2 results about "Diffusion weighting" patented technology

The application discloses a flow field gradient determination method and device based on iterative diffusion, equipment, medium and product, and belongs to the technical field of numerical simulation. The method comprises the following steps: dividing a flow field region into a shock region and a smooth region; selecting prior units from the shock region and the smooth region respectively, and calculating gradient values of the prior units; marking the gradient values of the prior units as a frozen state as reference values for neighborhood diffusion, so as to iteratively update gradient values of non-prior units; in the diffusion process, based on the geometric relationship between the non-prior unit and each adjacent unit, the anisotropic diffusion weight between the non-prior unit and each adjacent unit is calculated; the gradient value of the non-prior unit is iteratively updated by using the diffusion weight and the gradient value of each adjacent unit until a convergence condition is reached; and the gradient value of each unit after convergence is determined as the flow field gradient. The application can improve the accuracy and stability of gradient calculation.

This invention relates to a method and system for denoising phase-shifted shear speckle interferograms, specifically within the field of phase-shifted shear speckle interferogram denoising technology. The method includes: acquiring several phase-shifted shear speckle interferograms; calculating discrete complex phase quantities based on the several phase-shifted shear speckle interferograms, and calculating discrete wrapped phases based on the discrete complex phase quantities; calculating phase confidence weights based on the discrete complex phase quantities and discrete wrapped phases; constructing diffusion weight coefficients based on the phase confidence weights; calculating discrete phase gradients based on the discrete wrapped phases using a finite difference method, and performing weighted diffusion processing on the discrete phase gradients based on the diffusion weight coefficients; and reconstructing the phase of the phase-shifted shear speckle interferograms based on the weighted diffusion processed discrete phase gradients to obtain the denoised phase distribution. This invention can effectively denoise phase-shifted shear speckle interferograms.