3 results about "Mathematical relation" patented technology

The present application relates to a kind of improved radiation transmission model mangrove chlorophyll estimation method, comprising: the measured data of the tree height, crown width and leaf area index of mangrove are collected;Mathematical relationship between leaf area index and tree height, crown width is constructed;Simulated spectral data is generated as training set using improved radiation transmission model;The sensitive feature screening of mangrove functional traits is carried out;Random forest inversion model based on physical constraint is constructed;The present application estimates the chlorophyll content of mangrove using the random forest inversion model based on physical constraint.The beneficial effects of the present application are: the present application can effectively improve the precision of chlorophyll inversion, provide scientific basis for the fine inversion of mangrove chlorophyll, provide data support and decision-making reference for the protection and scientific management of mangrove.

This invention presents a method for establishing large deformation viscoelastic constitutive relations based on Prony technology. It addresses the problems of existing viscoelastic constitutive models lacking universality, and the complexity and programming difficulties associated with their mathematical relationships. The invention includes: decomposing the stress tensor into the sum of the deviatoric stress tensor and the mean stress; decomposing the strain tensor into the sum of the deviatoric strain tensor and the mean strain; and providing a convolutional expression for the deviatoric stress tensor and the mean stress. The increment of the deviatoric stress tensor is expressed as a function of the deviatoric strain increment, and the increment of the mean stress is expressed as a function of the mean strain increment. The tensor form of the incremental constitutive relation is written in matrix form. This method has been programmed, and the numerical results obtained from the program agree well with the experimental results in specimen-level experiments on solid rocket motor propellant grains.

The present application belongs to the field of geophysical exploration, and particularly relates to a method for calculating acoustic curve by using elastic parameters of drilling core to constrain, which comprises the following steps: step 1, obtaining logging resistivity curve of drilling in a study area; step 2, obtaining core samples of different lithology at each depth of the drilling; step 3, measuring elastic parameters of the core samples, including acoustic velocity and resistivity; step 4, establishing mathematical relationship of resistivity and acoustic velocity parameters of different strata and different lithology; step 5, establishing geological model of the drilling according to logging results of the drilling; and step 6, calculating acoustic velocity curve of the drilling based on the geological model of the drilling and the fitted mathematical relationship. The method can obtain accurate stratum acoustic curve by calculating pseudo-acoustic curve through the constraint of elastic parameters of drilling core.