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Provenance of the ARA07C-St02B Core Sediment from the East Siberian Margin (동시베리아해 연변부 ARA07C-St02B 코어 퇴적물의 기원지 연구)

  • Koo, Hyo Jin;Lim, Gi Taek;Cho, Hyen Goo
    • Korean Journal of Mineralogy and Petrology
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    • v.35 no.1
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    • pp.13-24
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    • 2022
  • The Arctic Ocean is very sensitive to global warming and Arctic Ocean sediments provide a records of terrestrial climate change, analyzing their composition helps clarify global warming. The gravity core sediment ARA07C-St02B was collected at the East Siberian margin during an Arctic expedition in 2016 on the Korean ice-breaking vessel ARAON, and its provenance was estimated through sedimentological, mineralogical and geochemical analysis. The core sediment was divided into four units based on sediment color, sand content and ice-rafted debris content. Units 1 and 3 had higher sand and ice-rafted debris contents than units 2 and 4, and contained a brown layer, whereas units 2 and 4 were mainly composed of a gray layer. Correlation analysis using the adjacent core sediment ARA03B-27 suggested that the sediment units were deposited during marine isotope stage 1 to 4. The bulk mineral, clay mineral, and geochemical compositions of units including a brown layer differed from units including a gray layer. Bulk and clay mineral compositions indicated that coarse and fine sediments had a different origin. Coarse sediments might have been deposited mostly by the East Siberian Coastal Current from the Laptev Sea and the East Siberian Sea or by the Beaufort Gyre from the Chukchi Sea, whereas fine sediments might have been transpoted mostly by currents from the East Siberian Sea, the Chukchi Sea and the Beaufort Sea. Some of the coarse sediments in unit 1 and fine sediments in unit 3 might have been deposited by iceberg ice, sea ice or current from the Beaufort Sea and the Canada Archipelago. Investigating the geochemical composition of the potential origins will elucidate the origin and transportation of the study area's core sediments.

Experimental Study on the Agglomeration Characteristics of Coal and Silica Sand by addition of KOH (KOH 첨가에 의한 석탄 및 유동사의 응집특성에 대한 실험적 연구)

  • Cho, Cheonhyeon;Gil, Eunji;Lee, Uendo;Lee, Yongwoon;Kim, Seongil;Yang, Won;Moon, Jihwan;Ahn, Seokgi;Jung, Sungmook;Jeong, Soohwa
    • Clean Technology
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    • v.28 no.1
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    • pp.46-53
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    • 2022
  • The agglomeration characteristics of coal and silica sand were investigated under various conditions using mixed samples consisting of coal, silica sand, and potassium hydroxide, which is an agglomeration accelerator. The samples were prepared by either physically mixing or using aqueous solutions. The experiments using the physically mixed powder samples were performed with a two hour reaction time. The results showed that the number of aggregates generated increased as the reaction temperature and the total potassium content increased. The experiments using aqueous solutions were performed at 880 ℃, which is the operating temperature of a fluidized bed boiler, and at 980 ℃, which assumes a local hot spot. The amount of agglomeration generated as the reaction time increased and the total potassium content increased was identified. In the experiment performed at 880 ℃, the amount of aggregate generated clearly increased with the reaction time, and in the experiment performed at 980 ℃, assuming a local hot spot, a large amount of aggregate was generated in a relatively short time. The aggregates became harder as the potassium content increased. When the total potassium content was less than 1.37 wt.%, the aggregates were weak at both temperatures and collapsed even with a slight impact. Additionally, the surface characteristics of the silica sand and ash aggregates were observed by SEM-EDS analysis. The analysis revealed a large amount of potassium at the bonding sites. This result indicates that there is a high possibility of aggregation in the form of a eutectic compound when the alkali component is increased.

