The purpose of this study was to determine whether it has an effect on teachers’ resilience when they live according to their innate talents and strengths. The result of the Clifton StrengthsFinder® (CSF) assessment was used as the basis for this study. I linked Bandura’s social cognitive theory with the CSF and used it as a conceptual framework for the study. Bandura identified four core features of human agency, namely intentionality, forethought, self-reaction and self-reflection. The 34 talent themes identified by the CSF are divided into four domains, namely executional, thinking, influencing and relational. These four domains of talent themes can be partially linked with Bandura’s four core features of human agency. The domains of talent themes cannot be individually and rigidly linked with each of the features identified by Bandura, but there are clearly discernible points of contact between the talent themes and the core features of human agency. In this qualitative study I conducted conversational interviews with eight participants from a phenomenological perspective. Seven participants were female and one male. Five of the participants are educators at private schools; generally not well-resourced, but with small class groups. The other three participants are employed at former Model C schools with significantly more resources, but also much larger class groups. All the educators who participated in this study indicated that the outcome of the CSF assessment described them accurately. Most of the participants live and work according to their strengths and experience that it plays a significant role in their resilience at work. Participants who indicated that they do not live according to their strengths, or use it to a lesser extent, experience limited or no resilience professionally and personally. / Dissertation (Med)--University of Pretoria, 2017. / Humanities Education / MEd / Unrestricted

Masters in Public Administration - MPA / Plaaslike owerheidsaangeleenthede in Suid-Afrika het in die algemeen deurlopend heelwat aandag vanaf owerheidsweë geniet (cf. die talle verslae en bevindings van komitees van ondersoek na aangeleenthede rakende plaaslike bestuur sedert Uniewording in 1910). Hierdie proses is sedertdien voortgesit, maar vanaf 1994 het dit verdere momentum verkry met die nuwe grondwetlike bedeling wat tot stand gebring is. 'n Verskeidenheid van wetgewing het gevolg wat spesifiek op plaaslike owerhede van toepassing is. Die belangrikste hiervan is die Grondwet van die Republiek van Suid-Afrika, 1996; die Oorgangswet op Plaaslike Regering, 1993; Oorgangswet op Plaaslike Regering Tweede Wysigingswet, 1996; Wet op Ontwikkelingsfinansiering, 1995; Wet op Plaaslike Regering: Munisipale Strukture, 1998; Wet op Plaaslike Regering: Munisipale Stelsels, 2000; asook' die belangrike Witskrif op Plaaslike Regering van 1998. Hierdie verwikkelinge vestiq weer eens die aandag op die belangrikheid van instellings op die derde owerheidsvlak. Soos aanvanklik die geval was, is die oogmerk tans ook om onder andere werkverrigting en dienslewering te bevorder en effektiewe en doeltreffende aanwending van skaars hulpbronne te verseker. Hierdie aangeleentheid het veral momentum verkry met die Heropbou- en Ontwikkelingsprogram (HOP), wat in 'n groot mate op plaaslike oweheidsvlak afgestem is. Met die nuwe beleid van die sentrale regering om die huidige aantal plaaslike owerhede deur samesmelting ingrypend te verminder, maar hulle terselfdertyd te verplig om steeds voort te gaan met bestaande basiese dienslewering en om bykomend ook infrastruktuur vir voorheen benadeelde gemeenskappe te skep en in stand te hou sonder noemenswaardige verhoogde finansiële bystand vanaf sentrale owerheidsvlak, is plaaslike owerhede al hoe meer aangewese op eie hulpbronne. Plaaslike owerhede .gaan reeds gebuk onder ingrypende finansiële en personeeltekorte wat op sigself meebring dat diens van hoë gehalte nie te alle tye gelewer kan word nie (verwys in dié geval. na Sake Rapport, 16 Junie 2002: 18). Gepaard hiermee word plaaslike owerhede onder druk geplaas om aan die verwagtinge, behoeftes en aspirasies van die plaaslike samelewing te voldoen. Dit bring volgens Fourie (1998: 221) mee dat "ten einde 'n diens van uitnemendheid te lewer, is dit van belang dat die publiek se behoeftes begryp word, nastrewenswaardige doelwitte gestel word en dat die doelwitte aan die publiek gekommunikeer word". Daar is egter terselfdertyd ook 'n 2 verpligting op plaaslike owerhede om onrealistiese verwagtinge van die publiek te temper in die lig van wat werklik bekostigbaar is. Gevolglik word plaaslike owerhede verplig om weer eens hulomstandighede in oenskou te neem ten einde daadwerklik effektiewe en doeltreffende aanwending van skaars hulpbronne te verseker.' Resultate salook op 'n gereelde grondslag gemoniteer moet word ten einde vas te stelof doelwitte bereik is al dan nie (Fourie, 1998: 221). Hiervoor sal kundigheid op plaaslike owerheidsvlak ontwikkel moet word ten einde die bevordering van die algemene welsyn van plaaslike gemeenskappe te verseker. Persone met die nodige kwalifikasies en vaardighede sal dus in sleutelposte aangestel moet word.

