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Jun Tai Shi - One of the best experts on this subject based on the ideXlab platform.
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Research on a Computational Method for Reservoir Pressure of a Water-Drive Condensate Gas Reservoir
Petroleum Science and Technology, 2013Co-Authors: Bicheng Yan, Jun Tai ShiAbstract:Reservoir Pressure of condensate gas Reservoir is an indispensable parameter for calculation of gas reserves, gas well productivity evaluation, dynamic analysis, and evaluation of anticondensate. The water-drive condensate gas Reservoir is ranked among the most complex types during development. In the development process, Reservoir Pressure declines, condensate oil dropouts, and content of water vapor in condensate gas increases, while edge water invades continuously, thus accurate calculation and prediction of Reservoir Pressure is particularly difficult and important. Calculation of retrograde gas condensate influenced by porous media adsorption and capillary Pressure, and water vapor content in condensate gas tested under different Pressure, according to material balance principle, material balance equation of water-drive condensate gas Reservoir is established by consideration of absorption in porous media, capillary Pressure and water vapor as well, and finally Reservoir Pressure at any time during p...
Yan Bicheng - One of the best experts on this subject based on the ideXlab platform.
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A computational method for Reservoir Pressure of water-drive condensate gas Reservoir
Acta Petrologica Sinica, 2012Co-Authors: Yan BichengAbstract:Reservoir Pressure of condensate gas Reservoir is an indispensable parameter for calculation of gas reserves,evaluation of gas-well productivity,dynamic analysis and assessment of retrograde condensation.The development of water-drive condensate gas Reservoir is ranked among the most complex types of gas Reservoir development.During the process of development,an accurate calculation and prediction of Reservoir Pressure is particularly difficult but important because Reservoir Pressure declines ceaselessly,condensate oil drops out continuously with an increase of the water-vapor content in condensate gas,and the edge water invades constantly.We tested the water-vapor content in condensate gas under different Pressures by calculating the retrograde gas condensate,which is influenced by adsorption of porous media and capillary Pressure.According to material balance principles,a novel material-balance equation for water-drive condensate gas Reservoir was established in consideration of porous-medium absorption,capillary Pressure and water vapor as well,and finally Reservoir Pressure at any time during production could be computed by iteration.Application results show that the Reservoir Pressure calculated with this method gets much closer to actual Reservoir Pressure,which virtually reduce the workload in field testing.
Kevin S. Heffernan - One of the best experts on this subject based on the ideXlab platform.
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Sex Differences in Peripheral Augmentation Index and Arterial Reservoir Pressure during Upper Limb Postural Shifts
Physiology, 2014Co-Authors: Kevin S. Heffernan, Ari G. Kasprowicz, Brendan J. Tarzia, Justin E. Davies, Darren P. CaseyAbstract:We examined the peripheral hemodynamic response to passive arm postural changes in young men and women. Radial artery pulse waveforms were captured using applanation tonometry in 20 men (age 27 ± 2 yrs, BMI 25 ± 1 kg/m2) and 20 women (age 27 ± 2 yrs, BMI 23±1 kg/m2). Arm position was maintained at either heart level or supported 14 cm above/below heart level in a randomized fashion. Systolic augmentation index (sAIx) and diastolic augmentation index (dAIx) were used as estimates of Pressure from wave reflections arriving in systole and diastole, respectively. A novel Reservoir-wave separation technique was used to obtain arterial Reservoir Pressure (Pressure generated by arterial capacitance). Women showed a significant reduction in radial diastolic Pressure-time integral (DPTI) () and Reservoir Pressure (), with no change in peripheral sAIx () or dAIx () when moving the arm from below to above heart level. Conversely, men showed an attenuated change in radial DPTI () concomitant with significant increases in Reservoir Pressure (), sAIx (), and dAIx (). Gravity-mediated changes in regional hemodynamics produced by passive arm postural shifts are sex specific. Men demonstrate less change in regional diastolic Pressure concomitant with increased augmentation index and arterial Reservoir Pressure.
