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中国经济发展的机遇与挑战——学习中央经济工作会议精神座谈会综述

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中国工业经济 2024年第1期 5-16页

作者：中国社会科学院工业经济研究所课题组史丹不详中国社会科学院工业经济研究所

2023.12月11—12日,中央经济工作会议在北京举行。习近平总书记出席会议并发表重要讲话,全面总结2023.经济工作,深刻分析当前经济形势,系统部署2024年经济工作。会议要求,2024年要坚持稳中求进、以进促稳、先立后破,多出有利于稳预期... 详细信息

2023.12月11—12日,中央经济工作会议在北京举行。习近平总书记出席会议并发表重要讲话,全面总结2023.经济工作,深刻分析当前经济形势,系统部署2024年经济工作。会议要求,2024年要坚持稳中求进、以进促稳、先立后破,多出有利于稳预期、稳增长、稳就业的政策,在转方式、调结构、提质量、增效益上积极进取,不断巩固稳中向好的基础。要强化宏观政策逆周期和跨周期调节,继续实施积极的财政政策和稳健的货币政策,加强政策工具创新和协调配合。为深入解读2023.中央经济工作会议精神,中国社会科学院工业经济研究所“我国发展的新战略机遇与风险挑战研究”课题组邀请7位专家学者交流学习体会,立足当前经济走势,回应当下经济热点问题,为推动高质量发展建言献策。

关键词：高质量发展宏观政策科技创新城乡融合绿色低碳

A preliminary molecular historical biogeography of Caragana (Leguminosae) based on ITS and trnL-F DNA sequence data

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Journal of Arid Land 2009年第1期1卷 64-73页

作者： MingLi ZHANG1,2, Yun KANG3., JunBo YANG4 1 Laboratory of Evolution and Biodiversity Conservation in Arid Region, Xinjiang institute of Ecology and Geography, chinese academy of sciences, Urumqi 83.011, china 2 institute of Botany, chinese academy of sciences, Beijing 100093. china 3.School of Pharmacy, Fudan University, Shanghai 20003., china 4 Kunming institute of Botany, chinese academy of sciences, Kunming 650204, china chinese Acad Sci Lab Evolut & Biodivers Conservat Arid Reg Xinjiang Inst Ecol & Geog Urumqi 830011 Peoples R China chinese Acad Sci Inst Bot Beijing 100093 Peoples R China Fudan Univ Sch Pharm Shanghai 200032 Peoples R China chinese Acad Sci Kunming Inst Bot Kunming 650204 Peoples R China

The nrDNA internal transcribed spacer (ITS) and cpDNA trnL-F internal spacer (IGS) sequence data of Caragana eight species and one outgroup Halimodendron halodendron, was employed to reconstruct a phylogenetic tree, then the area relationship was analyzed by means of component analysis (CA), Brooks parsimony analysis (BPA), and dispersal-vicariance analysis (DIVA), six areas were selected from two divided distributions of East Asia and Tethys in Caragana. The phylogenetic tree indicated that there were three distinctive groups, which were attributed to some morphological characters, first with pinnate foliage and deciduous rachis, second with palmate foliage and persistent sclerotic stick rachis, and third with pinnate foliage and persistent sclerotic stick rachis. The results of CA and BPA illustrated general area relationships. An explicit area relationship should be Altai-Sayan, Far East NE china and North china (Hengduan Mountains). DIVA recognized several explanatory vicariance and dispersal events. As the scenario of Caragana distribution pattern, it looks like the vicariance versus dispersal plays more important role. In vicaraince, there are not only the isolated far-distance vicariance, but also the adjacent vicariance especially a vicariance between Hengduan Mountains and North china.

关键词： Caragana ITS trnL-F phylogeny cladistic biogeography DIVA distribution pattern

Evolution of desertification in a two-dimensional energy balance model coupled with thermodynamics and dynamics

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Science china Earth sciences 2010年第11期53卷 1726-1733页

作者： CHAO JiPing1,2 & LI YaoKun3.4 1National Marine Environmental Forecasting Center, Beijing 100081, china 2First institute of Oceanography, State Oceanic Administration, qingdao 266061, china 3.tate Key Laboratory of Numerical Modeling for Atmospheric sciences and Geophysical Fluid Dynamics, institute of Atmospheric Physics, chinese academy of sciences, Beijing 100029, china 4Graduate University of chinese academy of sciences, Beijing 100049, china 1. National Marine Environmental Forecasting Center Beijing 100081 China2. First Institute of Oceanography State Oceanic Administration Qingdao 266061 China3. State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China4. Graduate University of Chinese Academy of Sciences Beijing 100049 China

The relationship between desert evolution and change in albedo has been investigated quasi-analytically using a zonal mean two-dimensional energy balance model which considers the radiation transmission process due to thermodynamics and bound- ary layer movement caused by kinetics. A climate state including temperature, zonal wind, meridional wind and vertical wind can be simulated according to the current zonal distribution of albedo. Given desert distribution, characterized by the value and distribution of albedo, the response of climate on albedo has been studied to analyze the evolution of desert climate. One significant result is that the simple model can reproduce mean meridional circulation. Another result indicates that climate corresponds to two equilibria. This happens when the junction temperature between vegetation and desert is higher than a certain critical value. As for the first equilibrium, the desert belt is predicted to move southward in the northern hemisphere with the increasing values of albedo, which corresponds to the current trend of climate change. For the second equilibrium, vegetation will expand northward with increasing values of albedo, which would indicate a narrowing of the desert belt. In order to determine if the two equilibria exist, new physical models are needed.

