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Improvement of the SLP simulation in the coupled AGCM-ocean surface wave model

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chinese Science Bulletin 2005年第20期50卷 2397-2400页

作者： YU Weidong1, 2, 3. LI Zhaoxin4.& YUAN Yeli3.1. Institute of Oceanology, chinese academy of {3., Qingdao 266071, china 2. {4. school of chinese academy of {3., Beijing 10004., china 3. Laboratory of Marine Science and Numerical Modeling, First Institute of Oceanography, State Oceanic Administration, Qingdao 266061, china 4. LMD/CNRS, Univ. Paris 6, Paris, France Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China graduate school of chinese {3. of {4. Beijing 100049 China Laboratory of Marine Science and Numerical Modeling First Institute of Oceanography State Oceanic Administration Qingdao 266061 China LMD/CNRS Univ. Paris 6 Paris France

The coupled atmosphere-ocean general circulation models (CGCM) are nowbecoming the indispensable tools for the climate study. However, most models still suffer fromunrealistic simulations. One problem is the troublesome climate drift. It may come from someunresolved aspects. One possibility is the poor air-sea surface flux description now adopted inCGCM. The commonly used solution for this problem is the so-called flux correction. To deal with it,Hasslemann proposed an alternative solution of prospect. That is to incorporate the ocean surfacewave model into this coupled GCM system so as to establish a coupled atmosphere-wave-ocean *** necessity is clearly seen from the recent field experiment that air-sea momentum flux dependsstrongly on the sea state. So the explicit calculation of the air-sea flux with the aid of the oceansurface wave model is highly desired. Theoretical progress has provided feasibility to such ideaand experiments have been conducted. Recent work also reveals that coupling ocean surface wave modelwith oceanic general circulation model can result in much better reproduction of the upper oceanthermal structure. This further strengthens our belief in the final realization of the coupledatmosphere-wave-ocean modeling system.

关键词：大气海洋循环模式气象学 SLP模拟

Mass Spectrometric Evidence of Heparin Disaccharides for the Catalytic Characterization of A Novel Endolytic Heparinase

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Acta Biochimica et Biophysica Sinica 2004年第12期36卷 840-844页

作者： Yapeng CHAO1,3. Shaoxiang XIONG2, Xiulan CHENG1, and Shijun QIAN1* 1Institute of Microbiology, chinese academy of sciences, Beijing 100080,{3. 2Center of Mass Spectrometry, Institute of Chemistry, chinese academy of sciences, Beijing 100080,{3. 3.8} school of the chinese academy of sciences, Beijing {13.,{3. Institute of Microbiology Chinese Academy of SciencesBeijing 100080 China graduate school of the chinese {3. of {4.Beijing 10003. China Center of Mass Spectrometry Institute of Chemistry Chinese Academy of SciencesBeijing 100080 China

Heparinase from different sources can eliminate heparin or/and heparan sulfate into various low-molecular weight heparins with different characteristics. Porcine intestinal mucosa heparin was de- graded into a series of oligosaccharides by a novel heparinase from the species Sphingobacterium. Disaccha- ride components from the digests were separated and purified by ultrafiltration and HPLC. Five major peaks appeared as three types according to their retention time. The mass spectrometry of peak I mainly gave the non-sulfated disaccharide with the mass of 3.9 Da. Peak II and III were indicated as two major monosulfated disaccharides with molecular mass of 4.7 and 4.9 Da respectively. Moreover, the peak III represented an N- acetyl disaccharide. Both peak IV and V showed the same mass of 4.6 Da, hinting that they were disulfate- substituted disaccharides. No trisulfate-substituted disaccharides were detected in the mixture of the heparin digest though they were abundant in the heparin structure. The results revealed that the heparinase might specifically cut the sites with low sulfated domain in heparin.

关键词： electrospray ionization-mass spectrometry heparin disaccharides heparinase high perfor- mance liquid chromatography Sphingobacterium sp.

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. Institute of Computing Technology, chinese {3. of {4., Beijing 100080, china 3. graduate school of the chinese {3. of {4., Beijing 10003., china school of Information Engineering Zhejiang Forestry College Hangzhou 311300 Zhejiang 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

Mechanism and Defense on Malicious Code

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Wuhan University Journal of Natural sciences 2005年第1期10卷 83-88页

作者： WEN Wei-ping 1,2,3. QING Si-han 1,2,3.1. Institute of Software, the chinese academy of sciences, Beijing 100080,{3. 2.Engineering Research Center for Information Security Technology, the chinese academy of sciences, Beijing 100080,{3. 3.graduate school of the chinese academy of sciences, Beijing 100080,{3. Institute of Software the Chinese Academy of Sciences Beijing 100080 China

With the explosive growth of network applications, the threat of the malicious code against network security becomes increasingly serious. In this paper we explore the mechanism of the malicious code by giving an attack model of the malicious code, and discuss the critical techniques of implementation and prevention against the malicious code. The remaining problems and emerging trends in this area are also addressed in the paper.

