• Title/Summary/Keyword: Element composition

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Modernization of Traditional Education for the Education of Humanity (인성교육을 위한 전통 유학교육의 현대화 방안 - 교육내용 및 교육방법을 중심으로 -)

  • Lee, Seung-Chul;Chi, Chun-Ho
    • The Journal of Korean Philosophical History
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    • no.57
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    • pp.183-207
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    • 2018
  • This article examines the implications of contemporary humanities education, which is raised by traditional education abroad, focusing on the contents of education and modernization of education methods. To this end, this article will cover the following topics. First, as a premise of discussion, we review the necessity of modernization of traditional education and the composition of traditional education element for modern reinterpretation. Second, I will examine the modernization of education contents through the modern education understanding of 'whole person' as a modernization plan of education contents for the traditional study abroad education and the modernization of education contents for strengthening the virtuous cycle of knowledge - practice. Third, we examine two aspects of modernization of education methods for traditional education abroad: strengthening of reflection ability through human formation and habituation through autonomous methods. Finally, briefly summarize the preceding discussion and suggest what future research should aim to do.

Study on the Compositional Characteristics of the PCS Coating Layer by Curing Treatment for the Protection of Graphite Mold Surface (흑연 금형 표면 보호용 PCS 코팅층의 열경화에 의한 조성비 조절 특성 연구)

  • Kim, Kyoung-Ho;Lee, Yoonjoo;Shin, Yun-Ji;Jeong, Seong-Min;Lee, Myung-Hyun;Bae, Si-Young
    • Journal of the Korean institute of surface engineering
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    • v.53 no.6
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    • pp.293-299
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    • 2020
  • The characteristics of the polycarbosilane (PCS)-based composite ceramic layer was studied by controlling the curing temperature. The stress at the interface of the graphite and SiOC composite layer was evaluated v ia finite element analysis. As a result, the tensile stress was released as the carbon ratio of the SiC decreases. In experiment, the SiOC layers were coated on the VDR graphite block by dip-coating process. It was revealed that the composition of Si and C was effectively adjusted depending on the curing temperature. As the solution-based process is employed, the surface roughness was reduced for the appropriate PCS curing temperature. Hence, it is expected that the cured SiOC layer can be utilized to reduce cracking and peeling of SiC ceramic composites on graphite mold by improving the interfacial stress and surface roughness.

Analysis of the effect of street green structure on PM2.5 in the walk space - Using microclimate simulation - (가로녹지 유형이 보행공간의 초미세먼지에 미치는 영향 분석 - 미기후 시뮬레이션을 활용하여 -)

  • Kim, Shin-Woo;Lee, Dong-Kun;Bae, Chae-Young
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.24 no.4
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    • pp.61-75
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    • 2021
  • Roadside greenery in the city is not only a means of reducing fine dust, but also an indispensable element of the city in various aspects such as improvement of urban thermal environment, noise reduction, ecosystem connectivity, and aesthetics. However, in studies dealing with the effect of reducing fine dust through trees in existing urban spaces, microscopic aspects such as the adsorption effect of plants were dealt with, structural changes such as the width of urban buildings and streets, and the presence or absence of trees, Impact studies that reflect the actual form of In this study, the effect of greenery composition applicable to urban space on PM2.5 was simulated through the microclimate epidemiologic model ENVI-met, and field measurements were performed in parallel to verify the results. In addition, by analyzing the results of fine dust background concentration, wind speed, and leaf area index, the sensitivity to major influencing variables was tested. As a result of the study, it was confirmed that the fine dust reduction effect was the highest in the case with a high planting amount, and the reduction effect was the greatest at a low background concentration. Based on this, the cost of planting street green areas and the effect of reducing PM2.5 were compared. The results of this study can contribute as a basis for considering the effect of pedestrian space on air quality when planning and designing street green spaces.

