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    题名 作者 年代 出处 被引量
1Dynamical Framework of IAP Nine-Level Atmospheric General Circulation Model显示文摘The dynamical framework of the nine-level version of the IAP AGCM is presented in this paper. The emphasis of the model’s description is put on the following two aspects:(1) A model’s standard atmosphere, which is a satisfactory approximation to the observed troposphere and lower stratosphere standard atmosphere, is introduced into the equations of the model to permit a more accurate calculation of the vertical transport terms, especially near the tropopause; (2) The vertical levels of the model are carefully selected to guarantee a smooth dependence of layer thickness upon pressure in order to reduce the truncation error involved in the unequal interval vertical finite-differencing. For testing the model, two kinds of linear baroclinic Rossby-Haurwitz waves, one of which has a dynamically stable vertical structure and the other has a relatively unstable one, are constructed to provide initial conditions for numerical experiments. The two waves have been integrated for more than 300 days and 100 days张学洪 1990Advances in Atmospheric Sciences1990,7,1:48
2Optimization of the head shape of the CRH3 high speed train显示文摘Aiming at optimizing the head shape of the CRH3 high speed train, an efficient optimization approach is proposed. The CFD analysis by solving Navier-Stokes equations is coupled with optimization calculation based on the multi-objective genetic algorithm, meanwhile the arbitrary shape deformation technique (ASD) is also introduced into the design flow, which greatly shortens the time consumption for geometry regeneration and flow field remeshing. As a result, the efficiency of the optimization calculation is highly improved. Statistical analysis is done to the designs in the design space, and the correlation between the design variables and the objective is studied to find out the key variables that most affect the objective. Response surface analysis is also performed to get the nonlinear relationship between the key design variables and the objective with the Kriging algorithm. Finally, after the optimization, an aerodynamic performance comparison between the optimal shape and the original shape reveals that the original shape of CRH3 high speed train owns a very stable aerodynamic performance and can be trustingly used in industry.SUN ZhenXu1, SONG JingJing1 & AN YiRan1 College of Engineering, State Key Laboratory for Turbulence and Complex Systems, Peking University, Beijing 100871, China 2010Science China(Technological Sciences)2010,53,12:35
3High-Order Models of Nonlinear and Dispersive Wave in Water of Varying Depth with Arbitrary Sloping Bottom显示文摘High-order models with a dissipative term for nonlinear and dispersive wave in water of va-rying depth with an arbitrary sloping bottom are presented in this article.First,the formal derivations toany high order of μ(=h/λ,depth to deep-water wave length ratio)and ε(=α/h,wave amplitude todepth ratio)for velocity potential,particle velocity vector,pressure and the Boussinesq-type equations forsurface elevation η and horizontal velocity vector U at any given level in water are given.Then,the exactexplicit expressions to the fourth order of μ are derived.Finally,the linear solutions of η,U,C(phase ce-lerity)and C_g(group velocity)for a constant water depth are obtained.Compared with the Airy theory,excellent results can be found even for a water depth as large as the wave legnth.The present high-ordermodels are applicable to nonlinear regular and irregular waves in water of any varying depth(from shal-low to deep)and bottom slope(from mild to steep).Hong Guangwen Professor, Coastal and Ocean Engineering Research Institute, Hohai University, Nanjing 210024, P. R. China. 1997China Ocean Engineering1997,12,3:26
4Full-colour nanoprint-hologram synchronous metasurface with arbitrary hue-saturationbrightness control显示文摘The colour gamut,a two-dimensional(2D)colour space primarily comprising hue and saturation(HS),lays the most important foundation for the colour display and printing industries.Recently,the metasurface has been considered a promising paradigm for nanoprinting and holographic imaging,demonstrating a subwavelength image resolution,a flat profile,high durability,and multi-functionalities.Much effort has been devoted to broaden the 2D HS plane,also known as the CIE map.However,the brightness(B),as the carrier of chiaroscuro information,has long been neglected in metasurface-based nanoprinting or holograms due to the challenge in realising arbitrary and simultaneous control of full-colour HSB tuning in a passive device.Here,we report a dielectric metasurface made of crystal silicon nanoblocks,which achieves not only tailorable coverage of the primary colours red,green and blue(RGB)but also intensity control of the individual colours.The colour gamut is hence extruded from the 2D CIE to a complete 3D HSB space.Moreover,thanks to the independent control of the RGB intensity and phase,we further show that a singlelayer silicon metasurface could simultaneously exhibit arbitrary HSB colour nanoprinting and a full-colour hologram image.Our findings open up possibilities for high-resolution and high-fidelity optical security devices as well as advanced cryptographic approaches.Yanjun Bao Ying Yu Haofei Xu Chao Guo Juntao Li Shang Sun Zhang-Kai Zhou Cheng-Wei Qiu Xue-Hua Wang 2019Light(Science & Applications)2019,8,1:25
