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The age of the plant fossil assemblage in the Liuqu Conglomerate of southern Tibet and its tectonic significance

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Progress in Natural Science:Materials International 2006年第1期16卷 55-64页

作者： FANG Aimin1, YAN Zhen1, LIU Xiaohan2. PAN Yusheng1, LI Jiliang1, YU Liangjun1, HUANG Feixing2.and TAO Junrong3.(1.Laboratory of Lithosphere Tectonic Evolution, institute of Geology and Geophysics,{3., {2. 10002., China 2. institute of Tibet Plateau Research,{3., {2. 100085, China 3. institute of Botany, chinese A cademy of sciences, {2. 100093. China) Laboratory of Lithosphere Tectonic Evolution Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China institute of Tibet Plateau Research Chinese Academy of Sciences Beijing 100085 China institute of Botany Chinese Academy of Sciences Beijing 100093 China)

The Liuqu Conglomerate, situated to the south of Yarlung Tsangbo Suture Zone (YTSZ), is a suit of molasse formed in a foreland basin of the Himalayan orogenic belt after the collision between the two plates of the Indian and Eurasion, It is of great significance in constraining the younger limit time of the collision of the two plates and providing stratigraphic evidence to reveal the post-colli sional tectonic evolution and uplifting history of the Tibet plateau. However, the age of this molasse suit and its correlation to other synchronous strata distributed in southern Tibet have been in great disputes for a long time. Especially in recent years, argues on its ages are growing violently with the recognition of the great sedimentary tectonic significances of this molasse. During the field work carried out recently on this molasse suit, a lot of plant fossils were found preserved in fairly good conditions in the upper part of this strata, which is of great help in determining its age. By identification, the assemblage of the plant fossils belongs to a tropic to subtropic flora developed in the southern margin of the Northern Hemisphere supercontinent during the Middle to Later Eocene, which can provide good constraint on its formation age. This paper is to give a brief introduction of the plant assemblage and its age, and to discuss their tectonic significances.

关键词： Liuqu conglomerate plant fossils age Eocene Tectonic implications.

A nontrivial product in the stable homotopy groups of spheres

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Science China mathematics 2004年第6期47卷 831-841页

作者： LIU Xiuguiinstitute of mathematics,{2.,{3., China institute of mathematics Chinese Academy of Sciences Beijing China

Let A be the mod p Steenrod algebra for p an arbitrary odd prime. In 1962. Liulevicius described h i and b k in Ext* A ’*(Zp,Zp) having bigrading (1, sui— 1) and (2. 2. k+1 x(p— 1)), respectively. In this paper we prove that for p ≥ 7, n ≥ 4 and $3.\leqslant s 3.p^n q + sp^2.q + (s - 1)pq + (s - 1)q + s - 3. (Z_p ,Z_p )$ survives to E∞ in the Adams spectral sequence, where q = 2.p — 1).

关键词： stable homotopy groups of spheres Adams spectral sequence Toda-Smith spectra May spectral sequence

Spectral analysis of quasi-stationary sea surface topography from GRACE mission

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Science China Earth sciences 2005年第11期48卷 2040-2048页

作者： ZHANG Zizhan1,2.& LU Yang1,3.1. institute of Geodesy and Geophysics, chinese academy of sciences, Wuhan 43.077, China 2. Graduate School of the chinese academy of sciences, {3. 10003., China 3. Unite Center for Astro-geodymics Research, chinese academy of sciences, Shanghai 2.003., China institute of Geodesy and Geophysics Chinese Academy of Sciences Wuhan China Graduate School of the chinese academy of sciences Beijing China Unite Center for Astro-geodymics Research Chinese Academy of Sciences Shanghai China

During the last two decades satellite altimetry has offered an abundance of meas-urements of the sea surface resulting in the improvement of global mean sea surface height (MSSH) and marine geoid determination. On the other hand, with the launching of new genera-tion gravity satellites, some high accuracy long-wavelength gravity models are available. These breakthroughs give us a great opportunity for new estimation of quasi-stationary sea surface topography (QSST). In this paper, the new gravity model GGM01C derived from GRACE mission is briefly presented, and a new global high precision and high-resolution QSST is determined based on the GGM01C model and the global MSSH. The spectral features of the QSST esti-mated by GGM01C and EGM96 gravity model to degree/order 2.0 are discussed by spectral analysis. As a result, the QSST is mainly composed of long waves, medium waves partially and short waves scarcely, its power spectral structures are different between the zonal direction and the meridional direction, there are great differences between the two models, which maybe ex-plain why the ocean currents derived from the two gravity models by Tapley show different pat-terns.

