• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.21 no.9
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• pp.842-849
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• 2011

The human ear canal amplifies the sound pressure level at specific frequency bands. The characteristics of the ear canal are very similar to those of curved cylindrical tube. In this study, the characteristics of sound transfer in human ear canal were measured and the acoustical space of ear canal was reproduced from the canal cavity geometry. For the measurement of sound transfer function in ear canal, a probe microphone and a reference microphone were used. The sound transfer functions were measured for 5 human subjects. To reproduce the acoustical space of the ear canal, two kinds of ear simulator were designed. The first one is a straight cylindrical tube type and the other is a real-shape ear of which geometry was taken from a micro-CT scanning of a human ear. The characteristics of the reproduced apparatus were compared with those of the human and a commercial ear simulator, RA0045 of G.R.A.S. Inc. The comparison results show that the developed apparatus well represent the ear canal characteristics in the low frequency, but have limited coincidence in level over high frequency range.

• Bangmulgwan gwa yeongu (The National Museum of Korea Journal)
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• v.1
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• pp.234-257
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• 2024

Great Dharani Sutra of Undefiled Pure Light (Gwi) (LKH 10703) donated by the family of the late Lee Kun-Hee to the National Museum of Korea in 2021 is a calligraphy album consisting of sixty-two leaves compiled using butterfly binding. It contains Great Dharani Sutra of Undefiled Pure Light, "Record of the Production of Mugujeong Pagoda by the Order of King Munseong," a postscript by Kim Jeonghui, and an appreciation record by Oh Sechang. This paper has revealed that this album is identical to the material that Suematsu Yasukazu introduced in Volume 15 of the journal Cheonggu hakchong in 1934 and that it includes elaborate copies of Great Dharani Sutra of Undefiled Pure Light and "Record of the Production of Mugujeong Pagoda by the Order of King Munseong" on yellow Chinese paper, both of which were excavated from inside the Mugujeong Pagoda at Changnimsa Temple in Gyeongju in 1824. It has also reconfirmed that it is highly probable that the Great Dharani Sutra of Undefiled Pure Light that Jo Byeongsun, the former director of the Seongam Old Books Museum, unveiled in 1998, is a transcription of the original sutra excavated from Mugujeong Pagoda at Changnimsa Temple in Gyeongju. Moreover, it has concluded that the Great Dharani Sutra of Undefiled Pure Light owned by Park Cheolsang is likely to be another example of copying the transcription of the original sutra excavated from the Mugujeong Pagoda at Changnimsa Temple in Gyeongju. In the album of copies donated by the estate of Lee KunHee, six of the Chinese characters promulgated by Empress Wu were used fifteen times in total. Four of the characters of Empress Wu were utilized ten times in the Great Dharani Sutra of Undefiled Pure Light (national treasure, Bulguksa Temple collection) found among the reliquaries from the Three-story Stone Pagoda at Bulguksa Temple in Gyeongju and were also seen in the album of copies donated by the estate of Lee Kun-Hee. The use of the same characters of Empress Wu and other variant characters suggests that both the album of copies donated by the estate of Lee Kun-Hee and the Bulguksa sutra were based on an edition distributed in the Unified Silla Period during the eighth century. Kim Jeonghui confirmed the exchange of calligraphy between Korea and China through studies on bronze and stone epigraphs. He believed that the Great Dharani Sutra of Undefiled Pure Light and "Record of the Production of Mugujeong Pagoda by the Order of King Munseong" excavated from Mugujeong Pagoda at Changnimsa Temple were authentic materials showing the elegant calligraphic styles that prevailed before the Ouyang Xun style. Thus, the album of copies donated by the estate of Lee Kun-Hee holds great historical and artistic significance in that it is a rare example of Kim Jeonghui's evidential study of a transcribed sutra and an original record of the production of a pagoda from the Unified Silla period.

• Korean Journal of Heritage: History & Science
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• v.43 no.4
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• pp.56-77
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• 2010

The tortoise pedestal for the memorial monument of Choe Jin-rip(an army officer in the mid-Joseon Period) in Ijo-ri, Naenam-myeon, Gyeongju is known to have been made in 1740. As such, it was originally understood to be a Joseon imitation of a tortoise pedestal made in the Unified Silla Period. The style of the Ijori Tortoise Pedestal differs from other tortoise pedestals dating back to the same period, and bears no resemblance to the Unified Silla pedestals of which it is a copy. Mullu ilgi, a record of the production of the pedestal, explains that the monument was made before the pedestal. Traces show that the two sides of the bottom of the monument were cut off so that it would fit into the smaller space made on the pedestal. It is scarcely conceivable that they made the pedestal and the platform without considering the bottom size of the monument. The record only states that the monument was made at a temple site named Baegundae, without explaining the details of the production process. This leaves some doubt as to whether its production was undertaken systematically. The cloud patterns engraved on this pedestal look similar to the temporal seriation found on the Tortoise Pedestal of the Royal Tomb of King Muyeol and the Seoangni Tortoise Pedestal of Gyeongju. The lotus pattern decorating the square pedestal on the back of the tortoise is one of a number of patterns that were widely used on roof-tiles in the 8th century, the heyday of the Unified Silla Kingdom. The Ijori Tortoise Pedestal, which represents a tortoise moving forward, displays a liveliness the like of which is rarely found in its cousins remaining in Gyeongju. The layout of the patterns in a queue on the tortoise-shell looks much better schematized than those made at an earlier date. It also looks like a more developed form, with the use of space taken into account. Such factors as the style of the patterns, the incongruity between the monument and its pedestal, and what is stated in the historical record indicate that the Ijori Tortoise Pedestal of Gyeongju was made in the mid-8th century(i.e. during the Unified Silla Period), rather than in the Joseon Period(i.e. the 18th century), as an imitation of earlier ones, including changes in the style unique to the Silla Period.