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Superplasticity of Mg-5.8Zn-1Y-Zr alloy sheet fabricated by combination of extrusion and hot-rolling processes

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中国科学:技术科学 2010年第4期 454-454页

作者： YAN Hong 1,2,CHEN RongShi 1 & HAN EnHou 1 1 State Key Laboratory for Corrosion and Protections,institute of Metal Research,chinese academy of sciences,Shenyang 110016,china 2 Graduate University of chinese academy of sciences,beijing 100049,china

Superplastic behaviors of quasicrystal phase containing Mg-5.8Zn-1Y-0.48Zr alloy sheets fabricated by combination of extrusion and hot-rolling processes have been investigated at temperature ranging from 623 to 753 K and at the strain rates ranging from 10 -4 to 10 -2 s -1 by uniaxial tensile *** excellent superplasticity with the maximum elongation to failure of 1020%was obtained at 753 K and the strain rate of 1.04×10-3s -1and its strain rate sensitivity,m,is as high as up to 0.75. The microstructure was stable during superplastic deformation due to the uniformly distributed fine quasicrystal particles. In addition,micro-cavities and their coalescences were observed in the superplastic deformation of the ZW61 magnesium *** boundary sliding(GBS)was considered to be the main deformation mechanism during the superplastic *** creep controlled by atom diffusion through grain boundaries or interior grains is suggested mainly to accommodate the GBS in superplastic deformation.

关键词： magnesium alloy quasicrystal microvoid superplasticity

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回归现实生活——哲学视野的根本置换

学习与探索 2001年第1期 11-17页

作者：李文阁中国社会科学院哲学所北京100732

近代哲学是一种科学世界观 ,现代哲学则是一种生活世界观。从近代哲学到现代哲学 ,即是从科学世界回归生活世界 ,从本质主义转向生成性思维。回归生活世界是现代哲学的基本精神。现代西方哲学家们所理解的生活世界只是人的日常生活或日... 详细信息

近代哲学是一种科学世界观 ,现代哲学则是一种生活世界观。从近代哲学到现代哲学 ,即是从科学世界回归生活世界 ,从本质主义转向生成性思维。回归生活世界是现代哲学的基本精神。现代西方哲学家们所理解的生活世界只是人的日常生活或日常的语言交往 ;而马克思认为生活世界是以实践为基础的 ,是日常生活与非日常生活、物质生活与精神生活的统一。

关键词：科学世界生活世界本质主义生成性思维

Precise recognition of warhead and decoy based on components of micro-Doppler frequency curves

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Science china(Information sciences) 2012年第4期55卷 850-856页

作者： GUO KunYi & SHENG XinQing Center for Electromagnetic Simulation,School of Information and Electronics,beijing institute of Technology,beijing 100081,china 1. Center for Electromagnetic Simulation School of Information and Electronics Beijing Institute of Technology Beijing 100081 China

From the view of electromagnetic scattering,it is indicated that the micro-Doppler (m-D) character-istics of an extended target undergoing micro-motions are actually induced by the change of incident directions of radar *** micro-motions may lead to similar change of incident directions,consequently inducing similar m-D *** tackle this problem,rather than distinguish warhead and decoy directly from m-D characteristics,the frequency components of m-D frequency curves are used as a new characteristic for recognition in this *** get high precision of frequency components estimation,model-based parameter estimation (MBPE) is utilized to extract the m-D frequency curves from *** obtain high accurate simu-lation results,the backscattered signal simulation is conducted by full-wave numerical *** simulation results validate the theoretical analysis and the high performance of the proposed method.

