Novel atomic force microscope (AFM) probes with integrated thin film thermal sensors are presented. Silicon micromachining and high resolution electron beam lithography (EBL) have been used to make batch fabricated, functionalised AFM probes. The AFM tips, situated at the ends of Si3N4 cantilevers, are shaped either as truncated pyramids or sharp triangular asperites. The former gives good thermalisation of the sensor to the specimen for flat specimens whereas the latter gives improved access to highly topographic specimens. Tip radii for the different probes are 1 m and 50 nm respectively. A variety of metal structures have been deposited on the tips using EBL and lift-off to form Au/Pd thermocouples and Pd resistance thermometer/heaters. Sensor dimensions down to 35 nm have been demonstrated. In the case of the sharp triangular tips, holes were etched into parts of the cantilever in order to provide self alignment of the sensor to the tip. On the pyramidal tips it has been shown that multiple sensors can be made on a single tip with good definition and matching between sensors. A conventional AFM was constructed in order to test the micromachined thermal probes. During scans of a photothermal test specimen using improved access thermocouple probes, 80 nm period metal gratings were thermally resolved. This is equivalent to a thermal lateral resolution of 40 nm. Pyramidal tips with a resistance thermometer/heater, which were made for the microscopy and analysis of polymers, have been showed by others to produce high resolution thermal conductivity images. The probes have also been shown to be capable of locally heating a polymer specimen and thermomechanically measuring phase changes in small volumes of material. Also presented here is a study of scanning thermal microscopy of semiconductor structures using a commercial AFM. Included are scans of several specimens using both commercial andthe new micromachined probes. Subsurface images of voids buried under a SiO2 passivation layer were taken. It is shown that contrast caused by thermal conductivity differences in the specimen may be detected at a depth of over 200 nm.

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As electric utilities move into more competitive generation supply regimes, with limited scope to expand transmission facilities, the optimisation of existing transmission corridors for power transfer becomes of paramount importance. In this scenario, Flexible AC Transmission System (FACTS) technology, which aims at increasing system operation flexibility, appear as an attractive alternative. Many of the ideas upon which the foundations of FACTS rest were conceived some time ago. Nevertheless, FACTS as a single coherent integrated philosophy is a newly developed concept in electrical power systems which has received the backing of the major manufacturers of electrical equipment and utilities around the world. It is looking at ways of capitalising on the new developments taking place in the area of high-voltage and highcurrent power electronics in order to increase the control of the power flows in the high voltage side of the network during both steady state and transient conditions, so as to make the network electronically controllable. In order to examine the applicability and functional specifications of FACTS devices, it is necessary to develop accurate and flexible digital models of these controllers and to upgrade most of the software tools used by planners and operators of electric power systems. The aim of this work is to develop general steady-state models FACTS devices, suitable for the analysis of positive sequence power flows in, large-scale real life electric power systems.Generalised nodal admittance models are developed for the Advance Series Compensator (ASC), Phase Shifter (PS), Static Var Compensator (SVC), Load Tap Changer (LTC) and Unified Power Flow Controller (UPFC). In the case of the ASC, two models are presented, the Variable Series Compensator (VSC) and the Thyristor Controlled Series CapacitorFiring Angle (TCSC-F A). An alternative UPFC model based on the concept of Synchronous Voltage Source (SVS) is also developed. The Interphase Power Controller (IPC) is modelled by combining PSs and VSCs nodal admittance models. The combined solution of the power flow equations pertaining to the FACTS devices models and the power network is described in this thesis. The set of non-linear equations is solved through a Newton-Rapshon technique. In this unified iterative environment, the FACTS device state variables are adjusted automatically together with the nodal network state variables so as to satisfy a specified nodal voltage magnitudes and specified power flows. Guidelines and methods for implementing FACTS devices and their adjustments within the Newton-Rapshon algorithm are described. It is shown that large increments in the adjustments of FACTS devices and nodal network state variables during the backward substitution may dent the algorithm's quadratic convergence. Suitable strategies are given which avoid large changes in these variables and retain the Newton-RapshRapshon method's quadratic convergence. The influence of initial conditions of FACTS devices state variables on the iterative process is investigated. Suitable initialisation guidelines are recommended. Where appropriate, analytical equations are given to assure good initial conditions.

