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A three-dimensional variational ocean data assimilation system:Scheme and preliminary results

Science China Earth Sciences 2006年第11期49卷 1212-1222页

作者： ZHU Jiang1,2, ZHOU Guangqing1, YAN Changxiang1, FU Weiwei1 & YOU Xiaobao1,3.1. International Center for Climate and Environment Sciences, institute of Atmospheric Physics, Chinese Academy of Sciences, beijing 100029, China 2. Jiangsu Key Laboratory of Meteorological Disaster, Nanjing University of Information Science and Technology, Nanjing 21004., China 3. beijing institute of applied meteorology, beijing 100029, China International Center for Climate and Environment Sciences Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China Jiangsu Key Laboratory of Meteorological Disaster Nanjing University of Information Science and Technology Nanjing China beijing institute of applied {3. Beijing China

A new 3.VAR-based Ocean Variational Analysis System (OVALS) is developed. OVALS is capable of assimilating in situ sea water temperature and salinity observations and satellite altimetry data. As a component of OVALS, a new variational scheme is proposed to assimilate the sea surface height data. This scheme considers both the vertical correlation of background errors and the nonlinear temperature-salinity relationship which is derived from the generalization of the linear balance constraints to the nonlinear in the 3.VAR. By this scheme, the model temperature and salinity fields are directly adjusted from the altimetry data. Additionally, OVALS can assimilate the temperature and salinity profiles from the ARGO floats which have been implemented in recent years and some temperature and salinity data such as from expendable bathythermograph, moored ocean buoys, etc. A 21-year assimilation experiment is carried out by using OVALS and the Tropical Pacific circulation model. The results show that the assimilation system may effectively improve the estimations of temperature and salinity by assimilating all kinds of observations. Moreover, the root mean square errors of temperature and salinity in the upper depth less than 4.0 m reach 0.63. and 0.3. psu.

关键词： data assimilation, 3.VAR, sea surface height, ARGO floats.

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Progress and review of the studies on the end-Triassic mass extinction event

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Science China Earth Sciences 2005年第12期48卷 2049-2060页

作者： DENG Shenghui1,2, LU Yuanzheng1,2,3.& XU Daoyi4.1. Research institute of Petroleum Exploration and Development, beijing 100083. China 2. Key Laboratory of Oil and Gas Reservoir of PetroChina, beijing 100083. China 3. China University of Geosciences, beijing 100083. China 4. institute of Geology, China Earthquake Administration, beijing 100029, China Research institute of Petroleum Exploration and Development Beijing China Key Laboratory of Oil and Gas Reservoir of PetroChina Beijing China China University of Geosciences Beijing China institute of Geology China Earthquake Administration Beijing China

The mass extinction at the end-Triassic is one of the five biggest in the Phanerozoic. However,it is the least well understood among these five events, and only till last decade it became a great academic interesting subject to geologists. The evidences for this event come obviously from bivalves, brachiopods, ammonites, corals, radiolaria, ostracods and foraminifera of marine habitats, and plants and tetrapods of terrestrial realm. By contrast, for some of other groups, such as marine gastropods and marine vertebrates, no mass extinction has been recog-nized yet. The extinction event is strongly marked at specific level but shown a complicated situa-tion at generic and family levels. Dramatic changing of the environment, such as the temperature raise due to the greenhouse effect, the marine anoxic habitats caused by a sudden transgression after the regression at the end of Triassic, has been claimed to be the main cause of the extinction. Many hypotheses have been suggested to demonstrate the mechanisms of the environment changing, among which two popular ones are the bolide impact and volcanic eruption. The Triassic-Jurassic (Tr-J) boundary mass extinction event is still poorly understood because no enough data have been obtained from the Tr-J boundary successional sections of both marine and terrestrial sediments, and most of these studies were regionally restricted. The basic aspects of the event and its associated environmental conditions remain poorly characterized and the causal mechanism or mechanisms are equivocal. Some authors even doubt its occurrence. China has many successionally developed terrestrial and marine Tr-J sections. Detailed studies of these sections may be important and significant for well understanding of the event.

关键词： progress, review, end-Triassic, mass extinction, mechanism, Tr-J boundary.

