THE RESULTS OF THE MULTI-POSITION SURVEILLANCE SYSTEM’S EFFICIENCY, DEPENDING ON THE LOCATIONS OF ITS SENSORS, USING ADDITIONAL DATA PROCESSING Volodymyr Tymchuk, Oleksandr Mediakov, Oleksandr Popov, T. Trysnyuk, Serhii Tsybulia System Research and Information Technologies, 2025 The efficiency of a multi-position system depends on the realization of its struc-ture — how many elements it includes, where they are located, and how the envi-ronment and terrain influence its operation. The paper is dedicated to data pro-cessing in a multi-position surveillance system as an additional option, leverag-ing the in-between big data from the system’s elements. A sufficient number of numerical data generated by the multi-position system and its elements–sensors–allows the use of statistical methods and models from machine learning or deep learning. The ontology for quality estimation of the multi-position sys-tem, depending on its configurations, is proposed. The results of the distribu-tions of detected events are presented in graphical forms that allow statistical evaluation of the distributed data. Our findings allow us to ensure the efficiency of a multi-position system in an unpredictable, variable environment by recon-figuring it when it offers better capabilities.
Fault Tolerance Exploration and SDN Implementation for de Bruijn Topology based on betweenness Coefficient , Artem Volokyta, Heorhii Loutskii, Oleksandr Honcharenko, Oleksii Cherevatenko, Volodymyr Rusinov, Yurii Kulakov, Serhii Tsybulia International Journal of Computer Network and Information Security, 2024 This article considers the method of analyze potentially vulnerable places during development of topology for fault-tolerant systems based on using betweenness coefficient. Parameters of different topological organizations using De Bruijn code transformation are observed. This method, assessing the risk for possible faults, is proposed for other topological organizations that are analyzed for their fault tolerance and to predict the consequences of simultaneous faults on more significant fragments of this topology.
DEVISING A METHOD FOR INTEGRATED DATASET FORMATION AND SELECTING A MODEL FOR RECOGNIZING THE TECHNICAL CONDITION OF UNMANNED AERIAL VEHICLE Oleksandr Perehuda, Andrii Rodionov, Dmytro Fedorchuk, Serhii Zhuravskyi, Mykola Konvisar, Taras Volynets, Vitalii Datsyk, Mykola Zakalad, Serhii Tsybulia, Taras Trysnyuk Eastern European Journal of Enterprise Technologies, 2024 The object of this study is the process of forming a training dataset for diagnosing the technical condition of unmanned aerial vehicles (UAVs) using machine-learning algorithms. UAV flights are extremely important for various aspects of troop deployment. Combat UAV flights are performed under the influence of negative factors that cause flight special cases (FSC), which hinder the execution of combat missions, lead to mission failures, and result in the aircraft damage or loss. The available capabilities of autopilots are not enough for control under complex conditions, and in certain situations, the human operator cannot timely recognize a flight special case, including evaluation of the destructive impact of enemy’s electronic warfare systems on communication channels and operation of UAV. Therefore, the urgent issue is the intellectualization of onboard control systems, particularly towards recognizing the current technical state of UAV using artificial intelligence methods. To design such systems, labeled datasets are required. The procedure for forming datasets that consider the specificity of UAV construction and their combat use under adversarial conditions is not defined, necessitating the development of an appropriate method. Based on the well-known CRISP-DM methodology, a method for dataset formation has been proposed for subsequent use in artificial intelligence systems that use various machine-learning methods. This method differs from existing ones by considering the specificity of combat mission execution under adversarial conditions, which allowed for an 8.0 % increase in the accuracy of recognizing special cases in UAV flights by the onboard system. It also enabled timely detection of electronic warfare impacts on UAV and evaluation of the effectiveness of radio signal receivers jamming
