Perhaps you should try some spelling variations:
estimation algorithms » estimation algorithm, optimization algorithms, optimisation algorithm
staffing estimation » staffing optimization
one approximation » time approximation, _ approximation, rough approximations
modified staffing » modified caging
modified one » modified male, modified near, modified orca

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

• Performing a fuzzy search may retrieve terms with similar spellings: (( modified one approximation algorithms ) or ( modified staffing estimation algorithms ))~.
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