Perhaps you should try some spelling variations:
"modified risk optimization algorithms" » "modified risk optimisation algorithm", "modified risk estimation algorithms", "modified risk estimation algorithm", "modified robust optimization algorithms", "modified _ optimization algorithms", "modified game optimization algorithms", "modified bi1 optimization algorithms"
"modified objective estimation algorithmss" » "modified objective estimation algorithms", "modified objective estimation algorithm", "modified objective optimization algorithmss", "modified objective allocation algorithmss"

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