705 results about "Wave crest" patented technology

The invention relates to the technical field of disaster monitoring, in particular to a mine inrush water image processing system based on AI recognition, which comprises a fissure water flow tracking module, a voiceprint disturbance extraction module, an acceleration mapping module, a form analysis module and a risk output module. According to the method, a fine voiceprint perturbation sequence is formed by extracting crack water flow boundary pixel coordinates from continuous frame images, accurately capturing water flow micro-displacement and generating a deviation track in combination with an inter-frame difference between a gray gradient amplitude and a direction angle, and synchronously extracting a liquid level perturbation wave crest position and a voiceprint primary and secondary frequency amplitude difference; the acceleration is calculated according to the pixel displacement speed and mapped to a time axis, so that the boundary movement trend and morphological change are synchronously analyzed in the time dimension, risk frame locking is completed by multi-source signals in the same time period under double-threshold judgment, and three-dimensional presentation of the water flow dynamic state is achieved. The accuracy and reliability of sudden water gushing risk judgment in a complex mine environment are remarkably improved, and the probability of missing detection and misjudgment is reduced.

The invention discloses a large-section long-footage mechanical blasting mixed excavation method suitable for a subway station, and relates to the technical field of underground rail transit engineering, and the method comprises the following steps: obtaining a tunnel section contour, a geologic structure and blasting parameters, building a three-dimensional blasting wave propagation inversion model, and combining geology and material heterogeneity to obtain a three-dimensional blasting wave propagation inversion model; and identifying a closed space region forming reflection interference, and predicting a space point location where blasting wave energy is abnormally accumulated. Based on the three-dimensional blasting wave propagation inversion model, the abnormal wave energy accumulation area is predicted in combination with geological heterogeneity, the high-risk blasting section is recognized, parameters are reconstructed, vibration real-time monitoring and model feedback correction are assisted, a closed-loop control system is constructed, local wave crest abnormity is effectively restrained, and the safety and controllability of large-section tunnel blasting construction are improved.

The invention relates to the technical field of vibration monitoring, in particular to a self-powered transmission line fitting aeolian vibration damage diagnosis system and method, and the system comprises a sensing collection module, a signal decoupling module, a damage identification module, a damage association module and a risk assessment module. According to the method, stress wave velocity and acceleration data are synchronously collected, time alignment is implemented, feature coupling precision is enhanced, wave crest offset and energy density are respectively extracted by using moving average filtering and wavelet transform, effective data segments are dynamically screened, and environmental noise interference is suppressed. A stress wave propagation change rate is quantified based on a path attenuation model, a continuous energy abnormal node is matched to realize damage positioning, a breeze response abnormal region is identified by combining vibration direction change and a signal envelope offset degree, multi-dimensional features are coded and subjected to risk judgment through a neural network, a damage positioning and risk assessment closed-loop framework is formed, and the risk assessment accuracy is improved. And the spatial resolution and evaluation precision of aeolian vibration damage identification under complex working conditions are significantly improved.

The invention discloses a signal detrending method based on sliding window statistics and dynamic wave crest correction. The method comprises the step of realizing accurate extraction of signal trend and fluctuation characteristics through a double-window dynamic adjustment mechanism of a mean value window and a standard deviation window. A detection threshold value is dynamically adjusted by analyzing the change trend of the historical wave crest amplitude, and the real-time tracking capability of signal fluctuation is ensured; meanwhile, different parameter configurations are preset for different application scenes, the problem of missing detection or misjudgment generated when the amplitude of a fixed threshold algorithm changes suddenly is solved, and the wave crest recognition accuracy is improved. Based on a dynamic threshold algorithm, wave peak start and end points are automatically identified, a linear interpolation technology is adopted to calculate slope of each interval, fitting parameters are dynamically adjusted through residual analysis, and finally low-frequency trend terms and high-frequency characteristic components are effectively separated through difference operation of original signals and fitting signals. The problem of fitting deviation caused by non-uniform sampling can be effectively solved.

