共查询到20条相似文献,搜索用时 78 毫秒
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以简支矩形板为例,分析结构振动模态之间的耦合对声功率的影响。通过对声功率传递矩阵计算方法的改进,得到计算声功率传递矩阵对角元素和非对角元素(模态耦合项)的解析解,并进行数值计算和分析。所得解析解结果同前人发表的数值解非常吻合。 相似文献
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用普通Korteweg-de Vries(KdV)方程作变换,构造(3 1)维KdV方程的解,获得了新的孤子解、Jaoobi椭圆函数解、三角函数解和Weierstrass椭圆函数解. 相似文献
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利用推广的齐次平衡方法,首先将(2+1)维Broer-Kaup方程线性化,然后构造出丰富的广义孤子解,包括单孤子解,单曲线孤子解,单dromion解,多dromion解。此方法直接而简单,可推广应用一大类(2+1)维非线性可积方程。 相似文献
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采用行波法约化方程,建立一种变换关系,把求解(3+1)维NizhnikNovikovVeselov(NNV)方程的解转化为求解一维非线性KleinGordon方程的解,从而得到了(3+1)维NNV方程的孤子解和周期解.
关键词:
(3+1)维Nizhnik-Novikov-Veselov方程
非线性Klein-Gordon方程
孤子解
周期解 相似文献
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借助于符号计算软件Maple,通过一种构造非线性偏微分方程(组)更一般形式精确解的直接方法即改进的代数方法,求解(2+1) 维 Broer-Kau-Kupershmidt方程,得到该方程的一系列新的精确解,包括多项式解、指数解、有理解、三角函数解、双曲函数解、Jacobi 和 Weierstrass 椭圆函数双周期解.
关键词:
代数方法
(2+1) 维 Broer-Kau-Kupershmidt 方程
精确解
行波解 相似文献
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利用Hirota方法及Riemann theta函数得到了(2+1)维Boussinesq方程的新的周期解.在极限情况下,该周期解退化为孤子解.
关键词:
Hirota方法
Riemann theta 函数
(2+1)维Boussinesq方程
周期解 相似文献
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LEED analysis of the laser annealed Si(1 1 1)-(1 × 1) surface shows that a model with a graphite-like top double layer of atoms with a spacing of 2.95±0.02 Å from the second double layer describes the LEED data as well as the Zehner model, but involves large displacements of the atoms normal to the surface as required by ion scattering results. It is suggested that this model provides a natural interpretation of the low energy He atom scattering data for the Si(1 1 1)-(7 × 7) surface. 相似文献
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We give an explicit construction of the -cocycles of the group of contactomorphisms on the supercircle for , with coefficients in the space of differential operators acting on -tensor densities. We show that they satisfy properties similar to those of the super-Schwarzian derivative. 相似文献
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The method of “averaging” is often used in Hamiltonian systems of two degrees of freedom to find periodic orbits. Such periodic orbits can be reconstructed from the critical points of an associated “reduced” Hamiltonian on a “reduced space”. This paper details the construction of the reduced space and the reduced Hamiltonian for the semisimple 1:1 resonance case. The reduced space will be a 2-sphere in R3, and the reduced differential equations will be Euler's equations restricted to this sphere. The orbit projection from the energy surface in phase space to this sphere will be the Hopf map. The results of the paper are related to problems in physics on “degeneracies” due to symmetries of classical two-dimensional harmonic oscillators and their quantum analogues for the hydrogen atom. 相似文献
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We present measurements of infrared inter-subband absorption for electron subbands on (1 1 1)-Si for densities Ns up to ~ 1013 cm?2 at 4.2 K for both parallel- and perpendicular-excitation geometries. Contrary to previously published work the depolarization shift is identified as a sizeable splitting of the resonance energies E⊥01 and Ez.dfnc;01. The comparison with a recent calculations is given. 相似文献
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Peter Dek Carlos R. Ortiz Lawrence C. Snyder James W. Corbett 《Physica B: Condensed Matter》1991,170(1-4):223-226
The stability of hydrogen complexes aligned in a (1 1 1) plane of silicon is studied theoretically. Pairs of hydrogen atoms saturating broken bonds between adjacent planes are found to be the most stable arrangement with the heat of formation increasing as the platelet grows. The related stress is estimated and electronic effects are discussed. 相似文献
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Ag(1 1 1) monolayers prepared on two substrates, Ni(1 1 1) and Ni(0 0 1), were studied with angle-resolved photoemission; their two-dimensional band dispersions were found to be identical within experimental uncertainties. Comparing the present results with those for Ag/Cu(0 0 1), the major difference is just a shift of 0.32 eV in all the binding energies. Thus the band topology of Ag overlayers in these systems is quite insensitive to the electronic and atomic structures of the substrates. 相似文献
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Diffusion of dysprosium on the (1 1 1) facet of a tungsten micromonocrystal was investigated by means of spectral analysis of field emission current fluctuations. The experimental spectral density functions of the current fluctuations were analysed by using Gesley and Swanson’s theoretical spectral density function, which enables to determine the surface diffusion coefficient D for dysprosium. Derived from the temperature dependence of D, the diffusion activation energy E is presented for some Dy coverages θ(1 1 1). In the temperature range 400–600 K, the E first drops from 1.25 eV per atom at θ(111)≈0.25 ML to 0.48 eV per atom at θ(111)≈1 ML (corresponding to the minimum of the work function of the system), then increases to 1.03 eV per atom at θ(111)≈1.3 ML. The results are discussed from the aspects of the substrate structure and interaction in the adsorbed layer. 相似文献
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We report our observations of the features in the conductivity and the anomalous magnetoresistance of a two-dimensional hole gas near (1 1 1) silicon surface, which gives the evidence for the onset of the second subband occupation at hole density ps ≈ 5.3 × 1012 cm-2. 相似文献
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We present the first direct observation of an occupied noble metal surface state at the metal/liquid interface. The Au(1 1 1) Shockley-like surface state was measured by scanning tunneling spectroscopy (STS) at the Au(1 1 1)/n-tetradecane interface. These results show that the surface state of gold survives in a liquid environment, and can be probed by STS. More generally it indicates that STS can be used to study electronic properties of surfaces at the solid/liquid interface, and that spectra can be directly compared to measurements and calculations of a surface’s electronic structure in ultra-high vacuum. 相似文献
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Armstrong TA Bettoni D Bharadwaj V Biino C Borreani G Broemmelsiek D Buzzo A Calabrese R Ceccucci A Cester R Church M Dalpiaz P Dalpiaz PF Dibenedetto R Dimitroyannis D Fabbri MG Fast J Gianoli A Ginsburg CM Gollwitzer K Hahn A Hasan M Hsueh S Lewis R Luppi E Macrí M Majewska AM Mandelkern M Marchetto F Marinelli M Marques J Marsh W Martini M Masuzawa M Menichetti E Migliori A Mussa R Palestini S Pallavicini M Pastrone N Patrignani C Peoples J Pesando L Petrucci F Pia MG Pordes S Rapidis P 《Physical review letters》1992,69(16):2337-2340