60results about How to "Improve build precision" patented technology

The invention provides an elastic migration seismic wave field construction method and an elastic migration seismic wave field construction device. The method includes computing a finite difference coefficient of extended compact staggered grids according to an elastic wave velocity stress equation; computing a finite difference operator matrix of the extended compact staggered grids; constructing forward direction extrapolation operator of a seismic source wave field, and a reverse-time extrapolation operator of a detection wave field; achieving forward direction extrapolation of a seismic wave field to obtain the seismic source wave field according to the forward direction extrapolation operator of the seismic source wave field, a preset medium model and a preset seismic source function; and achieving reverse-time extrapolation of the seismic wave field to obtain the detection wave field according to the reverse-time extrapolation operator of the detection wave field, a preset medium model and preset multi-component seismic data. Compared with an existing method for constructing an elastic deflection seismic wave field by utilization of a conventional finite difference method and a compact difference method, the number of difference base frame grid points is reduced under the condition of same difference orders, the construction precision of a complex medium wave field can be effectively improved, and therefore the imaging precision of reverse-time migration is improved.

The invention belongs to the technical field of unmanned aerial vehicles, and particularly relates to an unmanned reconnaissance aerial vehicle synchronous positioning and picture compositing method based on a self-adaption EKF. By means of the method, a graph model, a coordinative system, a feature model, an unmanned reconnaissance aerial vehicle movement model and a sensor measurement model of an unmanned reconnaissance aerial vehicle synchronous positioning and picture compositing system are established. Synchronous positioning of the unmanned reconnaissance aerial vehicle and design of a map establishment method frame are achieved through the EKF. The problems that due to the establishment inaccuracy of the unmanned reconnaissance aerial vehicle movement model and an observation model and the linearization of non-linear models, the models are not matched are researched. The uncertainty caused by establishment inaccuracy and linearization errors of the models is modeled into process noise and observation noise of the system with a time-varying mean and a covariance matrix, and the synchronous positioning and picture compositing method based on the self-adaption EKF with a time-varying noise estimator is designed. Statistical features of the process noise and observation of the system are estimated in real time and modified, and therefore model uncertainty is reduced and the estimation progress is improved.

The invention relates to a shallow underwater topography construction method integrating hyper-spectral data and sparse sonar data and belongs to the technical field of underwater topography reconnaissance. According to the shallow underwater topography construction method, dimensions of a hyper-spectral remote sensing image are reduced by aid of a clustering center of sonar data, area division is performed on a low dimensional remote sensing image after dimension reducing, and interpolation is performed on sonar data inside each of the areas to obtain the underwater topography. According to the shallow underwater topography construction method, the hyper-spectral remote sensing image and sparse sonar data are organically combined, in the whole process, and two kinds of data compensate to solve the problem of underwater topography construction well. The remote sensing image and the sonar data are provided with coordinate information after geometric correction, and a certain fuzzy corresponding relation exists between a grayscale of the remote sensing image and the water depth, so that water depth in each depth homogeneous area changes slightly in area-divided remote sensing image, and interpolation results of sonar data are authentic.

The invention belongs to the field of a medium-resolution remote sensing image discrete point DEM (Digital Elevation Model) construction method, which discloses a medium-resolution remote sensing image discrete point DEM construction method based on medium value filtering. The medium-resolution remote sensing image discrete point DEM construction method comprises the following steps of: 1. calculating tidal height information at a satellite imaging moment; 2. dispersing a vector waterline extracted at the satellite imaging moment; 3. combining equidistant tidal level points dispersed in the above steps, building the reference grid of the median filtering according to a remote sensing image resolution ratio, labeling all dispersed equidistant tidal level points, and marking the ID (Identity) of the grid to which the equidistant tidal level points belong; 4. traversing all grids; and 5. on the basis of a median filtering result, building a final DEM result by linear interpolation. In the method disclosed by the invention, the method of median filtering effectively utilizes the elevation information of all discrete points falling in the grids to improve the elevation precision of the discrete point.

The invention discloses an urban ramp driving condition construction method and application. The method comprises the steps: firstly, selecting an urban road containing a ramp as a test route and acquiring speed and slope angle information on the test route; preprocessing the acquired data to obtain effective data, then performing short-stroke division and principal component analysis according tothe effective data, performing short-stroke clustering analysis by adopting an SOM neural network according to a principal component analysis result, screening short strokes according to a clusteringanalysis result, and finally combining the selected short strokes to form an urban ramp driving condition meeting requirements. The related parameters of the ramp are listed into the short-stroke characteristic parameters, and the urban ramp information is contained in the constructed driving working condition so that the constructed driving working condition contains urban ramp driving characteristics and can meet the requirements of an automobile urban ramp driving performance test and can be used as a reference working condition of the automobile urban ramp driving performance test in an automobile bench performance experiment and a performance simulation experiment.

