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Feasibility Study on Technology Status Level and Location Conditions of Urban Mining Industry in Abandoned Mine Area (도시광산 산업의 현황수준 및 폐광지역 입지여건 타당성 연구)

  • Ko, Ilwon;Park, Joo-Hyun;Park, Jae-Hyun;Yang, In-Jae;Lee, Seung-Ae;Kim, Dae-Yeop;Kim, Su-Ro
    • Journal of the Korean Society of Mineral and Energy Resources Engineers
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    • v.55 no.6
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    • pp.553-563
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    • 2018
  • In this study, the location conditions and optimal technologies required for creating urban municipalities that can utilize the space in an abandoned mine area, where there is no infrastructure related to recycling wastes and valuable metals, are investigated. The urban mining industry deals with mineral resources through the processing of high value-added industrial by-products and wastes, and it is a useful linkage industry for the development of mineral resources and prevention of mining hazards. Urban mining technologies targeted at the abandoned mine area constitute screening, extraction, and smelting for recycling waste products. By analyzing the technologies available, an industrial network can be developed for recycling waste batteries and catalysts, which are promising raw materials. It is also important to establish an appropriate location for related industries that can generate value-added resources, rather than the resource supply and demand conditions seen in general urban mines. In order to overcome the accessibility and infrastructure limitations, the economic foundation of the abandoned mine area should consider the linkage of raw material supply, key technologies for recycling useful mineral resources that are derived from urban mines, spatial and site conditions, and industrial characteristics.

Biosynthesis of Compound K, a biologically active saponin of ginseng(Panax ginseng) by bioconversion (인삼(Panax ginseng)으로부터 생물전환을 이용한 생리활성물질인 Compound K의 생합성)

  • Kim, MooSung;Kim, Ja-i;Jung, Kyung-Hwan;Yu, Kwang-Won;Moon, Gi-Seong;Lee, Hyang-Yeol
    • Journal of the Korean Applied Science and Technology
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    • v.38 no.5
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    • pp.1335-1344
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    • 2021
  • Ginsenoside Compound K is a triterpene saponin found in the leafs, stems and roots of Panax ginseng. This study aimed to prepare a valuable ginsenoside Compound K using ginseng extracts with the enzyme(Plantase). Plantase showed very efficient activity to produce Compound K from ginseng extracts. Plantase exhibited the highest activity at pH 5 and 50 ℃, as a result of investigating the yield of Compound K by changing the temperature and pH, while fixing the enzyme concentration to 10% or 15% over 48 hours of reaction time. Under optimium conditions, Plantase produced and accumulated Compound K over 35 wt% of whole ginseng extracts. Antimicrobial activitiy of bioconvertied ginseng extracts showed selectivity against Cutibacterium acnes KCTC 3314. Minimal inhibitory concentration (MIC) of bioconverted ginseng extract (35% of Compound K enriched extract) against Cutibacterium acnes KCTC 3314 strain is 31.25ug/mL. These results suggest that the Compound K enriched extract is potential materials for cosmetic products and Plantase is a very useful enzyme for Compound K production.

Standardization and HPTLC Fingerprinting of a Polyherbal Unani Formulation

  • Beg, Mirza Belal;Viquar, Uzma;Naikodi, Mohammad Abdul Rasheed;Suhail, Habiba;Kazmi, Munawwar Husain
    • CELLMED
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    • v.11 no.1
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    • pp.4.1-4.8
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    • 2021
  • Background: The Unani system of medicine has been practised since centuries for the treatment of a range of diseases. In spite of their efficacy they have been widely criticised due to the lack of standardization and poor quality control. Standardization of Unani medicine is a valuable issue at the present because they are very prone to contamination, deterioration, adulteration and variation in composition due to biodiversity as well as careless collection. Objective: To Standardize and Development of HPTLC Fingerprinting of a polyherbal Unani formulation Qurs-e-Safa. Materials and methods: The conventional and modern analytical techniques were used to standardise Qurs-e-Safa. The study was carried into three different batches of Qurs-e-Safa prepared with its ingredients. The parameters studied are organoleptic, microscopic, physicochemical parameters, phytochemical screening, TLC, HPTLC profile, aflatoxin, microbial load and heavy metal analysis. Results and conclusion: Qurṣ-e-Sa'fa is dark yellow in colour and aromatic smell. Uniformity of diameter and weight variation were found to be 13 ± 0, and 524.7 ± 1.72 mg. friability, hardness and disintegration time of all 3 batches were found to be (0.0615 ± 0.004, 0.0885 ± 0.0047 and 0.0725 ± 0.0058), (3.5 ± 0.2886, 3.67 ± 0.1674 and 3.67 ± 0.1674) and (16 to 17 minutes). Extractive value were found to be maximum in distilled water (38.488 ± 0.20, 37.3824 ± 0.38 and 39.8177 ± 0.13) followed by alcohol (27.5406 ± 0.54, 27.5656 ± 0.32 and 26.9229 ± 0.25). Loss of weight on drying, pH, total ash, acid insoluble ash, qualitative test was set in. Phytochemical screening revealed the presence of Carbohydrates, Phenols, Resins, Proteins, Steroids, fixed oil and Flavonoids. The microbial load was found absent and heavy metals were within permissible limits. The data evolved from the study may serve as a reference to validate and also help in the quality control of other finished products in future research.

