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Corrosion Characteristics of Excavated Bronze Artifacts According to Corrosion Environment (부식 환경에 따른 출토 청동 유물의 부식 특성)

  • Jang, Junhyuk;Bae, Gowoon;Chung, Kwangyong
    • Korean Journal of Heritage: History & Science
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    • v.53 no.1
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    • pp.24-33
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    • 2020
  • In excavated bronze artifacts, corrosion products of various shapes and colors are observed due to multiple corrosion factors coexisting in the burial environment, and these corrosion products can constitute important data not only in terms of long-term corrosion-related information, but also in connection with preservation of artifacts. As such, scientific analysis is being carried out on the corrosion layer and corrosion products of bronze artifacts, and the corrosion mechanism and the characteristics of corrosion products elucidated, which is essential for interpreting the exposed burial environment and its association with corrosion factors inside the burial environment. In this study, after classifying excavated bronze artifacts according to alloy ratio and fabrication technique, comprehensive analysis of the surface of corrosion artifacts, corrosion layer, and corrosion products was carried out to investigate the corrosion mechanism, formation process of the corrosion layer, and characteristics of corrosion products. The study designated two groups according to alloy ratio and fabrication technique. In Group 1, which involved a Cu-Sn-Pb alloy and had no heat treatment, the surface was rough and external corrosion layers were formed on a part, or both sides, of the inside and the outside, and the surface was observed as being green or blue. α+δ phase selection corrosion was found in the metal and some were found to be concentrated in an empty space with a purity of 95 percent or more after α+δ phase corrosion. The Cu-Sn alloy and heat-treated Group 2 formed a smooth surface with no external corrosion layer, and a dark yellow surface was observed. In addition, no external corrosion layer was observed, unlike Group 1, and α corrosion was found inside the metal. In conclusion, it can be seen that the bronze artifacts excavated from the same site differ in various aspects, including the formation of the corrosion layer, the shape and color of the corrosion products, and the metal ion migration path, depending on the alloy ratio and fabrication technique. They also exhibited different corrosion characteristics in the same material, which means that different forms of corrosion can occur depending on the exposure environment in the burial setting. Therefore, even bronze artifacts excavated from the same site will have different corrosion characteristics depending on alloy ratio, fabrication technique, and exposure environment. The study shows one aspect of corrosion characteristics in specific areas and objects; further study of corrosion mechanisms in accordance with burial conditions will be required through analysis of the corrosive layer and corrosive product characteristics of bronze artifacts from various regions.

Flow Behavior and Mixing Characteristics of Rice Husk/Silica Sand/Rice Husk Ash (왕겨/모래/왕겨 회재의 유동 및 혼합 특성 연구)

  • Kim, Bo Hwa;Seo, Myung Won;Kook, Jin Woo;Choi, Hee Mang;Ra, Ho Won;Yoon, Sang Jun;Mun, Tae Young;Kim, Yong Ku;Lee, Jae Goo;Rhee, Young Woo
    • Korean Chemical Engineering Research
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    • v.54 no.4
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    • pp.533-542
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    • 2016
  • We investigate fluidization characteristics of the mixture of rice husk, silica sand and rice husk ash as a preliminary study for valuable utilization of rice husk ash obtained from gasification of rice husk in a fluidized bed reactor. As experiment valuables, the blending ratio of rice husk and sand (rice husk: sand) is selected as 5:95, 10:90, 20:80 and 30:70 on a volume base. Rice husk ash was added with 6 vol% of rice husk for each experiment and air velocity to the reactor was 0~0.63 m/s. In both rice husk/sand and rice husk/sand/ash mixture, the minimum fluidization velocity (Umf) is observed as 0.19~0.21 m/s at feeding of 0~10 vol.% of rice husk and 0.30 m/s at feeding of 20 vol.% of rice husk. With increasing the amount of rice husk up to 30 vol.%, $U_{mf}$ can not measure due to segregation behavior. The mixing index for each experiment is determined using mixing index equation proposed by Brereton and Grace. The mixing index of the mixture of rice husk/sand and rice husk/sand/ash was 0.8~1 and 0.88~1, respectively. The optimum fluidization condition was found for the good mixing and separation of rice husk ash.

