• 한국압력기기공학회 논문집
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• 제13권1호
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• pp.75-83
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• 2017

This study investigated deformation behavior of major nuclear structural materials under cyclic loading conditions via cyclic stress-strain test. The cyclic stress-strain tests were conducted on SA312 TP316 stainless steel and SA508 Gr.3 Cl.1 low-alloy steel, which are used as materials for primary piping and reactor pressure vessel nozzle respectively, under cyclic load with constant strain amplitude and constant load amplitude at room temperature (RT) and $316^{\circ}C$. From the results of tests, the cyclic hardening and softening behavior, stabilized cyclic stress-strain behavior, and ratcheting behavior of both materials were investigated at both RT and $316^{\circ}C$. In addition, appropriate considerations for cyclic deformation behavior in the structural integrity evaluation of major nuclear components under excessive seismic condition were discussed.

• 한국구조물진단유지관리공학회 논문집
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• 제25권5호
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• pp.149-156
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• 2021

FRP 보강근은 철근-콘크리트 부재의 부식 문제를 해결하기 위해 제안되어왔으나, FRP는 높은 인장강도, 낮은 연성 및 선형 탄성 거동으로 인해 하중이 전달될 때 콘크리트와 보강재 사이의 부착 메커니즘이 다르다. 그러므로, FRP-Rebar와 콘크리트 사이의 부착 거동은 주의 깊게 검토해야 한다. 이를 위해 직접 인발 실험이 간단하게 부착 거동을 평가할 수 있으므로 사용됐으나, 직접인발의 실험 결과는 실제 FRP를 보강근으로 사용한 콘크리트 부재의 휨-부착 거동과 다르다. 그러므로 실제 휨-부착 거동을 평가할 방안이 필요하다. 본 연구에서는 FRP를 보강근으로 사용한 콘크리트 부재의 휨-부착 거동에 대한 평가방법을 검토하고 비교하였다. 그 결과, 겹침이음이 있는 부재의 실험 방법이 실제 휨-부착 특성을 잘 반영할 수 있으나 다른 실험방법보다 시험체의 단면 및 지간이 커야 하고 시험체의 설계 및 해석이 복잡하다. 한편, 아치가 있는 부재 실험은 모멘트 팔길이의 변화를 무시하는 평형 방정식을 기반으로 한 힌지가 있는 부재 실험과 달리 콘크리트의 영향을 반영할 수 있으나, 휨-부착에 의한 파괴 이전에 전단파괴의 우려가 있다.

• Computers and Concrete
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• 제26권6호
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• pp.587-593
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• 2020

In this study, bond behavior of ordinary concrete and rebars with different diameters and development length was investigated by using Hinged Beam Test (HBT) and Eccentric Pull-Out Test (EPT) comparatively. For this purpose, three different rebar size and development length depending on rebar diameter were chosen as variables. Three specimens were produced for each series of specimens and totally 54 specimens were tested. At the end of the tests it was observed that obtained results for both tests were quite similar. On the other hand, increased bar size, especially for the specimen with 14 mm bar size and 14 development length (lb), caused shear failure of test specimens. This situation infers that when bigger bar size and lb are used in such test, dimensions of test specimens should be chosen bigger and stirrups should be used for producing of test specimens to obtain more adequate result by preventing shear failure. Also, a nonlinear regression analysis was employed between HBT and EPT results. There was a high correlation between the EPT values, lb, rebar diameters and estimated theoretical HBT. In addition, at the end of the study an equation was suggested to estimate bond strength for HBT by using EPT results.

• 한국학교ㆍ지역보건교육학회지
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• 제13권3호
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• pp.87-100
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• 2012

Objectives: The purpose of this descriptive study was to investigate self-efficacy, health promotion behavior intention, and health promotion behavior in middle school students. Methods: The data were collected by a questionnaire given to the students. The participants for this study were 564 students from four middle school located in Busan. Descriptive statistics, t-test or ANOVA with Scheff$\acute{e}$ test and Pearson's Correlation Coefficients were used for data analysis with SPSS Win 18.0. Results: The level of self-efficacy and health promotion behavior intention was moderate. health promotion behavior was also relatively moderate. The score of health promotion behavior was affected by various general characteristics and health promotion behavior showed weakly positive correlation with self-efficacy, but there was no significant correlation between health promotion behavior intention and health promotion behavior. Conclusion: The findings from this study indicated a need to develop a nursing intervention program to promote health promotion behavior in middle school students including the promotion of self-efficacy.

• Advances in concrete construction
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• 제9권3호
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• pp.289-299
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• 2020

To investigate the long-term behavior of eccentrically loaded RC columns, which are more realistic in practice than concentrically loaded RC columns, long-term eccentric loading tests were conducted for 10 RC columns. Test parameters included concrete compressive strength, reinforcement ratio, bar yield strength, eccentricity ratio, slenderness ratio, and loading pattern. Test results showed that the strain and curvature of the columns increased with time, and concrete forces were gradually transferred to longitudinal bars due to the creep and shrinkage of concrete. The long-term behavior of the columns varied with the test parameters, and long-term effects were more pronounced in the case of using the lower strength concrete, lower strength steel, lower bar ratio, fewer loading-step, higher eccentricity ratio, and higher slenderness ratio. However, in all the columns, no longitudinal bars were yielded under service loads at the final measuring day. Meanwhile, the numerical analysis modeling using the ultimate creep coefficient and ultimate shrinkage strain measured from cylinder tests gave quite good predictions for the behavior of the columns.

