Perhaps you should try some spelling variations:
quantization algorithms » estimation algorithms, optimization algorithms
adaptive quantization » adaptive ventilation
modified adaptive » modified passive
df estimation » _ estimation
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 df estimation algorithm ) OR ( modified adaptive quantization algorithms ))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "(( modified df estimation algorithm ) OR ( modified adaptive quantization algorithms ))".
• Adding a wildcard symbol may retrieve word variants: (( modified df estimation algorithm ) OR ( modified adaptive quantization algorithms ))*.