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.