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This thesis examines the development and testing of a novel 2 DOF (Degrees of Freedom) thermal actuator using Micro Electro Mechanical Systems (MEMS) technology. A out-of-plane displacement measurement technique based on optical focus adjustments is also implemented and tested. In-plane displacement measurement techniques are also compared. Existing MEMS actuator can either move in-plane or out-of-plane but no reported actuators were found to move in a user selectable combination of both domains. The novel actuator fabricated using the PolyMUMPs process is capable of displacements of 5 ?m out-of-plane and 1.5 ?m in-plane. A Finite Element Analysis (FEA) was performed as a proof of concept prior to physical construction. FEA was also used to characterize the actuator. Measuring out-of-plane displacements of MEMS devices is difficult to accomplish using only a standard microscope and camera setup. Methods have included tilting the chip so the vertical motion has a planar component. The most common commercial measurement technique uses interferomery but special expensive equipment is necessary. A method adapted from biological autofocus is proposed in which multiple images (100+) are taken at various focal planes. An algorithm is applied which extracts the most focused image. An out-of-plane displacement measurement can be extracted between two image sets. Results were compared to optical profiler measurements and the results had an average error of 0.47 ?m A comparison of planar displacement measurement methods, which included two variations of both edge detection and pattern matching along with measurements using the optical profiler, was accomplished. Consistent planar displacement results were collected for all techniques except for the simple edge detection.

Background: Nurses are responsible for the monitoring and assessment of blood pressure in the clinical setting. Increasing evidence has demonstrated that inaccurate measurement technique often leads to the misclassification of large numbers of individuals as hypertensive. The impact of untreated or poorly treated hypertension, due to misclassification of patients, is a major contributor to the overall burden of adult diseases in any population. Accurate measurement of blood pressure relies on knowledge and skill and is considered paramount in the management of cardiovascular risks. There seems to be limited information on the knowledge and skill of nurses in South Africa regarding the correct measurement of BP when using a sphygmomanometer and the auscultatory method. Given South Africa’s primary healthcare philosophy, and the significant role that nurses play in the prevention and treatment of hypertension, it is of importance to investigate nurses’ knowledge and skill of blood pressure measurement. Objectives: (i) to determine nurses’ skill and knowledge in measuring blood pressure using a sphygmomanometer and auscultation, and (ii) to determine if there is a correlation between nurses’ skill and knowledge of blood pressure measurement technique. Design and method: This study followed a quantitative, descriptive design with an observational checklist and survey method. In phase one, nurses’ skills of blood pressure measurement using a sphygmomanometer was determined by means of an observation checklist. In phase two, the researcher determined nurses’ knowledge of blood pressure measurement technique by using a standardised set of questions. Finally, the researcher investigated whether there was a correlation between nurses’ knowledge and their skill of blood pressure measurement technique in the mentioned setting. Results: Overall, the mean score for correctly completing the skills on the observational checklist was 87.7%. Nurses’ scored an average of 63.1% for knowledge of blood pressure measurement technique. The relationship between the assessment of skills and performance on the written questionnaire on knowledge was not significant (r=0,062, p=0,5). Conclusions: Although the average scores were 87.7% for skills and 63.1% for knowledge, this study identified deficts in both the knowledge and to a lesser degree, in the skill of nurses to understand and perform blood pressure measurement. Regular updates and carrying readily available documents on the standardized procedure for BP measurement techniques could support the training and correction of nurses’ knowledge and skill in the acute setting. Educational preparation that is more detailed may also greatly contribute to more understanding and knowledge of blood pressure for nurses involved in the diagnosis and treatment of cardiovascular risk. / MCur, North-West University, Potchefstroom Campus, 2014