• 지역사회간호학회지
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• 제21권2호
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• pp.156-168
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• 2010

Purpose: The purpose of this study was to construct a questionnaire to assess male workers' sobriety behavior based on Ajzen's Theory of Planned Behavior (TPB). Methods: A primary questionnaire with 56 questions was constructed based on literature review and structured interview with male workers. The Content Validity Index (CVI) was evaluated by a group of experts, construct validity was tested by principle component analysis, and reliability was evaluated by Cronbach's ${\alpha}$ and the test-retest reliability test. Results: Fifty two questions showed higher than .8 of CVI. Four factors explained 78.71% of the total variance among items for sobriety intention and direct measure, and six factors explained 67.99% of the total variance among indirect measure items and those factors coincided with the variables of TPB in factor analysis. Cronbach's ${\alpha}$ of this questionnaire was .873 and the result of test-retest reliabilty test was relatively reliable. A total of 41 items with 7-point scale were constructed in the final version. Conclusion: This questionnaire was valid and reliable to measure sobriety behavior based on TPB in male workers. It can be useful to evaluate the result of a sobriety program for male workers.

• 한국간호교육학회지
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• 제18권3호
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• pp.393-402
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• 2012

Purpose: This study was conducted to test the effect of a Career Search Program on career search efficacy, career search behavior, and career decision making for nursing students. Methods: A non-equivalent pre-post test of a quasi-experimental design was used. Fifty first grade nursing students participated in the study with 22 in the experimental group and 28 in the control group. We used a Career Search Program which was held 6 times over 6 weeks, 90 minutes per session. Descriptive statistics, ${\chi}^2$-test, and independent t-test were used for statistical analysis with SPSS 19.0. Results: There were significant increases in career search efficacy (t=2.07, p=.044) and career search behavior(t=2.65, p=.011) in the experimental group compared to the control group. However, career decision making was not significantly changed (t=0.96, p=.342). Conclusion: These results suggest that a Career grade Search Program has an effect on increasing career search efficacy and career search behavior in first grade nursing students. In addition, more programs to impact career decision making should be developed for nursing college students.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1997년도 가을 학술발표회 논문집
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• pp.603-608
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• 1997

Studies on the second-order analysis of reinforced concrete columns have been chiefly dealt with symmetric section under uniaxial loading. In practical situations, however, columns are subjected to biaxial loadings. Therefore, for more accurate prediction of the behavior of concrete columns under biaxial loading, the interaction between bending moments of major and minor axes should be considered. Recently Kim & Lee proposed a numerical method of predicting the behavior of concrete columns under biaxial loading. In this paper, to investigate the behavior of concrete columns under biaxial loading and verify the validity of proposed method, a series of test were carried out for sixteen tied reinforced columns with 100${\times}$100mm square and 200${\times}$100mm rectangular sections under various loading conditions. The length of columns was 1,300mm and the concrete strength was 28MPa. The boundary conditions at the both ends were hinged and end eccentricities were equal(400mm). Proposed numerical analyses applied to the test piece were performed to predict behavior of concrete columns with square and rectangular sections under various loading conditions. Test results were also compared with those using the moment magnifier method in ACI code. The test results showed that the moment magnifier method is conservative.

• 임상간호연구
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• 제21권2호
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• pp.143-153
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• 2015

Purpose: The purpose of this study was to develop a family-participated cardiac rehabilitation program and to test the effects of the program on self-efficacy, health behavior compliance, and family support for patients with percutaneous coronary intervention. Methods: The design of this study was a nonequivalent control group non-synchronize design. There were 30 participants in the experimental group and 29 in the control group. The program consisted of six consecutive cardiac rehabilitation education and counselling sessions for 5 weeks. Data were analyzed using $x^2-test$, Fisher's exact test, and t-test using the SPSS program. Results: Self-efficacy, health behavior compliance, and family support scores were significantly increased in the experimental group compared to those in the control group. Conclusion: These results suggest that this program may improve self-efficacy, health behavior compliance, and family support in patients with percutaneous coronary intervention. Therefore, this program in which family members were included in supporting patients' adherence to health behaviors is recommended for use in clinical fields for the cardiac rehabilitation.

• 한국의류학회지
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• 제11권3호
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• pp.67-77
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• 1987

The purposes of this study were to investigate the relationship between mothers and daughters in sex-role identity and yin-yang clothing behavior as well as the relationship between sex-role indentity and yin-yang clothing behavior Sex-role identy was measured by Bem Sex-Role Inventory (1974) modified and supplemented for this study. For the measurement of yin-yang clothing behavior, researcher developed a questionnaire. Data were collected from 422 women, both college women and her mothers. For the statistical analysis, frequency, distribution, t-test, one-way analysis of variance, Duncan's multiple range test, $x^2-test$, Pearson's correlation coefficients, analysis of covariance. multiple regression analysis were used. The results of this research can be summarized as follows: 1 There was significant difference in yin-yang clothing behavior according to home environmental variables such as family type, mother's employment. 2. There was not significant difference in mother's yin-yang clothing behavior according to mother's sex-role identity. But positive significant relationship was found between daughter's sex-role identity and daughter's yin-fang clothing behavior. 3. Mother's sex-role identity had influence on daughter's sex-role identity And mother's yin-yang clothing behavior had influence on daughter's yin-yang clothing behavior, too. 4. Mother's fin-yang clothing behavior and daughter's sex-role identity directly affected daughter's yin-yang clothing behavior, but mother's sex-role identity indirectly affected daughter's yin-yang clothing behavior.