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Публікація Reversible luminescent hydrogen peroxide sensors based on CeO2-x and CeO2-x:Eu3+ nanocrystals(B. Verkin Institute for Low Temperature Physics and Engineering of NAS Ukraine, 2024) Maksimchuk, P.; Neuhodov, Y.; Hubenko, K.; Onishchenko, A.; Yefimova, S.; Seminko, V.Hydrogen peroxide (HP) is a widespread industrial chemical widely used for bleaching, cleaning, and disinfection. HP also plays an indispensable role in living organisms being a ubiquitous cell signaling molecule [1] and a substrate or byproduct of a number of enzymes (including catalase, superoxide dismutase, and a number of oxidases and peroxidases) [2]. So, HP sensing is required for reliable quantification of HP content in these systems.Публікація Second-Order Fractals in the Geospace Researches(Astronomy and Space Physics in the Kyiv University, 2023) Chernogor, L. F.; Lazorenko, O. V.; Onishchenko, A. A.According to the non-linear and the system paradigms, many processes generated in open, non-linear, dynamical systems under influence of a powerful source of energy release are appeared to be short-time, ultra-wideband, nonlinear and fractal. The geospace was shown to be a good example of such systems. Many processes caused in geospace by the non-stationary powerful sources of energy release have significant fractal properties. Therefore, the investigations of such properties seems to be actual and interestingПублікація GdVO4:Eu3+ Nanocrystals as catalase mimics for hydrogen peroxide decomposition(Ivan Franko National University of Lviv, 2024) Maksimchuk, P.; Hubenko, K.; Onishchenko, A.; Kavok, N.; Dudetskaya, G.; Seminko, V.; Yefimova, S.Hydrogen peroxide (H2O2) belongs to the family of reactive oxygen species and is vital for many redox metabolic reactions and cellular activities. It plays an important role in maintaining cellular homeostasis and influencing various physiological functions [1]. However, the reaction known as Fenton's reaction, which occurs between H2O2 and Fe2+ ions, is a significant contributor to the oxidation of biomolecules, resulting in the production of highly reactive hydroxyl radicals (•OH). This has led to increased interest in the development of preventive antioxidants that can interact with H2O2 without forming harmful radicals such as •OHПублікація Catalase-like hydrogen peroxide decomposition by GdVO4 :Eu3+ nanocrystals(2024) Maksimchuk, P.; Hubenko, K.; Onishchenko, A.; Seminko, V.; Yefimova, S.Hydrogen peroxide (H2O2) is a member of the reactive oxygen species family and plays a critical role in numerous redox metabolism reactions and cellular processes. It is considered a key component in the homeostatic metabolism of cells, mediating various physiological processes. However, the Fenton reaction between H2 O2 and Fe2+ ions is a major cause of biomolecule oxidation reactions, leading to the formation of highly reactive hydroxyl radicals (•OH). Therefore, there is significant interest in preventive antioxidants that can react with H2O2 without generating free radicals like •OHПублікація Multi-Fractal Analysis in Problems of the Applied Physics(Taras Shevchenko National University of Kyiv, 2023) Chernogor, L. F.; Lazorenko, O. V.; Onishchenko, A. A.According to the non-linear and the system paradigms, many processes generated in open, non-linear, dynamical systems under influence of a powerful source of energy release are appeared to be short-time, ultrawideband, non-linear and fractal. In the paper [1] published one year ago, we have introduced a short review of the existing mono-fractal analysis methods, which can be useful and quitly applicable for solving of the applied physics problems, where there are a lot of such processes and such systems. To investigate their fractal properties more extended, the multi-fractal analysis methods should be applied. Unfortunately, similar the monofractal analysis methods, these methods are often appeared to be quite unknown for the most part of researchers too.Публікація Effect of Hydrogen Peroxide Decomposition on Luminescence and Microstructure of GdVO4:Eu3+ Redox-Active Nanocrystals(Institute of Electronics and Computer Sciences, 2024) Hubenko, K.; Maksimchuk, P.; Klochkov, V.; Onishchenko, A.; Yefimova, S.Публікація Radioprotective Properties of Oxide Nanocrystals(University of Milano, 2024) Hubenko, K.; Maksimchuk, P.; Klochkov, V.; Bespalova, I.; Onishchenko, A.; Demchenko, L.; Yefimova, S.Публікація Fractal analysis in space physics(Taras Shevchenko National University of Kyiv, 2022) Chernogor, L. F.; Lazorenko, O. V.; Onishchenko, A. A.According to the non-linear and the system paradigms, many processes generated in open, non-linear, dynamical systems under influence of a powerful source of energy release are appeared to be short-time, ultrawideband, non-linear and fractal. In applied physics, there are a lot of such processes and such systems. Therefore, to investigate the fractal properties of the signals and processes generated in the open, non-linear, dynamical systems, the set of corresponding methods are needed. Namely such modern and effective methods had been united in fractal analysis. Suddenly, but these methods are often appeared to be quite unknown for the most part of researchers, which work in space physics. No doubt, this state should be changed.