本論文利用有限元素法的模擬，實現了對新生兒保溫箱內噪音的數值分析。早產兒由於身體發育尚未成熟，必須暫時待在保溫箱內接受一些例如呼吸器、心電圖儀和腦波儀等輔助儀器監視其生理機能，讓醫護人員對有異常情況的嬰兒進行紀錄及適當的調整，但是這些儀器再加上其它如醫院內的對講機、警示器等所發出的聲音都將形成各種噪音，尤其對於保溫箱內敏感的早產兒會產生干擾，造成不安。為避免保溫箱內早產兒的發育受到噪音影響，本論文採用主動式噪音控制（ANC）的理論，使用1×2×2單參考/多輸出之多通道FXLMS演算法的方法，利用有限元素法的模擬產生保溫箱內的靜音區，以達到降低噪音的影響。並且將模擬分析出來的結果，使更方便的探討揚聲器的數量及擺放的位置對消音效能的影響。

　　The purpose of this paper is to simulate the active noise control (ANC) technique used in the incubator. In this paper, the numerical simulations of acoustic noise cancellation by means of the finite element method (FEM) are demonstrated. There are some noises around the incubators, including the sounds generated by the medical instruments, personnel, the ventilator equipment, the rings of the intercoms, alarms etc. Exposure to these noises will disrupt premature infants sleeping in the incubators, may cause sensorineural damage, induce stress, and contribute to language or auditory processing disorders. In order to reduce noise level in the incubators, we use ANC method and adopt 1×2×2 multi-channel FXLMS algorithm to generate a quite zone around the infants. From the numerical simulation results, we realize how to determine the proper position of the canceling loudspeaker and to improve the quality of incubator.

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