Perhaps you should try some spelling variations:
"modified parameter optimization algorithm" » "modified parameter optimization algorithms", "modified parameter optimisation algorithm", "modified parameter estimation algorithm", "modified parameters optimization algorithm"
"modified location estimation algorithms" » "modified location estimation algorithm", "modified location optimization algorithms", "modified location optimisation algorithm", "modified motion estimation algorithms", "modified carbon estimation algorithms"

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 location estimation algorithms") OR ("modified parameter optimization algorithm"))~.
• Removing quotes may allow a broader search: (( modified location estimation algorithms ) or ( modified parameter optimization algorithm ))~.
• Adding a wildcard symbol may retrieve word variants: (("modified location estimation algorithms") or ("modified parameter optimization algorithm"))*.