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The Leadership in Korean Confucianism and its Modern Characteristics : Chíjìng(持敬) to Zhìzhì(至治), the Leadership Wisdom (한국 유학의 리더십과 그 현대적 특징 - 지경(持敬)에서 지치(至治)로, 지혜의 리더십 -)

  • Kim, Dong-Min
    • The Journal of Korean Philosophical History
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    • no.23
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    • pp.7-65
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    • 2008
  • The object of this essay is to apply the Leadership Theory, current interest in Asian Philosophy, to Korean appliance. This is to associate contemporary Leadership Theory with Chosun Confucianism in order to discover the Korean Leadership Prototype, and seek the possibility of applying it for modern usage. The essay uses two analysis models. The tools used for the methodology consists of the personal characteristics of the leader as one axis and ruling out the roles in order to develop the discussion as the other axis. First axis is the process of the leader setting the identity and strengthening the ability to successfully deploy his/her leadership. The second axis is comprised of four specific fields where the leadership is deployed. The four sectors are Self Sector, Relationship Sector, Team Sector and Community Sector. Core values of each sector have been set up and specific competences have been presented. In the Self Sector, $zh{\grave{i}}x{\bar{i}}n$(治心) and $ch{\acute{i}}j{\grave{i}}ng$(持敬) have been set as core values and $l{\grave{i}}zh{\grave{i}}$(立志) and $sh{\acute{i}}x{\bar{i}}n$(實心) as their competences. In the Relationship Sector and Team Sector, circumstances(時宜) and $sh{\acute{i}}sh{\grave{i}}g{\bar{e}}ngzh{\bar{a}}ng$(實事更張) were set as core values, accordingly. Lastly for the Community sector, the core value, 'Ideal Leader and the Visions of and Ideal Community', was conceptualized as '$m{\grave{ui}}m{\acute{i}}nzh{\grave{i}}zh{\grave{i}}$(牧民至治)'. The leadership is then expanded from the Self Sector to the final stage through its processes. Through this research, it can be found out that the Korean Leadership Model is not rigid to just cover a specific point in time or situation, but embraces many contemporary leadership concepts, thus having the characteristics of a comprehensive leadership theory.

A Study on the Original Landscape for the Restoration and Maintenance of Buyongjeong and Juhamnu Areas in Changdeokgung Palace (창덕궁 부용정과 주합루 권역의 복원정비를 위한 원형 경관 고찰)

  • Oh, Jun-Young;Yang, Ki-Cheol
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.39 no.4
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    • pp.24-37
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    • 2021
  • This study was conducted to newly examine the original landscape of Buyongjeong(芙蓉亭) and Juhamnu(宙合樓) areas in Changdeokgung Palace(昌德宮), focusing on the modern period including the Korean Empire, and to derive useful research results for restoration and maintenance in the future. The study results can be summarized as follows. First, the artificial island in Buyongji(芙蓉池) was originally made up of a straight layer using well-trimmed processed stone. However, during the maintenance work in the 1960s and 1970s, the artificial island in Buyongji was transformed into a mixture of natural and processed stones. The handrail installed on the upper part of the artificial island in Buyongji is a unique facility that is hard to find similar cases. The handrail existed even during the Korean Empire, but was completely destroyed during the Japanese colonial period. Second, Chwibyeong(翠屛), which is currently located on the left and right of Eosumun(魚水門), is the result of a reproduction based on Northern bamboo in 2008. Although there is a view that sees the plant material of Eosumun Chwibyeong as Rigid-branch yew, the specific species is still vague. Looking at the related data and circumstances from various angles, at least in the modern era, it is highly probable that the Eosumun Chwibyeong was made of Chinese juniper like Donggwanwangmyo Shrine(東關王廟) and Guncheongung(乾淸宮) in Gyeongbokgung Palace(景福宮). Third, the backyard of Juhamnu was a space with no dense trees on top of a stone staircase-shaped structure. The stone stairway in the backyard of Juhamnu was maintained in a relatively open form, and it also functioned as a space to pass through the surrounding buildings. However, as large-scale planting work was carried out in the late 1980s, the backyard of Juhamnu was maintained in the same shape as a Terraced Flower Bed, and it was transformed into a closed space where many flowering plants were planted. Fourth, Yeonghwadang Namhaenggak(暎花堂 南行閣), which had a library function like Gyujanggak(奎章閣) and Gaeyuwa(皆有窩), was destroyed in the late 1900s and was difficult to understand in its original form. Based on modern photographs and sketch materials, this study confirmed the arrangement axis of Yeonghwadang Namhaenggak, and confirmed the shape and design features of the building. In addition, an estimated restoration map referring to 「Donggwoldo(東闕圖)」 and 「Donggwoldohyung(東闕圓形)」 was presented for the construction of basic data.

