Patents
Literature
Patsnap Eureka AI that helps you search prior art, draft patents, and assess FTO risks, powered by patent and scientific literature data.

40 results about "Sum squared error" patented technology

The sum of the squares errors is a measure of the variance of the measured data from the true mean of the data. The sum of the errors is zero, on the average, since errors can be equally likely positive or negative.

Tiny fault detection method based on prediction error sum of squares and JS divergence

The invention discloses a small fault detection method based on a prediction error sum of squares and JS divergence, and relates to the technical field of engineering detection, the algorithm of the application replaces a traditional algorithm for calculating JS divergence based on projection data after PCA dimension reduction, and a probability density function of the prediction error sum of squares of projected data is fitted by using kernel density estimation, so that the detection accuracy is improved. And calculating the JS divergence between different data distributions. The sum of squares of prediction errors reflects parts, which cannot be well reconstructed in the PCA model, of original data points, and the parts may contain abnormal or fault information. According to the method, the fault extraction capability of the prediction error sum of squares in the JS divergence is utilized, so that tiny faults can be better detected. By introducing the time sliding window, the method can more sensitively detect the local abnormal condition causing the increase of the JS divergence value, thereby timely and accurately capturing the process change, providing the early warning about the fault occurrence, and ensuring the safety and reliability of industrial production.
Owner:BEIJING UNIV OF CHEM TECH

Power distribution network traveling wave fault positioning method and related device

The invention discloses a power distribution network traveling wave fault positioning method and a related device, and relates to the technical field of power distribution networks, and the method comprises the steps: collecting a transient signal after a fault at a preset key monitoring point of a power distribution network, extracting an initial traveling wave head from the transient signal, and measuring the moment when the initial traveling wave head reaches other preset monitoring points in the power distribution network, obtaining traveling wave arrival time between the key monitoring point and each monitoring point; the time difference between the traveling wave arrival time is used as the actually measured traveling wave arrival time difference to construct a fault positioning optimization model with the purpose of minimizing the error sum of squares of the theoretical traveling wave arrival time difference and the actually measured traveling wave arrival time difference; and solving the fault positioning optimization model through a pre-constructed chaos particle swarm optimization algorithm to obtain a traveling wave fault positioning result of the power distribution network. The method solves the problems that the positioning effect is not ideal due to the fact that the prior art is prone to falling into local optimum and is poor in adaptability to a complex topological structure, and the convergence speed cannot meet the requirement for rapid power supply recovery.
Owner:ZHONGSHAN POWER SUPPLY BUREAU OF GUANGDONG POWER GRID

Micro thrust dynamic identification method and system

The invention relates to the technical field of micro thrust measurement of spaceflight micro thrusters, and discloses a micro thrust dynamic identification method and system. The recognition method comprises the following steps: constructing a kinetic equation of a thrust measurement system, rewriting the kinetic equation into a state space form, and carrying out integration to obtain a theoretical system response model at any moment; rewriting the theoretical system response model into a numerical model in a step-by-step integral recursion format; constructing an actual system response sequence and constructing an empirical model in combination with the kinetic equation of the thrust measurement system, and rewriting the empirical model; configuring a micro-thrust increment expression, rewriting a numerical model and an empirical model by applying the expression, and further rewriting the numerical model and the empirical model into an augmented form; predicting the prediction output of the future # imgabs0 # moments in the time domain; and a cost function is constructed and solved, so that the sum of squares of errors of predicted output and expected output in an actual system response sequence is minimum, the smoothness of micro-thrust input is considered, and at the moment, predicted micro-thrust corresponding to the predicted output is equal to actually measured micro-thrust corresponding to the expected output.
Owner:PLA PEOPLES LIBERATION ARMY OF CHINA STRATEGIC SUPPORT FORCE AEROSPACE ENG UNIV

Longitudinal aerodynamic parameter identification and calculation method in closed-loop state and large angle-of-attack range

