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Merging bound states in the continuum in an open acoustic resonator

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science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 124-131页

作者： Lujun Huang Bin Jia Artem s.Pilipchuk sibo Huang Chen shen Almas F.sadreev Yong Li Andrey E.miroshnichenko school of Physics and Electronic sciences East China Normal University Institute of Acoustics Tongji University L.V.Kirensky Institute of Physics Department of Mechanical Engineering Rowan University school of Engineering and Technology University of New South Wales at Canberra

Bound states in the continuum （BICs） are perfectly localized resonances despite embedding in the continuum ***,an isolated BIC is very sensitive to the structure ***,we report merging acoustic BICs in a single open resonator,robust against the structure *** find that both symmetry-protected BIC and Friedrich-Wintgen BIC are sustained in a single coupled waveguide-resonator *** varying the height and length of the resonator,these two BICs move toward each other and merge into a single one at a critical *** to an individual BIC,the merged BIC is robust against fabrication error because its Q-factor is proportional to ΔL-4,whereΔL embodies the structure *** essence of this extraordinary phenomenon is perfectly explained by the two-and three-level approximations of the effective nonHermitian ***,we present direct experimental demonstrations of the moving and merging of BICs in a coupled 3D waveguide-resonator,which are evidenced by the vanishing of the linewidth of Fano resonance in the transmission *** results may find exciting applications in designing high-quality acoustic sources,sensors and filters.

关键词： acoustic resonances bound state in the continuum high-Q resonances

Control of light scattering by nanoparticles with optically-induced magnetic responses

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Chinese Physics B 2014年第4期23卷 41-51页

作者：刘伟 Andrey E. miroshnichenko Yuri s. Kivshar College of Optoelectronic science and Engineering National University of Defence Technology Nonlinear Physics Center and Center for Ultrahigh-bandwidth Devices for Optical systems CUDOs) Research School of Physics and EngineeringAustralian National University

Conventional approaches to control and shape the scattering pattems of light generated by different nanostructures are mostly based on engineering of their electric response due to the fact that most metallic nanostructures support only electric resonances in the optical frequency range. Recently, fuelled by the fast development in the fields of metamaterials and plasmonics, artificial optically-induced magnetic responses have been demonstrated for various nanostructures. This kind of response can be employed to provide an extra degree of freedom for the efficient control and shaping of the scattering patterns of nanoparticles and nanoantennas. Here we review the recent progress in this research direction of nanoparticle scattering shaping and control through the interference of both electric and optically-induced magnetic responses. We discuss the magnetic resonances supported by various structures in different spectral regimes, and then summarize the original results on the scattering shaping involving both electric and magnetic responses, based on the interference of both spectrally separated （with different resonant wavelengths） and overlapped dipoles （with the same resonant wavelength）, and also other higher-order modes. Finally, we discuss the scattering control utilizing Fano resonances associated with the magnetic responses.

关键词： optically-induced magnetic response scattering control Mie resonance Fano resonance

Characteristics of shallow gas hydrate in Okhotsk sea

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science China Earth sciences 2008年第3期51卷 415-421页

作者： anatoly OBZHIROV V.I. Il’ichev Pacific Oceanological Institute of the Far Eastern Branch of Russian Academy of sciences

Multidisciplinary field investigations were carried out in Okhotsk sea by R/V Akademik M.A. Lavrentyev (LV) of the Russian Academy of sciences (RAs) in May 2006, supported by funding agencies from Ko- rea, Russia, Japan and China. Geophysical data including echo-sounder, bottom profile, side-scan- sonar, and gravity core sample were obtained aimed to understand the characteristics and formation mechanism of shallow gas hydrates. Based on the geophysical data, we found that the methane flare detected by echo-sounder was the evidence of free gas in the sediment, while the dome structure de- tected by side-scan sonar and bottom profile was the root of gas venting. Gas hydrate retrieved from core on top of the dome structure which was interbedded as thin lamination or lenses with thickness varying from a few millimeters to 3 cm. Gas hydrate content in hydrate-bearing intervals visually amounted to 5%―30% of the sediment volume. This paper argued that gases in the sediment core were not all from gas hydrate decomposition during the gravity core lifting process, free gases must existed in the gas hydrate stability zone, and tectonic structure like dome structure in this paper was free gas central, gas hydrate formed only when gases over-saturated in this gas central, away from these struc- tures, gas hydrate could not form due to low gas concentration.

