You can adjust the weights of the physical restraint types corresponding
to the strand and sheet restraints (phi_psi_dihedral and h_bond,
respectively) there.
In case you wish to delve further into this I attach at the end the
piece of code that I use to add the restraints:
This is a very odd way to add restraints (any time you find yourself
calling a Python function starting with a single underscore, you are
probably doing the wrong thing!) The usual way is to subclass and
override the special_restraints() method: