Perhaps you should try some spelling variations:
estimation algorithms » optimization algorithms, optimisation algorithm, approximation algorithms
objective estimation » objective optimization, objective allocation
pulse estimation » pulses estimation, pose estimation, sphere estimation
modified pulse » modified male, modified passive

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

• Performing a fuzzy search may retrieve terms with similar spellings: (( modified pulse estimation algorithm ) or ( modified objective estimation algorithms ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( modified pulse estimation algorithm ) OR ( modified objective estimation algorithms )).
• Adding a wildcard symbol may retrieve word variants: (( modified pulse estimation algorithm ) or ( modified objective estimation algorithms ))*.