Perhaps you should try some spelling variations:
"modified df optimisation algorithm" » "modified df optimization algorithms", "modified df estimation algorithms", "modified _ optimisation algorithm", "modified _ optimization algorithm", "modified qoe optimization algorithm", "modified adam optimisation algorithm", "modified bi1 optimisation algorithm"
"modified network estimation algorithm" » "modified network optimization algorithm", "certified network estimation algorithm", "defined network estimation algorithm", "modified near estimation algorithm"

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