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A VLBI study of OH masers in a proto-planetary nebula OH 0.9+1.3

  • Authors: McAlpine, Kim
  • Date: 2008
  • Subjects: Very long baseline interferometry , Proto-planetary nebulae , Masers
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:5499 , http://hdl.handle.net/10962/d1005285 , Very long baseline interferometry , Proto-planetary nebulae , Masers
  • Description: This thesis reports the calibration, imaging and analysis of one epoch of VLBA observations of the 1612 MHz OH maser emission from the protoplanetary nebula OH 0.9+1.3. These are the first polarisation VLBI observations of this source and the spatial morphology of the OH emission is resolved on this scale. Proto-planetary nebulae represent the transition phase in the evolution of stars between the asymptotic giant branch (AGB) phase and their emergence as planetary nebulae. A long-standing astronomical question is how the predominantly spherical circumstellar envelopes of AGB stars evolve into the bipolar and axisymmetric structures that are commonly observed in planetary nebula. Proto-planetary nebulae offer a unique opportunity to study this transformation process. The high-resolution VLBI maps produced in this thesis were used to investigate the morphology and kinematics of OH 0.9+1.3 with a view to gaining insight into the development of asymmetries in the circumstellar material. The OH maser emission of OH 0.9+1.3 has a double-peaked profile with one peak blue-shifted and the other red-shifted with respect to the stellar velocity. The total intensity maser maps demonstrate a considerable degree of asymmetry with the blue- and red-shifted emission located in spatially distinct regions of the envelope. The blue-shifted emission is distributed preferentially along an axis at a projected position angle of » 135± ( North through East). The morphology of this source is not consistent with the standard symmetric thin-shell model and an attempt to fit the traditional OH/IR kinematic model of a simple expanding shell to the maser components was found to be unsatisfactory. No definitive evidence of a bipolar outflow was observed either. The high degree of asymmetry observed in the source is consistent with its status as a proto-planetary nebula. The source was imaged in all four Stokes parameters and the fractional linear and circular polarisations of the maser components were derived from the Stokes parameter maps. In all except one of the components the total fractional polarisation was found to be low ( < 15%). The mean fractional linear and circular polarisation were calculated to be 5.54% and 7.11% respectively. The absence of an identifiable Zeeman pair in the Stokes V map prohibited the estimation of the magnetic field in the circumstellar envelope of this source.
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  • Date Issued: 2008

A xylem retrieval pathway in rice leaf blades – evidence of a role for endocytosis?

  • Authors: Botha, Christiaan E J , Aoki, N , Scofield, G N , Liu, Lin , Furbank, R T , White, R G
  • Date: 2008
  • Language: English
  • Type: Article
  • Identifier: vital:6505 , http://hdl.handle.net/10962/d1005930 , http://dx.doi.org/10.1093/jxb/ern150
  • Description: The structure and transport properties of pit membranes at the interface between the metaxylem and xylem parenchyma cells and the possible role of these pit membranes in solute transfer to the phloem was investigated. Electron microscopy revealed a fibrillar, almost tubular matrix within the pit membrane structure between the xylem vessels and xylem parenchyma of leaf blade bundles in rice (Oryza sativa). These pits are involved primarily with regulating water flux to the surrounding xylem parenchyma cells. Vascular parenchyma cells contain large mitochondrial populations, numerous dictyosomes, endomembrane complexes and vesicles in close proximity to the pit membrane. Taken collectively this suggests that endocytosis may occur at this interface. A weak solution of 5,6-carboxyfluorescein diacetate (5,6-CFDA) was applied to cut ends of leaves and after a minimum of 45 minutes, the distribution of the fluorescent cleavage product, 5,6-carboxyfluorescein (5,6-CF) was observed using confocal microscopy. Cleavage of 5,6-CFDA occurred within the xylem parenchyma cells and the non-polar 5,6-CF was then symplasmically transported to other parenchyma elements and ultimately, via numerous pore plasmodesmata, to adjacent thick-walled sieve tubes. Application of Lucifer Yellow, and, separately, Texas Red labelled dextran (10 kDa) to the transpiration stream, confirmed that these membrane-impermeant probes could only have been offloaded from the xylem via the xylem vessel-xylem parenchyma pit membranes, suggesting endocytotic transmembrane transfer of these membrane-impermeant fluorophores. Accumulation within the thick-walled sieve tubes, but not in thin-walled sieve tubes, confirms the presence of a symplasmic phloem loading pathway, via pore plasmodesmata between xylem parenchyma and thick-walled sieve tubes, but not thin-walled sieve tubes.
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  • Date Issued: 2008

