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Modeling the impacts of climate change on China's agriculture

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Journal of Geographical sciences 2001年第2期11卷 149-160页

作者： LIU Hui~1, LI Xiu-bin~1, Guenther Fischer~2. SUN Lai-xiang~2.(1. institute of Geographic sciences and Natural Resources Research, CAS, {2. 100101, China 2. International institute for Applied System Analysis, A-2.61 Laxenburg, Austria) institute of Geographic sciences and Natural Resources Research CAS International institute for Applied System Analysis A-2361 Laxenburg Austria

The impacts of climate change on China's agriculture are measured based on Ricardian model. By using county-level cross-sectional data on agricultural net revenue, climate, and other economic and geographical data for 12.5 agriculture-dominated counties in the period of 1985-1991, we find that both higher temperature and more precipitation will have overall positive impact on China's agriculture. However, the impacts vary seasonally and regionally. Higher temperature in all seasons except spring increases agricultural net revenue while more precipitation is beneficial in winter but is harmful in summer. Applying the model to five climate scenarios in the 2.2.s and 2.50s shows that the North, the Northeast, the Northwest, and the Qinghai-Tibet Plateau would always benefit from climate change while the South and the Southwest may be negatively affected. For the East and the Central China, most scenarios show that they may benefit from climate change. In conclusion, climate change would be beneficial to the whole China.

关键词： climate change Ricardian model China's agriculture

Regional Summer Temperature Decrease against Global Warming in China, Landform Effect?

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Journal of Mountain Science 2007年第1期4卷 86-90页

作者： LU Aigang PANG Deqian HE Yuanqing PANG Hongxi WANG Tianming GE Jianping Ministry of Education Key Laboratory for Biodiversity Science and Engineering College of Life SciencesBeijing Normal University Beijing 100875 China institute of C-eography Research Weinan Teachers College Weinan 714000 Shaanxi China Cold and Arid Regions Environmental and Engineering institute Chinese Academy of SciencesLanzhou 730000 Gansu China

The data of 16o national meteorological observatory （NMO） stations with long-term monthly temperature data for China were analyzed in this study to show the basin-centered summer temperature decrease against global warming in the past half century. The summer and winter isotherm structures of 1950s and 1990s worked out by interpolation show the isotherm structure variations： the isotherm structure generally moves northward in winter, but in summer it is characterized with separate high-temperature and low-temperature centers and the isotherm structure moves inward the centers with global warming, indicating that the temperature in the highland areas increases but that in the lowland areas decreases in the summer of the duration. The possible mechanism of the basin-centered temperature decrease in summer is discussed in this paper.

关键词： Isotherm structure seasonal variation summer temperature decrease plateau-basin effect China

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杨-顾算法在波分复用器中的应用

物理学报 1997年第9期46卷 1751-1757页

作者：吴小萍范朝阳周文清华大学电子工程系浙江大学物理系浙江大学信息与电子工程学系

把杨顾算法用在新型纯相位型解复用器的整体设计中，通过设定输入输出面Ｈ１，Ｈ２上应该具有的强度分布，来设计Ｈ１，Ｈ２相位片上应该具有的相位分布．用纯相位调制的方式实现解复用器的分光、聚焦等综合功能，大大简化了解复用器... 详细信息

把杨顾算法用在新型纯相位型解复用器的整体设计中，通过设定输入输出面Ｈ１，Ｈ２上应该具有的强度分布，来设计Ｈ１，Ｈ２相位片上应该具有的相位分布．用纯相位调制的方式实现解复用器的分光、聚焦等综合功能，大大简化了解复用器件的结构．同时在应用杨顾算法的过程中，对算法本身作了拓展，应用于输入面是二维高斯光束，在输出面仍是二维高斯光束的情形．

关键词：相位恢复波分复用器杨-顾算法集成光学器件

Reconstructing temperature change in Central East China during 601-92. AD

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Science Bulletin 2010年第34期 3946-3956页