关键词： quasi-stationary sea surface topography, mean sea surface height, GGM01, fast Fourier transform, spectral analysis

Some Performance Measures of Transfer Line Consisting of Two Unreliable Machines with Reprocess Rule

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Systems Science and Systems Engineering 1998年第3期8卷 27-36页

作者： LI Wei CAO Jinhua institute of applied {2.,{3.,beijing 100080

In this paper, we consider a transfer line with two unreliable machines and a single storage buffer, in which the second machine’s processing time and repair time have general distributions, and a piece processed by machine i will be reprocessed with probability q i (i=1, 2. because of uncompletely or not very well processed just before. At first, the exactly results of the reprocessed rate, the output rate and the blocked probability of machine 1, the reprocessed rate and the starved probability of machine 2. and the production rate of the system, are obtained when the first machine is reliable. And then, some approximating results of above indices are given when two machines are both unreliable.

关键词： transfer line reprocess rule blocked probability production rate.

The gravity wave instability induced by photochemistry in summer polar mesopause region

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chinese Science Bulletin 2000年第3期45卷 267-272页

作者： Center for Space Science and applied Research, chinese academy of sciences,{2., China Laboratory of Numeric Study of Heliospheric Physics, chinese academy of sciences,{2., China Center for Space Science and applied Research Chinese Academy of Sciences Beijing China Laboratory of Numeric Study of Heliospheric Physics Chinese Academy of Sciences Beijing China

The effect of diabatic process due to the photochemical heating and cooling on the gravity wave propagation in middle atmosphere is studied. A linear gravity wave model which considers the diabatic process is established. The unstable region and the growth rate of the gravity wave caused by photochemistry are calculated. And the comparison between the model and the adiabatic gravity wave theory of pure dynamics is made. The results indicate that the photochemical heating process can induce the instability of gravity wave at mesopause. The intensity of the instability becomes stronger as the temperature decreases. The temperature feature and the altitude characteristics of the instability are consistent with the observation. Therefore, the instability of the gravity wave induced by photochemistry may be an important mechanism in polar mesopause region in summer.

关键词： photochemistry instability gravity wave growth rate.

Energy functionals and killing transform

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chinese Science Bulletin 1997年第19期42卷 1593-1596页

作者： YING JiangangDepartment of mathematics, Zhejiang University, Hangzhou 3.002., China Istitute of applied mathematics, chinese academy of sciences, beijing 100080, China Department of mathematics Zhejiang University Hangzhou China Istitute of applied mathematics Chinese Academy of Sciences Beijing China

LET X=（Xt,Px） be a right Markov process with state space （E,ε）, semigroup （P1） andresolvent （Uq）. As in ref.[1, 2., we denote by Excq（X ）, Disq（X） and Conq（X） thecones of excessive, dissipative, conservative measures of X, respectively, and by Sq（X） thecone of excessive functions of X. By convention we drop the superscript q when it is zero. LetMF be the set of all exact multiplicative functional of X. For any given M∈MF, writeEM:= {x∈E:PM0 = 1 = 1} and SM: = inf} t>0: M1= 0 } for the set of

关键词： right processes multiplicative functionals Revuz measures energy functional capacity.