Absenteeism management at Willard Batteries

  • Authors: Paul, Gary William
  • Date: 2008
  • Subjects: Absenteeism (Labor) -- Management , Absenteeism (Labor) -- South Africa
  • Language: English
  • Type: Thesis , Masters , MTech
  • Identifier: vital:9383 , http://hdl.handle.net/10948/896 , Absenteeism (Labor) -- Management , Absenteeism (Labor) -- South Africa
  • Description: The main research problem in this study centred around the assessment of the impact of an absenteeism monitoring and management system at Willard Batteries. The main research problem had five sub-problems which were addressed through the following actions: A literature study was conducted to identify the causes and impact of absenteeism in the workplace. The researcher also conducted interviews with the Human Resources Manager, line managers and employees at Willard Batteries to obtain their views of the absenteeism management strategies utilised, as well as the effects of absenteeism in their organisation. The insights gained from these interviews were incorporated into the questionnaire. The absenteeism figures of the organisation for the period 2005 to 2008 were analysed and compared against the internationally accepted absenteeism norm of three percent. An absence rate above three percent is considered as unacceptable and would imply that the current absenteeism management system is not effective. The theoretical study also entailed the reviewing of the legal framework within which absenteeism needs to be managed, as well as the literature that deals with strategies for the effective management of absenteeism. These strategies relate to the recording, calculation, analysis, benchmarking and practical management of absenteeism in the workplace. A survey questionnaire was developed to determine the perceptions of managers, supervisors and employees in relation to the impact of absenteeism on the company as well as the extent to which managers and supervisors were utilising selected absenteeism monitoring and management strategies within the company. The results from the empirical study revealed that management and supervisors were more aware of the impact of absenteeism on the organisation than their employees. It can therefore be concluded that employees perceived their absence from work to have little impact on aspects such as employee morale, cost, production and the customer. This could possibly be due to ineffective communication in terms of the cost and other consequences of absenteeism in the organisation. Employees also felt that managers were effective in taking the necessary disciplinary action with regards to absenteeism-related transgressions, but that they were not diligent in the recording and communication of absence information, as well as comparing absenteeism information inter-departmentally. Absenteeism has proven to be globally pervasive, expensive and extremely disruptive to organisations. Managers and supervisors who employ the various absence monitoring and management strategies, could be more effective in improving employee attendance. Their efforts could be further enhanced if employees are made aware of the negative impact that their absence has on the morale of their fellow employees, the cost to the company, the customer, as well as the achievement of production targets and the quality of outputs.
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  • Date Issued: 2008

Access to educational resources: illustrative examples from rural schools in the Eastern Cape Province

  • Authors: Hendricks, Monica
  • Date: 2008
  • Language: English
  • Type: Book chapter
  • Identifier: vital:7020 , http://hdl.handle.net/10962/d1007200
  • Description: [Introduction] This chapter looks at the causes and effects of the widely varying degree of access to material resources across schools in the Eastern Cape. Starting with a broad overview of schools and classroom resources across the whole province, I go on to examine the Grahamstown education district. I discuss the inequalities in resource provision between groupings of schools in the district: comparing independent and state schools, and also examining disparities across schools in different localities within the government sector. The role of parents in providing resources for their children’s schooling is also discussed, as are the relationships among the various participants in education, such as non-governmental organisations, officials of the Department of Education, and teachers.
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  • Date Issued: 2008

Action research on leadership style, and relationships in an East London law firm

  • Authors: Stoltz, Tania
  • Date: 2008
  • Subjects: Action research Law offices Leadership Law firms--South Africa--East London Law offices--South Africa--East London
  • Language: English
  • Type: Thesis , Masters , MBA
  • Identifier: vital:798 , http://hdl.handle.net/10962/d1004592
  • Description: "Good leadership springs from a genuine passion for the work and a genuine concern for other people. Great Leaders are people who love what they do and want to share that love with others. " (Daft, 2005:20). During an informal discussion with my husband Hugo Daniels, the leader in this Action Research Case Study, it became apparent that lawyers do not attend a single module or complete a single subject during their formal training at university to obtain their law degree that is related to the field of leadership and how to lead, inspire and motivate followers. The discussion centered on the problems the leader was experiencing in his East London law firm, problems he believed to be as a result of his lack of knowledge in the field of leadership. And so this research project began. It was obvious from the start that to intervene in the firm in order to bring about change would need the participation of everyone in the firm. The first step towards facilitating change would be to change the leadership style of the director of the firm. He would be required to gain knowledge in the field of leadership and the effects that different leadership styles have on followers. At the same time staff's perception of the current leadership style would have to be determined, as well as the desired style for their leader. The research process could then begin, based on the needs expressed by the staff and with participation from all levels in the firm. The case involved 27 members of staff made up of three heads of departments, twenty three general staff members and the leader. Data was gathered through formal interviews with the leader and the heads of departments, as well as from personal journals kept by two heads of departments and the leader. General staff members were first asked to complete The Productive Practice Survey (Hall 1987) to determine their perceptions of the current leadership style in the firm and what they thought they needed from their leader if the firm is to move forward. The Productive Practice Survey (Hall 1987) was not used with the intention of gathering quantitative data, but rather as a means of gathering information of staff's perception in general while ensuring anonymity, so as to facilitate a discussion during a feedback session. The Productive Survey's (Hall 1987) content and working is explained in further detail in Chapter 3 on page 44. Initially participants were skeptical of the process and used the survey as a medium to lash out against the firm and Hugo Daniels as a leader, leaving no room for suggestions for improvement, an "it is what it is" approach. During the feedback session general staff members became more open when they realized that change would benefit them, as changes would be suggested by them and implemented with their participation. They became less reluctant about change and provided valuable input during the session. All participants understood that this Participatory Action Research intervention was only the beginning of change in the firm and the sustainability of the changes rests on the firm as a whole, and working towards it would be a continuous process not ending with the Participatory Action Research process.
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  • Date Issued: 2008

