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On the parameterization scheme of gravity wave drag effect on the mean zonal flow of mesosphere

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chinese Science Bulletin 2003年第10期48卷 1020-1023页

作者： GAO Shouting & RAN Lingkun State Key laboratory of Atmosphere physics and Chemistry (LAPC), institute of Atmospheric physics, chinese academy of sciences, beijing 100029, china State Key laboratory of Atmosphere physics and Chemistry (LAPC) Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

Based on McFarlane抯 parameterization scheme of gravity wave drag, a refined gravity-wave-drag scheme is presented. Both the drag effect of the momentum flux and the dissipation effect of gravity wave breaking on the mean zonal flow are included in the refined parameterization scheme. The dissipation effect can be formulated with the gravity wave numbers and the mean quantities. The refined parameterization scheme may represent a complete drag effect of stationary gravity wave breaking on the mean zonal flow.

关键词：参数化法重力波阻纬向气流中间层大气动力学

Some key technics of drop tower experiment device of national Microgravity laboratory (china) (NMLC)

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Science china(Technological sciences) 2005年第3期48卷 305-316页

作者： ZHANG Xiaoqian 1 , YUAN Longgen 1 , WU Wendong 1 , TIAN Lanqiao 2 & YAO Kangzhuang 2 1. institute of Engineering Thermophysics, chinese academy of sciences, beijing 100080, china 2. institute of Mechanics, chinese academy of sciences, beijing 100080, china institute of Engineering Thermophysics Chinese Academy of Sciences Beijing China institute of Mechanics Chinese Academy of Sciences Beijing China

Drop tower is an important ground based facility for microgravity science experiment. The technical performances of the drop tower NMLC are advanced compared with similar facilities in the US, Germany and Japan. The main components such as drop capsule, deceleration devices, release mechanism present its advantages and creativities.

关键词： drop tower facility,drop capsule,deceleration devices,release mechanism.

Ambient noise near the sea-route

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Science china(physics,Mechanics & Astronomy) 2009年第1期52卷 40-45页

作者： HE Li1,2, LI ZhengLin1,3 & PENG ZhaoHui1 1 national laboratory of Acoustics, institute of Acoustics, chinese academy of sciences, beijing 100190, china 2 institute of Geology and Geophysics, chinese academy of sciences, beijing 100029, china 3 NanHai laboratory of Acoustics, institute of Acoustics, chinese academy of sciences, Haikou 570206, china national laboratory of Acoustics Institute of Acoustics Chinese Academy of Sciences Beijing China institute of Geology and Geophysics Chinese Academy of Sciences Beijing China NanHai laboratory of Acoustics Institute of Acoustics Chinese Academy of Sciences Haikou China

Ambient noise data measured in an experiment conducted in shallow water near a sea-route were analyzed. It was observed that, at low frequency, the horizontal correlation has an obvious difference from that predicted by the classical ambient noise model. The theoretical analyses show that this phenomenon is caused by wind noise together with the discrete shipping noise nearby. An ambient noise model was proposed to include the effects caused by both the noise sources. Data measured at different times verify that the proposed model can be used to forecast the ambient noise field in shallow water near the sea-route.

关键词： ambient noise model horizontal correlation discrete ships

Comparison of dark energy models:A perspective from the latest observational data

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中国科学：物理学、力学、天文学英文版 2010年第9期53卷 1631-1645页

作者： LI Miao1,2,LI XiaoDong2,3 & ZHANG Xin1,4 1Kavli institute for Theoretical physics china,chinese academy of sciences,beijing 100190,china 2Key laboratory of Frontiers in Theoretical physics,institute of Theoretical physics,chinese academy of sciences,beijing 100190,china 3Interdisciplinary Center for Theoretical Study,University of Science and Technology of china,Hefei 230026,china 4Department of physics,College of sciences,Northeastern University,Shenyang 110004,china Kavli institute for Theoretical physics china Chinese Academy of Sciences Beijing China Key laboratory of Frontiers in Theoretical physics Institute of Theoretical Physics Chinese Academy of Sciences Beijing China Interdisciplinary Center for Theoretical Study University of Science and Technology of China Hefei China Department of physics College of Sciences Northeastern University Shenyang China

