1,954 results on '"A Proskurin"'
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2. New strategy for boosting cathodic performance of low temperature solid oxide fuel cells via chlorine doping
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Xu, ShaoHua, Qiu, Hao, Jiang, Shanshan, Jiang, Jingjing, Wang, Wei, Xu, Xiaomin, Kong, Wei, Chivurugwi, Tanaka Dennis, Proskurin, Arkadii, Chen, Daifen, and Su, Chao
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- 2024
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3. Fast simulation of light scattering and harmonic generation in axially symmetric structures in COMSOL
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Gladyshev, Sergei, Pashina, Olesia, Proskurin, Alexey, Nikolaeva, Anna, Sadrieva, Zarina, Bogdanov, Andrey, Petrov, Mihail, and Frizyuk, Kristina
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Physics - Optics ,Physics - Computational Physics - Abstract
In the field of optics and nanophotonics, simulation of electromagnetic scattering plays a major role in the study of complex nanostructures and optical devices. The numerical analysis of scattering spectra, even for nanocavities with simple geometry, is associated with significant computational difficulties. However, when the system exhibits certain symmetries, it becomes possible to simplify the problem through the process of separation of variables, which leads to a decrease in its dimension. In this paper, we aim to provide a practical guide to a fast simulation of linear and non-linear scattering problems in COMSOL Multiphysics for axisymmetric objects including computation of scattering cross-section as well as its multipolar decomposition, optical forces, and second harmonic generation. We also accompany the provided guide with the ready-to-run COMSOL models.
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- 2023
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4. Analysis of Syngas Combustion Process in Piston Engines
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Mytrofanov O., Proskurin A., and Kong W.
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alternative fuel ,syngas ,combustion heat release characteristics ,working process ,combustion index ,combustion duration. ,Electrical engineering. Electronics. Nuclear engineering ,TK1-9971 ,Production of electric energy or power. Powerplants. Central stations ,TK1001-1841 ,Renewable energy sources ,TJ807-830 - Abstract
The article examines the features of the combustion process of hydrogen-containing gas (syn-gas) in the working cylinder of a spark-ignition internal combustion engine. The main objective of the study is to evaluate the heat release parameters of syngas. To achieve this goal, an exper-imental investigation was conducted to assess the nature of syngas combustion and establish its regularity. The most significant result is the derivation of dependencies for determining the cur-rent value of the combustion characteristic index m and the combustion duration φz in Professor I.I.Vibe's heat release model for spark-ignition engines operating on syngas, with an air excess ratio α ranging from 1.0 to 2.2 and hydrogen content in the fuel composition varying between 30% and 100% by volume. The significance of the obtained results lies in the establishment of the variability of the combustion index m (ranging from 1.6 to 5.5) in Professor I.I.Vibe's semi-empirical heat release model, which more closely corresponds to the actual heat release law ob-served in experimental studies. The proposed dependencies for determining m and φz allow for accounting the specific features of the syngas combustion process in spark-ignition engines, thereby significantly improving the accuracy of determining the indicated pressure in the work-ing cylinder (the relative root-mean-square error does not exceed 4.5%), which, in turn, enhanc-es the accuracy of assessing the engine's energy and economic parameters. The results of this study can be applied in the design and construction of new spark-ignition engines running on alternative fuel.
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- 2024
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5. Antenna array of waveguide horns with an E-plane aperture, as well as horns with an aperture in the E- and H-planes
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Yuri G. Pasternak, Vladimir A. Pendyurin, Dmitry K. Proskurin, and Kirill S. Safonov
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mobile and airborne satellite communications ,linear antenna arrays ,waveguide horns ,Physics ,QC1-999 ,Electronics ,TK7800-8360 - Abstract
Background. Currently, in connection with the conduct of a special military operation, the issue of the availability of inexpensive mobile terminals for high-speed satellite communications of domestic production is very relevant, as well as due to the large extent of the territories of our country, there are a number of areas where cellular communication is absent, for example, the Taiga, the Arctic, the territory of the Arctic Ocean, etc. Therefore, the only possible connection in these territories is satellite communication. Aim. Development of a linear equidistant antenna array with equal amplitude and common-mode excitation for a mobile satellite communication terminal. Methods. The antenna array was designed from the open ends of waveguides with a cross section of 19 × 11 mm with air filling. Adjacent pairs of radiating waveguides are powered by an E-planar divider: the waveguide is divided in half in height by a thin metal diaphragm, wave reflections from which are insignificant; further, in each half of the power divider, height-separated right and left turns and smooth transitions in the E-plane are implemented – an extension from 5,25 mm to 11 mm. Results. An antenna array with a period of 19,5 mm has been developed. Overall dimensions: opening width – 624 mm, height – 12 mm, depth – 118 mm. A feature of the antenna array design is the use of smooth asymmetric transitions in the E-plane according to the exponential law; in the opening of the headlights, waveguide asymmetric horns alternate, with a period equal to 4 values of the width of the waveguides, taking into account the width of their narrow walls, expanding in the upper (2 adjacent radiators) and lower (next 2 radiators) directions. Conclusion. The advantage of using an approach to the construction of linear antenna arrays powered by multichannel power dividers is the ability to minimize the depth of the antenna system. The main disadvantages are the constructive and technological complexity of power dividers and significant power losses with a large number of channels. Possible manufacturing technologies of the developed phased array: 1. Stamping of polystyrene of the inner part of the power divider and emitters. Next, polishing, copper spraying and electroplating with a layer of copper. 2. Printing on a 3D polystyrene printer, polishing, copper spraying and copper electroplating. 3. Manufacture of a power divider using SIW technology based on standard microwave laminates. The use of metallized through holes for matching power dividers. Antenna elements and coaxial waveguide junctions are made by stamping from polystyrene, or printing on a 3D printer from polystyrene, then polishing, spraying a layer of copper and electroplating with a layer of copper. 4. Metal stamping of the power divider, emitters and coaxial waveguide junctions (2 parts). The dielectric insert can be printed on a 3D printer made of polystyrene.
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- 2024
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6. Predicting pseudo-random number generator output with sequential analysis.