Background: Nurses are responsible for the monitoring and assessment of blood pressure in the clinical setting. Increasing evidence has demonstrated that inaccurate measurement technique often leads to the misclassification of large numbers of individuals as hypertensive. The impact of untreated or poorly treated hypertension, due to misclassification of patients, is a major contributor to the overall burden of adult diseases in any population. Accurate measurement of blood pressure relies on knowledge and skill and is considered paramount in the management of cardiovascular risks. There seems to be limited information on the knowledge and skill of nurses in South Africa regarding the correct measurement of BP when using a sphygmomanometer and the auscultatory method. Given South Africa’s primary healthcare philosophy, and the significant role that nurses play in the prevention and treatment of hypertension, it is of importance to investigate nurses’ knowledge and skill of blood pressure measurement. Objectives: (i) to determine nurses’ skill and knowledge in measuring blood pressure using a sphygmomanometer and auscultation, and (ii) to determine if there is a correlation between nurses’ skill and knowledge of blood pressure measurement technique. Design and method: This study followed a quantitative, descriptive design with an observational checklist and survey method. In phase one, nurses’ skills of blood pressure measurement using a sphygmomanometer was determined by means of an observation checklist. In phase two, the researcher determined nurses’ knowledge of blood pressure measurement technique by using a standardised set of questions. Finally, the researcher investigated whether there was a correlation between nurses’ knowledge and their skill of blood pressure measurement technique in the mentioned setting. Results: Overall, the mean score for correctly completing the skills on the observational checklist was 87.7%. Nurses’ scored an average of 63.1% for knowledge of blood pressure measurement technique. The relationship between the assessment of skills and performance on the written questionnaire on knowledge was not significant (r=0,062, p=0,5). Conclusions: Although the average scores were 87.7% for skills and 63.1% for knowledge, this study identified deficts in both the knowledge and to a lesser degree, in the skill of nurses to understand and perform blood pressure measurement. Regular updates and carrying readily available documents on the standardized procedure for BP measurement techniques could support the training and correction of nurses’ knowledge and skill in the acute setting. Educational preparation that is more detailed may also greatly contribute to more understanding and knowledge of blood pressure for nurses involved in the diagnosis and treatment of cardiovascular risk. / MCur, North-West University, Potchefstroom Campus, 2014

MSc (Nursing), Faculty of Health Sciences, University of the Witwatersrand / The purpose of the study was to describe and compare the limits of agreement between invasive blood pressure (IBP) and non-invasive blood pressure (NIBP) readings obtained on patients in the adult critical care units (CCU) of a tertiary health care institution, to describe the factors that affect accuracy of both techniques, to describe the difference in terms of accuracy and sensitivity and the reasons given by the clinical practitioners for their choice of blood pressure measurement technique. A non-experimental descriptive comparative, prospective design was utilized in this two part study. The sample comprised of CCU patients (n = 80) in five adult critical care units over a 3-month period. Non-probability purposive sampling was utilized to obtain the desired sample in part one of the study. Data collection was via IBP and NIBP measurements obtained by the researcher and a record review of the patient’s critical care charts. Part two of the study comprised of clinical practitioners (n=50) and convenience sampling method was utilized. Descriptive and inferential statistics were used to analyse data. At the 95% confidence interval, the limits of agreements were found to be in range of ± 35 mmhg of IBP and NIBP systolic, ± 19.5 mmHg of IBP and NIBP diastolic and ±19.3 mmhg IBP and NIBP of mean arterial pressure. In practical terms this means that IBP and NIBP can not be used interchangeably in CCUs as the two methods did not consistently provide similar measurements because there was a high level of disagreement that included clinically important discrepancy of more than 10 mmhg which is the cut off acceptable reference in terms of discrepancy between the two BP techniques and add to the growing literature suggesting that IBP remains the gold standard technique for measuring the blood pressure in critical care setting. Factors such as Inotropic/ vasopressor support, sedation / analgesia, mechanical ventilation and severity of illness (APACHE II score) did not show significant influence on the discrepancy of the two BP techniques. In the second part of the study, more than 80 % of the sample of clinical practitioners acknowledged that the IBP technique remains the gold standard.

The ease of manufacturing using additive manufacturing (3D-Printing) reduces the overall production cost compared with the traditional manufacturing techniques. Because of the benefits of 3D printing technologies, it is proposed to be used in manufacturing of different products. But there are some flaws that are causing significant effect on 3D printed models which degrades the quality of the product. Hence in order to handle these defects, different measurement techniques are needed to quantify the defects that are seen on the surface of 3D-printed models. In our study there are two experimental setups. Experimental setup one was made to find out the proper coating timing to enable measurement using two good samples without defects in different colors blue and red with same material. Different 2D and 3D parameters were used for the surface measurements are collected and noted for further research. The Defective samples are measured using the state of the art equipment at Halmstad University. Experimental setup two was made to prepare the defective samples and measure the samples. The results obtained assisted to quantify the surface defects seen in the samples. This thesis studies some of the different methods that can be implemented to measure the surface defects on the 3D printed models. A little study on the various defects formed on the 3D printed models and what are the causes for the defects on the products were performed. The results suggest different method for the defects to be measured in both industrial and home or small scale office applications.

The measurement of Polycyclic Aromatic Hydrocarbons (PAHs) in flames is essential for the understanding of soot formation. In comparison to conventional aromatics-sampling techniques, a new technique was proposed that involves fewer manual operations and no hazardous extraction solvents. Apparatus and experimental procedures of the newly proposed adsorptive-sampling and desorptive-extraction technique for aromatic-hydrocarbon measurements were established in this study. The capabilities and limitations of this new technique were assessed in terms of limits of detection, sampling locations and data repeatability. The accuracy of this technique was also evaluated. Aromatic-hydrocarbon species concentrations were measured in laminar co-flow diffusion flames of ethylene (C2H4) and synthetic paraffinic kerosene (SPK). The results obtained from the ethylene flame were compared to its numerical simulation, with the goal of achieving agreement within an order of magnitude. The differences between simulated values and experimental measurements, along with the limitations of the technique, were used as an indication of the accuracy of the technique.