New and proposed tax relief sections have been added to the Income Tax Act no 58 of 1962 over the past few years and this is an indication that the South African (SA) Government acknowledges that there is considerable investment required, by both SA taxpayers and the SA Government, to go “green” and to save energy. The National Treasury proposed the introduction of section 12L to the Income Tax Act No 58 of 1962 (the Act) in the 2009 Taxation Laws Amendment Act. This will provide an incentive for taxpayers to benefit from energy savings by incurring capital expenditure with the purpose of reducing energy consumption. The idea with the proposed section 12L is that the more energy one saves, the less tax one pays. However, the proposed introduction of section 12L has led to uncertainty as to the process to be followed by a taxpayer, in order to qualify for the allowance. There will be a discussion on whether this notional allowance will be in addition to the allowances and deductions based on actual expenditure incurred in the investment of new green technologies. The objective during the current study is to examine how government should formulate SA legislation in terms of section 12L of the Act to stimulate investment in the conversion of old technologies to new “green” technology. The challenges of improved energy savings will be addressed in the SA context, and compared to similar legislation in China and the United Kingdom (UK). This comparison will identify the gaps, alternatives and possible improvements to the proposed SA section 12L. AFRIKAANS : Nuwe en voorgestelde wetsartikels vir die vermindering van belasting is gedurende die laaste paar jaar ingedien. Dit is ’n aanduiding dat die Suid-Afrikaanse (SA) Regering erken dat aansienlike belegging benodig word om “groen” te raak en om krag te bespaar. Die Nasionale Tesourie het die indiening van artikel 12L in die Inkomste belasting Wet Nr. 58 van 1962 (Die Wet) in die 2009 Belasting Wysigingswet voorgestel. Dit sal as aansporing dien vir belastingbetalers om voordeel te trek uit energiebesparing deur om kapitaaluitgawes wat lei tot die vermindering van kragverbruik aan te gaan. Die idée agter die voorgestelde artikel 12L is dat hoe meer energie ’n mens spaar, hoe minder belasting jy hoef te betaal. Die voorgestelde indiening van wetsartikel 12L lei egter tot onsekerheid oor die proses wat die belatingbetaler moet volg om vir die toelaag te kwalifiseer. Die bespreking sal insluit of hierdie voorgestelde toelaag bykomend sal wees tot die toelae en aftrekkings wat gegrond is op werklike uitgawes wat aangegaan is tydens belegging in die nuwe groen tegnologie. Die doelwit met hierdie studie is om ondersoek in te stel in hoe die regering die SA wetgewing in terme van artikel 12L van die belastingwet moet formuleer om sodoende belegging in die omskakeling van die ou tegnologie na die nuwe “groen” tegnologie te stimuleer. Die uitdaging van energie besparing sal in die SA konteks aangespreek word en vergelyk word met soortgelyke wetgewing in die Verenigde Koningkryk (VK) en China. Die gapings, alternatiewe en moontlike verbeterings in die voorgestelde wetsartikel 12L sal tydens hierdie vergelyking identifiseer word. Copyright 2011, University of Pretoria. All rights reserved. The copyright in this work vests in the University of Pretoria. No part of this work may be reproduced or transmitted in any form or by any means, without the prior written permission of the University of Pretoria. Please cite as follows: Du Toit, EF 2011, Energy efficiency savings allowance in South Africa : an international comparison, MCom dissertation, University of Pretoria, Pretoria, viewed yymmdd < http://upetd.up.ac.za/thesis/available/etd-03062012-113449 / > F12/4/146/gm / Dissertation (MCom)--University of Pretoria, 2012. / Taxation / unrestricted

The progression of skin ageing in individuals is multifaceted and provoked by various aspects, including hereditary and a variety of environmental causes, for instance UV (ultra violet) radiation, resulting in the morphological modifications in the dermal layer of the skin (Makrantonaki & Zouboulis, 2007:40) Transformations caused by ageing skin, in which degenerative alterations exceed regenerative alterations are recognised by the thinning and wrinkling of the epidermis in conjunction with the appearance of lines, creases, crevices and furrows, particularly emphasised in lines of facial expressions (Aburjai & Natsheh, 2003:990). For human beings to continue to exist in a terrestrial atmosphere, the loss of water from the skin