Adaptive user interfaces for mobile map-based visualisation

  • Authors: Van Tonder, Bradley Paul
  • Date: 2008
  • Subjects: Cartography , Maps -- Design , Digital mapping , Geographic information systems , User interfaces (Computer systems) -- Design
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:10470 , http://hdl.handle.net/10948/866 , Cartography , Maps -- Design , Digital mapping , Geographic information systems , User interfaces (Computer systems) -- Design
  • Description: Mobile devices today frequently serve as platforms for the visualisation of map-based data. Despite the obvious advantages, mobile map-based visualisation (MMV) systems are often difficult to design and use. Limited screen space, resource constraints and awkward interaction mechanisms are among the many problems with which designers and users have to contend. Adaptive user interfaces (AUIs), which adapt to the individual user, represent a possible means of addressing the problems of MMV. Adaptive MMV systems are, however, generally designed in an ad-hoc fashion, making the benefits achieved difficult to replicate. In addition, existing models for adaptive MMV systems are either conceptual in nature or only address a subset of the possible input variables and adaptation effects. The primary objective of this research was to develop and evaluate an adaptive MMV system using a model-based approach. The Proteus Model was proposed to support the design of MMV systems which adapt in terms of information, visualisation and user interface in response to the user‟s behaviour, tasks and context. The Proteus Model describes the architectural, interface, data and algorithm design of an adaptive MMV system. A prototype adaptive MMV system, called MediaMaps, was designed and implemented based on the Proteus Model. MediaMaps allows users to capture, location-tag, organise and visualise multimedia on their mobile phones. Information adaptation is performed through the use of an algorithm to assist users in sorting media items into collections based on time and location. Visualisation adaptation is performed by adapting various parameters of the map-based visualisations according to user preferences. Interface adaptation is performed through the use of adaptive lists. An international field study of MediaMaps was conducted in which participants were required to use MediaMaps on their personal mobile phones for a period of three weeks. The results of the field study showed that high levels of accuracy were achieved by both the information and interface adaptations. High levels of user satisfaction were reported, with participants rating all three forms of adaptation as highly useful. The successful implementation of MediaMaps provides practical evidence that the model-based design of adaptive MMV systems is feasible. The positive results of the field study clearly show that the adaptations implemented were highly accurate and that participants found these adaptations to be useful, usable and easy to understand. This research thus provides empirical evidence that the use of AUIs can provide significant benefits for the visualisation of map-based information on mobile devices.
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  • Date Issued: 2008

Addressing the barriers to learning in the Helenvale area of Port Elizabeth : a school management perspective

  • Authors: Van Heerden, Edward Thomas
  • Date: 2008
  • Subjects: Students -- South Africa -- Port Alizabeth -- Social conditions , Children with social disabilities -- Education -- South Africa -- Port Elizabeth , Learning disabilities -- South Africa , School management and organization -- South Africa -- Port Elizabeth
  • Language: English
  • Type: Thesis , Masters , MEd
  • Identifier: vital:9544 , http://hdl.handle.net/10948/676 , Students -- South Africa -- Port Alizabeth -- Social conditions , Children with social disabilities -- Education -- South Africa -- Port Elizabeth , Learning disabilities -- South Africa , School management and organization -- South Africa -- Port Elizabeth
  • Description: Educational underachievement is a big problem in all schools, but it is especially prevalent in poverty stricken areas. The main objective of this research was to investigate the possible reasons for, consequences of and strategies to address the problem of educational underachievement in poverty stricken areas. The research conducted was based on the interpretive paradigm and a qualitative approach was used to gather data. A case study approach was used as a research design. The data collection methods were questionnaires, interviews and observations. The study found that the home conditions, individual factors, family and psychological factors are the main reasons for academic underachievement. The main consequences of academic underachievement were found to be unemployment, behavioural problems, a negative self-perception, high failure rates, high drop-out rates and teenage pregnancies. The main strategies to address the problem which the study revealed are: teachers familiarising themselves with the home conditions of the child, addressing the problem of overcrowding, and poverty, involving the parents in the education of their children, enhancing the self-esteem of learners, improving teaching, implementing cooperative learning and providing study facilities for these learners at the school after hours.
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  • Date Issued: 2008

Adoption of business information systems in an automotive manufacturing environment: a case study

  • Authors: Dyer, Shirley
  • Date: 2008
  • Subjects: Management information systems , Technology -- Information services , Information resources management , Business -- Data processing
  • Language: English
  • Type: Thesis , Masters , MTech
  • Identifier: vital:9772 , http://hdl.handle.net/10948/892 , Management information systems , Technology -- Information services , Information resources management , Business -- Data processing
  • Description: Dorbyl Automotive Technologies (DAT) is a manufacturing company that supplies parts and components to the local and international motor vehicle market. The automotive components’ market is very competitive and customers require more from the industry to stay competitive. Customers require full integration throughout the supply chain. DAT and its Information Systems Department have ensured that the necessary business information systems are available to assist the company in staying competitive. One problem, though, is that the users of these systems are not using and adopting the technologies available. This research examines the reasons for this by making use of a technology acceptance model called the UNIFIED THEORY OF ACCEPTANCE AND USE OF TECHNOLOGY (UTAUT), which is an integrated model based on eight different available acceptance models. The aim is to understand which factors influence the use of systems. The research also proposes a way forward by suggesting a model to assist DAT in new system implementations as well as correcting the current situation. The only way DAT will stay competitive is by ensuring that the company becomes lean. Customers demand this as more and more are moving to just-in-time delivery. This implies that the suppliers must react to changes real-time. The use of business information systems will become the main focus area to react to changes quickly and correctly. Effective and accurate systems depend on users making good use of these systems. Remaining competitive will depend on how effectively Information and Communication Technologies (ICT) are used.
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  • Date Issued: 2008

