• Title/Summary/Keyword: S/W Education

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Synthesis and Structural Properties of $VO_2$ Thin Films

  • Jin, Zhenlan;Park, Changin;Hwang, Inhui;Han, S.W.
    • Proceedings of the Korean Vacuum Society Conference
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    • 2013.08a
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    • pp.190.2-190.2
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    • 2013
  • Vanadium dioxide ($VO_2$) has been widely attracted for academic research and industrial applications due to its metal-insulator transition (MIT) temperature close to room temperature. We synthesized VOx film on (0001) sapphire substrate with vanadium target (purity: 99.9%) using DC magnetron sputtering in Ar ambience at a pressure of $10^{-3}$ Torr at $400{\sim}700^{\circ}C$. The VOx film subsequently was annealed at difference temperatures in ambience of Ar and $O_2$ gas mixture at $60{\sim}800^{\circ}C$. The structural properties of the films were investigated using scanning electron microscopic (SEM), x-ray diffraction (XRD) and x-ray absorption fine structure (XAFS) measurements. SEM reveal that small grains formed on the substrates with a roughness surface. XRD shows oriented $VO_2$(020) crystals was deposited on the $Al_2O_3$(006) substrate. From I-V measurements, the electric resistance near its MIT temperature were dramatically changed by ${\sim}10^4$ during heating and cooling the films. We will also discuss the temperature-dependent local structural changes around vanadium atoms using XAFS measurements.

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Synthesis and Temperature-Dependent Local Structural Properties of Ti2O3

  • Hwang, Inhui;Jin, Zhenlan;Park, Changin;Jiang, Bingzhi;Han, S.W.
    • Proceedings of the Korean Vacuum Society Conference
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    • 2013.08a
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    • pp.202.2-202.2
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    • 2013
  • Ti2O3 is known as a typical Mott insulator with a transition temperature of near $200^{\circ}C$. Unlike VO2, Ti2O3 does not have a structural phase transition near the metal-insulator-transition (MIT) temperature. We investigated the temperature-dependent thermal vibration change using temperature-dependent x-ray absorption fine structure (XAFS) at Ti K-edge in the temperature range of 300~600 K. Ti2O3 powder and films were synthesized using thermal chemical vapor deposition (CVD) at $800{\sim}900^{\circ}C$. X-ray diffraction measurements show a single phased Ti2O3 at room temperature. XAFS confirmed no structural phase transition in the temperature of 300~600 K. A small but distinguishable structural disorder change was observed near the transition temperature. We will discuss the MIT behavior with the change of structural disorder.

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Augmented Reality (AR)-Based Smartphone Application as Student Learning Media for Javanese Wedding Make Up in Central Java

  • Ihsani, A.N.N.;Sukardi, Sukardi;Soenarto, Soenarto;Krisnawati, M.;Agustin, E.W.;Pribadi, F.S.
    • Journal of information and communication convergence engineering
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    • v.19 no.4
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    • pp.248-256
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    • 2021
  • The purpose of this study was to introduce an application as a learning medium that can be used by students to prepare Solo bridal paes. This application can be used by make-up beginners who are learning about Solo bridal paes. This study used a quasi-experimental method with a randomized pretest-posttest control group. The paes application can be used as a medium in Solo bridal makeup learning, because it is highly effective in helping students prepare Solo bridal paes. This application is also considerably practical because it can be installed on smartphones. Experimental results revealed a difference between the control and experimental classes. Students in the experimental class could prepare paes neatly, and their shapes were proportional to the face of the model. The use of augmented reality as a medium to teach Solo bridal makeup, especially for making paes, is an innovation in the world of education. This application can help students make paes.

A Study on Searching Algorithm for Malfunction Pattern of Protection Devices in Distribution System with PV Systems (태양광전원이 연계된 배전계통 보호협조기기의 부동작패턴 탐색알고리즘에 관한 연구)

