This thesis contains eight chapters, dealing with machine analysis and representation. A definition and a brief survey of previous investigation devoted to shaded-pole motors and the application of finite element method for solving the two-dimensional electromagnetic field is given in Chapter 1. An outline of the present investigation is also given. In Chapter 2, the experimental requirements and details of the equipment are given. This includes the techniques of recording the transient torque patterns and the method of measuring the complete torque-speed characteristics. The experimental methods for parameters determination are also mentioned. The finite element method is outlined in Chapter 3. This chapter deals also with the assumptions made, the formulation of the non-linear energy function, the solution of Poisson's equation and an example of a simple shape contianing 16 elements for illustrating the method. In Chapter 4, the computer program for the finite element is outlined. The iteration process and the numerical representation of the magnetization curve are mentioned. Application of the finite element method to the shaded-pole motor is also given. Calculation of parameters by finite element technique is given in Chapter 5. Self inductance is calculated using the concept of stored energy and the results of self and mutual inductances are tabulated. Basic performance equations of an electrical machine are derived in Chapter 6. Solution of the basic performance equations, by a step-by-step numerical method, is also given. In Chapter 7, the steady state performance equations are established in terms of harmonic currents and inductance coefficients. The flux linkages are evaluated by the approximated functions of mutual inductances. The electromagnetic torque is calculated from the stored energy in the magentic field. General conclusions and suggestion for further work are mentioned in Chapter 8.

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This investigation is concerned with the problem of determining whether or not a significant relationship exists between body cathexis and motor performance in junior high school girls. In addition, the study investigates whether or not there are significant differences among Negro, white, and Mexican--American girls and seventh-,eighth-, and ninth-grade girls in body cathexis and motor ability performance.

The work, of which this thesis is a record, is concerned with the development of a microprocessor based system to simulate, at a speed approaching real time, the steady state and transient response of induction motor drives under various conditions. This development proceeds by outlining the basic theory involved in the simulation of induction motors. This is followed by an analysis of the various integration methods available for the solution of ordinary differential equations. This analysis being primarily concerned with determining the most efficient means of solving the set of equations used to describe induction motor response. The third part of this work explains the development of a distributed processing system that was used to achieve the simulation. This part of the work starts by describing the procedures that were followed in the development of a single processor-co-processor system and continues to detail the extension from one microprocessor to four in order to increase the speed of solution.

We know very little about how muscles and motor units in one region of the upper airway are impacted by adjustments in an adjacent airway region. In this case, the focus is on regulation of the expiratory airstream by the larynx and how changes in laryngeal aperture impact muscle motor unit activities downstream in the pharynx. We selected sound production as a framework for study as it requires (i) sustained expiratory airflow, (ii) laryngeal airway regulation for production of whisper and voice, and (iii) pharyngeal airway regulation for production of different vowel sounds. We used these features as the means of manipulating expiratory airflow, pharyngeal, and laryngeal airway opening to compare the effect of each on the activation of genioglossus (GG) muscle motor units in the pharynx. We show that some GG muscle motor units (a) discharge stably on expiration associated with production of vowel sounds, (b) are exquisitely sensitive to subtle alterations in laryngeal airflow, and (c) discharge at higher firing rates in high flow vs. low flow conditions even when producing the same vowel sound. Our results reveal subtle changes in GG motor unit discharge rates that correlate with changes imposed at the larynx, and which may contribute to the regulation of the expiratory airstream.

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A research report submitted to the Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, in partial fulfilment of the requirements for the degree of Master of Science in Occupational Therapy. Johannesburg, 2017. / Introduction Appropriate motor coordination is a prerequisite for most occupational tasks (Summers, et al., 2008) (Case-Smith & O'Brian, 2010). Young children develop motor coordination over a period of years (Case-Smith & O'Brian, 2010) (Gallahue, et al., 2012). This can be observed in the development of gross motor skills such as jumping, hopping, skipping etc. (Case-Smith & O'Brian, 2010). Delays in the development of motor coordination can thus have an effect on a child’s development in all other aspects of their life (Gallahue, et al., 2012). Problem There is a need in South Africa for a cost-effective standardised tool to evaluate motor coordination in children in a valid and reliable way. Currently standardised tools must be imported from the United States of America (USA) or the United Kingdom (UK) and may not be suitable for South African children. An evaluation tool for motor coordination does exist in South Africa, but its current scoring depends in part on the experience and skill set of the professional to judge the quality of movement during a movement task and its psychometric properties have not been explored. Aim This study aimed to identify salient behavioural characteristics that separate children with typical motor coordination development and mild to severe motor coordination dysfunction from each other on the items of the Clinical Observations of Gross Motor Items (COGMI) (SAISI, 2004), in order to provide recommendations to improve the reliability and standardization of the scoring of this tool in the 5 year 0 months – 5 years 11 months age group. Method A quantitative, comparative, descriptive, cross-sectional study design was used, with a total of 23 children in this age group. The participants were divided into a typical motor coordination (green) group and a mild to severe motor coordination dysfunction (red) group. They were videoed while performing 15 of the 18 items of the COGMI. These video recordings were analysed using movement analysis to determine specific behaviours which identify function and dysfunction in this age group. Results From the observations which could be seen when using the COGMI, clusters could be identified. As the COGMI focuses on coordination of movement rather than postures, the starting and finishing position were discarded and further analysis was only done on the movement component of items. The observations made during the movement portion of items on the COGMI were divided into observations made of the upper limbs, the lower limbs, head, neck and core. Comparisons were made between the two groups and looked at the salient behavioural characteristics that determine function and dysfunction in the age group of five year old children. Conclusion Throughout this study it was very clear that this specific age group presents with a lot of variability due to the fact that they are still developing in their gross motor skills and are not yet proficient in fundamental skills. Using these characteristics a checklist of behaviours was developed, which can be used in combination with the COGMI scoring sheet. / MT2017

