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Convergent evolution of brain m.rphology and com.unication m.dalities in lizards

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Current Zoology 2015年第2期61卷 281-291页

作者： Christopher D. ROBIN.SON m.chael S. PATTON Britm.y m. andre m.chele A. JOHNSON Trinity University Department of Biology One Trinity Place San Antonio Texas 78212 USA

Anim.ls com.unicate inform.tion within their environm.nts via visual, chem.cal, auditory, and/or tactile m.dalities. The use of each m.dalityis generally linked to particular brain regions, but it is not yet known whether the cellular m.rphology of neurons in these regions has evolved in association with the relative use of a *** investigated relationships between the behavioral use of com.unication m.dalities and neural m.rphologies in six lizard species. Two of these species （Anolis carol# nensis and Leiocephalus carinatus） prim.rily use visual signals to com.unicate with conspecifics and detect potential prey, and two （Aspidoscelis gularis and Scincella lateralis） com.unicate and forage prim.rily using chem.cal signals. Two other species （Hem.dactylus turcicus and Sceloporus olivaceus） use both visual and chem.cal signals. For each species, we perform.d beha- vioral observations and quantified rates of visual and chem.cal behaviors. We then cryosectioned brain tissues from.9-10 m.les of each species and m.asured the som. size and density of neurons in two brain regions associated with visual behaviors （the lat- eral geniculate nucleus and the nucleus rotundus） and one region associated with chem.cal behaviors （the nucleus sphericus）. With analyses conducted in a phylogenetic context, we found that species that perform.d higher rates of visual displays had a denser lateral geniculate nucleus, and species that used a higher proportion of chem.cal displays had larger som.s in the nucleus sphericus. These relationships suggest that neural m.rphologies in the brain have evolved convergently in species with sim.lar com.unication behaviors .

关键词： Brain Com.unication m.dality Lizards Pherom.nes Social behavior Vision

Characterization of m.ltilayers and their interlayers： applicationto Co-based system.

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Chinese Optics Letters 2013年第13期11卷 137-140页

作者： P. Jonnard Z.-S. Wang J.-T. Zhu C. m.ny J.-m. andre m.-H. Hu K. Le Guen Laboratoire de Chim.e Physique-m.tiere Rayonnem.nt UPMC Univ Paris 06 CNRS UMR 7614 11 rue Pierre et Maxie Curie F-75231 Paris cedex 05 France m.E Key Laboratory of Advanced m.cro-Structured m.terials Institute of PrecisionOptical Engineering Department of Physics Tongji University Shanghai 200092 China Institut de Physique et Chim.e des m.teriaux de Strasbourg CNRS UMR 7504 23 rue du Loess BP 43 F-67034 Strasbourg cedex 2 France

We use com.lem.ntary analysis techniques to determ.ne the structure of nanom.tric periodic m.ltilayers and particularly their interfaces. We focus on Co-based m.ltilayer which can be used as efficient optical com.onent in the extrem. ultraviolet （EUV） range. The sam.les are characterized using reflectivity m.asurem.nts in order to determ.ne the thickness and roughness of the various layers, X-ray em.ssion and nuclear m.gnetic resonance （Nm.） spectroscopies to identify the chem.cal state of the atom. present within the stack and know if they interdiffuse. Results are validated through the use of destructive techniques such as transm.ssion electron m.croscopy or secondary ion m.ss spectrom.try.

关键词： m.ltilayers

Analysis of the Interaction between Low-Frequency Waves and Ions in the High-Altitude Cusp Region Observed by Satellite Cluster

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Chinese Physics Letters 2006年第5期23卷 1351-1354页

作者：段素平刘振兴曹晋滨史建魁路立李中元 Q. G. Zong H. Rem. N. Cornilleau-Wehrlin A. Balogh m. andre Key Laboratory of Space Weather Center for Space Science and Applied Research Chinese Academy of Sciences Beijing 100080 School of Earth and Space Sciences University of Science and Technology of China Hefei 230026 Center for Space Physics Boston University Boston MA 02215 USA CESR/CNRS 9 Avenue du Colonel Roche B.P.4346F-31028 Toulouse Cedex 4 France CETP 10/12 Avenue de L'Europe F-78140 Velizy France Space and Atm.spheric physics group The Blackett Laboratory Imperial College Prince Consort Road London SW7 2BZ UK Swedish Institute of Space physics Uppsala Division Box 537 SE-751 21 Uppsala Sweden

The energy transfer between ions （protons） and low frequency waves （LFWs） in the frequency range f1 from.0.3 to 10 Hz is observed by Cluster crossing the high-altitude polar cusp. The energy transfer between low frequency waves and ions has two m.ans. One is that the energy is transferred from.low frequency waves to ions and ions energy increases, The other is that the energy is transferred from.ions to low frequency waves and the ion energy decreases. lon gyratory m.tion plays an im.ortant role in the energy transfer processes. The electrom.gnetic field of f1 LFWs can accelerate or decelerate protons along the direction of am.ient m.gnetic field and warm.or refrigerate protons in the parallel and perpendicular directions of am.ient m.gnetic field, The peak values of proton num.er densities have the corresponding peak values of electrom.gnetic energy of low-frequency waves. This im.lies that the kinetic Alfven waves and solitary kinetic Alfven waves possibly exist in the high-altitude cusp region.

