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1506 results about "Narrow band" patented technology

Generally, narrowband describes telecommunication that carries voice information in a narrow band of frequencies. More specifically, the term has been used to describe a specific frequency range set aside by the U.S. FCC for mobile or radio services, including paging systems, from 50 cps to 64 Kbps.

Energy harvesting acoustic metasurface using piezoelectric transducers

The technology described herein is directed towards resonators that incorporate or are closely coupled to transducers from which energy is harvested. The resonators can be unit cells of a metasurface configured for narrowband sound absorption by phase cancellation of the acoustic wave Electroacoustic transducers such as piezoelectric transducers can be positioned, e.g., at the neck ports of the resonators, to generate electricity as the air pressure of incoming acoustic waves enters the unit cells. Energy can be harvested from the electricity, and stored for usage and / or used directly to power a device. Such a device powered by the harvested energy can change the resonant frequency of the device, e.g., by changing temperatures in the resonators' air cavities, changing respective dimensions of the respective air cavities, or changing the resonant frequency of the unit cells resonators by changing respective airflow in the respective air cavities.
Owner:DELL PROD LP

Passive metamaterials-based acoustic sound suppression modules for servers

The technology described herein is directed towards one or more modular metasurfaces arranged with unit cells for sound absorption, in which the unit cells are based on Helmholtz resonators that are deployed proximate to a server, without substantially obstructing airflow from the server fan(s). Each sound absorbing unit-cells is designed and constructed based on a specific resonance frequency, and includes a neck portion and air chamber dimensioned to resonate at the desired resonance frequency and thereby inverse phase cancel corresponding narrowband frequencies of incoming sound waves. The metasurfaces can be arranged in a modular frame structure of surrounding unit cells, positioned behind the server's fan(s), with an opening in the frame structure to facilitate airflow therethrough, without obstructing or substantially obstructing the airflow to the surrounding environment.
Owner:DELL PROD LP

Wideband / multiband add-on metasurface modules for enhanced noise suppression in server infrastructure

The technology described herein is directed towards modular metasurfaces arranged with unit cells for narrowband, wideband and / or multiband sound absorption, in which the unit cells are based on Helmholtz resonators that are deployed in a server rack, proximate to a server, without substantially obstructing airflow from the server fan(s). Each sound absorbing unit-cells is designed and constructed based on a specific resonance frequency, and includes a neck portion and air chamber dimensioned to resonate at the desired resonance frequency and thereby inverse phase cancel corresponding narrowband frequencies of incoming sound waves. Differently-dimensioned unit cells can be built into a single metasurface module, thereby facilitating wideband and / or multiband sound absorption with that metasurface. The modular metasurfaces can be attached to the sidewalls of a server rack, or positioned in otherwise empty slots above and below a server, optionally coupled to blanking panels for covering the openings of those slots.
Owner:DELL PROD LP

Multi-source fusion spectrum cross-domain high-precision prediction method and system based on transfer learning

The invention provides a multi-source fusion spectrum cross-domain high-precision prediction method and system based on transfer learning. The method comprises the following steps: S1, acquiring spectrograms collected by a spectral imaging device under multiple wavelengths; s2, extracting various types of features from the spectrogram; s3, training a fusion model to obtain a trained fusion model; and S4, inputting a to-be-predicted spectrum into the trained fusion model, and outputting a result. According to the invention, 10 <-4 > nm-level wavelength prediction can be achieved in a common industrial camera system, and the level of a scientific research-level grating spectrometer (0.001-0.002 nm) can be reached / exceeded; on a narrow-band, middle-band and wide-band multi-scene cross-domain data set, the mean absolute error (MAE) can be reduced from the nanoscale to the magnitude of 10 <-4 > nm, and excellent robustness is kept under the conditions of noise, feature deficiency and few samples.
Owner:HONG KONG UNIV OF SCI & TECH (GUANGZHOU)

Method for establishing grassland plant nitrogen content monitoring model based on remote sensing technology

