• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2001년도 봄 학술발표회 논문집
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• pp.629-634
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• 2001

This study is to characterize the material property of early age high performance concrete emphasizing compressive strength using nondestructive testing methods. Three high performance concrete slabs of 600, 850 and 1100kg/$cm^{2}$ compressive strengths were prepared together with cylinders from same batches. Cylinder tests were peformed at the ages of 7, 14, 21 and 28 days after pouring. Using the impact echo method, the compression wave velocities were obtained based on different high performance concrete ages and compressive strengths. The equation to obtain the compressive strengths of high performance concrete has been developed using the obtained compression wave velocities. Using the SASW (spectral analysis of surface wave) method, the equation have also been developed to obtain the compressive strengths of high performance concrete based on the surface wave velocities.

• 지역사회간호학회지
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• 제27권4호
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• pp.299-308
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• 2016

Purpose: The purpose of this study was to develop a positive psychology-based and character strengths-integrated activity program for elders living alone in rural areas, and then to examine the effectiveness of the program. Methods: A quasi-experimental pre- and post-test design with a nonequivalent control group was used. The participants included 59 elders in total, of whom 30 were assigned to the experimental group and 29 to the control group. positive psychology-based and character strengths-integrated activity program for elders consists of sixty-minute sessions held twice per week during 6 weeks, hence 12 sessions in total. Results: There were significant differences between the experimental and control groups in depression, vitality and life satisfaction (all p<.001). Conclusion: The positive psychology-based and character strengths-integrated activity program for elders living alone in rural areas is effective in that it decreased the degree of depression and increased the vitality and life satisfaction in the participants.

• 한국구조물진단유지관리공학회 논문집
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• 제22권2호
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• pp.98-104
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• 2018

콘크리트 비파괴강도 추정식은 일반적으로 콘크리트 강도를 결정하는데 사용된다. 그러나 기존의 추정식들은 대부분 제한된 실험 변수를 토대로 제안되어 배합조건, 강도특성 등이 다양한 실제 공용중 교량의콘크리트 압축강도 추정시 많은 오류를 포함한다. 본 연구에서는 297개 공용 교량의 정밀안전진단 결과 중 콘크리트 비파괴시험 및 현장 코어강도 시험결과를 토대로 콘크리트 부재의 코어강도와 비파괴 추정강도 평가결과를 비교분석하였다. 분석결과 분석이 이루어진 기존 추정식들 중 일본건축학회 CNDT소위원회 강도계산식이 다른 추정식에 비하여 실제파괴강도와의 오차가 가장적고 상관분석의 신뢰도도 가장높은 것으로 검토되었다. 그러나 이 추정식은 코어강도가 30 MPa이상일때 추정강도는 과소평가되는 것으로 나타났다. 이에 본 논문에서는 추정식에 의한 강도와 현장 코어강도사이의 관계를 활용하여 회귀분석을 통한 개선된 비파괴강도 추정식을 제안하였다.

• Computers and Concrete
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• 제20권2호
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• pp.247-255
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• 2017

This study aimed to develop a Rule Based Mamdani Type Fuzzy Logic (RBMFL) model to predict the flexural strengths and compressive strengths of blended cements under elevated temperatures. Clinoptilolite was used as cement substitution material in the experimental stage. Substitution ratios in the cement mortar mix designs were selected as 0% (reference), 5%, 10%, 15% and 20%. The data used in the modeling process were obtained experimentally, after mortar specimens having reached the age of 90 days and exposed to $300^{\circ}C$, $400^{\circ}C$, $500^{\circ}C$ temperatures for 3 hours. In the RBMFL model, temperature ($C^{\circ}$) and substitution ratio of clinoptilolite (%) were inputs while the compressive strengths and flexural strengths of mortars were outputs. Results were compared by using some statistical methods. Statistical comparison results showed that rule based Mamdani type fuzzy logic can be an alternative approach for the evaluation of the mechanical properties of concrete under elevated temperature.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1990년도 봄 학술발표회 논문집
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• pp.90-95
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• 1990

It is widely recognized that the strengths of reinforced concrete members have random characteristics due to the variability of the mechanical properties of concrete and steel, the dimensional error as well as incorrect placement of reinforcing bars. Statistical models of the variabilities of strengths of reinforced concrete members, therefore, need to be developed to evaluate the safety level implied in current practices. Based on the probabilistic models of basic factors affecting the R.C. member strengths, in this study, the probabilistic characteristics of member resistance have been studied through Monte Carlo simulation.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2002년도 봄 학술발표회 논문집
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• pp.285-290
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• 2002

The double composite box girder is a structural system filled with concrete at the bottom of the steel box in the negative moment region increasing the flexural strengths. Flexural strengths of the double composite steel box girders are investigated through a series of the experimental tests and the numerical analysis. The experimental tests are performed on the three kinds of steel box girders with the different concrete depths including loom, 15cm, and 20cm. Moment-curvature relations are calculated based on the sectional analysis method describing the nonlinear natures of concrete and steel. In the finite element analysis the nonlinear nature of concrete is described based on the three dimensional four-parameter constitutive model recently developed and that of steel is described based on von Mises failure criterion. The ultimate flexural capacities of the box girders predicted using sectional analysis and finite element analysis show good agreement with those of the experiments.

