378 results about "Reference wave" patented technology

The invention relates to an ultrasonic flow metering device and a metering method thereof, and relates to the field of ultrasonic measuring devices. According to the metering device, through a cross-correlation operation circuit, a microcontroller, a double-threshold comparator, a peak detector, a gain adjustment circuit and a head wave threshold adjustment circuit, self-adaptive processing and adjustment of echo signals and head wave thresholds are achieved, and the accuracy and reliability of flow metering are improved. The metering method adopts an adaptive adjustment strategy of echo signal amplifier gain based on an output signal of an echo signal peak detection circuit, and a head wave threshold adaptive adjustment strategy based on a correlation operation value of echo signal sampling data and pre-stored reference wave data. According to the scheme, the stability of the echo signal and the rationality of the head wave threshold value are guaranteed, the method has adaptability to echo contour feature changes caused by transducer aging or contamination, and then the reliability of the flow metering process is guaranteed.

The invention discloses a remote sensing image haze removal processing method and system, and relates to the technical field of image processing. The method comprises the steps of obtaining a to-be-processed remote sensing image; extracting wave band data of a plurality of wave bands in the remote sensing image to be processed, and determining a reference wave band and a plurality of target wave bands based on the wave band data; based on the reference wave band, determining an atmosphere illumination parameter, and calculating a transmittance distribution diagram of each target wave band; for each target wave band, carrying out haze removal processing on the target wave band according to the atmosphere illumination parameters and the transmittance distribution diagram to obtain an initial haze removal image of the target wave band; and performing fusion processing on the initial haze-removed images of the target wavebands to obtain a haze-removed image corresponding to the to-be-processed remote sensing image. By implementing the technical scheme provided by the invention, the effect of improving the accuracy of haze removal processing of the remote sensing image is achieved.

The invention discloses a high-precision methane infrared spectrogram intelligent detection method and system, and relates to the field of infrared spectrum determination.The method comprises the steps that multi-wavelength signals of a target detection area are collected, the change process of the multi-wavelength signals is continuously monitored, a change sequence of the wavelength signals is obtained, the change sequence is analyzed, and a methane infrared spectrogram is obtained. Obtaining a first time sequence characteristic of the main absorption wavelength signal relative to the first reference wavelength signal and a second time sequence characteristic of the main absorption wavelength signal relative to the second reference wavelength signal, and determining a judgment threshold according to real-time change states of the first reference wavelength signal and the second reference wavelength signal; and when the change of the main absorption wavelength signal is detected to be earlier than the change of any reference wavelength signal and the change amplitude of the main absorption wavelength signal is greater than a judgment threshold value, calculating the methane concentration value according to the change time difference and the change amplitude ratio of the main absorption wavelength signal and the reference wavelength signal. By implementing the method, the response time of methane leakage identification can be reduced.

The invention belongs to the technical field of mine safety monitoring and rock mass engineering detection, and particularly discloses a method for constructing a non-uniform wave velocity field model of an underground mine, which comprises the following steps: selecting a plurality of rock materials, manufacturing a plurality of regular blocks, measuring a reference wave velocity, manufacturing a rock test piece, and carrying out a wave velocity test experiment; a wave velocity quantification formula is constructed through fitting experiment data; constructing a three-dimensional block model according to the spatial features of the prediction area, dividing the three-dimensional block model into a plurality of block unit models, and generating a lithologic block unit model through spatial interpolation; and constructing a three-dimensional engineering geological representation model, extracting geological feature data in the three-dimensional engineering geological representation model, and performing wave velocity assignment on all lithologic block unit models by using a wave velocity quantification formula to obtain a three-dimensional non-uniform wave velocity field model. According to the method, the wave velocity field model better conforming to the actual condition of the underground mine can be constructed, the limitation of constant wave velocity assumption in a traditional model is overcome, and the reliability of micro-seismic monitoring is improved.

