The effects of salinity and inundation on salt marsh plants in the context of climate change
- Authors: Tabot, Pascal Tabi
- Date: 2012
- Subjects: Salt marsh plants -- Climatic factors , Plant ecophysiology
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:10637 , http://hdl.handle.net/10948/d1019919
- Description: Ecophysiology studies are needed to predict plant responses in relation to climate change. Variations in salinity and inundation are expected to influence the survival and distribution of salt marsh. The following species were chosen to study as they occur in most South African salt marshes and are representative of different tidal ranges; namely Triglochin buchenaui (lower intertidal), Bassia diffusa (upper intertidal succulent) and Limonium linifolium (upper intertidal non-succulent). To simulate climate change conditions as predicted for South Africa, a 3 x 5 controlled experiment of three inundation levels (tidal, submerged and drought) and five salinity levels (0, 8, 18, 35, 45 ppt) was conducted for each species. This resulted in 15 treatments per species. Plant responses were measured over a three month period. Triglochin buchenaui showed significant variation in height (7.57 ± 0.5 to 29 ± 1.55 cm, p < 0.005, DF = 55) with optimum growth at 0 ppt under tidal conditions; leaf area increments and relative growth rates which decreased with increasing salinity under all inundation states. There was almost a cessation of growth under submergence which reduces the plant’s regeneration potential under these conditions. Proline accumulation (1.84 ± 0.23 to 3.36 ± 0.38 mg l-1), response of photosynthetic pigments and electrolyte leakage (8.17 ± 0.80 to 38.36 ± 7.42 percent) were fundamental to osmotic and membrane response regulation. Plants survived in all inundation states at salinity up to 45 ppt, but the optimum range was 0 to 18 ppt, and best water state was the tidal condition. Viable rhizomes were produced under drought conditions. Bassia diffusa (Thunb.) Kuntze plants under submergence died within one month, irrespective of the salinity. Optimum growth occurred in plants of the tidal treatment at 18 ppt, and reduced with increased salinity and drought conditions. Plants in the tidal treatments were more succulent than the drought-treated plants. There was reduced leaf mass and high anthocyanin concentrations in drought-treated plants and these effects increased with salinity. Soil and leaf water potential were positively correlated with anthocyanin concentration in leaves and stems, suggesting anthocyanin accumulated in response to drought and could be an adaptation to lower the plant’s water potential under drought conditions. A shift of anthocyanin from leaves to stems was found in drought-treated plants, and this possibly enables the maximization of photosynthesis in leaves, to complement its role in osmotic balance and photo-protection. Growth of Limonium linifolium showed that the plant was tolerant to a wide range of salinity under both tidal and drought conditions, but was susceptible to complete submergence, with high membrane damage even in tidal-treated plants. Plants died within 2 weeks of complete submergence. Results further indicated that L. linifolium tolerates extreme drought by accumulating large quantities of proline and oxalic acid, which consequently lowers its water potential for uptake of soil water of high salinity. Excess salts were excreted through salt glands. This is an important adaptation for a plant that thrives in a highly variable saline habitat Further investigation of submergence effects on upper intertidal species using B. diffusa showed three key stages in the response. A drop in chlorophyll a+b within 6 hours (4.2 ± 0.2 to 2.4 ± 0.3 mg l-1) with a corresponding increase in carotenoid concentration (0.6 ± 0.1 mg l-1) indicated an immediate response to submergence. Oxalic acid concentration was highest on Day 4 (13.6 mM) as opposed to control levels, indicative of its role in submergence tolerance, thus Day 4 may be the peak of positive acclimation. The third phase was marked by a sharp increase in electrolyte leakage to 47.5 ± 2.6 percent on Day 10, from 9.4 ± 1.4 percent on Day 7, with a corresponding decrease in total dissolved solutes between Days 7 and 10. Results suggest that oxalic acid accumulates under submergence possibly as a stabilizing osmolyte. The threshold for tolerance of the species under submergence is 7 days with membrane damage thereafter. Bassia diffusa would not survive prolonged submergence (> 7 days) but could survive submergence of short duration (< 7 days) through continuous underwater photosynthesis, accumulation of osmolytes such as oxalic acid and carotenoid, and maintenance of relative water content and succulence within control levels. When considered together, results showed that the two upper intertidal species were sensitive to waterlogging and would not survive complete submergence, whereas the lower intertidal species could in addition to its natural range, thrive in conditions typical of the upper intertidal range, namely prolonged dry conditions and high sediment salinity. These results have important implications for the future management of salt marshes under predicted climate change conditions. In permanently open South African estuaries, a landward migration of salt marsh will be possible if coastal squeeze is limited and the rate of landward recruitment is on par with sea level rise. In this case salt marsh species would retain their current zonation while shifting inland. Increased sea storms and saltwater intrusion could lead to high salinity concentration in the sediment and significantly reduce growth of salt-sensitive plants. In estuaries that are temporarily open to the sea, reduced freshwater inflow will result in an increase in mouth closure, high water levels, prolonged submergence, and consequently die back of salt marsh vegetation. On the other hand increased abstraction and drought would result in low water levels and high sediment salinity which would decrease growth and survival of salt marsh. This research has provided new knowledge on the ecophysiology of salt marsh plants which can be used to predict the responses of plants to climate change.
- Full Text:
- Date Issued: 2012
- Authors: Tabot, Pascal Tabi
- Date: 2012
- Subjects: Salt marsh plants -- Climatic factors , Plant ecophysiology
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:10637 , http://hdl.handle.net/10948/d1019919
- Description: Ecophysiology studies are needed to predict plant responses in relation to climate change. Variations in salinity and inundation are expected to influence the survival and distribution of salt marsh. The following species were chosen to study as they occur in most South African salt marshes and are representative of different tidal ranges; namely Triglochin buchenaui (lower intertidal), Bassia diffusa (upper intertidal succulent) and Limonium linifolium (upper intertidal non-succulent). To simulate climate change conditions as predicted for South Africa, a 3 x 5 controlled experiment of three inundation levels (tidal, submerged and drought) and five salinity levels (0, 8, 18, 35, 45 ppt) was conducted for each species. This resulted in 15 treatments per species. Plant responses were measured over a three month period. Triglochin buchenaui showed significant variation in height (7.57 ± 0.5 to 29 ± 1.55 cm, p < 0.005, DF = 55) with optimum growth at 0 ppt under tidal conditions; leaf area increments and relative growth rates which decreased with increasing salinity under all inundation states. There was almost a cessation of growth under submergence which reduces the plant’s regeneration potential under these conditions. Proline accumulation (1.84 ± 0.23 to 3.36 ± 0.38 mg l-1), response of photosynthetic pigments and electrolyte leakage (8.17 ± 0.80 to 38.36 ± 7.42 percent) were fundamental to osmotic and membrane response regulation. Plants survived in all inundation states at salinity up to 45 ppt, but the optimum range was 0 to 18 ppt, and best water state was the tidal condition. Viable rhizomes were produced under drought conditions. Bassia diffusa (Thunb.) Kuntze plants under submergence died within one month, irrespective of the salinity. Optimum growth occurred in plants of the tidal treatment at 18 ppt, and reduced with increased salinity and drought conditions. Plants in the tidal treatments were more succulent than the drought-treated plants. There was reduced leaf mass and high anthocyanin concentrations in drought-treated plants and these effects increased with salinity. Soil and leaf water potential were positively correlated with anthocyanin concentration in leaves and stems, suggesting anthocyanin accumulated in response to drought and could be an adaptation to lower the plant’s water potential under drought conditions. A shift of anthocyanin from leaves to stems was found in drought-treated plants, and this possibly enables the maximization of photosynthesis in leaves, to complement its role in osmotic balance and photo-protection. Growth of Limonium linifolium showed that the plant was tolerant to a wide range of salinity under both tidal and drought conditions, but was susceptible to complete submergence, with high membrane damage even in tidal-treated plants. Plants died within 2 weeks of complete submergence. Results further indicated that L. linifolium tolerates extreme drought by accumulating large quantities of proline and oxalic acid, which consequently lowers its water potential for uptake of soil water of high salinity. Excess salts were excreted through salt glands. This is an important adaptation for a plant that thrives in a highly variable saline habitat Further investigation of submergence effects on upper intertidal species using B. diffusa showed three key stages in the response. A drop in chlorophyll a+b within 6 hours (4.2 ± 0.2 to 2.4 ± 0.3 mg l-1) with a corresponding increase in carotenoid concentration (0.6 ± 0.1 mg l-1) indicated an immediate response to submergence. Oxalic acid concentration was highest on Day 4 (13.6 mM) as opposed to control levels, indicative of its role in submergence tolerance, thus Day 4 may be the peak of positive acclimation. The third phase was marked by a sharp increase in electrolyte leakage to 47.5 ± 2.6 percent on Day 10, from 9.4 ± 1.4 percent on Day 7, with a corresponding decrease in total dissolved solutes between Days 7 and 10. Results suggest that oxalic acid accumulates under submergence possibly as a stabilizing osmolyte. The threshold for tolerance of the species under submergence is 7 days with membrane damage thereafter. Bassia diffusa would not survive prolonged submergence (> 7 days) but could survive submergence of short duration (< 7 days) through continuous underwater photosynthesis, accumulation of osmolytes such as oxalic acid and carotenoid, and maintenance of relative water content and succulence within control levels. When considered together, results showed that the two upper intertidal species were sensitive to waterlogging and would not survive complete submergence, whereas the lower intertidal species could in addition to its natural range, thrive in conditions typical of the upper intertidal range, namely prolonged dry conditions and high sediment salinity. These results have important implications for the future management of salt marshes under predicted climate change conditions. In permanently open South African estuaries, a landward migration of salt marsh will be possible if coastal squeeze is limited and the rate of landward recruitment is on par with sea level rise. In this case salt marsh species would retain their current zonation while shifting inland. Increased sea storms and saltwater intrusion could lead to high salinity concentration in the sediment and significantly reduce growth of salt-sensitive plants. In estuaries that are temporarily open to the sea, reduced freshwater inflow will result in an increase in mouth closure, high water levels, prolonged submergence, and consequently die back of salt marsh vegetation. On the other hand increased abstraction and drought would result in low water levels and high sediment salinity which would decrease growth and survival of salt marsh. This research has provided new knowledge on the ecophysiology of salt marsh plants which can be used to predict the responses of plants to climate change.