Characteristics of the construction process, the history of use and performed rituals of Gyeongungung Heungdeokjeon (경운궁 흥덕전의 조영 및 사용 연혁과 설행된 의례의 특징)

  • LIM, Cholong;JOO, Sanghun
    • Korean Journal of Heritage: History & Science
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    • v.55 no.1
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    • pp.281-304
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    • 2022
  • Heungdeokjeon was the first pavilion built on the site of Sueocheong during the expansion of Gyeongungung. In this study, we tried to clarify the specific construction process of Heungdeokjeon, which was used for various purposes such as the copy location for Portraits of ancestors, temporary enshrinement site, and the funeral building for the rest of the body, which is Binjeon. In addition, we tried to confirm the historical value based on the characteristics derived by the history of the building and the rituals performed. Heungdeokjeon began to be built in the second half of 1899, and is estimated to have been completed between mid-February and mid-March 1900. It was a ritual facility equipped with waiting rooms for the emperor and royal ladies as an annex. The relocation work was planned in April 1901 and began in earnest after June, and it was closely linked to the construction of attached buildings of Seonwonjeon. In addition, comparing the records on the construction and relocation cost of Heungdeokjeon with those related to the reconstruction of Seonwonjeon, it was confirmed that annex buildings of Heungdeokjeon were relocated and used as annex buildings of Seonwonjeon. The characteristics identified in the process of Heungdeokjeon used as a place to copy portraits are as follows. First, it was used as a place to copy portraits twice in a short period of time. Second, it was the place where the first unprecedented works were carried out in relation to the copying of portraits. Third, the pavilion, which was specially built for imperial rituals, was used as a place to copy portraits. Since then, it has been used as a funeral building for the rest of the body, and features different from those of the previous period are identified. It was the building dedicated to rituals for use as Binjeon, and was also a multipurpose building for copying portraits. In other words, Heungdeokjeon, along with Gyeongbokgung Taewonjeon, is the building that shows the changes in the operation of Binjeon in the late Joseon Dynasty. Characteristics are also confirmed in portrait-related rituals performed at Heungdeokjeon. The first is that Jakheonlye was practiced frequently in a short period of time. The second is that the ancestral rites of Sokjeolje and Bunhyang in Sakmangil, which are mainly held in the provincial Jinjeon, were identified. This is a very rare case in Jinjeon of the palace. The last is that Jeonbae, jeonal, and Bongsim were implemented mutiple times. In conclusion, Heungdeokjeon can be said to be a very symbolic building that shows the intention of Gojong, who valued imperial rituals, and the characteristics of the reconstruction process of Gyeongungung.

The Alterations of Geochemical Behavior of Arsenic in Stabilized Soil by the Addition of Phosphate Fertilizer (인산질 비료에 의한 안정화 적용 토양 내 비소의 지구화학적 거동 변화)

  • Jeon, Yong-Jung;Kim, Bun-Jun;Ko, Ju-In;Ko, Myoung-Soo
    • Economic and Environmental Geology
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    • v.55 no.2
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    • pp.209-217
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    • 2022
  • The purpose of this study was to confirm the dissolution of arsenic from the stabilized soil around abandoned coal mines by cultivation activities. Experimental soils were collected from the agricultural field around Okdong and Buguk coal mines, and the concentration of arsenic in the soil and the geochemical mobility were confirmed. The average arsenic concentration was 20 mg/kg. The soil with relatively high geochemical mobility of arsenic in the soil was used in the batch and column experiment. The limestone was mixed with soil for soil stabilization, and the mixing ratio was 3% of limestone, based on the soil weight. The phosphoric acid fertilizer (NH4H2PO4) was added to the soil to simulate a cultivation condition according to the Rural Development Administration's rules. Comparative soil without mixing limestone was prepared and used as a control group. The arsenic extraction from soil was increased following the fertilizer mixing amount and it shows a positive relationship. The concentration of phosphate in the supernatant was relatively low under the condition of mixing limestone, which is determined to be result of binding precipitation of phosphate ions and calcium ions dissolved in limestone. Columns were set to mix phosphoric acid fertilizers and limestone corresponding to cultivation and stabilization conditions, and then the column test was conducted. The variations of arsenic extraction from the soil indicated that the stabilization was effectible until 10 P.V.; however, the stabilization effect of limestone decreased with time. Moreover, the geochemical mobility of arsenic has transformed by increasing the mobile fractions in soil compared to initial soil. Therefore, based on the arsenic extraction results, the cultivation activities using phosphoric fertilizer could induce a decrease in the stabilization effect.

