If you want to produce something simular.
- You let the Ramp be your UV, so pipe that to an OSL UV Transform node.
- Pipe noise to UV Transforms offset, to offset the linear arnold ramp.
- Plug a float node into scale of noise and set it to 0.8
We now have this frequency feature build and working.
Note I use 3DS MAX, but you would wire it up in the exact same sequence.