The forecasting of Eskom transmission electrical network demands is a complex task. The lack of historical data on some of the network components complicates this task even further. In this dissertation a model is suggested which will address all the requirements of the transmission system expansion engineers in terms of future loads and market trends. Suggestions are made with respect to ways of overcoming the lack of historical data, especially on the point loads, which is a key factor in modelling the electrical networks. A brief overview of the transmission electrical network layout is included to provide a better understanding of what is required from such a forecast. Lastly, some theory on multiple regression, neural networks and qualitative forecasting techniques is included, which will be of value for further model developments. / Computing / M. Sc. (Operations Research)

The research problem that this study sought to address stemmed from a lack of knowledge about South African organizations and a dearth of empirical, quantitative research into organizations, organization structure and organization climate in this country. Five research hypotheses were formulated to address this problem and its attendant subpriJblems. A comprehensive review of the related literature and research was c~trried out and Organization Theory was traced to its earliest beginnings. A number of schools hased on Max Weber's bureaucratic ideal type were described and contrasted. Much attention was paid to the work of the Aston group m the United Kingdom and to their efforts to operationalize Weberian concepts and to incorporate them into a replicable body of quantitative research. Points of departure were re-examined and some new twists to Systems Theory and Structural Functionalism were considered. It was established that the demographic characteristics of both the sample and the population were similar enough for the results of this study to be generalised to the population with some degree of confidence. Much care was taken to test and validate each of the scales that comprised the questionnaire, and item analyses and factor analyses were carried out for every variable and group of variables. The measures developed in other parts of the world and by other researchers performed very well in a South African setting - as did the measures developed specifically for this study. Statistical associations and causal relationships between the various sets of variables, both at the sector level and at individual industry subgroup level, were sought by means of multiple regression analyses. Broad support was found for a 'culture-free hypothesis' that there are a number of stable relationships between organizations and their context; and these relationships will be constant in direction and strength regardless of differences in structures, or in contexts of structures between societies. Importantly, there were also a number of significant differences between this study and the findings of other studies which reflected South Africa's unique blend of developed and developing cultures and value systems. These differences provide fertile ground for future research in the field of Organization Theory. / Business Management / DBL

The relationship between the role of leadership and agricultural cooperatives performance were examined in East, West and South Ethiopia. The hypotheses were tested in a survey of N=162 leaders, managers and directors of primary coffee farmers cooperatives. The results of the test confirmed the overall positive relationship between the role of leadership and agricultural cooperatives performances. This study highlights and gives general view into how the role of leadership can significantly contribute to cooperatives business performances. The results and findings of the analysis indicated that leaders who are most effective at business performances are those who utilize leadership behavior and the skills and trainings required in the cooperatives business organizations. The study encourages further and comprehensive research into the interconnection between the role of leadership, education and skills of leaders, financial management knowledge and decision making competency. The study followed cross-sectional survey design, and employed evaluative quantitative analysis method. The analysis was based on primary data generated through a structured questionnaire distributed to the respondents. Responses to research statements were scaled and converted to analyze the quantitative data of dependent and independent variables based on the role of leadership and associated performance variables. The findings from correlation and multiple regressions in testing the hypotheses showed that there are significant and positive relationship between each of the five independent variables and a dependent variable of business performances. The study concluded that leadership role was very important in cooperatives business performance and, therefore, recommended that leaders of coffee farmers’ cooperatives organizations that wanted to improve the efficiency and effectiveness of their businesses performances need to implement the suggestions stated in the recommendation part of this study about the leadership roles. / Business Management / DBL