The invention belongs to the technical field of unmanned aerial vehicle aircraft design, and particularly relates to a longitudinal aerodynamic parameter identification calculation method in a closed-loop state and a large angle-of-attack range, and the method comprises the steps: building a flight simulation model; performing aerodynamic characteristic simulation based on a flight simulation model to obtain an aerodynamic load value, comparing the aerodynamic load value with data tested in an actual flight experiment, and calculating and minimizing an error sum of squares; dividing the whole angle-of-attack range into a plurality of sub-intervals, respectively obtaining the optimal aerodynamic parameters of each sub-interval based on the minimum sum of squares of errors, inputting each optimal aerodynamic parameter into the flight simulation model, and carrying out model accuracy verification; and drawing an aerodynamic characteristic curve according to each optimal aerodynamic parameter, and verifying the applicability of the flight simulation model. The method has universality and is suitable for longitudinal aerodynamic coefficient parameter identification of different types of unmanned aerial vehicles, the parameter identification efficiency is improved, and meanwhile the applicability of the model under the complex flight working condition is enhanced.
Owner:XIAN AIRCRAFT DESIGN INST OF AVIATION IND OF CHINA

A method, system, and media of a lightweight indoor 3D laser ground extraction algorithm

The application discloses a lightweight indoor 3D laser ground extraction algorithm method, system and medium. The method comprises the following steps: acquiring indoor 3D laser radar data; obtaining coordinate values based on a laser radar coordinate system according to the indoor 3D laser radar data; sending the coordinate values to a preset plane equation to obtain a ground plane normal vector; sending the ground plane normal vector to a first preset coordinate system to establish a constraint to obtain a comprehensive error value; and accumulating squares of values in the comprehensive error value to obtain a comprehensive error sum of squares; extracting a minimum value in the comprehensive error sum of squares, and setting a coordinate point corresponding to the minimum value as an optimal current pose. The application is suitable for various lasers, and by giving a preset threshold, whether it is 16 lines, 32 lines or 128 lines, the algorithm accuracy and robustness are ensured, and the accuracy of recognized ground points is improved.
Owner:GUANGZHOU GOSUNCN ROBOTICS CO LTD

A ship type classification prediction method and system based on K-means and XG-Boost

The application provides a ship type classification prediction method and system based on K-means and XG-Boost, acquires ship data and carries out pretreatment, then adopts a K-means clustering algorithm to respectively cluster each kind of data in the pretreated ship data to obtain multiple clusters, calculates error sum of squares of all data in each cluster, calculates the classification number of each kind of data according to the error sum of squares, selects a certain classification number by using an elbow method, marks the ship type of all clustered ships according to the classification number, then takes the ships with marked ship types as training set samples, adopts an XG-Boost classification algorithm to train the training set samples to obtain multiple classification prediction models, verifies the multiple classification prediction models to obtain an optimal classification prediction model, and predicts the ship types of all ships in the world according to the optimal classification prediction model and marks the ship types. The application can accurately classify all ships in the world, and can avoid overfitting and underfitting of the model while ensuring the accuracy.
Owner:COSCO SHIPPING TECH CO LTD +1

A heat supply station heat supply area heat network data visualization monitoring method and system

This invention discloses a data visualization monitoring method and system for heating networks in heating station supply areas, specifically relating to the management field. The method includes synchronously collecting multi-dimensional data, establishing a heating network spatial coordinate system to locate the data collection nodes, and storing the coordinate data in a data storage center. It employs a K-means clustering algorithm to extract three typical heating patterns and simultaneously evaluates the matching degree of user heating patterns. An optimization cycle is set to extract optimized samples, and the gradient descent method is used to minimize the sum of squared errors between model predictions and actual values, updating relevant model parameters. Based on data analysis results, this invention generates three targeted decision-making suggestions: resource allocation, inspection priority, and heating guidance. Combined with historical data tracing and operational pattern mining, it provides comprehensive support for short-term operational optimization and long-term planning of the heating network, effectively improving the efficiency of heating resource utilization, reducing operational risks, and minimizing resource waste, thus exhibiting significant economic and management benefits.
Owner:HUBEI ENERGY OPTICS VALLEY THERMAL CO LTD

