Title
A scalable jointree algorithm for diagnosability
Abstract
Diagnosability is an essential property that determines how accurate any diagnostic reasoning can be on a system given any sequence of observations. An unobservable fault event in a discrete-event system is diagnosable iff its occurrence can always be deduced once sufficiently many subsequent observable events have occurred. A classical approach to diagnosability checking constructs a finite state machine known as a twin plant for the system. which has a critical path iff some fault event is not diagnosable. Recent work attempts to avoid the often impractical construction of the global twin plant by exploiting system structure. Specifically, local twin plants are constructed for components of the system, and synchronized with each other until diagnosability is decided. Unfortunately, synchronization of twin plants can remain a bottleneck for large systems; in the worst case, in particular, all local twin plants would be synchronized, again producing the global twin plant. We solve the diagnosability problem in a way that exploits the distributed nature of realistic systems. In our algorithm consistency among twin plants is achieved by message passing on a jointree. Scalability is significantly improved as the messages computed are generally much smaller than the synchronized product of the twin plants involved. Moreover we use an iterative procedure to search for a subset of the jointree that is sufficient to decide diagnosability. Finally, our algorithm is scalable in practice: it provides an approximate and useful solution if the computational resources are not sufficient.
Year
Venue
Keywords
2008
AAAI
local twin plant,global twin plant,algorithm consistency,critical path iff,discrete-event system,diagnosability problem,realistic system,twin plant,scalable jointree algorithm,large system,system structure,message passing,finite state machine,critical path
Field
DocType
Citations 
Bottleneck,Observable,Computer science,Theoretical computer science,Artificial intelligence,Unobservable,Message passing,Synchronization,Algorithm,Finite-state machine,Critical path method,Machine learning,Scalability
Conference
7
PageRank 
References 
Authors
0.71
8
2
Name
Order
Citations
PageRank
Anika Schumann110313.12
Jinbo Huang237121.81