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Modeling the Roles of Precipitation Increasing in Glacier Systems Responding to Climate Warming—Taking Xinjiang Glaciated Region as Example

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Journal of Mountain science 2005年第4期2卷 306-312页

作者： WANG Xin XIE Zichu LIU Shiyin TAO Jianjun HAN Yongshun YANG Yuelong Research institute of Geo-spatial Information science Hunan University of Science ＆ Technology Xiangtan 411201 Hunan China Key Laboratory of Ice Core and Cold Region＇s Environment Cold and Arid Regions Environmental and Engineering Research Institute CAS Lanzhou 730000 China institute of Resources and Environment Hunan Normal University Changsha 410081 China institute of Tibetan Plateau Research CAS Beijing 100029 China

The studies on prediction of climate in Xinjiang almost show that the precipitation would increase in the coming 50 years, although there were surely some uncertainties in precipitation predictions. On the basis of the structure of glacier system and nature of equilibrium line altitude at steady state （ELAo）, a functional model of the glacier system responding to climate changes was established, and it simultaneously involved the rising of summer mean temperature and increasing of mean precipitation. The results from the functional model under the climatic scenarios with temperature increasing rates of 0.01, 0.03 and 0.05 K/year indicated that the precipitation increasing would play an evident role in glacier system responding to climate change： if temperature become 1 ℃ higher, the precipitation would be increased by 10%, which can slow down the glaciers retreating rate in the area by 4 %, accelerate runoff increasing rate by 8 % and depress the ELAo rising gradient by 24 m in northern Xinjiang glacier system where semi-continental glaciers dominate, while it has corresponding values of only 1%, 5 % and 18m respectively in southern Xinjiang glacier system, where extremely continental glaciers dominate.

关键词： Glacier system climate warming precipitation increasing role

Microstructure Characteristics of Interaction Layer of Zn-Al Eutectic Alloy with Al_2O_3p/6061Al Composites

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Journal of Materials science & Technology 2004年第4期20卷 401-404页

作者： Jiuchun YAN, Zhiwu XU, Shixiong LU and Shiqin YANGState Key Laboratory of Advanced Welding Production Technology, Harbin institute of Technology, Harbin 150001, china State Key Laboratory of Advanced Welding Production Technology Harbin Institute of Technology Harbin 150001 China

The interaction between Zn-AI eutectic alloy and Al203p/6061AI composites in the vacuum furnace was investigated. Great attention has been paid to the elements diffusion, the microstructure and formation of the interface between Zn-AI eutectic alloy and Al2O3p/6061AI composites. Experimental results show that Zn-AI eutectic alloy has a good wetting ability to Al2O3p/6061 Al composites and the wetting angle decreases with increasing the temperature in vacuum. After the interaction, an interaction layer forms between Zn-AI alloy and Al2O3p/6061 Al composites. The phases in the interaction layer mainly consist of α-AI(Zn), Al2O3 and CuZn5 resulted from the diffusion of elements from the Zn-AI alloy. Several porosities distribute in the region near the interface of the Zn-AI alloy/interaction layer. The amount of shrinkage voids in the interacting layer is relevant to the penetration of Zn element into Al2O3p/6061Al composites which is a function of temperature. So it is necessary to lower heating temperature in order to limit the Zn penetration.

关键词： Al2O3p/6061Al composites Zn-Al eutectic alloy Wetting Interface microstructure

FORMATION OF SOCIAL NORMS IN COMMUNICATING AGENTS WITH COGNITIVE FRAMEWORKS

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Journal of Systems science & Complexity 2001年第1期14卷 54-74页

作者： Takashi Hashimoto (Japan Advanced institute of science and Technology, Tatsunokuchi, Ishikawa, 923-1292, Japan) Susumu Egashira (Otaru University of Commerce, 3-5-21, Midori, Otaru, 047-8501, Japan University of Cambridge) Japan Advanced institute of science and Technology 日本 923-1292 Otaru University of Commerce 日本 047-8501

This article deals with the process of formation of norms in societies in which individuals act according to their own cognitive framework under communication. The individuals acquire information from others and interpret it. The way of individual’s action is revised through changing the source of information and reforming the method of interpretation. Through the revising mechanisms, assemblages sharing cognitive frameworks are established. First individuals adopt the same source of information and then arrange the shared cognitive framework. The assemblages are considered as groups with common norms, since the same cognitive framework gives actions coherency. In the process of formation the two revising mechanisms function in turn. The intensity of interaction among individuals affects the period to build norms and the size of groups sharing the norms. The size develops under strong interaction but the period becomes long. The dependency of the average size of norms on the strength obeys a power law.

关键词： Formation of norms cognitive framework multi-agent model.

Quasi-periodicity of temperature changes on the millennial scale

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Progress in Natural science:Materials International 2003年第8期 43-48页

作者： GE Quansheng, FANG Xiuqi and ZHENG Jingyun (1. Department of Geography, Lanzhou University, Lanzhou 730000, china 2. institute of Geographical science and Resources Research, Chinese Academy of sciences, Beijing 100101, china 3. Department of Geography, Beijing Normal University, Beijing 100875, china)

Quasi-periodicity of temperature changes on the millennial scale is found according to the proxy data both from historicaldocuments and natural evidence in china. The auto-correlation of the temperature changes series for the last 2000 years is most significanton the 1350 a time lag. The period of 1350 a includes 4 warm/cold stages: 200～250 a warm stage, 150～200 a cold stage, 300～350 awarm stage, and 550～600 a cold stage. In contrast to the 550～600 a cold stage, the other three stages can be united in one warm domi-nant stage. Inferred from the 1350 a period, the 20th century warm stage belongs to the 200～250 a warm stage, which is similar to thewarm stage occurring during the 570's～770's. The process of temperature change in the 20th century warm stage is similar to that ofthe 570's～770's. But the warming rate in the 20th century is more rapid. The temperature anomaly in the 1980's～1990's shows agreater departure from the regression equation of that between 1500' s～1900's and 150's～650' s. W

关键词： quasi-periodicity temperature change millennial scale the period of 1350a.

