210 results about "Particle velocity" patented technology

In one embodiment the invention comprises a particle velocity sensor that includes a housing with a geophone mounted in the housing. A fluid that substantially surrounds the geophone is included within the housing. The particle velocity sensor has an acoustic impedance within the range of about 750,000 Newton seconds per cubic meter (Ns / m<3>) to about 3,000,000 Newton seconds per cubic meter (Ns / m<3>). In another embodiment the invention comprises method of geophysical exploration in which a seismic signal is generated in a body of water and detected with a plurality of co-located particle velocity sensors and pressure gradient sensors positioned within a seismic cable. The output signal of either or both of the particle velocity sensors or the pressure gradient sensors is modified to substantially equalize the output signals from the particle velocity sensors and the pressure gradient sensors. The output signals from particle velocity sensors and pressure gradient sensors are then combined.

The invention discloses a method and a device for full-wave-shape inversion based on a time domain-step velocity-stress elastic wave equation, wherein the method includes: adopting an adjoint method based on the perturbation theory, and confirming the adjoint equation of the time domain-step velocity-stress elastic wave equation and a corresponding gradient expression, in regard to model parameters, of an objective functional; conforming a forward-propagating wave field according to the time domain-step velocity-stress elastic wave equation, and conforming an inverse time extrapolation adjoint wave field according to the adjoint equation; confirming the gradient, in regard to the model parameters, of the objective functional according to the forward-propagating wave field, the inverse time extrapolation adjoint wave field and the gradient expression; and using a gradient iterative algorithm to carry out multi-scale full-wave-shape inversion. According to the method for the full-wave-shape inversion, before transmitted in an inverse-time mode, a wave field residual error does not need pretreatment, the conversion problems of particle velocity and particle displacement do not need to be considered, and inversion calculation efficiency can be improved.

An acoustic resonance device is installed in a compartment of a vehicle so as to reduce a low-frequency sound pressure (or noise) dependent upon a natural vibration. Specifically, an acoustic resonance device is a panel / diaphragm resonator, a resonance pipe, or a Helmholtz resonator, the inner space of which communicates with the compartment via an opening. The acoustic resonance device is positioned in proximity to an antinode of sound pressure owing to a natural vibration occurring in a driver / passenger space inside the compartment. Alternatively, the acoustic resonance device increases a particle velocity at a specific natural frequency or decreases sound pressure at an excitation frequency which occurs due to an external condition of the vehicle. The acoustic resonance device can be installed in a roof, a seat, a pillar supporting the roof, or a door of a vehicle.

A fiber optic sensor system for pressure measurements where the design permits multiplexity on the input side of the system and the optical part of the system, which has a sensor Fabry-Perot interferometer and a read-out interferometer, is based on low coherence fiber-optic interferometry techniques. This permits a high dynamic range and low sensitivity to the wavelength fluctuation of the light source as well as to the optical intensity fluctuations. The system includes fiber tip based Fabry-Perot sensors, where each sensor includes a diaphragm as the transducer. A combined pressure gradient sensor, air particle velocity sensor, as well as acoustic intensity sensor is built based on the fiber tip based Fabry-Perot sensors.

The invention belongs to the field of motor optimization designs, and relates to a multi-objective hybrid particle swam optimization design method for a double-fed wind power generator. The method comprises the following steps of: (1) determining a constraint condition and a to-be-optimized design variable of the double-fed wind power generator, and establishing sub-objective function equations to form a multi-objective function; (2) constructing variable space by using the to-be-optimized design variable, and constructing non-dominated solution sets of population according to the quality of an objective value; (3) ordering the non-dominated solution sets according a Pareto domination mechanism, determining a population niche by taking a non-dominated solution as a core, establishing a particle speed updating mechanism and finally obtaining an optimal design scheme; manufacturing a mode machine according to the optimal design scheme, inspecting an actual operation index of a motor, and comparing the actual operation index with an index given by the design scheme; and if the actual operation index exceeds a requirement range of operation indexes, adjusting a performance design scheme. Due to the adoption of the motor optimization design method provided by the invention, overall economic benefit and wind energy utilization rate of a wind power generating system can be improved.

