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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,Institute of Software,Chinese academy of sciences,Beijing 100190,{2. 2.graduate university of Chinese academy of sciences,Beijing 100049,{2. 1. State Key Laboratory of Information Security Institute of Software Chinese Academy of Sciences Beijing 100190 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 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

SHRIMP zircon U-Pb geochronology of early Mesozoic felsic igneous rocks from the southern Lancangjiang and its tectonic implications

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Science china Earth sciences 2006年第10期49卷 1032-1042页

作者： PENG Touping1,2. WANG Yuejun1, FAN Weiming1, LIU Dunyi3, SHI Yuruo3 & MIAO Laicheng4 1. Key Laboratory of Isotope Geochronology and Geochemistry, Guangzhou Institute of Geochemistry, Chinese academy of sciences, Guangzhou 510640, {2. 2. graduate university of Chinese academy of sciences, Beijing 100039, {2. 3. SHRIMP isotope Laboratory, Chinese academy of Geological sciences, Beijing 100037, {2. 4. Institute of Geology and Geophysics, Chinese academy of sciences, Beijing 10002., {2. Key Laboratory of Isotope Geochronology and Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China graduate university of Chinese {2. of sciences Beijing China SHRIMP isotope Laboratory Chinese Academy of Geological Sciences Beijing China Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China

The SHRIMP zircon U-Pb geochronology of three typical samples, including two monzo nitic granites from the Lincang batholith and a rhyolite from the Manghuai Formation are presented in the southern Lancangjiang, western Yunnan Province. The analyses of zircons for the biotite monzonitic granites from the northern (02.X-137) and southern (2.JH-10) Lincang batholith show the single and tight clusters on the concordia, and yield the weighted mean 2.6Pb/2.8U ages of 2.9.4 ± 3.0 Ma and 2.0.4 ± 3.6 Ma, respectively, representing the crystallized ages of these granites. The zircons for the rhyolitic sample (02.X-95) from the Manghuai Formation give a weighted mean 2.6Pb/2.8U age of 2.1.0 ± 5.0 Ma. These data suggest that the igneous rocks from the Lincang granitic batholith and Manghuai Formation have a similar crystallized age. In combination with other data, it is inferred that both were generated at a narrow age span (~2.0 Ma) and were originated from the postcollisional tectonic regime. An early Proterozoic 2.6Pb/2.8U apparent age of 1977±44 Ma is additionally obtained from one zircon from the biotite monzonitic granite (southern Lincang batholith), indicative of devel- opment of the early Proterozoic Yangtze basement in the region. These precisely geochronological data provide important constraints on better understanding the Paleozoic tectonic evolution of the Tethys, western Yunnan Province.

关键词： SHRIMP zircon U-Pb dating, Middle Triassic, Lincang granitic batholith, Manghuai Formation rhyolite, southern Lancangjiang.

Orbit determination and prediction accuracy analysis for a regional tracking network

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Science china(Physics,Mechanics & Astronomy) 2010年第6期53卷 1130-1138页

作者： ZHOU ShanShi 1,2.3 ,HU XiaoGong 1 & WU Bin 1 1 Shanghai Astronomical Observatory,Chinese academy of sciences,Shanghai 2.0030,{2. 2.graduate university of Chinese academy of sciences,Beijing 100049,{2. 3 Research Center of GNSS,Wuhan 430079,{2. 1. Shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai 200030 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China3. Research Center of GNSS Wuhan 430079 China

china's COMPASS satellite navigation system relies on a regional tracking network to provide navigation services. Limited by its geographic border,the regional network is able to cover only 30% of the medium-earth-orbits(MEO). Accuracy of determined and predicted orbits is not able to satisfy system requirements if the tracking data processing strategy for global tracking network processing is used for the regional network. Two major error sources for orbital prediction are accuracy of initial orbital elements and dynamical modeling. To achieve better prediction accuracy,we propose a two-step orbit determination and prediction strategy. For step 1,only solar radiation pressure(SRP) parameters are estimated along with the orbital elements and other parameters; for step 2.all parameters are estimated but the SRP parameters are tightly constrained to their step 1 estimates. Experimenting with data from a regional GPS network,we conclude for orbital prediction using the proposed two-step strategy,the average user range error(URE) for 2.-h prediction arcs is better than 0.6 m.