- Full Text:
- Date Issued: 2012
The evaluation of an instructional framework using the Van Hiele levels for learning and teaching geometry: a study in five rural senior secondary schools
- Alex, Jogymol Kalariparampil
- Authors: Alex, Jogymol Kalariparampil
- Date: 2012
- Subjects: Teaching and learning -- Geometry -- Education (Secondary)
- Language: English
- Type: Thesis , Doctoral , D Ed
- Identifier: vital:18470 , http://hdl.handle.net/11260/d1011278
- Description: The Constitution (1996) of the Republic of South Africa forms the basis for social transformation in our new society. The Constitution (Act 108 of 1996) and the amendments that followed provided a basis for curriculum transformation and development in South Africa. The Department of Education introduced the present curriculum known as the National Curriculum Statement, which is modern and internationally benchmarked, in grade 10 in 2006. It required the learners to do seven subjects in grades 10 to 12 of which mathematics or mathematical literacy was prescribed as compulsory subjects. To attain social transformation, the South African Government attached a great deal of importance to the learning and teaching of mathematics and sciences in the South African schools. This study was undertaken in an effort to improve the understanding of geometry and, consequently, the performance and achievement of senior secondary school learners in geometry. The study was inspired by the van Hiele theory. The study made use of the different levels of the van Hiele theory for the development of an instructional framework for geometry in senior secondary schools. The research was conducted in a previously disadvantaged area in South Africa. Given the setting of this study and the wider application of it, the use of ‘hands-on’ and practical approach to use manipulatives and worksheets to improve the geometric understanding was tried and tested in this study. The assumption was that such experiences would make the learning of geometry more relevant and enjoyable for learners from limited financial and underprivileged circumstances. A quasi-experimental design was chosen. A total of 359 learners from five purposively selected schools in Mthatha district in the Eastern Cape Province participated in this study. Qualitative data through interviews were gathered. The data were analysed using IBM SPSS Version 19 and Microsoft Excel. Findings indicated that there was a notable improvement in the performance of learners who were taught by the application of the van Hiele theory. The results revealed that most of the learners were not ready for the application of deductive principles of geometry in terms of formal proof in senior secondary school geometry. Based on the results, some recommendations are made to enhance the teaching and learning of geometry in senior secondary schools.
- Full Text:
- Date Issued: 2012
- Authors: Alex, Jogymol Kalariparampil
- Date: 2012
- Subjects: Teaching and learning -- Geometry -- Education (Secondary)
- Language: English
- Type: Thesis , Doctoral , D Ed
- Identifier: vital:18470 , http://hdl.handle.net/11260/d1011278
- Description: The Constitution (1996) of the Republic of South Africa forms the basis for social transformation in our new society. The Constitution (Act 108 of 1996) and the amendments that followed provided a basis for curriculum transformation and development in South Africa. The Department of Education introduced the present curriculum known as the National Curriculum Statement, which is modern and internationally benchmarked, in grade 10 in 2006. It required the learners to do seven subjects in grades 10 to 12 of which mathematics or mathematical literacy was prescribed as compulsory subjects. To attain social transformation, the South African Government attached a great deal of importance to the learning and teaching of mathematics and sciences in the South African schools. This study was undertaken in an effort to improve the understanding of geometry and, consequently, the performance and achievement of senior secondary school learners in geometry. The study was inspired by the van Hiele theory. The study made use of the different levels of the van Hiele theory for the development of an instructional framework for geometry in senior secondary schools. The research was conducted in a previously disadvantaged area in South Africa. Given the setting of this study and the wider application of it, the use of ‘hands-on’ and practical approach to use manipulatives and worksheets to improve the geometric understanding was tried and tested in this study. The assumption was that such experiences would make the learning of geometry more relevant and enjoyable for learners from limited financial and underprivileged circumstances. A quasi-experimental design was chosen. A total of 359 learners from five purposively selected schools in Mthatha district in the Eastern Cape Province participated in this study. Qualitative data through interviews were gathered. The data were analysed using IBM SPSS Version 19 and Microsoft Excel. Findings indicated that there was a notable improvement in the performance of learners who were taught by the application of the van Hiele theory. The results revealed that most of the learners were not ready for the application of deductive principles of geometry in terms of formal proof in senior secondary school geometry. Based on the results, some recommendations are made to enhance the teaching and learning of geometry in senior secondary schools.
- Full Text:
- Date Issued: 2012
The feasibility of monetary integration within the SADC region
- Authors: Nindi, Angelique Gugulethu
- Date: 2012
- Subjects: Southern African Development Community Monetary policy -- Africa, Southern Macroeconomics Africa, Southern -- Economic policy
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:1021 , http://hdl.handle.net/10962/d1002756
- Description: The Southern African Development Community (SADC) aims to have a regional central bank by 2016 and a common currency by 2018. The member states are at the early stages of the process of regional economic integration, having launched a free trade area in 2008. Monetary integration is an advanced stage of regional economic integration that requires progressive changes in the participating countries. The purpose of this study is to determine the feasibility of monetary integration within the SADC countries and hence, provide policy recommendations to guide the integration process. To accomplish this, the study analyses the extent to which the member states meet the criteria for an optimum currency area (OCA) as well as the degree to which their economies are converging. The study finds that the main macroeconomic objectives of SADC countries differ due to a difference in the relative importance of monetary policy instruments in member states, which influences each country’s commitment towards achieving the macroeconomic convergence targets and harmonising policies. A more appropriate approach to macroeconomic convergence would be to allow for variable speed, geometry and depth in each country as premature adherence to convergence targets could prevent a harmonisation of the economies in the future and possibly destabilise the union. In addition, the study investigates the importance and similarities of the monetary aggregate channel, the interest rate channel, the exchange rate channel and the credit channel in the transmission of monetary policy using VAR analysis. This is important when considering monetary integration because differences in transmission mechanisms can result in asymmetric behaviour between member states, which in turn will prevent harmonisation of their economies. The results of the analysis suggest that SADC member states display asymmetries in their responses to monetary policy shocks as well as the relative importance of transmission mechanisms. In addition, the results suggest that national monetary policy is generally inefficient in determining economic performance in the member states. Furthermore, the study finds that the failure to meet the OCA criteria implies that the SADC member states will respond asymmetrically to shocks within a monetary union. With no effective alternative adjustment mechanisms in place, the effects of the shocks will endure in union members and possibly widen existing cyclical variation. Hence, monetary integration would not result in harmonisation of the economies of member states. It is therefore, concluded that the SADC countries were not suitable for monetary integration at present.
- Full Text:
- Date Issued: 2012
- Authors: Nindi, Angelique Gugulethu
- Date: 2012
- Subjects: Southern African Development Community Monetary policy -- Africa, Southern Macroeconomics Africa, Southern -- Economic policy
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:1021 , http://hdl.handle.net/10962/d1002756
- Description: The Southern African Development Community (SADC) aims to have a regional central bank by 2016 and a common currency by 2018. The member states are at the early stages of the process of regional economic integration, having launched a free trade area in 2008. Monetary integration is an advanced stage of regional economic integration that requires progressive changes in the participating countries. The purpose of this study is to determine the feasibility of monetary integration within the SADC countries and hence, provide policy recommendations to guide the integration process. To accomplish this, the study analyses the extent to which the member states meet the criteria for an optimum currency area (OCA) as well as the degree to which their economies are converging. The study finds that the main macroeconomic objectives of SADC countries differ due to a difference in the relative importance of monetary policy instruments in member states, which influences each country’s commitment towards achieving the macroeconomic convergence targets and harmonising policies. A more appropriate approach to macroeconomic convergence would be to allow for variable speed, geometry and depth in each country as premature adherence to convergence targets could prevent a harmonisation of the economies in the future and possibly destabilise the union. In addition, the study investigates the importance and similarities of the monetary aggregate channel, the interest rate channel, the exchange rate channel and the credit channel in the transmission of monetary policy using VAR analysis. This is important when considering monetary integration because differences in transmission mechanisms can result in asymmetric behaviour between member states, which in turn will prevent harmonisation of their economies. The results of the analysis suggest that SADC member states display asymmetries in their responses to monetary policy shocks as well as the relative importance of transmission mechanisms. In addition, the results suggest that national monetary policy is generally inefficient in determining economic performance in the member states. Furthermore, the study finds that the failure to meet the OCA criteria implies that the SADC member states will respond asymmetrically to shocks within a monetary union. With no effective alternative adjustment mechanisms in place, the effects of the shocks will endure in union members and possibly widen existing cyclical variation. Hence, monetary integration would not result in harmonisation of the economies of member states. It is therefore, concluded that the SADC countries were not suitable for monetary integration at present.
- Full Text:
- Date Issued: 2012
The further development, optimisation and application of a Yarn Dismantler
- Authors: Fassihi, Ali Akbar
- Date: 2012
- Subjects: Textile industry , Cotton yarn industry
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:10452 , http://hdl.handle.net/10948/d1016066
- Description: The fibre properties of cotton, which vary widely according to genetic and environmental conditions, determine its price and textile processing performance and product quality. It is therefore hardly surprising that cotton fibre properties are routinely measured for trading and quality control purposes, with a great deal of research having been, and still being, devoted towards developing instruments which enable the various fibre properties to be measured rapidly and accurately. In many cases, it is also necessary to be able to measure properties of cotton fibres when they have already been converted into yarn and fabric form. To do so, the yarn has to be dismantled into its component fibres, preferably without significantly changing the fibre properties. This could only be done by manually untwisting the yarn and carefully extracting the fibres from the untwisted yarn, care being taken not to break or lose any fibres in the process. This is a time consuming, laborious and labour intensive process. In view of this, a „yarn dismantler‟ which could automatically, cost effectively and within acceptable time frames, dismantle a cotton yarn into its constituent fibres, without undue damage or changes to the fibres, was developed and patented. This thesis reports the results of research undertaken to further develop, evaluate and optimize the yarn dismantler into the final prototype, as well as those relating to its practical applications, including tracking changes in fibre properties during miniature and pilot scale processing, up to, and including the yarn stage. Initial research undertaken on the original bench and first prototype models indicated that, although they produced very promising results, certain improvements and modifications were necessary, if the dismantler was to perform in an efficient and operator friendly manner at the required speeds. These included changes in the axial position of the untwisting spindle and the perforated screen of the suction drum, increasing the air suction at the perforated drum, installing a new motor for the untwisting spindle drive, separating the drives to the different parts of the unit in order to control them independently, integrating a more effective steaming unit into the unit etc. It was found that the dismantling rate had to be set to equal about 95 percent of the original twist in the yarn, and that steaming of the dismantled (untwisted) yarn on the perforated drum was necessary in order to eliminate any twist liveliness (residual torque) in the dismantled yarn, and enable it to be handled and tested on the AFIS instrument. When the final prototype Yarn Dismantler was produced, incorporating all the above mentioned improvements, it functioned very well at dismantling speeds of at least 2m/min, enabling the length of yarn required for subsequent AFIS testing to be dismantled within an acceptable time of less than 10 minutes, with excellent reproducibility and repeatability of results, also under commercial conditions. It was found that the AFIS measured length characteristics of fibres from the instrument dismantled yarns compared very well with those of fibres from manually dismantled yarns, differences in fibre length generally being less than 1mm, and it was concluded from these and other evaluation tests, that the yarn dismantler produced fibres without any significant fibre breakage. Some limited tests, carried out on commercially produced carded and combed yarns, indicated that short fibre content and dust and trash levels, as measured by the AFIS on fibres from dismantled yarn, together with the corresponding Uster Statistics, could enable a carded cotton yarn to be distinguished from a combed cotton yarn. Statistical analysis of fibre test results obtained at the different stages during miniature and pilot plant scale processing of various cottons, clearly showed that very significant changes in fibre properties could be caused by certain of the processes. For example, significant fibre breakage occurred during the drafting on the spinning frame, prior to twist insertion. The thesis provides detailed results of changes in various fibre properties, including length, short fibre content, maturity, immature fibre content, seed coat neps and fibrous neps, which occurred from the lint to the final yarn, as well as on the relationship between the properties of the fibres from the dismantled yarn and those from the lint. The results obtained have clearly demonstrated the practical value of the yarn dismantler in enabling yarns to be automatically dismantled into their constituent fibres, which can then be tested by an instrument, such as the AFIS, and the test results related to those of the original lint fibres, thereby opening up many fields of research and practical applications, some of which are captured under „Recommended Further Work‟.