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Dmytro Proskurin, Maksim Iavich, Tetiana Okhrimenko, Okoro Chukwukaelonma, and Tetiana Hryniuk
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- 2024
7. Hybrid RNN-CNN-based model for PRNG identification (short paper).
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Dmytro Proskurin, Tetiana Okhrimenko, Sergiy Gnatyuk, Dauriya Zhaksigulova, and Nataliia Korshun
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- 2024
8. Minimizing bulk oxygen transport resistance of PEMWE by adding PTFE to tuning wettability and pore size in the anode catalyst layer
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Han, Chenhui, Bian, Ting, Proskurin, Arkadii, Senin, Petr, Kong, Wei, and Chen, Daifen
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- 2025
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9. Achieving solid-state room temperature dehydrogenation from sodium borohydride composited with glycolic acid
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Tang, Deyu, Zheng, Jiaguang, Yan, Chengguo, Xia, Ao, Kong, Wei, Proskurin, Arkadii, and Wang, Xiuzhen
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- 2025
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10. Constructing a Schottky heterostructure CoNi-CoOx catalyst with mass active area by manipulating the content of CoO for efficient hydrogen production
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Lu, Zichuan, Li, Shuai, Zhong, Tao, Zhou, Ren, Wu, Fuying, Chen, Daifen, Kong, Wei, Proskurin, Arkadii, and Zhang, Liuting
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- 2025
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11. Development and construction of a mechanized moving platform for human service
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Volodymyr Rashkivskyi, Mykola Prystailo, Bohdan Fedyshyn, Iryna Dubovyk, and Oleksiy Proskurin
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human service ,operational safety ,mechanized equipment ,platform ,energy recovery ,sustainability ,Technological innovations. Automation ,HD45-45.2 ,Mechanical industries ,HD9680-9714 ,Instruments and machines ,QA71-90 ,Descriptive and experimental mechanics ,QC120-168.85 ,Information technology ,T58.5-58.64 ,Materials of engineering and construction. Mechanics of materials ,TA401-492 ,Mining engineering. Metallurgy ,TN1-997 ,Earthwork. Foundations ,TA715-787 - Abstract
The purpose of the proposed article is the development and construction of a mechanized mobile platform for serving people, which is caused by the need to increase the safety of the operation of such technical means, in particular, in the case of the need for mass customer service. The methodology is based on search, research and creative approaches. The methods of development analysis, patent search, synthesis of technical solutions, simulation modelling was used. Scientific novelty. The study of the features of various approaches to the creation of effective mechanized moving platforms, the analysis of solutions and the dynamics of patenting made it possible to substantiate the directions of development of technical solutions and the prospects of developments. The authors proposed constructive solutions for mobile platforms, developed approaches to the technical implementation of increasing the safety of their operation, proposed energy-saving approaches aimed at reducing the energy consumption of mechanized means, which is especially relevant in the mass implementation of platforms for serving people. Research results. The article solves important safety issues of human service, in particular in the entertainment industry through the development of structural parts, drives and rules for the operation of mechanized moving platforms. Synthesized constructive solutions obtained in the course of patent research, analysis of modern technical solutions, rational technical design, and expert evaluation are presented. It was determined that the safety of the operation of mechanized moving platforms, which are intended for the transport of people in the field of tourism, depends on effective approaches to the design and components of the technical system in the form of a moving platform, its structural components, elements of its mechanism and the drive system as a whole, which with the optimization of technical indicators the stability of the overall system, the smoothness of movement and braking of the platform, the optimization of the materiality of the structure in total allow to have a qualitative effect on improving the safety of human operation.
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- 2024
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12. Polynomial Threshold Functions for Decision Lists
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Podolskii, Vladimir and Proskurin, Nikolay V.
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Computer Science - Computational Complexity - Abstract
For $S \subseteq \{0,1\}^n$ a Boolean function $f \colon S \to \{-1,1\}$ is a polynomial threshold function (PTF) of degree $d$ and weight $W$ if there is a polynomial $p$ with integer coefficients of degree $d$ and with sum of absolute coefficients $W$ such that $f(x) = \text{sign}(p(x))$ for all $x \in S$. We study a representation of decision lists as PTFs over Boolean cubes $\{0,1\}^n$ and over Hamming balls $\{0,1\}^{n}_{\leq k}$. As our first result, we show that for all $d = O\left( \left( \frac{n}{\log n}\right)^{1/3}\right)$ any decision list over $\{0,1\}^n$ can be represented by a PTF of degree $d$ and weight $2^{O(n/d^2)}$. This improves the result by Klivans and Servedio [Klivans, Servedio, 2006] by a $\log^2 d$ factor in the exponent of the weight. Our bound is tight for all $d = O\left( \left( \frac{n}{\log n}\right)^{1/3}\right)$ due to the matching lower bound by Beigel [Beigel, 1994]. For decision lists over a Hamming ball $\{0,1\}^n_{\leq k}$ we show that the upper bound on weight above can be drastically improved to $n^{O(\sqrt{k})}$ for $d = \Theta(\sqrt{k})$. We also show that similar improvement is not possible for smaller degrees by proving the lower bound $W = 2^{\Omega(n/d^2)}$ for all $d = O(\sqrt{k})$. \end{abstract}, Comment: 14 pages in total (11 for article + 3 for references and appendix)
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- 2022
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13. Interfacial reconstruction of 2D/2D CuS/ZnIn2S4 through interface S-S bonds for boosted near-infrared driven photothermal-assisted photocatalytic hydrogen production
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Chen, Zhouze, Yan, Yujie, Shan, Pengnian, Bian, Ang, Kong, Wei, Proskurin, Arkadii, Guo, Li, Hou, Jianhua, Liu, Zhuo, Wang, Guangzhao, Shi, Weilong, and Lu, Changyu
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- 2024
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14. Antenna array of waveguide elements with dielectric phasing sections
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Yuri G. Pasternak, Vladimir A. Pendyurin, Dmitry K. Proskurin, and Kirill S. Safonov
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mobile and airborne satellite communications ,linear antenna arrays ,round waveguides ,Physics ,QC1-999 ,Electronics ,TK7800-8360 - Abstract
Background. The need to develop and continuously improve mobile and on–board high-speed satellite communication terminals, as well as satellite communication equipment with high secrecy of operation, emitting ultra-wideband signals, the spectral power density of which, measured at the input of receiving devices of radio monitoring complexes, should be significantly lower than the spectral power density of noise, is due to the following circumstances: ensuring reliable and high-quality communication military and civilian users; the development of the domestic element and technological base, import substitution; the need for rescue services in small-sized information transmission and reception systems; the need to develop satellite control systems for military and civilian equipment; the development of precision agriculture programs. An antenna array made of waveguide elements with dielectric phasing sections can serve as one such example. Aim. The model of the antenna element is considered, and its main characteristics are also given. A model of a linear antenna array consisting of 32 waveguide elements with phasing sections has been developed. Linear and flat antenna arrays based on a common-mode and equal-amplitude 1:32 power divider and antenna elements are considered. A model of a flat antenna array composed of 16 linear antenna arrays is also constructed and its main characteristics are given. Methods. The antenna element model is based on a circular waveguide with an internal diameter of 18 mm and a dielectric plate, the plane of which is oriented at an angle of 45° to the lines of force of the electric field intensity vector. The linear antenna array is powered by an equal amplitude and common-mode power divider, and the linear and flat antenna arrays are based on square waveguides with internal dimensions of 14×14 mm2 with beveled internal corners. Results. It is shown that the gain at a frequency of 10,95 GHz is 32,5 dB (normal) and 31,2 dB when the beam is deflected by ±37,5° in the angular plane. The gain at a frequency of 11,7 GHz is 33,8 dB (normal) and 32,5 dB when the beam is deflected by ±37,5° in the angular plane. With the maximum deviation of the main lobe from the normal, the level of the side lobes in the vertical increases to the level of -11,4 dB, which slightly exceeds the UBL with in-phase and equal amplitude field distribution in the headlight aperture (-13,2 dB). Conclusion. In the considered headlight design, the positioning of the main lobe of the radiation pattern in the azimuthal plane is carried out by mechanical rotation of the antenna system. The rejection of two–coordinate electronic scanning was chosen based on considerations of reducing phase shifters (or high-frequency switches) and reducing the cost of headlights.
