These show that vegetation dam can reduce starting drag force and starting frequency of sediment in upper reaches. And can make athletic sediment deposit.
说明植物坝可以减小泥沙的起动拖曳力，降低上游泥沙的起动频率，并能使运动的泥沙在坝上游沉积下来。
2
The control effect of electromagnetic force on cylinder wake, lift force and drag force , which was caused by alternating current, is related to its frequency.
而交流电所产生的电磁力对于绕流涡街、升力、阻力的控制作用，则与所使用的频率有关。
3
Based on the G-M system contrast to the system of frequency conversion, the paper introduces the improvement of advocate-drag system of dragon-planer of transducer of B2012A and PLC.