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ADVANCED SYNTHESIS OF LIGHT METALS

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Acta Metallurgica Sinica(English Letters) 1996年第6期9卷 531-536页

作者： F.H. Froes(IMAP, University of Idaho, Moscow, ID 838443026, usa ) Univ of Idaho Moscow United States

The synthesis, processing and mechanical properties of the light metals, aluminum,magnesium and titanium Produced by advanced techniques are reviewed. Synthesis techniques to be addressed will include rapid solidifica... 详细信息

关键词： synthesis/processing powder metallurgy lightweight metals,aluminum magnesium,titanium rapid solidification spray depositin mechanical alloying Plasma processing,vapor deposition

SYMPLECTIC SCHEMES FOR QUASILINEAR WAVE EQUATIONS OF KLEIN-GORDON AND SINE-GORDON TYPE

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Journal of Computational Mathematics 2001年第5期19卷 475-488页

作者： Xiao-wu Lu (Department of Mathematics and Computer Science, Emory University, Atlanta, GA 30322, usa) Emory University 美国 30322

Presents a class of finite difference methods of first and second order accuracy for the computation of solutions to the quasilinear wave equations. Overview of general symplectic schemes and generating functional; Nu... 详细信息

关键词： Symplectic integration Sine-Gordon equations Finite difference method.

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

Energetics and Propagation of Coronal Mass Ejections in Different Plasma Environments

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Chinese Journal of Astronomy and Astrophysics 2002年第6期2卷 539-556页

作者： Jun LinHarvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138, usa Harvard-Smithsonian Center for Astrophysics 60 Garden Street Cambridge MA 02138 USA

Based on previous work, we investigate the propagation of CMEs in a more realistic plasma environment than the isothermal atmosphere, and find that it is a slightly faster reconnection for flux ropes to break free. The average Alfven Mach number MA for the inflow into the reconnection site has to be at least 0.013 in order to give a plausible eruption (compared to MA = 0.005 for the isothermal atmosphere). Taking MA = 0.1, we find that the energy output and the electric field induced inside the current sheet match the temporal behavior inferred from the energetic, long duration, CME-associated X-ray events. The results indicate that catastrophic loss of equilibrium in the coronal magnetic field provides the most promising mechanism for major solar eruptions, and that the more energetic the eruption is, the earlier the associated flare peaks. The variation of the output power with the background field strength revealed by our calculations implies the poor correlation between slow CMEs and solar flares. This work also further confirms the explanation we proposed for the peculiar motion of giant X-ray arches and anomalous post-flare loops. Their kinematic pattern and observed heights are determined by the local Alfven speed and its variation with height.

关键词： Sun: CMEs - Sun: atmosphere - Sun: magnetic fields

POLES OF ZETA FUNCTIONS OF COMPLETE INTERSECTIONS

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Chinese Annals of Mathematics,Series B 2000年第2期21卷 187-200页

作者： WAN DAQING(Department of Mathematics, University of California, Irvine, CA 92697-3875, usa.) Department of Mathematics University of California Irvine CA 92697-3875 USA

A vanishing theorem is proved for e-adic cohomology with compact support on an affine (singular) complete intersection. As an application, it is shown that for an affine complete intersection defined over a finite field of q elements, the reciprocal "poles" of the zeta function are always divisible by q as algebraic integers. A p-adic proof is also given, which leads to further q-divisibiliy of the poles or equivalently an improvement of the polar part of the AxKatz theorem for an affine complete intersection. Similar results hold for a projective complete intersection.

关键词： Pole Zeta function Complete intersection

Causation Analysis on Urban Transportation Problems in Shanghai

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China City Planning Review 2009年第4期18卷 58-62页

作者： YU Xin, MSCE Candidate, Department of Civil and Environmental Engineering, University of Hawaii, Honolulu, HI, usa.

