123results about How to "Reduce background noise" patented technology

The invention relates to the technical field of image processing, and discloses a scoliosis angle intelligent measurement method and system based on spine CT three-dimensional reconstruction. The method comprises the following steps: carrying out adaptive threshold segmentation and gray optimization processing on a spine CT sequence image to obtain a standardized preprocessed image, and carrying out adaptive bone tissue region identification and boundary enhancement processing to obtain spine skeleton segmentation data; performing three-dimensional grid construction and curved surface smoothing processing on the spine skeleton segmentation data to obtain spine three-dimensional model data; carrying out centrum gap identification and key point positioning processing on the spine three-dimensional model data to obtain a centrum feature data set, and carrying out spine midline curve construction and end centrum marking processing to obtain Cobb angle data; and performing three-dimensional space reconstruction and multi-plane projection processing on the Cobb angle data to obtain a measurement result report. According to the method and the device, full-automatic processing from acquisition of the CT image to generation of the final measurement result report is realized on the premise of ensuring the measurement accuracy.

The invention discloses a reservoir bank slope crack identification method based on unmanned aerial vehicle inspection and digital images, and relates to the technical field of reservoir bank slope inspection. 2, image preprocessing: preprocessing the data by adopting processing methods of graying, gray enhancement and bilateral filtering; 3, crack identification: identifying reservoir bank slope cracks in the image by adopting methods of threshold segmentation, edge detection and supervised classification; 4, crack pixel filtering: performing filtering processing on the extracted crack image by adopting morphological closed operation, length filtering and direction filtering; and 5, model fusion: fusing the threshold segmentation model, the edge detection model and the supervised classification model together by adopting a minimum-risk Bayesian probability method. The method shows remarkable applicability and effect in large-range and multi-form crack identification and investigation, and shows high robustness when processing crack images with different scales, shapes and backgrounds, and the accuracy of the method can stably reach more than 90%.

The invention discloses a self-adaptive calibration method and device for coal quality detection environmental influence correction, and belongs to the technical field of coal quality detection.The self-adaptive calibration method comprises the steps of (1) spectrum pretreatment and (2) LIBS spectrum characteristic peak intensity correction. The device comprises a control host, a spectrograph, a laser generator and a rotating disc type sample table. According to the invention, the problems of laser energy fluctuation, unstable spectral data quality and easy interference of environmental factors on the signal intensity of the characteristic peak in the use process of LIBS detection equipment are solved.

The invention relates to a three-dimensional aquatic vegetation canopy reflection characteristic modeling method based on a real scene. The method comprises the following steps that leaf reflection and transmission spectrums are obtained through calculation of a plant leaf radiation transmission model; in combination with an actual aquatic vegetation scene, vegetation canopy reflection characteristics are described through canopy structure parameters and leaf BRDF; calibrating model parameters by adopting four-flow approximation and linear approximation, and applying the model parameters to approximate solution of vegetation canopy reflectivity; finally, a LuxCoreRender physical rendering engine is used for coupling input parameters such as incident radiation, vegetation canopy reflection factors, water optical attribute parameters and observation geometry, and the vegetation canopy reflectivity is calculated in combination with an aquatic vegetation scene. According to the method, a high-precision three-dimensional aquatic vegetation canopy reflection model is established, remote sensing radiation modeling precision and application value can be improved, an important tool platform is provided for wetland remote sensing monitoring and ecological protection and coastal wetland blue carbon sink function evaluation, and the method has popularization and application prospects.

The invention relates to the technical field of dormitory access control, in particular to a voice recognition method and system for dormitory access control, and the method comprises the following steps: S1, voice data collection: collecting a voice signal of a user through a voice collection device arranged at a dormitory doorway; s2, signal preprocessing: preprocessing the collected voice signals; s3, transient noise detection and processing: identifying and processing transient noise; s4, feature extraction: performing feature extraction on the voice signal after transient noise processing; s5, voice recognition model training: generating a voice feature library; s6, voice matching: judging whether the user is a legal user; and S7, verification and feedback: after matching succeeds, sending a verification pass signal, opening a dormitory access control, and if matching fails, sending a verification failure signal, and prompting to re-input the voice signal. According to the invention, high-efficiency speech recognition performance can be maintained in a changeable and complex environment.

