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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,{2. Graduate School of the chinese academy of sciences, Beijing 100080,{2.) 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

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 2.04 (FVC2.04) and the Fingerprint Vendor Technology Evaluation 2.03 (FpVTE2.03), 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 fabrication parameters on the microstructure,in-plane anisotropy and magnetostriction of Fe-Ga thin films

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Rare Metals 2010年第6期29卷 583-588页

作者： WANG Bowen HUANG Wemnei CAO Shuying DU Yong HE Yuehui HUANG Baiyun Province-Ministry Joint Key Laboratory of Electromagnetic Field and Electrical Apparatus Reliability Hebei University of TechnologyTianjin 300130China international center for {2. physics Chinese Academy of SciencesShenyang 110015China State Key Laboratory of Powder Metallurgy Central South UniversityChangsha 410083China

The microstructure,in-plane anisotropy,and magnetic properties of Fe-Ga thin films were investigated by X-ray diffraction analysis,vibrating sample magnetometer,and capacitive cantilever *** in-plane induced anisotropy is well formed by the applied magnetic field during sputtering,and the anisotropy field Hk decreases with the sputtering power *** coercivity of Fe-Ga thin films decreases with increasing power when the sputtering power is less than 60 W and increases when the power is larger than 60 *** magnetostriction of the thin films reaches 66 × 10-6 at the sputtering power of 60 *** Fe-Ga films,which exhibit good field sensitivity,low coercivity and high magnetostriction,have been fabricated at the power of 60 W,and they can be used as the materials of magnetostrictive transducers.

关键词： metallic thin films magnetostriction magnetron sputtering anisotropy

Study on blister of the coating on solid cantilevers of hydraulic supports for coal mining

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Science china(Technological sciences) 2010年第12期53卷 3183-3188页

作者： MENG GuoZhe1, FU JinLiang2. SUN FeiLong1, SHAO YaWei1, ZHANG Tao1 & WANG FuHui1, 3 1 Corrosion and Protection Laboratory, Key Laboratory of Superlight materials and Surface Technology (Harbin Engineering University), Ministry of Education, Harbin 150001, china 2.Technology {2. of Zhengzhou Coal Mining Machinery Group Co. Ltd., Zhengzhou 100049, china 3 State Key Laboratory for Corrosion and Protection, Institute of Metal Research, chinese academy of sciences, shenyang 110016, china Corrosion and Protection Laboratory Key Laboratory of Superlight Materials and Surface Technology (Harbin Engineering University) Ministry of Education Harbin China Technology center of Zhengzhou Coal Mining Machinery Group Co. Ltd. Zhengzhou China State Key Laboratory for Corrosion and Protection Institute of Metal Research Chinese Academy of Sciences Shenyang China

In this work, blister of the Cu-Sn plus Cr coating on solid cantilevers of hydraulic supports for coal mining was investigated by hydrogen-charging, Devanathan-Stachurski method and electrochemical impedance spectroscopy (EIS) measurement. It was found that the permeation hydrogen during the pickling process and the electroplating process was responsible for the blisters. The residual tensile stress due to the machining process would increase the permeation hydrogen amount during pickling and electroplating processes.

关键词： hydrogen blister hydrogen permeation EIS sub-surface hydrogen concentration

Contribution of cloud condensate to surface rainfall process

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Progress in Natural Science:materials international 2006年第9期16卷 967-973页

作者： ZHOU Yushu , GUI Xiaopeng and LI Xiaofan ( Institute of Atmospheric physics, chinese academy of sciences, Beijing 10002.,{2. Joint center for Satellite Data Assimilation and NOAA/NESDIS/Office of Research and Applications Camp Springs, Maryland, USA) Institute of Atmospheric physics Chinese Academy of Sciences Beijing 100029 China Joint center for Satellite Data Assimilation NOAA NESDIS Office of Research and Applications Camp Springs MD United States