- Full Text:
- Date Issued: 2012
- Authors: Fassihi, Ali Akbar
- Date: 2012
- Subjects: Textile industry , Cotton yarn industry
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:10452 , http://hdl.handle.net/10948/d1016066
- Description: The fibre properties of cotton, which vary widely according to genetic and environmental conditions, determine its price and textile processing performance and product quality. It is therefore hardly surprising that cotton fibre properties are routinely measured for trading and quality control purposes, with a great deal of research having been, and still being, devoted towards developing instruments which enable the various fibre properties to be measured rapidly and accurately. In many cases, it is also necessary to be able to measure properties of cotton fibres when they have already been converted into yarn and fabric form. To do so, the yarn has to be dismantled into its component fibres, preferably without significantly changing the fibre properties. This could only be done by manually untwisting the yarn and carefully extracting the fibres from the untwisted yarn, care being taken not to break or lose any fibres in the process. This is a time consuming, laborious and labour intensive process. In view of this, a „yarn dismantler‟ which could automatically, cost effectively and within acceptable time frames, dismantle a cotton yarn into its constituent fibres, without undue damage or changes to the fibres, was developed and patented. This thesis reports the results of research undertaken to further develop, evaluate and optimize the yarn dismantler into the final prototype, as well as those relating to its practical applications, including tracking changes in fibre properties during miniature and pilot scale processing, up to, and including the yarn stage. Initial research undertaken on the original bench and first prototype models indicated that, although they produced very promising results, certain improvements and modifications were necessary, if the dismantler was to perform in an efficient and operator friendly manner at the required speeds. These included changes in the axial position of the untwisting spindle and the perforated screen of the suction drum, increasing the air suction at the perforated drum, installing a new motor for the untwisting spindle drive, separating the drives to the different parts of the unit in order to control them independently, integrating a more effective steaming unit into the unit etc. It was found that the dismantling rate had to be set to equal about 95 percent of the original twist in the yarn, and that steaming of the dismantled (untwisted) yarn on the perforated drum was necessary in order to eliminate any twist liveliness (residual torque) in the dismantled yarn, and enable it to be handled and tested on the AFIS instrument. When the final prototype Yarn Dismantler was produced, incorporating all the above mentioned improvements, it functioned very well at dismantling speeds of at least 2m/min, enabling the length of yarn required for subsequent AFIS testing to be dismantled within an acceptable time of less than 10 minutes, with excellent reproducibility and repeatability of results, also under commercial conditions. It was found that the AFIS measured length characteristics of fibres from the instrument dismantled yarns compared very well with those of fibres from manually dismantled yarns, differences in fibre length generally being less than 1mm, and it was concluded from these and other evaluation tests, that the yarn dismantler produced fibres without any significant fibre breakage. Some limited tests, carried out on commercially produced carded and combed yarns, indicated that short fibre content and dust and trash levels, as measured by the AFIS on fibres from dismantled yarn, together with the corresponding Uster Statistics, could enable a carded cotton yarn to be distinguished from a combed cotton yarn. Statistical analysis of fibre test results obtained at the different stages during miniature and pilot plant scale processing of various cottons, clearly showed that very significant changes in fibre properties could be caused by certain of the processes. For example, significant fibre breakage occurred during the drafting on the spinning frame, prior to twist insertion. The thesis provides detailed results of changes in various fibre properties, including length, short fibre content, maturity, immature fibre content, seed coat neps and fibrous neps, which occurred from the lint to the final yarn, as well as on the relationship between the properties of the fibres from the dismantled yarn and those from the lint. The results obtained have clearly demonstrated the practical value of the yarn dismantler in enabling yarns to be automatically dismantled into their constituent fibres, which can then be tested by an instrument, such as the AFIS, and the test results related to those of the original lint fibres, thereby opening up many fields of research and practical applications, some of which are captured under „Recommended Further Work‟.
- Full Text:
- Date Issued: 2012
The heuristic significance of enacted visualisation
- Authors: Samson, Duncan Alistair
- Date: 2012
- Subjects: Heuristic Visualization Problem solving Pattern perception Problem solving -- Ability testing Mathematics -- Study and teaching Education -- Research Interdisciplinary approach to knowledge
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:1552 , http://hdl.handle.net/10962/d1003434
- Description: This study is centred on an analysis of pupils' lived experience while engaged in the generalisation of linear sequences/progressions presented in a pictorial context. The study is oriented within the conceptual framework of qualitative research, and is anchored within an interpretive paradigm. A case study methodological strategy was adopted, the research participants being the members of a mixed gender, high ability Grade 9 class of 23 pupils at an independent school in South Africa. The analytical framework is structured around a combination of complementary multiple perspectives provided by three theoretical ideas, enactivism, figural apprehension, and knowledge objectification. An important aspect of this analytical framework is the sensitivity it shows to the visual, phenomenological and semiotic aspects of figural pattern generalisation. It is the central thesis of this study that the combined complementary multiple perspectives of enactivism, figural apprehension and knowledge objectification provide a powerful depth of analysis to the exploration of the inter-relationship between the embodied processes of pattern generalisation and the visualisation of pictorial cues. The richly textured tapestry of activity captured through a multi-systemic semiotic analysis of participants' generalisation activity stands testament to this central thesis. Insights gleaned from this study are presented as practical strategies which support and encourage a multiple representational approach to pattern generalisation in the pedagogical context of the classroom.
- Full Text:
- Date Issued: 2012
- Authors: Samson, Duncan Alistair
- Date: 2012
- Subjects: Heuristic Visualization Problem solving Pattern perception Problem solving -- Ability testing Mathematics -- Study and teaching Education -- Research Interdisciplinary approach to knowledge
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:1552 , http://hdl.handle.net/10962/d1003434
- Description: This study is centred on an analysis of pupils' lived experience while engaged in the generalisation of linear sequences/progressions presented in a pictorial context. The study is oriented within the conceptual framework of qualitative research, and is anchored within an interpretive paradigm. A case study methodological strategy was adopted, the research participants being the members of a mixed gender, high ability Grade 9 class of 23 pupils at an independent school in South Africa. The analytical framework is structured around a combination of complementary multiple perspectives provided by three theoretical ideas, enactivism, figural apprehension, and knowledge objectification. An important aspect of this analytical framework is the sensitivity it shows to the visual, phenomenological and semiotic aspects of figural pattern generalisation. It is the central thesis of this study that the combined complementary multiple perspectives of enactivism, figural apprehension and knowledge objectification provide a powerful depth of analysis to the exploration of the inter-relationship between the embodied processes of pattern generalisation and the visualisation of pictorial cues. The richly textured tapestry of activity captured through a multi-systemic semiotic analysis of participants' generalisation activity stands testament to this central thesis. Insights gleaned from this study are presented as practical strategies which support and encourage a multiple representational approach to pattern generalisation in the pedagogical context of the classroom.
- Full Text:
- Date Issued: 2012
The impact of the Consumer Protection Act, 2008 on the accomodation segment of the tourism industry
- Authors: Tait, Andrew Mark
- Date: 2012
- Subjects: South Africa -- Consumer Protection Act, 2008 , Consumer protection -- Law and legislation -- South Africa , Tourism
- Language: English
- Type: Thesis , Doctoral , LLD
- Identifier: vital:10247 , http://hdl.handle.net/10948/d1019922
- Description: The tourism industry is critically important for the economic well-being of South Africa. This realisation elicited a greater focus on the industry, including greater government regulation thereof. Although the concept of a tourist (consumer of tourism services) will not readily conjure up someone in need of protection, tourists are often exposed to exploitation through unfair business practices. Tourists, by definition, are outside their normal places of residence and often strangers to the environment within which they find themselves. For the important tourism industry to achieve its economic potential the protection of the tourist must be paramount. The introduction of the Consumer Protection Act, 2008 in 2010 was heralded as a new dawn for consumers. The CPA provides consumers, including domestic and foreign tourists, with extensive consumer rights. As the CPA is the first comprehensive legislation aimed at consumer protection the impact of the Act is far from known. The CPA caused considerable uncertainty in the tourism industry establishing a clear need to determine its impact on the segments of the industry. This study focuses on the accommodation segment. The aim of the study therefore is to ascertain the impact of selected consumer rights on the accommodation segment of the tourism industry. An overview of the tourism industry reveals that tourists are becoming more experienced, demanding and discerning. The regulation of the industry is explained. Particularly relevant are latest developments in South Africa, particularly the Draft Tourism Bill, 2011 and the National Tourism Sector Strategy. The consumer protection regime applicable prior to the coming into effect of the CPA was characterised more by ad hoc legislative arrangements than any systematic programme of consumer protection. Consumers were reliant on the common law. However, as part of a larger scheme to improve the socio-economic well-being of the people of South Africa, the government introduced a number of statutes including the CPA. The CPA introduced wide-ranging rights for the protection of consumers and mechanisms to provide effective redress. Selected consumer rights are critically analysed to assess the impact of these rights on the accommodation segment. These include the consumer’s right to equality in the market place; the right to privacy; the right to cancel advance bookings; the right to documentation in plain language; the right to quality service; and the right that a supplier having possession of the property of guest must account for such property. Another important aspect relates to the use of exemption provisions. The use of exemption provisions by suppliers is severely curtailed by the CPA. The use of prepaid vouchers, trade coupons and similar promotions, and customer loyalty programmes are also considered and the rights and obligations for consumers and suppliers respectively are elucidated. Many of the rights considered will have a significant impact on accommodation establishments. Elsewhere the impact may not appear to be as significant as the CPA is merely codifying an existing right or remedy. However, codifying the right, providing examples of the conduct prohibited and providing enforcement mechanisms will increase the efficacy of these rights.
