Abstract: The bucket elimination algorithm and the join-tree reasoning algorithm arc popularly used for automated reasoning. To improve the efficiency of message propagation in the join-tree reasoning algorithm, a new join-tree reasoning algorithm (called JTR) was proposed. Meanwhile, to handle the inefficiency of multi-task automated reasoning of the bucket elimination algorithm BE,a bucket tree reasoning algorithm (named as BJTR)，based on the join-tree structure and message propagation mode in JTR, was further developed from BE. Our study shows that in comparison with the BTE algorithm, the proposed algorithm川丁R improves the time performance while space performance decreases a little. Furthermore, as compared with BE,BJTR effectively reduces the demand on timcoverhead while maintaining a slightly low space performance in the handling of multi-task automated reasoning. Meanwhile, both examples and experimenu demonstrate that BJTR algorithm has an obvious advantage in the time performance for multi task reasoning.

Key words: Automated reasoning, Multi-task, Bucket elimination, Join-tree, Bucket-tree