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Studies and advances on joint source-channel encoding/decoding techniques in flow media communications

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Science China(Information sciences) 2010年第1期53卷 1-17页

作者： TU GuoFang1, LIU JianJun1, ZHANG Can1,2, GAO ShaoShuai3 & LI ShiDong4 1School of Information Science and Engineering, Graduate university of Chinese Academy of sciences, Beijing 100049, China 2state Key Laboratory of Information Security, Graduate university of Chinese Academy of sciences, Beijing 100049, China 3National Institute of Standards and Technology, Gaithersburg, MD 20899, usa, 4department of Mathematics, San Francisco state university, San Francisco, CA 94132, usa 1. School of Information Science and Engineering Graduate University of Chinese Academy of Sciences Beijing 100049 China2. State Key Laboratory of Information Security Graduate University of Chinese Academy of Sciences Beijing 100049 China3. National Institute of Standards and Technology Gaithersburg MD 20899 USA4. Department of Mathematics San Francisco State University San Francisco CA 94132 USA

Joint source-channel coding/decoding (JSCC/JSCD) techniques in flow media communications have become a state-of-the-art and one of the challenging research subjects in the spatial communication area. They have great application prospective and deep impact in various manned space flights, satellite missions, mobile radio communications and deep-space explorations. In the last few years, there have been influential achievements in JSCC/JSCD studies. This paper aims at an introduction to the basic principles of joint source-channel optimal design. A general summarization and classification for various existing JSCC/JSCD methods is addressed. Also presented is a JSCD scheme based on variable-length coding, capable of providing reliable resolutions for flow media data transmission in spatial communications.

关键词： joint source-channel coding/decoding rate allocation variable-length coding/decoding iterative decoding

Polyphyly of the fern family Tectariaceae sensu Ching:Insights from cpDNA sequence data

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Science China(Life sciences) 2007年第6期50卷 789-798页

作者： LIU HongMei1,2, ZHANG XianChun1, CHEN ZhiDuan1, DONG ShiYong3 & QIU YinLong4 1 state Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of sciences, Beijing 100093, China 2 Graduate university of Chinese Academy of sciences, Beijing 100039, China 3 South China Botanical Garden, Chinese Academy of sciences, Guangzhou 510650, China 4 department of Ecology and Evolutionary Biology, university of Michigan, Ann Arbor, MI 48109-1048, usa state Key Laboratory of Systematic Evolutionary Botany Institute of Botany Chinese Academy of Sciences Beijing 100093 China Graduate university of Chinese Academy of sciences Beijing 100039 China South China Botanical Garden Chinese Academy of Sciences Guangzhou 510650 China department of Ecology Evolutionary Biology University of Michigan Ann Arbor MI 48109-1048 USA

Tectariaceae are a pantropical fern family of about 20 genera, among which 8 are distributed in China. The morphological distinctiveness of the family is widely recognized, yet relatively little systematic research has been conducted on members of Tectariaceae. Phylogenetic analyses of chloroplast DNA sequence data (rbcL; atpB) from 15 species representing all 8 genera in China were carried out under parsimony criteria; Bayesian inference. The phylogenetic reconstructions indicated that the fern family Tectariaceae as traditionally circumscribed are polyphyletic. Ctenitis, Dryopsis, Lastreopsis clustered with; should be included within the newly-defined Dryopteridaceae,; Pleocnemia is also tentatively assigned to it. A narrowly monophyletic Tectariaceae is identified, which includes Ctenitopsis, Hemigramma, Pteridrys, Quercifilix,; Tectaria. In the single rbcL analysis, Arthropteris clustered with the above-mentioned monophyletic Tectariaceae. Although further investigations are still needed to identify infrafamilial relationships within the monophyletic Tectariaceae; to redefine several problematic genera, we propose a working concept here that better reflects the inferred evolutionary history of this group.

关键词： Tectariaceae, polyphyly, rbcL, atpB

The Symplectic Floer Homology of the Square Knot and Granny Knots

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Acta Mathematica Sinica,English Series 1999年第1期15卷 1-10页

作者： Weiping Lidepartment of Mathematics,Oklahoma state university,Stillwater,Oklahoma 74078-0613,usa department of Mathematics Oklahoma State University Stillwater USA

Using a kind of Mayer-Vietoris principle for the symplectic Floer homology of knots,we compute the symplectic Floer homology of the square knot and granny knots.

