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61.
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
62.
63.
加速牛顿迭代收敛的新方法 总被引:2,自引:0,他引:2
提出了加速牛顿迭代收敛的新思想,构造出一类加权牛顿迭代格式,通过选取最优加权因子,使得该格式具有高阶收敛性和较小的渐近误差常数。 相似文献
64.
We consider the dynamics of the lowest order transversal vibration mode of a suspension bridge, for which the hangers are treated as one-sided springs, according to the model of Lazer and McKeena [SIAM Review
58, 1990, 537]. We analyze in particular the multi-stability of periodic attractors and the basin of attraction structure in phase space and its dependence with the model parameters. The parameter values used in numerical simulations have been estimated from a number of bridges built in the United States and in the United Kingdom, thus taking into account realistic, yet sometimes simplified, structural, aerodynamical, and physical considerations. 相似文献
65.
总结两个保守映象不可逆地分段连续链接(称为类耗散系统)以及一个保守映象与一个耗散映象不可逆地分段连续链接(称为半耗散系统)情况下得到的五项共同动力学特征:不连续边界象集构成的随机网成为唯一的混沌轨道;由于某些相点具有两个逆象而导致的相空间塌缩(类耗散);由于系统的不连续不可逆性质而出现的胖分形禁区网;在具有吸引子共存时占据不连续边界象集随机网和胖分形禁区网区域的点滴状吸引域以及由此导致的吸引子不可预言性;即使在传统强耗散存在的情况下点滴状吸引域仍由类耗散机制主宰.以一个累积-触发电路为例,说明这五项系统动
关键词:
随机网
禁区网
点滴状吸引域 相似文献
66.
含高阶非线性效应的薛定谔方程的精确解研究 总被引:1,自引:0,他引:1
利用孤子理论,研究了含三次和五次非线性项的非线性薛定谔方程,在参数取不同值时得到了方程的新型亮孤子解、新型暗孤子解和新的三角函数周期解。 相似文献
67.
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
68.
69.
Coronene tatracarboxylate CTC and octacarboxylate COC have been utilized to interact with dipyridinium DP and tetrapyridinium TP to assemble new supramolecular polymers in water. It was revealed that CTC interacted with DP and TP in 1:2 and 1:1 stoichiometry, whereas the binding between COC and DP and TP occurred in 1:4 and 1:2 stoichiometry. For all complexations, DP and TP behaved as a uni- or siamesed tweezers to clamp CTC or COC driven by ion-pair attraction and hydrophobically driven stacking of the pyridinium and coronene units. Apparent association constants were determined to be 33400 (CTC/DP), 9400 (COC/DP), 151000 (CTC/TP), and 89000 (COC/TP) M?1, respectively, for the single clamping binding motif of the four complexes. Dynamic light scattering and isothermal titration calorimetric experiments supported that the mixtures of CTC and COC with TP formed linear and cross-linked supramolecular polymers. 相似文献
70.
ABSTRACTAnalytical solution of the first-order Ornstein–Zernike equation known as the first-order mean spherical approximation (FMSA) theory due to Tang and Lu [J. Chem. Phys. 99, 9828 (1993)] is used to write down a closed equation for the static structure factor of the hard-sphere fluid with a short-range Yukawa attraction. Calculations are performed for a Yukawa decay exponent that corresponds to a range of attraction that does not exceed the first coordination shell of Lennard-Jones-like simple fluids. By comparison with Monte Carlo simulation data it is shown that the analytical FMSA equation for the static structure factor is of the same or even of superior accuracy as that within the seminumerical mean spherical approximation theory. 相似文献