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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
101

DEVELOPMENT OF A LASER LIFETIME PRESSURE-SENSITIVE PAINT METHOD FOR TURBINE ANALYSIS

Papa Aye Nyansafo Aye-Addo (11811563) 19 December 2021 (has links)
<p>To increase overall aircraft engine efficiency, the diameter of the high-pressure turbine is reduced, leading to low aspect ratio airfoils. Secondary flow dominates in these low aspect ratio turbines, and the small airfoil geometry inhibits flush-mounted, full-spatial dynamic pressure measurements with pressure transducers. Airfoil surface pressure measurements are vital to understanding the inherently unsteady flow phenomena in turbines. Additionally, aerodynamic performance data derived from high-resolution surface pressure measurements provide invaluable data for validating computational fluid dynamics codes used for prediction. Non-intrusive measurement techniques such as fast-responding Pressure Sensitive Paint (PSP) offer a potential solution of a full-field optical measurement of surface pressure fluctuation, with each camera pixel representing a sensor. The porous binder improves the dynamic response of PSP, making it suitable for unsteady flow environments such as turbomachinery applications. In this view, the overall objective of the current doctoral research is to develop a lifetime PSP method using laser-based excitation for surface pressure measurement on a new class of high-pressure turbines. </p> <p>The overall research goal was subdivided into three main strategies. (1) A pulse lifetime calibration procedure of a porous polymer/ceramic binder PSP was developed in a pressure-controlled chamber to assess the correlation between pressure and time-resolved luminescent lifetime, pressure sensitivity, and signal-to-noise ratio. (2) The lifetime technique was implemented for surface pressure measurements in a linear test section to measure high spatial pressure gradients and resolve unsteady flow features. A data reduction routine and an optimal binning bundle of pixels were proposed for calibration analysis to reduce the overall pressure uncertainty. Uncertainty quantification and sensitivity analysis were also completed to determine the parameters with a substantial effect on the pressure uncertainty. (3) The pulse lifetime method was demonstrated on a high-pressure turbine vane suction surface at engine representative conditions. The surface pressure data were corroborated with static pressure tappings and computational simulations. This research effort provided new insights into time-resolved luminescent lifetime PSP techniques. Steady and unsteady flow features from surface pressure measurements were identified using a precise calibration method. The lifetime pulse method was effective in a high-pressure turbine flow field, paving the way for back-to-back PSP experiments with different turbine geometries. </p>
102

Šíření tlakových pulsací v pružných plastových hadicích / Pressure pulsation propagation in elastic hoses

Čapoš, Eduard January 2020 (has links)
This thesis deals with propagation of pressure and flow pulsations, which are strongly affected by the tube flexibility. There are two mathematic models introduced, which are derived from basic physical relations. First model assumes velocity only in the axis direction. Second one assumes also non-zero radial velocity. Kelvin-Voigt model for viscoelasticity was used. Furthermore, experimental measurement was designed and evaluated. Measured data was used to calculate material properties. In addition, dynamic transfer was determined.
103

Untersuchung des Einflusses orthopädischer Beschlagsmodifikationen und Bodenbeschaffenheiten auf die Druckbelastung des Hufes und den Fußungsablauf sowie die Ausrichtung der distalen Zehenknochen des Pferdes

