• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2002년도 춘계학술대회 논문집
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• pp.816-819
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• 2002

This paper is the study on stress analysis for tooth modification of high speed gear using a finite element method. Gear drives constitute very important mechanisms in transmitting mechanical power processes compromising several cost effective and engineering advantages. The load transmission occurred by the contacting surfaces arises variable elastic deformations which are being evaluated through finite element analysis. The automatic gear design program is developed to model gear shape precisely. This gear design system developed was used by pre-processor of FEM packages. The distribution of stresses at contacting surfaces was examined when gear tooth contacts. And this paper proposes method for the tooth modification after carrying out stress analysis using a finite element method.

• 한국강구조학회 논문집
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• 제8권3호통권28호
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• pp.117-125
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• 1996

The stress patterns of vertical stiffener of plate girder bridge were examined by existing data of actual measurement stress for steel bridges and the structural details of vertical stiffener of plate girder bridge having seeked rationalization and abbreviation were investigated by 1/2 bridge model. As the results, the out-of-plane stress occur in the upper parts of vertical stiffner and fatigue cracks by the action of alternative stress is apt to occur in web plate of lower parts vertical stiffener. Also, the gap between lower parts of vertical stiffner and lower flange of plate girder bridge seeking rationalization and abbreviation is effective to adopt 100mm.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1996년도 봄 학술발표회 논문집
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• pp.270-274
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• 1996

Until recently pre & post-processing of finite element model has been heavily relied on expensive graphic peripheral devices. But today, with the aid of inexpensive microcomputers, very effective pre & postprocessor graphics has been developed. In this study, Pre & Post processor(MASSPRE, MASSPOST) of prediction analysis of thermal stress in mass concrete structure is developed. The developed pre & post processors are raise to the efficiency in making input data for the main program and analysis of the results produced by the main program. This MASSPOST presents a stress contour graph, volume slice, time-temperature history graph, time-stress history graph, etc.

• 한국지역사회생활과학회지
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• 제14권1호
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• pp.1-12
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• 2003

The purpose of this study was to investigate the maternal parenting stress and related variables through early childhood in rural areas (Iksan and Kimpo). The subject were 134 mothers who have less than 5-year old children. The statistics used for this data were freguency, percentile, t-test, ANOVA, and multiple regression analysis. The main results obtained from this study were as follows. The degree of maternal parenting stress differed according to level of mother's education, sex of the child, physical and mental health of the mother, child rearing attitudes, mother's level of self-differentiation, marital satisfaction, and father's parenting support. Results of the regression analysis that the etiologic model of this study were that father's parenting support is the most effective variables in rural areas.

• 한국정밀공학회지
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• 제20권2호
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• pp.162-167
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• 2003

This paper is the study on stress analysis for tooth modification of high speed gear using a finite element method. Gear drives constitute very important mechanisms in transmitting mechanical power processes which compromise several cost effective and engineering advantages. The load transmission which occurred by the contacting surfaces arises variable elastic deformations evaluated through finite element analysis. The automatic gear design program was developed to model gear shape precisely. This developed gear design system was used by pre-processor of FEM packages. The distribution of stresses at contacting surfaces was examined when gear tooth contacts. And this paper proposes a method for the tooth modification after carrying out stress analysis using a finite element method.

• 디지털융복합연구
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• 제15권2호
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• pp.251-262
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• 2017

본 연구는 Bronfenbrenner의 생태학적 체계이론을 바탕으로 대학생의 정신건강에 영향을 미치는 요인을 구분하고 통합적인 모형 구축과 정신건강 증진을 위한 간호중재 개발의 기틀을 마련하고자 한다. 연구방법은 횡단적 조사연구로 대학생을 대상으로 하였다. 일반적 특성 및 정신건강관련 특성은 SPSS 20.0 프로그램을, 모형의 적합도검증, 가설검증은 Amos 20.0 프로그램을 이용하였다. 연구결과에서 모형의 적합도 지수는 $x^2=614.90$(p=.000), Q값=3.5, GFI=.88, AGFI=.84, NFI=.92, NNFI=.94, CFI=.94, RMR=.02, RMSEA=.08 적합도를 나타내어 연구모형이 가정에 적합한 것으로 나타났다. 연구결과 정신건강에 스트레스가 가장 높은 영향을 미치고 있으며 스트레스 대처 방안과 자아 존중감, 부모의 양육태도가 정신건강에 영향을 미치는 것으로 확인되었다. 대학생의 정신건강을 증진시키기 위해서는 스트레스 관리, 자아존중감 증진, 스트레스 대처 능력 향상을 도모하는 간호중재를 개발하고, 학교현장 및 정신보건 실무에 활용하는 중재가 수행되어야 할 것으로 생각된다.

