System-level diagnosis: analysis of two new models (Q1092012)

The two major digraph models of system-level diagnosis have been thoroughly analyzed. In this paper, we present two variations of the classic digraph models and discuss their viabilities. Then, we present characterization theorems for t-diagnosability (i.e., describe characteristics and assumptions which enable us to determine the status of the units in a system given the test results and that the number of faulty units does not exceed t). We also present one-step and adaptive diagnosis algorithms. We show that one of our algorithms is optimal and describe cases in which diagnosis in our models requires fewer test results and less restrictive topologies.