The theoretical substantiation for choosing a rational geometry parameter of “irradiator – object” system is presented. Selecting it is crucial for designing infrared drying machines for solid bodies, in the form of two concentric infinitely long bodies, when one body covers the other. Also, the effectiveness validation of this system is presented in practice using a laboratory stand in the form of two cylinders. An infrared flexible membranous electric heater is sprayed and fixed on the walls of cylinders, an optical sensor was installed between them in order to determine the reflection of the radiation flux. Positive results make it possible to obtain recommendations for designing infrared installations to dry solid bodies.

The most common and important method of agricultural products processing is drying. The quality of finished product, energy intensity and material intensity of the entire processing depend on the drying process. Drying the seeds of different crops is influenced by many factors: the structure, size, properties and condition. We studied the process of drying oil-bearing small-seeded crops taking rapeseeds as samples. Rapeseed is covered with a hard shell that prevents the release of moisture; in this case the seeds should be dried at low temperatures. High temperature causes rapeseeds to have low quality indicators. Analysis of the existing equipment has shown that nowadays there are no special systems for drying small-seeded crops, and the drying process is carried out on grain dryers which are characterized by large seeds losses, considerable energy costs and high temperatures. The main advantages of the developed infrared dryer of conveyor cascade type are the lack of hot zones, the uniform heating and the minimum percentage of seeds losses because of their blowing out and removal. In addition, the heat carriers used in the dryer of conveyor cascade type help to perform the drying process at the required wavelength, that can affect only the moisture in the seeds.

A source of inaccuracy in regression models is supposed to be the statistical nature of a model and metrology inaccuracy related to the measuring explanatory and response variables. A number of approaches to the assessing inaccuracy of regression models are available. However, their use in searching for a solution to engineering problems concerning the assessing multiple regression inaccuracy is restricted by insufficiently developed mathematical tools. When explanatory variables assigned appropriately the inaccuracy of a regression depends on the reproducibility of test results. The reported simulation study investigates the importance of a measurement error to the variance of a normally distributed random variable for small sample sizes between 2 and 30 and coefficients of variation 1, 2, 10, 20, 40, 60. The effect of inaccuracy is analyzed relying on a relative confidence interval of variances estimated as a difference between variance intervals for a variable measured inaccurately and accurately divided by a confidence interval of the variance for an accurately measured variable. The outcomes to emerge from the study are quantity-related estimates for the effect of metrology inaccuracy in the measuring random variables with various coefficients of variation for small sample sizes and different relative measurement errors. For the assessing we use 106 retests and a maximal variance for the same number of repeated tests. The results make possible to evaluate an effect of metrology inaccuracy for diverse coefficients of test results variation, as well as determine an appropriate extent of testing for assigned model inaccuracies and a known measurement error. In addition, practical application of obtained results is shown.

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In agriculture, single-transformer consumer substations are widely used. Failure of a transformer in such a substation adversely affects the reliability of power supply to agricultural consumers. The most common reason for the failure of consumer transformers (over 50%) is turn-to-turn short circuits in their windings. Therefore, timely diagnostics of turn-to-turn faults in the windings of such transformers is an urgent task. In this case, it is necessary to take into account the specific conditions of rural electrical networks. It is recognized as permissible to carry out diagnostics at idle running of the transformer. Designed with assumptions in mind, the diagnostic device is simple and easy to use. The operation of the device was investigated on an electronic model using the Matlab software package integrated with the design and programming environment based on Simulink models. As a result of research, it was found that the device is efficient and efficient.