Evaluation of Ecological Niche for Major Tree Species in the Natural Deciduous Forest of Mt. Chumbong (점봉산(點鳳山) 일대(一帶) 천연활엽수림(天然闊葉樹林)의 주요(主要) 구성(構成) 수종(樹種)에 대한 생태지위(生態地位) 평가(評價))

  • Kim, Guang Ze;Kim, Ji Hong
    • Journal of Korean Society of Forest Science
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    • v.90 no.3
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    • pp.380-387
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    • 2001
  • The characteristics of ecological niche, breadth and overlap, for seventeen major tree species were evaluated in the natural deciduous forest in Mt. Chumbong area. Employed by the plot sampling method, the environmental gradient for vertical niche was based on the intensity of light within the forest, and that for horizontal niche was based on multi-dimensional resources in distribution pattern. The result showed that Fraxinus rhynchophylla had the highest value of vertical niche breadth and Maackia amurensis had the lowest, and Acer pseudo-sieboldianum had the highest value of horizontal niche breadth and Betula costata had the lowest. There was no significant correlation between both measures of niche breadth. However, the tolerance index for each species was positively correlated to the values of niche breadth. Spearman's rank correlation coefficients were applied to test the correlationship between the species ranks of tolerance index and those of two ecological niche breadths. The coefficient of $r_s=0.432$ ($P{\leq}0.1$) was not enough to support significant correlationship between the tolerance index and vertical niche breadth at the 95% probability. If Carpinus cordata, rarely reach canopy of the forest due to its own growth form, are excluded from the analysis, coefficient was calculated as $r_s=0.650$ ($P{\leq}0.01$), resulting in highly significant correlationship. The Spearman's rank correlation coefficient was $r_s=0.797$ ($P{\leq}0.01$) for tolerance indices and the values of horizontal niche breadth, indicating highly significant. Four distinctive species groups, produced by cluster analysis on the basis of ecological niche overlap for each pair of species, were in considerable accord with the positively associated species constellation pattern created by the inter-species association analysis.

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A Study on Natural Scene Figuration Possibility - Centering around Gyeongnam Area(Namhae Gacheon Village, Sancheong Imchon Village, Hamyang Doma Village) Rice Terraces - (자연경관 조형화 가능성에 관한 연구 - 경남지역(남해가천마을, 산청임촌마을, 함양도마마을) 다랑이논을 중심으로 -)

  • Youn, Kyung-Sook;Lee, Jae-Keun
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.28 no.1
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    • pp.113-119
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    • 2010
  • This study examined figurative characters of rice terraces, and is intended to seek figurative possibility of a natural scene by selecting Gyeongnam Area Namhae Gacheon rice terraces, Sancheong Imcheon rice terraces and Hamyang Macheon rice terraces through an analysis of the target land. As a theoretical background, studies of a natural scene and figuration-related literature were looked into, and for figuring a natural scene on the basis of the results, the character of the topography of rice terraces was divided into 9 items as follows by generalizing the inspiration obtained from the natural scenic character and spatial character of rice terraces represented from the topography: (1) Inclination showing the degree of the slope of rice terraces, (2) The bending showed by unevenness of the edge line of rice terraces, (3) The degree of parallelism of the up-and-down edge line, (4) The size of the width of the section of each rice terrace, (5) The area of the total rice terraces, (6) Step gap that indicates the difference of high and low of the up-and-down small rice terraces, (7) Figuration as an image represented by the external form of the total rice terraces, (8) Naturalness and artificiality kept by the total scene, (9) Softness of cornerstones or soil that forms small rice terraces, an atmosphere produced by the total scenes, etc. The results of analysis made through GIS, with rice terraces of Gyeongnam Namhae, Sancheong and Hamyang Area as the target land, are as follows. First, the steeper the inclination is, the higher the step difference of cornerstones becomes, and the steeper the inclination, the narrower the area and width become, so that it could be known that, in rice terraces, inclination is proportional to step difference and the area is inversely proportional to the width. Second, it is considered that line showed in rice terraces, area elements and reiteration, repeated changes, and changes in the scene affected by the surrounding environment including those according to season can be converted into a variety of images according to an individual disposition. Third, it was decided that it is possible to figure repetitive composition and directivity, motility, order and change, etc. into a common type drawn from each target land. This paper, as a study of basic materials for expressing figuration in an environment field, investigated and analyzed the surrounding environment of the target land, and is significant in that it attempted the possibility of being able to generalize the environmental beauty of the target land as one figurative element. More precise studies are expected to be made later.

