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

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 {4.,Nanjing 21004.,{3. 2 Key Laboratory of Astronomical Optics & Technology,Nanjing Institute of Astronomical Optics & Technology,chinese academy of {4.,Nanjing 21004.,{3. 3.Graduate University of chinese academy of {4.,{14. 10004.,{3. 4.{13. & Astronomy Department,California State University Northridge,18111 Nordhoff Street,Northridge,California 913.0-8268,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

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Meteorological observations on Mount Everest in 2005

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Progress in Natural Science:Materials International 2007年第7期17卷 828-837页

作者： Xie Aihong~(1**) Qin Dahe~1 Ren Jiawen~1 Qin Xiang~1 Xiao Cunde~(1,2) Hou Shugui~1 Kang Shichang~(1,3. Yang Xingguo~(1,4. Jiang Youyan~1 (1.Key Laboratory of Cryosphere and Environment,Cold and Arid Regions Environment and Engineering Research Institute,chinese academy of sciences,Lanzhou 73.000,{3. 2.chinese academy of Meteorological Science,beijing 100081,{3. 3.Institute of Tibetan Plateau Research,chinese academy of sciences,beijing 100085,{3. 4.Gansu Provincial Meteorological Bureau,Lanzhou 73.000,{3.) [a]Key Laboratory of Cryosphere and Environment Cold and Arid Regions Environment and Engineering Research Institute Chinese Academy of Sciences Lanzhou China [b]chinese academy of Metoorological Science Beijing China [c]Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing China [d]Gansu Provincial Meteorological Bureau Lanzhou China

Mount Everest,the highest point on the Earth is often referred to as the earth's third pole as such the place is relatively inaccessible and little is known about its *** April 2005,an automatic weather station was installed at the mountain's North Col(6523.m a.s.l.).According to the observational 10-minute mean and daily records,the meteorological characteristics were analyzed. All the meteorological elements displayed obvious diurnal variations during May 1 to July 22,*** monthly variation of daily meteo- rological elements on Mount Everest coincided with that on Dingri,the closest routine meteorological station,with the high correlation co- efficients of 0.928,0.877,0.682,0.755,0.826 and 0.676(n=83.p3.0.4.5 and 0.4.7(n=83.p<0.001),*** other weather events on Mount Everest lagged one-day be- hind those on ***,forecasting of the weather events on Mount Everest from pressure on Dingri was more reliable than those from the other meteorological *** conclusions are much important for research on meteorology and climate changes in the region.

关键词： Mount Everest meteorological observation Dingri County radiation air temperature relative humidity air pressure wind

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X（3.72） and Bound State Problem of D0*0（0 D*0）

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原子核物理评论 2009年第S1期 16-21页

作者： LIU Yan-rui1,LIU Xiang2,3.DENG Wei-zhen2 (1 Institute of high energy physics,{3. academy of sciences,beijing 10004.,china 2 Department of physics,Peking University,beijing 100871,china 3.Centro de Física Terica,Departamento de Física,Universidade de Coimbra,P-3.04.516,Coimbra,Portugal)

We have performed a dynamical calculation of the bound state problem of D0D*0 by considering the pion and sigma meson exchange potential. Our preliminary analysis disfavors the molecular interpretation of X(3.72) if we use the experimental D*Dπ coupling constant g=0.59 and a reasonable cutoff around 1 GeV,which is the typical hadronic scale. In contrast,there probably exists a loosely bound S-wave BB* molecular state. Such a molecular state would be rather stable since its dominant decay mode is the radiative decay through B*→Bγ.

关键词： X(3.72) bound state molecule

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Threading dislocation density comparison between GaN grown on the patterned and conventional sapphire substrate by high resolution X-ray diffraction

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Science china(physics,Mechanics & Astronomy) 2010年第3期53卷 465-468页

作者： ZHANG YuChao1, XING ZhiGang2, MA ZiGuang2, CHEN Yao2, DING GuoJian2, XU PeiQiang2, DONG ChenMing3. CHEN Hong2 & LE XiaoYun1 1 School of physics and Nuclear energy Engineering, Beihang University, beijing 100190,{3. 2 Renewable energy Laboratory, Institute of physics, chinese academy of sciences, beijing 100190,{3. 3.School of Information and Communication, Tianjin Polytechnic University, Tianjin 3.0160,{3. 1. School of physics and Nuclear energy Engineering Beihang University Beijing 100190 China2. Renewable Energy Laboratory Institute of Physics Chinese Academy of Sciences Beijing 100190 China3. School of Information and Communication Tianjin Polytechnic University Tianjin 300160 China

