Design of a High Precision Ultrasonic Gas Flowmeter

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...

Ultrasonic 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...

design and construction of a high precision tac

tac (time to amplitude convertor) is one of the most important time measurement instrumentswhich has great significance in many fields of science, especially radiation physics. a tac unit has beendesigned based on the start-stop analog method and nim (nuclear instrument modules) standards. afterdesigning the circuit, it was simulated by pspice software and constructed by discrete and integrated...

Ultrasonic Solution For High Pressure Gas Service

The wide-range ejector flowmeter: calibrated gas evacuation comprising both high and low gas flows.

The wide-range ejector flowmeter is an active scavenging system applying calibrated gas removal directly to the anaesthetic circuit. The evacuation rate can be adjusted on the flowmeter under visual control using the calibration scale ranging from 200 ml X min-1 to 151 X min-1. The accuracy of the calibration was tested on three ejector flowmeters at 12 different presettings. The percentage dev...