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Current status and future of acid rain in china

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chinese Science Bulletin 1997年第24期42卷 2076-2081页

作者： DING Guo’an, XU Xiaobing, FANG Xiumei, JIN Shaping, XU Xia, Tang Jie, LIU Qijun, WANG Shufeng and WANG Wenxing1. chinese academy of meteorological sciences, beijing 100081, china 2. chinese academy of Environment sciences, beijing 100012, china chinese academy of meteorological sciences Beijing 100081 China

As a part of the national key project of acid rain research, chemical element analysis of rainwater has been carried out based on observation of acid rain network in chinese meteorologicalAdministration over the years of 1992 and 1993. Samples of precipitation collected from eachacid rain station were taken according to the standard established by chinese meteorologicalAdministration. pH value was measured with pH meter (accuracy of 0. 01) made in

关键词： acid rain current status future.

THE DUAL MIXED METHOD FOR AN UNILATERAL PROBLEM

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Journal of Computational Mathematics 2003年第6期21卷 733-746页

作者： Lie-heng Wang(LSEC, ICMSEC, academy of Mathematics and System sciences, chinese academy of sciences,beijing 100080, china) LSEC ICMSEC Academy of Mathematics and System Sciences Chinese Academy of Sciences Beijing 100080 China

In this paper, the dual mixed method for an unilateral problem, which is the simplified modelling of scalar function for the friction-free contact problem, is considered. The dual mixed problem is introduced, the existence and uniqeness of the solution of the problem are presented, and error bounds O(h3/4) and O(h3/2) are obtained for the dual mixed finite element approximations of Raviart-Thomas elements for k = 0 and k = 1 respectively.

关键词： Dual Mixed Method Unilateral Problem.

meteorological observations on Mount Everest in 2005

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Progress in Natural Science:Materials International 2007年第7期17卷 828-837页

作者： Xie Aihong~(1**) Qin Dahe~1 Ren Jiawen~1 Qin Xiang~1 Xiao Cunde~(1,2) Hou Shugui~1 Kang Shichang~(1,3) Yang Xingguo~(1,4) Jiang Youyan~1 (1.Key Laboratory of Cryosphere and Environment,Cold and Arid Regions Environment and Engineering Research Institute,chinese academy of sciences,Lanzhou 730000,china 2.chinese academy of meteorological Science,beijing 100081,china 3.Institute of Tibetan Plateau Research,chinese academy of sciences,beijing 100085,china 4.Gansu Provincial meteorological Bureau,Lanzhou 730000,china) Key Laboratory of Cryosphere and Environment Cold and Arid Regions Environment and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China

Mount Everest,the highest point on the Earth is often referred to as the earth's third pole as such the place is relatively inaccessible and little is known about its *** April 2005,an automatic weather station was installed at the mountain's North Col(6523 m a.s.l.).According to the observational 10-minute mean and daily records,the meteorological characteristics were analyzed. All the meteorological elements displayed obvious diurnal variations during May 1 to July 22,*** monthly variation of daily meteo- rological elements on Mount Everest coincided with that on Dingri,the closest routine meteorological station,with the high correlation co- efficients of 0.928,0.877,0.682,0.755,0.826 and 0.676(n=83,p3,0.485 and 0.487(n=83,pmeteorological *** conclusions are much important for research on meteorology and climate changes in the region.

关键词： Mount Everest meteorological observation Dingri County radiation air temperature relative humidity air pressure wind

COMPOSITE-STEP LIKE FILTER METHODS FOR EQUALITY CONSTRAINT PROBLEMS

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Journal of Computational Mathematics 2003年第5期21卷 613-624页

作者： Pu-yan Nie(LSEC, ICMSEC, academy of Mathematics and System sciences, chinese academy of sciences, beijing 100080, china) 中科院数学与系统科学院 LSEC ICMSEC CAS 北京 100080

In a composite-step approach, a step Sk is computed as the sum of two components Uk and hk. The normal component Vk, which is called the vertical step, aims to improve the linearized feasibility, while the tangential component hk, which is also called horizontal step, concentrates on reducing a model of the merit functions. As a filter method, it reduces both the infeasibility and the objective function. This is the same property of these two methods. In this paper, one concerns the composite-step like filter approach. That is, a step is tangential component hk if the infeasibility is reduced. Or else, Sk is a composite step composed of normal component Uk, and tangential component hk.

关键词： Composite-step like approaches Filter methods Equality constraints Sequen- tial quadratic programming(SQP) algorithms Normal component Tangential component Convergence.

Transformations and non-degenerate maps

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Science china Mathematics 2005年第z1期48卷 195-205页

作者： LI Baokui & WANG Yuefei Institute of Mathematics, academy of Mathematics and System sciences, chinese academy of sciences, beijing 100080, china Graduate School, chinese academy of sciences, beijing 100080, china Institute of Mathematics Academy of Mathematics and System Sciences Chinese Academy of Sciences Beijing China Graduate School Chinese Academy of Sciences Beijing China

We shall prove the equivalences of a non-degenerate circle-preserving map and a M(o)bius transformation in ^Rn, of a non-degenerate geodesic-preserving map and an isometry in Hn of a non-degenerate line-preserving map and an affine transformation in Rn. That a map is non-degenerate means that the image of the whole space under the map is not a circle, or geodesic or line respectively. These results hold without either injective or surjective, or even continuous assumptions, which are new and of a fundamental nature in geometry.

