75 results about "Density field" patented technology

Simultaneous Dynamical Integration modeling techniques are applied to global placement of elements of integrated circuits as described by netlists specifying interconnection of morphable-devices. Solutions to a system of coupled ordinary differential equations in accordance with Newtonian mechanics are approximated by numerical integration. A resultant time-evolving system of nodes moves through a continuous location space in continuous time, and is used to derive placements of the morphable-devices having one-to-one correspondences with the nodes. Nodes under the influence of net attractive forces, computed based on the interconnections between the morphable devices, tend to coalesce into well-organized topologies. Nodes are also affected by spreading forces determined by density fields that are developed based on local spatial node populations.

A method of harvesting vibrational energy is provided. This method involves generating a high magnetic flux density field within a current induction conductor such as an induction coil. The high magnetic flux density field is generated between two same pole magnets. The high magnetic flux density field may be displaced relative to the current induction conductor with vibrational energy. These displacements then cause the current induction conductor to be energized. The two same pole magnets are mounted between piezoelectric transducer (PZT) materials. These PZT materials generate an electric potential when the PZT materials are subject to the mechanical stresses of the vibrational energy. The electrical energy translated from the vibrational energy through both the energized current induction conductor and stress PZT materials may then be used to power a power circuitry or be stored for later use.

The invention provides a method for calibrating a supersonic flow field density field. According to the method, a supersonic flow field density-nanoparticle-based planar laser scattering (NPLS) image gray curve is calibrated by adopting a comprehensive oblique shock wave and expansion wave calibration method based on an NPLS technology. The method comprises the following steps of: 1, uniformly scattering trace particles in supersonic incoming flow, and shooting a particle image according to the instruction of a computer by a charge coupled device (CCD); 2, continuously adjusting obliqueness of an attack angle alpha in a supersonic wind tunnel, and acquiring a group of (rhoi, Ii) (i=1, 2, L, n-1) data by changing the oblique attack angle alpha; 3, placing expansion wave generators in the supersonic wind tunnel, and acquiring the other group of (rhoi, Ii) (i=n, n+1, L, N) data by placing the expansion wave generators with different deflection angles; and 4, performing polynomial fitting on the two groups of data to obtain the supersonic flow field density-NPLS image gray relation curve, namely rho=alapha0+alpha1I+alpha2I2+alpha3I3+K. The method aims to solve the technical problems of low spatial resolution and low signal-noise ratio and high error on measurement of a low-density area.

The invention discloses a kind of method of measurement the solid particle three-dimensional density field in the gas and solid two phase flow, velocity field and equipment. The particle flux transmitting tube is laid at the front of high rate stereoscopic vision system which is consisted by the double look-out angle lens stereoscope and the high rate camera and the jet stream particle is refracted through the double look-out angle lens stereoscope mirror face and the single high rate camera target area can achieve the particle flux graphic with two different angles at the same time and after the graphic is input the computer a program module which is consisted by the pattern recognition algorithm procedure and three-inversion projection algorithm procedure treats the particle diagram and then get the transient three-dimensional density field. The program module treats series microsecond class time sequence changeable particle graphic and gets the particle three-dimensional movement trace and the velocity field. It is stabilize by using the single camera system and overcomes the problem of multiple camera system's constructer is complex and the synchronism is bad.

The invention provides a full field measuring system and method of reynolds stress of a compressible turbulent flow. The method comprises the steps that: nano trace particles are put into an experimental section of a wind tunnel by a nano particle generator; a second control signal is sent out by a synchronous controller according to a first control signal of a computer; after the second control signal is received by a charge coupled device (CCD) camera, a flow field in the experimental section of the wind tunnel is exposed, and meanwhile, laser beams are successively emitted by a double-cavity laser within the time of exposure of the CCD camera; two nano particle images relevant to the time are obtained by the CCD camera; and the velocity field and the density field of the flow field are simultaneously obtained by the computer according to the two nano particle images relevant to the time, and then the reynolds stress of the compressible turbulent flow is obtained. Through the full field measuring system and method, the technical problem that the velocity field and the density field cannot be simultaneously obtained can be solved, and then the aims that the velocity field and the density field of the compressible turbulent flow are simultaneously measured and the reynolds stress of the compressible turbulent flow is obtained according to the velocity field and the density field which are simultaneously measured are achieved.

Simultaneous Dynamical Integration modeling techniques are applied to global placement of elements of integrated circuits as described by netlists specifying interconnection of morphable-devices. Solutions to a system of coupled ordinary differential equations in accordance with Newtonian mechanics are approximated by numerical integration. A resultant time-evolving system of nodes moves through a continuous location space in continuous time, and is used to derive placements of the morphable-devices having one-to-one correspondences with the nodes. Nodes under the influence of net attractive forces, computed based on the interconnections between the morphable devices, tend to coalesce into well-organized topologies. Nodes are also affected by spreading forces determined by density fields that are developed based on local spatial node populations.

