No description available.

In a Doubly-fed Induction Generator (DFIG) wind energy conversion system, the rotor of a wound rotor induction generator is connected to the grid via a partial scale ac/ac power electronic converter which controls the rotor frequency and speed. In this research, detailed models of the DFIG wind energy conversion system with Sinusoidal Pulse-Width Modulation (SPWM) scheme and Optimal Pulse-Width Modulation (OPWM) scheme for the power electronic converter are developed in detail in PSCAD/EMTDC. As the computer simulation using the detailed models tends to be computationally extensive, time consuming and even sometimes not practical in terms of speed, two modified approaches (switching-function modeling and average-value modeling) are proposed to reduce the simulation execution time. The results demonstrate that the two proposed approaches reduce the simulation execution time while the simulation results remain close to those obtained using the detailed model simulation.

No description available.

The transmission and internalization of values are the primary processes that occur during socialization. A recent approach integrates existing theories and research findings into a comprehensive model of socialization. According to the domains of socialization approach, there is no general principle governing socialization but rather it occurs in different domains of caregiver-child interactions. Grusec and Davidov (2010) outlined five socialization domains, which involve controlling children’s behaviour by external means (control domain), protecting children from harm and relieving their distress (protection domain), teaching children information or skills outside of the discipline or distress setting (guided-learning domain), managing children’s environment to increase desirable role models (group participation domain), and accommodating each other’s wishes (mutual reciprocity domain). Previous work demonstrated the utility of the domains of socialization approach for the study and understanding of value acquisition (Vinik, Johnston, Grusec, & Farrell, 2013). The present study expanded on this work by focusing on processes within the family. A modified narrative methodology was used to explore aspects of the value acquisition process. Autobiographical narratives of 294 emerging adults about a time they learned an important value from a caregiver were analyzed. The sample included participants from four ethnic backgrounds. Findings provided further support for the usefulness of the domains of socialization approach to the study of value development, as events recalled in narratives were categorized into all domains but reciprocity. Values learned in the control domain were most frequently reported but were associated with the lowest levels of internalization. The highest level of value internalization was found to occur in the group participation domain, drawing attention to the importance of observing the behaviour of others. Socialization domains were associated with particular types of lesson content. The guided learning and group participation domains were associated with more positive and less negative emotional valence compared to the other domains. In turn, absence of negative valence was significantly related to better confidence in accuracy of memory reported in narratives, indicative of quality of information processing and learning. Most effects were not moderated by demographic variables providing support to the universal applicability of the domains of socialization approach.

Das Konzept Value at Risk (VaR) scheint sich als Standard im Rahmen von internen Risikomanagementmodellen in der Praxis durchzusetzen. Als quantitatives Risikomaß setzt es sich aus einem Volatilitätsmaß, der Modellierung von Verteilungen von Wertpapierrenditen und einem Bewertungsmodell zusammen. Die vorliegende Arbeit untersucht nun empirisch welche Bedeutung diese Komponenten für den VaR eines einfachen Aktienportefeuilles haben. Dabei zeigt sich, daß die Wahl des Volatilitätsmaßes keinen signifikanten Einfluß auf die Ermittlung des VaR für ein Aktienportefeuille hat. Sowohl die Annahme über die Verteilung der Aktienrenditen als auch der Bewertungsansatz mit dem das Aktienportefeuille abgebildet wird, können gravierende Änderungen im VaR nach sich ziehen. Diese Ergebnis läßt daher den Schluß zu, daß bei der Ermittlung der Eigenkapitalvorsorge im Rahmen der Kapitaladäquanzrichtlinie die Wahl des geeigneten Bewertungsmodells als auch der Verteilungsfunktion von großer Bedeutung sind. (Autorenreferat) / Series: Working Papers SFB "Adaptive Information Systems and Modelling in Economics and Management Science"