Manufacture of non-sintered cement solidifier using clay, waste soil and blast furnace slag as solidifying agents: Mineralogical investigation (점토, 폐토양 및 고로슬래그를 고화재로 이용한 비소성 시멘트 고화체 제조: 광물학적 고찰)

  • Jeon, Ji-Hun;Lee, Jong-Hwan;Lee, Woo-Chun;Lee, Sang-Woo;Kim, Soon-Oh
    • Korean Journal of Mineralogy and Petrology
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    • v.35 no.1
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    • pp.25-39
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    • 2022
  • This study was conducted to evaluate the manufacturing process of non-sintered cement for the safe containment of radioactive waste using low level or ultra-low level radioactive waste soil generated from nuclear-decommissioning facilities, clay minerals, and blast furnace slag (BFS) as an industrial by-product recycling and to characterize the products using mineralogical and morphological analyses. A stepwise approach was used: (1) measuring properties of source materials (reactants), such as waste soil, clay minerals, and BFS, (2) manufacturing the non-sintered cement for the containment of radioactive waste using source materials and deducing the optimal mixing ratio of solidifying and adjusting agents, and (3) conducting mineralogical and morphological analyses of products from the hydration reactions of manufactured non-sintered cement solidifier (NSCS) containing waste concrete generated from nuclear-decommissioning facilities. The analytical results of NSCS using waste soil and clay minerals confirmed none of the hydration products, but calcium silicate (CSH) and ettringite were examined as hydration products in the case of using BFS. The compressive strength of NSCS manufactured with the optimum mixing ratio and using waste soil and clay minerals was 3 MPa after the 28-day curing period, and it was not satisfied with the acceptance criteria (3.44 MPa) for being brought in disposal sites. However, the compressive strength of NSCS using BFS was estimated to be satisfied with the acceptance criteria, despite manufacturing conditions, and it was maximized to 27 MPa at the optimal mixing ratio. The results indicate that the most relevant NSCS for the safe containment of radioactive waste can be manufactured using BFS as solidifying agent and using waste soil and clay minerals as adsorbents for radioactive nuclides.

A Study on the Origin of Image-Number Theory in Cho Hoik's Yixiangshuo (조호익(曺好益) 『역상설(易象說)』의 상수학적 연원)

