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Oscillator circuits are an integral component of wireless communications systems and are increasingly in demand. As such systems gain widespread use, price becomes a very important factor in the design process, and the design cycle must be optimized. This puts an increasing emphasis on the proficiency of oscillator design automation tools. At the same time, as the performance requirements of such systems are becoming more stringent, the required simulation complexity is also increasing. More specifically, high frequency selectivity and low phase noise require very high quality factor oscillators, which in turn negatively affect the convergence performance of current simulation techniques. This thesis proposes a new continuation method for improving the convergence of oscillator simulations and compares this method to some of the methods reported in the literature. The proposed approach does not require a very good initial guess in order to converge to a final solution.

Manual cattle handling systems are widely used in South Africa. A literature review and consultations were conducted with both producers and equipment manufactures, to assess the advantages and disadvantages of various cattle handling systems with the objective of developing a more efficient system that incorporates automation, electronics and Radio Frequency Identification (RFID) technology. In this study an automated, selective sorting (RFID) based cattle handling system was developed and assessed as an alternative to the widely adopted conventional manual management system practiced in South Africa. The system is still under research and not yet available on the market. This document describes the research and development process undertaken which included planning, literature review, consultation, design, fabrication, evaluation and discussions. The RFID based system developed consists of manual, semi- and fully automated components in the form of a neck-body clamp with through access, flow control double split gates and a weigh-identification-sort system. For the ease of comparison the system was developed with a manual by-pass as a control to compare the automated and manual systems in terms of establishment cost, handling duration including identification, weighing and sorting, and operator and animal stress levels which impact on business profitability and system efficiency. Both the manual by-pass and automated RFID-based systems were evaluated. The automated system resulted in reduced handling duration, operational costs and handling stress on both operator and the animal whilst enabling selective automated sorting. The infrastructure was designed to have a capacity to handle 500 animals per day with 5 handlers and a capital investment of R200 000 was required with an operational cost of R25 000 per month. After incorporating RFID, electronics and automation of the system it was established that, on average, cattle handling duration was reduced by 63%, incorrect sorting was reduced by 5.5%, man hours were reduced by 70% with 23% and 14% less fatigue and stress levels to the handler and the animals respectively, whilst achieving efficient selective sorting. A cost benefit analysis was undertaken for both systems with the aim of assessing and determining the most profitable system. An assumption was made that the cash flow pattern remains uniform for both systems over the entire evaluation period. This revealed that the introduction of RFID based technology as an alternative to a manual based system results in an increase in business profitability by 20% and shorten the payback period by 5 years. Although there is still need to further investigate the performance parameters under different environments, it can be concluded that the introduction of RFID, electronics and automation improves the overall system technical efficiency by 32% whilst enabling efficient selective handling. / Thesis (M.Sc.Eng.)-University of KwaZulu-Natal, Durban, 2013.

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Background: The automotive industry accounts for a large part of the European economic structure. Due to both economical and environmental impacts, the industry has undergone substantial changes and companies have to increase their efficiency to stay competitive. An improvement-area, which can be directly influenced by the company is the internal material handling. A new technology that potentially supports the internal material handling process is the radio frequency identification (RFID) technology, which is perceived as a fruitful successor of the common barcoding technology. Even though the RFID technology shows multiple benefits over the barcoding technology, many companies are still reluctant to the application of the new method. The authors therefore strive to provide a deeper understanding of the following two research questions:   RQ 1: To what extent and how is RFID currently applied in the internal material handling process in the investigated automotive companies? RQ 2: For what reasons did the investigated automotive companies decide to apply or not apply RFID technologies to support their internal material handling process?   Purpose: The purpose of this thesis is to show through a multiple case study to what extent and how RFID technology is currently applied to support the internal material handling process in a number of companies in the automotive sector, both original equipment manufacturers (OEMs) and suppliers. Thereupon the main reasons for or against the application of RFID in these companies are examined.   Method: This thesis adopts a positivistic perspective and a deductive approach. It is designed as a qualitative multiple case study carried out in four different companies with five different plants in the automotive industry. Empirical data was gathered through interviews. The analysis is based on primary as well as secondary data.   Conclusions: Throughout the course of the study it became apparent that the RFID technology is on the radar of all investigated companies. Only Scania Zwolle, Volvo Skövde and Bosch Homburg apply the technology and see concrete benefits in the usage of RFID above barcoding. The extent of application here differs from a large scale to a small scale. The three companies name benefits such as an improved automatic tracking & tracing system with improved real-time data quality and a reduction in costs, which is mainly achieved through a reduction of manual labour. Additionally they face benefits, which are business-specific such as the possibility for automatic alerts throughout the internal material handling process at Scania Zwolle, the need for a ‘silent’ successor over barcoding at Volvo Skövde and a supporting tool for their lean management program at Bosch Homburg. VDL Nedcar Born and Scania Oskarshamn in turn name concrete reasons for not applying the technology. VDL Nedcar Born is undergoing substantial changes in their production facility which currently has priority and Scania Oskarshamn does not see benefits that outweigh the high costs for the RFID technology.

