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Improving the accuracy of image-based forest fire recognition and spatial positioning

Science china(Technological sciences) 2010年第S1期53卷 184-190页

作者： JIANG LiLi 1,QI QingWen 1,ZHANG An 1,GUO ChaoHui 2 & CHENG Xi 1,3.1 Institute of Geographical sciences and Natural Resources Research,chinese academy of sciences,beijing 100101,china 2 china Center for Resources Satellite Data and Applications,beijing 100094,china 3.9} university of chinese academy of sciences,beijing 100049,china Institute of Geographical sciences and Natural Resources Research Chinese Academy of Sciences Beijing China china Center for Resources Satellite Data and Applications Beijing China graduate university of chinese {3. of sciences Beijing China

Forest fires are frequent natural *** is necessary to explore advanced means to monitor,recognize and locate forest fires so as to establish a scientific system for the early detection,real-time positioning and quick fighting of forest *** paper mainly expounds methods and algorithms for improving accuracy and removing uncertainty in image-based forest fire recognition and spatial ***,we discuss a method of forest fire recognition in visible-light *** are four aspects to improve accuracy and remove uncertainty in fire recognition:(1)eliminating factors of interference such as road and sky with high brightness,red leaves,other colored objects and objects that are lit up at night,(2)excluding imaging for specific periods and azimuth angles for which interference phenomena repeatedly occur,(3.improving the thresholding method for determining the flame border in image processing by adjusting the threshold to the season,weather and region,and (4)integrating the visible-light image method with infrared image ***,we examine infrared-image-based methods and approaches of improving the accuracy of forest fire recognition by combining the spectrum threshold with an object feature value such as the normalized difference vegetation index and excluding factors of disturbance such as interference signals,extreme weather and high-temperature ***,a method of visible analysis to enhance the accuracy of forest fire positioning is examined and realized;the method includes decreasing the visual angle,selecting central points,selecting the largest spots,and judging the selection of fire spots according to the central *** studies are examined and the results are found to be satisfactory.

关键词： forest fire monitoring spatial positioning accuracy improvement

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A revision of Clematis ***(Ranunculaceae)

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Journal of Systematics and Evolution 2009年第6期47卷 552-580页

作者： ~(1,2)Wen-Jing YANG ~1Liang-Qian LI~* ~3.ei XIE 1(State Key Laboratory of Systematic and Evolutionary Botany,Institute of Botany,chinese academy of sciences,{3. 100093.china) 2(graduate university of chinese academy of sciences,{3. 100049,china) 3.Southwestern{13. Germplasm Bank of Wild Species,Kunming Institute of Botany chinese academy of sciences Kunming 650204,china) (State Key Laboratory of Systematic and Evolutionary Botany Institute of Botany Chinese Academy of Sciences Beijing 100093 China) (graduate university of chinese {3. of sciences Beijing 100049 China) (Southwestern china Germplasm Bank of Wild Species Kunming Institute of Botany Chinese Academy of Sciences Kunming 650204 China)

Clematis *** is revised in this paper based on the examination of a large number of herbarium specimens,extensive field observations,and morphometric *** taxonomic history and geographical distribution of the section are given,the relationships among the species are discussed,and the evolutionary trends of some characters in the section are *** staminodes of the plants in this section may have evolved from the outer stamens with petaloid filaments and gradually disappearing ***,they may have evolved in two different *** possibility is that the staminodes elongate and become lanceolate,as long as sepals,and their apices turn into *** other is that the staminodes are spathulate,but not elongating,as long as stamens,and their apices turn into retuse from obtuse and *** evolutionary trend of sepals may be from thin to thick in texture,and the veins from non-prominent to *** a result,five new series are established and nine species, two subspecies and nine varieties(including three new ranks) are recognized in this *** identification key is provided,and each taxon is described and *** sibirica and Clematis ochotensis are treated as subspecies of Clematis alpina due to their subtle differences and lack of,or few,overlapping *** fusijamana and Clematisfauriei are recognized as varieties of *** *** for the continuous variation of the velutinous strips on the sepal *** iliensis is treated as variety of *** *** for the continuous variation of leaf division *** variations in sepal color and basal caruncle size support degrading Clematis chiisanensis as a variety of Clematis *** North American *** may be primitive,whereas *** may be the most advanced taxon in this *** and *** are closely related to each ***,the systematic position of se

关键词： Clematis sect.Atragene Ranunculaceae taxonomic revision

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Effects of the grain size distribution on the temperature-dependent magnetic susceptibility of magnetite nanoparticles

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Science china Earth sciences 2010年第7期53卷 1071-1078页

作者： ZHAO XiangYu1,2 & LIU QingSong1 1 Paleomagnetism and Geochronology Laboratory (SKL-LE), Institute of Geology and Geophysics, chinese academy of sciences, {3. 100029, china 2 graduate university of chinese academy of sciences, beijing 100049, china Paleomagnetism and Geochronology Laboratory (SKL-LE) Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China graduate university of chinese {3. of sciences Beijing China