Structural Behavior Evaluation of NRC Beam-Column Connections (NRC 보-기둥 접합부의 구조적 거동 평가)

  • Jeon, Ji-Hwan;Lee, Sang-Yun;Kim, Seung-Hun
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.26 no.1
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    • pp.73-80
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    • 2022
  • In this study, details of NRC beam-column connections were developed in which beam and columns pre-assembled in factories using steel angles were bolted on site. The developed joint details are NRC-J type and NRC-JD type. NRC-J type is a method of tensile joining with TS bolts to the side and lower surfaces of the side plate of the NRC column and the end plate of the NRC beam. NRC-JD type has a rigid joint with high-strength bolts between the NRC beam and the side of the NRC column for shear, and with lap splices of reinforcing bar penetrating the joint and the beam main reinforcement for bending. For the seismic performance evaluation of the joint, three specimens were tested: an NRC-J specimen and NRC-JD specimen with NRC beam-column joint details, and an RC-J specimen with RC beam-column joint detail. As a result of the repeated lateral load test, the final failure mode of all specimens was the bending fracture of the beam at the beam-column interface. Compared to the RC-J specimen, the maximum strength of the specimen by the positive force was 10.1% and 29.6% higher in the NRC-J specimen and the NRC-JD specimen, respectively. Both NRC joint details were evaluated to secure ductility of 0.03 rad or more, the minimum total inter-story displacement angle required for the composite intermediate moment frame according to the KDS standard (KDS 41 31 00). At the slope by relative storey displacemet of 5.7%, the NRC-J specimen and the NRC-JD specimen had about 34.8% and 61.1% greater cumulative energy dissipation capacity than the RC specimen. The experimental strength of the NRC beam-column connection was evaluated to be 30% to 53% greater than the theoretical strength according to the KDS standard formula, and the standard formula evaluated the joint performance as a safety side.

The Philosophical Status of Scientific Theories for Science Education (과학교육을 위한 과학이론의 철학적 위치)

  • Jun-Young, Oh;Eun-Ju, Lee
    • Journal of the Korean Society of Earth Science Education
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    • v.15 no.3
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    • pp.354-372
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    • 2022
  • The purpose of this study is to explore the philosophical position of various scientific theories based on the scientific worldviews for science education. In addition, it aims to expand science education, which has usually dealt with epistemology and methodology, to ontology, that is, to the problem of metaphysics. It can be said that there exists a physical realism, traditionally defined as a strong determinism of the metaphysical belief. That is fixed and unchanging objective scientific knowledge independent of our minds, which was established by Newton, Einstein and Schridinger. What can be seen in the natural laws of dynamics can be called 'mathematicization'. Einstein also shook the traditional views to some extent through the theory of relativity, but his theory was still close to traditional thinking. On the contrary, to escape from this rigid determinism, we need anthropomorphic concepts such as 'possibility' and 'chance'. It is a characteristic of the modern scientific worldviews that leads the change of scientific theory from a classically strong deterministic thought to a weak deterministic accidental accident, probability theory, and a naturalistic point of view. This can be said to correspond to Darwin's theory of evolution and quantum mechanics. We can have three types of epistemological worlds that justify this ontological worldviews. These are rationalism, empiricism and naturalism. In many cases, science education does not tell us what kind of metaphysical beliefs the scientific theories we deal with in the field of education are based on. Also, science education focuses only on the understanding of scientific knowledge. However, it can be said that true knowledge can bring understanding only when it is connected to the knowledge of learned knowledge and the learner's own metaphysical belief in the world. Therefore, in the future, science education needs to connect various scientific theories based on scientific worldviews and philosophical position and present them to students.