Публікація Fractal and Multi-Fractal Analyses of the Geomagnetic Field Variations Caused by the Earthquake on January 24, 2020 in Turkey(Eskisehir Technical University, 2022) Onishchenko, A.; Chernogor, L.; Lazorenko, O.Fractal and multi-fractal properties of the Earth’s magnetic field time variations caused by the earthquake took place on January 24, 2020 in Turkey were investigated. Using the Dynamical Fractal Analysis method proposed by the authors for both (D and H) horizontal components of geomagnetic field, the time dependences for the Hurst fractal dimension were obtained. With usage of the Wavelet Transform Module Maxima method and the Multi-Fractal Detrended Fluctuation Analysis method, the set of traditional and original multi-fractal numerical characteristics was estimated. Combining the fractal and multi-fractal analyses results with ones for the time-frequency structure, obtained the Continuous Wavelet Transform application, the set of disturbances caused by the earthquake was discovered. For these disturbances, all needed time-frequency, fractal and multifractal characteristics were estimated. The disturbances were shown to be fractal ultra-wideband processes with complex, non-stationary multi-fractal structure. Two promising candidates for the role of earthquake harbingers were revealed. One possible earthquake harbinger in both horizontal components of the geomagnetic field time variations seems to be detected. This harbinger was shown to be registered 25.5 hours before the earthquake event. Being be found in time variations of the multifractal characteristics only for both horizontal components of the geomagnetic field, another possible earthquake harbinger took place 0.5 hours before the earthquake event. The so-called transition of the multifractal process to the mono-fractal mode was detected. For both harbingers, the time-frequency, fractal and multifractal characteristics were estimated.Публікація Fractal Analysis in Problems of the Applied Physics(Taras Shevchenko National University of Kyiv, 2022) Chernogor, L. F.; Lazorenko, O. V.; Onishchenko, A. A.For the researchers, a review of the existing mono-fractal analysis methods applied in different branches of modern applied physics is proposed. For each mono-fractal analysis method, some actual references allowing to study the method and to develope corresponding numerical realization are givenПублікація Резонансная кубическая решетка сферических воздушных пузырьков, находящаяся в магнито-диэлектрической среде(Вебер, 2010) Козарь, А. И.Рассматривается решение и анализ задачи о рассеянии плоской электромагнитной волны резонансной кубической решеткой сферических воздушных пузырьков, находящихся в магнитодиэлектрической среде с большим значением диэлектрической и магнитной проницаемостями.Публікація Hydrogen Peroxide Detection Using Reversible Luminescent CeO2-x and CeO2-x:Eu3+ Nanocrystals(Institute of Physics of the National Academy of Sciences of Ukraine, Taras Shevchenko National University of Kyiv Ukrainian, Physical Society, 2024) Maksimchuk, P.; Neuhodov, Y.; Hubenko, K.; Onishchenko, A.; Kavok, N.; Dudetskaya, G.; Kot, Y.; Yefimova, S.; Seminko, V.Hydrogen peroxide (HP) is a prevalent industrial chemical used extensively for bleaching, cleaning, and disinfection. In biological systems, HP acts as a crucial signaling molecule and is involved in various enzymatic processes as a substrate or byproduct, such as those involving catalase, superoxide dismutase, and numerous oxidases and peroxidases [1, 2]. Thus, precise HP sensing is vital for monitoring its concentration in both industrial and biological contextsПублікація Time-Frequency and Fractal Analyses of the Earth's Magnetic Field Variations Appeared During Powerful Geospace Storms Took Place in September 2017(Taras Shevchenko National University of Kyiv Astronomical Observatory, 2021) Chernogor, L.; Lazorenko, O.; Onishchenko, A.According to the non-linear and the system paradigms, many processes generated in open, non-linear, dynamical systems under influence of a powerful source of energy release are appeared to be short-time, ultrawideband, non-linear and fractal.Публікація Comparative analysis of models for short-term forecasting of electricity consumption(2024) Korablyov, M.; Kobzev, I.; Chubukin, O.; Antonov, D.; Polous, V.; Tkachuk, O.Forecasting electricity consumption is an urgent task, and the solution significantly affects the efficiency of the use of energy resources. The paper considers short-term forecasting of electricity consumption, which predicts the amount of energy that will be used in a short period, from several hours to several days in advance. There are various short-term forecasting models, so it is important to reasonably choose a model that provides analysis and effective forecasting of electricity consumption to optimize the use of energy resources. The purpose of the work is to analyze the main forecasting models, such as statistical models (autoregressive model, moving average, exponential smoothing, moving average with autoregression and integration) and deep learning models (artificial neural network, recurrent neural network, long short-term memory, transformer), indicating their advantages and disadvantages, and choosing the best of them. The experimental results of a comparative analysis of power consumption forecasting models are presented, which showed that the transformer model was 1.5% - 2% more effective in power consumption forecasting according to various metrics. Its higher level of accuracy, reflected in low error values and high coefficient of determination, indicates its high adaptability to the dynamics of electricity consumption.