This paper proposed a T- Y tube model to simulate foe input impedance of arterial system. It improves and extends the asymmetric T-tube model which was firstproposed by O' Rourke[1] and developed laier by Liu et a...This paper proposed a T- Y tube model to simulate foe input impedance of arterial system. It improves and extends the asymmetric T-tube model which was firstproposed by O' Rourke[1] and developed laier by Liu et al.[2]. Based on foe asymmetricT-tube model. a T-Y tube model was proposed by adding branching tubes whichrepresem the iliac arteries.All the tubes are considered to be uniform,viscoelasticlongitudinally tethered cylindrical tubes.The upper tube terminates with a windkesselmodel, while the terminal arterioles of the lowr tube are expressed as a resistance.After proper eraluation of the parameters.the impedance of the arterial system iscalculated under normal physiological and hypertensive condition.The model canpredict impedance in good agreement with the experimentally obtained data no matterin normal physiological condition or in pathological condition In comparison with theasymmeric T-tube model,T- Y tube model is closer to anatomy structure of the human arlerial system and at the sametime much simpler than the extremely complex multiplebranching tube model Therefore it will be a valuable model in studying the influencesof various parameters on aorta impedance and ventricular-vascular coupling.展开更多
The energy migration interaction parameter CDD in high concentration Nd3+ doped YAG laser crystal was estimated using the Yokota-Tanimoto(Y-T) model and the spectral overlap model(SOM) of Kushida, respectively.Fi...The energy migration interaction parameter CDD in high concentration Nd3+ doped YAG laser crystal was estimated using the Yokota-Tanimoto(Y-T) model and the spectral overlap model(SOM) of Kushida, respectively.Firstly, the experimental luminescence decay curves of 4F3/2 state of Nd3+ ions in YAG laser crystal at room temperature for 2.0at.% and 3.0at.% Nd3+ concentrations reported by Mao were fitted successfully using the Y-T model, and the parameter CDD was obtained to be 1.50×10-39 cm6/s.Secondly, the parameter CDD was directly calculated using the spectral overlap model(SOM) of Kushida;CDD was calculated to be 2.73×10-39 cm6/s.By comparing the energy migration interaction parameter CDD with the energy transfer interaction parameter CDA(1.794×10-40 cm6/s), it was concluded that the energy migration rate between Nd3+ ions in YAG laser crystal was about 11 times larger than the energy transfer rate, and that energy migration played a very important role in high concentration Nd3+-doped YAG laser crystal.展开更多
文摘This paper proposed a T- Y tube model to simulate foe input impedance of arterial system. It improves and extends the asymmetric T-tube model which was firstproposed by O' Rourke[1] and developed laier by Liu et al.[2]. Based on foe asymmetricT-tube model. a T-Y tube model was proposed by adding branching tubes whichrepresem the iliac arteries.All the tubes are considered to be uniform,viscoelasticlongitudinally tethered cylindrical tubes.The upper tube terminates with a windkesselmodel, while the terminal arterioles of the lowr tube are expressed as a resistance.After proper eraluation of the parameters.the impedance of the arterial system iscalculated under normal physiological and hypertensive condition.The model canpredict impedance in good agreement with the experimentally obtained data no matterin normal physiological condition or in pathological condition In comparison with theasymmeric T-tube model,T- Y tube model is closer to anatomy structure of the human arlerial system and at the sametime much simpler than the extremely complex multiplebranching tube model Therefore it will be a valuable model in studying the influencesof various parameters on aorta impedance and ventricular-vascular coupling.
基金supported by the Scientific Project of Jiangxi Education Department of China ([2007]330)Scientific Project of Jiujiang University (05KJ01)
文摘The energy migration interaction parameter CDD in high concentration Nd3+ doped YAG laser crystal was estimated using the Yokota-Tanimoto(Y-T) model and the spectral overlap model(SOM) of Kushida, respectively.Firstly, the experimental luminescence decay curves of 4F3/2 state of Nd3+ ions in YAG laser crystal at room temperature for 2.0at.% and 3.0at.% Nd3+ concentrations reported by Mao were fitted successfully using the Y-T model, and the parameter CDD was obtained to be 1.50×10-39 cm6/s.Secondly, the parameter CDD was directly calculated using the spectral overlap model(SOM) of Kushida;CDD was calculated to be 2.73×10-39 cm6/s.By comparing the energy migration interaction parameter CDD with the energy transfer interaction parameter CDA(1.794×10-40 cm6/s), it was concluded that the energy migration rate between Nd3+ ions in YAG laser crystal was about 11 times larger than the energy transfer rate, and that energy migration played a very important role in high concentration Nd3+-doped YAG laser crystal.