Thesis (MSc (Physiology))--University of Stellenbosch, 2000. / 251 leaves single sided printed, preliminary pages and numbered pages 1-151. Includes bibliography, list of appendixes, abbreviations, variables, figures and tables. Digitized at 300 dpi (OCR), using a Bizhub 250 scanner. / ENGLISH ABSTRACT: The Whistle Watch™, an innovative and commercialised peak flow monitor, inspired this study, with its abnormal and complex measuring behaviour. The Whistle Watch™ latter is an audible peak flow monitor with a threshold-activated whistle as the essential component. The whistle is calibrated for a certain flow, and then encased in a body with a variable exhaust valve to atmosphere. Using the Whistle Watch™, with the exhaust valve pre-set, executing a forced expiratory effort, the audible notification of the whistle would indicate a stable asthmatic condition at that setting. No audible notification would result in the use of medication as a preventative measure. Due to the absence of existing theories and literature on the mechanics of whistles, the Whistle Watch™ was empirically developed. This study therefore, focuses on the characterisation and consequent improved understanding ofthe mechanics ofa whistle, with the objective to monitor pulmonary function in a novel way. During this study, a novel technique was developed to determine the reed activation point, or onset of oscillation, in terms of pressure. This technique was then implemented throughout the study. The initial observation and experimentation underlined the whistle's activation sensitivity towards any irregularities of the reed surface. A statistical spread of reed activation pressures defined the reed's inherent non-linear properties. A high dependence of reed activation towards upstream geometry was noted, and a clarification hypothesis was formulated. The effect of reed dimensions on activation pressure was exposed as a complex unexplored field. Existing mathematical reed theories only accommodate steady state oscillations, whereas the completed study indicated a high sensitivity of the reed activation pressure towards different input envelopes. This sensitivity was encapsulated in a mathematical model, with initial support and proofprovided by a previous independent study. All the observed effects and phenomena had far reaching practical application towards the production and quality control ofthe Whistle Watch™. / AFRIKAANSE OPSOMMING: Whistle Watch™, 'n inoverende, kommersieel piekvloeimonitor, was die inspirasie vir die studie, deur sy abnorrnale en ingewikkelde meet-gedragskenrnerke. Laasgenoemde is 'n piekvloeimonitor met 'n fluit wat geaktiveer word by 'n vooraf vasgestelde drempel. Die fluit word gekalibreer vir 'n bepaalde vloei, waarna dit geenkapsuleer word in 'n hoofdeel met 'n veranderlike uitlaat na die atmosfeer. By die gebruik van die Whislte Watch™, met die uitlaatklep gestel op 'n voorafbepaalde vloeitempo, word 'n bepaalde ekspirasievlak verkry. Hierdie vlak het 'n hoorbare kennisgewing tot gevolg, wat 'n stabiele asmatiese toestand aandui. In die afwesigheid van 'n hoorbare respons, word medikasie as voorkornende rnaatreel vereis. Die Whislte Watch™ is empiries ontwikkel in die afwesigheid van bestaande teoriee en literatuur ten opsigte van die werking van fluite. Die fokus van hierdie studie word dus geplaas op die karakterisering van die werking van fluite, wat 'n beter begrip tot gevolg het. 'n Nuwe benadering tot die monitering van die pulrnonere funksie is dus haalbaar. Tydens die studie is 'n unieke tegniek ontwikkel om die aktiveringspunt van die riet, of die aanvang van ossilasie in terrne van druk, te bepaal. Hierdie tegniek is toe dwarsdeur die studie geiinplimenteer. Die fluit se aktiveringssensitiwiteit, in terrne van die oppervlak-onreelmatighede, van die riet was duidelik waarneembaar. Die inherente nie-liniere eienskappe van die riet is duidelik waarneembaar in rietaktiveringsdrukke. 'n Verklarende hipotese is as gevolg van 'n afhanklikheid van die rietaktiveringsdrukke relatief tot stroom-op geometrie, gestel. Die effek wat rietafinetings op aktiveringsdrukke het, was blootgel~ as 'n komplekse onontwikkelde gebied. Bestaande wiskundige rietteoriee maak slegs voosiening vir nie-fluktuerende ossilasies. Na voltooiing van hierdie studie is dit duidelik dat daar wei 'n hoe sensitiwiteit van die rietaktiveringsdrukke bestaan, met verwysing na verskillende ekspiratoriese profiele. Hierdie sensitiwiteit word vervat in 'n wiskundige model met toepaslilke ondersteuning en bewyse uit 'n vorige, onathanklike studie. Aile waarneembare phenomena het resulterende praktiese impakte ten opsigte van die produksie en gehalteversekering van die Whistle Watch™.

