Patents
Literature
Patsnap Copilot is an intelligent assistant for R&D personnel, combined with Patent DNA, to facilitate innovative research.
Patsnap Copilot

87 results about "Multicollinearity" patented technology

In statistics, multicollinearity (also collinearity) is a phenomenon in which one predictor variable in a multiple regression model can be linearly predicted from the others with a substantial degree of accuracy. In this situation the coefficient estimates of the multiple regression may change erratically in response to small changes in the model or the data. Multicollinearity does not reduce the predictive power or reliability of the model as a whole, at least within the sample data set; it only affects calculations regarding individual predictors.

Comprehensive electric energy meter verification method and system based on improved least square method

The invention discloses a comprehensive electric energy meter verification method and system based on an improved least square method. The method comprises the steps: generating a scatter diagram of original data, deleting an abnormal value, and obtaining sample data; carrying out Pearson correlation analysis and VIF inspection on independent variables in the sample data; determining a multi-colinearity existence range between the independent variables; checking the multiple collinearity by fitting a sample error average regression line and a median regression line; performing multivariate regression analysis according to an inspection result, and preliminarily determining a regression equation; checking the credibility of the regression equation, and determining a data regression model; correcting the data regression model through residual analysis; and normalizing the weight of each variable, calculating an influence weight of each variable on the error, and substituting the influence weight into the data regression model to carry out comprehensive verification on the electric energy meter. According to the invention, whether the metering error of the electric energy metering device exceeds a standard specified range can be effectively verified, and the reliability and stability of the electric energy metering device are ensured.
Owner:ELECTRIC POWER RESEARCH INSTITUTE OF STATE GRID SHANDONG ELECTRIC POWER COMPANY +1

Modeling method of urban electrical network distribution transform weight overload mid-term forewarning model

The invention relates to a modeling method of an urban electrical network distribution transform weight overload mid-term forewarning model. The forewarning model is established according to the following steps of firstly, collecting original data of correlated variables required for modeling, and cleaning the original data so that the quality of data entering the forewarning model can be ensured; secondly, designing and calculating characteristic variables of the forewarning model, screening the characteristic variables, and establishing a judgment basis for testing the multicollinearity among independent variables; thirdly, establishing one forewarning model on the basis of Logistic regression and through a stepwise regression method, and then judging whether the multicollinearity exists among the independent variables of the model or not so as to judge whether the model can be used or not; fourthly, repeatedly executing the second step and the third step so that the characteristic variables can be calculated again, and establishing various different forewarning models, evaluating the established forewarning models, and then comparing the evaluation parameters of all the forewarning models to determine the optimal forewarning model; fifthly, outputting the optimal forewarning model. By means of the method, the accurate distribution transform weight overload mid-term forewarning model can be easily established.
Owner:STATE GRID CORP OF CHINA +3

Aeromagnetic compensation method based on major constituent analysis

The invention discloses an aeromagnetic compensation method based on major constituent analysis. The method comprises steps that major constituents of a standard attitude matrix of calibration flight are calculated; the major constituents of the standard attitude matrix of the calibration flight are ordered according to contribution degrees, and multiple major constituents with relatively high contribution degrees are selected to acquire a new attitude matrix and a transformation matrix of the calibration flight; calibration flight data is utilized, the least square algorithm is utilized to acquire a compensation coefficient under the new attitude matrix; according to the transformation matrix of the calibration flight, major constituents of a standard attitude matrix of verification flight are extracted to acquire a new attitude matrix of the verification flight; magnetic compensation for measurement data of the verification flight is carried out, and aeromagnetic compensation based on major constituent analysis is realized. The method is advantaged in that problems of information overlapping caused by multicollinearity and inaccurate magnetic compensation caused by unstable inverse matrix solution existing in the prior art are effectively solved, the system information and noise can be effectively distinguished, system modeling accuracy is improved, and effective compensation of an aeromagnetic field is realized.
Owner:INST OF ELECTRONICS CHINESE ACAD OF SCI

Traffic accident prediction method based on hybrid geographically weighted regression

PendingCN111210052AOvercoming the problem of low prediction accuracyHigh precisionForecastingResourcesTraffic crashSpatial heterogeneity
The invention belongs to the technical field of traffic safety, and particularly relates to a traffic accident prediction method based on hybrid geographically weighted regression, which comprises thefollowing steps: step 1, dividing a spatial research area of a traffic accident, and collecting influence factor data; 2, explaining variables through multiple colinearity verification, and deletingunreasonable explaining variables; step 3, constructing a space weight function as a Gaussian function and a double square function; 4, determining that the bandwidth selection type is a fixed bandwidth and an adaptive bandwidth, and determining that a bandwidth optimization criterion is a corrected red pool information criterion; step 5, constructing and determining an optimal geographically weighted Poisson regression model; step 6, respectively bringing in explanatory variables as global variables to construct a hybrid geographically weighted Poisson regression model to perform a comparisontest; and step 7, constructing and determining an optimal hybrid geographically weighted Poisson regression model. The invention provides a traffic accident prediction method based on hybrid geographically weighted regression, which is sufficient in spatial heterogeneity consideration and high in prediction model precision.
Owner:TIANJIN UNIV OF TECH & EDUCATION TEACHER DEV CENT OF CHINA VOCATIONAL TRAINING & GUIDANCE

