Based on the analysis and study of Dubois-Prade(DP) evidence theory, for the defects of the combination rule
of DP, three kinds of reasons are concluded, which lead to the invalid of evidence. Based on the combination rule of
DP, modified factor is introduced, and a modified Dubois-Prade combination rule(MDP) of evidence theory is proposed.
Numerical examples show that the MDP combination rule works effectively in dealing with consistent evidence, high
conflicting evidence and dynamic information fusion.