1264 results about "Velocity measurement" patented technology

A method and system for generating a patient specific anatomical heart model is disclosed. A sequence of volumetric image data, such as computed tomography (CT), echocardiography, or magnetic resonance (MR) image data of a patient's cardiac region is received. A multi-component patient specific 4D geometric model of the heart and aorta estimated from the sequence of volumetric cardiac imaging data. A patient specific 4D computational model based on one or more of personalized geometry, material properties, fluid boundary conditions, and flow velocity measurements in the 4D geometric model is generated. Patient specific material properties of the aortic wall are estimated using the 4D geometrical model and the 4D computational model. Fluid Structure Interaction (FSI) simulations are performed using the 4D computational model and estimated material properties of the aortic wall, and patient specific clinical parameters are extracted based on the FSI simulations. Disease progression modeling and risk stratification are performed based on the patient specific clinical parameters.

A system and method for measuring a parameter of a target in accordance with embodiments of the present invention includes transmitting at least one signal towards a target and receiving at least a portion of the transmitted signal back from the target. The measured parameter is one of distance velocity, or reflectivity. The transmitted signal is of the coherent burst waveform, and upon reception is processed with equivalent time sampling, AGC with minimal, if any, error, and a discrete Fourier transform.

A system for detecting and graphically displaying a contents of a fast-moving target object comprises: a radiation source, having a position such that at least a portion of radiation emitted from the radiation source passes through the fast-moving target object, the fast-moving target object having a variable velocity and acceleration while maintaining a substantially constant distance from the radiation source and being selected from the group consisting of: a vehicle, a cargo container and a railroad car; a velocity measuring device configured to measure the variable velocity of the fast-moving target object; a detector array comprising a plurality of photon detectors, having a position such that at least some of the at least a portion of the radiation passing through the target object is received thereby, the detector array having a variable count time according to the variable velocity and a grid unit size; a counter circuit coupled to the detector array for discretely counting a number of photons entering individual photon detectors, the counter circuit measuring a count rate according to a contents within the fast-moving target object; a high baud-rate interface coupled to the counter circuit for sending count information from the counter circuit at a rate fast enough to support real-time data transfer therethrough; and a processor coupled to the velocity measuring device and to the high-baud-rate interface, receiving count information from the high baud-rate interface and generating distortion-free image data in real time as a function of the count information and the variable velocity. A method for using the system is also disclosed.

An automatic timing measurement system that provides a measure of time of passage of a watercraft through a prescribed course. Algorithms based on inertial or other estimates augmented by GPS speed/position measurements are used to track position of a watercraft. Said position estimates are used to allow the locations of prescribed courses to be mapped and memorized. Algorithms are then used to allow the apparatus to automatically detect passage of a watercraft through mapped courses for the purpose of measuring and reporting time of passage of said watercraft past key points in said course, and for modifying the behavior of the speed control portion of the apparatus if necessary at certain points in the mapped course. A measure of accuracy of driver steering can be provided along with the ability to automatically steer the watercraft through the course if “steer-by-wire” mechanism is available. GPS speed control is augmented with a secondary velocity measurement device that measures speed over water resulting in an optional user selectable real-time compensation for water current. Furthermore, GPS is used as the key input to produce boat speed-based pull-up profiles.

A flow measurement device is disclosed, in which an accumulation of pollution substance onto a detection element is prevented, and which can measure a reverse flow similarly to a normal flow. On both ends of an outer wall 23 outer peripheral portion of a divided flow pipe 20 having a OMEGA-shape pipe passage, there are oppositely formed an inlet port 25 and an outlet port 26, which open in faces orthogonal to a flow direction of a main flow M that is a detection object. Within the divided flow pipe 20, by a curved partition 27, plural branch flow passages 28a, 28b mutually branching and joining in the divided flow pipe 20 are formed. Inside both end portions of the outer wall 23, undulation portions 32, 33 are formed so as to clog an inlet and an outlet of the outer peripheral side branch flow passage 28a and, by this, throttles are formed respectively in a flow passage between the inlet port 25 and the inlet of the branch flow passage 28a and a flow passage between the outlet port 26 and the outlet of the branch flow passage 28a. In a bottom portion of the outer wall 23 of the divided flow pipe 20, a detection element 31 is attached so as to be exposed to a flow in the outer peripheral side branch flow passage 28a and, against its detection face, a down flow DW further divided from a divided flow D obliquely impinges.