The invention provides an image classification method based on noise suppression and multi-scale feature fusion, and the method comprises the steps: building a data set, building a fine-grained image classification model, building a loss function, and classifying images. And respectively training, verifying and testing the fine-grained image classification model by using the training set, the verification set and the test set to obtain a trained fine-grained image classification model, and carrying out image classification to obtain a classification result. According to the invention, the noise suppression module and the multi-scale feature fusion module are introduced to reduce background noise and obtain the possibility of fine-grained category discrimination feature representation in foreground regions of different scales, so that the fine-grained feature representation gathers shallow features and deep features, and the accuracy of the fine-grained category discrimination feature representation is improved. And the performance of the model for a fine-grained classification task is improved.

The invention relates to a water quality detection method for detecting heavy metal elements in water, which comprises the following steps: S1, pretreating a water sample, and filtering to remove suspended particles and impurities; s2, acid digestion of the sample: digesting the sample by using a mixed solution of nitric acid and hydrochloric acid to release heavy metal elements; s3, electrochemical sensor detection: anodic stripping voltammetry (ASV) or differential pulse voltammetry (DPV) is adopted for detection, and the sensor uses a gold-plated electrode or a glassy carbon electrode modified with carbon nanotubes and graphene; s4, concentration calculation: calculating the heavy metal concentration according to a current peak value and a volume correction formula; and S5, verifying a result, and rechecking a detection result by adopting an ICP-MS or AAS method. The method is high in sensitivity, can accurately detect trace heavy metals in drinking water, industrial wastewater, surface water and underground water, is suitable for simultaneous detection of multiple elements, has the advantages of simplicity and convenience in operation, portability of equipment, high detection speed and the like, and is particularly suitable for on-site water quality monitoring.

The invention discloses a high-noise-immunity ranging imaging method and system based on quantum correlation measurement, belongs to the technical field of quantum radar and single photon detection, and particularly relates to a high-noise-immunity ranging imaging system and method based on quantum correlation measurement. Comprising a narrowband energy-time entangled two-photon source, a free space optical transceiving unit and a physical information acquisition unit, two photons with entanglement characteristics output by the narrowband energy-time entanglement two-photon source are respectively input into the free space optical transceiver unit and the physical information acquisition unit. The physical information acquisition unit jointly receives the photons directly output by the narrowband energy-time entanglement two-photon source and the photons output by the free space optical transceiving unit, so that the physical information of the measured object is obtained; according to the invention, the problems of small signal-to-background ratio and input saturation of the single-photon detector in the quantum correlation measurement field are solved, so that the system can carry out clear imaging under the condition of larger background noise.

The invention relates to a digital PCR liquid drop identification method and system based on an artificial intelligence algorithm, and the method comprises the steps: generating liquid drops through a micro-fluidic chip, and placing the micro-fluidic chip in PCR equipment for PCR reaction circulation; after the PCR reaction circulation is finished, placing the micro-fluidic chip under a microscope for observation so as to capture a PCR liquid drop image; and preprocessing the PCR liquid drop image, inputting the preprocessed PCR liquid drop image into a pre-constructed liquid drop identification model, and outputting to obtain a PCR liquid drop detection result. Compared with the prior art, on one hand, the micro-fluidic chip is designed, liquid drops with stable structures and consistent sizes can be generated, on the other hand, by introducing the pre-trained artificial intelligence model, efficient identification of the number of the liquid drops and intelligent judgment of a threshold value are achieved, background noise can be effectively reduced, and meanwhile the detection accuracy is improved. And the accuracy of liquid drop identification is obviously improved.

The invention discloses a satellite video moving target detection method based on intrinsic decomposition, relates to the satellite video moving target detection method based on intrinsic decomposition, and belongs to the field of remote sensing image processing. The invention aims to solve the problems that an existing satellite video moving target detection method based on deep learning seriously depends on a large-scale accurately-labeled data set and needs a long training process; and a traditional image processing technology may not fully suppress background noise in a complex scene. The method comprises the following steps: obtaining an optimization problem based on a time-space consistency constraint of a reflectivity component, a local space consistency constraint of a light and shade component and a signal decomposition constraint; solving the optimization problem to obtain a reflectivity component and a light and shade component; tensor robust principal component analysis is carried out on the reflectivity component, and a moving target is extracted; and processing the extracted moving target by using a noise filter, and outputting a final detection result.

