Fig. 5. Iterative loop of optimization work flow, AC (A1-A3), DT (DT1- DT3) and inside-MRTOF electrodes (negative-voltage Lens electrodes) are the variables used in this work. Manual initial input from prior measurements has been used for initialization.
An overview of the object function value changing during a series of optimizing simulations as the iteration number increases is shown in Fig. 6. One noticeable trend in simulation result is that the value of the feedback function consistently decreases with the algorithm performing, especially rapidly at the beginning, while towards the end, the final convergence tends to be slow, as the simplex has already contracted and the function value remains unchanged. This indicates that taking advantage of the efficiency of the earlier optimization could quickly encourage the process. By continuously modifying the electrode potentials from every previous simulation, an acceptable local-minimum voltage configuration in a specific searching area would be obtained.
Fig. 6. Objection function values of various optimizations as functions of the iteration number. (A), (B), and (C) represent three different optimization rounds for different choices of electrodes using subsets as described in the text.