Adsorption of 4-nitrophenol onto Amberlite® IRA-900 modified with metallophthalocyanines

  • Authors: Marais, Eloïse , Nyokong, Tebello
  • Date: 2008
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/268576 , vital:54211 , xlink:href="https://doi.org/10.1016/j.jhazmat.2007.06.096"
  • Description: The adsorption of 4-nitrophenol using commercially available Amberlite® IRA-900 modified with metal phthalocyanines (MPc) was investigated. The metallophthalocyanines immobilised onto the surface of Amberlite® IRA-900 include Fe (FePcS4), Co (CoPcS4) and Ni (NiPcS4) tetrasulphophthalocyanines, and differently sulphonated phthalocyanine mixtures of Fe (FePcSmix), Co (CoPcSmix) and Ni (NiPcSmix). Adsorption rates were fastest for the modified adsorbents at a loading of 1 × 10−3 g MPc/g Amberlite, at pH 9. The highest amount of 4-NP removal was obtained on FePcSmix modified Amberlite® IRA-900 with Qt = 42.9 mmol g−1 and adsorption efficiency of 86%. The recovery efficiency of 4-NP within 150 min was 76%. Using the Langmuir–Hinshelwood kinetic model, the complexes showed an order of 4-nitrophenol adsorption to be as follows: CoPcSmix > NiPcS4 > NiPcSmix > FePcS4 > FePcSmix > CoPcS4. The MPc modified Amberlite® IRA-900 was used repeatedly, following removal of 4-NP by nitric acid, without any significant loss of activity.
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  • Date Issued: 2008

Agathis bishopi (Nixon) (Hymenoptera: braconidae) its biology and usefulness as a biological control agent for false codling moth (FCM), Thaumatotibia leucotreta (Meyrick) (Lepidoptera: tortricidae), on citrus bishopi (Nixon) (Hymenoptera: braconidae) its biology and usefulness as a biological control agent for false codling moth (FCM), Thaumatotibia leucotreta (Meyrick) (Lepidoptera: tortricidae), on citrus

  • Authors: Gendall, Kierryn Leigh
  • Date: 2008
  • Subjects: Cryptophlebia leucotreta -- Parasites , Cryptophlebia leucotreta -- Control , Pests -- Biological control , Tortricidae , Braconidae , Citrus -- Diseases and pests
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:5635 , http://hdl.handle.net/10962/d1005317 , Cryptophlebia leucotreta -- Parasites , Cryptophlebia leucotreta -- Control , Pests -- Biological control , Tortricidae , Braconidae , Citrus -- Diseases and pests
  • Description: The false codling moth, Thaumatotibia leucotreta (Meyrick) (Lepidoptera: Tortricidae), is one of the major pests of citrus in South Africa, the others being mealybug, Mediterranean fruit fly, bollworm and some mites. Due to problems such as the expense of pesticides, insects evolving pesticide resistance (Hogsette 1999), chemical residue on the skin of export fruit and the negative impact of pesticides on the environment, it became necessary to find alternative methods for pest control (Viggiani 2000). Agathis bishopi (Nixon) (Hymenoptera: Braconidae), a larval parasitoid of false codling moth known only from the Sundays River Valley area (Sishuba 2003), offers a means of control for the pest. A total of 11 389 navel oranges were collected from various orchards in the Addo/Kirkwood area, and false codling moth larvae infested 36.09% of the fruit. A single parasitoid species, A. bishopi, was reared from these larvae. In 2006 the highest parasitism rate, 11.43%, was recorded in May and in 2007, the highest parasitism rate, 13.27%, was in April. Agathis bishopi parasitizes larvae in instars 2 and 3, possibly due to the accessibility of these younger instars to the female parasitoid and possibly due to the length of the life cycle of this koinobiont. Second instar hosts yielded the highest number of parasitoids, and there was no emergence of parasitoids from fifth instar larvae. Females of A. bishopi live for 18.5 days (n = 20; S.E. = 3.1) and males for 8.25 days (n = 20; S.E. = 1.23). Females produce an average of 23 offspring in a lifetime, while female false codling moths produce about 800 eggs each. A high number of parasitoids will be required per hectare to reduce the population of false codling moth. Captive rearing of A. bishopi proved difficult due to viral and fungal contamination. Agathis bishopi has potential for use in an integrated pest management programme once the hurdle of mass-rearing has been overcome.
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  • Date Issued: 2008

Alternative products in the inhibition of te plant pathogen scleroyinia sclerotiorum on potato production

