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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.
1

Design of a Two-Chamber-NO2-Fluorescence-Cell

Schmid, Volker 30 September 1996 (has links)
Nitrogen oxides control the photochemical production of ozone 03 in the lower atmosphere and influence the concentration of the hydroxyl radical HO in the troposphere. As an important member of the nitrogen oxide family, N02 plays a significant role in serving as the only known source of ozone (through photolysis) in the lower atmosphere and as sink for HO via formation of nitric acid. Therefore, accurate measurements of nitrogen dioxide are essential for the understanding of the processes that determine the distribution of tropospheric ozone and for assessing the impact of human activity on the troposphere. Although reliable and sensitive techniques for the direct measurement of nitric oxide NO have been developed, these results could not be fully applied to direct N02 measurements. The purpose of the present study was to further develop a low pressure laser-excited fluorescence technique for measuring N02 by introducing the idea of a Two-Chamber-Fluorescence-Cell. Theoretical considerations of the performance of such a cell and the flow regime within the cell were done in order to assess the optimum cell design and the conditions for optimum operation. Measurements on a provided two-chambered test cell were done to verify the theoretical predictions made. This test cell has been explored with a Nd:Y AG pumped dye laser (100mW@564nm, 30Hz) and a supplied N02 concentration of lOOppm. The theoretical results suggest that the concept of a Two-Chamber-N02- Fluorescence-Cell yields an improved sensitivity compared to present direct techniques for measuring N02 In addition, experimental results give a better understanding of how to realize the initial idea of an operating Two-Chamber-N02- Fluorescence-Cell.
2

Projeto e fabricação de dispositivo de fixação de cabeçotes e abertura de válvulas em equipamento de medição de Swirl. / Project and manufacturing of a fixation and valve lift device for cylinder heads in a Swirt measurement equipment.

Tanaka, Alexandre Tomio 11 August 2017 (has links)
Neste trabalho pretende-se desenvolver o dispositivo para a fixação de cabeçotes e acionamento de válvulas em um equipamento para medição de swirl, que é um dos movimentos do ar dentro da câmara de combustão nos motores de ignição por compressão. Este desenvolvimento tem como objetivos facilitar a montagem do cabeçote no equipamento e desenvolver o avanço automático das válvulas, visando a redução do tempo total do ensaio. No desenvolvimento, foi feito um comparativo das características e componentes montados nos cabeçotes e nos diferentes modelos que serão testados no equipamento, para que não fossem necessários retrabalhos no cabeçote ou desmontagens de componentes para a realização dos ensaios, abrangendo a maior gama possível de produtos. Foram definidos os métodos de posicionamento do cabeçote no dispositivo e o sistema de fixação. Para garantir a precisão no acionamento das válvulas, foi definido um fuso de esferas recirculantes, acionadas por um motor de passo. O projeto foi concluído e o dispositivo foi fabricado e instalado no equipamento de medição. Testes realizados mostraram resultados de medição de swirl conforme esperado, além da diminuição no tempo total do teste. A partir de observações feitas após a fabricação e os testes no dispositivo, algumas melhorias estão sendo propostas, como, por exemplo, acionamentos por balancins independentes para cada válvula. / In this work, the aim is to develop the device for the fixture of the cylinder head and the valve actuation in a swirl meter test bench. Swirl is a movement inside the combustion chamber in a compression ignition engine. The development aims to facilitate the assembling of the cylinder head in the equipment and develop the valve lift device, focusing in decreasing the total time for the test. Also, the valve actuator shall be able to perform the continuous valve lift in the swirl measurement. During the development of this work, a comparative of the main features and the components assembled in the different cylinder head types to be tested in the equipment was done, to avoid rework or disassembling of components for the test, including the most variety of types. It was defined the positioning method for cylinder head in the device and the fixation system. To ensure the precision in the valve actuation, it was defined a ball screw, driven by a step motor. The project was finalized, manufactured and installed in the measurement equipment. Performed tests have showed results of swirl measurement according to expected, and the total time of test was decreased. After this first project, some improvements are proposed in the device, for example, individual actuation per valve.
3