The invention provides a design method and a preparation method of a germanium substrate 2-5.9 [mu] m waveband cut-off 6.3-14 [mu] m high-transmittance optical filter film. The design method comprises the steps that 550 nm serves as a reference wavelength of 1 / 4 wavelength thickness of an optical thin film, 2.1 (L2HL) 10, 2.8 (L2HL) 10, 3.6 (L2HL) 9 and 4.5 (L2HL) 9 of a Sub / S1 face and 42 (L2HLKL) 3 and 59 (K2LK) 1AIR of a S2 face are used, Sub is a germanium substrate, AIR represents air, H represents Ge, L represents ZnSe, and K represents YbF3; 75 layers of an S1 surface and 12 layers of an S2 surface are generated, the S1 surface is bottomed ZnSe, the outermost ZnSe is adopted, middle Ge and ZnSe are alternated, and the S2 surface is Ge / ZnSe / Ge / ZnSe / Ge / ZnSe / YbF3 / ZnSe / Ge / ZnSe / YbF3 / ZnSe; optimizing to obtain the optimal film layer thickness; and inputting into a coating machine.

The invention relates to the technical field of data processing, and discloses a digital feedback dynamic adjustment method and system for a neutron generator control signal, and the method comprises the steps: calling a reconfigurable waveform parameter set corresponding to a target neutron from a mapping relation according to the yield and beam spot characteristic demands of the target neutron; generating a basic high-frequency pulse sequence of the neutron tube, and performing pre-distortion filtering on the basic high-frequency pulse sequence to obtain a high-frequency pulse sequence of the neutron tube; collecting an anode current and a target voltage signal of the neutron tube applied with the high-frequency pulse sequence during operation, and converting the anode current and the target voltage signal into a digital feedback current; comparing the digital feedback flow with a reference waveform in the reconfigurable waveform parameter set in real time to obtain an error correction amount of the high-frequency pulse sequence; dynamically adjusting the high-frequency pulse sequence according to the error correction; applying the dynamically adjusted high-frequency pulse sequence to a corresponding electrode in a neutron tube through power; the neutron tube control signal processing efficiency can be improved.

The invention relates to the technical field of converter control, in particular to a novel four-level efficient grid-connected system and a control method, and the method comprises the steps: determining the target output power, the target input power, the actual output power and the actual input power of a converter based on a 4L-HCC converter; determining a phase angle and an output voltage amplitude based on a preset virtual synchronous machine control strategy, and converting to obtain a corresponding three-phase reference voltage; performing HCC internal capacitor voltage control on the converter, establishing a corresponding loss function, and determining a reference wave change range corresponding to each switching device on the converter based on actual setting; the corresponding reference wave signal with the minimum loss function derivative is calculated; and carrying out phase shift pulse width modulation on the converter, taking high-frequency triangular waves with different phases as carriers, comparing the calculated reference wave signals with the carriers, calculating the duty ratio of each switching device of the converter and a switch driving signal, and driving each switching device of the converter.

The invention provides an isolating switch performance monitoring system, which comprises a data acquisition module which at least comprises a current sensor and a signal conditioning circuit and is used for acquiring action current signals of a driving motor in an isolating switch in real time; the data processing module is used for performing filtering, noise reduction and time domain and frequency domain feature extraction on the received action current signal of the driving motor and establishing a corresponding waveform database according to the extracted features, and the waveform database at least comprises a normal waveform database and an abnormal waveform database; and the state evaluation module is used for comparing the real-time waveform with the reference waveform in the waveform database through a preset algorithm, identifying abnormal feature points existing in the real-time waveform and generating a corresponding performance evaluation result. Precise evaluation of the performance of the isolating switch is realized based on the current waveform of the driving motor.

The invention provides a method, a system and equipment for monitoring trackside non-electric train wheel defects. The method comprises the following steps: filtering original wavelength data to obtain original smooth wavelength data; extracting an original vehicle passing waveform according to the original smooth wavelength data; carrying out normalization processing on the original vehicle passing waveform; and realizing wheel defect monitoring according to a corresponding relation between the reference waveform and the original vehicle passing waveform after normalization processing. Through detailed description of an automatic identification process of a defect waveform, rapid and accurate wheel tread defect detection is realized; on-line wheel health state monitoring can be achieved, train operation is not affected, and train transportation safety and efficiency are guaranteed. The accuracy of train wheel data extraction and the accuracy of wheel defect detection are guaranteed through an algorithm.