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The relationship between the role of leadership and agricultural cooperatives performance were examined in East, West and South Ethiopia. The hypotheses were tested in a survey of N=162 leaders, managers and directors of primary coffee farmers cooperatives. The results of the test confirmed the overall positive relationship between the role of leadership and agricultural cooperatives performances. This study highlights and gives general view into how the role of leadership can significantly contribute to cooperatives business performances. The results and findings of the analysis indicated that leaders who are most effective at business performances are those who utilize leadership behavior and the skills and trainings required in the cooperatives business organizations. The study encourages further and comprehensive research into the interconnection between the role of leadership, education and skills of leaders, financial management knowledge and decision making competency. The study followed cross-sectional survey design, and employed evaluative quantitative analysis method. The analysis was based on primary data generated through a structured questionnaire distributed to the respondents. Responses to research statements were scaled and converted to analyze the quantitative data of dependent and independent variables based on the role of leadership and associated performance variables. The findings from correlation and multiple regressions in testing the hypotheses showed that there are significant and positive relationship between each of the five independent variables and a dependent variable of business performances. The study concluded that leadership role was very important in cooperatives business performance and, therefore, recommended that leaders of coffee farmers’ cooperatives organizations that wanted to improve the efficiency and effectiveness of their businesses performances need to implement the suggestions stated in the recommendation part of this study about the leadership roles. / Business Management / DBL

在可預見之未來無線點對點的世界裡，資訊交易就如同現實世界人與人間的交易模式，需考量到交易資訊的成本、價值與人際關係衡量之因素；傳統廣告行銷的效率問題也待創新的資訊交易平台來解決。本研究提出的資訊交易模型，以人性考量為基礎，在各種不同情境下，動態衡量資訊成本、價值與使用者間關係，透過助理軟體，協助加入資訊交易平台之個體，以更便利方式進行資訊交易，預期讓交易結果更貼近使用者的需求；而企業方面也能透過點與點之間快速傳遞資訊的特性，預期以更低成本、更高效率，完成商務行銷目的，達到破壞性行銷之目標。 / This paper presents a novel ambient e-service aiming at distributed marketing through sensible bartering in foreseeable wireless Peer-to-Peer (WP2P) environments. A variety of influential factors (e.g., cost, value, relationship) are proposed and formalized for empowering the bartering mechanism, unfolding a rich arena of ambient distributed trading and a disruptive paradigm of e-marketing.

網際網路的發展讓人們的生活起了變化，Web2.0的概念更是增加了人們對網際網路的依賴性，我們成為網路內容的生產者、我們在社交網站上發表、追縱朋友的動態，以及取得全球世界各地的資訊。在這無限的虛擬空間中隱含的巨大商機，讓各大企業紛紛而至，因而加速了Web2.0社群網站的發展，維持與增加網站流量更是成為社群網站生存的關鍵與重要的績效指標。但社群網站該如何從流量指標之變化來評斷社群網站之績效呢?這是令我們最好奇之處。 藉由Google Analytics提供的流量分析工具，本研究蒐集了台灣四間社群網站1-3年間的流量資訊進行分析，考量蒐集之資訊具時間序列性質特性，本研究首先採用移動視窗法重新進行資料的整理，並據此概念應用在後續的統計分析。此外，本就以指數加權平均法及多元迴歸分析進行流量異常值之偵測，最後，對照各網站重大事件里程碑並與各網站業主進行一對一深訪。故本研究實際上包含質、量化之分析結果。 本篇研究四間個案網站為例，並依網站創造的服務與使用者互動情形流量將其區分為社交互動型與資訊交換型網站，並歸納其在網站流量指標上不同特徵表現及各自可參考之績效評估指標。同時，本研究採用多元迴歸分析做為社群網站績效評估模型，並企圖建構一績效評估分析流程期以做為後續研究者針對網站流量相關研究之參考。 / The development of Internet makes a great influence on human society and the development of Web2.0 enhances human’s dependence on the internet and becomes a channel of social connections. Currently, most contents of the Internet are generated by common users who could retrieve information through the entire network and trace their friends’ actions over the Social Network Sites (SNSs).Owing to the potential business opportunities on the internet, companies try to enter the market causing the prosperities of SNSs. Maintaining or even increasing traffic flows become a critical issue for SNSs to survive in the competitive market. However, how to evaluate the performance of SNSs based on traffic flow indices remains unsolved.This study collected Google Analytics data for 1-3 years from four SNSs’, respectively.Consider the time series charactics, this study applied “Moving Windows“ to organize the data for further statistical analysis.In addition, Exponentially Weighted Moving Average and Multiple Regression Analysis were used to detect the abnormal traffic flows. Finally, these abnormal records were compared with the important events and one-on-one interviewings with the SNSs operators were conducted. The results of this study are based on qualitative and quentitative analysis. This research studiesd four SNSs that were categorized into information-oriented and interaction-oriented services based on their services and users’ interaction. The SNSs at different categories behaved differently following certain characteristics defined previously.A performance evaluation process was developed as a reference for further studies.