Measuring rapid kinetics by electroanalytical methods in droplet-based microfluidic devices. / CUHK electronic theses & dissertations collection

January 2011 (has links)
Han, Zuoyan. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2011. / Includes bibliographical references (leaves 75-81). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.
4

Projeto e fabricação de dispositivo de fixação de cabeçotes e abertura de válvulas em equipamento de medição de Swirl. / Project and manufacturing of a fixation and valve lift device for cylinder heads in a Swirt measurement equipment.

Alexandre Tomio Tanaka 11 August 2017 (has links)
Neste trabalho pretende-se desenvolver o dispositivo para a fixação de cabeçotes e acionamento de válvulas em um equipamento para medição de swirl, que é um dos movimentos do ar dentro da câmara de combustão nos motores de ignição por compressão. Este desenvolvimento tem como objetivos facilitar a montagem do cabeçote no equipamento e desenvolver o avanço automático das válvulas, visando a redução do tempo total do ensaio. No desenvolvimento, foi feito um comparativo das características e componentes montados nos cabeçotes e nos diferentes modelos que serão testados no equipamento, para que não fossem necessários retrabalhos no cabeçote ou desmontagens de componentes para a realização dos ensaios, abrangendo a maior gama possível de produtos. Foram definidos os métodos de posicionamento do cabeçote no dispositivo e o sistema de fixação. Para garantir a precisão no acionamento das válvulas, foi definido um fuso de esferas recirculantes, acionadas por um motor de passo. O projeto foi concluído e o dispositivo foi fabricado e instalado no equipamento de medição. Testes realizados mostraram resultados de medição de swirl conforme esperado, além da diminuição no tempo total do teste. A partir de observações feitas após a fabricação e os testes no dispositivo, algumas melhorias estão sendo propostas, como, por exemplo, acionamentos por balancins independentes para cada válvula. / In this work, the aim is to develop the device for the fixture of the cylinder head and the valve actuation in a swirl meter test bench. Swirl is a movement inside the combustion chamber in a compression ignition engine. The development aims to facilitate the assembling of the cylinder head in the equipment and develop the valve lift device, focusing in decreasing the total time for the test. Also, the valve actuator shall be able to perform the continuous valve lift in the swirl measurement. During the development of this work, a comparative of the main features and the components assembled in the different cylinder head types to be tested in the equipment was done, to avoid rework or disassembling of components for the test, including the most variety of types. It was defined the positioning method for cylinder head in the device and the fixation system. To ensure the precision in the valve actuation, it was defined a ball screw, driven by a step motor. The project was finalized, manufactured and installed in the measurement equipment. Performed tests have showed results of swirl measurement according to expected, and the total time of test was decreased. After this first project, some improvements are proposed in the device, for example, individual actuation per valve.
5

Evaluation of the wearable blood pressure measurement devices.