must be cautiously synchronised by the epidermis, a task dependent on the multifaceted character of the stratum corneum (Rawlings & Harding, 2004:43). The stratum corneum (SC) is responsible for the main resistance to the penetration of most compounds; nevertheless the skin represents as an appropriate target for delivery. The target site for anti-ageing treatment includes the epidermal and dermal layers of the skin. Therefore, the need to apply fatty materials to the skin is practically intuitive and may perhaps be as old as man’s existence itself (Lodén, 2005:672). Natural therapies have been used for several decades for taking care of skin illnesses and a wide variety of dermatological disorders, such as inflammation, phototoxicity, atopic dermatitis and alopecia areata (Aburjai & Natsheh, 2003:988). Using the skin as an alternative route for the administration of honeybush extracts for the treatment of ageing skin may be beneficial. Tea contains more than 500 chemical compounds, including, tannins, flavonoids, amino acids, vitamins, caffeine and polysaccharides. Tea polyphenols (flavonoids) have proven anti-inflammatory, antioxidant, antiallergic, antibacterial and antiviral effects (Aburjai & Natsheh, 2003:990). Unfortunately using the skin as an alternative route for administering drugs (transdermal drug delivery) has numerous limitations. One of these limitations is the barrier function of the skin (Naik et al., 2000:319). Because of the skin’s outstanding ability to protect the body against unwanted substances from its surroundings, it is necessary to use methods to enhance drug penetration through the skin. The aim of this study was to formulate two 2% semisolid formulations containing two different honeybush extracts as the active ingredient, and to determine which of the formulations deliver mangiferin and hesperidin best to the target site (dermis). Cosmetic formulations of a natural origin, is designed to protect the skin against exogenous or endogenous harmful agents, as well as to balance the dermal homeostatis lipids altered by dermatosis and ageing (Aburjai & Natsheh, 2003:988). Stability tests over a three month period were also performed on the different formulations. To determine the stability of the different semi-solid formulations, the formulated products were stored at 25 °C/60% RH (relative humidity), 30 °C/60% RH and 40 °C/75% RH. HPLC analysis was used to determine the concentrations of the ingredients in all the formulated products. Other stability tests included appearance, pH, viscosity, mass loss, zeta potential and particle size determination. Unfortunately a change in colour, viscosity, zeta potential, mass loss, particle size and concentration of the ingredients in both the formulations, indicated that the products were unstable from the first month of stability testing. A 2% Cyclopia maculata cream as well as a 2% Cyclopia genistoides cream was formulated. Franz cell diffusion studies as well as membrane release studies were performed over a 12 h period, followed by tape stripping experiments to determine which semi-solid formulation delivered mangiferin and hesperidin the best to the dermal layer of the skin. The results of the different formulations were compared. Unfortunately there was no significant penetration by any of the honeybush extracts. Results were inconclusive and unquantifiable due to unconvincing penetration results. The antioxidant properties of both the extracts and the active ingredients were calculated. Antioxidant studies by the use of the TBA-assay method were done to determine whether the honeybush extracts, mangiferin and hesperidin as well as their semisolid formulations had any antioxidant activities. Both the honeybush extracts and the semisolid formulations showed promising results. Mangiferin and hesperidin did not show any antioxidant activity on their own, therefore the assumption can be confirmed that plants do function synergistically. A clinical study was also conducted to see whether honeybush extracts have the potential to hydrate the skin, counteracting the symptoms and signs of skin ageing. Clinical efficacy studies were done to determine whether the honeybush formulations had any skin hydrating effects in the treatment against skin ageing. The results were statistically inconclusive and variations between the subjects were very high due to skin variations at different skin sites. There was however a trend that Cyclopia genistoides performed the best. / Thesis (MSc (Pharmaceutics))--North-West University, Potchefstroom Campus, 2013.