- Full Text:
- Date Issued: 2012
- Authors: Tait, Andrew Mark
- Date: 2012
- Subjects: South Africa -- Consumer Protection Act, 2008 , Consumer protection -- Law and legislation -- South Africa , Tourism
- Language: English
- Type: Thesis , Doctoral , LLD
- Identifier: vital:10247 , http://hdl.handle.net/10948/d1019922
- Description: The tourism industry is critically important for the economic well-being of South Africa. This realisation elicited a greater focus on the industry, including greater government regulation thereof. Although the concept of a tourist (consumer of tourism services) will not readily conjure up someone in need of protection, tourists are often exposed to exploitation through unfair business practices. Tourists, by definition, are outside their normal places of residence and often strangers to the environment within which they find themselves. For the important tourism industry to achieve its economic potential the protection of the tourist must be paramount. The introduction of the Consumer Protection Act, 2008 in 2010 was heralded as a new dawn for consumers. The CPA provides consumers, including domestic and foreign tourists, with extensive consumer rights. As the CPA is the first comprehensive legislation aimed at consumer protection the impact of the Act is far from known. The CPA caused considerable uncertainty in the tourism industry establishing a clear need to determine its impact on the segments of the industry. This study focuses on the accommodation segment. The aim of the study therefore is to ascertain the impact of selected consumer rights on the accommodation segment of the tourism industry. An overview of the tourism industry reveals that tourists are becoming more experienced, demanding and discerning. The regulation of the industry is explained. Particularly relevant are latest developments in South Africa, particularly the Draft Tourism Bill, 2011 and the National Tourism Sector Strategy. The consumer protection regime applicable prior to the coming into effect of the CPA was characterised more by ad hoc legislative arrangements than any systematic programme of consumer protection. Consumers were reliant on the common law. However, as part of a larger scheme to improve the socio-economic well-being of the people of South Africa, the government introduced a number of statutes including the CPA. The CPA introduced wide-ranging rights for the protection of consumers and mechanisms to provide effective redress. Selected consumer rights are critically analysed to assess the impact of these rights on the accommodation segment. These include the consumer’s right to equality in the market place; the right to privacy; the right to cancel advance bookings; the right to documentation in plain language; the right to quality service; and the right that a supplier having possession of the property of guest must account for such property. Another important aspect relates to the use of exemption provisions. The use of exemption provisions by suppliers is severely curtailed by the CPA. The use of prepaid vouchers, trade coupons and similar promotions, and customer loyalty programmes are also considered and the rights and obligations for consumers and suppliers respectively are elucidated. Many of the rights considered will have a significant impact on accommodation establishments. Elsewhere the impact may not appear to be as significant as the CPA is merely codifying an existing right or remedy. However, codifying the right, providing examples of the conduct prohibited and providing enforcement mechanisms will increase the efficacy of these rights.
- Full Text:
- Date Issued: 2012
The Management of learners who experience barriers to learning in mainstream Primary Schools in the Eastern Cape
- Wevers, Nicolaas Ebenhaezer Jacobus
- Authors: Wevers, Nicolaas Ebenhaezer Jacobus
- Date: 2012
- Subjects: Inclusive education -- South Africa -- Eastern Cape , Learning disabilities -- South Africa -- Eastern Cape , Mainstreaming in education -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: vital:9453 , http://hdl.handle.net/10948/d1015186
- Description: Much emphasis has been placed on democracy, equality and human rights since the dawn of the democratic South Africa in 1994. Efforts to align the South African education system with the democratic principles of the Constitution, not only in terms of eradicating past racial divides, but also in terms of accessibility to learners who experience barriers to learning are eminent. The South African Government issued various policies to ensure quality, equitable and accessible education for all, irrespective of ability. Theoretically, no learner should therefore being discriminated against on any basis. In practice, however, thousands of learners, especially those who experience barriers to learning are denied the opportunity to receive meaningful development opportunities in many mainstream primary schools, resulting in their early drop out from school without having acquired the basic skills and knowledge to become self sustainable members of their communities. With the adoption of Bronfenbrenner’s ecological model as theoretical framework for this study, the primary aim of this qualitative investigation was to investigate and describe how effective learners who experience barriers to learning are managed in mainstream primary schools and to develop a framework for the creation of more sustainable management systems to ensure that the needs of all learners are met. The findings of the empirical investigation revealed that most learners who experience barriers to learning are currently not managed effectively in mainstream primary schools due to factors situated across the whole education system, to the detriment of learners who experience barriers to learning. Based on the findings of the empirical investigation, this study proposes a framework which will ensure the effective management of learners who experience barriers to learning in mainstream primary schools. The framework include recommendations to be implemented across all layers of the ecological system.
- Full Text:
- Date Issued: 2012
- Authors: Wevers, Nicolaas Ebenhaezer Jacobus
- Date: 2012
- Subjects: Inclusive education -- South Africa -- Eastern Cape , Learning disabilities -- South Africa -- Eastern Cape , Mainstreaming in education -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: vital:9453 , http://hdl.handle.net/10948/d1015186
- Description: Much emphasis has been placed on democracy, equality and human rights since the dawn of the democratic South Africa in 1994. Efforts to align the South African education system with the democratic principles of the Constitution, not only in terms of eradicating past racial divides, but also in terms of accessibility to learners who experience barriers to learning are eminent. The South African Government issued various policies to ensure quality, equitable and accessible education for all, irrespective of ability. Theoretically, no learner should therefore being discriminated against on any basis. In practice, however, thousands of learners, especially those who experience barriers to learning are denied the opportunity to receive meaningful development opportunities in many mainstream primary schools, resulting in their early drop out from school without having acquired the basic skills and knowledge to become self sustainable members of their communities. With the adoption of Bronfenbrenner’s ecological model as theoretical framework for this study, the primary aim of this qualitative investigation was to investigate and describe how effective learners who experience barriers to learning are managed in mainstream primary schools and to develop a framework for the creation of more sustainable management systems to ensure that the needs of all learners are met. The findings of the empirical investigation revealed that most learners who experience barriers to learning are currently not managed effectively in mainstream primary schools due to factors situated across the whole education system, to the detriment of learners who experience barriers to learning. Based on the findings of the empirical investigation, this study proposes a framework which will ensure the effective management of learners who experience barriers to learning in mainstream primary schools. The framework include recommendations to be implemented across all layers of the ecological system.
- Full Text:
- Date Issued: 2012
The past and present limnology of the Soetendalsvlei wetlands, Agulhas coast, South Africa
- Authors: Gordon, Nuette
- Date: 2012
- Subjects: Limnology -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:10619 , http://hdl.handle.net/10948/d1009430 , Limnology -- South Africa
- Description: As climatic conditions continue to change globally, there is a need to assess past environmental change in relation to changing water balance, temperature and sea-level. By understanding the extent of past environmental change, and how anthropogenic impacts have affected ecosystems, better and more accurate future predictions of change can be made. Through the use of the sedimentary record within coastal wetlands, geochemical, (organic content and stable isotopes) and biological (diatoms) proxies were utilised to determine; (i) the baseline water quality record for Soetendalsvlei, one of only a few coastal lakes in South Africa, (ii) the effect of agriculture and mouth manipulation of the Heuningnes Estuary on the microalgae ecology and (iii) the link between palaeo-salinity and trophic status on a regional basis between Soetendalsvlei and Groenvlei, situated 320 km apart. Present water quality and phytoplankton biomass and community structure were assessed for Soetendalsvlei and its associated wetlands, Voëlvlei and Waskraalsvlei to determine the current health of these systems and to obtain modern diatom analogues to be used in the palaeolimnological reconstruction of the coastal lake. Diatoms were not dominant during this study period. Chlorophytes and flagellates were the dominant phytoplankton groups throughout the different wetlands. With the exception of Voëlvlei, the wetlands were all in good health, although SRP concentrations were within the eutrophic to hypertrophic range and are cause for concern. In Voëlvlei, phytoplankton biomass was within the eutrophic range with chlorophyll a concentrations ranging between 20 – 400 ug.l-1 Cyanobacteria, a further indicator of eutrophic conditions, were dominant during the warmer summer periods. Rainfall and freshwater inflow had a significant effect on the biomass and composition of the phytoplankton and acted as a resetting mechanism for all the wetlands as water quality conditions improved thereafter. Comparisons of the water quality and phytoplankton community between the upper reaches of the Heuningnes Estuary and Soetendalsvlei, indicated that artificial breaching of the estuary mouth significantly impacted the connectivity between these two systems, with marine intrusion extending into the upper reaches, while freshwater conditions dominate in the coastal lake. Unfortunately for the palaeolimnological study diatom preservation was poor, however, geochemistry and stable isotope analyses did provide adequate evidence of marine transgression (~8000 yr BP and 4000-2000 yr BP) and regression events comparable to other South African sea-level models developed for the east and west coast. High organic matter content (i.e. higher trophic state) and estuarine POC (C4 vegetation) were associated with periods of marine regression, i.e. increased freshwater, whereas marine transgression events were associated with low organic content and marine POC and DOC. This is comparable to studies conducted in Uruguay (South America) where palaeo-salinity was related to trophic status, i.e. increased freshwater input was associated with high nutrients. Comparisons of the palaeo-record with recorded historical occurrences of droughts and floods, also provided a means of assessing the sedimentary record and to infer anthropogenic impacts after 1850 AD. Overall it can be concluded that coastal lakes of both continents in the Southern Hemisphere displayed similar trophic responses to sea-level fluctuations during the Holocene. This adds valuable information to global sea-level change models.
- Full Text:
- Date Issued: 2012
- Authors: Gordon, Nuette
- Date: 2012
- Subjects: Limnology -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:10619 , http://hdl.handle.net/10948/d1009430 , Limnology -- South Africa
- Description: As climatic conditions continue to change globally, there is a need to assess past environmental change in relation to changing water balance, temperature and sea-level. By understanding the extent of past environmental change, and how anthropogenic impacts have affected ecosystems, better and more accurate future predictions of change can be made. Through the use of the sedimentary record within coastal wetlands, geochemical, (organic content and stable isotopes) and biological (diatoms) proxies were utilised to determine; (i) the baseline water quality record for Soetendalsvlei, one of only a few coastal lakes in South Africa, (ii) the effect of agriculture and mouth manipulation of the Heuningnes Estuary on the microalgae ecology and (iii) the link between palaeo-salinity and trophic status on a regional basis between Soetendalsvlei and Groenvlei, situated 320 km apart. Present water quality and phytoplankton biomass and community structure were assessed for Soetendalsvlei and its associated wetlands, Voëlvlei and Waskraalsvlei to determine the current health of these systems and to obtain modern diatom analogues to be used in the palaeolimnological reconstruction of the coastal lake. Diatoms were not dominant during this study period. Chlorophytes and flagellates were the dominant phytoplankton groups throughout the different wetlands. With the exception of Voëlvlei, the wetlands were all in good health, although SRP concentrations were within the eutrophic to hypertrophic range and are cause for concern. In Voëlvlei, phytoplankton biomass was within the eutrophic range with chlorophyll a concentrations ranging between 20 – 400 ug.l-1 Cyanobacteria, a further indicator of eutrophic conditions, were dominant during the warmer summer periods. Rainfall and freshwater inflow had a significant effect on the biomass and composition of the phytoplankton and acted as a resetting mechanism for all the wetlands as water quality conditions improved thereafter. Comparisons of the water quality and phytoplankton community between the upper reaches of the Heuningnes Estuary and Soetendalsvlei, indicated that artificial breaching of the estuary mouth significantly impacted the connectivity between these two systems, with marine intrusion extending into the upper reaches, while freshwater conditions dominate in the coastal lake. Unfortunately for the palaeolimnological study diatom preservation was poor, however, geochemistry and stable isotope analyses did provide adequate evidence of marine transgression (~8000 yr BP and 4000-2000 yr BP) and regression events comparable to other South African sea-level models developed for the east and west coast. High organic matter content (i.e. higher trophic state) and estuarine POC (C4 vegetation) were associated with periods of marine regression, i.e. increased freshwater, whereas marine transgression events were associated with low organic content and marine POC and DOC. This is comparable to studies conducted in Uruguay (South America) where palaeo-salinity was related to trophic status, i.e. increased freshwater input was associated with high nutrients. Comparisons of the palaeo-record with recorded historical occurrences of droughts and floods, also provided a means of assessing the sedimentary record and to infer anthropogenic impacts after 1850 AD. Overall it can be concluded that coastal lakes of both continents in the Southern Hemisphere displayed similar trophic responses to sea-level fluctuations during the Holocene. This adds valuable information to global sea-level change models.