The invention provides a refuse landfill leakage detection method and system considering inhomogeneous medium stress wave propagation, and the method comprises the steps: building an inhomogeneous medium stress wave propagation model, and decomposing an actual wave velocity into a reference wave velocity and a variable quantity; estimating and updating the wave velocity in real time by adopting a self-adaptive algorithm; and finally, accurately positioning the position of the leakage source through a weighted optimization method. The invention also provides a system for realizing the method. The system comprises a sensor array, a signal acquisition and preprocessing module, a self-adaptive wave velocity estimation module, a leakage source positioning module and a result display and alarm module. According to the method, the non-uniformity and the time-varying characteristic of the medium are considered, the self-adaptive algorithm and the weighted optimization strategy are combined, the leakage point positioning precision is effectively improved, and the method has important practical value.

The invention provides a design method and a preparation method of a 1.8-4 [mu] m silicon-based lens anti-reflection film. The design method of the 1.8-4 [mu] m silicon-based lens anti-reflection film comprises the steps that Sa, a film system is designed with 550 nm as the reference wavelength of optical film design, a film stack formula Sub / 0.3 M 0.8 N (HL) 3K / AIR is used, the two faces of Sub are plated with the same film system, Sub is a silicon substrate, AIR represents air, in the film stack formula, H represents a high-refractive-index material ZnS with the 1 / 4 wavelength thickness, L represents a low-refractive-index material YbF3 with the 1 / 4 wavelength thickness, and in the film stack formula, Z represents a high-refractive-index material ZnS with the 1 / 4 wavelength thickness; m represents a base layer material SiO with the thickness of 1 / 4 wavelength, N represents a connecting layer material Ge with the thickness of 1 / 4 wavelength, K represents protective layer materials Al2O3 (aluminum oxide) and Sb with the thickness of 1 / 4 wavelength, and a film layer structure of Sub / SiO / Ge / ZnS / YbF3 / Al2O3 / Air is generated through an input film stack formula; sc, the thickness of the film layer is optimized through thin film design software, the optimal thickness of the film layer is obtained, and the transmittance of the 1.8-4-micron wave band of the optimized film layer structure meets the requirement; and Sd, the optimized film layer thickness is input into a control computer of the coating machine.

The invention relates to an anemia blood transfusion risk management system based on real-time monitoring, and belongs to the technical field of medical data processing. The management system comprises a plurality of sensors and is used for acquiring multiple monitoring data such as hemoglobin concentration, blood oxygen saturation waveform and cardiovascular waveform of a patient, and real-time analysis is executed by a calculation module. The calculation module quantifies key indexes such as blood volume change and hemoglobin concentration by constructing a dynamic risk index model, and performs morphological similarity comparison on a real-time waveform and a plurality of established reference waveform templates. And the management system corrects the risk level based on the similarity analysis result and outputs a comprehensive score. The score can be used as a reference standard for clinical blood transfusion intervention.

The invention discloses an intelligent distribution network nuclear phase method and system based on GPS clock synchronization, and relates to the field of power system distribution network operation and maintenance. The intelligent distribution network nuclear phase method and system based on GPS clock synchronization comprise a nuclear phase source reference unit, a non-contact nuclear phase terminal and a cloud server system. According to the intelligent distribution network nuclear phase method and system based on GPS clock synchronization, three-phase voltage waveforms are continuously collected through a nuclear phase source reference unit, and reference waves are formed through GPS clock synchronization, time label adding and cloud real-time synchronization; a non-contact phase checking terminal is used for collecting three-phase voltage waveforms of a measuring end, GPS clock synchronization, time label adding and data packaging are carried out and uploaded to a cloud end, then a cloud server system is used for intercepting the voltage waveforms of the same time period through a GPS clock to carry out phase checking and phase difference analysis, and then feedback signals are generated according to the analysis result and a phase difference threshold value. The single-person non-contact operation is realized, the safety is high, the precision is high, and the nuclear phase structure can be stored.