关键词： Okhotsk sea shallow gas hydrates free gas dome structure

sINGULAR sPECTRUM ANALYsIs:METHODOLOGY AND APPLICATION TO ECONOMICs DATA

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Journal of systems science & Complexity 2009年第3期22卷 372-394页

作者： Hossein HAssANI anatoly ZHIGLJAVsKY Institute for Trade studies and Research (ITsR) Centre for Optimisation and Its Applications School of Mathematics Centre for Optimization and Its Applications School of Mathematics

This paper describes the methodology of singular spectrum analysis (ssA) and demonstratethat it is a powerful method of time series analysis and forecasting,particulary for economic time *** authors consider the application of ssA to the analysis and forecasting of the Iranian nationalaccounts data as provided by the Central Bank of the Islamic Republic of Iran.

关键词： Economic time series forecasting Iranian national accounts ssA.

Thermal radiation and natural convection in a large-scale enclosure heated from below:Building application

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Building simulation 2021年第3期14卷 681-691页

作者： stepan A.Mikhailenko Igor V.miroshnichenko Mikhail A.sheremet Laboratory on Convective Heat and Mass Transfer Tomsk State University634050 TomskRussia Regional scientific and Educational Mathematical Centre Tomsk State University634050 TomskRussia

A computational research of radiative-convective energy transport in large-scale enclosure with a heat-generating heater under normal room conditions has been *** heater(underfloor heating system)is located at the bottom of the *** the Boussinesq assumption,the control equations have been solved contemporaneously to receive both the velocity fields and temperature *** generate the systems of linear equations using vorticity and stream function,the finite difference technique has been *** developed convective-radiative model has been validated through a comparison with several *** influence of heater size and location,internal surfaces emissivity from 0 to 1,Ostrogradsky number for a wide range from 0 to 5 on Nusselt numbers and both stream function and temperature distributions has been *** results demonstrate that the influence of the thermal radiation on total heat transfer increases with surface emissivity of walls and heater surfaces.

关键词： indoor environment natural convection thermal radiation large-scale cabinet local heater finite difference method

Cohomology of bundles on homological Hopf manifolds

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science China Mathematics 2009年第12期52卷 2688-2698页

作者： LIBGOBER anatoly Department of Mathematics University of IllinoisChicagoIL 60607USA

We discuss the properties of complex manifolds having rational homology of s 1 × s 2n?1 including those constructed by Hopf, Kodaira and Brieskorn-van de Ven. We extend certain previously known properties of cohomology of bundles on such manifolds. As an application we consider degeneration of Hodge-de Rham spectral sequence in this non Kahler setting.

关键词： Hopf manifolds cohomology of vector bundles local systems universal covers stein spaces 32J27 32Q55 32M17 32s25 32Q28

short-term reliability evaluation for power stations by using Lz-transform

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Journal of Modern Power systems and Clean Energy 2013年第2期1卷 110-117页

作者： anatoly LIsNIANsKI Hanoch BENHAIM Reliability Department The Israel Electric Corporation1 Nativ HaOr StreetP.O.B.10HaifaIsrael

A short-term reliability evaluation is used for power stations,where each power generating unit is presented by a multi-state Markov *** main obstacle for reliability evaluation in such a case is a“curse of dimensionality”—a great(huge)number of states of entire power station that should be analyzed.A modern approach is proposed based on using Lz-transform that drastically simplifies *** proposed approach is useful for power system security analysis and short-term operating *** order to illustrate the proposed approach,the short-term reliability evaluation for a power station with different coal fired generating units is presented.

