Ongoing evaluative research revealed that the programme was welcomed by all, and that the student teachers in particular gained much in the way of learning to be critically reflexive in a non-threatening environment. However, the research also uncovered areas that need to be developed. Student teachers, for example, need guidance in terms of learning how to talk about teaching; mentor teachers need to develop the confidence and expertise required to open up their practice in a critically constructive context. On the strength of the programme’s success, the Education Department has extended school-based mentoring to all HDE students, and is exploring ways of setting up courses through which other educators (such as EDOs) may receive training in pre- and in-service teacher mentoring.
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- Date Issued: 2001
Monitoring a diagnosis for control of an intelligent machining process
- Authors: Van Niekerk, Theo
- Date: 2001
- Subjects: Expert systems (Computer science) -- Industrial applications , System design
- Language: English
- Type: Thesis , Doctoral , DTech (Engineering)
- Identifier: vital:10814 , http://hdl.handle.net/10948/70 , Expert systems (Computer science) -- Industrial applications , System design
- Description: A multi-level modular control scheme to realize integrated process monitoring, diagnosis and control for intelligent machining is proposed and implemented. PC-based hardware architecture to manipulate machining process cutting parameters, using a PMAC interface card as well as sensing processes performance parameters through sampling, and processing by means of DSP interface cards is presented. Controller hardware, to interface the PC-based PMAC interface card to a machining process for the direct control of speed, feed and depth of cut, is described. Sensors to directly measure on-line process performance parameters, including cutting forces, cutting sound, tool-workpiece vibration, cutting temperature and spindle current are described. The indirect measurement of performance parameter surface roughness and tool wear monitoring, through the use of NF sensor fusion modeling, is described and verified. An object based software architecture, with corresponding user interfaces (using Microsoft Visual C++ Foundation Classes and implemented C++ classes for sending motion control commands to the PMAC and receiving processed on-line sensor data from the DSP) is explained. The software structure indicates all the components necessary for integrating the monitoring, diagnosis and control scheme. C-based software code executed on the DSP for real-time sampling, filtering and FFT processing of sensor signals, is explained. Making use of experimental data and regression analysis, analytical relationships between cutting parameters (independent) and each of the performance parameters (dependent) are obtained and used to simulate the machining process. A fuzzy relation that contains values determined from statistical data (indicating the strength of connection between the independent and dependent variables) is proposed. The fuzzy relation forms the basis of a diagnostic scheme that is able to intelligently determine which independent variable to change when a machining performance parameter exceeds control limits. The intelligent diagnosis scheme is extensively tested using the machining process simulation.
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- Date Issued: 2001