The ultrasonic flowmeter
نویسندگان
چکیده
منابع مشابه
The Development of CPLD-Based Ultrasonic Flowmeter
The measurement principle of the transit time difference method of the ultrasonic flowmeter is presented. The hardware structure and realization method are introduced. The software function and work mode are overviewed. In order to enhancing flowmeter's precision and stability a Xilinx CoolRunner CPLD and a Texas Instruments microcontroller from MSP430 family are applied in high precision timin...
متن کاملUltrasonic doppler flowmeter-guided occipital nerve block
BACKGROUND Greater occipital nerve block is used in the treatment of headaches and neuralgia in the occipital area. We evaluated the efficacy of ultrasonic doppler flowmeter-guided occipital nerve block in patients experiencing headache in the occipital region in a randomized, prospective, placebo-controlled study. METHODS Twenty-six patients, aged 18 to 70, with headache in the occipital reg...
متن کاملMeasurement of velocity in rotational flows using ultrasonic anemometry: the flowmeter
In this paper a previously developed theoretical model of the measurement process performed by a transittime ultrasonic anemometer is applied to a fluid flowing through a circular section pipe. This model considers the influence of the shift of the acoustic pulse trajectory from straight propagation due to the flow on the measured speed. The aim of this work is to estimate the errors induced in...
متن کاملCorrelation of common carotid flow volume measured by ultrasonic quantitative flowmeter with pathological findings.
To evaluate the possibility of quantitatively diagnosing carotid and cerebral atherosclerosis noninvasively, we measured common carotid flow volume in 60 sides (30 patients), using an ultrasonic quantitative flowmeter, and then compared these findings to the severity score of carotid and cerebral atherosclerosis as determined at autopsy. Stenosis decreased common carotid flow volume in the caro...
متن کاملIn vitro assessment of an ultrasonic flowmeter for use in ventilated infants.
An ultrasonic flowmeter could be advantageous over a differential pressure pneumotachograph having a constant error in varying conditions. The in vitro accuracy of ultrasonic tidal volume (VT) estimates for ventilated infants were evaluated. Flow linearity and frequency response were tested, as was the influence of humidity and oxygen content on the accuracy of VT estimates. The linearity was w...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: The Journal of Thoracic and Cardiovascular Surgery
سال: 1973
ISSN: 0022-5223
DOI: 10.1016/s0022-5223(19)40644-2