Geiger, Michael 19 November 2019 (has links)
Ziel der Untersuchung war eine umfassende und vergleichbare Datengrundlage über den Einfluss verschiedener hauptsächlich orthopädischer Beschlagsmodifikationen auf die Ausrichtung der Zehenknochen, Druckverteilungsmuster und die individuelle Fußung unter Berücksichtigung unterschiedlicher klinisch relevanter Bodeneigenschaften zu generieren und mit Standardbeschlägen, sowie dem Barhuf zu vergleichen.:1 Einleitung 1 2 Literaturübersicht 3 2.1 Anatomie der distalen Gliedmaße des Pferdes 3 2.1.1 Knochen und Gelenke 3 2.1.2 Sehnen und Bänder 6 2.1.3 Der Huf und seine Segmente 10 2.1.3.1 Definition des Hufs 10 2.1.3.2 Der Hufbeinträger 10 2.1.3.3 Segmente des Hufs 11 2.2 Biomechanische Grundlagen 13 2.2.1 Allgemeine Betrachtungsweisen der Biomechanik 13 2.2.2 Die Statik der distalen Gliedmaße des Pferdes 15 2.2.3 Kinetische Betrachtung der distalen Gliedmaße des Pferdes 17 2.3 Analysemethoden biomechanischer Prozesse der distalen Gliedmaße des Pferdes 19 2.3.1 Statische Analysemethoden 20 2.3.1.1 Röntgen 20 2.3.2 Kinetische Analysemethoden 22 2.3.2.1 Druckmessung 22 2.4 Lahmheit und deren Ursachen im Bereich der distalen Gliedmaße 23 2.4.1 Definition des Begriffes Lahmheit und deren Erkennung 24 2.4.2 Risikofaktoren für die Entstehung von Lahmheit 25 2.5 Orthopädischer Beschlag 27 2.5.1 Erkrankungen der distalen Gliedmaße mit Beschlagsindikation 27 2.5.2 Beschlagsmodifikationen 28 2.5.2.1 Beschlagsmodifikationen der dorsopalmaren Ebene 29 2.5.2.2 Beschlagsmodifikationen der mediolateralen Ebene 34 2.5.3 Der Einfluss unterschiedlicher Bodeneigenschaften auf die Wirkung orthopädischer Beschlagsmodifikationen 36 3 Wissenschaftliche Originalarbeiten 38 3.1 Modifying the Surface of Horseshoes: Effects of Eggbar, Heartbar, Open Toe, and Wide Toe Shoes on the Phalangeal Alignment, Pressure Distribution, and the Footing Pattern 38 3.2 Modifying the Height of Horseshoes: Effects of Wedge Shoes, Studs, and Rocker Shoes on the Phalangeal Alignment, Pressure Distribution, and Hoof-Ground Contact During Motion 51 3.3 Modifying Horseshoes in the Mediolateral Plane: Effects of Side Wedge, Wide Branch, and Unilateral Roller Shoes on the Phalangeal Alignment, Pressure Forces, and the Footing Pattern 63 4 Diskussion 73 4.1 Material und Methoden 73 4.1.1 Röntgenuntersuchung 73 4.1.2 Druckmessung 75 4.1.3 Kombination von Röntgenuntersuchungen und Druckmessungen zur Beurteilung biomechanischer Fragestellungen 78 4.2 Die Veränderungen der Zehenknochenausrichtung nach Applikation von orthopädischen Beschlagsmodifikationen 79 4.3 Die Veränderungen des Druckverteilungsmusters unter Hufeisen und Huf nach Applikation von orthopädischen Beschlagsmodifikationen 81 4.4 Der Effekt von orthopädischen Beschlagsmodifikationen auf die individuelle Fußung 84 4.5 Schlussfolgerungen und Ausblick86 5 Zusammenfassung 88 6 Summary 90 7 Literaturverzeichnis 93 / Aim of this study was to establish comprehensive and comparable data groundwork on the influence of a variety of modified horseshoes on the alignment of the bone of the equine distal limb, pressure distribution and individual footing patterns, while considering different practically relevant flooring materials, in comparison to data acquired with standard horseshoes and barefoot examinations.:1 Einleitung 1 2 Literaturübersicht 3 2.1 Anatomie der distalen Gliedmaße des Pferdes 3 2.1.1 Knochen und Gelenke 3 2.1.2 Sehnen und Bänder 6 2.1.3 Der Huf und seine Segmente 10 2.1.3.1 Definition des Hufs 10 2.1.3.2 Der Hufbeinträger 10 2.1.3.3 Segmente des Hufs 11 2.2 Biomechanische Grundlagen 13 2.2.1 Allgemeine Betrachtungsweisen der Biomechanik 13 2.2.2 Die Statik der distalen Gliedmaße des Pferdes 15 2.2.3 Kinetische Betrachtung der distalen Gliedmaße des Pferdes 17 2.3 Analysemethoden biomechanischer Prozesse der distalen Gliedmaße des Pferdes 19 2.3.1 Statische Analysemethoden 20 2.3.1.1 Röntgen 20 2.3.2 Kinetische Analysemethoden 22 2.3.2.1 Druckmessung 22 2.4 Lahmheit und deren Ursachen im Bereich der distalen Gliedmaße 23 2.4.1 Definition des Begriffes Lahmheit und deren Erkennung 24 2.4.2 Risikofaktoren für die Entstehung von Lahmheit 25 2.5 Orthopädischer Beschlag 27 2.5.1 Erkrankungen der distalen Gliedmaße mit Beschlagsindikation 27 2.5.2 Beschlagsmodifikationen 28 2.5.2.1 Beschlagsmodifikationen der dorsopalmaren Ebene 29 2.5.2.2 Beschlagsmodifikationen der mediolateralen Ebene 34 2.5.3 Der Einfluss unterschiedlicher Bodeneigenschaften auf die Wirkung orthopädischer Beschlagsmodifikationen 36 3 Wissenschaftliche Originalarbeiten 38 3.1 Modifying the Surface of Horseshoes: Effects of Eggbar, Heartbar, Open Toe, and Wide Toe Shoes on the Phalangeal Alignment, Pressure Distribution, and the Footing Pattern 38 3.2 Modifying the Height of Horseshoes: Effects of Wedge Shoes, Studs, and Rocker Shoes on the Phalangeal Alignment, Pressure Distribution, and Hoof-Ground Contact During Motion 51 3.3 Modifying Horseshoes in the Mediolateral Plane: Effects of Side Wedge, Wide Branch, and Unilateral Roller Shoes on the Phalangeal Alignment, Pressure Forces, and the Footing Pattern 63 4 Diskussion 73 4.1 Material und Methoden 73 4.1.1 Röntgenuntersuchung 73 4.1.2 Druckmessung 75 4.1.3 Kombination von Röntgenuntersuchungen und Druckmessungen zur Beurteilung biomechanischer Fragestellungen 78 4.2 Die Veränderungen der Zehenknochenausrichtung nach Applikation von orthopädischen Beschlagsmodifikationen 79 4.3 Die Veränderungen des Druckverteilungsmusters unter Hufeisen und Huf nach Applikation von orthopädischen Beschlagsmodifikationen 81 4.4 Der Effekt von orthopädischen Beschlagsmodifikationen auf die individuelle Fußung 84 4.5 Schlussfolgerungen und Ausblick86 5 Zusammenfassung 88 6 Summary 90 7 Literaturverzeichnis 93
104