January 2006 (has links)
Xiang Xiaoyan. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2006. / Includes bibliographical references. / Abstracts in English and Chinese. / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Background of Hypertension --- p.1 / Chapter 1.1.1 --- Definition of Blood Pressure --- p.1 / Chapter 1.1.2 --- Hypertension and Its Prevalence --- p.2 / Chapter 1.2 --- Blood Pressure Measurement Techniques --- p.5 / Chapter 1.2.1 --- Invasive Blood Pressure Measurement Techniques --- p.5 / Chapter 1.2.2 --- Non-invasive Blood Pressure Measurement Techniques --- p.6 / Chapter 1.3 --- Accurate BP Measurements --- p.12 / Chapter 1.3.1 --- Error Source for BP Measurement by Conventional Techniques --- p.12 / Chapter 1.3.2 --- Accurate BP Measurement --- p.13 / Chapter 1.4 --- Objectives of the Thesis --- p.15 / Chapter 1.5 --- Organization of the Thesis --- p.16 / References --- p.17 / Chapter Chapter 2 --- Current Standards for the Conventional Blood Pressure Measurement Devices --- p.20 / Chapter 2.1 --- Introduction --- p.20 / Chapter 2.2 --- Current Standards for the Cuff-based BP Measurement Devices --- p.21 / Chapter 2.2.1 --- AAMI Standard --- p.21 / Chapter 2.2.2 --- BHS Protocol --- p.22 / Chapter 2.2.3 --- Other Protocols --- p.23 / Chapter 2.3 --- Comparison of the 2002 AAMI and 1993 BHS Protocols - Protocol Setup --- p.25 / Chapter 2.4 --- Comparison of the 2002 AAMI and 1993 BHS Protocols 一 Accuracy Criteria --- p.29 / Chapter 2.5 --- Relationship between the AAMI Accuracy Criteria and the BHS Grading System --- p.31 / Chapter 2.5.1 --- Theoretical Mapping Relationship --- p.31 / Chapter 2.5.2 --- Application of the Mapping Model: Estimate the BHS Grades from the Reported Sample ME and SD --- p.34 / Chapter 2.5.3 --- Application of the Mapping Model: Explain the Evaluation of the Results from the Clinical Survey by the ESH --- p.36 / Chapter 2.6 --- Discussion --- p.36 / References --- p.40 / Chapter Chapter 3 --- Distribution Analysis of the Blood Pressure Measurement Errors --- p.42 / Chapter 3.1 --- Introduction --- p.42 / Chapter 3.2 --- Error Distribution Estimated from the Published Data --- p.43 / Chapter 3.2.1 --- Methodology --- p.43 / Chapter 3.2.2 --- Data Analysis --- p.44 / Chapter 3.2.3 --- Session Summary --- p.46 / Chapter 3.3 --- Error Distribution Estimated from the Experimental Data --- p.46 / Chapter 3.3.1 --- BP Measurement Error Obtained from Automatic BP Meter --- p.46 / Chapter 3.3.2 --- Distribution Analysis by the Normal Quantile-Quantile Plot --- p.47 / Chapter 3.3.3 --- Background of Student's t Distribution --- p.48 / Chapter 3.3.4 --- Parameter Estimation - Maximum Likelihood Method --- p.50 / Chapter 3.3.5 --- Goodness-of-fit Test - Kolmogorov-Smirnov Test --- p.53 / Chapter 3.3.6 --- Goodness-of-fit Test ´ؤ Chi-Square Test --- p.56 / Chapter 3.4 --- Discussion --- p.63 / References --- p.65 / Chapter Chapter 4 --- A Model Based Study of the Parameters Used by Existing Standards --- p.67 / Chapter 4.1 --- Introduction --- p.67 / Chapter 4.2 --- Background of Method Comparison Study --- p.68 / Chapter 4.2.1 --- Four Areas in Method Comparison Study --- p.68 / Chapter 4.2.2 --- Analysis of Previous Methodology and Statistical Parameters --- p.70 / Chapter 4.3 --- Theoretical Mapping Relationship: Based on the General t Distribution --- p.72 / Chapter 4.3.1 --- "Relationship among CP5, CP10 and CP15 in Each Grade for the 1993 BHS Protocol" --- p.76 / Chapter 4.3.2 --- Relationships between the Criteria in Each Grade for the 1993 BHS Protocol and the AAMI Standard --- p.77 / Chapter 4.3.3 --- Comparison of Parameters --- p.80 / Chapter 4.4 --- Mean of the Absolute Errors (MAE) and Its Estimation --- p.81 / Chapter 4.4.1 --- The Relationship between MAE and Other Parameters --- p.81 / Chapter 4.4.2 --- Analysis of the Example Data --- p.84 / Chapter 4.4.3 --- Estimation of MAEt --- p.84 / Chapter 4.5 --- Discussion --- p.88 / References --- p.90 / Chapter Chapter 5 --- Experimental Study and an Evaluation Protocol Proposed for the Wearable BP Measurement Devices --- p.92 / Chapter 5.1 --- Introduction --- p.92 / Chapter 5.2 --- Description of the Experiment --- p.93 / Chapter 5.3 --- Data Analysis --- p.95 / Chapter 5.3.1 --- Data Used for the Study --- p.95 / Chapter 5.3.2 --- Error Distribution Analysis --- p.96 / Chapter 5.3.3 --- Evaluation of the Automatic BP Meter and the PTT-Based BP Measurement Device by AAMI and 1993 BHS Standards --- p.99 / Chapter 5.3.4 --- Evaluation the Automatic BP Meter and the PTT-Based BP Measurement Device by the Proposed Parameter --- p.101 / Chapter 5.4 --- Proposed Evaluation Procedure --- p.101 / Chapter 5.4.1 --- Introduction --- p.101 / Chapter 5.4.2 --- Determination of Parameters and Criteria --- p.102 / Chapter 5.4.3 --- Proposed Evaluation Procedure --- p.103 / Chapter 5.5 --- Discussion --- p.105 / References --- p.108 / Chapter Chapter 6 --- Conclusion and Future Work --- p.110 / Chapter 6.1 --- Conclusion and Major Contributions --- p.110 / Chapter 6.2 --- Future Works --- p.113 / References --- p.115 / Appendix A Deviation of Some Equations --- p.116 / Chapter A.1 --- CP for Certain Limit of L as a Function of ME and SD --- p.116 / Chapter A.2 --- MAE as a Function of Location and Scale Parameters --- p.119 / Chapter A.3 --- "Relationship between ME, MAE and Root Mean Squared Error (RMSE) if the error distribution is unknown" --- p.121 / Appendix B List of Publications and Awards Related to This Study --- p.123
6

