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

Thesis (MSc)--Stellenbosch University, 2004. / ENGLISH ABSTRACT: Any branch in science experiences measurement error to some extent. This maybe due to conditions under which measurements are taken, which may include the subject, the observer, the measurement instrument, and data collection method. The inexactness (error) can be reduced to some extent through the study design, but at some level further reduction becomes difficult or impractical. It then becomes important to determine or evaluate the magnitude of measurement error and perhaps evaluate its effect on the investigated relationships. All this is particularly true for blood pressure measurement. The gold standard for measunng blood pressure (BP) is a 24-hour ambulatory measurement. However, this technology is not available in Primary Care Clinics in South Africa and a set of three mercury-based BP measurements is the norm for a clinic visit. The quality of the standard combination of the repeated measurements can be improved by modelling the measurement error of each of the diastolic and systolic measurements and determining optimal weights for the combination of measurements, which will give a better estimate of the patient's true BP. The optimal weights can be determined through the method of structural equations modelling (SEM) which allows a richer model than the standard repeated measures ANOVA. They are less restrictive and give more detail than the traditional approaches. Structural equations modelling which is a special case of covariance structure modelling has proven to be useful in social sciences over the years. Their appeal stem from the fact that they includes multiple regression and factor analysis as special cases. Multi-type multi-time (MTMT) models are a specific type of structural equations models that suit the modelling of BP measurements. These designs (MTMT models) constitute a variant of repeated measurement designs and are based on Campbell and Fiske's (1959) suggestion that the quality of methods (time in our case) can be determined by comparing them with other methods in order to reveal both the systematic and random errors. MTMT models also showed superiority over other data analysis methods because of their accommodation of the theory of BP. In particular they proved to be a strong alternative to be considered for the analysis of BP measurement whenever repeated measures are available even when such measures do not constitute equivalent replicates. This thesis focuses on SEM and its application to BP studies conducted in a community survey of Mamre and the Mitchells Plain hypertensive clinic population. / AFRIKAANSE OPSOMMING: Elke vertakking van die wetenskap is tot 'n minder of meerdere mate onderhewig aan metingsfout. Dit is die gevolg van die omstandighede waaronder metings gemaak word soos die eenheid wat gemeet word, die waarnemer, die meetinstrument en die data versamelingsmetode. Die metingsfout kan verminder word deur die studie ontwerp maar op 'n sekere punt is verdere verbetering in presisie moeilik en onprakties. Dit is dan belangrik om die omvang ven die metingsfout te bepaal en om die effek hiervan op verwantskappe te ondersoek. Hierdie aspekte is veral waar vir die meting van bloeddruk by die mens. Die goue standaard vir die meet van bloeddruk is 'n 24-uur deurlopenee meting. Hierdie tegnologie is egter nie in primêre gesondheidsklinieke in Suid-Afrika beskikbaar nie en 'n stel van drie kwik gebasseerde bloedrukmetings is die norm by 'n kliniek besoek. Die kwaliteit van die standard kombinasie van die herhaalde metings kan verbeter word deur die modellering van die metingsfout van diastoliese en sistoliese bloeddruk metings. Die bepaling van optimale gewigte vir die lineêre kombinasie van die metings lei tot 'n beter skatting van die pasiënt se ware bloedruk. Die gewigte kan berekening word met die metode van strukturele vergelykings modellering (SVM) wat 'n ryker klas van modelle bied as die standaard herhaalde metings analise van variansie modelle. Dié model het minder beperkings en gee dus meer informasie as die tradisionele benaderings. Strukurele vergelykings modellering wat 'n spesial geval van kovariansie strukturele modellering is, is oor die jare nuttig aangewend in die sosiale wetenskap. Die aanhang is die gevolg van die feit dat meervoudige lineêre regressie en faktor analise ook spesiale gevalle van die metode is. Meervoudige-tipe meervoudige-tyd (MTMT) modelle is 'n spesifieke strukturele vergelykings model wat die modellering van bloedruk pas. Hierdie tipe model is 'n variant van die herhaalde metings ontwerp en is gebaseer op Campbell en Fiske (1959) se voorstel dat die kwaliteit van verskillende metodes bepaal kan word deur dit met ander metodes te vergelyk om sodoende sistematiese en stogastiese foute te onderskei. Die MTMT model pas ook goed in by die onderliggende fisiologies aspekte van bloedruk en die meting daarvan. Dit is dus 'n goeie alternatief vir studies waar die herhaalde metings nie ekwivalente replikate is nie. Hierdie tesis fokus op die strukturele vergelykings model en die toepassing daarvan in hipertensie studies uitgevoer in die Mamre gemeenskap en 'n hipertensie kliniek populasie in Mitchells Plain.