Magnetite is an important magnetic remanence carrier in natural samples and therefore is of great interest in paleo-, rock-, and environmental magnetism. The magnetic properties of magnetite depend on many factors, e.g., concentration and grain size distribution (GSD). In this study, we theoretically investigated the temperature-dependent susceptibility (TDS) of magnetite nanoparticles with a lognormal GSD. Results show that the TDS is affected highly by the GSD mainly in three aspects. Firstly, the unblocking process becomes smoother with the increase of distribution width, characterizing as a wider Hopkinson peak on the TDS curve. Secondly, the blocking temperature increases with the increase of the median diameter or/and the distribution width. Thirdly, the maximum susceptibility decreases with the increase of distribution width, and has a logarithmic function relation with the standard deviation of the distribution. As a case study, this model was further applied to the thermal products of the chinese loess/paleosol samples to determine the granulometry of newly-formed magnetite upon heating based on TDS curves. The results demonstrate the fidelity and feasibility of this method to determine the GSD of nano-sized magnetic particles.

关键词： Néel theory temperature dependence of susceptibility grain size distribution

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CH_4 uptake flux of Leymus chinensis steppe during rapid growth season in Inner Mongolia,china

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Science china Earth sciences 2010年第7期53卷 977-983页

作者： GENG YuanBo1, LUO GuangQiang1,2 & YUAN GuoFu1 1 Institute of Geographic sciences and Natural Resources Research, chinese academy of sciences, beijing 100101, china 2 graduate university of chinese academy of sciences, beijing 100049, china Institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences Beijing China graduate university of chinese {3. of sciences Beijing China

The influence of near ground atmosphere CH4 concentration, soil water content, soil Eh, plants, soil temperature, and pH on CH4 uptake flux of Leymus chinensis steppe during rapid growth season was studied using field in-situ measurement in Xilin River basin of Inner Mongolia, china. The results showed that CH4 uptake flux was positively correlated with near ground atmosphere CH4 concentration and soil Eh but negatively correlated with soil water content. Precipitation may decrease the CH4 flux by increasing the soil water content. The average fluxes of three treatments during the observation period were 1.52 (natural conditions, 1.51 (aboveground plants were excluded), and 2.00 mg m?2 d?1 (all plants were removed), respectively. The difference between the CH4 flux of natural condition treatment and that of removing aboveground plants treatment is small, whereas the flux of removing all plants treatment is larger than the other two treatments. This means that the contribution of aboveground plants to CH4 uptake flux is smaller than that of roots or roots-removing process. CH4 uptake flux is not sensitive to soil temperature and the narrow-ranged soil pH (6.3.–7.86). The Leymus chinensis steppe acts as a sink for CH4, and thus more studies should be focused on its affecting factors and related mechanisms.

关键词： CH4 uptake flux Leymus chinensis steppe affecting factors static opaque chamber/gas chromatography method

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Effects of combined substitution of Dy and Mo or Si on the crystal structures and magnetic properties of Nd_(1-y)Dy_yFe_(11-x)TiM_x(M=Mo,Si) compounds

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Science china Chemistry 2009年第8期52卷 1097-1103页

作者： LI XiangJun,ZHENG Na,HU ZhongBo & YUAN ZhuoBin College of Chemistry and Chemical Engineering,graduate university of chinese {3. of sciences,beijing 100049,china College of Chemistry and Chemical Engineering Graduate University of Chinese Academy of Sciences Beijing China

A series of Nd1-yDyyFe11-xTiMx(M=Mo,Si) alloys have been prepared by arc melting and studied by X-ray diffraction and neutron *** samples are found to crystallize in the ThMn12-type *** lattice parameters a and c and unit cell volume V of Nd0.5Dy0.5Fe11-xTiMox alloys increase linearly with increasing content of Mo(x),while the lattice parameters a and c and unit cell volume V of Nd0.5Dy0.5Fe11-xTiSix alloys decrease linearly with increasing content of Si(x).In NdyDy1-yFe11-xTiMx(M=Mo,Si) compounds,Ti and Mo atoms preferentially occupy the 8i sites and Si atoms preferentially occupy the 8j and 8f *** measurements show that the substitution of Fe by either Mo or Si leads to a decrease in the Curie temperature.

关键词： rare earth-transition metal compounds crystal structure X-ray diffraction neutron diffraction

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Overview of HBV whole genome data in public repositories and the chinese HBV reference sequences

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Progress in Natural Science:Materials International 2008年第1期18卷 13-20页

作者： Guanghua Wu a,b, Huiguo Ding c, Changqing Zeng b,* a graduate School of chinese academy of {3., beijing 100049, china b beijing Institute of Genomics, chinese academy of {3., beijing 1013.0, china c beijing Youan Hospital, Capital Medical {13., beijing 100069, china graduate School of chinese academy of {3. Beijing 100049 China beijing Institute of Genomics Chinese Academy of Sciences Beijing 101300 China beijing Youan Hospital Capital Medical University Beijing 100069 China

The number of Hepatitis B virus (HBV) whole genomic sequences in public nucleotide databases (GenBank, EMBL, and DDBJ) had reached 866 by January 1, 2007. Coming from 46 countries and regions, these sequences were categorized as eight genotypes (A–H). With the statistical and phylogenetic analysis on all available complete genomic data of HBV, we here present an overview of HBV sequences in public databases. From all registered 229 HBV genomes in chinese regions as well as 59 sequencing data from our research group, we report the establishment of reference sequences of HBV strains prevailing in china. These analyses provide clues for the effects of HBV genotypes in host clinical progressions, geographic distribution of the infection, and the viral evolutionary history. Moreover, the viral sequence reference would be helpful in the identiffcation of various HBV mutations. Based on the analysis of various public databases, we suggest that the chinese HBV database with the clinical information should be constructed.

