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The modal analysis is considered as one of the lines of technical diagnostics for evaluating the quality of polymer composite materials (PCMs). It allows one to link the structure of modal characteristics of PCM element base in the amplitude-frequency domain. In the course of modal analysis, the complex construction of PCM as a heterogeneous material is transformed into a set of easy-to-understand independent systems with one degree of freedom. This structural approach is used to analyze the structure of PCM components. A laser is used to form an external action, with the help of which PCM components can form a wave field when vibrations pass through its thickness. Vibrations and deformations of PCM structural elements under a mechanical excitation are considered as the intrinsic vibration forms (vibration modes) of PCM elements -the filler and matrices. High-frequency laser actions extracts a constant wavefront, which is used for constructing an algorithm for recognition of the structure of PCM, including the detection of possible defects, such as changes in its density and various stratifications. To assess the technical condition of structural elements of PCM, a mathematical model was developed to assess the effect of defects on passage of a wave and the excitation of modal vibrations by the element base of PCM. The mathematical algorithm for estimating the acoustic conductivity of the wavefront, together with experimental data, was used for constructing a wave diagnostics algorithm. It made it possible to create an algorithm for a technical diagnostics of PCM elements. An experiment was conducted on the laser action on a carbon fiber panel with specially created defects. The frequency values found in various zones of carbon fiber showed a qualitative and quantitative change in the structure of PCM. It is shown that, to construct an effective model for diagnosing the technical condition of PCM elements, more experimental studies are required.

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An algorithm for constructing a dynamic analysis during the formation of a wave field of stand for testing turbines and the effect of the frequency interaction of the stand’s elements on the measurement of its magnitude is described. The research algorithm involves the use of theoretical solutions of nonlinear wave processes using linear oscillations, refined by experiments. The diagnostic model can determine the technical condition of the stand’s elements and also determine the causes of the discrepancies between the calculated and measured turbine power values. To clarify the stiffness coefficients between the stand’s elements, a modal analysis was used to obtain the range of their changes depending on the external dynamic load, which made it possible to assess the impact of changes in the frequency interaction conditions on the turbine power measurement at different test modes. The conditions for amplifying the amplitude of oscillations at their eigenfrequencies are obtained, and the value of the possible deviation of the expected power value at its measurement for specific modes of the turbine is calculated. The algorithm allows to estimate the dynamic state of the stand-in different research modes of turbines and give recommendations for reducing the level of frequency interaction.

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One of the main directions of changeover from the inertial scenario to innovative scenario of increasing of the energy efficiency by system management of energy resources is considered. Semantic aspects, concepts and conceptual models of system of management of energy resources are defined. A method for assessment of energy management using a multiplicative model the impact of technological and managerial factors with the use of pattern recognition theory is developed. Guidelines and engineering facilities to increasing of the energy efficiency in the framework of the system of management of energy resources on the basis of the results obtained are given. Keywords-energy efficiency scenarios, energy consumption process, system management of energy resources, conceptual design, engineering of increasing energy efficiency

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