The invention discloses a method for positioning a micro seismic source or an acoustic emission source, which comprises the following steps of: placing a plurality of acoustic emission transducers nearby an object to be detected, and solving position coordinates of the micro seismic source or the acoustic emission source by using a nonlinear least square regression method, such as a simplex acceleration method or a Marquardt method or the like, according to the coordinate values and the time difference of the positions of the known transducers and according to a distance operational formula. The acoustic emission positioning method disclosed by the invention does not need to measure or preset acoustic velocity, can avoid the influence of acoustic velocity measurement on positioning, improves the positioning precision, and is convenient and practical in practical engineering application compared with a traditional method.

The invention relates to a rotating speed or speed measuring device and a detection method based on an accelerometer. The rotating speed or speed measuring device consists of a sensing detection part arranged on a carrier and a processing display part arranged on certain fixture at the far end, wherein the sensing detection part is connected with the processing display part through wireless communication. The rotating speed or speed measuring device uses the output signals of the accelerometer to extract the rotating centripetal acceleration of the carrier, obtains the rotating speed of the carrier according to the relations between the centripetal acceleration and the rotating radius and between the centripetal acceleration and the rotating speed, or detects the periodic signals output by the accelerometer in a time domain and a frequency domain to directly obtain the rotating cycle or frequency of the carrier to further obtain the rotating speed or the speed of the carrier. The rotating speed or speed measuring device has the advantages of low cost, simple structure, wide measuring range, high resolution ratio and the like; and simultaneously the device also has the characteristics of monitoring the state of the carrier remotely and providing the functions of prompting and alarming.

The invention relates to a system for evaluating the performance of a satellite navigation system. The system has a real-time evaluation mode and a playback evaluation mode and comprises a system positioning accuracy evaluation module, a system velocity measurement accuracy evaluation module, a system availability evaluation module, a system completeness evaluation module, a configuration holding capacity evaluation module and a multipath delay evaluation module, wherein the system positioning accuracy evaluation module evaluates system positioning accuracy by calculating a user equivalent range error and using a statistical method; the system velocity measurement accuracy evaluation module obtains a system velocity measurement accuracy conclusion by calculating a user pseudo-range error and using the statistical method; the system availability evaluation module respectively calculates the availability of the common mode and a wide area differential mode to obtain a system availability conclusion; the system completeness evaluation module obtains a system completeness conclusion by calculating the completeness of three parts, namely a satellite, a ground operational control system and a receiver; the configuration holding capacity evaluation module obtains a configuration holding capacity conclusion by counting constellation occupied time percentage; and the multipath delay evaluation module obtains a multipath delay conclusion by calculating the delay, amplitude and phase difference of a multipath signal relative to a direct signal. The system is easy to implement in engineering and can effectively evaluate the performance of the satellite navigation system.

The invention provides a millimeter wave frequency modulated continuous wave (FMCW) two-unit phased array distance and velocity measurement monolithic radar transceiver and belongs to the field of distance and velocity measurement radar transceivers. The millimeter wave FMCW two-unit phased array distance and velocity measurement monolithic radar transceiver is characterized by being formed by a FMCW transmitting module, a two-unit receiving module, a digital control module and a polarization generating module. The FMCW transmitting module is used for generating FMCW continuous-wave modulated signals, the continuous-wave modulated signals are sent out through an antenna after being amplified, the two-unit receiving module is used for processing signals reflected back from a target, the digital control module is used for controlling configurable amount in a system, sweep frequency cycle of FMCW modulation signals, sweep frequency bandwidth, signal transmitting power, gain of a receiving branch, bandwidth of a five-order Butterworth low-pass filter and phase shift value of a phase shifter can be configured, and the millimeter wave FMCW two-unit phased array distance and velocity measurement monolithic radar transceiver can be applied to detection of targets at close distance, far distance and different angles.