The energy provider in South Africa, Eskom, faces an increasing electricity demand. The need to ensure sufficient supply gave rise to Demand Side Management (DSM) projects scheme. The DSM focus has shifted to the mining sector in South Africa. The large electricity use of the mining sector ensured the need for Energy Services Companies (ESCo’s). The ESCo is contracted to ensure energy savings of DSM projects implemented within the multiple sectors such as mining industry. The mining sector business model has the constant pressure to increase gold production. This pressure to expand has led to rapid expansion plans to increase the gold output for the relevant company. The expansion process and production increase in turn increases the electricity consumption. Compressed air use is a large contributing factor to the monthly electricity use as it is widely used within the mine sector. The implementation of a DSM project on the compressed air ring of an expanding gold mine was the focus of the study. This case study focused on an expanding gold mine within South Africa. The DSM lifecycle was followed to initially determine the DSM saving potential. The possible control strategies were investigated with simulation models and savings calculations. The viable option was to be implemented with a preliminary control philosophy. Results were in turn compared with the initial investigations and control philosophy. The deviations as experienced with implementation were addressed and a potential sustainable control philosophy for an expanding gold mine was constructed. The results indicated, verified Eskom peak clip electricity savings of 2.165 MW of the 2.4 MW target. The energy efficiency component for these performance assessment months was 1.944 MW of the targeted 1.5 MW. The sustainability of the system was proven with production increase on an expanding gold mine. / MIng (Computer and Electronic Engineering), North-West University, Potchefstroom Campus, 2013

The progression of skin ageing in individuals is multifaceted and provoked by various aspects, including hereditary and a variety of environmental causes, for instance UV (ultra violet) radiation, resulting in the morphological modifications in the dermal layer of the skin (Makrantonaki & Zouboulis, 2007:40) Transformations caused by ageing skin, in which degenerative alterations exceed regenerative alterations are recognised by the thinning and wrinkling of the epidermis in conjunction with the appearance of lines, creases, crevices and furrows, particularly emphasised in lines of facial expressions (Aburjai & Natsheh, 2003:990). For human beings to continue to exist in a terrestrial atmosphere, the loss of water from the skin must be cautiously synchronised by the epidermis, a task dependent on the multifaceted character of the stratum corneum (Rawlings & Harding, 2004:43). The stratum corneum (SC) is responsible for the main resistance to the penetration of most compounds; nevertheless the skin represents as an appropriate target for delivery. The target site for anti-ageing treatment includes the epidermal and dermal layers of the skin. Therefore, the need to apply fatty materials to the skin is practically intuitive and may perhaps be as old as man’s existence itself (Lodén, 2005:672). Natural therapies have been used for several decades for taking care of skin illnesses and a wide variety of dermatological disorders, such as inflammation, phototoxicity, atopic dermatitis and alopecia areata (Aburjai & Natsheh, 2003:988). Using the skin as an alternative route for the administration of honeybush extracts for the treatment of ageing skin may be beneficial. Tea contains more than 500 chemical compounds, including, tannins, flavonoids, amino acids, vitamins, caffeine and polysaccharides. Tea polyphenols (flavonoids) have proven anti-inflammatory, antioxidant, antiallergic, antibacterial and antiviral effects (Aburjai & Natsheh, 2003:990). Unfortunately using the skin as an alternative route for administering drugs (transdermal drug delivery) has numerous limitations. One of these limitations is the barrier function of the skin (Naik et al., 2000:319). Because of the skin’s outstanding ability to protect the body against unwanted substances from its surroundings, it is necessary to use methods to enhance drug penetration through the skin. The aim of this study was to formulate two 2% semisolid formulations containing two different honeybush extracts as the active ingredient, and to determine which of the formulations deliver mangiferin and hesperidin best to the target site (dermis). Cosmetic formulations of a natural origin, is designed to protect the skin against exogenous or endogenous harmful agents, as well as to balance the dermal homeostatis lipids altered by dermatosis and ageing (Aburjai & Natsheh, 2003:988). Stability tests over a three month period were also performed on the different formulations. To determine the stability of the different semi-solid formulations, the formulated products were stored at 25 °C/60% RH (relative humidity), 30 °C/60% RH and 40 °C/75% RH. HPLC analysis was used to determine the concentrations of the ingredients in all the formulated products. Other stability tests included appearance, pH, viscosity, mass loss, zeta potential and particle size determination. Unfortunately a change in colour, viscosity, zeta potential, mass loss, particle size and concentration of the ingredients in both the formulations, indicated that the products were unstable from the first month of stability testing. A 2% Cyclopia maculata cream as well as a 2% Cyclopia genistoides cream was formulated. Franz cell diffusion studies as well as membrane release studies were performed over a 12 h period, followed by tape stripping experiments to determine which semi-solid formulation delivered mangiferin and hesperidin the best to the dermal layer of the skin. The results of the different formulations were compared. Unfortunately there was no significant penetration by any of the honeybush extracts. Results were inconclusive and unquantifiable due to unconvincing penetration results. The antioxidant properties of both the extracts and the active ingredients were calculated. Antioxidant studies by the use of the TBA-assay method were done to determine whether the honeybush extracts, mangiferin and hesperidin as well as their semisolid formulations had any antioxidant activities. Both the honeybush extracts and the semisolid formulations showed promising results. Mangiferin and hesperidin did not show any antioxidant activity on their own, therefore the assumption can be confirmed that plants do function synergistically. A clinical study was also conducted to see whether honeybush extracts have the potential to hydrate the skin, counteracting the symptoms and signs of skin ageing. Clinical efficacy studies were done to determine whether the honeybush formulations had any skin hydrating effects in the treatment against skin ageing. The results were statistically inconclusive and variations between the subjects were very high due to skin variations at different skin sites. There was however a trend that Cyclopia genistoides performed the best. / Thesis (MSc (Pharmaceutics))--North-West University, Potchefstroom Campus, 2013.