The Compact Linear Collider (CUC) is a proposed electron-positron collider with a centre- of-mass energy of 0.5 to 5 TeV, optimised for a nominal centre-of-mass energy of 3 TeV, at high luminosities exceeding 1034 cm-2s-J. The high beam charges in the CUC beams make classical techniques for measuring the transverse beam size such as optical transition radiation (OTR) screens or wire scanners very difficult, which necessitates the use of non-invasive beam- size monitors. The laser-wire is a system that meets these requirements; it uses inverse Compton scattering to determine transverse beam-sizes by scanning a laser beam across the electron beam. This thesis describes how such a laser-wire system was installed and operated at PETRA-III at DESY, which uses an automated mirror to scan a Q-switched laser pulse across the electron beam and is developed from the system previously operated at PETRA-II. The measurements of key performance parameters are described and used in determining the emittance of the PETRA-III beam. The thesis includes a detailed investigation of the laser .' system as well as the collision measurements. Furthermore, simulations were carried out to design a similar system for the proposed transfer line of the CUC Drive-Beam and the necessary baseline characteristics of such a system are described.

A Thesis submitted to The University of Arizona College of Medicine - Phoenix in partial fulfillment of the requirements for the Degree of Doctor of Medicine. / Obstructive sleep apnea (OSA) is a condition characterized by upper airway obstruction during sleep causing intermittent hypoxia and nighttime awakening. It is a common condition in the United States that is often undiagnosed. It is a significant risk factor for decreased daytime productivity, quality of life, cardiovascular disease, and death. The current gold standard for diagnosis of OSA is laboratory‐based polysomnography (PSG). While PSG is necessary for the diagnosis and monitoring of OSA, many patients have limited access to PSG due to wait times at PSG laboratories or economic or geographic limitations. Portable sleep monitoring has been studied as a possible solution for patients who do not have access to timely PSG. This study aimed to use the Zephyr BioHarness 3, a chest‐worn physical activity monitor that records movement and physiologic data in real‐time, to detect apnea events in patients with suspected OSA undergoing single‐night laboratory PSG. Twenty patients underwent single‐night laboratory‐based PSG while simultaneously wearing the Zephyr BioHarness 3. The Zephyr BioHarness 3 data was analyzed using three methods. First, apnea events were identified in 10‐second windows of Zephyr data via support vector machine, logistic regression, and neural network (sensitivity = 76.0 ± 0.3%, specificity = 62.7 ± 0.2%, accuracy = 63.7 ± 0.1%). Second, apnea events were identified using the mean, median, and variance of the 10‐second windows (sensitivity = 72.3 ± 0.3%, specificity = 69.4 ± 0.1%), accuracy 69.6 ± 0.1%). Third, apnea events were identified using phase‐space transformation of the Zephyr BioHarness 3 data (sensitivity = 76.9 ± 0.3%, specificity = 77.9 ± 0.1 %, accuracy = 77.9 ± 0.1%). The Zephyr BioHarness shows initial promise as a possible OSA screening tool for patients suspected of OSA but who lack access to timely laboratory‐based PSG.

