119 results about "Curve fitting algorithm" patented technology

The invention provides a method for tracking a small target with high precision under a complex background and a low signal-to-noise ratio (SNR). The method comprises pre-treating an image under the complex background and low SNR, portioning and extracting the target based on a target adaptive threshold of the binomial distribution judgment rule, adopting a curve fitting algorithm based on Kalmanfilter thinking improvement to carry out motion prediction on the target, using data fusion of infrared and visible light transducers to improve detection probability of the target and reduce false-alarm probability, and when the shape of the target alters, using a shape of which edge characteristics are normalized to identify and seek characteristic invariables so as to achieve precise tracking of the target.

An automatic-tracking device of vehicle movement orbit consists of vehicle terminal, service end and client end. It is featured as selecting position coordinate automatically by vehicle terminal according to preset movement path to set up highway enclosing wall, confirming specific position relative to highway enclosing wall by vehicle terminal according to highway position coordinate and actual position coordinate for judging whether vehicle is in the scope of highway enclosing wall or not.

The invention relates to a method for apperceiving and reconstructing a non-vision structural form of a near space vehicle model. The method comprises the following steps: on the basis of a distributed embedded dispersed bragg fiber grating sensing array, sensing and detecting strain information of each measuring point of a test model, and utilizing a certain curvature conversion algorithm to convert the strain information into curvature information; on the basis of a curvature interpolation, calculating the related coordinate value of each point of wings and frame of the test model according to a three-dimensional space curve fitting algorithm of orthogonal curvature information; utilizing a coordinate fuse algorithm to obtain an absolute coordinate value of each point of the model; and lastly, reconstructing the deformation state and the low-frequency vibrating form of the test model according to a computer graphic processing technology and realizing the three-dimensional visual real-time display for the change in the model form. An experimental system for the method comprises a simulated near space vehicle model, a fiber grating network analyzer with a network service function, a high-performance computer and a display, wherein the fiber grating sensing array is embedded into the surface of the simulated near space vehicle model.

The invention discloses an air conditioner device refrigerating capacity test method based on a multi-dimensional curve fitting algorithm, and belongs to the technical field of air conditioner refrigerating capacity test methods. According to the principle on which the test method is based, a reference prototype physical model of an air conditioner device is established and used as a research object, and a refrigerating capacity mathematical model of the air conditioner device under any work condition is obtained by establishing a multi-dimensional curve fitting mathematical model between the refrigerating capacity of a reference prototype of the air conditioner device and all influencing parameters and conducting training simulation through multiple sets of sample data including the normal condition. By means of the mathematical model, the refrigerating capacity of the reference prototype of the air conditioner device under any work condition can be obtained and used as the theoretical value of the refrigerating capacity of a tested air conditioner device of the same type. Under the same test work condition, the actual refrigerating capacity of the tested air conditioner device is obtained. A refrigerating capacity test device or instrument manufactured through the test method can be used for refrigerating capacity tests of the air conditioner device and is widely used for air conditioner device refrigerating capacity tests of traffic vehicles, ships, civil use and industrial application.

The invention provides a background signal extraction method in radar scattering cross section measurement. The method includes measuring echo signals used for obtaining radar transmission signals reflected by a dihedral angle reflector, isolating the echo signals into in-phase channel signals and orthogonal channel signals, obtaining first complex signals through reconstruction of the in-phase channel signals, obtaining second complex signals through the orthogonal channel signals, respectively obtaining real part signals and imaginary part signals of the first complex signals and the second complex signals by means of a curve fitting algorithm, obtaining the real part signals of background signals according to the real part signals and the imaginary part signals of the first complex signals, and obtaining the imaginary part signals of background signals according to the real part signals and the imaginary part signals of the second complex signals. Due to the fact that the background signals are extracted through the curve fitting algorithm in high precision, the background signal extraction method in the radar scattering cross section measurement solves the problem that robustness is poor in practical engineering application.

This document relates to melting curve analysis of nucleic acids. The method according to first aspect of the invention comprises analyzing a nucleic acid melting curve measured from a sample, the melting curve comprising a sum signal of at least two nucleic acid melt signals and a background signal as a function of temperature. The method further comprises optimizing at least one constant in a temperature-dependent exponential correction function so as to minimize the variation of the nucleic acid melting curve at a temperature region where the target nucleic acids in the sample remain essentially double stranded, and generating a corrected nucleic acid melting curve representative of the nucleic acid melt signal by applying said exponential correction function over the region of the measured melting curve where the strands of the nucleic acids dissociate. According to further aspects, the invention relates to a curve fitting algorithm for precise estimation of melting peak areas and a mathematical transformation for linearization of calibration curve data to enhance the linear measuring range of a competitive PCR assay. The invention provides a powerful tool for analyzing PCR-amplified sample containing two or more different nucleic acids having similar but distinguishable melting temperature.

