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A Study on the Documentation Method of Intangible Cultural Heritage and Training Center (무형문화유산 기록화와 전수교육관에 대한 연구)

  • Kim, Ji-hee;Lee, Young-hak
    • The Korean Journal of Archival Studies
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    • no.56
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    • pp.147-182
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    • 2018
  • Intangible cultural heritage is formless. It's of importance to preserve heritage in line with society drastically being transformed. It's passed down by human being. It is, on the other hand, impossible to preserve intangible cultural heritage solely based on memory, for it's changed in succession. Thus, it be archived to pass down. This study investigated on the state of affair related with Intangible cultural heritage documentations, examined the shortages thereupon. Furthermore, Training center should be in charge of documentation for a solution. This will provide an opportunity to overcome the limitations attributed to the top-down documentation system by central administrative organ, to open up the possibility of viewpoint of different successors, organizations. In addition to that, Intangible cultural heritage documents should be of different aspects of community history. Features of Intangible cultural heritages, which are convergent to the Regionality, tendency of variation, transmission, can be magnified when documentating. Finally, Training center is going to play a major role being vitalised. The record management of intangible cultural heritage, institutions and policies about Intangible cultural heritage have been highly complicated since National Intangible Heritage Center opened and the law on Intangible cultural heritage enacted with its recognition attracted. Therewith this study wishes to see a cornerstone of records on intangible cultural heritage by laying stress on training center in which educations and pass-down of intangible cultural heritage are lively achieved.

Low-Voltage EM(Elasto-Magnetic) Sensing Technique for Tensile Force Management of PSC(Prestressed Concrete) Internal Tendon (PSC 내부 텐던의 긴장력 관리를 위한 저전압 EM 센싱 기법)

  • Park, Jihwan;Kim, Junkyeong;Eum, Ki-Young;Park, Seunghee
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.32 no.2
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    • pp.87-92
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    • 2019
  • In this paper, we have verified a low-voltage EM(elasto-magnetic) sensing technique for tensile force management of PSC(prestressed concrete) internal tendon in order to apply the technique to actual construction sites where stable power supply is difficult. From observation of past domestic and overseas PSC structural accident cases, it was found that PS tension is very important to maintain structural stability. In this paper, we have tried to measure the tensile force from a magnetic hysteresis curve through EM sensors according to voltage value by using relation between magnetostriction and stress of ferromagnetic material based on elastic-magnetic theory. For this purpose, EM sensor of double cylindrical coil type was fabricated and tensile force test equipment for PS tendon using hydraulic tensioning device was constructed. The experiment was conducted to confirm relationship between changes of permeability and tensile force from the measurement results of the maximum / minimum voltage amount. The change of magnetic hysteresis curve with magnitude of tensile force was also measured by reducing amount of voltage step by step. As a result, the slope of estimation equation in accordance with magnitude of magnetic field decreases with the voltage reduction. But it was confirmed a similar pattern of change of magnetic permeability for the magnetic hysteresis loop. So, in this study, it is considered that it is possible to manage the tensions of PSC internal tendon using EM sensing technique in low-voltage state.

Drying seaweeds using hybrid hot water Goodle dryer (HHGD): comparison with freeze-dryer in chemical composition and antioxidant activity

