Розглянуто схему заміщення побутового холодильника у вигляді еквівалентного активного чотириполюсника, вхідними затискачами якого прийнято випарник, а вихідними - конденсатор.  Математичну модель холодильника як чотириполюсника розроблено у вигляді системи двох рівнянь теплового балансу відносно температурного напору і теплового потоку, який трансформується упродовж роботи холодильної машини. Надано визначення режимів неробочого ходу і короткого замикання холодильної машини. Розроблену модель холодильника як чотириполюсника призначено для  використання у системах SMART  refrigeration.

Introduction. Nowadays the system of future engineers training is entering the new stage of its development and new horizons are opening-connected with formation of teaching pluralism, developing of new teaching ways and methods, which lead to the appearance of new approaches to training process due to the necessity of novel technologies implementation that should support students motivation for lifelong learning and stimulate their creativity. E-learning, mlearning, interactive e-books, virtual learning realities-such neologisms integrate to all spheres of education constantly, and engineering training is not an exception. Purpose. The aim of the paper is to specify the main methodological and psychological principles of virtual educational environment creation and implementation. Results. Essential features of the "virtual learning environment" concept are described and fundamental properties of virtual learning environment which is used in the educational process are given. Originality. The major pro and contra arguments of these novelties utilization for the educational purposes in the process of training are observed in the paper on the example of virtual gamificated learning environment creation. Conclusion. Pedagogic system which corresponds to the virtual learning in the artificial environment, should be considered as situational, because the features of its application are determined each time by the specific conditions of training and that virtual educational situation that exists only in this area, at this time, between specific subjects and objects of education. The necessity of the special didactics development for virtual learning environments is obvious. It is necessary to create and implement virtual learning environments for every

The paper relates to the field of measuring technologies and deals with the enhancement of thermoconvective method when it is applied for the experimental determination of such hydrodynamics indicators as mass flow rate and velocity of flow by their indirect parameters - capacity of the heater and the temperatures obtained from two thermal sensors, provided that they are located on the hermetic piping system surface. The issue of determination of correction factor on heterogeneity of liquid temperature distribution in the pipe cross section depending on pipe diameter and fluid movement velocity was clarified. According to the results of numerical calculations, the dependencies of temperature gradient on the pipe surface and the correction factor on the heterogeneity of the temperature distribution along the pipe cross-section under the heater in the function of the velocity of flow in pipes of different diameters are plotted. These dependencies specify the thermal method of studying the fluid flow in the pipes, simplify the experiment conduction, are useful in processing of the obtained results and can be applied in measuring engineering.

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