Data, Digital Twin, Statistics, Physics, Water Filtration.
<1 nm, nanofiltration 1–2 nm, ultrafiltration 2–100 nm, and microfiltration 100 nm–10 μm). Top: Example of a measured variable (flux through a membrane) and input control variables causing it (pressure and crossflow). Bottom: Example of a hidden (unmeasurable) state: prediction of the mean value