• Nuclear Engineering and Technology
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• 제55권8호
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• pp.2823-2834
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• 2023

Austenitic stainless steel welds (ASSWs) of nuclear components undergo aging-related degradations caused by high temperature and neutron radiation. Since irradiation leads to the change of material characteristics, relevant quantification is important for long-term operation, but limitations exist. Although ion irradiation is utilized to emulate neutron irradiation, its penetration depth is too shallow to measure bulk properties. In this study, a systematic approach was suggested to estimate mechanical properties of ion irradiated 308 ASSW. First of all, weld specimens were irradiated by 2 MeV proton to 1 and 10 dpa. Microstructure evolutions due to irradiation in δ-ferrite and austenite phases were characterized and micropillar compression tests were performed. In succession, dislocation density based stress-strain (S-S) relationships and quantification models of irradiation defects were adopted to define phases in finite element analyses. Resultant microscopic S-S curves were compared to verify material parameters. Finally, macroscopic behaviors were calculated by multiscale simulations using real microstructure based representative volume element (RVE). Validity of the approach was verified for the unirradiated specimens such that the estimated S-S curves and 0.2% offset yield strengths (YSs) which was 363.14 MPa were in 10% agreement with test. For irradiated specimens, the estimated YS were 917.41 MPa in 9% agreement.

• Human Ecology Research
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• 제61권4호
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• pp.635-645
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• 2023

This study examined the trends of domestic academic research on children of divorced families by classifying them by period, method, target, and subject. From 2000 to 2022, 105 papers published in 58 journals were surveyed. In terms of research methods, quantitative research was conducted using questionnaires and panel data. The subjects of the reviewed studies were mainly elementary school children, and there were many studies on both divorced single mother and child families as well as divorced single father and child families. By analyzing the core subjects of the study, papers related to children's personal adaptation accounted for the largest proportion, followed by problematic behaviors, psychological difficulties, such as depression and stress, and relationships. In conclusion, due to the high divorce rate in Korea there is a need to focus academic attention on the children of divorced families. To this end, it is necessary to study the adaptation and protection factors of the children of divorced families. More qualitative research should be conducted on children of divorced families of various ages, not just elementary school students.

• 한국콘텐츠학회논문지
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• 제22권2호
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• pp.695-709
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• 2022

본 연구는 코로나19 이후 가정 내 식사 비중이 증가함에 따라 어머니들이 식사준비 시 느끼는 스트레스와 먹거리 소비패턴 변화를 조사하기 위해 20세 이하의 미성년 자녀를 둔 30~40대 어머니를 대상으로 개별적인 심층면담을 통한 질적연구를 수행하였다. 주요 결과를 요약하면 다음과 같다. 코로나19 이후 대면 교육의 확대로 자녀들이 가정에 머무르는 시간이 길어지면서 어머니의 직업유무에 상관없이 식사준비가 스트레스로 작용하고 있었다. 외식 빈도는 현저히 감소한 반면, 가정 내 배달음식 이용과 온라인 장보기 빈도는 크게 증가했음에도 불구하고 배달음식의 위생문제와 영양불균형에 대한 우려로 자녀의 식사는 신선한 음식으로 골고루 직접 준비하고자 하였으며, 특히 자녀의 연령이 낮을수록 이러한 경향이 높았다. 먹거리 소비 결정요인을 분석한 결과, 어머니들의 연령이 낮고 가구소득이 높을수록 유기농 먹거리에 대한 관심이 높았으며, 학력이 낮을수록 먹거리 및 건강관련 정보에 무관심한 태도를 보였다. 건강에 대한 관심 증가로 건강기능식품을 이전에 비해 꾸준히 섭취하고 있었으며, 백신을 미접종한 자녀의 면역력 향상을 위해 건강기능식품을 추가로 구매한 경우가 많았다. 이상의 결과를 바탕으로 영유아나 어린이를 대상으로 한 다양한 유기농 밀키트 제품의 개발과 함께 고위험시대에 대응하기 위한 건강하고 안전한 가정 내 먹거리 지침 및 식생활관련 교육의 필요성을 제기하는 바이다.

• 한국콘텐츠학회논문지
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• 제21권5호
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• pp.627-637
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• 2021

우리나라는 신체적 위해 뿐만 아니라, 사회경제적으로도 규모와 심각도를 더해가고 있는 음주폐해의 감소를 위해 다양한 방안들을 모색하고 있다. 그 중에서도 개인들의 음주행태 개선은 음주폐해를 줄이는 가장 직접적인 방법이다. 외국에서는 '보호행동전략'의 사용이 음주폐해를 줄이는 효과적인 방안으로 알려져 있는데, 우리나라에서는 성인을 대상으로 이를 조사하여 검증한 연구들이 매우 부족하다. 따라서 본 연구는 보호행동전략의 사용이 음주폐해 감소에 유의한 영향을 끼치는지를 확인하고자 하였다. 전국 성인 남녀 2,000명을 대상으로 한 연구 결과, 보호행동전략의 사용은 음주폐해를 줄이는 것으로 나타났으며, 음주폐해에 가장 큰 영향을 끼친 것은 심각한 폐해감소 전략 영역이었고, 다음으로 음주방법 제한 영역이었다. 음주량 감소 영역의 영향은 유의하지 못한 것으로 나타났다. 이 외에도 음주빈도, 폭음, 음주 동기는 음주폐해에 정적인 영향을 끼쳤으며, 사교 동기의 경우만 부적인 영향을 끼쳤다. 본 연구에서는 향후 종단연구를 통한 면밀한 요인들 간의 관계 파악, 대상층을 세분화한 보호행동전략 사용 강화 방안에 관한 후속 연구들을 제안하였다.

