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Chinese science Bulletin 2001年第4期46卷 322-325页

作者： LIU Yongjiang, YE Huiwen, GE Xiaohong, chen Wen, LIU Junlai, REN Shoumai & PAN HongxunCollege of Earth sciences, Changchun university of science and technology, Changchun 130061, china.graduate school, china.university of Geosciences, beijing 100083, china.Laboratory of Isotopic Geochronology, Institute of Geology, Ministry of Land and Resources of china. beijing 100037, china College of Earth sciences Changchun University of Science and Technology Changchun China graduate school China University of Geosciences Beijing China Laboratory of Isotopic Geochronology Institute of Geology Ministry of Land and Resources of China Beijing China

The samples of Caledonian mylonitized granite and Jurassic meta-sedimentary rocks were collected in the north of Dangjinshan Pass, Qaidam gate fault-valley and Gesi fault-valley. Detailed studies under the microscope and electronic microscope suggest that all the samples contain the syntectonic-growing minerals such as white mica, chlorite, sericite, biotite, etc. By dating these minerals, we got a group of 40Ar/39Ar laser probe isochronal ages of 89-92 Ma and apparent ages of (46.6±6.4) Ma. The ages ranging from 97 to 46 Ma were reported for the first time in the isotopic dating researches of the Altyn Fault The isochronal age group of (98-89) Ma indicates that a ductile strike-slip event, with low-grade metamorphism, began in late Cretaceous. This suggests that the strike-slip movement of the Altyn Fault should be related to the formation of the so-called west tectonic syntaxis in the Nepal-western Kunlun area.

关键词： Altyn Fault 40Ar/39Ar age strike-slip movement.

Identification and removal of block ambiguities in sea surface wind field with scatterometers

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science china.Earth sciences 2009年第2期52卷 242-249页

作者： chen KeHai1,2, XIE XueTong3 & FANG Yu4 1 South china.Sea Institute of Oceanology, Chinese Academy of sciences, Guangzhou 510301, china.2 graduate university of Chinese Academy of sciences, beijing 100049, china.3 school of Electronic science and Engineering, National university of Defense technology, Changsha 410073, china.4 The Institute of Remote Sensing and GIS, Peking university, beijing 100871, china 1. South china.Sea Institute of Oceanology Chinese Academy of Sciences Guangzhou 510301 China 2. graduate university of Chinese Academy of sciences Beijing 100049 China 3. school of Electronic science and Engineering National University of Defense Technology Changsha 410073 China 4. The Institute of Remote Sensing and GIS Peking University Beijing 100871 China

The solution of the current wind retrieval algorithm for scatterometers has several wind vector ambi-guities, due to the bi-harmonic relationship between normalized backscattering cross section and the relative wind direction and the existence of the measurement error. In order to remove the ambiguities for a unique wind field, a circular median filter approach (CMF) is usually adopted. But under the con-dition for clustering distribution of the false ambiguities in some local areas, the CMF fails and thus engenders block ambiguities, which degrade the precision of the retrieved wind field. For such a situation, a technique of identification and removal of the block ambiguities is presented to further optimize the retrieved wind field after CMF. It is demonstrated in experiment that this technique can identify and remove most of the block ambiguities.

关键词： scatterometer block ambiguity identification and removal

Recent progress in fingerprint recognition

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Progress in Natural science:Materials International 2006年第3期16卷 231-240页

作者： TIAN Jie, chen Xinjian, ZHANG Yangyang, YANG Xin, HE Yuliang, LI Liang, XIE Weihua and ZHENG Zhipeng (Center for Biometrics and Security Research, Key Laboratory of Complex Systems and Intelligence science, Institute of Automation, Chinese Academy of sciences, beijing 100080, china.graduate school of the Chinese Academy of sciences, beijing 100080, china. [a]Center for Biometrics and Security Research Key Laboratory of Complex Systems and Intelligence Science Institute of Automation Chinese Academy of Sciences Beijing China [b]graduate school of the Chinese Academy of sciences Beijing China