关键词： Public databases HBV genomic sequences Genotype Subtype chinese reference sequences

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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 {3.,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/040623.]and[***-Pillado,et al.,arXiv:hep-th/0603.29].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

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Molecular mechanism of dehydrin in response to environmental stress in plant

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Progress in Natural Science:Materials International 2007年第3期17卷 237-246页

作者： ZHANG Yuxiu , WANG Zi and XU Jin (Department of Bioengineering, School of Chemical and Environmental Engineering, china university of Mining and Technology (beijing), beijing 100083. china Department of Biology, graduate university of chinese academy of sciences, beijing 100049, china) Department of Bioengineering School of Chemical and Environmental Engineering China University of Mining and Technology (Beijing) Beijing 100083 China Department of Biology Graduate University Chinese Academy of Sciences Beijing 100049 China

Dehydrins, known as the D-11 subgroup of late embryogenesis abundant (LEA) protein, are an immunologically distinct family of proteins, which typically accumulate in desiccation-tolerant seed embryo or in vegetative tissues in response to various environmental stresses such as drought, salinity and freezing. The existence of conservative sequences designated as K, S, and Y segments is a structural feature of dehydrins, and the K segment found in all dehydrins represents a highly conserved 15 amino acid motif (EKKGIMDKIKEKLPG) and forms an amphiphilicα-helix. According to the arrangement of these domains and clustering analysis, dehydrins are subdivided into 5 subtypes: YnSK, Kn, KnS, SKn and YnK. Different types of dehydrins are induced by different environmental stress in plants. Study results showed that dehydrins might play important protective roles under abiotic stress via a number of different mechanisms, including improving or protecting enzyme activities by the cryoprotective activity in responding to freeze/thaw or dehydration; stabilizing vesicles or other endomembrane structures by function as the membrane stabilizer during freeze induced dehydration, and preventing the membrane system from the oxidative damage induced by reactive oxygen radicals as the radical scavenger. Here, the gene expression and molecular mechanisms of dehydrin in response to stress in plants are discussed.

关键词： dehydrin stress mechanism.

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Review on the study of entanglement in quantum computation speedup

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chinese Science Bulletin 2007年第16期52卷 2161-2166页

作者： DING ShengChao1,3.& JIN Zhi1,2,1 Institute of Computing Technology,chinese academy of sciences,{3. 100080,china 2 academy of Mathematics and Systems Science,chinese academy of sciences,{3. 100080,china 3.graduate university of chinese academy of sciences,{3. 100080,china Institute of Computing Technology Chinese Academy of Sciences Beijing China graduate university of chinese {3. of sciences Beijing China academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing China

The role the quantum entanglement plays in quantum computation speedup has been widely disputed. Some believe that quantum computation's speedup over classical computation is impossible if entan-glement is absent,while others claim that the presence of entanglement is not a necessary condition for some quantum algorithms. This paper discusses this problem systematically. Simulating quantum computation with classical resources is analyzed and entanglement in known algorithms is reviewed. It is concluded that the presence of entanglement is a necessary but not sufficient condition in the pure state or pseudo-pure state quantum computation speedup. The case with the mixed state remains open. Further work on quantum computation will benefit from the presented results.

关键词：量子论量子纠缠量子计算加速模拟

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An Efficient High-Resolution Shock-Capturing Scheme for Multi-Dimensional Flows I. Hydrodynamics

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chinese Journal of Astronomy and Astrophysics 2006年第6期6卷 680-688页

作者： Cong Yu National Astronomical Observatories / Yunnan Astronomical Observatory, chinese academy of sciences, Kunming 650011 {3. School of chinese academy of sciences, beijing 100049 National Astronomical Observatories / Yunnan Astronomical Observatory Chinese Academy of Sciences Kunming 650011 graduate School of chinese academy of {3. Beijing 100049

Many problems at the forefront of theoretical astrophysics require a treatment of dynamical fluid behavior. We present an efficient high-resolution shock-capturing hydrodynamic scheme designed to study such phenomena. We have implemented a weighted, essentially non-oscillatory （WENO） scheme to fifth order accuracy in space, lILLE approximate Riemann solver is used for the flux computation at cell interface, which does not require spectral decomposition into characteristic waves and so is computationally friendly. For time integration we apply a third order total variation diminishing （TVD） Runge-Kutta scheme. Extensive testing and comparison with schemes that *** characteristic decomposition are carried out demonstrating the ability of our scheme to address challenging open questions in astrophysics.

关键词： accretion - hydrodynamics- method numerical - shock waves

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