The energy provider in South Africa, Eskom, faces an increasing electricity demand. The need to ensure sufficient supply gave rise to Demand Side Management (DSM) projects scheme. The DSM focus has shifted to the mining sector in South Africa. The large electricity use of the mining sector ensured the need for Energy Services Companies (ESCo’s). The ESCo is contracted to ensure energy savings of DSM projects implemented within the multiple sectors such as mining industry. The mining sector business model has the constant pressure to increase gold production. This pressure to expand has led to rapid expansion plans to increase the gold output for the relevant company. The expansion process and production increase in turn increases the electricity consumption. Compressed air use is a large contributing factor to the monthly electricity use as it is widely used within the mine sector. The implementation of a DSM project on the compressed air ring of an expanding gold mine was the focus of the study. This case study focused on an expanding gold mine within South Africa. The DSM lifecycle was followed to initially determine the DSM saving potential. The possible control strategies were investigated with simulation models and savings calculations. The viable option was to be implemented with a preliminary control philosophy. Results were in turn compared with the initial investigations and control philosophy. The deviations as experienced with implementation were addressed and a potential sustainable control philosophy for an expanding gold mine was constructed. The results indicated, verified Eskom peak clip electricity savings of 2.165 MW of the 2.4 MW target. The energy efficiency component for these performance assessment months was 1.944 MW of the targeted 1.5 MW. The sustainability of the system was proven with production increase on an expanding gold mine. / MIng (Computer and Electronic Engineering), North-West University, Potchefstroom Campus, 2013

The main goal of this study was to evaluate whether three dimensional musculoskeletal modelling (3D) is effective in assessing the safety and efficacy of resistance training equipment. The focus of the evaluation was on the biomechanical and anthropometric considerations of the end-user. 3D musculoskeletal modelling was used to evaluate four pieces of resistance training equipment, namely the seated biceps curl, abdominal crunch, seated row and chest press. Three anthropometric cases were created; these represented a traditional 5th percentile female as well as a 50th and 95th percentile male based on body mass index (BMI). Resistance on the training machines was set at fifty percent of the functional strength one repetition maximum (1RM), for each anthropometric case and piece of exercise equipment two repetitions were performed except for the abdominal crunch model during which four repetitions were simulated. Each piece of equipment presented unique challenges. In three of the four studies (seated biceps curl, seated row and chest press) the default model created by the modelling software was not adequate to solve the forward dynamics simulations and thus adjustments had to be made to the default model in order to complete the modelling process. 3D musculoskeletal modelling by means of LifeModelerTM software was able to identify some potential risk for musculoskeletal injury as well as highlight the discrepancies between the anthropometric cases, specifically the accommodation of the 5th percentile female and the machines’ engineered adjustability. 3D musculoskeletal modelling has the potential to indicate shortcomings in resistance training equipment design. Therefore it appears as if 3D musculoskeletal modelling can be used to evaluate resistance training equipment design however the limitations as indicated by this study must be taken into consideration especially when using default models.AFRIKAANS: Die doel van die studie was om die effektiwiteit van driedimensionele (3D) muskuloskeletale modellering te evalueer in terme van die tegniek se vermoë om die veiligheid en doeltreffendheid van weerstands oefenapparaat te evalueer. Die fokus van die evaluasie was op die biomeganiese en antropometriese oorwegings van die end-gebruiker. 