This thesis is divided into three main parts. In the first, we discuss that, although permutation tests can provide exact control of false positives under the reasonable assumption of exchangeability, there are common examples in which global exchangeability does not hold, such as in experiments with repeated measurements or tests in which subjects are related to each other. To allow permutation inference in such cases, we propose an extension of the well known concept of exchangeability blocks, allowing these to be nested in a hierarchical, multi-level definition. This definition allows permutations that retain the original joint distribution unaltered, thus preserving exchangeability. The null hypothesis is tested using only a subset of all otherwise possible permutations. We do not need to explicitly model the degree of dependence between observations; rather the use of such permutation scheme leaves any dependence intact. The strategy is compatible with heteroscedasticity and can be used with permutations, sign flippings, or both combined. In the second part, we exploit properties of test statistics to obtain accelerations irrespective of generic software or hardware improvements. We compare six different approaches using synthetic and real data, assessing the methods in terms of their error rates, power, agreement with a reference result, and the risk of taking a different decision regarding the rejection of the null hypotheses (known as the resampling risk). In the third part, we investigate and compare the different methods for assessment of cortical volume and area from magnetic resonance images using surface-based methods. Using data from young adults born with very low birth weight and coetaneous controls, we show that instead of volume, the permutation-based non-parametric combination (NPC) of thickness and area is a more sensitive option for studying joint effects on these two quantities, giving equal weight to variation in both, and allowing a better characterisation of biological processes that can affect brain morphology.

The forecasting of Eskom transmission electrical network demands is a complex task. The lack of historical data on some of the network components complicates this task even further. In this dissertation a model is suggested which will address all the requirements of the transmission system expansion engineers in terms of future loads and market trends. Suggestions are made with respect to ways of overcoming the lack of historical data, especially on the point loads, which is a key factor in modelling the electrical networks. A brief overview of the transmission electrical network layout is included to provide a better understanding of what is required from such a forecast. Lastly, some theory on multiple regression, neural networks and qualitative forecasting techniques is included, which will be of value for further model developments. / Computing / M. Sc. (Operations Research)

The research problem that this study sought to address stemmed from a lack of knowledge about South African organizations and a dearth of empirical, quantitative research into organizations, organization structure and organization climate in this country. Five research hypotheses were formulated to address this problem and its attendant subpriJblems. A comprehensive review of the related literature and research was c~trried out and Organization Theory was traced to its earliest beginnings. A number of schools hased on Max Weber's bureaucratic ideal type were described and contrasted. Much attention was paid to the work of the Aston group m the United Kingdom and to their efforts to operationalize Weberian concepts and to incorporate them into a replicable body of quantitative research. Points of departure were re-examined and some new twists to Systems Theory and Structural Functionalism were considered. It was established that the demographic characteristics of both the sample and the population were similar enough for the results of this study to be generalised to the population with some degree of confidence. Much care was taken to test and validate each of the scales that comprised the questionnaire, and item analyses and factor analyses were carried out for every variable and group of variables. The measures developed in other parts of the world and by other researchers performed very well in a South African setting - as did the measures developed specifically for this study. Statistical associations and causal relationships between the various sets of variables, both at the sector level and at individual industry subgroup level, were sought by means of multiple regression analyses. Broad support was found for a 'culture-free hypothesis' that there are a number of stable relationships between organizations and their context; and these relationships will be constant in direction and strength regardless of differences in structures, or in contexts of structures between societies. Importantly, there were also a number of significant differences between this study and the findings of other studies which reflected South Africa's unique blend of developed and developing cultures and value systems. These differences provide fertile ground for future research in the field of Organization Theory. / Business Management / DBL