关键词： micro-Doppler(m-D) target recognition time-frequency representation (TFR) model-based pa-rameter estimation (MBPE)

最后的绝唱:1948年前后关于自由主义的讨论

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四川大学学报（哲学社会科学版） 2008年第4期 46-56页

作者：左玉河中国社会科学院近代史研究所北京100000

1948年1月,《大公报》发表了社评《自由主义者的信念》,在中国思想界迅速引起了一场关于自由主义的讨论。这场讨论,内容涉及广泛,讨论的双方就个人自由与大众民主关系、计划经济与思想自由关系、革命与改良的关系、自由获得方式等问题... 详细信息

1948年1月,《大公报》发表了社评《自由主义者的信念》,在中国思想界迅速引起了一场关于自由主义的讨论。这场讨论,内容涉及广泛,讨论的双方就个人自由与大众民主关系、计划经济与思想自由关系、革命与改良的关系、自由获得方式等问题展开了激烈的争论。在国家命运面临抉择之时,《大公报》树起"自由主义"旗帜,显示了难得的道德勇气和批判精神,堪称中国自由主义的"绝唱"。

关键词：自由主义《大公报》中国前途中间路线

Digital Ocean Oriented Data Processing and Information Service Systems

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Digital Ocean Oriented Data Processing and Information Servi...

Joint exploration of crustal structure in Fuzhou basin and its vicinities by deep seismic reflection and high-resolution refraction as well as wide-angle reflection/refraction

第二十七届中国控制会议

作者： Wang Xiaomin 1,2,Zhang Xin 1,Chi Tianhe 1 1.institute of Remote Sensing Applications,chinese academy of sciences,beijing 100101,P.R.china 2.Graduate University of chinese academy of sciences,beijing 100039,P.R.china

Digital Ocean is one of important digital industries based on the concept of Digital *** a macro complex systematic engineering,the Digital Ocean is an ongoing task in *** mission of the Digital Ocean is to build an information system and develop methods for creating digital representations,or models,of ocean variables and *** gathering,processing,analyzing,visualizing and making data and information widely available,the Digital Ocean project can help provide integrated information on historical,current and future states of ocean and coastal *** paper analyzes data acquisition and information requirements of Digital *** on the analysis of the information needs,the data processing chain and methods of the Digital Ocean are brought *** then it presents two Digital Ocean oriented information service systems,one-stop portal based information services system for IOOS of Taiwan strait and 3-D globe based Digital Ocean prototype.

关键词： Digital ocean Data processing Information service systems

来源： cnki会议评论

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Science china Earth sciences 2005年第7期48卷 925-938页

作者： ZHU Jinfang1, XU Xiwei2, ZHANG Xiankang3, HUANG Zonglin1, CHEN Xiangxiong1, FANG Shengming3, LIU Baojin3, ZHENG Rongzhang2,4 1. Seismological Bureau of Fujian Province,Fuzhou 350003,china 2. institute of Geology,china Earthquake Administration,beijing 100029,china 3. Research Center for Exploration Geophysics,china Earthquake Administration,Zhengzhou 450002,china 4. State Key Laboratory of Earthquake Dynamics,institute of Geology,china Earthquake Administration,beijing 100029,china Seismological Bureau of Fujian Province Fuzhou 350003 China institute of Geology China Earthquake Administration Beijing 100029 China Research Center for Exploration Geophysics China Earthquake Administration Zhengzhou 450002 China State Key Laboratory of Earthquake Dynamics Institute of Geology China Earthquake Administration Beijing 100029 China

The Fuzhou basin and its vicinities are located at the northern end of the southeastern coastal seismic zone of the mainland of china. By the joint explorations of high-resolution seismic refraction and wide-angle reflection/refraction as well as deep seismic reflection in the region, which is the first synthetic profile in china, its fine velocity structure and geometric structure from the ground to Moho discontinuity is obtained. The result shows that the crust is obviously layered with a thickness of about 32 km. Basically, it consists of two parts: upper crust and lower crust. The velocity of the upper crust is 5.9-6.2 km/s in which there is a 3-4-km-thick weak low-velocity layer between the depths of 10-15 km, while the velocity of the lower crust in the range of 6.3-7.2 km/s. There exists a strong velocity gradient layer about 3 km thick above the Moho discontinuity whose velocity increases from 6.5 to 7.27 km/s. There exist high-angle normal faults that are small in size and extend only in the shallow crust. These faults are the secondary developed on the hanging wall of westward dipping low-angle normal faults. Thus, their seismogenic ability is limited, however, there exists a high-angle deep fault in the crust from Changle-Zaoan fault zone to seashore fault zone. This deep fault has cut the interface between the upper and lower crusts and Moho discontinuity, and may be the deep structure to trigger destructive earthquake source in future to affect Fuzhou City. These results have advanced the detecting precision of the deep structure in the southeastern coastal seismic zone of the mainland of china. In the aspect of the combined feature of the deep and shallow extensional structures that consist of the westward dipping low-angle normal faults and secondary normal faults on their hanging walls in the upper crust, it is firstly obtained that a united structural interpretation has deepened the knowledge about the deep dynamic process in the southeastern coasta