Korean Musical Actress Jung Sun-Ah's Acting Skill and Style from the Projection and Back-projection Perspectives ('투사-역투사 이론' 관점의 한국 뮤지컬 배우 정선아의 연기 스킬과 스타일 특성)

  • Kim, Jeong-Seob;Lee, Eun-Hye
    • Journal of Korea Entertainment Industry Association
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    • v.15 no.4
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    • pp.45-54
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    • 2021
  • Jeong Sun-Ah built up her performance career for twenty years with bold and energetic acting and solidified her status as a leading actress of Korean musical since her debut. To benefit from the value of her experience this study performed an in-depth interview with her, applying the Theory of "Projection" and "Back-projection", which are the psychological principles of acting, and derived "acting(entering the roles)" and "de-acting(leaving the roles)" techniques. As result, Her acting mechanism involved emptying her ego, embodying a persona by projecting the role created by intensive exploration of materials like previous performance, film of the same title, original novel, and script, and then getting the ego back by back-projecting through dynamic activities such as overseas travel and dance. She pre-studied the roles by physically visiting sites that are important to the characters. She was unique in that she pursued a difference by changing vocal trainers for each musical production and undertook more intense physical training than vocal practice to achieve powerful singing performance. In most of her works (75%), she suffered from aftereffects such as depression, narcissism, hysteria, and insomnia due to disorder caused by breaking away from the roles. However, she relied on self-help and alternatives are needed in the future such as reinforcement of expert counselling. Jeong Sun-Ah appeared on an average of 1.6 productions per year, practiced for an average of 1.7 months, and performed for an average of 3.9 months with an average of 100 days of break between productions. Her performance record from this research demonstrates her constant preparation and passion, as well as the know-how of reserving and distributing energy. So, it has a valuable implications for acting education and self-management of actors and actress.

The Characteristics and Tasks of Park Yong-gil's Letter 'To You' Collection (박용길의 편지 '당신께' 컬렉션의 특성과 과제)

  • Oh, Myung Jin
    • The Korean Journal of Archival Studies
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    • no.72
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    • pp.205-239
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    • 2022
  • Park Yong-gil's personal letter 'To You' collection is a valuable historical document that contains aspects of modern and contemporary Korea, managed by the Late Spring Moon Ik-Hwan Memorial Foundation. These letters were written for about 10 years and 3 months, and there are currently about 2,304 letters left, and support is needed to secure social feasibility for long-term preservation of historical materials and to establish a stable record management system. The purpose of this article is to introduce Park Yong-gil's letter, which has not been introduced in earnest, to the archival community, and to comprehensively review the whole story and examine the tasks. To this end, the meaning of the letter in Park Yong-gil's personal life was examined, and the value of this letter was particularly highlighted in terms of being a letter written as a part of Okbaraji. And by investigating and analyzing the status of the archives, the internal and external characteristics of the letter were comprehensively analyzed. The characteristics of Park Yong-gil's letter identified as a result of the study are that it is a letter sent to one person, and it is accumulated with a considerable amount and aggregation. In particular, it is expected to have a diverse user base in that it is easy to empathize with because it contains the familiar subject matter of letters and the stories of contemporaries, and contains a variety of informational values about contemporary events and people. Based on these historical and cultural values and various useful values of the letter 'To you', various research and development of services should be made in the future.

