The results of experimental and theoretical investigation of dynamic and static characteristics of a thermal object (electric oven) as a controlled plant are presented in the paper. The up-to-date microprocessor instruments were applied during the investigation. The experimental study of the plant was made by obtaining the step response curves for the controlling action channel and for the disturbance channel. Fifteen step response curves were recorded during the study. These curves were applied for development of the mathematical model of the plant in the form of static characteristics equations, transfer functions and differential equations. The structure of the model was chosen. The numerical values of the model parameters were calculated. The adequacy of the model was verified. The relative errors of the calculated values of the static characteristics points do not exceed 5 %. The maximum reduced error of the simulated step response curve in comparison to the experimental curve is 7% for the proposed combined method of defining the time constants. The developed model was implemented in a programmable logic controller in order to provide the possibility of studying the automatic control loop with various control laws.

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The results of the pulse-width modulation algorithms analysis are presented in the paper. The following two algorithms are analyzed: pulse-width modulator (PWM) based on the sawtooth waveform generator and PWM based on an integrator and a switch element. Mathematical formulae for designing the tuning parameters of PWM algorithms are presented. An improved PWM algorithm is suggested for a programmable logic controller (PLC) operating with integer variables without a filter of the input signal. The improved algorithm provides elimination of the influence of the input signal's noise on the PLC output signal. PLC output relay contact bouncing is eliminated by means of the improved algorithm. The reliability of PLC is improved and the operation time of PLC output relay contact is prolonged thanks to the improved PWM algorithm. The example of PWM application in an automatic controller for controlling a thermal plant is presented. The advantages of the improved PWM algorithm application are demonstrated. The technique for PWM pulses period defining with taking into account the dynamical properties of the controlled plant is presented.

The purpose of the article is to present the research results on the landscape changes dynamics in the frame of the Educational and Professional Program “Ecology and Environmental Protection” developed at the Department of Environmental Sciences at National Aviation University. The noosphere paradigm as the most integral bio-adequate basis of the interaction between the society and ambient environment under conditions of present-day challenges is highlighted. The advantages of education in English are emphasized in terms of the abundance of primary educational sources to tackle environmental challenges especially connected with the warfare activities in the country. Digital technologies and remote sensing development within the framework of the educational and professional program provide students, in particular, with the opportunity to perform landscape changes assessment due to long-term anthropogenic stress. The example of the border region landscapes of the Novgorod-Siverskyi Polissia is considered.

The technique for designing the optimal value of the filter time constant for analog signal is presented in the paper. This technique is based on the objective function which takes into account the quality index of the filtration process and the dynamic error of the filtered signal. The experimental study of the transient processes in a thermal plant was carried out in order to analyze the influence of the filter parameters on the quality of the filtration process. The optimal value of the filter time constant was designed on the basis of the developed technique for the obtained experimental data. The experimental transient process was compared to the filtered one which was obtained with application of a filter with an optimal time constant. Application of the developed technique for designing the optimal time constant in the automated measurement and control systems will ensure high quality of the filtration process and small dynamic error of the filtered signal.