摘要或動機

本實驗針對隔音材質的特性，如各孔板之孔徑、開孔率，並以夾層做不同孔板配置進行研究。本主題共進行三階段的實驗。第一階段探討不同材質的影響，因材質加工問題，實驗誤差過大；第二階段改以PP 塑膠板探討，因儀器誤差，數據難以解析；第三階段仍以PP 塑膠板探討，並修正實驗步驟，以降低實驗誤差。本報告乃以第三階段實驗結果做探討。為了提高實驗準確度，將整個實驗分成若干組，在實驗前後以空白測試，以減低實驗誤差。利用Excel 軟體，進行各組實驗數據噪音傳送損失之修正與分析。本試驗以125Hz、250Hz、500Hz、1000Hz、2000Hz 及4000Hz 六段週波頻率做測試。由分析結果顯示，孔徑與開孔率、同心圓的排列方式，對噪音傳送損失有顯著的影響。;This experiment is to focus on the properties of sound barriers, such as hole diameter, open areas, and the layout of holing boards. We have performed experiments in three steps. In the first step, we discussed the differences between different kinds of material but found many errors caused from faults in the process of making boards. So in the second step, we chose the ploy-propene board but still found errors from instruments. And in the final step, we used the ploy-propene board again and modified the experiment procedure to lower the error from instruments. The report is based on the final step data. With a view to raise the precision of the experiment, we divided the experiment into several parts with the blank test. We modified and transferred the original data to the noisy transfer loss (TL) in the same intensity level, and analyzed the data with Microsoft Excel. In experiment, we detected the noise-pollution level (dB) in the frequency of 125Hz, 250Hz, 500Hz, 1000Hz, 2000Hz and 4000Hz. According to the result, the hole diameter, open area and the layout of concentric circle have a significant influence on TL.