Evaluating the Pulse Sensor as a Low-Cost and Portable Measurement of Blood Pulse Waveform

Smithers, Breana Gray 05 1900 (has links)
This study was aimed at determining whether the digital volume pulse waveform using the Pulse Sensor can be used to extract features related to arterial compliance. The Pulse Sensor, a low-cost photoplethysmograph, measures green light reflection in the finger and generates output, which is indicative of blood flow and can be read by the low-cost Arduino UNO™. The Pulse Sensor code was modified to increase the sampling frequency and to capture the data in a file, which is subsequently used for waveform analysis using programs written in the R system. Waveforms were obtained using the Pulse Sensor during two 30-s periods of seated rest, in each of 44 participants, who were between the ages of 20 and 80 years. For each cardiac cycle, the first four derivatives of the waveform were calculated and low-pass filtered by convolution before every differentiation step. The program was written to extract 19 features from the pulse waveform and its derivatives. These features were selected from those that have been reported to relate to the physiopathology of hemodynamics. Results indicate that subtle features of the pulse waveform can be calculated from the fourth derivative. Feature misidentification occurred in cases of saturation or low voltage and resulted in outliers; therefore, trimmed means of the features were calculated by automatically discarding the outliers. There was a high efficiency of extraction for most features. Significant relationships were found between several of the features and age, and systolic, diastolic, and mean arterial blood pressure, suggesting that these features might be employed to predict arterial compliance. Further improvements in experimental design could lead to a more detailed evaluation of the Pulse Sensor with respect to its capability to predict factors related to arterial compliance.
105

Assessment of catheter-manometer systems used for invasive blood pressure measurement

Heimann, P A January 1989 (has links)
Direct measurement of blood pressure using a fluid-filled catheter and an electromechanical transducer is widely accepted in clinical practice. However, errors associated with the measurement are often not appreciated and these catheter-manometer systems are frequently unable to accurately reproduce applied pressures. To assess the accuracy of catheter-manometer systems used for invasive arterial blood pressure measurements, in vitro and in vivo evaluations were performed. The frequency response (described in terms of damped natural frequency and damping factor) for a variety of cannulae, pressure tubing and stopcocks (and combinations thereof) and their dependence on various parameters (catheter length, lumen diameter, fluid temperature and catheter material) were measured using an hydraulic pressure generator. The design and construction details of the pressure generator are presented. It was found that the damped natural frequency of the catheter-manometer system is directly proportional to lumen diameter of the pressure tubing/catheter. Furthermore, damping factor is inversely related to the damped natural frequency and stiffer catheter material (for identical radius ratios) results in higher damped natural frequency. Catheter length is inversely related to damped natural frequency and the resonant frequency decreases for an increase in fluid operating temperature. It was established that all catheter-manometer systems tested were under-damped (0.15 < β < 0.37) and that the damped natural frequency ranged from 10.5 Hz for 1500 mm to 27.0 Hz for pressure tubing of 300 mm in length. Furthermore, catheter-manometer systems which had pressure tubing in excess of 300 mm in length did not comply with the bandwidth requirements for accurate dynamic blood pressure measurement. For the in vivo assessment of the catheter-manometer system, the blood pressure waveform was analysed in the time and frequency domains. It was established that in 60 percent of the cases, the systolic pressure peak was higher when measured by a narrow bandwidth catheter-manometer system compared to that measured by a wide bandwidth system. Furthermore, values of dp/dt maximum were lower for wide bandwidth catheter-manometer systems than those measured by narrow bandwidth systems for heart rates above 90 beats per minute. In the frequency domain analysis, artifact was sometimes found to occur at frequencies higher than the bandwidth of the catheter-manometer system. This high frequency artifact was found to distort the blood pressure waveform and resulted in false high dp/dt and peak systolic pressures.
106