The invention relates to the technical field of leaf nitrogen content estimation, in particular to a method for establishing a grassland plant nitrogen content monitoring model based on a remote sensing technology. The method comprises the following steps: controlling an unmanned aerial vehicle platform carrying a narrowband multispectral camera and a linear polarization camera, and collecting a spectral image sequence and a polarization image group at an observation window with a solar zenith angle of 30-40 degrees; extracting a reflectivity value of each wave band in the spectral image sequence, calculating a reflectivity first-order derivative and determining a red edge position offset; extracting horizontal and vertical polarization components in the polarization image group, calculating a polarization degree and constructing a polarization degree difference index; and identifying the center of the fecal spot by searching a pixel with a local maximum polarization degree difference index and red edge position offset blue shift exceeding a preset threshold value. According to the method, excrement spot recognition and remote sensing description of the nitrogen influence range thereof are achieved through double-index complementation of the red edge position offset and the polarization degree difference index.
Owner:河套学院

Cable fault diagnosis method, system and terminal

The invention relates to the technical field of fault diagnosis, and discloses a cable fault diagnosis method, system and terminal, and the method comprises the steps: applying a broadband excitation signal to a target cable, so as to excite the target cable to generate a first response signal; extracting multi-dimensional time-frequency features of the first response signal after adaptive wavelet threshold denoising, and matching a fault template of a preset cable reference model according to energy distribution features in the multi-dimensional time-frequency features; determining a fault area in a fault template corresponding to the target cable according to the propagation time and the propagation speed of the first response signal; applying the narrowband excitation signal to a fault area of the target cable to obtain an impedance spectrum; the resonant frequency point based on the impedance frequency spectrum and the corresponding impedance amplitude value are compared with a typical fault mode in a fault feature database, and the fault type and the fault position of the target cable are obtained; generating a diagnosis report of the target cable according to the fault type and the fault position; the cable fault diagnosis accuracy can be improved.
Owner:HANGZHOU JUQI INFORMATION TECH CO LTD +2

Solid waste-based zinc chloride preparation process control method and system

The invention discloses a solid waste-based zinc chloride preparation process control method and system, and relates to the technical field of zinc chloride preparation, and the method comprises the following steps: obtaining a unified time base line, establishing a bubble phase reference field, collecting a sound-induced echo sequence, a micro-pressure waveform sequence and a light scattering sequence of a reaction liquid under the bubble phase reference field, and calculating the solid waste-based zinc chloride preparation process. Fusing to generate a bubble density space-time matrix; and performing reversible time-frequency rearrangement based on the bubble density space-time matrix, decomposing to obtain different frequency band distributions, extracting a narrow-band resident bubble group, calculating critical volume distribution and collapse precursor indexes, and constructing a dynamic risk fingerprint database. According to the method, a unified time base line and a bubble phase reference field are constructed, the bubble state is perceived in real time, collapse forebodes are recognized, a dynamic risk fingerprint database is established, directional intervention and reverse energy channel collapse nucleus extinguishing are achieved in combination with an energy aggregation node, finally closed-loop regulation is constructed through calibration write-back, the safety and stability of zinc chloride preparation are improved, and the method is suitable for large-scale popularization and application. And efficient utilization and clean production of solid waste are promoted.
Owner:TIANJIN YOUFA DEZHONG STEEL PIPES CO LTD

Acoustic metasurface with aperture switching modularity

The technology described herein is directed towards a metasurface arranged with unit cells for narrowband sound absorption, in which the unit cells are based on Helmholtz resonators that can have their resonant frequencies selected via interchangeable portions. A sound absorbing unit cell is designed and constructed in two parts based on a desired resonance frequency, such as a neck portion and air chamber portion. The portions are dimensioned such that when coupled together, Helmholtz resonators are formed that resonate at a desired resonance frequency and thereby inverse phase cancel corresponding narrowband frequencies of incoming sound waves. A portion with different dimensions can be interchanged to adjust the resonant frequencies to cancel acoustic waves of different frequencies corresponding to noise, which can change over time. The unit cells can be distributed as part of a metasurface, which can be positioned proximate to a noise source to phase cancel the noise.
Owner:DELL PROD LP

