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The aim of the study was to determine the state of psychophysiological functions of skilled athletes specializing in academic rowing, in relation to the level of existing stress, emotional stability and the effectiveness of mental self-regulation and adaptability. To determine the state of psychophysiological functions, the maximum rate of movement of the hand (according to the method of tapping test) used diagnostic complex "Diagnostics-1" (MV Makarenko, VS Lyzogub). To study the strategies of coping with stress (coping strategies) and to determine the priority style of coping with stressful situations in athletes, the questionnaire "Identification of individual coping strategies" by E. Heim was used. To assess the current mental state of athletes (namely – the level of existing stress), emotional stability and effectiveness of mental self-regulation and adaptability, the test of color choice M. Luscher was used. In the studied group of athletes revealed the prevalence of respondents with a high level of stress resistance, high and medium level of emotional stability, average efficiency of mental self-regulation and adaptability. The most common coping strategies among the surveyed athletes were: in the cognitive sphere – "preservation of self-control", in the emotional – "optimism", in the behavioral – "distraction". In general, the use of adaptive stress management strategies outnumbered non-adaptive and relatively adaptive strategies among athletes. Specific psychophysiological markers of stress resistance, efficiency of mental self-regulation and adaptability of the examined athletes were indicators of strength and efficiency of sensorimotor activity. Emotional stability of the surveyed athletes was associated with the strength and functional mobility of nervous processes. The identified relationships between indicators of psychophysiological functions and psychological characteristics of athletes can have prognostic value and be used to optimize sports improvement in this sport.

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Increasing reliability of bolted electrical contact connections is an important problem in power engineering. Such connections are very common and their damage can lead to serious consequences. One of the ways to increase reliability of bolted electrical connections is the use of special devices based on shape memory alloys (SMAs). This article contains an analysis of four devices that destroy films (oxides, sulfides etc.) which form on a contact surface of bolted electrical connections during operation. Destruction of such films slows down process of a contact connection degradation and, ac cordingly, extends its service life, thereby increasing reliability of a contact connection. The following devices were analyzed: a conical washer made of SMA, "Detachable connection of conductors with a contact crown nut", "Terminal lug" with shape memory effect (SME) element. These devices have SME elements which during activation increase a contact pressure in an electrical connection and, accordingly, destroy films on a contact surface. Another "Terminal lug" with SME element was also analyzed. This device has SME element which during activation displaces one contact rela tive to another. This motion cleans a contact surface from films without affecting a contact pressure. Analysis of these devices, in particular using the finite element method, which was implemented using Ansys 2020 R2 Academic software, showed the following disadvantages and features of the above-mentioned devices: the need to manufacture specially designed contact connection elements, the locality of a pressure increase on a contact surface, and the need to disassemble contact connections when installing SME elements. Based on the conducted analysis, a new design of a contact connection was proposed. This new design does not have indicated disadvantages and its principle of operation is based on a combined destruction of films on a contact surface by increasing a contact pressure and by the relative displacement of the contacts.

As a result of the research, the deformation properties of aluminosilicate adhesives modified with nitrate salts and intended for gluing wooden products and structures made of pine, beech and oak wood at different stages of their hardening were determined. Considering that pine is the most common wood in the manufacture of products and structures, then in order to reduce the numerical values of the elastic modulus in glued materials, it is advisable to add ammonium, lithium and sodium nitrates in an amount of 0.5%, potassium nitrate in an amount of 1% into the composition of an aluminosilicate adhesive. which will ensure the approximation of the elastic modulus values to the values of the unmodified aluminosilicate adhesive and will significantly affect the water resistance of the glue joint and the depth of penetration of the adhesive into the wood structure. For gluing beech wood products to reduce the elasticity modulus, it is advisable to introduce 0.5% ammonium and potassium nitrates and 1% lithium and sodium nitrates, which will reduce the numerical values of the elastic modulus in glued materials by 1.18 and 1.53 times compared with the values of the elastic modulus of the unmodified aluminosilicate adhesive. For gluing oak wood products to reduce the elasticity modulus, it is advisable to introduce 0.5% potassium nitrate and 1.5% sodium nitrate, which will reduce the numerical values of the elastic modulus in glued materials by 1.4 and 2.83 times compared to the values modulus of elasticity of unmodified aluminosilicate adhesive.