4D Printing Materials for Soft Robots (소프트 로봇용 4D 프린팅 소재)

  • Sunhee Lee
    • Fashion & Textile Research Journal
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    • v.24 no.6
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    • pp.667-685
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    • 2022
  • This paper aims to investigate 4D printing materials for soft robots. 4D printing is a targeted evolution of the 3D printed structure in shape, property, and functionality. It is capable of self-assembly, multi-functionality, and self-repair. In addition, it is time-dependent, printer-independent, and predictable. The shape-shifting behaviors considered in 4D printing include folding, bending, twisting, linear or nonlinear expansion/contraction, surface curling, and generating surface topographical features. The shapes can shift from 1D to 1D, 1D to 2D, 2D to 2D, 1D to 3D, 2D to 3D, and 3D to 3D. In the 4D printing auxetic structure, the kinetiX is a cellular-based material design composed of rigid plates and elastic hinges. In pneumatic auxetics based on the kirigami structure, an inverse optimization method for designing and fabricating morphs three-dimensional shapes out of patterns laid out flat. When 4D printing material is molded into a deformable 3D structure, it can be applied to the exoskeleton material of soft robots such as upper and lower limbs, fingers, hands, toes, and feet. Research on 4D printing materials for soft robots is essential in developing smart clothing for healthcare in the textile and fashion industry.

Preparation of Silica Nanoparticles via Recycling of Silicon Sludge from Semiconductor Dicing Process and Electro-responsive Smart Fluid Application (반도체 다이싱 공정에서 발생하는 실리콘 슬러지를 재활용한 실리카 나노입자의 제조 및 전기감응형 유체로의 응용)

  • Yeon-Ryong Chu;Suk Jekal;Jiwon Kim;Ha-Yeong Kim;Chan-Gyo Kim;Minki Sa;Hyung Sub Sim;Chang-Min Yoon
    • Journal of the Korea Organic Resources Recycling Association
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    • v.31 no.3
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    • pp.15-25
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    • 2023
  • In this study, silicon sludge from semiconductor dicing process is recycled to fabricate silica nanoparticles, which are applied as dispersing materials for electro-responsive (ER) smart fluid. In specific, metal impurities are removed from silicon sludge by acid washing to obtain the high-purity silicon powder. And then, silica nanoparticles are synthesized by facile hydrothermal method employing the silicon powder as reactant material. To control the size of silica nanoparticles, the reaction time of hydrothermal method is varied as 8, 15, 20, and 30 hours are applied to control the size of silica nanoparticles. Sizes of silica nanoparticles are increased proportionally to the reaction time owing to the increased numbers of hydrolysis and condensation reactions. As-synthesized silica nanoparticles are prepared as electro-responsive smart fluids by dispersing into silicon oil. Silica nanoparticles synthesized by 30 hours of hydrothermal reaction (SiO2-H30) exhibit the highest shear stress of 21.4 Pa under an applied electric field strength of 3.0kV mm-1. Such enhancement in ER performance of SiO2-H30 among various silica nanoparticles are attribute to the reinforcing effect originated from the mixed particle size, which allowing the formation of rigid chain-like structures. Accordingly, this study successfully propose a recycling method of silicon sludge to synthesize silica nanoparticles and their derived ER fluids, which may suggest new possibility to ESG management emphasizing the eco-friendliness.