The invention provides a method for synchronously obtaining electric signals of any two ends of a power transmission line. The method comprises the following steps of: collecting electric signals uM(t), iM(t), uN(t') and iN(t') of head and tail ports of the power transmission line; calculating a current calculation value iNj(t) of the tail end of the power transmission line at a t moment by voltage and current collection sequences uM(t) and iM(t) at the front end of the power transmission line according to a power transmission line distribution parameter circuit model; calculating a collection time deviation (t-t') of the two ends of the power transmission line according to the current calculation value iNj(t) of the tail end of the power transmission line at the t moment and a collection current sequence iN(t') of the tail end of the power transmission line at a t' moment; and judging whether a collection moment t' of the tail end of the power transmission line is adjusted or not by comparing with a collection time deviation adjusting setting value delta tset. Circularly, the synchronous collection of the electric signals of any two ends of the power transmission line is realized. The method disclosed by the invention eliminates the influences of inconsistency of transmission delay of a data channel of the power transmission line on synchronous collection of the electric signals; and a time block standard signal except for an electric power system does not need to be introduced so that the microsecond-grade synchronous collection precision of the power transmission line can be realized.

The invention provides a method for constructing an electromagnetic spectrum map, which comprises the following steps of defining the spatial similarity between any two sensors by using a negative square distance, and updating an attraction degree matrix and an affiliation degree matrix through an iterative process so as to determine the clustering center of the sensors; kriging estimation groupsof different unknown points are established through classes of sensors; calculating an experimental variation function for different Kriging estimation groups, fitting theoretical variation functionsin the different Kriging estimation groups, calculating common Kriging weights of measured values of all sensing points in the Kriging estimation groups, and further calculating common Kriging estimated values; repeating the above steps for many times to estimate the observation value of any position where no sensor is arranged in the area, thereby obtaining the distribution condition of the observation value in the whole area, and achieving the construction of an electromagnetic spectrum map. According to the method, affinity propagation clustering is applied to randomly arranged sensor clustering, so that the electromagnetic spectrum map construction precision and construction efficiency are greatly improved.

The invention belongs to the field of electromagnetic spectrum monitoring, and relates to an electromagnetic spectrum map construction method based on ordinary kriging interpolation. The electromagnetic spectrum map construction method based on ordinary kriging interpolation comprises the steps of: (1), calculating an experimental variation function according to an observation value obtained by asensor; (2), fitting the value of the experimental variation function on discrete h; (3), calculating the ordinary kriging weight and the lagrangian multiplier at the position s<o>; (4), calculating an observation value at the position s<o> without the sensor; and (5), repeating the step (1) to the step (4) till an observation value at any position without the sensor in an area is estimated, wherein the distribution condition of the observation values in the whole area is obtained; and electromagnetic spectrum map construction is completed. By means of the electromagnetic spectrum map construction method provided by the invention, a relatively high-precision electromagnetic spectrum map construction result can be obtained under the conditions of the same sensor number and deployment by utilization of the spatial correlation of monitoring data.

The invention relates to an electromagnetic spectrum map construction method and device, computer equipment and a storage medium. The method comprises the following steps: acquiring monitoring data and a to-be-estimated point position, and acquiring path attenuation component estimation by using a trend surface fitting algorithm; subtracting the monitoring data from the path attenuation component estimation value of the corresponding position, performing position clustering on the obtained residual monitoring data, and estimating a clustering result in an optimal neighborhood by adopting a Kriging method to obtain shadow fading component estimation; and obtaining an estimation result according to the path attenuation component and the shadow fading component. Electromagnetic spectrum map construction is decomposed into estimation of path attenuation and shadow fading components, so that the electromagnetic spectrum map construction precision is effectively improved; through monitoring data clustering and optimal neighborhood selection, the calculated amount is reduced under the condition of ensuring the construction precision, and the electromagnetic spectrum map construction speed is effectively improved; and the method does not need prior information such as a radiation source and a propagation model, and has good adaptability.