Chan Ka Wing. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2002. / Includes bibliographical references. / Abstracts in English and Chinese. / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Objectives --- p.1 / Chapter 1.2 --- Definitions --- p.2 / Chapter 1.2.1 --- Definition of blood pressure --- p.2 / Chapter 1.2.2 --- Definition of hypertension --- p.3 / Chapter 1.3 --- Problems related to hypertension --- p.4 / Chapter 1.4 --- The importance of measuring blood pressure --- p.4 / Chapter 1.4.1 --- Self-measurement of blood pressure --- p.5 / Chapter 1.4.2 --- Ambulatory blood pressure measurement --- p.5 / Chapter 1.5 --- Review of blood pressure measurement techniques --- p.7 / Chapter 1.5.1 --- The invasive method --- p.7 / Chapter 1.5.2 --- Noninvasive methods --- p.8 / Chapter 1.6 --- Review of currently available blood pressure meters --- p.15 / Chapter 1.7 --- Prevalence of hypertension --- p.19 / Chapter 1.7.1 --- Hong Kong --- p.19 / Chapter 1.7.2 --- Worldwide --- p.20 / Chapter 1.8 --- The market for blood pressure meters --- p.21 / Chapter 1.9 --- Organization of the thesis --- p.22 / References --- p.24 / Chapter Chapter 2 --- Measurement of the ECG-PPG interval --- p.30 / Chapter 2.1 --- Introduction --- p.30 / Chapter 2.1.1 --- Pulse transit time (PTT) --- p.30 / Chapter 2.1.2 --- Electrocardiogram (ECG) --- p.36 / Chapter 2.1.2.1 --- Measurement of the ECG signal --- p.37 / Chapter 2.1.3 --- Photoplethysmography (PPG) --- p.38 / Chapter 2.1.3.1 --- Measurement of the PPG signal --- p.41 / Chapter 2.1.4 --- Measurement of blood pressure by ECG-PPG interval --- p.43 / Chapter 2.2 --- Source of errors for measurement of the ECG-PPG interval --- p.44 / Chapter 2.2.1 --- Effects of variability of ECG-PPG intervals --- p.44 / Chapter 2.2.2 --- Effects of bending the arm --- p.49 / Chapter 2.2.3 --- Effects of an external force --- p.54 / Chapter 2.3 --- Conclusion --- p.60 / References --- p.62 / Chapter Chapter 3 --- Cuffless and Noninvasive Measurement of Blood Pressure --- p.68 / Chapter 3.1 --- Introduction --- p.68 / Chapter 3.2 --- Effects of subject-dependent calibration --- p.74 / Chapter 3.3 --- Effects of different time intervals --- p.81 / Chapter 3.4 --- The impact of using different Q-P intervals --- p.96 / Chapter 3.5 --- Real-time measurement of blood pressure --- p.104 / Chapter 3.6 --- Conclusion --- p.108 / References --- p.110 / Chapter Chapter 4 --- Motion Artifact Reduction from PPG Recordings in Ambulatory Blood Pressure Measurement --- p.114 / Chapter 4.1 --- Introduction --- p.114 / Chapter 4.2 --- Previous works --- p.115 / Chapter 4.3 --- Theory --- p.116 / Chapter 4.3.1 --- The adaptive filter --- p.117 / Chapter 4.3.2 --- Variation of step-size parameters --- p.119 / Chapter 4.3.3 --- Effects of filter length --- p.120 / Chapter 4.4 --- Experiment --- p.121 / Chapter 4.5 --- Results --- p.123 / Chapter 4.6 --- Discussion --- p.131 / Chapter 4.7 --- Conclusion --- p.133 / References --- p.135 / Chapter Chapter 5 --- Measurement of Blood Pressure using the PPG signal --- p.138 / Chapter 5.1 --- Introduction --- p.138 / Chapter 5.2 --- Theory --- p.138 / Chapter 5.3 --- Experiment --- p.142 / Chapter 5.3.1 --- Multiple linear regression (MLR) --- p.142 / Chapter 5.3.2 --- Artificial neural networks (ANNs) --- p.146 / Chapter 5.3.3 --- Results --- p.149 / Chapter 5.3.4 --- Discussion --- p.152 / Chapter 5.4 --- The implementation of the Q-P interval --- p.153 / Chapter 5.4.1 --- Results --- p.154 / Chapter 5.4.2 --- Discussion --- p.156 / Chapter 5.5 --- Conclusion --- p.157 / References --- p.158 / Chapter Chapter 6 --- Conclusion and Future Studies --- p.160 / Chapter 6.1 --- Major contributions --- p.160 / Chapter 6.2 --- Future studies --- p.162 / References --- p.165 / Appendix I --- p.166

Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 1981. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING. / Bibliography: leaves 68-69. / by Mark Johnson. / M.S.

