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排序方式: 共有228条查询结果,搜索用时 15 毫秒
1.
In this paper, we give a unified construction of the recursion operators from the Lax representation for three integrable hierarchies: Kadomtsev–Petviashvili (KP), modified Kadomtsev–Petviashvili (mKP) and Harry Dym under n-reduction. This shows a new inherent relationship between them. To illustrate our construction, the recursion operator are calculated explicitly for 2-reduction and 3-reduction.  相似文献   
2.
This note generalizes the well-known Leibnitz rule of successive differentiation for the product of two functions to a similar result for the product of three functions.  相似文献   
3.
4.
本文应用拉普拉斯变换得到了三维各向同性谐振子波函数边界的精确解,同时,利用同种方法还得到了利用产生算符和湮灭算符表达的该波函数的递推关系.  相似文献   
5.
递推与迭代在量子力学近似计算中的应用   总被引:1,自引:0,他引:1  
综述了非简并微扰论和简并微扰论的递推形式,一维阶梯位势透射系数的递推计算及变化法的迭代形式,在给定的精度下,利用上述方法可以得到与精确解完全一致的效果。  相似文献   
6.
For the 2 × 2 nonuniform micro-scanning, of which the interframe displacement is no longer equivalent to accurate half-pixel, a sub-pixel processing algorithm based on boundary recursion and error optimization is proposed in this paper. Boundary recursive technique is introduced to solve the ill-posed problem in the process of nonuniform micro-scanning sub-pixel image reconstruction, but the manually predefined boundary values in boundary recursion inevitably result in error. Aiming at eliminating the error in boundary recursion, error optimization based on gray statistical principle is used in this paper. All the simulation results and experiment data show that the algorithm proposed in this paper can realize accurate sub-pixel imaging and improve image resolution. The algorithm is robust, simple and effective, and it is hopeful to be used in actual system.  相似文献   
7.
渐变折射率波导传播特性微扰计算的代数递推公式   总被引:5,自引:2,他引:3  
应用量子力学的超位力定理(HVT)和赫尔曼-费恩曼(Hellmann-Feynman)定理(HFT),导出了用微扰法计算渐变折射率平面波导传播常数各级近似值的代数递推公式,并给出了由传播常数近似值计算模场近似表达式的代数式。计算了几个典型实例,此法的特点是便于直接计算任意级近似的传播常数及模场分布,且可推广到二维波导的计算。  相似文献   
8.
In this paper, we give precise formulas for the general two-dimensional recursion sequences by generating function method, and make use of the multivariate generating functions asymptotic estimation technique to compute their asymptotic values.  相似文献   
9.
A connection between Romanovski polynomials and those polynomials that solve the one-dimensional Schrödinger equation with the trigonometric Rosen-Morse and hyperbolic Scarf potential is established. The map is constructed by reworking the Rodrigues formula in an elementary and natural way. The generating function is summed in closed form from which recursion relations and addition theorems follow. Relations to some classical polynomials are also given.  相似文献   
10.
We present explicit recursion relations for the four-point superconformal block functions that are essentially particular contributions of the given conformal class to the four-point correlation function. The approach is based on the analytic properties of the superconformal blocks as functions of the conformal dimensions and the central charge of the superconformal algebra. We compare the results with the explicit analytic expressions obtained for special parameter values corresponding to the truncated operator product expansion. These recursion relations are an efficient tool for numerically studying the four-point correlation function in superconformal field theory in the framework of the bootstrap approach, similar to that in the case of the purely conformal symmetry. __________ Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 152, No. 3, pp. 476–487, September, 2007.  相似文献   
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