The invention provides a mobile robot synchronous positioning and map construction method which comprises the following steps: (1) establishment of system models including a robot motion model, an observation model and an environmental characteristic model; conversion of the colored process noise model into a white Gaussian noise model; (2) setting of initial parameters of a mobile robot synchronous positioning and map building algorithm, wherein the initial parameters comprise dead reckoning system parameters and laser radar parameters; (3) state prediction; (4) observing; (5) data association; (6) updating; and (7) state augmentation. The method is characterized by comprising the step (6), in the measurement updating process of standard volume Kalman filtering, an adaptive factor is selected, an autocorrelation covariance matrix and a cross-correlation covariance matrix are adaptively adjusted, the updating process is completed, and meanwhile, the weight ratio between system model prediction information and measurement information can be balanced, so that the positioning precision and the map construction precision are improved.

The invention discloses a skin crushed surface reconstruction method based on characteristics. The method comprises the steps that searching is performed firstly according to the selected technological curved surfaces so that a combined curved surface is acquired; then external contour line of the combined curved surface is extracted and fitting is performed the contour line; a guide line is automatically established according to the complete contour line, and the curved surface is formed via fitting; and whether the curved surface meets the precision requirement is judged, and the curved surface is expanded and extended if the curved surface meets the precision requirement and an expansion surface is established. If precision cannot meet the requirement, precision is doubled and the expansion surface is established again. The expansion surface is cut by the complete contour line, and the maintained curved surface is the reconstructed curved surface. The complete curved surface completely overlapped with the original technological curved surface is reconstructed by the method by aiming at the skin component crushed curved surface, and the complete fitting boundary is obtained so that fitting precision is high, skin mirror image milling numerical control programming can be directly used, processing time is saved, processing efficiency is enhanced and the processing process is enabled to be more stable.

The invention discloses a method and a device for constructing a semantic position history. The method at least comprises the following steps: expanding a certain region outwards based on coordinates of interest points, so as to form an original interaction region; acquiring a moving track of a user; screening staying points in the original interaction region from the moving track according to a construction condition; and assigning semantic information of the interest points corresponding to the staying points to the staying points on the moving track, so as to obtain the semantic position history. Compared with the prior art, the method has the advantages that the manual operation is omitted, or additional equipment does not need to be mounted, so that the technical problems the manual operation is required, and a large number of manpower and material resources are consumed in the prior art are solved, the time and the labor are saved, and the construction precision is further improved.

The invention discloses a method for determining a q-axis current compensation value of a permanent magnet synchronous motor and a pulsation suppression method. The method comprises the following steps: synchronously acquiring a q-axis current feedback signal iq and a rotor position signal theta m, determining a position interval of a rotor based on the theta m, accumulating the interval times by1 and performing synchronous averaging on the iq, and repeatedly acquiring until the accumulated value of the interval times is greater than a threshold value and all the intervals are not overlappedto form a circle of the rotor; performing fast Fourier transform on the synchronous average value corresponding to each interval arranged in sequence to obtain frequency domain characteristic information, determining the amplitude and the phase angle of a to-be-compensated spatial frequency component from the frequency characteristic information, and constructing a q-axis current compensation function; and obtaining a q-axis current compensation value based on the position of the actual compensation moment of the motor rotor and the current compensation function. Time domain information is converted into a space domain, time lag is avoided, the whole process does not affect the dynamic performance of the system, extra devices are not needed, structures and parameters of all control links do not need to be adjusted, and operation is easy.

The invention relates to an automatic library book taking and placing robot based on an ROS. The automatic library book taking and placing robot comprises a movable chassis, a lifting platform, a grabbing device, a multi-grid storage box, a touch screen and a power supply unit. The lifting platform, the multi-grid storage box, the touch screen and the power supply unit are all arranged on the movable chassis, and the grabbing device is arranged on the lifting platform. The power supply unit is in circuit connection with the movable chassis, the lifting platform, the grabbing device, the multi-grid storage box and the touch screen. The robot can create a map in a library, conduct automatic navigation and grab and place targets on all bookshelf layers, manpower and material resources needed by workers for placing books are saved, needed books are automatically found for readers and given to the readers, the time consumed for searching for books is shortened, the reading experience is enhanced, the contact between people in the public place is effectively reduced, and the probability of epidemic disease infection is reduced.

