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Origin, Evolution and Mechanism of the Jehol Fauna

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Acta Geologica Sinica(English Edition) 1991年第2期65卷 203-215页

作者： Wang Si’en institute of geology, chinese academy of Geological sciences, beijing Liu Linqun institute of geology Chinese Academy of Geological Sciences Beijing

This paper deals with the geographic distribution and geological setting of the Jehol (northeastHebei-southwest Liaoning-southeast Inner Mongolia) fauna, and discusses the origination and the evolution ofits major biological groups. It is demonstrated that the Yan-Liao (northern Hebei-western Liaoning) area is theprovenance for the fauna. Why the fauna originated and developed in the area was intimately related to suchfactors as the palaeoclimate, palaeogeography, crustal movement, volcanism and frequent reversals of magnet-ic polarity at that time, in addition to the internal factors of the organisms themselves.

关键词： Origin Evolution and Mechanism of the Jehol Fauna

DMTB:A comprehensive online resource of 16S rRNA genes,ecological metadata,oligonucleotides,and magnetic properties of magnetotactic bacteria

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chinese science Bulletin 2011年第6期56卷 476-478页

作者： LIN Wei1,2, LI Bi1,2 & PAN YongXin1,2 1 Paleomagnetism and Geochronology Laboratory, Key Laboratory of the Earth’s Deep Interior, institute of geology and geophysics, chinese academy of sciences, beijing 10002., china 2 France-china Bio-Mineralization and Nano-Structures Laboratory, institute of geology and geophysics, chinese academy of sciences, beijing 10002., china Paleomagnetism and Geochronology Laboratory Key Laboratory of the Earth"s Deep Interior Institute of Geology and Geophysics Chinese Academy of Sciences France-china Bio-Mineralization and Nano-Structures Laboratory Institute of Geology and Geophysics

Magnetotactic bacteria (MTB) are of interest in microbiology, biomineralization, advanced magnetic materials, and bio-geo-sciences because of their ability to form highly ordered intracellular magnetic minerals. Great strides for MTB studies have been made in the past four decades. In this paper we complied the first internet-accessible database for MTB, Database of Magnestotactic Bacteria (DMTB). It contains information of 16S rRNA gene sequences, corresponding ecological metadata, oligonucleotides, and magnetic properties of MTB. The comprehensive information contained in DMTB will provide a very useful data resource for researchers from different disciplines. The website of DMTB is at http://***/.

关键词： rRNA基因序列趋磁细菌 16S 网上资源寡核苷酸磁学性质生态磁性材料

Liaoxiornis delicatus *** ***.,the smallest Mesozoic bird

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chinese science Bulletin 1999年第9期44卷 834-838页

作者： HOU Lianhai and CHEN Peiji institute of Vertebrate Paleontology and Paleoanthropology, chinese academy of sciences , beijing 100044, china Nanjing institute of geology and Paleontology, chinese academy of sciences , china institute of Vertebra Paleontology und Paleoanthropology Chinese Academy of Sciences Beijing China Nanjing Instittue of Gology and Paleontology Chinese Academy of Sciences China

Recently, a very small and complete bird specimen was collected from the Confuciusornis-bearing Yixian Formation. This finding represents a new kind of Mesozoic bird, named Liaoxiornis delicatus. It is characterized by a short skull with teeth, a long neck and a very small sternum with only posterior process; the humeral head is not internally curved, and the hindlimbs are longer than the forelimbs. Liaoxiomis delicatus is not only much smaller than Confuciusornis, but also smaller than Cathayomis and other early Cretaceous birds. It is the smallest bird known from Mesozoic deposit. Liaoxiornis provides new evidence indicating that the early adaptive radiation of birds is complicated.

关键词： Mesozoic early bird evolution of birds.

NONPARAMETRIC APPROACH TO IDENTIFYING NARX SYSTEMS

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Journal of Systems science & Complexity 2010年第1期23卷 3-21页

作者： Qijiang SONG·Han-Pu CHEN Key Laboratory of Systems and Control,institute of Systems science,academy of Mathematics and Systems science,chinese academy of sciences,beijing 100190,china Key Laboratory of Systems and Control Institute of Systems Science Academy of Mathematics and Systems Science Chinese Academy of Sciences

This paper considers identification of the nonlinear autoregression with exogenous inputs(NARX system).The growth rate of the nonlinear function is required be not faster than linear withslope less than *** value of f(·) at any fixed point is recursively estimated by the stochasticapproximation (SA) algorithm with the help of kernel *** consistency of the estimatesis established under reasonable conditions,which,in particular,imply stability of the *** simulation is consistent with the theoretical analysis.

关键词： α-mixing geometrically ergodic Markov chains NARX nonparametric recursive estimate stochastic approximation strongly consistent.

