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131.
This paper analyzes the high bit-rate optical pulse trasmission in single mode optical fiber with chromatic dispersion, polarization mode dispersion (small random birefringence) and nonlinearity. Numerical method employed can precisely describe their interactive effect on transmission performance. Different dispersion maps and the related performance are analysed. Various simulation results and discussion are given. The results show that chromatic dispersion compensation should be carefully designed. Appropriate dispersion management can also alleviate the effect of polarization mode dispersion. 相似文献
132.
Vijay Janyani Ana Vukovic John D. Paul Phillip Sewell Trevor M. Benson 《Optical and Quantum Electronics》2005,37(1-3):3-24
The paper investigates and compares a range of different models currently used for modelling nonlinear optical phenomena. The models are implemented in the numerical time domain Transmission Line Modelling (TLM) method and include a Kerr model and different formulations of the Duffing model. The models are used to simulate an all-optical limiter for a CW input and results compared with ones available in the literature. This enables a comparison to be made between the different models, from which it is concluded that the Duffing model has some advantages, when modelling materials and phenomena involving more than one frequency, arising from its ability to describe dispersive effects. These conclusions are further supported by the simulation results obtained for a pulse input. 相似文献
133.
Sugata Gangopadhyay 《Discrete Mathematics》2006,306(14):1540-1556
In 1983, Patterson and Wiedemann constructed Boolean functions on n=15 input variables having nonlinearity strictly greater than 2n-1-2(n-1)/2. Construction of Boolean functions on odd number of variables with such high nonlinearity was not known earlier and also till date no other construction method of such functions are known. We note that the Patterson-Wiedemann construction can be understood in terms of interleaved sequences as introduced by Gong in 1995 and subsequently these functions can be described as repetitions of a particular binary string. As example we elaborate the cases for n=15,21. Under this framework, we map the problem of finding Patterson-Wiedemann functions into a problem of solving a system of linear inequalities over the set of integers and provide proper reasoning about the choice of the orbits. This, in turn, reduces the search space. Similar analysis also reduces the complexity of calculating autocorrelation and generalized nonlinearity for such functions. In an attempt to understand the above construction from the group theoretic view point, we characterize the group of all GF(2)-linear transformations of GF(2ab) which acts on PG(2,2a). 相似文献
134.
本文根据谐波平衡法假设周期解的基本思想,提出了一种分析非线性振动特性的正交函数法。将位移展开为谐波的级数形式,根据线性模态和三角级数的正交性导出了一组形式简单的特征方程。有效地解决了平方非线性系统存在漂移项的困难,算例表明:本文方法精度高,收敛快,工作量小。 相似文献
135.
刘衍胜 《数学物理学报(A辑)》2005,25(3):307-314
过构造特殊的锥, 利用有界正线性算子的谱理论及不动点指数理论, 研究了奇异半正边值问题正解的存在性, 改进和推广了有关文献中的结果 相似文献
136.
The optical nonlinearity of low-dimension structures is studied in the self-effect case at a wavelength of 630 nm in a range of light intensities below 0.1 W/cm2 by waveguide methods. Common tendencies in relationships between intensity of light and optical properties of multilayer structures and semiconductor-doped glass films are detected. It is shown that the state of interfaces determines the character of optical nonlinearity. 相似文献
137.
A method and an algorithm for determining the effective deformational properties of dispersely strengthened materials with a physically nonlinear matrix and quasi-spheroidal linearly elastic inclusions are elaborated based on the stochastic differential equations of the physically nonlinear theory of elasticity. Their transformation to integral equations and the application of the method of conditional moments reduce the problem to a system of nonlinear algebraic equations, whose solution is constructed by the iteration method. The deformation diagrams as functions of the volume content of inclusions are investigated. 相似文献
138.
在北京正负电子对撞机的J/ψ和Ds能区,选择了辐射巴巴事例,并以此来研究北京谱仪的桶部簇射计数器能量响应特性.在消除了由于电子和辐射光子在桶部簇射计数器中沉积能量区域重叠的影响后,正确地得到了桶部簇射计数器在电子和光子动量小于2GeV以下的能量响应,表明在所研究能区,桶部簇射计数器的能量响应线性很好.对桶部簇射计数器微小的非线性进行修正后,重建的π0不变质量谱得到改善. 相似文献
139.
Soichiro Katayama 《Journal of Differential Equations》2005,209(1):140-171
We consider the Cauchy problem for systems of nonlinear wave equations with different propagation speeds in three space dimensions. We prove global existence of small amplitude solutions for systems with some nonresonant nonlinearities which may depend on both of the unknowns and their derivatives. Our method here can be also adopted to treat the null forms. 相似文献
140.
We report on the 320 Gb/s (40 Gb/s × 8 channels) WDM transmission experiment using short-period dispersion-managed fiber. After 320-km transmission, the average Q-factor was measured to be better than 20.4 dB. In addition, we compared the performances of various types of fibers in 40-Gb/s based systems. The results show that the SPDMF was robust to both the intra-channel and inter-channel nonlinearities due to its small average dispersion and large local dispersion. 相似文献