A tentative study for the prediction of the CME related geomagnetic storm intensity and its transit time

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Science China(Technological sciences) 2005年第6期48卷 648-668页

作者： ZHAO Xinhua1,2.& FENG Xueshang1,3.1. SIGMA Weather Group, Key Laboratory of Space Weather, Center for Space Science and applied Re-search, chinese academy of sciences,{2., China 2. Graduate School of the chinese academy of sciences, beijing 10003., China 3. School of Geophysics and Geoinformation Systems, China University of Geosciences, beijing 100083. China SIGMA Weather Group Key Laboratory of Space Weather Center for Space Science and Applied Research Chinese Academy of Sciences Beijing China Graduate School of the chinese academy of sciences Beijing China School of Geophysics and Geoinformation Systems China University of Geosciences Beijing China

Using 80 CME-ICME events during 1997.1―2.02.9, based on the eruptive source locations of CMEs and solar magnetic field observation at the photosphere, a current sheet magnetic coordinate (CMC) system is established in order to study the propagation of CME and its geoeffectiveness. In context of this coordinate system, the effect of the eruptive source location and the form of heliospheric current sheet (HCS) at the eruptive time of CME on the geomagnetic storm intensity caused by CME and the CME’s transit time at the Earth is investigated in detail. Our preliminary conclusions are: 1) The geomagnetic disturbances caused by CMEs tend to have the so-called “same side-opposite side effect”, i.e. CMEs erupt from the same side of the HCS as the earth would be more likely to arrive at the earth and the geomagnetic disturbances associated with them tend to be of larger magnitude, while CMEs erupting from the opposite side would arrive at the earth with less probability and the corresponding geomagnetic disturbance magnitudes would be relatively weaker. 2. The angular separation between the earth and the HCS affect the corresponding disturbance intensity. That is, when our earth is located near the HCS, adverse space weather events occur most probably. 3. The erupting location of the CME and its nearby form of HCS will also affect its arrival time at the earth. According to these conclusions, in this context of CMC coordinate we arrive at new prediction method for estimating the geomagnetic storm intensity (Dstmin) caused by CMEs and their transit times. The application of the empirical model for 80 CME-ICME events shows that the relative error of Dst is within 3.% for 59% events with Dstmin≤?50 nT, while the averaged absolute error of transit time is lower than 10 h for all events.

关键词： coronal mass ejections, current sheet magnetic coordinate system, geomagnetic storm intensity, transit time, prediction method.

PARALLEL CHAOTIC MULTISPLITTING ITERATIVE METHODS FOR THE LARGE SPARSE LINEAR COMPLEMENTARITY PROBLEM

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Journal of Computational mathematics 2001年第3期19卷 281-292页

作者： Zhong-zhi Bai (State Key Laboratory of Scientific/Engineering Competing institute of Computational mathematics and Scientific/Engineering Computing, {2. of mathematics and Systems sciences, chinese academy of sciences, beijing 100080, China) 中科院计算数学与工程计算数学所科学与工程计算国家重点实验室北京 100080

Focuses on a study which presented a parallel chaotic multisplitting method for solving the large sparse linear complementarity problem. Preliminaries of the study; Equations of the parallel chaotic multisplitting met... 详细信息

关键词： linear complementarity problem matrix multisplitting chaotic iteration relaxed method convergence property

Formal Verification under Unknown Constraints

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Wuhan University Journal of Natural sciences 2005年第1期10卷 43-46页

作者： LI Guang-hui 1,2.3., LI Xiao-wei 2.3.. School of Information Engineering, Zhejiang Forestry College, Hangzhou 3.13.0, Zhejiang, China 2. {3. of Computing Technology, chinese academy of sciences,{2., China 3. Graduate School of the chinese academy of sciences, beijing 10003., China School of Information Engineering Zhejiang Forestry College Hangzhou Zhejiang China institute of Computing Technology Chinese Academy of Sciences Beijing China Graduate School of the chinese academy of sciences Beijing China

We present a formal method of verifying designs with unknown constraints (e.g., black boxes) using Boolean satisfiability (SAT). This method is based on a new encoding scheme of unknown constraints, and solves the corresponding conjunctive normal form (CNF) ***,this method can avoid the potential memory explosion, which the binary decision diagram (BDD) based techniques maybe suffer from, thus it has the capacity of verifying large designs. Experimental results demonstrate the efficiency and feasibility of the proposed method.

关键词： formal verification unknown constraints black box Boolean satisfiability Boolean comparison