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111.
?smail Aslan 《Applied mathematics and computation》2010,217(2):937-4217
We report an observation on two recent analytic methods; the (G′/G)-expansion method and the simplest equation method. 相似文献
112.
?smail Aslan 《Journal of Computational and Applied Mathematics》2010,234(12):3213-1710
Assas [Laila M.B. Assas, New exact solutions for the Kawahara equation using Exp-function method, J. Comput. Appl. Math. 233 (2009) 97-102] found some supposedly new exact solutions to the Kawahara equation by means of the Exp-function method. Unfortunately, they are incorrect. We emphasize that the article contains erroneous formulas and resulting relations. In fact, no numerical method was used. 相似文献
113.
In this study, linear and nonlinear partial differential equations with the nonhomogeneous initial conditions are considered. We used Variational iteration method (VIM) and Homotopy perturbation method (HPM) for solving these equations. Both methods are used to obtain analytic solutions for different types of differential equations. Four examples are presented to show the application of the present techniques. In these schemes, the solution takes the form of a convergent series with easily computable components. The present methods perform extremely well in terms of efficiency and simplicity. © 2009 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 2010 相似文献
114.
İbrahi̇m Çanak 《Applied Mathematics Letters》2010,23(7):818-820
In this work we give an alternative proof of the generalized Littlewood Tauberian theorem for the Abel summability method using a corollary to Karamata’s Main Theorem [J. Karamata, Über die Hardy–Littlewoodschen Umkehrungen des Abelschen Stetigkeitssatzes, Math. Z. 32 (1930) 319–320]. 相似文献
115.
116.
We propose a new globalization strategy that can be used in unconstrained optimization algorithms to support rapid convergence from remote starting points. Our approach is based on using multiple points at each iteration to build a sequence of representative models of the objective function. Using the new information gathered from those multiple points, a local step is gradually improved by updating its direction as well as its length. We give a global convergence result and also provide the parallel implementation details accompanied with a numerical study. Our numerical study shows that the proposed algorithm is a promising alternative as a globalization strategy. 相似文献
117.
R?za Bayrak Mahmut Durmu? ?smail De?irmencio?lu 《Journal of organometallic chemistry》2011,696(23):3807-3815
The synthesis and characterization of new peripherally tetra-3,5-dimethylpyrazole-1-methoxy substituted metal-free (4), zinc (5), nickel (6), cobalt (7), copper (8) and lead (9) phthalocyanines are described for the first time in this study. The photophysical (fluorescence quantum yields and fluorescence lifetimes) and photochemical (photodegradation and singlet oxygen quantum yields) properties of metal-free (4), zinc (5) and lead (9) phthalocyanines are studied in dimethylsulfoxide (DMSO). Nickel (6), cobalt (7) and copper (8) phthalocyanines (6-8) did not evaluate for this purpose due to transition metal and paramagnetic behavior of central metals in the phthalocyanine cavity. The fluorescence quenching behavior of metal-free (4), zinc (5) and lead (9) phthalocyanines are also investigated. The fluorescence emissions of these phthalocyanines are effectively quenched by 1,4-benzoquinone in DMSO. 相似文献
118.
In this paper, we consider the equation x 2?L n x y+(?1) n y 2 = ±5 r and determine the values of n for which the equation has positive integer solutions x and y. Moreover, we give all positive integer solutions of the equation x 2?L n x y+(?1) n y 2 = ±5 r when the equation has positive integer solutions. 相似文献
119.
İdris Dağ Ali Şahin Alper Korkmaz 《Numerical Methods for Partial Differential Equations》2010,26(6):1483-1503
The Galerkin method is used with quadratic B‐spline base functions to obtain the numerical solutions of Fisher's equation which is a one dimensional reaction‐diffusion equation. To observe the effects of reaction and diffusion, four test problems related to pulse disturbance, step disturbance, super‐speed wave and strong reaction are studied. A comparison is performed between the obtained numerical results and some earlier studies. © 2009 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2010 相似文献
120.
Journal of Thermal Analysis and Calorimetry - The molar heat capacity parameters of CdNb2O6 and CdTa2O6 oxides, which attracted attention for their promising catalytic and optical properties, were... 相似文献