The invention provides a three-dimensional skin waviness fitting analysis method. The method comprises the following steps: performing boundary analysis on skin point cloud data obtained by laser measurement, performing interpolation sampling from the point cloud data according to a specified area and resolution to obtain point cloud coordinates which can reflect the real condition of the skin and are regularly arranged, performing bicubic spline surface least square approximation based on a sampling point set, and calculating the skin point cloud data according to the bicubic spline surface least square approximation. The method comprises the following steps: acquiring a reference curved surface reflecting the overall distribution trend of an analysis area, calculating distance deviation from a sampling point to the reference curved surface, carrying out filtering smoothing processing, forming a smooth deviation curved surface capable of reflecting the deviation condition of a measurement curved surface, extracting information such as wave crest and wave trough positions, wave amplitude, wavelength and slope in the deviation curved surface, and carrying out skin waviness characteristic analysis. According to the method, the tiny waviness characteristics of the irregular curvature surface of the aircraft can be extracted, the skin waviness distribution condition can be visually displayed, and the method has the advantages of being wide in applicability, small in error, high in reliability, low in time cost and the like.

The invention relates to the technical field of partial discharge detection, in particular to a partial discharge detection method and system for a high-low voltage switch cabinet, and the method comprises the steps: obtaining electromagnetic wave signals and power system voltage data of each sensor position in real time; acquiring a partial discharge period in each detection window according to the electromagnetic wave maximum value of all the sensors in each power frequency period in each detection window, the distance between the electromagnetic wave maximum value and the voltage wave crest and the voltage wave trough of the power system, and the electromagnetic wave signal difference between the sensors; and according to the dispersion degree of the electromagnetic wave maximum values of all the sensors under each partial discharge period in each detection window, the electromagnetic wave signal frequency domain energy of each partial discharge period and the proportion of the partial discharge period in each detection window, obtaining the existence confidence of each detection window, and judging whether partial discharge exists under the current detection window or not. According to the invention, by analyzing the distinguishing characteristics of the partial discharge and the electromagnetic interference in the electromagnetic wave signals at multiple positions, the detection precision of the partial discharge is improved.

The invention provides an aviation nacelle part waviness automatic detection and evaluation method, and belongs to the field of product production detection, and the method comprises the steps: carrying out the protocol scanning of part surface contour features, and obtaining the undistorted coordinate point discrete point cloud data of the actual surface contour; filtering the point cloud data; obtaining a piece of flattened deviation value discrete point cloud data; obtaining a flattened deviation value continuous curve by adopting a general standard curve reduction method; extracting waviness components, and obtaining a curve center line; obtaining a crest value and a trough value participating in calculation; and calculating the maximum wave amplitude, the waviness and the slope for evaluating the waviness by using the wave peak value and the wave trough value. According to the method, the relation between the minimum cut-off wavelength of the waviness and the sampling interval is stipulated, the undistorted reduction of the surface profile curve is ensured, the influence of non-waviness profile components in the digital evaluation of the waviness is eliminated through a combined calculation method, and the evaluation accuracy of the waviness of the aviation nacelle part is improved.

The invention discloses an ion chromatography wave crest boundary extraction method based on fitting residual and tangent judgment, and belongs to the technical field of ion chromatography analysis. Comprising the following steps: S1, reading an original waveform data sequence, and executing frequency reduction sampling according to a set step length; s2, calculating the slope of the data after underclocking sampling by using a difference method, and searching positive and negative slope sections by performing first-order derivation on the waveform after underclocking sampling; s3, noise interference is eliminated, slope areas are grouped, then a chromatographic peak detection limit value is set, and an effective peak left section and an effective peak right section are screened out; s4, combining the effective wave crest left side section and the effective wave crest right side section to obtain an effective wave crest and a preliminary left boundary point and a preliminary right boundary point of the effective wave crest; s5, fitting a straight line through the preliminary left boundary point and the preliminary right boundary point to position an error integral region; and S6, updating the optimal boundary point by traversing the evaluation indexes of all points in the error integral region. The boundary search range is more accurate, and the calculation efficiency is higher.

The invention provides an automatic digging method of an excavator based on image recognition, which is realized based on a material pool and the excavator, a laser radar and a binocular camera are arranged on the upper edge of the material pool, and the excavator comprises a digging arm, a double-bucket assembly and a control unit. The method comprises the following steps: determining a peak initial position by a laser radar material pile three-dimensional point cloud, and performing secondary calibration by a camera to obtain a peak final position and a slope angle; the control unit switches a first / second digging mode according to the distance between the wave crest and the excavator, the first mode controls the excavator bucket to conduct wall-attached digging and conduct bottoming detection through the pressure sensor, and the second mode adjusts the angle of the excavator bucket to conduct digging according to the slope angle; when no wave crest exists, a corresponding digging scheme exists, and the point cloud is updated after digging each time; the wave crest positioning precision and the environmental adaptability are improved, the digging efficiency is optimized, manual intervention is reduced, and the device is suitable for digging of materials such as cereals and gravels.