作者： GE QuanSheng,LIU HaoLong,ZHENG jingYun & ZHANG XueZhen institute of Geographic {2. and Natural Resources Research,chinese academy of {2.,beijing 100101,China

Using historical records on first and last frost and snow,spring cultivation,David peach blossom,autumn crop harvest,grade of sea freeze and change in northern citrus boundary,we reconstructed temperature change during 601-92. *** mean temperature of the winter half-year(October to April)over Central East China during this period was about-0.2.°C higher than that of the present(1961-2.00 AD mean).During 601-82. AD,mean temperature was about-0.52.C higher than the *** 82.-92. AD,the mean temperature was 0.42.C lower than the *** temperature fluctuations were characterized by a maximum amplitude of 1.05°C at the centennial scale,1.38°C at the 50-year scale,2.02.C at the 30-year scale,and 2.3°C at the 2.-year *** were four peaks warmer than today(601-62. AD,mean of 1°C higher temperature;641-660 AD,1.44°C;701-72. AD,0.88°C;781-800 AD,0.65°C).Three cold periods were in 741-760,82.-840,and 881-900 AD,the mean temperature of which was 0.37-0.87°C lower than the present.

关键词： Sui and Tang Dynasties Central East China phenological record human impression record reconstruction of tempera-ture change

Landscape Changes from 1974 to 1995 in the Upper Minjiang River Basin, China

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Pedosphere 2006年第3期16卷 398-405页

作者： HE Xing-Yuan ZHAO Yong-Hua HU Yuan-Man CHANG Yu ZHOU Qi-Xing institute of Applied Ecology the Chinese Academy of Sciences Shenyang 110016 （China） College of Earth Science ＆ Land Resources Management Chang＇an University Xi＇an 710054 （China） Graduate School of the chinese academy of sciences Beijing 100039 （China）

Landscape changes were traced over the 2. years from 1974 to 1995 in the upper Minjiang River basin, one of the most important forest regions in China, based on satellite image interpretation to provide basic data for local decision-making as well as sustainable landscape use and management. Results revealed that landscape from 1974 to 1995 changed at the regional scale as the area of forestland decreased, while cropland, shrubland, economic forest, grassland, and built-up land increased. Landscape changes mainly occurred in forestland, shrubland, grassland, economic forest, and built-up land. Moreover, the changes among forestland, shrubland, and grassland were the largest, influencing the whole characteristics of the changes in the basin. Analysis of the changes between 1974 and 1995 in the study area indicated that landscape heterogeneity and fragmentation increased, whereas landscape connectivity decreased. There were multiple reasons for landscape changes. A principal component analysis (PCA) was used to quantitatively study driving forces of landscape changes. The PCA results showed that economic and population factors were the principal driving forces of landscape changes from 1974 to 1995 in the upper Minjiang River basin, and that PCA was a suitable method for investigating driving forces of landscape changes.

关键词： driving forces landscape change satellite image quantification principal component analysis

Non-point source pollution of Wujiang River watershed in Guizhou Province, SW China

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Acta Geochimica 2006年第S1期 141-142页

作者： Congguo TANG1,2. Congqiang LIU1 1 State Key Laboratory of Environmental Geochemistry, institute of Geochemistry, chinese academy of sciences, Guiyang 550002. China 2.Graduate School, chinese academy of sciences, beijing 100049, China

The global image of the Moon obtained by the Chang'E-1:Data processing and lunar cartography

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Science China Earth sciences 2010年第8期53卷 1091-1102页

