Perhaps you should try some spelling variations:
"modified sphere optimization algorithms" » "modified sphere optimisation algorithm", "modified sphere estimation algorithm", "modified sphere optimized algorithms", "modified sphere estimation algorithms", "modified stage optimization algorithms", "modified response optimization algorithms"
"modified parameters estimation algorithms" » "modified parameter estimation algorithms", "modified parameter estimates algorithms", "modified parameter optimization algorithms", "modified parameters estimation algorithm", "modified parameters optimisation algorithm", "modified parameters approximation algorithms"

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