Perhaps you should try some spelling variations:
"modified network optimization algorithm" » "modified network optimization algorithms", "modified network optimisation algorithm", "modified network estimation algorithm", "certified network optimization algorithm", "defined network optimization algorithm", "modified near optimization algorithm"
"modified changing estimation algorithms" » "modified changing estimation algorithm", "modified changing optimization algorithms", "modified changing optimisation algorithm", "modified channel estimation algorithms", "modified charging station algorithms", "modified caging estimation algorithms"

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