Thesis (B.S.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 1979. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING. / Includes bibliographical references. / by Suzanne Marie Burzyk. / B.S.

Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1981. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING. / Bibliography: leaves 125-128. / by Barry Leonard Wyshogrod. / M.S.

Lee Chi Man. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2004. / Includes bibliographical references (leaves 112-121). / Abstracts in English and Chinese. / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Objectives --- p.1 / Chapter 1.2 --- Blood Pressure --- p.2 / Chapter 1.3 --- Hypertension --- p.3 / Chapter 1.3.1 --- Definition of Hypertension --- p.3 / Chapter 1.3.2 --- Causes and Symptoms of Hypertension --- p.3 / Chapter 1.3.3 --- Complication of Hypertension --- p.4 / Chapter 1.3.4 --- Prevalence of Hypertension --- p.4 / Chapter 1.4 --- Blood Pressure Measurement --- p.5 / Chapter 1.4.1 --- History --- p.5 / Chapter 1.4.2 --- Techniques and Methods --- p.7 / Chapter 1.4.3 --- Current Devices --- p.13 / Chapter 1.5 --- Organization of the Thesis --- p.16 / Chapter Chapter 2 --- Theory --- p.18 / Chapter 2.1 --- Introduction --- p.18 / Chapter 2.2 --- Blood Rheology --- p.18 / Chapter 2.2.1 --- Blood Composition --- p.18 / Chapter 2.2.2 --- Flow Properties of Blood --- p.19 / Chapter 2.2.3 --- Blood Vessels --- p.21 / Chapter 2.3 --- Principle of the PTT-Based Blood Pressure Measurement --- p.22 / Chapter 2.3.1 --- Wave Propagation in Blood Vessels --- p.22 / Chapter 2.3.2 --- Pulse Transit Time (PTT) --- p.27 / Chapter 2.3.3 --- Blood Pressure Measurement Based on PTT --- p.31 / Chapter 2.4 --- Effects of Temperature on Blood Pressure --- p.34 / Chapter 2.4.1 --- Human Body Temperature Regulation --- p.34 / Chapter 2.4.2 --- Physiological Responses to Decreased Temperature --- p.36 / Chapter 2.4.3 --- Effects of Temperature on Blood Pressure --- p.38 / Chapter 2.5 --- Possible Effects of Temperature on PTT-Based Blood Pressure Measurement --- p.47 / Chapter 2.5.1 --- Windkessel Model --- p.47 / Chapter 2.5.2 --- Phase Velocity --- p.49 / Chapter 2.5.3 --- Effects of temperature on PTT --- p.52 / Chapter 2.5.4 --- Possible Effects of temperature on PTT-based Blood Pressure Measurement --- p.53 / Chapter 2.6 --- Conclusion --- p.54 / Chapter Chapter 3 --- Algorithms in Calculating Pulse Transit Time: Wavelet-Based and Derivative-Based --- p.55 / Chapter 3.1 --- Introduction --- p.55 / Chapter 3.1.1 --- Wavelet Transform (WT) --- p.56 / Chapter 3.1.2 --- Wavelet Transform Modulus Maxima (WTMM) --- p.58 / Chapter 3.2 --- Experiment --- p.60 / Chapter 3.2.1 --- Subjects --- p.60 / Chapter 3.2.2 --- Equipment and Sensors --- p.61 / Chapter 3.2.3 --- Protocol --- p.61 / Chapter 3.3 --- Methods --- p.62 / Chapter 3.3.1 --- Wavelet-Based Algorithm of PTT Calculation --- p.62 / Chapter 3.3.2 --- Derivative-Based Algorithm of PTT Calculation --- p.65 / Chapter 3.3.3 --- PTT-Based Blood Pressure Estimation --- p.67 / Chapter 3.4 --- Results --- p.68 / Chapter 3.5 --- Discussion --- p.70 / Chapter 3.6 --- Conclusion --- p.72 / Chapter Chapter 4 --- Effects of Ambient Temperature on PTT-Based Blood Pressure Estimation --- p.74 / Chapter 4.1 --- Introduction --- p.74 / Chapter 4.2 --- Experiment --- p.74 / Chapter 4.2.1 --- Subjects --- p.74 / Chapter 4.2.2 --- Equipment --- p.75 / Chapter 4.2.3 --- Protocol --- p.76 / Chapter 4.3 --- Methods --- p.77 / Chapter 4.3.1 --- Features of Photoplethysmographic Signals --- p.78 / Chapter 4.3.2 --- Calculation of Pulse Transit Time (PTT) --- p.78 / Chapter 4.4 --- Results --- p.79 / Chapter 4.4.1 --- "Effects of Ambient Temperature on Blood Pressure, Heart Rate and Finger Skin Temperature" --- p.79 / Chapter 4.4.2 --- Effects of Ambient Temperature on the Features of Photoplethysmographic Signals --- p.82 / Chapter 4.4.3 --- Effects of Ambient Temperature on Pulse Transit Time --- p.84 / Chapter 4.4.4 --- PTT-Based Blood Pressure Estimation --- p.85 / Chapter 4.4.6 --- Evaluation of the Modified Equations of the PTT-Based Blood Pressure Measurement Approach --- p.89 / Chapter 4.5 --- Discussion --- p.94 / Chapter 4.6 --- Conclusion --- p.98 / Chapter Chapter 5 --- Effects of Local Temperature on PTT-Based Blood Pressure Estimation --- p.99 / Chapter 5.1 --- Introduction --- p.99 / Chapter 5.2 --- Methods --- p.99 / Chapter 5.3 --- Results --- p.100 / Chapter 5.3.1 --- "Effects of Local Temperature on Blood Pressure, Heart Rate and Finger Skin Temperature" --- p.100 / Chapter 5.3.2 --- Effects of Local Temperature on Pulse Transit Time --- p.102 / Chapter 5.3.3 --- Effects of Local Temperature on the Features of Photoplethysmographic Signal --- p.103 / Chapter 5.3.4 --- Effects of Local Temperature on PTT-Based Blood Pressure Estimation --- p.104 / Chapter 5.4 --- Discussion --- p.105 / Chapter 5.5 --- Conclusion --- p.107 / Chapter Chapter 6 --- Conclusion and Future Study --- p.108 / Chapter 6.1 --- Major Contributions --- p.108 / Chapter 6.2 --- Future Study --- p.110 / References --- p.112 / Chapter Appendix A --- Motion Artifact Reduction from PPG signal Based on a Wavelet Approach --- p.122 / Chapter A.l --- Introduction --- p.122 / Chapter A.1.1 --- Motion Artifact --- p.122 / Chapter A.1.2 --- Stationary Wavelet Transform (SWT) --- p.123 / Chapter A.2 --- Experiment --- p.124 / Chapter A.2.1 --- Subjects --- p.124 / Chapter A.2.2 --- Equipment --- p.124 / Chapter A.2.3 --- Protocol --- p.125 / Chapter A.3 --- Methods --- p.126 / Chapter A.3.1 --- Algorithm --- p.126 / Chapter A.3.2 --- Data Analysis --- p.128 / Chapter A.4 --- Results --- p.129 / Chapter A.5 --- Discussion --- p.131 / Chapter A.6 --- Conclusion --- p.133 / Reference --- p.133 / Appendix B Derivation of the Moens-Korteweg Equation --- p.134 / Reference --- p.136

Gu Yingying. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2004. / Includes bibliographical references (leaves 155-164). / Abstracts in English and Chinese. / Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- IPFM Model --- p.1 / Chapter 1.1.1 --- Description of IPFM Model --- p.1 / Chapter 1.1.2 --- Background of IPFM Related Modeling --- p.3 / Chapter 1.2 --- Windkessel Model --- p.8 / Chapter 1.2.1 --- Background of the Windkessel Model --- p.8 / Chapter 1.2.2 --- Windkessel Related Modeling --- p.13 / Chapter 1.3 --- Photoplethysmogram (PPG) --- p.14 / Chapter 1.3.1 --- Principle of PPG --- p.14 / Chapter 1.3.2 --- Characteristics of PPG Signal --- p.16 / Chapter 1.4 --- A Study on the Beat-to-Beat BPV --- p.18 / Chapter 1.5 --- Main Purposes of the Study --- p.19 / Chapter 1.6 --- Organization of the Thesis --- p.20 / Chapter 2 --- Spectral Analysis on the IPFM Process --- p.22 / Chapter 2.1 --- Introduction --- p.22 / Chapter 2.2 --- A Theoretical Study on the Neural Firing Rate Function --- p.23 / Chapter 2.2.1 --- Mathematical