• 한국물환경학회지
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• 제28권2호
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• pp.213-218
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• 2012

Abnormal dissolved oxygen concentration in aquatic habitat, both depletion and supersaturation, can be stress factor to aquatic animals. In this study the nationwide distribution of oxygen supersaturation was analyzed for three categories of streams (43 urban streams, 15 rural streams, and 14 forest streams) by using monitoring network data of the Korean Ministry of Environment. From the distribution analysis 30% of urban streams showed hyperoxic condition of eutrophic level, while no forest stream showed hyperoxic condition. The physiological effect of hyperoxia on fish was examined using two species of fish Zacco koreanus, which resulted in higher concentration of a stress hormone (cortisol) in fish exposed to hyperoxic concentration (196%) of oxygen. This study shows that hyperoxic condition is ubiquitous in urban and rural Korean streams, and it can be a stress factor to aquatic animals.

• 한국조리학회지
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• 제14권2호
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• pp.1-17
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• 2008

This study analyzed the factors related to the stress which the top-rated chefs in Jeju suffer and conducted the multiple regression analysis to look into the effect of job-related stress on the stress reaction and the satisfaction with job, in order to examine the effect of job-related stress faced by hotel kitchen employees in performing duties and determine the effect of job-related stress on the reaction of individuals in the peculiar environment of a kitchen in a hotel. Job-related stresses were classified into five factors which were physical, individual, vocational, organizational, and social. The result of regression analysis, which was performed to figure out the effect of job-related stress on the stress reaction and the satisfaction with the job, indicated that the physical factor of job-related stress had the greatest effect on the physiological reaction, followed by the organizational factor, individual factor, and social factor, while the organizational factor of job-related stress had the greatest effect on the psychological reaction, followed by the individual factor, social factor, vocational factor, and physical factor. Meanwhile, the vocational factor of job-related stress had the greatest effect on behavioral re-action, followed by organizational factor and individual factor. The vocational factor of job-related stress had the greatest effect on the satisfaction with the job, followed by individual factor, organizational factor, social factor, and physical factor.

• 대한가정학회지
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• 제47권1호
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• pp.1-12
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• 2009

The purpose of this study was to establish the relative influences of individual variables (sex, age, temperament) and mother's psychosocial variables (maternal attitude, parenting stress, marriage satisfaction) on daily stress levels and maladjustment of young children attending at daycare centers. Subjects were 224 pairs of children and their mothers, and 18 teachers from 5 child-care centers in Gwangju City. Children were tested individually using 22-item daily stress inventory with illustrations which described certain stressful situations. Questionnaires were also administered to mothers and teachers. Collected data were subjected to Cronbach's $\alpha$, correlation and multiple regression analysis using SPSS (WIN 14.0) program. The major findings were as follows; Overall average score of children's daily stress was equivalent with the median. 'Blame and attack situation' and 'anxiety and frustrated situation' were perceived as more stressful for children than 'lose self-respect situation'. Overall average score of children's maladjustment was lower than the median. 'Overactivity' was highest among subscores of maladjustment. Age was the only significant influential factor on children's daily stress level. Sex was the most influential factor on 'overactivity', 'aggression', and 'regression' of young children. Activity and maternal stress were the second most influential factor on 'overactivity' and 'aggression', respectively.

• Journal of Preventive Medicine and Public Health
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• 제49권5호
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• pp.253-259
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• 2016

