Ferris C D, Stinnett H O
Bioengineering Program, University of Wyoming, Laramie 82071-3295, USA.
Biomed Sci Instrum. 1995;31:65-70.
To assist in the identification of physical/physiological parameters obtained from in vivo rat aortic artery dynamic pressure data, the natural (mobility) mechanical circuit model was constructed. The direct electrical analog of the model thus obtained was then analyzed using SPICE. The experimental data were obtained using a Multifunction Pressure Generator (MPG), appropriate pressure probes, and a high-speed video camera. Two 486 computers were used for system control and data recording and computation. Transfer functions in rational form of the ratio of the MPG input pressure (Pi) to the intra-arterial pressure (Po) were then generated in the s-domain. The mechanical circuit described by these rational functions was then constructed and transformed into its equivalent electrical model for analysis. On this basis, physiological pressures are represented by electrical currents, and volume flow rates by electrical voltages. The results obtained through steady-state (Bode plot) and transient analysis of the model developed suggest a compartmental model that explains the experimental observations. The mobility model is an improvement over previous models in that the mass element is referred to a single frame of reference, which agrees with the physical property that mass is a one-terminal device.
为了帮助识别从体内大鼠主动脉动态压力数据中获得的物理/生理参数，构建了自然（流动性）机械电路模型。然后使用SPICE对由此获得的模型的直接电模拟进行分析。实验数据是使用多功能压力发生器（MPG）、合适的压力探头和高速摄像机获得的。两台486计算机用于系统控制、数据记录和计算。然后在s域中生成MPG输入压力（Pi）与动脉内压力（Po）之比的有理形式传递函数。然后构建由这些有理函数描述的机械电路，并将其转换为等效电模型进行分析。在此基础上，生理压力由电流表示，体积流量由电压表示。通过对所开发模型的稳态（波特图）和瞬态分析获得的结果表明了一个解释实验观察结果的隔室模型。流动性模型是对先前模型的改进，因为质量元件被参考到单个参考系，这与质量是单端器件的物理特性一致。