The invention relates to the technical field of stress testing, in particular to a VCSEL epitaxial wafer stress distribution monitoring method and system. The method comprises the following steps: acquiring a PL spectrum of each measurement point and a peak wavelength of the PL spectrum, and decomposing the PL spectrum into polarization components along a first crystal orientation and a second crystal orientation; obtaining the initial polarization orthogonality of the measurement point based on the peak intensity of the polarization component; obtaining a reference wavelength of the VCSEL epitaxial wafer, and calculating a thermally induced wavelength drift factor of a measurement point; based on the thermally induced wavelength drift factor and a set maximum saturation value, thermally induced polarization artifacts of the measurement points are calculated, the thermally induced polarization artifacts are in positive correlation with the thermally induced wavelength drift factor, and the maximum saturation value is taken as an upper limit; subtracting the thermally induced polarization artifact from the initial polarization orthogonality to obtain a pure stress index; the pure stress indexes are mapped to the corresponding coordinates, the stress distribution diagram of the VCSEL epitaxial wafer is obtained, and the accuracy of the stress distribution monitoring result of the VCSEL epitaxial wafer is effectively improved.

The invention relates to a measuring arrangement for the interferometric determination of the surface shape of a test object, wherein a test wave generated from electromagnetic radiation and reflected at the test object can be superimposed with a reference wave not reflected at the test object, with a reference element (110, 210, 310, 410) having a reference surface (112, 212, 312, 412) which, in the optical beam path, splits off the reference wave from the test wave before it strikes the test object (120, 220, 320, 420) by reflection, and at least one beam shaping surface (111, 211, 311, 411, 413, 414) located in the optical beam path in front of the reference surface, wherein this beam shaping surface is designed as an aspherical distortion correction surface such that a distortion occurring in a predetermined reference plane of the measuring arrangement is reduced. The invention further relates to a method for manufacturing an optical element for such a measuring arrangement.

The invention provides a design method and a preparation method of a 2-5.5 [mu] m high-transmittance film on a ZnSe substrate. The design method of the ZnSe substrate 2-5.5 [mu] m high-transmittance film comprises the following steps: Sa, film system design: 550 nm is used as a reference wavelength for optical film design, a film stack formula: Sub / 0.6 (LHL) 2MK / AIR is used, two sides of Sub are plated with the same film system, Sub is a ZnSe substrate, AIR represents air, in the film stack expression, H represents a high-refractive-index material ZnSe (zinc selenide) with the wavelength thickness of 1 / 4, L represents a low-refractive-index material YbF3 (ytterbium fluoride) with the wavelength thickness of 1 / 4, and the thickness of YbF3 is 1 / 4. K represents a protective layer material Al2O3 (aluminum oxide) with the wavelength thickness of 1 / 4, and M represents a connecting layer material Y2O3 (yttrium oxide) with the wavelength thickness of 1 / 4; sb, generating a film layer structure of Sub / YbF3 / ZnSe / YbF3 / ZnSe / YbF3 / Y2O3 / Al2O3 / Air according to an input film stack formula; sc, the thickness of the film layer is optimized through thin film design software, the optimal thickness of the film layer is obtained, and the transmittance of the optimized film layer structure at the wave band of 2-5.5 microns reaches the target; and Sd, inputting the optimized optimal film thickness into a control computer of the coating machine.