Inter-arm difference in systolic blood pressure in different ethnic groups and relationship to the 'white coat effect'�: a cross sectional study

Schwartz, C.L., Clark, C.E., Koshiaris, C., Gill, P.S., Greenfield, S.M., Haque, M.S., Heer, G., Johal, A., Kaur, R., Mant, J., Martin, U., Mohammed, Mohammed A., Wood, S., McManus, R.J. 05 May 2017 (has links)
Yes / Inter-arm differences (IAD) ≥10mmHg in systolic blood pressure (BP) are associated with greater incidence of cardiovascular disease. The effect of ethnicity and the white coat effect (WCE) on significant systolic inter-arm differences (ssIADs) are not well understood. Methods: Differences in BP by ethnicity for different methods of BP measurement were examined in 770 people (300 White British, 241 South Asian, 229 African-Caribbean). Repeated clinic measurements were obtained simultaneously in the right and left arm using two BP-Tru monitors and comparisons made between the first reading, mean of second and third and mean of second to sixth readings for patients with, and without known hypertension. All patients had ambulatory monitoring (ABPM). WCE was defined as systolic Clinic BP ≥10mmHg higher than daytime ABPM. Results: No significant differences were seen in the prevalence of ssIAD between ethnicities whichever combinations of BP measurement were used and regardless of hypertensive status. ssIADs fell between the 1st measurement (161, 22%), 2nd/3rd (113, 16%) and 2nd-6th (78, 11%) (1st vs 2nd/3rd and 2nd-6th, p<0.001). Hypertensives with a WCE were more likely to have ssIADs on 1st, (OR 1.73 (95% CI 1.04-2.86), 2nd/3rd, (OR 3.05 (1.68-5.53) and 2nd-6th measurements, (OR 2.58 (1.22-5.44). Non-hypertensive participants with a WCE were more likely to have a ssIAD on their first measurement (OR 3.82 (1.77 -8.25) only. Conclusion: ssIAD prevalence does not vary with ethnicity regardless of hypertensive status but is affected by the number of readings, suggesting the influence of WCE. Multiple readings should be used to confirm ssIADs. / This report presents independent research funded by the National Institute for Health Research (NIHR).
107

Desenvolvimento de técnica de medição e obtenção de dados experimentais envolvidos no ciclo de trabalho dos compressores herméticos alternativos / Development of techniques to measure and extract experimental data of hermetic compressor work cycle

Real, Marcelo Alexandre 20 December 2005 (has links)
Essa dissertação desenvolve e faz uso de uma técnica de medição com objetivo de obter dados experimentais envolvidos no ciclo de trabalho dos compressores herméticos alternativos, largamente utilizados nos sistemas de refrigeração. O trabalho mostra o comportamento das válvulas de admissão e descarga durante o funcionamento do compressor, as pressões no cilindro, na sucção, na descarga e também a variação de rotação do eixo durante um ciclo de compressão completo. Todas as características mensuradas estão referenciadas à posição angular do eixo do compressor, o que permitiu monitorar todos os eventos em função do seu deslocamento angular. Para o desenvolvimento desse trabalho foi necessário planejar um sistema de medição robusto, não vulnerável aos fatores ambientais, presentes dentro da carcaça do compressor. A limitação do espaço físico foi um fator de grande importância na escolha dos sensores, assim como a velocidade de resposta dos instrumentos, pois um ciclo de compressão tem período menor que 0,020 segundos. A coleta dos dados e a análise dos sinais foram realizadas com o auxilio de hardware apropriado e software especialmente desenvolvido. / In this dissertation it is developed and applied measurement methods to obtain experimental data of a hermetic compressor work cycle, widely used in the refrigeration systems. This work shows the suction and discharge valve behaviors, the pressure in the cylinder, as well as in the discharge and suction chambers, and also crankshaft rotation variation during a complete compression cycle. All the measurements are reference to crankshaft angular position of compressor which allows to verify the events as a function of the crankshaft angular displacement. For the development of this work it was necessary to plan a reliability measure system, not affected by environmental factors inside the housing of compressor. The inner space limitation was an important feature for choosing the sensors as well as their time response, since the period compression cycle is less than 0.020 seconds. The data acquisition and signal analysis were done with appropriate hardware and it was developed a specific software.
108

