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Progress in Natural Science:Materials International 2009年第11期19卷 1561-1568页

作者： Song Qin~(a,*),Yinchu Wang~(a,b) a Yantai Institute of Coastal Zone Research for Sustainable Development,chinese academy of sciences,Yantai 264003,china b graduate university of chinese academy of sciences,beijing 100049,china Yantai Institute of Coastal Zone Research for Sustainable Development Chinese Academy of Sciences Yantai 264003 China graduate university of chinese academy of sciences Beijing 100049 China

Prochlorococcus is a marine cyanobacterium of global *** ecotypes are adapted to either high-light(HL) or low-light (LL) *** ratio between chlorophyll(Chl) a and b is a distinguishing characteristic of these two ***,how this ratio evolved in Prochlorococcus during this ecotype differentiation remains *** analyses reveal that the ancestor of Prochlorococcus was typically low-light *** LL ecotype showed a stagnant evolution,and the HL ecotype was recently *** was an adaptive radiation after directional evolution in the Chl bla ratio *** in chlorophyllide a oxygenase(CAO) and positive selection on Clp protease contributed to the directional evolution of *** recombinant fragments of CAO were correlated with a large group of shared coevolving *** of positive selection was found in both subunits of *** bla ratio evolution,as annotated by molecular evidence,appears to be among the crucial reasons that explain how Prochlorococcus has become the dominant photosynthetic organism in the ocean.

关键词： Prochlorococcus Ch1 b/a ratio Adaptive evolution Trait evolution Ecotype differentiation

Convergence of the Vlasov-Poisson-Fokker-Planck system to the incompressible Euler equations

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Science china Mathematics 2006年第2期49卷 255-266页

作者： XIAO Ling, LI Fucai & WANG Shu academy of Mathematics and Systems Science, chinese academy of sciences, beijing 100080, china Department of Mathematics, Nanjing university, Nanjing 210093, china College of Applied sciences, beijing university of Technology, beijing 100022, china academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing China Department of Mathematics Nanjing University Nanjing China College of Applied sciences Beijing University of Technology Beijing China

We establish the convergence of the Vlasov-Poisson-Fokker-Planck system to the incompressible Euler equations in this paper. The convergence is rigorously proved on the time interval where the smooth solution to the incompressible Euler equations exists. The proof relies on the compactness argument and the so-called relative-entropy method.

关键词： Vlasov-Poisson-Fokker-Planck system incompressible Euler equations relative-entropy method.

Quasi-secure quantum dialogue using single photons

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Science china(Physics,Mechanics & Astronomy) 2007年第5期50卷 558-562页

作者： YANG YuGuang1,2 & WEN QiaoYan31 College of Computer Science and Technology, beijing university of Technology, beijing 100022, china 2 State Key Laboratory of Information Security, graduate university of the chinese academy of sciences, beijing 100049, china 3 School of Science, beijing university of Posts and Telecommunications, beijing 100876, china College of Computer Science and Technology Beijing University of Technology Beijing China State Key Laboratory of Information Security Graduate University of the Chinese Academy of Sciences Beijing China School of Science Beijing University of Posts and Telecommunications Beijing China

A quasi-secure quantum dialogue protocol using single photons was proposed. Different from the previous entanglement-based protocols, the present protocol uses batches of single photons which run back and forth between the two parties. A round run for each photon makes the two parties each obtain a classical bit of information. So the efficiency of information transmission can be increased. The present scheme is practical and well within the present-day technology.

关键词： quantum dialogue, single photon, quantum secure direct communication

Susceptibility Assessment of Landslides Caused by the Wenchuan Earthquake Using a Logistic Regression Model

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Journal of Mountain Science 2010年第3期7卷 234-245页

作者： SU Fenghuan Key Laboratory of Mountain Hazards and Land Surface Processes Chinese Academy of Sciences Chengdu China Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu China graduate university of the chinese academy of sciences Beijing China

The Wenchuan earthquake on May 12,2008 caused numerous collapses,landslides,barrier lakes,and debris *** susceptibility mapping is important for evaluation of environmental capacity and also as a guide for post-earthquake *** this paper,a logistic regression model was developed within the framework of GIS to map landslide *** County,a heavily affected area,was selected for the *** of landslides was prepared by interpretation of multi-temporal and multi-resolution remote sensing images(ADS40 aerial imagery,SPOT5 imagery and TM imagery,etc.) and field *** Certainly Factor method was used to find the influencial factors,indicating that lithologic groups,distance from major faults,slope angle,profile curvature,and altitude are the dominant factors influencing *** weight of each factor was determined using a binomial logistic regression *** susceptibility mapping was based on spatial overlay analysis and divided into five *** faults have the most significant impact,and landslides will occur most likely in areas near the *** of the area has a high or very high susceptibility,located in the northeast,south and southwest,including 65.3% of all landslides coincident with the *** susceptibility map can reveal the likelihood of future failures,and it will be useful for planners during the rebuilding process and for future zoning issues.

