The purpose of this study is to create a methodology for assessing the risks arising from climatic tests of radio-electronic equipment. The article considers the effect of additional misalignment of transmission lines arising under conditions of temperature inhomogeneities on the increase in consumer and producer risks. A method of selecting a protective measuring band is proposed to minimize the probability of false acceptance and rejection of the tested devices. The results obtained make it possible to determine the optimal, from the point of view of the risks of the consumer and the manufacturer, the coefficient of the protective band of radio engineering measurement.

The possibility of application of the interval analysis for data processing in the field of spectral analysis is considered. It is assumed that the data have interval uncertainty; therefore the problem of finding unknown concentrations is posed as a linear interval tolerance problem. The incompatibility of the interval system of linear algebraic equations is shown for the initial data using the apparatus of the recognizing functional. The relevance of the topic is due to the need for regularization of inconsistent interval systems of linear equations. The idea of S. P. Shary of a combined method for correcting a linear tolerance problem has been implemented. A new method for managing the solution by changing the linear algebraic equations interval system matrix elements radii has been developed. The research results can be used for example, to calculate the substance’s concentrations by measurement of the characteristic X-ray radiation.

The article describes a new method for enthalpy calibration of differential scanning calorimeters. The method allows you to remove the limitation on the temperature range in which this metrological procedure can be carried out. The proposed method does not require the use of standard samples of heats of fusion, therefore, it is not limited by the thermophysical properties of the certified substances. The developed method solves the problem of increasing the accuracy of measurements of specific enthalpy and heats of phase transitions of various substances for all types of differential scanning calorimeters. The effectiveness of the method in solving this problem is confirmed and illustrated by the authors by comparing the results of measuring the heats of fusion of a number of metals. The results obtained on differential scanning calorimeters calibrated by the new method and on the same instruments, but calibrated in accordance with the generally accepted standardized method of the International Union of Theoretical and Applied Chemistry, were compared. The authors experimentally revealed the advantages of the new method in terms of saving time and money required for calibration. The article will be of interest to those specialists who use differential scanning calorimeters in the development of new materials, control of technological processes, production, input and output control, as well as to those specialists who develop methods for research and measurement of various materials on differential scanning calorimeters.

The applied application of the Lyapunov characteristic function is determined by the properties of its estimates. Probabilistic characteristics of estimates of the Lyapunov characteristic function are described for the first time. The probabilistic characteristics of random values of estimates of the Lyapunov function are empirically estimated using statistical methods. The Matlab package has developed a model of a special device for obtaining estimates of the characteristic function by a direct method. A quasi-deterministic signal is fed to the input of the model, the instantaneous values of which are distributed according to the arcsine law, and an array of values of estimates of the Lyapunov function is obtained at the output, which is used to estimate the probabilistic characteristics of these estimates. Statistical estimation was performed by an indirect method. It is established that the values of the estimates of the Lyapunov characteristic function are distributed according to the normal law. The results of the research will be useful in engineering calculations, for example, when detecting message transmission errors in modems with a modulated characteristic function.