Obstructive sleep apnoea (OSA) is a common disorder involving repeated cessations of breathing due to airway collapse, causing disruption of sleep cycles. The condition is under-diagnosed and the side effects are many and varied. Currently, the ‘gold standard’ diagnostic tool for OSA is a polysomnogram (PSG) which is carried out overnight in a hospital using multiple sensors. A PSG is expensive to set-up, run and analyse, and some subjects experience different sleep patterns due to the artificial conditions of the sleep laboratory. The aim of this thesis was to find a parsimonious and easy-to-collect set of signals (from the superset of signals recorded in sleep clinics) and other related information (such as demographics), and a set of automated methods that reliably determine which subjects are suitable for standard treatments, i.e. classify subjects requiring treatment (moderate OSA, severe OSA) from those not requiring treatment (normal, snorer, mild OSA), using a smartphone. Data were collected from 1354 subjects in the home using the Grey Flash polysomnographic recording device (Stowood Scientific Instruments, Oxford, UK). Analysis of the audio signal was initially performed using standard speech processing methods, where individual events were annotated and classified. The results achieved (accuracy (Ac) = 69.6%) using this approach were lower than those required for clinical acceptance. In all subsequent work in the thesis, subjects were classified from entire recordings rather than events. Multiscale entropy (MSE) was used to identify non-linear correlations in the audio data and quantify the irregularity of the data over many time scales. The inter-snore interval (ISI) was developed, motivated by clinical intuition. MSE and ISI were then applied to both actigraphy and photoplethysomgraphy (PPG) data, and different combinations of features were analysed. The features which displayed the highest predictive accuracy were derived from the PPG signal (Ac = 89.2%). This work demonstrated that, although audio- and actigraphy-based OSA screening is possible, to achieve clinically acceptable performance PPG remains an important key factor in diagnosis.

The primary object of this investigation is to design a system, including equipment and procedures, that can be used to evaluate the noise characteristics of photoconductive cells. The data once collected must be in a comprehensive and useful form. The secondary object is to use this system to evaluate a large number of cells of various types and to compare their noise profiles in a manner such that definite conclusions can be drawn concerning the absolute noise levels and profiles generated by the various cell types and the relations that may exist between the cells' noise output and the way they were fabricated.

Thesis (M.App.Sc.) - Carleton University, 2006. / Includes bibliographical references (p. 84-87). Also available in electronic format on the Internet.

<p> The United States is competing on a global level for jobs in the STEM fields but retention and graduation rates in the engineering disciplines are lower than desired. African American males make up 5 % of the population of American colleges and universities (Strayhorn, 2010) and many of those pursuing an engineering degree often are not academically prepared for a career in engineering. There are African American males who have successfully persisted in engineering; however, limited research is provided about the success of these African American males and their experiences in engineering programs. The purpose of this study was to understand factors that impact successful persistence of African American male engineering majors at a predominantly White institution. Critical Race Theory was used as a framework to gain a broader scope of the underlying themes interwoven into the fabric of American society and a better understanding of the perceptions about African American male engineering majors. A qualitative case study was conducted to understand real-world phenomena through the experiences of successful African American male engineering majors. Using constant comparative analysis technique, two major themes were identified: Overcoming challenges and social identity. Early academic experiences, developing a positive identity, and a connection to others experiencing similar challenges were found to contribute to successful persistence.</p><p>

<p> Within the confines of this study, the researcher investigated Project Lead the Way (PLTW) Engineering curriculum goals within Missouri high schools. The study measured Missouri PLTW teachers&rsquo; perceptions of various elements of the curriculum as well as state and national PLTW End of Course student assessment data to determine if a relationship existed between teachers&rsquo; perceptions of curriculum implementation and student performance, as measured through Missouri End of Course exams in various secondary engineering classes. In addition, the researcher conducted voluntary interviews with teachers, state administrators, and national representatives of PLTW to inquire about experiences with the PLTW Engineering curriculum. </p><p> Qualitatively, Missouri PLTW Engineering teachers expressed varied levels of satisfaction through a survey generated by the researcher, based upon national curriculum goals established by PLTW. Within the study, teachers&rsquo; perceptions reported students&rsquo; abilities to identify, formulate, and solve engineering problems were greater than students&rsquo; abilities to design and conduct experiments, as well as to demonstrate knowledge of and responsibility for engineering issues, including ethical and professional responsibilities. The researcher attributed this perception to students&rsquo; lack of professional experience and to PLTW curriculum not providing enough opportunities for students to gain real-world relevant experience using the content and strategies learned during instructional class time. </p><p> The intention of this study was to provide a framework to review and evaluate curriculum goals established by PLTW, Inc. Originally, the researcher looked at national goals for the program to determine the outcomes of PLTW&rsquo;s educational programming. However, much of the data was post-secondary related and the researcher wanted to maintain the quantitative nature of the study. Nonetheless, research could expand upon the framework to study any state in the nation through either a mixed-methods approach or the use of a quantitative study approach. The researcher recommends further research be conducted either by PLTW, Inc., through state PLTW affiliates or by other individuals to determine future outcomes of educational curriculum offered by PLTW. This could include engineering, biomedical science, computer science, middle school curriculum offered through Gateway to Technology (GTT), or through elementary curriculum offered through Launch.</p><p>

The main objective of this investigation is to study experimentally the behavior of rectangular reinforced concrete frames subject to a combination of low column loads, beam loads, and lateral load. The analytical tool used in this investigation is a computer program which is a generalized computational method for non linear force deformation relationship and secondary forces due to displacement of the joints during loading. In the experimental portion of this investigation, two rectangular frames, one design by the Ultimate Strength Design method and the other by a Limit Design method were prepared and tested to failure with short time loading. Physical tests indicate that frames under the action of low gravity loads and lateral load became unstable after the formation of two hinges in the beams.

In this paper the effects of inertia are explored for the case of a thermal excitation applied on the surface of an infinitely long, solid circular cylinder. The linear uncoupled field equations for a homogeneous, isotropic, thermoelastic medium are used to derive the desired field equations of stress and displacement. The solution procedure included, first, the determination of the thermal boundary value problem from the energy equation which is identically satisfied for the uncoupled condition. Secondly, substitution of the strain-displacement relationships and the previously obtained thermal relation into the equilibrium equation containing inertial effects. The equilibrium equation is the only nonidentically satisfied equation. Thirdly, a solution of this equation is then found in the S-domain by Laplace transformation. Finally, the desired displacement equation is transformed into the time-domain as a function of temperature, time and radius of the cylinder by using inverse Laplace transforms and the calculus of residues.

No description available.

No description available.

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