The invention provides a static water low-noise hydrodynamic noise rotation test device which comprises a stepping motor and a speed reducer located below the stepping motor, a rotating shaft of a rotating arm is connected with the speed reducer through a damping device, and a sectional type variable-length suspender is used for connecting a test model and the rotating arm. The stepping motor and the speed reducer are installed on the supporting frame through the double-layer vibration isolation device, and the stepping motor and the speed reducer can push the rotating arm to rotate so as to drive the test model to do large-diameter rotary motion. The test device disclosed by the invention can be used for carrying out a rotation test in a relatively large water pool or a lake or on the sea, and controlling sound radiation of mechanical vibration noise to underwater at the same time, so that background noise is effectively reduced, and measurement of flow-induced vibration noise of a large-scale model is realized.

The invention belongs to an electrochemiluminescence aptamer sensor, and relates to a resonance energy transfer electrochemiluminescence aptamer sensor based on Ag < + > (at) Eu MOF / HOF and application thereof in acetamiprid detection. A rod-like hydrogen bond organic framework is used as a precursor, and lanthanide Eu < 3 + > is doped. The electrochemical luminescence aptamer sensor for resonance energy transfer is prepared by taking Ag < + > as a co-reactant accelerant, synthesizing Ag < + > (at) Eu MOF / HOF as an energy donor of a resonance energy transfer system and taking leaf-shaped CdS (at) Au-cDNA as an energy receptor. The sensor is used for ACE detection, and has a wide linear range and a low detection limit. The prepared novel Ag < + >-coated Eu MOF / HOF electrochemical luminescence material is applied to electrochemical luminescence detection for the first time and used for detecting acetamiprid residues in water, and an effective and convenient strategy is developed for analysis and detection of pollutants in a water environment.

The invention belongs to the technical field of electric vehicle speed reducers, and relates to a PSO-MCKD-based gear early fault diagnosis method, which comprises the following steps: firstly, adaptively optimizing parameters L and T in an MCKD algorithm by applying PSO for an acquired gear early fault signal containing a relatively weak gear early fault signal; based on the MCKD algorithm after parameter optimization, impact component enhancement is carried out on the early fault signal; thirdly, analyzing the enhanced signal by using an envelope spectrum analysis method, and comparing the enhanced signal with a theoretical fault feature; and finally, outputting a diagnosis result. According to the method, the problem that the parameters L and T of the MCKD cannot be optimal at the same time is solved, adaptive optimization is carried out on the parameters of the MCKD by adopting PSO, the problem that early fault features of the gear cannot be accurately extracted is solved, noise reduction is carried out on an original signal by using the optimized MCKD, and envelope spectrum demodulation is carried out to extract the fault features, so that the accuracy of the fault feature extraction is improved. And the efficiency and accuracy of early weak fault feature diagnosis of the gear are improved.

The invention discloses application of a prognostic marker H4K5la in prognostic evaluation of neuroblastoma, and relates to the technical field of biology. The invention provides application of the H4K5la detection reagent in preparation of products for judging prognosis of neuroblastoma, prognosis evaluation accuracy is improved by detecting the expression level of H4K5la, the detection cost is reduced by the detection method, detection sensitivity and specificity are enhanced, a theoretical basis is provided for a treatment intervention strategy of targeted H4K5la, and the application of the H4K5la detection reagent in preparation of products for judging prognosis of neuroblastoma is provided. Important reference can be provided for further treatment development.

The invention provides a sound event classification method for reducing reverberation based on frequency band division, which can effectively reduce the influence of background noise such as reverberation and improve the accuracy of sound classification and recognition. A to-be-processed audio signal is converted from a time domain to a frequency domain to obtain a to-be-processed spectrum signal, the to-be-processed spectrum signal is subjected to frequency division ratio control of frequency band bandwidth and reverberation reduction of a selected frequency band to obtain a reverberation-reduced spectrum signal, and the reverberation-reduced spectrum signal is combined with other signals to obtain a finally-output spectrum signal after reverberation reduction. Converting the frequency spectrum signal into a time domain signal and outputting the time domain signal; a training set after data enhancement is formed based on a final output time domain signal, and a sound event classification model is trained, so that the characterization capability of the sound event classification model to features is indirectly enhanced.