A modified high efficiency kinetic spray nozzle is disclosed. The modified nozzle has a rapid expansion rate in the diverging region relative to prior art nozzles, which enables one to achieve much higher particle velocities without an increase in the main gas temperature. Preferably, the expansion rate of the supersonic nozzle in a portion of the diverging region is at least 1 mm2 per millimeter, more preferably 2 mm2 per millimeter, more preferably 5 mm2 per mm, with a most preferable expansion rate being 10 mm2 per millimeter.

A method for applying a ceramic coating over a substantially smooth protective coating on a metal substrate is disclosed. The method includes the step of air plasma spraying (APS) particles of the ceramic coating at a pre-selected particle velocity of at least about 500 meters per second. The ceramic coating particles have an average particle size no greater than about 50 microns. An article is also described, including a metal substrate; and a substantially smooth protective coating over the substrate, having a roughness (Ra) less than about 200 micro-inches. An adherent ceramic coating is disposed on the substantially smooth protective coating.

The present invention discloses a multi-parameter multi-object chaotic particle swarm parameter optimization method. The method comprises the steps of (1) determining a target function and a parameter to be optimized, (2) initializing an algorithm, (3) calculating the target function corresponding to each individual in a population, (4) updating an individual history optimal solution, (5) updating a particle velocity and position, (6) updating a global optimal solution set, (7) updating a global optimal solution, and (8) carrying out result judgment. Compared with a common random initialization method and an existing chaotic logistic mapping particle swarm initialization method, according to the method of the invention, the performance of global optimization is improved and the stability is good, compared with a common multi-object weighted optimization method, the Pareto optimal solution technology is employed by the method, and the problem of difficult weight selection in the multi-object method is solved.

A pressure wavefield and a normal velocity wavefield measured on a smoothly shaped acquisition surface by towed dual-sensor marine seismic streamers are decomposed into up-going and down-going pressure and particle velocity components on an observation level between the acquisition surface and a sea surface of undetermined shape. The up-going and down-going pressure and particle velocity components are extrapolated iteratively in steps from the observation level toward the sea surface. An image point and a reflection coefficient of the sea surface at the image point are determined from the iteratively extrapolated up-going and down-going pressure and particle velocity components.

A pressure wavefield and a normal velocity wavefield measured on a smoothly shaped acquisition surface by towed dual-sensor marine seismic streamers are decomposed into up-going and down-going pressure and particle velocity components on an observation level between the acquisition surface and a sea surface of undetermined shape. The up-going and down-going pressure and particle velocity components are extrapolated iteratively in steps from the observation level toward the sea surface. An image point and a reflection coefficient of the sea surface at the image point are determined from the iteratively extrapolated up-going and down-going pressure and particle velocity components.

A particle counter (10) passes a sample stream of a carrier gas or fluid containing particles (72) through an elongated, flattened nozzle (16) and into a view volume (18) formed by an intersection of the sample stream and a laser beam (13). Particles entrained in the sample stream scatter light rays while passing through the view volume. The scattered light is collected by an optical system (26) and focused on to a detector (40). The magnitude of signal coming from the detector is indicative of the particle size. To correct for variances in particle velocity and light beam intensity across the view volume, flow aperturing is used. Flow aperture modeling (Eqs. 1-7) provides a format for designing the nozzle such that the lateral velocity profile matches the laser beam lateral intensity profile, thereby providing uniform detection sensitivity to laser light scattered from monodisperse particles distributed laterally across the view volume. Uniform detection sensitivity of monodisperse particles provides accurate particle sizing resolution.

The cold spraying process according to the invention uses cold gas streams whose properties (temperature (T), particle density (p), pressure (p), particle velocity (v)) are variably changed such that they can be adapted to the desired properties of the coatings.

