本論文內容主要是針對近似聲源法聲源不連續的問題，利用有限元素法（Finite Element Method）把聲源的分佈線性化，以及使用三角型高斯積分法(Gauss Legendre Quadrature over a triangle)進行面積分的計算，把近似聲源法發展到線性分佈聲源法，再配合聲音全像（Acoustical Holography）量測技術對訊號進行分析，繪製出整體及各個主要噪音頻率之聲壓等高線分佈圖，以確定噪音產生的主要位置。
研究中也證明了線性分佈聲源法可以改善平面近似聲源法在預估離聲源很近之聲場所遇到的兩個問題。第一個是誤差太大的問題，第二個是當聲源不在虛擬聲源面的格點上時，平面近似聲源法會把聲源平均分配給周圍的格點，造成錯誤的結果。並於文中做了近似聲源法與線性分佈聲源法在3種不同聲源與不同的量測條件下的誤差分析之比較，驗證了線性分佈聲源法的可行性。

In the present study, an innovation to find out the location of the noise in a system is explored. By using the Finite Element Method and Gauss Legendre Quadrature over a triangle, an innovation which is linear distribution source method has been developed. This innovation, coordinated with the technology of the measurement of acoustical holography, is able to draw up the sound pressure contour distribution maps of overall frequency and each dominant noise frequency. Also the main position of noise produced in the system can be determined.
In addition, this research had proven the linear distribution source method may overcome the error of predicting sound pressure within a prediction distance of the plane version of similar source method. Besides, it can reduce the effect of measuring error and improve the accuracy of the analysis.
Furthermore, comparison of error analysis between the similar source method and the linear distribution source method has also been made for three different sources and conditions. It has confirmed the feasibility of linear distribution source method.

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