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SHRIMP zircon U-Pb geochronology of early Mesozoic felsic igneous rocks from the southern Lancangjiang and its tectonic implications

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Science China Earth Sciences 2006年第10期49卷 1032-1042页

作者： PENG Touping1,2, WANG Yuejun1, FAN Weiming1, LIU Dunyi3. SHI Yuruo3.& MIAO Laicheng4.1. Key Laboratory of Isotope Geochronology and Geochemistry, Guangzhou institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 51064., China 2. Graduate University of Chinese Academy of Sciences, beijing 10003., China 3. SHRIMP isotope Laboratory, Chinese Academy of Geological Sciences, beijing 10003., China 4. institute of Geology and Geophysics, Chinese Academy of Sciences,{4., China Key Laboratory of Isotope Geochronology and Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China Graduate University of Chinese Academy of Sciences Beijing China SHRIMP isotope Laboratory Chinese Academy of Geological Sciences Beijing China institute of Geology and Geophysics Chinese Academy of Sciences Beijing China

The SHRIMP zircon U-Pb geochronology of three typical samples, including two monzo nitic granites from the Lincang batholith and a rhyolite from the Manghuai Formation are presented in the southern Lancangjiang, western Yunnan Province. The analyses of zircons for the biotite monzonitic granites from the northern (02DX-13.) and southern (20JH-10) Lincang batholith show the single and tight clusters on the concordia, and yield the weighted mean 206Pb/23.U ages of 229.4.± 3.0 Ma and 23..4.± 3.6 Ma, respectively, representing the crystallized ages of these granites. The zircons for the rhyolitic sample (02DX-95) from the Manghuai Formation give a weighted mean 206Pb/23.U age of 23..0 ± 5.0 Ma. These data suggest that the igneous rocks from the Lincang granitic batholith and Manghuai Formation have a similar crystallized age. In combination with other data, it is inferred that both were generated at a narrow age span (~23. Ma) and were originated from the postcollisional tectonic regime. An early Proterozoic 206Pb/23.U apparent age of 1977±4. Ma is additionally obtained from one zircon from the biotite monzonitic granite (southern Lincang batholith), indicative of devel- opment of the early Proterozoic Yangtze basement in the region. These precisely geochronological data provide important constraints on better understanding the Paleozoic tectonic evolution of the Tethys, western Yunnan Province.

关键词： SHRIMP zircon U-Pb dating, Middle Triassic, Lincang granitic batholith, Manghuai Formation rhyolite, southern Lancangjiang.

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The crustal structure under Sanjiang and its dynamic implications:Revealed by seismic reflection/refraction profile between Zhefang and Binchuan,Yunnan

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Science China Earth Sciences 2005年第9期48卷 1329-1336页

作者： ZHANG Zhongjie1, BAI Zhiming1, WANG Chunyong2, TENG Jiwen1, Lü Qingtian3. LI Jiliang1, LIU Yifeng1 & LIU Zhenkuan4.1. institute of Geology and Geophysics, Chinese Academy of Sciences, beijing 100029, China 2. institute of Geophysics, China Seismological Bureau, {3. 100085, China 3. institute of Deposition Resource, Chinese Academy of Geosciences, {3. 10003., China 4. School of Exploration and Information, China University of Geosciences, {3. 100083. China institute of Geology and Geophysics Chinese Academy of Sciences Beijing China institute of Geophysics China Seismological Bureau Beijing China institute of Deposition Resource Chinese Academy of Geosciences Beijing China School of Exploration and Information China University of Geosciences Beijing China

The fault belts in Sanjiang mainly include Jinshajiang-Honghe fault, Lancangjiang fault and Nujiang fault (called Sanjiang faults) in western Yunnan Province, China. By interpreting the wide-angle seismic reflection/refraction profile between Zhefang and Binchuan, which crosses Tengchong and Baoshan blocks in Dianxi (western Yunnan) tectonic zone, we recon- struct the crustal structure with seismic traveltime tomography for crustal P-wave velocity and the seismic scattering image for crustal seismic reflection structure. In this paper, we firstly present the crustal structure images of P-wave velocity and seismic reflection under the wide-angle seismic profile. These results demonstrate that, the crustal velocity structure and seismic reflec- tion structure along the profile can be divided into 3.segments, and there is an obvious difference of crustal structure among the eastern, the western and the middle segment. Generally, crustal P-wave velocities in the Baoshan segment are 0.1―0.2 km/s slower and seismic reflection am- plitudes from Moho discontinuity are stronger than the other 2 segments. In the studied area, crustal thickness is about 4. km, and shows the thickening tendency from west to east along the profile. Additionally, it can be seen that there is one strong-amplitude seismic reflection event as bright points at the depths of 8―10 km, along the segment of 80―115 km of the profile (south- ward of Tengchong); and seismic reflection wave-field from Moho discontinuity varies obviously along the lateral direction. Finally, we make some discussions on the crustal thickening pattern in the Sanjiang fault belt, structural environment of earthquake development and the contact rela- tionship between the Tengchong block, Banshan block and Luxi trough.

