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CMQV+:An authenticated key exchange protocol from CMQV

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Science china(Information sciences) 2012年第7期55卷 1666-1674页

作者： LI Hui 1,2.& WU ChuanKun 1 1 State key laboratory of Information Security,{2. of Software,chinese 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

Ustaoglu presents a secure and efficient key exchange protocol named CMQV,based on the design rationales of HMQV and *** with the latter two protocols,on one hand,CMQV achieves high performance of HMQV,and on the other,it is proven secure in eCK model as NAXOS ***,CMQV enjoys the security proof under gap Diffie-Hellman assumption as indicated by its *** this paper,we propose a variant of CMQV,called CMQV+,which is proven secure under a weaker assumption (*** Diffie-Hellman assumption) in eCK model with random oracles while maintaining the high-performance feature of CMQV as much as possible.

关键词： key exchange eCK model trapdoor-test technique provable security CDH assumption

Dynamic tree-based authenticated group key exchange protocol

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Science china(Information sciences) 2010年第8期53卷 1591-1602页

作者： LI Hui 1,2., WU ChuanKun 1 & TENG JiKai 1,2.1 State key laboratory of Information Security, {2. of Software, chinese 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

Authenticated group key exchange protocols allow a group of users over a public network to establish a shared secret key for the subsequent cryptographic goals. In this paper, we extend BD-II scheme into a dynamic setting, and propose a tree-based authenticated key exchange protocol which is more suitable for dynamic groups in such as ad hoc networks. Our protocol is proven secure in random-oracle model. Additionally, we analyze the costs of our protocols in both communication and computation terms, and compare its performance with three well-known protocols.

关键词： tree-based group key exchange dynamic provable security

The consideration and choice on exploiting energy source

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chinese Science Bulletin 1999年第18期44卷 1717-1728页

作者： WANG XianbinState key laboratory of {2. geochemistry, lanzhou institute of Geology, chinese academy of sciences , lanzhou 73.000, china State key laboratory of {2. geochemistry Lanzhou Institute of Geology Chinese Academy of Sciences Lanxhou China

A problem of petroleum energy crisis will probably be faced in the late 2.st century. It is impossible to discover the giant oil fields again based on the traditional knowledge and theory of petroleum geology. From the global development point of view as well as the situation in china, the five choices of energy source in the future are to ( i ) extend the field of exploration in conventional petroleum and natural gas source, and exploit oil-gas source in ocean and

关键词： energy sources in the future unconventional gas coal hydrogen controllable nuclear fusion 3He source on the moon.

Characteristics and origins of primary fluids and noble gases in mantle-derived minerals from the Yishu area,Shandong Province,china

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Science china Earth sciences 2006年第1期49卷 77-87页

作者： MA Jinlong1,2. TAO Mingxin2.3 & YE Xianren2.1. Resources and Environmental School, lanzhou University, lanzhou 73.000,{2. 2. key laboratory of gas geochemistry, institute of Geology and geophysics, chinese academy of sciences, lanzhou 73.000,{2. 3. College of Resources Science & Technology, Beijing Normal University, Beijing 100875,{2. Resources and Environmental School Lanzhou University Lanzhou China key laboratory of {2. geochemistry Institute of Geology and Geophysics Chinese Academy of Sciences Lanzhou China College of Resources Science & Technology Beijing Normal University Beijing China

Fluids and noble gases of mantle-derived materials are important tracers forthe mantle information. Compositions of primary fluids and noble gases in mantle-derived mineralsfrom the Yishu area, Shandong Province,{2., were tested by the methods of heat-bursting andheat-melting respectively. The fluids are mainly composed of CO_2. CO and H_2. which account forabout 90% of the total, and are similar to the mantle-derived rocks from other areas of easternchina; ratios of ~3He/~4He in almost all samples range from 0.82.Ra to 2.74 Ra, whereas^(40)Ar/^(36)Ar from 2.9.5 to 758.8. Both ranges are much lower than those of the typical oceanmantle-derived samples (such as MORB) and primarily reflect the influences of the atmosphericcomponents and the radiogenic isotopes. Ratios of C/~3He range from 2..6 x 10~9 to 1050 x 10~9,N_2.Ar from 92. to 56612. and N_2.~3He from 2.5 x 10~9 to 2. x 10~9, similar to those in westernUnited States and New Zealand which belong to the tectonic plate collision regions. The ratios fallin the intersect of mantle-crust-atmosphere in the comprehensive tracer-charts, reflecting theinfluences of the atmosphere and the crusts with organic components. Our results suggest that thecomposition of the primary fluids and the isotopic ratios of the noble gases may either reflect theevolution process of mantle-derived rocks connected with the rise and eruption of magma, or theinfluence of the ancient subduction-plate on the continental mantle of this region.

