视频显示终端作业过程中的脉搏信号分析研究

目的：针对长期视频显示终端（VDT）作业引发的疲劳健康问题，设计VDT作业疲劳实验，探求实验前后脉搏参数的变化，为VDT作业疲劳的评价提供方法。方法：筛选30名健康在校大学生进行试验，受试者进行连续4 h的静态计算机游戏操作，每0.5 h采集2 min指端容积脉搏波数据，在实验前后对受试者进行疲劳症状问卷调查。分析提取脉率及脉率变异性参数、指脉搏波波形特征参数，并对比实验前后脉搏波波形图的变化。结果：以疲劳量表FS-14为标准，疲劳实验后受试者精神与躯体疲劳度均有所上升。以Rechichi提出的视疲劳判断标准，疲劳试验后受试者均处于视觉疲劳状态。受试者在VDT作业疲劳实验前后其心率（HR）指标具有显著性差异，且呈下降趋势；脉率变异性算得RMSSD及SDNN指标具有显著性差异，且呈上升趋势；指脉脉搏波波形特征参数K,在实验前后呈波动性上升趋势。结论：脉率及其部分变异性参数、部分脉搏特征参数具显著性变化，脉搏波波形图在VDT作业过程中有趋势性的变化，脉搏波在VDT作业疲劳的监测中具有应用价值，有望成为评价VDT疲劳状态的指标。

Analysis on the pulse wave signal in the process of visual display terminal operation

Objective： To conduct an experiment of the visual display terminal work during which we analyzed the changing of the pulse wave signal to search the objective indices for diagnosing and assessing fatigue induced by the VDT work Methods： Thirty healthy undergraduates were required to attend the experiment during which the tester continued operating the static PC for 4 hours, and we collected the pulse wave of local blood volume in the finger tip for 2 minutes for each 30 minutes. The tester participated in the fatigue symptom inventory before and after the test. After the experiment, we analyzed the heart rate and pulse rate variability, the pulse wave characteristic values and the pulse contour which had been normalized. Results： By the standard of the Fatigue Scale-14, the fatigue degrees of the testers were all raising up. By the standard of Rechichi’s judging criterion, the testers were all in visual fatigue status after the experiment. There were significant differences of HR before and after the experiment which is clearly declining. The index RMSSD and SDNN of pulse rate variability had significant differences and were all raised up. The pulse contour characteristic value （K’） was increasing in the experiment. Conclusion：the heart rate, pulse rate variability and some parameters of pulse wave characteristic values had significant changes and the wave form of pulse had the tendency changes during the VDT work. The pulse wave has the promising prospect of applying to monitor the fatigue of the VDT works, also it is possible to put it into use as the index of evaluate the fatigue status.