An improved automatic feedback control scheme enhances plasma spraying of powdered material through reduction of process variability and providing better ability to engineer coating structure. The present inventors discovered that controlling centroid position of the spatial distribution along with other output parameters, such as particle temperature, particle velocity, and molten mass flux rate, vastly increases control over the sprayed coating structure, including vertical and horizontal cracks, voids, and porosity. It also allows improved control over graded layers or compositionally varying layers of material, reduces variations, including variation in coating thickness, and allows increasing deposition rate. Various measurement and system control schemes are provided.

The invention discloses an improved particle swarm optimization (PSO) algorithm of solving the zero-waiting flow shop scheduling problem. Firstly, parameter initialization and population initialization are carried out, wherein initial workpiece sequences are generated, then a factorial encoding method is used to map all permutations to integers to form an initial population, and finally, a feasible initial velocity set is randomly generated; particles are moved; the population is updated through an original PSO population updating strategy, a new population is mapped to corresponding workpiecesequences, and work completion time of each new workpiece sequence is evaluated; an improved variable neighborhood search (VNS) algorithm is used for a local search, and results obtained by the search are used for replacement; a population adaption (PA) operator is used to increase diversity of the population; and checking of a termination condition is carried out, if the termination condition ismet, a process is stopped, and values of variables and corresponding sequences are returned to be used as a final solution, and otherwise, particle velocity is continuously updated. The method has the advantages of improving a particle swarm optimization algorithm, improving global search capability, and avoiding too early convergence.

The invention discloses a pressure speed method sound field separation method, a measured sound field is provided with a measuring surface S; a sound pressure sensor is adopted to measure the sound pressure on the measuring surface S, and a particle velocity sensor or a sound intensity probe is adopted to measure the particle speed on the measuring surface S; both sides of the measuring surface S are provided with the imaginary source surfaces S1 <*> and S2 <*> which are provided with the equivalent sources; the transfer relationship between the equivalent sources and the sound pressure and the particle speed on the measuring surface S is constructed; the separation of sound source radiation sound pressure and the particle speed of both sides on the measuring surface according to the transfer relationship is realized; the sound field separation is realized by measuring the speed relation of sound pressure and particle on each surface; and the equivalent source method is adopted as the sound field separation arithmetic, the calculation stability is good, the calculation precision is high, and the implement is simple. The method can be widely applicable to the near-field acoustic holography measurement in the environments of internal sound field or noisy sound, the sound intensity method sound source identification in the noisy environment, the material reflection coefficient measurement, and the separation of the scattering sound field.

Embodiments of a directional acoustic sensor or acoustic velocity microphone are disclosed that include a sensor frame structure, a support means, and a buoyant object. The buoyant object is suspended in the sensor frame structure using the support means. The buoyant object has a feature size smaller than a wavelength of the highest frequency of an acoustic wave in air. The buoyant object receives three-dimensional movement of the air excited by the acoustic wave. The three-dimensional movement that the buoyant object receives is detected using a detection means. A particle velocity of the acoustic wave is derived from the three-dimensional movement of the buoyant object using the detection means. The detection means can be an optical detection means, an electromagnetic detection means, or an electrostatic detection means. An acoustic image of the acoustic wave can be determined by distributing two or more directional acoustic sensors a multi-dimensional array.

A method is provided for high velocity air plasma spraying (APS) application of a protective coating system, such as a bond coat with or without an overlying ceramic thermal barrier coat, to a superalloy metal substrate. Application of MCrAlY alloy bond particles (where M is at least one of iron, cobalt, or nickel) onto the metal substrate is maintained at a particle velocity of at least 400 meters per second (m / s), for example within a range of 400 m / s to 700 m / s. The resulting bond coat on the metal substrate has a surface roughness of about 300 to about 500 μinch Ra, and a density of at least 90% of theoretical density. The protective coating may include a ceramic thermal barrier coat applied over the bond coat by any suitable process.

