• Title/Summary/Keyword: 현장보존

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Assessment and Calibration of Ultrasonic Velocity Measurement for Estimating the Weathering Index of Stone Cultural Heritage (석조문화재의 풍화지수 산정을 위한 초음파속도의 평가 및 보정)

  • Lee, Young-Jun;Keehm, Young-Seuk;Lee, Min-Hui;Han, June-Hee;Kim, Min-Su
    • Journal of the Korean earth science society
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    • v.33 no.2
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    • pp.126-138
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    • 2012
  • Ultrasonic method is widely used for the evaluation of weathering index and of degree of deterioration because it is easily applicable $in$ $situ$. The basic idea of the method is that the ultrasonic velocity decreases as a rock is being weathered. Thus, the difference of ultrasonic velocities between fresh rock and weathered rock indicates the degree of weathering. In this method, the ultrasonic velocity of fresh rock is assumed to be 5,000 m/s. However, this assumption can cause significant errors in estimating weathering index, especially in case that those rocks of the same type have a wide range of ultrasonic velocities such as in Korea. Therefore, we obtained twenty rock specimens and sixty core samples commonly used for stone cultural heritages in Korea, and measured ultrasonic velocities. From the results, we found that the ultrasonic velocities of the same rock type, granite samples range from 3,118 to 5,380 m/s, and that the estimated weathering index can be highly biased if we use the fixed value of 5,000 m/s. We created a database (DB) by combining the measurement data and reported it. We also measured ultrasonic velocities by direct and indirect methods to quantify the calibration coefficient for each sampling site. We found that the calibration coefficients vary widely from site to site (1.31-1.76). Other factors, such as operator bias and temperature did not show any significant effect on errors in ultrasonic velocity measurements. Lastly, we applied our ultrasonic velocity DB and calibration coefficients to a stone cultural heritage, Bonghwang-ri Buddha statue. Our estimation of the weathering index was 0.3, 0.1 smaller than that by conventional method. The degree of deterioration was also different, "moderately weathered", while conventional method gave "highly weathered". Since other independent studies reported that the degree of deterioration of the Buddha statue was "moderately weathered", our estimation seems to be more accurate. Thus our method can help accurately evaluate the weathering index and the conservation planning for a stone cultural heritage.

A COMPARATIVE STUDY OF PRESERVING ABILITY OF HUMAN PERIODONTAL LIGAMENT CELLS STORED IN DIFFERENT STORAGE MEDIA (수종의 저장용액에서 치주인대세포의 생존율 비교)

  • Choi, Won-Kyung;Choi, Hyung-Jun;Choi, Byung-Jai;Lee, Jong-Gap
    • Journal of the korean academy of Pediatric Dentistry
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    • v.26 no.2
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    • pp.427-436
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    • 1999
  • Preservation of the remaining periodontal ligament cells on an avulsed tooth is very important to the successful outcome of replantation. HBSS is recommended as the most suitable storage medium for the avulsed tooth that cannot be replanted immediately. But their availability near the site of an accident is doubtful. The purpose of this in vitro study was to compare periodontal ligament cells stored in different storage media obtained easily on the spot. Human periodontal ligament cells were collected from the premolar teeth extracted for orthodontic treatment. Cells were cultured in ${\alpha}-MEM$ culture medium containing 20% FBS, at $37^{\circ}C$ 100% humidity, in a 5% $CO_2$ incubator. Cells were cultured in 96 well culture plate, $5{\times}10^4$ cells per well with ${\alpha}-MEM$ and incubated for 24 hours. After discarding the medium, those cells were cultured in ${\alpha}-MEM$ contained with 10% FBS, pasteurized milk, sterilized saline, unstimulated saliva and bench-dried state at $25^{\circ}C$ room temperature for 30, 60, 90, 120, 180 minutes respectively. And then each group was measured using MTT assay. The results were as follows. 1. Between the group of each time, there was statistically significant difference. Periodontal ligament cells viability was highest in pasteurized milk and was reduced stepwisely in sterilized saline, unstimulated saliva and bench-dried state(p<0.05). 2. between the time of each group, there was statistically significant difference(p<0.05) but was no statistically significant difference at 90-120 minutes in pasteurized milk and at 60-90 minutes and 120-180 minutes in sterilized saline(p>0.05). In conclusion, HBSS as storage medium of an avulsed tooth is not practical on the spot. Insteadily pasteurized milk can be recommended to maintain the periodontal ligament cells viability.

