Abstract: For the situation that bipolar-value fuzzy soft sets information changes with time, the concept of dynamic bipolar-value fuzzy soft set is defined, and relative operations and properties have been discussed, too. The weight determination formulas are obtained based on the logarithmic growth model. Then operation of bipolar-value fuzzy soft sets is defined with aggregation thought and the computational formula of the geometric weighted average operator has been given, and dynamic bipolar-value fuzzy soft sets have been aggregated into collective bipolar-value fuzzy soft set. The optimal decision can be obtained by calculating choice value of objects with the level soft set. A practical example has been analyzed to verify the reasonability and feasibility of the approach.

Key words: group decision making, dynamic bipolar-value fuzzy soft sets, logarithmic growth model, geometric weighted average operator, level soft set

摘要： 针对实际问题中双极值模糊软集随时间变化的影响，定义了动态双极值模糊软集等概念，讨论了相关运算及性质。根据时间权重符合对数增长模型得到权重确定公式。利用集成思想定义双极值模糊软集的运算并给出几何加权平均算子的计算公式，将动态双极值模糊软集集成为综合双极值模糊软集。利用水平软集算出各对象的机会值，得出最优决策。通过实例分析证明此决策方法的合理性与可行性。

关键词: 群决策, 动态双极值模糊软集, 对数增长模型, 几何加权平均算子, 水平软集