The invention discloses a corrugated steel web bridge deformation monitoring temperature lag compensation method and system, and the method comprises the steps: constructing time sequence data of a corrugated steel web, the time sequence data comprises a time sequence composed of a wave crest temperature, a wave trough temperature, a strain measurement value, a wind speed and solar radiation intensity in any fold period of the corrugated steel web at any moment; according to the time sequence data, calculating the temperature lag time of the temperature to the structure response by using a sliding cross correlation coefficient algorithm of the frequency domain energy weight; time sequence data are reconstructed according to the temperature lag time, and the reconstructed time sequence data are obtained to serve as state vectors of the corrugated steel web; the state vector of the corrugated steel web is input into the strategy network of reinforcement learning, an optimal action instruction of the next step is output and obtained, and the optimal action instruction comprises the step that a compensation signal is applied to time sequence data; according to the optimal action instruction, the predicted state vector of the corrugated steel web at the next moment is obtained; and obtaining a strain prediction value of the corrugated steel web according to the state vector of the corrugated steel web at the next moment. Dynamic and high-precision compensation of the corrugated web bridge temperature hysteresis effect is achieved for the first time.

The invention discloses a method for automatically calculating the waviness of an aircraft profile in an MATLAB environment, and the method comprises the steps: 1, obtaining the plane section point location data of the waviness of the aircraft profile based on the reverse point cloud data of the aircraft profile; and step 2, automatically calculating the airplane profile waviness in the MATLAB environment, including plane classification of point location data, three-dimensional coordinate system conversion, two-dimensional wave crest and wave trough point location calculation, wave crest and wave trough point coordinate system reverse conversion, waviness calculation and form report output on the point location data of the plane cross section obtained in the step 1 through a program in the MATLAB environment. Therefore, automatic calculation of the airplane appearance waviness is completed. According to the invention, the problem that the existing detection mode for the airplane profile corrugation is difficult to have convenient operability, detection precision and detection efficiency at the same time is solved.

The invention discloses a heart tension index dynamic calculation and risk assessment method based on HRV, and the method comprises the steps: carrying out the filtering and denoising of an electrocardiosignal through a Butterworth filter, and obtaining a filtered electrocardiosignal; calculating interval data of adjacent wave crests; processing the interval data according to fast Fourier transform to obtain frequency domain features, and combining the interval data to obtain time domain features; performing normalization processing on the time domain and frequency domain features based on a maximum and minimum normalization method; calculating a cardiac tension index according to the normalized features and a pre-trained multiple linear regression model; matching a pre-constructed reference database according to the individual age, gender and body mass index to obtain a reference cardiac tension index; calculating a cardiovascular risk score in combination with the normalized frequency domain features and a reference cardiac tension index; and repeating the above steps regularly, smoothing through a moving average method based on continuous multiple cardiovascular risk scores, and analyzing the trend to send out cardiovascular risk early warning information.

The invention relates to an automatic and semi-automatic electric arc technology, in particular to a hollow guide rail quick positioning and welding device and a positioning method.The hollow guide rail quick positioning and welding device comprises a base, a rolling conveying piece installed on the base and a hollow guide rail body arranged on the rolling conveying piece in a transmission mode; the positioning piece is arranged on the base and is used for lifting and positioning the welding seam of the hollow guide rail main body. Through the integral matching design, intermittent lifting action of the ejector rod can be realized, and when the ejector rod performs lifting motion, the positioning piece connected with the ejector rod performs lifting action synchronously, so that the welding seam of the hollow guide rail main body is accurately lifted and positioned, the wave fluctuation height difference caused by sinking is weakened, and the welding quality of the hollow guide rail main body is improved. The height difference between the wave crest and the wave trough which fluctuate is controlled within the range that a welding pool can melt along flow as much as possible, the lifting action of the ejector rod and the positioning piece is driven by the driving piece, the phenomenon can be effectively avoided, the flatness of a welding seam is ensured, and a good foundation is provided for welding operation.