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Quality Characteristics of Korean Chive (Allium tuberosum Rotter) as affected by Inner Film Packaging Methods in Paper Box (부추의 종이박스 내 속포장에 따른 품질 특성)

  • Jang, Min Sun;Lee, Jung-Soo;Chandra, Dulal;Choi, Jee Won;Lee, Jin-Su;Park, Me Hea;Choi, Hyun Jinn;Hong, Yuun Pyo;Kim, Ji Gang
    • KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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    • v.23 no.3
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    • pp.143-150
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    • 2017
  • Effects of packaging methods for maintaining the shelf-life and postharvest quality of Korean chive (Allium tuberosum Rotter) usually called buchu in Korea was studied during fall season. Buchu, which has high moisture content and active metabolism after harvest, is characterized by the greater changes in quality during storage and distribution. It is usually packaged in paper box during distribution in domestic channel in Korea where the marketability ends within few days of harvest. In order to maintain the commercial quality of buchu, we tried to use inner film with or without absorbent paper in commercial paper box packaging. The 'Greenbelt' cultivar of buchu was harvested in october and packaged in corrugated paper box (A), in corrugated paper box with micro-perforated high density polyethylene (HDPE) film as inner material (B), a layer of absorbent paper both at the bottom and top of buchu in corrugated paper box (C) and a combination of HDPE film as inner material along with a layer of absorbent paper both at the bottom and top of buchu in corrugated paper box (D), and stored at $5^{\circ}C$ for up to 21 days. Several quality parameters such as fresh weight loss, respiration rate, color, chlorophyll content and sensory qualities were monitored during storage. When buchu was packaged only in paper box, the appearance and quality deteriorated rapidly through decay development thereby sample became unmarketable within 12 days. On the other hand, buchu packaged with inner HDPE film maintained its quality, good visual appearance and exhibited a longer period of marketable life compared to the samples stored in other treatments. However, the use of absorbent paper did not have any significant effect in maintaining quality of buchu. The uses of inner HDPE film was effective in reducing weight loss that resulted better visual appearance of buchu. Results suggest that the use of inner HDPE film in bulk type corrugated paper box packaging and storing at $5^{\circ}C$ could be the optimum condition for commercial storage of buchu. Further investigation on other quality parameters and packaging methods would be useful in maintaining the quality aspects of buchu at postharvest stages.

A Study On the Geographic Locations of Dongcheons(洞天) in Gyeongsang-Do (경상도지역 동천(洞天)의 위치 조사 연구)

  • Kang, Kee-Rae;Lee, Hae-Ju;Bae, Jun-Gyu;Kim, Hee-Chae;Kim, Chang-Jun;Lee, Hyun-Chae;Kim, Dong-Phil;Kim, Cha-Kwon
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.36 no.3
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    • pp.16-25
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    • 2018
  • Initially from the Taoist scriptures, 'Dongcheon' is a term that can be regarded as a symbolic place in the real world for the enlightened ones who received relief and peace by restoring the human nature taught in the Confucian school. The long for an ideal world apart from the reality embodied as the labeling some places 'Dongcheon,' and the term was used to refer to a scenery where the ideal fairyland is reproduced. Besides, 'Dongcheon' was a term often used by Confucian scholars for various purposes including the attachment to the nearby landscapes, expressing homogeneity and superiority through placeness and the beautification of settlement spaces. This paper is the result of a field study on 'Dongcheon' in the Gyeongsang-Do. The research was conducted from March to August 2018, and we carried out firsthand location surveys on Dongcheons, of which some were lost, others were fairly preserved, and still others could not be located as only their existences were passed down orally. According to the field survey, there were total 111 inscriptions or engravings on the plates in Gyeongsang-Do that include the term 'Dongcheon.' There were 79 'Dongcheon' inscriptions confirmed in the Gyeongsangbuk-Do region: twenty in Yeongju-City, sixteen in Bonghwa-Gun, eleven in Andong-City and seven in Yeongyang-Gun and Ulgin-Gun. Among them, two were in the form of a wooden sign, and six were erected as rock signposts. Fourteen stops reported in the literature were lost or unidentified. Also, among the sixteen signs in Bonghwa-Gun, nine were cursive engravings. Meanwhile, there were 26 Dongcheon inscriptions in the Gyeongsangnam-Do region. Hamyang-Gun and Sancheong-Gun anf Hadong-Gun each housed three inscriptions, and seven places were in the form of rock signposts. 'Hwagaedongcheon' and 'Geumsandongcheon' could not be identified in inscriptions although they appear in Jibong Yuseol and Taengniji with stories of Choi Chiwon. The significance of this study is as a reference for future researches in traditional scenery, epigraphs, or as primary data that helps cultural exploration in the region.

