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Digital image analysis of palaeoenvironmental records and applications

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chinese Science Bulletin 2002年第23期47卷 1957-1963,2025-2026页

作者： SUN Donghuai1,2. LIU Yu2.& TAN Ming31. South china Sea institute of Oceanology,{2.. Guangzhou 510301, china 2. State Key laboratory of Loess and Quaternary Geology, Earth Environmental institute,{2., Xi’an 710075, china 3. institute of Geology and Geophysics,{2., beijing 10002., china South china Sea institute of Oceanology Chinese Academy of Sciences Guangzhou China State Key laboratory of Loess and Quaternary Geology Earth Environmental Institute Chinese Academy of Sciences Xi’an China institute of Geology and Geophysics Chinese Academy of Sciences Beijing China

Environmental change signals in geological or biological records are commonly reflected on their reflecting or transmitting images. These environmental signals can be extracted through digital image analysis. The analysis principle involves section line selection, color value reading and calculating environmental proxy index along the section lines, layer identification, auto-chronology and investigation of structure evolution of growth bands. On detailed illustrations of the image technique, this note provides image analyzing procedures of coral, tree-ring and stalagmite records. The environmental implications of the proxy index from image analysis are accordingly given through application demonstration of the image technique.

关键词： digital image environmental records.

Forcing mechanism of the Pleistocene east Asian monsoon variations in a phase perspective

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Science china Earth sciences 2005年第10期48卷 1708-1717页

作者： TIAN Jun1,2. WANG Pinxian1, CHENG Xinrong1, WANG Rujian1 & SUN Xiangjun1,3 1. State Key laboratory of Marine Geology, Tongji University, Shanghai 2.0092. china 2. {2. of Geology and Geophysics, chinese academy of sciences, beijing 10002., china 3. {2. of Botany, chinese academy of sciences, beijing 100093, china Tongji University chinese academy of {2.

The deep sea records from the ODP Sites 1143 and 1144 in the northern and southern South china Sea (SCS), including foraminiferal δ 18O and δ 13C, Opal% and pollen percentage, reveal that the variations of the east Asian monsoon have been closely correlated with the variations of the Earth’s orbital parameters (eccentricity, obliquity and precession) and the global ice volume on orbital scale. All the monsoonal proxies show strong 100 ka, 41 ka and 2. ka cycles. Although G. ruber δ 13C of Site 1143 is coherent with the ETP (ETP= normalized (eccentricity + obliquity-precession) at eccentricity, obliquity and precession bands, most of the coherent relationship focuses on the precession band, and the other monsoonal proxies are coherent with the ETP only at the precession band, which indicate that precession dominates the Pleistocene tropical climate changes. The phase relationship of the monsoonal proxies with the foraminiferal δ 18O implies that the global ice volume changes have played a significant role in modulating the east Asian monsoon climate, at least dominating the winter monsoon. This forcing mechanism of the east Asian monsoon is apparently different from that of the Indian ocean mon-soon. The variations of the east Asian monsoon at the precession band, at least that of the winter monsoon, have been controlled not only by the sensible heating but also by the latent heating of the surface water in the South china Sea.

关键词： South china Sea, ODP, east Asian monsoon, orbital forcing, global ice volume.

ON DISCRETE PROJECTION AND NUMERICAL BOUNDARY CONDITIONS FOR THE NUMERICAL SOLUTION OF THE UNSTEADY INCOMPRESSIBLE NAVIER-STOKESEQUATIONS

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Journal of Computational Mathematics 2002年第1期20卷 35-56页

作者： Lan Chieh Huang (ICMSEC, academy of Mathematics and System sciences,{2., beijing 100080, china) ICMSEC Academy of Mathematics and System Sciences Chinese Academy of Sciences 北京 100080

Focuses on a study on the fully implicit Crank Nicholson (CN) schemes and three projection methods for approximate preservation of component-consistency under projection. Transformation from incompressible Navier-Stokes equations to differential algebraic equations CN schemes; Local errors of CN projection methods; Numerical boundary conditions.

