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Prediction method for October 2.03 solar storm

Science China(Technological sciences) 2006年第5期49卷 629-640页

作者： XIE Yanqiong1, 2. 3, WEI Fengsi1, FENG Xueshang1 & ZHONG Dingkun1, 2.1. State Key Laboratory of Space Weather, Center for Space Science and Applied Research, chinese academy of {2., Beijing 100080, China 2. graduate school, chinese academy of {2., Beijing 100039, China 3. Institute of Meteorology, PLA University of Science and Technology, Nanjing 2.1101, China State Key Laboratory of Space Weather Center for Space Science Applied Research Chinese Academy of Sciences Beijing 100080 China graduate school Chinese Academy of Sciences Beijing 100039 China Institute of Meteorology PLA University of Science Technology Nanjing 211101 China

Aiming at two intense shock events on October 2. and 2., 2.03, this paper presents a two-step method, which combines synoptic analysis of space weather ——“observing” and quantitative prediction ——“palpating”, and then uses it to test predictions. In the first step of “observing”, on the basis of observations of the solar source surface magnetic field, interplanetary scintillation (IPS) and ACE spacecraft, we find that the propagation of the shocks is asymmetric relative to the normal direction of their solar sources, and the Earth is located near the direction of the fastest speed and the greatest energy of the shocks. As the two fast ejection shock events, the fast explosion of coronal mass of the extremely high temperature, the strong magnetic field, and the high speed background solar wind are also helpful to their rapid propagation. In the second step of “palpating”, we adopt a new membership function of the fast shock events for the ISF method. The predicted results show that for the onset time of the geomagnetic disturbance, the relative errors between the observational and the predicted results are 1.8% and 6.7%; and for the magnetic disturbance magnitude, the relative errors are 4.1% and 3.1%, re- spectively. Furthermore, the comparison among the predicted results of our two-step method with those of five other prevailing methods shows that the two-step method is advantageous. The results tell us that understanding the physical features of shock propagation thoroughly is of great importance in improving the prediction precision.

关键词： solar storm, interplanetary shock, interplanetary scintillation, two-step method, ISF method.

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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 {2., Beijing 100080, China 2.enter of Mass Spectrometry, Institute of Chemistry, chinese academy of {2., Beijing 100080, China 3graduate school of the chinese academy of {2., Beijing 100039, China Institute of Microbiology Chinese Academy of SciencesBeijing 100080 China graduate school of the {2. academy of sciencesBeijing {5. 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 379 Da. Peak II and III were indicated as two major monosulfated disaccharides with molecular mass of 417 and 45. Da respectively. Moreover, the peak III represented an N- acetyl disaccharide. Both peak IV and V showed the same mass of 496 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.

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Study on growth and properties of novel γ-LiAlO_2.substrate

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Science China(Technological sciences) 2006年第2期49卷 188-193页

作者： ZOU Jun1,2. ZHOU Shengming1, XU Jun1 & ZHANG Rong3 1. Shanghai Institute of Optics and Fine Mechanics, chinese academy of {2., Shanghai 2.1800, China 2. graduate school of chinese academy of {2., Beijing 100039, China 3. Laboratory of Solid State Microstructures and Department of Physics, Nanjing University, Nanjing 2.0093, China 1. Shanghai Institute of Optics and Fine Mechanics Chinese Academy of Sciences Shanghai 201800 China 2. graduate school of {2. academy of {5. Beijing 100039 China 3. Laboratory of Solid State Microstructures and Department of Physics Nanjing University Nanjing 210093 China

Transparent γ-LiAlO2.single crystal has been grown by Temperature Gradient technique. The surface of the wafer annealed in O2.atmosphere at 1100°C for 70 h became opaque and Li-poor phase (LiAl5.8); while, that annealed in Li-rich atmosphere kept transparent and smooth. The full-width at half maximum value dropped to 30 arcsecs when the wafer was annealed in Li-rich atmosphere. That annealed in O2.atmosphere increased to 78 arcsec. Compared with absorption spectra, we can conclude that the 196 nm absorption peak was caused by Li vacancies and the 736 nm peak was caused by O vacancies.

关键词： γ-LiAlO2 crystal, scanning electron micrograph (SEM), absorption spectra.