Servo system reliability evaluation method based on K-S test

The invention discloses a servo system reliability evaluation method based on K-S test. The method comprises the following steps: based on a fault data set of a servo system, performing K-S test by using an empirical distribution function and a fault probability distribution function of a Weibull distribution model; and if the K-S test is not passed or the end condition of the particle swarm algorithm is not satisfied, updating the position of each particle in the state search space through the particle swarm algorithm, outputting the current parameter of the Weibull distribution model, updating the Weibull distribution model by using the current parameter, and returning to the step of performing the K-S test. According to the method, the maximum difference of individuals is concerned in the K-S test, the particle swarm algorithm takes an error sum of squares function as a target function, the error of the whole is concerned to be minimum, the two functions are combined, the parameters of the solved Weibull distribution model are more accurate, and the convergence speed is higher through the particle swarm algorithm.
Owner:ARMY ENG UNIV OF PLA

Method for identifying and calculating longitudinal aerodynamic coefficient in open-loop state large angle-of-attack range

The invention belongs to the technical field of unmanned aerial vehicle design, and particularly relates to an open-loop state large-angle-of-attack range longitudinal aerodynamic coefficient identification calculation method, which comprises the following steps of: comparing simulation data with test data in an actual flight test, calculating an error sum of squares of the simulation data and the test data, and minimizing the error sum of squares; dividing the whole attack angle range into a plurality of sub-intervals, respectively obtaining the optimal aerodynamic parameters of each sub-interval based on the minimum sum of squares of errors, inputting each optimal aerodynamic parameter into the flight simulation model, comparing the optimal aerodynamic parameters with test data for verification, and executing the next step when the difference value between the optimal aerodynamic parameters and the test data is within a set range; and drawing an aerodynamic characteristic curve according to each optimal aerodynamic parameter, verifying the applicability of the flight simulation model, and optimizing the robustness of the flight simulation model. The method is suitable for longitudinal aerodynamic coefficient parameter identification of different types of unmanned aerial vehicles, the parameter identification efficiency is improved, and meanwhile the applicability of the model under the complex flight working condition is enhanced.
Owner:XIAN AIRCRAFT DESIGN INST OF AVIATION IND OF CHINA

Tunnel unmanned aerial vehicle cluster mobile ad hoc network and navigation method and system in closed space

The invention relates to a tunnel unmanned aerial vehicle cluster mobile ad hoc network and navigation method and system in a closed space. Determining the number of unmanned aerial vehicles most suitable for covering the current ground user group and the target position of each unmanned aerial vehicle by adopting a clustering algorithm based on error sum of squares and contour coefficient value optimization so as to realize an unmanned aerial vehicle cluster mobile ad hoc network; and a dynamic adaptive potential field algorithm based on multi-agent reinforcement learning is adopted to plan an air route for each unmanned aerial vehicle to arrive at the corresponding target position. According to the method, the coverage range and the service quality of the unmanned aerial vehicle system are effectively improved, and efficient path planning is realized in a dynamic and complex environment.
Owner:STATE GRID JIBEI ELECTRIC POWER CO LTD TANGSHAN POWER SUPPLY CO +2

Cross-validation training method, device and equipment for large-scale flow field proxy model

The present application relates to a cross-validation training method, apparatus, and equipment for a large-scale flow field proxy model. The method comprises: determining the range of design variables and performing normalization processing; performing a recursive permutation evolution experimental design on the design variables, generating sample points, and performing numerical simulation to obtain flow field data as the response values of each node in the flow field; constructing a proxy model for each node in the large-scale flow field, and calculating the corresponding basis function matrix of the proxy model based on the same shape parameters; calculating the sum of squared cross-validation errors for the entire flow field by constructing a second intermediate matrix related only to the shape parameters and design variables and a global matrix related only to the node response values, and optimizing the shape parameters with minimizing the sum of squared errors as the optimization goal, until convergence and output of an optimal proxy model based on the optimal shape parameters to perform the flow field prediction task. This method can achieve rapid and reliable verification of large-scale flow field proxy models and efficient and accurate flow field prediction.
Owner:NAT UNIV OF DEFENSE TECH

