31 results about "Cardiac ratio" patented technology

Catheterization of the heart is carried out by inserting a probe having electrodes into a heart of a living subject, recording a bipolar electrogram and a unipolar electrogram from one of the electrodes at a location in the heart, and defining a window of interest wherein a rate of change in a potential of the bipolar electrogram exceeds a predetermined value. An annotation is established in the unipolar electrogram, wherein the annotation denotes a maximum rate of change in a potential of the unipolar electrogram within the window of interest. A quality value is assigned to the annotation, and a 3-dimensional map is generated of a portion of the heart that includes the annotation and the quality value thereof.

Catheterization of the heart is carried out by inserting a probe having electrodes into a heart of a living subject, recording a bipolar electrogram and a unipolar electrogram from one of the electrodes at a location in the heart, and defining a window of interest wherein a rate of change in a potential of the bipolar electrogram exceeds a predetermined value. An annotation is established in the unipolar electrogram, wherein the annotation denotes a maximum rate of change in a potential of the unipolar electrogram within the window of interest. A quality value is assigned to the annotation, and a 3-dimensional map is generated of a portion of the heart that includes the annotation and the quality value thereof.

A satellite constellation optimized for stationkeeping fuel consumption is provided. The satellite constellation includes a plurality of satellites, each satellite having a corresponding inclined elliptical orbit, each orbit having an initial right ascension of ascending node (“RAAN”) value, a RAAN drift rate, a semi-major axis, an eccentricity, an argument of perigee and an inclination. Each satellite has a fuel consumption value required to maintain the RAAN drift rate, the semi-major axis, the eccentricity, the argument of perigee and the inclination of the corresponding orbit. The initial RAAN value and the RAAN drift rate for each orbit correspond to a minimized fuel consumption value for the satellite having the highest fuel consumption value. The initial RAAN value and RAAN drift rate may be determined by calculating, for each possible data combination of an initial RAAN value for each orbit and a RAAN drift rate for the constellation, a fuel consumption value for each satellite in the constellation, and selecting, from the fuel consumption values thus determined, the data combination corresponding to a lowest fuel consumption for a highest fuel-consuming satellite.

The invention discloses a ventricular ectopic beat detection method based on a 1D (Dimension) convolutional neural network. As the convolutional neural network is generally applied to the aspect of two-dimensional image processing and an electrocardiosignal belongs to a one-dimensional time sequence, the invention designs a one-dimensional convolutional neural network used for detecting ventricular ectopic beats specific to the characteristics of the electrocardiosignal; meanwhile, the invention gives specific partition parameters on the electrocardiosignal specific to the characteristics of the electrocardiosignal, and a series of single cardiac beat data obtained by partitioning a cardiac arrhythmias database is input a specially designed one-dimensional convolutional neural network to be trained. Compared with the past method, the ventricular ectopic beat detection method disclosed by the invention has stronger robustness and higher detection precision.

The invention relates to a method for acquiring fetal heart sound signal envelope. The method comprises the following steps that a fetal heart sound signal is collected, and intervention processing is conducted on the signal; a template signal is acquired, matching filtering is conducted on the fetal heart sound signal after preprocessing by utilizing the template signal, so that a signal-to-noise-ratio wave shape is acquired; non-linear peak enhancement is conducted on the fetal heart sound signal after matching filtering according to slope variation of the signal within two adjacent moments, and the envelope of the fetal heart sound signal after the matching filtering is further acquired. The invention further relates to a device for achieving the method. The method and device for acquiring the fetal heart sound signal envelope has the following advantages of being strong in anti-interference capacity and capable of enabling periodicity of the signal to be more obvious, so that calculation of the following fetal heart rate is facilitated.

An X-ray computed tomography apparatus includes an X-ray source, a high voltage generating unit, an X-ray detector detecting X-rays transmitted through a subject to generate projection data, a storage unit storing the projection data in association with electrocardiographic data of the subject, a setting unit setting a specific cardiac phase in accordance with an operator's instruction, a reconstruction unit reconstructing a tomogram based on projection data sets acquired in specific periods centered on the specific cardiac phase throughout cardiac cycles, a period extending unit extending the specific period on the basis of a heart rate fluctuation range of the subject, and a control unit controlling the high voltage generating unit to generate a relatively high dose of X-rays in the extended specific period and generate a relatively low dose of X-rays in a period other than the extended specific period.