  • Kwon, Soon-Hwan;Tae, Dong-Hyun;Lee, Hu-Dong;Rho, Dae-Seok
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.21 no.9
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    • pp.652-661
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    • 2020
  • Recently, the Korean government developed the RE3020 (renewable energy) policy to overcome environmental problems, such as fine dust, climate change, and large-scale PV systems interconnected with a distribution system. When a large-scale PV system is interconnected in the distribution system, however, a malfunction can occur, and the protection devices may not be operated because of the dividing effect depending on the magnitude and direction of fault current as well as connection types and location of the PV system. Therefore, this paper proposes a search algorithm for the malfunction pattern of protection devices based on various scenarios, when large-scale PV systems are operated and interconnected in a distribution system. This paper presents a malfunction mechanism of protection devices according to the installation locations of recloser (R/C). Furthermore, the modeling of a distribution system with large-scale PV systems was performed using Off-DAS S/W, and the malfunction patterns of protection devices were analyzed based on a range of scenarios. From the simulation results with the proposed model and algorithm for searching for protection devices, it was confirmed that they are useful and effective in identifying a malfunction phenomenon depending on the installation location of the R/C and connection type of PV system.

Propensity Analysis for Oral Exam Candidates of Sixth Class Engineer Officer's License using Questionnaire (설문에 의한 6급 기관사 면허 면접시험 응시자의 성향 분석)

  • Park, Tae-Geon;Lee, Yoo-Won;Kim, Yong-Bok
    • Journal of Fisheries and Marine Sciences Education
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    • v.26 no.5
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    • pp.1151-1157
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    • 2014
  • The propensity analysis for oral exam candidates of sixth class engineer officer's license was conducted to serve as a basic data for improving the ability of seamanship and a stable workforce supply using a questionnaire. A general information of them was identified as 62.1% of offshore fishing, 59.3% of over 50, 59.4% of less middle school education, 52.4% of under 100 gross tonnage, 75.2% of under 1,500kW engine output, 72.5% of over 10 years experience, 72.4% of engine department, which means they are from mainly less than 100 gross tonnage of offshore fishing vessel, less educated, and long term experienced in the engine job. The reason why they took the test was mainly due to their will (51.7%). And 45.5% of them took the test for the first time, 45.5% of answers responded they are lack of knowledge about a written exam and text of KIMFT in preparation data for an oral exam 35.9%. Given the fact that 74.5% of respondents experienced marine accidents with engine damage on board, the need for marine casualty reduction education was verified. Even after obtaining a license, they showed a higher preference of boarding that they embarked before the examination. Also, 61.4% of them have a plan for long-term boarding at least three years, thus leading to supply of workforce in coastal and offshore areas.

A Study on Operation Method of Protection Device for LVDC Distribution Feeder in Light Rail System (경전철용 LVDC 배전계통의 보호기기 운용 방안에 관한 연구)

  • Kang, Min-Kwan;Choi, Sung Sik;Lee, Hu-Dong;Kim, Gi-Yung;Rho, Dae-Seok
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.20 no.4
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    • pp.25-34
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    • 2019
  • Recently, when a fault occurs at a long-distance point in a LVDC (low voltage direct current) distribution feeder in a light rail system, the magnitude of the current can decrease to less than that of the load current of a light rail system. Therefore, proper protection coordination method to distinguish a fault current from a load current is required. To overcome these problems, this paper proposes an optimal algorithm of protection devices for a LVDC distribution feeder in a light rail system. In other words, based on the characteristics of the fault current for ground resistance and fault location, this paper proposes an optimal operation algorithm of a selective relay to properly identify the fault current compared to the load current in a light rail system. In addition, this paper modelled the distribution system including AC/DC converter using a PSCAD/EMTDC S/W and from the simulation results for a real light rail system, the proposed algorithm was found to be a useful and practical tool to correctly identify the fault current and load current.

Genetic Diversity and Population Structure in Native Chicken Populations from Myanmar, Thailand and Laos by Using 102 Indels Markers

  • Maw, A.A.;Kawabe, Kotaro;Shimogiri, T.;Rerkamnuaychoke, W.;Kawamoto, Y.;Masuda, S.;Okamoto, S.
    • Asian-Australasian Journal of Animal Sciences
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    • v.28 no.1
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    • pp.14-19
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    • 2015
  • The genetic diversity of native chicken populations from Myanmar, Thailand, and Laos was examined by using 102 insertion and/or deletion (indels) markers. Most of the indels loci were polymorphic (71% to 96%), and the genetic variability was similar in all populations. The average observed heterozygosities ($H_O$) and expected heterozygosities ($H_E$) ranged from 0.205 to 0.263 and 0.239 to 0.381, respectively. The coefficients of genetic differentiation (Gst) for all cumulated populations was 0.125, and the Thai native chickens showed higher Gst (0.088) than Myanmar (0.041) and Laotian (0.024) populations. The pairwise Fst distances ranged from 0.144 to 0.308 among populations. A neighbor-joining (NJ) tree, using Nei's genetic distance, revealed that Thai and Laotian native chicken populations were genetically close, while Myanmar native chickens were distant from the others. The native chickens from these three countries were thought to be descended from three different origins (K = 3) from STRUCTURE analysis. Genetic admixture was observed in Thai and Laotian native chickens, while admixture was absent in Myanmar native chickens.

