36 results about "Peak velocity" patented technology

A second stage external jet nozzle mixer (20) includes identically formed lobes which equal in number the lobes of the first stage internal mixer. The external mixer works with the internal mixer, and furthers the mixing of the jet engine internal bypass flow with the internal jet engine core flow. This mixing levels the disparate flow velocities attendant with the jet engine exhaust, reduces the peak velocities from the jet engine core and increases the lower bypass velocities of the jet engine internal bypass flow. The lobes include complex curvatures that greatly enhance mixing of the gases and ambient cooling air, and thereby reduce noise. At the lobe terminus, the lobe dimensional characteristics may be adjusted to thereby adjust the total terminus area to achieve a match to a jet engine to cause that jet engine to run at a determined RPM and noise level. Noise attenuation may also be adjusted by changing lobe dimensions. Prior existing second stage exhaust jet nozzle mixers may be retrofitted to allow alteration of their total terminus area by employing the disclosed device and method.

A system and method for measurement of flow parameters in a sewer pipe that may be partially or completely filled. Flow parameters may include flow velocity, flow volume, depth of flow and surcharge pressure. Measurements are taken from a sensor head installed on the inside of the pipe at the top of the pipe approximately the larger of at least 1 foot or 1 pipe diameter upstream of a pipe opening. Flow velocity may be measured by two different technologies. The technology employed depends on whether or not the pipe is full. If the pipe is not full then flow velocity may be measured, for example, using a wide beam, ultrasonic, diagonally downward looking Doppler signal that interacts with the surface of the flow. If the pipe is full, then flow velocity may be measured using, for example, an average velocity Doppler sensor, a peak velocity Doppler sensor or an ultrasonic velocity profiler.

Ultrasonically determining flow parameters of a fluid (12) flowing through a passage (14), using far-field analysis. Includes: (a) acquiring near-field amplitude and phase change values of ultrasound waves transmitted (30) into, propagating through, and scattered (32) by, the flowing fluid; (b) determining far-field scattering amplitude distribution, A(θ, Δf), as two-dimensional function of scattering angle, θ, and Doppler frequency shift, Δf, from the acquired near-field amplitude and phase change values; and (c) determining flow parameters (peak velocity, velocity distribution, flow rate) of the flowing fluid, from the scattering amplitude distribution. Implementable using ‘clamp-on’ techniques including ultrasound wave transmitter and ultrasound wave detector array, clamped on, in an oppositely facing configuration, to the passage, for transmitting and detecting ultrasound waves propagating perpendicular to net flow direction of the flowing fluid. Applicable to different fluids (liquid or/and gas) flowing through different passages (channels, conduits, or ducts) of different types and sizes of processes.

A method is described for recognizing fatigue, the method comprising an ascertaining step, a determining step, and a comparing step. In the ascertaining step a first saccade and at least one further saccade of an eye movement of a person are ascertained using a gaze direction signal that models the eye movement. In the determining step, a first data point representing a first amplitude of the first saccade and a first peak velocity of the first saccade, and at least one further data point representing a further amplitude of the further saccade and a further peak velocity of the further saccade, are determined using the gaze direction signal. In the comparing step, the first data point and at least the further data point are compared with a saccade model. The person is recognized as fatigued if the data points have a predetermined relationship to a confidence region of the saccade model.

The invention discloses a prediction method for peak particle vibration velocity of column charge blasting. On the basis of existing spherical charge blasting vibration theory and stress wave superposition principle, axial detonation velocity influence of charge blasting is considered; a column charge is decomposed into a short column charge with the axial length of d; blasting vibration characteristics of the short column charge are mainly obtained through an Heelan solution; a theoretical solution of blasting vibration of a long column charge is compared with a Sadaovsk formula; and a length influence factor of the charge is introduced in the Sadaovsk formula to calculate the peak particle vibration velocity of column charge blasting. According to the method, the influence of the charge length in column charge blasting on the peak particle vibration velocity is considered, an attenuation relationship of the peak velocity along with a horizontal distance is given out, and the prediction and control of column charge blasting vibration can be realized; and corresponding charge length capable of maximizing the peak particle velocity can be obtained through a calculation model, so that the column charge blasting design can be subjected to peak velocity safety evaluation.

A system improves accuracy of blood flow peak velocity measurements as well as the speed and precision of an MR data acquisition workflow. A system for blood flow velocity determination in MR imaging comprises an MR imaging system. The MR imaging system acquires a three dimensional (3D) MR imaging dataset of a patient anatomical volume of interest and a one dimensional (1D) MR imaging dataset within the volume of interest automatically aligned in response to 3D vector directional information. An image data processor derives the 3D vector directional information by, deriving velocity magnitude data using the acquired 3D MR imaging dataset, identifying maximum velocity data using the derived velocity magnitude data and transforming the identified maximum velocity data to provide the 3D vector directional information. A calculation processor uses the acquired 1D MR imaging dataset to calculate a blood flow velocity in a direction determined by the 3D vector directional information.