Objectives: Central obesity plays a major role in the development of many chronic diseases, including cardiovascular disease and cancer. Chronic stress may be involved in the pathophysiology of central obesity. Although several large-scale genome-wide association studies have reported susceptibility genes for central adiposity, the effects of interactions between genes and psychosocial stress on central adiposity have rarely been examined. A recent study focusing on Caucasians discovered the novel gene early B-cell factor 1 (EBF1), which was associated with central obesity-related traits via interactions with stress levels. We aimed to evaluate EBF1 gene-by-stress interaction effects on central adiposity traits, including visceral adipose tissue (VAT), in Korean adults. Methods: A total of 1467 Korean adults were included in this study. We selected 22 single-nucleotide polymorphisms (SNPs) in the EBF1 gene and analyzed their interactions with stress on central adiposity using additive, dominant, and recessive genetic modeling. Results: The four SNPs that had strong linkage disequilibrium relationships (rs10061900, rs10070743, rs4704967, and rs10056564) demonstrated significant interactions with the waist-hip ratio in the dominant model ($p_{int}$<0.007). In addition, two other SNPs (rs6556377 and rs13180086) were associated with VAT by interactions with stress levels, especially in the recessive genetic model ($p_{int}$<0.007). As stress levels increased, the mean values of central adiposity traits according to SNP genotypes exhibited gradual but significant changes (p<0.05). Conclusions: These results suggest that the common genetic variants for EBF1 are associated with central adiposity through interactions with stress levels, emphasizing the importance of managing stress in the prevention of central obesity.

• 대한교통학회지
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• 제33권6호
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• pp.543-553
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• 2015

본 연구는 대중교통 특히, 버스의 이용과정에서 이용자가 받는 외부 자극(이용환경)이 스트레스(육체적 정신적 부하)에 미치는 영향관계를 분석하였다. 이를 위해 요인분석 및 구조방정식모형(Structural Equation Model)을 이용하였으며, 대전 시내버스 이용자를 대상으로 자료를 수집하였다. 분석결과, 5개 변수 중 탑승혼잡요인이 버스 이용자의 스트레스에 가장 큰 영향을 주는 요인인 것으로 나타났으며(${\beta}=.416$), 다음으로 환승요인(${\beta}=.392$), 운영요인(${\beta}=.265$), 계절요인(${\beta}=.150$), 정류장시설요인(${\beta}=.090$)의 순으로 나타났다. 즉, 이용자의 스트레스는 시설과 운영의 양적인 요인보다는 질적인 서비스 수준 더 큰 관련성이 있는 것으로 분석된 바, 버스정책은 이용자 중심으로 전환되어야 할 것이다. 또한, 스트레스는 이용자특성(성별, 연령, 정기이용여부)에 따라 다르게 나타나므로 보다 세분화된 서비스 제고전략이 유효할 것으로 판단된다.

• 한국주거학회논문집
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• 제8권2호
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• pp.71-84
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• 1997

The Purpose of this study is to estimate how inclination to move can be appeared by understanding the cognition of a resident on stress due to the residential environment. 240 housewives living in Chiniu were Questioned statistical analysis were used with factor analysis, F-test. Duncan's Multiple range analysis, stepwise regression analysis and stepwise discriminant analysis, The result were summarized as follows 1) The stress of residential environment were clissified by six factors indoor facility, educational environmental. indoor structure, air Pollution noise, traffic convenience. 2) The extent of a stress from residential environment was significantly different in the socio-demographic variable and housing-related variable. 3) The stress of residential environment were affected by the direction of house. 4) The variable discriminating inclination to move were the stress of residential environment(air Pollution). an educational level, the type of housing possession, residential Period and the size of house.

• 한국산학기술학회논문지
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• 제13권2호
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• pp.554-561
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• 2012

본 연구는 임상실습 시 스트레스에 따른 불안, 분노, 피로정도를 알아보고 이들 간의 공통적인 주제를 모색하여 이들 간의 상관관계를 분석하여 효율적인 임상실습을 도모하기 위한 기초자료를 제공하기 위한 것이다. 연구대상은 T종합병원에서 임상실습을 하는 간호학생 197명으로 수집된 자료는 SPSS Win 17.0 프로그램을 이용하여 t-test, ANOVA, pearson's correlation coefficient로 분석하였다. 결과적으로 임상실습 스트레스 정도는 평균3.82점, 불안은 평균 48.82점, 분노는 평균 1.17점, 피로는 평균 30.96점으로 나타났으며 불안 정도와 통계적으로 유의한 차이를 보이는 임상실습 스트레스 요인은 집담회, 수업과 실습, 임상실습만족도로 나타났다. 분노 정도와 유의한 차이를 보이는 임상실습 스트레스 요인은 과제물, 수업과 실습, 오리엔테이션, 간호사, 실습환경이며, 피로와 유의한 차이를 보이는 임상실습 스트레스 요인은 집담회, 오리엔테이션, 실습환경, 환자로 나타났다. 결론적으로 임상실습 스트레스와 불안, 분노, 피로정도, 분노와 피로 정도는 유의한 상관관계로 나타났으며 불안과 분노 정도는 유의한 상관관계를 보이지 않았다.