GaN epifilms are grown on the patterned sapphire substrates (PSS) (0001) and the conventional sapphire substrates (CSS) (0001) by metal-organic chemical vapor deposition (MOCVD) using a novel two-step growth. high resolution X-ray diffraction (HR-XRD) is used to investigate the threading dislocation (TD) density of the GaN epifilms. The TD density is calculated from the ω-scans full width at half maximum (FWHM) results of HR-XRD. The edge dislocation destiny of GaN grown on the PSS is 2.7×108 cm-2, which is less than on the CSS. This is confirmed by the results of atomic force microscopy (AFM) measurement. The lower TD destiny indicates that the crystalline quality of the GaN epifilms grown on the PSS is improved compared to GaN epifilms grown on the CSS. The residual strains of GaN grown on the PSS and CSS are compared by Raman Scattering spectra. It is clearly seen that the residual strain in the GaN grown on PSS is lower than on the CSS.

关键词： GaN patterned sapphire substrate threading dislocation XRD

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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 {4., Shanghai 20003.,{3. 2. Graduate School of the chinese academy of {4., beijing 10003.,{3. 3. Joint Institute for Galaxy and Cosmology, Shanghai Astronomical Observatory and the University of Science and Technology of{3., Shanghai 20003.,{3. 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), 13.O (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, 13.O 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 {4. enough and the probability to have an outflow is very {4. when the clumps show the C18O and H2O maser simulta- neously.

关键词： star formation cloud core outflow H2O maser

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Interface delamination of the thermal barrier coating subjected to local heating

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Science china(Technological sciences) 2010年第12期53卷 3168-3174页

作者： WU ChenWu, HUANG ChenGuang & CHEN GuangNan Institute of Mechanics, chinese academy of sciences, {3. 100190,{4. 1. Institute of Mechanics Chinese Academy of Sciences Beijing 100190 China

To investigate the possible failure modes of the thermal barrier coating (TBC) used to protect the scramjet combustion chamber, the local heating via laser beam irradiation was utilized to simulate the service condition of high thermal flux and high temperature gradient. Firstly, the experimental method and process were described and the typical fracture morphology of the TBC under test were provided. Then, the theoretical and finite element modeling were carried out to study the temperature, deformation and stresses of the specimen when the top ceramic coat was subjected to local heating, and to demonstrate the mechanism on the failure of the TBC. It is revealed that the interface delamination shall appear and ultimately lead to the failure of the TBC under such thermal loading of local quick heating. According to the outcome of this study, the driving force of the interface delamination is influenced greatly by the key structural parameters and performance matching. Moreover, by utilizing the rules of the effects of these parameters on the fracture driving force, there is some possibility for the designer to optimize the performances of the TBC.

关键词： TBC local heating interface delamination FE modeling

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Relative position determination of a lunar rover using high-accuracy multi-frequency same-beam VLBI

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Science china(physics,Mechanics & Astronomy) 2010年第3期53卷 571-578页

作者： LIU QingHui1, CHEN Ming1, XIONG WeiMing2, QIAN ZhiHan1, LI JinLing1, HAO WangHong1,4. WANG GuangLi1, ZHENG WeiMin1, GUAN Di3. ZHU RenJie1, WANG WeiHua1, ZHANG XiuZhong1, JIANG DongRong1, SHU FengChun1, PING JinSong1 & HONG XiaoYu11 Shanghai Astronomical Observatory, chinese academy of sciences, Shanghai 20003.,{3. 2 Center for Space Science and Applied Research, chinese academy of sciences, beijing 100190,{3. 3.Lunar Explorer Engineering General Department, chinese academy of sciences, beijing 100012,{3. 4.beijing Institute of Tracking and Telecommunications Technology, beijing 100094.{3. 1. Shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai 200030 China2. Center for Space Science and Applied Research Chinese Academy of Sciences Beijing 100190 China4. Beijing Institute of Tracking and Telecommunications Technology Beijing 100094 China3. Lunar Explorer Engineering General Department Chinese Academy of Sciences Beijing 100012 China

Multi-frequency same-beam VLBI means that two explorers with a small separation angle are simultaneously observed with the main beam of receiving antennas. In the same-beam VLBI, the differential phase delay between two explorers and two receiving telescopes can be obtained with a small error of several picoseconds. The differential phase delay, as the observable of the same-beam VLBI, gives the separation angular information of the two explorers in the celestial sphere. The two-dimensional relative position on the plane-of-sky can thus be precisely determined with an error of less than 1 m for a distance of 3.8×105 km far away from the earth, by using the differential phase delay obtained with the four chinese VLBI stations. The relative position of a lunar rover on the lunar surface can be determined with an error of 10 m by using the differential phase delay data and the range data for the lander when the lunar topography near the rover and the lander can be determined with an error of 10 m.