• 가정과삶의질연구
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• 제32권6호
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• pp.19-30
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• 2014

The purpose of this study was to identify the relationships between Healthy Family Support Center (HFSC) program participation and family strengths and program needs based on HFSC participants' individual, family, and community characteristics. A total of 695 HFSC participants who were married and had participated in HFSC programs were recruited through 25 local HFSCs in Seoul. A multiple regression method was conducted for data analysis. The major findings are as follows. Family strengths was related to the variables of age, education, monthly household income, and participation in family counseling and sharing family care programs. In terms of program needs, the variables of marital conflict, difficulty in care, financial distress, family strengths, and family-friendly community were associated with HFSC program needs while participants' socio-demographic characteristics were not related to program needs. This study highlights that HFSC programs have different target populations considering that the level of family strengths was different among the various programs' participants. In addition, program needs are different depending upon the HFSC participants' experiences in the family and community. These findings suggest that it is important to consider participants' family and community characteristics as well as participants' socio-demographic characteristics to provide appropriate programs for all HFSC participants.

• 한국가족관계학회지
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• 제22권3호
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• pp.3-27
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• 2017

Objectives: This study examined the effects of married couple's sexual satisfaction on perceived family strengths based on family systems theory that the changes of family subsystem could extend itself to involve the entire family system. Methods: For this purpose, the structured survey was conducted by 151 married couples living in Jeollanam-do and Gwangju. The data was analysed by SPSS 21.0 program. Results: First, the average scores of family strengths and sexual satisfaction were a little higher than the middle. There were no differences between husbands and wives. Second, family strengths perceived by husbands were significantly affected by income satisfaction, conflicts and sexual satisfaction. In wives, education level, satisfaction with communication times, conflicts and sexual satisfaction were influential factors. Conclusion: It is necessary to pay the most attention to sexual satisfaction of couples in order to improve family strengths. In addition, it is actually required to develop various couple programs about enhancing sexual satisfaction related to the effective couple communication and problem-solving methods. It also have to imply the requirements considering characteristics of male and female, husbands and wives.

• 대한불안의학회지
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• 제12권1호
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• pp.13-20
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• 2016

Objective : The purpose of this study was to verify the differences of expressed character strengths graded as per the Korean Strength Scale, based on the type of work. Methods : A total of 2,444 conglomerate workers were classified into two groups: 1,356 office workers and 1,088 production workers. The subjects were examined through a web or mobile application based on the Korean Strength Scale. The Korean Strength Scale consists of a total of four top entries and 25 sub-items with appropriate validity. Results : The difference in the average score of sum of character strengths between the two groups was not significant. In the office worker group, character strengths such as love of learning, creativity, perspective, curiosity, facilitation, judgment and faith had significantly high scores. On the other hands, modesty, hope, gratitude, sincerity, magnanimity and self-regulation were high in the production worker group. The results remained unchanged in additional analysis of covariants as sex, age and education level, except for self-regulation and faith. Conclusion : Our results suggest significant differences in the character strengths between the two types of work; however, the average of sum of character strength score remains unchanged. These results may help to understand differences between work environments and thus help to establish a positive foundation.

• 디지털콘텐츠학회 논문지
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• 제15권2호
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• pp.155-165
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• 2014

본 연구는 기업의 경영자 교육 효율 재고를 위해 학습태도 모형을 실증하는 연구이다. 이를 위해 연구자는 긍정심리학을 기반으로 분류된 학습자의 성격강점과 학습 친화력 강화와 학습태도 개선의 인과 관계를 검증하였다. 최근 기업들은 온 오프라인 경영자 재교육을 통해 기업의 생산성을 높이려고 시도하고 있다. 연구자는 디자인과 경영분야 교과목을 접목하여 학습태도에 미치는 영향요인을 확인하고, 경영자 교육에 함의를 논의하고자 하였다. 분석결과에 따르면, 첫째, 온라인과 오프라인 수업은 공히 학습자 성격강점이 친화력강화에 정(+)의 영향을 미치는 것으로 확인되었다. 둘째, 친화력강화도 온라인과 오프라인 수업학습태도 개선에 정(+)의 영향을 미치는 것으로 확인되었다. 셋째, 온라인과 오프라인 수업은 모두 학습자 성격강점이 학습태도 개선에 직접적으로 유의미한 영향을 주지 못하였으며, 따라서 친화력 강화 변인이 매개변수 역할을 함을 확인할 수 있었다.