Obstructive sleep apnea (OSA) is a prevalent disease. Often resources to provide care for OSA are inadequate, leading to long patient waiting times. Simpler validated methods of care are needed. In the first study in Chapter 2, the utility of a new high-sampling rate oximeter to diagnose OSA was explored. The home oximetry data collection was robust, with few failures and the data allowed the “rule in” or “rule out” of moderate-severe OSA with high degree of certainty. It is concluded that home oximetry could replace polysomnography (PSG) as a diagnostic test in a significant proportion of patients, thus allowing limited resources available for the care of those with OSA to be re-directed e.g. towards providing therapy. In Chapter 3, the diagnostic information from the oximeter was used to underpin a study designed to demonstrate that a nurse-led model of care could produce health outcomes in moderate-severe OSA not inferior to physician-led care. A randomised controlled multi-centre non-inferiority clinical trial was performed. 1,427 patients referred to 3 sleep medical centres with possible OSA were assessed. 195 patients were randomised to 2 models of care. Model A, a simplified model, involved home oximetry to diagnose moderate-severe OSA, auto-titrating constant positive airway pressure (APAP) to set a therapeutic constant positive airway pressure (CPAP), with all care supervised by an experienced nurse. Model B involved 2 laboratory PSG’s, to diagnose OSA then titrate CPAP, supervised by a sleep physician. The primary endpoint was change in Epworth Sleepiness Score (ESS) measured before and after 3 months of CPAP. A range of other outcome measures were collected. The change in ESS for nurse-led management (Model A) was not inferior to the physician-led service (Model B) since the lower limit of the two-sided 95% CI did not include -2, the margin of equivalence (difference 0.13, 95% CI -1.52 to -1.25). 11 patients in Model A and 10 in Model B were lost to follow up during the trial. There were no significant differences between Model A and Model B after 3 months of CPAP in any of the other outcome measures, including CPAP adherence at 3 months. It is concluded that a simplified nurse-led model of care can produce non-inferior results to physician-directed care in the management of moderate-severe OSA. In Chapter 4 the efficacy of CPAP in normalising or improving subjective and objective sleepiness, quality of life and selected neurocognitive measures was explored. It was shown that only a proportion of patients (60% on ESS, 35% on FOSQ) normalised their scores after 3 months of CPAP therapy. This is important information. As new health care delivery strategies evolve as a result of the data presented in Chapter 3 and elsewhere, it will be crucially important to train new health care professionals in the complexities of OSA management, such that they are aware that the symptoms of patients presenting for OSA investigations can have multiple aetiologies, and may not always resolve by simply applying CPAP. The data presented in this thesis add to the evidence base in treatment of moderate-severe OSA and will help further evolve health care delivery for this important disease.

This report was produced at the request of ABB Robotics and the work was conducted at their facilities in Västerås, Sweden. In the development of industrial robots the structures are slimmed to increase the accuracy and speed. When conducting finite element analysis on the robots the accuracy of the component modelling and definitions of the boundary conditions becomes more important. One such component is the ball bearing which consist of several parts and has a nonlinear behavior where the balls are in contact with the rings. The task given was to develop new methods to model roller bearings in Siemens finite element modelling software NX Nastran. Then conduct a strain measurement, to compare the methods to real experimental values. The goal with the report is to find one or more methods to model roller bearings, with accurate results, that can beused in their development work. The report was conducted by first doing a study on bearings and finite element modeling, and learning to use the software NX Nastran. Then the development of the methods were done by generating ideas for bearing models and testing them on simple structures. Nine methods was produced and a tenth, the method used to model bearings today, was used as a reference. The methods was used to build bearing models in a finite element model of a six axis robot wrist. Simulations were done on the models with different load cases and the results were compared to a strain measurement of the wrists real counterpart. Only six of the models were analyzed in the result, since four of the models returned results that were deemed unusable. When compiling the result data no model was found to accurately recreate the stresses in every load case. Three methods, that allow deformation, performed similarly. One of them is suggested to be used as modelling method in the future. Worst of the methods, according to the results compiled, was found to be the method used today. It fails to describe local stresses around the bearing. For continued work it is suggested that linear contact elements is studied further. Four out of five models constructed with linear contact elements failed to return satisfactory results.

Interest in the delta operator as a tool in the development of robust approaches to modelling and control has been revived in the last decade, principally following the work of Goodwin (1985). The use of this discrete differential operator provides improved numerical properties particularly when modelling or implementing control at high sampling frequencies or under finite wordlength restraints. The delta operator also provides for the alliance of continuous time designs and discrete time application, linking traditional control theory with modern implementation through digital computing. In this thesis, a delta operator Simplified Refined Instrumental Variable (SRIV) approach to model estimation is employed, together with model order identification tools, to provide delta operator models for use in control and forecasting. The True Digital Control (TDC) design theory is adopted to develop a delta operator Proportional-Integral-Plus (PIP) controller. The construction of realisable control filters enables implementation of the PIP controller, the structure of which can prove operationally significant. A number of refinements to the standard PIP controller are developed and applications are presented for engineering and environmental examples. The development of a recursive delta operator Kalman filter is presented and incorporated within a forecasting framework. The resulting algorithm is applied to historical data to generate real time stochastic forecasts of river flows from an effective rainfall-flow model.

