Rank: 1401 based on 90 downloads (last 30 days) and 6 files submitted
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John Hedengren

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Brigham Young University

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11 Feb 2014 Screenshot Dynamic Optimization with the APMonitor Toolbox Fit a dynamic model to experimental data Author: John Hedengren orthogonal collocatio..., dynamic simulation, dynamic optimization, parameter estimation, toolbox 13 0
11 Feb 2014 Screenshot Dynamic Parameter Estimation and Confidence Intervals Tutorial video and files on solving a dynamic optimization problem Author: John Hedengren confidence interval, parameter estimation, dynamic optimization 17 1
12 Dec 2013 Screenshot Prosthetic Leg Dynamic Simulation Effect of a spring constant on travel and mechanical efficiency Author: John Hedengren prosthetic, efficiency, spring constant 13 0
11 Dec 2013 Screenshot Transient Catalytic Converter in Simulink Active Heating of During Automotive Start-up for Pollution Reduction Author: John Hedengren catalytic converter, active heating, pollution, transient reactor 16 1
  • 5.0
5.0 | 1 rating
11 Dec 2013 Screenshot Bellagio Fountain Simulation Simulation of the Bellagio Fountain (100 nozzles) Author: John Hedengren hydrodynamics, dynamic simulation, fountain, bellagio, potw, pick of the week 12 1
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07 Aug 2014 MINLP: Mixed Integer Nonlinear Programming Mixed Integer Nonlinear Programming Solver with APM MATLAB Author: John Hedengren

Below is a simple model file that demonstrates how to load in external parameters into APMonitor. You can replace the File *.csv section with loading a CSV file of your choice through MATLAB with the csv_load() function. For testing, just copy the lines below and insert into the web-interface at: http://apmonitor.com/online/view_pass.php

Constants
m = 4

Parameters
c[1:m] = 1.2

Variables
intv ! integer variables start with "int"

Intermediates
! summation of all elements
s[0] = 0
s[1:m] = s[0:m-1] + c[1:m]

Equations
! v to be equal to the nearest integer for summation
minimize (s[m] - intv)^2

File *.csv
c[1], 2.3
c[2], 5.1
c[4], 0.0
End File

07 Aug 2014 MINLP: Mixed Integer Nonlinear Programming Mixed Integer Nonlinear Programming Solver with APM MATLAB Author: John Hedengren

The easiest way is probably as a CSV file and then load the data file with the command:

csv_load (server, app, csv_filename)

You'll need the APM MATLAB toolbox library that you can download from APMonitor.com. If you have the values in MATLAB you can also declare your parameters as FVs (fixed values) to create a way to load values dynamically such as:

apm_info (server, app, 'FV', 'c[1][5][2][25]')
apm_meas (server, app, 'c[1][5][2][25]', 5.2)

Unfortunately there are only convenient ways to load in 2D matrices in APMonitor.

06 Aug 2014 MINLP: Mixed Integer Nonlinear Programming Mixed Integer Nonlinear Programming Solver with APM MATLAB Author: John Hedengren

Okkes, you may find it easier to declare a constants and then use vectors and arrays within APMonitor to define variables and/or equations. Here is an example:

Constants
n = 130
m = 75
End Constants

Variables
val[1:n][1::m]
End Variables

Equations
val[1:n/2][1::m] = val[2:n/2+1][1::m]
val[n/2:n][1::m] = 6
End Equations

Here is some additional information:

http://apmonitor.com/wiki/index.php/Main/Arrays

You can also submit a question to the APMonitor Discussion Forum here:

http://apmonitor.com/wiki/index.php/Main/UsersGroup

Let me know if you have any additional questions.

11 Feb 2014 Dynamic Parameter Estimation and Confidence Intervals Tutorial video and files on solving a dynamic optimization problem Author: John Hedengren

Here is the video tutorial that demonstrates the development of the files:

http://youtu.be/ynm7B0N0_Yw

10 Feb 2014 MINLP: Mixed Integer Nonlinear Programming Mixed Integer Nonlinear Programming Solver with APM MATLAB Author: John Hedengren

Elham,

This file shows a branch and bound algorithm in MATLAB but it is development code that is meant for understanding the algorithms. If you just have an MINLP problem that you'd like to solve, I'd recommend that you use either a program like AMPL or APMonitor. For a tutorial on solving a Mixed Integer problem, please refer to this video:

http://youtu.be/i8WS6HlE8qM

If you start at 8:30, you'll see how to set up an integer programming problem (by adding "int" to the variables names). The APOPT solver is an MINLP solver and will be able to solve your problem and it will do it much faster than this development MATLAB code.

-John

Comments and Ratings on John's Files View all
Updated File Comment by Comments Rating
11 Feb 2014 Dynamic Parameter Estimation and Confidence Intervals Tutorial video and files on solving a dynamic optimization problem Author: John Hedengren Hedengren, John

Here is the video tutorial that demonstrates the development of the files:

http://youtu.be/ynm7B0N0_Yw

03 Feb 2014 Bellagio Fountain Simulation Simulation of the Bellagio Fountain (100 nozzles) Author: John Hedengren Kocher, Michel

Dear John,
Thank's for this nice simulation

I have som problems understanding the mathematical model you use which is described in your slides.

At slide (Pump) could you explain the velocity equation ? Many symbols are not described.

Same remark at slide (Nozzle) there is a unit inconsistency in the last equation (vo^2 -2*m*g*h)

At slide (WaterJet), you use a 1/s^2 model (Newton's law) but, in The simulink diagram, it becomes a 1(as^2 + be). Why did you incorporate a viscous term ?

Finally it seems that the mass of the "theoretical box" is 500 kg. What meaning do you give to this "theoretical mass" ?

12 Dec 2013 Transient Catalytic Converter in Simulink Active Heating of During Automotive Start-up for Pollution Reduction Author: John Hedengren FU, Yang

get to learn~thanks for sharing~

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