Perhaps you should try some spelling variations:
optimization algorithms » optimisation algorithm, estimation algorithms, optimized algorithms
invasive estimation » invasive ventilation
modified invasive » modified passive
df optimization » _ optimization, qoe optimization, _ optimisation
modified df » modified _, modified adam, modified bi1

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

• Performing a fuzzy search may retrieve terms with similar spellings: (( modified invasive estimation algorithm ) or ( modified df optimization algorithms ))~.
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