A Scenery Word of Pine Tree Extracted in Choi Myoung Hee's Novel 『Honbul』 (최명희의 소설 『혼불』에서 추출한 소나무의 경관언어)

  • Rho, Jae-Hyun;Kim, Hwa-Ok;Park, Yool-Jin
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.32 no.4
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    • pp.61-72
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    • 2014
  • Throughout analyzing and construing the words, contexts, and expressive languages used for depicting the pine tree in the novel "Honbul" written by Choi, Myung-Hee the symbolism of the pine and folksy languages used for scenery can be condensed as written below: First, it is explicit that the scenery-words for illustrating the pine tree in "Honbul" are emerged through diverse means methods and expressions. Namely, the reference forms of the pine tree and the expressive means of utilizing words portrays the use of the pine are various and subdivided. Second, the scenery-words found in vocabularies and the contexts of "Honbul" imply various symbolic representation. They not only perform to describe inherent image and symbolism of the pine, but they work for reifying the image of "Honbul" in the narrative structure in "Honbul" as being intrinsic scenery-word. Third, the scenery-words used for expressing aesthetics emerge as synesthetic expressions through the linear beauty and the texture of the pine as well as through five-senses. Forth, on the basis of the inherent symbolism and the image of the pine, the landscape of the background described in "Honbul" deems as a symbolic backdrop. As with then narrative structure of the novel, the pine tree performs as a mediation of the heaven and the earth, god and man, as well as the sacred and the secular. Fifth, scenery-words used for depicting the pine tree are a symbol that represents the spirit and emotion of the character in the novel. Moreover, it is a tool for pursuing the personification of the nature, the deification of the object, and the cosmos of the space. It is also utilized as a device that definitize the ideational image applied to express the landscape of the background of the novel. As mentioned above, the expressions, vocabularies and textures about pine tree represented from "Honbul" are expected to be the beginning of understanding the landscape-images and landscape-languages of pine in not only the setting for this novels, Namwon but also the entire districts of Korea.

A Study on Hermann Fürst Pücker-Muskau's landscape gardening theory focused on its development process and meanings (헤르만 F. 폰 퓌클러-무스카우(Hermann Fürst von Pückler-Muskau)의 풍경식 정원론의 형성과정과 의미에 관한 연구)

  • Zoh, Kyung-Jin
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.32 no.3
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    • pp.69-81
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    • 2014
  • Herman $F{\ddot{u}}rst\;P{\ddot{u}}ckler-Muskau$ is one of important figures in German landscape architecture who designed both Muskau Park and Branitz Park and published garden book Andeutungen ${\ddot{u}}ber$ Landschaftgartenerei (Hints on Landscape Gardening) in 1834. He was a German nobleman who governed Muskau estates while working as both a writer and a landscape gardener. German landscape gardening was grounded on Romanticism, which was represented in diverse ways such as the reconciliation between man and nature, the liberation of reason, and the pursuit of liberty. The intellectuals came to have an interest on landscape gardening since the garden carried the cultural connotation such as the idealized epitome of nature. This study is to investigate how his idea of landscape gardening had been developed through his personal life and social background and to find out his landscape gardening theory and its unique gardening techniques. Finally, the inventive aspect of his garden theory and contemporary significances in practices were discussed. $P{\ddot{u}}cklers^{\prime}$ personal experience and social background provide us to understand the idea of garden. First, there was a mixture between reality and fantasy in his garden theory. It was due to the influence of Romanticism and literary garden. Second, his gardening mentality and technique were influenced by the late 18th century English garden practices, which emphasized the expressive aspects. Third, $P{\ddot{u}}cklers^{\prime}$ inner disposition and personal experience were represented in his garden design. Fourth, the intention of creating landscape garden for the local people might be a self realization of his contradictory characters between falling nobleman and liberal social leader. The significant value of $P{\ddot{u}}ckler^{\prime}s$ garden idea might be closely related in the dual nature of humanistic garden tradition and garden practice for social agenda. Therefore, his garden idea pursued of the comprehensive landscape strategies toward ideal communities and ethical spirits while concerning ecological, social, economic sustainable development of the region. Furthermore, his landscape gardening aims at the total landscape encompassing garden to region as well as the Gesamtkunst combing the beautiful with the useful. $P{\ddot{u}}ckler^{\prime}s$ holistic attitude gives us fresh insights and new directions to contemporary landscape theory and practice.