Calibration device with spectrum self-calibration function and high-resolution spectrum calibration method thereof

The invention discloses a calibration device with a spectrum self-calibration function and a high-resolution spectrum calibration method thereof. The device comprises a narrow-band light source, a broadband light source, an optical fiber isolator, a coupler, an interference system, a multi-way switch, an FP (Fabry-Perot) cavity, a collimator, an orthogonal dispersion system and a computer, wherein the orthogonal dispersion system consists of a cylindrical lens, a reflector, a virtual phase array, a grating, a focusing lens and an industrial camera; according to the device, different light source paths are gated, FP cavity modulation and orthogonal dispersion system light splitting are utilized, and an industrial camera is combined to receive light signals. According to the method, the mapping relation between pixels and wavelengths can be established, the two-dimensional spectrum is compressed into the one-dimensional calibration spectrum through light intensity modulation and normalization processing, the calibration process of the orthogonal dispersion system is simplified, and the measurement precision is improved; and system drift can be compensated in real time through self-checking calibration, and the reliability of a measurement result is ensured, so that accurate calibration and measurement of a high-resolution spectrum can be realized.
Owner:HEFEI UNIV OF TECH

Multi-function bimorph microelectromechanical systems integration (MEMS) for analog tunability in metasurfaces

The technology described herein is directed towards a metasurface arranged with unit cells for narrowband sound absorption, in which the unit cells are based on Helmholtz resonators that can have their resonant frequencies adjusted via MEMS actuators. A sound absorbing unit-cell is designed and constructed based on a general resonance frequency, and includes a neck portion and air chamber dimensioned to resonate close to the desired resonance frequency and thereby inverse phase cancel corresponding narrowband frequencies of incoming sound waves. A bimorph MEMS actuator and / or moveable part in the resonators, controlled by a controller, facilitates changing of the airflow the unit cells to adjust the resonant frequencies thereof, to cancel acoustic waves of different frequencies corresponding to noise, which can change over time. The unit cells can be distributed as part of a metasurface, which can be positioned proximate to a noise source to phase cancel the noise.
Owner:DELL PROD LP

Antenna unit radiator, circularly polarized phased-array antenna unit and antenna array

The invention discloses an antenna unit radiator, a circularly polarized phased-array antenna unit and an antenna array, and belongs to the technical field of antennas. The circularly polarized phased-array antenna unit comprises an antenna unit radiator, a first dielectric layer, a metal patch, a second dielectric layer, a third dielectric layer and a metal ground layer which are arranged in sequence; two L-shaped microstrip probes which are orthogonally arranged are laid on the top of the third dielectric layer; the third dielectric layer is internally provided with feed metal columns in one-to-one correspondence with the L-shaped microstrip probes, the top ends of the feed metal columns are connected with the corresponding L-shaped microstrip probes, and the bottom ends of the feed metal columns are provided with feed ports. The antenna array is formed by the antenna unit array. The working bandwidth of the antenna can be expanded, the defect of the narrow-band characteristic of the microstrip antenna is overcome, the degree of freedom of design of the phased-array antenna is improved, impedance matching is facilitated, and the circular polarization performance of the phased-array antenna array is greatly improved.
Owner:CHINA STARWIN SCI & TECH CO LTD

Reconfigurable acoustic metasurface using a shared tuning element for cavity volume change

