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Astronomical function and date of the Taosi observatory

science china(Physics,Mechanics & Astronomy) 2009年第1期52卷 151-158页

作者： WU JiaBi1, CHEN MeiDong2 & LIU CiYuan3 1 National Astronomical Observatories, chinese academy of sciences, beijing 100012, china 2 institute for the history of natural science, chinese academy of sciences, beijing 100010, china 3 National Time Service Center, chinese academy of sciences, Xi’an 710600, china National Astronomical Observatories Chinese Academy of Sciences Beijing China institute for the history of natural science Chinese Academy of Sciences Beijing China National Time Service Center Chinese Academy of Sciences Xi’an China

The Taosi site in Xiangfen County,Shanxi Province,may be the capital of the King Yao. Archeologists recently discovered a large semi-circular stamped-earth platform, II FJT1,which has a clear and definite pounded-earth central core together with a curved wall perforated by twelve gaps. The platform is said to be an ancient observatory used to determine the seasons by watching the sunrise. Each feature of II FJT1 was precisely measured and the data are reproduced in this paper. An astronomical analysis of slots E2 and E12 was carried out using the azimuths of the slots' centerlines and the vertical angle of the mountain ridge opposite, above which the sun rises. The results show that at present the sun is close to the two slots but does not exactly enter them at summer and winter solstice sunrise. Using 14C analysis archeologists dated the site to about 2100 BC. Because of the secular change in the obliquity of the ecliptic,at that date on the summer solstice the half-risen sun would have appeared inside slot E12 just to the right of the centerline,and on the winter solstice the sun would have been exactly on the centerline of slot E2. This result provides compelling proof that II FJT1 is an ancient observatory.

关键词： astro-archeology astro-chronology Taosi culture ancient observatory time service

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On the origin of movable metal-type technique

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chinese science Bulletin 1998年第20期43卷 1681-1692页

作者： PAN Jixing institute for history of science, chinese academy of sciences, beijing 100010, china institute for history of science Chinese Academy of Sciences Beijing China

china is the birthplace of woodblock, copperplate and non metal_type printing, movable metal_type technique, as the product of combination of copperplate and non metal_type technique, also originated in china. However, the problem on the origin of metal_type has not well been solved for a long time. This paper proved that metal_type was cast and used for paper money printing in china since the early 12th century, copper_type and tin_type technique was further developed during the 13th to 14th centuries, on the basis of investigation of excavated findings, textual research and scientific judgment. Finally a comparative research of the early metal_type technique in china, Korea and Europe was briefly discussed. A lot of unearthed material evidence were provided here.

关键词： china origin copperplate copper_type tin_type Song_Jin Yuan Ming.

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On the origin of printing in the light of new archaeological discoveries

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chinese science Bulletin 1997年第12期42卷 976-981页

作者： PAN Jixinginstitute for history of Natoral science, chinese academy of sciences, beijing 100010, china institute for Histoty of Natoral science Chinese Academy of Sciences Beijing China

30 years have passed since a printed dharani sutra scroll was discovered in 1966 in Kyongju, Korea. However, there have been different views about the date and place of its printing and publication in Korea and abroad. Some Korean scholars think that it was translated into chinese from Sanskrit in 704 in china and printed during 706-751 in the Silla period in Korea. After a further research it is now proved that this sutra was translated into chinese in 701 and printed in the follow-ing year, 702, in Luoyang, during the reign of Empress Wu. This shows that the sutra could not have been printed in the Silla period. The discoveries of the Saddharma pundarik sutra printed during 690-699 and the Sanskrit dharani charm printed around 650-670 in china also show that the dharani sutra found in Korea is not the earliest one. Both literary records and archaeological findings prove that printing originated in china.

