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In this thesis I study a model of self propelled particles exhibiting run-and tumble dynamics on lattice. This non-Brownian diffusion is characterised by a random walk with a finite persistence length between changes of direction, and is inspired by the motion of bacteria such as Escherichia coli. By defining a class of models with multiple species of particle and transmutation between species we can recreate such dynamics. These models admit exact analytical results whilst also forming a counterpart to previous continuum models of run-and- tumble dynamics. I solve the externally driven non-interacting and zero-range versions of the model exactly and utilise a field theoretic approach to derive the continuum fluctuating hydrodynamics for more general interactions. I make contact with prior approaches to run-and-tumble dynamics of lattice and determine the steady state and linear stability for a class of crowding interactions, where the jump rate decreases as density increases. In addition to its interest from the perspective of nonequilibrium statistical mechanics, this lattice model constitutes an efficient tool to simulate a class of interacting run-and-tumble models relevant to bacterial motion. Pattern formation in bacterial colonies is confirmed to be able to stem solely from the interplay between a diffusivity that depends on the local bacterial density and regulated division of the cells, in particular without the need for any explicit chemotaxis. This simple and generic mechanism thus provides a null hypothesis for pattern formation in bacterial colonies which has to be falsified before appealing to more elaborate alternatives. Most of the literature on bacterial motility relies on models with instantaneous tumbles. As I show, however, the finite tumble duration can play a major role in the patterning process. Finally a connection is made to some real experimental results and the population ecology of multiple species of bacteria competing for the same resources is considered.

The work presented in this thesis fits within the broader area of fiber optics communications. This is an important area of research as it provides a breeding ground for the present and future technologies supporting the Internet. Due to the ever-increasing bandwidth demands worldwide, the network infrastructures that make up the Internet are continuously being upgraded. This thesis aims to identify key segments of the Internet that are deemed to become the Internet's bottleneck if new technology does not replace the current one. These are datacenter intra and inter-connects, and metropolitan core area networks. In each category, we provide a comprehensive overview of the state of the art, identify key impairments affecting data transmission, and suggest solutions to overcome them.   For datacenter intra and inter-connects, the key impairments are lack of bandwidth from electro-optic devices, and dispersion. Solutions attempting to tackle these impairments must be constrained by cost and power consumption. The provided solution is MultiCAP, an alternative advanced modulation format that is more tolerable to dispersion and provides bandwidth management features, while being flexible enough to sacrifice performance in order to gain simplicity. MultiCAP was the first advanced modulation format to achieve over 100~Gb/s in 2013 for a data-center interconnect and set the world record on data transmission over a single VCSEL in 2014 for a short reach data link.    On metro-core networks, the challenge is to efficiently mitigate carrier induced frequency noise generated by modern semiconductor lasers. We point out that, when such lasers are employed, the commonly used laser linewidth fails to estimate system performance, and we propose an alternative figure of merit we name "Effective Linewidth". We derive this figure of merit analytically, explore it by numerical simulations and experimentally validate our results by transmitting a 28~Gbaud DP-16QAM over an optical link. / <p>QC 20170602</p> / GRIFFON

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The primary purpose of this paper is to analyze and evaluate a relatively recently proposed statistic, "Duncan's New Multiple Range Test," for use when the researcher's plans call for a test of significance between three or more group means.

The purpose of this study was to investigate the uses of the falsetto voice in training the male singer. Developing the upper voice is one of the most difficult problems facing the male singers. A most controversial approach to solving this problem is the use of the falsetto. The falsetto has been a subject of mystery among singers and vocal teachers for centuries. Some authorities have ignored it; some have denounced; others have greatly extolled this vocal enigma. Many myths and misconceptions surround the subject of falsetto. Even in the present age of scientific research and knowledge, there is little understanding of the falsetto--of its value and its use. The material dealing with falsetto is very brief and inconclusive in most pedagogy books. Therefore, there seemed to be a need for a systematic collection of pedagogical ideas concerning the male falsetto. This report will attempt to present all sides of the controversy.,

