31 results about "Velocity waveform" patented technology

A method and apparatus for determining the mean arterial blood pressure (MAP) of a subject during tonometric conditions. In one embodiment, the apparatus comprises one or more pressure and ultrasound transducers placed over the radial artery of a human subject's wrist, the latter transmitting and receiving acoustic energy so as to permit the measurement of blood velocity during periods of variable compression of the artery. During compression, the ultrasound velocity waveforms are recorded and processed using time-frequency analysis. The time at which the mean time-frequency distribution is maximal corresponds to the time at which the transmural pressure equals zero, and the mean pressure read by the transducer equals the mean pressure within the artery. In another aspect of the invention, the ultrasound transducer is used to position the transducer over the artery such that the accuracy of the measurement is maximized. In yet another aspect of the invention, a wrist brace useful for measuring blood pressure using the aforementioned apparatus is disclosed. A method of continuously estimating systolic and diastolic pressure is also described.

The invention provides a peripheral arterial blood vessel elasticity evaluation system based on a double triangle blood flow model, and relates to the technical field of medical and health electronics. The present invention first collects peripheral arterial pulse waves, and removes noises such as power frequency interference and baseline drift from the pulse waves. The feature points were extracted from the filtered signal, and the blood flow velocity waveform was fitted using the double triangle blood flow model according to the position of the feature points, and the pulse waveform was decomposed based on the double triangle blood flow velocity waveform to obtain the forward wave and the backward wave. Finally, according to the extracted characteristic points of the forward wave and backward wave, the backward wave enhancement index RM and reflection index RI reflecting the elasticity of peripheral arterial vessels are calculated. The present invention accurately decomposes the peripheral arterial pulse wave according to the fitted blood flow waveform, calculates relevant parameters based on the decomposed result, integrates the characteristics of the forward wave and the backward wave, and realizes the evaluation of the vascular sclerosis degree of the peripheral artery and the function of the cardiovascular system Evaluation makes it easier to detect cardiovascular function.

The invention relates to a rapid fault diagnosis method for pump equipment. The rapid fault diagnosis method comprises the following steps that n groups of continuous reference acceleration waveform and speed waveform data are selected when the pump equipment operates normally, and an average value AbAvg of effective values of the n groups of reference acceleration waveforms and an average value VbAvg of effective values of n groups of reference speed waveforms are correspondingly calculated; the current acceleration waveform and speed waveform of the pump equipment are collected, a speed effective value VRms and an acceleration effective value ARms are calculated, and the running state of the pump equipment is judged; and the speed effective value VRms and / or the acceleration effective value Arms are / is analyzed and processed, and the fault reason of the pump equipment is judged. According to the scheme provided by the invention, the fault reason of the pump equipment can be conveniently and timely positioned according to the collected current data and the historical data, so that the accuracy of fault detection is improved, a worker can timely find and solve problems, and the non-planned shutdown loss caused by sudden faults of the pump equipment is reduced.