Perhaps you should try some spelling variations:
"modified lighting approximation algorithms" » "modified diophantine approximation algorithms", "modified caging approximation algorithms"
"modified parameter optimized algorithm" » "modified parameter optimization algorithm", "modified parameter optimized algorithms", "modified parameter optimizer algorithms"

You may be able to get more results by adjusting your search query.

• If you are trying to use Boolean operators, they must be ALL CAPS: (("modified lighting approximation algorithms") OR ("modified parameter optimized algorithm"))~.
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