关键词： differential algebraic equations discrete projection numerical boundary conditions

The mechanism of the effects of the upwelling mean on the ENSO event mature phase locking

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Science china Earth sciences 2007年第8期50卷 1266-1272页

作者： YAN BangLiang CMSR, institute of Atmospheric Physics, chinese academy of sciences, {2. 10002., china CMSR Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China

The mechanism of the effects of the upwelling mean on the ENSO event mature phase locking is ex-amined by using a mixed-mode model. The results show that the positive feedback process of the ef-fects of the seasonal variation of the upwelling mean on the Kelvin wave is the mechanism of the locking of the event mature phase to the end of the calendar year. The memory of the Rossby waves for the sign-shifting of the sea surface temperature anomaly from positive to negative 6 months before the cold peak time is the other mechanism of the locking of the La Nia event mature phase to the end of the calendar year. The results here are different from previous ones which suggest that the balance between cold and warm trends of sea surface temperature anomaly is the mechanism involved. The cold trend is caused by the upwelling Kelvin wave from upwelling Rossby wave reflected at the western boundary, excited by the westerly anomaly stress over the central Pacific and amplified by the seasonal variation of the coupled strength in its way propagating westward. The warm trend is caused by the Kelvin wave forced by the western wind stress over the middle and eastern equatorial Pacific. The cause of the differences is due to the opposite phase of the seasonal variation of the upwelling mean to that in the observation and an improper parameterization scheme for the effects of the seasonal varia-tion of the upwelling mean on the ENSO cycle in previous studies.

关键词： Kelvin wave Rossby wave interaction between atmosphere and sea positive feedback

CBCR:CBC MAC with rotating transformations

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Science china(Information sciences) 2011年第11期54卷 2247-2255页

作者： ZHANG LiTing 1,2.WU WenLing 1,ZHANG Lei 1 & WANG Peng 2. State Key laboratory of Information Security,institute of Software,{2. academy of sciences,beijing 100190,china 2.Graduate University of chinese academy of sciences,beijing 100049,china State Key laboratory of Information Security Institute of Software Chinese Academy of Sciences Beijing China Graduate University of chinese academy of sciences Beijing China

Message authentication codes (MACs) are widely used to protect data integrity and data origin authentication in *** this paper,we propose a new block-cipher-based MAC algorithm,CBCR,with provable security for arbitrary-length *** adopts rotating operations in the end of cipherblock-chaining structure,and it appends fixed-length prefixes to all messages,which implies flexible usages in *** example,these fixed-length prefixes can be filled with some security parameters,message redundancies,*** also propose CBCR0,a special case of CBCR that sets its prefix to be an all-zero *** with CMAC,a recommended standard by the US National institute of Standards and Technology (NIST),CBCR0 enjoys all the advantages that CMAC has,but requires less memory;so,in practical applications,CBCR0 behaves as well as CMAC does,and it is even more suitable for environments with limited memory resources,*** cards.

关键词： message authentication code cipher block chaining block cipher provable security

Topography and functional information of plasma membrane

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Science china(Life sciences) 2008年第2期51卷 95-103页

作者： SUN DeLan1, CHEN JianMin1, SONG YanMei1, ZHU ChuanFeng2. PAN GeBo2.& WAN LiJun2.1 Key laboratory of Photosynthesis and Environmental Molecular Physiology, institute of Botany,{2., beijing 100093, china 2.institute of Chemistry,{2., beijing 100080, china Key laboratory of Photosynthesis and Environmental Molecular Physiology Institute of Botany Chinese Academy of Sciences Beijing China institute of Chemistry Chinese Academy of Sciences Beijing China

By using atomic force microscope (AFM), the topography and function of the plasmalemma surface of the isolated protoplasts from winter wheat mesophyll cells were observed, and compared with dead protoplasts induced by dehydrating stress. The observational results revealed that the plasma membrane of living protoplasts was in a state of polarization. Lipid layers of different cells and membrane areas exhibited distinct active states. The surfaces of plasma membranes were unequal, and were characterized of regionalisation. In addition, lattice structures were visualized in some regions of the membrane surface. These typical structures were assumed to be lipid molecular complexes, which were measured to be 15.8±0.09 nm in diameter and 1.9±0.3 nm in height. Both two-dimensional and three-dimensional imaging showed that the plasmalemma surfaces of winter wheat protoplasts were covered with numerous protruding particles. In order to determine the chemical nature of the protruding particles, living protoplasts were treated by proteolytic enzyme. Under the effect of enzyme, large particles became relatively looser, resulting that their width was increased and their height decreased. The results demonstrated that these particles were likely to be of protein nature. These protein particles at plasmalemma surface were different in size and unequal in distribution. The diameter of large protein particles ranged from 2.0 to 440 nm, with a central micropore, and the apparent height of them was found to vary from 12.to 40 nm. The diameter of mid-sized protein particles was between 40―60 nm, and a range of 1.8―5 nm was given for the apparent height of them. As for small protein particles, obtained values were 12.40 nm for their diameter and 0.7―2.2.nm for height. Some invaginated pits were also observed at the plasma membrane. They were formed by the endocytosis of protoplast. Distribution density of them at plasmalemma was about 16 pits per 15 μm2. According to their size, we clas

关键词： atomic force microscope winter wheat protoplast plasma membrane surface membrane protein invaginated pits