A Study on the Basic Education Program of Fashion Drawing (패션 드로잉을 위한 기초교육에 관한 연구)

  • Chang, Dong-Rim
    • Journal of Fashion Business
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    • v.1 no.1
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    • pp.84-98
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    • 1997
  • This study is to develop a fashion drawing education program which is based on the theory of 'Split-brain' by Roger W. Sperry and 'Drawing on the Right Side of the Brain' by Betty Edwards. Students in Fashion Design start their training by developing a foundation in drawing and studing the tools, materials and methods of the Industry. Ideas are then developed on paper, later translated into three-dimensional shapes and finally into finished garments. Fashion drawing and design techniques train the hand and eye to all the nuances of fashion design and illustration. Fashion drawing course deals with the sketching of fashion models for the purpose of understanding the model figure, basic anatomy, movement and figure attitudes. Having mastered the basic skills, students take advanced drawing course which is developing awareness of design, needs, of fashion market' using various media for the purpose of developing a designer's sketch, with emphasis on the drawing and designs. Featured aspects of this study include the following; 1. Drawing the negative space; basic visual concepts 2. Contour drawing; constructs, visual measurement, movement 3. Model drawing; the classical method, proportion, symmetry. The primary aim of this study is to develop a sensitive, animated line based on observed form. It is important to let the students Imagine that they are actually touching the model, for in this way they can benefit from simulating the child's learning process. Instead of actually touching the model they are using their eyes as an extension of their sense of touch.

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Theoretical and Experimental 31P NMR and ESI-MS Study of Hg2+ Binding to Fenitrothion

  • Koo, In-Sun;Ali, Dildar;Yang, Ki-Yull;vanLoon, Gary W.;Buncel, Erwin
    • Bulletin of the Korean Chemical Society
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    • v.30 no.6
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    • pp.1257-1261
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    • 2009
  • We present the theoretical and experimental results of $^{31}P$ NMR and low energy CID MS/MS study of $Hg^{2+}$ binding to fenitrothion (FN). The calculated $^{31}P$ NMR chemical shifts order for FN with $Hg^{2+}$ complex is in good agreement with experimental $^{31}P$ NMR chemical shifts order. The experimental and theoretical $^{31}P$ NMR study of organophosphorus pesticide with $Hg^{2+}$ gives to important information for organophosphorus pesticide metal complexes. ESI-MS and low energy CID MS/MS experiments of $Hg^{2+}$-FN complexes combined with accurate mass measurements give insight into the metal localization and allow unambiguous identification of fragments and hydrolysis products.

The Effect of a Group Program Using Theraplay on Prosocial Behavior of 2-year-old Infants and Process of Infants' Prosocial Behavior Change (치료놀이를 활용한 집단프로그램이 만 2세 영아의 친사회적 행동에 미치는 영향과 영아의 친사회적 행동 변화 과정)

  • Kim, Tae Eun;Jeon, A Jeong
    • Korean Journal of Child Education & Care
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    • v.19 no.3
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    • pp.183-197
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    • 2019
  • Objective: The purpose of this study was to examine the effect of a group program using theraplay on 2-year-olds' prosocial behavior. The changes of prosocial behavior in the process of program were also examined. Methods: Subjects were 12 infants who attended a child care center in W city. Subjects were attached to the experimental or control group. The experimental group participated in 11 group theraplay sessions twice a week. The adaptive social behavior inventory (Hogan et al., 1992) was used for pre and post tests. Wilcoxon rank-sum test was performed to verify the effectiveness of a group theraplay program. Every sessions was video-taped and recorded verbatim. The verbatim were analyzed using the Padgett (2001)'s qualitative data analysis method. Results: Infants who assigned to the experimental group demonstrated significant improvement in prosocial behavior. Their expressive behavior and compliant behavior gradually increased over the sessions. Conclusion/Implications: The present study showed that the use of group program utilizing theraplay was an effective strategy for improving prosocial behavior of 2-year-old infants.