Effects of autonomic nervous system on the pulse transit time-based blood pressure estimation. / CUHK electronic theses & dissertations collection

January 2013 (has links)
心血管疾病持續成為世界上第一大死亡原因。在眾多危險因素中,動脈血壓,尤其是夜間血壓和血壓變化率,是心血管疾病發病率和死亡率的關鍵指標。 / 由於需要用到充氣式袖帶,現有的血壓測量技術只能提供瞬時血壓,並且使用起來極不舒適。因此,本文致力於研究另一種無袖帶式血壓測量方法。此方法的原理基於血壓波在血管上的傳導速度,即脈搏波傳導速度(PWV)取決於血壓作用下的血管力學特性。因此,血壓可以從脈搏波傳導速度,或者其倒數:脈搏波傳輸時間(PTT)估計得到。由於脈搏波傳導時間可以方便的從心電信號及光電容積描記信號獲取,這種新型的無袖帶式血壓測量技術近年來備受關注。 / 現有的基於脈搏波傳輸時間的血壓估計方法建立於一個被動的,薄壁的和均質的血管模型。但是,真實的血管卻是由彈性蛋白,膠原纖維和平滑肌共同組成的具有特殊層次結構的管道。事實上,以往許多研究已經表明了血管緊張度(VSM tone),即血管壁平滑肌細胞的激活程度,能顯著改變血管力學特性進而使脈搏波傳輸時間與血壓的關係惡化。特別地,血管緊張度主要受控于自主神經系統,尤其是交感神經系統。因此,本論文的目的在於研究自主神經系統對基於脈搏波傳輸時間的血壓估計的影響。 / 首先,基於血管微結構力學模型和Bramwell-Hill公式,本文建立了一個基於血管組分的脈搏波傳輸時間-血壓模型。并在此基礎上,推導出一個融合了血管結構和功能特性的解析數學公式來表徵脈搏波傳導時間和血壓的關係。仿真結果顯示,隨著血管緊張度增高,脈搏波傳輸時間-血壓曲綫會移向右上方,造成滯變現象(hysteresis)。 / 其次,爲了研究自主神經系統對血壓,脈搏波傳輸時間及心率的調節機制,本文利用時頻分析技術,對來自9個健康測試者跑步運動前後的實驗數據進行了分析。結果顯示,僅心率這一參數表現出運動中首先迷走神經活動減弱,然後交感神經增強的機制。此外,分析結果表明脈搏波傳輸時間與血壓的關係是頻率相關的。 / 爲了進一步研究自主神經系統在吞咽動作過程中對心血管參數的調控作用,本文設計了喝水實驗。對32個健康測試者的實驗數據分析結果表明,在喝水過程中,心率和血壓顯著上升,脈搏波傳輸時間顯著下降。另一方面,基於之前脈搏波傳輸時間與血壓的頻變關係的研究發現,本文設計了一種新的基於脈搏波傳輸時間,利用頻段特定的序列技術,來估計壓力反射敏感性(BRS)的新方法,並利用喝水實驗數據進行了驗證。結果顯示,利用此方法估計和利用傳統的利用血壓計算出的壓力反射敏感性具有高相關性(喝水前,中,后過程中,相關係數分別為0.90,0.70和0.81)。 / 最後,爲了驗證自主神經系統調控下的血管緊張度對脈搏波傳輸時間和血壓關係的影響,本文對來自46名測試者,其中包括17名心血管疾病患者,在人體仰臥姿態下的漸進式腳踏車運動實驗中的數據進行了分析。結果證實了仿真實驗中顯示的脈搏波傳輸時間和血壓的滯變現象。另外,本文提出了兩個新型量化指標衡量此滯變現象,即AreaN和ΔSBP20。結果顯示,相比于健康人,心血管疾病患者的滯變現象幅度顯著減弱,這與此類患者通常伴隨有交感神經系統過度活躍相關。基於以上發現,本文進一步提出利用AreaN和ΔSBP20來評估交感神經系統功能的建議。 / 綜上所述,本論文從理論和實驗的雙重角度研究了自主神經系統對脈搏波傳輸時間和血壓關係的影響。此工作將有利於提高基於脈搏波傳輸時間的血壓估計技術的準確度,并進一步對控制心血管疾病做出貢獻。 / Cardiovascular diseases (CVDs) remain the number one cause of death worldwide. Amongst various risk factors, arterial blood pressure (BP), especially BP measured during nighttime, and BP variability are major indicators of cardiovascular morbidity and mortality. / Most of the state-of-the-art BP meters are designed with an inflatable cuff, which provide snapshots of BP and are uncomfortable during measurements. An alternative cuffless BP measurement approach is therefore studied in this work. The estimation principle is derived based on the fact that velocity of a pressure wave propagating along an artery, i.e., pulse wave velocity (PWV) is related to the pressure-dependent mechanical property of the artery. Thus, BP can be possibly estimated from PWV, or its reciprocal, pulse transit time (PTT), which can be conveniently acquired from electrocardiogram and photoplethysmogram without using an inflatable cuff. / The current PTT-based BP estimation was built on a model that assumes the artery to be a passive, thin-wall and homogeneous tube. However, arterial wall in reality exhibits a specific layered structure and consists of elastin, collagen fibers and smooth muscles. In fact, the PTT-BP relationship was found by many studies to be easily deteriorated by vasoconstriction/dilation, which reflects the vascular smooth muscle (VSM) activation level, i.e., VSM tone. In particular, innervating most blood vessels, the autonomic nervous system (ANS), primarily sympathetic nervous system, plays an important role in determining the arterial mechanical behavior thus PTT-BP relationship via regulating the VSM tone. It is therefore the aim of this thesis to investigate the effects of ANS on the PTT-based BP estimation. / Firstly, a constituent-based PTT-BP model was developed in the thesis, based on the micro-structurally motivated arterial