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525602:Advanced Numerical Methods for ME
School of Mechanical Engineering
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Prescribed text : Numerical Method for Engineering, Seventh Edition, Steven C.Chapra, Raymond P. Canale.,McGraw Hill 2014
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Recommended reading : Numerical Methods for Engineers and Scientists, Amos Gilat and Vish Subramaniam, Wiley,2008 Numerical Methods Using MATLAB, John.H.Methews., Kurtis D.Fink.,Prentice Hall , Fourth Edition,2004 ระเบียบวิธีเชิงตัวเลขในงานวิศวกรรม, ปราโมทย์ เดชะอำไพ., สำนักพิมพ์แห่งจุฬาลงกรณ์มหาวิทยาลัย พ.ศ.2556
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Course Description Truncation errors and the Taylor series
Numerical Solutions for ODEs Numerical Solutions for PDEs Finite difference method Optimization
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Errors in Numerical Solutions
Truncation Errors Round-Off Errors Total Error Local Error Global Error
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Truncation Errors :The Taylor series
Zero-order approximation First-order approximation
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The Taylor series approximation
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The Remainder for the Taylor Series Expansion
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Truncation Errors: Example
Taylor’s series expansion: The exact value: The Zero-order approximation; The truncation error:
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Truncation Errors: Example
Taylor’s series expansion: The exact value: The first-order approximation; The truncation error:
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Round-Off Errors
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Total Error The true error: The true relative error:
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Total Error The Global Error is the total discrepancy due to past as well as present steps The Local Error refers to the error incurred over a single step. It is calculated with a Taylor series expansion.
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The Global Error The relative global error:
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The Total Error: Example
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The Total Error: Example
The percent relative global error (Step 1); The percent relative global error (Step 2);
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The Total Error: Example
Exact estimates of the errors in Euler’s method Problem statement:
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The Total Error: Example
The percent relative local error (Step 1);
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The Total Error: Example
The percent relative local error (Step 2);
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Numerical Solutions for ODEs
Introduction to Ordinary Differential Equations (ODE)
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Study Objectives Solve Ordinary differential equation (ODE) problems.
Appreciate the importance of numerical method in solving ODE. Assess the reliability of the different techniques. Select the appropriate method for any particular problem.
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Computer Objectives Develop programs to solve ODE.
Use software packages to find the solution of ODE
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Learning Objectives of Lesson 1
Recall basic definitions of ODE, order, linearity initial conditions, solution, Classify ODE based on( order, linearity, conditions) Classify the solution methods
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Derivatives Derivatives Partial Derivatives Ordinary Derivatives
v is a function of one independent variable Partial Derivatives u is a function of more than one independent variable
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Differential Equations
Ordinary Differential Equations involve one or more Ordinary derivatives of unknown functions Partial Differential Equations involve one or more partial derivatives of unknown functions
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Ordinary Differential Equations
Ordinary Differential Equations (ODE) involve one or more ordinary derivatives of unknown functions with respect to one independent variable x(t): unknown function t: independent variable
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Order of a differential equation
The order of an ordinary differential equations is the order of the highest order derivative First order ODE Second order ODE Second order ODE
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Solution of a differential equation
A solution to a differential equation is a function that satisfies the equation.
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Linear ODE Linear ODE Non-linear ODE An ODE is linear if
The unknown function and its derivatives appear to power one No product of the unknown function and/or its derivatives Linear ODE Non-linear ODE
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Nonlinear ODE An ODE is linear if
The unknown function and its derivatives appear to power one No product of the unknown function and/or its derivatives
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Uniqueness of a solution
In order to uniquely specify a solution to an n th order differential equation we need n conditions Second order ODE Two conditions are needed to uniquely specify the solution
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Auxiliary conditions auxiliary conditions Boundary Conditions
The conditions are not at one point of the independent variable Initial Conditions all conditions are at one point of the independent variable
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Boundary-Value and Initial value Problems
Boundary-Value Problems The auxiliary conditions are not at one point of the independent variable More difficult to solve than initial value problem Initial-Value Problems The auxiliary conditions are at one point of the independent variable same different
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Classification of ODE ODE can be classified in different ways Order
First order ODE Second order ODE Nth order ODE Linearity Linear ODE Nonlinear ODE Auxiliary conditions Initial value problems Boundary value problems
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Analytical Solutions Analytical Solutions to ODE are available for linear ODE and special classes of nonlinear differential equations.
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Numerical Solutions Numerical method are used to obtain a graph or a table of the unknown function Most of the Numerical methods used to solve ODE are based directly (or indirectly) on truncated Taylor series expansion
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Classification of the Methods
Numerical Methods for solving ODE Single-Step Methods Estimates of the solution at a particular step are entirely based on information on the previous step Multiple-Step Methods Estimates of the solution at a particular step are based on information on more than one step
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More Lessons in this unit
Taylor series methods Midpoint and Heun’s method Runge-Kutta methods Multiple step Methods Solving systems of ODE Boundary value Problems
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The Taylor series Zero-order approximation First-order approximation
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The Taylor series approximation
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The Remainder for the Taylor Series Expansion
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The sequence of events in the application of ODEs for engineering problem solving
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Differential equations
Analytical methods Exact solution Numerical methods Approximate solution
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