A low cost Heart Beat Monitoring device (HBMD) for detecting heart beat in beats per minute is presented in this thesis. An optical technique called “Photoplethysmography” is utilized by attaching to the base of the finger for monitoring beat to beat pulsation. Two major design issues addressed in this research is to achieve a strong and accurate PPG signal and simultaneously minimizing physiological artefacts and interference. In order to achieve the aim and objectives of the research, this thesis thoroughly explores two new signal conditioning hardware designs. Firstly is the design and fabrication of a low cost reflectance mode PPG heart monitor using parallel port interfacing and secondly are the design and development of a portable transmission mode PPG heart monitor using microcontroller PIC16F84A and PIC16F87. Both PPG heart monitor design is divided into three phases. First is the detection of weak pulses through the fingertip. The PPG signal is then amplified, filtered and digitized by the signal processing unit. Finally the heart rate is calculated, analyzed and displayed on the computer using parallel port interface and on the liquid crystal display using microcontroller PIC16F87. A comprehensive circuit design and analysis work was implemented verified by Proteus VSM circuit simulations and laboratory experiments. Data is presented from the method comparison study in which heart rates measured with the reflectance mode PPG and portable transmission mode PPG heart monitor were compared with those measured with standard techniques on 13 human subjects. Benchmarking tests with approved pulse oximeter and blood pressure monitor Omron M6 reveals that the PPG heart monitor is comparable to those devices in displaying the heart rate. It is also verified through experiments that both PPG heart monitor design fulfill the objectives, including achieving strong and accurate PPG signal, reduction in physiological artefacts and interference and financially low in cost. As the conclusion, the current version of the reflectance mode PPG and portable transmission mode PPG heart monitor successfully measure heart rates fast and reliably in most subjects in different body position. The PPG heart monitor proposed avoid the need to apply electrodes or other sensors in the correct position which directly minimizes the preparation time drastically. This makes the PPG heart monitor more attractive for heart monitoring purpose and its advantage should be explored further.

Master of Science / Department of Industrial and Manufacturing Systems Engineering / Shing I. Chang / This research studies a few methodologies for real-time detection of wave profile changes. In regular profile monitoring, change detection takes place at the end of time period when a complete profile is available. In real-time change detection of profiles, a potential profile change takes place between the beginning and the end of the time period. The decision involves the identification whether a process is in control or out of control before the entire profile is generated. In this regard, five proposed methodologies were developed and tested in this thesis. Earthquake waves, manufacturing processes, and heart beat rate are a few examples of profiles with different natures that the proposed methodologies can be applied to. Water temperature profiles generated during a curing process are considered as an example in this study. Successful implementation of the proposed work on these profiles would cause saving great amounts of time and money. Five methods are studied for monitoring the water control process of a curing process. The first four proposed methodologies are based on an univariate approach where the statistic used for process monitoring is the enclosed area between the profiles and their fitted cutting lines. A multivariate approach is also proposed. A simulation study is also conducted when the best method is chosen based on it performance and simplicity of operations. Various types of acceptable and unacceptable profiles are simulated for the best proposed method identified in the preliminary study. The best method has a satisfactory performance in detecting the changes in the unacceptable profiles. In addition, the false alarm rate in identifying acceptable profiles as bad profiles is lower than 10%.

A verificação de forma independente do cálculo de dose e de unidades monitoras num plano de tratamento de IMRT é um passo importante nos procedimentos de garantia de qualidade da técnica em questão. Atualmente este verificação é baseada apenas em medidas experimentais demoradas e trabalhosas. Neste trabalho foi desenvolvido uma metodologia de cálculo de unidades monitoras de forma independente como uma nova ferramenta para garantir a qualidade e exatidão dos tratamentos de IMRT. Os valores encontrados se aproximam bastante dos valores calculados pelo sistema de planejamento utilizado, de forma que o algoritmo de cálculo desenvolvido apresentou uma concordância dentro de ± 1,8 % para uma geometria simples. Após diversos testes e com os níveis de ação devidamente estabelecidos, a verificação independente da unidade monitora para planos de tratamento de IMRT se tornará uma ferramenta efetiva e eficiente no controle de qualidade que ajuda a identificar e reduzir possíveis erros de tratamento em radioterapia. Como contribuição original deste trabalho, assegura-se aos serviços de Radioterapia a utilização da metodologia desenvolvida como ferramenta de controle de qualidade em tratamentos com IMRT. Em especial aos serviços que não dispõem de recursos econômicos para adquirirem softwares comercialmente disponíveis para o cálculo independente da unidade monitora. / Independent verification of dose calculations and monitor units settings of IMRT treatment plans is an important step in the quality assurance procedure for IMRT technique. At present, the verification is mainly based on experimental measurements, which are time consuming and laborious. In this work an independent methodology of monitor units calculation was developed as a new tool for IMRT treatments quality and precision assurance. The values found are near those calculated by the treatment planning system used, in a manner that the calculation algorithm demonstrated ± 1,8 % concordance in a simple geometry with the system. After several tests and the levels of action well established, the independent monitor units verification for IMRT treatment plans will become an effective and efficient tool in quality assurance, helping identification and the reduction of possible mistakes in radiotherapy treatments. To radiotherapy services is assured the use of the developed methodology as a tool of quality control in IMRT treatments as an original contribution of this work, specially those that do not dispose financial resources to acquire commercially available independent monitor unit calculus software.

