If the temperature is below setpoint, the output will be on longer; if the temperature is too high, the output will be off longer. The third controller type provides proportional with integral and derivative control, or PID.
Noise figure. Noise figure (NF) and noise factor (F) are measures of degradation of the signal-to-noise ratio (SNR), caused by components in a radio-frequency (RF) signal chain. It is a number by which the performance of an amplifier or a radio receiver can be specified, with lower values indicating better performance.
are sometimes expressed in NC (Noise Criterion) ratings. Concert halls and recording studios aim for ambient noise level ratings of NC-15 to NC-20; NC-15 is considered the lowest level that is feasible to achieve outside the laboratory. I hope this gets you started in the right direction!