  • Authors: Dhliwayo, Tererayi
  • Date: 2008
  • Subjects: Potatoes -- Diseases and pests
  • Language: English
  • Type: Thesis , Masters , MTech
  • Identifier: vital:10587 , http://hdl.handle.net/10948/941 , Potatoes -- Diseases and pests
  • Description: White mold caused by Sclerotinia sclerotiorum attacks a wide host range of broad-leafed plants which includes potatoes. Current control is limited to the use of chemicals, but biological control has emerged as an eco-friendly alternative. For the study, 19 bacterial strains and 18 fungal strains obtained from soil samples taken from a potato field naturally infested with the pathogen S. sclerotiorum were tested for the effects on S. sclerotiorum mycelium growth and sclerotia viability in vitro. A total of eight bacterial strains and six fungal strains proved to be effective in the inhibition of S. sclerotiorum mycelium growth on PDA plate using a dual culture technique. These antagonistic microbes were six Bacillus subtilis, Bacillus pumilis, Bacillus marisflavi, Fusarium solani, Fusarium equiseti, Fusarium chlamydosporum, Aspergillus niger, Aspergillus insuetus and Penicillium citrinum. There was a significant difference (p<0.05) in the interaction between S. sclerotiorum mycelium growth and the time after inoculation with a S. sclerotiorum mycelium plug for both bacterial and fungal soil isolates. An additional sclerotia viability test was carried out using four of the eight antagonistic bacteria, and six of the antagonistic fungi. The results showed that two Bacillus species, namely B. pumilis and B. marisflavi can effectively reduce sclerotia viability. The other two bacteria (both B. subtilis), recorded low percentage reduction in sclerotia viability. As for the six antagonistic fungi, the viability test proved to be less effective in determining sclerotia viability. However, the result of this study supports the use of bio-control agents, not only because they are environmentally friendly, but because they are also an effective way of controlling the plant pathogen, S. sclerotiorum.
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  • Date Issued: 2008

An adaptive approach for optimized opportunistic routing over Delay Tolerant Mobile Ad hoc Networks

  • Authors: Zhao, Xiaogeng
  • Date: 2008
  • Subjects: Ad hoc networks (Computer networks) Computer network architectures Computer networks Routing protocols (Computer network protocols)
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:4588 , http://hdl.handle.net/10962/d1004822
  • Description: This thesis presents a framework for investigating opportunistic routing in Delay Tolerant Mobile Ad hoc Networks (DTMANETs), and introduces the concept of an Opportunistic Confidence Index (OCI). The OCI enables multiple opportunistic routing protocols to be applied as an adaptive group to improve DTMANET routing reliability, performance, and efficiency. The DTMANET is a recently acknowledged networkarchitecture, which is designed to address the challenging and marginal environments created by adaptive, mobile, and unreliable network node presence. Because of its ad hoc and autonomic nature, routing in a DTMANET is a very challenging problem. The design of routing protocols in such environments, which ensure a high percentage delivery rate (reliability), achieve a reasonable delivery time (performance), and at the same time maintain an acceptable communication overhead (efficiency), is of fundamental consequence to the usefulness of DTMANETs. In recent years, a number of investigations into DTMANET routing have been conducted, resulting in the emergence of a class of routing known as opportunistic routing protocols. Current research into opportunistic routing has exposed opportunities for positive impacts on DTMANET routing. To date, most investigations have concentrated upon one or other of the quality metrics of reliability, performance, or efficiency, while some approaches have pursued a balance of these metrics through assumptions of a high level of global knowledge and/or uniform mobile device behaviours. No prior research that we are aware of has studied the connection between multiple opportunistic elements and their influences upon one another, and none has demonstrated the possibility of modelling and using multiple different opportunistic elements as an adaptive group to aid the routing process in a DTMANET. This thesis investigates OCI opportunities and their viability through the design of an extensible simulation environment, which makes use of methods and techniques such as abstract modelling, opportunistic element simplification and isolation, random attribute generation and assignment, localized knowledge sharing, automated scenario generation, intelligent weight assignment and/or opportunistic element permutation. These methods and techniques are incorporated at both data acquisition and analysis phases. Our results show a significant improvement in all three metric categories. In one of the most applicable scenarios tested, OCI yielded a 31.05% message delivery increase (reliability improvement), 22.18% message delivery time reduction (performance improvement), and 73.64% routing depth decrement (efficiency improvement). We are able to conclude that the OCI approach is feasible across a range of scenarios, and that the use of multiple opportunistic elements to aid decision-making processes in DTMANET environments has value.
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  • Date Issued: 2008