The measurement of Polycyclic Aromatic Hydrocarbons (PAHs) in flames is essential for the understanding of soot formation. In comparison to conventional aromatics-sampling techniques, a new technique was proposed that involves fewer manual operations and no hazardous extraction solvents. Apparatus and experimental procedures of the newly proposed adsorptive-sampling and desorptive-extraction technique for aromatic-hydrocarbon measurements were established in this study. The capabilities and limitations of this new technique were assessed in terms of limits of detection, sampling locations and data repeatability. The accuracy of this technique was also evaluated. Aromatic-hydrocarbon species concentrations were measured in laminar co-flow diffusion flames of ethylene (C2H4) and synthetic paraffinic kerosene (SPK). The results obtained from the ethylene flame were compared to its numerical simulation, with the goal of achieving agreement within an order of magnitude. The differences between simulated values and experimental measurements, along with the limitations of the technique, were used as an indication of the accuracy of the technique.

This thesis is composed of two distinct parts. The first part of this work addresses the problem of critical ignition behind a decaying shock wave in the context of cellular detonations. Low-pressure (4.1 kPa) shock tube experiments were performed in a thin rectangular channel using the highly-unstable mixture of CH4 + 2O2 and the weakly-unstable mixture of 2H2 + O2 + 7Ar, with Schlieren visualization of the flow field. The dynamics of the lead shock in a detonation cell was reconstructed from measurements of the lead shock position and curvature. The post-shock state and the expansion rate along the path of a Lagrangian particle crossing the lead shock at any given point in the cell cycle were evaluated with the shock jump and shock change equations. The chemical evolution behind the shock was then integrated using a detailed chemistry model. Quenching of the post-shock reaction zone was found within the first half of the detonation cell for both mixtures, with quenching occurring earlier in the highly unstable mixture. Simplified models derived from 1-step and 2-step chemistry models very accurately predict the quenching of the post-shock reactions and the evolution of the ignition delay through the cell. The second part describes the assembly and characterization of a fibre-optic probe hydrophone (FOPH) for the measurement of shock waves associated with blast-induced neuro-trauma. Compared to traditional polyvinylidene difluoride (PVDF) hydrophones, the assembled FOPH has a higher bandwidth and smaller active diameter, which are comparable to the characteristic time and thickness of shock waves associated with blast-induced neuro-trauma. However, the sensitivity of FOPHs are substantially lower than traditional hydrophones. We assemble a FOPH and provide detailed calculations and measurements of its sensitivity (0.66 mV/MPa) , noise floor, and spatial resolution. The 150 MHz bandwidth, limited by the photodetector, is sufficient for resolving shock waves with over-pressures of up to 174 kPa with 3 measurement points. Experimental measurements of the system noise gives a floor of 260 Pa/√Hz . A detailed noise analysis finds that the system is limited by photodetector noise (215 Pa/√Hz), which is 4x the fundamental shot noise limit, closely followed by a laser noise of 150 Pa/√Hz. We conclude that the system noise floor is insufficient for resolved measurements of the post-shock pressure in the range associated with blast-induced neuro-trauma. From our noise analysis, we quantify the sensitivity enhancement required for resolving this regime, and we conclude that sensitivity-enhancing fibre-coatings could provide a sufficient increase in sensitivity.

<p>In recent years, the drive for ever increasing energy efficiency has intensified. The main driving forces behind this development are the increased innovation and adoption of mobile battery powered devices, increasing energy costs, environmental concerns, and strive for denser systems.</p><p>This work is meant to serve as a foundation for exploration of energy conscious software. We present an overview of previous work and a background to energy concerns from a software perspective. In addition, we describe and test a few methods for decreasing energy consumption with emphasis on using software parallelism. The experiments are conducted using both a simulation environment and real hardware. Finally, a method for measuring energy consumption on a hardware platform is described.</p><p>We conclude that energy conscious software is very dependent on what hardware energy saving features, such as frequency scaling and power management, are available. If the software has a lot of unnecessary, or overcomplicated, work, the energy consumption can be lowered to some extent by optimizing the software and reducing the overhead. If the hardware provides software-controllable energy features, the energy consumption can be lowered dramatically.</p><p>For suitable workloads, using parallelism and multi-core technologies seem very promising for producing low power software. Realizing this potential requires a very flexible hardware platform. Most important is to have fine grained control over power management, and voltage and frequency scaling, preferably on a per core basis.</p>