• 예술인문사회 융합 멀티미디어 논문지
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• 제7권2호
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• pp.427-435
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• 2017

환경문제로 국내 시내버스의 대부분은 압축천연가스(CNG)를 연료로 사용하며, 연료 저장용기는 내압을 받는 압력용기를 사용하고 있다. 내압을 받는 압력용기는 여러 가지의 형태와 목적을 지니고 있다. 연료가 가연성이고 고압으로 인한 폭발성을 지니고 있으므로 압력용기의 파손사고는 많은 재산피해와 인명피해를 일으킨다. 이에 대한 안전한 설계가 반드시 필요하므로 유한요소해석을 이용하여 많은 연구들이 진행되고 있다. 본 연구에서 유한요소 해석 소프트웨어인 ANSYS를 이용한 응력해석을 탄성이론의 구형 돔 형상 응력이론식과 실린더 형상 응력이론식을 비교하여 해석의 타당성을 입증 하기위해 돔의 형상이 완전 구형인 모델을 설계하여 관찰하였고 실제 사용중인 ASME 규격이론을 바탕으로 압축천연가스(CNG)로 설계된 모델에 대해서도 응력분포를 분석하였다. 유한요소 해석 소프트 웨어를 사용하여 돔 형상이 완전이 구형인 모델을 해석 하였을 때 이론과 잘 일치 하였고 ASME 규격이론을 바탕으로 설계한 모델에서는 너클부분에 응력집중 현상이 발생하였다.

• 보건교육건강증진학회지
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• 제26권1호
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• pp.1-13
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• 2009

Objectives: This study was conducted to estimate the health-related quality of life (HRQOL) using EuroQoL-5 Dimension (EQ-5D) and to identify its related factors among urban-dwelling adults. Methods: The data for this study were obtained from 1,134 subjects aged $20\sim91$, who participated in 'Survey on the health status and demand for health' in two cities of Korea (Dong-gu, Gwangju and Suncheon-si, Jeollanamdo). The HRQOL was measured using the EQ-5D instrument and EQ-5D index scores were calculated by two Korean valuation study model using time trade-off method. Results: The mean EQ-5D index scores for all subjects were $0.865{\pm}0.218$ (model A), and $0.921{\pm}0.170$ (model B). The EQ-5D index score was significantly different according to demographic and socioeconomic characteristics (gender, age, marital status, education, occupation, income, and health security system), self-rated health condition, health-related psychological assessments (enough sleep, fatigue rate, stress rate, and degree of satisfaction on the residence). The results of multiple linear regression showed that age, marital status, income, coverage of medical insurance, self-rated health condition, and fatigue rate were significantly related common statistical factors of HRQOL in two Korean valuation study model. Conclusion: Among the adults residing in urban environment, the HRQOL was significantly lower on the subjects with following conditions: higher age, being alone without a spouse as a result of death, divorce or separation, low income, medical aid program, poor self-rated health condition, and chronic fatigue. In order to improve the urban adults' quality of life, healthcare policy and health promotion program must be developed with considerations to factors related to the HRQOL.

• 보건교육건강증진학회지
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• 제31권3호
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• pp.15-26
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• 2014

Objective: This study was conducted in order to explore the predictive model of the experience of harmful shops in middle and high school students. Methods: The survey was conducted using a self-administered questionnaire method online via the homepage of the education ministry's student health information center. Participants were 1,888 middle school students and 1,563 high school students from 107 schools in Korea. The collected data were processed using the SPSS classification trees 18.0 program and examined using data mining decision tree model. Results: In this study, 6.9% of all subjects were found to have been to sex industry harmful place and 81.8% game place. The results revealed that smoking, living with parents, and school grade were significant predictors for experience of sex industry harmful place. The perception of study disrupts, drinking, living with parents, stress, and satisfaction of school life were significant predictors for experience of game harmful place. Conclusions: These results suggest that an educational approach should be developed by tailored conditions to prevent the access to harmful shops.

