Geri Dön

Homotopy-based methods for fractional differential equations

Başlık çevirisi mevcut değil.

  1. Tez No: 403363
  2. Yazar: İNAN ATEŞ
  3. Danışmanlar: Dr. PAUL ZEGELING
  4. Tez Türü: Doktora
  5. Konular: Matematik, Mathematics
  6. Anahtar Kelimeler: Belirtilmemiş.
  7. Yıl: 2017
  8. Dil: İngilizce
  9. Üniversite: Universiteit Utrecht
  10. Enstitü: Yurtdışı Enstitü
  11. Ana Bilim Dalı: Belirtilmemiş.
  12. Bilim Dalı: Belirtilmemiş.
  13. Sayfa Sayısı: 99

Özet

Özet yok.

Özet (Çeviri)

This thesis discusses numerical methods for models with fractional order derivatives. These methods make use of infinite series, which are based on the notion of homotopy with an additional method parameter to accelerate the convergence properties. In Chapter 1, we start with a brief motivation and history of fractional calculus. Next, we introduce the Gamma function and the Mittag-Leffler function, which play an important role in the theory of fractional derivatives. There exist many definitions of fractional order derivatives. Among the most important ones, we present four definitions: the Riesz, the Riemann-Liouville, the Caputo, and the Grünwald-Letnikov derivative. Properties, relations and differences between these are mentioned to show the different aspects and consequences. Furthermore, the importance of fractional calculus is emphasized and the background for using fractional differential equations is briefly described. The widespread application of fractional order derivatives is discussed and a series of fractional order models from many different application areas is given. At the end of chapter 1, an outline of the new contribution to this area is shortly indicated. In Chapter 2, we focus on a fractional order advection-diffusion-reaction model. We introduce the homotopy perturbation method to solve the model. First, we analyze the convergence of the method and compare it with the Adomian decomposition method to understand its effectivity for different models. Some theoretical results are given and are explained in terms of convergence tables and graphics. Numerical experiments illustrate the performance of this method, when applied to a test set of boundary-value problems. Both convergent and divergent numerical solutions are presented. In Chapter 3, we deal with traveling wave solutions in time-fractional partial differential equations. This is done by using the homotopy analysis method which is an extension of the homotopy perturbation method. Primarily, we explain the importance of the convergence parameter ~ in the so-called ~-curve. This curve enables us, somehow, to control the convergence region of the method. Especially, for this curve, the role of an optimal ~ value is emphasized. Numerical results for a special partial differential equation are given: the time-fractional Fisher equation. The effect of changing the fractional order on the solution behavior is shown. In Chapter 4, we study Padé approximations to improve the numerical solutions which were obtained by the homotopy analysis method in the previous chapter. A Padé approximation has the potential to produce more accurate numerical solutions not only for higher time values in the differential equation, but also speeds up the computation time of the series. First, we introduce the rational homotopy perturbation method which makes use of a Padé approximation for stationary problems. For example, it is applied to a convective-radiative equation and to Troesch'smodel. Finally, we apply a Padé approximation with the homotopy analysis method to a timefractional Fisher partial differential equation and show its usefulness in several experiments

Benzer Tezler

  1. Üçüncü mertebeden kesirli kısmi diferansiyel denklemlerin tam ve yaklaşık çözümleri

    Exact and numerical solutions of third order fractional partial differential equations

    CEREN BAKIR

    Yüksek Lisans

    Türkçe

    Türkçe

    2020

    MatematikHarran Üniversitesi

    Matematik Ana Bilim Dalı

    DR. ÖĞR. ÜYESİ MAHMUT MODANLI

  2. Diferansiyel denklemlerin bazı yaklaşık çözüm yöntemleriyle çözümü ve karşılaştırılması

    Solution and comparison of differential equations with some approximate solutions methods

    ORHAN YÜKSEL

    Yüksek Lisans

    Türkçe

    Türkçe

    2024

    MatematikSakarya Üniversitesi

    Matematik Ana Bilim Dalı

    PROF. DR. ÖMER FARUK GÖZÜKIZIL

  3. Klasik ve kesirli yaklaşım temelinde etkileşimli bozon gazlarının bose-einstein yoğuşması ve dinamiğinin incelenmesi

    Investigation of the bose-Einstein condensation and dynamics of ınteracting bose gases based on classical and fractional approach

    NESLİHAN ÜZAR

    Doktora

    Türkçe

    Türkçe

    2012

    Fizik ve Fizik Mühendisliğiİstanbul Üniversitesi

    Fizik Ana Bilim Dalı

    DOÇ. DR. EKREM AYDINER

  4. Approximate methods for complex nonlinear dynamical systems

    Karmaşık değerli dinamik sistemler için yaklaşık yöntemler

    SÜMEYRA ZOR

    Yüksek Lisans

    İngilizce

    İngilizce

    2014

    MatematikDokuz Eylül Üniversitesi

    Matematik Ana Bilim Dalı

    PROF. DR. GONCA ONARGAN

  5. Taylor serlerine dayanan yaklaşık yöntemler üzerine bir çalışma

    A study on approximation methods based on Taylor series

    EDA YÜLÜKLÜ

    Doktora

    Türkçe

    Türkçe

    2009

    MatematikEge Üniversitesi

    Matematik Ana Bilim Dalı

    PROF. DR. TURGUT ÖZİŞ