Perhaps you should try some spelling variations:
"modified df estimation algorithms" » "modified df estimation algorithm", "modified df optimization algorithms", "modified df optimisation algorithm", "modified _ estimation algorithms", "modified adam estimation algorithms", "modified bi1 estimation algorithms"
"modified adaptive ventilation algorithm" » "modified adaptive estimation algorithm", "modified adaptive evolution algorithm", "modified adaptive quantization algorithm", "modified invasive ventilation algorithm", "modified passive ventilation algorithm"

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

• Performing a fuzzy search may retrieve terms with similar spellings: (("modified df estimation algorithms") or ("modified adaptive ventilation algorithm"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("modified df estimation algorithms") OR ("modified adaptive ventilation algorithm"))*.
• Removing quotes may allow a broader search: (( modified df estimation algorithms ) or ( modified adaptive ventilation algorithm ))*.