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.

Radiation-optical stability of single-mode W-type lightguides with depressed-index fluorosilicate cladding

Abstract: This paper discusses how hydrogen-isotope doping of a single-mode W-type fiber lightguide with fluorosilicate cladding affects its additional optical losses under bending of the fiber and γ irradiation. It is established that introducing stable OH− and OD− groups into the core of a lightguide fabricated by modified chemical vapor deposition reduces its optical losses when it is bent but does not increase the radiation–optical stability.

Подходы к снижению потерь на рассеяние излучения в полимерных планарных оптических волновода

Abstract: The article presents the development prospects of planar optical waveguides for high-speed data transmission systems optoelectronic buses by polymer materials. The advantages and disadvantages of using nonspecialized polymeric materials for general use are revealed. The polymer planar optical waveguides fabrication technologies are proposed. The main losses types in planar optical waveguides, the reasons for their occurrence, as well as approaches to their reduction are determined. Using the example of PDMS polymer and soft lithography technology, the technological process critical stages of polymer planar optical waveguides production are noted, which contribute to an scattering losses increase. For each stage, algorithms are proposed to prevent an scattering losses increase. These algorithms were implemented in practice in the manufacture of layouts of polymer planar optical waveguides of the optical-electronic data transmission bus.

Quo vadis, humanity? Ethics on the last mile toward cybernetic organism

Abstract: Motivated by the recent decisive progress in the field of the Internet of Bio-Nano Things (IoBNT), and fueled by the growing social importance of emerging services and applications built on...

Polynomial, Neural Network, and Spline Wavelet Models for Continuous Wavelet Transform of Signals.

Abstract: In this paper a modified wavelet synthesis algorithm for continuous wavelet transform is proposed, allowing one to obtain a guaranteed approximation of the maternal wavelet to the sample of the analyzed signal (overlap match) and, at the same time, a formalized representation of the wavelet. What distinguishes this method from similar ones? During the procedure of wavelets’ synthesis for continuous wavelet transform it is proposed to use splines and artificial neural networks. The paper also suggests a comparative analysis of polynomial, neural network, and wavelet spline models. It also deals with feasibility of using these models in the synthesis of wavelets during such studies like fine structure of signals, as well as in analysis of large parts of signals whose shape is variable. A number of studies have shown that during the wavelets’ synthesis, the use of artificial neural networks (based on radial basis functions) and cubic splines enables the possibility of obtaining guaranteed accuracy in approaching the maternal wavelet to the signal’s sample (with no approximation error). It also allows for its formalized representation, which is especially important during software implementation of the algorithm for calculating the continuous conversions at digital signal processors and microcontrollers. This paper demonstrates the possibility of using synthesized wavelet, obtained based on polynomial, neural network, and spline models, during the performance of an inverse continuous wavelet transform.

Selective image authentication tolerant to JPEG compression

Abstract: A watermark application in the integrity maintenance and verification of associated images is considered. There is a great advantage of watermark use in the context of conventional authentication since it does not require additional storage space for supplementary metadata. However JPEG compression, being a conventional method to compress images, leads to breaking of exact authentication. The usage of occuring selective authentication, tolerant to JPEG compression, is proposed. This technique is based on execution of Zernike moments. The performance evaluation of the proposed method depending on a compression factor is estimated. Simulation results show a good efficiency of this approach, including resistance to malicious attacks rather important within the frame of Security and Privacy in Future Generation Services topics.