Focusing candidate generation

We propose fault characteristics as an efficient linear space encoding of the fault behavior of devices. Fault characteristics of a device use the function of the device to suggest how it may not have failed, and, in turn, how the devices at its inputs may have failed. They are compiled for simple devices, and provided as part of the device library. For composite devices, we outline a linear time algorithm to generate relevant fault characteristics. We highlight the merits of this scheme in comparison with a similar recent approach.