System (10) for extracting a fetal heart rate from at least one maternal signal using a computer processor(26). The system includes sensors(12-18)attached to a patient to receive abdominal ECG signals and a recorder and digitizer(20)to record and digitize each at least one maternal signal in a maternal signal buffer(22A-22D). The system further includes a peak detector(40)to identify candidate peaks in the maternal signal buffer. The signal stacker(42)of the system stacks the divides at least one maternal signal buffer into a plurality of snippets, each snippet including one candidate peak and a spatial filter(44)to identify and attenuate a maternal QRS signal in the plurality of snippets of the maternal signal buffer, the spatial filter including at least one of principal component analysis and orthogonal projection, to produce a raw fetal ECG signal which is stored in a raw fetal ECG buffer. The system further includes a fetal QRS identifier(46)for identifying peaks in the raw fetal ECG buffer by at least one of principal component analysis and a peak-detector followed by rule based fQRS extraction and a merger(48)to calculate and merge the fetal heart rate from the identified peaks.

The invention discloses a heart-rate estimation method and device based on fusion of electrocardiogram signals and pulse signals. The heart-rate estimation method includes the steps that heart rate estimation is carried out based on the electrocardiogram signals and the pulse signals respectively; the electrocardiogram signals and the pulse signals are subjected to signal quality evaluation respectively, and the signal quality index of the electrocardiogram signals and the signal quality index of the pulse signals are obtained; based on the two signal quality indexes, the two estimated heart rate values are subjected to kalman filtering processing; the two estimated heart rate values subjected to kalman filtering processing are subjected to weight fusion. By means of the heart-rate estimation method, the accuracy of heart-rate estimation can be effectively increased, and a reference is provided for clinical caring.

The invention discloses a heart rate monitoring method. In a vehicle, a driver and a passenger each wear a bracelet connected with a vehicle control system. The heart rate monitoring method comprises the steps that during vehicle running, the bracelet monitors the heart rate of the wearers and acquires the heart rate information of the wearers; the heart rate information is judged through the preset algorithm; and when the heart rate of the bracelet wearers is judged to be abnormal, the heart rate abnormal information is generated and sent to the vehicle control system, so that the vehicle running speed is decreased through the vehicle control system according to the heart rate abnormal information. The invention further discloses a heart rate monitoring device and a heart rate monitoring system. According to the heart rate monitoring method, the heart rate monitoring device and the heart rate monitoring system, in the vehicle, when the heart rate of the driver and the heart rate of the passenger are too high, the vehicle is decelerated so as to provide a comfortable driving environment for the driver and the passenger.

The invention provides an arterial fibrillation detecting method based on the single lead electrocardiosignal time-frequency characteristic, and belongs to the crossing field of information processingtechnologies and medical treatment and health. A distinctive characteristic of the arterial fibrillation detecting method is that for a high-noise singe lead electrocardiosignal, the Pearson correlation coefficient is utilized to carry out simple clustering on all heartbeat waveforms in the same signal, and then noise disturbance of the heartbeat waveforms is eliminated by utilizing the average method; and the representative heartbeat waveform of the signal is found out, and then the time-frequency characteristic of the representative heartbeat waveform is extracted based on the Matching Pursuits algorithm and then is used for classifying the whole electrocardiosignal. In addition, the characteristic of the RR interval is further integrated (the heart rate variability characteristic and the time-frequency characteristic of the heartbeat waveform are combined), and thus the features of a method based on atrial activities and a method based on ventricular response are both achieved, andthe detecting method has high accuracy and good robustness.

A position-detecting device includes a body pressure distribution sensor including a plurality of pressure sensors that outputs pressure signals corresponding to pressure values respectively and are arranged in a matrix pattern, a specific pattern storage unit storing a range that pressure sensors can occupy and a condition of pressure values relating to the pressure sensors within the range as a specific pattern by sleeping posture and body part of a sleeper, a scanning unit applying the specific pattern to body pressure distribution information, which is a set of the pressure values, from a scan starting position to an adjacent position in sequence and to determine whether the condition is satisfied, and a body part position determining unit determining the position of the body part in the sleeping posture corresponding to the position of the specific pattern in the body pressure distribution information when the condition is satisfied.