关键词： noble gases, primary fluids, mantle-derived minerals, Yishu area.

Research progress in studies on the coalbed gas geochemistry

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Progress in Natural Science:Materials International 2006年第3期16卷 215-220页

作者： TAO Mingxin (College of Resources sciences & Technology, Beijing Normal University, Beijing 100875, china {2. laboratory of gas geochemistry, institute of Geology and geophysics, chinese academy of sciences, lanzhou 73.000, china) College of Resources sciences and Technology Beijing Normal University Beijing 100875 China key laboratory of {2. geochemistry Institute of Geology and Geophysics Chinese Academy of Sciences Lanzhou 730000 China

The current situation of geochemical studies on coalbed gas is reviewed in this paper. Generally, coalbed gas is composi-tionally dominated by methane with δ13C1 values ranging approximately from - 80‰ to - 10‰. However, few isotopic studies have been carried out on other components of coalbed gas except for hydrogen and carbon dioxide, whose δDCH4 values available for utilization vary from - 333‰ to - 117‰, and δ13CCO2.values from - 2.. 4‰ to + 18. 6‰. Two major types of coalbed gas, thermogenic gas and secondary biogenic gas, have been identified, and there are also some other classification criteria. Compared with conventional natural gases, coalbed gas has a wide distribution range of δ13C1 and δ13CCO2.values, especially possessing some extremely heavy values. Current problems that remain unsolved in the coalbed gas geochemistry include the variation mechanism, controlling factors and application of carbon and hydrogen isotopes of methane, the relation between the values of δ13C1 and Ro, the systematic classification scheme and criterion of genetic types, and the application of the coalbed gas geochemistry in evaluating target districts of the coalbed gas exploration.

关键词： coalbed gas geochemistry isotopic composition genetic type novel resource.

Magnetic properties of Jiaxian red clay sequences from northern chinese Loess Plateau and its paleoclimatic significance

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Science china Earth sciences 2005年第8期48卷 1234-1245页

作者： QIANG Xiaoke, AN Zhisheng, LI Huamei, CHANG Hong & SONG Yougui 1. SKLLQG, institute of Earth Environment, chinese academy of sciences, Xi’an 710075,{2. 2. Guangzhou institute of geochemistry, chinese academy of sciences, Guangzhou 510640,{2. chinese academy of {2. SKLLQG Institute of Earth Environment Xi’an China chinese academy of {2. Guangzhou Institute of Geochemistry Guangzhou China

Detailed rock magnetism investigation of the Jiaxian red clay sequences indicated that there are common magnetic mineralogy properties in red clay and loess-paleosol sequences from the chinese Loess Plateau as well as the marked properties of themselves, magnetic min-erals mainly with magnetite, maghemite, hematite, and possibly limonite/goethite contributing to the magnetic behavior. Meanwhile, it is found that the strong paleosol in red clay sequences has a lower coercivity and higher content of ultra-fine ferrimagnetic grains than that of the weak pa-leosol, which is similar to loess and paleosol in upper Wucheng Loess sequences, and indicates that humid conditions and relatively strong pedogenesis play a significant role in the increase of ultra-fine magnetic minerals and transformation of the magnetic minerals. This suggests that, like Quaternary loess-paleosols, the change of characteristics of paleoclimatic conditions of the late Tertiary red clay deposits is fluctuant. In addition, the results of magnetic hysteresis properties show that the applied saturated field for samples from the Jiaxian red clay sequences is higher than that of the samples from eastern and southern chinese Loess Plateau. It is obviously shown that there exist more hard magnetic minerals and relatively weak biochemical processes in the Jiaxian red clay sequences on northern chinese Loess Plateau. We conclude that the paleocli-matic environment is different between northern and eastern/southern chinese Loess Plateau, and it should be more arid in northern chinese Loess Plateau.

关键词： northern chinese Loess Plateau, red clay, magnetic property, paleoclimatic significance.

Expression and purification of lipoprotein-associated phospholipase A2.a key enzyme involved in atherosclerosis

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Acta Pharmacologica Sinica 2006年第6期27卷 679-684页

作者： Fu-jun ZHANG~(2.4)Mao-jun CAI~3 Jing-kang SHEN~3 Yi-ping WANG~(2.5)2.State key laboratory of Drug Research.3 Department of Medicinal Chemistry,Shanghai {2. of Materia Medica,Shanghai {2.s for Biological sciences,chinese academy of sciences.Shanghai 2.12.3,china 4 Graduate School of the chinese academy of sciences.chinese academy of sciences,Shanghai 2.12.3.china State key laboratory of Drug Research Chinese Academy of Sciences Shanghai China Graduate School of the chinese academy of sciences Chinese Academy of Sciences Shanghai China Department of Medicinal Chemistry Shanghai Institute of Materia Medica Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai China