A privacy protection recommendation method and system based on matrix decomposition

The application relates to a privacy protection recommendation method and system based on matrix decomposition and belongs to the technical field of privacy protection recommendation. The method comprises the following steps: obtaining a historical rating matrix of a user; performing matrix decomposition on the historical rating matrix to obtain a shared rating matrix; sending the shared rating matrix and a scored item set to a recommendation server to generate public parameters, a decomposition matrix and a shared value of the decomposition matrix; generating inner product triplets and multiplication triplets by using a triplet server; calculating errors between real ratings and predicted ratings by using the recommendation server to generate an error shared matrix; optimizing the error shared matrix until the error squares of all the error shared matrices are less than a threshold value; calculating partial derivatives of a loss function on the decomposition matrix to obtain a gradient shared matrix; updating the decomposition matrix to obtain a user decomposition shared matrix; and generating a privacy protection recommendation result of the user by using the user decomposition shared matrix. The application provides strong protection in the aspect of protecting user privacy.
Owner:CHINA TELECOM DIGITAL INTELLIGENCE TECH CO LTD

Two-dimensional recursive filter design method based on improved particle swarm optimization algorithm

The invention belongs to the field of circuits and systems, and particularly relates to a two-dimensional recursive filter design based on an improved particle swarm optimization algorithm. Comprising the following steps: 1) performing mathematical analysis on a transfer function of a two-dimensional recursive filter to establish a model; 2) finding out an optimal parameter set by using an improved particle swarm optimization algorithm, and enabling the sum of squares of errors between the amplitude response of the designed filter and the amplitude response of an ideal filter to be minimum; 3) integrating a dynamic inertia weight strategy, a dynamic learning factor and a prying strategy into a particle swarm optimization algorithm; 4) setting algorithm operation parameters; and 5) by minimizing the objective function, obtaining a parameter set and combining the parameter set with a filter model structure to form an optimal two-dimensional recursive digital filter meeting conditions. According to the scheme, the stability of the filter can be ensured, and compared with the previous scheme, the amplitude response of the two-dimensional recursive digital filter is closer to that of an ideal two-dimensional recursive digital filter.
Owner:NANJING TECH UNIV

Small hydropower station cluster planning and grouping method, equipment and medium

The invention relates to the technical field of power systems and renewable energy scheduling, and discloses a small hydropower station cluster planning and grouping method and device and a medium, and the method comprises the steps: obtaining multi-source data of each small hydropower station, and constructing a small hydropower station cluster feature space model; constructing a mathematical effectiveness index and a field rationality index, and establishing a k-means clustering algorithm multi-dimensional evaluation index system; executing an improved k-means + + clustering algorithm, and generating clustering schemes and evaluation results under different K values; constructing a derivative evaluation index based on an error sum of squares, distributing an index weight, calculating a comprehensive score corresponding to each K value, and determining an optimal clustering k value; and outputting a small hydropower station cluster grouping scheme corresponding to the optimal clustering number. According to the method, adaptive grouping of small hydropower station clusters is realized through a clustering algorithm driven by a small amount of data, and a small hydropower station cluster division scheme with reasonable spatial distribution, unified basin attributes and coordinated operation characteristics is provided for regional power grid dispatching.
Owner:GUIZHOU POWER GRID CO LTD

Missing Load Recovery Method Based on Similar Block Chimerism and First-Order Polynomial Interpolation

