In this article, we consider the features of the perception of student information in science, technology, engineering, and mathematics (STEM) education, in order to draw the attention of researchers to the topic of learning in practice through field training. The article shows the results of these studies in Russia and the Commonwealth of Independent States (CIS countries: Armenia, Azerbaijan, Belarus, Kazakhstan, Kyrgyzstan, Moldova, Russia, Tajikistan, and Uzbekistan, as an example) to reflect the global trends. For this purpose, we examined the expectations of students in Russia and the CIS countries from training related to lectures and field training. We created a questionnaire and distributed it in three Moscow-based universities (Moscow State University of Geodesy and Cartography—MIIGAiK, Moscow Aviation Institute—MAI, and Moscow City University—MCU). Our key assumption is that field practices in Russian universities are qualitatively different from the phenomenon described in European literature, where digital or remote field practices have already emerged. The results obtained through the survey show the tendency of students’ perceptions to fulfill practical duties (in a laboratory with instruments of field training) in STEM education.

The influence of reflective Bragg gratings that are formed in an active medium due to the spatial periodic modulation of gain on the spectral properties of lasing are investigated by an example of a pulsed Nd : YAG laser. It is shown that, at a certain choice of the formation regime of reflective gratings of gain, the lasing bandwidth can be reduced by a factor of 3 – 5, with a corresponding increase in the pulse energy and significant improvement of spatial beam quality.

Subject of study. A digital holographic system for layer-by-layer control of component quality in additive manufacturing able to determine the size and depth of defects on the surface of each layer was investigated. Method. The digital holographic system for layer-by-layer control of component quality in additive manufacturing operates based on a two-wavelength holographic interferometry method. The digital holographic system is based on a Michelson interferometer. The considered method involves recording holograms of the surface of each component layer at two adjacent wavelengths. As a result of hologram reconstruction, the complex amplitudes of the object wave in the reconstruction plane are determined, which, in turn, define the phases of the waves and their difference. The wave phase difference allows the depth of the defect on the component layer surface to be determined. A tunable diode laser and camera based on a CCD matrix are used as the radiation source and detector, respectively. Main results. The results of the investigation of the surfaces of additively manufactured components using the two-wavelength holographic interferometry method are presented. The recognition of large irregularities is possible through expansion of the phase pattern. The detection of surface defects with the size of 25 µm is demonstrated. The reconstructed surface of a component manufactured by laser sintering of successive layers using the M250 additive setup for selective laser sintering and the reconstructed surface of a millimeter-scale macroscopic object are presented. Practical significance. The possible use of the digital holographic system for component quality control in industrial settings, including those applying additive technologies, is demonstrated. The component quality criterion is the absence of defects (cavities or protrusions) with size larger than 25 µm.

В работе предложен метод поиска и оценки выбора материалов для микро-опто-электромеханических переключателей (МОЭМС), применяемых в системах связи нового поколения. В качестве критерия выбора материала приняты диэлектрическая проницаемость, показатель преломления и ширина запрещенной зоны. Проведено исследование влияния данных параметров на эффективность оптических компонентов систем связи. Использованы методы машинного обучения для предсказания свой­ств материалов и выявлены перспективные материалы с высокой диэлектрической проницаемостью. Полученные результаты будут полезны при разработке новых методов проектирования оптических и радиочастотных компонентов связи.