• Title/Summary/Keyword: 접촉효과

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A Study on Relationship between Contact with North Korea and North Korean Settlers and Perceptions of Unification : Multiple Mediator Effect of Intimacy with North Korean Settlers and Perception of North Korea (북한 및 탈북민 접촉경험이 통일의식에 미치는 영향 : 탈북민 친밀감과 북한에 대한 인식의 매개효과를 중심으로)

  • Kim, Na-Young
    • The Journal of the Korea Contents Association
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    • v.21 no.8
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    • pp.489-497
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    • 2021
  • This study presents the results of an empirical analysis on whether the experience of contact with North Korea and North Korean settlers affects the perceptions of unification. Specifically, the purpose of this study was to examine whether the contact experience enhances intimacy with the North Korean settlers or raises a friendly perception of North Korea.The results of this study are as follows. First, the experience of contact with North Korea and North Korean defectors had a positive effect on intimacy with North Korean settlers, friendly perception of North Korea, and perceptions of unification. Second, intimacy toward North Korean settlers and perception of North Korea played a mediating role between contact experience and unification consciousness.

Analysis of Contact Problem of Mating Gear Teeth Taking Account of Friction on the Involute Surface (마찰을 고려한 치차의 접촉 문제 해석)

  • 이대희;최동훈
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.13 no.6
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    • pp.1118-1127
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    • 1989
  • 본 연구에서는 두 치차사이의 접촉 문제를 해석하기 위하여 마찰을 고려한 수직 하중과 접선 하중이 동시에 작용하는 경우에서의 접촉 문제를 수식화하였다. 그리고 두개의 원통의 접촉으로 가정함이 없이 실제적인 인벌루우트 곡면간의 접촉 문제를 해석하기 위하여 유한 요소법을 사용하였으며 비선형 연립 방정식으로 수식화된 된 접촉 문제를 효과적으로 풀기 위하여 최적화 기법을 이용한 산법을 제시하였다. 이때 마찰을 고려한 치차의 접촉 문제 해석에 필요한 수직 압력 분포는 이 등에 의하여 이루어진 결과를 이용하였다. 제시한 산법에 의하여 마찰을 고려한 두 치차의 접촉 문제를 해석하여 치차 손상의 중요한 원인중의 하나인 피팅(pitting) 현상을 유발하는 실제적인 조건을 고려함으로써 자동화 및 정밀화 되어가는 기계의 중요한 부품으로서 치차의 정밀 설계를 하기 위한 정확한 자료를 제시하였다.

Water Quality Improvement Using Inverted Siphon Curved Channel System of Serial Contact Materials (연속접촉재 역사이폰 만곡수로 시스템의 수질개선)

  • Lee, Jong-Seok;Lee, Seung-Young
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.31 no.6B
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    • pp.541-550
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    • 2011
  • This study sets the goal to improve effectively water quality of stream by complementing the weak points of the gravel contact oxidation process to use the inverted siphon curved channel system in free overfall of serial contact materials. The size of the current system can be diminished by expanding contact time, and the materials' replacement can be made easier when their gap are closed through the filtering boxes of contact materials. This system also has been developed into a construction method in which mixed and serial contact materials can be employed by using just the conventional single contact materials. It was verified the improvement ability of water quality of this system, during the simulation test at Tandong stream in Daejeon. The results of the verification of water quality improvement through several experiments in field were measured as follows : it showed to reduce about the averaged 55~83% higher than 60~75%, the internal planned goal of water quality improvement facilities.

Relationship between College Students' Multicultural Contact Experiences and Multicultural Competency: Mediating Effects of Perspective Taking and Prejudice (대학생의 다문화 접촉경험과 다문화 역량의 관계: 조망수용과 편견의 매개효과)