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A01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 chinese Acad Sci Xinjiang Inst Ecol & Geog Urumqi 830011 Peoples R China chinese Acad Sci Inst Geog Sci & Nat Resources Res Beijing 100101 Peoples R China chinese Acad Sci Grad Sch Beijing 100039 Peoples R 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

Vermiform trace fossils from the Precambrian Ruyang Group, western Henan

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chinese science Bulletin 1997年第3期42卷 251-254页

作者： HU Jianmin, MENG Qingren and LI Wenhou1 Xi’ an College of geology, Xi’an 710054, china 2. institute of geophysics, chinese academy of sciences, beijing 100101, china 3 Department of geology, Northwest University, Xi’an 710069, china Xi’an College of geology Xi’an China institute of geophysics Chinese Academy of Sciences Beijing China Department of geology Northwest University Xi’an China

THE origin and evolution of Precambrian lives has been a long-standing controversial problem. It is now generally accepted by most paleontologists that the origin of metazoa can be traced back to more than 1000 Ma, because the Ediacara and latest pre-Ediacara fauna, such as the Huainan fauna, are featured by their diversification of forms, complicated structures

关键词： Precambrian trace fossil Ruyang Group.

Effects of the Biot and the squirt-flow coupling interaction on anisotropic elastic waves

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chinese science Bulletin 2000年第23期45卷 2130-2138页

作者： YANG Dinghui & ZHANG Zhongjie Department of Mathematical sciences, Tsinghua University, beijing 100084, china institute of geophysics, chinese academy of sciences, beijing 100101, china Department of Mathematical sciences Tsinghua University Beijing China institute of geophysics Chinese Academy of Sciences Beijing China

Considering the velocity anisotropy of the solid/fluid relative motion and employment of the BISQ theory based on the one-dimensional porous isotropic case, we establish a two-phase anisotropic elastic wave equation to simultaneously include the Biot and the squirt mechanisms in terms of both the basic principles of the fluid’s mass conservation and the elastic-wave dynamical equations in the two-phase anisotropic rock. Numerical results, while the Biot-flow and the squirt-flow effects are simultaneously considered in the transversely isotropic (Tl) poroelastic medium, show that the attenuation of the quasi P-wave and the quasi SV-wave strongly depend on the permeability anisotropy, and the attenuation behavior at low and high frequencies is contrary. Meanwhile, the attenuation and dispersion of the quasi P-wave are also affected seriously by the anisotropic solid/fluid coupling additional density.

关键词： two-phase anisotropy Biot flow squirt-flow elastic wave attenuation and dispersion BISQ model.

Poisson kernel and Cauchy formula of a non-symmetric transitive domain

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science china Mathematics 2010年第7期53卷 1678-1683页

作者： LU Qi-Keng institute of Mathematics, academy of Mathematics and System science, chinese academy of sciences, beijing 100190, china 1. institute of Mathematics Academy of Mathematics and System Science Chinese Academy of Sciences Beijing 100190 China

In 1965, Lu Yu-Qian discovered that the Poisson kernel of the homogenous domain S m,p,q={Z∈Cm×m, Z1∈Cm×p,Z2 ∈Cq×m|2i1( Z-Z+)-Z1Z1′-Z2′Z2>0} does not satisfy the Laplace-Beltrami equation associated with the Bergman metric when S m,p,q is not symmetric. However the map T0:Z→Z, Z1→Z1 , Z2→Z2 transforms S m,p,q into a domain S I (m, m + p + q) which can be mapped by the Cayley transformation into the classical domains R I (m, m + p + q). The pull back of the Bergman metric of R I (m, m + p + q) to S m,p,q is a Riemann metric ds 2 which is not a Khler metric and even not a Hermitian metric in general. It is proved that the Laplace-Beltrami operator associated with the metric ds 2 when it acts on the Poisson kernel of S m,p,q equals 0. Consequently, the Cauchy formula of S m,p,q can be obtained from the Poisson formula.

关键词： Poisson kernel Cauchy formula

Models and methods for precise determination of ionospheric delay using GPS

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Progress in Natural science:Materials International 2007年第2期17卷 187-196页

作者： YUAN Yunbin, HUO Xingliang and OU Jikun ( institute of Geodesy and geophysics, chinese academy of sciences, Wuhan 430077, china Graduate University of chinese A-cademy of sciences, beijing 100039, china) [a]chinese academy of sciences Institute of Geodesy and Geophysics Wuhan China [b]Graduate University of chinese academy of sciences Beijing China

The basic principles and methods for precisely determining ionospheric delays in GPS observations are introduced and discussed. Various methods and models for fitting ionospheric delays based on GPS are compared and a... 详细信息

关键词： GPS ionospheric delay atmosphere modeling precise GPS positioning.