3D muskuloskeletale modellering was gebruik in die evaluasie van vier weerstands oefenapparate genaamd die sittende biceps krul, abdominale krul, sittende roei en sittende borsstoot. Drie antropometriese gevalle is geskep, die het ‘n tradisionele 5e persentiel vrou, sowel as ‘n 50ste en 95ste persentiel man voorgestel en was gebasseer op liggaamsmassa indeks waardes. Die eksterne weerstand van die apparaat was bepaal teen vyftig persent van die funsionele krag een-repetisie- maksimum vir elk van die antropometriese gevalle en twee repetisies is uitgevoer behalwe vir die abdominale krul waartydens vier repetisies gesimuleer is. Elke apparaat het unieke uitdagings gestel. In drie van die vier studies (sittende biceps krul, sittende roei en sittende borsstoot) was die standaard model van die sagteware onvoldoende om die voorwaards dinamiese simulasie op te los en moes aanpassings aan die modelle gemaak word vir suksesvolle simulasies. Die modellerings proses met die Lifemodeler™ sagteware kon potensiële risiko vir muskuloskeletale besering sowel as verskille tussen die verskeie antropometriese gevalle uitwys. Dit was veral opvallend vir die akkomodasie van die 5e persentiel vrou asook betreffende die apparaat se vervaardigde verstelbaarheid. 3D muskuloskeletale modellering beskik oor die vermoë om voorstelle vir verbetering in die ontwerp van weerstands oefenapparaat uit te wys. Dit blyk dus dat 3D muskuloskeletale modellering beslis gebruik kan word vir die evaluasie van weerstands oefenapparaat ontwerp, die beperkings van die studie moet egter in gedagte gehou word, veral wanneer standaard modelle gebruik word. / Thesis (DPhil)--University of Pretoria, 2011. / Biokinetics, Sport and Leisure Sciences / unrestricted

A wireless sensor network is a distributed network system consisting of miniature spatially distributed autonomous devices designed for using sensors to sense the environment and cooperatively perform a specific goal. Each sensor node contains a limited power source, a sensor and a radio through which it can communicate with other sensor nodes within its communication radius. Since these sensor nodes may be deployed in inaccessible terrains, it might not be possible to replace their power sources. The radio transceiver is the hardware component that uses the most power in a sensor node and the optimisation of this element is necessary to reduce the overall energy consumption. In the data link layer there are several major sources of energy waste which should be minimised to achieve greater energy efficiency: idle listening, overhearing, over-emitting, network signalling overhead, and collisions. Sleep scheduling utilises the low-power sleep state of a transceiver and aims to reduce energy wastage caused by idle listening. Idle listening occurs when the radio is on, even though there is no data to transmit or receive. Collisions are reduced by using medium reservation and carrier sensing; collisions occur when there are simultaneous transmissions from several nodes that are within the interference range of the receiver node. The medium reservation packets include a network allocation vector field which is used for virtual carrier sensing which reduces overhearing. Overhearing occurs when a node receives and decodes packets that are not destined to it. Proper scheduling can avoid energy wastage due to over-emitting; over-emitting occurs when a transmitter node transmits a packet while the receiver node is not ready to receive packets. A protocol stack is proposed that achieves an ultra-low duty cycle sleep schedule. The protocol stack is aimed at large nodal populations, densely deployed, with periodic sampling applications. It uses the IEEE 802.15.4 Physical Layer (PHY) standard in the 2.4 GHz frequency band. A novel hybrid data-link/network cross-layer solution is proposed using the following features: a global sleep schedule, geographical data gathering tree, Time Division Multiple Access (TDMA) slotted architecture, Carrier Sense Multiple Access with Collision Avoidance (CSMA/CA), Clear Channel Assessment (CCA) with a randomised contention window, adaptive listening using a conservative timeout activation mechanism, virtual carrier sensing, clock drift compensation, and error