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Information × Registration Number 0225U002091, (0123U101691) , R & D reports Title Mathematical and computer modeling of mass transfer processes in stochastically heterogeneous layered structures applicable in military facilities popup.stage_title Комп’ютерне моделювання процесів перенесення у випадково неоднорідному шарі за експериментальних даних на границі тіла. Head Pukach Petro Ya., Доктор технічних наук Registration Date 18-02-2025 Organization Lviv Polytechnic National University popup.description1 Construction of mathematical models of transfer processes in randomly inhomogeneous layered bodies for arbitrary sizes of layers, two-point correlation function of the field based on experimental data at the boundary of the body, development of a software complex popup.description2 According to the experimental data, a linear regression was constructed by the method of least squares, which is considered as the boundary conditions of the proposed mathematical model of transfer processes in the layer, which are described by differential levels in the parts of the second-order derivatives, when the value of the function was set to be searched for at the upper boundary of the layer, and only the lower boundary is known . experimental data on the desired function at certain points in time. The two-sided statistical estimation of the solution to the initial-boundary value problem is determined in terms of the coefficients of linear regression, which is analyzed in relation to the influence of the sample size and covariance. Confidence intervals for the coefficients of the regression equation with a given level of reliability are established. The corresponding confidence intervals for the desired function are determined based on the obtained solution of the initial-boundary value problem, and their limits are determined by the confidence intervals for the linear regression coefficients.The formula for determining the two-tailed critical region based on Fisher's test was obtained and analyzed. Numerical analysis of the solution to the initial-boundary value problem is carried out depending on the statistical characteristics of the sample. Calculation formulas for ensemble-averaged phase configurations of concentration fields are obtained taking into account the regression model at the lower boundary of the body. Reliable intervals for solutions of the boundary value problem of diffusion in the layer are established under the linear regression model as a boundary condition on a part of the outer surface of the body. Based on the results of the computer experiment, the behavior of the concentration function in a multilayer body was analyzed with the available experimental data at the body boundary for different types of samples. Product Description popup.authors Bilushchak Halyna I. Bilushchak Yurii I. Vovk Myroslava I. Demkiv Ihor I. Kunynets Andrii V. Lytvyn Vasyl V. Chernukha Olha Yu. Chernukha Yurii A. popup.nrat_date 2025-02-18 Close