- Full Text:
- Date Issued: 2012
The perception of educators and subject advisors on the bearing that the South African mathematics curriculum design has on underachievement in schools in the King Williams Town education district of the Eastern Cape
- Authors: Sibanda, Bonani
- Date: 2012
- Subjects: Curriculum-based assessment -- South Africa -- Eastern Cape , Curriculum evaluation -- South Africa -- Eastern Cape , Curriculum planning -- South Africa -- Eastern Cape , Mathematics -- Study and teaching -- South Africa -- Eastern Cape , Mathematics teachers -- South Africa -- Eastern Cape , High school teachers -- South Africa -- Eastern Cape , High school students -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Doctoral , PhD (Education)
- Identifier: vital:16198 , http://hdl.handle.net/10353/d1013106 , Curriculum-based assessment -- South Africa -- Eastern Cape , Curriculum evaluation -- South Africa -- Eastern Cape , Curriculum planning -- South Africa -- Eastern Cape , Mathematics -- Study and teaching -- South Africa -- Eastern Cape , Mathematics teachers -- South Africa -- Eastern Cape , High school teachers -- South Africa -- Eastern Cape , High school students -- South Africa -- Eastern Cape
- Description: The present study investigates the National Curriculum Statement (NCS) Mathematics curriculum Design issues which have a bearing on underachievement at Grade 12 in selected schools in the King Williamstown Education District. It stems from the premise that curriculum design is plausible explanation for Mathematics achievement. In pursuit of this line of thought, the study looked at curriculum design types such as linear, sequential, and spiral arrangement of contents, as well as curriculum design aspects such as sequencing, progression, integration, pacing and organisation of contents. The study also looked at the perceptions educators and subject advisors have with respect to the bearing that these aspects have on underachievement in Mathematics. The interpretive paradigm was used to frame and focus the study. The sample included five schools selected on purpose, with underperformance in Mathematics as an inclusion criterion. These schools constituted the cases of this research. Data was obtained from the interviews which were conducted with the Mathematics educators of the selected schools, and the Mathematics subject advisor of the district to find out about their perceptions with regard to the impact of Mathematics curriculum design on students’ underachievement in Grade 12. In addition, the contents of the National Curriculum Statement for Mathematics documents were analysed. The findings revealed that the scope (contents coverage) is too wide, and that the skills which are supposed to be developed in learners per term are not fully developed. Time allocation is unreasonably limited as a result learners are unable to cover the scope for the term. Revisiting of topics done every year in a spiral fashion is good but the balance between superficiality and depth is not achieved, and that it is done without checking and understanding learners’ previous knowledge on the topic. The sequencing of certain topics has to be looked into and revised. The study also revealed that Mathematics curriculum design, link and progression from primary to high school is good but not all details covered which leave students with content gaps that impede the learning of certain topics. The researcher came out with the following recommendations: From this case study, it appears that teachers still need more empowerment in NCS. Educators still need training on the NCS so they can be confident with the Mathematics NCS content. In most schools the scope is not covered and skills that are supposed to be developed in learners every term are not developed because of slow learners and the time factor. Therefore, the Department of education needs to give the scope taking into consideration the slow learners and make sure that the time they give every term also takes into consideration the time used for tests. It also appears that the learners are slow because of the language barrier. Educators spend a lot of time saying the same things to the learners so that they can understand. Since the learners do almost all the subjects in English and write their examination in English if they are from an English medium school, it would be a good idea for the DOE to introduce English to the learners as early as grade R, as in the model C schools. If that is done, it might remove the language barrier and hence reduce underachievement in Mathematics. It appears that the educators revisit topics every year but do not balance superficiality and depth. Educators should be encouraged to take every topic seriously every year and not just repeat what they covered in the previous grade. They should use it as a base for the new content. If that is done, it might help the achievement in Mathematics.
- Full Text:
- Date Issued: 2012
- Authors: Sibanda, Bonani
- Date: 2012
- Subjects: Curriculum-based assessment -- South Africa -- Eastern Cape , Curriculum evaluation -- South Africa -- Eastern Cape , Curriculum planning -- South Africa -- Eastern Cape , Mathematics -- Study and teaching -- South Africa -- Eastern Cape , Mathematics teachers -- South Africa -- Eastern Cape , High school teachers -- South Africa -- Eastern Cape , High school students -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Doctoral , PhD (Education)
- Identifier: vital:16198 , http://hdl.handle.net/10353/d1013106 , Curriculum-based assessment -- South Africa -- Eastern Cape , Curriculum evaluation -- South Africa -- Eastern Cape , Curriculum planning -- South Africa -- Eastern Cape , Mathematics -- Study and teaching -- South Africa -- Eastern Cape , Mathematics teachers -- South Africa -- Eastern Cape , High school teachers -- South Africa -- Eastern Cape , High school students -- South Africa -- Eastern Cape
- Description: The present study investigates the National Curriculum Statement (NCS) Mathematics curriculum Design issues which have a bearing on underachievement at Grade 12 in selected schools in the King Williamstown Education District. It stems from the premise that curriculum design is plausible explanation for Mathematics achievement. In pursuit of this line of thought, the study looked at curriculum design types such as linear, sequential, and spiral arrangement of contents, as well as curriculum design aspects such as sequencing, progression, integration, pacing and organisation of contents. The study also looked at the perceptions educators and subject advisors have with respect to the bearing that these aspects have on underachievement in Mathematics. The interpretive paradigm was used to frame and focus the study. The sample included five schools selected on purpose, with underperformance in Mathematics as an inclusion criterion. These schools constituted the cases of this research. Data was obtained from the interviews which were conducted with the Mathematics educators of the selected schools, and the Mathematics subject advisor of the district to find out about their perceptions with regard to the impact of Mathematics curriculum design on students’ underachievement in Grade 12. In addition, the contents of the National Curriculum Statement for Mathematics documents were analysed. The findings revealed that the scope (contents coverage) is too wide, and that the skills which are supposed to be developed in learners per term are not fully developed. Time allocation is unreasonably limited as a result learners are unable to cover the scope for the term. Revisiting of topics done every year in a spiral fashion is good but the balance between superficiality and depth is not achieved, and that it is done without checking and understanding learners’ previous knowledge on the topic. The sequencing of certain topics has to be looked into and revised. The study also revealed that Mathematics curriculum design, link and progression from primary to high school is good but not all details covered which leave students with content gaps that impede the learning of certain topics. The researcher came out with the following recommendations: From this case study, it appears that teachers still need more empowerment in NCS. Educators still need training on the NCS so they can be confident with the Mathematics NCS content. In most schools the scope is not covered and skills that are supposed to be developed in learners every term are not developed because of slow learners and the time factor. Therefore, the Department of education needs to give the scope taking into consideration the slow learners and make sure that the time they give every term also takes into consideration the time used for tests. It also appears that the learners are slow because of the language barrier. Educators spend a lot of time saying the same things to the learners so that they can understand. Since the learners do almost all the subjects in English and write their examination in English if they are from an English medium school, it would be a good idea for the DOE to introduce English to the learners as early as grade R, as in the model C schools. If that is done, it might remove the language barrier and hence reduce underachievement in Mathematics. It appears that the educators revisit topics every year but do not balance superficiality and depth. Educators should be encouraged to take every topic seriously every year and not just repeat what they covered in the previous grade. They should use it as a base for the new content. If that is done, it might help the achievement in Mathematics.
- Full Text:
- Date Issued: 2012
The relationship between authentic leadership, psychological capital, psychological climate, team commitment and the intention to quit in a South African manufacturing organisation
- Authors: Munyaka, Sharon Audley
- Date: 2012
- Subjects: Leadership -- South Africa , Organizational commitment -- South Africa , Work environment -- South Africa , Employees -- Resignation -- South Africa , Tire industry workers -- South Africa
- Language: English
- Type: Thesis , Doctoral , DCom
- Identifier: vital:9418 , http://hdl.handle.net/10948/d1021088
- Description: Grounded in the positive psychology paradigm the recently recognised core construct of psychological capital was focussed in a South African study. A non-experimental, correlational study (n=204) examined the relationship between authentic leadership, psychological capital, psychological climate, team commitment and intention to quit. The present study was exploratory in nature and the pattern of relationships being investigated had not been previously tested in a South African context. A self-administered composite questionnaire consisting of five psychological scales were distributed to employees in the junior to senior management level at a global tyre manufacturing organisation based in Port Elizabeth, South Africa. The five scales were the Authentic Leadership Questionnaire by Walumbwa, Psychological Capital Questionnaire by Luthans, Psychological Climate by Koys and DeCotiis, Team Commitment by Bennett and the Intention to Quit Scale by Cohen. All the measures applied on the South African sample were developed outside South Africa and model equivalence had to be established. The content and structure of the measures were investigated through confirmatory factor analysis and exploratory factor analysis. With the exception of the Cohen scale of intention to quit, all other measures changed their factorial structures to suit the present data. The propositions in the study were tested through descriptive statistics, t-tests, ANOVA, post hoc tests, Cohen’s d, Pearson product-moment correlation and multiple regressions. Structural equation models were built to test the relationships between the scales and sub scales of authentic leadership, psychological capital, psychological climate, team commitment and intention to quit. Results of the analyses carried out, show significantly strong relationships between the variables. Of note is the marked relationship between authentic leadership and psychological climate. Most of the propositions were accepted in light of the relationships that emerged. The proposition indicating structural equation models was rejected because none of the models built in the study successfully produced an adequate fit on the data. Contributions of the study were in terms of the portability of the measurement instruments applied in the study as well as the relationships that emerged. Re-validation of the measures is required to enable clarity on how the variables in the study are interpreted across cultural contexts. Directions for future research include extending the study to other samples and other cultures. Measuring social desirability of the instruments could possibly provide clarity on how the different samples respond to the measures. Studies that compare the reading ability as well as the ability to comprehend the items in the measures would provide valuable information.