Derivation of the Neural Firing Rate --- p.23 / Chapter 2.2.2 --- Spectral Analysis of the IPFM Process --- p.27 / Chapter 2.2.3 --- Reconstruction of Neural Firing Rate through LPF --- p.30 / Chapter 2.3 --- Effects of Neural Dynamics --- p.33 / Chapter 2.4 --- Discussion & Conclusion --- p.35 / Chapter 3 --- A New Model for the Generation of PPG --- p.37 / Chapter 3.1 --- Introduction --- p.37 / Chapter 3.2 --- Principles of PPG --- p.38 / Chapter 3.2.1 --- Relationship between Pressure and Flow --- p.38 / Chapter 3.2.2 --- Peripheral Pressure and Flow Curves --- p.41 / Chapter 3.2.3 --- Generation of PPG signal --- p.43 / Chapter 3.3 --- Model Description --- p.44 / Chapter 3.3.1 --- IPFM model --- p.45 / Chapter 3.3.2 --- Windkessel model --- p.46 / Chapter 3.3.3 --- New Model for the Generation of PPG --- p.49 / Chapter 3.4 --- Simulation --- p.51 / Chapter 3.4.1 --- Generation of ECG --- p.51 / Chapter 3.4.2 --- Generation of PPG --- p.57 / Chapter 3.4.3 --- Effects of the Modulation Depth on the Output --- p.65 / Chapter 3.4.4 --- Effects of Mean Autonomic Tone on HRV --- p.72 / Chapter 3.5 --- Discussion & Conclusion --- p.75 / Chapter 4 --- A Correlation Study on the Beat-to-Beat Features of Photoplethysmographic Signals --- p.80 / Chapter 4.1 --- Introduction --- p.80 / Chapter 4.2 --- Methodology --- p.81 / Chapter 4.2.1 --- Experimental Conditions --- p.81 / Chapter 4.2.2 --- Definition of the Parameters --- p.82 / Chapter 4.3 --- Data Analysis --- p.85 / Chapter 4.3.1 --- At Normal Relaxed State --- p.85 / Chapter 4.3.2 --- At Different Levels of Contacting Force --- p.87 / Chapter 4.3.3 --- At Different Levels of Local Skin Finger Temperature --- p.90 / Chapter 4.3.4 --- At Dynamic State --- p.93 / Chapter 4.3.5 --- Repeatability Study --- p.95 / Chapter 4.3.6 --- Spectral Analysis --- p.96 / Chapter 4.4 --- Discussion --- p.98 / Chapter 5 --- The Estimation of the Beat-to-Beat Blood Pressure Variability --- p.103 / Chapter 5.1 --- Introduction --- p.103 / Chapter 5.2 --- BP Estimation using FY Interval --- p.104 / Chapter 5.2.1 --- Multi-Beat BP Estimation under Different Levels of Contacting Force --- p.104 / Chapter 5.2.2 --- Beat-to-Beat BP Estimation --- p.108 / Chapter 5.2.3 --- Repeatability Study --- p.112 / Chapter 5.3 --- A Study on the Beat-to-Beat BPV --- p.113 / Chapter 5.3.1 --- Background of the Beat-to-Beat BPV --- p.113 / Chapter 5.3.2 --- Analysis of the Beat-to-Beat BPV --- p.115 / Chapter 5.4 --- Improving the PPG Model with the Time-Varying BP --- p.120 / Chapter 5.4.1 --- Modification of the Model --- p.121 / Chapter 5.4.2 --- Simulation --- p.127 / Chapter 5.4.3 --- Application of the PPG Model --- p.132 / Chapter 5.5 --- Discussion & Conclusion --- p.134 / Chapter 6 --- A Novel Biometric Approach --- p.139 / Chapter 6.1 --- Introduction --- p.139 / Chapter 6.2 --- Human Verification by PPG Signal --- p.140 / Chapter 6.2.1 --- Experiment --- p.141 / Chapter 6.2.2 --- Feature Extraction --- p.142 / Chapter 6.2.3 --- Decision-making --- p.143 / Chapter 6.2.4 --- Results --- p.146 / Chapter 6.3 --- Discussion --- p.149 / Chapter 7 --- Conclusions --- p.151 / Chapter 7.1 --- Conclusions of Major Contributions --- p.151 / Chapter 7.2 --- Work to Be Done --- p.154

Teng Xiaofei. / "June 2004." / Thesis (Ph.D.)--Chinese University of Hong Kong, 2004. / Includes bibliographical references. / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web. / Abstracts in English and Chinese.