The technology described herein is directed towards a metasurface arranged with unit cells for narrowband sound absorption, in which the unit cells are based on Helmholtz resonators that can have their resonant frequencies adjusted via a shared tuning element, e.g., a screw, or a piezoelectric actuator. A sound absorbing unit-cell is designed and constructed based on a general resonance frequency, and includes a neck portion and air chamber dimensioned to resonate close to the desired resonance frequency and thereby inverse phase cancel corresponding narrowband frequencies of incoming sound waves. Collectively moveable floors in the resonators facilitate changing the resonators' air cavity dimensions, to adjust the resonant frequencies to cancel acoustic waves of different frequencies corresponding to noise, which can change over time. The unit cells can be distributed as part of a metasurface, which can be positioned proximate to a noise source to phase cancel the noise.
Owner:DELL PROD LP

Multi-network convergence gateway system supporting satellite, cellular and wide-narrow band ad hoc networks

The invention relates to a multi-network convergence gateway system supporting a satellite, a cellular and a wide-narrow band ad hoc network, and the system comprises a satellite communication module which is used for carrying out the communication connection with a satellite, and receiving and transmitting a satellite signal; the cellular communication module is used for communicating with a cellular network base station; the wide-narrow band ad hoc network module is used for constructing an ad hoc network in a local area to realize communication between nodes; the data processing module is used for uniformly processing data from the satellite communication module, the cellular communication module and the wide-narrow band ad hoc network module; and the power management module is used for managing and controlling a power supply of the whole system. The method has the beneficial effects that fusion of various communication networks can be realized, communication requirements in different scenes are met, and the power consumption of the system is reduced.
Owner:JIANGSU LEZHONG INFORMATION TECH CO LTD

Acoustic metasurface with integrated actuators for tuning the cavity volume

The technology described herein is directed towards a metasurface arranged with unit cells for narrowband sound absorption, in which the unit cells are based on Helmholtz resonators that can have their resonant frequencies adjusted via actuators, e.g., piezoelectric motors. A sound absorbing unit-cell is designed and constructed based on a general resonance frequency, and includes a neck portion and air chamber dimensioned to resonate close to the desired resonance frequency and thereby inverse phase cancel corresponding narrowband frequencies of incoming sound waves. Moveable partitions in the resonators, controlled by piezoelectric actuators, facilitates changing of the resonators' air cavity dimensions, to adjust the resonant frequencies to cancel acoustic waves of different frequencies corresponding to noise, which can change over time. The unit cells can be distributed as part of a metasurface, which can be positioned proximate to a noise source to phase cancel the noise.
Owner:DELL PROD LP

Narrowband reflective optical combiner with narrowband display device having multi-coloured backlight unit

A display device includes a backlight unit that is controllable to switch between lights of different colours having specific wavelengths, and an active panel including a liquid crystal (LC) layer. A multi-band reflective coating on an optical combiner is configured to selectively reflect the lights having the specific wavelengths. Different sets of drive signals are generated for different sub-images of an image. LC cells of the LC layer are controlled individually using the different sets of drive signals according to a predefined sequence in which the sub-images are to be displayed, whilst controlling the backlight unit to switch between lights of different colours according to the predefined sequence, thereby producing a synthetic light field corresponding to the image. The optical combiner is employed to selectively reflect the synthetic light field towards eyes of user(s), whilst optically combining a real-world light field with the synthetic light field.
Owner:DISTANCE TECHNOLOGIES OY

Underwater DOA estimation method based on graph nerve and convolutional neural network

The invention relates to the field of underwater sound signal processing, in particular to an underwater DOA (direction of arrival) estimation method based on graph nerves and a convolutional neural network, which comprises the following steps: 1, establishing a linear array, and enabling narrow-band signals to simultaneously reach an underwater sound array; 2, performing signal preprocessing to obtain a signal covariance matrix, and performing normalization processing; 3, extracting correlation between array elements and spatial features of array signals, and performing data supplementation on sparse linear array information; 4, forming a double-branch structure, enhancing the information aggregation capability, and extracting features from a space path and a time domain path; and 5, constructing an adjacent matrix, filling node features of damaged array elements, adopting a double-branch structure, extracting spatial features and time domain features, carrying out feature integration, and outputting a DOA estimation result. The spatial correlation between array elements is extracted and the array sparsity problem is processed by using the graph neural network, and the time domain features of the signals are extracted in combination with the convolutional neural network, so that more accurate and more robust DOA estimation can be realized under the conditions of low signal-to-noise ratio and array sparsity.
Owner:QINGDAO UNIV OF SCI & TECH

