Publications by authors named "Ki-Hyeon Park"

Article Synopsis
  • - This study explores how different waveforms (sine vs square) and frequencies (from 10 Hz to 500 kHz) of radio frequency (RF) energy impact the range of tissue ablation using a specially developed 70-watt RFA generator.
  • - The experiments involved testing various configurations of electrodes and frequencies, observing that a square wave at a frequency of 10 kHz resulted in a larger ablation range compared to a sine wave at 500 kHz.
  • - The findings indicate that the generator can enhance future research on RF ablation techniques, particularly regarding the area and depth of tissue affected during the procedure.
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PAL-XFEL utilizes a three-chicane bunch compression (3-BC) scheme (the very first of its kind in operation) for free-electron laser (FEL) operation. The addition of a third bunch compressor allows for more effective mitigation of coherent synchrotron radiation during bunch compression and an increased flexibility of system configuration. Start-to-end simulations of the effects of radiofrequency jitter on the electron beam performance show that using the 3-BC scheme leads to better performance compared with the two-chicane bunch compression scheme.

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[Purpose] The objective of this study was to examine the effect of ankle strategy exercises on unstable surfaces on balance and walking ability in stroke patients. [Subjects and Methods] Among hospitalized stroke patients, 30 were selected based on the study criteria and were randomly divided into three groups: an ankle strategy group (n=10), balance exercise group (n=10), and control group (n=10). Patients in two groups (ankle strategy, balance exercise group) performed 15-minute exercise sessions three times a week for six weeks.

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[Purpose] The objective of this study was to examine the effect of step climbing exercise on the walking ability of stroke patients. [Subjects and Methods] Among hospitalized stroke patients, 24 were selected based on the study criteria and randomly divided into two groups: an experimental group (12 patients) and a control group (12 patients). The patients in both groups participated in 15-minute exercise sessions three times a week for eight weeks.

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