Objective functions are evaluated at each optimization step. All objective functions are also saved into the MIRaGE project file. Note that you can also export or import an Objective function (in a directory of your choosing). The names of the Objective Functions are also reported in the DAKOTA input file (you can view this input file and test it via the Optimization UI). So if you add multiple functions, all will be used in a single simulation. In the outputs from a given optimization, there will be a separate column for each objective function as calculated along with the parameters that were varied and exported to DAKOTA.