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Petrogenesis and dating of the Kangding complex,Sichuan Province

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Science china Earth Sciences 2005年第5期48卷 622-634页

作者： CHEN Yuelong 1 , LUO Zhaohua 1 , ZHAO Junxiang, LI Zhihong, ZHANG Hongfei & SONG Biao 3.1. Faculty of Earth Sciences and Natural Resources, china University of Geosciences, beijing 100083. china 2. Faculty of Earth Sciences, china University of Geosciences, Wuhan 43.074, china 3. beijing shrimp center, Institute of Geology, Chinese Academy of Geological Sciences, beijing 10003., china Faculty of Earth Sciences and Natural Resources China University of Geosciences Beijing China Faculty of Earth Sciences China University of Geosciences Wuhan China beijing shrimp center Institute of Geology Chinese Academy of Geological Sciences Beijing China

An analysis of major and trace element geochemistry and shrimp U-Pb zircon dating of mafic, intermediate, and felsic rocks from the Mianning metamorphic complex of Si- chuan Province was conducted. One of our conclusions is that a majority of the zircons crystal- lized between 721 and 773.Ma in a magmatic regime. The complexes contain early to late Pa- leo-proterozoic relict zircons from ancient continental crust. The oldest age, 2468 Ma, may rep- resent the basement of the Yangtze block. Overgrowth zircon rims and palingenetic zircons have been observed and dated, and are believed to have formed after crystallization, during Paleozoic and Mesozoic metamorphic-anatexis. We also conclude that depletion of Nb, Ta, HREE, in a spider-diagram normalized to primitive mantle and calc-alkaline association, implies that they formed in island-arc or under-plating settings.

关键词： Kangding complex, zircons, shrimp, tectonic setting.

A preliminary study on seismic design criteria of offshore platforms in Bohai Sea of china

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Earthquake Engineering and Engineering Vibration 2010年第2期9卷 223-231页

作者： Peng Yanju1,Lu Yuejun1,Yan Jiaquan2,Tang Rongyu1,Wang Junqin3.and Li Jiagang3.1. Institute of Crustal Dynamics,china Earthquake Administration,beijing 100085,china 2. Institute of Geophysics,china Earthquake Administration,beijing 100081,china 3. beijing Research center of china National Offshore Oil Corp.,beijing 100027,china Institute of Crustal Dynamics China Earthquake Administration Beijing 100085 China

This paper analyzes the seismicity in Bohai Sea,introducing a shape factor K to characterize the seismic risk distribution in sub-regions of the sea. Based on the seismic design ground motions for 46 platforms located in the Bohai Sea,a statistical analysis was performed for different peak ground acceleration (PGA) ratios at two different probability levels. In accordance with the two-stage design method,a scheme of two seismic design levels is proposed,and two seismic design objectives are established respectively for the strength level earthquake and the ductility level earthquake. By analogy with and comparison to the Chinese seismic design code for buildings,it is proposed that the probability level for the strength level earthquake and ductility level earthquake have a return period of 200 and 1000 - 2500 years,respectively. The validity of these proposed values is discussed. Finally,the PGAs corresponding to these two probability levels are calculated for different sub-regions of the Bohai Sea.

关键词： fixed offshore platform seismic design level seismic design objective return period Bohai Sea

Petrogenesis of Songshugou dunite body in the Qinling orogenic belt, Central china: Constraints from geochemistry and melt inclusions

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Science china Earth Sciences 2005年第8期48卷 1146-1157页

作者： SU Li1,2, SONG Shuguang3.& ZHOU Dingwu1 1. Key Laboratory of Continental Dynamics of the Ministry of Education, Department of Geology, Northwestern University, Xi’an 710069, china 2. The Geological Lab center, china University of Geosciences ({3.), {3. 100083. china 3. Key Laboratory of Orogenic Belts of the Ministry of Education, Department of Geology, Peking University, {3. 100871, china Key Laboratory of Continental Dynamics of the Ministry of Education Department of Geology Northwestern University Xi’an China The Geological Lab center China University of Geosciences (Beijing)Beijing China Key Laboratory of Orogenic Belts of the Ministry of Education Department of Geology Peking University Beijing China

The Songshugou dunite body, which occupies an area of about 20 km2, is the largest ultramafic massif in the eastern Qinling orogenic belt, Central china. The major compo-nent of this body is dunitic rocks including mylonitic dunite and coarse-grained dunite; they oc-cupy about 95 vol% of the total body. Petrography, mineral composition, major and trace ele-ments and primitive melt inclusions have been investigated in this paper; all revealed that this dunite body is the product of melt-rock interaction by porous percolation flow. In comparison with dunite sills or veins in harzburgite from the basal part of Oman ophiolite, this dunite body is characterized by lower contents of Al2O3. CaO and HREE but higher content of highly incom-patible elements and Zr and Hf. The LREE enriched patterns and primitive mantle normalized spidergrams of trace elements are also different from the Oman dunite. Combining with melt in-clusions observed in olivines, we conclude that this dunite body is the product of large- scale porous percolation flow of high-MgO melts within depleted mantle peridotites. The high-MgO magma, in essence, was most probably produced at the hot head of an upwelling mantle plume. The occurrence of the Songshugou dunite body is closely associated with the activity of mantle super-plume in Neo-Proterozoic era in the Yangtze Craton.