The invention discloses a robot stable motion control method based on curve fitting modeling and multi-constraint foot point estimation. The method comprises the following steps: (1) a local environment of a swing leg foot end is modeled based on a curve fitting algorithm; (2) a reachable area of the swing leg foot end is fitted by combining with working space of the swing leg foot end according to the fitted local environment; (3) according to the reachable area of the swing leg foot end fitted in the step (2), a multi-constraint foot point estimation algorithm is combined to estimate and analyze a plannable foot point in the reachable area of the swing leg foot end; and (4) according to the steps (1) to (3), a multi-gesture conversion algorithm is combined to analyze a robot joint output position, and the polynomial interpolation operation is performed for a joint corner to finish the stable motion control of a robot under non-structural environment. The stable motion control method is high in terrain adaptability and high in efficiency.

The invention discloses a wavelet transform and curve fitting based pulse wave preprocessing method. The pulse wave pretreatment method includes the following steps of 1), subjecting to acquired pulse condition signals to noise suppression with the wavelet global threshold method; 2), rectifying baseline drift and cycle extraction of the pulse condition signals; 3), smoothing the pulse condition signals on the basis of fitting of Gaussian curves. Compared with the prior art, the pulse wave pretreatment method has the advantages that cycles of the pulse condition signals can be effectively extracted, fitting of pulse condition data is completed only in 120 seconds by operating 3.1GHz on a machine according to the curve-fitting algorithm, average fitting error of 97.62% of pulse conditions is smaller than 0.35, and for the fitting result that the error is larger than 0.35, morphological characteristics of the pulse condition signals are also kept, and no diagnostic information is lost.

The invention discloses a remote monitoring device for mountain cracks. The device consists of a sensor node and a monitoring host. The device uses a GSM network to perform information transmission, adopts a cyclic working mode from working to stopping to monitor the mountain cracks, and meanwhile adopts digital filter and curve fitting algorithm to improve the precision of data acquisition; therefore, the device can implement high-precision and long-distance mountain crack monitoring, and greatly prolongs the working time.

The invention discloses an iris positioning method and equipment. The method comprises steps that an iris identification system obtains an iris image which contains an iris and a pupil to be positioned; that the position of a light spot in the pupil is determined, wherein the light spot is formed by irradiating the pupil with an external light source; that according to the position of the light spot and the gray information of the iris image, a first boundary circle and a second boundary circle used for representing the iris to be positioned in the iris image are determined, wherein the first boundary circle comprises the center of circle and the radius of the first boundary circle, and the second boundary circle comprises the center of circle and the radius of the second boundary circle; and that according to the first boundary circle and the second boundary circle, the iris in the iris image can be positioned. Therefore, the iris identification system can rapidly position the position of the iris by a simple image processing technology and a curve fitting algorithm according to the obtained gray information of the iris image, so that the working efficiency of the iris identification system is improved.

The invention relates to a three-dimensional spinal lateral protrusion reconstructing method based on orthophoric and lateral phases, belonging to the field of computer-aided measurement. The three-dimensional spinal lateral protrusion reconstructing method based on the orthophoric and lateral phases comprises the following specific steps of: firstly, setting beginning and ending seed points at gravity centers of a first thoracic vertebra and a last lumbar vertebra in an X-ray film in the orthophoric and lateral phases respectively; secondly, acquiring gravity centers of other vertebras by reasoning transversely and longitudinally; thirdly, fitting all the gravity center points into a curve by a curve fitting algorithm; fourthly, computing the included angle between the normal of each gravity center point on the curve and the horizontal line and the offset of each gravity center point relative to the first gravity center point, wherein the inclined angle between two gravity center points of orthophoric and lateral phases of a same vertebra and the offsets of the two gravity center points form a spatial three-dimensional parameter; and finally, according to the spatial three-dimensional parameter of each vertebra, translating and rotating the corresponding vertebra in a standard spinal model according to the three-dimensional parameter so as to form a spinal spatial three-dimensional model for pathological changes of a patient suffering from the spinal lateral protrusion. According to the three-dimensional spinal lateral protrusion reconstructing method, the time for performing X-ray scanning on the human body is shortened.

The invention discloses a method and a device for determining a moving trace of an obstacle, and belongs to the field of intelligent traffic. The method comprises the following steps: determining a transverse coordinate of the obstacle in each frame of image of continuous n frames of images acquired by a vision sensor, wherein n is an integer larger than 1; performing curve fitting on the transverse coordinates of the obstacle in the continuous n frames of images according to a preset curve fitting algorithm, thus obtaining the moving trace of the obstacle. According to the method and the device, the images acquired by the vision sensor arranged on a vehicle are subjected to analytic processing, so that the moving trace of the obstacle is determined; the problem that of high complexity during data processing in the relevant technology is solved, and the effects of reducing the detection cost of the obstacle and improving the data processing efficiency of the sensor are achieved. The method is used for determining the moving trace of the obstacle.

