St. Petersburg State University of Telecommunications

About: St. Petersburg State University of Telecommunications is a education organization based out in Saint Petersburg, Russia. It is known for research contribution in the topics: Computer science & The Internet. The organization has 408 authors who have published 465 publications receiving 2160 citations.

On the negative Pell equation

Abstract: Let e be the fundamental unit of a field $$ Q\left( {\sqrt {d} } \right) $$ . In the paper, it is proved that e > d 3/2/ log2 d for almost all d such that N(e) = −1. Bibliography: 6 titles.

Identification System Model for Energy-Efficient Long Range Mesh Network Based on Digital Object Architecture

Abstract: The analysis of the possibility of building a system for identifying Internet of Things devices based on the Digital Object Architecture in mesh networks is given. The basic principles of the LPWAN networks and mesh networks are described. A brief overview of Digital Object Architecture technology is given. Schemes for integration of the Digital Object Architecture platform into mesh network are proposed. Various configuration options for this system in order to increase productivity are considered. The model of the Handle resolution system for identifiers of digital objects in mesh networks as a queuing system is proposed. An analysis of the results is given.

Implementation of a Multilayer Perceptron and Wavelet-Neural Network on a Microcontroller with Ultra-Low Power Consumption in Control and Signal Analysis Systems

Abstract: The paper has a practical focus and is dedicated to the implementation of a multilayer perceptron and wavelet- neural network on an ultra-low power consumption microcontroller MSP430G2553. A description of the implementation technologies of these neural networks is given, taking into account the limitations of the element base when solving the approximation problem. Comparison of neural networks implemented on the microcontroller showed that the wavelet-neural network allows to obtain a smaller approximation error compared to the perceptron. The comparison results also showed that with an equal number of neurons and the same number of iterations, the training speed of a multilayer perceptron is 2,15 times higher than that of a wavelet-neural network.

Stereotypic idea of a tom-cat and a cat through the prism of comparative phraseological units of russian and swedish languages

Abstract: The article attempts to identify the stereotypic idea of widespread domestic animals (a tomcat and a cat) on the material of similes of Russian and Swedish languages that characterize humans. The objective of the study is to identify the dominant characteristics of the “tom-cat” and “cat” in the Russian language picture of the world, which serve to assess a person, against the Swedish background. The sources of the material were dictionaries of Russian similes, the Swedish Phraseological Dictionary, data of the Russian National Corpus and the Swedish National Corpus. The main methods used in the study are methods of complete and directed material sampling, lexicographical, contextual and comparative analysis. This is an ideographic classification of Russian idioms, which allows to reveal comparison signs relevant for the Russian language picture of the world. The article identifies the dominant comparison bases in each group, indicating the importance of the corresponding attribute for native speakers. It analyzes gender distinctions in the use of Russian phraseological units with the “tom-cat” and “cat” reference standards, and peculiarities of using Russian similes in fiction contexts. A contrastive analysis is carried out with Swedish comparative phraseologisms with the standard “en katt”. The novelty of the study is to identify similar and different characteristics that allow to make a “portrait” description of domestic animals that serve as standards of similes, to identify relevant features for Russian and Swedish language pictures of the world. The study vector is directed from the standards of similes to their bases. As a result of the study, conclusions are drawn about the greater nominative density of idioms with “tom-cat / cat” components in Russian compared to Swedish, differences in gender relatedness due to the lack of generic differentiation of the Swedish standard of comparison, despite the fact that in Russian the replacement of the component “tom-cat” by “cat” leads to a change in the meaning of the phraseological unit, more detailed stereotypical representations in the Russian language particularly in such ideographic groups of similes as characteristics of appearance and behavior and to a greater peyorativity of Russian phraseological units compared to Swedish ones. The identified equivalent units in two languages, as well as the presence of the same ideographic groups of similes are due to the centuries-old observation of the peoples-speakers of languages for the universal features of the appearance and behavior of animals.

Silica microstructure-based optical fiber activated by YAG:Nd3+ nanocrystals

Abstract: The paper describes the polymer-salt method of neodymium-doped aluminum yttrium garnet (YAG:Nd) crystals formation inside the channels of a microstructured silica fiber preform. The crystals formation was performed through the impregnation of inner surfaces of the channels by aqueous solutions of thermally decomposable salts (yttrium nitrate, aluminum nitrate, neodymium chloride) and an organic polymer with subsequent processes of drying and thermal treatment at the temperature of 1100°C. The composite structure prepared was drawn into the fiber at the temperature of 2000°C. The X-ray diffraction analysis revealed the formation of YAG:Nd crystals from 25 nm to 37 nm in size in the silica glass matrix of the fiber. Measurement of the attenuation spectral dependence confirmed the presence of optical signal absorption bands inherent to Nd3+ ions. The shape of the nanocrystals luminescence spectrum is characteristic to the YAG:Nd with a peak at the wavelength of 1064 nm.