초음파 전달 감쇄 효과를 이용한 호흡측정기의 개발

초록

We have developed the ultrasonic spirometer which can be applied to pulmonary function test(PFT). Ultrasonic gas flow measurements are based on the determination of the time-of-flight (TOF) . This new system presented consists of ultrasonic sensors, transforming the natural, stochastic fluctuations of velocity into signal with a delay time T, and a real-time processing, extracting the delay time from the signals and calculating the average rate of flow of the gas. This method enables higher measurement accuracy than differential pressure method.