Interpretation of C.C.L.Hirschfeld's Theory of Garden Art in Contemporary Meaning and Its Significance (히르시펠트(C.C.L.Hirschfeld) 정원예술론의 의미와 가치의 현대적 해석)

  • Zoh, Kyung-Jin
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.32 no.3
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    • pp.58-68
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    • 2014
  • Christian Cay Lorenz Hirschfeld is often regarded as 'a father of landscape garden art.' He was an aesthetics professor and garden theoretician in the $18^{th}$ century. He put forth the most comprehensive garden theory book in five volumes between 1779 and 1785. His book, Theorie der Gartenkunst, was translated and widely circulated in his contemporary. The book, which dealt with diverse aspects of garden art such as history, design, material, and type, urged to promote the prevalence of landscape garden in European continents as well as in Germany. However, there have scarcely been discourses in the Hirschfeld's garden theory. This essay aims to review Hirschfeld's garden thoughts in his book critically and to reinterpret some issues in the contemporary landscape theory and practice. Hirschfeldian theory was the product of $18^{th}$ century German Enlightenment and romanticism. At that time, Nature was regarded as divine realm. There was a German affinity with natural world. The spread of reading culture and the fashion of travel literature were another background of the success of his garden literature. Several issues in Hirschfeld garden theory will discussed here. First, privileging garden art was the most significant contribution in his theory. He emphasized that garden art was the most advanced art form among all art genres. Second, garden art was grounded on the mimesis of nature. The ambiguous relationship between nature and art still existed in garden making. However, garden art can be flourished when utilizing the potency of nature in itself. Third, there was the association between the image and the idea in experiencing the garden. Some garden scenes stimulated the related emotional responses such as cheerful and merry, softly melancholic, romantic, solemn etc. Fourth, the movement was the essential aspect of garden art. Motion and emotion are come together in garden experience. To represent the landscape garden style in suitable way, the sketch or image seems to be preferable than the plans and views. Finally, garden art was composing of not only the physical space but also the spirit of place. He maintained the garden art as hortus moralis should be a social metaphor. Hirschfeldian garden theory has often been criticized as the lack of practical power and the old fashioned idea. However, his theory influenced on formulating the idea of public park in $19^{th}$ century. Moreover, there are still some visionary aspects of his theory such as the reevaluation of garden art, the emphasis of locality and the introduction of Mittelweg idea. Recently, gardening culture are prevalent in various realms of art and life. Hirschfeld's garden theory as humanistic landscape theory can provide us some insights in the contemporary practices.

The Infertility Characteristics of Patients in the Obstetrics and Gynecology Specialized Hospital and Effect of Pregnancy on the Type of Assisted Reproductive Technology (산부인과 전문병원 내원환자의 난임 특성과 보조생식술 유형이 임신에 미치는 영향)

  • Kim, Yun-Jeong;Hwang, Byung-Deog
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.17 no.8
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    • pp.318-326
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    • 2016
  • This study was conducted to identify characteristics observed by staff during infertility treatment, and to analyze the relationship between the result of the treatment according to the ART infertility characteristics. In cooperation with an Obstetrics and Gynecology Hospital in Ulsan, data were collected from 344 people receiving infertility treatment from 2012-1013 and evaluated by cross-analysis, logistic regression analysis, and the ${\chi}^2$ test. Age 30 subjects (72.1%), no disease (70.9%), and no birth children (77.0%) were most common among patients. Causes of infertility factor is the higher the age, followed by uterine factors, ovarian factors were the lower the age.Were assisted reproduction are IUI (51.5%), IVF (23.0%), IUI + IVF (25.6%), assisted reproduction were age (p<.013) infertility period (p<.014), abortion Experience (p<.008) it was not statistically significant. ART pregnancies result was 34.9%, IUI was 49.2%, IVF was 50.8%. The average number of successful IVF treatment was 1.64, while it was 1.36 for IVF. IVF is 0.28 times lower than the IUI. Thus, low in order to increase the success rate of pregnancy according to the assisted reproduction age, nanim period is short, and if you do not have birth children choose artificial fertilization, and high age, IVF If there are nanim period is longer and birth child treatment and you must choose. This study analyzed all subjects who underwent fertility treatment to have research significance. However, it is difficult to generalize, locally called Sun City limits. If this one based on regional and national follow-up study of infertility therapist made it will help to prepare the way of effective treatment for infertility causes.