5Multichannel vectorial holographic display and encryption显示文摘Since its invention,holography has emerged as a powerful tool to fully reconstruct the wavefronts of light including all the fundamental properties(amplitude,phase,polarization,wave vector,and frequency).For exploring the full capability for information storage/display and enhancing the encryption security of metasurface holograms,smart multiplexing techniques together with suitable metasurface designs are highly demanded.Here,we integrate multiple polarization manipulation channels for various spatial phase profiles into a single birefringent vectorial hologram by completely avoiding unwanted cross-talk.Multiple independent target phase profiles with quantified phase relations that can process significantly different information in different polarization states are realized within a single metasurface.For our metasurface holograms,we demonstrate high fidelity,large efficiency,broadband operation,and a total of twelve polarization channels.Such multichannel polarization multiplexing can be used for dynamic vectorial holographic display and can provide triple protection for optical security.The concept is appealing for applications of arbitrary spin to angular momentum conversion and various phase modulation/beam shaping elements.Ruizhe Zhao Basudeb Sain Qunshuo Wei Chengchun Tang Xiaowei Li Thomas Weiss Lingling Huang Yongtian Wang Thomas Zentgraf 2018Light(Science & Applications)2018,7,1:15
6ON ZEROS OF ALGEBRAIC EQUATIONS——AN APPLICATION OF RITT PRINCIPLE显示文摘Let K be a basic field of characteristic 0, and fi,i=1,…,r, be polynomials in K(x1,…Xn)Consider the system of algebraic equations which defines an algebraic variety V consisting of zeros of the system in an arbitrary extension field of K. The study of the structure of V or that of the set吴文俊 1986Chinese Science Bulletin1986,31,1:14
7Geometrically constrained isogeometric parameterizedlevel-set based topology optimization via trimmed elements显示文摘In this paper, an approach based on the fastpoint-in-polygon (PIP) algorithm and trimmed elements isproposed for isogeometric topology optimization (TO)with arbitrary geometric constraints. The isogeometricparameterized level-set-based TO method, which directlyuses the non-uniform rational basis splines (NURBS) forboth level set function (LSF) parameterization andobjective function calculation, provides higher accuracyand efficiency than previous methods. The integration oftrimmed elements is completed by the efficient quadraturerole that can design the quadrature points and weights forarbitrary geometric shape. Numerical examples demon-strate the efficiency and flexibility of the method.Yingjun WANG David J. BENSON 2016Frontiers of Mechanical Engineering2016,11,4:13
8Interference-assisted kaleidoscopic meta-plexer for arbitrary spin-wavefront manipulation显示文摘Achieving simultaneous polarization and wavefront control,especially circular polarization with the auxiliary degree of freedom of light and spin angular momentum,is of fundamental importance in many optical applications.Interferences are typically undesirable in highly integrated photonic circuits and metasurfaces.Here,we propose an interference-assisted metasurface-multiplexer(meta-plexer)that counterintuitively exploits constructive and destructive interferences between hybrid meta-atoms and realizes independent spin-selective wavefront manipulation.Such kaleidoscopic meta-plexers are experimentally demonstrated via two types of single-layer spinwavefront multiplexers that are composed of spatially rotated anisotropic meta-atoms.One type generates a spinselective Bessel-beam wavefront for spin-down light and a low scattering cross-section for stealth for spin-up light.The other type demonstrates versatile control of the vortex wavefront,which is also characterized by the orbital angular momentum of light,with frequency-switchable numbers of beams under linearly polarized wave excitation.Our findings offer a distinct interference-assisted concept for realizing advanced multifunctional photonics with arbitrary and independent spin-wavefront features.A variety of applications can be readily anticipated in optical diodes,isolators,and spin-Hall meta-devices without cascading bulky optical elements.He-Xiu Xu Guangwei Hu Ying Li Lei Han Jianlin Zhao Yunming Sun Fang Yuan Guang-Ming Wang Zhi Hao Jiang Xiaohui Ling Tie Jun Cui Cheng-Wei Qiu 2019Light(Science & Applications)2019,8,1:11