关键词： origin printing china dharani sutra

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Relationship between Environmental Pollution of Coal Mine and Spectral Characteristics of Nearby Plants

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Journal of University of science and Technology beijing 2001年第1期8卷 10-14页

作者： Liqing Lei institute of Geographic sciences and natural Resources Research, chinese academy of sciences, beijing 100101, china Inst. of Geogr. Sci./Nat. Rsrc. Res. Chinese Academy of Sciences Beijing 100101 China

Remote sensing technology, as the most advanced method for collecting data, along with the common ways often used in the past on research of environmental science, was integrated to study the relationship between environmental pollution of coal mine and spectral characteristics of nearby plants. With compositive index and mean reflectivity at near infrared, a regression equation was established, and a conclusion was made that spectral reflectivity can be used to distinguish regions with different pollution degree. Through testing with real status of the research region, it is verified that this kind of integration and conclusion not only are helpful for human being in controlling the movement law of pollutants and the corresponding change of coal mine environmental quality but also bring a new way for the research of environment problems of coal mine.

关键词： remote sensing spectral characteristics reflectivity pollution index compositive index atmospheric pollution

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PROBABILISTIC NUMERICAL APPROACH FOR PDE AND ITS APPLICATION IN THE VALUATION OF EUROPEAN OPTIONS

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Journal of Computational Mathematics 2001年第6期19卷 591-600页

作者： Dong-sheng Wu (institute of Systems science, academy of Mathematics and Systems sciences, chinese academy of sciences, beijing 100080, china ) 中科院系统科学所北京 100080

Presents a probabilistic numerical approach for a class of probabilistic differential equation. Application of the Brownian motion and Monte-Carlo method; Application in the valuation of European Options.

关键词： Brownian motion probabilistic numerical solution European Options

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Thresholds of geographic environmental elements in sediment yield of drainage basins

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science china Earth sciences 2005年第2期48卷 230-240页

作者： CHEN Hao, ZHOU Jinxing, CAI Qiangguo, LU Zhongchen & LI Zhongyan institute of Geographic sciences and natural Resources Research, chinese academy of sciences, beijing 100101, china institute of Forestry science, chinese academy of Forestry science, beijing 100091, china Research Center for Eco-Environment sciences, chinese academy of sciences, beijing 100085, china Computing institute of science and Engineering, North china Electric Power University, beijing 102206, china institute of Geographic sciences and natural Resources Research Chinese Academy of Sciences Beijing China institute of Forestry science Chinese Academy of Forestry Science Beijing China Research Center for Eco-Environment sciences Chinese Academy of Sciences Beijing China Computing institute of science and Engineering North China Electric Power University Beijing China

Threshold of environmental elements in drainage basin sediment yield refers to, under effect of climate, underlying surface and human activity, a turning point of abrupt changes in drainage sediment yield related to environmental element characteristics. Previous studies on threshold of sediment yield of relevant drainage basins were mainly concentrated on impact of natural zones with a few researches on impact of other environmental elements. Particularly studies on compound environmental element threshold in drainage basin sediment yield remain blank today. Studies indicate that sediment yield in drainage basins is affected by compound interactions and complex actions. Based on single element analysis, the present paper gives quantitatively compound threshold of environmental elements affecting sediment yield of the drainage basin between Hekouzhen and Tongguan in the middle Yellow River by the method of multi-variant, polynomial formula regression analysis.

关键词： middle Yellow River, environmental element, sediment, sediment delivery mudule, threshold.

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Trend of urban system structure under the restriction of water and land resources in Xinjiang

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chinese science Bulletin 2006年第A1期51卷 179-188页

作者： ZHANG Xiaolei & LEIJun Xinjiang institute of Ecology and Geography, chinese academy of sciences, Urumqi 830011, china institute of Geographical science and natural Resources Research, chinese academy of sciences, beijing 100101, china Graduate School, chinese academy of sciences, beijing 100039, china Xinjiang institute of Ecology and Geography Chinese Academy of Sciences Urumqi China institute of Geographical science and natural Resources Research Chinese Academy of Sciences Beijing China Graduate School Chinese Academy of Sciences Beijing China

