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排序方式: 共有584条查询结果,搜索用时 15 毫秒
51.
Siddhartha Sahi 《Annals of Combinatorics》2006,10(2):255-269
We describe a connection between discrete birth process and a certain family of multivariate interpolation polynomials. This
enables us to compute all asymptotic moments of the birth process, generalizing previously known results for the mean and
variance.
Received July 15, 2004 相似文献
52.
In our preceding work, a class of k-quantum nonlinear coherent states, i.e., the k eigenstates of the powersBk (k ≥ 3) of the annihilation operator B=-a1/f(N) of f-oscillators, are introduced. In this paper, we introduce a newkind of higher-order squeezing and an antibunching effect. The quantum statistical properties of the k states are studied.The result shows that the M-th order [M = (n 1/2)k; n = 0, 1,...] squeezing effects exist in all of the k states when kis even. There is the antibunching effect in all of the k states. 相似文献
53.
本文基于Reddy高阶剪切变形板理论导出Karman型非线性大挠度方程并用于层合板热后屈曲分析.分析中计及板初始几何缺陷和热效应.给出了四边简支.对称正交铺设层合板在均匀或非均匀抛物型热分布作用下的后屈曲分析.采用摄动-Galerkin混合法确定板的热屈曲载荷与热后屈曲平衡路径.同时讨论了横向剪切变形,板长宽比,铺层数以及初始几何缺陷等各种参数变化的影响. 相似文献
54.
本文推广了R.W.Thatcher[4]的结果,给出局部质量守恒的P3-P2元,并对矩形网格的高阶Qn-Qn-1进行了讨论. 相似文献
55.
Nail H. Ibragimov 《Journal of Mathematical Analysis and Applications》2006,318(2):742-757
Integrating factors and adjoint equations are determined for linear and non-linear differential equations of an arbitrary order. The new concept of an adjoint equation is used for construction of a Lagrangian for an arbitrary differential equation and for any system of differential equations where the number of equations is equal to the number of dependent variables. The method is illustrated by considering several equations traditionally regarded as equations without Lagrangians. Noether's theorem is applied to the Maxwell equations. 相似文献
56.
57.
HAN Zhao-Xiu 《理论物理通讯》2007,47(1):10-14
The coupled higher-order nonlinear Schroedinger system is a major subject in nonlinear optics as one of the nonlinear partial differential equation which describes the propagation of optical pulses in optic fibers. By using coupled amplitude-phase formulation, a series of new exact cnoidal and solitary wave solutions with different parameters are obtained, which may have potential application in optical communication. 相似文献
58.
Masafumi Akahira 《Annals of the Institute of Statistical Mathematics》1996,48(2):365-380
Under suitable regularity conditions, it is shown that a third order asymptotically efficient estimator is fourth order asymptotically efficient in some class of estimators in the sense that the estimator has the most concentration probability in any symmetric interval around the true parameter up to the fourth order in the class. This is a resolution of the conjecture by Ghosh (1994, Higher Order Asymptotics, Institute of Mathematical Statistics, Hayward, California). It is also shown that the bias-adjusted maximum likelihood estimator is fourth order asymptotically efficient in the class. 相似文献
59.
Activity coefficients for CHl in the system HCl+NiCl
2
+H
2
O at 298.15°K at constant total ionic strengths of 0.1, 0.5, 1.0, 2.0, and 3.0 moles-kg
–1
have been determined by an emf method. A comparison was made between Scatchard's and Pitzer's interpretations of mixed-electrolyte solutions for this system and six related systems. Preference can be given to Pitzer's method provided cognizance is taken of the effects of higher-order electrostatic terms beyond the Debye-Hückel approximation on the thermodynamic properties of asymmetrical mixtures. 相似文献
60.
Analytic solutions of the partial differential equations are needed to explain many phenomena seen in thermodynamics, aerodynamics, plasma physics, and other fields. In this paper, variational principle is analyzed of the integrable nonlinear Korteweg–de Vries (KdV) typed equation. In addition, exact solutions of this equation are obtained by using various methods such as direct integration, homogeneous balance method, Exp-function method, and Kudryashov method. 相似文献