Full-perovskite laminated solar cell based on narrow-band gap buried interface modification and preparation method and application of full-perovskite laminated solar cell

The invention discloses a full-perovskite laminated solar cell based on narrow-band-gap buried interface modification and a preparation method and application of the full-perovskite laminated solar cell. According to the preparation method of the full-perovskite laminated solar cell based on narrow-band-gap buried interface modification, hydrazine sulfate and lead iodide are introduced to serve as an interface modification layer between a narrow-band-gap perovskite layer and a hole transport layer, and through the synergistic effect of the hydrazine sulfate and the lead iodide, surface defects of the hole transport layer can be effectively passivated; moreover, the hole mobility can be improved remarkably, and the photoelectric conversion efficiency of the cell is improved based on the preparation method of the full-perovskite laminated solar cell. The full-perovskite laminated solar cell has high photovoltaic performance and can be widely applied to the photoelectric field.
Owner:NANJING TECH UNIV

Semiconductor etching end point detection method and multi-channel detection system

The invention discloses a semiconductor etching end point detection method and a multi-channel detection system, and the detection method comprises the following steps: outputting detection light; expanding the detection light into a continuous spectrum band; imaging the continuous spectral band to a modulation surface of a digital micromirror device, and establishing a pixel group corresponding to each narrow-band wavelength of the continuous spectral band; performing spatial sampling on the continuous spectrum band, and distributing and writing a unique radio frequency modulation frequency f for each pixel group; respectively executing vibration type switch modulation on each pixel group at a radio frequency modulation frequency f so as to convert wavelength information of a continuous spectrum band into a time domain frequency optical signal; converting the time domain frequency optical signal into a time domain electric signal; performing frequency domain analysis on the time domain electric signal, and demodulating gas absorption light intensity corresponding to each modulation frequency; and judging the etching end point of the semiconductor according to the change trend of the gas absorption light intensity. According to the invention, parallel detection of a plurality of spectrum channels can be realized through a single detector so as to judge an etching end point.
Owner:SHANGHAI CHEYITIAN TECH CO LTD

Flow field data modal decomposition method, device and equipment suitable for non-stationary flow field of aircraft and storage medium

ActiveCN121935591AFlight vehicleField data
The invention discloses a flow field data modal decomposition method, device and equipment suitable for a non-stationary flow field of an aircraft, and a storage medium, and relates to the technical field of hydrodynamics, and the method comprises the steps: obtaining the spatial-temporal data of the non-stationary flow field of the aircraft, determining a physical representation form, and obtaining the spatial-temporal data of the non-stationary flow field of the aircraft; the method comprises the following steps of: decomposing a plurality of low-order dynamic process components consisting of spatial modals and time evolution coefficients by utilizing a frequency modulation technology, constructing a frequency modulation operator, converting the time evolution coefficient of each component into a narrowband frequency modulation component time sequence signal, and optimizing the narrowband signal bandwidth by taking minimization of the narrowband signal bandwidth as an optimization target; and constructing a to-be-solved variational optimization problem by combining the flow field reconstruction constraint and the frequency modulation structure constraint. According to the method, a time evolution coefficient, an instantaneous frequency, an instantaneous amplitude and a spatial mode are obtained through iterative solution by adopting an alternating direction multiplier method, and a modal decomposition result is determined based on a solution result, so that adaptive extraction and dynamic characteristic description of the non-stationary flow field are realized, and the modal separation precision and the extraction efficiency of nonlinear and transient characteristics of the non-stationary flow field are improved.
Owner:CALCULATION AERODYNAMICS INST CHINA AERODYNAMICS RES & DEV CENT