Effect of rock mass structure and block size on the slope stability——Physical modeling and discrete element simulation

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Science china(Technological sciences) 2005年第Z1期48卷 1-17页

作者： LI Shihai1, LIAN Zhenzhong1,2.& J. G. Wang3 1. institute of Mechanics, chinese academy of sciences, {2. 100080, china 2. Graduate School, chinese academy of sciences, {2. 100060, china 3. Tropical Marine Science institute, National University of Singapore, Singapore 1192.0 institute of Mechanics Chinese Academy of Sciences Beijing 100080 China Graduate School Chinese Academy of Sciences Beijing 100060 China Tropical Marine Science institute National University of Singapore Singapore 119260 Singapore

This paper studies the stability of jointed rock slopes by using our improved three-dimensional discrete element methods (DEM) and physical modeling. Results show that the DEM can simulate all failure modes of rock slopes with different joint configurations. The stress in each rock block is not homogeneous and blocks rotate in failure development. Failure modes depend on the configuration of joints. Toppling failure is observed for the slope with straight joints and sliding failure is observed for the slope with staged joints. The DEM results are also compared with those of limit equilibrium method (LEM). Without considering the joints in rock masses, the LEM predicts much higher factor of safety than physical modeling and DEM. The failure mode and factor of safety predicted by the DEM are in good agreement with laboratory tests for any jointed rock slope.

关键词： rock masses, slope stability, DEM simulation, block size effect, joints configuration effect, limit equilibrium method.

Preparation of I_2.Clusters and Their Absorption Spectra

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Journal of Materials Science & Technology 1997年第6期13卷 518-520页

作者： Zhaojun LIN Zhanguo WANG Wei CHEN and Lanying LIN(Lab. of Sendconductor Materials Science, institute of semiconductors, chinese academy of sciences,{2. 1.0083. china) Lab. of Semiconductor Materials Science Institute of Semiconductors Chinese Academy of Sciences Beijing 100083 China

Samples have been prepared at different temperatures by loading I2.molecules into the cages of zeolite 5A, and the measurements of the absorption spectra have been carried out for the prepared samples. It is shown that I2.molecular clusters are formed in the cages of zeolite 5A,and it is also found that moIecuIar clusters which are bonded with intermoIecuIar forces have an important feature, namely, the intermolecular distance in molecular clusters can be changed on different preparing conditions and the blue shift of absorption edges can not be as the criterion of forming molecular clusters.

关键词： OO Preparation of I2.Clusters and Their Absorption Spectra nm

Modern microbialites and their environmental signifi-cance,Meiji reef atoll,Nansha (Spratly) Islands,South china Sea

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Science china Earth sciences 2008年第4期51卷 608-617页

作者： SHEN JianWei1 & WANG Yue1,2.1 Department of Marine Geology, South china Sea institute of Oceanology Key {2. of Marginal Sea Geology, South china Sea institute of Oceanology and Guangzhou institute of Geochemistry, chinese academy of sciences, Guangzhou 510301, china 2.Graduate University of the chinese academy of sciences, beijing 100049, china Department of Marine Geology South China Sea Institute of Oceanology Guangzhou China Key laboratory of Marginal Sea Geology South China Sea Institute of Oceanology and Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China Graduate University of the chinese academy of sciences Beijing China

Meiji (Mischief) coral atoll, in Nansha (Spratly) Islands, South china Sea, consists of an annular reef rim surrounding a central lagoon. On the atoll rim there are either protuberant 'motu' (small coral patch reefs on the rim of atoll) islets or lower sandy cays that contain modern microbialite deposits on the corals in pinnacles and surrounding bottoms of the atoll. Microbialites, including villiform, hairy, and thin spine growth forms, as well as gelatinous masses, mats and encrustation, developed on coral colonies and atoll rim sediments between 0 and 15 m deep-water settings. The microbialites were produced by natural populations of filamentous cyanobacteria and grew on (1) bulbous corals together with Acropora sp., (2. on massive colonies of Galaxea fascicularis, (3) on dead Montipora digitata, and (4) on dead Acropora teres, some hairy microbialite growing around broken coral branches. This study demonstrates that microbial carbonates are developed in coral reefs of South china Sea and indicates that microbial processes may be important in the construction of modern reef systems. The results have significance in the determination of nature and composition in microorganisms implied in the formation ancient microbialites, and permit evaluation of the importance of microbial deposits in mo-dern coral reefs and of 'microbialites' in biogeochemical cycles of modern coral reef systems. The re-sults also provide evidence of modern analogues for ancient microbialites in shallow-water settings, and combine with sedimentological studies of ancient microbialites to understand their controls.

关键词： Microbialite Meiji reef Nansha Island South china Sea