关键词： orbit determination and prediction regional tracking network URE

A two-round honest-verifier zero-knowledge protocol

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Science china(Information sciences) 2010年第5期53卷 954-963页

作者： LIU HanWu 1,2.& LIN DongDai 1 1 The State Key Laboratory of Information Security, Institute of Software, Chinese academy of sciences, Beijing 100190, {2. 2.graduate university of the Chinese academy of sciences, Beijing 100049, {2. 1. The State Key Laboratory of Information Security Institute of Software Chinese Academy of Sciences Beijing 100190 China2. Graduate University of the Chinese Academy of Sciences Beijing 100049 China

Since the concept of zero-knowledge protocols was introduced, it has attracted a lot of attention and in turn showed significant effect on the development of cryptography, complexity theory and other areas. The round complexity of a zero-knowledge protocol is a very important efficiency consideration, and it is required to be as small as possible. Generally, it is desirable to have zero-knowledge protocols with constant numbers of rounds. Goldreich and Oren proved that only languages in BPP have one-round and two-round zero-knowledge protocols. Moreover, they also showed that only languages in BPP have one-round honest-verifier zero-knowledge protocols. The notion of honest-verifier zero-knowledge protocols is highly non-trivial and fascinating itself, and has many other uses. Thus, the problem as to whether there exist two-round honest-verifier zero-knowledge protocols becomes an important open problem. In this paper, we introduce a new simulation technique and present a two-round honest-verifier zero-knowledge protocol for any language in N P under a standard complexity assumption based on this technique.

关键词： proof system argument system zero-knowledge witness indistinguishability black-box one-way permutation commitment scheme zap

The gravitational gradient tensor’s invariants and the related boundary conditions

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Science china Earth sciences 2010年第5期53卷 781-790页

作者： YU JinHai1,2.3 & ZHAO DongMing4 1 College of Earth Science, graduate university of Chinese {2. of sciences, Beijing 100049, china 2.Institute of Geodesy and Geophysics, Chinese {2. of sciences, Wuhan 430077, china 3 State Key Laboratory of Astronautic Dynamics, Xi’an 710043, china 4 Zhengzhou Institute of Surveying and Mapping, Zhengzhou 450052. china 1. College of Earth Science Graduate University of Chinese Academy of Sciences Beijing 100049 China2. Institute of Geodesy and Geophysics Chinese Academy of Sciences Wuhan 430077 China3. State Key Laboratory of Astronautic Dynamics Xi’an 710043 China4. Zhengzhou Institute of Surveying and Mapping Zhengzhou 450052 China

Here we report new approaches of recovering the Earth gravitational field from GOCE (Gravity field and steady-state Ocean Circulation Explorer) gradiometric data with the help of the gradient tensor’s invariants. Our results only depend on GOCE satellite’s position and gradiometry, in other words, they are completely independent of the satellite attitude. First, starting from the invariants, linearization models are established, which can be referred as the general boundary conditions on the satellite’s orbit. Then, the spherical approximation expressions for the models are derived, and the corresponding solving methods for them are discussed. Furthermore, considering effects of J2.term, the spherical approximation models are improved so that the accuracies of the boundary conditions can be theoretically raised to O ( J 2.2.T), which is approximately equivalent to O(T2.. Finally, some arithmetic examples are constructed from EGM96 model based on the derived theories, and the computational results illustrate that the spherical models have accuracies of 10-7 and the order recovering the gravitational field can reach up to 2.0, and the models with regard to effect of J2.term have accuracies of 10-8 and the order can reach up to 2.0.

关键词： the Earth’s gravitational field gravitational gravidiometry tensor’s invariant

Optimization of mathematical models for thematic maps

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Science china(Technological sciences) 2010年第S1期53卷 15-24页

作者： QI QingWen1,ZHANG An1,JIANG LiLi1,ZOU XiuPing2.XU Li3 & CHENG Xi1,4 1 Institute of Geographical sciences and Natural Resources Research,Chinese academy of sciences,Beijing 100101,china 2.Institute of Policy and Management,Chinese academy of sciences,Beijing 100080,china 3 Taishan university,Taian 2.102.,china 4 graduate university of Chinese academy of sciences,Beijing 100049,china Chinese Acad Sci Inst Geog Sci & Nat Resources Res Beijing 100101 Peoples R China Chinese Acad Sci Inst Policy & Management Beijing 100080 Peoples R China Taishan Univ Tai An 271021 Shandong Peoples R China Chinese Acad Sci Grad Univ Beijing 100049 Peoples R China

The thematic map is a major class of maps designed to demonstrate particular features or concepts,functioning as an indispensable tool in geographical *** process of thematic mapping is one into which geographical research goes deeply and *** key activity and course of thematic map production is the use of mathematical models to create thematic data ***,the selection and optimization of mathematical models is in the forefront of thematic map *** theoretical foundations,mechanisms and methods of mathematical model optimization are expounded in this paper,including two approaches,the phase by phase mode and the multi-aim scheme balance *** studies in eco-environment mapping and emergency mapping are described and analyzed,with a hierarchical analysis method being used in the model optimization for eco-environment fragility and sensitivity assessment mapping in Beibuwan (Guangxi) District,the dynamic system (DS) method being used in the model optimization for ecological security adjustment mapping in Xishuang Banna,Yunnan province,and the multi-phase mode being used in the models for forest fire and infectious diseases mapping.