Method for measuring magnetic field noise coefficients of underwater vehicle based on small signal method

The invention belongs to the field of engineering magnetic field modeling, and provides a method for measuring the magnetic field noise coefficients of an underwater vehicle based on a small signal method, and the method comprises: an UUV (Unmanned Underwater Vehicle) background magnetic field model is built; a magnetic field vector of UUV measuring environment is measured in advance; the placement direction of an UUV is changed, and corresponding Hx1, Hx2, Hx3 and Hx4 are measured through the changes of large-angle attitudes; the other conditions are not changed, a vertical direction magneticfield is applied to the UUV, and the rolling angle and the pitching angle are kept to be zero, the pointing orientation of the UUV is changed horizontally, and Hx5, Hx6, Hx7 and Hx8 are respectivelymeasured through the changes of the large-angle attitudes; a constant magnetic field, an induction magnetic field coefficient and a geomagnetic field are calculated, the above steps are repeated, andother parameters of the UUV magnetic field are calculated. According to the method, the correlation between the noise coefficients of the magnetic field and the multicollinearity of the model are effectively reduced, the influence on the energy spectrum of useful signals in the magnetic field is avoided, and the subsequent detection and identification of weak useful signals are facilitated.
Owner:THE PLA NAVY SUBMARINE INST

Forest biomass-based remote sensing image feature selection method and apparatus

The present invention provides a forest biomass-based remote sensing image feature selection method and a forest biomass-based remote sensing image feature selection apparatus. The method includes the following steps that: feature values are extracted from a forest remote sensing image, the feature values are preprocessed through an SR (stepwise regression) algorithm, and feature values corresponding to multicollinearity are removed from the preprocessed feature values, so that a feature set can be generated, the initial set of the feature set is a full set; the feature set is updated repeatedly according to the following processes: an SVM (support vector machine) algorithm is trained according to the initialization feature set, so that the weights of feature values in the initialization feature set are determined, an SVM-REF (support vector machine-recursive feature elimination) algorithm and the weights are adopted to construct the feature sequencing coefficient of the feature values in the feature set, and the feature values in the feature set are sequenced according to the feature sequencing coefficient, and the feature set is updated according to the sequence of the feature set; and update operation is carried out continuously until the number of feature values in the current feature set is equal to a preset number of feature values, and the current feature set is determined as the optimal feature set used for forest biomass. With the method and apparatus of the invention adopted, the effect of remote sensing image feature selection can be optimized.
Owner:LIANYUNGANG TECHN COLLEGE +1

Multivariate robust soft measurement method about sewage treatment effluent quality index

ActiveCN110320335AMulticollinearity enhancementImprove collinearityTesting waterNeural architecturesHysteresisAutomatic control
The invention provides a multivariate robust soft measurement method about sewage treatment effluent quality index, and relates to the technical field of the sewage treatment automatic control. The method comprises the following steps: taking a parameter real-time measured by conventional detection equipment based on industrial field as input data of a model; establishing a random weight neural network model capable of simultaneously performing multivariate dynamic prediction on the main parameters for balancing the sewage treatment effluent quality, thereby realizing robust soft measurement of BOD content, COD content, TSS content sewage quality parameters, and comprehensively describing the sewage quality parameters, thereby avoiding the hysteresis of the offline assay and the uncertainty of the manual operation. The sparse partial least square and Schweppe type general M are utilized at the same time so as to eliminate the influence on the modelling by multiple colinear and reduce the bad influence on the modelling by outlier and leverage point in the data; and meanwhile, the aim of variable selection is reached, and an estimation value of the multivariate sewage treatment effluent quality parameter at the specified dynamic time zone can be given more accurately.
Owner:NORTHEASTERN UNIV

Software failure time forecasting method based on kernel partial least squares regression algorithm

InactiveCN103093094AThere will be no "overfitting" situationImplement Adaptive ForecastingSpecial data processing applicationsSmall sampleSoftware failure
The invention discloses a software failure time forecasting method based on a kernel partial least squares regression algorithm. Through the application of a kernel function technology, the problem of software reliability forecast is converted to the problem of recession estimation, and the kernel partial least squares regression algorithm is used for resolving the problem of the software reliability forecast. Through fully consideration of a small sample property of the software reliability forecast, the situations that the size of observational variables is bigger than that of observational samples and multicollinearity exists among the variables can be overcome by using the kernel function technology, and so that a model 'overfitting' situation arises in modeling approaches such as a neural network does not occur. By means of the software failure time forecasting method based on the kernel partial least squares regression algorithm, model parameters are automatically and continuously adjusted to fit the dynamic change in a failure process, therefore adaptive forecasting of the software reliability is achieved, and the adaptive capability of a software failure forecasting model is improved effectively.
Owner:HUZHOU TEACHERS COLLEGE