A real-time algorithm for rendering an inhomogeneous scattering medium such as fog is described. An input media animation is represented as a sequence of density fields, each of which is decomposed into a weighted sum of a set of radial basis functions (RBFs) such as Gaussians. The algorithm computes airlight and surface reflectance of the inhomogeneous scattering medium. Several approximations are taken which lead to analytical solutions of quantities such as an optical depth integrations and single scattering integrations, and a reduced number of integrations that need to be calculated. The resultant algorithm is able to render inhomogeneous media including their shadowing and scattering effects in real time. The algorithm may be adopted for a variety of light sources including point lights and environmental lights.

The invention relates to the technical field of flame three-dimensional detection and reconstruction. More specifically, the present invention provides a device and a method for measuring a flame temperature field based on a single-camera endoscopic background schlieren tomography technology. An imaging system combining a high-speed camera and an all-in-one endoscope is adopted, a background schlieren chromatography technology based on a refractive index gradient measurement principle is utilized, and the deflection angle of light passing through to-be-measured gas is obtained by shooting twopictures when to-be-measured flame exists and does not exist and combining an optical flow algorithm or a cross-correlation algorithm. And then a refractive index field of the flame is reconstructed through an algebraic iterative algorithm, the refractive index field is deduced to a density field in combination with a Gladstone-Dale formula, and the density field is deduced to a temperature fieldaccording to an ideal gas state equation. The device is simple, the test cost is low, and the reconstruction of a transient flame three-dimensional temperature field can be realized only by one high-speed camera.

The invention provides a dynamic volume cloud construction and drawing method comprising the following steps that a cloud layer data field is constructed; and a cloud layer is drawn according to the cloud layer data field. A three-dimensional cloud layer thickness field is generated through superposition with Perlin noise acting as the basic noise, and then a density field is generated with the thickness field acting as the basis so that the shapes required by various three-dimensional volume clouds and dynamic changing clouds can be constructed, and the efficient cloud layer drawing effect can be acquired by an accelerated light depth and light illumination calculation method.

The invention discloses a fluid simulation method based on video reconstruction and eulerian model coupling. The fluid simulation method comprises the steps of 1) reconstructing a three-dimensional density field of each frame of a fluid according to an input video; 2) solving an N-S equation by adopting an eulerian method, and updating the speed field and density field of the fluid; 3) taking the reconstructed density field of adjacent two frames as prior information and taking the result of the eulerian method as correction to reconstruct a three-dimensional speed field of the fluid; and 4) guiding the eulerian fluid simulation by using the reconstructed density field and speed field to generate a new animation effect. By adoption of the fluid simulation method, the density field and the speed field of the fluid can be reconstructed with relatively high precision; and by tightly coupling the reconstructed data and a fluid geometrical model, a fluid animation effect which is more closer to an actual condition can be obtained, and controllable fluid details can be added.

The invention relates to a quick volume data skeleton extraction method based on rendering. The quick volume data skeleton extraction method comprises the following steps: under upper, lower, front, rear, left and right viewpoints, using a RayCasting direct volume rendering algorithm to render three-dimensional volume data, so as to obtain six two-dimensional images; extracting the contours and partial key feature lines of all the two-dimensional images obtained through direct volume rendering; projecting the obtained contours and partial key feature lines of the two-dimensional images back to a three-dimensional space, so as to obtain a three-dimensional standby curve; sampling the space, calculating curve density of space sampling points and constructing a curve density field; after the curve density field is obtained, obtaining the gradients of the sampling points through a three-dimensional Sobel operator; according to the gradient values of the sampling points, calculating the curve directions of the sampling points through a least-square method; assigning the curve direction to the voxels of the corresponding three-dimensional volume data; according to the directions of the voxels, constructing a bounding box and calculating the average value of the voxels of the bounding box to obtain characterization nodes; connecting the characterization nodes and smoothing the connecting curve, so as to obtain a three-dimensional volume data skeleton.

The invention relates to an air flow simulating method based on physical simulation. The method converts low-speed particles into a grid model by solution of the traditional particle model, and simultaneously transfers high-speed particles to a temporary grid model while solving, and finally outputs grid model results and density field superposed by the temporary grids and renders. The invention also provides an air flow simulating system based on physical simulation. The method and the system thereof can effectively carry out simulation requirements of air containing low-speed and high-speed air simultaneously and can provide greater expression capability and more real simulation effect.