mechanical model and Bramwell-Hill equation. Specifically, analytic PTT-BP relationship incorporating arterial structural and functional properties was deduced. Theoretical effects of various arterial properties on the relationship have been evaluated by simulation. The results revealed that PTT-BP curve will shift to the top right when VSM tone elevates, producing PTT-BP hysteresis. / Next, the mechanism of regulation of BP, PTT as well as heart rate (HR) by ANS was evaluated in 9 normotensive subjects in treadmill exercise by using time-frequency technique. Vagal withdrawal and subsequent sympathetic activity enhancement by exercise have been observed in only HR. In addition, the results indicate a frequency-dependent PTT-BP relationship. / Then we conducted water drinking experiments in a total of 32 healthy subjects to investigate the ANS controlled cardiovascular responses by the act of swallowing. Significant increment in HR and BP, and decrease in PTT were observed during drinking. On the other hand, considering the frequency-dependent nature of PTT-BP relationship, a novel method that estimates baroreflex sensitivity (BRS) from PTT based on the band-specified sequence technique has been proposed. The results showed high correlations between BRS estimated from BP and PTT. (γ=0.90, 0.70 and 0.81 before, during and after drinking respectively). / Lastly, the effects of ANS mediated VSM tone on the PTT-BP relationship were validated in 46 subjects including 17 patients with CVDs in graded bicycle exercise stress test in supine position. The results demonstrated PTT-BP hysteresis as predicted by the simulation. Furthermore, two novel parameters, i.e., AreaN and ΔSBP20 were proposed to evaluate the hysteresis phenomenon. Significant attenuation was observed in CVD patients with sympathetic overactivity. The two quantifications were proposed accordingly to be indices for assessing sympathetic function. / To conclude, this work addressed the effects of ANS on the PTT-BP relationship from both theoretical and experimental aspects. The work can help to improve the accuracy of PTT-based BP estimation and CVD control. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Liu, Qing. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2013. / Includes bibliographical references. / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts also in Chinese. / Abstract --- p.i / Acknowledgement --- p.v / List of figures --- p.vi / List of tables --- p.x / List of abbreviations --- p.xi / Chapter Chapter 1. --- Introduction --- p.1 / Chapter 1.1. --- Current Status of Blood Pressure Management --- p.1 / Prevalence of Cardiovascular Diseases --- p.1 / Healthcare System Transformation --- p.2 / Blood Pressure A Crucial Role in CVD Control --- p.4 / Chapter 1.2. --- Overview of Blood Pressure Measurement Techniques --- p.7 / Chapter 1.3. --- Motivations and Objectives of the Thesis --- p.15 / Chapter 1.4. --- Organization of the Thesis --- p.16 / References: --- p.17 / Chapter Chapter 2. --- Basics of Cardiovascular System, Autonomic Nervous System and PTT-BP Relationship --- p.20 / Chapter 2.1. --- Cardiovascular System --- p.20 / Heart Physiology --- p.20 / Arterial Physiology --- p.24 / Chapter 2.2. --- Autonomic Nervous System --- p.35 / Autonomic Histology and Pharmacology --- p.35 / Autonomic Nervous Control of Cardiovascular System --- p.37 / Assessment of ANS Activity --- p.41 / Chapter 2.3. --- PWV and Its Relationship with BP --- p.43 / Pulse Wave Velocity --- p.44 / PWV-BP Relationship --- p.50 / Chapter 2.4. --- Section Summary --- p.54 / References: --- p.55 / Chapter Chapter 3. --- A Model-based Study on the Effects of Arterial Properties on the Relationship between Pulse Transit Time and Blood Pressure --- p.62 / Chapter 3.1. --- Introduction to Constitutive Modeling of Arteries --- p.62 / Experimental Methods --- p.63 / Modeling of Mechanical Behavior: Pressure-Radius Relationship --- p.64 / Chapter 3.2. --- A Novel Constitutive Model of the Relationship between PTT and BP --- p.76 / Chapter 3.3. --- Simulation Study of Effects of Arterial Properties on the PTT-BP Relationship --- p.82 / Chapter 3.4. --- Section Summary --- p.93 / References: --- p.94 / Chapter Chapter 4. --- Evaluation Study on the Autonomic Nervous System Control of Heart Rate, Blood Pressure and Pulse Transit Time Before and After Dynamic Exercise --- p.96 / Chapter 4.1. --- Introduction --- p.96 / Chapter 4.2. --- Methodology --- p.98 / Experiment Protocol --- p.98 / Signal Processing and Spectral Estimation --- p.99 / Chapter 4.3. --- Results --- p.101 / Chapter 4.4. --- Discussion --- p.104 / Chapter 4.5. --- Section Summary --- p.108 / References: --- p.110 / Chapter Chapter 5. --- Investigation on Autonomic Nervous System Control of Heart Rate, Blood Pressure and Pulse Transit Time During Water Drinking --- p.113 / Chapter 5.1. --- Responses of HR, BP and PTT during Water Drinking --- p.113 / Chapter 5.1.1. --- Introduction --- p.113 / Chapter 5.1.2. --- Methodology and Results --- p.115 / Chapter 5.1.3. --- Discussion and Conclusion --- p.118 / Chapter 5.2. --- Potential Application of PTT in Baroreflex Sensitivity Assessment --- p.121 / Chapter 5.2.1. --- Introduction --- p.121 / Chapter 5.2.2. --- Methodology --- p.122 / Chapter 5.2.3. --- Discussion and Conclusion --- p.125 / Chapter 5.3. --- Section Summary --- p.127 / References: --- p.129 / Chapter Chapter 6. --- Experimental Validation of the ANS Effects on the Relationship between Pulse Transit Time and Blood Pressure in Human Stress Test --- p.131 / Chapter 6.1. --- Introduction --- p.131 / Chapter 6.2. --- Methodology --- p.133 / Chapter 6.3. --- Results --- p.137 / Chapter 6.4. --- Discussion and Conclusion --- p.139 / Chapter 6.5. --- Section Summary --- p.144 / References: --- p.145 / Chapter Chapter 7. --- Conclusions and Suggestions for Future Work --- p.148 / Chapter 7.1. --- Summary --- p.148 / Chapter 7.1.1. --- A model-based study on the effects of arterial properties on the PTT-BP relationship --- p.148 / Chapter 7.1.2. --- Evaluation study on the ANS control of HR, BP and PTT before and after dynamic exercise --- p.149 / Chapter 7.1.3. --- Investigation on ANS control of HR, BP and PTT during water drinking --- p.150 / Chapter 7.1.4. --- Experimental validation of the ANS mediated VSM tone on the PTT-BP relationship --- p.151 / Chapter 7.2. --- Suggestions for Future Work --- p.152 / Chapter 7.2.1. --- Modifications on the constituent-based PTT-BP model --- p.152 / Chapter 7.2.2. --- Improvement of PTT-based BP estimation by considering VSM tone effects --- p.153 / Chapter 7.2.3. --- Improvement of PTT-based BP estimation by considering the frequency-dependent PTT-BP relationship --- p.154 / Chapter 7.2.4. --- Validation of the PTT-BP hysteresis quantifications to be indicators of sympathetic function --- p.154 / References: --- p.155 / Appendix --- p.156 / List of Publications --- p.156
7

