In this thesis the problems of identification accuracy of elastic properties of materials are examined. The main object of study is samples of various materials and their elastic properties. This is an important subject of theoretical studies of various materials. The main thesis objective is to create an effective technology for precise identification of all the elastic characteristics of the sample. The de-veloped algorithms are to be applied in the material manufacturing industry. Thesis also aims at exploring accuracy and sensitivity of the identification of elastic properties of materials.
The paper deals with a number of objectives: 1) to optimize the geometric parameters of the sample striving for more accurate identification results of elas-tic properties; 2) to identify mode shapes of sample and regulate their place in spectrum of eigenvalues in order to minimize the distortion of the objective function; 3) to create the implementation algorithms of proposed technologies and verify their capabilities experimentally. The first task is formulated taking into account the relatively high level of identification error of elastic properties of composite materials. The second objective relates to distortion of the objec-tive function in the process of updating the mathematical model with the pre-sumed elastic characteristics of material.
The thesis is composed of four chapters, the summary of results, the list of literature and the list of author’s publications on the topic of dissertation.
In the introductory chapter the relevance of the problem as well as its scien-tific novelty and practical significance are presented and the research object, goals and objectives are described. The chapter also sets the research methodol-ogy and defended prepositions, presents reports and publications on the topic dissertation and the structure of the thesis.
The first chapter is for the review of the literature. It includes review and analysis of the literature on the identification of material elastic properties, the algorithms of global optimization and the genetic algorithms in the relevance area of identification of elastic properties. At the end of the chapter the conclu-sions fleshing out objectives are formulated.
The second chapter provides description of identification technology of elastic properties, and mathematical models of materials used in tests.
The third chapter provides the improvements of technology and describes tests, which demonstrate the effectiveness of the proposals.
The fourth chapter presents an application of the developed technology and concept of user interface.
Five reports on the topic of dissertation were presented in scientific confer-ences in Lithuania and abroad, and four articles were published: in scientific journal included in ISI Web of Science list; in scientific journal, indexed in other databases; in international conference material; in local conference material.
Raktažodžiai: elastic properties, composites, identification, genetic algorithms, optimization