作者单位: | 1. Research Group on Natural Computing, Department of Computer Science and Artificial Intelligence, University of Seville, Avda. Reina Mercedes, 41012 Sevilla, Spain; 2. Department of Computer Science, The University of Sheffield Regent Court, Portobello Street, Sheffield S1 4DP, UK; 3. Romanian Academy, Institute of Computer Science, Blvd. Carol I nr.11, 700505, Ia?i, Romania |