关键词： deep seismic reflection high-resolution seismic refraction wide-angle.

Weak Morrey spaces and strong solutions to the Navier-Stokes equations

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Science china Mathematics 2007年第10期50卷 1401-1417页

作者： Chang-xing MIAO~(1+) Bao-quan YUAN~2 ~1 institute of Applied Physics and Computational Mathematics,P.O.Box 8009,beijing 100088,china ~2 College of Mathematics and Informatics,Henan Polytechnic University,Jiaozuo 454000,china 1. institute of Applied Physics and Computational Mathematics P.O. Box 8009 Beijing 100088 China 2. College of Mathematics and Informatics Henan Polytechnic University Jiaozuo 454000 China

We consider the Cauchy problem of Navier-Stokes equations in weak Morrey *** first define a class of weak Morrey type spaces M_(p,λ)~*(R^n)on the basis of Lorentz space L_(p,∞)=L_p~*(R^n) (in particular,M_(?)~*(R^n)=L_(p,∞),if p>1),and study some fundamental properties of them;Second, we prove that the heat operator U(t)= e^(tΔ)and Calderón-Zygmund singular integral operators are bounded linear operators on weak Morrey spaces,and establish the bilinear estimate in weak Morrey ***,by means of Kato's method and the contraction mapping principle,we prove that the Cauchy problem of Navier-Stokes equations in weak Morrey spaces M_(p,λ)~*(R^n)(1

关键词： Navier-Stokes equations, weak Morrey spaces, Lorentz spaces, Cauchy problem,time-global well-posedness, self-similar solutions

Design and Experiments of a Robotic Fish Imitating Cow-Nosed Ray

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Journal of Bionic Engineering 2010年第2期7卷 120-126页

作者： Yueri Cai,Shusheng Bi,Licheng Zheng Robotics institute,Beihang University,beijing 100191,P.R.china [a] Robotics institute Beihang University Beijing 100191 P. R. China

The cow-nosed ray is studied as natural sample of a flapping-foil robotic *** structure, motion discipline, and dynamicfoil deformation of cow-nosed ray are *** on the analysis results, a robotic fish imitating cow-nosed ray,named Robo-ray Ⅱ, mainly composed of soft body, flexible ribs and pneumatic artificial muscles, is *** andswimming morphology of the robotic prototype are as that of a normal cow-nosed ray in *** propulsion parameters ofRobo-ray Ⅱ at normal conditions, including the St Number at linear swimming, thrust coefficient at towing are studied *** suitable driving parameters are confirmed considering the efficiency and swimming *** of 0.16 m·s’and thrust coefficient of 0.56 in maximum are achieved in experiments.

关键词： robotic fish cow-nosed ray flexible structure St Number thrust coefficient

EXPERIMENTAL STUDY ON FLOW AND SEDIMENT MOVEMENT IN CAVITY CIRCULATIONS

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International Journal of Sediment Research 2002年第2期17卷 147-156页

作者： Qingquan LIU1 1 Prof., institute of Mechanics, chinese academy of sciences, beijing 100080, china. E-mail: qqliu@*** Prof. Institute of Mechanics Chinese Academy of Sciences Beijing 100080 China

This paper reports a flume experiment of flow and sediment movement in a cavity. The flow velocity, sediment concentration and the mechanism of hydraulic sorting in the circulation flow are discussed. The quantity and... 详细信息

关键词： Cavity circulation Radial circulation Flow velocity Sediment concentration Deposition