Dual PWM双PWMdualadj.双重的；成双的n.双数dual-rotation propeller共轴反转螺旋桨dual scott continuous map对偶Scott连续映射dual sub - bands method对偶法dual-pressure preformer弹簧模预压机dual use mine hybrid mine两用地雷dual filtering flow model双渗流模型Dual-transistor forward双管正激Dual Certificates' Systemdual channel distribution双渠道分销dual coated optical fiber双涂覆层光纤