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Appearance Patterns of Freshwater Fish in Central Mountain Area of DMZ, Korea (중부산악 DMZ 민통선이북지역의 담수어류 출현양상)

  • Myung, Ra-Yeon;Seo, Hyung-Soo;Ko, Myeong-Hun
    • Korean Journal of Environment and Ecology
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    • v.34 no.6
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    • pp.530-542
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    • 2020
  • This study surveyed the central mountain area of Demilitarized Zone (DMZ) from March to October 2018 to reveal the appearance patterns of freshwater fish. We collected 7,744 individuals of 43 species in 12 families with skimming nets and cast nets in 12 stations during the survey. The dominant species was Zacco koreanus (30.3%), and the subdominant species was Z. platypus (18.5%), followed by Rhynchocypris oxycephalus (10.0%), R. steindachneri (6.7%), Microphysogobio yaluensis (5.9%), Acheilognathus signifer (4.5%), Pungtungia herzi (4.2%), and Orthrias nudus (2.6%). Among the collected species, four were legally protected. They included Hemibarbus mylodon, which was a natural monument, and Lethenteron reissneri, A. signifer, and Pseudopungtungia tenuicorpa, which were class II endangered wildlife designated by the Ministry of Environment. Twenty Korean endemic species (46.5%) and one exotic species, Micropterus salmoides, were also collected. Additionally, three climate-change sensitive species, R. kumgangensis, Ladislavia taczanowskii, and Cottus koreanus, and three landlocked species, L. reissneri, C. koreanus, and Rhinogobius brunneus appeared. The dominant species in each station were Z. koreanus (15 stations), Z. platypus (four stations), R. oxycephalus (four stations), and C. koreanus (one station). The species dominance index decreased from upstream to downstream (mainstream of Gimhwanamdae Stream), while the species diversity index and the species richness index increased. The community structure of the rivers was divided into the uppermost stream, upper stream, Han River, and Imjin River. Compared to antecedent surveys, this study collected the highest number of species. Two new species (Sarcocheilichthys variegatus wakiyae and Micropterus salmoides) were caught, while six species (Siniperca scherzeri, Leiocassis ussuriensis, Brachymystax lenok tsinlingensis, Rhodeus ocellatus, Abbottina springeri, Aphyocypris chinensis) did not appear. Gimhwanamdaecheon Stream has high biological value with the inhabitation of many species, including species under legal protection and high diversity and richness index scores. This paper also discussed a protection plan for this area.

The Making and Use of the Bifid Ornamental Hairpin Stone Mold Excavated at Neungsan-ri, Buyeo (부여 능산리 출토 가랑비녀 용범(鎔范)의 제작과 사용 양상)

  • LEE, Soleon;KIM, Jiyoung;SEO, Hyunju
    • Korean Journal of Heritage: History & Science
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    • v.54 no.2
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    • pp.4-21
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    • 2021
  • A stone mold from the Sabi period of Baekje was excavated at the western tombs in Neungsan-ri, Buyeo where there was a recent excavation survey (2016). It was believed and reported that such stone molds were used for copper needles during the early Iron Age; however, a close re-examination of the form revealed that they were used for bifid ornamental hairpins. Given its casting form, the stone mold of Neungsan-ri is estimated to have been used to make bifid ornamental hairpins in a ∩ shape, narrowing down toward the tip. It is considered an artifact of the Goryeo dynasty. The stone used to make the bifid ornamental hairpin mold of Neungsan-ri was chlorite-schist, the principal minerals of which include chlorite, amphibole, and talc. Similar rocks are in nearby Buyeo (Oesan-myeon), Cheongyang, Gongju, and Yesan. They are mainly found between Jiseon-ri, Oesan-myeon, Buyeo, Sucheol-ri, Yesane-up, and Yesan. Nearly 70 bifid ornamental hairpins from the Goryeo dynasty were excavated at Neungsan-ri, Buyeo and the surrounding areas. Among them, the bronze ones excavated from the tombs of Songguk-ri, Buyeo are estimated to have been made using this mold as they closely resemble the Neungsan-ri mold. Stone was likely the preferred material for molds to make bronze artifacts as it was easy to sink a die. Regarding the bifid ornamental hairpin cast excavated in Neungsan-ri, they obtained stones in nearby areas 20~50km from their location, made bronze artifacts, and distributed them to nearby sites during the Goryeo dynasty. These artifacts suggest that the casting technology of using a stone mold was still employed then.