The present invention discloses a method for evaluating bacterial activity based on GelRed dye, wherein metal ions are first mixed with bacterial samples, and then allowed to stand for a certain period of time to obtain a mixed bacterial solution, and then GelRed dye is added to the mixed bacterial solution to mix evenly and then allowed to stand for a certain period of time; ultrapure water is added for centrifugation, the supernatant is discarded, and then Syto9 solution is added for mixing; finally, a fluorescence photometer is used for detection. The evaluation method of the present invention has the characteristics of high sensitivity, rapidity and low toxicity.

The invention discloses a kit for rapidly detecting group B streptococcus by combining rapid enrichment with a visual up-conversion technology and a detection method thereof, and belongs to the technical field of microorganisms. The kit comprises a shell, a disposable sterile plastic tube, a group B streptococcus detection card and an enrichment culture bottle, the method comprises the steps of enrichment of clinical samples and detection of group B streptococcus. The enrichment mode is that a liquid enrichment culture medium is oscillated for 4 hours to finish enrichment; according to the group B streptococcus detection card, the bimodal nano-probe labeled GBS monoclonal antibody and rabbit IgG antibody, the nano-probe fluorescence intensity is remarkably enhanced through the plasma enhancement effect of silver, and the group B streptococcus detection card has the advantages of high absorbance visual colorimetric effect of nano-silver and low background noise and high sensitivity of up-conversion luminescence. Compared with a traditional detection method, the method has the advantages that the detection time is greatly shortened, the operation is simple, expensive instruments and professional operation are not needed, clinicians can be timely guided to carry out antibiotic preventive medication for acute puerperae, and the infection probability of newborns is reduced.

The application discloses a sound-absorbing and sound-insulating material and relates to the technical field of sound-absorbing and sound-insulating materials. The sound-absorbing and sound-insulating material is characterized in that PET hollow fibers are used as a framework, PP melt-blown fibers are used as filling materials to form a high-frequency sound-absorbing layer, the PET hollow fibers are used as a framework structure to ensure that the sound-absorbing and sound-insulating material has sufficient strength and stability, and melt-blown cloth fluff is added to the high-frequency sound-absorbing layer to prepare a low-frequency sound-absorbing layer. The PP melt-blown fibers are directly deposited and embedded into the PET fiber framework to form a material with small pores but many pores. The high-frequency sound-absorbing layer and the low-frequency sound-absorbing layer are layered and stacked, and non-woven fabric is arranged on the outer surface to form a novel sound-absorbing and sound-insulating material. The sound-absorbing and sound-insulating material not only has better sound-absorbing performance, but also has improved low-frequency sound-absorbing performance.

The invention relates to the technical field of biology, in particular to a single-molecule immunodetection method based on enzymatic reaction. In the aspect of dispersing the magnetic particle carrier, the problem that the loading efficiency is unstable due to the fact that the magnetic particle carrier falls into holes in a microwell plate is solved, meanwhile, background noise and signal scattering can be reduced, the detection sensitivity can be improved, and very low-concentration protein can be detected; meanwhile, all the liquid drops can be counted at the same time by adopting optical imaging equipment, so that the accuracy is improved, and the CV value is reduced.

The application belongs to the technical field of food safety detection, and particularly relates to a photoelectrochemical aptamer sensor based on a CdS / AuNPs / SnS2 heterojunction and application thereof in detection of zearalenone. The photoelectrochemical aptamer sensor comprises a sensing working electrode and a signal control agent. The sensing working electrode is formed by modifying a CdS / AuNPs / SnS2 heterojunction as a photoactive material on the surface of a conductive glass substrate, and then modifying a capture probe and a signal probe compound in sequence. The signal probe compound is composed of graphene oxide, horseradish peroxidase, gold nanoparticles and a zearalenone aptamer. The signal control agent is a mixed solution of 4-chloro-1-naphthol and hydrogen peroxide. The photoelectrochemical aptamer sensor based on the CdS / AuNPs / SnS2 heterojunction can realize high-sensitivity detection of zearalenone, and has the advantages of stable photocurrent response, high sensitivity, low background signal and strong anti-interference ability.