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Research on Jiuquan-Jiayuguan-Yumen Region's Dynamic Changing of Urbanization Based on Self-Organizing Model

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chinese Journal of Population,Resources and Environment 2005年第3期3卷 22-28页

作者： Li Ming 1,2.& Fang Chuanglin 2.1 graduate school of the {2. {5. of sciences, Beijing {5.,China 2.Institute of Geographical sciences and Natural Resources Research, CAS, Beijing 100101, China graduate school of the {2. academy of sciences Beijing 100039 China Institute of Geographical sciences and Natural Resources Research CAS Beijing 100101 China

Based on the self-organizing modeling principle in the dissipative structure theory, the paper regards the migration coupling between the regions as the influence factor to create the model of regional urbanization simulation and prediction, which is more practical to simulate the space-time and dynamic evolvement characteristics of regional urbanization level. According to the historical data about the population and urbanization of Jiuquan, Jiayuguan andYumen cities, the past 5. years' dynamic evolvement trend is simulated and the following 5. years' dynamic evolvement trend is predicted with the urbanization dynamic evolvement model based on the self-organizing model. The analysis of effective factors such as economic increase, resources exploitation, ecosystem construction, traffic location, national policies, population migration are given, then the reasons of the dynamic evolvement differences of the three cities' urbanization are drawn. The study suggests that the self-organizing model is fit for the simulation of Jiuquan-Jiayuguan-Yumen regional urbanization level in the past 5. years, and the departure between the stimulant and the actual data is under 5., so it can be used to predict the urbanization future of the three cities. The predicted results show that the regional population will reach 1.074 million and the regional urbanization level will be 72.5.%.

关键词： self-organizing urbanization dynamic evolvement Jiuquan-Jiayuguan-Yumen region

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Spatial heterogeneity of the driving forces of cropland change in China

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Science China Earth sciences 2005年第12期48卷 2231-2240页

作者： LIU Xuhua1,2. WANG Jinfeng1, LIU Mingliang4,1 & MENG Bin1,2.3 1. Institute of Geographic sciences and Natural Resources Research, chinese {2. of sciences, Beijing 100101, China 2. graduate school of the chinese academy of sciences, Beijing {5., China 3. College of Arts and sciences of Beijing Union University, Beijing 100083, China 4. school of Forestry and Wildlife sciences, Auburn University, Auburn, Alabama, AL36849, USA 1. Institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences 100101 Beijing China 2. graduate school of the chinese academy of sciences 100039 Beijing China 3. school of Forestry and Wildlife sciences Auburn University Auburn AL36849 Alabama USA 4. College of Arts and sciences of Beijing Union University 100083 Beijing China

By using digital satellite remote sensing data acquired in 1987―1989 and 1999―2.00 and GIS combined with the natural and socio-economic data, this paper drew an integrated zonation of the cropland change and its driving forces in China. The results indicated that the cropland change in the study period was constrained by geographical factors and driven by cli-mate change as well as socio-economic system. Moreover, the regional differences of the drivers for cropland change were significant. In the midwest of China, natural condition changes and geographical background were the main constraints and drivers, while in Eastern China, social and economic changes and economic policies were the main driving forces. The cropland loss was nationwide. The dominant factors to cause this decrease included buildup of developing area to attract foreign capital and technologies, changes of industry structure due to urban in-fluence, the change of employment notions thanks to living standard improvement, rapid ur-banization due to the expansion of cities and towns, the diminished farming net income partly because of the global warming effects, and the rapid economic growth stimulated by the con-venient transportation system. These factors interact and interdepend with each other to cause the cropland loss in China recently. The reasons for the increase of cropland were primarily the cultivation and deforestation by the farmers who want to increase income. This study on the mechnism of LUCC relied on the cropland change integrated classification considering the natural or human factors both inside and outside the region, which provides a new approach to study the integrated regionalization and LUCC mechanism.

关键词： land use change, driving force, integrated classification, spatial statistics, cropland, China.