Study on the Performer's Transference and Mental Borderline in a Performance (공연에서 나타나는 '전이'와 배우의 '심리적 경계'에 관한 연구)

  • Kim, Jong-Gu
    • (The) Research of the performance art and culture
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    • no.25
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    • pp.57-89
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    • 2012
  • The performers preparing for a performance usually experience the process of mental transference, contacting with text (drama) for the first time. It is movement from their everyday life to space in the play, when they try to break the wall between cast and themselves. The transference happens actually at the physical space, such as a dressing room, wing, (place just before appearing at a stage), and a stage (place to contact with audience). Performers keep moving among each psychological and physical space repeatedly, until the performance finishes totally. The transference means moving to each space to another, and the mental borderline means the point of mental change the performers experience during the process of transference. The mental borderline can be guessed to exist through mental aspects the performers feel when they move from each space to another. The most typical example, that shows performer's mental borderline well, is stage fright shown as tension, or anxiety among the variety of aspects. According to a research, the most performers experience that kind of mental aspect just before appearing at a stage. The study on it is already referred by my article.' A Study on Korean Performer's Stage Fright. This study aims at examining the relationship among psychological and physical space the performers experience, mental borderline when transferring and penetrating those spaces, and performer's mental change First, the concept of mental borderline is to be understood totally with preceded research. And the space the performers experience and mental borderline at transference are to be reorganized. Secondly, the area of transference in the process of performance is to be reclassified into physical and mental space. Third, analyzing the actual case of performers experiencing the mental borderline, the diversified use should be searched to make use of mental borderline as a positive element. The psychological symptoms, performers experience in the performance, can have positive consequence beside negative one. The tension occurring at the area of borderline is positive, and it can be the actual borderline for the performers. It will be researched how the performers change at the mental borderline, the state of mind is maintained, and they perform in an overall performance, through the study on the relationship between the transference and the mental borderline. And the stress and concentration caused by stage fright, and shyness will be confirmed, and the positive element of a stage, which is used as various defense mechanism.

Outcome of Conservative Treatment of the Zone I, II 5th Metatarsal Base Fracture under Early Weight-Bearing (제5 중족골 제1, 2 구역 골절의 조기 체중부하의 비수술적 치료 결과)

  • Gwak, Heui-Chul;Park, Dae-Hyun;Kim, Jung-Han;Lee, Chang-Rack;Kwon, Yong-Uk;Kim, Dong-Seok
    • Journal of the Korean Orthopaedic Association
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    • v.56 no.2
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    • pp.150-156
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    • 2021
  • Purpose: To determine how the location, displacement, intra-articular involvement, comminution of a 5th metatarsal base fracture affect results of early weight-bearing treatment. Materials and Methods: From January 2013 to July 2017, 34 cases of 34 patients diagnosed with a fracture of the zone I and II 5th metatarsal base were enrolled. The mean follow-up period was 13 months (6-15 months). One patient was excluded as a refracture during the follow-up period, and 33 patients underwent conservative treatment. Anteroposterior, lateral, and simple oblique radiography and computed tomography of the foot were performed to evaluate the location and displacement of the fracture, the degree of joint involvement, and comminution. In all 33 patients, a short leg cast or boot brace was selected immediately after the injury, tolerable weight bearing was allowed. If the pain disappeared, full weight bearing was performed after wearing a plain shoe or postoperative shoe. As a clinical result, the American Orthopedic Foot and Ankle Society (AOFAS) score was evaluated at the final follow-up. During outpatient follow-up, a simple radiograph of the foot was taken to confirm the time of radiological bone union and return to work. Results: Nine males and 24 females, with an average age of 48.7 years, were enrolled in the study. Twenty-four patients had zone I fractures, and nine patients had zone II fractures. Twenty-two out of 33 patients had a fracture displacement of 2 mm or more. Nine and five patients had joint involvement and comminution, respectively. There was a statistically significant return to work from zone I to zone II. The AOFAS score was excellent at the final follow-up and there was no significant difference. When classifying and comparing the degree of fracture displacement, joint involvement, and comminution, there were no significant differences in the radiological union time and return to work. In all cases, satisfactory results were obtained at the final follow-up. Conclusion: Satisfactory clinical results can be obtained by allowing early weight-bearing regardless of the fracture location, displacement, joint involvement, or comminution in zone I and II 5th metatarsal base fractures.

