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Simulation of detection and scattering of sound waves by the lateral line of a fish

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Chinese Physics B 2022年第2期31卷 398-404页

作者： v M Adamyan I y Popov I v Blinova v v Zavalniuk Odessa I.I.Mechnikov National University Dvoryanskaya Str.2Odesa65082Ukraine ITMO University Kronverkskiy49Saint Petersburg197101Russia Odessa Military Academy 10 Fontanska RoadOdesa 65009Ukraine

A solvable model of lateral line of a fish based on a wave equation with additional boundary conditions on a set of isolated points is *** the framework of this model it is shown that the ratio of pressures on lateral lines on different fish flanks,as well as the cross section of sound scattering on both the lines,strongly depends on angles of incidence of incoming sound *** strong angular dependence of the pressure ratio seems to be sufficient for the fish to determine the directions from which the sound is coming.

关键词： acoustic equation point self-adjoint perturbations of Laplace operator scattering lateral line

On the l_2-stability of time-varying linear and nonlinear discrete-time MIMO systems

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Control Theory and Technology 2014年第3期12卷 250-274页

作者： y.v.vENKATESH Department of ECE National University of SingaporeSingapore Electrical Sciences Indian Institute of ScienceBangalore India

New conditions are derived for the l2-stability of time-varying linear and nonlinear discrete-time multiple-input multipleoutput （MIMO） systems, having a linear time time-invariant block with the transfer function F（z）, in negative feedback with a matrix of periodic/aperiodic gains A（k）, k = 0,1, 2,... and a vector of certain classes of non-monotone/monotone nonlinearities φp（-）, without restrictions on their slopes and also not requiring path-independence of their line integrals. The stability conditions, which are derived in the frequency domain, have the following features： i） They involve the positive definiteness of the real part （as evaluated on ｜z｜ = 1） of the product of Г （z） and a matrix multiplier function of z. ii） For periodic A（k）, one class of multiplier functions can be chosen so as to impose no constraint on the rate of variations A（k）, but for aperiodic A（k）, which allows a more general multiplier function, constraints are imposed on certain global averages of the generalized eigenvalues of （A（k ＋ 1）,A（k））, k = 1, 2 iii） They are distinct from and less restrictive than recent results in the literature.

关键词： Circle criterion Discrete-time MIMO system l2-stability Feedback system stability Linear matrix inequalities (LMI) Lur'e problem Multiplier functions Nyquist's criterion Periodic coefficient systems Popov's criterion Time-varying systems

Renewable energy based microgrid system sizing and energy management for green buildings

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Journal of Modern Power Systems and Clean Energy 2015年第1期3卷 1-13页

作者： y.v.PAvAN KUMAR Ravikumar BHIMASINGU Department of Electrical Engineering Indian Institute of Technology Hyderabad(IITH)HyderabadIndia

The objective of this paper is to model a hybrid power system for buildings,which is technically feasible and economically *** a view to promote renewable energy sources,photovoltaics and wind turbines are integrated with the grid connected *** system is modeled and the optimal system configuration is estimated with the help of hybrid optimization model for electric renewables(HOMER).The logic is illustrated with a case study based on the practical data of a building located in southern *** building is associated with 3.4 MWh/day priority load(peak load as 422 kW),as well as 3.3 MWh/day deferrable load(peak load as 500 kW).Sensitivity analysis is performed to deal with uncertainties such as the increase in electricity consumption and grid tariff,environmental changes,*** the simulation result,it is observed that the designed system is cost effective and environment friendly,which leads to 6.18%annual cost savings and reduces CO_(2) emissions by 38.3%.Sensitivity results indicate that the system is optimal and adaptable in a certain range of unanticipated variances with respect to best estimated ***,an energy management strategy is developed for the optimal system to ensure reliable power during contingency and *** green and hybrid power system designed can be adaptable to any critical and large consumers of urban buildings.