The recent advances in sensor and display technologies have brought upon the High Dynamic Range (HDR) imaging capability. The modern multiple exposure HDR sensors can achieve the dynamic range of 100-120 dB and LED and OLED display devices have contrast ratios of 10^5:1 to 10^6:1. Despite the above advances in technology the image/video compression algorithms and associated hardware are yet based on Standard Dynamic Range (SDR) technology, i.e. they operate within an effective dynamic range of up to 70 dB for 8 bit gamma corrected images. Further the existing infrastructure for content distribution is also designed for SDR, which creates interoperability problems with true HDR capture and display equipment. The current solutions for the above problem include tone mapping the HDR content to fit SDR. However this approach leads to image quality associated problems, when strong dynamic range compression is applied. Even though some HDR-only solutions have been proposed in literature, they are not interoperable with current SDR infrastructure and are thus typically used in closed systems. Given the above observations a research gap was identified in the need for efficient algorithms for the compression of still images and video, which are capable of storing full dynamic range and colour gamut of HDR images and at the same time backward compatible with existing SDR infrastructure. To improve the usability of SDR content it is vital that any such algorithms should accommodate different tone mapping operators, including those that are spatially non-uniform. In the course of the research presented in this thesis a novel two layer CODEC architecture is introduced for both HDR image and video coding. Further a universal and computationally efficient approximation of the tone mapping operator is developed and presented. It is shown that the use of perceptually uniform colourspaces for internal representation of pixel data enables improved compression efficiency of the algorithms. Further proposed novel approaches to the compression of metadata for the tone mapping operator is shown to improve compression performance for low bitrate video content. Multiple compression algorithms are designed, implemented and compared and quality-complexity trade-offs are identified. Finally practical aspects of implementing the developed algorithms are explored by automating the design space exploration flow and integrating the high level systems design framework with domain specific tools for synthesis and simulation of multiprocessor systems. The directions for further work are also presented.

Im Zuge der immer größer werdenden Knappheit fossiler Ressourcen und des damit verbundenen Anstiegs des Rohölpreises ergibt sich ein Trend hin zur Elektromobilität. In den nächsten Jahren werden jedoch nur Elektrofahrzeuge mit deutlich eingeschränkter maximaler Reichweite im Vergleich zu Benzin- oder Dieselfahrzeugen produziert werden können. Um den täglichen Umgang des Kunden mit einem Elektrofahrzeug trotzdem möglichst reibungslos zu ermöglichen, wurde im Rahmen dieser Arbeit eine neuartige Anzeige der verbleibenden Reichweite auf der Navigationskarte entwickelt. Nach detaillierter Analyse vorhandener Ansätze wurde je ein empirisches und ein modellbasiertes Verfahren ausgearbeitet. Die Ansätze wurden systematisch verglichen und zu einem komplett neuartigen, hybriden Ansatz kombiniert. Die auftretenden Verbräuche des Fahrzeugs werden im Kundenbetrieb erfasst, je nach Fahrsituation klassifiziert und für eine Extrapolation in der Zukunft verwendet. Die entwickelte Methodik zur Untersuchung der erreichbaren Genauigkeit ergab ein erzielbares Fehlermaß von durchschnittlich unter 10%. / Due to the prospect of a worldwide shortage of fossil fuels and the correlated increase of prices for crude-oil, a global trend to invest in electric mobility has started. During the next couple of years, electric vehicles will still have restrictions on the maximum distance that can be driven before having the need to recharge the battery. The potential costumers face the so-called „range-anxiety“, the fear to be stranded prior to reaching the destination. In order to provide a safe and easy way of operating such a vehicle, the work conducted in the course of this doctoral thesis led to a new way of displaying the remaining range of the vehicle on a navigation map. After detailed analysis of the state of the art, an empirical- and a model-based solution for calculating the remaining range were developed utilizing predictive map-data from a roadnetwork. After a systematical optimization of the developed solutions, an embedded prototype was developed which captured the driving situation of the vehicle together with the corresponding energy-consumption in order to provide a context-aware interpolation of the remaining range, depending on where the costumer would drive next. A developed methodology of objectively determining the error produced by the system resulted in a mean-deviation of 10% of absolute value.