A method of controlling a reconfigurable intelligent surface (RIS) is provided for multi-target spot beamforming at a plurality of target beam focus positions. The RIS includes a 2D array of unit cells, each unit cell being controllable to be at any selected one of a plurality of wave propagation path states for providing a corresponding degree of phase shift for an incident electromagnetic wave irradiated thereon. The method includes: for each of the plurality of target beam focus positions: determining, for each unit cell of the plurality of the 2D array of unit cells, an interference pattern at the unit cell between a reference wave from a multi-mode orbital angular momentum (OAM) signal transmitter to the unit cell and an object wave from the target beam focus position to the unit cell, the multi-mode OAM signal transmitter being configured to generate and transmit a multi-mode OAM signal to irradiate the RIS at a surface thereof; and for each unit cell of the plurality of the 2D array of unit cells: determining a holograph pattern based on the interference patterns determined at the unit cell for the plurality of target beam focus positions; determining a degree of phase shift for the unit cell to provide based on the holograph pattern determined for the unit cell; and controlling the unit cell to be at a selected one of the plurality of wave propagation path states corresponding to the degree of phase shift determined for the unit cell to provide. There is also provided a corresponding RIS controller and a corresponding multi-target spot beamforming system.

The invention provides a communication perception integrated waveform design method for the Internet of Vehicles, which belongs to the technical field of wireless communication, and can realize peak performance, enhance radar capability and ensure efficient communication by minimizing the weight sum of multi-user interference, the similarity between a design waveform and a reference waveform, a Cramer-Rao bound and an ISAC waveform. According to the method, optimization with the total transmission power and the peak-to-average power ratio as constraints is adopted, a non-convex problem is converted into a convex problem, an alternating direction multiplier method algorithm is adopted for solving, and a simulation result shows that the ISAC waveform has good communication and target detection capability, and the V2X spectrum utilization rate can be improved. According to the method, a target can be detected during communication with a downlink user, the sum of MUI, CRB and waveform similarity is minimized, weighing parameters are introduced, flexible weighing between communication and sensing is achieved under the constraint of the total power and the peak-to-average power ratio, the method better adapts to a V2X high-dynamic scene, and mutual interference caused by separation of traditional sensing and communication functions is reduced.

A semiconductor driving device according to the present disclosure includes: a timing generation unit which generates gate ON reference signals respectively for a plurality of gate terminals; a gate reference waveform generation unit which generates a first gate reference waveform and a second gate reference waveform on the basis of the gate ON reference signals, and controls the first gate reference waveform and the second gate reference waveform in shifting from a non-conductive state to a conductive state of a multi-gate semiconductor switching element and shifting from a conductive state to a non-conductive state of the multi-gate semiconductor switching element; and a signal amplification unit which receives, as an input waveform, the first gate reference waveform and the second gate reference waveform, and amplifies the input waveform so that an output waveform follows the input waveform.

The invention discloses a high-resolution surface shape detection device of an off-axis wedge-shaped lens. The detection device mainly comprises a dynamic interferometer, a spherical lens, a standard reflector, an auto-collimation collimator and a standard wedge block. According to the invention, the standard wedge block is matched with the collimator to complete optical path calibration, and the dynamic interferometer is used to detect transmission wave surface error data of the off-axis wedge-shaped lens. In the measuring light path, the dynamic interferometer is placed towards the center of the off-axis wedge-shaped lens to be measured, and the wave surface to be measured and the reference wave surface can generate interference fringes on the whole target surface of the dynamic interferometer, so that the target surface pixels of the interferometer can be fully utilized, and the detection spatial resolution is improved. Wave surface PSD and GRMS values can be calculated by using measured wave surface error data, and an off-axis amount and a rear intercept of the off-axis wedge-shaped lens can be measured by using a laser range finder. The method can be used for multi-parameter high-resolution detection of the off-axis wedge-shaped lens, and is particularly suitable for high-precision off-axis wedge-shaped lens PSD2 detection, and the measurement result can be used for inspecting the product quality or correcting the processing error.

A high-speed switching N-bit path selection type silicon-based integrated microwave photon delay line comprises a wavelength tunable external cavity laser, an electro-optical modulator, an N-bit wavelength selection delay line and a photoelectric detector, and the wavelength selection delay line is composed of N + 1 2 * 2 wavelength interleavers and N groups of delay and reference waveguide pairs. After being modulated by a microwave signal, light output by the external cavity laser is input into the N-bit wavelength selection delay line and finally converted into a microwave signal through the photoelectric detector to be output. By switching the wavelength of the laser, high-speed switching of a delay light path can be realized, and then high-speed phase shifting of a microwave signal is realized. According to the scheme, the wavelength selection type delay line adopts a passive device design, and compared with a traditional optical switch type delay line, the wavelength selection type delay line is easy to realize low loss, does not need voltage regulation and control, and is low in overall system power consumption.

