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A novel high resolution model without open boundary conditions applied to the{1. Seas: first investigation on tides

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Acta Oceanologica Sinica 2010年第6期29卷 12-25页

作者： YU Huaming CHEN Xueen BAO Xianwen Thomas Pohlmann WU Dexing Institute of Physical Oceanography Ocean University of China Qingdao 266100 China Institute of Oceanography Centre for Marine and Climate Research University of Hamburg Hamburg 20146 Germany

We developed a Global Ocean Circulation and Tide Model （GOCTM） with coarse grids in the open deep ocean degrading ‘smoothly’ into the highly resolved china Seas （CS） of refined grids to study the tides and circulation *** is based on the framework of the Finite Volume approach for better mass conservation through improved transports across the discrete individual control *** also takes a full advantage of the geometric flexibility of unstructured mesh using a realistic global topography including the Arctic *** CS are given a special focus by refining the unstructured grids,but they are embedded into global domain ***,GOCTM not only successfully avoids the treatment of the open boundaries,but also optimizes the trade-off between computational cost and model ***,GOCTM is driven by the astronomical tide-generating potential and the secondary tide-generating potential directly,together with the wind stress and heat *** succeeds in reproducing the global eight principal tidal harmonic ***,the simulated tidal results in the CS are improved compared to some other regional models with the discrepancy of 3.9 cm for M {1.*** idea of GOCTM can also be referred for other regional ocean study.

关键词： finite volume model GOCTM open boundary conditions the china Seas

The study of two-color excitation upconversion of Pr(0.5)Yb(3):ZBLAN

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Science china(Physics,Mechanics & Astronomy) 2006年第2期49卷 169-177页

作者： CHEN Xiaobo1.& SONG Zengfu2.1. {1. Optics Beijing Area Major Laboratory, Analysis and testing center, Beijing Normal University, Beijing 1.0875, china 2. Peking University, Physics School, Beijing 1.0871. china applied Optics Beijing Area Major Laboratory Analysis testing center Beijing Normal University Beijing 100875 China Physics School Peking University Beijing 100871 China

The excited state absorption upconversion of Pr(0.5)Yb(3):ZBLAN glass material, under two-color excitation of the 960 nm semiconductor laser and the Xe lamp light simultaneously, is reported in this article. It was found that the upconversion emission spectra of 480.1. 51..0, 601.9 and 631.8 nm coincide with the common emission spectra. Meanwhile, the upconversion-excitation spectrum has three obvious peaks under two-color excitation, and they respectively correspond to the 856.0 nm upconversion ex-citation transition [1.4(Pr3+)→1.6(Pr3+) and 1.4(Pr3+)→3P1.Pr3+)], the 789.0 nm upconver-sion excitation transition 1.4(Pr3+)→3P2.Pr3+), and the 803.7 nm upconversion excitation transition 3H6(Pr3+)→1.2.Pr3+). The upconversion excitation transition 1.4(Pr3+)→1.6(Pr3+) is strong because its oscillator strength f = 2..040×1.?6 is large, which results in a large peak appearing in the upconversion excitation spectrum. That is just the new interesting two-color excitation upconversion luminescence phenomenon of Pr(0.5)Yb(3):ZBLAN induced by one laser and one continuous normal light simultaneously.

关键词： upconversion volumetric three-dimensional display two-color excitation.

Economical cascadic multigrid method (ECMG)

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Science china {1. 2007年第12期50卷 1765-1780页

作者： Zhong-ci SHI~1 Xue-jun XU~(1+) Yun-qing HUANG~2.~1 LSEC,Institute of Computational mathematics,academy of mathematics and Systems Science,chinese academy of sciences,Beijing 1.0080,china ~2.Hunan Key Laboratory for Computation and Simulation in Science and Engineering,Institute for Computational and applied mathematics,Xiangtan University,Xiangtan 411105,china LSEC Institute of Computational Mathematics Academy of Mathematics Systems Science Chinese Academy of Sciences Beijing 100080 China Hunan Key Laboratory for Computation Simulation in Science Engineering Institute for Computational applied {1. Xiangtan University Xiangtan 411105 China

In this paper, an economical cascadic multigrid method is proposed. Compared with the usual cascadic multigrid method developed by Bornemann and Deuflhard, the new one requires less iterations on each level, especially on the coarser grids. Many operations can be saved in the new cascadic multigrid algorithms. The main ingredient is the control of the iteration numbers on the each level to preserve the accuracy without over iterations. The theoretical justification is based on the observations that the error reduction rate of an iteration scheme in terms of the smoothing property is no longer accurate while the iteration number is big enough. A new formulae of the error reduction rate is employed in our new algorithm. Numerical experiments are reported to support our theory.