• 한국조리학회지
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• 제22권3호
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• pp.139-154
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• 2016

본 연구 외식조리전공 대학생들의 음주 행위에 대한 부정적 인식과 긍정적 인식이 학교생활 만족도와 스트레스에 대한 관계 연구이다. 대학생활중에 음주습관과 행위는 곧바로 사회생활로 이어진다는 데서 그 심각성이 더 크다고 볼 수 있으며, 특히 조리와 같은 특수 직업분야에서 음주습관은 향후 경력관리에도 영향을 끼친다고 볼 때, 본 연구의 결과를 적용하는 것은 매우 효과적일 것으로 사료된다. 연구결과, 음주에 대한 긍정적 인식과 부정적 인식 모두 학교생활 만족도 및 스트레스와 매개 효과 연관성이 통계적으로 유의하게 나타났으며, 특히 음주에 대한 긍정적 인식은 학교생활 연관성과 ${\beta}=-.219$, p<0.01로 부(-)의 관계를 나타냈다. 음주에 대한 부정적 인식은 통계수준 ${\beta}=.445$, p<0.01에서 정(+)의 영향을 미치며, 역시 만족도와 스트레스에서도 ${\beta}=.213$, p<0.01 유의성을 보이고 있다. 음주 빈도나 습관에 있어서는 남녀 차이가 없으며, 이러한 결과는 전통적으로 남자가 음주에 더 많이 노출될 수 있다는 고정관념이 사라지고, 음주는 남녀 모두의 문제로 대두되었다는 것을 보여주는 예가 될 것이다. 연구의 시사점으로 대학전공을 구체적으로 연구를 하였지만, 졸업 후 직업을 가지고 업무를 수행하는 과정에서 나타나는 음주 행위와 어떠한 연관성을 갖는지를 파악하는 지속적 연구인 종단 연구가 필요하다.

• 디지털융복합연구
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• 제15권3호
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• pp.237-245
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• 2017

본 연구는 여고생의 신체존중감, 비만스트레스, 자아존중감과 체중조절행위와의 관련성을 파악하고, 건강한 체중조절행위를 유도하기 위한 효과적인 프로그램 개발의 기초자료를 제공하기 위한 서술적 상관관계 연구이다. 본 연구의 대상자는 B와 J시에 소재하고 있는 2개 고등학교에 재학중인 여고생을 대상으로 하였으며, 체중조절행위 경험이 없거나 실제 BMI가 저체중으로 파악된 설문지를 제외한 135부를 최종 분석에 사용하였다. 수집된 자료는 IBM SPSS Statistics 20.0 프로그램을 사용하여 기술통계, t-test 혹은 one-way ANOVA, Pearson's correlation coefficient를 통해 분석하였다. 연구결과 대상자의 불건강한 체중조절행위는 신체존중감(r=-.18, p<.05), 비만스트레스(r=.39, p<.001), 자아존중감(r=-.32, p<.001)과 유의미한 상관관계가 있는 것으로 나타났다. 본 연구결과를 바탕으로 여고생의 건강한 체중조절행위를 유도하기 위해서는 신체존중감, 비만스트레스 및 자아존중감 변수를 고려한 융복합적 프로그램 개발이 필요할 것으로 생각된다.

• 가정과삶의질연구
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• 제25권3호
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• pp.89-106
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• 2007

This paper diagnoses the financial knowledge of the college students and their values on financial situation. Another emphasis is given to the classification of surveyed college students based on their financial knowledge and values and the financial traits of each classified group is also analyzed. Statistical analysis was conducted using Cronbach's ${\partial}$, factor analysis, t-test, one-way ANOVA, and Duncan's multiple range test with total number of 733 questionnaires. Primary results of the research are as follows: First, overall score of financial knowledge was 62.65 points, showing the highest points in spending while lowest in savings and investment. Senior classes, students majoring in liberal arts, students with financial education and media experiences scored high points. Second, overall score of college students on financial values was 3.92, resulting in high points on credit and frugality but points on sharing with others were low. Thirdly, all surveyed students were classified into 4 types based on the mean scores on financial knowledges and values. Total 31.7% of students belonged to Type 1 where students scored high points on financial knowledge and values. Type 2 had about 22.4 % of students whose financial score was high but value score was low. Type 3 occupied 24.2% and this group scored low points on financial knowledge but high points on financial values. Type 4 occupied 21.8% and was a group of students whose scores for financial knowledge and values were low. Finally, Type 1 and 3 groups showed better desirable behaviors for financial management and expressed higher satisfaction status for finance than Type 2 and 4. Type 1 is a group of students whose subjective financial level was high. Monthly income was highest in Type 2 and financial stress was lowest in Type 1.