关键词： two-dimensional energy balance model desertification two equilibria

ANALYSING THE EFFICIENCY OF SOLVING DENSE LINEAR EQUATIONS ON DWNING1000

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Journal of Computational Mathematics 1996年第4期14卷 383-386页

作者： X.B. Chi(institute of Software, chinese academy of sciences, Beijing, china) 中科院软件所北京

In this paper, we consider solving dense linear equations on Dawning1000 byusing matrix partitioning technique. Based on this partitioning of matrix, we give aparallel block LU decomposition method. The efficiency of solving linear equationsby different ways is analysed. The numerical results are given on *** running our parallel program, the best speed up on 3. processors is over 25.

关键词： ANALYSING THE EFFICIENCY OF SOLVING DENSE LINEAR EQUATIONS ON DWNING1000

Application of the moist vorticity vector in the analysis of a heavy rainfall event in North china

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Progress in Natural Science:Materials International 2007年第12期17卷 1457-1465页

作者： Zhao Yu1,2,3. Wang Jianguo4 and Xue Deqiang2(1. Laboratory of Cloud-Precipitation Physics and Severe Storms, institute of Atmospheric Physics, chinese academy of sciences, Beijing 100029, china 2. Shandong Provincial Meteorological Observatory, Jinan 25003., china 3. Graduate University of chinese academy of sciences, Beijing 10003., china 4. Shandong Provincial Meteorological Bureau, Jinan 25003., china) Laboratory of Cloud-Precipitation Physics and Severe Storms Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Shandong Provincial Meteorological Observatory Jinan 250031 China Graduate University of chinese academy of sciences Beijing 100039 China Shandong Provincial Meteorological Bureau Jinan 250031 China

The moist vorticity vector (MVV), defined as (ζa×▽qv)/ρ introduced by Gao et al. is used to study a heavy rainfall event in North china. The MVV has zonal, meridional and vertical components in a three-dimensional framework. Analysis of domain-mean and mass-integrated quantities shows that the variation of the vertical component of the MVV closely follows the variation of the cloud hydrometeors, with a linear correlation coefficient of 0.95, indicating that the vertical component of the MVV is strongly associated with midlatitude convection. Further analysis shows that the vertical component of the MVV reflects the interaction between the horizontal vorticity and the horizontal specific humidity gradient, which can associate dynamic and thermodynamic processes with cloud microphysical processes. Thus, this study can help to understand how the interaction between circulations and clouds aids the development of convection, and the MVV can be used to trace the development and evolution of heavy rainfall.

关键词： moist vorticity vector heavy rainfall modeling study.

δ-WAVE FOR 1-D AND 2-D HYPERBOLIC SYSTEMS

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Journal of Computational Mathematics 1996年第3期14卷 256-262页

作者： S.L. Yang(institute of Applied Mathematics, chinese academy of sciences, Beijing, china) chinese ACAD SCI INST APPL MATHBEIJINGPEOPLES R CHINA

Here a new kind of nonlinear wave, which is called δ-wave, is described by some high resolution difference solutions for Riemann problems of one-dimensional (1-D) and two-dimensional (2-D) nonlinear hyperbolic systems in conservation laws. Some phenomena are numerically shown for the solutions of Riemann problems for 2-D gas dynamics systems

关键词： Zhang WAVE FOR 1-D AND 2-D HYPERBOLIC SYSTEMS

ELTA-WAVE IN A SIMPLE 1-D 2 x 2 HYPERBOLIC PROBLEM

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Journal of Computational Mathematics 1996年第4期14卷 311-318页

作者： S.L. Yang(institute of Applied Mathematics, chinese academy of sciences, Beijing, china) institute of Applied Mathematics Chinese Academy of Sciences Beijing China

A simple one-dimensional 2 x 2 hyperbolic system is considered in the *** model contains a linear hyperbolic equation, as well as a hyperbolic equation ofwhich the coefficients are about the solution of the linear one. The exact solution ispresented and discussed, then numerical experiments are given by TVD (or MmB)type schemes for Riemann problems. From the results, we know that the solutionsdo have δ-waves for some suitable initial data.

关键词： Zhang Figure DELTA-WAVE IN A SIMPLE 1-D 2 HYPERBOLIC PROBLEM

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, {3., Beijing 100080, china Graduate School, {3., Beijing 100080, china 1. institute of Mathematics Academy of Mathematics and System Sciences Chinese Academy of Sciences 100080 Beijing China 2. Graduate School Chinese Academy of Sciences 100080 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.

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B_c Meson Studies

高能物理与核物理 2002年第Z1期26卷 1-10页

作者： CHANG Chao-Hsi (institute of Theoretical Physics, chinese academy of sciences, Beijing 100080, china) Inst. of Theor. Phys. Chinese Acad. of Sci. Beijing 100080 China

Our studies on the meson Bc arc briefly *** decays of the meson Bc to a P-wave charmonium Xc or hc are reported comparatively precisely because they are fresh

关键词：高能物理核物理增刊张肇西 B_c Meson Studies Rev