The utility model belongs to the technical field of flexible structure design, and particularly relates to a perimeter-variable fuselage frame structure which comprises sliding groove sections, sliding key sections, corrugated beams, height-variable supporting columns and length-variable supporting rods. The corrugated beams are arranged on the outer sides of the sliding key sections and the sliding groove sections and are provided with wave crest and wave trough structures; the sliding key sections and the sliding groove sections are located on the inner sides of the corrugated beams, arranged at intervals and distributed in a staggered mode. The corrugated beams, the sliding key sections and the sliding groove sections are all of arc-shaped structures, and wave crests and wave troughs of the corrugated beams are arranged in the radial direction of the arc-shaped structures; the sliding key section and the sliding groove section are mutually nested to form an arc-shaped supporting sliding way, and the wave trough of the corrugated beam slides on the arc-shaped supporting sliding way; the height-variable supporting column and the length-variable supporting rod are hinged to the two ends of the sliding key section respectively. The shape of the fuselage can be greatly changed, the large-size fuselage can provide a large space to carry more fuel, and the small-size fuselage is beneficial for reducing flight resistance and improving the fuel utilization rate.

The invention relates to a light-weight network-based voltage wave crest and wave trough rapid identification method and system, and the method comprises the steps: constructing a multi-dimensional input vector through voltage and load current dual-channel synchronous collection and feature fusion; real-time reasoning is carried out on the voltage wave crest and wave trough probability based on a lightweight neural network, and a high-confidence-coefficient triggering mark signal is generated in combination with dynamic threshold value comparison; mapping the trigger mark into a multi-phase conduction time sequence deviation matrix by using an asymmetric phase deviation algorithm, and dynamically adjusting a phase difference parameter in combination with a load current; and through a complementary PWM control instruction group generation and closed-loop optimization mechanism, ripple cancellation of staggered conduction of the multi-phase switch tubes is realized. The method solves the problem of insufficient ripple suppression caused by high false triggering rate and rigid phase distribution in traditional fixed threshold detection, remarkably improves the voltage stability and dynamic response speed in a sudden change scene from light load to heavy load, and can be widely applied to high-precision power supply systems such as data centers and communication equipment.

The embodiment of the invention discloses a waviness determination method and device, electronic equipment and a storage medium, and the method comprises the steps: obtaining a target region of an aircraft and a three-dimensional point cloud model corresponding to the surface of the target region, and carrying out the sectioning processing of the three-dimensional point cloud model, and obtaining a sectioning spline curve of the three-dimensional point cloud model; determining coordinates of a target interpolation point according to the point cloud points on the sectioning spline curve, and generating an interpolation spline curve according to the coordinates of the target interpolation point; determining whether the interpolation spline curve is equivalent to the sectioning spline curve or not according to the curvature of the sectioning spline curve, the curvature of the interpolation spline curve and the distance between the sectioning spline curve and the interpolation spline curve; if yes, wave crest points and wave trough points of the interpolation spline curve are determined, the waviness of each corrugation on the surface of the target area is determined according to the wave crest points and the wave trough points of the interpolation spline curve, and the waviness of the surface of the aircraft can be accurately and efficiently determined.

The invention provides a composite bionic electric vehicle battery compartment with a lateral impact-resistant reinforcing structure, which is applied to the technical field of battery compartment design and comprises a bearing frame and a reinforcing flange, and the reinforcing flange comprises outer convex wave crest parts and inner concave wave trough parts which are sequentially and alternately arranged along the top outline of the bearing frame; the bearing frame comprises hollow bearing units, the bearing units are arranged in the main frame body and are sequentially and transversely arranged, and the adjacent units are connected through longitudinal reinforcing ribs; each bearing unit comprises a center part, inclined reinforcing ribs and transverse supporting ribs, the center part is of a regular hexagon structure formed by connecting six auxiliary reinforcing ribs, the upper auxiliary reinforcing rib and the lower auxiliary reinforcing rib are connected with the main frame body, the connecting ends of the left side and the right side are connected with the transverse supporting ribs respectively, and the inclined reinforcing ribs distributed in an array mode are arranged on the transverse supporting ribs; the inclined reinforcing ribs and the auxiliary reinforcing ribs at the corresponding positions are parallel and equal in length. According to the invention, the lateral impact resistance, bending resistance, torsion resistance and vibration reduction and energy absorption performance of the battery compartment are remarkably improved while the light weight is realized.