The State Hermitage Museum·Northwest University for Nationalities·Shanghai Chinese Classics Publishing House Kuche Art Relics Collected in Russia Shanghai Chinese Classics Publishing House, 2018 (아라사국립애이미탑십박물관(俄羅斯國立艾爾米塔什博物館)·서북민족대학(西北民族大學)·상해고적출판사(上海古籍出版社) 편(編) 『아장구자예술품(俄藏龜玆藝術品)』, 상해고적출판사(上海古籍出版社), 2018 (『러시아 소장 쿠차 예술품』))

  • Min, Byung-Hoon
    • MISULJARYO - National Museum of Korea Art Journal
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    • v.98
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    • pp.226-241
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    • 2020
  • Located on the right side of the third floor of the State Hermitage Museum in St. Petersburg, the "Art of Central Asia" exhibition boasts the world's finest collection of artworks and artifacts from the Silk Road. Every item in the collection has been classified by region, and many of them were collected in the early twentieth century through archaeological surveys led by Russia's Pyotr Kozlov, Mikhail Berezovsky, and Sergey Oldenburg. Some of these artifacts have been presented around the world through special exhibitions held in Germany, France, the United Kingdom, the Netherlands, Korea, Japan, and elsewhere. The fruits of Russia's Silk Road expeditions were also on full display in the 2008 exhibition The Caves of One Thousand Buddhas - Russian Expeditions on the Silk Route on the Occasion of 190 Years of the Asiatic Museum, held at the Hermitage Museum. Published in 2018 by the Shanghai Chinese Classics Publishing House in collaboration with the Hermitage Museum, Kuche Art Relics Collected in Russia introduces the Hermitage's collection of artifacts from the Kuche (or Kucha) region. While the book focuses exclusively on artifacts excavated from the Kuche area, it also includes valuable on-site photos and sketches from the Russian expeditions, thus helping to enhance readers' overall understanding of the characteristics of Kuche art within the Buddhist art of Central Asia. The book was compiled by Dr. Kira Samosyuk, senior curator of the Oriental Department of the Hermitage Museum, who also wrote the main article and the artifact descriptions. Dr. Samosyuk is an internationally renowned scholar of Central Asian Buddhist art, with a particular expertise in the art of Khara-Khoto and Xi-yu. In her article "The Art of the Kuche Buddhist Temples," Dr. Samosyuk provides an overview of Russia's Silk Road expeditions, before introducing the historical development of Kuche in the Buddhist era and the aspects of Buddhism transmitted to Kuche. She describes the murals and clay sculptures in the Buddhist grottoes, giving important details on their themes and issues with estimating their dates, and also explains how the temples operated as places of worship. In conclusion, Dr. Samosyuk argues that the Kuche region, while continuously engaging with various peoples in China and the nomadic world, developed its own independent Buddhist culture incorporating elements of Gandara, Hellenistic, Persian, and Chinese art and culture. Finally, she states that the culture of the Kuche region had a profound influence not only on the Tarim Basin, but also on the Buddhist grottoes of Dunhuang and the central region of China. A considerable portion of Dr. Samosyuk's article addresses efforts to estimate the date of the grottoes in the Kuche region. After citing various scholars' views on the dates of the murals, she argues that the Kizil grottoes likely began prior to the fifth century, which is at least 100 years earlier than most current estimates. This conclusion is reached by comparing the iconography of the armor depicted in the murals with related materials excavated from the surrounding area (such as items of Sogdian art). However, efforts to date the Buddhist grottoes of Kuche must take many factors into consideration, such as the geological characteristics of the caves, the themes and styles of the Buddhist paintings, the types of pigments used, and the clothing, hairstyles, and ornamentation of the depicted figures. Moreover, such interdisciplinary data must be studied within the context of Kuche's relations with nearby cultures. Scientific methods such as radiocarbon dating could also be applied for supplementary materials. The preface of Kuche Art Relics Collected in Russia reveals that the catalog is the first volume covering the Hermitage Museum's collection of Kuche art, and that the next volume in the series will cover a large collection of mural fragments that were taken from Berlin during World War II. For many years, the whereabouts of these mural fragments were unknown to both the public and academia, but after restoration, the fragments were recently re-introduced to the public as part of the museum's permanent exhibition. We look forward to the next publication that focuses on these mural fragments, and also to future catalogs introducing the artifacts of Turpan and Khotan. Currently, fragments of the murals from the Kuche grottoes are scattered among various countries, including Russia, Germany, and Korea. With the publication of this catalog, it seems like an opportune time to publish a comprehensive catalog on the murals of the Kuche region, which represent a compelling mixture of East-West culture that reflects the overall characteristics of the region. A catalog that includes both the remaining murals of the Kizil grottoes and the fragments from different parts of the world could greatly enhance our understanding of the murals' original state. Such a book would hopefully include a more detailed and interdisciplinary discussion of the artifacts and murals, including scientific analyses of the pigments and other materials from the perspective of conservation science. With the ongoing rapid development in western China, the grotto murals are facing a serious crisis related to climate change and overcrowding in the oasis city of Xinjiang. To overcome this challenge, the cultural communities of China and other countries that possess advanced technology for conservation and restoration must begin working together to protect and restore the murals of the Silk Road grottoes. Moreover, centers for conservation science should be established to foster human resources and collect information. Compiling the data of Russian expeditions related to the grottoes of Kuche (among the results of Western archaeological surveys of the Silk Road in the early twentieth century), Kuche Art Relics Collected in Russia represents an important contribution to research on Kuche's Buddhist art and the Silk Road, which will only be enhanced by a future volume introducing the mural fragments from Germany. As the new authoritative source for academic research on the artworks and artifacts of the Kuche region, the book also lays the groundwork for new directions for future studies on the Silk Road. Finally, the book is also quite significant for employing a new editing system that improves its academic clarity and convenience. In conclusion, Dr. Kira Samosyuk, who planned the publication, deserves tremendous praise for taking the research of Silk Road art to new heights.