• 한국기계가공학회지
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• 제15권1호
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• pp.74-80
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• 2016

Due to the increased use of power caused by industrial development, the importance of improving wear and friction in the contact region has emerged. Except for some parts, such as brakes or clutches and friction, seals and precision mechanical parts (e.g., pistons, bearings, valves, and cams) are important engine components that require low friction characteristics. In this study, the experimental method used to determine the friction characteristics was based on the type of rpm with the pin-on-disc test device, the element analysis program ANSYS was used to analyze the surfaces of the two metals rubbing together, and physical formation FEM models were used to study the properties and wear. The friction coefficient of variation was unsafe, but at the start of wear, it converged to a stable friction coefficient that increased after a certain slip away.

• 가정과삶의질연구
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• 제33권1호
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• pp.1-17
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• 2015

This study investigated how variables of internalizing and externalizing problematic behaviors change according to gender and as time passes by and how the variables influence adolescent problematic behaviors. The variables selected for the analysis are personal variables, parent variables, peer and school variables, and community variables. longitudinal data collected for 4 years from the Korea Youth Panel Survey(KYPS) were utilized for the analysis. Data were collected initially from 2,707 fifth grade elementary students in 2005 and they were traced until 2008. The final respondents were 2,448 students. The findings are as follows. Frist, the statistical significance was found in changes of problematic behavioral variables in terms of the gender difference. Second, variables, such as self-esteem and self-control are negatively correlated to the problematic behaviors and stress level is strongly positively correlated to the behaviors. Third, the study pressure and peer attachment level are correlated to the initial value of internalizing problematic behaviors. In conclusion, given that more statistical significances were found at initial values than the change rates among variables, early intervention is important in addressing adolescent problematic behaviors.

• 한국해양공학회지
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• 제19권6호통권67호
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• pp.58-63
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• 2005

The estimation of springing responses for recent ships is carried out, and application to a ship design is described. To this aim, springing effects on hull girder were re-evaluated, including non-linear wave excitations and torsional vibrations of the hull. The Timoshenko beam model was used to calculate stress distribution on the hull girder, using the superposition method. The quadratic strip method was employed to calculate the hydrodynamic forces and moments on the hull. In order to remove the irregular frequencies, we adopted 'rigid lid' on the hull free surface level, and addedasymptotic interpolation along the high frequency range. Several applications were carried out on the following existing ships: The Bishop and Price's container ship, S-175 container ship, large container, VLCC, and ore carrier. One of them is compared with the ship measurement result, while another with that of the model test. The comparison between the analytical solution and the numerical solution for a homogeneous beam-type artificial ship shows good agreement. It is found that Most springing energy comesfrom high frequency waves for the ships having low natural frequency and North Atlantic route etc. Therefore, the high frequency tail of the wave spectrum should be increased by $\omega$$\^{-3}$ instead of $\omega$$\^{-4}$ or $\omega$$\^{-5}$ for the springing calculation.

• 한국해양공학회:학술대회논문집
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• 한국해양공학회 2004년도 학술대회지
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• pp.173-178
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• 2004

The estimation of springing responses for recent ships are carried out and application to a ship design are described. To this aim, springing effects on hull girder were re-evaluated including non-linear wave excitations and torsional vibrations of the hull. The Timoshenko beam model was used to calculate stress distribution on the hull girder by the superposition method. The strip method was employed to calculate the hydrodynamic forces and moments on the hull. In order to remove the irregular frequencies, we adopted 'rigid lid' on the hull free surface level and added asymptotic interpolation along the high frequency range. Several applications to the existing ships were carried out. They are Bishop and Price's container ship, S-175 container ship, large container, VLCC and ore carrier. One of them is compared with ship measurement result while another with that of model test. Comparison between analytical solution and numerical one for homogeneous beam type artificial ship shows good agreement. It is found that most springing energy came from high frequency waves for the ships having low natural frequency and North Atlantic route etc. Therefore, the high frequency tail of the wave spectrum should be increased by $\omega^{-3}\;instead\;of\;\omega^{-4}\;or\;\omega^{-5}$ for springing calculation.