The Impact on Fish Assemblage by the River Connectivity Fragmentation: Case Study of the Danjang Stream, South Korea (하천 연속성 단절이 어류상에 미치는 영향: 밀양 단장천을 중심으로)

  • Seung-Been Heo;Kang-Hui Kim;Donghyun Hong;Hyeon-Sik Lee;Gu-Yeon Kim;Gea-Jae Joo;Hyunbin Jo
    • Korean Journal of Ecology and Environment
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    • v.55 no.3
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    • pp.231-243
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    • 2022
  • Anthropogenic disturbances on freshwater ecosystem are known to degrade biodiversity, especially on fish assemblage. In this study, we have conducted fish surveys to identify impact of a bridge construction on fish assemblages. A total of eight study sites were surveyed in the Danjang and the Dong Stream in southern part of South Korea from June to November in 2021. The fish samplings were carried out five times, using cast-nets(10×10 mm mesh size), scoop-nets(4×4 mm, 5×5 mm mesh size), set-nets (10×10 mm mesh size), and fish traps (3×3 mm mesh size), along with the Stream/River Ecosystem Survey and Health Assessment by the Ministry of Environment of Korea and basic water quality measurement. Also, we applied the species diversity index and length-weight relationship regressions on certain species to identify interspecific growth rate differences in accordance with study sites. As a result, a total of 782 individuals, 23 species and 10 families were collected. The dominant species was Zacco Koreanus and relative abundance was 50.89%. When applying the length-weight relationship regressions on certain species, the 'b' value for Z. Koreanus was lower at the downstream points than at the upstream points of the construction site. In addition, when comparing to the results of the past survey, relative density of demersal fish at the upstream and downstream points decreased from 26% to 1.4%, and from 18% to 6.3%, respectively. In conclusion, it is considered that bridge construction negatively affects the habitat of fishes, especially on demersal fishes. Therefore, appropriate conservation efforts such as installation of silt protector and sand sedimentation pond are needed to alleviate the disturbance in habitat such as occurrence of turbidity and destruction of micro-habitats.

A Review of the Influence of Sulfate and Sulfide on the Deep Geological Disposal of High-level Radioactive Waste (고준위방사성폐기물 심층처분에 미치는 황산염과 황화물의 영향에 대한 고찰)

  • Jin-Seok Kim;Seung Yeop Lee;Sang-Ho Lee;Jang-Soon Kwon
    • Economic and Environmental Geology
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    • v.56 no.4
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    • pp.421-433
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    • 2023
  • The final disposal of spent nuclear fuel(SNF) from nuclear power plants takes place in a deep geological repository. The metal canister encasing the SNF is made of cast iron and copper, and is engineered to effectively isolate radioactive isotopes for a long period of time. The SNF is further shielded by a multi-barrier disposal system comprising both engineering and natural barriers. The deep disposal environment gradually changes to an anaerobic reducing environment. In this environment, sulfide is one of the most probable substances to induce corrosion of copper canister. Stress-corrosion cracking(SCC) triggered by sulfide can carry substantial implications for the integrity of the copper canister, potentially posing a significant threat to the long-term safety of the deep disposal repository. Sulfate can exist in various forms within the deep disposal environment or be introduced from the geosphere. Sulfate has the potential to be transformed into sulfide by sulfate-reducing bacteria(SRB), and this converted sulfide can contribute to the corrosion of the copper canister. Bentonite, which is considered as a potential material for buffering and backfilling, contains oxidized sulfate minerals such as gypsum(CaSO4). If there is sufficient space for microorganisms to thrive in the deep disposal environment and if electron donors such as organic carbon are adequately supplied, sulfate can be converted to sulfide through microbial activity. However, the majority of the sulfides generated in the deep disposal system or introduced from the geosphere will be intercepted by the buffer, with only a small amount reaching the metal canister. Pyrite, one of the potential sulfide minerals present in the deep disposal environment, can generate sulfates during the dissolution process, thereby contributing to the corrosion of the copper canister. However, the quantity of oxidation byproducts from pyrite is anticipated to be minimal due to its extremely low solubility. Moreover, the migration of these oxidized byproducts to the metal canister will be restricted by the low hydraulic conductivity of saturated bentonite. We have comprehensively analyzed and summarized key research cases related to the presence of sulfates, reduction processes, and the formation and behavior characteristics of sulfides and pyrite in the deep disposal environment. Our objective was to gain an understanding of the impact of sulfates and sulfides on the long-term safety of high-level radioactive waste disposal repository.