Consequently, this study aims to develop novel technologies that can measure BP non invasively and continuously without a cuff. The proposed method estimates BP using features including pulse transit time (PTT), which is defined as the time interval from R wave of electrocardiogram to onset of photoplethysmogram within the same heart cycle. / Despite the importance of controlling blood pressure (BP) to our health, BP remains inadequately managed worldwide. Due to global ageing and change of human lifestyles, the number of hypertensives is anticipated to continue rising from approximately 1 billion in 2000 to 1.56 billion by 2025. A stumbling block to BP management is high BP usually develops without obvious symptoms. As a result, many people are unaware of their condition until severe problems such as a stroke, a heart attack or kidney failure have occurred. In China, over 100 million people do not know they have developed hypertension and are living under a potential risk to their health. In addition to high BP, variations of BP are also independent indicators of morbidity and mortality of severe diseases. Yet, sudden changes in BP are difficult to be detected by state-of-the-art BP meters, which operate on principles that require an inflatable cuff to give only a snapshot of BP. / Lastly, since the technology required information from several sensors that are placed on different body parts of a person, development of body area network (BAN) has been an important research focus. The concluding chapter of this thesis presents a new concept in this area, namely the hybrid body area network (h-BAN). In particular, the use of biological channels (bio-channels) for intra-BAN communication and securing wireless intra-BAN communication is discussed. / Nevertheless, a major challenge of this approach is its requirement of a calibration procedure. One possible solution is to calibrate against a cuff-based device, but this is inconvenient particularly when calibration has to be refreshed from time to time. Therefore, a bio-model is proposed and developed for PTT along an artery where the hydrostatic component of BP varies. The model can be applied to calibrate the cuffless PTT-based approach and estimate BP by simple movements such as hand elevation. Several experiments were conducted to validate the assumptions of this model and the results were found to be promising. / The proposed PTT-based technology was evaluated on 85 subjects (aged 57+/-29 yrs., including 39 hypertensives) whilst they were at rest in a sitting posture. A total of 999 pairs of systolic BP (SBP) and diastolic BP (DBP) estimations were made with reference to conventional cuff-based devices (i.e. a mercury sphygmomanometer and an oscillometric device) over a period of 6.4 weeks. The results of the study show that reference and estimated BP differed by 0.4+/-9.3 mmHg and 0.8+/-5.8 mmHg for SBP and DBP respectively (AAMI required mean and SD to be less than 5 and 8 mmHg correspondingly). / The results of both studies show that the accuracy of the PTT-based technique is comparable to the cuff-based approaches. This technique is potentially useful to measure BP continuously. / To conclude, this work developed a non-invasive and cuffless approach for BP measurement and addressed several key issues of this approach, i.e. the analysis, calibration, and implementation of it. The work can help to realise new BP management schemes in mobile health (m-Health) and personalised healthcare systems, which are developed to cater for the needs of the increasing aging population world-wide and to prevent and control chronic diseases like hypertension. / To further the investigation, a second study which was to investigate in a clinical setting for post-operation condition, was carried out on 8 patients (aged 55+/-18 yrs.) using the averaged invasive arterial-line and cuff readings taken at intervals of 40.0+/-24.7 min. as reference. After calibrating the new approach on each individual, it can estimate SBP and DBP within 3.3+/-6.5 mmHg and 4.3+/-6.4 mmHg of the reference for the complete set of 89 estimations. / Poon, Chung Yan Carmen. / "December 2007." / Adviser: Yuon-Ting Zhang. / Source: Dissertation Abstracts International, Volume: 69-08, Section: B, page: 4888. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2007. / Includes bibliographical references (p. 91-103). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts in English and Chinese. / School code: 1307.