• Journal of Information Technology Applications and Management
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• 제26권1호
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• pp.77-93
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• 2019

Recently, office workers are increasingly aware of the right to disconnect because of the pressure from strong connections with Internet messengers. In this study, we examined the reason why the perception of the right to disconnect increases and how to deal with it. This research model is that smart working and psychological attachment from work affect right to disconnect, and that open communication and gender moderate the intensity of these effects. To verify this research model, survey questionnaires were distributed to workers in smart working environments, and 400 data were collected and analyzed using Smart-PLS. As results of data analysis, it was verified that smart working and psychological attachment from work had a significant influence on right to disconnect, that open communication group had a lesser effect of psychological attachment from work on right to disconnect than closed communication group, and that women had a lesser effect of psychological attachment from work on right to disconnect than men. Organizations need to maintain a desirable level of right to disconnect in order to improve the quality of working life. But, if it is impossible, They need to change the way of communication more openly so as to absorb the burden of strong connection by Internet. And they need to perform task assignment or stress relief policy reflecting gender characteristics.

• 보건의료생명과학 논문지
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• 제10권1호
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• pp.119-127
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• 2022

본 연구는 농촌지역 거주자의 주관적 건강수준에 영향을 미치는 요인을 파악하고자 수행되었으며, 2019년 지역사회건강조사자료를 기반으로 농촌지역을 무작위로 선정한 후 분석하였다. 주관적 건강수준에 영향을 미치는 요인을 분석한 결과 생물학적요인으로는 연령, 질병력, 성별이, 환경요인으로는 교육수준, 소득수준이, 생활습관요인은 운동, 음주, 수면시간. 흡연, 주관적 스트레스가 그리고 보건의료요인으로는 예방접종, 보건기관이용경험 및 연간 미충족의료경험이 통계적으로 유의하게 나타났다. 생물학적요인의 설명력이 가장 높았고, 생활습관요인이 가장 낮았는데, 특히 흡연, 음주를 하는 경우, 예방접종, 보건기관이용경험이 없는 경우 주관적 건강수준이 높아 건강증진사업을 통해 개선해야 할 부분으로 보인다.

• 한국산학기술학회논문지
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• 제15권6호
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• pp.3685-3695
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• 2014

본 연구는 중학생들의 절망감, 사회심리적 스트레스 및 우울수준과 자살생각 간의 관련성을 파악하며, 또한 자살생각에 유의하게 영향을 미치는 요인들을 규명하고자 시도하였다. 조사대상은 경인 지역의 4개 중학교에서 임의로 선정된 재학생 975명으로 하였으며, 자료 수집은 2013년 5월 1일부터 2013년 6월 30일까지의 조사기간 동안에 구조화된 무기명 자기기입식 설문지(self-administrated questionnaire)를 통해 이루어졌다. 연구결과, 자살생각과 관련 요인들 간의 상관관계를 보면, 자살생각은 절망감, 사회심리적 스트레스 및 우울수준과 유의한 양의 상관관계를 보였다. 다중회귀분석결과, 조사대상자의 자살생각에 관련된 요인으로는 성별, 음주경험여부, 취미 및 여가의 충분성, 주관적 건강상태, 학년, 학교폭력 경험, 절망감의 수준, 사회심리적 스트레스의 수준, 우울수준이 유의한 변수로 선정되었다. 공분산 구조분석 결과, 절망감은 사회심리적 스트레스나 우울수준보다는 자살생각에 더 큰 영향을 미쳤으며, 사회심리적 스트레스, 우울수준 및 절망감이 높아질수록 자살생각을 증가시키는 효과가 있는 것으로 나타났다.