The joint may be considered a weak point along the pipe and can have a major impact on pipe performance. However, little research has been conducted in regard to joint design. To improve current structural design criteria, this thesis presents the findings and conclusions of experimental and computational studies of the effects of longitudinal bending on joints in rigid (reinforced concrete) and flexible (corrugated steel and thermoplastic) pipes. Solutions for expected shear force, longitudinal bending moment and rotation across the joint for rigid and flexible pipes are formulated for use in structural design of pipe joints. Exact algebraic solutions for rigid pipes are derived using the beam-on-elastic-spring approximation. The formulations for flexible pipes are developed assuming that the two pipes are very long, and that the response is not affected by either the location or characteristics of those other joints. The flexible pipe design equations are developed using various closed form solutions for beams on elastic foundations developed by Hetényi (1948). Parametric studies are then presented where the key factors controlling the behaviour are examined, and the comparisons to recent experimental measurements show that the joint rotation calculated using the equations and a value of soil stiffness proposed for use in design are generally reasonable and conservative compared with the laboratory tests. To measure the capacity of the joint to accommodate the demands, a pipe joint testing frame has been designed to facilitate joint characterization experiments. Shear tests and articulation (rotation) tests have been conducted using this testing frame to examine the shear force capacity, longitudinal bending moment capacity of moment-transfer joints, and rotational characteristics of joints. The shear test results show that the joints of PVC pipe and corrugated steel pipe have similar shear stiffness while the reinforced concrete pipe joint is significantly stiffer. The results of the articulation testing indicate that the rotational capacities of the three joint systems are similar in general. Design of rotational capacity of these joints is likely dominated by considerations of assembly in the field, rather than the rotational capacity that is needed once the pipes are installed. / Thesis (Master, Civil Engineering) -- Queen's University, 2013-01-31 15:33:41.058

Abstract Researchers differ in their opinions regarding the use of authentic or simplified novels. This paper attempts to clarify some of the different standpoints taken by the advocates for both the authentic and the simplified alternative. However, the aim of the essay is to show the benefits of using authentic literature such as Walkabout by James V. Marshall and to contextualize this with results from a small-scale study and with the help of different critical material.

<p><strong>Abstract</strong></p><p>Researchers differ in their opinions regarding the use of authentic or simplified novels. This paper attempts to clarify some of the different standpoints taken by the advocates for both the authentic and the simplified alternative. However, the aim of the essay is to show the benefits of using authentic literature such as <em>Walkabout</em> by James V. Marshall and to contextualize this with results from a small-scale study and with the help of different critical material.</p><p><strong> </strong></p><p> </p><p> </p><p> </p><p> </p><p> </p><p> </p><p> </p><p> </p><p> </p>

ASCE Manual No.74 (2010) and the Electric Power Research Institute (EPRI, 1997) provide methods for calculating the unbalanced longitudinal loads on a transmission line due to a wire breakage. The calculated loads from the two are different. In this study, a simplified transmission line was created using the equivalent geometric properties of a detailed transmission line. Non-linear dynamic analyses of the 10-span simplified transmission line due to cable breakage events in the first span were studied using ANSYS. The analyzed longitudinal loads were found to vary for different S/S, S/I, and K’s as specified in the EPRI. An equation for the longitudinal load factor as a function of the S/S, S/I, and K was then formulated based on the analysis. The longitudinal load factors from the formulated equation were found to be almost double those given by the ASCE manual and comparable to those calculated using the EPRI formulation.

ASCE Manual No.74 (2010) and the Electric Power Research Institute (EPRI, 1997) provide methods for calculating the unbalanced longitudinal loads on a transmission line due to a wire breakage. The calculated loads from the two are different. In this study, a simplified transmission line was created using the equivalent geometric properties of a detailed transmission line. Non-linear dynamic analyses of the 10-span simplified transmission line due to cable breakage events in the first span were studied using ANSYS. The analyzed longitudinal loads were found to vary for different S/S, S/I, and K’s as specified in the EPRI. An equation for the longitudinal load factor as a function of the S/S, S/I, and K was then formulated based on the analysis. The longitudinal load factors from the formulated equation were found to be almost double those given by the ASCE manual and comparable to those calculated using the EPRI formulation.

To investigate the benefit induced by adding a small amount of bonded reinforcing steel into a fully unbonded prestressed concrete beam, two well-founded and straightforward approaches for predicting tendon stress are proposed. The primary approach utilizes a flexural analysis to calculate member deformation. The supplementary approach employs a truss model to consider the additional member deformation due to shear force. Both approaches use a simplified iterative method. With these two approaches, a systematic parametric study is conducted to investigate the effects of various factors. The results indicate that adding little bonded reinforcement does significantly increase the stress increment in unbonded tendons at ultimate state for one-point loading as expected. Moreover, a lower span-to-depth ratio, the use of high-strength concrete, and a smaller mechanical reinforcement ratio also raise the stress increment.

To investigate the benefit induced by adding a small amount of bonded reinforcing steel into a fully unbonded prestressed concrete beam, two well-founded and straightforward approaches for predicting tendon stress are proposed. The primary approach utilizes a flexural analysis to calculate member deformation. The supplementary approach employs a truss model to consider the additional member deformation due to shear force. Both approaches use a simplified iterative method. With these two approaches, a systematic parametric study is conducted to investigate the effects of various factors. The results indicate that adding little bonded reinforcement does significantly increase the stress increment in unbonded tendons at ultimate state for one-point loading as expected. Moreover, a lower span-to-depth ratio, the use of high-strength concrete, and a smaller mechanical reinforcement ratio also raise the stress increment.