- Full Text:
- Date Issued: 2012
- Authors: Munyaka, Sharon Audley
- Date: 2012
- Subjects: Leadership -- South Africa , Organizational commitment -- South Africa , Work environment -- South Africa , Employees -- Resignation -- South Africa , Tire industry workers -- South Africa
- Language: English
- Type: Thesis , Doctoral , DCom
- Identifier: vital:9418 , http://hdl.handle.net/10948/d1021088
- Description: Grounded in the positive psychology paradigm the recently recognised core construct of psychological capital was focussed in a South African study. A non-experimental, correlational study (n=204) examined the relationship between authentic leadership, psychological capital, psychological climate, team commitment and intention to quit. The present study was exploratory in nature and the pattern of relationships being investigated had not been previously tested in a South African context. A self-administered composite questionnaire consisting of five psychological scales were distributed to employees in the junior to senior management level at a global tyre manufacturing organisation based in Port Elizabeth, South Africa. The five scales were the Authentic Leadership Questionnaire by Walumbwa, Psychological Capital Questionnaire by Luthans, Psychological Climate by Koys and DeCotiis, Team Commitment by Bennett and the Intention to Quit Scale by Cohen. All the measures applied on the South African sample were developed outside South Africa and model equivalence had to be established. The content and structure of the measures were investigated through confirmatory factor analysis and exploratory factor analysis. With the exception of the Cohen scale of intention to quit, all other measures changed their factorial structures to suit the present data. The propositions in the study were tested through descriptive statistics, t-tests, ANOVA, post hoc tests, Cohen’s d, Pearson product-moment correlation and multiple regressions. Structural equation models were built to test the relationships between the scales and sub scales of authentic leadership, psychological capital, psychological climate, team commitment and intention to quit. Results of the analyses carried out, show significantly strong relationships between the variables. Of note is the marked relationship between authentic leadership and psychological climate. Most of the propositions were accepted in light of the relationships that emerged. The proposition indicating structural equation models was rejected because none of the models built in the study successfully produced an adequate fit on the data. Contributions of the study were in terms of the portability of the measurement instruments applied in the study as well as the relationships that emerged. Re-validation of the measures is required to enable clarity on how the variables in the study are interpreted across cultural contexts. Directions for future research include extending the study to other samples and other cultures. Measuring social desirability of the instruments could possibly provide clarity on how the different samples respond to the measures. Studies that compare the reading ability as well as the ability to comprehend the items in the measures would provide valuable information.
- Full Text:
- Date Issued: 2012
The relationship between health and safety and human risk taking behaviour in the South African electrical construction industry
- Authors: Du Toit, Willem Johannes
- Date: 2012
- Subjects: Electrical engineering -- Safety measures , Electrical engineering -- Health aspects , Construction industry -- Safety measures , Psychology, industrial
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:9691 , http://hdl.handle.net/10948/d1009529 , Electrical engineering -- Safety measures , Electrical engineering -- Health aspects , Construction industry -- Safety measures , Psychology, industrial
- Description: Mankind, and the development of people, exists due to risk-taking behaviour. It is not that humans should not take risks, but rather the ability to identify the magnitude of risk exposure in order that mankind‟s actions would be so selected as to mitigate exposed risk factors, that no harm should befall them. The approach to health and safety (H&S) has always been to manage H&S environmental factors that could have a negative impact on people, capital, and organisational systems. However, the critical component of human risk-taking behaviour that would have a far greater impact has rarely been acknowledged as part of the drivers that increase risk exposure. Human behaviour is a major contributing factor in accident causation. Although human error cannot be completely eliminated, it should be identified and correctly managed according to each individual‟s risk-taking profile. The reason people decide to take certain risks under certain conditions and the effect it has on H&S management systems is a key component to managing organisational risk exposure. To quantify the value of individual risk-taking behaviour could provide management with better opportunities of lowering the organisational risk exposure. Human risk-taking behaviour is influenced by each individual‟s perception of risk. Such perception of risk will influence decisions on risk-taking behaviour, which in turn is influenced by the individual‟s psychological profile and environmental factors, including character and the impact of a cultural environment. The electrical construction and maintenance industry differs from other similar industries in that the physical entity of electricity requires not only sensory perception for the identification and evaluation of risk factors, but also requires specialised knowledge and testing equipment to evaluate the parameters of electrical installation, plant or equipment. Without such competence, direct exposure to most electrical installations could be fatal. The optimum human resource (HR) solution for managing the risk potential of high risk-taking behaviour is the rating and allocation of specific job tasks that can match and limit the individual potential for risk-taking behaviour and the impact on organisational incident statistics. Maintaining and optimising employee job performance enables organisations to better achieve pre-set goals and missions. Such improvements being a catalyst for better job performance by setting limitations on high risk-taking behaviour, that will improve H&S performance by lowering incident rates.
- Full Text:
- Date Issued: 2012
- Authors: Du Toit, Willem Johannes
- Date: 2012
- Subjects: Electrical engineering -- Safety measures , Electrical engineering -- Health aspects , Construction industry -- Safety measures , Psychology, industrial
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:9691 , http://hdl.handle.net/10948/d1009529 , Electrical engineering -- Safety measures , Electrical engineering -- Health aspects , Construction industry -- Safety measures , Psychology, industrial
- Description: Mankind, and the development of people, exists due to risk-taking behaviour. It is not that humans should not take risks, but rather the ability to identify the magnitude of risk exposure in order that mankind‟s actions would be so selected as to mitigate exposed risk factors, that no harm should befall them. The approach to health and safety (H&S) has always been to manage H&S environmental factors that could have a negative impact on people, capital, and organisational systems. However, the critical component of human risk-taking behaviour that would have a far greater impact has rarely been acknowledged as part of the drivers that increase risk exposure. Human behaviour is a major contributing factor in accident causation. Although human error cannot be completely eliminated, it should be identified and correctly managed according to each individual‟s risk-taking profile. The reason people decide to take certain risks under certain conditions and the effect it has on H&S management systems is a key component to managing organisational risk exposure. To quantify the value of individual risk-taking behaviour could provide management with better opportunities of lowering the organisational risk exposure. Human risk-taking behaviour is influenced by each individual‟s perception of risk. Such perception of risk will influence decisions on risk-taking behaviour, which in turn is influenced by the individual‟s psychological profile and environmental factors, including character and the impact of a cultural environment. The electrical construction and maintenance industry differs from other similar industries in that the physical entity of electricity requires not only sensory perception for the identification and evaluation of risk factors, but also requires specialised knowledge and testing equipment to evaluate the parameters of electrical installation, plant or equipment. Without such competence, direct exposure to most electrical installations could be fatal. The optimum human resource (HR) solution for managing the risk potential of high risk-taking behaviour is the rating and allocation of specific job tasks that can match and limit the individual potential for risk-taking behaviour and the impact on organisational incident statistics. Maintaining and optimising employee job performance enables organisations to better achieve pre-set goals and missions. Such improvements being a catalyst for better job performance by setting limitations on high risk-taking behaviour, that will improve H&S performance by lowering incident rates.
- Full Text:
- Date Issued: 2012
Transgressive Christian iconography in post-apartheid South African art
- Authors: Von Veh, Karen Elaine
- Date: 2012
- Subjects: Art -- South Africa -- 20th century Art -- South Africa -- 21st century Christian art and symbolism Apartheid in art Art and society -- South Africa -- History -- 20th century Art and society -- South Africa -- History -- 21st century Parody in art
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:2424 , http://hdl.handle.net/10962/d1002220
- Description: In this study I propose that transgressive interpretations of Christian iconography provide a valuable strategy for contemporary artists to engage with perceived social inequalities in postapartheid South Africa. Working in light of Michel Foucault’s idea of an “ontology of the present”, I investigate the ways in which religious iconography has been implicated in the regulation of society. Parodic reworking of Christian imagery in the selected examples is investigated as a strategy to expose these controls and offer a critique of mechanisms which produce normative ‘truths’. I also consider how such imagery has been received and the factors accounting for that reception. The study is contextualized by a brief, literary based, historical overview of Christian religious imagery to explain the strength of feeling evinced by religious images. This includes a review of the conflation of religion and state control of the masses, an analysis of the sovereign controls and disciplinary powers that they wield, and an explication of their illustration in religious iconography. I also identify reasons why such imagery may have seemed compelling to artists working in a post-apartheid context. By locating recent works in terms of those made elsewhere or South African examples prior to the period that is my focus, the works discussed are explored in terms of broader orientations in post-apartheid South African art. Artworks that respond to specific Christian iconography are discussed, including Adam and Eve, The Virgin Mary, Christ, and various saints and sinners. The selected artists whose works form the focus of this study are Diane Victor, Christine Dixie, Majak Bredell, Tracey Rose, Wim Botha, Conrad Botes, Johannes Phokela and Lawrence Lemaoana. Through transgressive depictions of Christian icons these artists address current inequalities in society. The content of their works analysed here includes (among others): the construction of both female and male identities; sexual roles, social roles, and racial identity; the social expectations of contemporary motherhood; repressive role models; Afrikaner heritage; political and social change and its effects; colonial power; sacrifice; murder, rape, and violence in South Africa; abuses of power by role models and politicians; rugby; heroism; and patricide. Christian iconography is a useful communicative tool because it has permeated many cultures over centuries, and the meanings it carries are thus accessible to large numbers of people. Religious imagery is often held sacred or is regarded with a degree of reverence, thus ensuring an emotive response when iconoclasm or transgression of any sort is identified. This study argues that by parodying sacred imagery these artists are able to disturb complacent viewing and encourage viewers to engage critically with some of its underlying implications.
- Full Text:
- Date Issued: 2012
- Authors: Von Veh, Karen Elaine
- Date: 2012
- Subjects: Art -- South Africa -- 20th century Art -- South Africa -- 21st century Christian art and symbolism Apartheid in art Art and society -- South Africa -- History -- 20th century Art and society -- South Africa -- History -- 21st century Parody in art
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:2424 , http://hdl.handle.net/10962/d1002220
- Description: In this study I propose that transgressive interpretations of Christian iconography provide a valuable strategy for contemporary artists to engage with perceived social inequalities in postapartheid South Africa. Working in light of Michel Foucault’s idea of an “ontology of the present”, I investigate the ways in which religious iconography has been implicated in the regulation of society. Parodic reworking of Christian imagery in the selected examples is investigated as a strategy to expose these controls and offer a critique of mechanisms which produce normative ‘truths’. I also consider how such imagery has been received and the factors accounting for that reception. The study is contextualized by a brief, literary based, historical overview of Christian religious imagery to explain the strength of feeling evinced by religious images. This includes a review of the conflation of religion and state control of the masses, an analysis of the sovereign controls and disciplinary powers that they wield, and an explication of their illustration in religious iconography. I also identify reasons why such imagery may have seemed compelling to artists working in a post-apartheid context. By locating recent works in terms of those made elsewhere or South African examples prior to the period that is my focus, the works discussed are explored in terms of broader orientations in post-apartheid South African art. Artworks that respond to specific Christian iconography are discussed, including Adam and Eve, The Virgin Mary, Christ, and various saints and sinners. The selected artists whose works form the focus of this study are Diane Victor, Christine Dixie, Majak Bredell, Tracey Rose, Wim Botha, Conrad Botes, Johannes Phokela and Lawrence Lemaoana. Through transgressive depictions of Christian icons these artists address current inequalities in society. The content of their works analysed here includes (among others): the construction of both female and male identities; sexual roles, social roles, and racial identity; the social expectations of contemporary motherhood; repressive role models; Afrikaner heritage; political and social change and its effects; colonial power; sacrifice; murder, rape, and violence in South Africa; abuses of power by role models and politicians; rugby; heroism; and patricide. Christian iconography is a useful communicative tool because it has permeated many cultures over centuries, and the meanings it carries are thus accessible to large numbers of people. Religious imagery is often held sacred or is regarded with a degree of reverence, thus ensuring an emotive response when iconoclasm or transgression of any sort is identified. This study argues that by parodying sacred imagery these artists are able to disturb complacent viewing and encourage viewers to engage critically with some of its underlying implications.