关键词： Renewable energy sources(RES) Hybrid power systems(HPS) Photovoltaic(Pv) Wind turbine(WT) Low-carbon electricity Energy management Total net present cost(TNPC)

Spectroscopic investigations on yb^3+ doped and Pr^3+/yb^3+ codoped tellurite glasses for photonic applications

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Journal of Rare Earths 2021年第1期39卷 33-42,I0002页

作者： M.Seshadri M.J.v.Bell v.Anjos y.Messaddeq Grupo de Engenharia e Espectroscopia de Materiais Departamento de Fisica-ICEUniversidade Federal de Juiz de ForaJuiz de ForaMG36036-900Brazil Centre d'Optique Photonique et Laser2375 Rue de la TerrasseUniversite LavalQuebecQCG1V 0A6Canada

In this work we repo rt on structural and spect roscopic properties of yb^3+doped and Pr^3+/yb^3+co-doped TeO2-Bi2 O3-ZnO-Li2 O-Nb2 O5(TBZLN)tellurite *** and stretching modes of TeO2 and Te-OH bond(strong and weak)were analysed from the deconvolution of observed Raman and FT-IR *** on the absorption measurements,the energy bands of yb^3+and Pr^3+ions are *** spectroscopic properties for the radiative transitions of yb^3+and Pr^3+ions were reported using McCumber and Judd-Ofelt *** emission bands originating from 3 P1 and 3 P0 to lower lying levels of Pr^3+were registered under 447 nm *** emission band around 1334 nm assigned to the Pr3:1 G4→3 H5 was observed when excited at 980 *** stimulated emission cross-section(σemi(λ))and effective linewidth(Δλeff)for the 3 P1→3 H6,3 P1→3 H5,3 P0→3 H6,3 P0→3 F2,3 P1→3 F3,3 P1→3 F4,3 P0→3 F4 and 1 G4→3 H5 transitions of Pr^3+are *** luminescence in Pr^3+/yb^3+codoped glass upon 980 nm excitation was *** resonant transfer processes between yb^3+and Pr^3+ions are presented and *** chromaticity co-ordinates were also evaluated from the visible emission spectra showing that Pr^3+/yb^3+co-doped glass may be suitable for the development of yellow-orange(λexc=447 nm)and near white light(λexc=980 nm)emitting devices in photonics.

关键词： Rare earth ions Tellurite glass Spectroscopic properties Upconversion luminescence

A third superchron during the Early Paleozoic

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Episodes 2005年第2期28卷 78-84页

作者： v.Pavlov y.Gallet DepartmentoftheMainGeomagnetic.Field InstituteofPhysicsofthe.EarthMoscow：Russia／／LaboratoiredePaléomagnétismeInstitutdePhysiqueduGlobedePansFrance LaboratoiredePaléomagnétisme InstitutdePhysiqueduGlobedePansFrance

Research on geomagnetic reversal chronology has established the existence of two superchrons, one during the Cretaceous and the other (Kiaman) during the Late *** the past few years, we have performed several magnetostratigraphic studies on Early Paleozoic (Cambrian and Ordovician) sedimentary sequences from Siberia. Our results show high magnetic reversal frequencies during the Middle Cambrian. In contrast, several records show the occurrence of a -20 Myr long reversed polarity interval in the Lower and Middle Ordovician, suggesting the presence of a third superchron. We propose to give the name of “Moyero” to this new superchron; this name is attributed to the Siberian section which first yielded a complete record of this reversed polarity interval.