Effects of metal dopant content on mechanical properties of Ti-Cu-N films

  • Hyun S. Myung;Lee, Hyuk M.;Kim, Sang S.;Jeon G. Han
    • Proceedings of the Korean Institute of Surface Engineering Conference
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    • 2001.11a
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    • pp.37-37
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    • 2001
  • TiN coatings were applied for VarIOUS application fields, because of a good wear-resistance and a high hardness. Typically, TiN thin films show the hardness of 25GPa and friction coefficient of 0.6. However, in many field, one is looking for a more improved tool which has low friction coefficient and high wear resistance. The main motivation of this study is to characterize the influence of copper dopant content on TiN thin films. Ti-Cu-N thin films were deposited onto D2 steel substrates by PVD processing with various magnetron current densities (Cu contents). In this work, we synthesized titanium nitride films similar with reported typical titanium nitride films and synthesized Ti-Cu-N thin films with the addition of elemental copper which is measured improved hardness more than pure TiN films with copper content variables. This films has preferred oriented films of (111) direction. In addition, It was found that there is a strong correlation between content of various metal and film characteristics such as preferred orientation, grain size, hardness and friction coefficient and so, in future study, improved mechanical properties of TiN films can be controlled by change in target current density. The Ti-Cu-N film will show apparent hardness improvement and mechanical properties enhancement, when doping element is added onto TiN thin films. Film structure, chemical composition, mechanical properties were investigated by means of X-ray diffraction(XRD), scanning electron microscopy(SEM), transmission electron microscopy (TEM), energy dispersive spectroscopy(EDS), wear resistance tester and nanohardness tester.

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Bandgap Engineering in CZTSSe Thin Films via Controlling S/(S+Se) Ratio

  • Vijay C. Karade;Jun Sung Jang;Kuldeep Singh, Gour;Yeonwoo Park;Hyeonwook, Park;Jin Hyeok Kim;Jae Ho Yun
    • Current Photovoltaic Research
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    • v.11 no.3
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    • pp.67-74
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    • 2023
  • The earth-abundant element-based Cu2ZnSn(S,Se)4 (CZTSSe) thin film solar cells (TFSCs) have attracted greater attention in the photovoltaic (PV) community due to their rapid development in device power conversion efficiency (PCE) >13%. In the present work, we demonstrated the fine-tuning of the bandgap in the CZTSSe TFSCs by altering the sulfur (S) to the selenium (Se) chalcogenide ratio. To achieve this, the CZTSSe absorber layers are fabricated with different S/(S+Se) ratios from 0.02 to 0.08 of their weight percentage. Further compositional, morphological, and optoelectronic properties are studied using various characterization techniques. It is observed that the change in the S/(S+Se) ratios has minimal impact on the overall Cu/(Zn+Sn) composition ratio. In contrast, the S and Se content within the CZTSSe absorber layer gets altered with a change in the S/(S+Se) ratio. It also influences the overall absorber quality and gets worse at higher S/(S+Se). Furthermore, the device performance evaluated for similar CZTSSe TFSCs showed a linear increase and decrease in the open circuit voltage (Voc) and short circuit current density (Jsc) of the device with an increasing S/(S+Se) ratio. The external quantum efficiency (EQE) measured also exhibited a linear blue shift in absorption edge, increasing the bandgap from 1.056 eV to 1.228 eV, respectively.

A Study on the Academic Information Seeking Behavior of University Students to Improve Subject Guide: Focusing on C University (주제가이드 개선을 위한 대학생의 학술정보탐색행태 연구: C 대학을 중심으로)

  • Ahyeon Kim;Seungmin Lee
    • Journal of the Korean Society for information Management
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    • v.40 no.3
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    • pp.55-76
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    • 2023
  • This study analyzed academic information seeking behavior, focusing on university students, the main users of the university library, to derive considerations for the development and improvement of the subject guide of the university library. As a result of the analysis, university students highly evaluated their subjective information seeking ability, but it was found that it was difficult to set specific search terms. The purpose of using academic information is specific, and it has been shown that there is a tendency to perform all information search activities in one database. In addition, when selecting information resources, reliability, suitability, and recency are primarily taken into consideration. Awareness of university libraries and subject guides was generally low, but their reliability was found to be high. Based on this, it is necessary to consider the classification of information sources according to specific information seeking purposes, the composition of information resources, explanatory element technology related to information resource selection criteria, comprehensive database, topic keyword recommendation, library marketing, and close cooperation with internal institutions.

In-situ measurement of Ce concentration in high-temperature molten salts using acoustic-assisted laser-induced breakdown spectroscopy with gas protective layer

  • Yunu Lee;Seokjoo Yoon;Nayoung Kim;Dokyu Kang;Hyeongbin Kim;Wonseok Yang;Milos Burger;Igor Jovanovic;Sungyeol Choi
    • Nuclear Engineering and Technology
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    • v.54 no.12
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    • pp.4431-4440
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    • 2022
  • An advanced nuclear reactor based on molten salts including a molten salt reactor and pyroprocessing needs a sensitive monitoring system suitable for operation in harsh environments with limited access. Multi-element detection is challenging with the conventional technologies that are compatible with the in-situ operation; hence laser-induced breakdown spectroscopy (LIBS) has been investigated as a potential alternative. However, limited precision is a chronic problem with LIBS. We increased the precision of LIBS under high temperature by protecting optics using a gas protective layer and correcting for shotto-shot variance and lens-to-sample distance using a laser-induced acoustic signal. This study investigates cerium as a surrogate for uranium and corrosion products for simulating corrosive environments in LiCl-KCl. While the un-corrected limit of detection (LOD) range is 425-513 ppm, the acoustic-corrected LOD range is 360-397 ppm. The typical cerium concentrations in pyroprocessing are about two orders of magnitude higher than the LOD found in this study. A LIBS monitoring system that adopts these methods could have a significant impact on the ability to monitor and provide early detection of the transient behavior of salt composition in advanced molten salt-based nuclear reactors.