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Identification of novel SINEs from Cyprinidae and their evolutionary significance

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Progress in Natural Science:Materials International 2007年第3期17卷 270-279页

作者： HAN Yawei, HE Slumping and CHEN Yiyu ( Institute of Hydrobiology, chinese academy of {2., Wuhan 430072. China. graduate {5., chinese academy of {2., Beijing 100039, China) [a]Institute of Hydrobiology Chinese Academy of Sciences Wuhan China [b]graduate school Chinese Academy of Sciences Beijing China

Short interspersed nuclear elements (SINEs) are widespread among eukaryotic genomes. They are repetitive DNA sequences that have been amplified by retrotransposition. In this study, a class of SINEs were isolated from the Opsariichthys bidens genome, and named Opsar. Sequence analysis confirmed that Opsar is a new class of typical SINEs derived from tRNA molecules. With the tRNA-derived region of Opsar and through BLASTN search, we further identified Zb-SINEs from the zebrafish genome, which includes two groups: Zb-SINE-A and Zb-SINE-B. The Zb-SINE-A. group comprises subfamilies of -Al--A5. and the Zb-SINE-B group is a dimer of the tRNA -derived region and shares a similar dimeric composition to Alu. Zb-SINEs are composed of three distinct regions: a 5. end tRNA-derived region, a tRNA-unrelated region and a 3’ end AT-rich region. The flanking regions are AT rich. The average length of Zb-SINEs elements is about 340 bp. Zb-SINEs account for as much as 0.1 % of the whole zebrafish genome. About 70% of the Zb-SINEs are on chromosomes 11, 18, and 19. These Zb-SINEs were characterized by PCR and dot hybridization. The distribution pattern of Zb-SINEs in genome strongly supports the master genes model. The tRNA-derived regions of Opsar and Zb-SINEs were compared with the tRNAAla gene, and they showed 76% similarity, indicating that Opsar and Zb-SINEs originated from an inactive tRNA sequence or a tRNA -like sequence. In view of the evolutionary status of zebrafish in the Cyprinidae, we deduced that Zb-SINEs were a very old class of interspersed sequences.

关键词： short interspersed nuclear elements (SINEs) master gene model Opsar Zb-SINEs and Cyprinidae.

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A formal model of fair exchange protocols

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Science in China(Series F) 2005年第4期48卷 499-512页

作者： QING Sihan1,2.3 & LI Gaicheng1,2.3 1. Engineering Research Center for Information Security Technology, Institute of Software, chinese Aca- demy of sciences, Beijing 100080, China 2. Beijing Zhongke Ansheng Corporation of Information Technology, Beijing 100080, China 3. {2. school of the chinese {5. of sciences, Beijing 100039, China 1. Engineering Research Center for Information Security Technology Institute of Software Chinese Academy of Sciences 100080 Beijing China 2. Beijing Zhongke Ansheng Corporation of Information Technology 100080 Beijing China 3. graduate school of the {2. academy of sciences 100039 Beijing China

Based on the study of existing fair exchange protocols, this paper sets up an accurate formal model by stepwise refinement. In the process of refinement an unreliable channel is employed to simulate an attack behavior. The model provides a novel formal definition of exchanged items, and presents the formal goals for fairness, accountability, etc., reflecting the inherent requirements for fair exchange protocols across-the-board. In order to check, prove, and design fair exchange protocols effectively and efficiently, the model puts forward a novel property of abuse-freeness which applies to all fair exchange protocols, gives a formal definition for trust strand of the third party, and presents general criteria of designing a secure and effective fair exchange protocol. Taking a typical fair exchange protocol as an example, this paper presents the analysis steps of fair exchange protocols appealing to our model. An unknown attack is uncovered. The analysis reveals the process of a complete attack, discovering deeper reasons for causing an attack. Finally, we modify the flawed protocol and the revised protocol ensures the desirable properties.

关键词： events local causal relation local temporal relation global relation exchanged item security goals.

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Origin of the Red Earth sequence on the northeastern Tibetan Plateau and its implications for regional aridity since the middle Miocene

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Science China Earth sciences 2006年第5期49卷 505-517页

作者： WANG Xianyan1,7, LU Huayu1,2. JI Junfeg3, WANG Xiaoyong1,7, ZHAO Jingbo4, HUANG Baochun5.& LI Zhen6 1. SKLLQG, Institute of Earth Environment, chinese academy of {2., Xi’an 710075. China 2. Department of Urban and Resources {2., Nanjing University, Nanjing 2.0093, China 3. Department of Earth {2., Nanjing University, Nanjing 2.0093, China 4. Department of Geography, Shaanxi Normal University, Xi’an 710062. China 5. Institute of Geology and Geophysics, chinese academy of {2., Beijing 10002., China 6 Department of Geography, Qinghai Normal University, Xining 810008, China 7. graduate {15. of the chinese academy of {2., Beijing 100039, China 1. SKLLQG Institute of Earth Environment Chinese Academy of Sciences Xi’an 710075 China 7. graduate school of the {2. academy of sciences Beijing 100039 China 2. Department of Urban and Resources sciences Nanjing University Nanjing 210093 China 3. Department of Earth sciences Nanjing University Nanjing 210093 China 4. Department of Geography Shaanxi Normal University Xi’an 710062 China 5. Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China 6. Department of Geography Qinghai Normal University Xining 810008 China