  • Gahee Choi
    • Korean Journal of Culture and Social Issue
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    • v.29 no.3
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    • pp.341-359
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    • 2023
  • This study investigated effects of college students' multicultural contacts on multicultural competency. This study also examined mediating effects of perspective taking and prejudice. Multicultural contacts were divided into quality of contacts and quantity of contacts. Effects of quality and quantity of contacts on multicultural competency through perspective taking and prejudice were separately analyzed using two models. For the purpose, 642 Korean college students completed the questionnaires including multicultural contacts, multicultural competency, perspective taking, prejudice and demographic information. The results indicate that both quality and quantity of contacts are associated with multicultural competency, but quality of contacts are more strongly associated with multicultural competency. Also, perspective taking and prejudice mediate the relationship between quality of contacts and multicultural competency while mediators did not mediate the relationship between quantity of contacts and multicultural competency. The results indicate that intimate and positive contacts with outgroup members help enhance college students' multicultural competency through increased perspective taking and prejudice reduction. Future multicultural education for undergraduate students should focus on increasing the quality of multicultural contacts and help them with perspective taking, and reducing prejudice.

Effects of Low Pressure and Atmospheric Pressure Plasma Treatment on Contact Angle of Polycarbonate Surface (저압 및 대기압 플라즈마 처리를 통한 폴리카보네이트의 접촉각 변화특성 비교)

  • Won, Dong Su;Kim, Tae Kyung;Lee, Won Gyu
    • Applied Chemistry for Engineering
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    • v.21 no.1
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    • pp.98-103
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    • 2010
  • The effect of plasma treatment on surface characteristics of polycarbonate (PC) films was investigated using low pressure plasma and atmospheric pressure plasma with oxygen and argon. Untreated PC has a contact angle of $82.31^{\circ}$ with de-ionized water which reduced to $9.17^{\circ}$ as the lowest value after being treated with a low pressure plasma treatment with oxygen. Increase of delivered powers such as RF and AC with a high frequency and gas flow rates was not effective to reduce contact angles dramatically but gave the trend of reducing gradually. The surface of PC treated with plasma shows a low contact angle but the contact angle increases rapidly according to the exposure time in air ambient. Oxygen plasma was more effective to generate the polar functional group regardless of the type of plasma. Conclusively, a low plasma treatment with oxygen is more recommendable when the hydrophilic surface of PC is required.

Effect of Theaflavin and Thearubigin from Microbial Fermented Teas on Urushiol Allergic Contact Dermatitis (미생물 발효차의 Theaflavin.Thearubigin에 의한 옻 알레르기성 접촉피부염에 미치는 영향)

  • Shon, Mi-Yae;Nam, Sang-Hae;Park, Seok-Kyu
    • Food Industry And Nutrition
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    • v.11 no.3
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    • pp.44-48
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    • 2006
  • 본 연구는 옻(Rhus verniciflua)에 대한 국산 미생물 발효차 폴리 페놀물질 인 theaflavin(TF)과 thearubigin(TR)의 항알레르기 효과를 조사하였다. HPLC, column chromatography 및 TLC로 이용하여, 한국 원주산, 일본산 및 중국산 락커(lacquer)로부터 아주 강한 알레르기를 유발하는 long chain alkylphenol을 함유하는 crude urushiol 성분을 분리하였다. 고분자 이중 및 삼중불포화물질의 함량은 중국산 라커의 crude urushiol에 가장 많이 포함되어 있었다. 중국산 라커의 crude urushiol에서 유발되는 접촉성 알레르기 피부염 발생은 5%농도에서 한국산이나 일본산 라커의 시료보다 높았으며, TF 및 TR를 처리한 모든 농도에서 접촉성 알레르기 피부염의 유의적인 감소를 나타내었다. 이들 결과로부터 발효차의 폴리페놀성 TF와 TR은 옻의 접촉성 피부염에 대한 유의적인 항알레르기 효과를 나타내었다.