1. Introduction Shanghai, a major commercial and industrial center of China, is located on the Yangtze River Delta in East China (see Fig. 1). It is one of the

关键词： traffic Yangtze transportation facilities congesti

Application of a Latest Manipulation, Stroking of Massage

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中国针灸 1995年第S2期15卷 359-360页

作者： Wang Xiaoping(California,usa)

ＡｐｐｌｉｃａｔｉｏｎｏｆａＬａｔｅｓｔＭａｎｉｐｕｌａｔｉｏｎ，ＳｔｒｏｋｉｎｇｏｆＭａｓｓａｇｅ￥ＷａｎｇＸｉａｏｐｉｎｇ（Ｃａｌｉｆｏｒｎｉａ，ＵＳＡ）Ｆｏｒｍａｎｙｙｅａｒｓ，ｍａｎｙｄｏｃｔｏｒｓｏｆｔｅｎ... 详细信息

ＡｐｐｌｉｃａｔｉｏｎｏｆａＬａｔｅｓｔＭａｎｉｐｕｌａｔｉｏｎ，ＳｔｒｏｋｉｎｇｏｆＭａｓｓａｇｅ￥ＷａｎｇＸｉａｏｐｉｎｇ（Ｃａｌｉｆｏｒｎｉａ，ＵＳＡ）Ｆｏｒｍａｎｙｙｅａｒｓ，ｍａｎｙｄｏｃｔｏｒｓｏｆｔｅｎｕｓｅｌｏｏｓｅｎｉｎｇａｎｄｍｏ...

关键词： Application of a Latest Manipulation Stroking of Massage

ON THE KINEMATIC GEOMETRY OF MANY BODY SYSTEMS

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Chinese Annals of Mathematics,Series B 1999年第1期20卷 11-28页

作者： WU-YI HSIANG(Department of Mathematics,University of CALIFORNIA,berkeley,CA 94720-3840,usa) Univ Calif Berkeley Dept Math Berkeley CA 94720 USA

In mechanics, both classical and quantum, one studies the profound interaction betweentwo types of energy, namely, the kinetic energy and the potential energy. The former can beorganized as the kinematic metric on the configuration space while the latter can be representedby a suitable potential function, such as the Newtonian potential in celestial mechanics andthe Coulomb potential in quantum mechanics of atomic and molecular physics. In this paper,the author studies the kinematic geometry of n-body systems. The main results are (i) theintroduction of a canonical coordinate svstem which reveals the total amount of kinematicsymmetry by an SO(3) x O(n-1) action in such a canonical coordinate representationt (ii) anin depth analysis of the above kinematic system both in the setting of classical invariant theoryand by the technique of equivariant Riemannian geometry; (iii) a remarkably simple formulafor the potential function in such a canonical coordinate system which reveals the well-fittingbetween the kinematic symmetry and the Potential energy.

关键词： Kinematic geometry Many body system Configuration space

Parameterization of the Non-Local Thermodynamic Equilibrium Source Function with Chemical Production by an Equivalent Two-Level Model

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Advances in Atmospheric Sciences 2003年第4期20卷 487-495页

作者： Xun ZHUThe Johns Hopkins University Applied Physics Laboratory, MD 20723-6099, usa Applied Physics Laboratory The Johns Hopkins University 20723-6099 MD USA

The classic two-level or equivalent two-level model that includes only the statistical equilibrium of radiative and thermal processes of excitation and quenching between two vibrational energy levels is extended by adding chemical production to the rate equations. The modifications to the non-local thermodynamic equilibrium source function and cooling rate are parameterized by ϕc, which characterizes the ratio of chemical production to collisional quenching. For applications of broadband emission of O3 at 9.6 μm, the non-LTE effect of chemical production on the cooling rate and limb emission is proportional to the ratio of O to O3. For a typical [O]/[O3], the maximum enhancements of limb radiance and cooling rate are about 15%–30% and 0.03–0.05 K day−1, respectively, both occurring near the mesopause regions. This suggests that the broadband limb radiance above ∼80 km is sensitive to O3 density but not sensitive to the direct cooling rate along the line-of-sight, which makes O3 retrieval feasible but the direct cooling rate retrieval difficult by using the O3 9.6 μm band limb emission.

关键词： non-LTE radiative transfer ozone cooling ozone retrieval space weather