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Optimized Chebyshev Fourier migration:A wide-angle dual-domain method for media with strong velocity contrasts

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Optimized Chebyshev Fourier migration:A wide-angle dual-doma...

中国科学院地质与地球物理研究所第十届(2.10年度)学术年会

作者： Jin-Hai Zhang,Wei-Min Wang,Shu-Qin Wang,and Zhen-Xing Yao 1 chinese academy of {2.,Institute of Geology and Geophysics,{3.,china. 2.chinese academy of {2.,Institute of Tibetan Plateau Research,Key Laboratory of Continental Collision and Plateau Uplift,{3.,china. 3.Minzu University of china,Institute of Information Engineering,{3.,china.

A wide-angle propagator is essential when imaging complex media with strong lateral velocity contrasts in one-way wave-equation *** have developed a dual-domain one-way propagator using truncated Chebyshev polynomials and a globally optimized *** method increases the accuracy of the expanded square-root operator by adding two high-order terms to the traditional split-step Fourier ***,we approximate the square-root operator using Taylor expansion around the reference background ***,we apply the first-kind Chebyshev polynomials to economize the results of the Taylor ***,we optimize the constant coefficients using the globally optimized scheme,which are fixed and feasible for arbitrary velocity *** analysis and numerical experiments have demonstrated that the method has very high accuracy and exceeds the unoptimized Fourier finite-difference propagator for the entire range of practical velocity contrasts. The accurate propagation angle of the method is always about 60°under the relative error of 1%for complex media with weak,moderate,and even strong lateral velocity *** method allows us to handle wide-angle propagations and strong lateral velocity contrast simultaneously by using Fourier transform *** four 2. Fourier transforms are required for each step of 3. wavefield extrapolation,and the computing cost is similar to that of the Fourier finite-difference *** with the finite-difference method,our method has no two-way splitting error(i.e.,azimuthal-anisotropy error)for 3. cases and almost no numerical dispersion for coarse *** addition, it has strong potential to be accelerated when an enhanced fast Fourier transform algorithm emerges.

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聚硅氧烷包夹聚合硅基高效液相色谱固定相的表征及其色谱性能

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分析测试学报 2001年第5期20卷 34-37页

作者：杨瑞琴蒋生祥陈立仁中国人民公安大学侦查系北京100038 中国科学院兰州化学物理研究所分析测试中心甘肃兰州730000

利用元素分析、红外光谱、扫描电镜及汞压吸附法对制备的聚硅氧烷包夹硅基反相高效液相色谱固定相进行了表征 ,给出了该固定相的结构信息及其与色谱性能的关系 ;用滴定法测定了该固定相表面硅羟基数目 ;考察了该固定相对碱性化合物的分... 详细信息

利用元素分析、红外光谱、扫描电镜及汞压吸附法对制备的聚硅氧烷包夹硅基反相高效液相色谱固定相进行了表征 ,给出了该固定相的结构信息及其与色谱性能的关系 ;用滴定法测定了该固定相表面硅羟基数目 ;考察了该固定相对碱性化合物的分离性能 ;由表征和色谱性能考察结果可知 ,该固定相表面的羟基基本被覆盖 ,因此 ,可在碱性流动相中长期使用。

关键词：高效液相色谱固定相表征硅胶聚硅氧烷碱性化合物分离色谱性能

Timing in the Time Domain: Cygnus X-1

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chinese Journal of Astronomy and Astrophysics 2001年第4期1卷 313-332页

作者： Ti-Pei Li (Department of Physics and Center for Astrophysics, Tsinghua University, beijing 100084 High Energy Astrophysics Lab., Institute of High Energy Physics, chinese {2. of {3., beijing 10003.)E-mail:litp@*** Department of Physics and Center for Astrophysics Tsinghua University Beijing 100084 High Energy Astrophysics Lab. Institute of High Energy Physics Chinese Academy of Sciences Beijing 100039

Quantities characterizing temporal property, e.g., power density, coherence, and time lag, can be defined and calculated directly in the time domain without using the Fourier transformation. Spectral hardness, variability duration, and correlation between different characteristic quamtities on different time scale can be studied in the time domain as well. The temporal analysis technique in the time domain is a powerful tool, particularly in studying rapid variability on short time scales (or in high frequencies). Results of studying variabilities of X-rays from Cyg X-1 with the analysis technique in the time domain and RXTE data reveal valuable clues to understanding production and propagation processes of X-rays and structure of accretion disk in the black hole system.

关键词： methods: data analysis - stars: individual (Cygnus X-1) - X-rays: stars

Slope Reinforcement for Housing in Three Gorges Reservoir Area

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Slope Reinforcement for Housing in Three Gorges Reservoir Ar...

