Results 191 to 200 of about 2,011,937 (232)

Wave intensity analysis of para-aortic counterpulsation

American Journal of Physiology-Heart and Circulatory Physiology, 2012
Wave intensity analysis (WIA) was used to delineate and maximize the efficacy of a newly developed para-aortic blood pump (PABP). The intra-aortic balloon pump (IABP) was employed as the comparison benchmark. Acute porcine experiments using eight pigs, randomly divided into IABP ( n = 4) and PABP ( n = 4) groups, were conducted to compare the ...
Pong-Jeu, Lu, Chi-Fu Jeffrey, Yang, Meng-Yu, Wu, Chun-Hao, Hung, Ming-Yao, Chan, Tzu-Cheng, Hsu   +5 more
openaire   +2 more sources

Wave Intensity Analysis of Left Ventricular Filling

Journal of Biomechanical Engineering, 2005
Wave intensity analysis (WIA) is a powerful technique to study pressure and flow velocity waves in the time domain in vascular networks. The method is based on the analysis of energy transported by the wave through computation of the wave intensity dI=dPdU, where dP and dU denote pressure and flow velocity changes per time interval, respectively.
L L, Lanoye, J A, Vierendeels, P, Segers, P R, Verdonck   +3 more
openaire   +2 more sources

Wave intensity analysis and the development of the reservoir–wave approach

Medical & Biological Engineering & Computing, 2009
The parameters of wave intensity analysis are calculated from incremental changes in pressure and velocity. While it is clear that forward- and backward-traveling waves induce incremental changes in pressure, not all incremental changes in pressure are due to waves; changes in pressure may also be due to changes in the volume of a compliant structure ...
John V, Tyberg, Justin E, Davies, Zhibin, Wang, William A, Whitelaw, Jacqueline A, Flewitt, Nigel G, Shrive, Darryl P, Francis, Alun D, Hughes, Kim H, Parker, Jiun-Jr, Wang   +9 more
openaire   +2 more sources

S‐wave splitting intensity analysis and inversion

Geophysical Prospecting, 2019
ABSTRACTAnalysing S‐wave splitting has become a routine step in processing multicomponent data. Typically, this analysis leads to determining the principal directions of a transversely isotropic medium with a horizontal symmetry axis, which is assumed to be responsible for azimuthal anisotropy, and to the time delays between the fast and slow S‐waves ...
Daniele Boiero, Claudio Bagaini
openaire   +1 more source

Wave-intensity analysis: a new approach to coronary hemodynamics

Journal of Applied Physiology, 2000
In 10 anesthetized dogs, we measured high-fidelity left circumflex coronary (PLCx), aortic (PAo), and left ventricular (PLV) pressures and left circumflex velocity ( U LCx; Doppler) and used wave-intensity analysis (WIA) to identify the determinants of PLCx and U LCx.
Y H, Sun, T J, Anderson, K H, Parker, J V, Tyberg   +3 more
openaire   +2 more sources

Wave intensity analysis of high frequency vibrations

Philosophical Transactions of the Royal Society of London. Series A: Physical and Engineering Sciences, 1994
In the statistical energy analysis (SEA) approach to high frequency dynamics it is assumed that the vibrational wavefield in each component of an engineering structure is diffuse. In some instances the directional filtering effects of structural joints can lead to highly non-diffuse wavefields, and in such cases sea will yield a very poor estimate of ...
openaire   +1 more source

Notice of Retraction: Wave intensity analysis in elastic tubes

2011 2nd International Conference on Artificial Intelligence, Management Science and Electronic Commerce (AIMSEC), 2011
Wave intensity analysis is a time method for studying waves in elastic tubes. Usually, the forward wave intensity is positive and backward wave intensity is always negative. The reflection coefficient RWI, which is defined as the magnitude ratio of reflected wave intensity and incident wave intensity, can be used to estimate the blocked extent. In this
null Xiangjiao Lian, null Zhigang Chen, null Ming Zhou, A.w. Khir, null Jiling Feng   +4 more
openaire   +1 more source

Wave-intensity analysis: a new approach to left ventricular filling dynamics

Heart and Vessels, 1997
In order to explore a new approach to the analysis of diastolic dysfunction, we adapted wave-intensity analysis (WIA), a time-domain analysis that provides information regarding both upstream and downstream events, to left ventricular (LV) filling. WIA considers the pressure and flow waves as summations of successive wavelets, characterised by the ...
J M, MacRae, Y H, Sun, D L, Isaac, G M, Dobson, C P, Cheng, W C, Little, K H, Parker, J V, Tyberg   +7 more
openaire   +2 more sources

Wave intensity analysis of left ventricular filling: application of windkessel theory

American Journal of Physiology-Heart and Circulatory Physiology, 2007
We extend our recently published windkessel-wave interpretation of vascular function to the wave intensity analysis (WIA) of left ventricular (LV) filling dynamics by separating the pressure changes due to the windkessel from those due to traveling waves. With the use of LV compliance, the change in pressure due solely to LV volume changes (windkessel
Jacqueline A, Flewitt, Tracy N, Hobson, Jiun, Wang, Clifton R, Johnston, Nigel G, Shrive, Israel, Belenkie, Kim H, Parker, John V, Tyberg   +7 more
openaire   +2 more sources

Assessing Single Ventricle Function in the Fontan Circulation using Wave Intensity Analysis

Pediatric Cardiology, 2021
John Valdovinos, Nicolas Eng, Matthew R Russell, S. Zahn, D. Levi   +4 more
semanticscholar   +1 more source