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Science china(Technological Sciences) 2010年第12期53卷 3264-3274页

作者： XU Meng1 & GAO ZiYou2 1 MOE Key Laboratory for Urban Transportation Complex Systems Theory and Technology, Beijing Jiaotong University, Beijing 100044, china 2 Institute of Systems Science, School of Traffic and Transportation, Beijing Jiaotong University, Beijing 100044, china MOE Key Laboratory for Urban Transportation Complex Systems Theory and Technology Beijing Jiaotong University Institute of Systems Science School of Traffic and Transportation Beijing Jiaotong University

This paper is concerned with the algorithm of the supply chain network equilibrium model and its equivalent supernetwork based traffic network equilibrium model with elastic demands. Both models are further written as nonlinear complementarity problems. Semismooth least squares reformulations of the complementarity problems are presented and their convergence properties are investigated. Considering the drawbacks of Quasi-Newton method (using the Fischer-Burmeister function), a semi-smooth Levenberg-Marquardt-type method is proposed to solve the problems. Numerical examples show that the Levenberg-Marquardt-type method can solve the supply chain network equilibrium model and its equivalent supernetwork based traffic network equilibrium model significantly, and is more efficient than the Quasi Newton method and the modified projection method. Furthermore, the Levenberg-Marquardt-type method with the equivalent supernetwork based complementarity formulation can be implemented faster than with the supply chain network equilibrium complementarity formulation.

关键词： supply chain networks traffic network equilibrium supernetwork nonlinear complementarity problem Levenberg Marquardt-type method

Use-wear evidence confirms the earliest hafted chipped-stone adzes of Upper Palaeolithic in northern china

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Chinese Science Bulletin 2010年第3期55卷 268-275页

作者： ZHANG XiaoLing1,2,3, SHEN Chen1,2,4 GAO Xing1,2 CHEN FuYou1,2 & WANG ChunXue1,2,3 1Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijing 100044, china 2Laboratory of Human Evolution and Archaeometry, Chinese Academy of Sciences, Beijing 100044, china 3Graduate University of Chinese Academy of Sciences, Beijing 100049, china 4The Royal Ontario Museum, Toronto M5S 2C6, Canada Institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences Beijing 100044 China Laboratory of Human Evolution and Archaeometry Chinese Academy of Sciences Beijing 100044 China Graduate University of Chinese Academy of Sciences Beijing 100049 China Royal Ontario Museum Toronto M5S 2C6 Canada

Chipped-stone "adze-shaped objects" (ASOs) were identified from a few Upper Palaeolithic sites in northern china. Its morpho- logical form resembles to ground-stone type-specific adze, but the function of the ASO has never been assessed. The objective of this study is to investigate the use function of this particular tool type recovered from the Hutouliang site in the Nihewan Basin of northern china. In this study, the lithic use-wear analysis is applied to examining microscopically edge-damages and sur- face-rounding of the tools in order to assess how they were employed. The result suggests that the ASO might have been used as woodworking tools with a hafted shaft, providing evidence for the appearance of the earliest hafted chipped-stone adzes prior to 10000 years ago in northern china. This study also demonstrates that the use-wear technique is an innovated and effective analytic appraoch to the study of stone tool functions that has been conventionally treated by typo-technological analyses. Stone tool use-patterns revealed by use-wear evidence would shed new insights on prehistoric adaptive strategies of modern human in northern china.

关键词：旧石器时代晚期中国北方磨损证据石材加工工具木工工具中国网站技术分析

Reconstructing mean maximum temperature of growing season from the maximum density of the Schrenk Spruce in Yili,Xinjiang,china

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Chinese Science Bulletin 2009年第13期54卷 2300-2308页

To study the historical temperature variation in Yili of Xinjiang,the tree-ring chronologies of maximum density(MXD) and tree-ring width(TRW) were established with the Schrenk Spruce(Picea schrenkiana *** Mey) collected from six sites to analyze the characteristics and ability of response to climate *** results suggest that the MXD chronology of the Schrenk Spruce from different sampling sites responded to climate change well and were positively correlated with the mean maximum temperature and the mean temperature from April to August in the study *** mean maximum temperature anomaly from April to August,spanning the years from 1848 to 2000,was reconstructed by three MXD chronologies which were selected by stepwise *** reconstructed function was stable and explained 56.2% of the *** reconstructed results indicated a cold span of 153 years in spring and summer from the beginning of the 1950s to the beginning of the 1970s in the Yili *** strongly increasing tendency was detected in the mean maximum temperature anomaly from April to August during this reconstructed period.