- Full Text:
- Date Issued: 2012
Travelling shoppers' perceptions on the comprehensive servicescape within the South African retail environment
- Authors: Zinhumwe, Cephas
- Date: 2012
- Subjects: Retail trade -- Customer services -- South Africa , Consumer satisfaction -- South Africa , Consumption (Economics) -- Social aspects , Consumer behavior
- Language: English
- Type: Thesis , Doctoral , DCom
- Identifier: vital:9296 , http://hdl.handle.net/10948/d1013610
- Description: The study is on the influence of comprehensive servicescape on shopping behaviour of road and rail travelling shoppers. The comprehensive servicescape is referred to as synchronization of the multidimensional servicescape dimensions, which are the physical environment, social environment, socially symbolic and the natural dimensions into one entity that the travellers encounter during the shopping exercise. The servicescape cues that include shoppers and the physical set-up of the service firm are important in influencing service quality evaluation and consumer satisfaction. The aim of this study was to establish the impact of servicescape on travelling shoppers’ buying behaviour and shopping motivations amongst different shoppers that were identified within the South African bus and railway stations. The bus and railway station environment induces an interesting type of shopping behaviour amongst the travelers. The purpose of the study was also to explore the travelling shoppers’ expectations and perceptions on the comprehensive servicescape within the bus station’s retail environment. Additionally the study attempted to address important gaps in the South African literature in respect of the influence of socialservicescape on the buyer behaviour and hedonic motivation of travelling shopper. The questionnaires used in the study were constructed along five dimensions of service quality containing statements linked to a five-point Likert-type interval scale anchored by “strongly agree” and “strongly disagree. Self administered questionnaires were used for data collection from the travelling shoppers through “mall intercept technique” and 300 questionnaires were collected from respondents. The academia benefits from this study from the comprehensive servicescape model of the South African bus and railway stations that was developed. The study built on literature by nvestigating the influence of the comprehensive servicescapes as perceived by travelling shoppers within the South African retail environment. Additionally it was shown both theoretically and empirically, that, that service quality in high contact service environment like the bus and railway station can best be explained by an analysis of the comprehensive servicescape or the multidimensional and hierarchical model. As a result of this study retailers will have a full picture on the specific needs, perception and expectations of road and rail travellers in relation to the quality of the stations’ servicescape, which retailers have to improve in order to increase customer patronage. It is assumed that retailers will be aware that store image and the store ambience should meet the challenges of the perceptions, motivations and consumer behaviour of travellers within the comprehensive servicescape of the station. This study provides a trigger effect to spatial planners to design high quality servicescape that will attract travellers for both hedonic and utilitarian shopping. Hirschman and Holbrook (1982) believed that shoppers derive pleasure from the experience of shopping itself, regardless of the joy from acquiring goods, this more so with travelling shoppers. A bus station can be both a growth node and a tourist attraction, if its features are attractive, therefore planners can benefit from this study. In this study theory that forms the bases of the influence of social servicescape on the behaviour of travelling shoppers that frequently visit and participate in shopping at various South African bus station retail outlets is provided. Additionally, this study provided empirical information on the relationships that exist amongst the characteristics of the South African Park Stations’ physical retail environments, user perceptions and interpersonal encounters. The behaviour of shopping travellers was extensively discussed to provide the background of theories and various models concerning shopping behaviour of travellers. Through this work, clarity on consumer behavioural trends of travelling shoppers in the South African retail sector is provided, which assist in differentiating retail products, services and segmentation of markets in a way that could enhance marketing effectiveness amongst the travelling shopping segment. Special attention was paid to factors that motivate road travellers’ choice of stores; the type of products they purchase and their decision making processes. Effort were made to identify, categorize and segment shopper typologies and their shopping behaviours. Effort was also made to discuss extensively the social and physical influences of environments in a retail environment such as that of the bus and railway station. The discussions in this study focussed on describing the comprehensive servicescape model dimensions which shoppers encountered during their shopping activity. The study also indicated the significance of the interaction of service staff with the customers in determining the service quality, customer satisfaction and the future intention of travelers. Additionally this study emphasised the importance of social encounters and perceptiveness to cues within the station, which determine whether they actively or passively are involved in the shopping encounter. The research findings reveal that, travellers perceive the servicescape within the bus station as unattractive and lack appropriate facilities. Furthermore travelers considered the two dimensions (store image and store ambience) of the store’s servicescape as one composite unit of the servicescape. This position is supported in literature, where it is argued that people respond to their environment holistically, rather than to individual stimuli. The travelling shoppers reveal that although they always find the shops from the bus station clean and neat, consumers expect a certain level of ambient environmental conditions to be present. The empirical findings in this study indicate that travelling shoppers are not interested in visiting the stores at the bus and railway station for shopping because merchandise from the bus station stores is poor in quality and unreliable; the surroundings at the station as unpleasant and the bus and railway station stores are congested. Thus, hasty shopping and spending more time or stay longer than planned for shopping at the bus and railway station is not useful to travelling shoppers. Therefore, travellers feel strongly that the shopping environment of the station is not conducive to shopping. These facilities (stations) are only used for travelling purposes; therefore there is a need for improvement in the retail and station facilities in order to increase shopping activities within this servicescape. The research findings reveal that shopping at the bus station seems to be driven by traditional needs such as functional and experiential motivations as well as travelrelated needs such as busstation-atmosphere-related and bus station-infrastructurerelated motivations. It was difficult to deduce a particular typology of shoppers in this environment, but due to the stress related to travelling. Passive shopping was observed amongst travellers, which is not a positive shopping behaviour for retailers.
- Full Text:
- Date Issued: 2012
- Authors: Zinhumwe, Cephas
- Date: 2012
- Subjects: Retail trade -- Customer services -- South Africa , Consumer satisfaction -- South Africa , Consumption (Economics) -- Social aspects , Consumer behavior
- Language: English
- Type: Thesis , Doctoral , DCom
- Identifier: vital:9296 , http://hdl.handle.net/10948/d1013610
- Description: The study is on the influence of comprehensive servicescape on shopping behaviour of road and rail travelling shoppers. The comprehensive servicescape is referred to as synchronization of the multidimensional servicescape dimensions, which are the physical environment, social environment, socially symbolic and the natural dimensions into one entity that the travellers encounter during the shopping exercise. The servicescape cues that include shoppers and the physical set-up of the service firm are important in influencing service quality evaluation and consumer satisfaction. The aim of this study was to establish the impact of servicescape on travelling shoppers’ buying behaviour and shopping motivations amongst different shoppers that were identified within the South African bus and railway stations. The bus and railway station environment induces an interesting type of shopping behaviour amongst the travelers. The purpose of the study was also to explore the travelling shoppers’ expectations and perceptions on the comprehensive servicescape within the bus station’s retail environment. Additionally the study attempted to address important gaps in the South African literature in respect of the influence of socialservicescape on the buyer behaviour and hedonic motivation of travelling shopper. The questionnaires used in the study were constructed along five dimensions of service quality containing statements linked to a five-point Likert-type interval scale anchored by “strongly agree” and “strongly disagree. Self administered questionnaires were used for data collection from the travelling shoppers through “mall intercept technique” and 300 questionnaires were collected from respondents. The academia benefits from this study from the comprehensive servicescape model of the South African bus and railway stations that was developed. The study built on literature by nvestigating the influence of the comprehensive servicescapes as perceived by travelling shoppers within the South African retail environment. Additionally it was shown both theoretically and empirically, that, that service quality in high contact service environment like the bus and railway station can best be explained by an analysis of the comprehensive servicescape or the multidimensional and hierarchical model. As a result of this study retailers will have a full picture on the specific needs, perception and expectations of road and rail travellers in relation to the quality of the stations’ servicescape, which retailers have to improve in order to increase customer patronage. It is assumed that retailers will be aware that store image and the store ambience should meet the challenges of the perceptions, motivations and consumer behaviour of travellers within the comprehensive servicescape of the station. This study provides a trigger effect to spatial planners to design high quality servicescape that will attract travellers for both hedonic and utilitarian shopping. Hirschman and Holbrook (1982) believed that shoppers derive pleasure from the experience of shopping itself, regardless of the joy from acquiring goods, this more so with travelling shoppers. A bus station can be both a growth node and a tourist attraction, if its features are attractive, therefore planners can benefit from this study. In this study theory that forms the bases of the influence of social servicescape on the behaviour of travelling shoppers that frequently visit and participate in shopping at various South African bus station retail outlets is provided. Additionally, this study provided empirical information on the relationships that exist amongst the characteristics of the South African Park Stations’ physical retail environments, user perceptions and interpersonal encounters. The behaviour of shopping travellers was extensively discussed to provide the background of theories and various models concerning shopping behaviour of travellers. Through this work, clarity on consumer behavioural trends of travelling shoppers in the South African retail sector is provided, which assist in differentiating retail products, services and segmentation of markets in a way that could enhance marketing effectiveness amongst the travelling shopping segment. Special attention was paid to factors that motivate road travellers’ choice of stores; the type of products they purchase and their decision making processes. Effort were made to identify, categorize and segment shopper typologies and their shopping behaviours. Effort was also made to discuss extensively the social and physical influences of environments in a retail environment such as that of the bus and railway station. The discussions in this study focussed on describing the comprehensive servicescape model dimensions which shoppers encountered during their shopping activity. The study also indicated the significance of the interaction of service staff with the customers in determining the service quality, customer satisfaction and the future intention of travelers. Additionally this study emphasised the importance of social encounters and perceptiveness to cues within the station, which determine whether they actively or passively are involved in the shopping encounter. The research findings reveal that, travellers perceive the servicescape within the bus station as unattractive and lack appropriate facilities. Furthermore travelers considered the two dimensions (store image and store ambience) of the store’s servicescape as one composite unit of the servicescape. This position is supported in literature, where it is argued that people respond to their environment holistically, rather than to individual stimuli. The travelling shoppers reveal that although they always find the shops from the bus station clean and neat, consumers expect a certain level of ambient environmental conditions to be present. The empirical findings in this study indicate that travelling shoppers are not interested in visiting the stores at the bus and railway station for shopping because merchandise from the bus station stores is poor in quality and unreliable; the surroundings at the station as unpleasant and the bus and railway station stores are congested. Thus, hasty shopping and spending more time or stay longer than planned for shopping at the bus and railway station is not useful to travelling shoppers. Therefore, travellers feel strongly that the shopping environment of the station is not conducive to shopping. These facilities (stations) are only used for travelling purposes; therefore there is a need for improvement in the retail and station facilities in order to increase shopping activities within this servicescape. The research findings reveal that shopping at the bus station seems to be driven by traditional needs such as functional and experiential motivations as well as travelrelated needs such as busstation-atmosphere-related and bus station-infrastructurerelated motivations. It was difficult to deduce a particular typology of shoppers in this environment, but due to the stress related to travelling. Passive shopping was observed amongst travellers, which is not a positive shopping behaviour for retailers.