The invention relates to a cascaded LMS adaptive filtering PPG signal heart rate extraction method, comprising the following steps: filtering an original PPG signal through a band pass filter to remove out-of-band noise outside a normal range of a human heart rate value, to obtain a pre-processed signal D; when a heart rate sensor collects a signal, synchronously acquiring XYZ triaxial acceleration data by using a three-axis acceleration sensor, respectively constructing reference signals of an LMS adaptive filter by using the XYZ triaxial acceleration data, cascading into a three-channel cascaded LMS adaptive filter, wherein the pre-processed signal is used as an input of the filter to obtain filter response Y; calculating a PPG heart rate value by using a spectral peak tracing heart ratealgorithm, and optimizing by a three-point moving average algorithm and a limit formula to obtain a heart rate value corresponding to the PPG signal. The method can extract a heart rate of the PPG signal against motion artifacts and improve the calculation accuracy of the heart rate value of the PPG signal.

A heart-rate monitoring system for a monitoring subject for increasing performance improvement efficiency by the monitoring subject includes a heart-rate monitoring device having a sensor. The sensor is not in direct physical contact with the monitoring subject. The sensor provides sensing data; the heart-rate monitoring device calculates, from the sensing data, monitoring data relative to heart rate variability of the monitoring subject. The system includes an application server processing the monitoring data to calculate processed data and a user device for displaying the processed data in a format that increases the performance improvement efficiency by the monitoring subject.

The invention relates to the technical field of blood oxygen measurement, in particular to a dynamic heart rate and blood oxygen measuring method based on a Pearson's correlation coefficient. The method includes the steps of collecting signal data, preprocessing PPG data and triaxial accelerated speed data, calculating a curve indicating the changes of the Pearson's correlation coefficient along with rx, calculating the maximum wave crest and the minimum wave trough of the curve, calculating oxyhemoglobin saturation according to ra corresponding to the maximum wave crest and calculating the heart rate according to rv corresponding to the minimum wave through. The dynamic heart rate and blood oxygen measuring method based on the Pearson's correlation coefficient can achieve measurement of the oxyhemoglobin saturation under a movement state, overcome the defects of a high or inaccurate measurement value of the oxyhemoglobin saturation under the movement state, achieve accurate measurement of the dynamic heart rate and the oxyhemoglobin saturation under the movement state, and have a significant meaning in promotion of research and application development of blood oxygen health of the human body.

The invention discloses a fetal heart rate curve correction method. The fetal heart rate curve correction method is characterized by comprising the steps that the abnormal time period of a fetal heart rate curve is selected; fetal heart sounds during the time period are replayed; a fetal heart rate curve segment during the time period is corrected; an editable interface of the fetal heart rate curve segment during the time period is provided, manually edited fetal hear rate data during the time period is received, large sample data is collected at the cloud, and optimization learning is conducted on a correcting algorithm of the fetal heart rate curve segment by means of a big data analysis method. According to the fetal hear rate correction method, the editable interface of the fetal heart rate curve segment during the time period is provided, and medical personnel are assisted in conducting rapid correction on the fetal heart rate curve segment during the time period. In the diagnostic process of a case, diagnosis results are recorded and stored in the cloud, in turn, back feeding and optimization are conducted on the fetal heart rate curve segment correction algorithm by means of the large sample data, and the fetal heart rate curve correction algorithm can be perfected more persistently and comprehensively.

In a processing section 4, allowable gain-value range defining unit 41 measures a gain value k corresponding to a level ratio between an MPP signal and an SPP signal generated by a tracking error signal generating circuit 3 to define an allowable range of the gain value, and eccentricity measuring unit 42 measures an eccentricity of an optical disk. If the eccentricity is determined to be greater than or equal to a predetermined value by eccentricity determining unit 43, gain-value defining unit 44 selects a minimum value of the gain value k to define the minimum value as a gain value k of an amplifier 37. On the other hand, if the eccentricity is determined to be less than the predetermined value, the gain-value defining unit 44 selects a central value of the gain value k to define the central value as the gain value k of the amplifier 37.

