N glossary entries

A frequency at which a system tends to oscillate when disturbed without continuing excitation.

The Navier-Stokes equations are the governing momentum-balance equations for viscous fluid flow, relating acceleration, pressure gradients, viscous stresses, and body forces.

Feedback that subtracts a portion of output from input to reduce error and stabilize behaviour.

A computational model made of connected units whose parameters are trained from data.

An iterative root-finding or optimization method using local derivative information.

Noise figure measures how much a component, receiver, or network degrades signal-to-noise ratio compared with an ideal noiseless device.

Inspection methods that evaluate materials or components without impairing future service.

The degree to which a material's fatigue strength is reduced by notches or geometric discontinuities.

A dimensionless number comparing convective heat transfer to conductive heat transfer.

A Nyquist plot is a complex-plane plot of frequency response used with the Nyquist stability criterion to assess closed-loop stability.