关键词： malicious code attacking model mechanism defense system security network security

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, Beijing 100080,{3. 2. {4. school, chinese academy of sciences, Beijing 100060,{3. 3. Tropical Marine Science Institute, National University of Singapore, Singapore 119260 chinese Acad Sci Inst Mech Beijing 100080 Peoples R China chinese Acad Sci Grad Sch Beijing 100060 Peoples R China Natl Univ Singapore Trop Marine Sci Inst 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.

Monitoring of rice crop using ENVISAT ASAR data

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Science china Earth sciences 2006年第7期49卷 755-763页

作者： DONG Yanfang1, 2, SUN Guoqing1,3.& PANG Yong4.1. State Key Laboratory of Remote Sensing Science, Institute of Remote Sensing Applications, chinese academy of {3., Beijing 100101, china 2. {4. University of chinese academy of {3., Beijing 10003., china 3. Department of Geography, University of Maryland, College Park, MD 2074., USA 4. Forest Remote Sensing Lab, Research Institute of Forest Resource and Information Technology, chinese academy of For-estry, Beijing 100091, china 1. State Key Laboratory of Remote Sensing Science Institute of Remote Sensing Applications Chinese Academy of Sciences Beijing 100101 China 2. graduate University of chinese academy of {3. Beijing 100039 China 3. Department of Geography University of Maryland College Park MD 20742 USA 4. Forest Remote Sensing Lab Research Institute of Forest Resource and Information Technology Chinese Academy of Forestry Beijing 100091 China

Because of the cloudy conditions during the rice growth period, rice is one of the agri-cultural crops most suited to monitoring with the SAR instruments. Backscatter response measured by SAR is correlated with rice conditions, including height, density, biomass and structure, which are variable at different growing stages. In this paper, multi-date ENVISAT ASAR Alternating Polarization Mode (APMode) imageries were acquired during the rice crop growing cycle. At the same time, the rice parameters were measured in field. A continuous canopy model was used to compute the back-scattering from rice fields during the growth cycle, and the relationship between rice parameters and radar backscattering coefficients from both ASAR and modeling was analyzed. The effects of polari-zation, incidence angle and polarization on radar backscattering coefficients were analyzed. It was found that simulated radar backscatter has similar trends as ASAR data. This will be meaningful for the further research of rice parameters estimation from ASAR data. Different features show signifi-cantly different signatures in ASAR images and they follow some certain laws, so rice area can be accurately mapped by using multi-temporal SAR images, then rice yield can be estimated.

关键词： rice, ASAR, radar backscattering, model.

Modeling the impact of Australian Plate drift on Southern Hemisphere climate and environment

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chinese Science Bulletin 2005年第14期50卷 1495-1502页

作者： ZHOU Botao1,5, ZHAO Ping2, JIAN Zhimin3.& HE Jinhai4.1. Nansen-Zhu International Research Center, Institute of Atmospheric Physics, chinese academy of {3., Beijing 100029, china 2. Institute of Climate and Environment, chinese academy of Meteoro- logical {3., Beijing 100081, china 3. Laboratory of Marine Geology, Tongji University, Shanghai 200092, china 4. Department of Atmospheric {3., Nanjing Institute of Meteorol- ogy, Nanjing 21004., china 5. graduate school of the chinese academy of {3., Beijing 10003., china Nansen-Zhu International Research Center Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China graduate school of the chinese {3. of {4. Beijing 100039 China Institute of Climate and Environment Chinese Academy of Meteorological Sciences Beijing 100081 China Laboratory of Marine Geology Tongji University Shanghai 200092 China Department of Atmospheric sciences Nanjing Institute of Meteorology Nanjing 210044 China

Using a global atmosphere-ocean coupled model with the present-day and 14.MaB.P. oceanic topogra- phy respectively, two experiments are implemented to inves- tigate the effect of different locations of Australian Plate on the atmospheric circulation in middle-high latitudes of the Southern Hemisphere. The results show that when Austra- lian Plate lay south at 14.MaB.P., both anticyclone circula- tions in the subtropical oceans and cyclone circulation around 60°-70°S are strengthened. Subtropical highs and circumpolar low pressure appear stronger, which results in much stronger Antarctic Oscillation and shorter period of Antarctic Oscillation Index (AOI) at 14.MaB.P. The rainfall and the surface air temperature also change correspondingly. The precipitation decreases around 4.°S and increases around 60°-70°S, and the surface air temperature rises in high latitudes of the South Pacific and descends over the Weddell Sea and its north side. Besides, due to the changes of the temperatures and winds, Antarctic sea ice coverage also changes with its increasing in the Ross Sea and its west re- gions and decreasing in the Weddell Sea.

