Hybrid pixel detectors have been demonstrated to provide excellent quality detection of ionising photon radiation, particularly in X-ray imaging. Recently, there has been interest in developing a hybrid pixel detector specifically for photon dosimetry. This thesis is on the design, implementation, and preliminary characterisation of the Dosepix readout chip. Dosepix has 256 square pixels of 220 mm side-length, constituting 12.4 mm2 of photo-sensitive area per detector. The combination of multiple pixels provides many parallel processors with limited input flux, resulting in a radiation dose monitor which can continuously record data and provide a real-time report on personal dose equivalent. Energy measurements are obtained by measuring the time over threshold of each photon and a state machine in the pixel sorts the detected photon event into appropriate energy bins. Each pixel contains 16 digital thresholds with 16 registers to store the associated energy bins. Preliminary measurements of Dosepix chips bump bonded to silicon sensors show very promising results. The pixel has a frontend noise of 120 e-. In low power mode, each chip consumes 15 mW, permitting its use in a portable, battery-powered system. Direct time over threshold output from the hybrid pixel detector assembly reveal distinctive photo-peaks correctly identifying the nature of incident photons, and verification measurements indicate that the pixel binning state machines accurately categorise charge spectra. Personal dose equivalent reconstruction using this data has a flat response for a large range of photon energies and personal dose equivalent rates.

A use case for a data management system for machine-to-machine communication was defined. A centralized system for managing data flow and storage is required for machines to securely communicate with other machines. Embedded devices are typical endpoints that must be serviced by this system and the system must, therefore, be easy to use. These systems have to bill the data usage of the machines that make use of its services. Data management systems are subject to variable load and must there- fore be able to scale dynamically on demand in order to service end- points. For robustness of such an online-service it must be highly available. By following design science research as the research methodology, cloud-based computing was investigated as a target deployment for such a data management system in this research project. An implementation of a cloud-based system was synthesised, evaluated and tested, and shown to be valid for this use case. Empirical testing and a practical field test validated the proposal. / Thesis (MIng (Computer and Electronic Engineering))--North-West University, Potchefstroom Campus, 2013.

A use case for a data management system for machine-to-machine communication was defined. A centralized system for managing data flow and storage is required for machines to securely communicate with other machines. Embedded devices are typical endpoints that must be serviced by this system and the system must, therefore, be easy to use. These systems have to bill the data usage of the machines that make use of its services. Data management systems are subject to variable load and must there- fore be able to scale dynamically on demand in order to service end- points. For robustness of such an online-service it must be highly available. By following design science research as the research methodology, cloud-based computing was investigated as a target deployment for such a data management system in this research project. An implementation of a cloud-based system was synthesised, evaluated and tested, and shown to be valid for this use case. Empirical testing and a practical field test validated the proposal. / Thesis (MIng (Computer and Electronic Engineering))--North-West University, Potchefstroom Campus, 2013.

Dissertation : Fachbereich Philosophie und Sozialwissenschaften--Berlin--Freie Universität, 1976. / Bibliogr. p. 296-309.

Proefschrift Universiteit Maastricht. / Met lit. opg., reg. - Met samenvatting in het Engels. Bibliogr.: p. 459-474.