  • Nagahawatta, D.P.;Asanka Sanjeewa, K.K.;Jayawardena, Thilina U.;Kim, Hyun-Soo;Yang, Hye-Won;Jiang, Yunfei;Je, Jun-Geon;Lee, Tae-Ki;Jeon, You-Jin
    • Fisheries and Aquatic Sciences
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    • v.24 no.1
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    • pp.19-31
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    • 2021
  • Seaweeds are a potential source of minerals, essential amino acids, fatty acids, proteins, and various bioactive compounds such as antioxidants. The higher water content of seaweeds reduces the shelf life and this requires the appropriate drying method. The drying conditions play a major role in the conservation of nutrient composition in dried seaweeds. In recent years, the seaweed industry has used many different drying methods with advantages and limitations. Hybrid hot-water Goodle dryer (HHGD) which is a special dryer mixed with hot-water and a Korean traditional heating system (Goodlejang) might be a solution to avoid these limitations. The present study evaluated the effect of drying conditions in HHGD on nutrient composition and bioactivities of brown seaweeds. Moreover, freeze-dryer (FD) and HHGD were employed in this study to compare the dried outputs obtained from four brown seaweed species. The present study aims to evaluate the effect of the hybrid hot-water Goodle drying method (HHGDM) on the nutritional composition and antioxidant activity of dried seaweeds. AOAC standard methods were used to analyze the proximate composition of dried samples and their 70% ethanol extract. The intracellular and extracellular antioxidant activities were evaluated using Vero cells and electron spin resonance (ESR) spectrometer respectively. High performance liquid chromatography, apoptotic body formation, and in-vivo experiments were used for further confirmation of the quality of dried output. The proximate composition results obtained from drying in HHGD and FD did not exhibit any significant difference. Moreover, the seaweed extracts from the dried seaweeds by HHGD and FD dryings were also not different and both significantly down-regulated in-vivo and in-vitro oxidative stress. Furthermore, the high performance liquid chromatography results revealed that the two dryers did not make the major peaks different in the chromatograms. Freeze-drying method (FDM) provides elevated quality for dried output, but there are limitations such as high cost and low capacity. The results from a novel HHGD did not provide any significant difference with the results in FD and expressed a potential to avoid the limitations in FD. Overall, these findings solidified the applicability of HHGD over FD.

Axial Compression of Stub Columns for Concrete-filled Square Steel Tubes (일축 압축력을 받는 콘크리트충전 각형강관 단주의 구조적 거동)

  • Yoo, Yeong-Chan
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.22 no.2
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    • pp.617-624
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    • 2021
  • Concrete-filled steel tubular columns can improve the strength and deformation capacity of structures, thereby enabling the development of efficient structures. The Korean design standard (KDS41) regarding concrete-filled steel tubular structures, established by the architectural institute of Korea in 2005, was revised in 2009 and 2016. The objective was to understand the compressive strengths and deformation capacity of stub columns for concrete-filled square steel tubes under uniaxial compression and validate the KDS41's standard code for necessary corrections. Experiments were conducted on 26 specimens with parameters, such as the width-thickness ratio of cold-formed square tubes. The following values of the stub columns for concrete-filled square steel tubes were obtained: compressive strengths, relationship between the axial load and axial displacement, and failure modes. An analysis of these results enabled an understanding of the concrete-filled effect and the influence of the wide-thickness ratio. The compressive strengths of filled concrete saw a 9% increase compared to a state of uniaxial stress, which must be noted in a future edition of KDS41. After benchmarking the results regarding square steel tubes generated by cold forming to the guidelines provided by the KDS41, the KDS41's value of 2.26 for the limiting width-to-thickness ratio for the compact section was found to be inflated. With a safety concern, this paper proposes a more conservative value of 1.35.

The character of teachers'and liberal teacher education (교사의 인성과 교양적 교사교육)

  • chung, Yun-Kyoung
    • (The)Korea Educational Review
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    • v.23 no.4
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    • pp.53-77
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    • 2017
  • This paper suggests that the meaning and the direction of character education should be understood and approached from a point of view which human formation is regarded as the essence of education. The best way of approach to the character education with this point of view could start from the teachers' character, because teachers are key actors for character formation of students. This study therefore places strong emphasis on the importance of teachers' character and suggesting liberal education, as a key solution, its aim is raising and developing the whole human being. The purpose of this study is to explore the possibility of liberal teacher education. With this purpose of study, the author argues the moral dimension of teaching and the importance of the teachers' role as a character builder in ch.II. In ch.III, the present state of teachers' character education is examined and is argued the necessity of liberal perspective for teacher education to stress the character formation of teachers. The liberal teacher education means that the teacher education is integrated into the quality of liberal education which emphasizes the whole human formation, transformation of personality and critical reflection for human formation. The ch. IV contains exploration of the possibility of liberal teacher education by discussing the compatibility between liberal education and vocational education. Furthermore, it covers how teacher education can reflect the quality of liberal education on the aim of teaching, contents and methods of teacher education concretely.