Value based management is a process that can be used to determine a business’s value drivers. It attempts to determine how the drivers link to value creation, and then break down the value drivers into achievable activities that can be pursued by employees. Due to strict medicine pricing regulations in the country, it is becoming increasingly difficult for pharmacy businesses to stay profitable. This study set out to develop a value based management framework that could be used by pharmacy management in order to maximise value creation in the business and help ensure its survival despite the strict pricing regulations. Secondary objectives were to contextualise the term “value based management”, to identify the value drivers in a pharmacy business and to determine the extent to which value based management and its principles are being applied in pharmacies in the North West region of South Africa. The research study began in the literature where the term “value based management” was introduced and a literature study was done to conceptualise the term by investigating why value based management and value creation were important. Value based management metrics, the components of value based management; and key success factors for the implementation of value based management principles were investigated. A further literature study was done to identify possible value drivers in a pharmacy business. An empirical study was conducted among registered pharmacists in the North West region of South Africa. Using the value drivers identified in the literature study as constructs, a questionnaire was designed to explore participants’ level of exposure to (and knowledge of) value based management as well as the extent to which the principles of value based management were being applied at the pharmacy businesses where participants were employed. Analysis of the responses showed the questionnaire to be reliable and valid. The results of the study highlighted that many respondents’ lack knowledge regarding the constructs (value drivers), cost price in the dispensary and cost of wages. Constructs (value drivers) that were better understood included product mix in the front shop and debtors’ control. Constructs (value drivers) that were best managed at the pharmacies where participants were employed, were cost price in the front shop and stock control. Constructs (value drivers) that were not as thoroughly managed were sales growth in the front shop and cost of wages. Conclusions regarding the findings of the research study were presented and recommendations were made. The research study was evaluated opposite the primary and secondary objectives with the conclusion that both were achieved. Finally, recommendations for further research into value based management and the application of its principles in pharmacy businesses were proposed. / Thesis (MBA)--North-West University, Potchefstroom Campus, 2013.

Value based management is a process that can be used to determine a business’s value drivers. It attempts to determine how the drivers link to value creation, and then break down the value drivers into achievable activities that can be pursued by employees. Due to strict medicine pricing regulations in the country, it is becoming increasingly difficult for pharmacy businesses to stay profitable. This study set out to develop a value based management framework that could be used by pharmacy management in order to maximise value creation in the business and help ensure its survival despite the strict pricing regulations. Secondary objectives were to contextualise the term “value based management”, to identify the value drivers in a pharmacy business and to determine the extent to which value based management and its principles are being applied in pharmacies in the North West region of South Africa. The research study began in the literature where the term “value based management” was introduced and a literature study was done to conceptualise the term by investigating why value based management and value creation were important. Value based management metrics, the components of value based management; and key success factors for the implementation of value based management principles were investigated. A further literature study was done to identify possible value drivers in a pharmacy business. An empirical study was conducted among registered pharmacists in the North West region of South Africa. Using the value drivers identified in the literature study as constructs, a questionnaire was designed to explore participants’ level of exposure to (and knowledge of) value based management as well as the extent to which the principles of value based management were being applied at the pharmacy businesses where participants were employed. Analysis of the responses showed the questionnaire to be reliable and valid. The results of the study highlighted that many respondents’ lack knowledge regarding the constructs (value drivers), cost price in the dispensary and cost of wages. Constructs (value drivers) that were better understood included product mix in the front shop and debtors’ control. Constructs (value drivers) that were best managed at the pharmacies where participants were employed, were cost price in the front shop and stock control. Constructs (value drivers) that were not as thoroughly managed were sales growth in the front shop and cost of wages. Conclusions regarding the findings of the research study were presented and recommendations were made. The research study was evaluated opposite the primary and secondary objectives with the conclusion that both were achieved. Finally, recommendations for further research into value based management and the application of its principles in pharmacy businesses were proposed. / Thesis (MBA)--North-West University, Potchefstroom Campus, 2013.