The invention discloses a blasting parameter optimization method capable of guaranteeing safety of above-ground structures. The blasting parameter optimization method comprises the steps that a blasting testing program is formulated; blasting is carried out according to the testing program, three sets of testing data of all measuring points in the vertical direction, horizontal radial direction and horizontal tangential direction are obtained, and the set of testing data which the maximum peak velocity arithmetic mean value corresponds to are taken as analyzing data; a v-f calculation model and a blasting vibration velocity model of a blasting zone are solved; the peak value vibration velocity and the main frequency in the initial blasting design program are solved; the peak value vibration velocity and the main frequency contrast with an existing blasting vibration safe and permitted standard point by point, the initial blasting design program corresponding to the peak value vibration velocity and the main frequency which do not conform a safety regulation for blasting is adjusted until the blast vibration safety allowance standard is met. The method is high in applicability, operation is simple, civil and economic disputes and construction delay caused by blasting vibration damage to the above-ground structures can be avoided, and the economical benefits of construction sides are greatly improved.

The invention provides a blasting vibration prediction method based on Spark gene expression optimization, and involves the field of machine learning. The data preprocessing technology is used for processing blasting data, and a sample data set is obtained; by calculating the incoordination rate of each condition attribute, condition attributes with the incoordination rate lower than a threshold value are deleted from an original data set, and then a new data set is generated to serve as an input data set; on each node, an improved gene expression method is used for function optimization, a blasting vibration effect prediction function can be obtained, and then the prediction value of the blasting vibration peak velocity is obtained. The method can better solve the training efficiency problem under the condition of mass data, the new-generation parallel computing technology is adopted, the genetic expression programming algorithm is improved for the global function optimization of theblasting data, the convergence speed can be largely improved, and the training efficiency is improved without affecting the training precision.

The invention discloses a velocity measurement signal processing method for a Doppler velocimeter, comprising the following steps of: (A) preprocessing a received velocity measurement signal by using a filter; (B) carrying out Fourier analysis on the frequency of the signal obtained in the step (A) to obtain a reference velocity; (C) respectively solving the sine and a plurality of peak frequencies of the reference velocity obtained in the step (B) to respectively obtain a sine velocity curve and a peak velocity curve; and (D) comparing the reference velocity obtained in the step (B) with the sine velocity curve and the peak velocity curve obtained in the step (C) to obtain a corrected velocity curve. Three solving methods including a frequency Fourier analysis method, a sine solving method and a multi-peak frequency solving method are used in the velocity measurement signal processing method, so that the signal processing method is suitable for all the speed ranges, and the problem that the current velocity measurement method is difficult in velocity measurement in a region with low velocity smaller than 1000m/s, and particularly a region with the velocity close to 100m/s, is solved.

A subsurface floating cluster of current energy converters is disclosed. A cluster consists of many nodes on a single mooring cable. Two converters, rotating in opposite direction, are connected as a pair. At least two pairs, four converters, are connected to each node. Each converter consists of a rotor with curved blades, a transmission, and an electrical generator. A computer on the mother ship, that tows the cluster, controls the rotating rate of every rotor in the cluster. Each node moves vertically or horizontally according to the rotation-rate-differential in each pair of rotors. Each node seeks and remains in peak velocity region, or at a predetermined water depth, to convert kinetic energy to electricity with an optimal efficiency. This invention has characteristics of simplicity in design, using artificial intelligence to achieve high efficiency in peak speed region of an ocean current, incremental capacity, and mobility.

An ultrasound system with a matrix array (500) probe (10) operable in the biplane mode is used to assess stenosis of a blood vessel by simultaneously displaying two color Doppler biplane images (60a, 60b) of the vessel, one a longitudinal cross-sectional view (60a) and the other a transverse cross-sectional view (60b). The two image planes intersect along a Doppler beam line (68) used for PW Doppler. A sample volume graphic (SV) is positioned over the blood vessel at the peak velocity location in one image, then positioned over the blood vessel at the peak velocity location in the other image. As the sample volume location is moved in one image, the plane and/or sample volume location of the other image is adjusted correspondingly. Spectral Doppler data (62) is then acquired and displayed from the sample volume location.

A bone resector tool (100) comprises an ultrasonic transducer (8), typically generating longitudinal mode vibrations at around 40 kHz, and having an elongate blade portion (2) mounted thereto. The transducer (8) and blade portion (2) are mounted to a rotatably- drivable converter element (3). Rotation of the converter element (3) produces reciprocal longitudinal motion of the transducer (8) and blade portion (2). A counterweight (5B) is also mounted to the converter element (3), moving exactly out of phase with the transducer (8) and blade portion (2), such that a centre of mass of the whole system is stationary, reducing vibration of the tool (100) in a user's hand. The peak velocity due to the ultrasonic vibrations of a distal tip (6A) of the blade portion (2) is up to seven times greater than its peak velocity due to the reciprocal longitudinal motion. This permits rapid, low-effort cutting of bone with easy removal of cut debris and minimal consequent necrosis.