359 research outputs found
Backstepping PDE Design: A Convex Optimization Approach
Abstract\u2014Backstepping design for boundary linear PDE is
formulated as a convex optimization problem. Some classes of
parabolic PDEs and a first-order hyperbolic PDE are studied,
with particular attention to non-strict feedback structures. Based
on the compactness of the Volterra and Fredholm-type operators
involved, their Kernels are approximated via polynomial
functions. The resulting Kernel-PDEs are optimized using Sumof-
Squares (SOS) decomposition and solved via semidefinite
programming, with sufficient precision to guarantee the stability
of the system in the L2-norm. This formulation allows optimizing
extra degrees of freedom where the Kernel-PDEs are included
as constraints. Uniqueness and invertibility of the Fredholm-type
transformation are proved for polynomial Kernels in the space
of continuous functions. The effectiveness and limitations of the
approach proposed are illustrated by numerical solutions of some
Kernel-PDEs
Solution of the Volterra-Fredholm integral equations via the Bernstein polynomials and least squares approach
We develop a numerical scheme to solve a general category of VolterraFredholm integral equations. For this purpose, the Bernstein polynomials and their features have been used. We convert the main equation into a set of algebraic equations in which the coefficient matrix is obtained by the least squares approximation approach. The error analysis is given to corroborate the precision of the proposed method. Numerical results are presented to demonstrate the success of the scheme for solving integral equations.Publisher's Versio
A new numerical technique based on Chelyshkov polynomials for solving two-dimensional stochastic It\^o-Volterra Fredholm integral equation
In this paper, a two-dimensional operational matrix method based on
Chelyshkov polynomials is implemented to numerically solve the two-dimensional
stochastic It\^o-Volterra Fredholm integral equations. These equations arise in
several problems such as an exponential population growth model with several
independent white noise sources. In this paper a new stochastic operational
matrix has been derived first time ever by using Chelyshkov polynomials. After
that, the operational matrices are used to transform the It\^o-Volterra
Fredholm integral equation into a system of linear algebraic equations by using
Newton cotes nodes as collocation point that can be easily solved. Furthermore,
the convergence and error bound of the suggested method are well established.
In order to illustrate the effectiveness, plausibility, reliability, and
applicability of the existing technique, two typical examples have been
presented
Solving Linear Volterra – Fredholm Integral Equation of the Second Type Using Linear Programming Method
في هذا البحث تم عرض تقنية جديدة لإيجاد حل لثلاثة أنواع من المعادلات التكاملية الخطية من النوع الثاني المتضمنة: معادلة فولتيرا-فريدهولم التكاملية (LVFIE) ( الحالة العامة), معادلة فولتيرا التكاملية (LVIE) و معادلة فريدهولم التكامليىة (LFIE) (كحالتين خاصتين). التقنية الجديدة تعتمد على تقريب الحل الى متعددة حدود من الدرجة (m-1) وبعد ذلك تحويل المسألة الى مسألة برمجة خطية (LPP) والتي سوف تحل لايجاد الحل التقريبي لمعادلة فولتيرا- فريدهولم التكاملية الخطية من النوع الثاني(LVFIE) . علاوة على ذلك تم استخدام الطرق التربيعية التي تضم: قاعدة شبه المنحرف (TR), قاعدة سمبسون 3/1 (SR), قاعدة بول (BR) وصيغة رومبرك للتكامل (RI) لتقريب التكامل الموجود في LVFIE , كما تم عمل مقارنات بين هذه الطرق. واخيرا لزيادة التوضيح تم اعطاء الخوارزمية المتبعة في الحل وتم تطبيقها على امثلة اختبارية لتوضيح فعالية التقنية الجديدة.In this paper, a new technique is offered for solving three types of linear integral equations of the 2nd kind including Volterra-Fredholm integral equations (LVFIE) (as a general case), Volterra integral equations (LVIE) and Fredholm integral equations (LFIE) (as special cases). The new technique depends on approximating the solution to a polynomial of degree and therefore reducing the problem to a linear programming problem(LPP), which will be solved to find the approximate solution of LVFIE. Moreover, quadrature methods including trapezoidal rule (TR), Simpson 1/3 rule (SR), Boole rule (BR), and Romberg integration formula (RI) are used to approximate the integrals that exist in LVFIE. Also, a comparison between those methods is produced. Finally, for more explanation, an algorithm is proposed and applied for testing examples to illustrate the effectiveness of the new technique
Convergence analysis and parity conservation of a new form of a quadratic explicit spline with applications to integral equations
In this study, a new form of a quadratic spline is obtained, where the coefficients are determined explicitly by variational methods. Convergence is studied and parity conservation is demonstrated. Finally, the method is applied to solve integral equations.Fil: Ferrari, Alberto José. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario; Argentina. Universidad Nacional de Rosario. Facultad de Ciencias Exactas Ingeniería y Agrimensura. Escuela de Ciencias Exactas y Naturales. Departamento de Matemática; ArgentinaFil: Lara, Luis Pedro. Universidad del Centro Educativo Latinoamericano; ArgentinaFil: Santillan Marcus, Eduardo Adrian. Universidad Nacional de Rosario. Facultad de Ciencias Exactas Ingeniería y Agrimensura. Escuela de Ciencias Exactas y Naturales. Departamento de Matemática; Argentin
A Comparative Study Between ADM and MDM for a System of Volterra Integral Equation
In this paper, a comparative study between Adomain decomposition method (ADM) and Modified decomposition method (MDM) for a system of volterra integral equation. From the illustrate examples it is observed that the exact solution is smaller in both methods, the modified decomposition method is more proficient than its traditional ones it is less complicated, needs less time to get to the solution and most importantly the exact solution is achieved in two iterations
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