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Intelligent metaphotonics empowered by machine learning

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Opto-Electronic Advances 2022年第3期5卷 1-24页

作者： Sergey Krasikov Aaron Tranter andrey bogdanov Yuri Kivshar Nonlinear Physics Center Research School of PhysicsThe Australian National UniversityCanberra ACT 2601Australia School of Physics and Engineering ITMO UniversitySt.Petersburg 197101Russia Centre for Quantum Computation and Communication Technology Department of Quantum ScienceResearch School of PhysicsThe Australian National UniversityCanberraACT 2601Australia

In the recent years,a dramatic boost of the research is observed at the junction of photonics,machine learning and artifi-cial intelligence.A new methodology can be applied to the description of a variety of photonic systems including optical waveguides,nanoantennas,and *** novel approaches underpin the fundamental principles of light-matter interaction developed for a smart design of intelligent photonic *** intelligence and machine learn-ing penetrate rapidly into the fundamental physics of light,and they provide effective tools for the study of the field of metaphotonics driven by optically induced electric and magnetic *** we overview the evaluation of meta-photonics induced by artificial intelligence and present a summary of the concepts of machine learning with some specif-ic examples developed and demonstrated for metasystems and metasurfaces.

关键词： metaphotonics machine learning artificial intelligence

Meta-optics and bound states in the continuum

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Science Bulletin 2019年第12期64卷 836-842页

作者： Kirill Koshelev andrey bogdanov Yuri Kivshar Nonlinear Physics Centre Australian National UniversityCanberra ACT 2601Australia ITMO University St. Petersburg 197101Russia

We discuss the recent advances in meta-optics and nanophotonics associated with the physics of bound states in the continuum(BICs). Such resonant states appear due to a strong coupling between leaky modes in optical guiding structures being supported by subwavelength high-index dielectric Mieresonant nanoantennas or all-dielectric metasurfaces. First, we review briefly very recent developments in the BIC physics in application to isolated subwavelength particles. We pay a special attention to novel opportunities for nonlinear nanophotonics due to the large field enhancement inside the particle volume creating the resonant states with high-quality(high-Q) factors, the so-called quasi-BIC, that can be supported by the subwavelength particles. Second, we discuss novel applications of the BIC physics to alldielectric optical metasurfaces with broken-symmetry meta-atoms when tuning to the BIC conditions allows to enhance substantially the Q factor of the flat-optics dielectric structures. We also present the original results on nonlinear high-Q metasurfaces and predict that the frequency conversion efficiency can be boosted dramatically by smart engineering of the asymmetry parameter of dielectric metasurfaces in the vicinity of the quasi-BIC regime.

关键词： Bound states in the continuum Meta-optics Second-harmonic generation Nanoresonator Metasurfaces

Bound states in the continuum and Fano resonances in the strong mode coupling regime

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Advanced Photonics 2019年第1期1卷 33-44页

作者： andrey A.bogdanov Kirill LKoshelev Polina VKapitanova Mikhail VRybin Sergey AGladyshev Zarina FSadrieva Kirill BSamusev Yuri SKivshar a Mikhail FLimonov ITMO University Department of Nanophotonics and MetamaterialsSt.PetersburgRussia Ioffe Institute St.PetersburgRussia Australian National University Nonlinear Physics CenterCanberraAustralia

The study of resonant dielectric nanostructures with a high refractive index is a new research direction in the nanoscale optics and metamaterial-inspired *** of the unique optically induced electric and magnetic Mie resonances,high-index nanoscale structures are expected to complement or even replace different plasmonic components in a range of potential *** study a strong coupling between modes of a single subwavelength high-index dielectric resonator and analyze the mode transformation and Fano resonances when the resonator’s aspect ratio *** demonstrate that strong mode coupling results in resonances with high-quality factors,which are related to the physics of bound states in the continuum when the radiative losses are almost suppressed due to the Friedrich–Wintgen scenario of destructive *** explain the physics of these states in terms of multipole decomposition,and show that their appearance is accompanied by a drastic change in the far-field radiation *** reveal a fundamental link between the formation of the high-quality resonances and peculiarities of the Fano parameter in the scattering cross-section *** theoretical findings are confirmed by microwave experiments for the scattering of high-index cylindrical resonators with a tunable aspect *** proposed mechanism of the strong mode coupling in single subwavelength high-index resonators accompanied by resonances with high-quality factors helps to extend substantially functionalities of all-dielectric nanophotonics,which opens horizons for active and passive nanoscale metadevices.