We compare some popular dark energy models under the assumption of a flat universe by using the latest observational data including the type Ia supernovae Constitution compilation,the baryon acoustic oscillation measurement from the Sloan Digital Sky Survey,the cosmic microwave background measurement given by the seven-year Wilkinson Microwave Anisotropy Probe observations and the determination of H0 from the Hubble Space *** comparison statistics such as the Bayesian and Akaike information criteria are applied to assess the worth of the *** statistics favor models that give a good fit with fewer *** on this analysis,we find that the simplest cosmological constant model that has only one free parameter is still preferred by the current *** other dynamical dark energy models,we find that some of them,such as the αdark energy,constant w,generalized Chaplygin gas,Chevalliear-Polarski-Linder parametrization,and holographic dark energy models,can provide good fits to the current data,and three of them,namely,the Ricci dark energy,agegraphic dark energy,and Dvali-Gabadadze-Porrati models,are clearly disfavored by the data.

关键词： dark energy models observational constraints model comparison information criteria

Properties of the 3/2^-[521] band in the odd-N rare-earth nuclei

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Science china(physics,Mechanics & Astronomy) 2011年第S1期54卷 37-43页

作者： CHEN Liang1,2, ZHOU XiaoHong1,2, ZHANG YuHu1, ZHANG ShuangQuan3 & ZHU LiHua4 1institute of Modern physics, chinese academy of sciences, Lanzhou 730000, china 2Graduate University of chinese academy of sciences, beijing 100049, china 3State Key laboratory of Nuclear physics and Technology, School of physics, Peking University, beijing 100871, china 4china institute of Atomic Energy, beijing 102413, china institute of Modern physics Chinese Academy of Sciences Lanzhou China Graduate University of chinese academy of sciences Beijing China State Key laboratory of Nuclear physics and Technology School of Physics Peking University Beijing China china institute of Atomic Energy Beijing China

High-spin states in 161Er have been studied experimentally via the 150Nd(16O, 5n) reaction at a beam energy of 86 MeV. Three rotational bands built on the 5/2+[642], 3/2-[521], and 11/2-[505] configurations have been extended up to high-spin states, and particularly, the α = -1/2 branch of the ground state 3/2-[521] band has been revised significantly. It is found that signature inversion occurs in the 3/2-[521] band after the band crossing in 161Er. The systematics of the signature inversion associated with the 3/2-[521] configuration in the rare-earth region is discussed. The band properties are analyzed within the framework of a triaxial particle-rotor model, and a triaxial deformation is proposed to the 3/2-[521] band.

关键词： high-spin states signature inversion triaxial particle-rotor model

ON THE ERROR ESTIMATE OF LINEAR FINITE ELEMENT APPROXIMATION TO THE ELASTIC CONTACT PROBLEM WITH CURVED CONTACT BOUNDARY

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Journal of Computational Mathematics 2000年第6期18卷 561-566页

作者： Lie-heng Wang (State Key laboratory of Scientific and Engineering Computing, institute of Computational Mathematics, academy of Mathematics and System sciences, chinese academy of sciences, beijing 100080, china) 中科院计算数学所科学与工程计算国家重点实验室北京 100080

In this paper, the linear finite element approximation to the elastic contact problem with curved contact boundary is considered. The error bound O(h[sup ?]) is obtained with requirements of two times continuously differentiable for contact boundary and the usual regular triangulation, while *** et. al. Obtained the error bound O(h[sup ?]) with requirements of three times continuously differentiable for contact boundary and extra regularities of triangulation (c.f. [2]). [ABSTRACT FROM AUTHOR]

关键词： contact problem finite element approximation

Characterization of plastic flow in two Zr-based bulk metallic glasses

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Science china(Technological sciences) 2006年第4期49卷 414-424页