Effect of Solution Treatment Conditions on the Microstructure and Hardness Changes of Al-7Si-(0.3~0.5)Mg-(0~0.5)Cu Alloys (Al-7Si-(0.3~0.5)Mg-(0~0.5)Cu 합금의 미세조직 및 경도 변화에 미치는 용체화 처리 조건의 영향)

  • Sung-Bean Chung;Min-Su Kim;Dae-Up Kim;Sung-Kil Hong
    • Journal of Korea Foundry Society
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    • v.42 no.6
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    • pp.337-346
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    • 2022
  • In order to optimize the solution treatment conditions of Al-7Si-(0.3~0.5)Mg-(0~0.5)Cu alloys, a series of heat treatment experiments were conducted under various solution treatment times up to 7 hours at 545℃, followed by a microstructural analysis using optical microscopy, FE-SEM, and Brinell hardness measurements. Rapid coarsening of eutectic Si particles was observed in the alloys during the first 3 hours of solution treatment but the size of those Si particles did not change at longer solution treatment conditions. Meanwhile, the degree of spheroidisation of eutectic Si particles increased until the solution treatment time was increased up to 7 hours. Q-Al5Cu2Mg8Si6 andθ-Al2Cu were observed in as-cast Cu-containing Al alloys but the intermetallic compounds were dissolved completely after 3 hours of solution treatment at 545℃. Depending on the initial Mg composition of the Al alloys, π-Al8FeMg3Si either disappeared in the alloy with 0.3wt% of Mg content after 5 hours of solution treatment or remained in the alloy with 0.5wt% of Mg content after 7 hours of solution treatment time. Mg and Cu content in the primary-α phase of the Al alloys increased until the solution treatment time reached 5 hours, which was in accordance with the dissolution behavior of Mg or Cu-containing intermetallic compounds with respect to the solution treatment time. From the results of microstructural changes in the Al-7Si-Mg-Cu alloys during solution treatment, it was concluded that at least 5 hours of solution treatment at 545℃ is required to maximize the age hardening effect of the present Al alloys. The same optimal solution treatment conditions could also be derived from Brinell hardness values of the present Al-7Si-Mg-Cu alloys measured at different solution treatment conditions.

Coniunctio Oppositorum in Korean Fairytale - <Gurungdungdung Sin Seonbi> - (한국 민담에 나타난 대극의 합일 - <구렁덩덩 신 선비> 중심으로 -)

  • Youkyeng Lee
    • Sim-seong Yeon-gu
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    • v.27 no.1_2
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    • pp.1-27
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    • 2012
  • It aims to deal with a topic of coniunctio oppositorum, hieros gamos in a Korean fairytale <Gurungdungdung Sin Seonbi>, in which a human heroine was marrying an animal husband. This Korean fairytale may be compared with Greek mythology <Eros and Psyche> introduced by Apuleius and <Dassingende springende Löweneckerchen> collected by Grimm Brothers. All these fairytales commonly tell that animal husband figures have divine nature. Because animals live their lives totally obeying instincts, the collective unconscious principles of species are completely accomplished. The animal nature excludes ecocentric attitude so that it has transpersonal divinity. The hero is transformed into an animal in the fairytales, which will provide an opportunity to change a one-sided exaggerated attitude of the ego consciousness and acquire universal humanity. During being an animal, the hero would have experienceds to recognize true meaning and value of other living creatures in nature and have attained wisdom of nature. The animal is a symbolic being who will realize value of collective and universal life so as to act therapeutically and contribute to the total personality, individuation processes. Animals in the fairytales correspond to the compensatory contents of the unconscious. Animal figure itself is opposite to the ego consciousness itself because the ego understands the unconscious contents like animal figures have instinctual impulse that the ego will not accept at all. Coniunctio oppositorum in the fairytales is going to show the ego's rendezvous processes to meet the unconscious. The fact that the hero turns into an animal or marries animal partner is a psychic event which greatly lowers under the level of ego consciousness. To overcome the state, it is essential for the hero to regain humanity or to transform animal partner into a human being. By the recovery of humanity or reaching the human level, compensation of the unconscious can be realized in the conscious life. In a Korean fairytale <Gurungdungdung Sin Seonbi>, male partner is a serpent but the heroine marries the serpent and make it cast off skin. Over sufferings and complishment of several tasks, heroine truly meets her husband. In this processes, the heroine obtains divinity. As result, her marriage to animal husband means hieros gamos. In this fairytale, we will be able to look through the ways how female ego-consciousness to make relations to the unconscious and to fulfill individuation.