An adaptive user interface model for contact centres

  • Authors: Jason, Bronwin Anastasia
  • Date: 2008
  • Subjects: Call centers -- Management , Customer services -- Management , Call centers -- Customer services
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:10467 , http://hdl.handle.net/10948/989 , Call centers -- Management , Customer services -- Management , Call centers -- Customer services
  • Description: Contact centres (CC), are the primary interaction point between a company and its customers and these are rapidly expanding in terms of both workforce and economic scope. An important challenge for today's CC solutions is to increase the speed at which CCAs retrieve information to answer customer queries. CCAs, however, differ in their ability to respond to these queries and do not interact with the computer user interface (UI) in the same way as they each have different capabilities, experience and expertise. Studies have provided empirical support that user performance can be increased when the computer UI characteristics match the user skill level. Adaptive user interfaces (AUIs) are the key to creating personalised systems. Their sole task is to provide an interface most suitable to users' needs whilst facilitating the users' varying skill levels. The aim of this research was to develop an AUI model for CCs to support and improve the expertise level of CCAs. A literature review of CCs, user expertise, AUIs and existing AUI models resulted in the proposal of an AUI model for CCs. The proposed AUI model was described in terms of its architecture, component-level and interface design. An AUI prototype was developed as a proof-of-concept of the proposed AUI model. A literature review on existing AUI evaluation approaches resulted in an evaluation strategy for the proposed AUI model. The AUI prototype was evaluated according to the evaluation strategy that was identified. User testing incorporating eye-tracking and a post-test questionnaire was used to determine the usefulness and usability of the AUI prototype. Significant results were found with regards to user satisfaction ratings, the learnability of the AUI prototype and its effectiveness. This dissertation makes an important contribution in the design of an AUI model that supports and improves the expertise level of CCAs. The model could be used to assist the development of CC applications incorporating AUIs. Future research is however needed to evaluate the effect of the proposed AUI model in a larger CC environment.
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  • Date Issued: 2008

An analysis of current East African higher education systems and institutions

  • Authors: Gouws, Jeanine
  • Date: 2008
  • Subjects: Education, Higher -- Africa, East -- Evaluation , Universities and colleges -- Africa, East
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:16147 , http://hdl.handle.net/10948/785 , Education, Higher -- Africa, East -- Evaluation , Universities and colleges -- Africa, East
  • Description: Higher education (HE) institutions play a vital role in the generation of new knowledge in the 21st Century, as HE is recognised as a key force for modernisation and development. The development and advancement of information technology have led to an interconnected, borderless world of knowledge, and HE institutions have become part of what is known as the global HE network society. HE institutions in developed countries are the most actively involved in producing and disseminating knowledge, and compete with one another in adding to this world stock of knowledge. In addition, HE has become a national priority in developed countries, and governments place pressure on HE institutions to form part of and remain active in the global HE network society in order to contribute to the knowledge-centred economy of today. However, the developing world lags far behind in becoming part of the global HE network society. As long as the developing world face constraints in attempts to improve national economies, alleviate poverty and maintain sustainability, prospects of contributing to, and participating in the global HE network society seem unlikely. HE can be used as a tool in addressing national development needs. With the necessary support and recognition from governments, HE should play a vital role in the process of reform and the revitalisation of developing countries. Africa is the least developed in terms of HE institutions. Approximately 300 institutions fit the definition of a university across the continent. While some countries on the continent, especially in Southern and Northern Africa, can claim comprehensive academic systems, most have just a few academic institutions and some countries have not yet even established differentiated post-secondary systems. It is generally assumed that most countries south of the Sahara lack adequate HE systems, or that they have no HE systems at all. Very little information on African HE systems and institutions, and how they function, is available, and there is a need for a deeper investigation into African HE systems and institutions. The vastness and diversity of the African continent does not allow for a single study of all African countries and their HE systems and institutions. It is for this reason that East Africa, comprising Kenya, Uganda and Tanzania, was chosen for this study. This specific region exhibits common characteristics amongst its countries. A British colonial history, similar secondary schooling systems and a predominance of the English language, set East Africa apart from the rest of the African continent. East African HE functions on a regional, national, and institutional level, and their way of functioning is interdependent.
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  • Date Issued: 2008

An analysis of exchange rate pass-through to prices in South Africa

  • Authors: Karoro, Tapiwa Daniel
  • Date: 2008
  • Subjects: Foreign exchange rates -- South Africa , Monetary policy -- South Africa , Inflation (Finance) -- South Africa , Prices -- South Africa , Banks and banking -- South Africa , South Africa -- Economic policy
  • Language: English
  • Type: Thesis , Masters , MCom
  • Identifier: vital:953 , http://hdl.handle.net/10962/d1002687 , Foreign exchange rates -- South Africa , Monetary policy -- South Africa , Inflation (Finance) -- South Africa , Prices -- South Africa , Banks and banking -- South Africa , South Africa -- Economic policy
  • Description: The fact that South Africa has a floating exchange rate policy as well as an open trade policy leaves the country’s import, producer and consumer prices susceptible to the effects of exchange rate movements. Given the central role that inflation targeting occupies in South Africa’s monetary policy, it becomes necessary to determine the nature of influence of exchange rate changes on domestic prices. To this end, this thesis examines the magnitude and speed of exchange rate pass-through (ERPT) to import, producer and consumer prices in South Africa. Furthermore, it explores whether the direction and size of changes in the exchange rate have different pass-through effects on import prices, that is, whether the exchange rate pass-through is symmetric or asymmetric. The paper uses monthly data covering the period January 1980 to December 2005. In investigating ERPT, two main stages are identified. The initial stage is the transmission of fluctuations in the exchange rate to import prices, while the second-stage entails the pass-through of changes in import prices to producer and consumer prices. The first stage is estimated using the Johansen (1991) and (1995) cointegration techniques and a vector error correction model (VECM). The second stage pass-through is determined by estimating impulse response and variance decomposition functions, as well as conducting block exogeneity Wald tests. The study follows Wickremasinghe and Silvapulle’s (2004) approach in estimating pass-through asymmetry with respect to appreciations and depreciations. In addition, the thesis adapts the analytical framework of Wickremasinghe and Silvapulle (2004) to investigate the pass-through of large and small changes in the exchange rate to import prices. The results suggest that ERPT in South Africa is incomplete but relatively high. Furthermore, ERPT is found to be higher in periods of rand depreciation than appreciation which supports the binding quantity constraint theory. There is also some evidence that pass-through is higher in periods of small changes than large changes in the exchange rate, which supports the menu cost theory when invoices are denominated in the exporters’ currency.
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  • Date Issued: 2008

