一般人在長時間行車下常會出現昏昏欲睡、反應緩慢的現象，如果沒有即時的停車休息，將可能釀成嚴重的交通事故。所以本論文致力於分析疲勞度與心律變異度之間的相關性，觀察人體在一般狀態與疲勞狀態的生理變化。而本論文透過心電圖量測，將心律變異訊號擷取出來，再根據心律變異度相關參數之國際標準進行時域及頻域上的分析，而在頻域方面，我們透過快速傅立葉轉換將心律變異訊號轉換到頻譜，並繪製功率頻譜密度圖(Power Spectral Density, PSD)，而透過時域與頻域的相關參數，我們便可以進行疲勞度之分析。由實驗結果發現，在疲勞狀態下心跳、心跳間隔差值的標準差(SDNN)、相鄰心跳間隔差值的方均根值(RMSSD)參數的數值比非疲勞狀態小，而頻域上的參數，如LF(Low Frequency)、LF/HF Ratio數值在疲勞時呈現上升趨勢，HF(High Frequency)則為下降趨勢。

Most people often appear fatigued and dulled response during the long time drive. If drivers do not stop and take a rest immediately, it would cause a serious accident. Therefore, this paper focuses on the correlation between fatigue and heart rate variability. We observe the physiological changes from general state to fatigue states.This paper extracts the heart rate variability signal by ECG signal. According international standards, we compute heart rate variability in time domain and frequency domain parameters. In the frequency domain, we convert the heart rate variability to frequency domain by FFT (Fast Fourier Transform) and draw PSD (Power Spectral Density) figure. We use time domain and frequency domain parameters to analyze the degree of fatigue.We found that in fatigued state, the heart rate, SDNN and RMSSD parameters are lower than normal state. And the frequency parameters, like LF, LF/HF Ratio are increasing and HF is decreasing in fatigued state.

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