The application discloses a rotating mirror type binocular vision laser tracking light break recovery system and method. The system comprises a rotating mirror type laser tracker and a binocular vision module, two cameras in the binocular vision module are symmetrically installed on both sides of a laser beam, and camera visual axes and a laser optical axis are reflected to a working area through a rotating mirror of the tracker. The method comprises the following steps: a virtual imaging plane model in which the camera visual axes and the laser optical axis are coincident is constructed in advance; after the light break occurs, an infrared illumination light source of a vision system is modulated, frame difference images of modulation wave crests and troughs are acquired and processed, a current position of a target mirror and a predicted light break recovery rotation angle are obtained, and error compensation is performed on the current position and the predicted light break recovery rotation angle; and corresponding motors are driven to rotate according to the compensated light break recovery rotation angle, so that the laser beam is re-aligned to the target mirror. The application reduces the coaxial installation difficulty of a vision system of a rotating mirror type laser tracker, and improves the target mirror recognition rate and the light break recovery servo angle accuracy in a large range of complex environments.

The invention relates to the technical field of electrostatic dust collection and discloses an accurate frequency adjustment method for an intelligent frequency modulation high-voltage power supply of an electrostatic dust collector. The method comprises the steps of collecting voltage signals with frequency fluctuation in operation of a high-voltage power supply to form a voltage sequence; dividing period segments by using wave crest distribution in the voltage sequence, and clustering to obtain adjustment subsequences; obtaining a trend fluctuation index based on local signal change trend fluctuation and signal differences of the adjustment subsequences, and obtaining an amplitude drop difference and an amplitude interval difference according to an amplitude change trend difference and an amplitude bit sequence change trend difference; obtaining a period stability coefficient by combining the difference, the average condition of the trend fluctuation index and the average condition of the sub-sequence similarity; constructing a Hankel matrix and performing singular value decomposition, and obtaining a main component proportion and a difference index based on a singular value condition; and according to the Hankel matrix line data correlation, the period stability coefficient, the main component proportion and the difference index, obtaining a signal stability index, and according to the signal stability index, accurately adjusting the high-voltage power supply frequency.

The invention discloses a reinforced photoelectric composite cable of a coal mining machine, which belongs to the technical field of cables, and comprises a composite cable core structure, an armored protective layer and a sheath system, and the armored protective layer comprises a first steel belt, a second steel belt and a metal net braid layer, a third steel belt which is continuously bent to be of a wave structure is arranged in a cavity formed by the first steel belt and the second steel belt, the wave troughs of the third steel belt make contact with the inner wall of the first steel belt, and the wave crests of the third steel belt make contact with the inner wall of the second steel belt. The cable can be subjected to multi-dimensional mechanical property collaborative optimization under complex working conditions, the purpose of graded unloading is achieved through deformation of the steel plate, the situation that a traditional structure generally depends on rigid resistance of an armor layer is not needed, the flexibility is considered while the mechanical property is guaranteed, and the cable adapts to frequent bending scenes; and the long-term stable operation of the cable in a severe mine environment is further ensured.

The invention discloses an undisturbed sleep monitoring method and a related device, and the method comprises the steps: carrying out the feature extraction of a first piezoelectric signal, obtaining a body movement feature, and enabling the first piezoelectric signal to be obtained through the superposition of a plurality of preprocessed original piezoelectric signals; frequency domain analysis is carried out on the second piezoelectric signals, frequency components corresponding to wave crests are recognized in a sleep heart rate related frequency band, a frequency pair corresponding to each moment is extracted, a frequency set is obtained, the frequency pair comprises a plurality of preorder frequency components in the first frequency sequence and the frequency of each frequency component, and the frequency set is obtained; the first frequency sequence is obtained by arranging frequency components in a descending order according to amplitude intensity; determining heart rate characteristics at each moment according to the frequency set; performing feature extraction on the acquired piezoresistive signals to obtain piezoresistive features; and determining the sleep state according to the body movement characteristics, the heart rate characteristics at each moment and the piezoresistance characteristics. The reliability and accuracy of sleep state recognition can be improved.

