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Information × Registration Number 0221U105001, 0116U005141 , R & D reports Title Basic researches of physicomechanical properties of ground structures by geoacoustic methods popup.stage_title Head Shchyptsov Oleksandr A., Доктор географічних наук Registration Date 07-05-2021 Organization State Institution "Scientific Hydrophysical Center of the National Academy of Sciences of Ukraine" popup.description2  The object of study - the terrain, bottom sediments of the oceans and the signals reflected and scattered from them. The purpose of the work is to use remote-acoustic methods to determine the composition of bottom sediments and their theoretical substantiation. Research method - formulation and solution of problems on modeling the determination of physical and mechanical properties of bottom sediments on the reflected and scattered acoustic field. A mathematical model is considered, which determines the oblique incidence of an acoustic wave on the boundary, as well as a layer of gas-droplet mixture or bubble liquid of finite thickness. The range of change of volume compositions of drops in which zero value of coefficient of reflection at low frequencies at an inclined fall of a wave is possible is established. For the first time, an original model of static scattering by the bottom surface of an acoustic field is presented. Calculations of model curves for bistatic scattering force for 100 kHz for sandy and silty bottom are performed. The remote-acoustic method of layer-by-layer reconstruction of geoacoustic parameters of bottom layers with the use of parametric models of signal formation reflected from the layered half-space during coherent sounding of the sea shelf is proposed and theoretically substantiated. A crucial rule based on the consistent application of the MUSIC projection algorithm is used. The efficiency and stability of search and acceptance algorithms for solutions with limited a priori data have been studied. The remote-acoustic method, the method of classification of bottom soil types according to the reflected signals of a single-beam echo sounder, is proposed. Two models of classification on the basis of models are theoretically substantiated. Numerical calculations are performed and a model of the time dependence of the acoustic intensity of the reflected signal on the bottom is described. Product Description popup.authors Vlasova Iryna M Moroz Mykola S Nevierova Svitlana I Nesterenko Lubov V Peshkov Oleksii V Fedoseenkov Sergii H Shundel Oleksii I Shchyptsov Oleksandr A popup.nrat_date 2021-05-07 Close