Reexamination of Ancient Ironmaking Technology Restoration Experiment Operating Methods (고대 제철기술 복원실험 조업방식에 대한 재검토 - 국립중원문화유산연구소 1~8차 복원실험을 중심으로 -)

  • CHOI Yeongmin;JEONG Gyeonghwa
    • Korean Journal of Heritage: History & Science
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    • v.57 no.2
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    • pp.6-25
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    • 2024
  • This study concentrated on a report on the results of smelting experiments conducted eight times by the Jungwon National Research Institute of Cultural Heritage, put together the goals and results of the operation, and examined changes in the content of experiments and in the experimental results. First, changes related to operation, such as the ratio of raw materials to fuel and the presence or absence of additives, were reviewed depending on the operation goal. In addition, the results of metallurgical analysis of raw materials, formations, and byproducts were summarized and reviewed by comparing them with materials excavated from the ruins. The operation method varied up to the eighth smelting experiment in terms of iron ore roasting, additives, and raw material/fuel ratio. After reviewing the results again, pure iron with a low carbon content began to be confirmed through metallurgical analysis. As a result, it was confirmed that the charging ratio of raw materials and fuel plays an important role depending on the purpose of production. In addition, most of the products are gray cast iron, and it was deemed that this is due to changes in the internal structure of the pig iron while it was left in the furnace for a long time. The iron was an ingot that was in a molten state even though the carbon content did not reach 4.3%, where the process reaction takes place, and it was deemed to have been caused by excessive operating temperature. Based on the previously reviewed results and the structure and shape of the experimental furnace used in other ironmaking technology restoration experiments, this study finally attempted to restore the structure of an ancient iron smelting furnace, including the furnace's upper structure. By comprehensively referring to the remaining conditions of the excavated iron smelting furnace and the characteristics of the blow pipe, the form of the ancient iron smelting furnace was subdivided into six categories: furnace wall thickness, furnace height, blower height, blow pipe size, furnace inner wall shape, and top shape, and a restoration plan was proposed. To improve the problems of the restoration plan and the Jungwon National Research Institute of Cultural Heritage's experiments that have been conducted through continuous trial and error, an experiment that reflects changes in operating methods by lowering the furnace height and controlling the blowing volume is necessary.

The Establishment and Development of Wooden Coffin Tombs in the Jinhan and Byeonhan Confederacies: An Examination of the Wolseong-dong Type (진·변한 목관묘 문화의 성립과 전개 -월성동 유형의 검토와 함께)

  • Lee Donggwan
    • Bangmulgwan gwa yeongu (The National Museum of Korea Journal)
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    • v.1
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    • pp.150-173
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    • 2024
  • The Gyeongsang region experienced an epoch-making social transformation approximately around the second to first century BCE, including the replacement of Bronze Age types of tombs (such as dolmens, stone cist tombs, and earthen tombs with flat capstones) with clusters of wooden coffin tombs and the emergence of wajil pottery (soft stoneware) and ironware. These shifts in the archaeological material evidence have been discussed in the context of the formation of the states that comprised the three Han confederacies and in relation to wooden coffin tombs built in later periods. This paper explicates the appearance of clustered wooden coffin tombs with accompanying ironware by categorizing them. In particular, it examines the emergence of wooden coffin tombs by creating the Wolseong-dong type, which differs from Tomb No. 5 in Joyang-dong and Tomb No. 1 in Daho-ri with their deep burial pits and large quantities of prestige goods and soft stoneware items. The Wolseong-dong type of tomb commonly features ironware, including flat-bladed iron axes, oblong cast iron axes, iron wire, iron chisels, and iron swords; a small slender, rectangular wooden coffin tomb with a shallow burial pit of less than sixty centimeters; and pottery of a type preceding soft stoneware, such as long-necked jars, triangular attached-rim pottery bowls and pots, and mounted vessels. There are also a few bronzeware items found in them, but no prestige goods. This study scrutinizes tombs in Tamni-ri in Uiseong, Hagu-ri in Gyeongju, and Hakjeongdong in Daegu by comparing them with the Wolseong-dong type, and it confirms that in Sinseodong in Daegu, Wolseong-dong type tombs and later Joyang-dong type tombs have separate spatial distributions within the site. This also indicates that the Wolseong-dong type is a valid categorization among wooden coffin tombs. Although the rise of the Wolseong-dong type tomb is associated with the migration of a group, I reserve judgement on whether its origins should be understood in the context of the iron culture in the southwestern region of South Korea that was sparked by King Jun's advance to the south or if they lie in the western region of North Korea. Either way, the Wolseong-dong type is thought to be the tombs of a group of people with lower hierarchical status than the occupants of the later Joyang-dong type.