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101.
应用等效原理,通过引入口面上等效磁流将含腔导电目标电磁散射简化为腔内、外两个等效 问题. 腔内问题分段求解并应用级联法获得口面等效导纳矩阵;腔内外的耦合关系应用近似 边界元方法描述并由此获得口面等效磁流;最后,这一具有混合源的腔体内外一体化散射问 题则应用所提出的广义混合场积分方程方法建立电磁模型,并用多层快速多极子方法实现高 效数值求解. 实例计算结果与测试结果具有很好的一致性.
关键词:
含腔目标
电磁散射
混合场积分方程
数值分析 相似文献
103.
A new estimation based on the Shannon entropy for the power-law distribution parameter is presented, The maximum likelihood estimation (MLE) of the parameter is discussed and the relation between the MLE and the moment estimation of the parameter is given out. It is shown that the minimum Shannon entropy estimation is equivalent to the MLE giving the log expectation. 相似文献
104.
Tatsien LI 《数学年刊B辑(英文版)》2007,28(3):265-282
In this paper, the authors consider the inverse piston problem for the system of one-dimensional isentropic flow and obtain that, under suitable conditions, the piston velocity can be uniquely determined by the initial state of the gas on the right side of the piston and the position of the forward shock. 相似文献
105.
106.
By means of a formal analogy with the Aharonov-Bohm effect, the Sagnac time delay and the corresponding Sagnac phase shift in the Kerr-Newman and Reissner-Nordstrfm spacetimes are discussed. We find that the effect depends on the properties of the source of the gravitational field. The contributions made by the electric charge of the gravitational source can be employed to weaken it in the Kerr-Newman spacetime, even if a phase shift and a time delay still appear. This is due to the properties of the rotating source of the gravitational field. 相似文献
107.
Bistable Behaviour of N Two-Level Atoms Interacting with the Field inside a High-Q Cavity Containing a Nonlinear Kerr-Like Medium 下载免费PDF全文
Taking the intensity-dependent coupling between atoms and cavity mode into account, we investigate a system consisting of N homogeneously broadened two-level atoms interacting with the field inside a single-mode Fabry- Perot cavity containing a nonlinear Kerr-like medium. We derive the steady-state bistable behaviour of the system, and further analyse in details the influence of several critical parameters on the bistable behaviour. 相似文献
108.
The fission barrier for ^240pu is investigated beyond the second saddle point in the potentiM energy surface by the constrained relativistic mean field method with the newly proposed parameter set PK1. The microscopic correction for the centre-of-mass motion is essentiM to provide the correct potential energy surface. The shell effects that stabilize the nuclei against the fission is also investigated by the Strutinsky method. The shapes for the ground state, fission isomer and saddle-points, etc, are studied in detail. 相似文献
109.
钱塘江河口潮流错综复杂.依靠零星的实测潮流资料无法全面描述其流场特征.本文采用Dcldt3D模型对钱塘江河口闻家堰至仓前河段的潮流场进行二维数值模拟.着重研究了河口弯道的流场特性.结果表明.河口弯道流场具有跟无潮河流弯道显著不同的特性.如弯道流速向下游递增;涨、落急主流线分歧;涨、落潮流对丁坝工程的响应不同.以及下游弯道水面横比降大于上游弯道. 相似文献
110.
Hongyi Chen Chunguang Du Shiqun Li 《量子光学学报》2006,12(B08):77-78
Recently, research on left-handed materials (LHMs) has attracted considerable attentions. The LHMs are a kind of man-made metameterials which have negative permittivity and negative permeability. These metameterials have many novel properties such as inverse light pressure, and reverse Doppler effect, which lead to many potential applications of LHMs such as superlenses which, in principle, can achieve arbitrary subwavelength resolution. However, though the properties mentioned above are seen to be classical, the quantum phenomena in LHMs have also attracted attentions such as the modified spontaneous emission of atoms in LHME. 相似文献