Perhaps you should try some spelling variations:
"modified staffing optimization algorithms" » "modified staffing optimisation algorithm", "modified staffing estimation algorithms", "modified staffing estimation algorithm", "modified caging optimization algorithms"
"modified coverage approximation algorithms" » "modified average approximation algorithms"

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 staffing optimization algorithms") OR ("modified coverage approximation algorithms"))~.
• Removing quotes may allow a broader search: (( modified staffing optimization algorithms ) or ( modified coverage approximation algorithms ))~.
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