The invention discloses an abrasive particle monitoring method and device and electronic equipment, and belongs to the field of monitoring methods, and the method comprises the steps: collecting a to-be-detected signal based on each probe in an electrostatic sensor; performing variational mode decomposition processing on the to-be-detected signal to obtain a target eigenmode function corresponding to the to-be-detected signal; performing sparse representation based on the target eigenmode function to obtain a target signal corresponding to the to-be-detected signal; performing dynamic time warping on each group of target delay signals by using a sliding window to obtain similarity results respectively corresponding to each group of target delay signals; and if a wave crest meeting a preset condition exists in the sequence diagram presented by the similarity result, determining the number of the abrasive particles according to the wave crest, and obtaining an abrasive particle monitoring result. Through the method, the abrasive particle trigger signal is effectively extracted, the interference of abnormal pulses on abrasive particle identification is reduced, and the accuracy of abrasive particle identification is improved.

The invention relates to the technical field of heat exchangers, and discloses a high-heat-exchange-efficiency micro-channel heat exchanger for rail transit, which comprises two symmetrically arranged collecting pipes, a plurality of porous flat pipes and fins are arranged between the two collecting pipes, and bottom plates are arranged on the outermost sides of all the porous flat pipes and the fins. The bottom plate is fixedly installed on the collecting pipe, side plates are further fixed to the end faces of the two sides of each porous flat pipe, and buckle main components are movably arranged in the side plates. The fins are arranged in a corrugated mode, a sliding block is fixed to each wave crest and each wave trough, and a buckle pair component is arranged in each sliding block. The limiting clamping plates are buckled to the side plates, so that the porous flat pipes and the fins are fixedly connected, the problem that welding fixation cannot be disassembled is solved, replacement can be completed only by disassembling the corresponding porous flat pipes or fins during replacement, and the situation that the whole heat exchanger needs to be replaced during replacement due to welding fixation at present is avoided; and the cost is greatly increased.

The invention provides an aluminum foil and a preparation method thereof, the preparation method comprises the following steps: the aluminum foil is subjected to electrochemical corrosion in a mixed acid solution, the half cycle of alternating current adopted by the electrochemical corrosion comprises a plurality of wave crests, and the mixed acid solution comprises at least one of nitric acid and phosphoric acid; passivating the aluminum foil; washing the aluminum foil with water; and the steps of electrochemical corrosion, passivation treatment and water washing are repeated until the aluminum foil reaches the preset corrosion amount. The nitric acid can improve the overall corrosion amount, reduce the surface corrosion of the aluminum foil and promote the longitudinal development of corrosion. Phosphate radicals and aluminum ions can form a complex, so that the concentration of free Al < 3 + > in a hole etching area is reduced, corrosion reaction balance is pushed to move rightwards, and further corrosion is promoted.

The invention provides a single cell structure of a fuel cell and an integrated packaging method thereof, the single cell structure of the fuel cell sequentially comprises an anode plate, one side of the anode plate deviating from a membrane electrode, namely the upper surface of the anode plate, is integrally injected with glue to form a water field sealing element, and the water field sealing element is wave-shaped and comprises a plurality of wave crests and wave troughs which are arranged in sequence; a membrane electrode and a cathode plate; and the adjacent single battery structures are connected through water field sealing pieces. The anode plate, the membrane electrode and the cathode plate respectively comprise a plurality of frames, so that the three layers of polar plates are respectively divided into a plurality of groups of chambers. The waved continuous structure of the water field sealing element provides a longer anti-leakage barrier for the cooling liquid. And the assembly pressing force is uniformly distributed at each contact point at the wave crest, so that the excessive compression of the water field sealing element and the deformation of the polar plate caused by local stress concentration are avoided, and the long-term sealing property is ensured. The multiple groups of chambers share the hydrogen inlet and the air inlet, so that the isolation space required for additionally arranging the inlets can be reduced, and the space of a power generation area is increased.

The present invention relates to the field of filter technology and provides a filter for an automotive air conditioning system. The filter comprises a frame and a filter cloth, the filter cloth being disposed within the frame and having an outer surface comprising an air inlet surface and an air outlet surface connected thereto. The air inlet surface is pleated and includes a plurality of wave crests and a plurality of wave troughs, the plurality of wave crests and a plurality of wave troughs being connected and arranged alternately. Along the arrangement direction of the wave crests and troughs, the apex of adjacent wave crests and the base of adjacent wave troughs can be brought closer or further apart, thereby causing the air inlet surface to fold or unfold accordingly. The present invention enables the filter cloth to be adaptively adjusted according to the actual density of impurities, thereby improving the adaptability of the automotive air conditioning filter.