9A modal theory and recursion RTCM algorithm for gratings of deep grooves and arbitrary profile显示文摘A modal theory for gratings of deep grooves and arbitrary shape is developed. The theory is implemented with an algorithm of recursion reflection-transmission coefficient matrix (RTCM). Several cases of plane wave with arbitrary polarization and arbitrary angle of incidence diffracted from gratings of deep grooves and arbitrary profile are calculated. It is found that this method is more accurate, more stable and faster than others.傅克祥 王植恒 张大跃 张靖 张奇志 1999Science China Mathematics1999,42,6:10
10Simpler criterion on W state for perfect quantumstate splitting and quantum teleportation显示文摘A simpler criterion is presented to judge whether a W state can be taken as quantum channel forperfectly splitting or teleporting an arbitrary single-qubit state. If the W state is usable,the detailed manipulations in the two quantum information processes are amply shown. Moreover,some relevant discussions are made.ZUO XueQin LIU YiMin ZHANG Wen ZHANG ZhanJun 2009Science China(Physics,Mechanics & Astronomy)2009,52,12:10
11Probabilistic Teleportation of an Arbitrary Two-particle State显示文摘A scheme for the teleportation of an arbitrary two-particle state via two non-maximally entangled particle pairsis proposed. We show that teleportation can be successfully realized with a certain probability if the receiveradopts an appropriate unitary-reduction strategy. A specific strategy is provided in detail The probability of successful teleportation is determined by the smaller coefficients of the two entangled pairs.顾永建 郑亦庄 郭光灿 2001Chinese Physics Letters2001,18,12:8
12Partition of arbitrary single-qubit information among n recipients via asymmetric(n+1)-qubit W state显示文摘A symmetric and(n,n)-threshold scheme for a sender to partition his/her arbitrary single-qubit information among n recipients is proposed by using a newly constructed asymmetric(n+1)-qubit W state.Both the scheme in some given scenarios and the new W state are also discussed given.ZHANG Wen LIU YiMin YIN XiaoFeng ZHANG ZhanJun 2009Science China(Physics,Mechanics & Astronomy)2009,52,10:7
13Generalized quantum state sharing of the arbitrary two particles state显示文摘This paper has proposed a generalized quantum state sharing protocol of an arbitrary two-particle state using non-maximally GHZ states and generalized Bell state measurement.The sender Alice performs two-particle generalized Bell state measurements on her two particles in the state sharing process and the controller takes measurements on his particles and transfers the quantum information to the receiver with entanglement swapping by the cooperation of the other agents.It is found that the use of nonmaximally entangled state in quantum state sharing has enabled the secure sharing of the quantum state.WANG Chuan 1,2,ZHANG Yong 1,2 & JIN GuangSheng 1,2 1 School of Science,Beijing University of Posts and Telecommunications,Beijing 100876,China 2 Key Laboratory of Optical Communication and Lightwave Technologies,Beijing University of Posts and Telecommunications,Beijing 100876,China 2010Science China(Physics,Mechanics & Astronomy)2010,53,11:6
14Arbitrary polarization conversion dichroism metasurfaces for all-in-one full Poincare sphere polarizers显示文摘The control of polarization,an essential property of light,is of broad scientific and technological interest.Polarizers are indispensable optical elements for direct polarization generation.However,arbitrary polarization generation,except that of common linear and circular polarization,relies heavily on bulky optical components such as cascading linear polarizers and waveplates.Here,we present an effective strategy for designing all-in-one full Poincare sphere polarizers based on perfect arbitrary polarization conversion dichroism and implement it in a monolayer all-dielectric metasurface.This strategy allows preferential transmission and conversion of one polarization state located at an arbitrary position on the Poincare sphere to its handedness-flipped state while completely blocking its orthogonal state.In contrast to previous methods that were limited to only linear or circular polarization,our method manifests perfect dichroism of nearly 100%in theory and greater than 90%experimentally for arbitrary polarization states.By leveraging this attractive dichroism,our demonstration of the generation of polarization beams located at an arbitrary position on a Poincare sphere directly from unpolarized light can substantially extend the scope of meta-optics and dramatically promote state-of-the-art nanophotonic devices.Shuai Wang Zi-Lan Deng Yujie Wang Qingbin Zhou Xiaolei Wang Yaoyu Cao Bai-Ou Guan Shumin Xiao Xiangping Li 2021Light(Science & Applications)2021,10,2:6
15THE BERNSTEIN TYPE INEQUALITY AND SIMULTANEOUS APPROXIMATION BY INTERPOLATION POLYNOMIALS IN COMPLEX DOMAIN显示文摘In this paper we investigate simultaneous appoximation for arbitrary system of nodes on smooth domain in complex plane. Some results which are better than those of known theorems are obtained.涂天亮 1991Acta Mathematica Scientia1991,11,2:6
