Perhaps you should try some spelling variations:
"modified multiobjective estimation algorithms" » "modified multiobjective optimization algorithms", "modified multiobjective estimation algorithm", "modified multiobjective optimisation algorithm", "modified multiobjective approximation algorithms"
"modified pulsed optimization algorithms" » "modified pulsed optimisation algorithm", "modified pulsed estimation algorithm", "modified pulsed optimized algorithms", "modified policy optimization algorithms"

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