Perhaps you should try some spelling variations:
"modified objective optimization algorithm" » "modified multiobjective optimization algorithm", "modified objective optimization algorithms", "modified objective optimisation algorithm", "modified objective estimation algorithm"
"modified channel estimation algorithms" » "modified channel estimation algorithm", "modified channel optimization algorithms", "modified channel optimisation algorithm", "modified channel excitation algorithms"

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• Performing a fuzzy search may retrieve terms with similar spellings: (("modified channel estimation algorithms") OR ("modified objective optimization algorithm"))~.
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