Aim:To express and purify lipoprotein-associated phospholipase A2.Lp-PLA2.,and to establish a screening model for Lp-PLA2.nhibitors using the expressed Lp-PLA2.Methods:We cloned the full-length cDNA of Lp-PLA2.from differentiatedTHP-I cells,and subcloned the cDNA into the baculovirus transfer *** addition,we introduced an N-terminal Kozak sequence for high-level translation initiation and a C-terminal sequence of 6 histidine residues forpurification,The fusion enzyme was expressed in Sf9 insect cells and purified byNi2.affinity *** Lp-PLA2.ctivity was measured us-ing[3H]PAF as a substrate,and we examined the enzyme activity of recombinantLp-PLA2.retreated with the known Lp-PLA2.nhibitor ***:Wesuccessfully cloned the full-length Lp-PLA2.ene from differentiated THP-1 *** fusion enzyme was expressed in Sf9 insect cells at a high level and purifiedefficiently through a 2.step *** recombinant Lp-PLA2.ctivity wasmeasured using[3H]PAF as a substrate,and proved to be enzymatically ***-PLA2.nhibitor SB435495 produced a good inhibition curve for inhibition ofrecombinant Lp-PLA2.ith an IC50of 57±1μmol/***:We expressed andpurified Lp-PLA2.t a high level in insect cell-baculovirus expression *** ratio was much greater than that obtained from human plasma and we estab-lished a screening model for Lp-PLA2.nhibitors using the expressed Lp-PLA2.

关键词： lipoprotein-associated phospholipase A2 atherosclerosis coronary heart diseases cloning baculovirus purification

Characteristics and geological significance of olivine xenocrysts in Cenozoic volcanic rocks from western Qinling

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Progress in Natural Science:Materials International 2006年第12期16卷 1300-1306页

作者： SU Benxun~ 1,2.**, ZHANG Hongfu~1, XIAO Yan~ 1,2.and ZHAO Xinmiao~ 1,2.(1. State key laboratory of Lithospheric Evolution, {2. of Geology and geophysics, chinese academy of sciences, Beijing 10002., china 2. Graduate School of chinese academy of sciences, Beijing 100039, china) State key laboratory of Lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China Graduate School of chinese academy of sciences Beijing 100039 China

Cenozoic volcanic rocks from the Haoti, Dangchang County of the western Qinling Mountains, contain a few clearly-zoned olivines. These olivines are relatively big in grain sizes and usually have cracks or broken features. Their cores have similar compositions （Mg#=90.4-91.0） to those for the peridotitic xenoliths entrained in host volcanic rocks and their rims are close to the compositions of olivine phenocrysts （Mg#=85.5-81.9）. The CaO contents in these zoned olivines are lower than 0.1%. These features demonstrate that the clearly-zoned olivines are xenocrysts and disaggregated from mantle peridotites. The zoned texture was the result of the interaction between the olivine and host magma. Available data show that the volcanic rocks would have been derived from the mantle source metasomatized by subducted hydrathermally-altered oceanic crust. The formation of these Cenozoic volcanic rocks was perhaps related to the rapid uplift of the Tibetan Plateau.

关键词： Western Qinling Dangchang Haoti Cenozoic volcanic rocks olivine xenocrysts zoned texture.

Analysis and application of automatic deformation monitoring data for buildings and structures of mining area

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中国有色金属学会会刊：英文版 2011年第S3期21卷 516-522页

作者： XIAO Jie1, 2. 3, ZHANG Jin4 1. institute of Geodesy and geophysics,{2., Wuhan 430077, china 2. key laboratory of Dynamic Geodesy, institute of Geodesy and geophysics,{2., Wuhan 430077, china 3. Graduate School of{2., Beijing 100049, china 4. Department of Surveying and Mapping, Taiyuan University of Technology, Taiyuan 03002., china institute of Geodesy and geophysics Chinese Academy of Sciences Wuhan 430077 China key laboratory of Dynamic Geodesy Institute of Geodesy and Geophysics Chinese Academy of Sciences Wuhan 430077 China Graduate School of chinese academy of sciences Beijing 100049 China Department of Surveying and Mapping Taiyuan University of Technology Taiyuan 030024 China

The buildings and structures of mines were monitored automatically using modern surveying technology. Through the analysis of the monitoring data, the deformation characteristics were found out from three aspects containing points, lines and regions, which play an important role in understanding the stable state of buildings and structures. The stability and deformation of monitoring points were analysed, and time-series data of monitoring points were denoised with wavelet analysis and Kalman filtering, and exponent function and periodic function were used to get the ideal deformation trend model of monitoring points. Through calculating the monitoring data obtained, analyzing the deformation trend, and cognizing the deformation regularity, it can better service mine safety production and decision-making.

关键词： wavelet analysis Kalman filtering deformation monitoring data analysis mine