Problem with definition

Hello,

I am a beginner in gams

I have the attached gams file to see my sets.

I and J are the same exactly so would it be right to do alias(I,j)? If not, do I have to define j as a new set? and How can I define the two equations found here

Thank you.
APO PROJECT 4 (3).gms (8.31 KB)
Equation wanted.JPG
Equation 2.JPG