ALL ADMISSIBLE LINEAR ESTIMATES OF REGRESSION COEFFICIENTS UNDER MATRIX LOSS

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Systems science and Mathematical sciences 1989年第1期2卷 80-91页

作者：吴启光陈建宝 institute of Systems science Academia SinicaBeijingChina

The necessary and sufficient conditions for a linear estimator of a linear estimable functionof regression coefficients in a general fixed effects linear model with the assumptions of normality to beadmissible in the class of all estimators under matrix liss function are *** a general randomeffects or mixted effects linear model the necessary and sufficient conditions are obtained too.

关键词： Admissibility matrix loss function linear model regression cofficients linear estimator

Study on the wear behaviour of plain bearing materials in oil pumps for transmitting dead oil or lubricating oil

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science china Mathematics 2001年第S1期44卷 212-217页

作者： QIN Xiangpei GAO Wanzhen LI Jian Wuhan Research institute of Materials Protection, Wuhan 430030, china Wuhan Res Inst Mat Protect Wuhan 430030 Peoples R China

Through the experiment and analysis with five kinds of plain bearing material and twokinds of journal material which were processed to find most suitable couples, it was confirmed that40Cr (through VNS process) for the journal and QSn4-3 for the bearing; and 40Cr (through VNSprocess) for the journal and modified UHMWPE for the bearing are both rational choices. And thesecond one has more advantages than the first one when some abradant exist in the lubricatemedium of dead oil.

关键词： boundary lubrication abrasive wear Plain bearing materials UHMWPE

Expression analysis of gdcsP promoter from C_3-C_4 intermediate plant Flaveria anomala in transgenic rice

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Chinese science Bulletin 2001年第19期46卷 1635-1638,1675页

作者： CHEN Shuai, QU Nan, CAO Shouyun, Hermann Bauwe. CHEN Shouyi, TIAN Wenzhong & CHU Chengcai1. institute of Genetics, Chinese Academy of sciences, Beijing 100101, china 2. institute of Plant Genetics and Crop Plant Research (IPK), 06466 Gatersleben, Germany 3. Rostock University, 18055 Rostock, Germany institute of Genetics Chinese Academy of Sciences Beijing China institute of Plant Genetics and Crop Plant Research (IPK) Gatersleben Germany Rostock University Rostock Germany

The gdcsP promoter isolated from C3-C4 intermediate plant Flaveria anomala was fused to the β-glu-curonidase (GUS) gene. The chimeric gene was inserted into the binary vector pBin19 and introduced into the rice (Oryza saliva L.) cv. 8706 by Agrobacterium-mediated gene transfer. GUS activity can be detected in leaf, leaf sheath, stem and root tissues via fluorometric GUS assay. However, no GUS activity was found in mature endosperm. Histochemical localization revealed that GUS expression was exclusively restricted to vascular tissues in transgenic plants. This promoter also showed spatial-temporal expression patterns that GUS expression declined significantly with the maturity of plants. These expression patterns make the gdcsP promoter extremely valuable in the applied biotechnology that needs target gene expression restricted to vascular tissues.

关键词： rice (Oryza sativa L.) glycine decarboxyla.se P-protein subunit vascular tissue.

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水平轴风力机状态空间模型参数辨识

太阳能学报 2003年第3期24卷 371-375页

作者：包能胜叶枝全汕头大学能源科学研究所汕头515063

讨论了水平轴风力机系统在状态空间模型条件下的参数辨识。首先 ,根据风力机机理并基于一定的假设条件 ,推导出风力机的机理模型 ,通过线性化得到系统在某一工况点附近的状态方程。其次 ,利用辨识实验测试系统的输入输出数据 ,采用预报... 详细信息

讨论了水平轴风力机系统在状态空间模型条件下的参数辨识。首先 ,根据风力机机理并基于一定的假设条件 ,推导出风力机的机理模型 ,通过线性化得到系统在某一工况点附近的状态方程。其次 ,利用辨识实验测试系统的输入输出数据 ,采用预报误差法 ,得到系统多输入多输出的随机模型。最后 ,对所得到的随机模型进行了分析与检验 ,讨论了辨识模型与机理模型的优缺点。

关键词：水平轴风力机参数辨识预报误差法状态空间模型

New progress of lake sediments and environmental changes research in china

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Chinese science Bulletin 1999年第19期44卷 1744-1754页

作者： WANG Sumin and ZHANG ZhenkeLaboratory of Lake Sediment and Environment, Nanjing institute of Geography and Limnology, Chinese Academy of sciences , Nanjing 210008, china Department of Geography and Oceanology, Nanjing University , Nanjing 210093 , china Laboratory of Lake Sediment and Environment Nanjing Institute of Geography and Limnology Chinese Academy of Sciences Nanjing China Department of Geography and Oceanology Nanjing University Nanjing China

Environmental change recorded by lake sediments is one of the important branches of the past global changes study. The new progress of lake sediments and environmental changes in china since the late 1980s has been comprehensively discussed. The highlights emphasized are Asian paleomonsoon migration reflected by lake level fluctuation, uplift of the Qinghai-Xizang Plateau recorded by lacustrine sediments, saltlake sediments and

关键词： lake sediments environmental change.