35 results about "Flow waveform" patented technology

A cardiovascular parameter such as cardiac output is estimated from a current pressure waveform data set without needing to directly measure blood flow or arterial compliance. The general shape of an input flow waveform over one beat-to-beat cycle is assumed (or computed), and then the parameters of a flow-to-pressure model, if not pre-determined, are determined using system identification techniques. In one embodiment, the parameters thus determined are used to estimate a current peripheral resistance, which is used not only to compute an estimate of the cardiovascular parameter, but also to adjust the shape of the input flow waveform assumed during at least one subsequent beat-to-beat cycle. Another embodiment does not require computation of the peripheral resistance and still another embodiment computes a flow estimate from an optimized identification of the parameters defining the assumed input flow waveform.

The invention relates to a man-machine asynchronous mechanical ventilation detection method based on a circulating neural network. The method comprises the following steps: a, collecting respiratory records during mechanical ventilation, and marking types of man-machine asynchrony by an expert; b, training and testing a multi-channel circulating neural network model on the basis of the marked respiratory records; c, detecting occurrence of various types of man-machine asynchrony by multi-model integration architecture. Characteristics of respiratory recording pressure waveforms and flow waveforms are fully extracted by adopting the multi-channel model structure, and after the characteristics are fused, the circulating neural network model is used for detecting occurrence of man-machine asynchrony. The occurrence of various types of man-machine asynchrony in the respiratory records can be simultaneously detected.

The present invention discloses a security big data analysis system and method based on a dynamic health degree model. The security big data analysis system comprises a big data acquisition device module, an independent data set archive module , a modeling and signature module, a daily security data analyzer module, a calculating module, an alarm module and a dynamic health degree model module; wherein the calculating module is used for obtaining corresponding data from the daily security data analyzer module and the modeling and signature module, and performing calculation through a virtual processor according to comparison of threshold values; the alarm module is used for judging whether to output an alarm according to a value calculated by the calculating module; and the independent data set archive module and the modeling and signature module are used for forming the dynamic health degree model module. The system and the method can accurately locate a small-probability key asset security event from big data flow waveforms, thereby improving security of data.

The invention discloses a thunder and lightning waveform on-line monitoring device of an high-speed railway overhead line system. The thunder and lightning waveform on-line monitoring device of the high-speed railway overhead line system comprises a power supply module, a remote control switch, an i-Core 2 core board, a colleting circuit, a thunder and lightning flow sensor, a time service module, a GPRS network module, a machine case shell, a limiting cushion block and the like. The thunder and lightning waveform on-line monitoring device is erected on a backflow wire of a monitored overhead line, when the overhead line system is struck by thunder, the thunder and lightning flow sensor obtains sensing voltage, the collecting circuit collects thunder and lightning flow waveform signals, collected information is sent to an upper computer through a wireless network, a lithium battery is charged through an electricity taking coil coupling electricity taking method, and an external power source is not needed. The thunder and lightning waveform on-line monitoring device of the high-speed railway overhead line system provides an original basis for mastering thunder and lightning waveforms, resisting thunder scientifically, analyzing thunder strike accidents and positioning thunder strike faults, and is simple in structure, convenient to install and maintain and reliable in work.

The present invention provides a system and method for estimating a blood flow waveform contour from a pressure signal. An arterial or ventricular pressure signal is acquired from a pressure sensor. Landmark points are identified on the pressure waveform that correspond to features of a flow waveform. In one embodiment, the landmark pressure waveform points correspond to the onset of flow, the peak flow, and the end of the systolic ejection phase. The landmark pressure waveform points define a contour that approximates the flow contour. Beat-by-beat flow contour estimation can be performed to allow computation of flow-related hemodynamic parameters such as stroke volume or cardiac output for use in patient monitoring and/or therapy management.

A gas flow waveform modulation variable polarity plasma welding method belongs to the technical field of welding methods. According to the invention, a regular plasma arch welding device is added with a gas flow waveform controller and a plasma gas control execution unit; the waveform output of the plasma gas flow can be realized during the welding process by controlling the plasma gas control execution unit; and the plasma gas flow is synchronously changed with the current during the welding process of the variable polarity plasma, so that the control of stability of the welding process and piercing can be realized. According to the invention, the stability of piercing and the welding process of the variable polarity plasma can be greatly improved and the stability is improved, so the quality of weld seam is conducive to be increased.