关键词： Landslide susceptibility WenchuanEarthquake GIS logistic regression certainty factor

PLS path model building:A multivariate approach to land price studies-A case study in beijing

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Progress in Natural Science:Materials International 2009年第11期19卷 1643-1649页

作者： Wenjie Wu~(a,b),Wenzhong Zhang~(a,*) a Institute of Geographic sciences and Natural Resources Research,CAS,beijing 100101,china b graduate university of chinese academy of sciences,beijing 100049,china Institute of Geographic sciences and Natural Resources Research CAS Beijing 100101 China graduate university of chinese academy of sciences Beijing 100049 China

Previous studies have revealed that statistical methods can be used to analyze land-leasing parcel ***,the conventional statistical methods used in land analysis have some limitations,especially in cases of limited observational *** this paper,with the help of geographic information system(GIS) techniques,a partial least squares(PLS) path model is applied to study the relationship between residential land prices and various determinants through a case study of beijing in *** a preliminary analysis,four latent variables are selected:accessibility of the workplace center,livability,traffic,and environment *** results show that the observation variables have a strong explanatory power for their corresponding latent variables,and the four latent variables have varying impacts on residential land *** the latent variables,accessibility to the workplace center has the strongest impact on the residential land price.

关键词： Land PLS path model GIS beijing

Joint source channel VL coding/decoding for deep space communication networks based on a space trellis

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Science china(Information sciences) 2011年第9期54卷 1883-1894页

作者： WU WeiRen 1,TU Juan 2,TU GuoFang 1,GAO ShaoShuai 1 & ZHANG Can 1,3 1 School of Information Science and Engineering,graduate university of chinese academy of sciences,beijing 100049,china 2 beijing Institute of Electronic System Engineering,china Aerospace Science & Industry Corp.,beijing 100854,china 3 State Key Laboratory of Information Security,graduate university of chinese academy of Science,beijing 100049,china School of Information Science and Engineering Graduate University of Chinese Academy of Sciences Beijing China beijing Institute of Electronic System Engineering China Aerospace Science & Industry Corp. Beijing China State Key Laboratory of Information Security Graduate University of Chinese Academy of Science Beijing China

This paper presents joint source channel variable length (VL) coding/decoding based on a space *** constructing a joint decoding plane trellis,better decoding performance can be achieved than by using the bit-level decoding ***,the plane trellis is complicated,which results in high decoding complexity for decoding VL turbo *** solve this problem,we construct a space trellis and design a low-complexity joint decoding algorithm with a variable length symbol-a posteriori probability (VLS-APP) algorithm in resource constrained deep space communication *** results show that the proposed approach reduces the decoding complexity by 10% compared with the plane trellis,and the gain of Eb/N0 is about 0.2 dB at SER=***,it provides substantial error protection for variable-length encoded image data.

关键词： joint coding/decoding VL turbo codes space trellis VLS-APP

Preparation and Characterization of Co_(0.3)Cr_(0.7)O_x Particles Using for Thermal Radiation Coating

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稀有金属材料与工程 2012年第S1期41卷 100-103页

作者： Luo Lijie1,2,Huang Chuanbing1,Zhu Yongping1,Zhang Weigang1 1 State Key Laboratory of Multi-phase Complex Systems,Institute of Process Engineering,chinese academy of sciences,beijing 100190,china 2 graduate university of chinese academy of sciences,beijing 100049,china chinese Acad Sci Inst Proc Engn State Key Lab Multiphase Complex Syst Beijing 100190 Peoples R China chinese Acad Sci Grad Univ Beijing 100049 Peoples R China