Chemical Properties of Olive and Bay Leaves (올리브 잎과 월계수 잎의 화학적 특성)

  • Lee, Ok-Hwan;Lee, Hee-Bong;Lee, Junsoo;Son, Jong-Youn;Rhee, Seong-Kap;Kim, Hyun-Duk;Kim, Young-Chan;Lee, Boo-Yong
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.34 no.4
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    • pp.503-508
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    • 2005
  • The chemical properties of olive and bay leaves were investigated and analyzed to provide basic data for food materialization and processing. The moisture contents of olive and bay leaves were $3.95\%$ and $8.50\%$, respectively. The contents of crude protein, crude fat, crude ash and carbohydrates of olive leaf were $11.04\%,\;7.45\%,\;5.05\%\;and\;76.46\%$, respectively. And the contents of same those components of bay leaf were $7.23\%,\;7.21\%,\;3.72\%\;and\;81.84\%$, respectively. Glutamic acid $(1086.8\;mg\%)$and aspartic acid $(918.8\;mg\%)$ in olive leaf were major amino acids, glutamic acid $(621.2\;mg\%)$ and leucine $(558.6\;mg\%)$ in bay leaf were the major amino acids. The major free sugar of olive leaf was sucrose $(1.55\%)$. Whereas major free sugar of bay leaf was glucose $(1.54\%)$. Palmitic acid $(olive\;33.0\%,\;bay\;17.8\%)$ and linolenic acid $(olive\;31.1\%,\;bay\;35.2\%)$ were major fatty acid in crude fat of both olive leaf and bay leaf. The Ca contents were the highest in olive leaf $(929.6\;mg\%)$and bay leaf $(836.2\;mg\%)$. Vitamin A contents of olive and bay leaves were 5.10 mg/100 g and 6.49 mg/100 g, respectively. Vitamin C contents of olive and bay leaves were 36.64 mg/100 g and 13.86 mg/100 g, respectively. But vitamin $B_6$ and $B_{12}$ were not detected.

Analysis of Functional Constituents of Mulberries (Morus alba L.) Cultivated in a Greenhouse and Open Field during Maturation (시설 및 노지 재배 오디의 숙기에 따른 기능성 성분 함량 분석)

  • Kim, Ha Yun;Lee, Ji Young;Hwang, In Guk;Han, Hye Min;Park, Bo Ram;Han, Gui Jung;Park, Jong Tae
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.44 no.10
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    • pp.1588-1593
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    • 2015
  • Contents of phenolic acids, flavonoids, and anthocyanins of mulberries (Morus alba L.) cultivated in a greenhouse (GH) and open field (OF) were evaluated by HPLC during maturation. In the case of phenolic acids, caffeic acid ($96.37{\sim}824.00{\mu}g/g$), coumaric acid ($19.45{\sim}68.23{\mu}g/g$), ferulic acid ($4.50{\sim}18.66{\mu}g/g$), and sinapic acid ($15.61{\sim}29.27{\mu}g/g$) were detected. The major phenolic acid was caffeic acid, and its content increased in the initial stage and decreased in the last stage. The phenolic acid content of OF mulberries was higher than that of GH mulberries. Contents of two major flavonoids, quercetin, and kaempferol, were $44.17{\sim}1,661.73{\mu}g/g$ and $108.67{\sim}360.20{\mu}g/g$, respectively. Quercetin content decreased with maturation stage, whereas kaempferol content remained constant in GH mulberries but increased in OF mulberries. In the case of cultivation methods, quercetin content of OF mulberries was higher than that of GH mulberries. Contents of cyanidin, delphinidin, malvidin, and pelargonidin were $30.43{\sim}6,443.88{\mu}g/g$, $0{\sim}52.10{\mu}g/g$, $1.06{\sim}1,650{\mu}g/g$, and $1.92{\sim}401.97{\mu}g/g$, respectively. Anthocyanin content increased with maturation stage, and anthocyanin content of OF mulberries was higher than that of GH mulberries. OF mulberries in the last stage of maturation had higher contents of functional substances than other conditions.