IPA Study of Landscape Potentiality of Agricultural and Fishery Heritages - A Focus on Cheongsando - (농어업유산의 경관 잠재력 파악을 위한 IPA 연구 - 청산도를 중심으로 -)

  • Kim, Dong-Chan;Choi, Woo-Young
    • Journal of the Korean Institute of Landscape Architecture
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    • v.42 no.4
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    • pp.76-88
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    • 2014
  • The purpose of this study is to derive landscape characteristic elements of agricultural and fishery heritage and to classify landscape characteristic elements of Cheongsando designated as Korean agricultural and fishery heritage No.1 as well as a Globally Important Agricultural Heritage System (GIAHS). Additionally, this study was conducted to suggest priority for conservation and management of Cheongsando by grasping differences between factors which visitors deem as important and satisfying. To implement this study, the literature review was written, an on-site survey to derive landscape characteristic elements of Cheongsando and a survey on importance and satisfaction of landscape characteristic elements of Cheongsando were conducted, and reliability analysis, descriptive statistical analysis and IPA analysis were performed using SPSS 20.0. The results are as follows: The analysis showed the factors requiring persistent efforts in the first quadrant are the rape flower garden, the sea, green barley field, flat stone paddy field, breakwater and lighthouse, abalone farms, stone houses, thatched houses, a coastal road, the slow road, Stonewall Walkway of Seongseo Village, and residents' agricultural behaviors. The analysis showed the factors needing intensive management strategies in the second quadrant are the surrounding mountain area, dock, Docheong Harbor, vessels, fish market, Doksari stone wall, garish-roofed farm villages, excursion school to a slow island, pension and cafe, bus stop, shade trees, Raw Fish Street, the beach and the filming site. Analysis indicated that the factors needing management control in the third quadrant are the pine grove, the beach, tidal mudflat, the garlic fields, vinyl greenhouses, grain drying yard, sea mustard drying yard, heritage center, Choboon, Dangri exorcism, the market place, residents' fishery behaviors, residents' industrial behaviors, residents' ordinary behaviors, visitors' behaviors that visiting the dock, visitors' behaviors that walking the slow road, visitors' behaviors that eating and shopping for specialties, visitors' behaviors that experiencing agriculture and fishery. Excessive effort factors in the fourth quadrant were not derived.