A Study on tradition of Nihonbuyo(日本舞踊) and the Imoto(家元) system (니혼부요(日本舞踊)의 전승과 이에모토(家元) 제도)

  • Nam, Sung-Ho
    • (The) Research of the performance art and culture
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    • no.40
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    • pp.71-109
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    • 2020
  • Nihonbuyo(日本舞踊), a typical traditional Japanese dance, began with kabuki dancing and formed many schools, and was managed by Iemoto system. Iemoto(家元) is the head family of a school of a traditional Japanese art. Iemoto(家元) existed after the establishment of the ancient family system, and it was established as a system during the modern feudal period. Especially in Nihon Buyo, the Iemoto system has developed greatly since the modern era. Iemoto System has has contributed greatly to the succession of traditional arts and has been considered one of the characteristics of Japanese society. Basically, Iemoto system considers it the best authority to pass on the skills of excellent teachers without any distortion. It has various forms depending on the field and the school, but it is an organization with a family structure similar to that of a family with Iemoto at the top. In this article, I examined the establishment and background of the Nihonbuyo and considered the succession of the fame and authority of Iemoto through the system of succession. There are so many schools in the Nihonbuyo world that it is said to be a school kingdom. These schools were divided into kabuki actors, choreographers, female entertainers, ChiutaMai dance(地唄舞) and new dance styles, and the aspect of the Iemoto system was examined through the background and characteristics of each school. While Iemoto system has a positive aspect of inheriting the tradition, there are also many negative criticisms in the art world, such as rigid organizational management, the products of feudal society, the power of Iemoto, and the stalemate of arts. Nevertheless, in a Japanese society that places importance on tradition, the landlady system will not disappear easily. In fact, today, when there are many different art genres in common, young dancers are starting to challenge themselves along with self-examination of Iemoto in order to make the best use of traditional art. We hope that through consideration of the Japanese housekeeping system, it will become a place where intangible cultural properties will be re-acknowledged.

Synthesis of Uniform Silica Nanoparticles using Tap, Industrial, and Stream water and Their Application to Electro-responsive Smart Fluid System (상수, 공업용수, 및 하천수를 활용한 균일한 실리카 나노입자 합성 및 전기감응형 스마트유체로의 응용)

  • Ha-Yeong Kim;Suk Jekal;Neunghi Lee;Minki Sa;Dong Hyun Kim;Min Sang Kim;Jiwon Kim;Chang-Min Yoon
    • Journal of the Korea Organic Resources Recycling Association
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    • v.31 no.1
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    • pp.47-56
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    • 2023
  • This study describes the successful synthesize strategy for the silica nanoparticles utilizing various water sources, including tap, industrial, and stream waters without using deionized water. Also, as-synthesized silica nanoparticles are employed as dispersive materials for the electro-responsive smart fluid application. Specifically, homogeneous silica nanoparticles with sizes of 500-700nm are successfully prepared in large scale at once (ca. 12.0 g) with the described experimental method and showing similar structural and chemical characteristics with silica nanoparticles synthesized using the deionized water. The size of silica nanoparticles are varied according to the ion conductivity differences of tap, industrial, stream water, and deionized water. The size of silica nanoparticles decresed with the increased ion conductivity, indicating the ion suppression of growth of silica nanoparticles. Moreover, as-synthesized silica nanoparticles from various water sources of electro-responsive characteristic are investigated by the smart fluid application. The smart fluids containing silica nanoparticles synthesized by tap, industrial, and stream water exhibited higher shear stress compared to the deionized water, owing to the more rigid fibril-like structures formed by the smaller silica nanoparticles. Conclusively, uniform silica nanoparticles from various water sources without any purification are able to successfully prepared without usage of deionized water and resulting silica nanoparticles manifested higher electro-responsive performance.

