Table 1.

Some significant developments of modern scientific tools in Taiwan and Korea since 1950s.

Time-line	Publications/Researchers	Significant developments
1950s	Zhu Yan (China)	•Development of lever-type pulse plethysmograph.
1960s	Zhao-Fu, Fei (China)	•Focus on the study of the pulse wave spectrum using Frequency Domain Analysis.
1976	Shu-You, Wang (Taiwan)	•Developed the pulse sphygmograph device connected to computers to perform pulse waveform analysis [4].
1984	Ling-Yun, Wei (Taiwan)	•Studied the difference in radial pressure pulse waves using Spectral Energy Ratio. Found that the spectral energy had large variations above 10 Hz in unhealthy patients [5].
1987–1989	Wei-Kung, Wang (Taiwan)	•Utilized Fast Fourier Transformation (FFT) to analyze the pulse waveform. •Introduced “Resonance Theory”. The resonance frequencies of organs were found corresponded to the spectral-domain harmonics of the arterial pulse. •Focused on low-frequency Spectral Energy 0–10 Hz [6].

2005–2012	Chin-Ming, Huang (Taiwan)	•Further developed pulse sphygmograph based on the device model from Prof SY Wang. •Found that acupuncture had a more significant effect on Spectral Energy 10-50 Hz and 13–50 Hz than that on Spectral Energy 0–10 Hz [7]. •Reported that the spectral domain analysis provided a more in-depth understanding of the relationship between the arterial pulse and disease conditions [8]. •Concluded that majority of the disease conditions showed a response in Spectral Energy 13–25Hz and the peak was frequently found at 13–16 Hz. •The studies had included Time Domain Analysis and Frequency Domain Analysis.
2013	Korea Institute of Oriental Medicine, Daejeon (Korea)	•Developed pulse tonometric device based on sensor displacement [9].