Below are two constraint expressions for a mathematical model I presented in a paper. These are the approximate convex lower bounds of the constraints. I am currently trying to replicate the model in this paper using Matlab, but I encountered many problems when constructing this constraint using CVX, such as “Cannot perform the operation: {convex}/ {convex}”. How should I construct this constraint?

I have no idea what those symbols are. I don’t know what are optimization variables, what are nonlinear expressions of optimization variables, and what are input data,

Have you rigorously proven convexity? Follow the standards in this link.

This optimization problem is what I saw in a paper. The specific problem is shown in the following figure

The last two constraints of this optimization problem are non convex, so the author suggests using their convex lower bounds to approximate them. The convex lower bound of the function is shown in the second picture, and this equation is very complex. I can’t do anything about it. In fact, I don’t know if this constraint is really convex after transformation, as the author said. If the CVX toolbox cannot solve this problem, is there any other good way for me to solve this optimization problem?

It would seem you need to re-read the link, and follow its advice.

As I wrote above, I have no idea what those symbols are. You need to put in the effort to understand it, and prove convexity. Perhaps contact the authors of the paper if you need help with that.