  • Im, Jae-kyu
    • Journal of the Daesoon Academy of Sciences
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    • v.38
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    • pp.183-208
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    • 2021
  • In order to examine the origin of Image-Number Theory in Cho Hoik (曺好益)'s Yixiangshuo (易象說), it is necessary to review Hu Yigui (胡一桂)'s Zhouyi Benyi Fulu Zuanzhu (周易本義附録纂注). Hu Yigui based his work on Zhu Xi's Zhouyi Benyi, he took related contents such as the Zhu Xi's writings and phrases and organized them into a fulu (附録), and he collected commentaries that matched the meaning of Zhouyi Benyi among the theories of many Confucian scholars and produced a zuanzhu (纂注). In addition to these, there are 'Yuwei (愚謂)' and 'Yuan (愚案)' which allowed him to add his own opinion. The system of Hu Yigui's Zhouyi Benyi Fulu Zuanzhu almost coincides with Cho Hoik's Yi-ological writing system. In other words, Cho Hoik appears to have written Yizhuan Bianjie (易傳辨解) and Zhouyi Shijie (周易釋解) as a fulu and zuanzhu of Zhouyi Benyi Fulu Zuanzhu. And there is Yixiangshuo which corresponds to 'Yuwei' and 'Yuan' of Zhouyi Benyi Fulu Zuanzhu. Yixiangshuo was not originally an independent Yi-ological book, but was compiled by later generations from what was recorded in the form of the head notes of Zhouyi (周易). Thus, Yixiangshuo takes almost the same form as the 'Yuwei' and 'Yuan' of Zhouyi Benyi Fulu Zuanzhu. In addition, Cho Hoik's Yixiangshuo cites many contents from 'Yuwei' and 'Yuan' of Zhouyi Benyi Fulu Zuanzhu. On the other hand, in order to examine the origin of Image-Number Theory in Cho Hoik's Yixiangshuo, the Yi-ology of Zhu Zhen (朱震) cannot be overlooked. This is true not only due to the fact that Yixiangshuo is quoting Zhu Zhen. The more significant reason is Yixiangshuo is a fundamental aspect of Zhu Zhen's Yi-ology. As demonstrated in the main body of this article, the methodology of Image-Number Theory in Yixiangshuo and its counterpart in Hanshang Yizhuan (漢上易傳) are almost identical. In conclusion, the origin of Image-Number Theory in Cho Hoik's Yixiangshuo can be found in both the Hu Yigui's Zhouyi Benyi Fulu Zuanzhu and Zhu Zhen's Hanshang Yizhuan. In particular, it can be said that its origin can be found in both the 'Yuwei' and 'Yuan' of Zhouyi Benyi Fulu Zuanzhu and the methodlogy of Image-Number Theory in Hanshang Yizhuan.

Manufacturing Techniques of Bronze Medium Mortars(Jungwangu, 中碗口) in Joseon Dynasty (조선시대 중완구의 제작 기술)

  • Huh, Ilkwon;Kim, Haesol
    • Conservation Science in Museum
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    • v.26
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    • pp.161-182
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    • 2021
  • A jungwangu, a type of medium-sized mortar, is a firearm with a barrel and a bowl-shaped projectileloading component. A bigyeokjincheonroe (bombshell) or a danseok (stone ball) could be used as a projectile. According to the Hwaposik eonhae (Korean Translation of the Method of Production and Use of Artillery, 1635) by Yi Seo, mortars were classified into four types according to its size: large, medium, small, or extra-small. A total of three mortars from the Joseon period have survived, including one large mortar (Treasure No. 857) and two medium versions (Treasure Nos. 858 and 859). In this study, the production method for medium mortars was investigated based on scientific analysis of the two extant medium mortars, respectively housed in the Jinju National Museum (Treasure No. 858) and the Korea Naval Academy Museum (Treasure No. 859). Since only two medium mortars remain in Korea, detailed specifications were compared between them based on precise 3D scanning information of the items, and the measurements were compared with the figures in relevant records from the period. According to the investigation, the two mortars showed only a minute difference in overall size but their weight differed by 5,507 grams. In particular, the location of the wick hole and the length of the handle were distinct. The extant medium mortars are highly similar to the specifications listed in the Hwaposik eonhae. The composition of the medium mortars was analyzed and compared with other bronze gunpowder weapons. The surface composition analysis showed that the medium mortars were made of a ternary alloy of Cu-Sn-Pb with average respective proportions of (wt%) 85.24, 10.16, and 2.98. The material composition of the medium mortars was very similar to the average composition of the small gun from the Joseon period analyzed in previous research. It also showed a similarity with that of bronze gun-metal from medieval Europe. The casting technique was investigated based on a casting defect on the surface and the CT image. Judging by the mold line on the side, it appears that they were made in a piece-mold wherein the mold was halved and using a vertical design with molten metal poured through the end of the chamber and the muzzle was at the bottom. Chaplets, an auxiliary device that fixed the mold and the core to the barrel wall, were identified, which may have been applied to maintain the uniformity of the barrel wall. While the two medium mortars (Treasure Nos. 858 and 859) are highly similar to each other in appearance, considering the difference in the arrangement of the chaplets between the two items it is likely that a different mold design was used for each item.