An analysis of factors affecting housing delivery in the Nyandeni local municipality with specific reference to the Extension 4 Housing Project: a case study of Ward 21 in Ngqeleni

  • Authors: Madzidzela, Liyanda
  • Date: 2008
  • Subjects: Housing policy -- South Africa , Low-income housing -- South Africa -- Eastern Cape , Public housing -- South Africa -- Eastern Cape , Housing development -- South Africa , Community development, Urban -- South Africa -- Eastern Cape
  • Language: English
  • Type: Thesis , Masters , MPA
  • Identifier: vital:8219 , http://hdl.handle.net/10948/1004 , Housing policy -- South Africa , Low-income housing -- South Africa -- Eastern Cape , Public housing -- South Africa -- Eastern Cape , Housing development -- South Africa , Community development, Urban -- South Africa -- Eastern Cape
  • Description: The study investigates problems and challenges that, the Nyandeni local municipality faces in terms of housing delivery to its communities. The purpose is to look at the factors that affect housing delivery at Nyandeni local municipality in the Extension 4 Housing Project in Ngqeleni and what can be done in order to improve it. The housing development at Nyandeni Local Municipality is not up to standard, the situation is worse in rural areas where there is not a single rural housing project that has been implemented thus far instead, there is a lack of infrastructure and other essential services. This is a serious problem that the Nyandeni local municipality faces, as a result the most vulnerable people are the poorest of the poor particularly those residing in rural areas. The study has investigated housing delivery at Nyandeni local municipality with reference to the Extension 4 Housing Project in Ngqeleni. The investigation indicates that there are serious challenges facing housing delivery. Hence the beneficiaries of the project could not get their houses in time and the project could not be completed within the scheduled period.
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  • Date Issued: 2008

An analysis of local level development in South Africa: a case study of Uitenhage

  • Authors: Meyer, Sarah
  • Date: 2008
  • Subjects: Local government -- South Africa -- Uitenhage -- Case studies Economic development -- South Africa -- Case studies Municipal corporations -- South Africa -- Case studies Community development -- South Africa -- Case studies Cities and towns -- South Africa -- Case studies Social responsibility of business -- South Africa Small business -- South Africa
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:4813 , http://hdl.handle.net/10962/d1005487
  • Description: Development backlogs, in terms of unemployment and poverty, plague many developing countries. Countries have established and implemented various policies and plans to address these challenges. In response to these development backlogs, South Africa has instituted the notion of decentralisation and developmental local government, whereby local governments are largely responsible for initiating and facilitating development in the area under their jurisdiction. Furthermore, the potential role the private sector can play in development is being increasingly recognised by government, politicians, academics and developers alike. Uitenhage has a strong corporate presence and therefore this sector has the potential to contribute towards development in the town. However the concept of using corporate social responsibility (CSR) to promote development in South Africa is relatively new and, as will be revealed in the case study, definitions and underlying motivation for undertaking CSR vary. Local Economic Development (LED) and, more recently, CSR, have been recognised as major drivers of development and are being implemented throughout the country. As this thesis illustrates, they often merge and can work hand-in-hand to promote local development. Although the private sector, through CSR has the potential to contribute to development, they often do not have the available human resources to implement development initiatives. As is evident in the case study, partnerships between the private and public sectors often emerge as a result. Development institutions play a key role in development and often assist in bridging the gap between citizens, the state and the market. The development institutions in Uitenhage often act as instigators and facilitators on behalf of the larger corporations. The case study in Uitenhage, is a locality where there is a strong automotive industrial cluster and several major firms which are active in the development process. Furthermore, development institutions are committed to the socio-economic development of the town and the promotion of small micro medium enterprises (SMMEs), through various support services. The development institutions, often in partnership with the local government and the public sector, have initiated various local developmental projects in the town, of which three will be discussed in the case study. In this thesis, case study research reveals that corporations often do not meet their potential developmental role and their CSR actions are often considered as ‘window-dressing’ aimed at boosting their corporate image. Similarly, with regard to the development institutions, their development and job creation results look impressive at first glance, but further investigation reveals a collapse of a large number of projects. Despite the potential of LED and CSR to be major drivers of local development, there are still a number of hindering factors, which will be revealed in this thesis and lessons to be learnt which can help to inform future local development projects
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  • Date Issued: 2008

