A transient form of this 
A transient form of this phenomenon is often modeled using lumped system analysis. The transient-line source method or laser-flash method is used to calculate the ability of a material to undergo this process. Values of less than 0.1 for the Biot number imply this process is dominating, and the ratio of the rate of this process to energy storage is given by the (*) Fourier number. In solids, this process occurs via free-electron diffusion and phonon vibration. The rate of this process is equal to the negative k of the temperature gradient in Fourier's law of this process. For 10 points, name this process that competes with radiation and convection, a form of heat transfer that occurs within a solid.
A transient form of this phenomenon is often modeled using lumped system analysis.