Perhaps you should try some spelling variations:
"defined network optimization algorithm" » "defined network optimization algorithms", "defined network optimisation algorithm", "defined network estimation algorithm", "designed network optimization algorithm"
"modified parameter estimation algorithmss" » "modified parameter estimation algorithms", "modified parameter estimation algorithm", "modified parameter optimization algorithms", "modified parameter estimates algorithmss", "modified parameter optimization algorithmss"

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