Fingerprint recognition has been increasingly used to realize personal identification in civilian' s daily life, such as ID card, fingerprints hard disk and so on. Great improvement has been achieved in the on-line fingerprint sensing technology and automatic fingerprint recognition algorithms. Various fingerprint recognition techniques, including fingerprint acquisition, classification, enhancement and matching, are highly improved. This paper overviews recent advances in fingerprint recognition and summarizes the algorithm proposed for every step with special focuses on the enhancement of low-quality fingerprints and the matching of the distorted fingerprint images. Both issues are believed to be significant and challenging tasks. In addition, we also discuss the common evaluation for the fingerprint recognition algorithm of the Fingerprint Verification Competition 2004 (FVC2004) and the Fingerprint Vendor technology Evaluation 2003 (FpVTE2003), based on which we could measure the performance of the recognition algorithm objectively and uniformly.

关键词： biometrics fingerprint enhancement matching minutia image registration similarity measures.

Effect of sediment resuspension on underwater light field in shallow lakes in the middle and lower reaches of the Yangtze River:A case study in Longgan Lake and Taihu Lake

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science china.Earth sciences 2006年第z1期49卷 114-125页

作者： ZHANG Yunlin, QIN Boqiang, ZHU Guangwei, GAO Guang, LUO Liancong & chen Weimin Nanjing Institute of Geography & Limnology, Chinese Academy of sciences, Nanjing 210008, china.graduate school of Chinese Academy of sciences, beijing 100039, china 1. Nanjing Institute of Geography & Limnology Chinese Academy of Sciences Nanjing 210008 China 2. graduate school of Chinese Academy of sciences Beijing 100039 China

Based on three continuous in situ underwater light field measurement under different wind waves conditions in Longgan Lake, Meiliang Bay of Taihu Lake in July 2003 and littoral zone near TLLER in July 2004, respectively, the effects of sediment resuspension caused by wind waves on PAR diffuse attenuation, absorption coefficients and euphotic depths are analyzed. In Longgan Lake, PAR diffuse attenuation coefficients during small, middle and large wind waves were 1.74, 2.02 and 2.45 m-1, respectively, and the corresponding PAR spectral diffuse attenuations ranged from 0.98 to 2.97, 1.34 to 3.95 and 1.80 to 5.40 m-1, respectively. In Meiliang Bay, PAR diffuse attenuation coefficients were 2.63, 3.72, 4.37 m-1 during small, middle and large wind waves. PAR diffuse attenuation coefficients increased by 41% and 66% from small to middle, large wind waves, respectively. Absorption coefficients integrated over the range of PAR of CDOM, phytoplankton were 0.26, 0.28 m-1; 0.76, 0.49 m-1, respectively during middle and large wind waves. Absorption coefficients integrated over the range of PAR of non-algal particulate matter and total suspended particulate matter increased from 0.94 to 1.73 m-1, and from 1.70 to 2.22 m-1, respectively during middle and large wind waves. Relative contributions of absorption coefficients of non-algal particulate matter to total absorption coefficient integrated over the range of PAR were 44.14%, 65.05%, respectively, during middle and large wind waves. PAR euphotic depths decreased by 0.40, 0.19, 0.20 m from middle to large wind waves in Longganhu Lake, Meliang Bay and littoral zone near TLLER. Significant correlations were found between transparency, PAR diffuse attenuation coefficients, euphotic depths and total suspended paniculate matter, wind velocity, wave height. Most significant correlations were found between transparency, PAR diffuse attenuation coefficients, euphotic depths and inorganic suspended paniculate matter but low correlations

关键词： shallow lake, Taihu Lake, diffuse attenuation coefficient, absorption coefficient, total suspended particulate matter.

