Template:Generalized eyring relationship

Introduction
The generalized Eyring relationship is used when temperature and a second non-thermal stress (e.g. voltage) are the accelerated stresses of a test and their interaction is also of interest. This relationship is given by:


 * $$L(V,U)=\frac{1}{V}{{e}^{A+\tfrac{B}{V}+CU+D\tfrac{U}{V}}}$$


 * where:

•	   is the temperature (in absolute units ).

•	 $$U$$ is the non-thermal stress (i.e. voltage, vibration, etc.). $$A,B,C,D$$ are the parameters to be determined.

The Eyring relationship is a simple case of the generalized Eyring relationship where $$C=D=0$$  and  $${{A}_{Eyr}}=-{{A}_{GEyr}}.$$ Note that the generalized Eyring relationship includes the interaction term of $$U$$  and  $$V$$  as described by the  $$D\tfrac{U}{V}$$  term. In other words, this model can estimate the effect of changing one of the factors depending on the level of the other factor.