关键词： M(o)bius transformation, circle-preserving map, non-degenerate map.

A CLASS OF NEW PARALLEL HYBRID ALGEBRAIC MULTILEVEL ITERATIONS

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Journal of Computational Mathematics 2001年第6期19卷 651-672页

作者： Zhong-zhi Bai (LSEC ICMSEC, academy of Mathematics and Systems sciences, chinese academy of sciences, beijing 100080, china) 中科院计算数学与科学工程计算所北京 100080

Presents preconditioning matrices having parallel computing function for the coefficient matrix and a class of parallel hybrid algebraic multilevel iteration methods for solving linear equations. Solution to elliptic ... 详细信息

关键词： elliptic boundary value problem system of linear equations symmetric positive definite matrix multilevel iteration parallel method

CONVERGENCE OF NONLINEAR CONJUGATE GRADIENT METHODS

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Journal of Computational Mathematics 2001年第5期19卷 539-548页

作者： Yu-hong Dai (LSEC, ICMSEC, academy of Mathematics and Systems sciences, chinese academy of sciences,beijing 100080, china) 中科院计算数学与科学工程计算所北京 100080

Presents a study on methods for unconstrained optimization. Assumptions of the study; Main results; Convergence properties of the methods under simplified Armijo-type line search.

关键词： unconstrained optimization conjugate gradient (generalized) line search global convergence

Thermal analysis of the baffle structure of the Solar Space Telescope

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Science china(Physics,Mechanics & Astronomy) 2010年第9期53卷 1755-1764页

作者： LI Rong1,2,3 & WANG Sen1,3 1 National Astronomical Observatories,chinese academy of sciences,beijing 100012,china 2 Graduate University of chinese academy of sciences,beijing 100049,china 3 Key Laboratory of Solar Activity,National Astronomical Observatories of chinese academy of sciences,beijing 100012,china chinese academy of sciences National Astronomical Observatories Beijing China (GRID:grid.9227.e) (ISNI:***) Graduate University of chinese academy of sciences Beijing China (GRID:grid.458514.9) National Astronomical Observatories of chinese academy of sciences Key Laboratory of Solar Activity Beijing China (GRID:grid.450302.0) (ISNI:***) chinese academy of sciences National Astronomical Observatories Beijing China (GRID:grid.9227.e) (ISNI:***) National Astronomical Observatories of chinese academy of sciences Key Laboratory of Solar Activity Beijing China (GRID:grid.450302.0) (ISNI:***)

The SST(Space Solar Telescope) is an astronomical telescope with a primary mirror of 1 m in *** observes the sun with a small view field to ensure that its high spatial resolution imaging has 0.1″-0.15″ and high SNR(signal to noise ratio).Surrounding the small view field is still the sun,which is an intense source of both heat and stray *** baffles(the main baffle,the aperture,and the outer baffle),which are used to eliminate the stray light,will change the thermal flux in the SST and will weaken the effect of the thermal control *** this study,the compatibility analysis of the thermal effect of baffle structures in SST is *** GCF(Geometry Composing Function) and BRDF(Bidirectional Reflectance Distribution Function),which are two inherent related parameters in the compatibility analysis,are *** objective and method of the compatibility analysis are *** the thermal analysis software,the temperature fields are calculated for different lengths of the main baffle,different radii of apertures,different lengths of the outer baffle with a 3' tilt angle and 16' tilt angle,and different tilt angles of the outer baffle with a 200 mm length.A series of configurations and sizes of the baffles are studied with the goals of both thermal control and elimination of stray *** design of the baffle structure of SST is achieved:the main baffle of length 4100 mm,the internal shield of radius 494 mm,the outer baffle of length 200 mm,and the outer baffle of tilt angle 3' are successfully *** paper presents the relationship between the thermal control design and stray light elimination plan in the *** aims of the optimal design of the baffle structure of SST are *** thoughts and methods of the optimal analysis are also useful for similar optical telescopes designed for solar observation.

关键词： baffle the main baffle the outer baffle GCF BRDF

CO_2 background concentration in the atmosphere over the chinese mainland

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chinese Science Bulletin 2002年第14期47卷 1217-1220页

作者： WANG Gengchen, WEN Yupu, KONG Qinxin, REN Lixin & WANG MulinInstitute of Atmospheric Physics, chinese academy of sciences, beijing, 100029, china academy of meteorological sciences, china meteorological Administration, beijing 100086, china Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China academy of meteorological sciences China Meteorological Administration Beijing China

Based on the long-term monitoring data on CO2 concentration, variation trend and characteristics of CO2 background concentration in the atmosphere over the chinese mainland are analyzed. Results show that the increasing trend of CO2 background concentration in the atmosphere over the chinese mainland has appeared during the period of 1991-2000. The average annual CO2 growth increment is 1.59μL/L, and the average annual CO2 growth rate is 0.44%. Distinct seasonal variations of CO2 background concentration are observed, and the averaged amplitude of CO2 seasonal variations is 10.35μL/L. Regional variation characteristics of CO2 background concentration in the atmosphere and possible impact of human activities on these variations over the chinese mainland are discussed as well.

关键词： CO2 background concentration chinese mainland CO2 growth rate CO2 seasonal variation CO2 regional variation CO2 variation trend.