Properties of the 3/2^-[521] band in the odd-N rare-earth nuclei

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science china.Physics,Mechanics & Astronomy) 2011年第S1期54卷 37-43页

作者： chen Liang1,2, ZHOU XiaoHong1,2, ZHANG YuHu1, ZHANG ShuangQuan3 & ZHU LiHua4 1Institute of Modern Physics, Chinese Academy of sciences, Lanzhou 730000, china.2graduate university of Chinese Academy of sciences, beijing 100049, china.3State Key Laboratory of Nuclear Physics and technology, school of Physics, Peking university, beijing 100871, china.4china.Institute of Atomic Energy, beijing 102413, china 1. Institute of Modern Physics Chinese Academy of Sciences Lanzhou 730000 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China3. State Key Laboratory of Nuclear Physics and Technology School of Physics Peking University Beijing 100871 China4. China Institute of Atomic Energy Beijing 102413 China

High-spin states in 161Er have been studied experimentally via the 150Nd(16O, 5n) reaction at a beam energy of 86 MeV. Three rotational bands built on the 5/2+[642], 3/2-[521], and 11/2-[505] configurations have been extended up to high-spin states, and particularly, the α = -1/2 branch of the ground state 3/2-[521] band has been revised significantly. It is found that signature inversion occurs in the 3/2-[521] band after the band crossing in 161Er. The systematics of the signature inversion associated with the 3/2-[521] configuration in the rare-earth region is discussed. The band properties are analyzed within the framework of a triaxial particle-rotor model, and a triaxial deformation is proposed to the 3/2-[521] band.

关键词： high-spin states signature inversion triaxial particle-rotor model

INFERENCE IN A SIMPLE CHANGE-POINT MODEL

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science in china.Ser.A 1988年第6期 654-667页

作者：陈希孺 graduate school university of science and technology of china beijing

For the change-point model allowing at most one change X（i/n）=f（i/n）+e（i/n）, where f（t）=α+θI(（t0,1]）（t）, O≤t≤1, e（1/n）,…, e（n/n） are independently and identically distributed, the problem of testing and interval estimation about the change-point t0, the magnitude of jump θ and the variance σ2 of random error e（t）, is considered.

关键词： INFERENCE IN A SIMPLE CHANGE-POINT MODEL

Mapping the Farming-pastoral Ecotones in china

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Journal of Mountain science 2009年第1期6卷 78-87页

作者： ZHANG Jian WEI Jie chen Quangon Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu 610041 China Tourism College Chongqing Normal University Chongqing 400047 China school of PastoralAgricultural science and technology Lanzhou University Lanzhou 730020 China graduate university of the Chinese Academy of sciences Beijing 100049 China

Conventional farming-pastoral ecotones methods of delineating were not quantitative and could not fully show their spatial distribution. The present paper attempts to develop quantitative methods for mapping farming-pastoral ecotones in china. Nine indicators, related to temperature, precipitation and altitude aspects, were selected to quantify ecological susceptibility of vegetation （crops and forage）. Methods of analytic hierarchy process （AHP） and expert score ranking combined with fuzzy set theory were applied to assign the weight for each indicator and to define the membership functions. The geographic information system （GIS） was used to manage the spatial database and conduct the spatial analysis. According to the spatial calculation of evaluation model integrated with GIS, the ecological susceptibility of vegetation （crops and forage） was mapped. Three different zones, pastoral area, farming-pastoral ecotones and farming area, were classified by spatial cluster analysis and the maximum likelihood classification for the numeric map of vegetation ecological susceptibility by GIS. This map was validated by the economic statistical result based on the ratio of the output value from animal husbandry in total output value of agriculture by the National Bureau of Statistics in china. indicating that the mapping of the farming-pastoral ecotones may be accepted.

关键词： AHP Farming-pastoral ecotone Fuzzyset theory GIS

Effect of Fe metal on the growth of silicon oxide nanowires

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International Journal of Minerals,Metallurgy and Materials 2009年第3期16卷 317-321页

作者： Wei-long Liu1), Shu-huei Hsieh1), Ching He chen2), and Wen-jauh chen3) 1) Department of Materials science and Engineering, Formosa university, Yunlin 632, china.Taipei 2) Department of Materials Engineering, Pingtung university of science and technology, Pingtung 912, china.Taipei 3) graduate school of Materials science, Yunlin university of science and technology, Yunlin 632, china.Taipei [a]Department of Materials science and Engineering Formosa University Yunlin 632 China Taipei [b]Department of Materials Engineering Pingtung University of Science and Technology Pingtung 912 China Taipei [c]Graduate School of Materials Science Yunlin University of Science and Technology Yunlin 632 China Taipei

