556 results about "PULSE PRESSURE DECREASE" patented technology

An implant for bone replacement and attachment in an animal's body including, a structural portion having an outer porous surface, a ceramic material applied to the porous surface of the structural portion, characterised in that the thickness of the ceramic material as applied utilizing pulsed pressure MOCVD is such that at least some of the pores of the porous surface are not completely closed.

An apparatus and method for measuring exercise quantity through a film-type pressure sensor are provided. The apparatus for measuring exercise quantity through a film-type pressure sensor comprises a film-type pressure sensor to sense pulse pressure of a user's body, a main body to calculate and display a heart rate (HR) and calories consumed based on the HR, and a band that is coupled to the main body and to which the film-type pressure sensor is attached. The band contains a first band portion which is coupled to the main body and a second band portion which contains the film-type pressure sensor and is coupled to the first band portion. The second band portion contains at least one projection to enhance the detection of the pulse pressure of the user.

Provided herein are implantable systems, and methods for use therewith, for monitoring a patient's arterial blood pressure. Electrode(s) implanting within and / or on the patient's heart are used to obtain a cardiogenic impedance (CI) signal indicative of cardiac contractile activity. Additionally, a signal (e.g., PPG or IPG signal) indicative of changes in arterial blood volume remote from the patient's heart is obtained using a sensor or electrodes that are implanted remote from the patient's heart. One or more metrics indicative of pulse arrival time (PAT) are determined, where each metric can be determined by determining a time from one of the detected features of the CI signal to one of the detected features of the signal indicative of changes in arterial blood volume. Based on at least one of the metric(s) indicative of PAT, arterial blood pressure is estimated, which can include determining values indicative of systolic blood pressure, diastolic blood pressure, pulse pressure and / or mean arterial blood pressure, and / or changes in such values.

The apparatus and methods of the present invention provide a non-invasive measurement of blood pressure with a frequency that approximates a continuous measurement. Blood pressure measurement provides information that is both clinically and diagnostically significant. In accordance with an aspect of the present invention, a method for providing a non-invasive measurement of blood pressure, includes obtaining a first input signal and a second input signal indicative of occlusive measurements of systolic blood pressure and diastolic blood pressure, respectively; tracking a signal indicative of pulse pressure; continuously measuring a third signal indicative of mean blood pressure; and processing the signals to obtain a measurement indicative of systolic and diastolic blood pressure, wherein at least a portion of the measurement indicative of systolic and diastolic blood pressure is continuous. The second input signal indicative of diastolic blood pressure is analyzed to identify a maximum amplitude of the signal, the maximum amplitude being indicative of the diastolic blood pressure measurement.

An approach for improving the chances of survival of an individual who has received a trauma including, for example, hemorrhage or blunt injury, by providing more relevant information regarding the individual to first responders including at least one of heart rate variability index value, a baroreflex sensitivity value, and a pulse pressure. This information being used in at least one implementation to provide medical treatment to injured individuals including dispatching assistance and / or prioritizing in a triage situation increasing the speed at which these decisions can be made. In one exemplary embodiment, the heart rate variability index value is determined based on the relative power of the high frequencies versus the relative power of the low frequencies. In one exemplary embodiment, the pulse pressure is determined based on the difference between systolic pressure and diastolic pressure.

An apparatus for a heart assist device, comprising a processing unit for computing the blood flow rate from the arterial pressure curve and for predicting at every heartbeat the closing time of the heart valve from the curve of the blood flow rate. The processing unit is adapted to deliver a signal for controlling a heart assist device at a point in time, a period ahead in time of the closing time of the heart valve, wherein the mechanical properties of the said heart assist device are taken into account in determining the period. The apparatus adapts itself to changes in a patient's heart frequency and aortic pressure.

The invention relates to a radar moving target Radon-fractional Fourier transform (RFRFT) long-time phase-coherent accumulation detection method, and belongs to the technical field of radar signal processing and detection. The radar moving target Radon-fractional Fourier transform long-time phase-coherent accumulation detection method includes steps of 1), performing range demodulation and pulse pressure for radar echo to complete intra-pulse accumulation; 2), initializing parameters; 3), completing long-time inter-pulse phase-coherent accumulation by RFRFT compensation distance and Doppler frequency migration; 4), traversing all search parameters and creating a distance-RFRFT domain detection unit graph; 5), performing constant false alarm rate detection for the detection unit graph; and 6), estimating movement parameters of a target and outputting movement point traces. The radar moving target Radon-fractional Fourier transform long-time phase-coherent accumulation detection method has the advantages that amplitude information and phase information of the echo of the moving target are simultaneously utilized for long-time phase-coherent accumulation, the distance and the Doppler frequency migration in a long-time accumulation procedure are compensated, background clutter and noise are effectively suppressed, an accumulation gain is increased, dim moving targets in the heavy cluster can be detected, the movement point traces of the target can be acquired, and the method has popularization and application value.