关键词：平均最高气温伊犁谷地最大密度云杉胡杨生长季节新疆树木年轮宽度

Growth characteristics and response to climate change of Larix Miller tree-ring in china

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Science china Earth Sciences 2010年第6期53卷 871-879页

As one of the earliest species used in dendrochronological studies, Larix responds sensitively to climate change. In this study, nine larch species and one variety from eleven sites were collected to study the growth characteristics of tree-ring width using dendrochronological methods. Ten residual tree-ring chronologies were developed to analyze their relationships with regional standardized anomaly series by Pearson’s correlation analysis. The results suggest that most of the chronologies had significantly positive correlations with the mean temperature and mean maximum temperature in May. The spring temperature evidently limited the radial growth of the larch species without precipitation control. The largest mean tree-ring width was found in Himalayan Larch in Jilong, whereas Master Larch in Si’er reflected the smallest mean value. Both species presented little climate information in this study. Chinese, Potanin, and Tibetan larches are significantly correlated with climate change, implying a huge potential for climate history reconstruction. The elevation of the sampling sites appears to be an important condition for tree-ring growth of larches responding to climate factors.

关键词： Larix Miller tree-ring climate change mean temperature in May

Aepyosciurinae——a new subfamily of Sciuridae(Rodentia,Mammalia)from basal loess deposits at the northeastern border of Tibetan Plateau

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Chinese Science Bulletin 2003年第7期48卷 691-695页

作者： WANG Banyue & QIU Zhanxiang Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijing 100044, china Chinese Academy of Sciences

Aepyosciurinae, a new subfamily of Sciuridae, were found at the base of the early Pleistocene loess deposits in Dongxiang County, Gansu Province. Its unilaterally hyp-sodont and lophodont cheek teeth are unique among the sciurids so far known all over the world. Certain degree of similarity can be observed between the cheek teeth of the new subfamily and the Anomalurinae living in tropical and subtropical forests in central and western Africa. Aepyosci-uris orientalis gen. et sp. nov. might have lived in montaneous woodland or grassland and lived on harder leaves, barks, or even grass. This tends to show that the northeastern border area of the Tibetan Plateau had been lifted considerably high in early Pleistocene (ca. 2 Ma), with drier climate, becoming a suitable habitat for Aepyosciurus orientalis.

关键词：西藏高原松鼠亚科啮齿目哺乳纲早更新世黄土沉积物古动物分类学

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Progress in Natural Science:Materials International 2005年第12期15卷 1110-1116页

作者： LIU Gang,LI Xin,JIANG Weimei and LI Min Department of Atmospheric Sciences,Nanjing University,Nanjing 210093,china Beijing Municipal Environmental Protection Bureau,Beijing 100044,china Department of Atmospheric Sciences Nanjing University Nanjing 210093 China. Beijing Municipal Environmental Protection Bureau Beijing 100044 China

The S-L (She and Leveque) scaling law,also named the hierarchical similarity theory,has been extensively tested for the turbulence made in the laboratory,but seldom been tested for the turbulence in the atmospheric boundary layer (ABL).In this paper, the S-L scaling law is applied to the turbulence in the ABL observed under unstably stratified conditions and over different types of underlying *** results of analyses show that over this type of homogeneous and flat underlying surface,such as the underlying surface in HUBEX (Huaihe River Basin Energy and Water Cycle Experiment),vertical speed and temperature fields well satisfy the S-L scaling *** the turbulence over the homogeneous but rather rough underlying surface of forest and under unstably stratified conditions in PFRD (Park Falls Ranger District of the Chequamegon National Forest,Wisconsin,USA),the analyses show that the vertical speed and temperature fields sometimes conform sometimes do not conform to the S-L scaling ***,at a time,either both of the vertical speed and temperature fields conform to the S-L scaling law,or both of them do *** speed fields in both of the field experiments do not satisfy the S-L scaling *** new explanation of the above-mentioned phenomena is given.