Principal component multiple regression analysis method for minimum oxygen concentration influence index in methane explosion

The invention discloses a principal component multiple regression analysis method for a minimum oxygen concentration influence index in methane explosion. The method includes the following steps: I, data collection and recording: carrying out explosion experiments on multi-component mixed flammable gases with different component concentrations and component proportions by using a visual sphericalclosed gas explosion experimental system, determining the minimum oxygen concentration of methane explosion after adding different volume fractions of multi-component mixed flammable gases in different proportions, and recording the minimum oxygen concentration in a data processor; and II, data analysis and processing: enabling the data processor to adopt a principal component analysis method, establishing a multiple regression model, performing factor analysis on experimental data recorded in the step I, finding out the main factors affecting the minimum oxygen concentration of methane explosion, and obtaining the influence index of each single gas in the multi-component mixed flammable gases on the minimum oxygen concentration of methane explosion at different concentrations. The schemeof the invention eliminates multi-collinearity and improves the accuracy and reliability of the regression model.
Owner:XIAN UNIV OF SCI & TECH

Research method based on GAMLSS model sediment transport contribution rate

The invention discloses a research method based on a GAMLSS model sediment transport contribution rate. The method comprises the steps of firstly collecting and arranging flow and sediment informationof a drainage basin outlet station; then computing a relation between each index and sediment transport and a fitting process line, computing 90% P-factor and R-factor, 50% quantile sequence varianceand a mean value, a correlation coefficient and an AIC; then using an attribution analysis method to analyze six indexes, thus acquiring an influence degree of each index on sediment transport variation; and at last, computing a contribution rate of each index to sediment transport. According to the research method based on the GAMLSS model sediment transport contribution rate provided by the invention, the problem that the prior art cannot accurately and comprehensively acquire the influence degree of the climate change and the human activities on the sediment transport contribution rate issolved, the principal component regression analysis is used, the influence of multicollinearity is eliminated, the influence generated by each variable mean is considered, and the influence of each variable interannual variance change on sediment transport is also considered.
Owner:XIAN UNIV OF TECH

Lightning fire daily occurrence probability predicting method based on space grids

The invention discloses a method for predicting daily occurrence probability of lightning fire. The method includes: building a data file, and taking each grid point and all fire points in a testing area as sampling points; performing multi-collinearity diagnose through data; selecting factors evidently influencing fire occurrence through Logistic Forward Wald analysis; building a daily occurrence probability model of the lightning fire through a Logistic model so as to analyze daily occurrence probability of the lightning fire, determining a lightning fire ignition threshold through a secondary judging theory, and calculating precision so as to perform precise analysis; on the basis of GIS, substituting day value data into the model for calculation so as to complete forecast of the daily occurrence probability of the lightning fire, and the like. The method has the advantages that the problem that the existing lightning fire predicting models rely on a lightning monitoring network is solved, wide application is achieved, the method can be used for calculating the daily occurrence probability of the lightning fire and analyzing future lightning fire occurrence trend, and the existing lightening fire pre-warning models are supplemented effectively.
Owner:INST OF FOREST ECOLOGY ENVIRONMENT & PROTECTION CHINESE ACAD OF FORESTRY

CPP-based hydrological model parameter dynamic calibration method

PendingCN110490228AImprove performanceSolve the problems caused by structural errorsForecastingCharacter and pattern recognitionContinuous flowModel parameters
The invention relates to a CPP-based hydrological model parameter dynamic calibration method. The method comprises the following steps: S1, periodically dividing the rate into a plurality of sub-periods on an annual scale, and calculating meteorological clustering indexes and underlying surface clustering indexes of all the sub-periods; screening out candidate clustering indexes based on a nonlinear relationship between the clustering indexes and the flow; S2, eliminating multiple colinearity among clustering indexes by adopting a PCA algorithm; S3, averaging the clustering index values of each sub-period of all years; performing clustering operation twice in sequence according to the meteorological indexes and the underlying surface indexes, and finally dividing the hydrological process in the year into four sub-periods for calibration; S4, independently optimizing TOPMODEL model parameters in each sub-period by adopting an improved parallel calibration scheme, and combining the TOPMODEL model parameters to generate continuous flow sequence values; and S5, evaluating the simulation performance of the hydrological model under different flow conditions by using a multi-index comprehensive evaluation system. According to the invention, the prediction capability of the hydrological model in a changing environment is effectively improved.
Owner:SUN YAT SEN UNIV
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products