Contribution of cloud condensate to surface rainfall processes is investigated in a life span of tropical convection based on hourly data from a two-dimensional cloud resolving simulation. The model is forced by the large-scale vertical velocity, zonal wind and horizontal advections obtained from tropical ocean global atmosphere coupled ocean-atmosphere response experiment (TOGA COARE). The results show that during the genesis, development, and decay of tropical convection, calculations with water vapor overestimate surface rain rate, and cloud condensate plays an important role in correcting overestimation in surface rain rates. The analysis is carried out in deep convective clouds and anvil clouds during the development of tropical convection. The surface rain rates calculated with water vapor in deep convective clouds and anvil clouds have similar magnitudes, the large surface rain rate appears in deep convective clouds due to the consumption of water hydrometeors whereas the small surface rain rate occurs in anvil clouds because of the gain of ice hydrometeors. Further analysis of the grid data shows that the surface rain rates calculated with water vapor and with cloud condensate are negatively correlated with the correlation coefficient of - 0.85, and the surface rain rate calculated with cloud condensate is mainly contributed to the water hydrometeors in the tropical deep convective regime.

关键词： cloud condensate surface rain rate cloud resolving simulation.

First-principles study of the effects of Si doping on geometric and electronic structure of closed carbon nanotube

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Science Bulletin 2005年第17期 9-14页

作者： ZHOU Junzhe1 & WANG Chongyu1, 2.1. Department of physics, Tsinghua University, Beijing 100084, china 2. {2. Centre for materials physics, chinese academy of Sci-ences, shenyang 110016, china

The effects of Si doping on geometric and elec-tronic structure of closed carbon nanotube (CNT) are stud-ied by, a first-principles method, DMol. It is found that the local density of states at the Fermi level (EF) increases due to the Si-doping and the non-occupied states above the EF go down toward the lower energy range under an external elec-tronic field. In addition, due to the doping of Si, a sub-tip on the CNT cap is formed, which consisted of the Si atom and its neighbor C atoms. From these results it is concluded that Si-doping is beneficial to the CNT field emission properties.

关键词： carbon nanotube doping electronic structure field emission.

Transmission spectra characteristics of 1D photonic crystals with complex dielectric constant

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Rare Metals 2011年第2期30卷 150-154页

作者： GAO Yingjun CHEN Haibo QIU Hongguang LU Qianghua HUANG Changgao College of Physical Science and Engineering Guangxi University Nanning 5300041 China center oflnternational materials and {2. Chinese Academy of Science Shenyang 110016 China

The characteristics of photonic forbidden bands, transmission gain and absorption of one-dimensional （ID） dual-periodical photonic crystals （PC） with a complex dielectric layer were studied by using the optical transfer matrix （TM） method. The results show that the photonic band gap （PBG） of this structure is enlarged and many transmission resonance peaks appear in PBG. Large transmission gain for transmission peaks is obtained if the imaginary part of dielectric constant is negative. With the increase of the absolute value of the imaginary part, the transmission gain increases firstly and the transmittance gain gets to an apex. The imaginary parts of dielectric constant corresponding to transmission gain apex are different according to wavelength. However, the transmission ratio of resonance peaks is less than 1 if the imagi- nary part of dielectric constant is positive. The properties might be used to design multi-narrow-channel band filters and optical amplification devices synchronously.

关键词： photonic crystals one dimensional dielectric properties dielectric constant photonic band gap

Isotopic compositions of small shelly fossil Anabarites from Lower Cambrian in Yangtze Platform of South china: Implications for palaeocean temperature

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Progress in Natural Science:materials international 2007年第10期17卷 1185-1191页

作者： Chen Yongquan1,2. Jiang Shaoyong1, Ling Hongfei1, Yang Jinghong1 and Wan Defan3(1. State Key Laboatory for Mineral Deposits Research and center for Marine Geochemistry Research, Department of Earth sciences, Nanjing University, Nanjing 2.0093,{2. 2. Tarim Oilfield Company Exploration & Development Research Institute, Ku’erle 841000,{2. 3. Institute of Mineral Resources, chinese academy of Geological sciences, Beijing 100037,{2.) State Key Laboratory for Mineral Deposits Research Department of Earth Sciences Nanjing University Nanjing 210093 China Exploration and Development Research Institute Tarim Oilfield Company Ku'erle 841000 China Institute of Mineral Resources Chinese Academy of Geological Sciences Beijing 100037 China