An analysis of strategies used to manage conflict at Volkswagen of South Africa

  • Authors: Conybeare, Gaily
  • Date: 2008
  • Subjects: Volkswagen of South Africa (Firm) , Conflict management -- South Africa , Motor vehicle industry -- South Africa -- Port Elizabeth
  • Language: English
  • Type: Thesis , Masters , MBA
  • Identifier: vital:8743 , http://hdl.handle.net/10948/762 , Volkswagen of South Africa (Firm) , Conflict management -- South Africa , Motor vehicle industry -- South Africa -- Port Elizabeth
  • Description: This research study addresses the problem of determining the strategies that can be used by Internal Audit at Volkswagen of South Africa to manage conflict effectively. To achieve this objective a comprehensive literature study was performed to determine the views on conflict and evaluate the various conflict models. The study also included the reasons for and sources of conflict and the effects of conflict on the performance and controls within VWSA. The identification of conflict management strategies and subsequent conflict management styles were revealed by the literature study. Various discussions from different authors on how to resolve conflict situations are also discussed. The literature review serves as a model in the development of a guideline for VWSA Internal Audit team and management to manage conflict. Senior Management, middle management and staff from various departments within VWSA were requested to complete a questionnaire in order to determine the strategies and effectiveness of these strategies used by Internal Audit to manage conflict. The questionnaire was developed in accordance with the findings from the research. A pilot study was conducted to evaluate the relevance of the study to the problem questions and to evaluate whether the questionnaire will be easily understood. The answers of the respondents were analyzed and compared to the findings of the literature study. The information obtained from the literature study and from the respondents resulted in various recommendations and conclusions.
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  • Date Issued: 2008

An analysis of the implementation of sustainability principles in Buffalo City Municipality

  • Authors: Mniki, Phumzile
  • Date: 2008
  • Subjects: Buffalo City (South Africa) Local government -- South Africa -- Eastern Cape -- Case studies Municipal government -- South Africa -- Eastern Cape -- Case studies Sustainable development -- South Africa -- Eastern Cape -- Case studies Strategic planning -- South Africa -- Eastern Cape -- Case studies Economic development -- South Africa -- Eastern Cape -- Case studies
  • Language: English
  • Type: Thesis , Masters , MBA
  • Identifier: vital:790 , http://hdl.handle.net/10962/d1003941
  • Description: This study investigated the planning, implementation and monitoring of sustainability principles in Buffalo City Municipality (BCM), in the Eastern Cape Province. It also analysed how reporting on sustainability principles was done at this municipality. The research was conducted as a qualitative case study that used analyses of documents, questionnaires and interviews to gather data. All respondents were involved with BCM, some as municipal officials in key positions in the different directorates and others as councillors. The study was contextualised within the area of sustainable development at local government level. The focus was on how the mandate of sustainable local development at local government level was met in BCM. The focus was on the planning, implementation and monitoring of stipulations of Local Agenda 21 and sustainability principles. The study focused on the provision of basic services; inter-generational equity; integration of economic, social and environmental aspects; community involvement; institutional capacity building; partnerships, and global links. The study established that Buffalo City Municipality incorporated sustainability in its vision. There was a lack of common understanding of the meaning of sustainability. Sustainability principles featured prominently at the integrated development planning phase but were less explicitly mentioned in the implementation, monitoring and reporting phases. Sustainability principles were subsumed in the developmental goals of the municipality. The study also highlighted the need for a strategy to have an institution-wide implementation of sustainability principles which would incorporate raising awareness about sustainability and its value.
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  • Date Issued: 2008

An analysis of the influence of question design on pupils' approaches to number pattern generalisation tasks

  • Authors: Samson, Duncan Alistair
  • Date: 2008
  • Subjects: Mathematics -- Study and teaching Number theory -- Problems, exercises, etc Algebra -- Study and teaching Arithmetic -- Foundations Pattern perception
  • Language: English
  • Type: Thesis , Masters , MEd
  • Identifier: vital:1421 , http://hdl.handle.net/10962/d1003302
  • Description: This study is based on a qualitative investigation framed within an interpretive paradigm, and aims to investigate the extent to which question design affects the solution strategies adopted by children when solving linear number pattern generalisation tasks presented in pictorial and numeric contexts. The research tool comprised a series of 22 pencil and paper exercises based on linear generalisation tasks set in both numeric and 2-dimensional pictorial contexts. The responses to these linear generalisation questions were classified by means of stage descriptors as well as stage modifiers. The method or strategy adopted was carefully analysed and classified into one of seven categories. A meta-analysis focused on the formula derived for the nth term in conjunction with its justification. The process of justification proved to be a critical factor in being able to accurately interpret the origin of the sub-structure evident in many of these responses. From a theoretical perspective, the central role of justification/proof within the context of this study is seen as communication of mathematical understanding, and the process of justification/proof proved to be highly successful in providing a window of understanding into each pupil’s cognitive reasoning. The results of this study strongly support the notion that question design can play a critical role in influencing pupils’ choice of strategy and level of attainment when solving pattern generalisation tasks. Furthermore, this study identified a diverse range of visually motivated strategies and mechanisms of visualisation. An awareness and appreciation for such a diversity of visualisation strategies, as well as an understanding of the importance of appropriate question design, has direct pedagogical application within the context of the mathematics classroom.
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  • Date Issued: 2008
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