A method for measuring air mass flow into a compressor section of a gas turbine engine is provided. Air is introduced into a chamber upstream from an inlet of the compressor section. The chamber includes filter packages with at least some of the filter packages including a flow sensor and a filter structure, the filter structure filtering the air. The flow sensors measure the velocity of the air flowing through the corresponding filter package. A controller uses the air flow sensor signal data to characterize a two dimensional flow field through the chamber. Additionally, a plurality of temperature, humidity, and static pressure sensors are disposed throughout the filter packages. The controller uses the temperature, humidity, and static pressure sensor signal data to characterize a two dimensional density field through the chamber. The controller combines the flow field with the density field to calculate a two dimensional air mass flow field.

The invention discloses an equivalent method for cross-scale thermal analysis of a fiber toughening composite material based on multiple criteria such as a cross entropy and the like. The method comprises the following steps: establishing a random representative unit and enabling CMC fiber reinforcement phases to be randomly distributed by utilizing a Monte-Carlo method in the unit; establishing SRVEs for multiple times and performing finite element simulation on the SRVEs to obtain statistic data of thermal physical quantities such as an equivalent heat conduction coefficient of the composite material, a material temperature gradient field and a thermal flux density field; and adjusting the size of a PRVE, determining the critical size of the PRVE after multiple convergence criteria such as a mean value, a variance, the cross entropy and the like of the thermal physical quantities are met, obtaining the distribution of the equivalent heat conduction coefficient of the composite material, the material temperature gradient field and the thermal flux density field, and establishing a corresponding relationship between a microscopic structure and a macroscopic property. According to the method, heterogeneous characteristics and existent physical dispersity in the composite material are fully considered and judgment bases are provided for how to determine the critical size of the PRVE in thermal analysis of the composite material, so that the corresponding relationship between the microscopic structure and the macroscopic property can be established more accurately.

The invention discloses a novel user controlled method for generating highly structured triangular meshes, comprising the following steps: (1) generating corresponding characteristic constraint and a density field on an input mesh model according to user requirements, and generating a corresponding field of direction according to the characteristic constraint and the user requirements; (2) constructing three scalar fields on the input mesh model, wherein the direction of contour lines of each scalar field is in accordance with that of the field of direction in step (1), the geodesic distance between adjacent contour lines of each scalar field is 1/mu on the input mesh model, and mu represents the density field in step (1); and (3) extracting the contour lines of each scalar field, and forming the triangular meshes by intersecting the extracted contour lines. The invention has the beneficial effects that the highly structured triangular meshes can be generated; optimized singular point distribution can be automatically obtained; and edge direction, sampling density, characteristics alignment and the like of the mesh are directly controlled by the user, and at the same time, facet quality is maintained.

The invention discloses a heavy medium cyclone separation device applied to separation of non-magnetic ore such as coarse slime. The heavy medium cyclone separation device comprises a cyclone column, and a cyclone cone arranged at the lower end of the cyclone column, wherein a cyclone feeding pipe is arranged at the upper part of the cyclone column; a cyclone center pipe which stretches into the cyclone column is arranged in the cyclone column; an inner magnetic pole excitation coil is arranged on the exposed section of the cyclone center pipe; an outer magnetic pole group is arranged at the periphery of the lower part of the cyclone column; the outer magnetic pole group consists of multiple electromagnets; outer magnetic pole excitation coils of the electromagnets are connected in series together and load exciting current I1together, and the inner magnetic pole excitation coils load current I2; the magnetic polarity on one side, which is close to the cyclone column, of the electromagnets is different from the magnetic polarity at the lower end of the cyclone center pipe. The magnetic field distribution in a cyclone area of the cyclone is controlled by adjusting the current of inner and outer dual-control electromagnetic pole coils, and motion of magnetic mineral powder in a special heavy medium cyclone is subjected to magnetic interference, so that a density field inside the cyclone is changed, and an effect of controlling separation of the heavy medium cyclone is achieved.

The invention relates to a reconstruction method of p and s-wave disintegration elastic wave used for oil exploration, comprising the following procedures: first, determining reconstruction parameters during wave field reconstruction according to actual parameters acquired by a observation system; second, reading a velocity field and a density field of lengthwise and transverse wave layers which is in conformity with the local underground geological structure and is acquired through seismic data in the early phase; third, performing interpolation for a disintegration field again according to the parameters of the observation system and the disintegration field; fourth, performing the acquired wave field reconstruction record processing identical to the actual data to acquire a corresponding profile; fifth, comparing a reconstruction profile and a data collection profile to determine oil gas reservoir structure. The invention has the advantages of effective wave field reconstruction under two-dimensional condition, applicability to wave field reconstruction of any complex structure, ability to determine underground oil gas reservoir structure, high precision and efficiency and low frequency dispersion.