Anabarites belong to small shelly fossils (SSF), which occur widely in the Lower Cambrian strata of Yangtze Platform in South china. They are phosphate shell in composition and represent the earliest stage of the Cambrian bioradiation of Bilateria, the so-called "Cambrian Explosion". In this study, we attempted to separate Anabarites fossils from Lower Cambrian dolostones, and we obtained samples of both the fossils (SSF) and the granular phosphates (GP). Isotopic analyses were performed on samples of SSF, GP, and matrix dolostone (DH-2.). The results showed that the δ30Si values of the quartz filling in fossils celoms, and the siliceous materials in granular phosphates are -0.6‰ and -0.7‰, which is different from normal sedimentary siliceous rocks from the Lower Cambrian strata (0—0.7‰) as reported by Li et al., but is consistent with the data for siliceous rocks and cherts of submarine hydrothermal origin. It is likely that a later hydrothermal replacement could have taken place in the SSF-bearing sedimentary rocks. The oxygen isotope values of the phosphate of SSF and GP are 16.8‰ and 17.0‰, respectively. These are significantly higher than the Neoproterozoic phosphate ores (10.9‰—13.9‰) as reported by Ling et al., hence, late diagenesis and hydrothermal replacement may not have caused a significant change in the oxygen isotope compositions of the small shelly fossils, and the calculated temperatures (2..4—2..3℃) for palaeo-seawater using a SSF phosphate oxygen isotope thermometer are therefore considered here as the upper limit of seawater temperature in the Early Cambrian ocean of the Yangtze Platform.

关键词： Anabarites oxygen isotope silicon isotope paleo-temperature.

Progress in multi-waveband observations of supernova remnants

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Progress in Natural Science:materials international 2008年第9期18卷 1057-1062页

作者： Xuejuan Yang a,b, Fangjun Lua, Wenwu Tian c,d,* a Particle Astrophysics center, Institute of High Energy physics, chinese academy of sciences, Beijing 100049, china b Department of Astronomy, Beijing Normal University, Beijing 100875, china c National Astronomical Observatories, chinese academy of sciences, 2.A Datun Road, Chaoyang District, CAS, Beijing 100012. china d Department of physics & Astronomy, University of Calgary, Alberta, Canada T2. 1N4 Particle Astrophysics center Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China Department of Astronomy Beijing Normal University Beijing 100875 China National Astronomical Observatories Chinese Academy of Sciences 20A Datun Road Chaoyang District CAS Beijing 100012 China Department of physics & Astronomy University of Calgary Alberta Canada T2N 1N4

The development of observational techniques has enriched our knowledge of supernova remnants. In this paper, we review the main progresses in the last decade, including new discoveries of supernova remnants and the associated (rare type of) pulsars, nucleosynthesis, the interaction between supernova remnants and molecular clouds, dust in the supernova remnants, shock physics, and cosmic ray accelerations.

关键词： Supernova remnant Observations

THE SYNERGISTIC INHIBITION STUDIES OF SEVERAL AMINES AND CHLORIDE ION ON IRON IN THE ACIDIC PERCHLORIDE SOLUTIONS

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Acta Metallurgica Sinica(English Letters) 1999年第5期12卷 952-957页

作者： J.H.Dong 1) ,J.Y.Chen 2.3) and. C.N.Cao 1) 1) State Key Laboratory for Corrosion and Protection of Metals, Institute of Corrosion and Protection of Metals, The chinese academy of sciences, shenyang 110015,{2. 2. The international center

The effect of chloride ion on the corrosion inhibition of iron caused by dencylamine(DA), dipentylamine(DDA) and dodecylamine(DPA) has been investigated by measuring the inhibitory coefficients for the anodic and cathodic processes at corrosion potential. It has been shown that the major synergistic inhibition effects between amines and chloride ions occur in the cathodic process, very weak in the anodic process. The anodic inhibition mechanism follows the competing adsorptive model, while the cathodic inhibition mechanism follows the cooperative adsorptive model.

关键词： synergistic inhibition organic amine chloride ion