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- 2024
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15. Mode attraction in Floquet systems with memory: application to magnonics
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Proskurin, Igor, Iyaro, Jephthah, and Stamps, Robert L.
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Condensed Matter - Mesoscale and Nanoscale Physics - Abstract
Level attraction is a type of mode hybridization in open systems where instead of forming a hybridization gap, the energy spectrum of two modes coalesce in a region bounded by exceptional points. We demonstrate that this phenomenon can be realized in a Floquet system with memory, which appears in describing linear excitations in a nonlinear driven system with a limit cycle. Linear response of the system in this state is different from its response near thermodynamic equilibrium. We develop a general formalism and provide an example in the context of cavity magnonics, where we show that magnetic excitations in systems driven far from the equilibrium may show level attraction with cavity photons. Our approach works equally well for quantum and semiclassical magnetic dynamics. The theory is formulated so that it can be used in combination with micromagnetic simulations to explore a wide range of experimentally interesting systems., Comment: Published version: 10 pages, 2 figures, PRB style
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- 2022
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16. On $q$-tensor products of Cuntz algebras
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Kuzmin, Alexey, Ostrovskyi, Vasyl, Proskurin, Danylo, Weber, Moritz, and Yakymiv, Roman
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Mathematics - Operator Algebras ,Mathematical Physics ,Mathematics - K-Theory and Homology ,Mathematics - Quantum Algebra ,46L05, 46L35, 46L80, 46L65, 47A67, 81R10 - Abstract
We consider the $C^*$-algebra $\mathcal{E}_{n,m}^q$, which is a $q$-twist of two Cuntz-Toeplitz algebras. For the case $|q|<1$, we give an explicit formula which untwists the $q$-deformation showing that the isomorphism class of $\mathcal{E}_{n,m}^q$ does not depend on $q$. For the case $|q|=1$, we give an explicit description of all ideals in $\mathcal{E}_{n,m}^q$. In particular, we show that $\mathcal{E}_{n,m}^q$ contains a unique largest ideal $\mathcal{M}_q$. We identify $\mathcal{E}_{n,m}^q / \mathcal{M}_q$ with the Rieffel deformation of $\mathcal{O}_n \otimes \mathcal{O}_m$ and use a K-theoretical argument to show that the isomorphism class does not depend on $q$. The latter result holds true in a more general setting of multiparameter deformations., Comment: Accepted to publication in International Journal of Mathematics. arXiv admin note: substantial text overlap with arXiv:1812.08530
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- 2021
17. A class of representations of $C^*$-algebra generated by $q_{ij}$-commuting isometries
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Ostrovska, Olha, Ostrovskyi, Vasyl, Proskurin, Danylo, and Samoilenko, Yurii
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Mathematics - Operator Algebras ,Mathematics - Representation Theory - Abstract
For $C^*$-algebra generated by a finite family of isometries $s_j$, $j=1,\dots,d$ satisfying $q_{ij}$-commutation relations \[ s_j^* s_j = I, \quad s_j^* s_k = q_{ij}s_ks_j^*, \qquad q_{ij} = \bar q_{ji}, |q_{ij}|<1, \ 1\le i \ne j \le d, \] we construct an infinite family of unitarily non-equivalent irreducible representations. These representations are deformations of the corresponding class of representations of the Cuntz algebra $\mathcal O_d$.
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- 2021
18. Duality in Language and Culture: Values and Meta-Concepts
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Sergey G. Proskurin and Anna V. Proskurina
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value ,concept ,meta-concept ,cognitive scenario ,binary oppositions ,duality ,History (General) ,D1-2009 ,Language and Literature - Abstract
Texts of language and culture have a dual organization. The conceptual core contains the values experienced by a culture bearer while the periphery contains meta-concepts that belong to an outside observer. Such duality produces paired concepts of faith – religion, justice – law, hope – prospects, life – existence, etc. This article introduces a new interpretation of duality – not as a binary opposition, but as a semantically close chain of terms and meta-terms. The authors classified texts as those based on value-concepts, meta-concepts, and a mix of the experiences that belong to the culture bearer and the meta-concepts that belong to the observer. The resulting semiotic historical-genetic method makes it possible to detect cultural phenomena and build thematic semantic networks of language and culture that update the values. This leads to permitted and prohibited term usage. For instance, a Russian speaker cannot say I'm goggling because the action described by predicate can be evaluated only by an outside observer. However, one can say he's goggling because this cognitive scenario presupposes an outside observer. Such taboos are associated with terms and meta-terms.