An ultrasonic liquefaction endodontic system having a graspable hand piece having a flow passageway therethrough. An ultrasonic energy generator is secured to the hand piece. A flexible injection tube is dimensioned for insertion into a tooth root canal. A source of flushing fluid under pulsed pressure is connected to the hand piece by which fluid pressure pulses having ultrasonic energy superimposed thereon are forced into a root canal.

The invention relates to a method for extracting gas in low air permeability coal layer by pulse fracture anti-reflection, comprising the following steps: firstly using the blast-proof pulse-type coal layer high pressure water injector with adjustable frequency and pressure from the coal layer, high tunnel or low tunnel; using the pulse water effect generated by the periodical change of high pressure pulse water inside the drill hole of coal body, wherein the maximum pulse pressure is 35 MPa, the flow is about 300 L / min, and the pulse frequency is 0-1460 times / min; forcing the macroscopic fracture in the coal layer to be expanded and communicated; promoting the micro-pore fracture to be formed and extended; forming a new regeneration fracture net; providing a permeable channel of water inthe coal layer so as to achieve the effects of improving the mechanical property of the coal body, reducing the stress of the coal body in front of the working face and improving the discharge rate of the gas. Through the method, the pressure releasing range of the coal layer is enlarged, the whole pressure is adequately released, the radius of influence range of fracture can reach 10-40 m, and the air permeability of the coal body can be improved by 100-1000 times; and the method is simple, easy to operate and good in effect.

An apparatus and method are disclosed for boring into teeth to remove decaying tool matter using a high pressure jet of water. A system according to the invention may include a pressurized water source operably connected to an applicator used to target the water stream at the decayed portion of the tooth. The invention contemplates water streams utilizing single or multiple stream orifices, pure water or particle-entrained streams, and constant high pressure or pulsing pressure to accomplish removal of oral material, including enamel.

A Chinese-medicinal pulse state sensor, a pulse state tester with closed-loop control for testing the pulse pressure, and its test method are disclosed. Said pulse state sensor has a probe and two or more strain beams with both ends fixed to the surface of said probe and the semiconductor strain foil to form two or more attached sensors.

The invention relates to an experimental device and method for pulse hydrofracture transforming of a shale gas storing layer. The experimental device comprises a high pressure water pump, a fracturing fluid pond, a filtering device, a waterpower pulse generating device, a triaxial stress loading device, a pressure sensor, a sound emission device, a throttle valve, an overflow valve, a data collection recording system and a core test specimen. The device provided by the invention can simulate the operating environment of a shale sample under main operating parameter such as different pulse pressures and impulse frequencies on a certain confining pressure condition; moreover, the device can monitor a space-time developing rule of cracks and can test permeability change before and after fracture in real time; therefore, an experimental platform is provided for researching pulse hydrofracture of a shale gas storing layer. The experimental device provided by the invention has strong practicality, is easy to assemble, convenient to operate, is compact in structure, and can better imitate fracture damage and permeability change mechanism of a shale sample of the shale gas storing layer under the actions of static pressure and pulse hydrofracture.

Wrist-worn devices and related methods measure a pulse transit time non-invasively and calculate a blood pressure value using the pulse transit time. A wrist-worn device includes an accelerometer, a photo-plethysmogram (PPG) or a pulse pressure sensor, and a controller. The PPG or the pulse pressure sensor coupled to the wrist-worn device for detecting an arrival of a blood pressure pulse at the user's wrist. The controller is configured to process output signals from the accelerometer to detect when the blood pressure pulse is propagated from the left ventricle of the user's heart, process a signal from the PPG or the pulse pressure sensor to detect when the blood pressure pulse arrives at the wrist, calculate a pulse transit time (PTT) for propagation of the blood pressure pulse from the left ventricle to the wrist, and generate one or more blood pressure values for the user based on the PTT.

New systems and methods for remotely monitoring the activity, security, and health of an individual are provided. The monitoring system can be used to monitor both residence security and typical residential activity that is linked to the well being and health of an individual and can alert a third party when there is a digression from a predetermined set parameters. The monitoring system can incorporate a number of sensing elements including door opening and closing detection elements, passive infrared sensors, energy sensors for detecting the turning on and off of general household appliances, weighing scales, systolic blood pressure or pulse pressure measurement apparatus, bioelectrical impedance analysis measurement apparatus, breath analysis, and blood-based biological marker detection and quantification.