Uso da medida da pressão em casa como estratégia de controle da pressão arterial de um grupo de hipertensos  de Peruíbe - SP / Use of home blood pressure measurement as a control strategy in a group of hypertensive patients from Peruibe SP

Silva, Giane Christina Alves da 29 November 2010 (has links)
Introdução: a falta de controle dos hipertensos tem sido um desafio para os profissionais de saúde, e a medida da pressão em casa pode ser um recurso para aumentar o controle da pressão arterial. Realizou-se um estudo para avaliar o efeito do uso da medida da pressão em casa no controle da pressão arterial em um grupo de hipertensos. Objetivos: avaliar o efeito do uso da medida da pressão em casa no controle da pressão arterial em grupo de hipertensos do Município de Peruibe SP. Objetivos específicos: 1- comparar o controle da pressão arterial dos hipertensos submetidos à medida da pressão em casa; 2- avaliar o controle da pressão arterial dos hipertensos, considerando a monitorização residencial da pressão (MRPA) como método de avaliação pré e pós-medida da pressão em casa; 3- identificar associações entre o controle da pressão arterial com as variáveis biopsicossociais, hábitos de vida, comportamentos e atitudes frente à doença e tratamento; 4- avaliar adesão ao tratamento utilizando o questionário Fatores Dificultadores da Adesão (FDA) e o teste de Morisky e Green. Casuística e Método: pesquisa de campo, longitudinal, pareada com abordagem quantitativa. Os participantes realizaram a medida da pressão arterial em consultório no início e final do estudo. A medida da pressão em casa foi realizada com aparelho automático, validado durante 8 semanas às segundas, quartas e sextas-feiras pela manhã (entre 6 e 10h) e à noite (entre18 e 22h). A utilização da monitorização residencial da pressão arterial (MRPA), no início e no final do estudo, teve o propósito de avaliar a eficácia do uso da medida da pressão em casa, como estratégia de aumento do controle da pressão arterial, foi realizada nas semanas 1 e 10 durante 7 dias com o mesmo aparelho, três medidas pela manhã (entre 6 e 10h) e 3três medidas à noite (entre18 e 22h) na posição sentada com 10 minutos de repouso e com manguito adequado. Os valores de p<0,05 foram considerados significantes. Exames de glicemia em jejum, colesterol total e frações, triglicérides, ureia e creatinina foram coletados. Avaliou-se adesão com o questionário fatores dificultadores da adesão e o teste de Morisky e Green, presença de transtornos mentais comuns com o Self Report Questionnaire (SRQ 20), risco de danos à saúde relacionado ao uso de bebidas alcoólicas com o questionário Alcohol Use Disorders Identification (AUDIT) e suporte social com a Escala de Apoio Social. Resultados: foram estudados 71 hipertensos com idade de 63,3±11 anos; 53,5% homens; 77,5% brancos; 77,1% ensino fundamental/médio; 53,5% aposentados; 52,1% renda 2 salários mínimos e não tabagista;19,7% sedentários; índice de massa corporal 30,8±5,8 kg/m2; 35,2% etilista, 43,7% aderentes ao teste de Morisky e Green e 32,4% positivos para o SRQ-20. Destaca-se que em 19 das 25 perguntas do formulário fatores dificultadores da adesão, foi obtido percentual acima de 90% no apontamento dos fatores que menos dificultam o tratamento, os maiores percentuais de concordância foram para as questões: chegar à consulta e não ter médico (36,6%), o tempo de espera para consulta é longo e não estar melhorando da pressão (16,9% e 14,1% respectivamente). Exames laboratoriais: glicemia 121,3±43,6 mg/dL, colesterol total 204,8±41,6 mg/dL, HDL 48,5±11,25 mg/dL, VLDL 29,5±15,2 mg/dL, LDL 123,6±39,2 mg/dL, triglicérides 150,1±88 mg/dL, ureia 45,1±16,4 mg/dL e creatinina 1,0±0,5 mg/dL. Houve diminuição significativa (p<0,05) da pressão arterial na MRPA inicial em relação