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- 2024
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19. Подражание италиянскому Александра Пушкина и Удавленник Николая Маркевича
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Oleg Proskurin
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александр пушкин ,николай маркевич ,данте ,самоубийца ,бесы ,рога ,Language and Literature - Abstract
В статье устанавливается возможный источник одного загадочного эпизода встихотворении Александра Пушкина Подражание италиянскому (1836). В этом эпизоде бесы поднимают труп Иуды нарога ис хохотом влекут его ксатане. Он отсутствует витальянском оригинале – сонете Sopra Giuda поэта Франческо Джанни (Francesco Gianni, 1750–1822) ивего французском переводе Антони Дешана (Antoni Deschamps, 1800–1869), послужившем непосредственным источником для подражания Пушкина. Такие бесы не существуют нивофранцузской, ни витальянской традиции. В статье высказано предположение, что Пушкин воспользовался для своей инновации стихотворением Удавленник украинского поэта иэтнолога Николая Маркевича (1804–1860), опубликованным вжурнале «Московский телеграф» в1829 году ивошедшем вего книгу Украинские мелодии в1831 году. Маркевич познакомился сПушкиным вМоскве в1829 году. В стихотворении самоубийцу уносят бесы «на роги». Украинские народные верования, поэтически обработанные Н. Маркевичем, оказывались пригодными для выражения особенностей итальянского средневекового сознания.
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- 2023
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20. Advancing the Pareto front for thin-film materials using a self-driving laboratory
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MacLeod, Benjamin P., Parlane, Fraser G. L., Rupnow, Connor C., Dettelbach, Kevan E., Elliott, Michael S., Morrissey, Thomas D., Haley, Ted H., Proskurin, Oleksii, Rooney, Michael B., Taherimakhsousi, Nina, Dvorak, David J., Chiu, Hsi N., Waizenegger, Christopher E. B., Ocean, Karry, Mokhtari, Mehrdad, and Berlinguette, Curtis P.
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Condensed Matter - Materials Science ,Physics - Applied Physics - Abstract
Useful materials must satisfy multiple objectives, where the optimization of one objective is often at the expense of another. The Pareto front reports the optimal trade-offs between competing objectives. Here we report a self-driving laboratory, "Ada", that defines the Pareto front of conductivities and processing temperatures for palladium films formed by combustion synthesis. Ada identified previously untested combustion synthesis conditions that resulted in the discovery of lower processing temperatures (below 200 {\deg}C) relative to the prior art for this technique (250 {\deg}C), a temperature difference that makes the coating of different commodity plastic materials possible (e.g., Nafion, polyethersulfone). These conditions enabled us to use combustion synthesis to spray coat uniform palladium films with moderate conductivity (1.1 $\times$ 10$^5$ S m$^{-1}$) at 191 {\deg}C. Spray coating at 226 {\deg}C yielded films with conductivities (2.0 $\times$ 10$^6$ S m$^{-1}$) comparable to those of sputtered films (2.0 to 5.8 $\times$ 10$^6$ S m$^{-1}$). This work shows how self-driving laboratories can discover materials satisfying multiple objectives.
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- 2021
21. ISLAB: Immutable Memory Management Metadata for Commodity Operating System Kernels.
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Marius Momeu, Fabian Kilger, Christopher Roemheld, Simon Schnückel, Sergej Proskurin, Michalis Polychronakis, and Vasileios P. Kemerlis
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- 2024
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22. SEVerity: Code Injection Attacks against Encrypted Virtual Machines
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Morbitzer, Mathias, Proskurin, Sergej, Radev, Martin, Dorfhuber, Marko, and Salas, Erick Quintanar
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Computer Science - Cryptography and Security - Abstract
Modern enterprises increasingly take advantage of cloud infrastructures. Yet, outsourcing code and data into the cloud requires enterprises to trust cloud providers not to meddle with their data. To reduce the level of trust towards cloud providers, AMD has introduced Secure Encrypted Virtualization (SEV). By encrypting Virtual Machines (VMs), SEV aims to ensure data confidentiality, despite a compromised or curious Hypervisor. The SEV Encrypted State (SEV-ES) extension additionally protects the VM's register state from unauthorized access. Yet, both extensions do not provide integrity of the VM's memory, which has already been abused to leak the protected data or to alter the VM's control-flow. In this paper, we introduce the SEVerity attack; a missing puzzle piece in the series of attacks against the AMD SEV family. Specifically, we abuse the system's lack of memory integrity protection to inject and execute arbitrary code within SEV-ES-protected VMs. Contrary to previous code execution attacks against the AMD SEV family, SEVerity neither relies on a specific CPU version nor on any code gadgets inside the VM. Instead, SEVerity abuses the fact that SEV-ES prohibits direct memory access into the encrypted memory. Specifically, SEVerity injects arbitrary code into the encrypted VM through I/O channels and uses the Hypervisor to locate and trigger the execution of the encrypted payload. This allows us to sidestep the protection mechanisms of SEV-ES. Overall, our results demonstrate a success rate of 100% and hence highlight that memory integrity protection is an obligation when encrypting VMs. Consequently, our work presents the final stroke in a series of attacks against AMD SEV and SEV-ES and renders the present implementation as incapable of protecting against a curious, vulnerable, or malicious Hypervisor.
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- 2021
23. Collective dynamics of domain walls: an antiferromagnetic spin texture in an optical cavity
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Iyaro, Jephthah, Proskurin, Igor, and Stamps, Robert L.
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Condensed Matter - Materials Science - Abstract
Spin canting and complex spin textures in antiferromagnetic materials can often be described in terms of Dzyaloshinskii-Moriya interactions (DMI). Values for DMI parameters are not easily measurable directly, and often inferred from other quantities. In this work, we examine how domain wall dynamics in an antiferromagnetic optomagnonic system can display unique features directly related to the existence of DMI. Our results indicate that the presence of DMI enables spin interactions with cavity photons in a geometry which otherwise allows no magneto-optical coupling, and on the other hand modulates frequencies in a geometry where coupling is already realized in the absence of DMI. This result may be used to measure the DMI constant in optomagnonic experiments by comparing resonances obtained with different polarisations of the exciting field.