The invention discloses a body movement enhancement visualization method and a body movement augmented reality system. The method comprises the steps: extracting body skeleton movement information through body movement obtaining equipment; setting the body skeleton movement information as the boundary condition and an external force; carrying out the simulation of airflow movement at an overlapped layer through a method of computational fluid mechanics, and carrying out the synchronous display of the change of a density field under the airflow condition and the movement data, thereby improving the visualization effect of each type of movement. The method is suitable for the visualization of slight and instantaneous movement. Through the calculation and automatic synthesis of visual data with the enhanced movement effect to an original body movement video, there is no need to manually carry out the subsequent processing of movement data, and the method can cooperate with an augmented reality glasses or other camera display integrated equipment, and is used in the field of augmented reality.

The invention relates to a three-dimensional smoke density field generating method based on single-viewpoint images. Three-dimensional smoke density field can be regenerated on a computer by the aid of data of smoke images shot from a single viewpoint to create three-dimensional animation of smoke. The method includes: firstly, using the image segmentation method to segment existing smoke data into local smokes; secondly, computing principal direction and outline basis function of each local smoke according to the local smokes; thirdly, using the proceduring method to generate the three-dimensional density fields of the local smokes according to the principal direction and outline basis function of each local smoke; and fourthly, joining the three-dimensional density fields to generate a continuous three-dimensional smoke density field. The three-dimensional smoke density field generating method based on single-viewpoint images has the advantages that firstly, data acquisition is simple, and only one camera is used for acquiring smoke data from one viewpoint; and secondly, processing is quick, and the three-dimensional smoke density field can be generated in real time.

The invention relating to the field of aerodynamics discloses a three-dimensional structure measuring device and measuring method of an incident shock wave. The measuring device comprises Laval nozzle, an equal straight pipe, a tapered wedge, a rotary angle disk, a guide rail, a light source, a background pattern plate, a high speed camera, and the like. The measuring device having a simple structure is operated conveniently; and because the model employs the integrated flow/measurement design, three-dimensional reconstruction of the incident shock wave and measurement of the flow field density field and the wall friction field are realized.

The invention discloses a method for measuring a wind tunnel density field based on video and a sub-pixel technology, which includes: S1, carrying out image acquisition on a density field before and during a wind tunnel test respectively to obtain corresponding static density field measurement images and dynamic density field measurement images; S2, locating centers of circles in the dynamic density field measurement images based on a sub-pixel positioning technology; and S3, calculating an optical refractive index with position change of coordinates of the centers of circles in the dynamic density field measurement images and coordinates of the centers of circles in the static density field measurement images so as to calculate and obtain a wind tunnel density field. The method provided by the invention is able to calculate the wind tunnel density field by comparing the position change of the centers of circles in background images during and before the test based on video measurement. Compared with the prior art, the method has the advantages of being simpler and more convenient, high precision and fast measuring speed.

The invention discloses a tracer-particle-based non-contact density profile measuring method in an internal wave experiment. A PIV device is arranged at one side of a water tank. Saline water with thedensity lower than that of a tracer particle is placed on the bottom of the water tank and then saline water with the density higher than that of the tracer particle is placed, wherein the saline water contains tracer particles. Laser with the fixed wavelength and the fixed power irradiates the saline water with tracer particles mixed; the PIV device shoots an experimental observation area continuously; the tracer particles are displayed as white light points on an obtained grayscale image and the rest part is displayed in black; and on the basis of the number of white light points in a certain area on the grayscale image, the particle number is estimated by inversion and thus the water density is deduced. According to the method for acquiring velocity field and the density field information of an internal wave simultaneously by the PIV, the data consistency is high. The method can be applied to various marine fluid mechanics experiments.

The invention discloses a fluid animation rendering method based on detail capturing and form correcting in the technical field of computer image processing. The method comprises the following steps of: performing fluid simulation and optimizing a speed field in an initial scene according to a Navier-Stokes equation; updating a corresponding density field and a corresponding temperature field according to the optimized high-precision speed field by adopting a semi-Lagrangian method so as to be used for rendering and next-frame simulating; and finally, rendering an updated density field into a fluid animation. More colorful details can be captured through a high-speed discrete sine transform operator, the calculation scale of a part with highest time consumption in an original simulation method can be reduced through using a down-sampling or octree method, simultaneously the result is corrected, and the functions of increasing the simulation speed and keeping fluid simulation details are realized. Compared with the prior art, according to the method, the simulation speed is relatively high, and the fluid simulation details with high more accuracy can be acquired.