The present invention provides a method, system, and apparatus to monitor cardiovascular signals such as arterial blood pressure (ABP), pulse oximetry (POX), and intracranial pressure (ICP). The system can be used to calculate and monitor useful clinical information such as heart rate, respiratory rate, pulse pressure variation (PPV), harmonic phases, pulse morphology, and for artifact removal. The method uses a statistical state-space model of cardiovascular signals and a generalized Kalman filter (EKF) to simultaneously estimate and track the cardiovascular parameters of interest such as the cardiac fundamental frequency and higher harmonics, respiratory fundamental frequency and higher harmonics, cardiac component harmonic amplitudes and phases, respiratory component harmonic amplitudes and phases, and PPV.

A method and apparatus for determining a cardiovascular parameter including receiving an input signal corresponding to an arterial blood pressure measurement over an interval that covers at least one cardiac cycle, determining a propagation time of the input signal, determining at least one statistical moment of the input signal, and determining an estimate of the cardiovascular parameter using the propagation time and the at least one statistical moment.

The present invention provides an apparatus and methods for continuous intravascular measurement of whole blood concentration, blood pressure, and pulse pressure. The intravascular catheter incorporates a sensor to measure whole blood sound velocity, attenuation, backscatter amplitude, and blood flow velocity and also incorporates existing technologies for multiple physiologic measurements of whole blood. Pulse wave velocity and wave intensity are derived mathematically for purposes of estimating degree of local vascular tone.

The invention belongs to the field of radar signal processing, and discloses a missile-borne SAR sub-aperture forward squint high-order nonlinear chirp scaling imaging method. According to the method, missile-borne SAR forward squint high-order nonlinear chirp scaling imaging is achieved through sub-aperture data, and the method can be used for SAR imaging of airborne platforms or missile-borne platforms. The method mainly includes the steps of firstly, conducting distance pulse pressure and time domain walking correction on an echo signal; secondly, converting the signal into the two-dimensional frequency domain, conducting frequency domain migration correction and secondary compression, and compensating for the high order phase in the orientation direction; thirdly, leading high-order nonlinear chirp scaling disturbance factors into the orientation frequency domain, and correcting the space variability of the Doppler frequency modulation and the high-order terms in the orientation direction; fourthly, focusing an image on the orientation frequency domain through spectrum analysis. The method solves the problem of decoupling of distance orientation and the orientation focus depth problem caused by time domain walking correction, and the method can meet the requirements for different scenes and high resolution and can be used for the field of ground mapping and other fields.

Assemblies are provided comprising a stent and a sensor positioned on and / or in the stent. Within certain aspects the sensors are wireless sensors, and include for example one or more fluid pressure sensors, contact sensors, position sensors, accelerometers, pulse pressure sensors, blood volume sensors, blood flow sensors, blood chemistry sensors, blood metabolic sensors, mechanical stress sensors and / or temperature sensors. Within certain aspects these stents may be utilized to assist in stent placement, monitor stent function, identify complications of stent treatment, monitor physiologic parameters and / or medically image a body passageway, e.g., a vascular lumen.

Methods for fragmenting ions in an ion trap are described. These methods involve a) selecting parent ions for fragmentation; b) retaining the parent ions within the ion trap for a retention time interval, the ion trap having an operating pressure of less than about 1×10-4 Torr; c) providing a RF trapping voltage to the ion trap to provide a Mathieu stability parameter q at an excitement level during an excitement time interval within the retention time interval; d) providing a resonant excitation voltage to the ion trap during the excitement time interval to excite and fragment the parent ions; e) providing a non-steady-state pressure increase of at least 10% of the operating pressure within the ion trap by delivering a neutral gas into the ion trap for at least a portion of the retention time interval to raise the pressure in the ion trap to a varying first elevated-pressure in the range between about 6×10-5 Torr to about 5×10-4 Torr for a first elevated-pressure duration; and f within the retention time interval and after the excitement time interval, terminating the resonant excitation voltage and changing the RF trapping voltage applied to the ion trap to reduce the Mathieu stability parameter q to a hold level less than the excitement level to retain fragments of the parent ions within the ion trap. The excitation time interval and the first elevated-pressure duration substantially overlap in time.