The invention provides a transmission and transformation project construction cost assessment method and device. The transmission and transformation project construction cost assessment method comprises the following steps: input historical sample data of a transmission and transformation project are received; iterations, inertia weight, learning factors, particle velocity of a chaos particle swarm and the population size of the particle swarm are initialized to build a chaos particle swarm model; according to the chaos particle swarm optimization, parameters of the chaos particle swarm model are optimized; according to the historical sample data and the optimized chaos particle swarm model, optimal values of the iterations, inertia weight and learning factors of the chaos particle swarm model are determined; according to the determined optimal values of the iterations, inertia weight and learning factors, penalty coefficients, insensitive coefficients and kernel function parameters of a least square support vector machine model are determined respectively to build the least square support vector machine model; input actual sample data of the transmission and transformation project are received; according to the actual sample data of the transmission and transformation project and the built least square support vector machine model, a construction cost assessment result of the transmission and transformation project is generated.

A method of processing multi-component seismic data acquired at a receiver station comprises determining a calibration filter that calibrate a first component of the seismic data relative to a second component of the seismic data in order to compensate for differences in coupling between the two components. The determination of the calibration filter comprises processing the data in the common shot domain. This allows optimisation criteria to be applied to the up- and down-going constituents of particle velocity, and this is simpler than prior art methods of applying optimisation criteria to the up-going and down-going constituents of the pressure.

The invention discloses a single-shot multi-information diagnostic target. The diagnostic target is characterized in that a positive plate impacts a substrate at a high speed, and enters a sample through the substrate to conduct shock compression; the shock wave is reflected back and forth between the substrate with high shock impedance and a composite window to compress the sample multiple times so as to generate a high-temperature and high-pressure plasma and send light radiation; the light radiation enters a multi-channel radiation pyrometer and a time-resolved spectrometer through the composite window and a fiber bundle to synchronously measure the shock luminous radiation history and the time-resolved transient spectra; the interface particle velocity of the shock wave changes when the shock wave is reflected between the sample and the window interface; and the particle velocity profile is measured by a Doppler probe system. The state parameters of the sample compressed for multiple times can be determined through correlation analysis of the particle velocity profile and the shock luminous radiation history in combination with the impedance matching method. The diagnostic target has a compact structure, and can achieve the synchronous measurement of multiple state parameters of the plasma in the same single-shot experiment, such as shock wave velocity, particle velocity, pressure, temperature, density and time-resolved transient spectra.

The invention discloses a particle spring structure based universal garment three-dimensional model simulation method. The method comprises: obtaining information of a top point and a triangular surface of a garment model, constructing an adjacency relation, and establishing a particle spring structure model of a garment; and based on a numerical solving algorithm, obtaining a motion track of a mass point at t moment by iterative operation. The invention furthermore discloses a particle spring structure based universal garment three-dimensional model simulation system. According to the simulation method and system, a spring model is simplified into a structure spring and a bending spring, so that while a simulation result is not influenced, the calculation amount is reduced and the simulation efficiency is improved; a particle motion prediction mechanism is introduced, so that the reliability and error correction capability of simulation are improved, and the simulation result better conforms to physical properties of garment cloth; and particle velocity data do not need to be calculated and only the position of the top point on the triangular surface needs to be calculated, so that the simulation speed is increased.

The invention discloses a kind of particle measurement method about penetration ratio relation spectrum method and its equipment. It is characterized in that this invention uses of the impulsive signal characteristic of the particle penetration ratio signal of the particle shining under the sharp beam and treats the penetration ratio impulsive signal so it can get the particle velocity, the particle grain size distribution and the information of particle density. This method is named penetration ratio impulsive related spectrum method which adopts the light signal dynamic characteristic and the related treatment of signal. It can measure the particle grain size distribution, density, and velocity above micron class. The benefit effect of invention I that the measurement method and equipment are easy, low cost, and realizes the on-line and real-time detection and at the same time it realizes the test of particle grain size distribution, density, and velocity. It can be used in science study, the production of chemical energy and the course control, the protection of environment, the detection of water quality and the measurement of particle and so many fields.