M.Tech. (Chiropractic) / Background: In sporting activity, especially rugby, soccer, cricket and hockey, re-occurring hamstring injuries are a common sight that suggests that there is an opening for an improvement in the treatment and management of these injuries. This can be debilitating to any sportsman as it results in recurrent time away from his/her sporting activity. A study by Fyfer, Yelverton and Sher (2005), found that sacroiliac manipulation alone had a positive effect in the treatment of recurrent hamstring injuries. Cibuklka, Rose, Delitto and Sinacore (1986), proposed a possible link between hamstring muscle injuries and sacroiliac joint dysfunction. A study conducted by Donahue, Docherty and Schrader (2010), on the effects of Graston technique on pressure pain threshold, revealed a significant improvement in the patient’s pain threshold due to the fact that the instrument assisted technique effectively broke down scar tissue and correct fascial restrictions. The FAKTR approach to soft tissue dysfunction combines instrument-assisted soft tissue mobilization (Graston Technique) with proprioceptive (functional) techniques to reduce pain and return to function (Hyde and Doerr, 2012). Objective: This blinded, randomised pilot study was done to investigate the effects of sacroiliac joint manipulative therapy versus functional and kinetic treatment with rehabilitation on hamstring flexibility in previously injured hamstring muscle. Design: The study consisted of 30 participants recruited from the University of Johannesburg by word of mouth and posters, which met the inclusion criteria. They were equally and randomly divided into 2 groups. Group 1 received chiropractic therapy of the sacroiliac joint. Group 2 received functional and kinetic treatment with rehabilitation. Objective measurements consisted of digital inclinometer which measured the flexibility and range of motion of the hamstring muscle. The pressure algometry was used to measure pain pressure threshold. Procedure: Both group participants hamstring flexibility and ranges of motion were tested. Group 1 participants were motion palpated to determine sacroiliac joint dysfunction and treated with a high velocity, low amplitude trust to restricted segment, group 2 received functional and kinetic treatment with rehabilitation. Results: The statistical results should be viewed with regards that this study only represent a small group of thirty participants and therefore no assumption can be made with respect to whole population. The p-value was set at 0.05 and represents the level of significance of the results. If the p-value was less or equal to 0.05 (p≤0.05) there was a statistical significance finding. If the p-value is greater than 0.05 (p>0.05) vi there was no statistical finding. Statistical significance only means that a given result is unlikely to have occurred by chance. Analysis included demographic data analysis of age and gender. Objective data were collected using Digital Inclinometer and Pressure Algometry. Intra-group and inter-group analysis was done on straight leg raise, passive knee extension, hip extension, lateral rotation of the hip and medial rotation of the hip. The Shapiro-Wilk test was performed to determine normality. As normality could not be assumed, non-parametric testing were used to do intra-group analysis. The Non-parametric Friedman test was used to determine if a change occurred over time. As change did occur over time the Wilcoxon Signed Rank Test was use to determined where the change within each group occurred. The Mann-Whitney U test was also used to determine if any difference between the groups were present at any given time. At the end of the study both test groups showed significant clinical as well as statistical improvement over the three week course of the study. Conclusion: The FAKTR treatment did clinically have the greatest improvement, however the changes seen was not statistically superior to those seen with the sacroiliac joint manipulation treatment. A statistical significant improvement was seen in both treatment protocols, concluding that both the spinal manipulative therapy and the functional and kinetic treatment with rehabilitation could be proficient protocols in treating hamstring flexibility.

Canine cruciate ligament (CCL) rupture is a common veterinary orthopaedic problem, and has been associated with problems at the ipsilateral hip joint. However, the relationship between stifle and hip dysfunction has not been fully investigated. The purpose of this study was to establish whether CCL pathology is associated with a limitation in hip extension range large enough to affect gait. In a prospective, crosssectional study, passive and active hip extension range was determined in normal dogs as well as CCL deficient dogs. There was a significant reduction in ipsilateral passive hip extension range in the CCL deficient dogs (18.63º+/-7.57).There was a significant increase in hip extension range of the unaffected leg during gait compared to the normal group (7.03º+/-8.41). It was therefore concluded that canine CCL pathology directly affects hip extension range to a degree sufficient to affect normal gait.