• 한국도로학회논문집
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• 제16권6호
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• pp.95-104
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• 2014

PURPOSES : The purpose of this study is to evaluate the degree of restraint (DOR) of longitudinal steel at continuously reinforced concrete pavement (CRCP) against environmental loadings. METHODS : To measure the longitudinal steel strain, 3-electrical resistance and self-temperature compensation gauges were installed to CRCP test section (thickness = 250mm, steel ratio = 0.7%) and continuously measured 10 min. intervals during 259 days. In order to properly analyze the steel strains first, temperature compensation process has been conducted. Secondly, measured steel strains were divided into 12 phases with different events such as before paving, during concrete hardening, and after first cracking, etc. RESULTS : Thermal strain rate (TSR) concept is defined as the linear strain variations with temperature changes and restraints rate of longitudinal steel against environmental loadings (especially thermal loading) with different cases is defined as degree of restraint(DOR). New concept of DOR could be indirect indicator of crack width behaviors of CRCP. CONCLUSIONS : Before paving, DOR of longitudinal steel is almost same at the coefficient of thermal expansion of steel ($12.44m/m/^{\circ}C$) because of no restraint boundary condition. After concrete pouring, DOR is gradually changed into -1 due to concrete stiffness developing with hydration. After first cracking at crack induced area, values of DOR are around -3~-5. The negative DOR stands for the crack width behavior instead of steel strain behavior. During winter season, DOR reached to -5.77 as the highest, but spring this values gradually reduced as -1.7 as the lowest. Based on this observation, we can presume crack width decreased over time within the time frame of this study. This finding is not consistent with the current theory on crack width variations over time, so further study is necessary to identify the causes of crack width reducing. One of the reasons could be related to concrete stress re-distribution and stress relaxation.

• Asian-Australasian Journal of Animal Sciences
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• 제14권2호
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• pp.288-296
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• 2001

The behavior of declawed emus in a farm environment has not been described despite its importance in the husbandry and welfare of the emu. This study examined whether declawing of emus causes chronic pain resulting in permanent changes in the locomotor and general behavior of declawed yearling emus compared to emus not declawed. One group of 40 emus were declawed on the day of hatch by removing the distal phalangeal joint using a Lyon beak-trimming machine. Another group of 40 emus not declawed were the controls. Declawed emus one year of age were allocated to a paddock $250m{\times}125m$, while the control group was placed in an adjoining paddock of the same dimensions. One hour video records of individual emus from each treatment were made from 08:00 and 17:00 h over 2 periods; firstly when food and water was available and secondly during a period when food and water was not available after being withdrawn overnight. Inactive, ingestive, posture change, grooming, aggressive and locomotor behaviors were monitored from the videotape. There was no behavioral evidence to indicate loss of locomotor ability of declawed emus or to suggest declawed emus were suffering from severe chronic pain as indicated by declawed emus engaging in significantly more bouts (p<0.05) and time of searching (p<0.05). Declawed emus also engaged in less stereotype pacing (p<0.05) indicating they were under less stress and not as frustrated as control birds which engaged in more step pushing behavior (p<0.05). Modelling analysis showed that pecking behavior in birds was most closely related to foraging behavior. Birds subject to pecking attacks demonstrated higher levels of stereotype behavior presumably as a method to cope with stress. The behavioral evidence in this study would indicate that declawing does not compromise the locomotor ability of emus and has the benefit of improving the social structure in the groups by reducing stereotype behavior and aggression.

• 한국보건간호학회지
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• 제35권1호
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• pp.89-103
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• 2021

Purpose: This study examined the factors associated with depression among Korean graduate students. Specifically, personal (self-efficacy, stress), environmental (violence experience, economic state, and relationship conflict), and behavioral (health behavior) factors were analyzed. Methods: This study used a cross-sectional study design. One hundred and fifty participants currently enrolled in graduate programs were recruited. Google Drive was used for online data collection. Descriptive statistics, correlational analyses, and hierarchical regression analysis were conducted. Results: First, 52% of the participants were male, with an average age of 28.05(±3.19). Master's students comprised the largest proportion (63.3%). Approximately about 38.7% were engineering majors. Second, approximately 27.3% had depressive symptoms; and 7.3% had major depression. Third, there was a significant correlation between personal, environmental (financial burdens), and behavioral factors. Fourth, hierarchical regression analysis revealed a lower depression level to be associated with a higher self-efficacy level and health behavior. In contrast, a higher depression level was related to violence experience. Conclusion: The government should press on establishing rules on the prevention and regulation of violence in universities, and impose strong disciplinary measures to root out the problem. In addition, universities must pay attention to the mental health of graduate students and establish systems to manage them.