A Study on the Deok and Its Practice in Daesoon Thought: The Great Deok of Heaven and Earth of Kang Jeungsan (대순사상에 나타난 덕(德)과 그 실천수행 -강증산의 '천지대덕(天地大德)'과 관련하여-)

  • Joo, So-yeon;Ko, Nam-sik
    • Journal of the Daesoon Academy of Sciences
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    • v.38
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    • pp.1-46
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    • 2021
  • Since ancient times, the word Deok (德, virtue) has been used as a term in ethics. In the east, it originally meant 'to acquire (得),' and during the warring states period, it was used to indicate 'personality' or 'value;' especially for political leaders. Then, in Confucianism, the word Deok developed into an ethical term suggesting that people should acquire Deok in their action so as to achieve human perfection. In Daesoon Thought, Deok originates from the Dao, and the two are close in the same manner that Yin and Yang are close and interrelated. The Dao of Daesoon Thought indicates the Great Dao of Heaven and Earth, which Gucheon Sangje had opened when he performed his Gongbu (holy work) at Daewonsa Temple, is such that the Great Deok was divided into the Deok of Heaven, the Deok of Earth, and the Deok of Humanity. This allows for the realization of Deok in each of the Three Realms. Jo Jeongsan, the successor of Gucheon Sangje, said that he will inherit the Great Deok originated from the Great Dao and enlighten the world to the Dao. The cause of the accumulation of grievances in the Three Realms was due to the failure to sufficiently spread Deok throughout the Three Realms. The Later World is where Deok will be offered in its full extent as it was secured by the Cheonjigongsa (Reordering Works of Heaven and Earth) performed by Gucheon Sangje. However, as the main agent of spreading Deok is the heart-mind, humans need to cultivate their heart-mind in the correct way. When humans finally become Dotong-gunja (beings who are perfectly unified with the Dao) and generously practice Deok in the world, there will be no grievances anywhere in the Three Realms. There are four ways of practicing Deok: Deok by caring for life, Eondeok (Deok of speech), Gongdeok (practicing meritorious Deok), and Podeok (spreading of Deok) to the world. Practicing the Deok by caring for life is to save and protect living beings based on the spirit of Jesaenguise (saving lives and curing the world). Eondeok is practiced when people speak to others in a positive way that fosters widespread goodness based on the spirit of Sangsaeng (mutual beneficence). When people perform Gongdeok they will be rewarded for their actions. Podeok can be realized when the followers of Sangje spread the Great Dao of Heaven and Earth based on the teachings of Daesoon Thought.

Study of the Production Techniques Used in the Goryeo-period Gilt-Bronze Case for Acupuncture in the Collection of the Royal Museums of Art and History, Belgium (벨기에 왕립예술역사박물관 소장 고려시대 금동침통의 과학적 보존처리를 통한 제작기법 연구)

  • Lee, Jaesung;Park, Younghwan
    • Conservation Science in Museum
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    • v.27
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    • pp.147-164
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    • 2022
  • Over 200,000 Korean cultural heritage items are currently located abroad. They have made their way to 22 countries under different circumstances and with unique backgrounds. While some of them continue to contribute to promoting Korean culture around the world, others cannot be exhibited due to damage or poor condition. In view of these circumstances, the Overseas Korean Cultural Heritage Foundation (OKCHF) has since 2013 provided museums and art galleries abroad with support for the conservation, restoration, and utilization of the Korean cultural heritage items that they house. As a part of these efforts and on the occasion of the 120th anniversary of the diplomatic relationship between the Republic of Korea and the Kingdom of Belgium in 2021, a gilt-bronze case for acupuncture needles dating to the Goryeo period (918-1392) from the collection of the Royal Museums of Art and History (RMAH), Belgium was brought to Korea for conservation treatment. The primary purpose of this conservation treatment was to restore the original form of the relic and slow to the degree possible the progress of corrosion. The conservation treatment of the gilt-bronze case followed the fundamental order of conservation treatment: removal of corrosive substances, stabilization, and reinforcement. Since this was the first case of restoring metallic cultural properties under the abovementioned support program by the OKCHF, special methodologies distinct from those available in overseas institutions were required. Diverse scientific methods (e.g., X-ray inspection, CT scanning, 3D microscopy) were applied to identify the metalcraft techniques used in the Goryeo period. The analysis found that several designs, including lotus and scrollwork, were exquisitely engraved on the surface of the case by making dots using a round-edged chisel. A bronze plate engraved with designs was rolled into a cylindrical form. The ends were overlapped by 2 to 3 centimeters and then attached to each other by silver soldering. The overlapping ends were welded flat with nearly no gaps. As the final process in the production, the case was lavishly gilt with gold powder using amalgam gilding. The conservation treatment of the gilt-bronze case for acupunctural needles in the RMAH collection restored the original form of the relic and arrested further corrosion. Above all, it revived the historic and academic value of the overseas Korean cultural heritage through scientific analysis.