The invention discloses a heart rate monitoring method which comprises the following steps: monitoring the heart rate of a first terminal user by the first terminal so as to obtain the heart rate information of the first terminal user; judging the heart rate information of the first terminal user by a preset algorithm; and if the heart rate of the first terminal user is abnormal, generating corresponding prompt information and sending the corresponding prompt information to a second terminal to provide prompt according to the prompt information. The invention also discloses a heart rate monitoring device and a heart rate monitoring system. The abnormal heart rate of the first terminal user can be monitored in time by the first terminal and sent to the second terminal, so that a second terminal user can know that the heart rate of the first terminal user is abnormal in time.

The invention relates to a method and device for adjusting a fetal heart and uterine contraction monitoring curve alarm range. The method for adjusting the fetal heart and uterine contraction monitoring curve alarm range comprises the following steps of: setting a fetal heart rate alarm range; judging whether the set fetal heart rate alarm range is the same as a default fetal heart rate alarm range or not; judging whether the set fetal heart rate alarm range is within the set safe fetal heart rate range of a system; automatically adjusting the fetal heart rate alarm range; and displaying the fetal heart rate alarm range and printing a fetal heart rate curve. The method and device for adjusting the fetal heart and uterine contraction monitoring curve alarm range has the advantages that theneeds of monitoring the fetal heart rate of a fetus at different periods in different areas can be satisfied, the risk caused by misoperation of a doctor during fetus monitoring is avoided and the reliability and the safety of the product are improved.

The invention discloses a ventricular ectopic beat detection method based on a 1D (Dimension) convolutional neural network. As the convolutional neural network is generally applied to the aspect of two-dimensional image processing and an electrocardiosignal belongs to a one-dimensional time sequence, the invention designs a one-dimensional convolutional neural network used for detecting ventricular ectopic beats specific to the characteristics of the electrocardiosignal; meanwhile, the invention gives specific partition parameters on the electrocardiosignal specific to the characteristics of the electrocardiosignal, and a series of single cardiac beat data obtained by partitioning a cardiac arrhythmias database is input a specially designed one-dimensional convolutional neural network to be trained. Compared with the past method, the ventricular ectopic beat detection method disclosed by the invention has stronger robustness and higher detection precision.

The invention provides a bus safety guarantee monitoring system and method, and belongs to the technical field of bus safety. According to the system and method, a velocimeter, first and second cameras, a smoke detector, a heart rate sensor, a breathing sensor, a brake component, a steering part, a positioning module, a first controller, a second controller and a first communication module are included. When the real-time heart rate is greater than the preset heart rate or the real-time breathing frequency is greater than the preset breathing frequency, the second controller remotely controlsthe first controller via the first communication module, and further steering part is controlled to steer towards the preset direction and the brake component is controlled to carry out braking of a vehicle. Operation is simple, the efficiency is higher, and the safety performance is higher.

In a processing section 4, allowable gain-value range defining unit 41 measures a gain value k corresponding to a level ratio between an MPP signal and an SPP signal generated by a tracking error signal generating circuit 3 to define an allowable range of the gain value, and eccentricity measuring unit 42 measures an eccentricity of an optical disk. If the eccentricity is determined to be greater than or equal to a predetermined value by eccentricity determining unit 43, gain-value defining unit 44 selects a minimum value of the gain value k to define the minimum value as a gain value k of an amplifier 37. On the other hand, if the eccentricity is determined to be less than the predetermined value, the gain-value defining unit 44 selects a central value of the gain value k to define the central value as the gain value k of the amplifier 37.

The invention relates to a joint control method of position maintenance and angular momentum unloading of synchronous orbit electric propulsion, comprising: determining the position maintenance period Ts, the control period Tc and the orbit measurement time Tm; The total time; the orbit measurement time Tm is obtained by rounding up the time required for orbit measurement to an integer number of orbit periods; a position keeping period Ts should include an orbit measurement process Tm and several control periods Tc: before the start of each position keeping period Ts , to calculate the control quantities of orbital elements in each control period: inclination control quantity vector (Δix, Δiy), eccentricity control quantity vector (Δex, Δey) and longitude drift rate control quantity ΔD; determine the electric thruster ignition parameters for each control period , the ignition parameters include ignition duration and ignition position; before the start of each control cycle Tc, the rotation angle of the electric thruster is determined according to the ignition parameters of the electric thruster and the angular momentum unloading amount.