The present invention discloses a method for restoring missing load based on similar block chimerism and first-order polynomial interpolation. First, the load data of power users is collected and a third-order load tensor is constructed. According to the position of the missing load, a matching similar block offset is constructed, and the matching similar block offset is specifically the offset between the position of the missing load and the position of the matching similar block. The matching similar block is selected by the spreading rule and irregular search optimization, and the sum of the squared errors between the matching similar block and the data block at the missing load position is used as the selection criterion, and the optimal similar block is used to generate preliminary restored data. First-order polynomial interpolation is performed on the load data at the missing position of the unfolded tensor to construct auxiliary restored data. The preliminary restored data and the auxiliary restored data are combined to obtain the final result of restoring the missing load. The method proposed by the present invention helps to fully explore the characteristics of the load data itself, and has certain practical significance for realizing the restoration of randomly missing user load data.
Owner:ZHEJIANG UNIV

Improved deformable block registration method based on historical information correction

A deformable block registration improvement method based on historical information correction comprises the steps that an image is layered according to scenery information, and key areas are marked according to application requirements and a layering result; random block selection and deformation calculation in the key area: randomly selecting blocks in the key area, adjusting the size of the selected blocks, and calculating an initial deformation matrix of the selected blocks by adopting a normalized error sum of squares and an affine model; correcting a deformation result based on a historical deformation field: constructing historical deformation field data, extracting historical deformation data of the current block, and correcting an initial deformation matrix through a dynamic weight model; and performing new deformation field fitting: applying consistency constraint to the correction block, fitting a global deformable field by adopting thin-plate spline interpolation, outputting after filtering optimization, and updating a historical deformation field database. According to the method, the problems of low registration precision and error accumulation of deformable blocks in a multi-moving-target scene are solved through marking key areas by image layering, performing targeted random block selection, performing historical deformation field correction and performing consistent deformation field fitting.
Owner:BEIJING RES INST OF SPATIAL MECHANICAL & ELECTRICAL TECH

Power system state estimation Hessian matrix method based on optimal control

The invention discloses a power system state estimation Hessian matrix method based on optimal control, and belongs to the technical field of power system state estimation. According to the method, a node power equation for state estimation of the alternating-current power distribution network is established, and a Jacobian matrix and a Hessian matrix of node power unbalance to node voltage and phase angle are deduced; a state estimation optimization model with the minimum sum of squares of node power measurement errors as a target is constructed, the power system state estimation Hessian matrix method based on optimal control is provided, the state estimation convergence is improved, meanwhile, the calculation speed is guaranteed, and compared with a traditional Newton-Raphson state estimation method, the method has the advantages that the calculation speed is improved, and the calculation efficiency is improved. The state estimation method is few in iteration times and good in convergence.
Owner:SHANDONG UNIV OF SCI & TECH

Railway subgrade settlement prediction method based on IGM-PSVR model

The present invention discloses a railway subgrade settlement prediction method based on the IGM-PSVR model. First, the subgrade settlement data is collected and preprocessed. Then, the data is subjected to a level ratio check, a corresponding differential equation is established, and the time response function is solved. The background value of the gray model is further optimized, and an improved gray model IGM(1,1) is constructed to obtain the prediction results of the model. Then, the particle swarm optimization algorithm is used to optimize the hyperparameters of the support vector regression (SVR) model, and a particle swarm optimized support vector machine model is constructed to obtain the prediction results of the model. Finally, the inverse sum of squared errors method is used to assign different weights to the two-step prediction results, and finally the combined prediction results are obtained. Experiments show that the combined model has higher prediction accuracy than the single model, can better reflect the trend of subgrade settlement changes, and plays an important role in ensuring the safety of railway transportation.
Owner:LANZHOU UNIV OF ARTS & SCI

A laser galvanometer automatic focusing method based on polynomial regression algorithm

ActiveCN120669383BAlgorithmGalvanometer
This invention relates to an automatic focusing method for laser galvanometers based on a polynomial regression algorithm, including variable definition, data collection of sample data within different power ranges from 10% to 80%, and data preprocessing; employing a piecewise polynomial regression model, and adding an L2 regularization term to the model to prevent overfitting; and minimizing the observed value D. i The model parameters are estimated using the sum of squared errors between the predicted and actual values. The model is used to predict values ​​in real time. When the absolute value of the deviation ∈ between the predicted and actual roundness values ​​D exceeds the threshold Th, the galvanometer height H or laser power P is dynamically adjusted to make D approach the target value D. target =0; the system is based on the optimal height H * The Z-axis position of the galvanometer is adjusted in real time to focus the laser beam at the optimal position; the deviation between the actual value D and the predicted value ∈ is periodically collected to update the regression model coefficients. This invention enables precise focusing of the laser beam, improving product consistency and yield.
Owner:NINGDE SKEQI INTELLIGENT EQUIP CO LTD