关键词：半球气候地球环球澳大利亚漂流物海洋地形学

Sequence analysis of mRNA polyadenylation signals of rice genes

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chinese Science Bulletin 2006年第9期51卷 1069-1077页

作者： LU Ying1, 2, GAO Chenxi1,2,3.& HAN Bin1,3.4.. National Center for Gene Research, Shanghai Institutes for Biological sciences, chinese {3. of sciences, Shanghai 20023.,{4. 2. graduate school of the chinese {3. of sciences, Beijing 10003.,{4. 3. Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological sciences, chinese {3. of sciences, Shanghai 20003.,{4. National Center for Gene Research Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai 200233 China graduate school of the chinese {3. of {4. Beijing 100039 China Institute of Plant Physiology and Ecology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai 200032 China

The formation of eukaryotic mRNAs involves the cleavage and polyadenylation of pre- mRNAs. To investigate the sequence requirement of putative polyadenylation signals (PASs), poly(A) sites and downstream elements (DUEs) in 3.-end-pro- cessing in rice, we compared expressed sequences tags (ESTs) with poly(A) extremity to full-length cDNA sequences and constructed a database of 12969 pre- mRNA sequences in ?4.―+4. nt surrounding the poly(A) sites, which were from 9953.genes. The al- ternative poly(A) sites were revealed in approxi- mately 25% of mRNAs. Nearly 80% of pre-mRNAs showed stringent requirement of the YA (CA or UA) at poly (A) sites for polyadenylation. About 7.9% had the AAUAAA signals on ?4.―?1 nt upstream of the poly(A) sites. Over 60% of mRNAs probably used the one- or two-base variants of AAUAAA hexamers as their PASs in 3. fragments. The single-base variants of AAUGAA revealed the high frequency in 11.5% of 3. fragments. The DUEs were detected in 90% of pre- mRNAs, especially more than half of the pre-mRNAs with multi-base variants of AAUAAA had the DUEs surrounding the poly(A) site. The location of DUE is also important for defining the cleavage site. Al- though most of the rice pre-mRNAs did not contain AAUAAA signal, the existence of downstream ele- ments ensured the efficiency of cleavage-polyade-

关键词：多聚腺苷酸序列分析 mRNA 水稻基因工程

Experimental study on phosphorus release from sediments of shallow lake in wave flume

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Science china Earth sciences 2006年第z1期49卷 92-101页

作者： SUN Xiaojing,ZHU Guangwei, LUO Liancong & QIN Boqiang Nanjing Institute of Geography & Limnology, chinese academy of sciences, Nanjing 210008,{3. {4. school of chinese academy of sciences, Beijing 10003.,{3. 1. Nanjing Institute of Geography & Limnology Chinese Academy of Sciences Nanjing 210008 China2. Graduate School of Chinese Academy of Sciences Beijing 100039 China

Influence of wave on sediment resuspension and nutrients release from sediments, collected from Lake Taihu and Lake Chaohu, was studied in flume experiments. Under strong-wave conditions, concentrations of suspended solids (SS), total phosphorus (TP) and dissolved total phosphorus (DTP) in overlying water were increased significantly following the sediments re-suspension. During the experiments on sediments of Lake Taihu and Lake Chaohu, TP concentrations increased 6 times and 3.times, and DTP concentration increased 100% and 70% more than it in presuspension, respectively. Concentration of soluble reactive phosphorus (SRP) of experiment on sediment of Lake Taihu increased 25%. During the massive sediment suspension, the dissolved phosphorus in pore water and much of the phosphorus adsorbed by the sediment particles were released into overlying water. The phenomena in this wave flume experiment are quite similar to the situation observed in situ of Lake Taihu. The critical wave stresses of sediment re-suspension are nearly equal. The change of concentrations of SS, TP, and SRP was the same as that in situ *** study showed that concentrations of TP and SRP in lake water could be increased significantly by wave disturbance. Phosphorus release was significantly enhanced by wave disturbance at the beginning of massive sediment re-suspension, but decreased later.

关键词： shallow lakes, wave disturbance, internal release, phosphorus, wave flume experiment.