The invention provides a method for processing a fetal heart rate curve data and a device thereof. The method comprises: obtaining the fetal heart rate curve data during a monitoring period; determining the positions of the first effective fetal heart rate data and the last effective fetal heart rate data in the fetal heart rate curve data; removing the fetal heart rate data before the position ofthe first effective fetal heart rate data in the fetal heart rate curve data; and removing the fetal heart rate data after the position of the last valid fetal heart rate data. The method automatically cuts the first end or the rear end of the fetal heart rate curve, eliminates the operation for medical staff to manually label the data, improves the cleanliness of the fetal heart rate curve, reduces the difficulty for doctors to identify fetal heart rate curves, and improves the efficiency of medical staff.

Heart rate sensors including high-aspect-ratio photodetector elements are discussed herein. Such high-aspect-ratio photodetector elements may provide improved signal-strength-to-power-consumption performance for heart rate sensors incorporating such photodetector elements as compared with heart rate sensors incorporating, for example, square photodetector elements.

A method to provide electrical stimulation therapy to stabilize ventricular rate of a heart during episodes of atrial fibrillation. The stimulation therapy may be a plurality of stimulation pulses delivered to the AV node during the AV node refractory period following the sensing of an atrial event.

The invention is suitable for the technical field of medical signal processing, and provides a method and a device for outputting parameters of a fetal heart rate curve. The method comprises the following steps of according to an original signal collected by fetal heart monitoring equipment, generating the fetal heart rate curve; extracting the fetal heart rate curve within a specified period of time; measuring the wave peak / wave trough parameters of the fetal heart rate curve within the specified period of time; simultaneously outputting the fetal heart rate curve and the measured wave peak / wave trough parameters. The method has the advantage that the wave peaks / wave troughs in the fetal heart rate curve can be accurately identified, so the outputted fetal heart rate curve can visually and correctly display the fetal heart rate acceleration and deceleration conditions, and a medical staff can conveniently and accurately perform identification according to the outputted fetal heart rate curve, and the identifying accuracy is improved.

The invention discloses a baseline identification method for a fetal heart rate curve. A device for implementing the method comprises a signal input detecting module, a baseline identification extracting module, a baseline value parameter calculating module and a baseline value parameter output module. The method comprises the following steps: first, inputting fetal heart rate signals, performing pre-calculation, average optimization and interpolation smoothing in the baseline identification extracting module through pre-treatment and extraction of the effective signals, and calculating a baseline value; then, calculating the baseline proportion in a range and descriptive statistical parameters in a parameter calculating module; finally, outputting the calculating result in the baseline value parameter output module. The baseline value is calculated according to fetal heart rate data of long-term fetal heart rate monitoring and the definition of a fetal heart rate baseline, and has a relatively specific physiological significance; through combination of accelerating, decelerating and variance classifications, counts and duration proportions of the fetal heart rate, more comprehensive information can be obtained from the fetal heart rate signals; through application of the extracted baseline valve, the frequency domain of the fetal heart rate and related entropy information can also be obtained.

A method for determining an eccentricity of an optical disc is provided. The method includes predetermining a plurality of optical disc with known eccentric distances, respectively measuring a ratio of maximum and minimum amplitudes of a tracking error signal of the optical discs, establishing an eccentric distance ratio table or curve, measuring a ratio of maximum and minimum amplitudes of the tracking error signal for an optical disc under test, and comparing the measured ratio with the table or curve to promptly determine the eccentricity distance of the optical disc under test.

A method is provided for determining current eccentricity of a rotating rotor which is equipped with a phase marker scanned at constant speed of rotation up to 500 rpm by a sensor of a phase marker at the point of the phase marker, and outside of the phase marker by at least one sensor of relative rotor vibrations, while after digitizing the signals of the sensors, estimates current position of the phasor of the 1st harmonic component of signal of the sensor of relative rotor vibrations in the complex plane, which is subsequently compared to a reference position of the phasor of the 1st harmonic component, which has been determined in advance, whereas the variation vector of the phasors is an image of eccentricity of the rotor. Further, a method of diagnostics of eccentricity of a rotating rotor is based on this method for determining current eccentricity.