Synthesis of Sludge Waste-derived Semiconductor Grade Uniform Colloidal Silica Nanoparticles and Their CMP Application (슬러지 폐기물을 활용한 반도체급 균일한 콜로이달 실리카 나노입자의 제조 및 CMP 응용)

  • Kim, Dong Hyun;Kim, Jiwon;Jekal, Suk;Kim, Min Jeong;Kim, Ha-Yeong;Kim, Min Sang;Kim, Sang-Chun;Park, Seon-Young;Yoon, Chang-Min
    • Journal of the Korea Organic Resources Recycling Association
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    • v.30 no.3
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    • pp.5-12
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    • 2022
  • This study suggests the effective recycling method of sludge waste from various industrial fields to synthesize uniform colloidal silica nanoparticles. In detail, polymers are removed from the sludge waste to attain sludge-extracted silica (s-SiO2) micron-sized particles, and ammonia assisted sonication is applied to s-SiO2, which has effectively extracted the silanol precursor. The nano-sized silica (n-SiO2) particles are successfully synthesized by a typical sol-gel method using silanol precursor. Also, the yield amounts of n-SiO2 are determined by the function of s-SiO2 etching time. Finally, n-SiO2-based slurry is synthesized for the practical CMP application. As a result, rough-surfaced semiconductor chip is successfully polished by the n-SiO2-based slurry to exhibit the mirror-like clean surface. In this regard, sludge wastes are successfully prepared as valuable semicondutor grade materials.

Comparative Evaluation of the Survival Rates of Zirconia Crown and Stainless Steel Crown for Proximal Caries in Primary Molars: a Retrospective Study (유구치 인접면 우식증 수복 시 지르코니아 전장관과 기성금속관의 생존율 비교 평가: 후향적 연구)

  • Gahui Jeong;Nanyoung Lee;Hyewon Shin;Suhyun Park;Myeongkwan Jih
    • Journal of the korean academy of Pediatric Dentistry
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    • v.50 no.3
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    • pp.307-317
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    • 2023
  • Due to increasing demand for aesthetics, zirconia crowns have become a popular choice for treating primary molars. However, there is limited literature available comparing the survival rates of zirconia crowns with those of other restorative materials. The objective of this study was to compare the 36-month survival rates of zirconia crowns and stainless steel crowns for proximal caries, as well as to analyze failure types associated with each crown type. Electronic medical records and radiographs of 1,061 primary molars from 498 patients treated with 2 types of prefabricated crowns at Chosun University Dental Hospital and 2 private dental clinics between 2017 and 2019 were collected and analyzed. The survival rate of zirconia crowns was found to be lower compared to that of stainless steel crowns. Regarding the groups without pulp treatment, the survival rate of stainless steel crowns was significantly higher than that of zirconia crowns. However, in the groups that received pulp therapy, no significant difference in the survival rates was observed between the two preformed crowns. Notably, abnormal root resorption or periapical lesions were identified as the primary cause of restorative failure in stainless steel crowns, whereas loss of restoration was the predominant cause in zirconia crowns. This study holds valuable implications for clinicians when selecting preformed crowns for primary molars.

Analysis of Eco-Citizenship Contents Elements in Home Economics Textbooks for the Introduction of Ecological Transformation Education (생태전환교육 도입을 위한 가정과 교과서의 생태시민성 내용 요소 분석)

  • Cho, Sung Mi;Park, Mi Jeong
    • Journal of Korean Home Economics Education Association
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    • v.35 no.2
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    • pp.1-20
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    • 2023
  • The purpose of this study is to extract and analyze ecological citizenship elements in the middle school home economics textbook used in the 2015 national curriculum for the introduction of ecological transformation education in the 2022 national curriculum. As a result of the analysis, the content analysis of the ecological citizenship factor was validated by six experts who are incumbent middle school home economics teachers, and the S-CVI value was 0.97, ensuring the validity of the ecological citizenship factor analysis. The results of analyzing 242 ecological citizenship factors extracted from home economics textbooks are as follows. According to the content area of the 2015 national home economics curriculum, the 'human development and family' area had the highest presence of ecological citizenship factors followed by the 'resource management and self-reliance' area and the 'home life and safety' area. Among the categories of ecological citizenship factors, 'value⋅attitude' was the most frequent, followed by 'process⋅function' and 'knowledge⋅understanding'. For each textbook composition system, ecological citizenship elements were extracted in the order of pictures, text, activities, and supplementary materials. There was a significant variation in the number of ecological citizenship factors among publishers, indicating the importance of the textbook writers' perception, interpretation, and direction of writing. Based on these analysis results, ecological citizenship teaching and learning activities applicable to home economics education were presented. This study highlights the potential for practicing ecological citizenship education in line with the new orientation of the curriculum on ecological transformation education through home economics education. Furthermore, it provides valuable baseline data for the development and implementation of textbooks for the 2022 national curriculum.