关键词： Power system Generating unit Generating capacity Multi-state Markov model Lz-transform Universal generating function

Paleoproterozoic Underwater Volcanism and Microfossil-Like structures in the Metasedimentary siliceous Rocks,Hogland Island,Russia

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Journal of Earth science 2018年第6期29卷 1431-1442页

作者： anatoly M.Belyaev Institute of Earth sciences St.Petersburg State University

Geological surveys showed that rhyolite and basalt strata with pillow structures typical for underwater volcanism form sheets over the svecofennian basement. Original geochemical and isotope-geochemical data confirmed that the rhyolites were formed contemporaneously with the rapakivi granites of the Wiborg Massif（1 640 Ma）, and the basalts are similar to gabbro-anorthosites. Abnormally high content of K2O and relatively low content of Na2O in rhyolites and basalts are interpreted as a result of hydrothermal interaction of eruptive magmas with K-enriched hot seawater. The strata of siliceous metasedimentary rocks（microquartzites） within basaltic and rhyolitic lavas were formed in processes of chemogenic sedimentation and subsequent contact metamorphism during underwater volcanism. Microquartzites showed carbon vastly depleted of heavy isotope 13С. This is typical for rocks formed with participation of living substance. The Raman spectra of the remaining carbon-containing substance have graphite bands. In the microquartzites among basalts and rhyolites we found a community of structures with external and internal morphology similar to modern or fossilized marine microorganisms： spiral cyanobacterias, amoebas, diatoms, foraminifers, virus capsids, flagellates and multicellular organisms. It is assumed that these silificated and ferruginizated microfossils represent the Paleoproterozoic community of marine microorganisms.

关键词： submarine volcanism siliceous rocks silification Paleoproterozoic microfossils carbon isotopes

High damping in Fe-Ga-La alloys:Phenomenological model for magneto-mechanical hysteresis damping and experiment

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Journal of Materials science & Technology 2021年第13期72卷 69-80页

作者： Meng sun anatoly Balagurov Ivan Bobrikov Xianping Wang Wen Wen Igor s.Golovin Qianfeng Fang Key Laboratory of Materials Physics Institute of Solid State PhysicsHFIPSChinese Academy of SciencesHefei 230031China Department of Materials science and Engineering University of Science and Technology of ChinaHefei 230026China Frank Laboratory of Neutron Physics Joint Institute for Nuclear ResearchDubnaRussia Lomonosov Moscow state University MoscowRussia shanghai Advanced Research Institute Chinese Academy of SciencesShanghai 201204China National University of science and Technology“MIsIs” MoscowRussia

Ferromagnetic high damping(FHA)alloys with a wide temperature range from-150℃to 300℃have unique application value in extreme *** the present work,the damping behaviors of Fe-21 Ga-xLa(x=0.12 wt.%,0.24 wt.%,0.47 wt.%,1.18 wt.%,and 2.33 wt.%La)alloys have been studied in detail,and a new phenomenological model has been *** the increase of La content,the Laves phase(LaGa_(2))in the matrix increases gradually,and the resistance opposing the domain movement increases as *** with the results of synchrotron radiation X-ray diffraction,neutron diffraction,and magnetic domain observation,the resistance mainly comes from three parts:the average stress related to the lattice distortion of the matrix,the average stress related to the increasing area energy of domain walls(DWs),and the ave rage stress related to the increasing demagnetization energy induced by the Laves *** from the traditional method of reducing internal stress through annealing to improve the damping capacity,the proper internal stress barriers are necessary to Barkhausen jumps to dissipate ***,proper doping to balance resistance and mobility of DWs is a reliable way to improve damping ***,for Fe-Al and Fe-Cr based Alloys,the new model also has a good fitting *** study provides a theoretical and experimental reference for improving the functional properties of ferromagnetic alloys.

关键词： Magneto-mechanical hysteresis damping Laves phase(LaGa_(2)) Internal stress distribution Neutron-diffraction patterns Domain walls