Provided are a method for operating a device in a wireless communication system, and a device using the method. The method comprises: measuring a plurality of reference beams; selecting at least one beam from among the plurality of reference beams; and communicating with a base station using the at least one selected beam, wherein the plurality of reference beams are beams transmitted according to a first scheme or a second scheme. In the first scheme, N (N is a natural number greater than or equal to two) reference beams are transmitted at a first transmission time, and an offset is applied to the N reference beams at a second transmission time. In the second scheme, 2N reference beams are transmitted, wherein a second frequency interval between adjacent beams of the 2N reference beams is half a first frequency interval between adjacent beams of the N reference beams.

The invention discloses a conventional direct current line single-ended protection method and system based on dynamic time curling, and the method comprises the steps: 1, obtaining the positive and negative electrode voltages of a direct current transmission line, calculating the line mode voltage and the wavelet transformation modulus maximum value of the line mode voltage, and entering a step 2 when the maximum value meets a protection starting criterion; step 2, calculating the maximum value of the absolute value of the voltage change rate of the positive and negative voltage fault components in a preset time window, if the absolute value is greater than a short-distance fault auxiliary criterion threshold, entering step 5, otherwise, entering step 3; 3, calculating a line mode voltage fault component time sequence; 4, calculating a dynamic time curl distance characteristic quantity between the normalized line mode voltage fault component time sequence and the reference waveform time sequence, when the dynamic time curl distance characteristic quantity is smaller than or equal to a fault section identification judgment threshold value, entering the step 5, and otherwise, returning to the step 1; and 5, judging a fault type and a line, and determining a restart control scheme. According to the invention, the problem that the traveling wave protection far-end high-resistance fault is easy to reject operation is solved.

The invention relates to an interferometric testing arrangement for testing the surface shape of a test object, comprising a lighting device (105, 205, 305) for generating an input wave from electromagnetic radiation produced by a light source and an interferometer (150) in which, after splitting the input wave into at least one test wave directed towards the test object (170) and a reference wave, testing the surface shape of at least a partial surface of the test object (170) can be carried out by interferometric superposition of the at least one test wave and the reference wave, wherein a diffuser (130, 230, 330) is arranged in the lighting device, wherein the lighting device has a first optical path (110, 210, 310) and a separate second optical path (120, 220, 320), and wherein the input wave is transmitted via both the first optical path (110, 210, 310) and the second optical path (120, 220, 320). 220,320) can be coupled into the interferometer (150).

The embodiment of the invention provides a wave surface information extraction method and device, electronic equipment and a storage medium, and belongs to the technical field of wave measurement. The method comprises the following steps: acquiring a liquid level image and a wave surface image, performing liquid level identification on the liquid level image to obtain a liquid level curve coordinate, and calculating reference wave height data of a liquid level curve; and performing identification to obtain original wave surface point cloud coordinates of the wave surface image, and performing coordinate system conversion on the plurality of original wave surface point cloud coordinates according to the conversion matrix to obtain a plurality of basic wave surface point cloud coordinates. And performing data calculation according to the target point cloud coordinate, the reference point cloud coordinate and the reference wave height data to obtain target wave height data corresponding to the target detection point, and generating wave surface information of the target detection point based on the target wave height data. According to the embodiment of the invention, the wave surface information acquisition efficiency can be improved, and the cost is reduced.