Physical and Electrical Characterization of Triethanolamine Based Sensors for NO₂ Detection and the Influence of Humidity on Sensing Response

Peterson, Zachariah Marcus 01 January 2011 (has links)
Triethanolamine (TEA) is a semiconducting polymer which exhibits a resistance change when exposed to various gases. The polymer also exhibits a number of reactions with nitrogen dioxide, with the reaction products being heavily dependent on the presence or absence of water vapor. Previous studies have attempted the incorporation of a TEA-carbon nanoparticle composite as the active sensing layer in a chemresistive sensor for detection of NO₂. The incorporation of carbon nanoparticles in the polymer nanocomposite was thought to amplify the sensor's response. There are a number of chemical reactions that can occur between TEA and NO₂, with the reaction products being heavily dependent on the presence and amount of water vapor in the environment. Because of this influence, it becomes necessary to know to what degree the presence of water vapor interferes with the sensing response. In this work we show that the sensor exhibits a reversible resistance change as background humidity changes. This sensitivity to humidity changes is so large that it renders undetectable any resistance change that could be caused by the reaction of TEA with NO₂. Furthermore, we show that the presence of low levels of NO₂ do not interfere with adsorption of water vapor. The detection mechanism is based on measuring resistance changes in the TEA film due to the adsorption/desorption of water vapor. The sensing response can be described by Langmuir adsorption by using a site-based model for the polymer film resistance. Breakdown of the polymer film over time due to continuous adsorption of water vapor, as well as photodegradation of the polymer film, will be discussed. SEM images will also be presented showing growth of crystallites on the electrode walls, as well as experimental results demonstrating degradation of the sensing film during sensor operation.
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[en] STUDY ABOUT MARITIME OIL EXPORTS: METROLOGICAL ASPECT / [pt] ESTUDO SOBRE A EXPORTAÇÃO MARÍTIMA DE PETRÓLEO: ASPECTO METROLÓGICO