关键词： thematic map mathematic model optimization

Positive Darwinian selection in human population:A review

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Chinese Science Bulletin 2008年第10期53卷 1457-1467页

作者： WU DongDong1,3 & ZHANG YaPing1,2.1 State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese academy of sciences, Kunming 6502.3, {2. 2.Laboratory for Conservation and Utilization of Bio-resource, Yunnan university, Kunming 650091, {2. 3 graduate university of Chinese academy of sciences, Beijing 100049, {2. State Key Laboratory of Genetic Resources and Evolution Kunming Institute of Zoology Chinese Academy of Sciences Kunming 650223 China Laboratory for Conservation and Utilization of Bio-resource Yunnan University Kunming 650091 China graduate university of Chinese {2. of sciences Beijing 100049 China

This paper reviews a large number of genes under positive Darwinian selection in modern human populations, such as brain development genes, immunity genes, reproductive related genes, perception receptors. The research on the evolutionary property of these genes will provide important insight into human evolution and disease mechanisms. With the increase of population genetics and comparative genomics data, more and more evidences indicate that positive Darwinian selection plays an indispensable role in the origin and evolution of human beings. This paper will also summarize the methods to detect positive selection, analyze the interference factors faced and make suggestions for further research on positive selection.

关键词：自然选择积极选择达尔文进化论人类学种群遗传

Genomic organization and sequence analysis of the vomeronasal receptor V2. genes in mouse genome

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Chinese Science Bulletin 2007年第3期52卷 336-342页

作者： YANG Hui1,2.& Zhang YaPing1,3 1 Laboratory of Cellular and Molecular Evolution, Kunming Institute of Zoology, Chinese academy of sciences, Kunming 6502.3, {2. 2.graduate university of the Chinese academy of sciences, Beijing 100049, {2. 3 Laboratory for Conservation and Utilization of Bio-resources, Yunnan university, Kunming 650091, {2. Laboratory of Cellular and Molecular Evolution Kunming Institute of ZoologyChinese Academy of Sciences Kunming 650223 China

Two multigene superfamilies, named V1R and V2., encoding seven-transmembrane-domain G-protein coupled receptors (GPCRs) have been identified as pheromone receptors in mammals. Three V2. gene families have been described in mouse and rat. Here we screened the updated mouse genome se- quence database and finally retrieved 63 putative functional V2. genes including three newly identified genes which formed a new additional family. We described the genomic organization of these genes and also characterized the conservation of mouse V2. protein sequences. These genomic and se- quence information we described are useful as part of the evidence to speculate the functional domain of V2.s and should give aid to the functionality study in the future.

关键词：大白鼠基因组犁鼻受体2 多基因超家族序列分析

An efficient chiral synthesis of (R)-N-[3-acetyl-4-(2.hydroxy-3-isopropylamino-propoxy)phenyl]-butanamide with high enantioselectivity

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Science china Chemistry 2009年第8期52卷 1216-1219页

作者： WANG NaiXing1,2.& TANG XinLiang1,3 1 Technical Institute of Physics and Chemistry,Chinese academy of sciences,Beijing 100080,{2. 2.College of Chemistry and Chemical Engineering,graduate university of Chinese academy of sciences,Beijing 100049,{2. 3 School of Chemical Engineering and Environment,Beijing Institute of Technology,Beijing 100081,{2. 1. Technical Institute of Physics and Chemistry Chinese Academy of Sciences Beijing 100080 China 2. College of Chemistry and Chemical Engineering Graduate University of Chinese Academy of Sciences Beijing 100049 China 3. School of Chemical Engineering and Environment Beijing Institute of Technology Beijing 100081 China

R-Enantiomer of the β-receptor antagonist N-[3-acetyl-4-(2.hydroxy-3-isopropylamino-propoxy)phenyl] butanamide with high enantioselectivity was synthesized from cheap starting materials and enantiopure chiral reagent through an efficient,convenient and practical synthetic *** product was detected by 1H NMR,13C NMR,and MS,and the enatiomeric excess was determined by chiral HPLC analysis using a chiracel AD-H column.

关键词： chiral synthesis enantioselectivity enatiomeric excess chiral HPLC analysis