- Full Text:
- Date Issued: 2012
Vapour phase dehydrogenation of cyclohexane on microstructured reactors
- Authors: Mpuhlu, Batsho
- Date: 2012
- Subjects: Dehydrogenation , Cyclohexane
- Language: English
- Type: Thesis , Doctoral , DTech (Chemistry)
- Identifier: http://hdl.handle.net/10948/8661 , vital:26418
- Description: The work that is described in this thesis forms part of the research and development projects at InnoVenton: NMMU Institute of Chemical Technology in collaboration with Sasol Technologies. The broader view of the project was testing on the so-called “Small Production Platforms” (SPP’s). In particular the main aim of this study was to investigate the effect of micro-structuring on the heterogeneous catalysed, vapour-phase oxidative dehydrogenation of cyclohexane in the presence of air. Ground work studies were done to provide a proper comparison of the micro-structured reactor with a traditional fixed-bed reactor. These included evaluation of a proper vanadium pyrophosphate catalyst for the reaction, testing of reaction parameters for the oxidative dehydrogenation reaction on a fixed-bed reactor and lastly comparing the performance of the micro-structured reactor to that of the fixed-bed reactor Various vanadium pyrophosphate catalysts that were tested for activity included: bulk (VO)2P2O7, bulk (VO)2P2O7 promoted with Fe, (VO)2P2O7 supported on -Al2O3 and Fe promoted (VO)2P2O7 supported on -Al2O3. These catalysts showed significant differences in TOF, however it was not conclusive from the results whether these differences may be traced to increased activity for dehydrogenation for different catalysts since all reactions were run under conditions of oxygen deficiency. It is, however, clear that Fe promotion significantly increase activity, irrespective of the relative degrees of oxidative dehydrogenation and normal dehydrogenation. The Fe promoted catalyst was further tested for long term stability in-view of using it as the catalyst in the micro-structured reactor. These studies showed the catalyst to have a high degree of stability with minimal structural changes under the reaction conditions used. Various response surface models describing the variation in each of the cyclohexane conversion, cyclohexene selectivity, and benzene selectivity, respectively when changing reaction condition, were derived by means of multiple regression. To obtain some idea of the degree and nature of the normal dehydrogenation reaction, the amount of deficit oxygen was estimated from the measured results for cyclohexane conversion and cyclohexene and benzene selectivities. These estimated values were also modelled as described above. The regression models were used to interpret specific trends in the responses for the oxidative dehydrogenation of cyclohexane and account for the oxygen deficit in the system. The performance of a fixed bed tubular reactor (FBR) and micro-structured sandwich reactor (MSSR) were compared over an Fe promoted vanadium pyrophosphate. Reactor performance was evaluated by varying specific reaction conditions (temperature and space velocity). Subsequently the turn-over frequencies, conversion and selectivities from the two reactors were compared. The conversion achieved in the micro-structured reactor was observed to be significantly higher than that achieved in the fixed-bed reactor at all reaction parameters. This is despite the fact that the total amount of catalyst in the micro-structured reactor is approximately 5 times less than that used in the fixed bed reactor. In addition, the contact time (1/MHSV) in the micro-structured reactor is also significantly shorter than in the fixed-bed reactor.
- Full Text:
- Date Issued: 2012
- Authors: Mpuhlu, Batsho
- Date: 2012
- Subjects: Dehydrogenation , Cyclohexane
- Language: English
- Type: Thesis , Doctoral , DTech (Chemistry)
- Identifier: http://hdl.handle.net/10948/8661 , vital:26418
- Description: The work that is described in this thesis forms part of the research and development projects at InnoVenton: NMMU Institute of Chemical Technology in collaboration with Sasol Technologies. The broader view of the project was testing on the so-called “Small Production Platforms” (SPP’s). In particular the main aim of this study was to investigate the effect of micro-structuring on the heterogeneous catalysed, vapour-phase oxidative dehydrogenation of cyclohexane in the presence of air. Ground work studies were done to provide a proper comparison of the micro-structured reactor with a traditional fixed-bed reactor. These included evaluation of a proper vanadium pyrophosphate catalyst for the reaction, testing of reaction parameters for the oxidative dehydrogenation reaction on a fixed-bed reactor and lastly comparing the performance of the micro-structured reactor to that of the fixed-bed reactor Various vanadium pyrophosphate catalysts that were tested for activity included: bulk (VO)2P2O7, bulk (VO)2P2O7 promoted with Fe, (VO)2P2O7 supported on -Al2O3 and Fe promoted (VO)2P2O7 supported on -Al2O3. These catalysts showed significant differences in TOF, however it was not conclusive from the results whether these differences may be traced to increased activity for dehydrogenation for different catalysts since all reactions were run under conditions of oxygen deficiency. It is, however, clear that Fe promotion significantly increase activity, irrespective of the relative degrees of oxidative dehydrogenation and normal dehydrogenation. The Fe promoted catalyst was further tested for long term stability in-view of using it as the catalyst in the micro-structured reactor. These studies showed the catalyst to have a high degree of stability with minimal structural changes under the reaction conditions used. Various response surface models describing the variation in each of the cyclohexane conversion, cyclohexene selectivity, and benzene selectivity, respectively when changing reaction condition, were derived by means of multiple regression. To obtain some idea of the degree and nature of the normal dehydrogenation reaction, the amount of deficit oxygen was estimated from the measured results for cyclohexane conversion and cyclohexene and benzene selectivities. These estimated values were also modelled as described above. The regression models were used to interpret specific trends in the responses for the oxidative dehydrogenation of cyclohexane and account for the oxygen deficit in the system. The performance of a fixed bed tubular reactor (FBR) and micro-structured sandwich reactor (MSSR) were compared over an Fe promoted vanadium pyrophosphate. Reactor performance was evaluated by varying specific reaction conditions (temperature and space velocity). Subsequently the turn-over frequencies, conversion and selectivities from the two reactors were compared. The conversion achieved in the micro-structured reactor was observed to be significantly higher than that achieved in the fixed-bed reactor at all reaction parameters. This is despite the fact that the total amount of catalyst in the micro-structured reactor is approximately 5 times less than that used in the fixed bed reactor. In addition, the contact time (1/MHSV) in the micro-structured reactor is also significantly shorter than in the fixed-bed reactor.
- Full Text:
- Date Issued: 2012
Young veterans, not always social misfits: a sociological discourse of Liberian transmogrification experiences
- Authors: Agbedahin, Komlan
- Date: 2012
- Subjects: Child soldiers -- Liberia Children and war -- Liberia Liberia. Armed Forces -- Demobilization -- Social aspects Liberia -- History -- Civil War, 1989-1996 Liberia -- History -- Civil War, 1999-2003
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3316 , http://hdl.handle.net/10962/d1003104
- Description: This thesis examines the phenomenon of child-soldiering from a different perspective. It seeks to challenge, using a novel approach, earlier studies on the roles of former child-soldiers in post-war societies. It focuses on the subjectivity of young veterans, that is war veterans formerly associated with armed forces and groups as children during the 14-year gruesome civil war which bedevilled Liberia between 1989 and 2003. This civil war claimed roughly 250,000 lives, and saw the active participation of approximately 21,000 child-soldiers. This thesis departs from previous works which mostly painted an apocalyptic picture of young veterans, and explores the nexus between their self-agency, Foucauldian technologies of the self and their transformation in the post-war society. The majority of previous scholarly works which have dominated the field of child-soldiering dwelt on the impact of armed conflict on the child-soldiers, the negative consequences, the causes of child-soldiering, and the rehabilitation and reintegration of the young veterans after their disarmament and demobilization. What this thesis seeks to do however, is to establish that, rather than considering the young veterans simply as social misfits, distraught and dispirited human beings, it should be noted that young veterans through their agency, are capable of ensuring their reintegration into their war-ravaged societies. Sadly, these young former fighters’ self-agency and technologies of the self in defining their civilian trajectories have often been overshadowed by vaunted humanitarian aid and multilayered war-profiteering. This study is underpinned by interpretive constructivism, symbolic interactionism, social identity theory, sociometer theory and expectancy theory, and sheds light on how young veterans’ self-agency, instrumental coalitions, and decision-making processes, synergistically shifted the negative identities foisted on them as a result of their participation in the war.
- Full Text:
- Date Issued: 2012
- Authors: Agbedahin, Komlan
- Date: 2012
- Subjects: Child soldiers -- Liberia Children and war -- Liberia Liberia. Armed Forces -- Demobilization -- Social aspects Liberia -- History -- Civil War, 1989-1996 Liberia -- History -- Civil War, 1999-2003
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3316 , http://hdl.handle.net/10962/d1003104
- Description: This thesis examines the phenomenon of child-soldiering from a different perspective. It seeks to challenge, using a novel approach, earlier studies on the roles of former child-soldiers in post-war societies. It focuses on the subjectivity of young veterans, that is war veterans formerly associated with armed forces and groups as children during the 14-year gruesome civil war which bedevilled Liberia between 1989 and 2003. This civil war claimed roughly 250,000 lives, and saw the active participation of approximately 21,000 child-soldiers. This thesis departs from previous works which mostly painted an apocalyptic picture of young veterans, and explores the nexus between their self-agency, Foucauldian technologies of the self and their transformation in the post-war society. The majority of previous scholarly works which have dominated the field of child-soldiering dwelt on the impact of armed conflict on the child-soldiers, the negative consequences, the causes of child-soldiering, and the rehabilitation and reintegration of the young veterans after their disarmament and demobilization. What this thesis seeks to do however, is to establish that, rather than considering the young veterans simply as social misfits, distraught and dispirited human beings, it should be noted that young veterans through their agency, are capable of ensuring their reintegration into their war-ravaged societies. Sadly, these young former fighters’ self-agency and technologies of the self in defining their civilian trajectories have often been overshadowed by vaunted humanitarian aid and multilayered war-profiteering. This study is underpinned by interpretive constructivism, symbolic interactionism, social identity theory, sociometer theory and expectancy theory, and sheds light on how young veterans’ self-agency, instrumental coalitions, and decision-making processes, synergistically shifted the negative identities foisted on them as a result of their participation in the war.
- Full Text:
- Date Issued: 2012