An acoustic logging apparatus comprises a drill collar conveyed on a drilling tubular in a borehole within a formation. At least one transmitter is disposed in the drill collar. The transmitter includes at least one magnetostrictive actuator cooperatively coupled by a flexure ring to a piston for converting a magnetostrictive actuator displacement into a related piston displacement for transmitting an acoustic signal in the formation.

A buoyant platform apparatus, such as a buoy, is described that comprises a laser radar (lidar) wind speed measurement device. The lidar is arranged to make wind velocity measurements at one or more remote probe volumes of known position relative to said platform. The wind speed measurement apparatus may further comprise motion sensing means that, in use, monitor motion of the platform allowing wind speed at an absolute position in space to be measured. Wind velocity data may also be compensated for platform movement.

The invention discloses a high-precision time interval measurement method based on phase modulation. Under the control of digital clock phase-shift, a path of high-frequency and low-jitter clock is transformed to N paths of clock signals having same frequency and fixed phase difference, and is taken as a counter reference clock; a counter is driven to count respectively in N paths of clock periods; two paths of clock signals, which have the smallest error, are extracted by utilizing the clock phase information; through the combination with the clock period and the counted values, the measurement valve of the time interval is worked out. Compared with the method using a single clock for counting, the high-precision time interval measurement method effectively reduces the measurement principle error, and can improve the measurement resolution ratio to 1/n of the reference clock. A measurement device is connected with a signal conditioning module, an FPGA module, a singlechip module and a display circuit module sequentially according to the signal processing order, and realizes high measurement precision, high measurement resolution ratio, high measurement speed, real time display, and stable and reliable work under a certain crystal oscillation frequency; and the integration in the FPGA is easy, and the expansion is flexible. The high-precision time interval measurement method can be used for measuring the speed in a high-speed motion.

The invention discloses a BD/DNS/IMU autonomous integrated navigation system and a method thereof. The system includes an airborne navigation computer, an IMU, a Doppler radar, a BD, an air data system, a data recorder, a monitoring system and an AHRS, wherein the IMU, the Doppler radar, the BD, the air data system, the data recorder, the monitoring system and the AHRS are connected with the airborne navigation computer. The method comprises the steps that a self-adapted Kalman filtering model is established by the adoption of a 'position + speed' matching mode, after pose matrix transformation is performed on the Doppler radar, differential operation is performed on velocity measurement information under the navigation system and velocity information calculated through inertial navigation solutions, and differential operation is performed on the position information outputted by the BD and the position information calculated through inertial navigation solutions; difference values obtained serve as observed quantity to perform Kalman filtering information fusion, and loop iteration is preformed on error variances of all branch systems in a state equation of a filtering estimating system; real-time closed-loop estimation is carried out, and all parametric variables in an inertial navigation system, the Doppler radar and the BD are amended to obtain final integrated navigation results after filtering correction. According to the BD/DNS/IMU autonomous integrated navigation system and the method thereof, long-endurance navigation can be carried out in an airborne and seamless mode in real time, navigation accuracy is high, and cost is low.

The invention provides a method and system for adjusting vehicle speed, beginning with a modulated laser pulse being emitted. A reference portion of the emitted modulated laser pulse is extracted, a reflected portion of the emitted modulated laser pulse is received, and the reflected portion is combined with the reference portion on a portion of an imaging array. A determination of a relative velocity is based on the combined reflected portion and reference portion.

