The article considers the solution of the urgent problem of calculating the size of the effective focal spot of a microfocus X-ray tube using computer modeling methods. The principle of operation of the calculation method used by the authors is to compare interference images obtained using tested microfocus X-ray tubes with simulated interference patterns formed using the developed software by numerically solving the wave equation. It should be noted that modeling a one-dimensional interference pattern using fast Fourier transform requires a significant amount of RAM and takes considerable time even when using modern computer equipment. The paper presents the results of modeling phase contrast profiles for two types of test objects – nylon fishing line and aluminum wire. The considered method for determining the size of the focal spot is characterized by good sensitivity and allows efficient and high-precision calculations for all types of microfocus X-ray tubes.

Keywords: computer modeling, X-ray tube, microfocus source, focal spot, non-destructive testing

The paper deals with the issues of modeling the processes of laser radiation absorption in contact with a biological object, which leads to a significant increase in temperature in the interaction zone. For organic tissues, when the temperature rises above a certain value, their damage begins, and then the processes of destruction are observed. With an increase in the speed of movement of the laser beam on the surface, the width of the incision and the level of injury decrease, as the time of interaction of the radiation with the tissue decreases. In this paper, we consider various models for performing calculations: using complex ratios taking into account the thickness or using expressions for an object of semi-infinite thickness. The regularities of the growth of the average temperature and the process of establishing the thermal balance on the surface of the body, depending on the parameters of the laser radiation pulses, are also investigated.

Keywords: computer simulation, medical laser, laser incision, biological tissues, temperature field, level of injury, pulse packet, speed of movement

The article deals with the power supply of the microcontroller core, which allows you to adjust the voltage to ensure the necessary balance between performance and power consumption of the system. When using this source, the core power supply voltage depends on the fill factor of the pulse-width modulated generator. These expressions allow you to adapt the proposed source for a microcontroller with an arbitrary power supply voltage.

Keywords: microcontroller, microprocessor system, embedded system, stabilizer, core power, performance, power consumption, video surveillance system, pulse-width modulation, fill factor