DocumentCode :
2455707
Title :
Rollout strategies for sequential fault diagnosis
Author :
Tu, Fang ; Pattipati, Krishna
Author_Institution :
Dept. of Electr. & Comput. Eng., Connecticut Univ., Storrs, CT, USA
fYear :
2002
fDate :
2002
Firstpage :
269
Lastpage :
295
Abstract :
Test sequencing is a binary identification problem wherein one needs to develop a minimal expected cost testing procedure to determine which one of a finite number of possible failure sources, if any, is present. The problem can be solved optimally using dynamic programming or AND/OR graph search methods (AO*, CF and HS). However, for large systems, the associated computation with dynamic programming or AND/OR graph search methods is substantial, due to the rapidly increasing number of OR nodes (denoting ambiguity states) and AND nodes (denoting tests) in the search graph. In order to overcome the computational explosion, the one-step or multi-step lookahead heuristic algorithms have been developed to solve the test sequencing problem. In this paper, we propose to apply rollout strategies, which can be combined with the one-step or multi-step lookahead heuristic algorithms to obtain near-optimal solutions in a computationally efficient manner than the optimal strategies. The rollout strategies are illustrated and tested using a range of real-world systems. We show computational results, which suggest that the information-heuristic based rollout policies are significantly better than other rollout policies based on Huffman coding and entropy.
Keywords :
aerospace testing; automatic testing; fault diagnosis; identification; large-scale systems; probability; sequences; binary identification problem; faulty state probabilities; field maintenance; high safety requirements; information heuristic; large-scale systems; minimal expected cost testing procedure; mission criticality requirements; multi-step lookahead heuristic algorithms; one-step lookahead heuristic algorithms; rollout strategies; sequential fault diagnosis; test sequencing problem; Costs; Dynamic programming; Entropy; Explosions; Fault diagnosis; Heuristic algorithms; Huffman coding; Search methods; Sequential analysis; System testing;
fLanguage :
English
Publisher :
ieee
Conference_Titel :
AUTOTESTCON Proceedings, 2002. IEEE
ISSN :
1080-7725
Print_ISBN :
0-7803-7441-X
Type :
conf
DOI :
10.1109/AUTEST.2002.1047898
Filename :
1047898
Link To Document :
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