The invention belongs to the radar technology field, discloses a high resolution spotlight SAR self-focusing imaging method based on two-dimensional self-focusing and mainly solves a problem that excellent focusing of a uniform imaging area can not be realized through a self-focusing algorithm in the prior art. The method comprises steps that an original echo signal of a target is received, after distance pulse pressure of the echo signal is carried out, crude envelope error and phase error compensation for the signal is carried out; distance direction FFT and azimuth solution linearity frequency modulation operation and two-dimensional interpolation operation are carried out; after distance direction IFFT of a result after two-dimensional interpolation is carried out, distance migration of a distance skipping unit is evaluated, and envelope error correction is accomplished; V non-superposed distance sub blocks are formed through uniform division along the distance direction, and a phase error of each sub block is evaluated; corresponding weights of distance units are respectively calculated, distance errors of the distance sub blocks are evaluated respectively, space-variant error evaluation is accomplished, azimuth direction IFFT of the data after correction is carried out, and thereby SAR images having the excellent focusing effect are acquired.

A variable valve timing control system of an internal combustion engine includes a hydraulically-operated phase converter disposed between a sprocket and a camshaft, and having a phase-advance hydraulic chamber and a phase-retard hydraulic chamber for changing an angular phase of the camshaft relative to the sprocket. An electric pump is provided to supply working fluid selectively to one of the hydraulic chambers via a directional control valve. Also provided is a check valve disposed in a discharge line of the pump for permitting flow in a direction that the working fluid flows from the pump to the directional control valve and preventing any flow in the opposite direction, so as to prevent a pulse pressure arising from alternating torque exerted on the camshaft from being transmitted from either one of the hydraulic chambers via the discharge line to a discharge port of the pump.

The invention provides a compressed sensing synthetic aperture radar (SAR) imaging method based on fractional order fourier transformation, and belongs to the technical field of microwave imaging. For a sparse target scene, a system emits a linear frequency modulation pulse signal; by adopting a method for projecting an echo signal to a low-dimension measurement matrix, measurement data which are much smaller than those required by a Nyquist sampling principle are acquired; due to the echo signal, after a reconstruction matrix is constructed by a simplified fractional order fourier transformation domain sparse mode and a data acquisition mode, a calculated distance pulse pressure result is optimized by a compressed sensing signal reconstruction method and is subjected to distance migration correction and direction pulse pressure to obtain a target scene imaging result. By the imaging method, the measurement data amount of a target scene with a sparse characteristic can be greatly reduced; and pressure on data storage and data transmission can be effectively relieved.

The invention discloses a body feeling network-based sleeveless driven pulse pressure measurement and automatic calibration device. The device comprises a body feeling network node for acquiring a heart pulsation related signal from the body surface of a user, a body feeling network node for measuring a transmission distance between the heart and a heart pulsation related signal acquisition point, a body feeling network node for measuring angle change of the heart pulsation related signal acquisition point relative to the position of the heart, and a control and calculation central pivot. The body feeling network nodes of the device are distributed on the body surface of the user, so the device is simple and convenient to mount, has no injury to the human body and does not need to inflate sleeve straps in the calibration and measurement processes; the device realizes the communication between the nodes and the control and calculation central pivot in a wireless mode, is convenient to carry, does not affect the daily life and can be continuously used for long time; and simultaneously, the device extracts multiple physiological parameters aiming at different individuals and different physiological states to automatically finish calibration, and has high estimation accuracy of blood pressure, comprehensive monitoring and broad application range.

The invention relates to a radar slightly-moving target detection method based on a Radon-linear canonical ambiguity function (RLCAF) and belongs to the technical field of radar signal processing and detection. The radar slightly-moving target detection method based on the RLCAF comprises the following steps that (1) demodulation and pulse pressure are conducted on a radar echo in the distance direction so that in-pulse accumulation can be completed; (2) the type of a target to be detected is predicted, and parameters are initialized; (3) the distance and Doppler migration are compensated through the RLCAF and signal energy of a slightly-moving target is accumulated; (4) the parameters are traversed and searched, an RLCAF domain detection unit figure is established, and constant false-alarm detection is conducted; (5) target moving parameters are estimated and moving trace points are output. According to the radar slightly-moving target detection method based on the RLCAF, the advantages of an ambiguity function and the advantages of linear canonical transformation are combined, non-uniform velocity translational motion target signals or turning target signals can be flexibly matched and accumulated in a clutter background, the signal-to-clutter ratio is improved, range migration can be compensated through the extraction of a target observation value in a distance-slow-time plane, phase-coherent accumulation for a long time is completed, the detection capacity of radar to the slightly-moving target is improved, and therefore the radar slightly-moving target detection method based on the RLCAF is wide in applicability.