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91.
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93.
M. Sajid 《Numerical Methods for Partial Differential Equations》2010,26(1):221-228
This article investigates the analytic solution for the flow of a third grade fluid past an infinite porous plate. The method of parameter differentiation is used to linearized the governing flow equation. The solution of the obtained linear equation is developed by differential transform method in combination with the method of superposition. The obtained results are compared with existing results in the literature and an excellent agreement is found. This shows that the parameter differentiation is a powerful technique for solving nonlinear problems. © 2009 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2010 相似文献
94.
In this paper we consider iteration of single-plateau functions, an important class of continuous functions with infinitely many forts, and investigate changes of number and length of plateaux under iteration.We use the indices flatness, plateau limit and limit length to formulate those changes. Furthermore, we compute the flatness, plateau limit and limit length for all the nine types of single-plateau functions. 相似文献
95.
α–Fe2O3/TiO2 Composite powders have been prepared by high energy ball-milling for different times. The composites were studied using Mössbauer Spectroscopy (MS) and X-ray diffraction (XRD). The patterns of XRD show broadening in the diffraction peaks, indicating a decrease in the particle size of the composites with milling time. Also, the XRD patterns show an evolving new structural phase correlated with an evolving Titanium ferrite species with milling time. Mössbauer Spectroscopy shows the evolving titanium ferrite species characterized by a quadrupole doublet at the expense of the α–Fe2O3 represented by the magnetic sextet. The doublet corresponding to the Ti-ferrite phase dominates the Mössbauer spectra at long milling time (greater than 100 h of milling). 相似文献
96.
Sean D. Brooks M. F. Mahmood J. A. Donaldson 《Journal of Mathematical Modelling and Algorithms》2004,3(1):19-29
A numerical investigation, based on the split-step Fourier transform algorithm of all optical switching of solitons in a low
birefringent optical fiber is presented. The numerical algorithm is described in detail.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
97.
In this paper, we consider the problem of making inferences on the common mean of several normal populations when sample sizes and population variances are possibly unequal. We are mainly concerned with testing hypothesis and constructing confidence interval for the common normal mean. Several researchers have considered this problem and many methods have been proposed based on the asymptotic or approximation results, generalized inferences, and exact pivotal methods. In addition, Chang and Pal (Comput Stat Data Anal 53:321–333, 2008) proposed a parametric bootstrap (PB) approach for this problem based on the maximum likelihood estimators. We also propose a PB approach for making inferences on the common normal mean under heteroscedasticity. The advantages of our method are: (i) it is much simpler than the PB test proposed by Chang and Pal (Comput Stat Data Anal 53:321–333, 2008) since our test statistic is not based on the maximum likelihood estimators which do not have explicit forms, (ii) inverting the acceptance region of test yields a genuine confidence interval in contrast to some exact methods such as the Fisher’s method, (iii) it works well in terms of controlling the Type I error rate for small sample sizes and the large number of populations in contrast to Chang and Pal (Comput Stat Data Anal 53:321–333, 2008) method, (iv) finally, it has higher power than recommended methods such as the Fisher’s exact method. 相似文献
98.
The problem of the mixed convection boundary-layer flow past an isothermal vertical circular cylinder is considered in both the cases when the buoyancy forces aid and oppose the development of the boundary layer. A series solution is obtained, valid near the leading edge, and this is extended by a numerical solution of the full equations, which in the aiding case, becomes inaccurate downstream. An approximate solution is also derived which gives a good estimate for the heat transfer near the leading edge and has the correct asymptotic form well downstream. In the opposing case, the boundary layer is seen to separate at a finite distance downstream, with, for moderate values of the buoyancy parameter, the numerical solution indicating a regular behaviour near separation. 相似文献
99.
M. F. Mahmood 《Mathematical and Computer Modelling》2002,36(11-13)
Using a variational method, a new model of the nonlinear propagation of optical solitons generated from semiconductor lasers through lossy elliptically low birefringent fiber, is presented within the framework of a system of coupled nonlinear Schroedinger (CNLS) equations with oscillating terms. This analytic model demonstrates polarized soliton oscillations in a lossy elliptically low birefringent optical fiber. 相似文献
100.
Mahdokht Kalantari Masoud Rabbani Mahmood Ebadian 《Applied Mathematical Modelling》2011,35(3):1363-1377
In this paper, we present a novel decision support system for order acceptance/rejection in a hybrid Make-to-Stock/Make-to-Order production environment. The proposed decision support system is comprised of five steps. At the first step, the customers are prioritized based on a fuzzy TOPSIS method. Rough-cut capacity and rough-cut inventory are calculated in the second step and in case of unavailability in capacity and materials, some undesirable orders are rejected. Also, proper decisions are made about non-rejected orders. At the next step, prices and delivery dates of the non-rejected orders are determined by running a mixed-integer mathematical programming model. At the fourth step, a set of guidelines are proposed to help the organization negotiate over price and due date with the customers. In the next step, if the customer accepts the offered price and delivery date, the order is accepted and later considered in the production schedule of the shop floor, otherwise the order is rejected. Finally, numerical experiments are conducted to show the tractability of the applied mathematical programming model. 相似文献