关键词： Sanjiang area wide-angle seismic profile crustal structure.

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Patterns of platinum-group elements in mantle peridotite, granulite xenoliths and basalt in Hannuoba

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Chinese Science Bulletin 1999年第18期44卷 1676-1681页

作者： CHU Xuelei, LI Xiaolin, XU Jiuhua and LIU Jianming1. The Research Center of Mineral Resources Exploration , Chinese Academy of Sciences , beijing 100101, China 2. institute of Geology , Chinese Academy of Sciences , beijing 100029, China 3. institute of High Energy Physics , Chinese Academy of Sciences , beijing 100817 , China 4. beijing University of Science and Engineering , beijing 100083. China Corresponding author The Research Center of Mineral Resources Exploration Chinese Academy of Sciences Beijing China institute of Geology Chinese Academy of Sciences Beijing China institute of High Energy Physics Chinese Academy of Sciences Beijing China beijing University of Science and Engineering Beijing China

Neutron activation analysis after preconcentration of nickel sulfide fire assay was used in measurement of Ru, Ph, Pd, Os, Ir, Pt (i.e. PGE elements) and Au concentrations for basalt, mantle and granulite xenoliths in Hannuoba. The chondrite- and primitive mantle-normalized PGE patterns generally exhibit flat (for Iherzolite), negative slope (for harzburgite),

关键词： mantle xenolith granulite xenolith basalt platinum-group element Hannuoba.

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On the periodic solutions of a type of differential-iterative equations

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Chinese Science Bulletin 1998年第3期43卷 204-206页

作者： GE Weigao 1, LIU Zhengrong 2 and YU Yuanhong 3.1. Department of applied Mathematics, beijing institute of Technology, beijing 100081, China 2. Department of Mathematics, Yunnan University, Kunming 650091, China 3. institute of applied Mathematics, C Department of applied Mathematics Beijing Institute of Technology Beijing China Department of Mathematics Yunnan University Kunming China institute of applied Mathematics Chinese Academy of Sciences Beijing China

Sufficient conditions for the existence of periodic solutions to a type of nonautonomous differential_iterative equations are given.

关键词： differential_iterative equation periodic solution fixed point.

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Statistical Characteristics of Metastable Pitting of 3.6 Stainless Steel

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Journal of Materials Science & Technology 2000年第3期16卷 286-290页

作者： Yu ZUO, Haiou DU and Jinping XIONG (Dept. of applied Chemistry, beijing University of Chemical Technology, beijing 100029, China) Dept. of applied Chemistry Beijing University of Chemical Technology Beijing 100029 China

The statistical characteristics of the current fluctuations during metastable pitting of 3.6L stainless steel in NaCI solution were studied using potentiostatic method. The growth rates and peak currents of metastable pits followed log-normal distributions. As potential and chloride concentration increased, both growth rate and peak current of metastable pits increased. The lifetime of metastable pits also followed log-normal distribution, and was almost not affected by potential. Higher growth rates did not definitely result in larger metastable pits. A certain propagation rate range was found beneficial for the micropit to remain growth. At constant potential, the maximum peak currents in different time intervals during a potentiostatic test followed extreme distribution. The statistical characteristics of metastable pitting may be used to predict the tendency of pitting corrosion.