The recession of 2008/09 was the worst decline of global markets since the Great Depression in the 1930's. Some international markets lost 30 - 50% of its value in the period July to October 2008. The main reason for this dramatic drop in investor demand was the sub prime crisis in the USA where growth was fuelled by providing loans to house owners who could not afford the mortgage payments. Platinum, which is the biggest mining sector in South Africa both in terms of revenue and employment, was not spared this sudden decrease in demand. Platinum market price lost more than 50% of its value, free-falling from a level of over $2000/oz to below $1 000/oz in three months. A recession poses a massive challenge to the management teams of companies. Their main task of ensuring shareholder value growth comes under enormous pressure from macro-economic factors outside of their control. Strategic objectives based on high growth and demand scenarios have to be adapted to a low demand and negative growth environment. This study embarks on a journey to determine what strategies the different management teams of the five top South African platinum mining companies implemented and how successful they were in optimising shareholder value during the recession period. The impact of risk and return on investor demand were discussed on a theoretical level and tested on a practical level by evaluating the performances of individual companies and finding correlations between company performance and shareholder value optimisation. Companies who performed well by maintaining good profit margins, maintaining dividend payouts, managing risks well and continuing to build a good platform for future profit growth performed the best in optimising shareholder value during the recession period. Recommendations are made based on theoretical and practical best practices for how to optimise shareholder value during future recessionary times. Opportunities for companies in the platinum mining industry for the next 3 - 5 years are also evaluated and summarized. / Thesis (MBA)--North-West University, Potchefstroom Campus, 2011

The recession of 2008/09 was the worst decline of global markets since the Great Depression in the 1930's. Some international markets lost 30 - 50% of its value in the period July to October 2008. The main reason for this dramatic drop in investor demand was the sub prime crisis in the USA where growth was fuelled by providing loans to house owners who could not afford the mortgage payments. Platinum, which is the biggest mining sector in South Africa both in terms of revenue and employment, was not spared this sudden decrease in demand. Platinum market price lost more than 50% of its value, free-falling from a level of over $2000/oz to below $1 000/oz in three months. A recession poses a massive challenge to the management teams of companies. Their main task of ensuring shareholder value growth comes under enormous pressure from macro-economic factors outside of their control. Strategic objectives based on high growth and demand scenarios have to be adapted to a low demand and negative growth environment. This study embarks on a journey to determine what strategies the different management teams of the five top South African platinum mining companies implemented and how successful they were in optimising shareholder value during the recession period. The impact of risk and return on investor demand were discussed on a theoretical level and tested on a practical level by evaluating the performances of individual companies and finding correlations between company performance and shareholder value optimisation. Companies who performed well by maintaining good profit margins, maintaining dividend payouts, managing risks well and continuing to build a good platform for future profit growth performed the best in optimising shareholder value during the recession period. Recommendations are made based on theoretical and practical best practices for how to optimise shareholder value during future recessionary times. Opportunities for companies in the platinum mining industry for the next 3 - 5 years are also evaluated and summarized. / Thesis (MBA)--North-West University, Potchefstroom Campus, 2011

In policy contexts valuations may be required not only for the most inclusive good considered but also the relevant sub-areas or components which are nested within the broader good. Valuation of differing levels of quantity/quality, referred to here as scope, provides many challenges to the researcher. Through considering the sensitivity of welfare measures to scope and the valuation sequence used, this thesis was undertaken to investigate the difficulties in and prospects for using CV to estimate the non-market value of nested goods. Using a mixed methodology survey design, the case study focuses on the use of the contingent valuation method to estimate non-market benefits from a saline flood alleviation scheme in Broadland, located in Eastern England. A scheme to protect the `whole' area from saline flooding was compared to five separate `part' schemes which would only protect nested sub-areas of Broadland. Insensitivity to scope was observed within both a split sample comparison of `whole' and `part' valuations and a same sample comparison where the `part' scheme was valued first. The prior valuation of the `whole' scheme did induce sensitivity to scope between `whole' and `part' schemes, but this effect can be interpreted in terms of either economic theory, consistency pressures or the use of a more natural valuation sequence. However, the prior valuation of the `whole' scheme also induced split sample sensitivity to good characteristics between the `part' schemes. Overall the explanation for the results given cannot be monopolised by either contingent valuation supporters or their critics. In the case of Broadland flood alleviation, the validity of the valuations presented remains unclear but some interesting findings suggest future directions for research.