Публікація Immune Model for Controlling Characters in Computer Games(CEUR Workshop Proceedings (CEUR-WS.org), 2023) Korablyov, M.; Fomichov, O.; Chubukin, O.; Antonov, D.; Dykyi, S.The rapid development of information technologies led to the emergence of new opportunities for game software developers. In the field of game application development, a large number of platforms and patterns of architecture development, as well as game environments, have appeared, which allow simplifying and automating the process of development and deployment of the game software. The game application used in the work simulates a futuristic space world where the player interacts with other characters in a free game space. An analysis of game resources, which can be controlled by the player and other game characters, has been carried out. The main features of the behavior of game characters controlling spaceships on the map of the game world are defined. The task of controlling the behavior of characters in game software can be considered as a classification problem, for which it is proposed to use artificial immune systems. Among the existing immune models, the most promising for practical application is the artificial immune network model, which was chosen as the basis for creating a model for controlling the behavior of characters in computer games. But it cannot be used to solve the problem of managing game characters without additional modifications. A modified model of the immune network – behavioral aiNET (baiNET) was proposed, which can be used to solve the problem under consideration. The software implementation of the game software tool, in which the control of the game characters is carried out using the baiNET model, has been completed. Experimental studies were carried out with different numbers of game characters on different-sized maps of the game world, which showed that the proposed baiNet immune model is effective and simple to implement and modify. This makes it possible to use it to control characters in games of other genres.Публікація Peculiarities of Cs1-xRbxCu2Cl3 Solid Solutions Absorption Spectra(Eskisehir Technical University, 2023) Kovalenko, O.; Yunakova, O.; Yunakov, N.Публікація Підвищення надійності недермінованих генераторів випадкових бітів(«P.C. Publishing House», 2024) Рибалка, А. І.; Торба, А. А.; Мегель, Ю. Є.Граничні характеристики стійкості систем криптографічного захисту інформації (КЗІ) досягаються в разі, якщо для формування ключів, параметрів і синхромаркерів використовується генератор випадкових бітів – ГВБ (або випадкових послідовностей – ГВП) на основі фізичних датчиків шуму з найкращими параметрами рівноймовірності, незалежності і некорельованості.Публікація Exciton absorption spectrum of thin films of (CsxK1-x)2CuCl3 solid solutions.(2024) Kovalenko, E. N.; Yunakova, O. N.; Yunakov, N. N.The absorption spectra of thin films of (CsxK1-x)2CuCl3 0≤х≤1 (T=90K) solid solutions in the spectral range 2–6 eV were studied. According to the analysis of the spectra, the formation of two types of compounds was observed and studied: 1) compounds at x=0 and in the range of 0.4≤х≤1 which are isostructural to Cs2CuCl3 and K2CuCl3; 2) compounds at x=0.2 which are isostructural to CsCu2Cl3. The excitonic spectra of (CsxK1-x)2CuCl3 0≤х≤1compounds are caused by transitions in the Cu+ ion. The linear concentration dependences of the spectral position of exciton bands in both types of compounds confirm the localization of excitons in sublattices containing Cu+ ions.Публікація Effect of scattering on the transmission spectra of crystalline p-terphenil(Eskisehir Technical University, 2024) Kovalenko, O.; Yunakova, O.; Makovetskyi, Y.; Yunakov, M.Interest in studying the transmission spectra of crystalline p-terphenyl is due to the possibility of creating effective scintillators based on it. The samples of large volume or large area are used for this purpose. The transmission spectra of crystalline p-terphenyl samples with a thickness of 2 and 4 mm and a diameter of 18 mm are studied in this work.Публікація Exciton absorption spectrum of thin films of ternary compounds in the CsCl-CuCl system(Фізико-технічний інститут низьких температур імені Б. І. Вєркіна, 2023) Kovalenko, E. N.; Yunakova, O. N.; Yunakov, N. N.The absorption spectra of thin films (CsCl)1-x(CuCl)x were studied at T=90K in the spectral range 2 – 6 eV. From the analysis of the spectra, the formation of CsCu2Cl3 and Cs2CuCl3 compounds in the CsCl – CuCl system was established. The Cs2CuCl3 compound is stable only in a vacuum; in air, it apparently decomposes into CsCu2Cl3 with a disordered crystal lattice and CsCl. The exciton spectrum of both compounds is interpreted on the basis of transitions in the Cu+ ion. A one-dimensional (1D) character of excitons in CsCu2Cl3 and a two-dimensional (2D) character in Cs2CuCl3 was established