关键词： Knot Knot Cobordism Maslov Index Floer Homology

Cytoskeleton reorganization and FAK phosphorylation are involved in lanthanum(Ⅲ)-promoted proliferation and differentiation in rat osteoblasts

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Progress in Natural Science:Materials International 2009年第3期19卷 331-335页

作者： Xi Wang,Jian Huang*,Tianlan Zhang*,Kui Wang department of Chemical Biology,Peking university School of pharmaceutical sciences,38 Xueyuan Road,Beijing 100083,China [a]department of Chemical Biology Peking University School of Pharmaceutical Sciences 38 Xueyuan Road Beijing 100083 China

The effect of lanthanum ion(La 3+ )on osteoblast function and cytoskeleton is assessed in *** were isolated from Sprague- Dawley fetal neonatal *** proliferation and gene expression levels of cbfa-1,alkaline phosphatase(ALP),osteocalcin(OC),bone sialo- protein(BSP)and osteopontin(OPN)were examined by cell counting and *** F-actin was stained with rhodamine-con- jugated phalloidin and was visualized by a confocal *** the results,10à 8-10 à4M La 3+-induced osteoblast proliferation on day 2. Data from the RT-PCR assay revealed that 10à 6M La 3+up-regulated the expression levels of ALP,BSP,and cbfa-1 on day 4,while it enhanced the expressions of OC and OPN on day *** F-actin cytoskeleton was strengthened and reorganized under the exposure of La3 +.In addition, the phosphorylation of focal adhesion kinase(FAK)was significantly promoted in 24 h evaluated by Western blot *** findings indi- cate that La3 +promotes osteoblast activity through the phosphorylation of FAK and reorganization of the cytoskeleton.

关键词： La3 + Osteoblasts Proliferation Differentiation Cytoskeleton FAK phosphorylation

Focal plane wave-front sensing algorithm for high-contrast imaging

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Science China(Physics,Mechanics & Astronomy) 2009年第8期52卷 1284-1288页

作者： DOU JiangPei1,2,3,REN DeQing1,2,4,ZHU YongTian1,2 & ZHANG Xi1,2,3 1 National Astronomical Observatories/Nanjing Institute of Astronomical Optics & Technology,Chinese Academy of sciences,Nanjing 210042,China 2 Key Laboratory of Astronomical Optics & Technology,Nanjing Institute of Astronomical Optics & Technology,Chinese Academy of sciences,Nanjing 210042,China 3 Graduate university of Chinese Academy of sciences,Beijing 100049,China 4 Physics & Astronomy department,California state university northridge,18111 Nordhoff Street,northridge,California 91330-8268,usa National Astronomical Observatories/Nanjing Institute of Astronomical Optics & Technology Chinese Academy of Sciences Nanjing 210042 China Key Laboratory of Astronomical Optics & Technology Nanjing Institute of Astronomical Optics & Technology Chinese Academy of Sciences Nanjing 210042 China Graduate university of Chinese Academy of sciences Beijing 100049 China Physics & Astronomy department California State University Northridge 18111 Nordhoff Street Northridge California 91330-8268 USA

High-contrast imaging provided by a coronagraph is critical for the direction imaging of the Earth-like planet orbiting its bright parent star.A major limitation for such direct imaging is the speckle noise that is induced from the wave-front error of an optical *** derive an algorithm for the wave-front measurement directly from 3 focal plane *** 3 images are achieved through a deformable mirror to provide specific phases for the optics *** introduce an extra amplitude modulation on one deformable mirror configuration to create an uncorrelated wave-front,which is a critical procedure for wave-front *** simulation shows that the reconstructed wave-front is consistent with the original wave-front theoretically,which indicates that such an algorithm is a promising technique for the wave-front measurement for the high-contrast imaging.

关键词： high-contrast imaging multi-image algorithm speckle nulling technique wave-front sensing

SYNTHESIS OF POLYCATECHOL WITH ELECTROCHEMICAL ACTIVITY AND ITS PROPERTIES

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Chinese Journal of Polymer Science 2002年第6期20卷 517-524页

作者： Yong Kong Shao-lin Mu Bing-wei Mao department of Chemistry School of sciences, Yangzhou university Yangzhou 225002, China state Key Laboratory of Physical Chemistry of the Solid Surface, Xiamen university,Xiamen 361005, China Yangzhou Univ Sch Sci Dept Chem Yangzhou 225002 Peoples R China Xiamen Univ State Key Lab Phys Chem Solid Surface Xiamen 361005 Peoples R China

The electrochemical polymerization of catechol on platinum has been carried out using repeated potential cycling between -0.2 and 1.1 V (versus SCE). The electrolytic solution consisted of 0.2 mol dm(-3) catechol, 0.5 mol dm(-3) NaCl and 0.1 mol dm(-3) Na2HPO4 with pH 8.72. Catechol can not be polymerized at pH greater than or equal to 10.12. Polycatechol has an electrochemical lactivity at pH less than or equal to 4. The anodic and cathodic peak potentials of polycatechol shift towards more negative values as the pH of the solution increases from 1 to 4. The electrochemical activity of polycatechol hardly changes in this pH region, but it decreases slowly with time. This is caused by oxygen in air, which leads to an irreversible oxidation of polycatechol. This property is favorable for protecting metals from corrosion. Raman and FTIR spectra of polycatechol and catechol are quite different. AFM images of polycatechol films provide evidence that the image of the oxidized state of polycatechol is markedly different from that of the reduced one. This difference is caused by doping and dedoping of polycatechol.