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Resistance exercise training reduces arterial Reservoir Pressure in older adults with prehypertension and hypertension
Hypertension Research, 2013Co-Authors: Kevin S. Heffernan, Justin E. Davies, James E. Sharman, Eun Sun Yoon, Yuan-ta Shih, Chen-huan Chen, Bo Fernhall, Sae Young JaeAbstract:We examined changes in central blood Pressure (BP) following resistance exercise training (RET) in men and women with prehypertension and never-treated hypertension. Both Windkessel theory and wave theory were used to provide a comprehensive examination of hemodynamic modulation with RET. Twenty-one participants (age 61±1 years , n =6 male; average systolic blood Pressure (SBP)/diastolic blood Pressure (DBP)=138/84 mm Hg) were randomized to either 12 weeks of RET ( n =11) or an inactive control group. Central BP and augmentation index (AIx) were derived from radial Pressure waveforms using tonometry and a generalized transfer function. A novel Reservoir-wave separation technique was used to derive excess wave Pressure (related to forward and backward traveling waves) and Reservoir Pressure (related to the capacitance/Windkessel properties of the arterial tree). Wave separation using traditional impedance analysis and aortic flow triangulation was also applied to derive forward wave Pressure (Pf) and backward wave Pressure (Pb). There was a group-by-time interaction ( P
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Resistance exercise training reduces arterial Reservoir Pressure in older adults with prehypertension and hypertension.
Hypertension Research, 2012Co-Authors: Kevin S. Heffernan, Justin E. Davies, James E. Sharman, Eun Sun Yoon, Yuan-ta Shih, Chen-huan Chen, Bo Fernhall, Sae Young JaeAbstract:We examined changes in central blood Pressure (BP) following resistance exercise training (RET) in men and women with prehypertension and never-treated hypertension. Both Windkessel theory and wave theory were used to provide a comprehensive examination of hemodynamic modulation with RET. Twenty-one participants (age 61±1 years, n=6 male; average systolic blood Pressure (SBP)/diastolic blood Pressure (DBP)=138/84 mm Hg) were randomized to either 12 weeks of RET (n=11) or an inactive control group. Central BP and augmentation index (AIx) were derived from radial Pressure waveforms using tonometry and a generalized transfer function. A novel Reservoir-wave separation technique was used to derive excess wave Pressure (related to forward and backward traveling waves) and Reservoir Pressure (related to the capacitance/Windkessel properties of the arterial tree). Wave separation using traditional impedance analysis and aortic flow triangulation was also applied to derive forward wave Pressure (Pf) and backward wave Pressure (Pb). There was a group-by-time interaction (P 0.05). RET may reduce central BP in older adults with hypertension and prehypertension by lowering Pf and Reservoir Pressure without affecting Pressure from wave reflections.
Justin E. Davies - One of the best experts on this subject based on the ideXlab platform.
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Reservoir Pressure analysis of aortic blood Pressure: an in-vivo study at five locations in humans.
Journal of Hypertension, 2017Co-Authors: Om Narayan, Justin E. Davies, Alun D. Hughes, Kim H. Parker, Ian T. Meredith, James D. CameronAbstract:Introduction:The development and propagation of the aortic blood Pressure wave remains poorly understood, despite its clear relevance to major organ blood flow and potential association with cardiovascular outcomes. The Reservoir Pressure model provides a unified description of the dual conduit and
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Aortic Reservoir Pressure Corresponds to Cyclic Changes in Aortic VolumeSignificance
Arteriosclerosis Thrombosis and Vascular Biology, 2014Co-Authors: Martin G. Schultz, Justin E. Davies, Ashutosh Hardikar, Simon Pitt, Michela Moraldo, Niti M. Dhutia, Alun D. Hughes, James E. SharmanAbstract:Objective— Aortic Reservoir Pressure indices independently predict cardiovascular events and mortality. Despite this, there has never been a study in humans to determine whether the theoretical principles of the mathematically derived aortic Reservoir Pressure (RPderived) and excess Pressure (XPderived) model have a real physiological basis. This study aimed to directly measure the aortic Reservoir (ARdirect; by cyclic change in aortic volume) and determine its relationship with RPderived, XPderived, and aortic blood Pressure (BP). Approach and Results— Ascending aortic BP and Doppler flow velocity were recorded via intra-arterial wire in 10 men (aged 62±12 years) during coronary artery bypass surgery. Simultaneous ascending aortic transesophageal echocardiography was used to measure ARdirect. Published mathematical formulae were used to determine RPderived and XPderived. ARdirect was strongly and linearly related to RPderived during systole ( r =0.988; P
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Sex Differences in Peripheral Augmentation Index and Arterial Reservoir Pressure during Upper Limb Postural Shifts
Physiology, 2014Co-Authors: Kevin S. Heffernan, Ari G. Kasprowicz, Brendan J. Tarzia, Justin E. Davies, Darren P. CaseyAbstract:We examined the peripheral hemodynamic response to passive arm postural changes in young men and women. Radial artery pulse waveforms were captured using applanation tonometry in 20 men (age 27 ± 2 yrs, BMI 25 ± 1 kg/m2) and 20 women (age 27 ± 2 yrs, BMI 23±1 kg/m2). Arm position was maintained at either heart level or supported 14 cm above/below heart level in a randomized fashion. Systolic augmentation index (sAIx) and diastolic augmentation index (dAIx) were used as estimates of Pressure from wave reflections arriving in systole and diastole, respectively. A novel Reservoir-wave separation technique was used to obtain arterial Reservoir Pressure (Pressure generated by arterial capacitance). Women showed a significant reduction in radial diastolic Pressure-time integral (DPTI) () and Reservoir Pressure (), with no change in peripheral sAIx () or dAIx () when moving the arm from below to above heart level. Conversely, men showed an attenuated change in radial DPTI () concomitant with significant increases in Reservoir Pressure (), sAIx (), and dAIx (). Gravity-mediated changes in regional hemodynamics produced by passive arm postural shifts are sex specific. Men demonstrate less change in regional diastolic Pressure concomitant with increased augmentation index and arterial Reservoir Pressure.
