Geometric programming: Difference between revisions

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== Numerical Examples ==
== Numerical Examples ==


=== To solve a standard form Geometric Programming problem ===
=== Solve a Geometric Programming problem in standard form ===
'''Minimize''' <math>f_0(x,y) = x^2y^3 + 3x + 2xy </math>
'''Minimize''' <math>f_0(x,y) = x^2y^3 + 3x + 2xy </math>


'''Subject to:''' <math>f_i(x)\leqslant1 </math>,    <math>i </math> = 1,...,m,
'''Subject to:''' <math>x^5+2y^6+1\leqslant1 </math>,


<math>g_i(x) = 1 </math>,    <math>i </math> = 1,...,p,
<math>x+2y\leqslant1 </math>,


<math>x_i > 0 </math>,   <math>i </math> = 1,...,q,
<math>xy = 1 </math>,
 
<math>x > 0 </math>,  
 
<math>y > 0 </math>  
 
For the problem above, this is a geometric optimization problem in standard form.
 
The solution is: ...
 
=== Transform Nonconvex Optimization Problems to Convex Optimization problem ===
'''Reformulate the following non-convex MINLP to a convex one'''
 
'''Minimize''' <math>f_0(x_1,x_2,x_3) = 16(x_1)^2(x_2)^2 + 3(x_2)^3(x_3)^4 - \left ( \frac{16}{x_2} \right ) </math>
 
'''Subject to:''' <math>x^5+2y^6+1\leqslant1 </math>,
 
<math>x+2y\leqslant1 </math>,
 
<math>xy = 1 </math>,
 
<math>x > 0 </math>,
 
<math>y > 0 </math>





Revision as of 16:04, 13 November 2021

Authors: Wenjun Zhu(wz274), Sam Olsen(sgo23) (SYSEN5800, FALL 2021)

Introduction

Theory/Methodology

Definition

The standard form of Geometric Programming optimization is to minimize the objective function which must be posynomial. The inequality constraints can only have the form of a posynomial less than or equal to one, and the equality constraints can only have the form of a monomial equal to one.

Standard Form

Minimize

Subject to: , = 1,...,m,

Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle g_i(x) = 1 } , Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle i } = 1,...,p,

Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle x_i > 0 } , Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle i } = 1,...,q,

where Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle f_i(x)} are posynomial functions, Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle g_i(x)} are monomials, and Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle x_i } are the optimization variables.



Numerical Examples

Solve a Geometric Programming problem in standard form

Minimize Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle f_0(x,y) = x^2y^3 + 3x + 2xy }

Subject to: Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle x^5+2y^6+1\leqslant1 } ,

Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle x+2y\leqslant1 } ,

Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle xy = 1 } ,

Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle x > 0 } ,

Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle y > 0 }

For the problem above, this is a geometric optimization problem in standard form.

The solution is: ...

Transform Nonconvex Optimization Problems to Convex Optimization problem

Reformulate the following non-convex MINLP to a convex one

Minimize Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle f_0(x_1,x_2,x_3) = 16(x_1)^2(x_2)^2 + 3(x_2)^3(x_3)^4 - \left ( \frac{16}{x_2} \right ) }

Subject to: Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle x^5+2y^6+1\leqslant1 } ,

Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle x+2y\leqslant1 } ,

Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle xy = 1 } ,

Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle x > 0 } ,

Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle y > 0 }



Applications

Conclusion

References