Perhaps you should try some spelling variations:
estimation algorithms » estimation algorithm, optimization algorithms, optimisation algorithm
objective estimation » objective optimization, objective allocation
effective graining » effective gradient, effective reading
graining methods » learning methods, learning method, making methods

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

• Performing a fuzzy search may retrieve terms with similar spellings: (( modified objective estimation algorithms ) or ( effective graining methods algorithm ))~.
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