关键词： same-beam VLBI differential phase delay relative position determination lunar rover

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VISCOELASTIC BEHAVIOR OF THE NON-HOOKE DEFORMATION BEFORE YIELDING IN UNIAXIAL DRAWING OF AMORPHOUS POLY(ETHYLENE TEREPHTHALATE)

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chinese Journal of Polymer Science 2001年第4期19卷 399-405页

作者： Zhen-hua Yuan De-yan Shen Ren-yuan Qian Polymer physics Laboratory Center for Molecular Science, Institute of Chemistry chinese academy of {3., {4. 100080 china chinese Acad Sci Inst Chem Ctr Mol Sci Polymer Phys Lab Beijing 100080 Peoples R China

Viscoelastic behavior of the non-Hooke deformation of amorphous PET film before yield was investigated in the temperature region 74.80.5 degreesC around the glass transition temperature. The film specimen was drawn to yield point followed by unloading to zero stress, then the residual deformation was held constant; while the subsequent evolution of the stress was recorded. An induction period was found in the course of stress evolution followed by a stress step-increase. The induction period decreases with increasing drawing temperature with an activation energy of 1.10 MJ/mol.K, which is attributed to the time needed for the relaxation of rubbery deformation through cooperative internal rotations. At temperatures lower than 74.degreesC, there is no stress increase or the induction period becomes too long to be observed. Thus the nature of anelasticity in the non-Hooke region before yielding is attributed to stress induced rubbery deformation. The experimental results are interpreted in terms of Perez' theological model of a series connected Hooks spring and a Voigt element consisting of a parallel connected elastic spring and a dashpot.

关键词： pre-yield deformation PET uniaxial drawing non-Hooke deformation viscoelasticity stress induced rubbery deformation

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Recommendation Method for Contrastive Enhancement of Neighborhood Information

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Computers, Materials & Continua 2024年第1期78卷 453-472页

作者： Hairong Wang beijing Zhou Lisi Zhang He Ma School of Computer Science and Engineering North Minzu UniversityNingxia750021China

Knowledge graph can assist in improving recommendation performance and is widely applied in various person-alized recommendation ***,existing knowledge-aware recommendation methods face challenges such as weak user-item interaction supervisory signals and noise in the knowledge *** tackle these issues,this paper proposes a neighbor information contrast-enhanced recommendation method by adding subtle noise to construct contrast views and employing contrastive learning to strengthen supervisory signals and reduce knowledge ***,first,this paper adopts heterogeneous propagation and knowledge-aware attention networks to obtain multi-order neighbor embedding of users and items,mining the high-order neighbor informa-tion of users and ***,in the neighbor information,this paper introduces weak noise following a uniform distribution to construct neighbor contrast views,effectively reducing the time overhead of view *** paper then performs contrastive learning between neighbor views to promote the uniformity of view information,adjusting the neighbor structure,and achieving the goal of reducing the knowledge noise in the knowledge ***,this paper introduces multi-task learning to mitigate the problem of weak supervisory *** validate the effectiveness of our method,experiments are conducted on theMovieLens-1M,MovieLens-20M,Book-Crossing,and Last-FM *** results showthat compared to the best baselines,our method shows significant improvements in AUC and F1.

关键词： Contrastive learning knowledge graph recommendation method

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Structural and microstructural transformations in Bi_2Sr_2Ca_(1-x)Y_xCu_2O_(8+y) system

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chinese Science Bulletin 1997年第3期42卷 192-196页

作者： SONG Chengyu, WEN Shulin and CHE Guangcan1. Shanghai Institute of Ceramics, chinese academy of sciences, Shanghai 200050,{3. 2. State Key Laboratory of Supercon-ductivity, Institute of {4., chinese academy of sciences, beijing 100080,{3. Shanghai Institute of Ceramics Chinese Academy of Sciences Shanghai 200050 China

SINCE the discovery of high-Tc superconductors, experiments have revealed that the phase diagrams of La2-xSrxCuO4.and YBa2Cu3.6+x resemble each other. The antiferromagnetic phase is commonly situated in the vicinity o... 详细信息

SINCE the discovery of high-Tc superconductors, experiments have revealed that the phase diagrams of La2-xSrxCuO4./sub> and YBa2Cu3./sub>O6+x resemble each other. The antiferromagnetic phase is commonly situated in the vicinity of the superconductive phase. In Bi-2212 sys-

关键词： Bi2Sr2Ca1-xYxCu2Oy substitution structural transformation.

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