As CMOS device dimensions are being aggressively scaled, the device characteristic must be assessed against fundamental physical limits. Nanoscale device modelling and statistical circuit analysis is needed to provide designer with ability to explore innovative new MOSFET devices as well as understanding the limits of the scaling process. This work introduces a systematic simulation methodology to investigate the impact of intrinsic parameter fluctuation for a novel Ultra-Thin-Body (UTB) Silicon-on-Insulator (SOI) transistor on the corresponding device and circuits. It provides essential link between physical device-level numerical simulation and circuit-level simulation. A systematic analysis of the effects of random discrete dopants, body thickness variations and line edge roughness on a well scaled 10 nm, 7.5 nm and 5 nm channel length UTB-SOI MOSFET is performed. To fully realise the performance benefits of UTB-SOI based SRAM cells a statistical circuit simulation methodology which can fully capture intrinsic parameter fluctuations information into the compact model is developed. The impact of intrinsic parameter fluctuations on the stability and performance of 6T SRAM has been investigated. A comparison with the behaviour of a 6T SRAM based on a conventional 35 nm MOSFET is also presented.

This portfolio thesis documents the work undertaken by the author under the auspices of the Engineering Doctorate (EngD) programme. The research work undertaken was completed at the sponsoring company, A2E Limited. There is a wide range of products and solutions to meet both commercial and personal electronic storage needs. This work documents research and development over a four year period into algorithms, implementations and product development for novel storage solutions for commercial and personal use. The design work and technical and business objectives were guided by the sponsoring company, A4E limited. This portfolio thesis considers the storage market at the start of the project, the commercial and technical aspects relevant to this market place and describes the development and testing of a RAID 6 algorithm in both hardware and software. The key contributions presented in this portfolio thesis include the implementation of the smallest and fastest FPGA based Reed-Solomon RAID 6 hardware accelerator. We also present the first commercial implementation of a Reed-Solomon RAID 6 intellectual property (IP) block. Both the hardware and software implementation are discussed in detail along with the supporting IP blocks and device drivers. Documentation of the product development stages and additional project work carried out to provide an understanding of product development stages and the requirements placed during such work are also examined. the results of testing and implementation are considered and the performance of the proposed solution is considered along with the commercial viability and success of the project.

<p> The purpose of this case study, was to conduct research that provided an in-depth understanding of the 1-1 implementation of iPads into the senior class of two four-year charter high schools in Southern California. The problem addressed was the following: to date, there has been little definitive research to examine what works and what did not seem to work in the implementation of iPads into high school classrooms. This study describes the experiences and reflections of the participants during their first year of implementing the iPads. The participants included: administrators, staff and faculty at both schools who were interviewed, and students over the age of 18 during the last weeks of their senior year who completed an online electronic survey. All of these participants had experience with the iPad in a 1-1 setting for the 2012&ndash;2013 school year. </p><p> This study found that the culture of the school created a rich learning environment, due to the trust between participants formed from their communities of practice, which allowed for resilience in the participants while they experimented with the iPad implementation. There were more meaningful interactions between students and faculty, and the participants did not desire, or require, formal professional development. There were potential &ldquo;green&rdquo; benefits from working digitally and a &ldquo;cool&rdquo; factor that helped to engage participants. In conclusion, the culture of the school as pioneers and the shared vision of the participants, along with the nature of their training, were the factors that contributed to the success of this iPad implementation. </p>

<p> Smartphones, now so ubiquitous that almost every American adult carries one, bring major changes not just to the way people gather and exchange information but also to the way in which they interact with one another and with the organizations to which they belong. A variety of research indicates that while it unleashes remarkable creativity and productivity, this complex, entangled phenomenon also has subtle, worrying implications. This study focused on those dynamics in one unit of the United States Army. Scharmer's Theory U as well as the systems theory espoused by Gharajedaghi and Ackoff guided this research. The research question asked, <i>What are the most important aspects of the holistic smartphone user experience in an Army work environment? </i> This phenomenological study was based on interviews with 28 military personnel of a variety of ages, ranks, and duty positions. While the findings were generally consistent with other research into smartphone use in society, it is clear that smartphone use is inextricably linked to a number of complex challenges for the leaders of the military unit studied. In particular, the paradoxical aspects of smartphone use which, while clearly beneficial, also foster tension, complexity, stress, and anxiety. More concerning is the finding that smartphone use jeopardizes the development of the traditional interactive and collaborative culture of the unit. Finally, current policies related to the use of smartphones inadequately address the issues and concerns expressed by respondents. The results of the study, therefore, serve as a call to action for unit leaders. They offer a compelling case for transformative change and leader attention and intention so that smartphone use can continue to enhance creativity and productivity while optimizing organizational development in the emerging future.</p>