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- 2021
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24. Тяжкий млат (О генезисе одного образа в «Полтаве»)
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Proskurin, Oleg
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- 2023
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25. Hierarchical structure design of MoS2/PDA/Ag-hybrid hydrogel system enhances all-environment solar water purification
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Cheng, Long, Li, Chengping, Wu, Xingqiao, Wang, Ziyi, Zhang, Liuting, Kong, Wei, Wang, Liang, Senin, Petr, Proskurin, Arkadii, and Bian, Ting
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- 2025
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26. Linear stability of flow in a 90-degree bend
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Proskurin, Alexander
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Physics - Fluid Dynamics - Abstract
The paper considers a two-dimensional flow in a channel, which consists of straight inlet and outlet branches and a circularly 90-degree curved bend. An incompressible viscous fluid flows through the elbow under the action of a constant pressure gradient between the inlet and outlet. Navier-Stokes equations were solved numerically using a high-fidelity spectral/hp element method. In a range of Reynolds numbers, an adaptive selective frequency dumping method was used to get a steady-state flow. It was found that three separation bubbles and vortex shedding can exist in the bend. The modal stability of two- and three-dimensional perturbations was investigated. Critical Reynolds number of the two-dimensional disturbances was found as extrapolation by lower Reynolds number results. It is much greater than three-dimensional one, but the two-dimensional flow could subcritically unstable with respect to the imposed small-amplitude white noise. For three-dimensional perturbations, the dependence of the critical Reynolds numbers on the bending radius is obtained. For a case of a moderate bending radius the neutral curve is provided and eigenfunctions are studied in detail: three-dimensional instability can be caused by periodic or monotonically growing mode, these unstable modes regard to the recirculation bubbles that occur after the bend.
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- 2021
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27. On Separation between the Degree of a Boolean Function and the Block Sensitivity
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Proskurin, Nikolay V.
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Computer Science - Computational Complexity - Abstract
In this paper we study the separation between two complexity measures: the degree of a Boolean function as a polynomial over the reals and its block sensitivity. We show that separation between these two measures can be improved from $ d^2(f) \geq bs(f) $, established by Tal, to $ d^2(f) \geq (\sqrt{10} - 2)bs(f) $. As a corollary, we show that separations between some other complexity measures are not tight as well, for instance, we can improve recent sensitivity conjecture result by Huang to $s^4(f) \geq (\sqrt{10} - 2)bs(f)$. Our techniques are based on paper by Nisan and Szegedy and include more detailed analysis of a symmetrization polynomial. In our next result we show the same type of improvement in the separation between the approximate degree of a Boolean function and its block sensitivity: we show that $deg_{1/3}^2(f) \geq \sqrt{6/101} bs(f)$ and improve the previous result by Nisan and Szegedy $ deg_{1/3}(f) \geq \sqrt{bs(f)/6} $. In addition, we construct an example which shows that gap between constants in the lower bound and in the known upper bound is less than $0.2$. In our last result we study the properties of conjectured fully sensitive function on 10 variables of degree 4, existence of which would lead to improvement of the biggest known gap between these two measures. We prove that there is the only univariate polynomial that can be achieved by symmetrization of this function by using the combination of interpolation and linear programming techniques., Comment: 16 pages in total (12 for article + 4 for references and appendix)
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- 2021
28. Efficacy of alectinib in comparison with lorlatinib in patients with ALK-positive non-small cell lung cancer: pharmacoeconomic study
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A. S. Kolbin, Yu. M. Gomon, M. A. Proskurin, and Yu. E. Balykina
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non-small cell lung cancer ,nsclc ,targeted therapy ,alectinib ,lorlatinib ,pharmacoeconomic analysis ,cost minimization analysis ,Therapeutics. Pharmacology ,RM1-950 ,Economics as a science ,HB71-74 - Abstract
Objective: to evaluate the clinical and economic effectiveness of alectinib in comparison with lorlatinib in adult patients with advanced anaplastic lymphoma kinase (ALK) positive non-small cell lung cancer (NSCLC).Materials and methods. The calculations included the direct costs of the healthcare system: the costs of drug therapy, detecting and relieving adverse events, palliative care. A Markov model consisting of three patient states (“alive without progression”, “alive with progression”, “death”) was constructed, the probabilities of which were obtained from previously conducted clinical studies. Due to the equivalence of strategies regarding overall and non-progressive survival, the cost minimization analysis was applied.Results. The total costs per 1 patient when using lorlatinib were 40.63% higher than for alectinib (12,551,770 and 7,451,522 rubles, respectively). At the same time, the difference was mainly determined by different costs of targeted therapy: in the alectinib group, the cost of drug therapy per 1 patient amounted to 6,646,247 rubles, in lorlatinib group – to 11,922,814 rubles (44% higher).Conclusion. The use of alectinib in the treatment of patients with ALK-positive NSCLC is justified not only from clinical, but also from an economic point of view.
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- 2023
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29. Mathematical modelling of an unstable bent flow using the selective frequency damping method
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Proskurin, Alexander V.
- Subjects
Physics - Fluid Dynamics ,Mathematics - Numerical Analysis - Abstract
The selective frequency damping method was applied to a bent flow. The method was used in an adaptive formulation. The most dangerous frequency was determined by solving an eigenvalue problem. It was found that one of the patterns, steady-state or pulsating, may exist at some relatively high Reynolds numbers. The periodic flow occurs due to the instability of the steady-state flow. This numerical method is easy to use but requires a great deal of time for calculations.
- Published
- 2020
30. Level attraction and exceptional points in a resonant spin-orbit torque system
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Proskurin, Igor and Stamps, Robert L.
- Subjects
Condensed Matter - Mesoscale and Nanoscale Physics - Abstract
Level attraction can appear in driven systems where instead of repulsion two modes coalesce in a region separated by two exceptional points. This behavior was proposed for optomechanical and optomagnonic systems, and recently observed for dissipative cavity magnon-polaritons. We demonstrate that such a regime exists in a spin-orbit torque system where a magnetic oscillator is resonantly coupled to an electron reservoir. An instability mechanism necessary for mode attraction can be provided by applying an electric field. The field excites interband transitions between spin-orbit split bands leading to an instability of the magnetic oscillator. Two exceptional points then appear in the oscillator energy spectrum and the region of instability. We discuss conditions under which this can occur and estimate the electric field strength necessary for reaching the attraction region for a spin-orbit torque oscillator with Rashba coupling. A proposal for experimental detection is made using magnetic susceptibility measurements., Comment: 10 pages, 4 figures, REVTeX4.2 style
- Published
- 2020
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31. Symmetry Approach to Chiral Optomagnonics in Antiferromagnetic Insulators
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Proskurin, Igor and Stamps, Robert L.
