Ultrafine particle emissions in motor-vehicle exhaust are associated with cardiopulmonary health impacts and increased mortality. The emission, evolution, and exposure-uptake of these particles, one hundred nanometers and smaller in diameter, are fundamentally quantified by the number concentration as a function of particle size. Ultrafine particle number distributions are widely varying and fast changing as they are strongly influenced by local environmental conditions and variation in vehicle operation and maintenance. Research and regulation to quantify and control such emissions rely on measurement of the number distribution of ultrafine particles in vehicle exhaust and by the roadside. Instruments to make such measurements are commercially available, but they are expensive, non-portable, and have slow response times. A new instrument, the NanoAPA, is being developed for these in-situ applications as an inexpensive, portable, and real-time instrument. The instrument is designed to perform ultrafine particle sizing and counting through electronic control of a microfabricated device that charges sampled airborne particles with a corona ionizer and then incrementally size-separates, collects, and counts the number of particles in the aerosol. The focus of this thesis was the development and characterization of the smallest device known that can perform these sizing and counting functions. The device miniaturizes a classical instrument from the aerosol field, the double-condenser of Whipple (1960) used for the sizing and counting of atmospheric ions, into a microfabricated device designed to utilize voltage-and-flowrate-variable electrophoresis to measure ultrafine particle aerosols. Performance characterization of the microfabricated device required development of an apparatus for the generation and conditioning of aerosols appropriate to this application. This Standard Aerosol apparatus was demonstrated to produce repeatable, temperature and humidity stable, charge-neutral, monodisperse exhaust-analog aerosols of particles 10 to 100 nanometer in diameter. The microfabricated device was characterized with the Standard Aerosol apparatus for the operating conditions of 0.1 to 1.5 liter per minute flow rate and 0 to 3000 volt separator voltage. Results of the characterization demonstrated effective selection and collection of solvent droplets in the diameter range 10-100nm. The selection and collection results for engine-exhaust analog particles were inconclusive, likely due to particle re-entrainment. Repeatable measurements of particle number proved elusive, likely due to electrical field interference, the limited particle concentration obtainable from the Standard Aerosol apparatus, and signal-to-noise and temporal stability issues with the electrometer electronics. Recommendations are made for approaches likely to overcome these issues.

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Published Article / To start with, "Corporate Social Responsibility" (CSR) appears a misnomer as it suggests a 'big business only' connotation. Rather, "Business Social Responsibility" (BSR) appears a better alternative because it accommodates all sizes of business. Despite progress in the business / society relationship, SMMEs on the African continent continue being neglected as far as BSR research is concerned. Unlike in the West, there are no frameworks, tools, and instruments to guide those interested in the SMME / BSR nexus in the African context. As it turns out, scholars, researchers, policy makers, and owner / managers interested in the SMME / BSR nexus in Africa have no choice but to rely on frameworks, tools, and metrics designed for European and American contexts. This is in spite of Visser's (2007) caution that the Euro-American frameworks are inappropriate for the African situation. This paper makes a case for the development of an African context specific SMME / BSR framework(s) and measurement instrument(s).

This work presents development system LabVIEW and the possibility to create virtual measuring devices. Particular realization of virtual measuring device within the frame of this work is applied on measurement of basic characteristics of claw-pole alternator. The structure and the principle of function of this alternator is described in brief. Created virtual measurement device is described in detail. The entire block scheme, that is the source code for LaBVIEW development system, is attached only in electronic form. The printed version contains front panel of the device and almost all the structures of block scheme.

In current turbulent times, sustainable relationships hinge on the mutual understanding created by a clear communication strategy between a business unit and its stakeholders. The purpose of this research was to develop a corporate communication strategy model for the University of Pretoria Centre for Sustainable Malaria Control (UP CSMC). Purposive sample testing was conducted to determine the stakeholder perceptions of the main variables of this study, being: communication management, social media, stakeholder relationships and the corporate communication strategy. Objectives were achieved, the hypotheses stated duly tested and the results applied towards the development of a conceptual framework for a more formal and sustainable corporate communication strategy with a specific focus on communication about science related matters. This study contributes to effective stakeholder communication between the organisation and its stakeholders through the introduction of communication mediums like social media and traditional media. This research proposes a corporate communication strategy with integrated social media platforms, which helps organisations manage the relationships with their stakeholders. It suggests that when communicating about science, the UP CSMC should aim to communicate through different forms of interpersonal communication such as one-on-one engagements, events, seminars, exhibitions and other presentations. The Centre's corporate communication strategy should also include objectives to improve communication about science through interpersonal communication with stakeholders. The new model proposes concepts that focus on an analysis of the environment, identification of strategic issues, development of communication hierarchy, communicating an effective communication strategy, developing a strategic communication plan and monitoring complete embedment. The new proposed model is founded on an empirical study that comprises a descriptive study based on 45 developed questionnaires developed specifically for this study and answered by stakeholders of the UP CSMC. The standard corporate communication model presented by Steyn and Puth (2000) was analysed, evaluated and tailored to fit the organisation's requirements. The proposed model developed in this study includes critical components relevant to the establishment and maintenance of sustainable relationships and can be adopted by any organisation with similar communication challenges as covered in this study. / Dissertation (MCom)--University of Pretoria, 2016. / Communication Management / MCom / Unrestricted