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Resistance exercise training reduces arterial Reservoir Pressure in older adults with prehypertension and hypertension
Hypertension Research, 2013Co-Authors: Kevin S. Heffernan, Justin E. Davies, James E. Sharman, Eun Sun Yoon, Yuan-ta Shih, Chen-huan Chen, Bo Fernhall, Sae Young JaeAbstract:We examined changes in central blood Pressure (BP) following resistance exercise training (RET) in men and women with prehypertension and never-treated hypertension. Both Windkessel theory and wave theory were used to provide a comprehensive examination of hemodynamic modulation with RET. Twenty-one participants (age 61±1 years , n =6 male; average systolic blood Pressure (SBP)/diastolic blood Pressure (DBP)=138/84 mm Hg) were randomized to either 12 weeks of RET ( n =11) or an inactive control group. Central BP and augmentation index (AIx) were derived from radial Pressure waveforms using tonometry and a generalized transfer function. A novel Reservoir-wave separation technique was used to derive excess wave Pressure (related to forward and backward traveling waves) and Reservoir Pressure (related to the capacitance/Windkessel properties of the arterial tree). Wave separation using traditional impedance analysis and aortic flow triangulation was also applied to derive forward wave Pressure (Pf) and backward wave Pressure (Pb). There was a group-by-time interaction ( P
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Resistance exercise training reduces arterial Reservoir Pressure in older adults with prehypertension and hypertension.
Hypertension Research, 2012Co-Authors: Kevin S. Heffernan, Justin E. Davies, James E. Sharman, Eun Sun Yoon, Yuan-ta Shih, Chen-huan Chen, Bo Fernhall, Sae Young JaeAbstract:We examined changes in central blood Pressure (BP) following resistance exercise training (RET) in men and women with prehypertension and never-treated hypertension. Both Windkessel theory and wave theory were used to provide a comprehensive examination of hemodynamic modulation with RET. Twenty-one participants (age 61±1 years, n=6 male; average systolic blood Pressure (SBP)/diastolic blood Pressure (DBP)=138/84 mm Hg) were randomized to either 12 weeks of RET (n=11) or an inactive control group. Central BP and augmentation index (AIx) were derived from radial Pressure waveforms using tonometry and a generalized transfer function. A novel Reservoir-wave separation technique was used to derive excess wave Pressure (related to forward and backward traveling waves) and Reservoir Pressure (related to the capacitance/Windkessel properties of the arterial tree). Wave separation using traditional impedance analysis and aortic flow triangulation was also applied to derive forward wave Pressure (Pf) and backward wave Pressure (Pb). There was a group-by-time interaction (P 0.05). RET may reduce central BP in older adults with hypertension and prehypertension by lowering Pf and Reservoir Pressure without affecting Pressure from wave reflections.
Bicheng Yan - One of the best experts on this subject based on the ideXlab platform.
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Research on a Computational Method for Reservoir Pressure of a Water-Drive Condensate Gas Reservoir
Petroleum Science and Technology, 2013Co-Authors: Bicheng Yan, Jun Tai ShiAbstract:Reservoir Pressure of condensate gas Reservoir is an indispensable parameter for calculation of gas reserves, gas well productivity evaluation, dynamic analysis, and evaluation of anticondensate. The water-drive condensate gas Reservoir is ranked among the most complex types during development. In the development process, Reservoir Pressure declines, condensate oil dropouts, and content of water vapor in condensate gas increases, while edge water invades continuously, thus accurate calculation and prediction of Reservoir Pressure is particularly difficult and important. Calculation of retrograde gas condensate influenced by porous media adsorption and capillary Pressure, and water vapor content in condensate gas tested under different Pressure, according to material balance principle, material balance equation of water-drive condensate gas Reservoir is established by consideration of absorption in porous media, capillary Pressure and water vapor as well, and finally Reservoir Pressure at any time during p...