- Subjects
Condensed Matter - Mesoscale and Nanoscale Physics - Abstract
We discuss several aspects of chiral optomagnonics in antiferromagnetic insulators by considering common symmetries between the electromagnetic field and spin excitations. This approach allows us to look at optical and magnetic materials from similar perspectives, and discuss useful analogies between them. We show that spin waves in collinear antiferromagnets and the electromagnetic field in vacuum are both invariant under the same eight-dimensional algebra of symmetry transformations. By such analogy, we can extend the concept of optical chirality to antiferromagnetic insulators, and demonstrate that the spin-wave dynamics in these materials in the presence of a spin current is similar to that of the light inside chiral metamaterials. Photo-excitation of magnonic spin currents is also discussed from the symmetry point of view. It is demonstrated that a direct magnonic spin photocurrent can be exited by circularly polarized light, which can be considered as a magnonic analogue of the photogalvanic effect. We also note that the Zitterbewegung process should appear and may play a role in photo-excitation processes., Comment: Book chapter for "Chirality, Magnetism and Magnetoelectricity", 33 pages, 4 figures
- Published
- 2020
32. Perfect absorption of a focused light beam by a single nanoparticle
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Proskurin, Alexey, Bogdanov, Andrey, and Baranov, Denis G.
- Subjects
Physics - Optics ,Condensed Matter - Mesoscale and Nanoscale Physics - Abstract
Absorption of electromagnetic energy by a dissipative material is one of the most fundamental electromagnetic processes that underlies a plethora of applied problems, including sensing and molecular detection, radar detection, wireless power transfer, and photovoltaics. Perfect absorption is a particular regime when all of the incoming electromagnetic energy is absorbed by the system without scattering. Commonly, the incident energy is delivered to the absorbing system by a plane wave, hence perfect absorption of this wave requires an infinitely extended planar structure. Here, we demonstrate theoretically that a confined incident beam carrying a finite amount of electromagnetic energy can be perfectly absorbed by a finite size deep subwavelength scatterer on a substrate. We analytically solve the self-consistent scattering problem in the dipole approximation and find a closed-form expression for the spatial spectrum of the incident field and the required complex polarizability of the particle. All analytical predictions are confirmed with full-wave simulations., Comment: 4 figures
- Published
- 2020
33. ML-Based Cryptographic Keys Quality Assessment for 5G / 6G Networks Privacy and Security.
- Author
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Dmytro Proskurin, Sergiy Gnatyuk, Tetiana Okhrimenko, and Maksim Iavich
- Published
- 2023
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34. Dataset of Cryptographic Algorithms for UAV Image Encryption based on Artificial Neural Networks (short paper).
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Sergiy Gnatyuk, Andrew Okhrimenko, Denys Navrotskyi, Dmytro Proskurin, and Bohdan Horbakha
- Published
- 2023
35. Free Willy: Prune System Calls to Enhance Software Security.
- Author
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Charlie Groh, Sergej Proskurin, and Apostolis Zarras
- Published
- 2023
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36. Predicting Pseudo-Random and Quantum Random Number Sequences using Hybrid Deep Learning Models.
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Dmytro Proskurin, Sergiy Gnatyuk, and Tetiana Okhrimenko
- Published
- 2023
37. Basics of Using Temporal Data in the Design of Project Management Information Systems
- Author
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Kolykhalova, Evgeniya, Podvalny, Semyon, Proskurin, Dmitry, Filipe, Joaquim, Editorial Board Member, Ghosh, Ashish, Editorial Board Member, Prates, Raquel Oliveira, Editorial Board Member, Zhou, Lizhu, Editorial Board Member, Taratukhin, Victor, editor, Levchenko, Artem, editor, and Kupriyanov, Yury, editor
- Published
- 2023
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38. Advanced Method for Compressing Digital Images as a Part of Video Stream to Pre-processing of UAV Data Before Encryption
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Hu, Zhengbing, Ryabyy, Myroslav, Prystavka, Pylyp, Gnatyuk, Sergiy, Janisz, Karina, Proskurin, Dmytro, Xhafa, Fatos, Series Editor, Hu, Zhengbing, editor, Dychka, Ivan, editor, and He, Matthew, editor
- Published
- 2023
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39. Energy Efficiency of an Orthogonal Balanced Wind Turbine Blade
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Prokopiev, Valery, Proskurin, Andrey, Kacprzyk, Janusz, Series Editor, Gomide, Fernando, Advisory Editor, Kaynak, Okyay, Advisory Editor, Liu, Derong, Advisory Editor, Pedrycz, Witold, Advisory Editor, Polycarpou, Marios M., Advisory Editor, Rudas, Imre J., Advisory Editor, Wang, Jun, Advisory Editor, and Guda, Alexander, editor
- Published
- 2023
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40. Justification and static calculation of the adaptive moving counterweight of a single-bucket excavator
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Vladimir Rashkivskyi and Oleksyi Proskurin
- Subjects
adaptive moving counterweight ,stability ,holding moment ,overturning moment ,Technological innovations. Automation ,HD45-45.2 ,Mechanical industries ,HD9680-9714 ,Instruments and machines ,QA71-90 ,Descriptive and experimental mechanics ,QC120-168.85 ,Information technology ,T58.5-58.64 ,Materials of engineering and construction. Mechanics of materials ,TA401-492 ,Mining engineering. Metallurgy ,TN1-997 ,Earthwork. Foundations ,TA715-787 - Abstract
The results of an analytical study of the effect of loads on the equipment of a single-bucket excavator are presented, and an analysis of previous studies is performed. The work highlights that the work process of a universal single-bucket excavator is a cycle of performing operations - digging and transporting soil. Universal excavators can perform work above and below the level of their parking lot with the working equipment of forward and reverse shovels or with the help of additional interchangeable equipment. During the work process, static and dynamic loads occur on the machine and mechanisms, which affect the stability of the machine and safety on the work site. To increase the stability of single-bucket universal excavators when working on an inclined plane and increase the efficiency of the machine in quarries, construction sites, when disassembling rubble after man-made disasters, accidents, and military operations, it is necessary to create a balancing mechanism of automatic action. The calculation of the stability of a universal single-bucket excavator with an adaptive movable counterweight with working equipment forward and reverse shovel in the basic calculation positions, which are performed when calculating universal single-bucket excavators, has been developed. For an excavator equipped with a reverse shovel, the calculation is made for two positions. Calculation of the stability of an excavator with straight shovel equipment, performed for four positions. Due to the adaptive movable counterweight, an additional, adjustable, arm appears, which automatically balances the system when necessary. Thanks to the automatic system, the single-bucket excavator can work and move on a more inclined plane, the moving counterweight will balance the machine itself, and it is also possible to increase the holding moment and prevent the excavator from tipping over. The expediency of using an adaptive moving counterweight for single-bucket excavators is described. Examples of the use of a movable counterweight in other machines are given. The analysis of related studies was performed and the expediency of using an adaptive moving counterweight in them was substantiated. Preliminary studies in the development of a movable counterweight for single-bucket excavators are provided. The calculation of the stability of a single-bucket excavator with an adaptive movable counterweight in the main design positions has been developed.
