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91.
92.
We derive and analyse four algorithms for computing the current induced on a thin straight wire by a transient electric field.
They all involve solving the thin wire electric field integral equations (EFIEs) and consist of a very accurate differential
equations solver together with various schemes to approximate the vector potential integral equation. We carry out a rigorous
numerical stability analysis of each of these methods. This has not previously been done for solution schemes for the thin
wire EFIEs. Each scheme is shown to be stable and convergent provided the radius of the wire is small enough for the thin
wire equations to be a valid model. 相似文献
93.
Hans C. Fogedby 《Journal of statistical physics》1992,69(1-2):411-425
We elaborate in some detail on a new phase space approach to complexity, due to Y.-C. Zhang. We show in particular that the connection between maximal complexity and power law noise or correlations can be derived from a simple variational principle. For a 1D signal we find 1/f noise, in accordance with Zhang. 相似文献
94.
95.
Xiangdong Liu Hongwei Liu Kexu Yuan Huiping Du 《International Journal of Infrared and Millimeter Waves》1991,12(9):1023-1034
According to the angular-spectrum method, a radiation beam of an antenna horn in the Fresnal region is decomposed into the plane waves with the fast Fourier transform algorithm and the waves diffracted from a reflection grating are superposed as a diffracted beam. Compared with the reflected beam from the same size mirror, the radiation half width of the diffracted beam from a grating is narrower and its lateral shape is shift. These performances have been experimentally verified at Ka-band by: (1). The relative diffraction efficiencies in the first order with two triangular gratings which is put along propagating direction of a beam produced by a conical lens-horn. (2). H-plane lateral width with power—3dB lapsed of the focus beam from a grating and a mirror in a grating spectrometer for millimeter waves (25–100 GHz). 相似文献
96.
Zi‐Cai Li Tzon‐Tzer Lu Hung‐Tsai Huang Alexander H.‐D. Cheng 《Numerical Methods for Partial Differential Equations》2007,23(1):93-144
In this article we survey the Trefftz method (TM), the collocation method (CM), and the collocation Trefftz method (CTM). We also review the coupling techniques for the interzonal conditions, which include the indirect Trefftz method, the original Trefftz method, the penalty plus hybrid Trefftz method, and the direct Trefftz method. Other boundary methods are also briefly described. Key issues in these algorithms, including the error analysis, are addressed. New numerical results are reported. Comparisons among TMs and other numerical methods are made. It is concluded that the CTM is the simplest algorithm and provides the most accurate solution with the best numerical stability. © 2006 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2007 相似文献
97.
We exhibit a characteristic structure of the class of all regular graphs of degree d that stems from the spectra of their adjacency matrices. The structure has a fractal threadlike appearance. Points with coordinates given by the mean and variance of the exponentials of graph eigenvalues cluster around a line segment that we call a filar. Zooming-in reveals that this cluster splits into smaller segments (filars) labeled by the number of triangles in graphs. Further zooming-in shows that the smaller filars split into subfilars labeled by the number of quadrangles in graphs, etc. We call this fractal structure, discovered in a numerical experiment, a multifilar structure. We also provide a mathematical explanation of this phenomenon based on the Ihara-Selberg trace formula, and compute the coordinates and slopes of all filars in terms of Bessel functions of the first kind. 相似文献
98.
99.
In the paper we indicate an error made in the proof of the main result of the paper [M.A. Darwish, On quadratic integral equation of fractional orders, J. Math. Anal. Appl. 311 (2005) 112-119]. Moreover, we provide correct proof of a slightly modified version of the mentioned result. The main tool used in our proof is the technique associated with the Hausdorff measure of noncompactness. 相似文献
100.
在为期权定价时,使用B-S公式算得的结果和市场交易值存在一定偏差.本文针对这一问题,给出了一种新的期权定价数值方法,即局部线性预测法.并用股票期权的实际交易数据对这一方法进行了数值验证,表明这一方法是有效的. 相似文献