Perhaps you should try some spelling variations:
"modified parameters estimation algorithms" » "modified parameter estimation algorithms", "modified parameter estimates algorithms", "modified parameter optimization algorithms", "modified parameters optimization algorithms", "modified parameters optimisation algorithm", "modified parameters approximation algorithms"
"modified passive estimation algorithm" » "modified pose estimation algorithm", "modified adaptive estimation algorithm"

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

• If you are trying to use Boolean operators, they must be ALL CAPS: (("modified passive estimation algorithm") OR ("modified parameters estimation algorithms"))~.
• Removing quotes may allow a broader search: (( modified passive estimation algorithm ) or ( modified parameters estimation algorithms ))~.
• Adding a wildcard symbol may retrieve word variants: (("modified passive estimation algorithm") or ("modified parameters estimation algorithms"))*.