The invention discloses a space tangent vector-based power system static-state voltage stability domain boundary approximation method. The method comprises the following steps of taking ground state power flow as the starting point, adopting a continuous power flow method to search a series of power system saddle-node bifurcation points and tangent vectors thereof, and obtaining boundary points inan active power injection space of a static-state voltage stable domain, namely the saddle-node bifurcation points; based on the space tangent vectors, primarily dividing the static-state voltage stable domain formed by the boundary points into several regions, and calculating the distances from the boundary points to corresponding line sections through a method of bisection, and obtaining a two-dimensional approximation boundary which satisfies certain distance error threshold value requirements; and on the basis of the two-dimensional approximation boundary, establishing a three-dimensionalapproximation boundary according to a triangular establishment principle, then obtaining a triangular approximate plane equation, calculating the maximum distance error from all SNB points in the approximate region corresponding to S triangular approximate planes to the plane, and when the error threshold value is satisfied, completing approximation to obtain a three-dimensional SVSR triangular approximate boundary.

The invention relates to the technical field of automobiles, and particularly discloses a construction method of a load spectrum of an electric automobile speed reducer. The method comprises the following steps: acquiring total pseudo damage D corresponding to an existing load spectrum according to a load coefficient and a torque threshold value of the speed reducer, the maximum design torque Mmax of an input shaft of the speed reducer in the existing load spectrum and other parameter values corresponding to the speed reducer in the existing load spectrum; comparing the total pseudo-damage D corresponding to different existing load spectrums, and determining the basic load spectrum for constructing the new load spectrum, thereby solving the problem that the total pseudo-damage D is not associated with the structure of the speed reducer, enabling the determined total pseudo-damage D to truly reflect the load spectrum intensity of the applicable speed reducer, improving the construction precision of the basic load spectrum, improving the construction precision of the new load spectrum, achieving the effective prediction of the user use condition of the newly developed speed reducer, and ensuring the consistency of the speed reducer bench test and the user test result; moreover, the cost is low, and the period is short.

The invention discloses a three-dimensional reconstruction method based on point-line feature fusion and electronic equipment, and relates to the technical field of image processing, and the method comprises the steps that the electronic equipment can obtain a plurality of images including an object 1, and the plurality of images can be called an image set; each image in the set of images may display an object 1 in different states (e.g., angle, orientation, time, illumination, etc.). The electronic equipment can extract feature points (also called point features) and feature lines (also called line features) from the image set through a specified algorithm, and then the electronic equipment can match the feature points and the feature lines extracted between every two images in the image set. And a three-dimensional model of the object 1 is constructed based on the feature points and the feature lines with the established matching relationship.

The present invention provides a data construction method based on a seismic feature transformation space. The method comprises steps of: Step 1: inputting seismic data that needs to be reconstructed;Step 2: analyzing characteristics of the input seismic data, and determining an effective feature transformation space according to the analysis result; Step 3: performing feature sparse expression on the seismic data according to the feature transformation space by using the corresponding feature transformation; Step 4: performing data construction processing method initialization; Step 5: determining the threshold of each iteration; and Step 6: performing data construction algorithm iterative calculation. The data construction method based on the seismic feature transformation space can automatically select a reasonable and effective feature transformation space according to the geophysical information contained in the actual seismic data itself, and has the adaptability; the method canmeet the transformation requirements of different seismic data, and better realize the sparse expression of the earthquake signal in the feature transformation space; and the method is fast in iterative convergence speed, high in computational efficiency, and high in data construction accuracy.

The invention discloses a method for constructing a comprehensive working condition vibration spectrum of an armored vehicle and a method for constructing a long-life test spectrum of an armored vehicle, and relates to the field of data processing method. The method for constructing the comprehensive working condition vibration spectrum comprises the steps: obtaining a first relation and a second relation among a single working condition actual measurement spectrum, a first reserve coefficient and the comprehensive working condition actual measurement spectrum; obtaining the relation between the first reserve coefficient and the comprehensive working condition actual measurement spectrum according to the first relation and the second relation; training a first RBF neural network to obtain a current first reserve coefficient; obtaining a first relation and a second relation among the single working condition standard spectrum, the second reserve coefficient and the comprehensive working condition standard spectrum; obtaining the relation between the second reserve coefficient and the comprehensive working condition standard spectrum according to the first relation and the second relation; training a second RBF neural network to obtain a current second reserve coefficient; and obtaining a reserve coefficient according to the current first and second reserve coefficients, thereby obtaining an actual comprehensive working condition actual measurement spectrum and a standard spectrum. According to the invention, the accuracy is improved, and a real vibration environment can be simulated more effectively.