The world, especially the business world, has changed from consisting of different countries and markets to one global market. This can be attributed to better transportation, communication and information systems. This new development has changed the rules of the business game. No more do companies compete with local players only but increasingly with foreign based entities. Many experts argue that top companies in the world today are those that have embraced new technologies to improve their entire operations. New information technology allows them to integrate their operations upstream with their suppliers, downstream with their clients as well as in-house to improve their efficiencies. This includes mining companies who have to introduce new information, communication and transportation systems to compete with their global counterparts. This study investigates the operation of South African underground mines operation. This is done with a focus on the integration of tracking technology into the horizontal transportation system. The objective is to improve productivity due to better process control. In order to achieve this objective the entire operational process had to be divided into key elements that had to be investigated. The following key elements were identified and investigated: Information and communication strategy, Organisation structure, Departmental integration, Organisational processes, Management information, Information management, Management information system, Solution selection criteria, Causes of low productivity, Problems with logistics system, Technology implementation methods, Outsourcing, Reasons for technology failure and Future challenges facing industry. The investigation was done in four phases. The first phase provided a framework for a literature study. The second phase comprised a literature study that would set the foundation for the empirical study. The third phase consisted of the empirical study, research methodology and data gathering. The fourth and final phase consisted of data grouping and analysis, conclusions and recommendations. Among the conclusions drawn, the following stand out: There is a general problem in the industry that can be attributed to logistics. There is also a problem of information quality and information flow among the different departments that lead to poor integration. Another problem that was highlighted is the non-involvement of end-users in technology selection and implementation. In terms of future challenges facing the industry, poor education levels, productivity and commodity prices were identified. In terms of solutions for the future, integrating technology, with the involvement of end users, were mentioned. All these findings were uniform across the different mining houses, which show the similarity of the industry culture. / Thesis (M.B.A.)--North-West University, Vaal Triangle Campus, 2009.

The world, especially the business world, has changed from consisting of different countries and markets to one global market. This can be attributed to better transportation, communication and information systems. This new development has changed the rules of the business game. No more do companies compete with local players only but increasingly with foreign based entities. Many experts argue that top companies in the world today are those that have embraced new technologies to improve their entire operations. New information technology allows them to integrate their operations upstream with their suppliers, downstream with their clients as well as in-house to improve their efficiencies. This includes mining companies who have to introduce new information, communication and transportation systems to compete with their global counterparts. This study investigates the operation of South African underground mines operation. This is done with a focus on the integration of tracking technology into the horizontal transportation system. The objective is to improve productivity due to better process control. In order to achieve this objective the entire operational process had to be divided into key elements that had to be investigated. The following key elements were identified and investigated: Information and communication strategy, Organisation structure, Departmental integration, Organisational processes, Management information, Information management, Management information system, Solution selection criteria, Causes of low productivity, Problems with logistics system, Technology implementation methods, Outsourcing, Reasons for technology failure and Future challenges facing industry. The investigation was done in four phases. The first phase provided a framework for a literature study. The second phase comprised a literature study that would set the foundation for the empirical study. The third phase consisted of the empirical study, research methodology and data gathering. The fourth and final phase consisted of data grouping and analysis, conclusions and recommendations. Among the conclusions drawn, the following stand out: There is a general problem in the industry that can be attributed to logistics. There is also a problem of information quality and information flow among the different departments that lead to poor integration. Another problem that was highlighted is the non-involvement of end-users in technology selection and implementation. In terms of future challenges facing the industry, poor education levels, productivity and commodity prices were identified. In terms of solutions for the future, integrating technology, with the involvement of end users, were mentioned. All these findings were uniform across the different mining houses, which show the similarity of the industry culture. / Thesis (M.B.A.)--North-West University, Vaal Triangle Campus, 2009.

The focus of this thesis is to investigate the implementation of Radio Frequency (RF) In-Phase and Quadrature-Phase (I/Q) vector modulation through the use of modern photonic components and sub-systems which offer extremely wide RF intrinsic bandwidths. All-electronic vector modulators suffer from frequency coverage limitations and amplitude and phase instability due to components such as phase shifters and variable gain controllers operating at or near 100\% bandwidth. In stark contrast, once an RF signal has been modulated onto an optical carrier, the percent bandwidth of the RF to carrier is typically less than 0.01\% percent. The fundamental mechanisms and basic electronic and photonic components needed to achieve vector modulation is introduced first. The primary electrical component required in most architectures is the 90° RF hybrid coupler, which is required to generate the RF I and Q terms. The two primary photonic building blocks, aside from the laser, electro-optic modulator and demodulator, are Mach-Zehnder Modulators (MZM) and Variable Optical Attenuators (VOA). Through the utilization of these components, multiple past architectures are explored and multiple new architectures are designed simulated. For each architecture, there is a discussion on the practical implementation. Considerations such as system complexity, integration, and sensitivity to unwanted environmental stimuli are taken into account with potential solutions to alleviate these risks. In closing, the noise figure and its impact on Spur-Free Dynamic Range (SFDR) for a basic RF photonic link is derived to provide a system-level figure of merit that can be used, in most RF applications, to determine the overall performance utility current and future designs.