• 전자공학회논문지A
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• 제32A권6호
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• pp.59-66
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• 1995

The hot electron induced effective channel length modulation (${\Delta}L_{H}$) and HEIP characteristics in PMOSFET's after bidirectional stress are presented. Trapped electron charges in gate oxide and lateral field are calculated from the gate current model, and ${\Delta}L_{H}$(${\Delta}L_{HD},\;{\Delta}L_{HS}$) is calculated using trapped electron charges and lateral field. It has been found that ${\Delta}I_{d}$and ${\Delta}L_{H}$ are more affected by the stress order (Forward-Reverse of Reverse or Reverse-Forward) than the stress direction, and they vary logarithmically with the stress time. In contrast, ${\Delta}V_{t}$ and ${\Delta}V_{pt}$ are more affected by the stress direction thatn the stress order. The correlation between ${\Delta}V_{pt}$ and the stress time can be explanined as the following polynomial functin: ${\Delta}V_{pt}$=AT$^{n}$. It has also been shown that PMOSFET degradation is related with the gate current and the effects of ${\Delta}V_{pt}$ is the most significant.

• Human Ecology Research
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• 제60권3호
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• pp.345-358
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• 2022

This study examined the moderated mediating impact of entrapment and emotional support from peers in the relationship between academic stress and suicidal ideation among middle-school students. The participants consisted of 214 middle-school students in the first to third grades from four middle schools located in Seoul, Gyeong-gi, Chun-cheon, and Jeonnam. The data were analyzed using descriptive statistics, Pearson's correlation coefficients, and the Process Macro Model versions 4, 1, and 14. The results of this study were as follows. First, academic stress did not directly influence suicidal ideation; however, entrapment mediated the relationship between academic stress and suicidal ideation. Second, emotional support from peers moderated the mediating effect of entrapment in the aforementioned relationship. This means that if students perceived emotional support from peers, then academic stress had a smaller impact on suicidal ideation through entrapment. These findings highlight the importance of decreasing levels of academic stress and entrapment to prevent suicidal ideation among middle-school students. They also suggest that enhancing students' emotional support networks with their peers could be an effective way of reducing suicidal ideation when students feel high levels of entrapment and academic stress.

• 전자공학회논문지A
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• 제31A권8호
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• pp.72-79
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• 1994

In this paper semi empirical models are presented for the hot electron induced threshold voltage shift(${\Delta}V_{t}$) and effective channel shortening length (${\Delta}L_{H}$) in degraded PMOSFET. Trapped electron charges in gate oxide are calculated from the well known gate current model and ΔLS1HT is calculated by using trapped electron charges. (${\Delta}L_{H}$) is a function of gate stress voltage such as threshold voltage shift and degradation of drain current. From the correlation between (${\Delta}L_{H}$) has a logarithmic function of stress time. From the measured results, (${\Delta}V_{t}$) and (${\Delta}L_{H}$) are function of initial gate current and device channel length.

• 한국지반공학회논문집
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• 제24권3호
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• pp.35-51
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• 2008

본 논문에서는 액상화 해석에 관한 DSC 모델을 실험 및 해석적 관점에서 그 적용성을 평가하였다. 포화 사질토의 동적거동을 보다 정확히 예측하기 위해 DSC 모델을 유효응력 경로와 과잉간극수압 발현에 기초하여 수정하였다. 액상화에 대한 동적거동 및 DSC 모델에 대한 매개변수 산정을 위해 정적배수삼축시험과 반복 비배수삼축시험을 상대밀도와 구속응력에 따라 수행하였다. 유효응력 경로와 과잉간극수압의 항으로 액상화 상태를 분류하고 수정된 DSC 모델을 적용시켜 액상화 해석을 수행하였다. 제안된 방법을 토대로 DSC 모델과 제안된 DSC 모델에 대한 액상화 해석을 상대밀도와 구속응력에 따라 비교하였다. 비교 결과 수정 모델은 액상화 시작점 및 동적 거동을 보다 정밀하게 평가하였고, 입력변수의 수가 감소하고 산정방법이 간편해졌다.