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53 results about "Spatial methods" patented technology

Device and method for recognizing hand shape and position, and recording medium having program for carrying out the method recorded thereon

An object of the present invention is to provide a device and a method for recognizing hand shape and position even if a hand image to be provided for recognition is rather complicated in shape, and a recording medium having a program for carrying out the method recorded thereon.A hand image normalization part 11 deletes a wrist region respectively from a plurality of images varied in hand shape and position before subjecting the images to normalization in hand orientation and size to generate hand shape images. An eigenspace calculation part 13 calculates an eigenvalue and an eigenvector respectively from the hand shape images under an analysis based on an eigenspace method. An eigenspace projection part 15 calculates eigenspace projection coordinates by projecting the hand shape images onto an eigenspace having the eigenvectors as a basis. A hand image normalization part 21 deletes a wrist region from an input hand image, and generates an input hand shape image by normalizing the input hand image to be equivalent to the hand shape images. An eigenspace projection part 22 calculates eigenspace projection coordinates for the input hand shape image by projecting the same onto the eigenspace having the eigenvectors as the basis. A hand shape image selection part 23 compares the eigenspace projection coordinates calculated for the input hand shape image with each of the eigenspace projection coordinates calculated for the hand shape images, and then determines which of the hand shape images is closest to the input hand shape image. A shape/position output part 24 outputs shape information and position information on the determined hand shape image.
Owner:NAT INST OF INFORMATION & COMM TECH +1

Method for self-correction of array error of multi-input multi-output radar system

ActiveCN101251597AHigh Target Angle Estimation AccuracyEffective correctionRadio wave reradiation/reflectionMulti inputRadar systems
The invention discloses a self-correction method of a multi-input multi-output radar system array error, relating to the radar technical field. The method aims to carry out self correction of the reliant amplitude and phase error of a receiving array azimuth on the premise that the transmitting array of a multi-input multi-output radar system. The implementation process of the method is as follows: firstly, by means of the two corrected transmitting array elements of the multi-input multi-output radar system, orthogonal signals are transmitted; then, the echo signals of the transmitting array elements are separated by means of the orthogonality of transmitting signal through adopting a matched filtering method; an auto correlation matrix and a cross correlation matrix are established by means of the echo signals; a real guide vector and a target angle of an array are estimated by means of a rotary invariant subspace method; finally, by means of the real guide vector and the target angle of the array obtained through estimation, the array azimuth reliant amplitude and phase error can be corrected. The self-correction method can be used in the array error correction field of a multichannel radar system.
Owner:XIAN CETC XIDIAN UNIV RADAR TECH COLLABORATIVE INNOVATION INST CO LTD

Image retrieval method, image retrieval program, and image registration method

An image retrieval method comprising: a step of extracting at least one query feature vector from a query image on which a subject of the image retrieval is captured, the query feature vector representing a local feature of the query image; a step of accessing an image data base in which a plurality of reference images are stored previously, each reference image being stored in conjunction with learning images generated therefrom and reference feature vectors representing local features of the reference image and the learning images; a comparing step of comparing the query feature vector with the reference feature vectors stored in conjunction with each reference image using an approximate nearest neighbor search to find a reference feature vector approximately nearest to the query feature vector; and a selecting step of selecting a reference image with which the found reference feature vector is stored in conjunction from the reference images as a retrieval result wherein: the learning image is generated by adding a defocus and/or a motion-blur effect likely to occur on capturing the subject to each reference image, the reference feature vectors are extracted from each reference image and the learning image corresponding to the reference image respectively using the scale-space approach, the query feature vector is extracted from the query image using the scale-space approach, and each of the above steps is executed by a computer.
Owner:OLYMPUS CORP

Method for self-correcting coupling error of electromagnetic vector sensor array

The invention discloses a method for self-correcting a coupling error of an electromagnetic vector sensor array. According to the method, an ideal electromagnetic vector sensor is additionally arranged to be used as an auxiliary array element and forms a receiving array with the electromagnetic vector sensor array to be corrected, the receiving array receives the completely polarized transverse electromagnetic wave signal data of a far field, the autocorrelation matrix of the sample data is calculated, the real electromagnetic field vector and electromagnetic vector having errors of the signal are estimated through a subspace method, the obtained estimated value of the real electromagnetic field vector and the estimated value of the electromagnetic field vector having errors are used to estimate the coupling error variance, the coupling error matrix is constructed according to the coupling error variance and the inverse matrix is calculated, and the data received by the electromagnetic vector sensor to be corrected are pre-multiplied by the inverse matrix of the coupling error matrix so as to correct the coupling error. The method disclosed by the invention has a simple solving process and small calculated amount, the real electromagnetic filed vector and the electromagnetic field vector having coupling errors of the signal can be estimated, and higher coupling error estimation accuracy can be achieved.
Owner:XIDIAN UNIV

Alternating excitation low-temperature heating method for lithium ion battery based on temperature change

