Perhaps you should try some spelling variations:
"modified passive quantization algorithm" » "modified passive estimation algorithm", "modified adaptive quantization algorithm"
"modified lighting approximation algorithms" » "modified diophantine approximation algorithms", "modified caging approximation 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 passive quantization algorithm"))~.
• Removing quotes may allow a broader search: (( modified lighting approximation algorithms ) or ( modified passive quantization algorithm ))~.
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