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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 1. institute of Engineering Thermophysics Chinese Academy of Sciences 100080 Beijing China 2. institute of Mechanics Chinese Academy of Sciences 100080 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.

The influence of tropical Indian Ocean warming on the Southern Hemispheric stratospheric polar vortex

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Science china Earth sciences 2009年第3期52卷 323-332页

作者： LI ShuangLin Nansen-Zhu International Research Centre, institute of Atmospheric physics, chinese academy of sciences, beijing 100029, china Nansen-Zhu International Research Centre Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

During the past decades, concurrent with global warming, most of global oceans, particularly the tropical Indian Ocean, have become warmer. Meanwhile, the Southern Hemispheric stratospheric polar vortex (SPV) exhibits a deepening trend. Although previous modeling studies reveal that radiative cooling effect of ozone depletion plays a dominant role in causing the deepening of SPV, the simulated ozone-depletion-induced SPV deepening is stronger than the observed. This suggests that there must be other factors canceling a fraction of the influence of the ozone depletion. Whether the tropical Indian Ocean warming (IOW) is such a factor is unclear. This issue is addressed by conducting ensemble atmospheric general circulation model (AGCM) experiments. And one idealized IOW with the amplitude as the observed is prescribed to force four AGCMs. The results show that the IOW tends to warm the southern polar stratosphere, and thus weakens SPV in austral spring to summer. Hence, it offsets a fraction of the effect of the ozone depletion. This implies that global warming will favor ozone recovery, since a warmer southern polar stratosphere is un-beneficial for the formation of polar stratospheric clouds (PSCs), which is a key factor to ozone depletion chemical reactions.

关键词： tropical Indian Ocean warming Southern Hemispheric stratospheric polar vortex atmospheric general circulation model ensemble experiments planetary wave

Precursory SST anomalies associated with the convection over the western Pacific warm pool

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chinese Science Bulletin 2002年第8期47卷 696-699页

作者： LU Riyuinstitute of Atmospheric physics, chinese academy of sciences, beijing 100080, china (e-mail: lr@***) institute of Atmospheric physics Chinese Academy of Sciences Beijing China

The convection over the tropical western Pacific warm pool influences significantly the atmospheric circulation and climate in East Asia. Thus, the precursory signals of the convection may be used in the forecast of summer climate in china. According to the present results, the June-July-August (JJA) mean convection intensity over the warm pool is significantly related to the precursory positive and negative sea surface temperatures (SSTs) in the warm pool and in the equatorial central and eastern Pacific, respectively. It is also related to the simultaneous negative surface temperatures west to the Philippines. The analysis on the SSTs associated with the convection over the warm pool in individual month of summer shows that for the convection in June and July, there are precursory SST signals in the warm pool and the equatorial central and eastern Pacific. Therefore, this study shows that only the convection in June and July, rather than that in August, has precursory SST signals, despite the

关键词： warm pool convection precursory SSTs El Nino.

How big are the Csorgo-Revesz increments of two-parameter Wiener processes?

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Science china Mathematics 2004年第6期47卷 894-907页

作者： WANG WenshengDepartment of Mathematics, Hangzhou Teacher’s College, Hangzhou 310012, china institute of Applied Mathematics, chinese academy of sciences, beijing 100080, china Dept. of Math. Hangzhou Teacher's Coll. Hangzhou 310012 China Inst. of Appl. Math. Chinese Acad. of Sci. Beijing 100080 China

In this paper, we prove a theorem on the set of limit points of the increments of a two-parameter Wiener process via establishing a large deviation principle on the increments of the two-parameter Wiener process.

关键词： two-parameter Wiener process increment functional law of the iterated logarithm large deviation.

SYNTHESIS AND PROPERTIES OF ANILING ANILING AND 0-AMINOBENZENESULFONIC ACID COPOLYMER

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chinese Journal of Polymer Science 1999年第2期17卷 165-170页

作者： Jun-hua Fan Mei-xiang Wan Dao-ben Zhu institute of Chemistry, chinese academy of sciences, beijing 100080, china institute of Chemistry Chinese Academy of Sciences Beijing 100080 China

Poly(aniline- co-o-aminobenzenesulfonic acid) (PAOABSA) as a water soluble conducting polymerwas synthesized by chemical polymerization. The productivity and the room-temperature conductivity of thecopolymer were measured as a function of the reaction conditions, such as reaction temperature, the ratio ofoxidant to monomer and the degree of sulfonation defined as the ratio of sulfur to nitrogen atoms(S/N). Themain results obtained are summarized as follows : (1) lower reaction temperature (at about 0℃) is favorablefor the enhancement of the room-temperature conductivity of the copolymer; (2) higher content of oxidant isunfavorable for increasing the room-temperature conductivity of the copolymer; (3) both productivity androom-temperature conductivity of the copolymer decrease with increase of the degree of sulfonation whichwas always lower than 0.5 even an excess of o-aminobenzenesulfonic acid was added, probably because thereactivity ratio of aniline (γ=2.99± 0.05) is much higher than that of o-aminobenzenesulfonic acid (γ_2 = 0.06±0.02) estimated by using Fineman-Ross method and least square method.