As battery manufacturing is enclosed with multiple quality and safety requirements, the batteryindustry needs adequate Measurement Systems (MS) to provide high product quality and ensure a safe working environment. The study purpose was to improve the performance of an MS for battery production by utilizing MSA and Six Sigma methodology, and to make appropriate recommendations for improvement and future control. The study included 28 measurement instruments which were evaluated by the utilization of a framework consisting of five different errors identified in the literature, namely bias, linearity, stability, reproducibility and repeatability. This framework is considered as the theoretical contribution of this study. The improvement methodology DMAIC (Define-Measure-Analyze-Improve-Control) was used to perform the case study. The results indicate an overall improved MS and generated improvement suggestions of three recurrent scenarios that arose in the analysis. Moreover, a company adopted control plan with an intention to serve as a basis for future work within MSA is presented and concerns the practical contribution of this work. The results provide helpful support as well as establish a foundation of how to maintain a well-performing MS for Northvolt. By implementing the suggested recommendations, the potential saving was estimated to 395 000 SEK annually. / En mätsystemanalys genomfördes hos batteritillverkaren Northvolt. Då batteriproduktionomgärdas av flera kvalitets- och säkerhetskrav behöver batteriindustrin tillförlitliga mätsystem för att generera hög produktkvalitet samt upprätthålla en säkerhet för användare. Studien syftade till att förbättra prestandan hos ett mätsystem inom batteriproduktion genom användandet av mätsystemanalys och Sex Sigma-metodik, samt att ge lämpliga rekommendationer för förbättringar och framtida kontroll. Studien inkluderade 28 mätinstrument som utvärderades genom användningen av ett ramverk bestående av fem olika mätsystemfel identifierade i litteraturen, nämligen bias, linearity, stability, reproducibility och repeatability. Detta ramverk betraktas som det teoretiska bidraget från denna studie. Förbättringmetodiken DMAIC (Define-Measure-Analyze-Improve-Control) användes för att utföra fallstudien. Resultaten visar på ett övergripande förbättrat mätsystem och genererade förbättringsförslag på tre återkommande scenarier som uppstod i analysen. Dessutom presenteras en företagsanpassad kontrollplan med avsikt att utgöra en grund för framtida arbete inom mätsystemanalys och ses det praktiska bidraget från denna studie. Resultaten förblir ett användbartstöd samt skapar en grund för hur Northvolt upprätthåller ett högpresterande mätsystem. Genom att säkerställa prestandan av mätsystemet uppskattades den potentiella besparingen till 395 000 SEK årligen.

