Future work

The sound absorption of rWPCs examined by impedance tube existed variation with positioning (rotation). Therefore, for more accurate comparison, it would be better to repeat the tests of all groups in the reverberation room.

The LWS system in this study was built as a simple ensemble of garden modules consists of plants in pots with plant cases and rWPCs. For practical application, the specific design of rWPCs should be developed that it would actually hold plants without assistance of extra equipment. The sound attenuation performance should be confirmed in such a ready system, with insertion loss and sound absorption properties both possible for measurement, further determining the effect of supporting system for noise reduction.

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