The invention relates to the technical field of cascade energy storage system control, in particular to an energy storage array control method with an island operation function and a related device, and the method comprises the steps: obtaining the active power and reactive power of operation of each cascade energy storage unit, and calculating an active current component and a reactive current component; according to the active current component and the reactive current component, respectively calculating an overall phase reference value and a voltage amplitude reference value of the energy storage array, and respectively generating a phase angle reference value and a voltage amplitude reference value of each cascaded energy storage unit; and according to the phase angle reference value and the voltage amplitude reference value of each cascaded energy storage unit, generating a three-phase voltage reference wave of each cascaded energy storage unit, and performing SOC balance control and carrier phase shift modulation on the voltage reference wave to generate a converter valve trigger pulse. According to the method, the control synchronism among the cascade energy storage units is ensured, and the stability of island operation is enhanced. The problem that in the prior art, when all cascade energy storage units operate in an isolated island mode, the instability risk exists is solved.

The invention discloses a multi-converter independent networking control method, and belongs to the technical field of converter control, and the method comprises the steps: determining the output frequency of a converter based on a networking control active link; determining the internal potential of the converter based on the network construction control reactive link; determining a current instruction value through the virtual impedance link based on the grid-connected point voltage, the output frequency of the current converter and the internal potential of the current converter; and the current controller determines a three-phase reference wave based on the output frequency of the current converter and the current instruction value, and the three-phase reference wave is used for realizing coordinated operation among the current converters without depending on communication when the plurality of current converters operate in parallel. According to the method, the internal potential and the frequency output by the network construction control link are converted into the reference values of the current controller by using the virtual impedance, and the method is used for realizing coordinated operation among the converters without depending on communication when multiple converters run in parallel.

The invention provides a dynamic gesture recognition method and device, electronic equipment, a chip and a medium, and relates to the technical field of man-machine interaction. The method comprises the following steps: carrying out key point identification on an image in a video frame collected by a binocular camera, and respectively determining a first three-dimensional key point and a second three-dimensional key point; identifying the gesture category of the target gesture in the video frame as a first gesture category by using a dynamic gesture classification model; based on the corresponding relation between the reference waveform feature and the gesture category, using a signal recognition algorithm to analyze the waveform feature formed by the first stereo key point and / or the second stereo key point, and recognizing a second gesture category corresponding to the target gesture in the video frame; and checking whether the first gesture category is consistent with the second gesture category to determine a target gesture category. Through the technical scheme provided by the invention, the problems of low accuracy and low stability of dynamic gesture recognition are solved, the accuracy and the stability of gesture recognition are improved, and the user experience of gesture interaction is improved.

The invention discloses a free-form surface imaging aberration propagation calculation and aberration control method. According to the method, on the basis of a given system light path, an object plane, an image plane, an entrance pupil and an exit pupil of each optical curved surface are calculated, and reference wave surfaces of a central view field at the entrance pupil and the exit pupil are calculated. A group of characteristic light is generated by an entrance pupil and a field of view of the sampling system, the optical path difference of the characteristic light of each field of view propagating from the entrance pupil of each curved surface to the exit pupil relative to the main light is calculated, and the aberration field of each curved surface is obtained by fitting the optical path difference of the full field of view; determining the contribution of each curved surface to the dominant aberration according to the dominant aberration of the current system and the aberration field of each curved surface, thereby determining the curved surface which is optimized first; the aberration is reduced by optimizing the curved surface parameters, corresponding to the current dominant aberration, of the curved surface, and the process is repeated until the design meets the requirements. The method can effectively guide the optimization of the free-form surface imaging system, reduces the deviation degree of the free-form surface while guaranteeing the imaging performance, and effectively reduces the processing and detection difficulty of the surface.

The invention relates to a method for interferometric surface measurement of a test specimen, a computer-generated hologram (CGH) and an interferometric test arrangement. In a method according to the invention, an interferometric superposition of a test wave directed by a CGH (120, 220, 320, 410, 420, 430, 510) onto the test piece (140, 240, 340, 540) and reflected therefrom is carried out with a reference wave not reflected at the test piece, wherein, based on a further interferometric superposition of light reflected at at least one Littrow structure (122, 222, 322, 412, 422, 432, 512) of the CGH with light reflected at a reference surface, a contribution to the optical effect of the CGH caused by a deformation present at the CGH is determined, and wherein a determination of the fit of the test piece (140, 240, 340, 540) is carried out taking this contribution into account.