“…In the context of database models, fuzzy information modeling has been extensively investigated in [17,54,65,67,82]. To model uncertain data and complex-valued attributes as well as complex relationships among objects, which are required in many application domains [12,15,19,45,69,71,80,83], current efforts have concentrated on the fuzzy conceptual data models (e.g., fuzzy ER/EER data model [21,29,92,97] and fuzzy UML data model [51]) and the fuzzy object-oriented databases [16,24,30,34,56,91]. The conceptual design of fuzzy relational databases using the fuzzy ER data model and the fuzzy UML data model was investigated in [20,55], respectively, and the conceptual design of fuzzy object-oriented databases using the fuzzy EER data model and the fuzzy UML data model was presented in [53,58], respectively.…”