Perhaps you should try some spelling variations:
"modified objective optimisation algorithm" » "modified objective optimization algorithm", "modified multiobjective optimization algorithm", "modified objective optimization algorithms", "modified objective estimation algorithms"
"modified staffing estimation algorithm" » "modified staffing optimization algorithm", "modified caging estimation algorithm"

You may be able to get more results by adjusting your search query.

• If you are trying to use Boolean operators, they must be ALL CAPS: (("modified objective optimisation algorithm") OR ("modified staffing estimation algorithm"))~.
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