Reconfigurable acoustic surface using microelectromechanical systems (MEMS) actuators for changing cavity resonance

The technology described herein is directed towards a metasurface arranged with unit cells for narrowband sound absorption, in which the unit cells are based on Helmholtz resonators that can have their resonant frequencies adjusted via MEMS actuators. A sound absorbing unit-cell is designed and constructed based on a general resonance frequency, and includes a neck portion and air chamber dimensioned to resonate close to the desired resonance frequency and thereby inverse phase cancel corresponding narrowband frequencies of incoming sound waves. A moveable partition in the resonators, controlled by MEMS actuators, facilitates changing of the resonators' air cavity dimensions, to adjust the resonant frequencies to cancel acoustic waves of different frequencies corresponding to noise, which can change over time. The unit cells can be distributed as part of a metasurface, which can be positioned proximate to a noise source to phase cancel the noise.
Owner:DELL PROD LP

Narrowband interference filtering method and device based on HPLC (High Performance Liquid Chromatography) chip

The invention relates to a narrow-band interference filtering method and device based on an HPLC (High Performance Liquid Chromatography) chip, and belongs to the technical field of power line carrier communication. When pulse processing is carried out on a signal, AGC / DAGC processing is paused if a narrowband interference detection starting signal is detected, a narrowband interference detection module calculates a narrowband interference frequency point by using the signal of which the AGC / DAGC processing is paused, and a filter coefficient used by a narrowband interference elimination module is determined based on the narrowband interference frequency point; and the narrowband interference elimination module carries out narrowband interference elimination processing according to the determined filter coefficient. Wherein the AGC / DAGC processed signal is paused when the signal participating in the calculation of the narrowband interference frequency point is subjected to pulse processing, so that signal fluctuation caused by AGC / DAGC processing is avoided, the calculation accuracy of the narrowband interference frequency point is improved, and the narrowband interference filtering effect is ensured.
Owner:SPL ELECTRONICS TECH CO LTD

Multi-spectral imaging system and method for conduits

A method of imaging an internal surface of a conduit, the method including deploying an inspection assembly within an internal volume of a conduit, the inspection assembly having a camera and a lighting array including a plurality of light emitters; illuminating a region of interest on said internal surface using the lighting array; and capturing image data of the region of interest using the camera, the image data including spatial data and intensity data at a plurality of different narrowband wavelength ranges of light.
Owner:E V OFFSHORE LTD

Multi-mode consistency load rolling prediction method and system

The invention discloses a multi-mode consistency load rolling prediction method and system, and the method comprises the steps: carrying out the variational mode decomposition of an original load sequence, and generating K narrowband components; specifying a target component in the K narrowband components, dividing the rest components into a low-side band set and a high-side band set according to frequencies, and aggregating the low-side band set and the high-side band set to obtain a context component; performing multi-scale convolution residual encoding on the target component through a multimode frequency band alignment encoder, superposing a multimode consistency regularization constraint, inhibiting frequency band drift, and outputting target representation; based on the target representation, dynamically quantifying contribution weight of a context component to a target component through a multi-head cross-attention mechanism, and generating condition enhancement features in combination with gating residual injection; on the basis of conditional enhancement features, a peak inflection point is captured by adopting local short convolution, cross-day correlation is modeled through global self-attention, and a predicted value of a narrow-band component is output; and splicing the predicted values of all the narrowband components according to the dynamic weight to obtain a final load prediction result.
Owner:STATE GRID CORPORATION OF CHINA +4

Multi-shafting rotating machine rotating speed estimation method based on displacement vibration signals

