536 research outputs found

    The use of a multicopter in mine surveying

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    Facebook Tools and Digital Learning Achievements in Higher Education

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    During recent years there has been a significant increase in the usage of technological tools in general, and in academic teaching in particular. Many programs have been developed, including online teaching and online courses at educational institutions. In this paper, we discuss the Facebook social network and its use at the University. The research shows that Facebook groups are used to facilitate communication between students, to foster a positive social climate, to create dialogue and to share learning material among group members. The paper examines students’ achievements and their satisfaction with the impact of the Facebook group on the academic course, in order to examine whether the use of Facebook groups in academic courses can improve course quality and students’ achievements

    The main structural element of a reinforced concrete supports: mathematical modeling of mechanical vibrations

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    The problem of mathematical modeling of a reinforced concrete supports mechanical vibrations is considered. The basic vibrations of the main structural element (a road) are taken into account. The eigenfrequencies of the first three vibration modes of the rod are determined without and with prestressing of the rod. Participation factor of the basic, second and third modes is investigated

    The role played by evanescent fields in the process of formation of radiation of combined radiating systems

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    The problem of active controlling of the structure of fields of combined radiating systems within their near zone is studied. The characteristic size of this zone is on the order of the wavelength and is characterized by the presence of evanescent (nonpropagating) fields, which are formed, among other things, due to the interference interaction of radiators of the system. Using multipole expansions for fields and special summation formulas for such expansions allows one to obtain concise expressions convenient in carrying out numerical calculations. The results of calculations confirm that the evanescent fields’ structure plays a significant part in the process of the formation of the radiation field

    Numerical modeling and experimental investigation of the breadboard model of a near-field interference microscope

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    A circuit design for technology of near-field interference microwave microscopy using evanescent fields of several active radiators (probes) is suggested and substantiated. The feasibility of providing the spatial overlap of the evanescent fields of two probes representing expanding coaxial conical horns is demonstrated. It is shown that the structure of the electromagnetic field in the region of overlap can effectively be controlled by changing the phase difference of oscillations arriving at inputs of the probes. This technology can be used for diagnostics of liquid media comprising dielectric inhomogeneities, flaw detection, and hygroscopy

    Control of the magnitude and spatial distribution of interference energy flows in near fields of systems of identical radiators

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    The problem of active control for both the magnitude and spatial distribution of individual components of the interference component of the Poynting vector within the near zone of a system of radiators is studied. The characteristic size of this zone is on the order of the wavelength and is characterized by the presence of evanescent (nonpropagating) fields, which are formed due to the interference interaction of radiators. Using multipole expansions for fields and special summation formulas for such expansions allows one to obtain concise expressions convenient in carrying out numerical calculations. The results of calculations confirm the feasibility of the above-mentioned control in principle in solving problems of medium and object sensing

    Foraging in Boreal Forest: Wild Food Plants of the Republic of Karelia, NW Russia

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    While the current consumption of wild food plants in the taiga of the American continent is a relatively well-researched phenomenon, the European taiga area is heavily underrepresented in the scientific literature. The region is important due to its distinctive ecological conditions with restricted seasonal availability of wild plants. During an ethnobotanical field study conducted in 2018-2019, 73 people from ten settlements in the Republic of Karelia were interviewed. In addition, we conducted historical data analysis and ethnographical source analysis. The most widely consumed wild food plants are forest berries (three Vaccinium species, and Rubus chamaemorus), sap-yielding Betula and acidic Rumex. While throughout the lifetime of the interviewees the list of used plants did not change considerably, the ways in which they are processed and stored underwent several stages in function of centrally available goods, people's welfare, technical progress, and ideas about the harm and benefit of various products and technological processes. Differences in the food use of wild plants among different ethnic groups living in the region were on the individual level, while all groups exhibited high variability in the methods of preparation of most used berries. The sustainability of berry use over time has both ecological and economical factors.While the current consumption of wild food plants in the taiga of the American continent is a relatively well-researched phenomenon, the European taiga area is heavily underrepresented in the scientific literature. The region is important due to its distinctive ecological conditions with restricted seasonal availability of wild plants. During an ethnobotanical field study conducted in 2018-2019, 73 people from ten settlements in the Republic of Karelia were interviewed. In addition, we conducted historical data analysis and ethnographical source analysis. The most widely consumed wild food plants are forest berries (three Vaccinium species, and Rubus chamaemorus), sapyielding Betula and acidic Rumex. While throughout the lifetime of the interviewees the list of used plants did not change considerably, the ways in which they are processed and stored underwent several stages in function of centrally available goods, people s welfare, technical progress, and ideas about the harm and benefit of various products and technological processes. Differences in the food use of wild plants among different ethnic groups living in the region were on the individual level, while all groups exhibited high variability in the methods of preparation of most used berries. The sustainability of berry use over time has both ecological and economical factors

    Multiple domains in Siz SUMO ligases contribute to substrate selectivity.

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    Saccharomyces cerevisiae contains two Siz/PIAS SUMO E3 ligases, Siz1 and Siz2/Nfi1, and one other known ligase, Mms21. Although ubiquitin ligases are highly substrate-specific, the degree to which SUMO ligases target distinct sets of substrates is unknown. Here we show that although Siz1 and Siz2 each have unique substrates in vivo, sumoylation of many substrates can be stimulated by either protein. Furthermore, in the absence of both Siz proteins, many of the same substrates are still sumoylated at low levels. Some of this residual sumoylation depends on MMS21. Siz1 targets its unique substrates through at least two distinct domains. Sumoylation of PCNA (proliferating cell nuclear antigen) and the splicing factor Prp45 requires part of the N-terminal region of Siz1, the ;PINIT\u27 domain, whereas sumoylation of the bud neck-associated septin proteins Cdc3, Cdc11 and Shs1/Sep7 requires the C-terminal domain of Siz1, which is also sufficient for cell cycle-dependent localization of Siz1 to the bud neck. Remarkably, the non-sumoylated septins Cdc10 and Cdc12 also undergo Siz1-dependent sumoylation if they are fused to the short PsiKXE SUMO attachment-site sequence. Collectively, these results suggest that local concentration of the E3, rather than a single direct interaction with the substrate polypeptide, is the major factor in substrate selectivity by Siz proteins
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