关键词：古生代地磁反演地质年代学白垩纪沉积序列

Microstructure Refinement and Precipitation Characteristics of TMCP-Processed Plates for Pipeline Applications

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Journal of Iron and Steel Research International 2011年第S1期18卷 482-486页

作者： Nastich S.y Morozov y.D Matrosov M.y Galkin v.v Denisov S.v I.P.Bardin Research Institute Center for Pipe and Weld Structure Steels9/232-nd Baumanskaya Str.105005MoscowRussia "MMK"-Magnitogorsky Iron and Steel Works 93Kirov Str.455002MagnitogorskRussia

The influence of technological parameters of controlled rolling and accelerated cooling (TMCP-processing) on microstructure and mechanical properties of plates with thickness of 25 mm and more at the mill "5000" of OJSC "Мagnitogorsk Iron and Steel Works" were *** necessity of formation of fine-grained ferrite-bainite microstructure without elongated areas of coarse lath bainite for achievement of DWTT properties is *** conditions and type of Nb(C,N) and (Nb,v)(C,N) particles with the size of less than 10 nm in the process of rolling and additional tempering are defined.

关键词： microalloying microstructure accelerated cooling precipitation

Sound scattering in dense granular media

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Chinese Science Bulletin 2009年第23期54卷 4327-4336页

作者： LAURENT J KHIDAS y LANGLOIS v Laboratoire de Physique des Matériaux Divisés et des Interfaces Université Paris-Est

The sound propagation in a dense granular medium is basically characterized by the ratio of wavelength to the grain size. Two types of wave transport are distinguished: one corresponds to coherent waves in the long wavelength limit, the other to short-wavelength scattered waves by the inhomogeneous contact force networks. These multiply scattered elastic waves are shown to exhibit a diffusive characteristics of transport over long distances of propagation. Determination of the transport mean free path l * and the inelastic absorption (Q-1) allows the inference of the structural properties of the material such as the heterogeneity and internal dissipation. The relevance of our experiments for seismological applications is discussed. Moreover, we apply the correlation technique of the configuration-specific sound scattering to monitoring the dynamic behaviour of the granular medium (irreversible rearrangements) under strong vibration, shearing and thermal cycling, respectively.

关键词：颗粒介质人口密集声散射扩散特征平均自由程晶粒尺寸交通工具结构特性

Electrofishing method improves evaluation of amphibian larvae abundance:a case of“beaver rivers”

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Integrative Zoology 2017年第4期12卷 345-350页

作者： yury y.DGEBUADZE Ivan v.BASHINSKIy Severtsov Institute of Ecology&Evolution Leninsky ProspectMoscowRussia

There are many locations in Russia where Eurasian beaver(Castor fiber)populations have been *** a keystone species,beavers provide wide-ranging direct and indirect impacts on aquatic *** particular,beaver-created ponds are sites for spawning and nursery places for tadpoles of the brown frogs(genus Rana).Because of such impacts,study techniques for assessing aquatic organism abundance are being *** compared two methods for estimating tadpole abundance:traditional catches by dipnet and *** results show that the dipnet catch data for the shallower ponds with larger water surface area were five times lower than that obtained by ***,we conclude that dipnet catches are not suitable for comparing the relative abundance of tadpoles in the two beaver ponds that were studied.

关键词： abundance of tadpoles beaver ponds Rana

How would preclinical Alzheimer’s disease (AD pathology) occur? An insight from a genomic instability mouse model

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Neural Regeneration Research 2021年第10期16卷 2012-2014页

作者： Chinthalapally v.Rao Hiroshi y.yamada Center for Cancer Prevention and Drug Development Department of MedicineHematology/Oncology SectionUniversity of Oklahoma Health Sciences Center(OUHSC)Oklahoma CityOKUSA

More than 95%of Alzheimer’s disease(AD)is late-onset,in which patients show clinical cognition/behavior symptoms after age *** early-onset AD that comes with mutations in genes directly involved in amyloid metabolism(APP,PSEN),genetic predispositions associated with late-onset AD are harder to pinpoint,and their mechanistic links to AD development need further *** the development mechanism of late-onset AD remains controversial,amyloid-beta accumulation,initiated in middle age,is widely accepted as the triggering event for early AD pathology(Du Bois et al.,2010;Sterling et al.,2011).

关键词： clinical Alzheimer metabolism