Linear and arc combined convex optimization method for cylindrical roller

The invention relates to a straight line and circular arc combined convex shape optimization method for a cylindrical roller, and aims to solve the problems that in existing logarithmic shape modification fitting, circular arc segmentation connection points depend on experience setting, and adaptability is poor. According to the method, a corresponding line-arc combination curve model is constructed based on a logarithmic modification curve, and the line-arc combination curve is iteratively optimized through an optimization method to obtain an optimal line-arc combination curve, so that the optimal line-arc combination curve approaches the logarithmic modification curve. The modeling process comprises segmentation point setting, connection point generation, arc parameter solving and curve construction, the optimization target is to minimize fitting error quadratic sum, and the geometric rationality and convexity of the curve are constrained and guaranteed. The adopted optimization algorithm is a sequence least square quadratic programming (SLSQP) algorithm. According to the method, fitting precision and engineering applicability are remarkably improved, and the method has good universality and expansibility, is suitable for modification design of various roller bearings and has engineering application value.
Owner:DALIAN UNIV OF TECH

Dynamic injection posture adjusting method based on fry size information

The invention discloses a dynamic injection posture adjustment method based on fry size information, and relates to the technical field of aquaculture, and the method comprises the steps: carrying out the image collection of a fry injection region, and carrying out the preprocessing of the collected image; identifying fry size information according to the preprocessed fry image; establishing a mathematical model between the injection parameter and the fry size according to the fry size information, and calculating to obtain a predicted fry injection parameter according to the mathematical model; calculating to obtain an injection parameter error sum-of-squares function according to the predicted fry injection parameters in combination with the injection angle under the optimal injection effect; planning a movement track of an injection needle by utilizing a path planning algorithm, and predicting a fry injection position by combining the movement speed of the fry; according to the predicted fry injection position and the actual fry position, fry injection accuracy is calculated, and the injection posture is dynamically adjusted in combination with the injection angle error. According to the invention, the injection accuracy and efficiency are improved, the damage to fish fries is reduced, and the automation level of the production process is improved.
Owner:ZHEJIANG ELECTROMECHANICAL VOCATIONAL & TECH COLLEGE

Closed-loop identification method and device based on nuclear power steam generator model, terminal equipment and storage medium

The application discloses a kind of closed loop identification method, device, terminal equipment and storage medium based on nuclear power steam generator model, by adopting autoregressive model structure, according to several historical operation data, the initial system model of nuclear power steam generator is structured, then least square method and auxiliary variable method are used, to determine the observation variable in initial system model, to be identified parameter, residual error and the parameter initial value of to be identified parameter, therefore, the present application can overcome the nonlinear problem when the nuclear power steam generator is modeled at present, and the problem of low quality of closed loop operation sampling data of nuclear power steam generator.Finally, by minimizing the way of prediction error square sum, the iteration model parameter is updated using prediction error method, effectively improve parameter identification precision, finally obtain the target value of to be identified parameter, to build the system coupling model that can be used to carry out real-time monitoring and control to the operating state of steam generator.
Owner:SHENYANG INST OF AUTOMATION GUANGZHOU CHINESE ACAD OF SCI

A robot joint friction model parameter identification method, device and equipment