The invention belongs to the technical field of rotating machinery signal processing, and discloses a multi-shafting rotating machinery rotating speed estimation method based on a displacement vibration signal, and the method comprises the steps: collecting the displacement vibration signal, and carrying out the short-time Fourier transform to obtain a time-frequency distribution matrix; screening out a safety harmonic set of each shafting based on the estimated rotating speed range; calculating a definition evaluation value of each safety harmonic wave and selecting an optimal harmonic wave as a target tracking harmonic wave; constructing a cost function fusing amplitude and frequency abrupt change penalty, and performing ridge line tracking in the local time-frequency matrix after noise reduction to obtain a preliminary estimation time-frequency curve; and constructing a demodulation phase function based on the curve, performing generalized demodulation and narrow-band filtering on an original signal, extracting a pure harmonic component, and finally reconstructing a final rotating speed curve of a corresponding shaft system through instantaneous phase differential. According to the method, high-precision and anti-interference decoupling and estimation of the rotating speed of each shafting under a strong interference background are realized.
Owner:NORTHWESTERN POLYTECHNICAL UNIV

Circumferential liquid film surface wave observation device and method based on miniature high-speed camera

The invention discloses a circumferential liquid film surface wave observation device and method based on a miniature high-speed camera. The circumferential liquid film surface wave observation device comprises a centrifugal nozzle, a laser, the high-speed miniature camera and a synchronizer, the centrifugal nozzle can spray a conical liquid film; the high-speed miniature camera is located at the central gas nucleus of the conical liquid film, and the optical axis coincides with the axis of the centrifugal nozzle; a narrow-band optical filter is arranged on the surface of an optical lens of the high-speed miniature camera; the laser can emit plane laser perpendicular to the axis of the centrifugal nozzle to the conical liquid film; wherein the wavelength of the planar laser is equal to the central wavelength of the narrow-band optical filter; and the synchronizer is respectively connected with the laser and the high-speed miniature camera. According to the method, a frozen instantaneous circumferential liquid film form without background interference can be obtained, a surface wave growth factor and a breaking critical criterion can be accurately quantified, and the development and evolution process of the circumferential surface wave of the liquid film is further obtained through high-speed shooting.
Owner:PLA PEOPLES LIBERATION ARMY OF CHINA STRATEGIC SUPPORT FORCE AEROSPACE ENG UNIV +1

Multi-modal endoscope image fusion analysis method

The invention discloses a multi-modal endoscope image fusion analysis method, and relates to the technical field of medical image navigation, and the method comprises the steps: collecting an original white light image and an original narrow-band image, carrying out the preprocessing, and collecting real-time pose parameters; extracting blood vessel texture features in the preprocessed original white light image and the original narrow-band image, generating a binary semantic mask, calculating a spatial transformation matrix according to the binary semantic mask, and generating preliminary visual deformation field data; and calculating microscopic deformation field data according to a pre-stored biomechanical characteristic database, the preliminary visual deformation field data and the real-time pose parameters, carrying out reverse calculation to obtain physical deformation compensation field data, and carrying out spatial superposition operation on the physical deformation compensation field data and the preliminary visual deformation field data to obtain comprehensive compensation deformation field data. According to the method, real-time quantitative evaluation and abnormal early warning of the reliability of the fusion result are realized through multi-modal fusion quality early warning judgment, and the clinical decision credibility and the operation safety are enhanced.
Owner:EAST CHINA DIGITAL MEDICAL ENG RES INST +1

Narrowband-broadband intelligent switching method of radar

The invention discloses a narrowband-broadband intelligent switching method of a radar, and belongs to the field of radar signal processing. Single radar wide-narrow band function integration is achieved through resource multiplexing, self-adaptive triggering and dynamic parameter configuration, detection tracking in a default narrow band mode is achieved, switching is triggered based on manual instructions and double thresholds, hardware such as a common antenna and a T / R assembly is reconstructed through time division multiplexing and software parameters, the signal synchronization time is shortened, and the target tracking response delay time is shortened; double-radar collaborative design is not needed, and the design workload is reduced. According to the invention, double radars are combined into a single radar, the hardware cost is greatly reduced, and the method is suitable for unmanned aerial vehicle-mounted, vehicle-mounted and other space-limited scenes and military reconnaissance, civil security and protection and other tasks.
Owner:JIANGSU NORTH ELECTRONIC CO LTD