- Published
- 2023
- Full Text
- View/download PDF
41. A numerical approach for transient magnetohydrodynamic flows
- Author
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Proskurin, Alexander V. and Sagalakov, Anatoly M.
- Subjects
Physics - Fluid Dynamics - Abstract
In the article the authors present a numerical method for modelling a laminar-turbulent transition in magnetohydrodynamic flows. The equations in the small magnetic Reynolds numbers approach is considered. Speed, pressure and electrical potential are decomposed to the sum of the state values and the finite amplitude perturbations. A solver based on the Nectar++ framework is described. The authors suggest to use of small-length local disturbances as a transition trigger. They can be imposed by blowing or electrical enforcing. The stability of the Hartmann flow and the flow in the bend are considered as examples.
- Published
- 2019
42. Tensile deformations of the magnetic chiral soliton lattice probed by Lorentz transmission electron microscopy
- Author
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Paterson, G. W., Tereshchenko, A. A., Nakayama, S., Kousaka, Y., Kishine, J., McVitie, S., Ovchinnikov, A. S., Proskurin, I., and Togawa, Y.
- Subjects
Condensed Matter - Materials Science - Abstract
We consider the case of a chiral soliton lattice subjected to uniaxial elastic strain applied perpendicular to the chiral axis and derive through analytical modelling the phase diagram of magnetic states supported in the presence of an external magnetic field. The strain induced anisotropies give rise to three distinct non-trivial spin textures, depending on the nature of the strain, and we show how these states may be identified by their signatures in Lorentz transmission electron microscopy (TEM). Experimental TEM measurements of the Fresnel contrast in a strained sample of the prototypical monoaxial chrial helimagnet CrNb$_3$S$_6$ are reported and compare well with the modelled contrast. Our results demonstrate an additional degree of freedom that may be used to tailor the magnetic properties of helimagnets for fundamental research and applications in the areas of spintronics and the emerging field of strain manipulated spintronics., Comment: 13 pages, 6 figures. Minor style and reference edits
- Published
- 2019
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43. Nano-scale tunable optical binding mediated by hyperbolic metamaterials
- Author
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Kostina, N. A., Kislov, D. A., Ivinskaya, A. N., Proskurin, A., Redka, D. N., Novitsky, A., Ginzburg, P., and Shalin, A. S.
- Subjects
Physics - Optics - Abstract
Carefully designed nanostructures can inspire new type of optomechanical interactions and allow surpassing limitations set by classical diffractive optical elements. Apart from strong near-field localization, nanostructured environment allows controlling scattering channels and might tailor many-body interactions. Here we investigate an effect of optical binding, where several particles demonstrate a collective mechanical behaviour of bunching together in a light field. In contrary to classical binding, where separation distances between particles are diffraction limited, an auxiliary hyperbolic metasurface is shown here to break this barrier by introducing several controllable near-field interaction channels. Strong material dispersion of the hyperbolic metamaterial along with high spatial confinement of optical modes, which it supports, allow achieving superior tuning capabilities and efficient control over binding distances on the nanoscale. In addition, a careful choice of the metamaterial slabs thickness enables decreasing optical binding distances by orders of magnitude compared to free space scenarios due to the multiple reflections of volumetric modes from the substrate. Auxiliary tunable metamaterials, which allow controlling collective optomechanical interactions on the nanoscale, open a venue for new investigations including collective nanofluidic interactions, triggered bio-chemical reactions and many others., Comment: 18 pages, 8 figures
- Published
- 2019
44. Fock representations of multicomponent (particularly non-Abelian anyon) commutation relations
- Author
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Daletskii, Alexei, Kalyuzhny, Alexander, Lytvynov, Eugene, and Proskurin, Daniil
- Subjects
Mathematical Physics ,Mathematics - Operator Algebras ,47L90, 81R10 - Abstract
Let $H$ be a separable Hilbert space and $T$ be a self-adjoint bounded linear operator on $H^{\otimes 2}$ with norm $\le1$, satisfying the Yang--Baxter equation. Bo\.zejko and Speicher (1994) proved that the operator $T$ determines a $T$-deformed Fock space $\mathcal F(H)=\bigoplus_{n=0}^\infty\mathcal F_n(H)$. We start with reviewing and extending the known results about the structure of the $n$-particle spaces $\mathcal F_n(H)$ and the commutation relations satisfied by the corresponding creation and annihilation operators acting on $\mathcal F(H)$. We then choose $H=L^2(X\to V)$, the $L^2$-space of $V$-valued functions on $X$. Here $X:=\mathbb R^d$ and $V:=\mathbb C^m$ with $m\ge2$. Furthermore, we assume that the operator $T$ acting on $H^{\otimes 2}=L^2(X^2\to V^{\otimes 2})$ is given by $(Tf^{(2)})(x,y)=C_{x,y}f^{(2)}(y,x)$. Here, for a.a.\ $(x,y)\in X^2$, $C_{x,y}$ is a linear operator on $V^{\otimes 2}$ with norm $\le1$ that satisfies $C_{x,y}^*=C_{y,x}$ and the spectral quantum Yang--Baxter equation. The corresponding creation and annihilation operators describe a multicomponent quantum system. A special choice of the operator-valued function $C_{xy}$ in the case $d=2$ determines non-Abelian anyons (also called plektons). For a multicomponent system, we describe its $T$-deformed Fock space and the available commutation relations satisfied by the corresponding creation and annihilation operators. Finally, we consider several examples of multicomponent quantum systems.
- Published
- 2019
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- View/download PDF
45. Microscopic origin of level attraction for a coupled magnon-photon system in a microwave cavity
- Author
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Proskurin, Igor, Macêdo, Rair, and Stamps, Robert L.