The application provides a robot joint friction model parameter identification method, device and equipment. The method provided by the application comprises the following steps: a speed-related friction model, a temperature-related friction model and a load-related friction model are established to constitute a robot joint friction model; a plurality of groups of friction characteristic data of a robot joint in different working states are acquired, and initial value ranges of various parameters in the model are set based on expert knowledge and prior physical knowledge to constitute an initial parameter search space; an error square sum of model prediction is taken as a fitness function, the initial parameter search space is optimized based on the plurality of groups of friction characteristic data by using a genetic algorithm to obtain a candidate parameter search space; and an optimization function with the optimization objectives of minimizing a prediction error and minimizing a parameter physical deviation is constructed for the robot joint friction model.
Owner:BEIHANG UNIV

Laser galvanometer automatic focus searching method based on polynomial regression algorithm

The invention relates to a polynomial regression algorithm-based automatic focus searching method for a laser galvanometer, which comprises the following steps of: defining variables, acquiring sample data in different power sections within 10-80%, and preprocessing the data; a piecewise polynomial regression model is adopted, and an L2 regularization item is added into the model in order to prevent the model from being over-fitted; estimating model parameters by minimizing the sum of squares of errors between the observed value Di and the predicted value; when the absolute value of the deviation epsilon between the predicted value and the actual roundness value D exceeds a threshold value Th, dynamically adjusting the galvanometer height H or the laser power P to enable D to approach a target value Dtarget = 0; the system adjusts the Z-axis position of the galvanometer in real time according to the optimal height H *, so that the laser beam is focused at the optimal position; and periodically collecting a deviation epsilon between an actual value D and a predicted value, and updating a regression model coefficient. According to the invention, the laser beam can be accurately focused, and the consistency and the yield of products are improved.
Owner:NINGDE SKEQI INTELLIGENT EQUIP CO LTD

A method for selecting full-cycle natural ground motion records

ActiveCN119087515BSeismic signal processingGreedy optimizationComputational physics
The present invention relates to the field of earthquake engineering technology, and in particular to a method for selecting full-cycle natural earthquake records, comprising the following steps: S100. Evaluating the intensity, design grouping, and site category of a proposed building site, and screening earthquake records according to the corresponding magnitude, epicenter distance, and equivalent shear wave velocity of the site; S200. Using the spectrum value of the standard response spectrum as the target mean and the standard deviation as the variable to generate a simulation spectrum, the uncertainty of the earthquake record is reflected by the uncertainty of the standard deviation, for each simulation spectrum, a record with a similar response spectrum is selected, the similarity between the earthquake response spectrum and the simulation spectrum is evaluated using the square sum of errors (SSE), and the first N records with the smallest SSE are selected; S300. The mean value and standard deviation of the simulation spectrum will approximately match the corresponding target value, and the record obtained in step S200 is improved by a greedy optimization method; S400. Determine the optimization variable and determine the range interval of each parameter; S500. Output the final optimization parameters and the selected record results.
Owner:CHONGQING UNIV

Longitudinal aerodynamic parameter identification and calculation method in small angle-of-attack range in closed-loop state

The invention belongs to the technical field of unmanned aerial vehicle design, and particularly relates to a longitudinal aerodynamic parameter identification calculation method under a closed-loop state and a small attack angle range, and the method comprises the steps: simulating the flight state change process of an unmanned aerial vehicle under the condition of the closed-loop state and the small attack angle range based on a flight simulation model; dynamic characteristics of the aircraft under different longitudinal pneumatic conditions are obtained; performing parameter identification calculation on the dynamic characteristics of the aircraft under different longitudinal pneumatic conditions to obtain flight simulation data; iterative optimization is performed on the longitudinal aerodynamic model parameter combination set through a genetic algorithm, and an optimal longitudinal aerodynamic model parameter combination is obtained by combining the sum of squares of errors between flight simulation data and actual flight test data; and simulation verification and error analysis are carried out on the optimal longitudinal aerodynamic model parameters, and verification is completed when a preset precision requirement is met. The influence of the control law on the flight test in the flight process is considered, and the identification of the longitudinal aerodynamic coefficient parameters in the corresponding closed-loop state is more accurate.
Owner:XIAN AIRCRAFT DESIGN INST OF AVIATION IND OF CHINA

A wind power output clustering method and system based on a DTW-Kmedoids algorithm