Rich Se Nanoparticles Modified Mo-W18O49 as Enhanced Electrocatalyst for Hydrogen Evolution Reaction

  • Wang, Jun Hui;Tang, Jia-Yao;Fan, Jia-Yi;Meng, Ze-Da;Zhu, Lei;Oh, Won-Chun
    • Korean Journal of Materials Research
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    • v.32 no.2
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    • pp.57-65
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    • 2022
  • Herein a rich, Se-nanoparticle modified Mo-W18O49 nanocomposite as efficient hydrogen evolution reaction catalyst is reported via hydrothermal synthesized process. In this work, Na2SeSO3 solution and selenium powder are used as Se precursor material. The structure and composition of the nanocomposites are characterized by X-ray diffraction (XRD), high-resolution field emission scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), EDX spectrum analysis and the corresponding element mapping. The improved electrochemical properties are studied by current density, and EIS analysis. The as-prepared Se modified Mo-W18O49 synthesized via Na2SeSO3 is investigated by FE-SEM analysis and found to exhibit spherical particles combined with nanosheets. This special morphology effectively improves the charge separation and transfer efficiency, resulting in enhanced photoelectric behavior compared with that of pure Mo-W18O49. The nanomaterial obtained via Na2SeSO3 solution demonstrates a high HER activity and low overpotential of -0.34 V, allowing it to deliver a current density of 10 mA cm-2.

A Study on the Jewelry decorative pattern based on Wa-Dang in Unified Silla period (통일신라시대 와당을 모티브로 한 주얼리장식용 문양 연구)

  • kyeng-Tae Kim
    • The Journal of the Convergence on Culture Technology
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    • v.9 no.6
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    • pp.113-122
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    • 2023
  • This study was conducted on the premise of the development of cultural products using relic assets of traditional culture in a knowledge and information society led by culture and soft power. It was conducted in the context of exploring the possibility of cultural content products of Wa-Dang relics excavated from traditional architecture in the Unified Silla Period and expanding the scalability of commercialization motifs that are highly useful in jewelry design. First, the original form, material, use, size, meaning, and formative aesthetics of Wa-Dang were identified through literature and media research. Among the considered Wa-Dang, 10 types of Wa-Dang which represent the category and have values in modules and patterns were selected, and, then, circular images were extracted and modularized with a "formal simplification technique." Based on the "mathematical symmetry analysis technique," which is a method of systematizing pattern composition arrangement format. we derived a planar formative element that can be used in the development of the cultural content industry and jewelry design. In order to expand its usability in the jewelry industry in the future, it was presented as a 2D digital image. In the future, we hope more studies on the various cultural content industry utilizing the traditional culture will be carried out.

Morphological and Structural Characterization of ZnO Films Deposited by Multiple Sol-Gel Methods (다중 졸-겔 방법에 의해 증착된 ZnO 막의 형태적 및 구조적 특성평가)

  • Muhammad Saqib;Woo Young Kim
    • Journal of the Korean Applied Science and Technology
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    • v.40 no.5
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    • pp.1116-1125
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    • 2023
  • Zinc oxide film is a transparent conductive material and is used in optoelectronic devices in various fields. Therefore, characterization of the zinc oxide film will play a very important role in improving the performance of optoelectronic devices. Here, we will evaluate the morphological and structural characteristics of such a zinc oxide film based on the solution process. Specifically, the sol-gel method will be repeatedly performed to observe the change in material properties of the zinc oxide film according to the number of times of spin-coating. It was confirmed that crystallization proceeded as a result of performing the sol-gel method repetitively 5 times under constant solution conditions. At 7 times or more, the element composition and crystallinity tended to converge to a specific value. The average crystal size of the final zinc oxide film was calculated to be about 10.7 nm. In this study, the number of processes showing optimal crystallization was 7 times. The results and methodology of this study can be applied while varying various solution process variables and are expected to contribute to establishing optimal process conditions.