作者： XING Dongmei1,2, ZHANG Taihua1, LI Weihuo3 & WEI Bingchen3 1. State Key laboratory of Nonlinear Mechanics (LNM), institute of Mechanics, chinese academy of Sci- ences, beijing 100080, china 2. College of physics and Electronic Information Science, Tianjin Normal University, Tianjin 300074, china 3. national Microgravity laboratory, institute of Mechanics, chinese academy of sciences, beijing 100080, china State Key laboratory of Nonlinear Mechanics (LNM) Institute of Mechanics Chinese Academy of Sciences Beijing China College of physics and Electronic Information Science Tianjin Normal University Tianjin China national Microgravity laboratory Institute of Mechanics Chinese Academy of Sciences Beijing China

Plastic deformation behaviors of Zr65Al10Ni10Cu15 and Zr52.5Al10Ni10Cu15Be12.5 bulk metallic glasses (BMGs) are studied by using the depth-sensing nanoindentation, microindentation and uniaxial compression. The Be-containing BMG exhibits a signifi- cantly improved overall plastic strain compared with the Be-free alloy during compressive tests. Both BMGs show a loading-rate-dependent serrated flow during nanoindentation measurements, but the Be-containing alloy exhibits a much lower critical loading rate for the disappearance of the serration than the Be-free BMG. The shear band patterns de- veloped during plastic deformation are investigated by microindentation technique, wherein much higher shear band density is found in the Be-containing alloy than in the Be-free alloy, indicating an easier nucleation of shear bands in the former BMG. The dif- ference in the plastic deformation behavior of the two BMGs can be explained by a free volume model.

关键词： Bulk metallic glass, plastic deformation, shear band, nanoindentation.

A cumulant-based parameter estimation algorithm for near-field sources

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Progress in Natural Science:Materials International 2007年第8期17卷 900-905页

作者： Liang Junli~(1,2*) Yang Shuyuan~(1,2) Zhang Junying~3 (1.institute of Acoustics,chinese academy of sciences,beijing 100080,china 2.Graduate School,chinese academy of sciences,beijing 100039,china 3.national laboratory of Radar Signal Processing,Xidian University,Xi'an 710071,china) institute of Acoustics Chinese Acad. of Sci. Beijing 100080 China Graduate School Chinese Acad. of Sci. Beijing 100039 China national laboratory of Radar Signal Processing Xidian University Xi'an 710071 China

To efficiently use the array aperture and avoid the complicated parameter pairing computation,this paper proposes a new cumulant-based algorithm for localizing near-field narrowband ***,this algorithm proposes a symmetric uniform linear ar- ray (ULA),and constructs three cumulant matrices by using the fourth-order cumulants of some properly chosen sensor outputs;second- ly,unlike the conventional parallel factor (PARAFAC) analysis models in data or subspace domain,it forms a three-way array (TWA) in the fourth-order cumulant domain using the three matrices,and analyzes the uniqueness of its low-rank decomposition;thirdly,it jointly estimates the frequency,the direction-of-arrival (DOA),and the range of each near-field source from the matrices via the low-rank de- composition of the *** simulation results are presented to validate the performance of our proposed method.

关键词： array signal processing localization cumulant parallel factor (PARAFAC) analysis three-way array (TWA)

Relaxation of Chain Extension of Amorphous PET Fiber Above the Glass Transition Temperature

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chinese Chemical Letters 2000年第10期11卷 925-928页

作者： Xin LINGHU, Jun ZHAO, Rui SONG, Qing Rong FAN (Polymer physics laboratory, Center of Molecular Science, institute of Chemistry, chinese academy of sciences, beijing, 100080) Polymer physics laboratory Center of Molecular Science Institute of Chemistry Beijing 100080 China

The recovery of amorphous PET fiber in global chain orientation but nearly random segmental orientation (GOLR) state was studied by the hot shrinkage measurement above the glass transition temperature. The relaxation curves in the form of di-exponential decay were acquired and the change of two special times with the variation of treating temperature and residual recovery ratio ' was discussed.

关键词： GOLR state PET recovery of chain extension hot shrinkage measurement.