作者： LI ChunLai1, LIU JianJun1, REN Xin1, MOU LingLi1, ZOU YongLiao1, ZHANG HongBo1, Lü Chang1, LIU JianZhong1, ZUO Wei1, SU Yan1, WEN WeiBin1, BIAN Wei1, ZHAO BaoChang2. YANG JianFeng2. ZOU xiaoDuan1, WANG Min1, XU Chun1, KONG DeQing1, WANG xiaoQian1, WANG Fang1, GENG Liang1, ZHANG ZhouBin1, ZHENG Lei1, ZHU XinYing1, LI JunDuo1 & OUYANG ZiYuan11 National Astronomical Observatories,{2., beijing 100012. China 2.Xi’an institute of Optics and Precision Mechanics,{2., Xi’an 710119, China National Astronomical Observatories Chinese Academy of Sciences Beijing China Xi’an institute of Optics and Precision Mechanics Chinese Academy of Sciences Xi’an China

The global lunar image of the first phase of chinese Lunar Exploration Program is the first image that covered all over the surface of the Moon. It will serve as a critical foundation for succeeding exploration and scientific research. In this paper, the acquisition, characteristics, and data quality of Chang'E-1 CCD image data are described in detail. Also described are the methodology and procedure of data processing. According to rule of planetary cartography, the image data have been processed, geometrically corrected, and then mosaicked and merged in a scale of 1:2.5 million. The results of data processing and charting show that the image data of Chang'E-1 CCD and their geometric precision meet the demand of charting a map in the scale of 1:2.5 million. The relative geometric positioning precision of the global image is better than 2.0 m, and the absolute geometric positioning precision is slightly better than that of the ULCN2.05 and Clementine lunar basemap (V2.0). The plane positioning precision is approximately 100-1500 m. This global image proves to be the best global image of the Moon so far in terms of space coverage, image quality, and positioning precision.

关键词： Chang’E-1 lunar CCD data processing lunar image position lunar global image

Chemical Constituents of Soft Coral Lobophytum crassum

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Chemical Constituents of Soft Coral Lobophytum crassum

Optimizing the Ex-post Trading Profits in a Financial Market

中国化学会第四届有机化学学术会议

作者： YIN, Shuai-Wen LI, xiao-Ming shi, Yan-Ping WANG, Bin-Gui (Key Laboratory of Experimental Marine Biology, {2. of Oceanology,{2., Qingdao 2.6071) (Lanzhou {2. of Chemical Physics,{2., Lanzhou 730000) (Graduate School of{2., beijing 100039)

＜正＞Lobophytum crassum is a common soft coral species that widespread in Indo-Pacific reefs. This species has been reported to contain cembranoid diterpenes, eudesmane-based diterpenoids, polyhydroxylated sterols, and other related compounds. There is no report about the chemical study of L. crassum distributed in chinese seawaters. We recently investigated the chemical constituents of this species and wish to report here the results of the isolation and structural elucidation of three new cembranolide diterpenes （1-3） along with eight other known compounds including three further cembranoid derivatives （4-6）, five sterols （7-11）, and two hydrocarbons （12. 13）. Among these metabolites, compound 1 is the first cembranolide bearing a hydroperoxyl group in the molecule that was discovered in the genus of Lobophytum, while compounds 2.and 3 have previously synthesized by biotransforma-tion from the furanocembrane diterpene, Sarcophine, but was obtained as natural products for the first time from the nature.

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运筹学学报 1997年第1期1卷 2-13页

作者： KIN LAM（Department of Finance and Decision sciences, School of Business, Hong Kong Baptist University, Hong Kong) XIANG-SUN ZHANG(institute of Applied Mathematics, The{2., beijing, China) WEI LI（Department of Finance and Decisi 香港浸会大学香港中科院应用数学所北京

Consider investing in an asset in a financial market. Given the investment returnri in day i, consider the problem of making an investmeat decision di in day i wheredi= 1,0, -1, has the meaning that the investor maintains a long, neutral or shortposition of the asset. The overall invest return over an n day period is given bywhere c=transaction cO8t and d0 = dn+1 = 0 are given. The optinization problemof maximizing IR(d) is considered. Analytic solution of the opthaation porblem isobtained. The solution is shown to be closely related to Alexander’s tilter trading ruleand has praCtical implication in applying neural network to generate trading signals ina financial maket.

关键词： filter trading rule optimization finance investment neural network training set