The invention relates to a task scheduling method for an embedded heterogeneous multiprocessor system. The prior algorithm needs to spend much time in optimizing, and lacks the ability of solving practical problems. The method comprises the steps of: firstly, dynamically adjusting particle velocity V to obtain an optimal value of the velocity; then, adjusting inertia weight w according to the optimal value of the particle velocity; and finally, simulating the task scheduling method. The invention aims at the balance of the global searching ability and the local searching ability of an embedded multiprocessor system with complicated function and the problem of the decrease of the searching ability of a particle swarm optimization algorithm at the late period of iterations to provide the task scheduling method which optimizes the balance thereof and promotes the searching ability thereof at the late period of the iterations by adjusting the flight time and the inertia weight.

The invention provides a method for modeling a sea wave significant wave height inversion model based on particle swarm optimization (PSO) self-adaptive piecewise linear fitting, and belongs to the technical field of sea wave parameter inversion. The method comprises the steps of performing outlier removal processing on data, performing sparsification processing on the data, initializing parameters in a particle swarm, initializing a particle speed, updating the particle speed, updating particle displacement and the like. According to the method for modeling the sea wave significant wave height inversion model based on self-adaptive piecewise linear fitting, the wave height is subjected to inversion by utilizing a particle swarm optimization, so that the function of a conventional algorithm can be realized, the precision of the conventional algorithm is achieved, and more precise wave height inversion can be performed; and moreover, when the number of the pieces in the method is more than or equal to two, the modeling precision is higher than that of a conventional modeling method. The inversion model modeled by the method has higher inversion precision compared with the inversion model modeled by the conventional method, and moreover, the method for modeling a sea wave significant wave height inversion model based on PSO self-adaptive piecewise linear fitting is wide in applicability and high in flexibility.

Embodiments of a directional acoustic sensor or acoustic velocity microphone are disclosed that include a sensor frame structure, a support means, and a buoyant object. The buoyant object is suspended in the sensor frame structure using the support means. The buoyant object has a feature size smaller than a wavelength of the highest frequency of an acoustic wave in air. The buoyant object receives three-dimensional movement of the air excited by the acoustic wave. The three-dimensional movement that the buoyant object receives is detected using a detection means. A particle velocity of the acoustic wave is derived from the three-dimensional movement of the buoyant object using the detection means. The detection means can be an optical detection means, an electromagnetic detection means, or an electrostatic detection means. An acoustic image of the acoustic wave can be determined by distributing two or more directional acoustic sensors a multi-dimensional array.

The invention discloses a testing method and apparatus for acquiring coagulation efficiency of a pollutant particle in different physical field environments. According to the invention, a compressed water-gas mixture is atomized by using an atomization nozzle; water mist passes through an electric field environment, so modified water mist is obtained, and the particle velocity and particle size of the modified water mist are detected by using a dynamic particle analyzer; then the atomization nozzle is closed, pollutant particle generation equipment is started, the particle concentration of the pollutant particle before coagulation is detected by using an electric low pressure impactor, and the particle velocity and particle size of the pollutant particle before coagulation are detected; and then the atomization nozzle is opened, the modified water mist is allowed to coagulate in fluid measurement and control equipment together with the pollutant particle, and the concentration of the residual pollutant particle is detected after settlement of a coagulation product. The electric field environment is changed into a magnetic field environment and a sound field environment, then the above-mentioned steps are repeated, and the particle concentrations before and after coagulation are compared so as to obtain the coagulation efficiency influence law curve of the pollutant particle in each physical field environment; and thus, powerful bases are provided for treatment of air pollution.