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Modeling on the facilitated mass transfer in membrane contactor and its design basis (막접촉기에서의 촉진물질전달에 관한 모델링과 설계 기초)

  • 장재동;전명석;정귀영;김재진
    • Proceedings of the Membrane Society of Korea Conference
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    • 1998.10a
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    • pp.39-42
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    • 1998
  • 1. 서론 : 막을 경계로 접촉한 두 상(phase)간의 물질전달에 의해 물질을 효과적으로 분리해내는 막접촉기(membrane contactor) 방식은 추출이나 흡수에 적용되고 있다. 이것은 고전적인 충전탑이 갖는 접촉면적의 한계, 불안정한 유체유동의 단점을 가급적 극복할 수 있다는 측면에 있다. 막접촉방식의 하나인 막 흡수법의 경우, 흡수제(absorbent)를 정지시킨 contained(혹은, supported) liquid membrane 방식에서 인공폐의 원리를 기초로 독립적으로 분리시킨 흡수와 탈착모듈간의 계속 순환시키는 circulatory membrane absorber방식이 제안되었다.(생략)

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Effects of Korean College Students' Contacts with International Students on Multicultural Competencies: Mediating Effects of Life Satisfaction and Realistic Conflict Perception (한국인 대학생의 외국인 유학생과의 접촉이 다문화 역량에 미치는 영향: 삶의 만족도와 현실갈등인식의 매개효과)

  • Gahee Choi
    • Korean Journal of Culture and Social Issue
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    • v.25 no.4
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    • pp.279-303
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    • 2019
  • This study investigated effects of Korean students' contacts with International students on Korean college students' multicultural competencies. This study also examined mediating effects of life satisfaction and realistic conflict perception between contacts with international students and multicultural competencies. For the purpose, 384 Korean college students completed the questionnaires including contacts, life satisfaction, realistic conflicts perception toward international students, everyday multicultural competencies, and demographic information. The results indicate that number of contacts predicts cultural self-efficacy and cultural knowledge, whereas contact diversity predicts cultural openness. Life Satisfaction predicts cultural openness, cultural self-efficacy, and cultural knowledge, and realistic conflicts perception predicts all subscales of everyday multicultural competencies scale other than cultural knowledge. Results also discovered that life satisfaction mediates the relationship between contact diversity and multicultural competencies, but realistic conflict perception did not mediate between contact diversity and multicultural competencies. Based on the results, the suggestions to enhance college students' multicultural competencies were discussed.

LFC 태양전지에서 접촉 면적 가변을 통한 전지 효율 변화 분석

  • Lee, Won-Baek;Lee, Yong-U;Jeong, Seong-Uk;Jang, Gyeong-Su;Park, Hyeong-Sik;Lee, Jun-Sin
    • Proceedings of the Korean Vacuum Society Conference
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    • 2010.02a
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    • pp.300-300
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    • 2010
  • 후면 패시베이션, back contact의 가변, 후면 접촉면적의 가변 등으로 Laser Fired Contact 태양전지의 효율을 증가 시킬 수 있다. 이 중 spacing의 가변으로 후면 접촉 면적을 가변 할 수 있으며, 이로 인하여 LFC 태양 전지의 효율을 높일 수 있을 것으로 전망된다. 본 연구에서는 후면 접촉 면적을 가변하였으며 이에 따른 효과를 확인하였다. series resistance가 작고, open circuit voltage 가 높은 최적의 조건을 찾는 것에 그 목적을 두었다. 실험 순서는 texturing 후, 후면에 SiNx를 10nm 증착하였으며, drive-in 방법으로 $POCl_3$을 도핑하였다. ARC후, spacing 조건 가변으로 접촉 면적을 가변시키면서 소자의 특성 변화를 비교하였다. 접촉 면적 및 spacing 조건은 5개의 set에 대하여 reference, 50%의 접촉 면적을 가지는 $150{\mu}m$ line, 10%의 접촉 면적을 가지는 $700{\mu}m$ line, 1%의 접촉 면적을 가지는 $700{\mu}m$ dot, 그리고 0.2%의 접촉 면적을 가지는 $1500{\mu}m$ dot으로 하였다. 각각의 경우에 대한 short circuit current density, fill factor, seris resistance, sheet resistance, open circuit voltage를 측정하였으며, 특히 series resistance는 각각의 경우에 대하여 $6.1m{\Omega}$, $5.1m{\Omega}$, $7.8m{\Omega}$, $10.1m{\Omega}$, 그리고 $15.7m{\Omega}$으로 측정되었다. wafer의 외각 테두리를 접촉 면적이 증가함에 따라서 sheet resistance가 증가하는 것을 확인 할 수 있었다.

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