关键词： economical cascadic multigrid method (ECMG), cascadic multigrid method (CMG)

A three-dimensional variational ocean data assimilation system:Scheme and preliminary results

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Science china Earth {1. 2006年第11期49卷 1212-1222页

作者： ZHU Jiang1.2. ZHOU Guangqing1. YAN Changxiang1. FU Weiwei1.& YOU Xiaobao1.3 1. International Center for Climate and Environment {1., Institute of Atmospheric Physics, chinese academy of sciences, Beijing 1.002.,{2. 2. Jiangsu Key Laboratory of Meteorological Disaster, Nanjing University of Information Science and Technology, Nanjing 2.0044,{2. 3. Beijing Institute of applied Meteorology, Beijing 1.002.,{2. 1. International Center for Climate and Environment sciences Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China 2. Jiangsu Key Laboratory of Meteorological Disaster Nanjing University of Information Science and Technology Nanjing 210044 China 3. Beijing Institute of applied Meteorology Beijing 100029 China

A new 3DVAR-based Ocean Variational Analysis System (OVALS) is developed. OVALS is capable of assimilating in situ sea water temperature and salinity observations and satellite altimetry data. As a component of OVALS, a new variational scheme is proposed to assimilate the sea surface height data. This scheme considers both the vertical correlation of background errors and the nonlinear temperature-salinity relationship which is derived from the generalization of the linear balance constraints to the nonlinear in the 3DVAR. By this scheme, the model temperature and salinity fields are directly adjusted from the altimetry data. Additionally, OVALS can assimilate the temperature and salinity profiles from the ARGO floats which have been implemented in recent years and some temperature and salinity data such as from expendable bathythermograph, moored ocean buoys, etc. A 2.-year assimilation experiment is carried out by using OVALS and the Tropical Pacific circulation model. The results show that the assimilation system may effectively improve the estimations of temperature and salinity by assimilating all kinds of observations. Moreover, the root mean square errors of temperature and salinity in the upper depth less than 42. m reach 0.63℃ and 0.34 psu.

关键词： data assimilation, 3DVAR, sea surface height, ARGO floats.

Analysis on the positioning precision of CAPS

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Science china(Physics,Mechanics & Astronomy) 2009年第3期52卷 328-332页

作者： JI YuanFa1.2.& SUN XiYan1.2.1.National Astronomical Observatories, chinese academy of sciences, Beijing 1.001.0} china 2.{2. Science and Technology College, Guilin University of Electronic Technology, Guilin 541.04, china 1. National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China 2. {1. Science and Technology College Guilin University of Electronic Technology Guilin 541004 China

As a newly developed satellite positioning system, the chinese Area Positioning System (CAPS) is a typical direct sequence spread spectrum ranging system like GPS. The positioning precision of such navigation signals depends on many factors, including the pseudo-code rate, the signal to noise ratio, the processing methods for tracking loops and so on. This paper describes the CAPS link budget, the solution approach for CAPS positioning, focusing on the autocorrelation function feature of C/A code signals. The CAPS signal measurement precision is studied by the software approach together with theoretical analysis of the range resolution. Because the conventional Delay Lock Loop (DLL) is vul- nerable to the impact of noise, a narrow correlator and multiple correlators as well as the corresponding discrimination methods of phases are proposed, which improves the robustness of DLL and the code-phase resolution of the measurement. The results show that the improvement of the DLL structure and the discrimination method are the most important way to improve the ranging resolution. Theoretical analysis and experimental results show that a CAPS receiver could reach a {1.-m positioning precision by using three satellites with a supported height from an altimeter.

关键词： satellite navigation receiver narrow correlation tracking loop

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(r,k)-catching code

chinese Science Bulletin 1998年第10期43卷 812-815页

作者： LI Anping Institute of applied {1.,{2., Beijing 1.0080, china Institute of applied {1. Chinese Academy of Sciences Beijing China

A collection of r_words on an alphabet of n letters is called (r,k)_catching code if for every r_word w there is one selected member v such that v coincides with w in at least k places. How large is the smallest size of the (r,k)_catching code and how to find the minimal (r,k)_\%catching code? Some methods are advanced to construct such codes.

关键词： catching code.