- Subjects
Condensed Matter - Mesoscale and Nanoscale Physics - Abstract
We discuss various microscopic mechanisms for level attraction in a hybridized magnon-photon system of a ferromagnet in a microwave cavity. The discussion is based upon the electromagnetic theory of continuous media where the effects of the internal magnetization dynamics of the ferromagnet are described using dynamical response functions. This approach is in agreement with quantized multi-oscillator models of coupled photon-magnon dynamics. We demonstrate that to provide the attractive interaction between the modes, the effective response functions should be diamagnetic. Magneto-optical coupling is found to be one mechanism for the effective diamagnetic response, which is proportional to photon number. A dual mechanism based on the Aharonov-Casher effect is also highlighted, which is instead dependent on magnon number., Comment: New Journal of Physics, Focus on Cavity Optomagnonics Issue
- Published
- 2019
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- View/download PDF
46. Selection Rules for Optical Vortex Absorption by Landau-quantized Electrons
- Author
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Takahashi, Hirohisa T., Proskurin, Igor, and Kishine, Jun-ichiro
- Subjects
Condensed Matter - Mesoscale and Nanoscale Physics ,Physics - Optics - Abstract
An optical vortex beam carries orbital angular momentum $\ell$ in addition to spin angular momentum $\sigma$. We demonstrate that a Landau-quantized two dimensional electron system absorbs the optical vortex beam through modified selection rules, reflecting two kinds of angular momenta. The lowest Landau level electron absorbs the optical vortex beams with $\sigma=1$ (positive helicity) and $\ell=0$ or $\sigma=-1$ (negative helicity) and $\ell=2$ in the electric dipole transition. The induced electric currents survive only along the edge of the sample, due to cancellation of the bulk currents. Thus, the magnetization can be induced by only the edge current. It is shown that the induced orbital magnetization disappears when the dark ring of the beam coincides with the disk edge. This scheme may provide a helicity-dependent absorption using the optical vortex beam., Comment: 24 pages, 5 figures; submitted to J. Phys. Soc. Jpn.; using jpsj3.cls; Some errors were corrected
- Published
- 2019
47. Theory of standing spin waves in finite-size chiral spin soliton lattice
- Author
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Kishine, J., Sinitsyn, Vl. E., Bostrem, I. G., Proskurin, Igor, Goncalves, F. J. T., Togawa, Y., and Ovchinnikov, A. S.
- Subjects
Condensed Matter - Materials Science - Abstract
We present a theory of standing spin wave (SSW) in a monoaxial chiral helimagnet. Motivated by experimental findings on the magnetic field-dependence of the resonance frequency in thin films of Cr${}$Nb$_{3} $S${}_{6}$[Goncalves et al., Phys. Rev. B95, 104415 (2017)], we examine the SSW over a chiral soliton lattice (CSL) excited by an ac magnetic field applied parallel and perpendicular to the chiral axis. For this purpose, we generalize Kittel-Pincus theories of the SSW in ferromagnetic thin films to the case of non-collinear helimagnet with the surface end spins which are softly pinned by an anisotropy field. Consequently, we found there appear two types of modes. One is a Pincus mode which is composed of a long-period Bloch wave and a short-period ripple originated from the periodic structure of the CSL. Another is a short-period Kittel ripple excited by space-periodic perturbation which exists only in the case where the ac field is applied perpendicular the chiral axis. We demonstrate that the existence of the Pincus mode and the Kittel ripple is consistent with experimentally found double resonance profile., Comment: 17 pages, 14 figures
- Published
- 2019
- Full Text
- View/download PDF
48. ADAPTIVE ILLUMINATION CORRECTION ALGORITHM BASED ON RETINEX TECHNOLOGY FOR CAMERA TRAP IMAGES
- Author
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A. G. Zotin and A. V. Proskurin
- Subjects
Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Applied optics. Photonics ,TA1501-1820 - Abstract
Camera traps generating a huge number of images help to study and monitor the wildlife. However, camera traps work at any time of the day and under any weather conditions. Therefore, many images have low or high illumination, blurring, and other defects. This complicates image analysis by both humans and computer systems. In this study, we develop an adaptive illumination correction algorithm based on a modified Multi-Scale Retinex (MSR). First, we accelerate computation by using recursive implementation of the Gaussian filter and utilizing look-up tables to find logarithms and new brightness values. Second, response of the MSR function is transformed by a modified threshold normalization to improve image quality. The upper and lower thresholds are calculated based on statistical information. Finally, we offer automatic adjustment of parameters depending on the area of the image in order to increase usability. Proposed algorithm was tested with various settings on a set of images obtained from camera traps. Experimental results show a high potential for its application.
- Published
- 2023
- Full Text
- View/download PDF
49. ACC neural ensemble dynamics are structured by strategy prevalence
- Author
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Mikhail Proskurin, Maxim Manakov, and Alla Karpova
- Subjects
cingulate ,decision-making ,population dynamics ,Medicine ,Science ,Biology (General) ,QH301-705.5 - Abstract
Medial frontal cortical areas are thought to play a critical role in the brain’s ability to flexibly deploy strategies that are effective in complex settings, yet the underlying circuit computations remain unclear. Here, by examining neural ensemble activity in male rats that sample different strategies in a self-guided search for latent task structure, we observe robust tracking during strategy execution of a summary statistic for that strategy in recent behavioral history by the anterior cingulate cortex (ACC), especially by an area homologous to primate area 32D. Using the simplest summary statistic – strategy prevalence in the last 20 choices – we find that its encoding in the ACC during strategy execution is wide-scale, independent of reward delivery, and persists through a substantial ensemble reorganization that accompanies changes in global context. We further demonstrate that the tracking of reward by the ACC ensemble is also strategy-specific, but that reward prevalence is insufficient to explain the observed activity modulation during strategy execution. Our findings argue that ACC ensemble dynamics is structured by a summary statistic of recent behavioral choices, raising the possibility that ACC plays a role in estimating – through statistical learning – which actions promote the occurrence of events in the environment.
- Published
- 2023
- Full Text
- View/download PDF
50. The evolution of non-linear disturbances in magnetohydrodynamic flows
- Author
-
Proskurin, Alexander and Sagalakov, Anatoly
- Subjects
Physics - Fluid Dynamics - Abstract
In this article the stability loss of the Hartmann flow are investigated by applying the equations for disturbances. The velocity and electric potential quasi-static MHD model is used. The equations allow us to calculate time-dependent disturbance fields using a base flow and an initial disturbance. Two type of initial perturbations are considered: the eigenfunction of the linearized MHD equations and a fluid injection into the flow. These two approaches lead to identical stability results. However, we found a significant difference in the practical implementation of the two approaches. Dealing with the eigenproblem of the linearized MHD system is a laborious task. In terms of calculation costs it is equal to a series of nonlinear perturbation simulations, and if the Hartmann number is increased, the proportion becomes worse. The non-linear stability analysis produced by these two methods shows that the injection technique can also be used in numerical analysis, and that this method is less expensive in terms of calculation costs.
- Published
- 2019
- Full Text
- View/download PDF
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