Perhaps you should try some spelling variations:
optimization algorithms » optimisation algorithm, estimation algorithm, optimized algorithms
objective optimization » multiobjective optimization
estimation algorithms » estimation algorithm, optimisation algorithm, approximation algorithms
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 algorithms ) OR ( modified objective optimization algorithms ))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "(( modified df estimation algorithms ) OR ( modified objective optimization algorithms ))".
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