Phasic aortic flow velocity was recorded in two patients with pulsus alternans using a flow velocity probe connected to a Doppler ultrasonic flowmeter system. The variations in beat-to-beat peak velocity paralleled the variations in arterial and ventricular systolic pressures. This study provides direct evidence that stroke volume varies during this abnormal haemodynamic status. It is conceivab...

–The software system of ultrasonic ranging system in agricultural robot was designed. This ultrasonic ranging system has two most components including the transmitter and the receiver. The ultrasonic ranging method was concluded, and ultrasonic ranging system generally calculates distance using the time-of-flight method, and the sound velocity must adjust by temperature compensation method when...

Abstract Ultrasonic tomography, which is widely used in the study of fracturing process rocks, often exhibits low resolution due to insufficient ray coverage, particularly while evaluating three-dimensional (3D) fractures. To resolve this issue, we adopted sparseness regularisation tomography reconstruct ultrasonic velocity rocks. Both numerical and laboratory experiments demonstrate that with ...

This paper introduces research and development of a modern non-invasive device for determining flows velocity fields. is based on the ultrasonic method. The measured fluid flow surrounded by appropriate transmitters receivers, which communicate with each other. A physical principle this method consists in an interaction sound waves flow, generates certain delay transmission. found quantity thus...

During the last three years the Swedish Institute for Metals Research (SIMR) has done extensive work on applications of laser generated ultrasound (LUS). This paper reports results from several experiments mainly aimed at industrial on-line applications. LUS has been used to determine grain sizes in commercial low-carbon (LC) and stainless steels. The analysis method employs a scattering theory...