A verificação de forma independente do cálculo de dose e de unidades monitoras num plano de tratamento de IMRT é um passo importante nos procedimentos de garantia de qualidade da técnica em questão. Atualmente este verificação é baseada apenas em medidas experimentais demoradas e trabalhosas. Neste trabalho foi desenvolvido uma metodologia de cálculo de unidades monitoras de forma independente como uma nova ferramenta para garantir a qualidade e exatidão dos tratamentos de IMRT. Os valores encontrados se aproximam bastante dos valores calculados pelo sistema de planejamento utilizado, de forma que o algoritmo de cálculo desenvolvido apresentou uma concordância dentro de ± 1,8 % para uma geometria simples. Após diversos testes e com os níveis de ação devidamente estabelecidos, a verificação independente da unidade monitora para planos de tratamento de IMRT se tornará uma ferramenta efetiva e eficiente no controle de qualidade que ajuda a identificar e reduzir possíveis erros de tratamento em radioterapia. Como contribuição original deste trabalho, assegura-se aos serviços de Radioterapia a utilização da metodologia desenvolvida como ferramenta de controle de qualidade em tratamentos com IMRT. Em especial aos serviços que não dispõem de recursos econômicos para adquirirem softwares comercialmente disponíveis para o cálculo independente da unidade monitora. / Independent verification of dose calculations and monitor units settings of IMRT treatment plans is an important step in the quality assurance procedure for IMRT technique. At present, the verification is mainly based on experimental measurements, which are time consuming and laborious. In this work an independent methodology of monitor units calculation was developed as a new tool for IMRT treatments quality and precision assurance. The values found are near those calculated by the treatment planning system used, in a manner that the calculation algorithm demonstrated ± 1,8 % concordance in a simple geometry with the system. After several tests and the levels of action well established, the independent monitor units verification for IMRT treatment plans will become an effective and efficient tool in quality assurance, helping identification and the reduction of possible mistakes in radiotherapy treatments. To radiotherapy services is assured the use of the developed methodology as a tool of quality control in IMRT treatments as an original contribution of this work, specially those that do not dispose financial resources to acquire commercially available independent monitor unit calculus software.

This thesis describes empirical research into project management of software development. Specifically, the aim of the research is to investigate how project managers monitor, control and coordinate software development tasks and how this is affected by changing environments, in this case increased organizational distance between the project manager and elements of the project team. Differing project environments allow investigation into which project management mechanisms are essential, which are required in specific circumstances and which may be useful but not necessarily essential. To explore how software development projects are monitored, controlled and coordinated, a broad range of literature from software development and other fields such as organization theory, supply chain management and automobile manufacture is examined to establish a consensus of the mechanisms of project monitoring, control and coordination and their classification into groups. To better understand how the different mechanisms may be selected in different circumstances, a range of contingencies is examined to deduce which of these contingencies may significantly affect the project management of software development projects. Outsourced and distributed software development projects are becoming more frequent than in the past with consequent effects on project management practices. Although there has been some research into the ways in which project managers monitor, control and coordinate software development projects, little of it has investigated how the mechanisms employed to do so may be affected by such factors as increasing organizational distance. If more were known about the ways in which changed project environments affected the selection and use of project management mechanisms, better responses to those environmental changes could be devised. This could also identify where tools could be developed to assist project management of outsourced and distributed projects. In this research, the term 'organizational distance' is used to describe the cultural, structural and administrative distance between the project manager and elements of the project team. Since there is limited information available on the concept of organizational distance, a new model is developed that encompasses the dimensions of distance that may be found in outsourced or globally distributed projects. A second model is then developed that relates changes in the factors of organizational distance with preferred choices of project management mechanism via project contingencies. Empirical data were collected by structured interviews with project managers who were currently engaged in software development within Sydney, Australia. The method of collecting the data provided both quantitative and qualitative data that enabled three separate ways to investigate the research questions. The empirical research found that project managers do not rely on a single mechanism to monitor, control or coordinate a software development project but employ multiple mechanisms. While the portfolio of mechanisms for both monitoring and control comprised a relatively narrow selection, the portfolio of coordination mechanisms was more diverse. Project monitoring mechanisms were employed to first detect any project problems then to respond to those problems. This contrasts with monitoring systems designed to provide all the information about both the existence and probable causes of project problems. Project control mechanisms reflected the origin of the control. The constraints imposed on the project by the organization and used by the project manager to direct the project tended to be outcome related, for example budget and schedule. The behaviour of the project team, even across significant organizational distances, was controlled through the use of project plans that determined when different tasks would be performed. Project coordination mechanisms reflected the different types of dependencies between software development activities. The most common was using a project work breakdown structure, expressed in the project schedule, to resolve sequential and pooled resource dependencies. Mutual dependencies tended to be resolved using interactive mechanisms such as co-location, conversations and meetings. The empirical evidence did not find any difference between co-located projects and distributed projects so far as the choice of project management mechanisms were concerned. Distributed and globally outsourced software development projects may encounter many difficulties that a fully co-located project does not, but the response to those difficulties appears to lie with the implementation of project management mechanisms and not their selection.

