Problem while modelling Pareto Optimal Solution

[Balu6667]

Respected Everyone, please check the below-attached code.

This is a multi-objective scheduling technique.
While optimizing the objectives separately, they are working fine, but when I tried to use Pareto optimal, I got constant optimized values instead of getting mutually varying values.
Please provide the error in case anyone finds it in the below attached and posted.
Thank you in advance.

Untitled_8.gms

Pareto Optimal Problem

(15.52 KiB) Downloaded 25 times

[bussieck]

Have you ever looked at the ranges parameter? I get:

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----    243 PARAMETER ranges  
OF1min 625.394,    OF2max  35.830,    OF2min  35.830,    OF1max 625.394

Not much wiggle room. When I try to explicitly min/max the two objectives via:

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solve problem using MINLP minimizing of1; ranges('OF1min') = of1.l;
solve problem using MINLP maximizing of1; ranges('OF1max') = of1.l;
solve problem using MINLP minimizing of2; ranges('OF2min') = of2.l;
solve problem using MINLP maximizing of2; ranges('OF2max') = of2.l;

I get

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----    250 PARAMETER ranges  
OF1min 625.394,    OF1max 985.626,    OF2min  35.830,    OF2max  35.830

So not much room to get differences for OF2 and hence to point in doing multi-objective optimization. It's enough to min OF1.

-Michael

PS I used global MINLP solver BARON.

[Balu6667]

Respected sir,
Thank you for your answer.
As you have mentioned that there is no room for doing two objectives, I tried to make it into a single objective as coded in the below-attached files. but I am getting the error while doing so.

Sir, can you please resolve the issue and provide me with the path to get it for the below-attached codes (in between both the below codes I changed the formula of the previous code file's second objective ).

Thanks in advance.

Untitled_12.gms

CODE-12

(17.22 KiB) Downloaded 23 times

[bussieck]

Sorry, no idea what you are asking for. I download both models. They both compile and solve fine. What do you think is the matter with them?

-Michael

[Balu6667]

respected sir,
while I was trying to optimize, it was showing.

DICOPT: Terminating
DICOPT: stopped on NLP worsening.

Thank you in advance.

[Balu6667]

Respected sir,

For the above-attached codes (Untitled 11 and 12), when I was trying to optimize, it was showing the following errors.

DICOPT: Terminating
DICOPT: stopped on NLP worsening

Thank you in advance. Please provide the solution.