The application discloses a wind power output clustering method and system based on a DTW-Kmedoids algorithm, relates to the technical field of wind power output scene generation, and comprises the following steps: interpolating, reducing the dimension, normalizing and smoothing processing of wind power historical data; adopting a dynamic time warping (DTW) algorithm to perform distance measurement, adopting a Kmedoids clustering algorithm to perform iteration, obtaining a clustering result, and outputting the center curve of each cluster; calculating the error sum of squares of each cluster for the clustering results of different cluster numbers, and adopting an elbow rule to determine the optimal cluster number; generating a typical wind power output scene curve according to the clustering result under the optimal cluster number, and establishing a clustering effect evaluation index system. The application introduces the dynamic time warping distance algorithm, can adapt to the nonlinear change of the wind power output curve, improves the accuracy of similarity measurement through dynamic matching of time series, makes the generated typical scene more representative, makes the clustering center point more representative, and further makes the stability of the generated wind power output scene better.
Owner:GUIZHOU POWER GRID CO LTD

Method and device for clustering and evaluating operation modes of power system

The invention discloses a clustering and evaluation method and device for operation modes of a power system. The method comprises the following steps: carrying out dimensionality reduction feature extraction on actual power flow section operation data of a power system by adopting a principal component analysis method to obtain dimensionality reduction feature data; determining the optimal clustering number of the operation mode of the power system by adopting an elbow rule of a contour coefficient and an intra-cluster error sum of squares; performing clustering analysis on the dimension reduction feature data according to the optimal clustering number to obtain a clustering result of the operation mode of the power system, the clustering result being used for representing a typical operation mode of the power system; and evaluating the clustering result according to the contour coefficient distribution of each sample point in the dimension reduction feature data and the average contour coefficient, and determining an evaluation result of the clustering result.
Owner:CHINA ELECTRIC POWER RESEARCH INSTITUTE CO LTD +1

Cavity blade tip gap measurement method and system based on multi-peak Gaussian fitting

The invention discloses a multi-peak Gaussian fitting concave cavity blade tip gap measurement method and system, and belongs to the technical field of concave cavity blade tip gap measurement, and the multi-peak Gaussian fitting concave cavity blade tip gap measurement method comprises the steps: S1, obtaining an analog voltage signal reflecting the size of a blade gap; s2, establishing a double-Gaussian model of the concave cavity blade; s3, establishing an error sum of squares model; and S4, parameters in the error sum of squares model are adjusted by using an iterative algorithm, and an iteration termination condition is that the error sum of squares is smaller than a preset threshold, and the obtained parameter value is the parameter of the double-Gaussian model. By the adoption of the technical scheme, the double-Gaussian model and the error quadratic sum model are utilized, and the blade tip clearance of the concave cavity blade can be measured rapidly and accurately.
Owner:SHANCE (TIANJIN) TECH CO LTD

Sawing method and system of high-speed circular sawing machine based on least square method

The invention relates to a high-speed circular sawing machine sawing method and system based on a least square method, and the method comprises the following steps: S1, collecting the non-uniform point cloud data of the edge of a workpiece through a laser scanner, and generating a workpiece edge discrete sampling point set containing N three-dimensional coordinate points; s2, performing segmented cubic spline interpolation processing on the discrete sampling point set to generate a continuous and derivable cutting reference curve; s3, a mathematical model with the sum of squares of the notch track errors as a target function is constructed, the saw blade rotating speed n, the feeding speed v and the sawing depth d serve as optimization variables of the model, and sawing force F is introduced to serve as a constraint condition; s4, on the basis of the mathematical model and the cutting reference curve, the saw blade rotating speed n, the feeding speed v and the sawing depth d are adjusted through an iterative algorithm, the sum of squares of cut track errors is converged under the condition that the constraint condition of sawing force F is met, and an optimal technological parameter combination (n, v and d *) is obtained; and S5, controlling the saw cutting blade to work according to the optimal process parameter combination.
Owner:ZHEJIANG MINGHE STEEL PIPE CO LTD