Student Number : 9306442N - PhD thesis - School of Electrical and Information Engineering - Faculty of Engineering and the Built Environment / This thesis describes the design, construction and evaluation of a prototype modified tubular linear synchronous motor. The linear motor has a long static primary and a short permanent magnet mobile secondary. The design is unique in that a tubular topology has been modified to allow access to the moving secondary section. This modification means that this design can be used in long distance applications. The application for this research is the use of linear motors in rope-less vertical trans- portation systems in ultra deep level mines. The design of the linear motor has been analysed from an electrical, magnetic, mechanical and thermal perspective. Finite Element Analysis was used to predict the performance of the linear motor. The design of the secondary section has been optimised to produce the greatest possible thrust force while reducing the effects of the cogging forces. The linear motor has been tested extensively and the results correlate with theoretical predictions from the Finite Element Analysis. This project proves that the modified tubular lin- ear synchronous motor is a viable technology that can be used in rope-less vertical transportation systems.

A presença de diferenças individuais no desempenho motor de crianças e jovens da mesma faixa etária é um aspecto relatado por grande parte da literatura. O presente estudo escolheu o modelo de capacidades perceptivo-motoras para explorar estas diferenças e focou na questão de níveis diferenciados de maturação do sistema nervoso central (SNC). Uma vez que a maioria dos estudos sobre capacidades perceptivo-motoras investiga adultos e não se conhece como o nível do SNC influencia a associação entre as capacidades e desempenho motor. Com isso, o presente estudo teve como objetivo investigar a associação entre as capacidades perceptivo-motoras e o desempenho de tarefas motoras em sujeitos de 7 e 13 anos de idade. A amostra refere-se aos sujeitos que fizeram parte do estudo de Crescimento e Desenvolvimento Motor Longitudinal Misto de Muzambinho-MG. Foram selecionados 110 sujeitos, contrabalanceados em termos de sexo e idade. As capacidades perceptivo-motoras analisadas foram a de coordenação multimembros (CM), timing coincidente (TC), tempo de reação (TR) e tempo de movimento (TM), por sua vez as tarefas motoras analisadas foram correr, rebater e receber. Para a análise da correlação foi utilizado o teste de Spearman, uma vez que não houve distribuição normal. Os resultados indicaram que o desempenho do correr se associou a CM tanto para os 7 anos (ρ=-0,33) quanto para 13 anos (ρ=-0,34). Por sua vez, o desempenho do receber se associou com a CM (ρ=0,41) e TR (ρ=-0,41) para os 7 anos, mas apenas com a CM (ρ=0,29) para os 13 anos. E o desempenho do rebater não se associou com nenhuma das capacidades perceptivo-motoras analisadas. Com base nestes resultados, pode-se inferir que o desempenho em tarefas motoras típicas da infância é associado as capacidades perceptivo-motoras, mas o nível maturacional do sistema nervoso central pode ser um aspecto que interfere nesta associação. Estes resultados permitem identificar um campo de investigação promissor para entender as diferenças individuais que ocorrem no desempenho de crianças e jovens / The presence of individual differences in motor performance of children and teenagers of the same age group is a reported aspect for much of the literature. This study chose the model of perceptual-motor abilities to explore these differences and focused on issue of different central nervous system development levels (CNS). Since most of the studies investigate perceptual-motor abilities in adults and it is not known how the CNS level affects the association between ability and motor performance. This study aimed to investigate the association between perceptual-motor abilities and performance of motor tasks in individuals of 7 and 13 years old. The sample refers to subjects who participated in the study of mixed longitudinal motor growth and development in the city of Muzambinho - Minas Gerais/Brazil. It was selected 110 individuals, balanced in terms of gender and age. The perceptual-motor abilities analysed were the multilimb coordination (MC), coincident timing (CT), reaction time (RT) and movement time (TM) in turn analysed motor tasks were running, batting and receiving. For the correlation analysis it was used the Spearman\'s test, since there were no normal distribution. The results related to the running performances were associated with MC for both 7 years old (p = -0.33) and for 13 years old (p = -0.34). In turn, the receiving performances were associated with the MC (p = 0.41) and RT (p = -0.41) for 7 years old, but only with the MC (p = 0.29) for the 13 year old. Moreover, the batting performances were not associated with any of the perceptual-motor abilities analysed. Based on these results, we can infer that the performance in typical motor tasks of childhood is associated with the perceptual-motor abilities, but the maturity level of the central nervous system can be an aspect that interferes in this association. These results identify a promising field of research to understand individual differences occurring in the performance of children and teenagers

University of Macau / Faculty of Science and Technology. / Department of Electrical and Computer Engineering