control. AFRIKAANS : 'n Draadlose sensor-netwerk is 'n verspreide netwerk stelsel wat bestaan uit miniatuur ruimtelik verspreide outonome toestelle wat ontwerp is om in harmonie saam die omgewing te meet. Elke sensor nodus besit 'n beperkte bron van energie, 'n sensor en 'n radio waardeur dit met ander sensor nodusse binne hulle kommunikasie radius kan kommunikeer. Aangesien hierdie sensor nodusse in ontoeganklike terreine kan ontplooi word, is dit nie moontlik om hulle kragbronne te vervang nie. Die radio is die hardeware komponent wat van die meeste krag gebruik in 'n sensor nodus en die optimalisering van hierdie element is noodsaaklik vir die verminder die totale energieverbruik. In die data-koppelvlak laag is daar verskeie bronne van energie vermorsing wat minimaliseer moet word: ydele luister, a uistering, oor-uitstraling, oorhoofse netwerk seine, en botsings. Slaap-skedulering maak gebruik van die lae-krag slaap toestand van 'n radio met die doel om energie vermorsing wat veroorsaak word deur ydele luister, te verminder. Ydele luister vind plaas wanneer die radio aan is selfs al is daar geen data om te stuur of ontvang nie. Botsings word verminder deur medium bespreking en draer deteksie; botsings vind plaas wanneer verskeie nodusse gelyktydig data stuur. Die medium bespreking pakkies sluit 'n netwerk aanwysing vektor veld in wat gebruik word vir virtuele draer deteksie om a uistering te verminder. Afluistering vind plaas wanneer 'n nodus 'n pakkie ontvang en dekodeer maar dit was vir 'n ander nodus bedoel. Behoorlike skedulering kan energie verkwisting as gevolg van oor-uistraling verminder; oor-uistraling gebeur wanneer 'n sender nodus 'n pakkie stuur terwyl die ontvang nog nie gereed is nie. 'n Protokol stapel is voorgestel wat 'n ultra-lae slaap-skedule dienssiklus het. Die protokol is gemik op draadlose sensor-netwerke wat dig ontplooi, groot hoeveelhede nodusse bevat, en met periodiese toetsing toepassings. Dit maak gebruik van die IEEE 802.15.4 Fisiese-Laag standaard in die 2.4 GHz frekwensie band. 'n Nuwe baster datakoppelvlak/netwerk laag oplossing is voorgestel met die volgende kenmerke: globale slaap-skedulering, geogra ese data rapportering, Tyd-Verdeling-Veelvuldige-Toegang (TVVT) gegleufde argitektuur, Draer-Deteksie-Veelvuldige-Toegang met Botsing-Vermyding (DDVT/BV), Skoon-Kanaal-Assessering (SKA) met 'n wisselvallige twis-tydperk, aanpasbare slaap-skedulering met 'n konserwatiewe aktiverings meganisme, virtuele draer-deteksie, klok-wegdrywing kompensasie, en fout beheer. Copyright / Dissertation (MEng)--University of Pretoria, 2012. / Electrical, Electronic and Computer Engineering / unrestricted

With the aim of identifying the challenges and determining the extent of the effect of these challenges on the effectiveness of the performance management systems, the performance management practices of selected public universities in Ethiopia were assessed. This assessment informed the identification of workable, customised balanced scorecard measurement variables that would ensure effective implementation of performance management systems and promote institutional success in the selected public universities in Ethiopia. An exploratory sequential mixed-methods design was adopted. First, literature was reviewed to learn about major concepts and theories on performance management systems and to establish the laws and directives that regulate performance management at public universities in Ethiopia. Qualitative interviews and quantitative questionnaires were used to collect data on the practices and the challenges experienced in implementing performance management systems in public universities in Ethiopia. The main practices and challenges identified include exclusion of employees from planning activities, management bias, supervisors’ failure to give feedback on performance appraisals, lack of experience among many of the professionals in the execution of performance management systems, and high employee turnover. The study presents and recommends a hexagonal hybrid balanced scorecard measurement model (the newly added variables being leadership and stakeholders) to make Ethiopian higher education institutions effective and efficient in measuring their overall