The invention discloses an LED plant growth spectrum fitting algorithm. The algorithm is characterized by comprising the following steps: 1, establishing spectrum radiation model of a single LED: performing approximation on a distribution model of radiation intensities along with wavelengths in a unit solid angle on an optical axial direction of the single LED by use of a Gauss distribution function, f(x)=ae<-(x-b)<2>/C<2>>; and 2, carrying out a curve fitting algorithm: according to a superposition principle of spectrums, obtaining a basic mathematic model of spectrum synthesis of multiple LEDs: L(lambda)=sigma KiSi(lambda); and in a fitting process, setting a first wavelength lambda0 and a coefficient K0, and successively solving lambda (i) and Ki by use of a least square algorithm. According to the invention, any one fitting spectrum with quite high similarity with a target spectrum can be obtained through spectrum fitting.

The invention discloses a farmland seedling ridge identification method and system based on semanteme and instance segmentation, and the method comprises the steps: collecting a current farmland image, coding, carrying out instance segmentation and semantic segmentation, clustering, carrying out fitting of feature points, drawing to obtain a seedling line and a furrow line, and the like, whereinthe system comprises a function module for achieving all above steps. According to the invention, seedling ridge detection is carried out by using an end-to-end visual image segmentation training method. The required network scale is reduced to a certain extent, the operation speed is effectively improved. Meanwhile, the embedded vector easy to cluster is obtained through the deep network, then the seedling line and the furrow line are efficiently recognized through the simple clustering algorithm and the curve fitting algorithm, and big data samples can be used for continuously supplementingand improving the accuracy and robustness of the detection method.

The invention discloses a method and device for generating a dental panoramic image on the basis of a CBCT image. The method comprises steps of: determining a seed point in a current axial surface image of a CBCT apparatus, processing the seed point by using a curve fitting algorithm to generate a dental arch line; using a curve surface where the dental arch line is located as a central curve surface, computing body tissue density CT values corresponding to the pixels in the central curve surface according to a set sampling thickness, and generating initial dental panoramic images according to the body tissue density CT values; and determining the gradient factor of an anisotropic diffusion filter formula and processing the initial dental panoramic images with different scales by using the anisotropic diffusion filter formula to generate an final dental panoramic image. The method and device achieve a purpose of obtaining the two-dimensional panoramic image of the entire teeth by using the image processing algorithm on the basis of CBCT three-dimensional data.

The invention relates to a method for improving the ultrasonic thickness measurement accuracy by using curve fitting. The method comprises the following steps: according to the characteristics that an ultrasonic signal is similar to a straight line in a short time period above and below a zero point, and when the signal amplitude is higher, the signal is more similar to the straight line, collecting two adjacent sampling points above and below the zero point at the two sides of the positive maximum peak or the negative maximum peak of an echo signal, fitting a straight line through the sampling points, working out corresponding coordinates of a feature point on the fitted curve, sending the coordinates to a thickness calculating module and calculating the thickness of an object to be measured. The method has the advantages that a curve fitting algorithm is used for compensating sampling precision, so that the ultrasonic thickness measurement accuracy is effectively improved under the condition that the sampling clock frequency is constant so as to meet the requirements on the thickness measurement accuracy in certain occasions, the complexity of hardware implementation is reduced, and the reliability of the implementation is improved.

The invention provides a method for measuring the spatial orientation of a pipeline based on a CMOS image sensor. The method includes the following steps that: a laser light source and a CMOS image sensor are arranged at mechanical centering fixed ends at two ends of a universal joint, an attenuation sheet and a bubble fluorescent ring are arranged between the laser light source and the CMOS image sensor, the initial position of the laser light source is set, so that the initial position of the laser light source can be located at the center of the pipeline, and laser emitted by the laser light source is overlapped with the central axis of the pipeline; the laser light source moves, and the CMOS image sensor acquires one frame of image when the laser light source moves a certain distance each time from the initial position; laser spots and bubble fluorescent rings on the acquired images are processed, so that the pixel positions of the laser spots on a photosensitive surface and the directions of bubbles on the fluorescent rings are obtained, the center position of each laser spot and the position of each fluorescent ring bubbles are recorded; the center of each pixel light spot is converted into the actual physical position coordinates of a light spot center; and the orientation curve of the pipeline is fitted through using a least squares method-based curve fitting algorithm according to the actual physical position coordinates of the light spot center and the directions of the bubbles of the fluorescent rings.