add explaination for log densitive feat

[xhebox]

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[LGTM Timeline notifier]

Timeline:

• 2024-03-15 01:49:48.697315206 +0000 UTC m=+995815.719561594: ☑️ agreed by hfxsd.
• 2024-03-15 03:19:54.890977361 +0000 UTC m=+1001221.913223746: ☑️ agreed by Oreoxmt.

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[hfxsd]

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