16A flutter-effect-based triboelectric nanogenerator for breeze energy collection from arbitrary directions and self-powered wind speed sensor显示文摘Triboelectric nanogenerators(TENGs)have been developed rapidly into an efficient wind energy collection equipment.Reducing the frictionwear and energy loss in breeze energy collection is a research direction worthy of attention.Herein,a flutter-effect-based triboelectricnanogen erator(FE-TENG)is designed to collect the breeze energy at low wind speed from arbitrary directions.Distinguishing from previouswind-driven TENGs,the wind-driven part of this device is separated from the TENG units,which not only avoids the wear of friction layerscaused by direct wind contact but also reduces the energy loss,therefore,relatively stable electric outputs are obtained with Voc-281 V,Isc-13.4μA,Qsc-143 nC,and output power-4 mW at the wind speed of 4.5 m/s,respectively.In addition,a real-time wind speed monitoringsystem based on LabVIEW software with high sen sitivity and fast response to wind is achieved relying on the excellent linear relation shipbetween wind speed and electrical output signal.Furthermore,it has been successfully applied as power sources for portable electronics,about 170 commercial light-emitting devices(LEDs)are lighted and a digital watch is successfully driven at the wind speed of 2.9 m/s.This worknot only provides a new structure and idea for the future collection of clean and sustainable breeze energy from arbitrary directions but also hasgreat potential in the field of self-powered systems.Jie Hu Xianjie Pu Hongmei Yang Qixuan Zeng Qian Tang Dazhi Zhang Chenguo Hu Yi Xi 2019Nano Research2019,12,12:6
17Computer analysis of arbitrary reinforced concrete cross-section under bieccentric load刁波 叶英华 Siu-Shu Eddie LAM 2000Progress in Natural Science:Materials International2000,10,4:5
18Concise and efficient direct-view generation of arbitrary cylindrical vector beams by a vortex half-wave plate显示文摘A concise, efficient, and practical direct-view scheme is presented to generate arbitrary cylindrical vector(CV)beams, including CV beams, vortex beams, and cylindrical vector vortex(CVV) beams, by a vortex half-wave plate(VHP). Six kinds of first-order and other high-order CV beams, such as azimuthally polarized(AP) beams, antivortex radial polarization mode beams, and three-order AP beams, are formed by simply rotating a half-wave plate. The Stokes parameters and double-slit interference of multitype CV beams are investigated in detail.The polarization parameters, including degree of polarization, polarization azimuth, and ellipticity, are obtained,which demonstrates the efficient generation of CV beams. In addition, the double-slit interference experiment is introduced in the setup, and fringe misplacement and tilt appear for CVV beams, in which the misplacement number M is 2P+1 for P ≤ 2 and 2P-1 for P ≥ 3, where P is the polarization order number, and the fringe tilt offset is positively related to the topological charge number l of CVV beams. In addition, new types of VHPs can be formed by cascading two or more VHPs when the types of available VHPs are limited, assisting in more flexible generation of multitype CV beams. It is experimentally demonstrated that arbitrary CV beams with high quality are effectively achieved by the proposed setup, and the double-slit interference method can be utilized to determine and analyze CV beams rapidly and concisely by practical performance, which shows the potential to be implemented as a commercial device.JUNLI QI WEIHUA WANG BO SHI HUI ZHANG YANAN SHEN HAIFEI DENG WENJING PU XIN LIU HUIHUI SHAN XIAOMIN MA LIANQIANG ZHANG WEI LU MEICHENG FU XIUJIAN LI 2021Photonics Research2021,9,5:4
19MULTIPLE SOLUTICNS OF NONLINEAR FREDHOLM INTEGRAL EQUATIONS IN BANACH SPACES显示文摘In this paper, the author uses the topological degree theory to investigate the multiple solutions of nonlinear Fredholm integral equations in Banach spaces. Two new theorems aro obtained and two examples are given.郭大钧 1989Chinese Annals of Mathematics,Series B1989,10,4:4
20A geometrical and physical nonlinear finite element model for spatial thin-walled beams with arbitrary section显示文摘Based on the theories of Bernoulli-Euler beams and Vlasov's thin-walled members,a new geometrical and physical nonlinear beam element model is developed by applying an interior node in the element and independent interpolations on bending angles and warp,in which factors such as traverse shear deformation,torsional shear deformation and their coupling,coupling of flexure and torsion,and second shear stress are all considered.Thereafter,geometrical nonlinear strain in total Lagarange(TL) and the corresponding stiffness matrix are formulated.Ideal plastic model is applied to physical nonlinearity to comply with the yield rule of Von Mises and incremental relationship of Prandtle-Reuss.Elastoplastic stiffness matrix is derived by numerical integration on the basis of the finite segment method.Examples show that the developed model is feasible in analysis of thin-walled structures with high accuracy.YANG QingShan 1 &WANG XiaoFeng 2 1 School of Civil Engineering,Beijing Jiaotong University,Beijing 100044,China 2 College of Civil Engineering,Tongji University,Shanghai 200092,China 2010Science China(Technological Sciences)2010,53,3:4
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