ROBERTO DA COSTA CARDOSO 07 January 2015 (has links)
[pt] Por muito tempo, os sistemas de medição dinâmica de petróleo não foram usados para a transferência de custódia. Eles eram utilizados basicamente para fins operacionais, como detectar vazamentos e transferências internas. O aumento progressivo dos preços do barril de petróleo exigiu das medições de petróleo uma incerteza cada vez menor, o que provocou o desenvolvimento de novas tecnologias que resultaram em sistemas dinâmicos de medição de alta precisão a serem utilizados na transferência de custódia. Nesta pesquisa foi avaliada a substituição das medições estáticas por medições dinâmicas no faturamento de exportações marítimas de petróleo, com o objetivo de agilizar as operações de carregamento de navios em píeres diminuindo a indisponibilidade dos recursos logísticos envolvidos, de minimizar a exposição da companhia a perdas financeiras devido a faturamentos errôneos e de verificar que essa diminuição da exposição justifica o investimento em sistemas de medição dinâmica. Foram descritas as medições de tanques de terra, as medições de tanques de navio e os sistemas de medição dinâmica, avaliando procedimentos, equipamentos, além de restrições, problemas e incertezas associadas a cada método. Foi dada atenção especial aos procedimentos de arqueação de tanques para armazenamento de granéis líquidos, comparando procedimentos utilizados no Brasil pelo Inmetro aos requisitos da Norma ISO -7507, e a rastreabilidade metrológica dos equipamentos de medição em relação aos procedimentos utilizados na sua calibração. / [en] For many years, dynamic measurement systems have not been used in the petroleum industry for custody transfer applications, only for operational reasons like detecting leaks and internal transfers. The progressive growth of crude oil prices required measurements with a smaller uncertainty, leading to developing news technologies, resulting in high accuracy flow meters to be used in custody transfer. The main objective of this research was evaluate the replacement of static measurements by dynamic measurements in oil exports sales in order to speed up the loading of vessels, decreasing the unavailability of logistical resources involved, to minimize the company s exposure to economic losses due to erroneous bill of ladings and verify if this justifies the investment in dynamic measurement systems. This research has discussed a number of issues associated with the uncertainty of the shore tanks, vessels tanks and dynamic measurements, evaluating procedures, equipment, and restrictions, problems and accuracy associated with each method. It also included a discussion about the difference between calibration of vertical cylindrical tanks procedures used in Brazil by Inmetro and the requirements of ISO -7507, and about traceability of measuring equipment calibration.

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