The present invention provides a dredged soil transport system including a pipe module wound with a coil applying an electromagnetic field to an internally flowing dredged soil and including a plurality of pipelines, a pump module configured to provide a transport pressure for transport of dredged soil to the pipe module, database stored with flow information on flow velocity and flow form in response to physical properties of liquefied unit, and a control module communicating with the pipe module, the pump module and the database wiredly and wirelessly and applying, to the coil, a current of waveform matching to a flow waveform of the dredged soil transported inside the pipeline, and a control method thereof.

The invention discloses an obstructive apnea judgment method of a non-invasive ventilator. The obstructive apnea judgment method comprises: acquiring the steady state flow respiration waveform characteristic data of a person to be detected; monitoring whether the person to be detected has apnea or not; when monitoring that the person to be detected has the apnea, driving a draught fan to simulate steady state rotation; acquiring simulated state flow waveform characteristic data and judging whether a difference value between the simulated state flow waveform characteristic data and the steady state flow respiration waveform characteristic data is larger than a pre-set value or not; if so, considering that the person has obstructive apnea. According to the obstructive apnea judgment method, flow change caused by an air leaking hole is very small, so that the judgment of the difference value can clearly distinguish whether the flow change is caused by air leaking or the flow change is caused by an open airway, and furthermore, the problem that the non-invasive ventilator difficultly judges whether the apnea is the obstructive apnea can be effectively solved.

The invention discloses a non-consumable electrode welding method with a gas-electricity pulse combined effect, and belongs to the field of welding methods. The method is characterized in that current in a non-consumable electrode welding power supply is changed in a pulse form; and the control of gas way gas flow required to be modulated is realized through combining a gas flow waveform controller and a gas flow control actuation unit with a current pulse waveform. As the combined control is performed for gas and electricity to achieve the gas-electricity pulse combined effect, the improvement of welding line formation and quality is realized. The welding method greatly enhances the gas and electricity matching degree, improves the non-consumable electrode welding process, and facilitates to improve the welding line formation and to enhance the welding line quality.

A pulsatile perfusion bioreactor for culturing one or more engineered blood vessels having a lumen and a wall is provided. The bioreactor includes a chamber for holding the engineered blood vessel and cell culture media; a mechanical property monitoring system for measuring axial tensile stress and strain, circumferential tensile stress and strain, and/or shear stress imparted on the vessel wall; and a pump system for delivering cell culture media through the vessel lumen, wherein the vessel is exposed to a composite pressure waveform and a composite flow waveform as the media is delivered there through. The pump system includes a steady flow and peristaltic pumps. Further, the composite pressure and flow waveforms each include a mean component, a fundamental frequency component, and a second harmonic frequency component. The bioreactor also includes a computer interface for monitoring and adjusting the composite waveforms to maintain a predetermined stress levels.

The invention discloses a sleep breath monitoring method. The sleep breath monitoring method comprises the following steps: step one, calculating average inhaling time and average exhaling time; steptwo, determining entering of a sleep apnea stage; step three, setting pulse parameters; step four, after sending out first pulse, detecting change of flow by a breathing machine; and step five, comparing flow waveform, recording blocking type apnea time and a current pulse numerical value, and finishing monitoring of blocking type apnea. Compared with the correlation technique, the sleep breath monitoring method is higher in accuracy of a monitoring result.

A control circuit for a sensorless implantable blood pump configured to determine mitral valve regurgitation includes a processing circuit configured to generate an estimated blood flow waveform from the sensorless implantable blood pump and to determine the mitral valve regurgitation if between an end diastole and an initial systole. If the measured amplitude of the estimated blood flow waveform does not include an inflection point, an alert is generated.

The embodiment of the invention discloses a respiratory frequency measuring method and device and HFNC equipment. The method comprises the steps: obtaining a corresponding flow and pressure amplitude-frequency curve graph according to collected flow and pressure data, obtaining a first maximum amplitude value and corresponding first initial respiratory rate data based on the flow amplitude-frequency curve graph, and obtaining a second maximum amplitude value and corresponding second initial respiratory frequency data through the pressure amplitude-frequency curve graph; calculating a first window value according to first initial respiratory frequency, calculating a second window value according to second initial respiratory frequency, and searching an actual flow peak-to-peak value set in a flow waveform curve graph generated by flow data by a window method; and according to the actual pressure peak value set in a pressure waveform curve graph generated by the pressure data, obtaining actual respiratory frequency data. Therefore, the problem of loss or over-extraction of the peak-to-peak value in the process of searching the peak-to-peak value can be reduced, and accurate respiratory rate data can be obtained.