Studies on the Investigation into Original Form of Natural Monument No.404 Orijangnim in Jacheon-ri, Yeongcheon (천연기념물 제404호 영천 자천리 오리장림의 원형 규명)

  • Lim, Won-Hyeon
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.31 no.3
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    • pp.83-94
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    • 2013
  • The purpose of this study is to offer basic data about prototype conservation of the Orijangnim, natural monument No. 404. For this study, March to August 2010, was a literature surveys and field research, and based on this, the Delphi survey of local residents and experts meeting were diagnosed with forest back ground, spatial extent, in the form of forests, flora and vegetation of the surrounding area, so examined closely the original form. Range of the Orijangnim was presumed from Jacheon middle school entrance($N36^{\circ}05^{\prime}59.9^{{\prime}{\prime}}/E128^{\circ}54^{\prime}32.9^{{\prime}{\prime}}$) to Odong of Hwabukmyeon village entrance($N36^{\circ}05^{\prime}31.0^{{\prime}{\prime}}/E128^{\circ}54^{\prime}32.5^{{\prime}{\prime}}$). The Orijangnim in the original form of the existing forest surrounding the village along gohyeon river going back a long S-shaped about 2km is considered. The investigated vascular plants consist of total 198 taxa : 2 forms, 20 varieties, 179 species, 152 Genera, 72 Families. Most of the 60 kinds of large land plants lots of whole plants accounted for 33.3%. A main vegetation of the Orijangnim have been distributed 473 objects of 21 species, and evergreen conifers is 19% to 92 objects, on the other hand, deciduous broadleaf tree is 79% to 373 objects, so the Orijangnim can be maxed forest that deciduous broadleaf tree is dominant. When consider the composition purpose of forest, environment of location, tree size, surrounding flora and vegetation, because an original vegetation of Orijangnim is suggested Zelkova serrata, Salix glandulosa, Celtis sinensis Pers., Quercus variabilis, Quercus acutissima , Sophora japonica L., Cornus walteri Wanger. we must restore around such species of tree. Cedrus deodara (Roxb.) Loudon, Chaenomeles sinensis, Prunus yedoensis Matsum., Ginkgo biloba , Pinus thunbergii Parl., Populus tomentiglandulosa T. Lee is considered to have been planted in the last.

Identifying Landscape Perceptions of Visitors' to the Taean Coast National Park Using Social Media Data - Focused on Kkotji Beach, Sinduri Coastal Sand Dune, and Manlipo Beach - (소셜미디어 데이터를 활용한 태안해안국립공원 방문객의 경관인식 파악 - 꽃지해수욕장·신두리해안사구·만리포해수욕장을 대상으로 -)

  • Lee, Sung-Hee;Son, Yong-Hoon
    • Journal of the Korean Institute of Landscape Architecture
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    • v.46 no.5
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    • pp.10-21
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    • 2018
  • This study used text mining methodology to focus on the perceptions of the landscape embedded in text that users spontaneously uploaded to the "Taean Travel"blogpost. The study area is the Taean Coast National Park. Most of the places that are searched by 'Taean Travel' on the blog were located in the Taean Coast National Park. We conducted a network analysis on the top three places and extracted keywords related to the landscape. Finally, using a centrality and cohesion analysis, we derived landscape perceptions and the major characteristics of those landscapes. As a result of the study, it was possible to identify the main tourist places in Taean, the individual landscape experience, and the landscape perception in specific places. There were three different types of landscape characteristics: atmosphere-related keywords, which appeared in Kkotji Beach, symbolic image-related keywords appeared in Sinduri Coastal Sand Dune, and landscape objects-related appeared in Manlipo Beach. It can be inferred that the characteristics of these three places are perceived differently. Kkotji Beach is recognized as a place to appreciate a view the sunset and is a base for the Taean Coast National Park's trekking course. Sinduri Coastal Sand Dune is recognized as a place with unusual scenery, and is an ecologically valuable space. Finally, Manlipo Beach is adjacent to the Chunlipo Arboretum, which is often visited by tourists, and the beach itself is recognized as a place with an impressive appearance. Social media data is very useful because it can enable analysis of various types of contents that are not from an expert's point of view. In this study, we used social media data to analyze various aspects of how people perceive and enjoy landscapes by integrating various content, such as landscape objects, images, and activities. However, because social media data may be amplified or distorted by users' memories and perceptions, field surveys are needed to verify the results of this study.

