• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.19 no.1
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• pp.231-238
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• 2019

In this paper, we have studied how to improve the amplifiers efficiency by minimizing the combining loss when several unit power amplifiers are combined to obtain high output power. Specifically, we have developed Ka-band Spatial Combining Amplifier. The fabricated Spatial Combining Amplifier is a Ka-band 20W class SSPA, which uses a 5W class unit amplifier module 8EA designed using a GaN bare die. We also combined The unit amplifier module using 8-way spatial divider and combiner with a hybrid radial structure. The output combining loss of the fabricated spatial coupler is about 0.334dB, which is about 92.6% efficiency. In this paper, we developed a Spatial Combining Amplifier with a maximum saturation output of 10W and a power addition efficiency of over 15%. As a result, we achieved the maximum saturation output of 30W and the power addition efficiency of 19%.

• Journal of Oriental Neuropsychiatry
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• v.28 no.2
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• pp.95-107
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• 2017

Objectives: This study was performed to review studies on Essential Tremor (ET) in Traditional Chinese medicine (TCM). Methods: We reviewed papers in the China National Knowledge Infrastructure (CNKI) from 2007~2016. Search keywords were 原发性震颤, 特发性震颤, essential tremor and idiopathic tremor, and excluded non-clinical studies, non-related to ET or TCM studies, theses for degrees and non-Randomized Controlled Trial (RCT). The quality of the articles was assessed by Jadad scale and the Risk of Bias (RoB). Results: Thirteen studies were selected. 'Criteria for the diagnosis of ET' was most frequently used as diagnostic criteria. 'Tremor rating scale' was primarily used for outcome measurement. Meta-analysis of nine trials revealed the effective rate of acupuncture and Western medicine (WM+Acu) groups was significantly higher compared to the WM group (RR: 1.48, 95 percent CI: 1.20 to 1.82, p=0.0002, $I^2=0$ percent) and tremor rating scale was also significantly decreased in the treatment group (MD: -1.35, 95 percent CI: -2.17 to -0.54, p=0.001, $I^2=0$ percent). Also, effective rates of Electro-acupuncture (EA) and Chinese herbal medicine (CHM) groups were significantly higher than that of the WM group {(RR: 1.53, 95 percent CI: 1.22 to 1.92, p=0.0003, $I^2=0$ percent) in EA vs. WM and (RR: 1.35, 95 percent CI: 1.16 to 1.57, p<0.0001, $I^2=0$ percent) in CHM vs. WM}. However, the quality of selected clinical studies was poor. Conclusions: Treatment of ET in TCM may be more effective and safe than in Western medicine. Therefore, we hope this study will lead to further clinical research on treatment of ET in Korean medicine.