Philosophiae Doctor - PhD / Pain is a complex biopsychosocial phenomenon that can have a profound impact on people's lives (Access Economics [AE], 2007). lts clinical relevance is well known - pain is suggestive of "actual or potential tissue damage" and plays a role in the diagnosis and clinical management of diseases and/or injury (International Association for the Study of Pain [IASP], 1986). It has both sensory and emotional aspects and is behaviourally expressed by how it is communicated by the sufferer and by its effect on the sufferer's behaviour (IASP, 1986; Linton, 2005; AE, 2007). Even though the experience of pain is associated with tissue damage or is described in terms of such damage, this association is variable so that "the size of an injury can be a poor guide as to how much an individual experiences pain" (AE, 2007). In fact, pain can exist without an objective evidence of tissue damage making pain the "ultimate subjective experience" (Odendaal, 2006). This phenomenon may relate to the fact that the interpretation of nociceptive signals as pain is influenced by a number of personal and environmental factors including past experience, integrity of the nervous system, beliefs and the situation in which tissue damage occurs (Eccleston, 2001; Turk, 2002a; Flor and Hermann, 2004; AE, 2007). As such, decisive and objective measurements are difficult to arrive at and pain is not always easily assessed by the healthcare provider. The translation of pain from acute to chronic however, means that pain and discomfort remains beyond the normal time of healing and by definition, persists either continuously or intermittently for 3 months or longer (Elliot et al., 1999). This changes the physiognomy of pain and the condition of chronic pain ensues. Chronic pain is an important but often neglected public health problem. It is disabling and associated with interference in normal activities of daily living (ADLs) such as work, home chores, family and sporting activities. Research shows that chronic pain is a key complaint that motivates many to seek health care (Crook et al., 1984, 1989; Sullivan et al., 1990; Smith et al., 1996; Mantyselka et al., 2001, 2002; Eriksen et al., 2004; AE, 2007) leading to high and ongoing consumption of treatments (AE, 2007). In fact, studies have shown that persons with chronic pain use health services up to five times more frequently than the rest of the population (Von Korff et al., 1990, 1991; Elliot et al., 1999; Eriksen et al., 2004). Side-effects of treatment are common with medication use including gastric problems such as ulcerations, nausea, constipation and mental slowing or confusion which can affect functioning. Chronic pam is also associated with mood and sleep disturbances such as depression or adjustment problems and trouble getting to sleep and/or frequent wakening during the night. For the sufferer, the effect of disuse of the aspect of the body in which pain is experienced is another manifestation of chronic pain. Muscles and joints become de-conditioned and pain sufferers may lose general body fitness (AE, 2007). Within the community, pain is a common cause of considerable suffering and disability affecting the general health and quality of life of individuals (Von Korff et al., 1990, 1992; Magni et al., 1990,1993; Walsh et al., 1992; Smith et al., 1996,2001; Verhaak et al., 1998; Elliot et al., 1999, 2002; Blyth et al., 2001; Reyes-Gibby et al., 2002; Lanteri-Minet et al., 2003). Significant amounts of working days are lost among the labour force impacting a profound economic and social toll on society (Bowsher et al., 1991; Elliot et al., 1999; Blyth et al., 2003; Igumbor et al.,2003). Simply put, "chronic pain is a human tragedy" (Odendaal, 2006). It is a serious and common problem that causes distress to patients and their caregivers, is a burden on health care professionals and health care resources and results in significant lost productivity. Chronic pain is therefore a problem of public health importance.

The purpose of this study was to develop an economic career choice instrument for grade 121earners, which conforms with the requirements of cultural fairness, validity and reliability. The various facets of adolescent development were analysed from the literature. Self-knowledge (identity) and career knowledge were analysed from various theoretical perspectives. The various facets of adolescent development had a direct influence on the career choice of learners. These facets served as a basis for the development of the different sections for the career choice instrument. In the empirical study a survey was conducted involving 321 grade 12 learners randomly selected from secondary schools in the Potchefstroom region. These learners completed the newly developed instrument. The reliability of the career choice instrument was determined by using the Cronbach Alpha Coefficient. Factor analysis were used to determine the validity of each section of the instrument. In order to determine whether the career choice instrument was culturally fair, a series of one-way ANOVAS, followed by Tukey tests were performed, whereafter effect sizes were determined. In the study good reliability indices were obtained for all sections of the measuring instrument. The reliability indices obtained from the Cronbach Alpha Coefficients, coincided relatively well with the reliability indices obtained for the MB-10 (Meyer Interest Questionnaire), the Jung Personality questionnaire and the LISRES-Y. Concerning the cultural aspect, the different race groups, white, black and coloured learners, differed significantly in respect of social development and values. Recommendations for further research for the use of the instrument in teaching practice are formulated from the research results, in particular with reference to the designing of a career choice instrument. / Thesis (Ph.D. (Education))--Potchefstroom University for Christian Higher Education, 2001

The purpose of this study was to develop an economic career choice instrument for grade 121earners, which conforms with the requirements of cultural fairness, validity and reliability. The various facets of adolescent development were analysed from the literature. Self-knowledge (identity) and career knowledge were analysed from various theoretical perspectives. The various facets of adolescent development had a direct influence on the career choice of learners. These facets served as a basis for the development of the different sections for the career choice instrument. In the empirical study a survey was conducted involving 321 grade 12 learners randomly selected from secondary schools in the Potchefstroom region. These learners completed the newly developed instrument. The reliability of the career choice instrument was determined by using the Cronbach Alpha Coefficient. Factor analysis were used to determine the validity of each section of the instrument. In order to determine whether the career choice instrument was culturally fair, a series of one-way ANOVAS, followed by Tukey tests were performed, whereafter effect sizes were determined. In the study good reliability indices were obtained for all sections of the measuring instrument. The reliability indices obtained from the Cronbach Alpha Coefficients, coincided relatively well with the reliability indices obtained for the MB-10 (Meyer Interest Questionnaire), the Jung Personality questionnaire and the LISRES-Y. Concerning the cultural aspect, the different race groups, white, black and coloured learners, differed significantly in respect of social development and values. Recommendations for further research for the use of the instrument in teaching practice are formulated from the research results, in particular with reference to the designing of a career choice instrument. / Thesis (Ph.D. (Education))--Potchefstroom University for Christian Higher Education, 2001