Perhaps you should try some spelling variations:
"modified objective allocation algorithms" » "modified objective estimation algorithms", "modified objective approximation algorithms"
"modified invasive ventilation algorithm" » "modified invasive estimation algorithm", "modified invasive estimation algorithms", "modified invasive evolution algorithm", "modified adaptive ventilation algorithm", "modified passive ventilation 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 allocation algorithms") OR ("modified invasive ventilation algorithm"))~.
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