• Magazine of the Korea Concrete Institute
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• v.5 no.3
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• pp.125-132
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• 1993

콘크리트의 인성개선을 위하여 횡보강근을 사용할 수 있으나 보통강도으 철근ㅇ르 사용하였을 경우에는 조속한 철근의 강상으로 인한 콘크리트으 인성개선효과가 급격히 떨어지기 때문에 고강도 횡보강도에 의한 압축인성 개선효과를 이론 및 실험으로 고찰하였다. 실험결과 각 공시체의 변형능력을 비교해 보면 보통강도근의 경우 콘크리트 응력블록계수가 최대일 때 콘크리트의 압축단 변형도가 1%내외인데 비하여 고강도근으로 횡보강하였을 경우가 콘크리트의 압축변형도는 2%로서 충분한 휨압축 인성개선용으로 콘크리트의 충분한 인성개선이 가능하다고 볼 수 있다.

• The Journal of the Korea Contents Association
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• v.12 no.7
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• pp.497-509
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• 2012

The purposed of this study was to evaluate the effects of psycho-social maturity personality improvement program for university students. This program based on the book written by Lee et al.(2010) to improve the personality for university student was used. The program consisted of a total of 13 session and every session consisted of a 50 minutes lecture and 100minutes activity program. The researcher carried out the pre-test, post test and follow up test regarding psycho-social maturity and conducted Mann-Whitney U test and the ancova. The results showed who had participated in counseling groups reported significant improvement of psycho-social maturity total scores and sub scores, while the control group did not report any significant improvements. After 10 weeks follow-up point, these changes experienced by the experiment group on the improvement of the psycho-social maturity. Finally the personality program helped improve the psycho-social maturity.

• Journal of Digital Convergence
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• v.14 no.9
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• pp.43-51
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• 2016

The purpose of this study is to find out what are the factors that influence christian characteristics among christian theology major and non major students. Among the diversity factors, especially focused on studies of faith character variable and satisfaction of chapel, and how much these factors affect and how it correlates and what affects the most between christian theology major and non major students. This study has been surveyed to students who are enrolled in B University. As a result, christian theology major students have larger portion of Christian characteristics than non major students. Additionally students who are satisfied with chapel, having personal prayer time, meditation time, spending longer hour with bible and involving church activities have highly established christian personalities upon students.

• Journal of the Korean Society for Nondestructive Testing
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• v.20 no.5
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• pp.424-430
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• 2000

In order to develop an ultrasonic evaluation method for properties degradation of high temperature materials, a number of Cr-Mo-V steel samples were heat-treated and their damage mechanism was examined. Ultrasonic parameters such as velocity, attenuation, and more recently developed nonlinear acoustic parameter were measured. The nonlinear acoustic parameter was found to be most sensitive to material degradation mainly attributed to the precipitation of impurities in grain boundaries. When compared to the electrical resistivity results, the nonlinear parameters showed similar behavior. There existed a relatively good correlation between the nonlinear parameter and the fracture appearance transition temperature (FATT) obtained by Charpy V-notch impact test. Based on the relationship between the FATT and the fracture toughness ($K_{IC}$), correlation between the nonlinear parameter and $K_{IC}$ was established.

• Journal of Digital Convergence
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• v.14 no.7
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• pp.37-43
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• 2016

This study is based on finding out how christian characteristics affects between christian theology major and non major students upon factors. Among various impacts, we especially have focused on personal profile and college life satisfaction, and what factors could relate to christian characteristics between personal characteristics variable (gender, age, grade, group activities, religion, communication time with parents, interpersonal relationship, ect.) and college satisfaction. Also, this study focused on what could be the differences between the christian theology major and non major students and if there are the differences, the survey will be analyzed and researched to figure out how much it differs from each other. Through this study christian theology major have presented the right christian virtue and had more effects of christian world view than non christian theology major students.