关键词： atmospheric turbulence Reynolds number S-L scaling law in the atmospheric turbulence boundary layer processes nonlinear dynamics

NEW APPROACHES TO THE GRAPHICNESS OF A MATROID

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Systems Science and Mathematical Sciences 1999年第S1期12卷 31-42页

作者： LIU Yanpei(Institute of Mathematics, Northern Jiaotong University, Beijing 100044 china)

This article provides some new characterizations for testing if a matroid isgraphic. One of them can be seen as a consequence deduced from the Wu’s theory on theplanarity of graphs.

关键词： Matroid graphicness basic order.

Performances of carbon nanotube field effect transistors with altered channel length

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Science china(Technological Sciences) 2010年第1期53卷 253-256页

作者： FENG Ying,HUANG ShiHua,KANG Kai & FENG YuGuang Institute of Optoelectronic Technology,Beijing Jiaotong University,Beijing 100044,china Institute of Optoelectronic Technology Beijing Jiaotong University

The influence of channel length on the performances of carbon nanotube field effect transistors(CNT-FETs) has been *** oxide etching was used to remove approximately a 60 nm layer from the original 100 nm silicon dioxide layer,to thin the dielectric layer of the back *** length of the CNT-FETs was changed along with the etching *** dependence of drain-source current on gate voltage was measured to analyze the performance of the CNT-FETs,including the transconductance,carrier mobility,current ON/OFF ratio,*** results indicate that the devices still keep good quality.

关键词： carbon nanotube field effect transistors mobility buffered oxide etching

A geometrical and physical nonlinear finite element model for spatial thin-walled beams with arbitrary section

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Science china(Technological Sciences) 2010年第3期53卷 829-838页

作者： YANG QingShan 1 &WANG XiaoFeng 2 1 School of Civil Engineering,Beijing Jiaotong University,Beijing 100044,china 2 College of Civil Engineering,Tongji University,Shanghai 200092,china School of Civil Engineering Beijing Jiaotong University College of Civil Engineering Tongji University

Based on the theories of Bernoulli-Euler beams and Vlasov's thin-walled members,a new geometrical and physical nonlinear beam element model is developed by applying an interior node in the element and independent interpolations on bending angles and warp,in which factors such as traverse shear deformation,torsional shear deformation and their coupling,coupling of flexure and torsion,and second shear stress are all ***,geometrical nonlinear strain in total Lagarange(TL) and the corresponding stiffness matrix are *** plastic model is applied to physical nonlinearity to comply with the yield rule of Von Mises and incremental relationship of *** stiffness matrix is derived by numerical integration on the basis of the finite segment *** show that the developed model is feasible in analysis of thin-walled structures with high accuracy.

关键词： Spatial beams thin-walled structures geometrical and physical nonlinearity finite element arbitrary section

Optimization model and algorithm for mixed traffic of urban road network with flow interference

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Science china(Technological Sciences) 2008年第12期51卷 2213-2222页

作者： SI BingFeng,LONG JianCeng & GAO ZiYou State Key Laboratory of Rail Traffic Control and Safety,Beijing Jiaotong University,Beijing 100044,china State Key Laboratory of Rail Traffic Control and Safety Beijing Jiaotong University

In this paper,the problem of interferences between motors and non-motors in urban road mixed traffic network is considered and the corresponding link impedance function is presented based on travel *** the base of this,the main factors that influence travelers' traffic choices are all considered and a combined model including flow-split and assignment problem is *** a bilevel model with its algorithm for system optimization of urban road mixed traffic network is *** the application of the model and its algorithm is illus-trated with a numerical example.

关键词： mixed traffic impedance function user equilibrium optimization