Novel Co0.3Cr0.7Ox(x=2-3)particles with spinel structure were synthesized via precipitation method through the reactions among CoSO4,Cr(NO3)3 and NaOH solutions,followed by spray-drying and sintering at 1200 ℃for 4h in the *** particles were characterized by X-ray diffraction(XRD)and scanning electron microscopy(SEM).The XRD results revealed that the particles are composed of Co0.3Cr0.7Ox phase without the presence of other *** SEM observation showed that the particles are in the shape of sphere with well *** radiation test indicated that the total infrared normal emissivity of the coating made of Co0.3Cr0.7Ox can be up to 0.92 at 800℃.And the normal emissivities of the prepared Co0.3Cr0.7Ox particles are always slightly larger than those of CoCr2O4 particles prepared by solid-state reaction method in the test temperature range of 50-300℃.The relatively high thermal emissivity of Co0.3Cr0.7Ox is assumed to be mainly attributed to the spinel *** results indicated that Co0.3Cr0.7Ox particles are a good thermal radiation material,which can be used as infrared radiation layer in thermal protection system.

关键词： Co0.3Cr0.7Ox particles preparation precipitation thermal radiation coating

Non-Gaussianity of Racetrack Inflation Models

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Communications in Theoretical Physics 2007年第7期48卷 189-192页

作者： SUN Cheng-Yit ZHANG De-Hai Department of Physics,The graduate School of The chinese academy of sciences,beijing 100049,china Department of Physics The Graduate School of The Chinese Academy of Sciences Beijing 100049 China

In this paper,we use the result in[*** and ***,arXiv:astro-ph/0510709]to calculate thenon-Gaussianity of the racetrack models in[***-Pillado,et al.,JHEP 0411(2004)063;arXiv:hep-th/0406230]and[***-Pillado,et al.,arXiv:hep-th/0603129].The two models give different *** of themare ***,we find that,for multi-field inflationary models with the non-trivial metric of the field space,the condition of the slow-roll cannot guarantee small non-Gaussianities.

关键词： non-Gaussianity non-linear parameter racetrack inflation

Transgenic expression of DwMYB2 impairs iron transport from root to shoot in Arabidopsis thaliana

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Cell Research 2006年第10期16卷 830-840页

作者： Yan-Hong Chen~(1,2,3) Xue-Min Wu~5 Hong-Qing Ling~4 Wei-Cai Yang~1 ~1The Key Laboratory of Molecular and Developmental Biology,Institute of Genetics and Developmental Biology,chinese academy of sciences,beijing 100101 china ~2graduate university of the chinese academy of sciences,19 Yuquan Road,beijing 100049,china ~3School of Life Science,Nantong university,Nantong 226007 china ~4The State Key Laboratory of Plant Cell and Chromosome Engineering,Institute of Genetics and Developmental Biology,chinese academy of sciences,beijing 100101,china The Key Laboratory of Molecular and Developmental Biology Institute of Genetics and Developmental Biology Chinese Academy of Sciences Beijing China graduate university of the chinese academy of sciences Beijing China School of Life Science Nantong University Nantong China Department of Botany University of British Columbia 6270 University Blvd. Vancouver Canada The State Key Laboratory of Plant Cell and Chromosome Engineering Institute of Genetics and Developmental Biology Chinese Academy of Sciences Beijing China

In plant,iron uptake and homeostasis are tightly regulated to ensure its absorption from soil and to avoid excessiron in the *** genes involved in this process have been identified during past several years,but there are manyproblems remain unsolved in the genetic regulation of whole plant iron trafficking and *** transcriptionfactors contain tandem repeats of a～50 amino acid DNA-binding motif (R) and are involved in the regulation of manyaspects of plant development,hormone signaling and ***,we report that the ectopic expression of orchidR2R3-MYB gene DwMYB2 in Arabidopsis thaliana confers the transgenic plants hypersensitivity to iron *** DwMYB2 transgenic plants,the iron content in root is two-fold higher compared to that in wild-type root,while thereverse is true in *** imbalance of iron content in root and shoot suggested that the translocation of iron fromroot to shoot was affected by the expression of DwMYB2 in the transgenic ***,gene chip and reversetranscription-polymerase chain reaction analysis revealed that the ferric-chelate reductase gene,AtFRO2,and the irontransporter gene,AtIRT1 and AtIRT2,are up-regulated by DwMYB2 expression,while other potential iron transporterssuch as AtIREG1,AtFRD3 and NRAMP1 are *** addition,the expression of several putative peptidetransporters and transcription factors are also altered in the 35S::DwMYB2 transgenic *** data provide us insightinto the whole plant translocation of iron and identify candidate genes for iron homeostasis in plants despite the fact thata heterologous gene was expressed.

关键词： DwMYB2 iron uptake and homeostasis iron transporters Arabidopsis

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) 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 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.