本研究利用田口方法分析訂製往復性水假體在128 切電腦斷層掃描儀不同心臟掃描參數對假體影像解析度尋 求最佳化條件。同一組織在不同的掃描條件下得到的殘影值可能產生相當大的差異，從而導致影像解析度的變 化。本研究利用訂製往復性水假體中一段速度及振幅取在30 毫米的位置，在不同攝影條件下進行電腦斷層掃描， 利用原廠量測軟體量測數值，再利用田口分析法分析各參數振幅殘影影響的程度，結果找到影響振幅殘影的重要 因子是Rotation time，其次是Pitch，次要因子是slice thickness;在交互作用分析中可知Rotation time 和 collimation 具交互作用;並使用變異數分析ANOVA(Analysis of Variance)驗證研究所得結果，亦顯示99%以上信心水準，具有 統計上顯著的意義。實驗並找到不同掃描條件其殘影最小的參數設定，建議選擇0.4 秒的掃描時間，40*0.625 的 collimation，0.423 的Pitch，2 毫米的切片厚度，期望降低心臟影像檢查時因為臟器位移而造成的振幅殘影進而影 響影像檢查的解析度。

In this study, Taguchi methods to evaluate the reciprocating water phantom to take 128-slice computer tomography have different scanning parameter to find the optimal image resolution. Residual length of the same tissue at different scanning parameter may variation to change image resolution .Research on the moving phantom take some speed and amplitude of 30 mm in the position, computed tomography under different parameters. Taguchi methods analysis parameters produce different residual length, and find the major factor is rotation time , secondary is pitch ,minor factor is slice thickness. Furthermore, the optimized recommendation of the factors was also confirmed by the ANOVA and was shown above 99% confidence level in statistical significance. The optimized setting were: (1) 0.4 sec rotation time, (2) 40*0.625 collimation, (3) 0.423 pitch, (4) 2 mm slice thickness. The recommended combination of the factors could successfully reduce the motion uncertainties of the heart image examination.