Perhaps you should try some spelling variations:
"modified rough approximations algorithms" » "modified rough approximation algorithms", "modified rough approximation algorithm", "modified one approximation algorithms"
"modified parameters estimation algorithms" » "modified parameter estimation algorithms", "modified parameter estimates algorithms", "modified parameter optimization algorithms", "modified parameters estimation algorithm", "modified parameters optimization algorithms", "modified parameters optimisation 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 parameters estimation algorithms") OR ("modified rough approximations algorithms"))~.
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