Silicon oxide (SiOx) nanowires are generally grown on Si substrate under the catalysis of Au in N2 atmosphere at elevated temperatures. Because the price of Au metal is quite high, Fe metal is then used to replace a part of Au for catalyzing the growth of SiOx nanowires. The results show that the Fe film can be used as the diffusion barrier of Au. SiOx nanowires are grown on Au/Fe/Si substrate at 1030°C. Under the catalysis of Fe/Au, the efficiency for the growth of SiOx nanowires is promoted.

关键词： silicon oxide nanowires Au catalyst Fe substitution Si substrate

Accountable authority key policy attribute-based encryption

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science china.Information sciences) 2012年第7期55卷 1631-1638页

作者： WANG YongTao 1,2 ,chen KeFei 1,3 ,LONG Yu 1,4 & LIU ZhaoHui 2 1 Department of Computer science and Engineering,Shanghai Jiao Tong university,Shanghai 200240,china.2 china.Information technology Security Evaluation Center,beijing 100085,china.3 Shanghai Key Laboratory of Scalable Computing and Systems,Shanghai Jiao Tong university,Shanghai,200240,china.4 State Key Laboratory of Information Security,graduate school of Chinese Academy of sciences,100039,china 1. Department of Computer science and Engineering Shanghai Jiao Tong University Shanghai 200240 China2. China Information Technology Security Evaluation Center Beijing 100085 China3. Shanghai Key Laboratory of Scalable Computing and Systems Shanghai Jiao Tong University Shanghai 200240 China4. State Key Laboratory of Information Security Graduate School of Chinese Academy of Sciences Beijing 100039 China

We present an accountable authority key policy attribute-based encryption (A-KPABE) *** this paper,we extend Goyal's work to key policy attribute-based encryption *** first generalize the notion of accountable authority in key policy attribute-based encryption scenario,and then give a *** addition,our scheme is shown to be secure in the standard model under the modified Bilinear Decisional Diffie-Hellman (mBDDH) assumption.

关键词： accountable authority key policy attribute-based encryption standard model access structure

CO observations of massive star forming regions at different evolutionary phases

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science china.Physics,Mechanics & Astronomy) 2006年第5期49卷 626-640页

作者： chen Xi1,2, XU Ye1,3, SHEN Zhiqiang1,3 & LI Jingjing1,2 1. Shanghai Astronomical Observatory, Chinese Academy of sciences, Shanghai 200030, china.2. graduate school of the Chinese Academy of sciences, beijing 100034, china.3. Joint Institute for Galaxy and Cosmology, Shanghai Astronomical Observatory and the university of science and technology of china, Shanghai 200030, china Shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai 200030 China graduate school of the Chinese Academy of sciences Beijing 100034 China Joint Institute for Galaxy Cosmology Shanghai Astronomical Observatory the university of science technology of china Shanghai 200030 China

The 12CO (J=1-0), 13CO (J=1-0) and C18O (J=1-0) emissions in 9 massive star forming regions, which are believed to be at different stages of massive star formation, were mapped with the 13.7 m millimeter wave telescope at Qinghai Station of Purple Mountain Observatory. Of the observed 9 sources, 13CO cores were detected in seven of them, and C18O cores in five of them. And only two sources associated with C18O cores and H2O masers showed the extended structures and strong outflows. This is the first detection of outflow associated with IRAS 22566+5828 in the observing field of S152/S153. The physical parameters of cores and outflows for these sources, derived from Local Thermal Equilibrium (LTE) analysis, are presented. These observing results suggest that the C18O cores will only appear when the gas density is high enough and the probability to have an outflow is very high when the clumps show the C18O and H2O maser simulta- neously.

关键词： star formation cloud core outflow H2O maser