A method is for determining a geometric vehicle inclination α of a motor vehicle, where an acceleration signal of at least one acceleration sensor is used and a speed gradient dv/dt is determined from a measured vehicle speed v, where a) in the case of a moving or standing vehicle, an acceleration value as is derived from a force acting on the acceleration sensor, b) a corrected acceleration value a_korr is determined as a function of the speed gradient dv/dt, and c) the current vehicle inclination α is directly deduced from the corrected acceleration value a_korr. In addition, a device for implementing a method to determine a geometric vehicle inclination α of a motor vehicle, the device includes a speed-measuring device and at least one acceleration sensor, a programmable and readable microcontroller being provided, with the aid of which the current vehicle inclination a may be calculated from the values of the speed-measuring device and the acceleration sensor at a vehicle speed v of the vehicle greater than or equal to zero, and directly transmitted to at least one control unit.

The invention relates to a carrier phase differential-based dual-antenna integrated positioning and orientation system and method. The system includes an antenna unit and a host unit, wherein the antenna unit is provided with two antennas which receive satellite navigation signals simultaneously, and the host unit comprises a main processing unit, an auxiliary processing unit, a differential data processing module and a differential orientation calculation module. The main processing unit and the auxiliary processing unit process signals received by corresponding antennas, and transmit synchronized original observed quantity to the differential data processing module after positioning is accomplished; the main processing unit and the auxiliary processing unit transmit respective original observed quantity data and positioning results to the differential orientating calculation module so that calculation can be performed; and finally, positioning, velocity measurement and orientation results of a whole unit can be obtained. With the dual-antenna integrated design adopted, the system of the invention has the advantages of small size, reliable use, high orientation precision, no time accumulated error and long stable working time; and differential calculation can be completed through a real-time calculation method, and the position and course results of a carrier can be obtained in a static state or dynamic state, and primary orientation time is short, and real-time performance is high.

The invention provides a mobile ultrasonic anemoclinograph and a method for measuring wind speed and direction, wherein the device comprises an ultrasonic wind speed and direction measuring unit, a mobile system carrier speed measuring unit and a system direction measuring unit; the wind speed and direction measuring unit comprises a base, a control circuit board, six measuring arms and six ultrasonic transmitting/receiving sensors; the measuring arms are connected to the base and in an included angle at 60 degrees in turn; each measuring arm is provided with an ultrasonic sensor; the speed and direction measuring unit of the system carrier comprises a speed sensor and a direction measuring component; simultaneously, the invention further provides a method for measuring the wind speed anddirection in actual environment under a mobile condition by ultrasonic, wherein the method comprises the steps of: measuring the wind speed and direction parameters under the mobile condition by the ultrasonic wind speed and direction measuring unit; combining the measured moving speed and direction parameters of the system carrier; and calculating the measured wind speed and direction parametersin actual environment of the system under a mobile condition.

A target tracking method uses sensor(s) producing target signals subject to positional and/or angular bias, which are updated with sensor bias estimates to produce updated target-representative signals. Time propagation produces time-updated target states and sensor positional and angular biases. The Jacobian of the state dynamics of a target model produces the state transition matrix for extended Kalman filtering. Target state vector and bias covariances of the sensor are time propagated. The Kalman measurement residual is computed to produce state corrections, which are added to the time updated filter states to thereby produce (i) target state updates and (ii) sensor positional and angular bias updates. The covariance of a state vector comprising target states and sensor positional and angular biases is propagated, producing measurement updated state covariance including (i) target position and velocity measurement covariance updates and (ii) the sensor positional and angular bias measurement covariance updates.

A device and method for determining the hydration and water content status of soft biological tissue is disclosed and includes a couple of ultrasonic transducers located at a known distance therebetween and held against the tissue of interest as well as an adjustable support system with angle measuring means necessary for evaluation of ultrasound velocity in this tissue. Based on the time-of-flight results of the ultrasound velocity measurement, the water content in the tested tissue is evaluated and the hydration status is determined. One embodiment of the invention is a wearable device attached to human calf measuring water content in muscle.