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Information × Registration Number 0214U002332, 0111U001140 , R & D reports Title Identification of technical state (defect of continuity, loadings, boundary conditions) of observable thin-walled systems in extreme conditions popup.stage_title Head Obodan Nataly Illivna, Registration Date 29-01-2014 Organization Dniepropetrovsk national university popup.description2 The subject of investigation is process of identification of the technical state for thin-walled systems. The primary goal of the work is to create algorithm to identify model parameters for thin-walled systems under extreme operational conditions (external influences, damages) and to assess residual strength of the systems mentioned. Investigation methods belong to analytical and numerical methods. Main scientific results are, firstly, models of thin-walled systems under real-world operation conditions developed with employment of non-linear mathematical reality model being considered as inverse shell theory problems based on observations, secondly, development of adequate and state-of-the-art methods to solve the problems (the method is grounded upon numerical algorithm to solve the respective direct problem, regularized optimization criterion based on direct problem properties, and ability to decompose the problem that is to reveal dominant parameters of the inverse problems). Thirdly, the method to determine observation functions maximally influencing to the problem solution is proposed. Solutions for typical inverse problems (identification of an arbitrary nonaxisymmetrical load and damages like holes and cracks as well) are analyzed with employment of analytical ones wherever it is possible. For the case of external influence parameters identification, experimental results are obtained in order to verify the technique to ascertain the most representative parameters. The obtained solutions are shown to be applicable to residual operability prognosis. The obtained results (prognostic models and algorithms) may be used to assess load-bearing capacity of real-world thin-walled systems under operational conditions. Practical value of the research stems from theoretical foundations of residual strength estimation developed in the framework of the research. The theoretical foundations could be used to make decisions about subsequent operation of damaged systems. Obtained results could be employed to estimate operational readiness of aerostructures and anti-missile defense systems as well. A problem of residual operability is of great importance in the engineering industry and building industry. The damage estimation according to the abovementioned fracture criterion leads to resource-saving in these industries due to enlargement of the time periods between general overhauls. Proposed techniques could be used in space (Yuzhnoe Design Office), aviation (Progress Design Office Motor-Sich Ltd.), and engineering (Malyshev Plant Ltd.) industries. The damage identification technique and non-destructive evaluation techniques could be used in any monitoring system and for deterministic estimations of operability of engineering systems. Product Description popup.authors Адлуцький Віктор Якович Гавеля Галина Михайлівна Громов Василь Олександрович Гук Наталія Анатоліївна Пацюк Анатолій Григорович Полішко Олексій Миколайович Шаповал Ірина Павлівна Шерстюк Геннадій Григорович popup.nrat_date 2020-04-02 Close