The value of an IT system can be considered from a number of different perspectives. Specifically, the same IT system can be valued differently across different stakeholders, time periods, usage environments, and other contextual factors. When measuring the value of an IT system, it is important to consider what value perspectives are relevant and how those perspectives affect the development of value metrics. An IT value assessment framework is proposed to aid in identifying such contextual factors and exploring how those factors affect the value that is realized from an IT system.

The measurement of ankle joint dorsiflexion is an important component of the clinical examination of the foot and is also an outcome measure often employed in research. Diagnosis of ankle equinus or limited ankle dorsiflexion is based solely on this measurement. Although a great majority of research papers in this field utilise normal clinical goniometers for obtaining the maximum ankle dorsiflexion angle (MADA) and important clinical decisions are based on these findings, there is overwhelming evidence that this method is highly unreliable. Thus this thesis aimed to investigate alternative methods of measuring ankle dorsiflexion and various issues that affect the MADA in order to obtain a clear picture of foot segment movement from which an Ankle Goniometer could be consequently designed and validated. Ten different techniques were identified that included various apparatuses designed specifically for measuring ankle dorsiflexion. However, during validation, their methodological quality would have benefitted from the use of an actual patient population and comparison with a reference standard, which caused papers to score poorly on methodological quality assessment. It was concluded that issues affecting this measurement and that needed to be researched further include: foot posture, the amount of moment applied and the stretching characteristics of the calf muscle tendon unit. Experiments within this study indicated that in adults, the mean maximum pronated angles were always higher than in other postures, with 8.27o difference between the pronated and supinated postures (p=0.032) and 5.78o between pronated and neutral (p=0.000). However, the reported difference between neutral and supinated (mean angle of 2.49o) is of little clinical significance. It was observed that the forefoot always travels through a greater angle than the hindfoot in all 3 foot postures, while the hindfoot to forefoot angle increases during the application of a moment, indicating that the ‘midtarsal joint locking mechanism’ cannot be applied to passive dorsiflexion of the foot. In adolescents, there are no significant differences in the mean MADA between the 3 postures, implying that this measurement technique may be performed in any of these postures. It was also concluded that there is no need to control moment applied during this measurement procedure to produce consistent results between raters and that the calf muscle tendon unit does not stretch significantly following brief repetitive passive stretching. ii An ankle goniometer that measured purely hindfoot movement by eliminating forefoot influence and that increased reliability by holding the foot in the chosen posture, was consequently designed. This was validated by synchronizing with an electrogoniometer and an optoelectronic motion capture system. Reliability testing, with the foot held in a supinated posture as opposed to the traditional Rootian method of placing the foot at subtalar joint neutral position, spanned a number of different trials, including intra-tester and inter-tester reliability studies utilising both controlled and uncontrolled conditions, in convenience samples of healthy participants and a random sample of patients. Reliability testing between 4 raters with little experience on the utilization of this device was finally conducted. It has been shown that the Ankle Goniometer is a valid and reliable device for measuring ankle joint complex dorsiflexion both in healthy adults and in a patient population.

This thesis will describes how microfabrication techniques can be combined with Atomic Force Microscopy (AFM) to investigate the potential for cellular elasticity to be used as an indicator of cell behaviour and responses to chemical and topographical surface modifications. To this end, a robust and reliable AFM protocol has been developed to take in to account the many changeable parameters encountered when performing live cell indentation measurements. Complimented with traditional molecular biological methods, such as immunofluorescence staining and confocal microscopy, the biomechanical properties and functions of cells have been investigated to see how they respond to simple chemical and topographical cues. Simple surface topographies have frequently been exploited to learn more about cell behaviour and subsequent function however the mechanisms by which the cells senses the surrounding cues and interprets them accordingly has remained somewhat unknown. It is the hypothesis of the work presented here that the arrangement of the internal cytoskeleton as influenced by external factors in responsible for the transmission of tensile strength to the cytoplasm and on to the nuclear membrane. This in turn has the potential to alter transcription within the nucleus ultimately affecting over all cell function.