à final 144,9±15,7 vs 140,6±16,8 mmHg para pressão sistólica matutina, 145,7±18,0 vs 141,7±17,5 mmHg para pressão sistólica noturna, 85,8±9,4 vs 83,5±9,6 mmHg para diastólica matutina e 84,5±9,9 vs 81,8±9,3 mmHg para diastólica noturna. Na medida da pressão em casa, diminuição significativa foi observada na comparação das primeira e oitava semanas 144,4±17,3 vs 139,3±15,9 mmHg para sistólica matutina, 144,7±19,8 vs 140,8±17,8 mmHg para sistólica noturna, 86,8±18,8 vs 82,7±10,1mmHg para diastólica matutina, 83,2±10,5 vs 82,2±10,4 mmHg para diastólica noturna. Na medida de consultório também houve diminuição significativa (p<0,05) entre a do início do estudo e o final (157,6±13,6 / 91,4±8,3 vs 146,9±19,9 / 85,1±11,5 mmHg). Dessa forma, a diminuição no percentual de hipertensos controlados foi: 67,6% e 57,7% na MRPA e 73,2% e 70,4% na medida de consultório, para as pressões sistólica e diastólica, respectivamente. A análise multivariada mostrou que o controle da pressão arterial associou-se com: a) sistólica na medida residencial: teste de Morisky e Green (OR: 0,187; IC 95%; 0,57-0,619) e o domínio crenças pessoais do questionário fatores dificultadores da adesão (OR: 0,696; IC 95%; 0,502-0,965); b) diastólica na medida em casa: idade entre 55 e 65 anos (OR: 0,138; IC 95%; 0,030-0,637), idade acima de 65 anos (OR: 0,216; IC 95%; 0,055-0,845 e prática de esportes (OR: 0,179; IC 95%; 0,044-0,730); c) diastólica de consultório: Self Report Questionnaire - SRQ-20 (OR: 8,746; IC 95%; 2,243-34,103), HDL - colesterol < 40 e 40-59 mg/dL (OR: 3,644; IC 95%; 0,338-39,338) e HDL - colesterol 60 mg/dL (OR: 37,323; 95%; 2,079-670,022); d) sistólica e diastólica na MRPA: variável domínio institucional do instrumento fatores dificultadores da adesão (OR: 1,260; IC 95%; 1,036-1,533) e (OR: 1,212; IC 95%; 1,003-1,464). Conclusão: a estratégia de controle da medida da pressão arterial em casa foi eficiente para o aumento do controle da pressão arterial desse grupo de hipertensos. / Introduction Hypertensive patients lack of control has been a challenge for health professional, and home pressure measurement can be a resource to enhance blood pressure control. General aim: To assess the effect of using home pressure measurement on blood pressure control in a group of hypertensive patients from Peruibe SP. Specific aims: 1- To compare the blood pressure control of hypertensive patients submitted to home pressure measurement. 2- To assess the blood pressure control of hypertensive patients, considering home blood pressure monitoring (HBPM) as the pre and post home pressure measurement assessment method. 3- To assess treatment adherence using the Inhibiting Factors of Adherence (IFA) questionnaire and the Morisky and Green test. 4- To identify associations between blood pressure control and biopsychosocial variables, life habits, behaviors and attitudes towards the disease and treatment. Cases and Method: Longitudinal field research combined with a quantitative approach. The study was carried out in Peruíbe-SP, at the Hypertension and Diabetes Referral Center and the medical specialty outpatient clinic. The nurse performed outpatient blood pressure measurement at the start and end of the study. The patient measured blood pressure at home, using a validated automatic device, during 8 weeks, on Monday, Wednesday and Friday mornings (between 6 and 10 a.m.) and nights (between 18 and 22h). Home blood pressure monitoring (HBPM) was performed at the start and end of the study, in week 1 and 10, during 7 days, using the same device, with three measures in the morning (between 6 and 10h) and 3 measures at night (between 18 and 22h), in the sitting position, after a ten-minute rest and using an adequate cuff. Fasting glucose, total cholesterol and fractions, triglycerides, urea