Text in Afrikaans / Uit 'n literatuurstudie en empiriese ondersoek wat onderneem is, blyk dit dat 15-40% van alle adolessente subkliniese depressie ervaar. Veranderinge en toenemende druk en eise eie aan die adolessente-fase, bring by baie adolessente depressiewe gevoelens mee. Ten spyte van hierdie omstandighede is daar egter ook baie adolessente wat hierdie fase van ontwikkeling sonder enige noemenswaardige probleme deurloop. Aaron Beck is van mening dat dit nie die omstandighede opsigself is wat tot depressie aanleiding gee nie, maar wel die betekenis wat individue aan omstandighede gee. Beck noem dat depressiewe persone tot irrasionele oortuigings, foutiewe inligting-prosessering en disfunksionele outomatiese gedagtes geneig is. Om hierdie probleem aan te spreek is ses adolessente, wat subkliniese depressie ervaar, aan Beck se kognitiewe terapie onderwerp. Die primere doel van Beck se terapie is die regstelling van bogenoemde disfunksionele kognisies. Die gevolgtrekking is dat wanneer adolessente wat subkliniese depressie ervaar, se disfunksionele kognisies reggestel word, hulle depressiewe gevoelens opgehef word. / From a literature study and empirical research which was undertaken, it seems that 15-40% of all adolescents experience subclinical depression. Changes and increasing pressure and demands, typical of the adolescent phase, causes many adolescents to experience depressing emotions. In spite of these circumstances there are also many adolescents who go through this phase in development without any significant problems. Aaron Beck is of opinion that it is not the circumstances in and of itself that lead to depression but rather the meaning that individuals attached to these circumstances. Beck mentions that depressive people are inclined to irrational beliefs, erroneous information-processing and dysfunctional automatic thoughts. To address this problem, six adolescents who experience subclinical depression, were subjected to Beck's cognitive therapy. The primary target of Beck's therapy is the correction of above mentioned dysfunctional cognitions. The conclusion is that when the dysfunctional cognitions of adolescents who experience subclinical depression can be corrected, their depressive feelings will diminish. / Educational Studies / M. Ed. (Voorligting)

Text in Afrikaans / Uit 'n literatuurstudie en empiriese ondersoek wat onderneem is, blyk dit dat 15-40% van alle adolessente subkliniese depressie ervaar. Veranderinge en toenemende druk en eise eie aan die adolessente-fase, bring by baie adolessente depressiewe gevoelens mee. Ten spyte van hierdie omstandighede is daar egter ook baie adolessente wat hierdie fase van ontwikkeling sonder enige noemenswaardige probleme deurloop. Aaron Beck is van mening dat dit nie die omstandighede opsigself is wat tot depressie aanleiding gee nie, maar wel die betekenis wat individue aan omstandighede gee. Beck noem dat depressiewe persone tot irrasionele oortuigings, foutiewe inligting-prosessering en disfunksionele outomatiese gedagtes geneig is. Om hierdie probleem aan te spreek is ses adolessente, wat subkliniese depressie ervaar, aan Beck se kognitiewe terapie onderwerp. Die primere doel van Beck se terapie is die regstelling van bogenoemde disfunksionele kognisies. Die gevolgtrekking is dat wanneer adolessente wat subkliniese depressie ervaar, se disfunksionele kognisies reggestel word, hulle depressiewe gevoelens opgehef word. / From a literature study and empirical research which was undertaken, it seems that 15-40% of all adolescents experience subclinical depression. Changes and increasing pressure and demands, typical of the adolescent phase, causes many adolescents to experience depressing emotions. In spite of these circumstances there are also many adolescents who go through this phase in development without any significant problems. Aaron Beck is of opinion that it is not the circumstances in and of itself that lead to depression but rather the meaning that individuals attached to these circumstances. Beck mentions that depressive people are inclined to irrational beliefs, erroneous information-processing and dysfunctional automatic thoughts. To address this problem, six adolescents who experience subclinical depression, were subjected to Beck's cognitive therapy. The primary target of Beck's therapy is the correction of above mentioned dysfunctional cognitions. The conclusion is that when the dysfunctional cognitions of adolescents who experience subclinical depression can be corrected, their depressive feelings will diminish. / Educational Studies / M. Ed. (Voorligting)