关键词： catechol polycatechol electrochemical activity Raman spectra FTIR spectra AFM images

Structure analysis of ^(159)Sm and properties of odd-mass neutron-rich nuclei in mass-160 region

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Science China(Physics,Mechanics & Astronomy) 2011年第S1期54卷 81-87页

作者： YANG YingChun1 & SUN Yang1,2,3 1 department of Physics, Shanghai Jiao Tong university, Shanghai 200240, China 2Institute of Modern Physics, Chinese Academy of sciences, Lanzhou 730000, China 3department of Physics and Astronomy, university of Tennessee, Knoxville, Tennessee 37996, usa 1. department of Physics Shanghai Jiao Tong University Shanghai 200240 China2. Institute of Modern Physics Chinese Academy of Sciences Lanzhou 730000 China3. Department of Physics and Astronomy University of Tennessee Knoxville Tennessee 37996 USA

Recent fission experiment data provide interesting structure information for neutron-rich nuclei in the mass A ～ 160 region. We apply the projected shell model to study the strongly-deformed, neutron-rich Sm isotopes. We perform calculations for rotational bands up to spin I = 20 (29/2) for even-even (odd-neutron) Sm isotopes, and analyze the band structure of low-lying states with quasiparticle excitations. Emphasis is given to rotational bands based on one-quasiparticle (1-qp) configurations in the odd-mass 159Sm. The 159 Sm result is discussed together with those of the even-even isotopes 158,160Sm. New bands in 159Sm based on neutron 1-qp 1/2 and 5/2+ configurations are predicted. Electromagnetic transition probabilities are discussed.

关键词： projected shell model neutron-rich nuclei low-lying excitations isomeric states

Simultaneous detection of seven phenolic acids in Danshen injection using HPLC with ultraviolet detector

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Journal of Zhejiang university-Science B(Biomedicine & Biotechnology) 2008年第9期9卷 728-733页

作者： Jin-zhong XU, Jie SHEN, Yi-yu CHENG, Hai-bin QU (department of Chinese Medicine Science and Engineering, College of pharmaceutical sciences, Zhejiang university, Hangzhou 310058, China) department of Chinese Medicine Science and Engineering College of Pharmaceutical Sciences Zhejiang University Hangzhou 310058 China.

A high-performance liquid chromatographic (HPLC) method with ultraviolet (UV) detector had been developed for simultaneous quantification of danshensu, protocatechuic aldehyde, caffeic acid, salvianolic acid D, rosmarinic acid, salvianolic acid B and salvianolic acid A in Danshen injection. According to the UV spectra of these components, three detection wavelengths have been selected as follows: 280 nm for danshensu and protocatechuic aldehyde, 326 nm for caffeic acid, salvianolic acid D and rosmarinic acid, 286 nm for salvianolic acid B and salvianolic acid A. The limit of detection (LOD) was improved to be in the range of 0.008~0.160 μg/ml. Moreover, excellent linear behavior over the investigated concentration range was observed, with R>0.999 for all the analytes.

关键词： High-performance liquid chromatography (HPLC) Danshen injection (DSI) Phenolic acids Multi-wavelengths Quantification

Online uniform machine covering with the known largest size

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Progress in Natural Science:Materials International 2007年第11期17卷 1271-1278页

作者： Cao Shunjuan1,2 and Tan Zhiyi1,3(1. department of Mathematics, Zhejiang university, Hangzhou 310027, China 2. department of Mathematics, Zhejiang Forestry university, Hangzhou 311300, China 3. state Key Laboratory of CAD & CG, Zhejiang university, Hangzhou 310027, China) department of Mathematics Zhejiang University Hangzhou 310027 China department of Mathematics Zhejiang Forestry University Hangzhou 311300 China state Key Laboratory of CAD & CG Zhejiang University Hangzhou 310027 China

This paper investigates the semi-online scheduling problem with the known largest size on two uniform machines. The objective is to maximize the minimum machine completion time. Both lower bounds and algorithms are given. Algorithms are optimal for the majority values of s≥1, where s is the speed ratio of the two machines. The largest gap between the competitive ratio and the lower bound is about 0.064. Moreover, the overall competitive ratio 2 matches the overall lower bound.

关键词： scheduling and covering uniform machine design and analysis of algorithm online competitive ratio