• Journal of the Korean Society for Nondestructive Testing
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• v.18 no.1
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• pp.10-16
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• 1998

Remaining life of turbine rotors with a crack can be assessed by the fracture toughness of the aged rotors at service temperature. DC potential drop measurement system was constructed in order to evaluate material toughness nondestructively. Test material was 1Cr-1Mo-0.25V steel used widely for turbine rotor material. Seven kinds of specimen with different degradation levels were prepared according to isothermal aging heat treatment at $630^{\circ}C$. Electrical resistivity of test material was measured at room temperature. It was observed that material toughness and electrical resistivity decreased with the increase of degradation. The relationship between fracture toughness and electrical resistivity was investigated. Fracture toughness of a test material may be determined nondestructively by electrical resistivity.

• Journal of the Korea Institute of Building Construction
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• v.17 no.5
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• pp.403-409
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• 2017

In this study, mix proportioning of porous concrete with compressive strength and porosity exceeding 3MPa and 30%, respectively, was examined and then load capacity and flexural toughness of the porous concrete block were evaluated according to the different arrangements of the GFRP bars. To achieve the designed requirements of porous concrete, it can be recommended that water-to-cement ratio and cement-to-coarse aggregate ratio are 25% and 20%, respectively, under the aggregate particle distribution of 15~20mm. The failure mode of porous concrete blocks reinforced with GFRP bars was governed by shear cracks. As a result, very few flexural resistance of the GFRP was expected. However, the enhanced shear strength of porous concrete due to the dowel action of the GFRP bars increased the load capacity and toughness of the blocks. The porous concrete blocks reinforced with one GFRP bar at each compressive and tensile regions had 2.1 times higher load capacity than the companion non-reinforced block and exhibited a high ductile behavior with the ultimate toughness index ($I_{30}$) of 43.4.

• Journal of the Korean Society for Nondestructive Testing
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• v.17 no.2
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• pp.81-88
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• 1997

Impact behavior of carbon fiber reinforced plastics (CFRP) laminates were evaluated with tension test and compact tension test. A steel ball launched by an air gun collides against CFRP laminates to generate impact damage of relatively low energy. The static tensile and fracture toughness tests were performed to evaluate the residual strength and the AE behavior of impact-damaged laminates. As a results, it was found that the static strength, the fracture toughness and the AE-event count were decreased with increasing of impact velocity and delamination area, and to have a different strength ratio and fracture toughness ratio for each stacking method. And also, it was confirmed that strength and fracture toughness of impact-damaged CFRP laminates could be evaluated and analyzed quantitatively by AE techniques.

• The Journal of the Korea Contents Association
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• v.17 no.2
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• pp.26-37
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• 2017

This study aims to theoretically and empirically establish the characteristics and component factors of creativity character of college students. Putting together preceding researches related to the concept and structure of creativity character through the theoretical approach, the in-depth interview and open survey were conducted targeting 70 specialists in education, education engineering, consultation meeting, and researchers' meeting about creativity character of college students. In the results, as creativity character for college students, creativity was classified into cognitive creativity and affective creativity while character was classified into moral character, social character, and emotional character. Especially, the creativity character of college students emphasized the importance of character more than creativity. Through such results, it aims to suggest a new perspective on creativity character of college students, and moreover to provide basic data to set up the research direction to develop a tool to measure creativity character of college students for follow-up researches. Also, it is considered to establish the theoretical, empirical foundation contributing to the establishment of teaching-learning method and education engineering qualitatively enhanced in the site of college.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2011.04a
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• pp.476-479
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• 2011

티타늄 합금은 높은 내부식성, 우수한 피로 수명과 무게비에 비해 높은 강도를 가진다는 우수성으로 인해 항공기 부품과 화학 공업 분야등에 다양하게 사용되고 있다. 이번 연구에서는 Ti-3Al-2.5V 합금 TIG 용접부에 대하여 용접부 인성과 기계적 성질에 영향을 주는 가장 중요한 인자인 용접 입열에 대한 영향을 평가하고자 하였다. 이에 입열조건에 대한 용접부에 대한 강도, 충격 인성과 노치 인성을 평가하였으며 적정 입열 조건에서 강도와 인성이 우수한 용접부를 얻을 수 있다는 것을 확인하였다.