modern research physics

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در این مقاله یک روش عددی مناسب برای حل معادلات انتگرال- دیفرانسیل فردهلم غیر خطی با تأخیر زمانی ارائه شده است. روش مبتنی بر بسط تیلور می باشد. این روش معادله انتگرال- دیفرانسیل و شرایط داده شده را به معادله ماتریسی که متناظر با یک دستگاه از معادلات جبری غیر خطی با ضرایب مجهول بسط تیلور می باشد تبدیل می کند، که از حل دستگاه، ضرایب بسط تیلور تابع جواب به دست می آید. سپس با مثال هایی کارایی روش را ارزیابی می کنیم.

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In this article‎, ‎the efficient numerical methods for finding solution of the linear and nonlinear Fredholm integral equations of the second kind on base of Bernstein multi scaling functions are being presented‎. ‎In the beginning the properties of these functions‎, ‎which are a combination of block-pulse functions on ‎, ‎and Bernstein polynomials with the dual operational matrix are presented‎. ‎Then these properties are used for the purpose of conversion of the mentioned integral equation to a matrix equation that are compatible to a algebraic equations system‎. ‎The imperative of the Bernstein multi scaling functions are‎, ‎for the proper quantitative value of and have a high accuracy and specifically the relative errors of the numerical solutions will be minimum‎. ‎The presented methods from the standpoint of computation are very simple and attractive and the numerical examples which were presented at the end shows the efficiency and accuracy of these methods‎.

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In this paper, a collocation method based on the Bessel polynomials is used for the solution of nonlinear Fredholm-Volterra-Hammerstein integro-differential equations (FVHIDEs) under mixed condition. This method of estimating the solution, transforms the nonlinear (FVHIDEs) to matrix equations with the help of Bessel polynomials of the first kind and collocation points. The matrix equations correspond to a system of nonlinear algebraic equations with the unknown Bessel coefficients. Present results and comparisons demonstrate that our estimate has good degree of accuracy and this method is more valid and useful than other methods.In this paper, a collocation method based on the Bessel polynomials is used for the solution of nonlinear Fredholm-Volterra-Hammerstein integro-differential equations (FVHIDEs) under mixed condition. This method of estimating the solution, transforms the nonlinear (FVHIDEs) to matrix equations with the help of Bessel polynomials of the first kind and collocation points. The matrix equations correspond to a system of nonlinear algebraic equations with the unknown Bessel coefficients. Present results and comparisons demonstrate that our estimate has good degree of accuracy and this method is more valid and useful than other methods.

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In this paper rationalized Haar (RH) functions method is applied to approximate the numerical solution of the fractional Volterra integro-differential equations (FVIDEs). The fractional derivatives are described in Caputo sense. The properties of RH functions are presented, and the operational matrix of the fractional integration together with the product operational matrix are used to reduce the computation of FVIDEs into a system of algebraic equations. By using this technique for solving FVIDEs time and computational are small. Numerical examples are given to demonstrate application of the presented method with RH functions base.In this paper rationalized Haar (RH) functions method is applied to approximate the numerical solution of the fractional Volterra integro-differential equations (FVIDEs). The fractional derivatives are described in Caputo sense. The properties of RH functions are presented, and the operational matrix of the fractional integration together with the product operational matrix are used to reduce the computation of FVIDEs into a system of algebraic equations. By using this technique for solving FVIDEs time and computational are small. Numerical examples are given to demonstrate application of the presented method with RH functions base.