Analysis of Low-polar Ginsenosides in Steamed Panax Ginseng at High-temperature by HPLC-ESI-MS/MS

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Chemical Research in chinese Universities 2012年第1期28卷 31-36页

作者： ZHANG Yu-chi1.2. PI Zi-feng1. LIU Chun-ming2. SONG Feng-rui1. LIU Zhi-qiang1.and LIU Shu-ying1.1. Changchun Center of Mass Spectrometry, Changchun Institute of applied Chemistry, chinese academy of sciences, Changchun 1.002., P. R.{2. 2. Central Laboratory, Changchun Normal University, Changchun 1.0032. P. R.{2. chinese Acad Sci Changchun Inst Appl Chem Changchun Ctr Mass Spectrometry Changchun 130022 Peoples R China Changchun Normal Univ Cent Lab Changchun 130032 Peoples R China

A high performance liquid chromatography coupled with electrospray ionization-tandem mass spectrome try（HPLC-ESI-MS/MS） method was developed for the analysis and identification of ginsenosides in the extracts of raw Panax ginseng（RPG） and steamed Panax ginseng at high temperatures（SPGHT）. A total of 2. ginsenosides were extracted include of which 1. low-polar ginsenosides, such as ginsenosides F4, Rk3, Rh4, 2.S-Rg3, 2.R-Rg3 and so on, were identified according to their HPLC retention time and MS/MS data. The results indicated that the low polar ginsenosides were seldom found in RPG. For the exploration of the transformation pattern of the ginsenosides in steam processing, the standards of ginsenosides Re, Rg1. Rb1. Rc, Rb2. Rb3 and Rd were selected and hydrolyzed at a temperature of 1.0} oC. The results show that these polar ginsenosides can be converted to low-polar ginsenosides such as Rg2. Rg6, F4, Rk3 and Rg5 by hydrolyzing the sugar chains.

关键词： Ginsenoside Hydrolysis Steamed Panax ginseng High performance liquid chromatography coupled withelectrospray ionization-tandem mass spectrometry(HPLC-ESI-MS/MS)

Real estate appraisal system based on GIS and BP neural network

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中国有色金属学会会刊：英文版 2011年第S3期21卷 626-630页

作者： LIU Xiao-sheng1. DENG Zhe1. WANG Ting-li2.1. School of Architecture and Survey Engineering, Jiangxi University of Science and Technology, Ganzhou 341.00,{1. 2. School of applied Science, Jiangxi University of Science and Technology, Ganzhou 341.00,{1. [a] School of Architecture and Survey Engineering Jiangxi University of Science and Technology Ganzhou 341000 China [b] School of applied Science Jiangxi University of Science and Technology Ganzhou 341000 China

For the inefficiency and inaccuracy of appraisal method of traditional estate appraisal theory, the real estate appraisal system based on GIS and BP neural network was established. The structure of the system was designed which includes appraisal model, trade case, GIS database and query analysis module. With the help of the L-M algorithm in MATLAB software, BP neural network was improved and the trade cases were trained, then the BP neural network which has already been trained was tested. At the same time, the BP neural and GIS were put together to construct the hedonic price estimate model. The C# and ArcGIS9.3 were used to achieve the system in VS2.08. City basic geographic data and real estate related information were used as the basic data in practice. The results show that the functions of querying, adding and editing the spatial data and attribute data are achieved and also the efficiency and accuracy of real estate are improved, so that the new method of real estate is provided by the system.

关键词： BP neural network GIS hedonic price real estate appraisal

Surface pollen and vegetation reconstruction from central and northern mountains of Taiwan

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chinese Science Bulletin 2003年第3期48卷 291-295页

作者： YU Ge1. LIEW Pingmei2. XUE Bin1.& LI Zhengyi2.1. Nanjing Institute of Geography & Limnolog of the chinese Academof sciences, Nanjing 2.0008,{2. 2. Department of Geology, Taiwan University, Taibei 1.6-1., Taiwan,{2. Nanjing Institute of Geography & Limnolog of the chinese academy of sciences Nanjing 210008 China

Surface pollen from various montane vegeta-tions in Shalixian Mt. and Lepei Mt. of central and northern Taiwan have been explored and analyzed. The pollen datawere used to simulate vegetation types by using the biomisa-tion technique. Computing three matrixes of pollen taxa,plant functional types and combined biomes, vegetation types at each site have been finally defined through the fuzselections of a tie-breaking rule. The results show that sur-face pollen data can simulate the subtropical Castanopsis andCyclobalanopsis forests, alpine warm-temperate Quercus and Quercus-Pinus forests, and alpine temperate/cool-temperate conifers of Tsuga-Picea and Picea-Abies forests. Simulatedelevations of the forests are similar to actual locations of the forests. This study can add vertical surface pollen data forextending investigation of various vegetation types in china, provide PFT schemes and vegetation types in low-latitude and montane areas, and be {1. as modern analogues for fossil pollen in order to reconstruct Quaternary

关键词：台湾省北部山区中部山区表层花粉植被重建植被类型