and creatinine tests were also performed. Treatment adherence was assessed with the Inhibiting Factors of Adherence (IFA) questionnaire and the Morisky and Green test. The presence of common mental disorders was assessed with the Self Report Questionnaire (SRQ 20), the risk for health damage related to the use of alcoholic beverages with the Alcohol Use Disorders Identification (AUDIT) and social support with the Social Support Scale. Univariate and multivariate analyses were performed. Significance was set at p<0.05. Results: Seventy-one hypertensive patients were studied, with a mean age of 63.3±11 years; 53.5% men; 77.5% white; 77.1% with primary/secondary education; 53.5% retired; 52.1% income 2 minimum wages and non smokers; 19.7% sedentary; body mass index 30.8±5.8 kg/m2; 35.2% alcohol consumers, 43.7% adherent to treatment according to the Morisky and Green test and 32.4% with common non-psychotic mental disorders. On 19 out of 25 questions on the inhibiting factors of adherence form, scores for factors that least hampered treatment exceeded 90%. The highest agreement percentages were for: arriving for a consultation without the presence of a physician (36.6%), long waiting time for a consultation (16.9%) and not achieving blood pressure improvements (14.1%). Laboratory test results were: glucose- 121.3±43.6 mg/dL, total cholesterol 204.8±41.6 mg/dL, HDL-c- 48.5±11.25 mg/dL, VLDL-c- 29.5±15.2 mg/dL, LDL-c- 123.6±39.2 mg/dL, triglycerides- 150.1±88 mg/dL, urea- 45.1±16.4 mg/dL and creatinine- 1.0±0.5 mg/dL. A significant decrease (p<0.05) in blood pressure occurred between initial and final HBPM in the morning (144.9±15.7/85.8±9.4 vs 140.6±16.8/ 83.5±9.6 mmHg) and night period (145.7±18.0/84.5±9.9 vs 141.7±17.5/81.8±9.3 mmHg), as well as in the total average (145.1±16.2/85.0±9.4 vs 141.1±16.4/82.6±9.1 mmH). In home pressure measurement, a significant decrease in systolic pressure also occurred when comparing the first and eight week, measured in the morning (144.4±17.3/86.8±18.8 vs. 139.3±15.9/82.7±10.1 mmHg) and at night (144.7±19.8/83.2±10.5 vs. 140.8±17.8/82.2±10.4 mmHg), and also in the total average (144.4±17.6/85.1±12.2 vs. 140.2±16.2/83.4±9.3 mmHg). A significant decrease (p<0.05) also occurred in the outpatient measurement between the start and end of the study (157.6±13.6/91.4±8.3 vs. 146.9±19.9/85.1±11.5 mmHg). Thus, the decrease in the percentage of controlled hypertensive patients corresponded to: 67.6% and 57.7% in HBPM and 73.2% and 70.4% in outpatient measurement for systolic and diastolic pressure, respectively. Multivariate analysis showed that blood pressure control was associated with the following blood pressure assessments: a) systolic pressure measured at home with Morisky and Green test (OR: 0.187; CI 95%; 0.57-0.619) and the personal beliefs domain in the inhibiting factors of adherence questionnaire (OR: 0.696; CI 95% 0.502-0.965); b) diastolic pressure measured at home with age between 55 and 65 years (OR: 0.138; CI 95%; 0.030-0.637), age over 65 years (OR: 0.216; CI 95%; 0.055-0.845) and doing physical exercise (OR: 0.179; CI 95%; 0.044-0.730); c) outpatient diastolic pressure measure with presence of common mental disorders (OR: 8.746; CI 95%; 2.243-34.103), HDL - cholesterol < 40 and 40-59 mg/dL (OR: 3.644; CI 95%; 0.338-39.338) and HDL - cholesterol 60 mg/dL (OR: 37.323; CI 95%; 2.079-670.022); d) systolic and diastolic pressure in HBPM with institutional domain variable of inhibiting factors of adherence questionnaire (OR: 1.260; CI 95%; 1.036-1.533) and (OR: 1.212; CI 95%; 1.003-1464), respectively. Conclusion: The strategy to have patients measure their blood pressure at home was effect to increase blood pressure control in the group of hypertensive patients under analysis.
109

