periodicit周期性, 周波periodicadj.周期的；定期的；间歇的；完句的periodic instanton周期瞬子periodic psychosis周期性精神病periodic sequenees周期序列Periodic point set集值映射periodic breathing周期性呼吸periodic character周期特征Periodicity energy周期能量periodic attractor周期吸引子periodic intensity周期性强度periodic collinear循环直射