关键词： Watersoluble polyaniline Reactivity ratio Copolymer

Prediction model for spring dust weather frequency in North china

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Science china Earth sciences 2008年第5期51卷 709-720页

作者： LANG XianMei Center for Disastrous Climate Research and Prediction, institute of Atmospheric physics, chinese academy of sciences, beijing 100029, china Center for Disastrous Climate Research and Prediction Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

It is of great social and scientific importance and also very difficult to make reliable prediction for dust weather frequency (DWF) in North china. In this paper, the correlation between spring DWF in beijing and Tianjin observation stations, taken as examples in North china, and seasonally averaged surface air temperature, precipitation, Arctic Oscillation, Antarctic Oscillation, South Oscillation, near surface meridional wind and Eurasian westerly index is respectively calculated so as to construct a prediction model for spring DWF in North china by using these climatic factors. Two prediction models, i.e. model-I and model-II, are then set up respectively based on observed climate data and the 32-year (1970 -2001) extra-seasonal hindcast experiment data as reproduced by the nine-level Atmospheric General Circulation Model developed at the institute of Atmospheric physics (IAP9L-AGCM). It is indicated that the correlation coefficient between the observed and predicted DWF reaches 0.933 in the model-I, suggesting a high prediction skill one season ahead. The corresponding value is high up to 0.948 for the subsequent model-II, which involves synchronous spring climate data reproduced by the IAP9L-AGCM relative to the model-I. The model-II can not only make more precise prediction but also can bring forward the lead time of real-time prediction from the model-I’s one season to half year. At last, the real-time predictability of the two models is evaluated. It follows that both the models display high prediction skill for both the interannual variation and linear trend of spring DWF in North china, and each is also featured by different advantages. As for the model-II, the prediction skill is much higher than that of original approach by use of the IAP9L-AGCM alone. Therefore, the prediction idea put forward here should be popularized in other regions in china where dust weather occurs frequently.

关键词： spring dust weather frequency prediction model iap9l-agcm hindcast experiment real-time prediction

A shortest path algorithm for moving objects in spatial network databases

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Progress in Natural Science:Materials International 2008年第7期18卷 893-899页

作者： Xiaolan Yin a,b,*, Zhiming Ding c, Jing Li a a Technology Center of Software Engineering, institute of Software, chinese academy of Science, P.O. Box 8718, beijing 100080, china b Graduate University, chinese academy of sciences, beijing 100049, china c Technology Center of Basic Software, institute of Software, chinese academy of sciences, beijing 100080, china Technology Center of Software Engineering Institute of Software Chinese Academy of Science P.O. Box 8718 Beijing 100080 China Graduate University Chinese Academy of Sciences Beijing 100049 China Technology Center of Basic Software Institute of Software Chinese Academy of Sciences Beijing 100080 China

One of the most important kinds of queries in Spatial Network Databases (SNDB) to support location-based services (LBS) is the shortest path query. Given an object in a network, e.g. a location of a car on a road network, and a set of objects of interests, e.g. hotels, gas station, and car, the shortest path query returns the shortest path from the query object to interested objects. The studies of shortest path query have two kinds of ways, online processing and preprocessing. The studies of preprocessing suppose that the interest objects are static. This paper proposes a shortest path algorithm with a set of index structures to support the situation of moving objects. This algorithm can transform a dynamic problem to a static problem. In this paper we focus on road networks. However, our algorithms do not use any domain specific information, and therefore can be applied to any network. This algorithm’s complexity is O(klog2i), and traditional Dijkstra’s complexity is O((i + k)2).

关键词： Moving object Spatial network databases Shortest path index Shortest path

Multisymplectic Structure and Multisymplectic Scheme for the Nonlinear Ware Equation

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Acta Mathematicae Applicatae Sinica 2002年第1期18卷 169-176页

作者： Yu-shun WANG, Meng-zhao QINLASG, institute of Atmospheric physics, chinese academy of sciences, beijing 100029, chinainstitute of Computational Mathematics, academy of Mathematics and System sciences, chinese academy of sciences, beijing 100080, china LASG Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China institute of Computational Mathematics Academy of Mathematics and System Sciences Chinese Academy of Sciences Beijing China

The multisymplectic structure of the nonlinear wave equation is derived directly from the variational principle. In the numerical aspect, we present a multisymplectic nine points scheme which is equivalent to the multisymplectic Preissman scheme. A series of numerical results are reported to illustrate the effectiveness of the scheme.

关键词： Multisymplectic structure Multisymplectic schemes Nonlinear wave equation

SUBSPACE SEARCH METHOD FOR A CLASS OF LEAST SQUARES PROBLEM

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Journal of Computational Mathematics 2000年第2期18卷 133-140页

作者： Zi-Luan Wei (institute of Computational Mathematics and Scientific / Engineerin Computing, chinese academy of sciences, P.O. Box 2719, beijing 100080, china) 中科院计算数学与科学工程计算所北京 100080

Presents information on a study which described a subspace search method for solving a class of least squares problem. Derivation of the algorithm; Convergence results; Modification of algorithm and applications.

关键词： subspace search method A class of least squqres problem convergence analysis.