performance. / Met die oog daarop om die uitdagings te identifiseer en die omvang van die uitwerking daarvan op die doeltreffendheid van die prestasiebestuurstelsels te bepaal, is die prestasiebestuurspraktyke van uitgesoekte openbare universiteite in Etiopië geassesseer. Hierdie assessering gee aanleiding tot die identifisering van werkbare, doelgemaakte veranderlikes van gebalanseerdetelkaart-meting, wat doeltreffende implementering van prestasiebestuurstelsels sal verseker en institusionele sukses in die uitgesoekte openbare universiteite in Etiopië sal bevorder. ʼn Verkennende sekwensiële gemengdemetodeontwerp is gebruik. Eerstens is literatuur bestudeer om meer te wete te kom oor deurslaggewende konsepte en teorieë rakende prestasiebestuurstelsels, en om te bepaal watter wette en voorskrifte prestasiebestuur by openbare universiteite in Etiopië reguleer. Kwalitatiewe onderhoude en kwantitatiewe vraelyste is gebruik om data in te samel oor die uitdagings en praktyke in die implementering van prestasiebestuurstelsels by openbare universiteite in Etiopië. Die grootste uitdagings en praktyke wat geïdentifiseer is behels uitsluiting van werknemers by beplanningsaktiwiteite, bestuursvooroordeel, toesighouers wat nie terugvoer gee oor prestasiebeoordelings nie, gebrek aan ondervinding by baie van die praktisyns in die implementering van prestasiebestuurstelsels, en hoë werknemeromset. Hierdie studie bied ʼn verteenwoordiging en aanbeveling van ʼn heksagonale hibriede gebalanseerde telkaartmetingmodel (die nuutbygevoegde elemente is leierskap en belanghebbers) vir hoëronderwysinstellings in Etiopië om hul algehele prestasie doeltreffend te meet. / Ngenhloso yokuhlonza izinselele, kanye nokuthola ububanzi nobukhulu bomthelela walezo zinselele ekusebenzeni ngendlela efanele kwezinhlelo zokuphatha nokulawula ukusebenza (performance), lolu cwaningo lwahlola futhi lwacubungula izinqubo zokuphatha nokulawula ukusebenza ezisetshenziswa ngamanyuvesi omphakathi athile, futhi akhethiweyo, ase-Ethiopia. Lokhu kuhlolwa kwezikhungo kwaholela ekutheni kuhlonzwe izindlela ezisebenzisekayo zombikokusebenza osekelwe phezu kwezinkomba ezine (balanced scorecard), okuyinto eyabe izoqinizekisa ukuqaliswa nokuqhutshwa ngendlela efanele kohlelo lokuphatha nokulawula ukusebenza futhi igqugquzele ukuthi yenziwe kahle, futhi ngempumelelo, imisebenzi yamanyuvesi omphakathi athile, akhethiweyo, ase-Ethiopia. Kulolu cwaningo kwasetshenziswa izindlela zokuhlola nokucwaninga ezixubile futhi ezilandelanayo. Okokuqala, kwabukezwa imibhalo ekhona njengamanje ephathelene nalesi sihloko ngenhloso yokufunda ngemiqondo engumongo futhi enohlonze, kanye namathiyori aphathelene nezinhlelo zokuphathwa nokulawulwa kokusebenza, futhi ukuze kutholakale ulwazi olunzulu mayelana nemithetho neziqondiso ezilawula ukuphathwa nokulawulwa kokusebenza emanyuvesi omphakathi e-Ethiopia. Izindlela zocwaningo ezasetshenziswa, yindlela yokuthola ulwazi ngokuxoxisana okujulile nababambiqhaza bocwaningo (qualitative interviews) kanye namaphephamibuzo ocwaningo (quantitative questionnaires), obekuhloswe ngakho ukuqoqa idatha mayelana nezinselele kanye nezinqubo okudlulwe kuzona ngenkathi kuqhutshwa izinhlelo zokuphathwa nokulawulwa kokusebenza emanyuvesi omphakathi e-Ethiopia. Izinselele ezinkulu kanye nezinqubo ezingumongo ezihlonziwe zibandakanya ukushiywa ngaphandle kwabasebenzi ngenkathi kwenziwa imisebenzi yokuhlela, ukuchema kwabaphathi, ukuhluleka kosuphavayiza ukuhlinzeka abasebenzi ngombiko noma umphumela obonisa ukuthi baqhube kanjani ngenkathi kuhlolwa umsebenzi wabo, ukungabi nesipiliyoni noma ulwazi olufanele kweningi labasebenzi abangogoti bemikhakha ethile (professionals) ngenkathi beqhuba izinhlelo zokuphatha nokulawula ukusebenza, kanye nezinga eliphakeme lokwesula kwabasebenzi emsebenzini. Lolu cwaningo lwethula futhi lwancoma ukuthi kusetshenziswe indlela yokukala ukusebenza ebizwa nge-hexagonal hybrid balanced scorecard measurement model (izinto ezintsha ezengeziwe eziphathelene nocwaningo wubuholi kanye nababambiqhaza) ngenhloso yokulekelela iziKhungo Zemfundo Ephakeme zase-Ethiopia ukuthi zikwazi ukukala kahle, vi futhi ngempumelelo, izinga lonkana lokusebenza kwazo. / Educational Leadership and Management / D. Ed. (Education Management)