The invention discloses an ultrafast space-time light field measurement system and method, and the method comprises the steps: carrying out the dispersion separation of an interference light field generated after the superposition of a to-be-measured laser pulse and a reference pulse, and carrying out the wavelength screening of the interference light field after the dispersion separation through a wavelength screening element, and obtaining a laser light field with a target wavelength, acquiring light field complex amplitude information corresponding to the laser light field of the target wavelength; and reconstructing according to the light field complex amplitude information to obtain a light field corresponding to the laser pulse to be measured. According to the system and the method disclosed by the invention, the delay between the signal light and the reference light in the measured laser pulse does not need to be regulated and controlled, and the ultrafast space-time light field can be reconstructed only by enabling the same-frequency components to interfere in the same spatial position to obtain the interference pattern of each frequency. The method provided by the invention has the characteristics of convenience in implementation, interference resistance, low background noise, low data volume, high measurement efficiency and high measurement result accuracy.

The invention discloses a near-infrared iron ion fluorescent probe as well as preparation and application thereof, and belongs to the technical field of analytical chemistry and biology. The excitation wavelength and the emission wavelength of the fluorescent probe disclosed by the invention are both located in a near-infrared region, the fluorescent probe has excellent selection performance on ferrous ions, can realize rapid detection on endogenous and exogenous ferrous ions of cells, can effectively avoid interference of autofluorescence of a sample, and improves the signal-to-noise ratio; the probe can be positioned in mitochondria, is crucial to research on the dynamic state and function of ferrous ions in the mitochondria, can rapidly image endogenous and exogenous ferrous ions in tumor cells in real time, shows a good biological fluorescence imaging application prospect, provides a powerful tool for tumor research, is beneficial to revealing the effect of the ferrous ions in tumors, and has a wide application prospect. The targeted treatment effect is evaluated, and the treatment scheme is optimized. The kit has potential clinical value in the aspects of tumor diagnosis, treatment monitoring, prognosis evaluation and the like, and has important technical effects and wide application prospects in biomedical research and clinical diagnosis.

A sample collection system includes a housing including an air inlet configured to receive an exhaled airflow; a porous sample collection medium disposed within the housing, the porous sample collection medium comprising a sample receiving region; an airflow passage extending from the air inlet through the sample receiving region of the porous sample collection medium; an assay device configured to receive the eluted sample from the porous sample collection medium; and a liquid flow passage extending from the sample receiving region of the porous sample collection medium to the assay device. The porous sample collection medium includes one or more reagents disposed on the porous sample collection medium along a liquid flow path.

The invention discloses a solar-blind ultraviolet photoelectric artificial visual synaptic device based on an aluminum-yttrium-nitrogen thin film and a preparation method of the solar-blind ultraviolet photoelectric artificial visual synaptic device, and relates to the field of novel micro-nano electronic materials and functional devices. The synaptic device comprises a substrate, a bottom electrode, a solar blind ultraviolet light response resistive layer and a top electrode, the bottom electrode is arranged on the substrate and is used for introducing a solar blind ultraviolet light signal; the solar blind ultraviolet light response resistive layer is arranged between the bottom electrode and the top electrode and used for simulating synaptic plasticity. Wherein the solar-blind ultraviolet light response resistance change layer is made of an aluminum-yttrium-nitrogen film with a photoconductive effect, and has photoresponse to solar-blind ultraviolet light with the wavelength of 200-280nm; the bottom electrode is a transparent conductive electrode; an electric signal is input through the top electrode and the bottom electrode, and a solar blind ultraviolet light signal is input through the transparent conductive bottom electrode; the synaptic device provided by the invention can realize various photoelectric synaptic plasticity under the excitation of an electric signal and a solar-blind ultraviolet light signal, so that the simulation of an artificial visual function is realized on the basis of the synaptic device.

This invention discloses a multi-target combined detection kit for detecting vitiligo-related factors and its preparation method. The kit includes multiple detection reagents, each comprising a solid-phase capture carrier, a labeled antibody solution, and an antibody gradient concentration calibrator. The antibodies in the labeled antibody solution and the antibody gradient concentration calibrator are CXCL9, CXCL10, CCL20, and HMGB1. This kit enables the simultaneous determination of the levels of CXCL9, CXCL10, CCL20, and HMGB1 in a sample using a unified detection platform and in a single detection experiment. The kit offers advantages such as high sensitivity, a wide linear range, and fast detection speed, accurately detecting target molecules at low levels in samples and meeting clinical requirements for detection accuracy and efficiency.