Martin Buber's Religious Socialism and Education (부버의 종교적 사회주의와 교육)

  • Kwak, Taejin;Kang, Sun-Bo
    • (The)Korea Educational Review
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    • v.22 no.3
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    • pp.169-192
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    • 2016
  • The purpose of this study is to investigate the relations between religious socialism and education of Martin Buber(1878~1965), a theistic existentialist. Buber suggested religious socialism as an alternative to modern capitalist society which has many problems. Buber's religious socialism is based on the communitarianism of Hasidism. Buber considered 'true' socialism must be based on decentralized associations, not based on centralized state apparatuses. For establishing this kind of socialism, human will and mind are the most important. Thus, education takes a very important role in the process of social transformation. According to Buber, education and pedagogy should contribute to overcoming modern society's problems by pursuing the construction of community(true socialist society). For Buber, education for individuals' character and education for building community are not separated but combined. That is, although education takes a main role in the social transformation, it should not be considered just as an instrument for the social transformation. This is the main distinction between Buber's thought and other key socialists' thoughts on social transformation and education, because many of socialists who stress the role of education in the process of social transformation, tend to regard education as an instrument for the social transformation. According to Buber, education can contribute to social transformation without being an instrument for the social transformation. These ideas of Buber on religious socialism and education have important implications for educators and educationalists who hope education contributes to solving problems of modern society.

Structural Behavior of Reinforced Concrete Members Subjected to Axial and Blast Loads Using Nonlinear Dynamic Analysis (비선형 동적해석을 이용한 축하중과 폭발하중을 동시에 받는 철근콘크리트 부재의 구조 거동 분석)

  • Lee, Seung-Hoon;Kim, Han-Soo
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.35 no.3
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    • pp.141-148
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    • 2022
  • In this study, the structural behavior of reinforced concrete members under simultaneous axial and blast loads was analyzed. Nonlinear dynamic analysis verification was performed using the experimental data of panels under fundamental blast load as well as those of reinforced concrete columns subjected to axial and blast loads. Because Autodyn is a program designed only for dynamic analysis, an analysis process is devised to simulate the initial stress state of members under static loads, such as axial loads. A total of 80 nonlinear dynamic finite element analysis procedures were conducted by selecting parameters corresponding to axial load ratios and scaled distances ranging 0%~70% and 1.1~2.0 (depending on the equivalent of TNT), respectively. The structural behavior was compared and analyzed with the corresponding degree of damage and maximum lateral displacement through the changes in axial load ratio and scaled distance. The results show that the maximum lateral displacement decreases due to the increase in column stiffness under axial loads. In view of the foregoing, the formulated analysis process is anticipated to be used in developing blast-resistant design models where structural behavior can be classified into three areas considering axial load ratios of 10%~30%, 30%~50%, and more than 50%.

Folding Analysis of Paper Structure and Estimation of Optimal Collision Conditions for Reversal (종이구조물의 접기해석과 반전을 위한 최적충돌조건의 산정)

  • Gye-Hee Lee
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.36 no.4
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    • pp.213-220
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    • 2023
  • This paper presents a model simulating the folding process and collision dynamics of "ddakji", a traditional Korean game played using paper tiles (which are also referred to as ddakji). The model uses two A4 sheets as the base materials for ddakji. The folding process involves a series of boundary conditions that transform the wing part of the paper structure into a twisted configuration. A rigid plate boundary condition is also adopted for squeezing, establishing the shape and stress state of the game-ready ddakji through dynamic relaxation analysis. The gaming process analysis involves a forced displacement of the striking ddakji to a predetermined collision position. Collision analysis then follows at a given speed, with the objective of overturning the struck ddakji--a winning condition. A genetic algorithm-based optimization analysis identifies the optimal collision conditions that result in the overturning of the struck ddakji. For efficiency, the collision analysis is divided into two stages, with the second stage carried out only if the first stage predicts a possible overturn. The fitness function for the genetic algorithm during the first stage is the direction cosine of the struck ddakji, whereas in the second stage, it is the inverse of the speed, thus targeting the lowest overall collision speed. Consequently, this analysis provides optimal collision conditions for various compression thicknesses.