Improvement of Pre-harvest Sprouting Resistance in Korean japonica Varieties through a Precision Marker-based Breeding

  • Kamal Bhattarai;Patricia Izabelle Lopez;Sherry Lou Hechanova;Ji-Ung Jeung;Hyun-Sook Lee;Eok-Keun Ahn;Ung-Jo Hyun;Jong-Hee Lee;So-Myeong Lee;Jose E. Hernandez;Sung-Ryul Kim
    • Proceedings of the Korean Society of Crop Science Conference
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    • 2022.10a
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    • pp.269-269
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    • 2022
  • Pre-harvest sprouting (PHS) on rice panicles is getting problematic in recent several years in Korea due to climate changes such as high temperature and more frequent typhoons during harvesting season. PHS negatively affects grain quality severely and also yield. Genetic improvement of Korean varieties (Oryza sativa ssp. japonica) through a marker assisted-backcross breeding (MAB) with the known PHS resistant genes must be one of ideal solutions. However, the final breeding products of MAB occasionally exhibit unwanted traits, especially the cross between genetically distant parents. This might be caused by linkage drag and/or presence of the gene-unlinked donor introgressions, resulting that the final products could not be released to the farmers. The major PHS resistance gene, Sdr4 (Seed dormancy 4) originated from an indica cultivar, Kasalath was selected as a donor gene. In order to avoid unexpected phenotypes in the breeding products, we performed a precision marker-based breeding (PMBB) consisting of foreground, recombinant, and background selections (FS, RS, and BS) which aim to develop 'single small introgression lines' (~100 kb introgression). Korean varieties (Ilpum and Gopum) were crossed with Kasalath. We developed Sdr4-allele specific markers for FS and a set of polymorphic flanking markers near the Sdr4 (-350kb and +420kb) for RS. To minimize linkage drag, the small introgression (< 125kb) containing Sdr4 was selected in Ilpum background (BC2F4) through 1st RS with ~1,200 F2 or BC1F2 plants (one side trimmed) and then 2nd RS with ~1,000 progenies from the 1st RS selected plants (another side trimmed). After RS, the selected lines were genotyped by using Infinium 7K SNP chip to detect other donor introgressions and the lines were backcrossed. Currently BS is on-going from the backcross-derived progenies with BS markers to remove residual introgressions. During the PMBB process, genetic effect of Sdr-4-Kasalath allele was confirmed in Ilpum and Gopum backgrounds by PHS phenotyping using the segregating BC2F3 or BC1F4 materials. The Sdr4 PMBB lines in Ilpum background (< 125kb introgression) will be valuable genetic resources to improve PHS resistance in modem popular temperate japonica varieties.

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A Study of the 'Sinchungmyeong Jochong(辛丑銘鳥銃)' at the National Museum of Korea - Attribute analysis and point of use estimation - (국립중앙박물관 소장 '신축명 조총(辛丑銘鳥銃)'연구 - 속성 분석과 운용 시기 추정을 중심으로 -)

  • KIM Myunghoon
    • Korean Journal of Heritage: History & Science
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    • v.56 no.4
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    • pp.6-22
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    • 2023
  • The National Museum of Korea's 'Shinchungmyeong Jochong' is the sole firearm in the country bearing inscriptions written in ink('辛丑改備江華庫藏'). Thanks to this written record, it is possible to determine where this firearm was stored and to make an estimate of the time when it was stored. Additionally, it is a valuable artifact that has been exceptionally well preserved and has an artistic design. However, research into the operational period, form, and structural characteristics of this firearm has been limited to date. This study aimed to shed light on the operational period, form, and structural features of the 'Shinchukmyeong Jochong.' To achieve this, the specifications and structural characteristics of the firearm were examined, and comparisons were made with 17 other extant firearms and their attributes. The results confirmed that the 'Shinchungmyeong Jochong' is a representative example of the typical firearms of the Joseon Dynasty. Next, the timing, background, and production subject of the Ganghwado containment of the Jochong were tracked based on letters found with the Jochong. The investigation revealed an entry in the 'Records of King Jeongjo'(『正祖實錄』) indicating that a significant amount of military supplies, including firearms, were stored on Ganghwado in December of the 5th year of Shinchung(1781). The decision to store these materials in Ganghwado Island may have been due to the perception of the Joseon decision-makers, who strategically valued Ganghwado Island, and the relocation of 'Tongaoyeong'(統禦營) and the integration with 'Jinmuyeong'(鎭撫營). After acquisition, it is presumed that the firearm was operated at locations like 'Jinmuyeong'(鎭撫營). The firearm's production is presumed to have been associated associated with institutions such as 'Gungisi'(軍器寺). In conclusion, the 'Shinchungmyeong Jochong' exemplifies a typical firearm of the Joseon Dynasty, and it is likely that it was stored on Ganghwado in December of 1781. Its production is believed to have been related to institutions such as 'Gungisi'. Following its acquisition, it is presumed that the firearm was operated at locations including 'Jinmuyeong'.