• Proceedings of the Korea Concrete Institute Conference
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• 2005.05b
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• pp.65-68
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• 2005

Social requirements to the civil and building structures have been changed in accordance with the social and economic progress. It is very important to develop the innovative structural materials and tecnology that the social requirements appropriately. Ductility of High Performance Fiber Reinforced cementitious Composites (HPFRCC), which exhibit strain hardening and multiple crackling characteristics under the uniaxial tensile stress are drastically improved. Because ductility in tensile test are very different according to specimen shapes, three types of the direct tensile test are performed. The tensile test are performed using the tensile test specimen, dummbell-shaped specimen, and cylinder specimen. As a result, tensile performance in HPFRCC is very good comparing to cylinder specimen because of direction characteristics of fibers. It is necessary to clarify the examination method of suiting to the usage.

• KEPCO Journal on Electric Power and Energy
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• v.6 no.1
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• pp.41-47
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• 2020

The contribution of damage mechanisms to failure of steam turbine casing made of Cr-Mo-V steel was investigated. Creep-fatigue interaction on the HP side corner of turbine casing was revealed as the root cause of the catastrophic failure performed by metallurgical analysis. The steady-state pressure and transient thermal stress were analyzed based on the actual operating condition of the thermal plant. Damage of creep-fatigue interaction to crack initiation was evaluated with multiaxial effects. The contribution ratio of creep and fatigue to the crack initiation was estimated to 3:1. Temporary geometrical correct action with repair weld was executed. For long-term operation, design improvement of casing equipment for creep resistance should be needed.

• Journal of Families and Better Life
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• v.13 no.1
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• pp.12-25
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• 1995

본 연구는 수험생 자녀를 둔 가족의 정신, 신체적 건강이 크게 위협받고 있음을 중시하고, 부모와 수험생 자녀가 겪는 스트레스를 인지, 대처, 디스트레스의 각 측면으로 측정하고 관련 변인을 분석함으로써, 이들 가족의 스트레스 극복을 위한 적절한 방안을 강구해보고자 하는데 그 목적을 두고 고등학교 3학년 재학생과 그 부모 3인을 한쌍으로 360가족, 1080명을 대상으로 자료수집 하였으며, 주요 분석결과는 다음과 같다. 1) 자녀의 학업스트레스가 가장 높게 나타났으며 다음은 모, 부의 순으로 나타났으나 모, 부간의 차이가 크지 않아 부, 모, 자녀의 순으로 대처능력이 높게 나타나 자녀는 높은 스트레스를 인지하면서도 적절한 대체방안을 사용하지 못하고 있음을 알수 있다 2) 부모자녀의 스트레스 상관도는 자녀의 경 우 스트레스 인지와 디스트레스간의 상관이 비교적 높고 부모의 경우는 스트레스 대처와 디스트레스간의 상관이 높다. 또한 부부간 스트레스는 상관이 높지만 부모 자녀간에는 상관이 높지 않게 나타나고 있다. 3) 자녀의 지원대학 수준모의 학력이나 가족의 소득부의 직업 수준등이 낮은 경우 부모나 수험생 자녀의 스트레스가 높게 나타나고 가족응집성, 자녀의 자아 정체감 학업성취욕, 부모의 결혼만족도, 부와의 친밀성, 부모 자녀 갈등등은 스트레스 수준에 영향을 미치는 중요변인이며 이러한 영향력은 모두 자신의 지각에 따라 반응한다.

• Journal of Advanced Marine Engineering and Technology
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• v.7 no.1
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• pp.79-90
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• 1983

The examination for the changes of structures and mechanical properties in directionally solidified Al-Fe-Ni alloys containing the small amount of Fe and Ni was carried out by the varying the composition and solidification rate R of alloy, provided that the temperature gradient was 80 .deg.C/cm. The result were obtained as follows. A) In proportion to the increase of the solidification rate (R), the crystallized phase of this alloy was changed from the Ribbon-type structure to the Rod-type structure. B) The strength was rapidly increased in the changing process of composite shape from the Ribbon-type to the Rod-type with the solidification rate (R) increasing. C) The fiber stress (${\sigma}^f$) and Young's modulus ($E_f$) calculated for the Rod-type structure were 220 kg/$mm^2$ and 11, 800 kg/$mm^2$ respectively, which were in good accord with the rule of Mixtures.

• Nuclear Engineering and Technology
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• v.49 no.3
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• pp.651-661
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• 2017

The Korea Institute of Nuclear Safety, as a representative organization of Korea, in February 2012 participated in an international Program to Assess the Reliability of Emerging Nondestructive Techniques initiated by the U.S. Nuclear Regulatory Commission. The goal of the Program to Assess the Reliability of Emerging Nondestructive Techniques is to investigate the performance of emerging and prospective novel nondestructive techniques to find flaws in nickel-alloy welds and base materials. In this article, Korean round-robin test results were evaluated with respect to the test blocks and various nondestructive examination techniques. The test blocks were prepared to simulate large-bore dissimilar metal welds, small-bore dissimilar metal welds, and bottom-mounted instrumentation penetration welds in nuclear power plants. Also, lessons learned from the Korean round-robin test were summarized and discussed.