• Structural Engineering and Mechanics
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• 제81권5호
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• pp.565-574
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• 2022

The infrastructures such as offshore, bridges, power plant, oil and gas piping and aircraft operate in a harsh environment during their service life. Structural integrity of engineering components used in these industries is paramount for the reliability and economics of operation. Two regression models based on the concept of Gaussian process regression (GPR) and Minimax probability machine regression (MPMR) were developed to predict stress intensity factor range (𝚫K). Both GPR and MPMR are in the frame work of probability distribution. Models were developed by using the fatigue crack growth data in MATLAB by appropriately modifying the tools. Fatigue crack growth experiments were carried out on Eccentrically-loaded Single Edge notch Tension (ESE(T)) specimens made of API 5L X65 Grade steel in inert and corrosive environments (2.0% and 3.5% NaCl). The experiments were carried out under constant amplitude cyclic loading with a stress ratio of 0.1 and 5.0 Hz frequency (inert environment), 0.5 Hz frequency (corrosive environment). Crack growth rate (da/dN) and stress intensity factor range (𝚫K) values were evaluated at incremental values of loading cycle and crack length. About 70 to 75% of the data has been used for training and the remaining for validation of the models. It is observed that the predicted SIF range is in good agreement with the corresponding experimental observations. Further, the performance of the models was assessed with several statistical parameters, namely, Root Mean Square Error (RMSE), Mean Absolute Error (MAE), Coefficient of Efficiency (E), Root Mean Square Error to Observation's Standard Deviation Ratio (RSR), Normalized Mean Bias Error (NMBE), Performance Index (ρ) and Variance Account Factor (VAF).

• 한국지역사회생활과학회지
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• 제17권3호
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• pp.29-41
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• 2006

The purpose of this research is to study the causal model among mother related variables, child abuse, and children's emotional maladjustment behaviors. The sample subjects were 542 pairs of fifth and sixth grade elementary school students and first as well as eighth grade middle school students, and their mothers. The major findings of the research are as follows: First, the result of multiple regression analysis on the effects of the maternal parenting stress and marital satisfaction to the children's abuse indicates that stress related to learning expectation and stress related to relationship with child are the significant contributing factor to physical abuse and verbal abuse. Second, the result of multiple regression analysis on the effects of the maternal parenting stress and child abuse to the children's emotional maladjustment behaviors indicate that verbal abuse is the significant contributing factor. Third, looking at causal relations of the maternal variables (maternal parenting stress, marital satisfaction) and child abuse (physical abuse, verbal abuse, neglect) to the children's emotional maladjustment behaviors, maternal variables impact indirectly through the child abuse factor.

• Coupled systems mechanics
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• 제12권2호
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• pp.151-165
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• 2023

In this study, a simple method for the determination of the shear correction factor for composites beam with a rectangular cross section is presented. The plane stress elasticity assumption is used after simplifications of the expression of the stress distribution in the beam. The different fiber orientation angle and volume fraction are considered in this work. The studied structure is subjected to various loading type (thermal and hygrothermal). The numerical results obtained show that there is a dependence of the shear coefficient on the orientation of the fibers. The evolution of the shear correction factors depends not only on the orientation of the fibers and also on the volume fraction and the environment. the advantage of this developed formula of the shear correction factor is to obtain more precise results and to consider several parameters influencing this factor which are neglected if the latter is constant.