中国科学院地质与地球物理研究所第11届（2.11年度）学术年会

作者： WU Faquan~1,LUO Yuanhua~2.CHANG Zhonghua~(1*) 1 Institute of Geology and Geophysics,chinese academy of {2.,beijing 10002.,china 2.Office of Three Gorges Project Construction Committee,the State Council of china,beijing 10003.,china

The Three Gorges Project of the Yangtze River is the largest hydropower-complex project under construction in the *** the large-scale relocation projects,2.74 engineered slopes are formed along with the construction of new *** this paper,the cutting slopes are mainly soil slopes and rock *** slopes include residual soil slopes,colluvial accumulation slopes,swelling soil slopes,and artificial earth fill slopes,*** slopes include blocky structure rock slopes,layer structure rock slopes,and clastic structure rock slopes,etc. Varied protection measures have been used for slope protection in the reservoir area including shotcrete concrete-anchor bars,frame beams,retaining walls, slope stabilizing piles,sheet-pile walls,anchorage anti-shear tunnels,flexible protection grids,and drainage,***,slope deformation monitoring systems have been set up to monitor deformation failure and the stability state of *** protection measures have guaranteed slope safety and maintained a harmony with the urban environment and surrounding landscape.

关键词： Slope reinforcement Housing for resettlement Three Gorges Reservoir

Nanoscale Molecular Electronic Devices and Self-assembly Growth

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Nanoscale Molecular Electronic Devices and Self-assembly Gro...

TFC’03.国薄膜技术学术研讨会

作者： Hong jun Gao Institute of Physics, chinese academy of {2., {3. 100080, china

Nanoscale molecular devices and the characterization with scanning probetechniques have aroused much attention in last *** particular interest is theuse of organic polymers having novel functional properties within a single molecule ormolecular complex to fabricate electronic devices at the molecular *** thispresentation,we will first present the formation of self-assembled unique“seahorse”

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How is neuronal homeostasis maintained?

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How is neuronal homeostasis maintained?

第十一次中国生物物理学术大会暨第九届全国会员代表大会

作者： Jin-Hui Wang Institute of Biophysics,chinese academy of {2.,{3. china 100101

＜正＞Homeostasis in internal environment and cellular metabolism ensures cells’functions to be stable in living *** spike encoding in the brain needs to be precise and

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河流沉积物重金属污染质量控制基准的研究 Ⅰ.C-B-T质量三合一方法(Triad)

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环境科学学报 1999年第2期 10-16页

作者： (SKLEAC,Research Center for Eco Environmental sciences,chinese {2. of sciences,beijing 100085)

在综合数据库ＣＥＲＰＤＢＭＳ支持下，利用水体沉积物质量三合一工具（Ｔｒｉａｄ），初步建立江西乐安江表层沉积物中重金属污染的质量控制基准（ＳＱＣ）．通过将化学分析（Ｃ）、毒性鉴定（Ｔ）和底栖群落结构变化（Ｂ）三基元集... 详细信息

在综合数据库ＣＥＲＰＤＢＭＳ支持下，利用水体沉积物质量三合一工具（Ｔｒｉａｄ），初步建立江西乐安江表层沉积物中重金属污染的质量控制基准（ＳＱＣ）．通过将化学分析（Ｃ）、毒性鉴定（Ｔ）和底栖群落结构变化（Ｂ）三基元集成为一体的三轴图和相应的响应信息判断矩阵，基于现场生物响应的沉积物质量基准能较为清晰地指示乐安江流域表层沉积物中重金属污染的相对程度和分布模式，体现底栖生物对沉积物重金属污染的剂量响应关系，为进一步制订该区域沉积质量管理标准（ＳＱＳ）、开展后续的污染治理与恢复工程提供技术保证和科学依据．

关键词：沉积物质量基准(SQC) 质量三合一法(Triad) 重金属乐安江

An emergy evaluation of the seven years’development of Qianyanzhou ecological experimental station

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Journal of Geographical sciences 1998年第3期8卷 20-35页

作者： YAN Maichao Commission for Integrated Survey of Natural Resources, chinese academy of {2., {3. 100101 china H T O dum Center for Environmental Policy, Department of Environmental Engineering {2., University of Florida, Gainesville,

An emergy (spelled with an “m”) evaluation of Qianyanzhou ecological station was performed in order to study its progress during 7 years' development, using changes of emergy inputs and outputs Emergy indices of Qianyanzhou were evaluated and compared with those from other countries The comparison showed that Qianyanzhou may be developing optimum use of its natural resources

关键词： emergy Qianyanzhou comparative analysis

Naturally-formed objects categorized as artifacts:Effect of objects' functional depictions

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Science Bulletin 2010年第Z1期 398-403页

作者： SUN YuHao1,2. WANG Zhe1, LIU Ye2.& FU XiaoLan2.Department of Psychology, Zhejiang Sci-Tech University, Hangzhou 3.0018,{3. 2.tate Key Laboratory of Brain and Cognitive Science, Institute of Psychology, chinese {2. of sciences, beijing 100101,{3.

Past research has identified a variety of factors that influence cognitive processing of artifact concepts, but few experiments tested possible interactive patterns among these factors. Using a natural language depiction based free naming task, we explored how an object's function and its history (information about how an object was formed by natural force) interact to affect categorization judgment in a 2.2.betweensubjects experiment (N = 169). The study had two key findings: (i) Without presenting an object's function, presenting the history of its natural formation increased subjects' tendency to name the object under the "natural" domain and decreased their tendency to name it under the "artifact" domain; (ii) once we presented the depiction of an object's function, the effect of history presentation on categorization disappeared:Subjects in both conditions strongly preferred naming objects as artifacts. In summary, presenting depiction of an object's function inhibited the effect of history on object categorization. Current findings suggest that an object's function plays a fundamental role in the cognitive processing of artifact concepts.

关键词： artifacts categorization design history function