Choi Chi-won, the Originator of Jeongeup Museongseowon and Scholar Culture (정읍 무성서원과 선비문화 원류 최치원)

  • An, Young-hoon
    • Journal of the Daesoon Academy of Sciences
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    • v.40
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    • pp.243-272
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    • 2022
  • Jeongeup, Jeollabuk-do, is an area that requires attention from those who study the history of Korean thought. In addition, Jeongeup is an area wherein many works were recorded for the first time in literary history. This is the case with Jeongeupsa as a style of Baekje songs and the lyrics of the noble families of the Joseon Dynasty, Sangchungok. Jeongeup is likewise the location where Choi Chi-won (857~?) was selected to serve as a local taesu (viceroy) and where a unique tradition of music and style were passed down. In this paper, the relationship between Choi Chi-won's role in the process of establishing a silent Confucian academy in Jeongeup and the emergence of scholar culture was examined. When Choi Chi-won left after his term in office, a birth shrine called Taesansa Temple was built to repay the selection of the villagers, and it became the source that led to the opening of the Confucian academy Museongseowon in the future. Jeongeup will be shown to be the location where Choi Chi-won realized his aspirations and honed his capabilities. In particular, Choi Chi-won's played a crucial role in the mid-Joseon Dynasty by supporting the construction and securing the name of Museongseowon. That is why Choi Chi-won was able to be revived as a symbolic figure in the region. In addition, it can be seen that the shape of Choi Chi-won was more sedentary- in the form of a Confucian scholar- and Confucian scholars emphasized the transfer of portraits at Museongseowon. Through the poetry written by Choi Chi-won, readers can learn about the worries and perceptions of scholars during those times. Although his value in the field of poetry is diverse, he can especially be recognized as a Confucian intellectual. In a large number of his works, he expresses his anxiety, agony, and critical inner consciousness all of which came from his encounter with the realities of his time. In fact, Choi Chi-won showed his qualities as a prominent literary figure of his time who had extraordinary aspirations and an admirable work ethic. However, he failed to overcome his regional and mental alienation as a poet in neighboring countries. Therefore, he internalized a sort of fierceness in terms of his perception of the world. However, it seems that it was rather a factor that made his work exhibit a strong lyrical style. In addition, Choi Chi-won's collection of writings includes a number of works that strongly criticized various forms of pathological phenomena caused by terminal phenomena of the time. He also highlighted the wrong in society by realistically depicting the lives poor and needy people and their eventual sacrifice via distorted relationships. This can be read encapsulating the agony of intellectuals of that time. The dictionary definition of a 'Confucian scholar' is "a Confucian term referring to a person or class that embodies Confucian ideology," and in its contemporary meaning it suggests " ⋯ an example of a personality, but not an identity, and the conscience of one's time period as a source of human morality inwardly and social order outwardly." In this respect, it could even be said that Choi Chi-won could be considered the originator of scholar culture.