关键词： Fano resonance bound states in the continuum Mie resonance dielectric resonator meta-optics

On Differential Equations of Integrable Billiard Tables

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Acta Mathematica Sinica,English Series 2024年第1期40卷 417-424页

作者： Vladimir DRAGOVIC andrey E.MIRONOV Department of Mathematical Sciences The University of Texas at DallasRichardson TXUSA Mathematical Institute SANU BelgradeSerbia Novosibirsk State University NovosibirskRussia Sobolev Institute of Mathematics of the Siberian Branch of the Russian Academy of Sciences NovosibirskRussia

We introduce a method to find differential equations for functions which define tables,such that associated billiard systems admit a local first *** illustrate this method in three situations:the case of(locally)integrable wire billiards,for finding surfaces in R^(3)with a first integral of degree one in velocities,and for finding a piece-wise smooth surface in R^(3)homeomorphic to a torus,being a table of a billiard admitting two additional first integrals.

关键词： Polynomial first integrals wire billiards piece-wise smooth surfaces

Modeling of Leachate Propagation in a Municipal Solid Waste Landfill Foundation

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Fluid Dynamics & Materials Processing 2024年第6期20卷 1407-1424页

作者： Nadezhda Zubova andrey Ivantsov Institute of Continuous Media Mechanics of the Ural Branch Russian Academy of SciencePerm614013Russia

The study deals with the numerical modeling of leachate distribution in the porous medium located under a municipal solid waste disposal landfill(MSWLF).The considered three-layer system is based on geological data obtained from field *** simplicity,the problem is investigated by assuming a two-component ***,the heat produced by landfills due to biological and chemical processes and the thermal diffusion mechanism contributing to pollution transport are taken into *** numerical modeling of the propagation of leachate in the considered layered porous medium is implemented for parameters corresponding to natural soil and for the case where disruption of the porous medium structure is due to cracks formation or *** latter is accompanied by an increase in rock *** this case,the emergence of multi-vortex flow in the layer of high permeability is observed to substantially influence the bottom layers and cause intensification of the leachate *** effects should be taken into account when estimating the parameters and properties of materials required for the construction of solid waste disposal facilities.

关键词： Three-layer porous medium binary mixture diffusion thermal diffusion

Comparison of extraction abilities of deep eutectic solvents and aqueous acid solutions for extraction of rare earths and transition metals

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Journal of Rare Earths 2024年第6期42卷 1157-1164,I0006页

作者： Svetlana Drogobuzhskaya Margarita Frolova andrey Shishov Nikita Tsvetov Tananaev Institute of Chemistry-Subdivision of the Federal Research Centre《Kola Science Centre of the Russian Academy of Sciences》 18420926a AcademgorodokApatityRussia Murmansk State Technical University 183010Sportivnaja str.13MurmanskRussia Department of Analytical Chemistry Institute of ChemistrySaint Petersburg State UniversitySpbSU.1990347/9 Universitetskaya embSt.Petersburg Russia

In recent years,deep eutectic solvents have attracted increasing interest as effective extractants for the separation of both organic substances and metals from various ***-based deep eutectic solvents are most often used as extractants for the extraction of *** this work,for the first time,the extraction efficiency of transition metals and rare earth elements(Y,Zr,Nb,La,Ce,Pr,Nd,Sm,Eu,Gd,Tb,Dy,Ho,Er,Tm,Yb,Lu,Hf and Ta)from mining tailings and Na,K,Ca,Mg,Cu,Fe,Mn,Pb,Ba,Ni and Sr from biodiesel samples using acidic deep eutectic solvents and saturated aqueous solutions of the same acids(malonic,malic,tartaric and citric)is *** this,deep eutectic solvents based on acids and their aqueous saturated solutions were prepared and *** prepared mixtures were analyzed by IR spectroscopy to confirm the formation of eutectic *** such as the density and viscosity of the resulting mixtures were also investigated,as this can be of key importance for the efficiency of metal *** extraction of rare earth metals from mining tailings took a long time(up to several days),while the extraction of metals from fuel took no more than 30 *** emission spectral methods were used as an analysis *** is shown that the extraction efficiency with aqueous solutions is better than that with eutectic solvents,which casts doubt on the need for deep eutectic solvents use in this area.