关键词： Songshugou dunite body, geochemistry, melt inclusion, mantle plume, Qinling orogenic belt.

A heuristic path-estimating algorithm for large-scale real-time traffic information calculating

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Science china(Technological Sciences) 2008年第S1期51卷 165-174页

作者： L WeiFeng1,ZHU TongYu1,WU DongDong2,DAI Hong3.& HUANG Jian1 1 State Key Laboratory for Software Development Environment,Beihang University,beijing 100083.china 2 beijing Transportation Information {3.,beijing 100055,china 3.College of Arts & Science,beijing Union University,beijing 100083.china State Key Laboratory for Software Development Environment Beihang University Beijing China beijing Transportation Information center Beijing China College of Arts & Science Beijing Union University Beijing China

As the original Global Position System (GPS) data in Floating Car Data have the accuracy problem,this paper proposes a heuristic path-estimating algorithm for large-scale real-time traffic information calculating. It uses the heuristic search method,imports the restriction with geometric operation,and makes comparison between the vectors composed of the vehicular GPS points and the special road network model to search the set of vehicular traveling route candidates. Finally,it chooses the most optimal one according to weight. Experimental results indicate that the algorithm has considerable efficiency in accuracy (over 92.7%) and com-putational speed (max 8000 GPS records per second) when handling the GPS tracking data whose sampling rate is larger than 1 min even under complex road network conditions.

关键词： path-estimating floating car data (FCD) road network vector GPS

Implementation of a multiple round quantum dense coding using nuclear magnetic resonance

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Science china(Physics,Mechanics & Astronomy) 2005年第6期48卷 706-715页

作者： ZHANG Jingfu1, XIE Jingyi2, WANG Chuan1, DENG Zhiwei3. LU Zhiheng4, & LONG Guilu1,5 1. Key Laboratory For Quantum Information and Measurements of MOE, Department of Physics, Tsinghua University, beijing 100084,china 2. Department of Materials Science and Engineering, beijing Normal University, beijing 100875, china 3. Testing and Analytical center, beijing Normal University, beijing 100875,china 4. Department of Physics, beijing Normal University, beijing 100875, china 5. Key Laboratory For atomic and Molecular Nanosciences, Tsinghua University, beijing 100084,china Key Laboratory For Quantum Information and Measurements Department of Physics Tsinghua University Beijing 100084 China Department of Materials Science and Engineering Beijing Normal University Beijing 100875 China Testing and Analytical center Beijing Normal University Beijing 100875 China Department of Physics Beijing Normal University Beijing 100875 China Key Laboratory for Atomic and Molecular Nanosciences Tsinghua University Beijing 100084 China

A multiple round quantum dense coding scheme based on the quantum phase estimation algorithm is proposed and implemented in a three qubit nuclear magnetic resonance (NMR) quantum computer. Using an m + 1 qubit system, Bob can transmit one of 2m+1 messages to Alice, through manipulating only one qubit and exchanging it between Alice and Bob for m rounds. The information capacity is enhanced to m + 1 bits as compared to m bits in a classical scheme. The scheme has been demonstrated in NMR system, and the experimental results show a good agreement between theory and experiment.

关键词： quantum dense coding, multiple round, nuclear magnetic resorance

U-Pb dating of zircon from the bed parallel anatectic granitic intrusion in the Baoban group in Hainan Island and the tectonic implication

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Science china Earth Sciences 2005年第12期48卷 2092-2103页

作者： DING Shijiang1, HU Jianmin2, SONG Biao3.4, CHEN Mulun1, XIE Shengzhou1 & FAN Yuan1 1. Geological Surveying Institute of Hainan, Haikou 570206, china 2. Institute of Geomechanics, Chinese Academy of Geological Sciences, beijing 100081, china {3., beijing 10003., china 4. Institute of Geology, Chinese Academy of Geological Sciences, beijing 10003., china Geological Surveying Institute of Hainan Haikou China Institute of Geomechanics Chinese Academy of Geological Sciences Beijing China beijing center of shrimp Beijing China Institute of Geology Chinese Academy of Geological Sciences Beijing China