'n Onafhanklike, ondersoekende en verantwoordelike media word beskou as een van die belangrikste rolspelers waarvan die behoud van die demokrasie in Suid- Afrika afhanklik is. Die regte en vryhede van die media geniet grondwetlike erkenning en beskerming. As fundamentele regte en onontbeerlike komponente van mediavryheid, waarborg die Grondwet van die Republiek van Suid-Afrika, 1996 aan elkeen die reg op vryheid van uitdrukking (artikel 16) en die reg op toegang tot inligting (artikel 32). Die grondwetlike beskerming van mediavryheid bemagtig die media om (i) openbare aangeleenthede in belang van die publiek aan te spreek, (ii) die staat tot deursigtigheid, openheid en verantwoording op te roep en (iii) as teenwig teen magsmisbruik en wanpraktyke aan regeringskant op te tree. Die reg op mediavryheid is egter nie absoluut afdwingbaar nie en kan gevolglik in die toepassing daarvan beperk word. Die staat beskik oor die gesag om dié reg aan beperkings onderhewig te stel ten einde ander individuele fundamentele regte te beskerm of belangrike openbare belange te dien. Sodanige staatsoptrede is egter slegs moontlik indien dit, weens die oppergesag van die Grondwet (artikel 2), in ooreenstemming met die grondwetlike bepalings geskied. Desnieteenstaande word die media, ondanks die belangrike rol wat hulle ter behoud van die demokrasie in Suid-Afrika vervul en die grondwetlike erkenning en beskerming wat aan mediavryheid verleen word, voortdurend onder groot druk geplaas. Die meeste druk kom van die staat se kant. Die aanname en beoogde implementering van die Protection of State Information Bill, 2010 dien as mees resente voorbeeld hiervan. Staats- en administratiefregtelike beperkings op mediavryheid sal, indien die Wetsontwerp gepromulgeer word, aan die orde van die dag wees. Aangesien die voorgenome beperkings op grond van hulle potensiële ongrondwetlikheid wyd gekritiseer word, is dit die vernaamste doel van hierdie studie om die grondwetlike grense waarbinne die staat mediavryheid mag beperk, te omlyn en ondersoek in te stel na die trefwydte en grondwetlikheid van die staat se gesag om beperkings op mediavryheid te plaas. Deur die omvang van staatsgesag in die algemeen en in besonder rakende die beperking van mediavryheid, aan die hand van die relevante grondwetlike voorskrifte te ondersoek, is bevind dat alle staatsoptrede streng deur die Grondwet gereguleer word. Alhoewel die reg op mediavryheid vatbaar is vir regulering en beperking, is tot die slotsom gekom dat die Grondwet ingevolge artikels 33 en 36 duidelike grense vir die beperking daarvan deur die staat stel. Alle uitvoerende en administratiewe staatsorgane wat kragtens wetgewing en uit hoofde van die diskresionêre bevoegdhede wat aan hulle verleen word, die reg op mediavryheid beperk, moet aan die vereistes vir regverdige administratiewe optrede voldoen. Bygevolg moet alle administratiewe besluite en handelinge wat die reg op mediavryheid beperk, regmatig, redelik en prosedureel billik wees en met die verskaffing van voldoende skriftelike redes gepaard gaan. Sowel staatsregtelike as administratiefregtelike beperkings op mediavryheid moet voldoen aan die vereistes wat die algemene beperkingsklousule vir die grondwetlike beperking van fundamentele regte stel. Enige beperking van die reg op mediavryheid moet dus kragtens 'n algemeen geldende regsvoorskrif geskied en moet, met in agneming van die artikel 36-sleutelfaktore, as redelik en regverdigbaar binne 'n oop en demokratiese samelewing gebaseer op menswaardigheid, gelykheid en vryheid plaasvind. Enige staats- en administratiefregtelike beperkings op mediavryheid wat nie aan hierdie grondwetlike vereistes voldoen nie, is gevolglik ongrondwetlik. Nadat die bepalings ter beperking van mediavryheid deur die Protection of State Information Bill, 2010 krities ontleed is, is bevind dat dit nie daarin sal slaag om die grondwetlike toets te slaag nie. / LLM, North-West University, Potchefstroom Campus, 2015