• Journal of Korean Public Health Nursing
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• v.35 no.1
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• pp.60-71
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• 2021

Purpose: This study examined the socio-demographic and health factors affecting the quit-smoking plan in smoking seniors. Methods: Data were obtained from the Seventh Korean National Health and Nutrition Examination Survey (VII-1, VII-2, VII-3). The sample consisted of 369 smoking seniors. The complex sample was analyzed thought an independent t-test, Chi-square test, and multiple logistic regression. Results: The influential factors on the quit-smoking plan were daily smoking (OR=0.30, CI=0.11-0.78), age of start smoking (OR=1.06, CI=1.01-1.11), daily smoking amount (OR=0.95, CI=0.90-1.00), quit-smoking trial (OR=2.63, CI=1.32-5.23), and cognitive stress (OR=2.13, CI=1.01-4.54). Conclusion: This study revealed the variables that should be considered when setting up a smoking cessation plan for smoking seniors. Based on this, an elderly cessation intervention program can be developed.

• The Korean Journal of Health Service Management
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• v.12 no.4
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• pp.139-154
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• 2018

Objectives: The aim of this study was to examine factors influencing health-related quality of life of waged workers. Methods: This study used data from the Seventh Korea National Health and Nutrition Examination Survey. Data were analyzed with the $x^2-test$, t-test, ANOVA, and multiple regression. Results: The significant predictors of health-related quality of life were depression, subjective health status, age, activity limitation, education, worker status, monthly income, drinking, smoking, physical injury, stress, and moderate physical activity. Conclusions: Personal health characteristics, psychological characteristics, socioeconomic characetrictics and working characetrictics affect health-related quality of life. Health-related quality of life is also affected by social structural problems such as socioeconomic factors and employment instabilitye. In addition to the development of health care programs to improve health-related quality of life of twaged workers, policy changes are needed to improve the social structure.

• Journal of Yeungnam Medical Science
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• v.39 no.2
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• pp.150-152
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• 2022

Complications related to the vascular anastomosis of the placental vessels in monochorionic twins are fatal. The clinical syndromes of feto-fetal transfusion include twin anemia polycythemia sequence (TAPS), twin-twin transfusion syndrome, and twin reversed arterial perfusion sequence. We present an extremely rare case of TAPS in a dichorionic diamniotic pregnancy. A 36-year-old woman, gravida 0, para 0, was referred to our hospital with suspected preterm premature membrane rupture. Although her pelvic examination did not reveal specific findings, the non-stress test result showed minimal variability in the first fetus and late deceleration in the second one. An emergency cesarean section was performed. The placenta was fused, and one portion of the placenta was pale, while the other portion was dark red. The hemoglobin level of the first fetus was 7.8 g/dL and that of the second one was 22.2 g/dL.

• Korean Journal of Health Education and Promotion
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• v.18 no.2
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• pp.27-44
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• 2001

In this study, I investigate the drinking behavior and related factors among white collar workers in seoul. Examination was executed with questionnaire to 520 white collar workers. Drinking behavior involves frequency of drinking, amount of alcohol consumption in a drinking situation and alcohol-related problem. Related factors involves the general characteristics, the knowledge about alcohol, the allowable attitude about drinking, work stress and stress copying. This was analyzed with percentage, mean, standard deviation, t-test, ANOV A and pearson's correlation. The results are as follows: Data shows that about 96.3% of the respondents drink at least during the last year and 89.8% of the respondents drink at least during the last month. 59.4% male respondents drink 3-8 times a month, 44.8% female respondents drink 1-2 times a month. High prevalence rates were found in male, married person and those with low-religious spirit in a usual amount of drinking(p〈0.05), male in the latest amount of drinking(p〈0.05), male, forties, married person and those with the highest monthly family income and those with low-religious spirit in frequency of drinking during the latest month(p〈0.05). The score of alcohol-related problem(ARP) was as follows: male workers-2.61, female workers-1.61 out of 35. The score of ARP was statistically significantly different according to sex(p〈0.05). A positive correlation was observed between amount of drinking, frequency of drinking and ARP(p〈0.01). The score of knowledge about alcohol was 3.6 and any correlation and statistically significant difference were not observed between the knowledge about alcohol and drinking behavior. The score of allowable attitude about drinking was statistically significantly different according to sex(p〈0.05), age(p〈0.05). A positive correlation was observed between attitude about drinking and amount of drinking, frequency of drinking, ARP(p〈0.01). The work stress and stress copying had no significant relations with drinking behavior. Most respondents do not drink at stress situation.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.7
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• pp.365-374
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• 2017

This study examined the effects of the demographic and health characteristics and chronic diseases on the health-related quality of life in service employees. From January 1, 2013 to December 31, 2014, this study analyzed the data on 607 service employees based on the 2nd data of the 6th National Health and Nutrition Examination Survey with at-test, ANOVA, and hierarchical regression analysis use of SPSS. The results of the analysis showed that the quality of Life in women was lower (${\beta}=-.074$, p=.050) than that of men, and the older the subjects were, the lower their quality of life(${\beta}=307$, p=.000). Regarding the subjective health status, there was a significant increase in the "very Poor"(${\beta}=186$, p=0.027) and "good"(${\beta}=196$, p=.001) status. The quality of life improved with increasing activity (${\beta}=-0.222$, p=0.000)). Some of the subjects perceived "high stress" (${\beta}=-0.123$, p=0.003) and the others perceived "low stress"(${\beta}=-0.176$, p=0.000). The less they perceived stress, the higher their quality of life. The factors explained 24.6％ of the health-related quality of life of the subjects. Therefore, to improve health-related quality of life of service employees, more activity opportunities should be given, the subjective health status should be positively perceived and psychological measures to decrease the level of stress should be developed.