ActiveCN109786897AAchieve low temperature self-heating effectGood self-heating effect at low temperatureSecondary cellsInternal resistanceEngineering
The present invention discloses an alternating excitation low-temperature heating method for a lithium ion battery based on temperature change, and belongs to the technical field of charging of lithium ion power batteries. The present invention solves the problem that the existing lithium ion battery has poor charging and discharging performance in a low-temperature environment. The present invention applies pulse current of the changing frequency to a battery, so that the internal resistance of the battery is energized to generate heat, thereby achieving the effect of low temperature self-heating inside the battery. Based on a second-order Thevenin equivalent circuit model, the internal parameters of the lithium ion power battery are constructed in combination with a recursive least-squares method and are identified; a three-dimensional state space method is used to establish a three-dimensional relationship among the internal parameters of the battery, the pulse current frequency andtemperature; and the change of the internal parameters of the battery at different temperatures and the pulse current frequency corresponding to the maximum internal resistance of the battery are calculated in real time. The alternating excitation low-temperature heating method is suitable for the technical field of charging of the batteries.
Owner:HARBIN UNIV OF SCI & TECH

Differential time domain spectroscopy method for measuring thin film dielectric properties

A non-contact, free-space method for determining the index of refraction of a thin film at a desired angular frequency. The method includes generating an input desired-frequency pulse and an optically detectable probe pulse. The thin film is moved in and out of the path of the input pulse, creating an output pulse that alternates between a transmitted signal, created when the film intercepts the input pulse path, and a reference signal, created when the sample is outside the input pulse path. The output pulse modulates the probe pulse, which is then detected with a photo detector, and the difference between the transmitted signal and the reference signal is calculated. The above steps are repeated over a plurality of delay times between the input pulse and the probe pulse until a complete field waveform of the differential signal is characterized. The index of refraction is calculated as a function of a ratio between the differential signal for the thin film and the reference signal. A complete field waveform of the reference signal may be characterized by repeating the above steps for a reference plate identical to the sample except having a non-transmissive film instead of the thin, transmissive film.
Owner:RENESSELAER POLYTECHNIC INST

Singularity-avoiding input parameter value space method for avoiding kinematic singularity in parallel mechanisms

The invention relates to a singularity-avoiding input parameter value space method for avoiding kinematic singularity in parallel mechanisms and belongs to technologies of avoiding parallel mechanisms kinematic singularity in the field of robotic mechanism. The method mainly includes: constructing parallel mechanism singularity position space distribution surfaces using input parameters as all coordinate axes; constructing inscribed envelope surface of the space distribution surfaces to obtain singularity-avoiding input parameter value space distribution surfaces; selecting proper operating points in the singularity-avoiding input parameter value space distribution surfaces, and determining the value ranges of input parameters meeting the operation requirements; determining the value ranges of the input parameters are in the singularity-avoiding input parameter value space distribution surfaces, and eliminating kinematic singularity in the parallel mechanisms during a design phase. The method is simple, universal and easy to implement; the method is directly applicable to eliminating kinematic singularity of operating space of the parallel mechanisms during the design phase and preventing the parallel mechanisms from running into a state of kinematic singularity during a control phase.
Owner:CHINA UNIV OF PETROLEUM (EAST CHINA)

Autonomous cooperation method of flexible connected double unmanned boats for oil spill roundup

The invention discloses a flexibly connected double unmanned ship autonomous collaboration method for rounding up oil spillage. The method comprises the steps of (1) planning a sailing trajectory capable of meeting multiple constraint conditions according to the oil spillage position, the initial positions of unmanned ships and dynamic characteristics of the flexibly connected unmanned ships; (2) performing trajectory tracking on the acquired sailing trajectory; (3) correcting the expected heading and speed of each unmanned ship in real time according to influences of a flexible connection acting force and force moment by adopting a fuzzy null space based behavior fusion method in order to ensure the unmanned ships to fulfill the task and reduce adverse influences of the flexible connection acting force and force moment in the process of performing trajectory tracking; and (4) calculating a control instruction by a motion controller of the unmanned ships so as to drive the actual heading and speed of the unmanned ships to reach the expected values. According to the invention, adverse influences generated by the flexible connection acting force and force moment are effectively eliminated by using the fuzzy null space method, and autonomous collaboration control for the flexibly connected double unmanned ship is realized.
Owner:HARBIN ENG UNIV

Radio frequency interference suppression method based on FRFT frequency estimation subspace

The invention provides a radio frequency interference suppression method based on an FRFT frequency estimation subspace. The method specifically comprises the steps of calculating an optimal order ofFRFT; calculating FRFT of a frame of original data under the optimal order through a kernel function, and obtaining an original signal of an FRFT frequency domain; detecting radio frequency interference of an FRFT frequency domain signal; if the radio frequency interference exists in the FRFT frequency domain signal, obtaining an FRFT time domain signal through inverse Fourier transform; constructing an orthogonal projection matrix by utilizing an FRFT frequency estimation subspace method, and performing projection transformation on the FRFT time domain signal to suppress the radio frequency interference; performing fast Fourier transformation to obtain the FRFT frequency domain signal after radio frequency interference suppression; and performing p-order inverse FRFT on the FRFT frequencydomain signal to obtain the original signal after radio frequency interference suppression. According to the method, steady-state and non-steady-state radio-frequency interferences can be suppressedat the same time; the integrity of useful signals can be kept on the basis of fully suppressing the radio frequency interferences; the effective detection distance of a radar is increased; and the precision of marine dynamics parameter inversion and target detection by the radar is improved.
Owner:WUHAN UNIV
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