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    1. <span id="cqqwa"><output id="cqqwa"><nav id="cqqwa"></nav></output></span>
    2. Industry dynamics

      On the Basic Nature of Sound

      I. Sound Generation Sound comes from the vibration of an object and is the sound wave produced by the vibration of an object. In the research of acoustic technology, we call the object that can produce sound sound source. Sound source is no...

      Understanding the Enemy of Human Beings-the Harm of Noise Po

      Noise refers to the sound produced by the vocal body when it vibrates irregularly. Sound is produced by the vibration of an object and propagates in the form of waves in a certain medium, such as solid, liquid and gas. Noise pollution is us...

      Development Review of Noise Control Industry in 2018 and Dev

      I. Comments on the Industry in 2018 1. Major Policies On September 7, 2018, the legislative plan of the 13th Standing Committee of the National Peoples Congress was promulgated. The Law of the Peoples Republic of China on the Prevention and...