根据在 Xinjiang 影响城市的开发和城市的系统结构的水和陆地资源上的研究，这篇论文分析利用地位和城市的水资源的缺乏。城市的水资源的消费和浪费在一个增加趋势，这被考虑。然而，在 Xinjiang 的大多数城市和镇在水资源的缺乏水资源... 详细信息

根据在 Xinjiang 影响城市的开发和城市的系统结构的水和陆地资源上的研究，这篇论文分析利用地位和城市的水资源的缺乏。城市的水资源的消费和浪费在一个增加趋势，这被考虑。然而，在 Xinjiang 的大多数城市和镇在水资源的缺乏水资源的废物是严肃的，特别在小镇上。megapolis 和中等城市的发展被有限陆地资源显然限制。尽管有扩展小城市和镇的相对大的空格，水和陆地资源的输出好处是低的。为了完成城市的系统的顺序的扩大，在 Xinjiang 组织，在都市化的快速的发展拿一个圆和三条带和节俭资源的策略的城市的空间发展模式被建议。

关键词：城镇体系结构水资源土地资源供水能力新疆

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CONVERGENCE AND SUPERCONVERGENCE OF HERMITE BICUBIC ELEMENT FOR EIGENVALUE PROBLEM OF THE BIHARMONIC EQUATION

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Journal of Computational Mathematics 2001年第2期19卷 139-142页

作者： Dong-sheng Wu (institute of Systems science, academy of Mathematics and Systems sciences, chinese academy of sciences, beijing 100080, china ) 中科院系统科学所北京 100080

Provides information on a study which discussed the convergence and superconvergence for eigenvalue problem of the biharmonic equation using the Hermite bicubic element. Discussion on eigenvalue problem for biharmonic equation; Background on asymptotic error expansions and interpolation postprocessing; Superconvergence approximations to the eigenvalue and eigenfunction.

关键词： Hermite bicubic element biharmonic equation interpolation postprocessing eigenvalue problem

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Rocky Land Desertification and its Driving Forces in the Karst Areas of Rural Guangxi,Southwest china

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Journal of Mountain science 2008年第4期5卷 350-357页

作者： LIU Yansui WANG Jieyong DENG Xiangzheng institute of Geographic sciences and natural Resources Research Chinese Academy of Science Beijing 100101 China institute of Geographic sciences and natural Resources Research Chinese Academy of Science Beijing loolo~ ChinaGraduate University of Chinese Academy of Sciences Beijing 100039 China

With a subtropical climate,Guangxi Zhuang Autonomous Region has a typical karst *** desertification has become a serious environmental issue due to its high vulnerability caused by the joint effect of natural settings and human activities,because of which its eco-environment has been deteriorated in recent years,and farmland has been disappearing sharply at the same ***,in turn,has exacerbated the poverty level in the rural areas of the *** this study,we monitored the spatial distribution of rocky land desertification and its temporal evolution using Landsat TM/ETM images of 1985,1995,2000 and *** also analyzed the driving forces of the desertification and its *** constructing regression models by using all the relevant variables and considering the lagged effects as well as fixed effects,we quantified the exact role of different factors causing rocky land desertification in the study area with some new *** new findings in this study are greatly helpful for preserving,restoring and reconstructing the degraded mountain environment in Guangxi and other karst areas in Southwest china,and also for alleviating poverty in the rural areas in the future.

关键词： Rocky land desertification karstmountain area rural poverty driving force Guangxi Southwest china

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CONVERGENCE OF VORTEX METHODS FOR 3-D EULER EQUATIONS

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Journal of Computational Mathematics 2000年第3期18卷 239-250页

作者： Jia-fu Lin (institute of System science, academy of Mathematics and System sciences, chinese academy of sciences, beijing, 100080, china School of Mathematical sciences, Peking University, beijing 100871, china) 中科院系统科学所北京 100080

Presents a study on the convergence of vortex methods for the three-dimensional Euler equations in bounded domains. Related studies on the convergence of vortex methods; Formulation of vortex methods; Convergence for ... 详细信息

关键词： Euler equations vortex methods convergence initial-boundary value problem

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