1. The optimum design of the controller of compound active noise cancellation earmuff is discussed. 探讨了复合式有源消声耳罩的控制器的优化设计方法。
2. Noise is another hazard. Working with noisy tools such as jackhammers requires proper, effective use of hearing protection. Ear plugs and earmuff type hearing protection is recommended. 噪音是另一种危险。使用手提钻之类的噪音工具时,必须佩戴有效的听力保护装置。建议使用耳塞和耳罩听力保护装置。
3. L. f. noise can be better attenuated so as to obtain good attenuation characteristics over the entire audible frequency range by using active noise reduction technique in the closed-air type earmuff. 在密闭型耳罩中,利用有源降噪技术可以较好地衰减低频噪声以使整个可听声频率范围内获得良好的衰减特性。