Businesses' demand for information technology-(IT) capacity and IT solutions are growing daily. As available services and products expand, users require more convenience, cost savings, user-friendliness and reliability. Manufacturers of mobile devices have always been motivated to develop mobile devices which are more flexible and reliable. As a consequence of the above mentioned, the importance of business in the modern technological environment was greatly overestimated as a result of development in mobile technology. Mobile technology breaks the limitations of mobility in businesses which provides innovative possibilities Mobile distance-based services have attracted much attention because of the growing potential that it offers. Businesses need mobile options that deal with specific needs. A mobile accounting system will provide adaptability and flexibility to an entity, which at this stage has not been possible. An improved adaptability and flexibility of enterprises will have a positive impact on productivity and innovation as a result. The rapid growth and development of mobile technology creates the opportunity for the development of many innovative mobile applications. From the above it is clear that there is an existing trend that companies want to implement more mobility in their business. From an accounting perspective, small-to medium-sized businesses have simpler rules and regulations that must be obeyed (IFRS for SMEs). Thus, the point of entrance of this study will focus on the feasibility of a mobile accounting system for small to medium sized entities (SME). On a global scale, should the importance of small-to medium-sized entities (SMEs) not be overlooked. SMEs are the mainstay of most national economies and represent between 30 to 60 percent of the economy's gross domestic product. A mobile accounting system will provide managers and business owners the option to have “anytime anywhere” access to the entity's financial information. This will also allow businesses to be more mobile. Thus, invoices can be issued, receivables added, payments entered (creditors and so on) and all this can be done without physically being on the business premises. The mobile system will therefore communicate in real time with the database on the business premises which is stored electronically and so information for everyone who uses it will be updated and correct. / MCom (Accountancy), North-West University, Potchefstroom Campus, 2014

A triathlon can be described as the combination of the three athletic competencies swimming, cycling and running where each of the items is performed in a specific order and vary in distance. A triathlon is a very select sport that only attracts specific participants, seeing that constant training is necessary in order to improve fitness and skill in the three different disciplines. Being a triathlete involves a substantial amount of physical and psychological stress over several hours of continuous activity. Therefore the key aspects that drive this study are the following: * The uniqueness of triathlons and triathletes makes it important to research certain aspects such as: Who these participants are? Why they participate in triathlons? And why do they return to the event each year? * Currently most triathlon research is done in countries such as United States of America, Australia, Germany and Japan. There are also numerous studies done on triathletes, although most of these studies focus on physiological and medical aspects of these athletes. * To the best of the author’s knowledge no other study in South Africa has focused on profiling triathletes and gaining knowledge on what differentiates these participants from other endurance sport athletes. * As there is currently a deficiency of information regarding triathletes in South Africa it becomes imperative to research this market through market segmentation. With the latter in mind, the main purpose of this study was to apply market segmentation on triathletes that participate in Ironman South Africa, the only full-length Ironman held on the African continent. In order to achieve this goal a destination-based survey took place during the registration process of participants at The Boardwalk Convention Centre and Spa in Port Elizabeth. A total of 425 completed questionnaires were used in the study. An in-depth literature study was also done to review different aspects of triathlons and triathletes, including the unique nature of the sport and participants as well as analysing previous literature concerning the characteristics of triathletes. Literature also explored market segmentation and the different variables used to segment triathletes and other endurance sport athletes. From literature it became clear that motives to participate and frequency of participation could be useful in segmenting sport participants. These two variables were applied to Ironman South Africa in two separate articles. In Article 1 motives to participate was applied as a market segmentation variable. It was found that triathletes were motivated by seven motivational factors including: Challenge, Inner vie, Health and fitness, Intrinsic achievement and control, Event novelty, Group affiliation and socialisation and lastly, Respect and risk. Based on these motives three distinct clusters of triathlon participants were identified: Devotees, Enthusiasts and Aspirationals. The participants in each cluster showed statistical significant differences with regard to their motives, while age was the only variable with significant socio-demographic differences between the clusters. In Article 2, frequency of participation was used to segment Ironman South Africa participants. Significant differences were found between first time and repeat participants based on the variables: demographic, behaviour and motives to participate. Four segments were identified at Ironman South Africa based on the number of times they have previously participated in the event. The frequent flyer concept was applied which resulted in the dividing of the four participant segments into different loyalty segments. The segments were the Bronze, Silver, Gold and Platinum segment. Three marketing strategies were developed, firstly for the Bronze and Silver segments (these two segments shared similar characteristics), secondly for the Gold and Platinum segments also sharing corresponding characteristics and lastly, a marketing strategy to expand triathlons in South Africa. The information obtained from the two market segmentation variables led to an array of recommendations to attract and retain participants to Ironman South Africa events. Also recommendations focus on how to expand triathlon events in South Africa. Significant contributions were made to literature regarding the profile of the Ironman South Africa participants and how these triathletes compare to other endurance sport athlete. / MCom (Tourism Management), North-West University, Potchefstroom Campus, 2014