Analysis on dynamic numerical model of subsea railway tunnel considering various ground and seismic conditions (다양한 지반 및 지진하중 조건을 고려한 해저철도 터널의 동적 수치모델 분석)

  • Changwon Kwak;Jeongjun Park;Mintaek Yoo
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.25 no.6
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    • pp.583-603
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    • 2023
  • Recently, the advancement of mechanical tunnel boring machine (TBM) technology and the characteristics of subsea railway tunnels subjected to hydrostatic pressure have led to the widespread application of shield TBM methods in the design and construction of subsea railway tunnels. Subsea railway tunnels are exposed in a constant pore water pressure and are influenced by the amplification of seismic waves during earthquake. In particular, seismic loads acting on subsea railway tunnels under various ground conditions such as soft ground, soft soil-rock composite ground, and fractured zones can cause significant changes in tunnel displacement and stress, thereby affecting tunnel safety. Additionally, the dynamic response of the ground and tunnel varies based on seismic load parameters such as frequency characteristics, seismic waveform, and peak acceleration, adding complexity to the behavior of the ground-tunnel structure system. In this study, a finite difference method is employed to model the entire ground-tunnel structure system, considering hydrostatic pressure, for the investigation of dynamic behavior of subsea railway tunnel during earthquake. Since the key factors influencing the dynamic behavior during seismic events are ground conditions and seismic waves, six analysis cases are established based on virtual ground conditions: Case-1 with weathered soil, Case-2 with hard rock, Case-3 with a composite ground of soil and hard rock in the tunnel longitudinal direction, Case-4 with the tunnel passing through a narrow fault zone, Case-5 with a composite ground of soft soil and hard rock in the tunnel longitudinal direction, and Case-6 with the tunnel passing through a wide fractured zone. As a result, horizontal displacements due to earthquakes tend to increase with an increase in ground stiffness, however, the displacements tend to be restrained due to the confining effects of the ground and the rigid shield segments. On the contrary, peak compressive stress of segment significantly increases with weaker ground stiffness and the effects of displacement restrain contribute the increase of peak compressive stress of segment.

Analysis of the Effect of Corner Points and Image Resolution in a Mechanical Test Combining Digital Image Processing and Mesh-free Method (디지털 이미지 처리와 강형식 기반의 무요소법을 융합한 시험법의 모서리 점과 이미지 해상도의 영향 분석)

  • Junwon Park;Yeon-Suk Jeong;Young-Cheol Yoon
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.37 no.1
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    • pp.67-76
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    • 2024
  • In this paper, we present a DIP-MLS testing method that combines digital image processing with a rigid body-based MLS differencing approach to measure mechanical variables and analyze the impact of target location and image resolution. This method assesses the displacement of the target attached to the sample through digital image processing and allocates this displacement to the node displacement of the MLS differencing method, which solely employs nodes to calculate mechanical variables such as stress and strain of the studied object. We propose an effective method to measure the displacement of the target's center of gravity using digital image processing. The calculation of mechanical variables through the MLS differencing method, incorporating image-based target displacement, facilitates easy computation of mechanical variables at arbitrary positions without constraints from meshes or grids. This is achieved by acquiring the accurate displacement history of the test specimen and utilizing the displacement of tracking points with low rigidity. The developed testing method was validated by comparing the measurement results of the sensor with those of the DIP-MLS testing method in a three-point bending test of a rubber beam. Additionally, numerical analysis results simulated only by the MLS differencing method were compared, confirming that the developed method accurately reproduces the actual test and shows good agreement with numerical analysis results before significant deformation. Furthermore, we analyzed the effects of boundary points by applying 46 tracking points, including corner points, to the DIP-MLS testing method. This was compared with using only the internal points of the target, determining the optimal image resolution for this testing method. Through this, we demonstrated that the developed method efficiently addresses the limitations of direct experiments or existing mesh-based simulations. It also suggests that digitalization of the experimental-simulation process is achievable to a considerable extent.