This invention provides a split-type cold screen for an infrared detector and its assembly method. The split-type cold screen for the infrared detector includes a cold screen body and matte fins. The assembly method includes: applying a black coating to both the cold screen body and the matte fins, pre-baking them, then initially assembling the pre-baked cold screen body and the matte fins, and finally baking the pre-assembled cold screen to complete the assembly. This invention places the cold screen assembly step after pre-baking and before baking, using the bonding force of the black coating to connect the cold screen body and the matte fins. This eliminates the adhesive bonding step in the split-type cold screen assembly process, solving the problem of using adhesives to bond the cold screen body and matte fins in the split-type cold screen assembly process. This ensures good mechanical reliability of the cold screen assembly in low-temperature vibration environments and also improves the performance of the detector components and the efficiency of the cold screen assembly process.

The invention provides an in-situ imaging method capable of realizing specific modification visualization of target nucleic acid in cells. According to the method, only three single-stranded nucleic acids with different functions, namely a single-stranded nucleic acid bracket assembled with a specific modification component for identifying nucleic acid, a single-stranded nucleic acid primer 1 and a single-stranded nucleic acid primer 2 capable of specifically targeting a target nucleic acid sequence, are needed, so that targeting of specific modification and a specific nucleic acid sequence can be completed, and a signal amplification system for rolling circle amplification is formed; the method has the characteristics of simplicity, convenience and economy, and has extremely high commercial potential. A long single-stranded nucleic acid with a repeated sequence is formed after in-situ rolling circle amplification, a specific fluorescent probe can be enriched for imaging, and an imaging signal point at the position is the spatial position of a specific modification site of the target nucleic acid. The method can be shared with protein immunofluorescence, simultaneous imaging of multiple nucleic acids can be achieved, nucleic acid imaging of different subspace localization can be achieved, and the method becomes a multifunctional solution capable of being applied to multiple scenes.

The invention provides a pumping detection TAP instrument, and relates to the field of transient dynamics and catalytic surface and interface research. The pumping detection TAP instrument provided by the invention comprises a sample injection pulse system, a micro reactor, a liquid nitrogen cooling system, a mass spectrum system and a vacuum system. Through the arrangement, the experiment of continuous pulse or intermittent pulse or pump-probe pulse of one or two gas molecules can be realized, so that surface chemistry and microdynamics information related to element steps can be obtained.

The invention provides a coronary artery image segmentation method based on improved nnUnet, and relates to the field of medical image segmentation. The method comprises the following steps: acquiring a training data set containing a CTA image of a normal coronary artery blood vessel and a CTA image of a lesion coronary artery blood vessel; adjusting the window width and the window level of the image; re-sampling the interlayer spacing of all the images in the training data set; a preprocessing module is constructed, the preprocessing module comprises an equalization sub-module and a filtering sub-module, and each layer of two-dimensional image of all CTA images in the training data set is preprocessed through the preprocessing module; constructing a segmentation model, and training the segmentation model by using the preprocessed image; and after a to-be-processed CTA image passes through the preprocessing module and the trained segmentation model, a segmentation result image is obtained. According to the method, the accuracy and continuity of coronary artery segmentation are improved, and the requirement of three-dimensional reconstruction of the coronary artery CTA image can be widely met.

The present invention provides an electrically driven quantum dot single photon source and a preparation method thereof, wherein the electrically driven quantum dot single photon source comprises a substrate, a positive electrode, a hole injection layer, a quantum dot light-emitting layer, an electron injection layer, and a negative electrode which are arranged in sequence; wherein the quantum dot light-emitting layer comprises an insulating film and quantum dots located in the insulating film and in contact with the hole injection layer, and the material of the quantum dots is silver sulfide. By improving the particle size and distribution design of quantum dots, the selection of materials, the device structure, and other aspects, an electrically driven single photon source which works at a communication wavelength, has high efficiency, has almost no multi-photon emission, has low background noise, and is environmentally friendly is obtained.