Geochemical Characteristics and Heavy Metal Pollutions in the Surface Sediments of Oyster Farms in Goseong Bay, Korea (고성만 굴 양식장 표층퇴적물의 지화학적특성과 중금속 오염에 관한 연구)

  • Kang, Ju-Hyun;Lee, Sang-Jun;Jeong, Woo-Geon;Cho, Sang-Man
    • The Korean Journal of Malacology
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    • v.28 no.3
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    • pp.233-244
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    • 2012
  • Goseong bay, located in southeast sea of Korea with an area of 2,100 ha, is a semi-enclosed bay well-known for oyster farming cultured in an extended range of 148 ha. The objective of this study is to provide the fundamental data in order to manage the effective sea area. A total 26 of surface sediment were collected from Goseong bay to evaluate their sedimentary environment and heavy metals. The loss on Ignition (LOI), C/N ratio, acid volatile sulfide (AVS) and heavy metals were analyzed. loss on ignition (LOI) of surface sediment range from 1.00% to 3.03% (average 2.00%). The carbonate content ranges from 0.52% to 4.29% (average 2.37%). C/N ratio of organic matter showed that most part of organic matter comes from neighboring continent. Acid volatile sulfide (AVS) value of surface sediment from 0.02 mg/g to 1.43 mg/g (average 0.24 mg/g). A ten element of surface sediments (Al, As, Cd, Cr, Cu, Hg, Ni, Pb, V, Zn) were calculated by enrichment factor (Ef) and the results show that some areas are highly polluted with respect Cu and Hg. The correlation matrix displays the existence of remarkable levels of correlation with both positive and negative values among different variable pairs. LOI and AVS showed both positive values. LOI and AVS values falls under 2% and 1%. Therefore, Goseong bay showed good in quality of sediment.

Development of a Theme-Selection Activity in 'Clothing Life' in Relation to SDGs for the Free Semester Program (지속가능발전목표(SDGs) 성취를 위한 의생활 자유학기제 주제선택활동 프로그램 개발)

  • Choi, Ye Ji;Park, Mi-Jeong;Shim, Huen-Sup
    • Journal of Korean Home Economics Education Association
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    • v.32 no.3
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    • pp.27-48
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    • 2020
  • The purpose of this study is to develop a theme-selection activity in 'clothing life' in relation to SDGs(Sustainable Development Goals) for the free semester program. After analyzing the contents of the 'clothing life' area of middle school home economics textbooks based on the SDGs, the content system and learning goals were set. Then a program was developed and the validity and the feasibility of the program were verified. As a result of the analysis of textbooks, the contents of 'clothing life' included all the three basic dimensions of social development, economic growth, and environment protection, yet focus only on 1 or 2 goals of each area. Based on the results of the analysis, a 'Righteous(義) Clothing(衣) Life' program was developed. The developed program consists of teaching-learning process plans and teaching-learning materials in eight class periods, including 'The future everyone dreams of' based on SDG12, 'Two faces of fast fashion' based on SDG1, SDG5, SDG8, SDG10, 'Living as Homoclimatus' based on SDG13, and 'The future we create' based on SDG9 and SDG12. Through the expert evaluation process for the developed program, the program's teaching and learning adequacy and feasibility were reviewed and feedback was actively reflected to correct and supplement the program. Through this study, it is expected that it will contribute to laying the foundation for establishing home economics as a subject that educates citizens who practice sustainable life, and a pivotal subject in education for sustainable development.