Jämförelse av portrycksmätning i Uppsalalera mellan portrycksmätare och dissipationstest

Ahlgren Mattsson, David January 2019 (has links)
Portrycket är en viktig parameter för att bestämma jordens egenskaper, såsom dränering, permeabilitet och stabilitet (då portrycket har en påverkan på den effektiva spänningen i jorden). Portrycket kan mätas med portrycksmätare men det kan även mätas under ett Cone penetrating test (CPT) med ett s.k. dissipationstest. Fördelar med ett dissipationstest jämfört med traditionell portrycksmätning skulle vara att det skulle spara tid och pengar, då man slipper trycka ner portrycksmätare och sedan vänta på att få portrycket ifrån dem, istället kan portrycket mätas under sondering med CPT.Detta självständiga arbete har som syfte att jämföra portrycksmätningar mellan portrycksmätning med BAT-spets och dissipationstest under CPT-sondering för att se hur bra mätvärden dissipationstester ger och om de eventuellt kan ersätta portrycksmätare. Fältförsöken av metoderna skedde i Uppsalalera, på en tomt i Kungsängen i Uppsala.Två stationer med BAT-spetsar på 5 meter, 7,5 meter och 10 meters djup sattes ner i leran. Sondering med CPT genomfördes sedan, där borren stoppades på samma djup som BAT-spetsarna. CPT:n stoppades på dessa djup i drygt 24 timmar, för att tillåta det generade portrycket som skapades när borren trycks ner i leran att skingras åt sidan. Jämviktsportrycket kommer vara det portryck som finns kvar efter att det generade portrycket har försvunnit. Portrycken från de två olika metoderna jämfördes sedan för att se hur nära dissipationstestet kommer värdena från portrycksmätningen med BAT-spetsarna.Resultatet av dissipationstesterna blev att inga av dem nådde referensvärdena från BAT-spetsarna efter 24 timmar. Beroende på användningsklass ligger dissipationstesterna inom den tillåtna minsta noggrannheten. Dissipationstest är antagligen inte så praktiskt tillämpbart i jordar med låg permeabilitet. / The pore pressure is an important parameter for determining the properties of thesoil, such as drainage, permeability and stability (since the pore pressure has aneffect on the effective stress in the soil). The pore pressure can be measured withpore pressure gauges but it can also be measured during a Cone penetration test(CPT) with a dissipation test. Advantages of a dissipation test compared tomeasurement with traditional pore pressure gauges would be that it would save timeand money, since you don’t have to press down pore pressure gauges and then waitto get the pore pressure from them, instead the pore pressure can be measuredduring probing with CPT.The purpose of this project is to compare pore pressure measurements betweenpore pressure measurements with BAT-tips and dissipation test during CPT probing,to see how good measured values the dissipation tests will provide and if theyeventually can supersede pore pressure gauges for pore pressure measurements.The field tests of the methods were done in Uppsala clay, on a site in Kungsängen inUppsala.Two stations with BAT-tips at 5 meters, 7.5 meters and 10 meters depth wereinstalled in the clay. Probing with CPT was then carried out, by stopping the CPT atthe same depth as the BAT-tips. Measurements with the CPT were done at thesedepths for just over 24 hours, to allow the generated excess pore pressure createdwhen the cone is pushed into the clay to disperse to the sides. The equilibrium porepressure is the pore pressure that remains after the generated pore pressure hasdissipated. The pore pressure from the two different methods was then compared tosee how close the dissipation test results were to the values from the pore pressuremeasurements with the BAT tips.The result of the dissipation tests was that none of them reached the referencevalues from the BAT-tips after 24 hours. Depending on the chosen application class,the dissipation tests are within the permitted minimum accuracy. Dissipation tests areprobably not practically applicable to soils with low permeability.
110

An Analysis of a Pressure Compensated Control System of an Automotive Vane Pump

Ryan P Jenkins (6331784) 10 June 2019 (has links)
<div>Pressure compensated vane pump systems are an attractive solution in many automotive applications to supply hydraulic power required for cooling, lubrication, and actuation of control elements such as transmission clutches. These systems feature variable displacement vane pumps which offer reductions in parasitic loads on the engine and in wasted hydraulic energy at high engine speeds when compared to traditional fixed displacement supply pumps. However, oscillations in a currently available pressure compensation system limits the achievable performance and therefore the application of this solution.</div><div>This dissertation presents the development and experimental validation of a lumped parameter model in MATLAB/Simulink of a current pressure compensated vane pump system for an automatic transmission oil supply application. An analysis of the performance of this system using the validated pump model and a developed black box control system model reveals that the low cost solenoid valve present in the control circuit to set the regulation pressure limits the achievable bandwidth to 1.84Hz and causes a significant time delay in the response. To address this limitation, as well as eliminate a non-minimum phase zero introduced by the case study’s control circuit architecture, an actively controlled electrohydraulic pressure compensation system is proposed. This proposed system is explored both experimentally and in simulation making use of the accuracy of the presented variable displacement vane pump model. Significant improvements in the achievable system performance are shown with both a simple PI control law (47% reduction in the pressure response time) and an advanced cascaded model following controller based on feedback linearization (58% reduction in the pressure response time). An analysis of these results reveals that implementing the proposed control system with a 5(L/min)/bar proportional valve with a 20Hz at ±100% (60Hz at ±50%) amplitude bandwidth and a PI control law is an economical path to achieving the best performance improvements for this automotive application.</div>

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