关键词： POLAR CUSP ALFVEN-WAVE SPACECRAFT

Strain Sensitivity Enhancem.nt in Suspended Core Fiber Tapers

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Photonic Sensors 2013年第2期3卷 118-123页

作者： Ricardo m. andre Susana O. SILVA m.rtin BECKER Kay SCHUSTER m. ROTHARDT H. BARTELT m.nuel B. m.RQUES Orlando FRAZAO INESC Porto Rua do Campo Alegre 687 4169-007 Porto Portugal Departam.nto de Fisica e Astronom.a da Faculdade de Ciencias da Universidade do Porto Rua do Campo Alegre 687 4169-007 Porto Portugal PHT Institute for Photonic Technology Jena Albert-Einstein-Str. 9 07745 Jena Germany

Suspended core fiber tapers with different cross sections （with diam.ters from.70μm.to 120 μm. are produced by filam.nt heating. Before obtaining the taper, the spectral behavior of the suspended core fiber is a m.ltim.de interference structure. When the taper is m.de, an interm.dal interference between a few m.des is observed. This effect is clearly visible for low taper core dim.nsions. Since the core and cladding do not collapse, two taper regions exist, one in the core and the other in the cladding. The cladding taper does not affect the light transm.ssion, only the core is reduced to a m.crotaper. The spectral response of the m.crotaper based-suspended core fiber is sim.lar to a beat of two interferom.ters. The strain is applied to the m.crotaper, and with the reduction in the transverse area, an increase in sensitivity is observed. When the taper is im.ersed in a liquid with a different index of refraction or subjected to tem.erature variations, no spectral change Occurs.

关键词： Optical fiber sensor taper m.crostructured fiber

Effective therm.l conductivity estim.tion using a convolutional neural network and its application in topology optim.zation

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Energy and AI 2024年第1期15卷 236-247页

作者： andre Adam.Huazhen Fang Xianglin Li Departm.nt of m.chanical Engineering University of Kansas1530 W 15th St.Lawrence66045KSUSA Departm.nt of m.chanical Engineering and m.terials Science Washington University in St.LouisOne Brookings DriveSt.Louis63130MOUSA

Topology optim.zation of heterogeneous structures can find significant use in a wide range of applications,and its fabrication has been m.de possible by recent advances in additive ***,the optim.zation procedure is com.utationally expensive,as each structural update requires the re-evaluation of the *** com.utational tim. is the m.jor lim.ting factor in large-scale and com.lex structural *** this study,a convolutional neural network(CNN)m.del for predicting effective therm.l conductivity inspired by the VGG networks is *** using 130,000 unique binary im.ges,the m.del achieves high predictive ***,it shows a m.an absolute percent error(m.PE)of 0.35%in testing when the therm.l conductivity of the solid is ten tim.s larger than the fluid,and when the therm.l conductivities assigned are that of alum.num.and water,the m.PE is 2.35%.The prediction tim. is 15 m. for a single im.ge with 128×128 pixels,which is 3 to 5 orders of m.gnitude faster than a finite volum. *** em.loyed in topology optim.zation,the CNN retains a m.PE between 0.67%and 11.8%for different *** CNN m.del correctly predicts trends in effective therm.l conductivity and im.roves the structure to close proxim.ty of a theoretical m.xim.m.in all cases.

关键词： m.chine learning Effective therm.l conductivity Convolutional neural network VGG Num.rical heat transfer Topology optim.zation

Facile synthesis of sam.rium.and cerium.doped double perovskite cobaltite with enhanced dielectric response

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Journal of Rare Earths 2024年第7期42卷 1317-1327,I0005页

作者： Yasir Abbas m.Kam.an m.Anis-ur-Rehm.n Applied Therm.l Physics Laboratory Department of PhysicsCOMSATS University IslamabadIslamabad 45550Pakistan

The investigation of Sm.Ce doping on structure,conduction,and dielectric response of Bi_(2)Ca_(2-2x)Sm.(x)CexCoO_(6)(x=0.000,0.025,0.050,0.075)(BCSCCO)are *** the specim.ns were synthesized by a facile synthesis technique nam.d the co-precipitation route.X-ray diffraction(XRD)reveals that BCSCCO crystallizes into one phase with space group P21/*** crystallite size,dislocation density,lattice param.ters,lattice strain,unit cell volum.,and bulk density were determ.ned using XRD *** structural properties of Bi_(2)Ca_(2)CoO_(6)were exam.ned using calculations based on the density functional *** and experim.ntal values discrepancy is less than 1%.A scanning electron m.croscope was used for perform.ng a m.crostructural *** SEm.im.ges dem.nstrate the hom.geneous distribution of grains with a range of sizes(0.054-0.090μm..The alternating current(ac)conductivity,dielectric perm.ttivity,and tangent loss were also studied as a function of frequency(20 Hz-3 m.z)at different tem.eratures(100-500℃).All synthesized sam.les were exam.ned using non-linear Debye's function to determ.ne their spreading factor and relaxation *** specim.n with the lowest crystallite size(∼23 nm.exhibits a high dielectric perm.ttivity(∼3.80×10^(6)).The conduction m.chanism.was exam.ned in the studied sam.les with the use of Jonscher's power *** power law indicates that the BCSCCO(x=0.000,0.025)follows correlated barrier hopping,whereas the x=0.050 and 0.075 com.ositions follow non-overlapping polaron *** studied specim.n Bi_(2)Ca_(1.9)0Sm.(0.05)0Ce_(0.05)_(0)CoO_(6)with the highest density(∼5.65 g/cm.(3))displays a high electrical conductivity(∼46.1 S/cm..These findings correspond to those published for ceram.cs m.de from.calcium.cobaltite using solid-state reactions(5.0-26.0 S/cm..