关键词： Deepeutectic solvent Metal separation Elemental analysis Rare earth metals Biodiesel

Consideration of the influence of supports in modeling the electromagnetic fields of 25 kV traction networks under emergency conditions

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Global Energy Interconnection 2024年第4期7卷 528-540页

作者： Konstantin Suslov andrey Kryukov Ekaterina Voronina Pavel Ilyushin Department of Hydropower and Renewable Energy National Research UniversityMoscow Power Engineering InstituteMoscow 11250Russia Department of Power Supply and Electrical Engineering Irkutsk National Research Technical UniversityIrkutsk 664074Russia Department of Transport Electric Power Irkutsk State Transport UniversityIrkutsk 664074Russia Department of Research on the Relationship between Energy and the Economy Energy Research Institute of the Russian Academy of SciencesMoscow 117186Russia

Single-phase 25 kV traction networks of electrified alternating current(AC)railways create electromagnetic fields(EMFs)with significant levels of *** most intense magnetic fields occur when short circuits exist between the contact wire and rails or *** the short duration of exposure,they can adversely affect electronic devices and induce significant voltages in adjacent power lines,which is dangerous for operating *** numerous investigations have focused on modeling the EMF of traction networks and power lines,the challenge of determining the three-dimensional electromagnetic fields near metal supports during the flow of a short-circuit current through them is yet to be *** this case,the field has a complex spatial structure that significantly complicates the calculations of *** study proposes a methodology,algorithms,software,and digital models for determining the EMF in the described emergency *** the modeling process,the objects being studied were represented by segments of thin wires to analyze the distribution of the electric charge and calculate the intensities of the electric and magnetic *** approach was implemented in the Fazonord software,and the modeling results show a substantial increase in EMF levels close to the support,with a noticeable decrease in the levels as the distance from it *** procedure implemented in the commercial software Fazonord is universal and can be used to determine electromagnetic fields at any electrical power facility that includes live parts of limited *** on the proposed procedure,the EMF near the supports of overhead power lines and traction networks of various designs could be determined,the EMF levels at substations can be calculated,and the influence of metal structures located near traction networks,such as pedestrian crossings at railway stations,can be considered.

关键词： Power supply systems AC railways Emergency conditions Electromagnetic fields near supports Modeling Electromagnetic safety

Energy-efficient joint UAV secure communication and 3D trajectory optimization assisted by reconfigurable intelligent surfaces in the presence of eavesdroppers

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Defence Technology（防务技术） 2024年第1期31卷 537-543页

作者： Huang Hailong Mohsen Eskandari andrey V.Savkin Wei Ni The Department of Aeronautical and Aviation Engineering The Hong Kong Polytechnic UniversityHong KongChina School of Electrical Engineering and Telecommunications University of New South WalesSydney2052Australia Data61 CSIROAustralia

We consider a scenario where an unmanned aerial vehicle(UAV),a typical unmanned aerial system(UAS),transmits confidential data to a moving ground target in the presence of multiple *** friendly reconfigurable intelligent surfaces(RISs) help to secure the UAV-target communication and improve the energy efficiency of the *** formulate an optimization problem to minimize the energy consumption of the UAV,subject to the mobility constraint of the UAV and that the achievable secrecy rate at the target is over a given *** present an online planning method following the framework of model predictive control(MPC) to jointly optimize the motion of the UAV and the configurations of the *** effectiveness of the proposed method is validated via computer simulations.

关键词： Unmanned aerial systems(UASs) Unmanned aerial vehicle(UAV) Communication security Eaves-dropping Reconfigurable intelligent surfaces(RIS) Autonomous navigation and placement Path planning Model predictive control

Preface to the Special Issue on Modeling and Data Analysis Methods for the SMILE mission

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Earth and Planetary Physics 2024年第1期8卷 1-4页

作者： TianRan Sun Hyunju Connor andrey Samsonov National Space Science Center Chinese Academy of SciencesBeijing 100190China NASA Goddard Space Flight Center US Mullard Space Science Laboratory University College LondonUK

The SMILE(Solar wind Magnetosphere Ionosphere Link Explorer)project(http://***/smile/,https://***/web/smile/mission)is a joint spacecraft mission of the European Space Agency(ESA)and the Chinese Academy of Sciences(CAS)with an expected launch in *** aims to study the global interactions of solar wind–magnetosphere–ionosphere innovatively by imaging the Earth’s magnetosheath and cusps in soft X-rays and the northern auroral region in ultraviolet(UV)while simultaneously measuring plasma and magnetic field parameters in the solar wind and magnetosheath along a highly-elliptical and highly-inclined *** special issue is composed of 22 articles,presenting recent progress in modeling and data analysis techniques developed for the SMILE *** this preface,we categorize the articles into the following seven topics and provide brief summaries:(1)instrument descriptions of the Soft X-ray Imager(SXI),(2)numerical modeling of the X-ray signals,(3)data processing of the X-ray images,(4)boundary tracing methods from the simulated images,(5)physical phenomena and a mission concept related to the scientific goals of SMILE-SXI,(6)studies of the aurora,and(7)ground-based support for SMILE.

关键词： SMILE X-ray imaging magnetosphere auroral ionosphere