The invention relates to the technical field of image recognition, in particular to a bridge cable protection layer damage recognition method and system based on machine vision, and the method comprises the steps: extracting a region of interest based on the edge information in a cable protection layer image, obtaining a gray histogram, and carrying out the recognition of the damage of a bridge cable protection layer through the gray value level of a wave crest in the gray histogram; determining a distinguishing value of pixel points in the region of interest; calculating a pixel mutation index of the pixel point by using the gray level change condition of any pixel point in the region of interest in different directions in the local range and combining the distinguishing value of the pixel point; calculating the characteristic value of the pixel point by combining the pixel mutation index of the pixel point and the gray level characteristic in each direction in the local range corresponding to the pixel point; and carrying out damage area identification by utilizing the characteristic values of all the pixel points in the region of interest and combining a machine learning algorithm. According to the invention, the damage identification accuracy of the bridge cable protection layer is effectively improved.

The invention discloses an aircraft surface waviness measurement and analysis method and system, and the method comprises the steps: scanning the surface of an aircraft according to a planned path through employing a three-coordinate measuring machine and a scanning probe, obtaining scanning data, and obtaining the scanning data for evaluation through employing a segmented scanning and segment-to-segment direct splicing mode for a hole, a pin and other structural parts; fitting based on scanning data to obtain a point deviation data set, calculating corresponding point arc length data based on the point deviation data and the point coordinate data on this basis, and drawing a graph by taking a horizontal axis as the point arc length data and a longitudinal axis as the point deviation data; and determining the surface waviness of the airplane by combining the derivative at the intersection point of the point deviation data curve and the transverse axis and the distance between the wave crest and the wave trough, thereby realizing the efficient and accurate measurement of cavities, welding seams and other obstacle structures on the outer surface of a large-scale airplane part or the whole machine and the accurate calculation of the waviness.

The invention relates to the technical field of defect identification, in particular to a braided tube appearance defect detection method and system based on machine vision, and the method comprises the following steps: obtaining an image to generate a brightness fracture region, calculating a peak difference to generate a structure abnormal region, extracting a light spot path to identify a burr abnormal region, and analyzing a grid texture to generate a deformation identification region. And a defect identification scheme is obtained by combining gray scale and jump. According to the method, a brightness fracture area is extracted through gray difference symbol change, segmentation of image jump features is realized, a structure dislocation area is positioned through symmetrical wave crest difference, a form mutation zone is revealed through light spot extension and edge consistency comparison, and burr identification stability is improved. Local trend abnormity is judged through texture length and cross frequency quantification, and a multi-dimensional standard is constructed by combining gray span and disturbance frequency screening, so that defect features are clearly presented in a detail level, and the recognition precision and stability in a complex surface environment are ensured.

The invention relates to the technical field of navigation and positioning, in particular to a pedestrian dead reckoning optimization method based on improved wave crest detection and CNN-LSTM, comprising the following steps: S1, data acquisition: acquiring pedestrian motion sensor data including acceleration, angular velocity and magnetic field intensity through an accelerometer, a gyroscope and a magnetometer; s2, on the basis of an improved wave crest detection algorithm, real-time monitoring and analysis are carried out on the acceleration signal by setting a dynamic threshold value, and an effective gait cycle is extracted; s3, extracting reference features of the step length from the pedestrian motion sensor data, training a step length prediction model of the CNN-LSTM network, and optimizing the step length prediction model; and S4, obtaining a pedestrian course angle based on quaternion attitude calculation, realizing gait cycle segmentation and step length prediction in combination with an improved wave crest detection algorithm and a CNN-LSTM model, and finally calculating the position of the pedestrian at the next moment through the course angle and the step length so as to complete continuous navigation positioning. The method can achieve the dynamic extraction and fusion of the spatial-temporal features of multiple sensors, improves the gait detection robustness and step length estimation precision in a complex scene, remarkably optimizes the overall positioning performance of a PDR, and solves a problem that the positioning precision is reduced because a signal is affected by sensor noise, behavior diversity and the like.