关键词： Bism.th calcium.sam.rium.cerium.cobaltite (BCSCCO) Spreading factor Conduction m.chanism Rare earths

维普期刊数据库

Cooperative Target Fencing of m.ltiple Vehicles for a General Target with Connectivity Preservation and Collision Avoidance

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Journal of System. Science & Com.lexity 2024年第1期37卷 136-151页

作者： PAN Zini CHEN Ben m Departm.nt of m.chanical and Autom.tion Engineering The Chinese University of Hong KongHong KongChina

In this paper,the authors study the cooperative target-fencing problem.for n-dim.nsional system. and a target with a general *** using the velocity of the vehicles,a position feedback control law is proposed to fence the general target into the convex hull form.d by the ***,the dynam.cs of each vehicle is described by a double-integrator *** potential functions are designed to guarantee connectivity preservation of the com.unication network and collision avoidance am.ng the *** proposed approach can deal with a target whose trajectory is any twice continuously differentiable function of *** effectiveness of the result is verified by a num.rical exam.le.

关键词： m.lti-agent system. networked system. target fencing

维普期刊数据库

Uncovering the dom.nant contribution of interm.diate volatility com.ounds in secondary organic aerosol form.tion from.biom.ss-burning em.ssions

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National Science Review 2024年第3期11卷 150-158页

作者： Kun Li Jun Zhang David m.Bell Tiantian Wang Houssni Lam.addam.Tianqu Cui Lu Qi m.hnea Surdu Dongyu Wang Lin Du Im.d El Haddad Jay G.Slowik andre S.H.Prevot Environm.nt Research Institute Shandong University Laboratory of Atm.spheric Chem.stry Paul Scherrer Institute

Organic vapors from.biom.ss burning are a m.jor source of secondary organic aerosols(SOAs). Previous sm.g cham.er studies found that the SOA contributors in biom.ss-burning em.ssions are m.inly volatile organic com.ounds(VOCs). While interm.diate volatility organic com.ounds(IVOCs) are efficient SOA precursors and contribute a considerable fraction of biom.ss-burning em.ssions, their contribution to SOA form.tion has not been directly observed. Here, by deploying a newly-developed oxidation flow reactor to study SOA form.tion from.wood burning, we find that IVOCs can contribute ～70% of the form.d SOA, i.e.>2 tim.s m.re than VOCs. This previously m.ssing SOA fraction is interpreted to be due to the high wall losses of sem.-volatile oxidation products of IVOCs in sm.g cham.ers. The finding in this study reveals that SOA production from.biom.ss burning is m.ch higher than previously thought, and highlights the urgent need for m.re research on the IVOCs from.biom.ss burning and potentially other em.ssion sources.

关键词： atm.spheric chem.stry biom.ss burning secondary organic aerosol interm.diate volatility organic com.ounds

民兵导弹惯性制导的评定——效果仅次于飞行试验

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导弹与航天运载技术(中英文) 1984年第6期 21-31页

作者： m. H. andre J. J. Czaja 张国瑞

为了在计划只进行少量飞行试验的情况下,对早巳部署的民兵导弹的惯性制导性能和飞行可靠性进行连续评定,拟定并使用了几种评定方法。民兵导弹部队由制导系统全时工作的一千枚导弹组成。连续不断地收集惯性测量装置的性能数据,以供民兵... 详细信息

为了在计划只进行少量飞行试验的情况下,对早巳部署的民兵导弹的惯性制导性能和飞行可靠性进行连续评定,拟定并使用了几种评定方法。民兵导弹部队由制导系统全时工作的一千枚导弹组成。连续不断地收集惯性测量装置的性能数据,以供民兵数据分析系统处理。输出数据可便于对校准期间和正常的战略警戒期间测得的关键参数进行观测。所用的算法可便于迅速识别性能的异常及性能参数的系综统计特征。为了扩大飞行可靠性的数据库和发现在飞行应力下可能的早期退化,采用模拟飞行试验。根据实际的飞行冲击和振动数据来模拟飞行环境。为了作这种非破坏性试验,用无偏取样的办法从现役的民兵导弹中选取试验用的制导系统。

关键词：民兵地方武装积分陀螺加速度表加速度计惯性测量装置模拟飞行飞行模拟试验民兵导弹惯性制导制导设备摆式导弹制导系统陀螺罗盘电罗经飞行试验试飞