关键词： Statistical Characteristics of Metastable Pitting of 3.6 Stainless Steel

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Fog Detection over China's Adjacent Sea Area by using the MTSAT Geostationary Satellite Data

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Atmospheric and Oceanic Science Letters 2012年第2期5卷 128-133页

作者： LI Jun 1,2,HAN Zhi-Gang 3.CHEN Hong-Bin 1,ZHAO Zeng-Liang 3.and WU Hong-Yi 4.1 Laboratory for Middle Atmosphere and Global Environment Observation (LAGEO),institute of Atmospheric Physics,Chinese Academy of Sciences,beijing {4.,China 2 Graduate University of Chinese Academy of Sciences,beijing 10004.,China 3.beijing institute of applied meteorology,beijing {4.,China 4.beijing Meteorological Bureau,beijing 100089,China Laboratory for Middle Atmosphere and Global Environment Observation (LAGEO) Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Graduate University of Chinese Academy of Sciences Beijing 100049 China beijing institute of applied {3. Beijing 100029 China Laboratory for Middle Atmosphere and Global Environment Observation (LAGEO) Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China beijing Meteorological Bureau Beijing 100089 China

A fog threshold method for the detection of sea fog from Multi-function Transport Satellite (MTSAT1R) infrared (IR) channel data is *** method uses principle component analysis (PCA),texture analysis,and threshold detection to extract sea fog information.A heavy sea fog episode that occurred over China's adjacent sea area during 7 8 April 2008 was detected,indicating that the fog threshold method can effectively detect sea fog areas nearly 24.hours a ***-1R data from March 2006,June 2007,and April 2008 were processed using the fog threshold method,and sea fog coverage information was compared with the meteorological observation report data from *** hit rate,miss rate,and false alarm rate of sea fog detection were 66.1%,27.3.,and 3..9%,*** results show that the fog threshold method can detect the formation,evolution,and dissipation of sea fog events over period of time and that the method has superior temporal and spatial resolution relative to conventional ship *** addition,through MTSAT-1R data processing and a statistical analysis of sea fog coverage information for the period from 2006 to 2009,the monthly mean sea fog day frequency,spatial distribution and seasonal variation characteristics of sea fog over China's adjacent sea area were obtained.

关键词： sea fog MTSAT geostationary satellite spatial distribution seasonal variation

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Using directional data method for analysis on typhoon movement and its probability distribution features

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Acta Oceanologica Sinica 1988年第4期7卷 496-501页

作者： Shi Jiuen, Chen Xiaoming and Xiang Jingtian beijing institute of meteorology, beijing, Chinainstitute of applied Mathematics, Acadcmia Sinica, beijing, China beijing institute of meteorology Beijing China China

In many scientific fields such as meteorology, biology, geography, oceanography and astronomy, the angle value is very important, for example, wind directions, and the directions on which animals and birds migrate. This kind of data is called as directional data. In some problems, it is not expressed as 'angle' value, such as month by month mean temperature, however, it can be changed into a directional data through some transformations. The statistical method of directional data means that the methods of mathematical statistics are used in the treatment of directional data. In this way, data are considered as the points on two-dimensional cycle or higher dimensional sphere. Therefore, this method can also be called statistics on sphere. Because of its own characteristical feature, the statistics of directional data much differ from common statistics. Up to now, research work in this field has just started in China. In this paper, a statistical study on typhoon moving directions after their formation ov

关键词： Using directional data method for analysis on typhoon movement and its probability distribution features data

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A new DNA algorithm to solve graph coloring problem

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Progress in Natural Science:Materials International 2007年第6期17卷 733-738页

作者： Jiang Xingpeng1, Li Yin2, Meng Ya3.and Meng Dazhi2(1. National Laboratory of Pattern Recognition,institute of Automation, Chinese Academy of Sciences, beijing 100080, China 2. College of applied Sciences, beijing University of Technology, beijing 100022, China 3. School of Science, beijing institute of Technology, beijing 100081, China) National Laboratory of Pattern Recognition Institute of Automation Chinese Academy of Sciences Beijing 100080 China National High Magnetic Field Laboratory Florida State University 1800 East Paul Dirac Drive Tallahassee Florida 32306 USA

Using a small quantity of DNA molecules and little experimental time to solve complex problems successfully is a goal of DNA computing. Some NP-hard problems have been solved by DNA computing with lower time complexity than conventional computing. However, this advantage often brings higher space complexity and needs a large number of DNA encoding molecules. One example is graph coloring problem. Current DNA algorithms need exponentially increasing DNA encoding strands with the growing of problem size. Here we propose a new DNA algorithm of graph coloring problem based on the proof of four-color theorem. This algorithm has good properties of needing a relatively small number of operations in polynomial time and needing a small number of DNA encoding molecules (we need only 6R DNA encoding molecules if the number of regions in a graph is R).

关键词： DNA computing NP-hard problem graph coloring problem.

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