Analysis on the Rigid Connections of the Drilled Shaft with the Cap for Multiple Pile Foundations (현장타설말뚝을 적용한 다주식 기초에서 말뚝과 캡의 강결합에 대한 분석)

  • Cho, Sung-Min
    • Journal of the Korean Geotechnical Society
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    • v.24 no.7
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    • pp.61-73
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    • 2008
  • Piles of a bridge pier are connected with the column through the pile cap (footing). Behavior of the pile foundation can be different according to the connection method between piles and the pile cap. Connection methods between pile heads and the pile cap are divided into two groups : rigid connections and hinge connections. Domestic design code has been specified to use rigid connection method for the highway bridge. In the rigid connection method, maximum bending moment of a pile occurs at the pile head and this helps the pile to prevent the excessive displacement. Rigid methods are also good to improve the seismic performance. However, some specifications prescribe that conservative results through investigations of both the fixed-head condition and the free-head condition should be reflected in the design. This statement may induce an over-estimated design for the bridge which has high-quality structures with casing covered drilled shafts and the PC-house contained pile cap. Because the assumption of free-head conditions (hinge connections) is unreal for the elevated pile cap system with multiple piles of the long span sea-crossing bridges. On the other hand, elastic displacement method to evaluate the pile reactions under the pile cap is not suitable for this type of bridges due to impractical assumptions. So, full modeling techniques which analyze the superstructure and the substructure simultaneously should be performed. Loads and stress state of the large diameter drilled shaft and the pile cap for Incheon Bridge which will be the longest bridge of Korea were investigated through the full modeling for rigid connection conditions.

Cannabidiol Inhibits Lipogenesis by Regulating Akt/AMPK-SREBP-1 Pathway in Sebocytes (피지세포에서 Akt/AMPK-SREBP-1 경로를 통한 CBD의 피지 합성 억제 효능)

  • Yoon Gyung Kwon;Ji Young Yoon;Hanon Lee;Dong Hyo Kim;Jun Hyo Lee;Diane M Thiboutot;Dae Hun Suh;Byoung Jun Park
    • Journal of Life Science
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    • v.33 no.4
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    • pp.343-348
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    • 2023
  • Acne is one of the most common skin diseases, mainly occurring in adolescence. The pathophysiology of acne involves not only hormonal, genetic and environmental factors, but also other factors including hyperseborrhea, inflammation, over-keratinization of follicular keratinocytes and overgrowth of Cutibacterium acnes (C. acnes). Cannabidiol (CBD) is known to relieve pain, stress and inflammation. Moreover, cannabis extracts containing CBD have been reported to be effective in treating acne. However, the therapeutic effect of CBD on acne remains unclear. Therefore, this study aimed to investigate the effect and mechanism of CBD on lipogenesis in SEB-1 sebocytes. We treated sebocytes with CBD and found that it not only inhibited lipid synthesis, but also inhibited cell proliferation by inducing apoptosis. We then demonstrated that sterol response element-binding protein-1 (SREBP-1) mediates the inhibitory effect of CBD on lipogenesis. Furthermore, Akt and adenosine monophosphate-activated protein kinase (AMPK), upstream regulators of SREBP-1, were regulated by CBD treatment. Taken together, our studies demonstrate that CBD inhibits adipogenesis by regulating the Akt/AMPK-SREBP-1 signaling pathway, providing potential for use as a therapeutic agent for acne. Further research is needed to confirm the effect of CBD on inflammation caused by hyperkeratosis, which will increase the possibility of using CBD for acne treatment.