The Red Earth deposit around Xining, northeastern Tibetan Plateau, has beenstudied in terms of soil micro-structure, grain-size distribution, major- and trace-elementchemistry and magne-tostratigraphy. Field investigations indicate that the Red Earth sequenceconsists of 2. visually definable yellow-brown and weakly-developed soils interbedded with reddishstrongly-developed soils, and has a similar structure to the aeolian Red Clay deposit on the chineseLoess Plateau. Grain-size analysis shows that the Red Earth deposit is very fine-grained with anegligible sand fraction ( > 63 μm). Thin-section observations under light microscopy show that thedeposit has a clayey texture and the coarse fraction ( > 10 μm) mainly consists of quartz,feldspar and micas. Pyroxene and hornblende were also observed. This mineralogical composition ofthe coarse fraction is similar to that of the Quaternary loess. In addition, all of the mineralgrains are semi angular semi-angular and are generally finer than 63 μm. There is a good agreementbetween the major and minor trace element chemistry of loess-soil units and the Red Earth *** REE distributions of the loess-soil and the Red Earth deposit are similar in shape, withenriched LREE and fairly flat HREE profiles and a clear negative Eu anomaly. The geochemicalcharacteristics of the Red Earth deposit are also identical to those of upper continental crust,thus indicating a wind-blown origin. Magnetostratigraphic investigation shows that onset of the RedEarth deposition predates 11.4 Ma BP (13.6 Ma at a nearby site). The distribution of the reportedMiocene aeolian loess at Qin''an of the Loess Plateau is still unknown. Our results indicate thatthis aeolian deposit had extended to the northeastern Tibetan Plateau by at least the middleMiocene. The similarity of the element geochemistry between the Red Earth deposit and the overlyingloess shows that they may have similar sources and dynamic transport system, and may indicate thatthe

关键词： Red Earth deposit, Northeastern Tibetan Plateau, aeolian deposit, aridity of Asia, the middle Miocene.

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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 {2., Beijing 10002., China 2. Institute of Climate and Environment, chinese academy of Meteoro- logical {2., Beijing 100081, China 3. Laboratory of Marine Geology, Tongji University, Shanghai 2.0092. China 4. Department of Atmospheric {2., Nanjing Institute of Meteorol- ogy, Nanjing 2.0044, China 5. graduate school of the chinese academy of {2., Beijing {12., China Nansen-Zhu International Research Center Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China graduate school of the {2. academy of sciences 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 40°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

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De-interlacing technique based on total variation with spatial-temporal smoothness constraint

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Science in China(Series F) 2007年第4期50卷 561-575页

作者： YIN XueMin1,2.3, YUAN JianHua1,2. LU XiaoPeng1,2.& ZOU MouYan1,2.1 Institute of Electronics, chinese {5. of {2., Beijing 100080, China 2.graduate school, chinese {5. of {2., Beijing 100039, China 3 Jiuquan Satellite Launch Center, Lanzhou 732.5., China 1. Institute of Electronics Chinese Academy of Sciences Beijing 100080 China 2. graduate school Chinese Academy of Sciences Beijing 100039 China 3. Jiuquan Satellite Launch Center Lanzhou 732750 China

This paper introduces a new method of converting interlaced video to a progressively scanned video and image, The new method is derived from Bayesian framework with the spatial-temporal smoothness constraint and the MAP is done by minimizing the energy functional, The half-quadratic regularization method is used to solve the corresponding partial differential equations （PDEs）, This approach gives the improved results over the conventional de-interlacing methods, Two criteria are proposed in the paper, and they can be used to evaluate the performance of the de-interlacing algorithms,

关键词： video processing de-interlacing total variation spatio-temporai smoothness constraint PDEs half-quadratic regularization

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