Patents
Literature
Patsnap Copilot is an intelligent assistant for R&D personnel, combined with Patent DNA, to facilitate innovative research.
Patsnap Copilot

617 results about "SIMPLE algorithm" patented technology

In computational fluid dynamics (CFD), the SIMPLE algorithm is a widely used numerical procedure to solve the Navier-Stokes equations. SIMPLE is an acronym for Semi-Implicit Method for Pressure Linked Equations.

Movement human abnormal behavior identification method based on template matching

The invention relates to a movement human abnormal behavior identification method based on template matching, which mainly comprises the steps of: video image acquisition and behavior characteristic extraction. The movement human abnormal behavior identification method is a mode identification technology based on statistical learning of samples. The movement of a human is analyzed and comprehended by using a computer vision technology, the behavior identification is directly carried out based on geometric calculation of a movement region and recording and alarming are carried out; the Gaussian filtering denoising and the neighborhood denoising are combined for realizing the denoising, thereby improving the independent analysis property and the intelligent monitoring capacity of an intelligent monitoring system, achieving higher identification accuracy for abnormal behaviors, effectively removing the complex background and the noise of a vision acquired image, and improving the efficiency and the robustness of the detection algorithm. The invention has simple modeling, simple algorithm and accurate detection, can be widely applied to occasions of banks, museums and the like, and is also helpful to improve the safety monitoring level of public occasions.
Owner:XIDIAN UNIV

Spatial circular geometric parameter binocular stereo vision measurement method

The invention discloses a spatial circle geometrical parameter dual-eye solid visual measurement method suitable for non-contact type online measurement of the spatial circle geometrical parameter of an industrial product, aiming at overcoming the existing problems of low measurement precision, slow measurement speed and low automation degree. The method is divided into a calibrating stage, an image processing stage and a spatial circle fitting stage. A neural network technique is firstly adopted to carry out the calibration of a camera; a dual-camera is utilized to carry out the extraction of sub-pixel image edges of the spatial circle, a simple algorithm is developed based on the image gray gradient distribution characteristic so as to realize the match of edge points, the practical 3D spatial coordinates of the circle edges are then obtained, and the geometrical parameters of the spatial circle comprise radius, position of center of circle and orientation of the plane where the spatial circle is arranged are gained by the fitting of the spatial circle with corresponding mathematical geometrical knowledge. The spatial circle geometrical parameter dual-eye solid visual measurement method has fast image processing speed and high automation degree, and has relative measurement error of the spatial circle of superior to plus or minus 0.6% when the plane where the spatial circle is arranged has an angle of about 50 DEG with the image plane.
Owner:JILIN UNIV

Three-dimensional model reconstruction method of tree point cloud data based on partition and automatic growth

The invention relates to a three-dimensional model reconstruction method of tree point cloud data based on partition and automatic growth, comprising the following steps: preprocessing; estimating the main curvature of point cloud; partitioning data according to the main curvature; calculating a framework of a principal branch of branches by the partitioned point cloud belonging to a branch part;leading from the framework of the principal branch of the branches to generate twigs of the branches by the partitioned point cloud belonging to a leaf part; and generating a branch mesh model and adding a leaf model at the ends of the twigs of the branches. In the method, the three-dimensional reconstruction model which is faithful to original entities can be obtained by means of the scanning data of a laser scanner; the reconstruction model of the tree point cloud data can be obtained based on data partition and growth of the twigs of the branches, thus the method has simple algorithm and accurate calculation result; and the calculation result has important application value in the fields such as virtual reality, computer games, natural scene simulation, urban landscape design, film production, three-dimensional reconstruction of trees, agriculture and forestry measurement and the like.
Owner:INST OF AUTOMATION CHINESE ACAD OF SCI

Three-dimensional gesture estimation method and three-dimensional gesture estimation system based on depth data

The invention discloses a three-dimensional gesture estimation method and a three-dimensional gesture estimation system based on depth data. The three-dimensional gesture estimation method comprises the following steps of S1, performing hand region of interest (ROI) detection on photographed data, and acquiring hand depth data, wherein the S1 comprises the processes of (1), when bone point information can be obtained, performing hand ROI detection through single bone point of a palm; (2) when the bone point information cannot be obtained, performing hand ROI detection in a manner based on skin color; S2, performing preliminary estimation in a hand three-dimensional global direction, wherein the S2 comprises the processes of S21, performing characteristic extracting; S22, realizing regression in the hand global direction according to a classifier R1; and S3, performing joint gesture estimation on the three-dimensional gesture, wherein the S3 comprises the processes of S31, realizing gesture estimation according to a classifier R2; and S32, performing gesture correction. According to the three-dimensional gesture estimation method and the three-dimensional gesture estimation system, firstly cooperation of two manners is utilized for dividing hand ROI data; afterwards estimation in the hand global direction is finished according to a regression algorithm based on hand ROI data dividing; and finally three-dimensional gesture estimation is realized by means of the regression algorithm through utilizing the data as an aid. The three-dimensional gesture estimation method and the three-dimensional gesture estimation system have advantages of simple algorithm and high practical value.
Owner:UNIV OF ELECTRONICS SCI & TECH OF CHINA