Optical spatial dispersion in terms of Jones calculus S. Yu. Nastyshyn, I. M. Bolesta, S. A. Tsybulia, E. Lychkovskyy, Z. Ya. Fedorovych, D. Ye. Khaustov, Ye. Ryzhov, P. I. Vankevych, Yu. A. Nastishin Physical Review A, 2019 Traditionally, optical spatial dispersion (OSD) is defined as the dependence $\stackrel{\ifmmode \hat{}\else \^{}\fi{}}{\ensuremath{\varepsilon}}(\stackrel{P\vec}{k})$ of the dielectric permittivity tensor $\stackrel{\ifmmode \hat{}\else \^{}\fi{}}{\ensuremath{\varepsilon}}$ on the light wave vector $\stackrel{P\vec}{k}$, similarly to the frequency ($\ensuremath{\omega}$) dispersion of the dielectric tensor $\ensuremath{\varepsilon}(\ensuremath{\omega})$. We have developed an approach for the description of the OSD phenomena in the framework of Jones calculus. In Jones calculus the differential Jones matrix (DJM) $N$ is the generalization of the light wave-vector $\stackrel{P\vec}{k}$ in the same sense that $\stackrel{P\vec}{k}$ is the generalization of the light wave number $k$. The latter inspires us to expect that there must exist a way to describe the OSD phenomena in terms of the DJM. We show that such a relation between the OSD phenomena and Jones calculus indeed exists. To prove the latter we derive a general relation between the DJM and components of the dielectric permittivity tensor $\stackrel{\ifmmode \hat{}\else \^{}\fi{}}{\ensuremath{\varepsilon}}$. We establish the relation of the DJM approach, proposed in this paper, to the traditional OSD approach of the gyration pseudotensor as well as to that developed by Mauguin for light propagation in cholesteric liquid crystals [M. C. Mauguin, Bull. Soc. Fr. Mineral. Crystallogr. N3, 71 (1911)]. We demonstrate that both the gyration pseudotensor and Mauguin's approach can be derived as particular cases of the proposed DJM approach. In our approach the integral Jones matrix (IJM) of the medium taking into account OSD is the product of the IJM without taking into account OSD by the correction IJM, which accounts for the OSD effects. In a general case, when all components of the OSD DJM ${N}^{D}$ are nonzero, the secular equation for the refractive indices of the eigenwaves is a quartic equation. The coefficient ${a}_{3}$ at the cubic term in the secular equation is nonzero only for nonzero OSD corrections to the average refractive index. For transparent crystals at nonzero OSD correction to the average refractive index and zero to all other correction parameters in ${N}^{D}$, the secular equation has two distinct real and two complex-conjugate roots. We assign the complex-conjugate roots to the forward and backward light scattering. Therefore, taking into account the OSD effect on the refractive index, the Jones calculus becomes capable of describing light scattering. The proposed Jones calculus approach is a general tool for taking into account OSD in optically inhomogeneous media, in which several or all OSD correction parameters are simultaneously nonzero, for example, in liquid-crystal cells with a spatially nonuniform director field, including those containing defects.
Differential and integral Jones matrices for a cholesteric S. Yu. Nastyshyn, I. M. Bolesta, S. A. Tsybulia, E. Lychkovskyy, M. Yu. Yakovlev, Ye. Ryzhov, P. I. Vankevych, Yu. A. Nastishin Physical Review A, 2018 Previous attempts to derive the differential Jones matrix (DJM, $N)$ by Jones [Jones, J. Opt. Soc. Am. 38, 671 (1948)] for a twisted crystal and the integral Jones matrix (IJM, $J)$ by Chandrasekhar and Rao [Chandrasekhar and Rao, Acta Crystallogr. A 24, 445 (1968)] for a cholesteric liquid crystal resulted in Jones matrices, which are valid for the spectral range except the selective light reflection band. We argue that the limitation of their validity is rooted in two key assumptions used in both approaches, namely, (1) local (nonrotated) DJM ${N}^{0}$ and the elementary IJM ${J}^{0}$ (to which the cholesteric is split) are those of a uniform nematic and (2) under rotation of the coordinate system, ${N}^{0}$ and ${J}^{0}$ obey the similarity transformation rule, namely, $N=R{N}^{0}{R}^{\ensuremath{-}1}$ and $J=R{J}^{0}{R}^{\ensuremath{-}1}$, where $R$ is the rotation matrix. We show that both of these assumptions are of limited applicability for a cholesteric, being justified only for weak twist. In our approach, the DJM and IJM are derived for a cholesteric without these assumptions. To derive the cholesteric DJM, we have established the relation between the diagonal form ${N}^{0d}$ of ${N}^{0}$ and Mauguin solutions [Mauguin, Bull. Soc. Fr. Mineral. Crystallogr. N\ifmmode^\circ\else\textdegree\fi{} 3, 71 (1911)] of Maxwell equations for eigenwaves propagating in the cholesteric. Namely, the eigenvalues of ${N}^{0}$ appear to be the wave numbers for the two eigenwaves propagating in the sample. Then the form of ${N}^{0}$ reconstructs from its diagonal form ${N}^{0d}$. Our DJM and IJM, derived for a general case of any ellipticity value of the eigenwaves, correspond to an optically anisotropic plate possessing gyrotropy, linear birefringence, and Jones dichroism. In the limiting approximations of circularly polarized eigenwaves and that corresponding to the Mauguin regime, the DJM and IJM reduce to those known from the literature. We found that the form of the transformation rule for the local DJM ${N}^{0}$ under rotation of the coordinate system depends on the regime of light propagation, being different from the similarity transformation rule alluded to above, but reduces to it at weak twist corresponding to the Mauguin regime.