Polarization selectivity all-dielectric high-saturation structural color metasurface with maintainable color center

The invention provides a polarization selectivity all-dielectric high-saturation structural color metasurface with a maintainable color center. The metasurface sequentially comprises a SiO2 semi-ellipsoid layer, a GaN elliptic cylinder array and a PDMS flexible substrate from top to bottom, wherein the SiO2 semi-ellipsoid layer and the GaN elliptic cylinder array form a periodically arranged double-layer all-dielectric nanostructure unit. Under the condition of x polarization incidence, the structure generates a narrow-band high-reflection structural color in a visible light wave band, the full width at half maximum of a main reflection peak is about 9 nm, the peak reflectivity can reach 99.8% or above, and the reflectivity of a secondary reflection peak on the short wave side is lower than 0.01; and under the y polarization incidence condition orthogonal to the light source, the reflectivity near the corresponding wavelength is lower than 2%, and the light source shows remarkable polarization selectivity. The inventor further finds that when the equivalent radius change of the nano unit causes the reduction of the reflection efficiency, the reflectivity of the main peak can be recovered by adjusting the long-short axis ratio of the GaN elliptic cylinder and the SiO2 semi-ellipsoid, and the central wavelength of the main formant is basically kept unchanged, so that the brightness adjustment is realized on the premise that the color center is basically constant. The structure is suitable for flexible or wearable optical devices, polarization-related structural color display and other applications.
Owner:GUILIN UNIV OF ELECTRONIC TECH

Red light and infrared light-emitting compounds based on boron-nitrogen fused ring and application of red light and infrared light-emitting compounds

The invention provides a red light and infrared light-emitting compound based on a boron-nitrogen fused ring and application thereof. The invention provides a boron-nitrogen polycyclic aromatic hydrocarbon material of a fused naphthalene ring, and a specific strong electron withdrawing group is introduced to a boron atom para-position. Compared with a compound disclosed in the prior art, the compound provided by the invention introduces a strong electron withdrawing group to a boron atom para-position of boron-nitrogen polycyclic aromatic hydrocarbon of a fused naphthalene ring, so that the emission spectrum of the material can be subjected to significant red shift (red shift from a yellow light band to a red light band and even an infrared band), and red light and even infrared light emission with high luminous efficiency and a narrow band can be realized. An electroluminescent device prepared from the compound provided by the invention shows relatively high luminescent color purity and relatively excellent luminous efficiency, and can meet the requirements of current enterprise production on high-performance luminescent materials.
Owner:THE FIRST AFFILIATED HOSPITAL OF XIAMEN UNIV +1

Lightning multi-frequency signal data fusion positioning method

The invention relates to the technical field of atmospheric science detection, in particular to a lightning radiation source positioning method based on multi-station synchronous observation. Comprising the following steps: synchronously acquiring lightning broadband electromagnetic signals by multiple stations and performing time-frequency analysis; by calculating indexes such as cross-station coherence and interference level, high-quality frequency points are intelligently screened out to suppress noise and interference; reconstructing a narrow-band signal for each high-quality frequency point and performing high-precision time difference (TDOA) estimation by adopting an improved generalized cross-correlation method; and carrying out weighted fusion on TDOA measurement values of a plurality of high-quality frequency points, carrying out optimization solution by adopting a Grid Search algorithm, and finally obtaining a three-dimensional coordinate of lightning. Through intelligent screening of high-quality frequency points, accurate time difference estimation, optimization of a positioning algorithm, multi-band information fusion and intelligent processing, the defects that a traditional single-band positioning method is prone to interference and limited in precision are effectively overcome, the lightning positioning precision, the anti-interference capability and the reliability are remarkably improved, and the method is suitable for popularization and application. And the lightning positioning requirements in various environments are met.
Owner:INST OF ATMOSPHERIC PHYSICS CHINESE ACADEMY SCI