<p>Physical activity (PA) is likely to constitute an important aspect of health-related behaviour in growing children. However, the knowledge on levels and patterns of PA in children is limited, due to the difficulty of precisely measuring this complex behaviour in normal daily living. Information on variables that significantly contributes to the variability in PA patterns is warranted as it may inform strategies for promoting physically active lifestyles in school-age youth. The overall purpose of the present studies was to increase the knowledge about the use of accelerometry when assessing PA in children, and examine sources of variability in objectively assessed PA behaviour in children. The study samples included 1954 nine- and 15-year-old children from four geographical locations in Europe (Norway, Denmark, Estonia and Portugal), and additionally 16 Swedish seven-year-old boys and girls. PA was assessed by the MTI accelerometer during free-living conditions, including both weekdays and weekend days. A part of the PA assessment was conducted using different time sampling intervals (epochs). Predictions of estimates of daily energy expenditure from accelerometer output were calculated using previously published equations. Potential correlates of PA behaviour were assessed by self-report. The main findings were; a) the epoch setting had a significant effect when interpreting time spent at higher intensities of PA in young children, b) predicted energy expenditure differed substantially between equations, c) between- and within-day differences in overall levels of PA, time spent at moderate-to-vigorous intensity physical activity and time spent sedentary differed between age, gender and geographical location, d) outdoor play and sports participation were differentially associated with objectively measured PA in 9- and 15-year-old children. It is concluded that the sporadic nature of children’s physical activity require very short epoch settings for detecting high intensity PA, and that different published equations for estimations of daily energy expenditure cannot be used interchangeably. The interpretations of average energy expenditure from available equations should be made with caution. Based on a large sample of children of different ages, weekend days and leisure time during weekdays seem appropriate targets when promoting PA in order to increase the proportion of children achieving current recommendations on health enhancing PA. Further, significant correlates of PA behaviour dependent on age group are presented, which should be considered when planning interventions for promoting PA in school-age youth.</p>

<p>Designing touch screen devices includes many variables off how to address design issues in the best possible way. The design includes what type of touch interaction method is to be used, how the interface is to be designed and in which context it will be used. The problematic issue that has to be dealt with is how the designer must put together all these parameters into one final product. This paper presents the case of re-designing a touch screen bedside monitor, a device used in hospitals to observe the vital signs of patients. The design solution presented deals with the issues of how the device was designed to suit the users and environment of a hospital. A contextual inquiry showed the many constraints and standards that had to be met and how they shaped the design solution. Earlier work shows the different methods for touch interaction, interface design and feedback that can be applied for touch screen devices. The resulting design is discussed in relation to the different ways of creating touch screen interfaces, and an example of a work method is presented in the end of the paper on how to design for contextual touch screen devises.</p>