Optic disc projection location method synthesizing vascular distribution with video disc appearance characteristics

The invention discloses an optic disc projection location method synthesizing vascular distribution with video disc appearance characteristics, which comprises the following steps of: (1) extracting an interest retina fundus image region by use of a mask operation; (2) carrying out normalization enhancement on a fundus image based on an image observation model; (3) achieving extraction and segmentation of the fundus image by using a non-vascular structure inhibition operator and combining with a hysteresis multi-threshold processing technology; (4) setting a vertical window of double main blood vessel width to slide on a blood vessel segmentation image along the horizontal direction and calculating a vascular distribution degree D(x) at each horizontal position x to obtain a distribution degree curve of a horizontal projection, wherein the minimum value point of the curve is determined to be optic disc horizontal coordinate xod; (5) setting a rectangular window side length of which is equal to the optic disc diameter to slide up and down at the horizontal coordinate xod, estimating local region brightness IN(xod, y) and edge gradient information gN(xod, y) respectively, drawing a vertical projection curve reflecting a change of a characteristic value f(y)=IN(xod, y)*gN(xod, y), wherein a maximum value point of the curve is optic disc vertical coordinate yod. The method has a simple algorithm, a high success rate and excellent robustness.
Owner:XIANGTAN UNIV

Vibration monitoring structure and method based on optical fiber polarized light time domain reflection sense

The invention relates to a vibration monitoring structure based on optical fiber polarized light time domain reflection sense, comprising a laser (1), a first coupler (2), a second coupler (7), a third coupler (8), a fourth coupler (11), a fifth coupler (13), an acoustic optical modulator (3), a polarizer (4), a circulator (5), a sensing optical fiber (6), a first analyzer (9), a second analyzer (10), a first detector (12), a second detector (14), a first low-pass filter (15), a second low-pass filter (16), a first analog-to-digital converter (17), a second analog-to-digital converter (18), anFPGA (19) and a microprocessor MCU (20); the method comprises the following steps: measuring the changes of the polarization state of each optical fiber section with time according to a plurality ofmeasurements, combining Fourier transformation technology to obtain frequency spectrum information, and analyzing the frequency spectrum information to obtain vibration information. Compared with theprevious method which is adopted by a POTDR system and carries out iteration operation on polarization state, the method has the advantages of simple algorithm and small data operation and greatly reduces monitoring time and cost of the system.
Owner:NANJING UNIV

Digital background calibration circuit

The invention discloses a digital background calibration circuit used for a high-speed and high-precision pipelined analog-to-digital converter. The digital background calibration circuit comprises a pseudo random number generator, pipelined circuits with calibration functions and a digital background calibration engine. Based on the structure of the traditional pipelined analog-to-digital converter, a primary-stage pipelined circuit and a secondary-stage pipelined circuit are modified in the circuit disclosed in the invention to realize the injection of random signals and the digital background calibration engine is used to associate the random signals so as to realize the real-time extraction and compensation of error information, thereby avoiding the influence of irrational factors of the traditional pipelined analog-to-digital converter (such as capacitor mismatching, limitations of operational amplifier gains and the like) on the conversion precision of the analog-to-digital converter. The technology can lower the design difficulty of an analog circuit and ensure the performance of a system. At the same time, because of the simple algorithm and the low implementation complexity, the calibration circuit can be used to effectively reduce the area of the chip and lower the power consumption of the system, thereby being especially applicable to a high-speed system.
Owner:FUDAN UNIV

Binocular vision depth feature and apparent feature-combined face living body detection method

The present invention provides a binocular vision depth feature and apparent feature-combined face living body detection method. The method includes the following steps that: step 1, a binocular vision system is established; step 2, a face is detected through the binocular vision system, so that a plurality of key points can be obtained; step 3, a binocular vision depth feature and a classification score corresponding to the binocular vision depth feature are obtained; step 4, a complete face area is intercepted from a left image, the complete face area is normalized to a fixed size, and a local binary pattern (LBP) feature is extracted so as to be adopted as an apparent feature descriptor; step 5, a face living body detection score corresponding to a micro-texture feature is obtained; and step 6, the classification score corresponding to the binocular vision depth feature obtained in the step 3 and the face living body detection score corresponding to the micro-texture feature obtained in the step 5 are fused in a decision-making layer, so that whether an image to be detected is a live body can be judged. The binocular vision depth feature and apparent feature-combined face living body detection method of the invention has the advantages of simple algorithm, high operation speed, high precision and the like. With the method adopted, a new and reliable method can be provided for living body face detection.
Owner:SHANGHAI JIAO TONG UNIV
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products