Perhaps you should try some spelling variations:
"modified network optimization algorithms" » "modified network optimisation algorithm", "modified network estimation algorithm", "modified network optimized algorithms", "certified network optimization algorithms", "defined network optimization algorithms", "modified near optimization algorithms"
"modified invasive estimation algorithms" » "modified invasive estimation algorithm", "modified invasive optimisation algorithm", "modified invasive approximation algorithms", "modified invasive ventilation algorithms", "modified passive estimation algorithms"

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