The petrological and geochemical features of the bed parallel granitic intrusion in the Pre-Cambrian Baoban group in Hainan Island attest to the anatexis origin of the granites. U-Pb dating analyses of zircons from the anatectic granite and the biotite two-feldspar gneiss in the Baoban group, using shrimp II in the beijing Ion-probe center, acquire 206Pb/23.U ages of 3.8±3.5 Ma (of granite, 95% confidence level, MSDW=1.23. and 3.2.9±6.1 Ma (of gneiss, 95% confidence level, MSDW = 2.04) respectively. The two late Devonian ages indicate consistently a tectonic- thermal event experienced in Hainan Island, and are the first discovered record of the Devonian geological process in the district. This event possibly resulted from the deep ther-mal-dynamic process when the Gondwana continent began to break up in the Devonian period.

关键词： Hainan Island, Devonian period, anatectic granite, zircon shrimp U-Pb dating.

Study on NDVI-T_s space by combining LAI and evapotranspiration

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Science china Earth Sciences 2006年第7期49卷 747-754页

作者： HAN Lijuan1,2,3. WANG Pengxin4, YANG Hua1,2,3. LIU Shaomin1,2,3.& WANG Jindi1,2,3.1. Research center for Remote Sensing and GIS, School of Geography, beijing Normal University, beijing 100875,{3. 2. State Key Laboratory of Remote Sensing Science, beijing 100875,{3. 3. beijing Key Laboratory for Remote Sensing of Environment and Digital Cities, beijing 100875,{3. 4. Department of Information Management, College of Information and Electronic Engineering,{3. Agricultural University, beijing 100083.{3. Research center for Remote Sensing and GIS School of Geography Beijing Normal University Beijing China State Key Laboratory of Remote Sensing Science Beijing China beijing Key Laboratory for Remote Sensing of Environment and Digital Cities Beijing China Department of Information Management College of Information and Electronic Engineering China Agricultural University Beijing China

This paper focuses on interpreting the different spatial relationships between NDVI and Ts, a triangular or a trapezoid, and on analyzing transformation conditions, the physical and ecological meanings of the vegetation index-surface temperature space as well. Further, we use the Tempera-ture-Vegetation Dryness Index (TVDI) to explain the existent meaning of a triangular space after NDVI reaches its saturated state by employing the relationships between NDVI, LAI and evapotranspiration. The specific relations between NDVI and Ts are useful for describing, validating and updating land surface models.

关键词： NDVI, land surface temperature, evapotranspiration, leave area index.

Exotic structure of the third excited state in^(21)Na

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Chinese Science Bulletin 2005年第23期50卷 2677-2680页

作者： LI Xihan1,2,3. LIANG Yujie1,2,3. DENG Fuguo1,2,3. LIU Zuhua1,4 & ZHOU Hongyu1,2,3.1. Key Laboratory of Beam Technology and Material Modification of Minister of Education, beijing Normal University, beijing 100875, china 2. Institute of Low Energy Nuclear Physics, and Department of Material Science and Engineering, beijing Normal University, beijing 100875, china 3. beijing Radiation center, beijing 100875, china 4. china Institute of Atomic Energy, beijing 102413. china Key Laboratory of Beam Technology and Material Modification of Minister of Education Beijing Normal University Beijing 100875 China Institute of Low Energy Nuclear Physics and Department of Material Science and Engineering Beijing Normal University Beijing 100875 China beijing Radiation center Beijing 100875 China china Institute of Atomic Energy Beijing 102413 China

The probability of the last proton being out of the binding potential, P and the root-mean-square (rms) ra- dius (1/2= of the third excited state in 21Na are calcu- lated by means of asymptotic normalization coefficient (ANC) method with the experimental date existing. The results are P=54.73. and 1/2=5.28 fm respectively. The P value and the contribution of the asymptotic part to the 1/2 are compared with those of several other low energy states in 21Na. It is found that the valence particle in the third excited state has an obvious larger P than those of other states. The density distribution of the valence proton in this state is also compared with the nucleons in the nuclear core 20Ne, and a far extended tail can be seen clearly. These results show that the third ex- cited state in 21Na is a proton halo state.

关键词：钠第三激发态外部结构有效半径密度分布渐近标准化系数

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. Graduate School of the Chinese Academy of Sciences, beijing 10003., china Engineering Research center for Information Security Technology Institute of Software Chinese Aca- demy of Sciences beijing Zhongke Ansheng Corporation of Information Technology Graduate School of the Chinese Academy of Sciences

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.