• Journal of the Korea Concrete Institute
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• v.20 no.1
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• pp.109-116
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• 2008

This study was performed to get information of self-healing mechanism in cement system and the influence of waterproofing admixtures for concrete on self-healing property. For testing, cement paste specimens cured for 7, 14 and 28 days were prepared and crushed into plate-shape pieces. Screened specimens with thickness not more than 1mm were covered with wet rags and cured in a plastic container for 7 and 28 days. After stopping hydration process of the specimens by treatment with acetone, the surfaces of specimens have been contacted with wet rags were analyzed by XRD, DSC, SEM and EDX. The analysis results showed that cement paste has self-healing property and this property is mainly affected by water. Self-healing in cement system is more effective and faster at an early stage of hydration as there is enough content of unreacted cement to make an additional hydration in this period. The results of this study also showed that waterproofing admixtures for concrete have a considerable effect on self-healing of cement pastes; i.e., they improved self-healing effect of cement and, especially, the specimen using admixture C has shown a lot of needle-like or fibrous hydration products which are estimated as ettringite. It is supposed that these ettringite products are effective to enhance self-healing in cement system.

• The Journal of the Acoustical Society of Korea
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• v.30 no.1
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• pp.22-32
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• 2011

The present study examined the effects of the complexity of the 3D models on the results of acoustic simulation which is the predominant tool of the acoustical design of buildings. Also, the effects of the 3D model on the auralized sounds were investigated. In order to carry out the study, four 3D models with different levels of complexity were introduced for a real auditorium which have different numbers of surfaces in the persuit of the guidance of odeon room acoustic software. The set-up of models was also based on the level of transition order of the program. And the acoustic experiments were performed measuring room acoustic parameters including SPL, RT, C80, D50. Acoustic computer simulations were performed using four different models. Then, the results of the computer modeling were compared with the measured acoustical parameters. In addition, sound sources were recorded in the field and auralized sounds were made in convolution with the impulse source made from acoustic modeling. Then, subjective tests were undertaken using auralized sounds. As the results, it was found that the result of the acoustic simulation were closer to the real room acoustic properties when 3D model was more particularly made. For the subjective test, the listening materials were acknowledged as similar with the real sound source when more complex 3D model was used. Then, it could be concluded that the complexity of the 3D model affects the results of the acoustic modeling as well as subjective tests.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.1
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• pp.456-465
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• 2018

This study was conducted to investigate the relationships among self-efficacy, family support, and self-care performance of gastric cancer surgery patients. The study was conducted from 11 October to 15 November 2013. Data were collected by self-report questionnaires from 121 patients who were diagnosed with stomach cancer and had undergone surgery at D university hospital in B city and were in follow-up care for 3 months to 5 years after surgery. Data were analyzed using SPSS/PC WIN 18.0 to obtain the percentage, average, mean rating, and standard deviation. In addition, t-test, ANOVA, Scheffe's test, Pearson's correlation and stepwise multiple regression were conducted. The degree of self-care performance in research targets showed significant differences by sex (t=-2.25, ｐ=0.027), religion (F=3.67, ｐ=0.028) and profession (F=4.17, ｐ=0.008). Self-care performance was positively correlated (r=0.60, ｐ<0.001) with the degree of specific self-efficacy. There was a significant difference in self-care performance by specific self-efficacy, religion and gender. The total explanatory power was 37.9% and the explanatory power of the degree of specific self-efficacy (${\beta}=0.53$) was greater than that of other factors. Therefore, it is necessary to provide interventions that improve specific self-efficacy to help patients with gastric cancer patients conduct self-care performance, and practical measures should be made with respect to religion and gender.

• Journal of Korea Port Economic Association
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• v.28 no.2
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• pp.129-153
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• 2012

Even though logistics service outsourcing becomes widespread in manufacturing and service industries, logistics service providers encounter fierce competition and lower profit. Decreased profit has negative impact on service providers' competitiveness, which in turn threats successful relationship with shippers. In this paper, we investigate the factors which influence the performance of service providers. Factors related to service contract are examined and we test an effect of concreteness and fairness of service contract. PLS (Partial Least Square) modeling method is applied and validated using data from logistics service providing companies in Korea. In the model, service contract clauses are classified into two categories including cost and risk sharing terms. PLS analysis shows that partnership and performance of service relationship is improved when contract clauses are specified in detail. This study will contribute in providing an operational direction in effectively establishing a positive relationship between the logistics service provider and the shipper.

• Korean Journal of Cognitive Science
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• v.27 no.3
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• pp.377-406
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• 2016

Current lists of the Korean emotion words either do not consider word frequency, or only include emotion expression words such as 'joy' while disregarding emotion inducing words like 'heaven'. Also, none of the current lists contains the concreteness level of the emotional words. Therefore, the current study aimed to develop a new Korean affect word list that makes up such limitations of the current lists. To do so, in experiment 1, valence, arousal and concreteness ratings of the 450 Korean emotion expression nouns and emotion inducing nouns were surveyed with 399 participants. In addition, in experiment 2, an emotional stroop task was performed with the newly developed word list to test the usefulness of the list. The results showed clear patterns of the congruency effects between emotional words and emotion expressing faces. Increased response times and more errors were found when the emotion of the words and faces are non-matched, than when they were matched. The result suggested that the newly developed Korean affect word list can be effectively adapted to studies examining the influence of various aspects emotion.

• Journal of The Korean Association For Science Education
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• v.22 no.3
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• pp.571-585
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• 2002

This is one of the basic research for inspecting the possibility of the development of logical thinking capability to make possible formal thinking. The 5th grade students (n=306) in the elementary school were participated in this study. Performing the 6 variable-controlling activities in the 'Thinking Science' program for one semester, the SRT II test and the Variable-Controlling test were operated to examine the effects on the development of the variable-controlling ability by treatments, gender, and cognitive levels. Performing of the variable-controlling activities was highly successive on the development of students' variable-controlling ability. Although learning effect on the ability of identifying causal variable was moderate, the abilities of controlling experimental condition, measurement of variable, and identifying result variable were significantly developed. There was statistically significant difference by gender. Girls showed better performance all the time in both groups. Boys in the experimental group were getting better gradually, so the difference by gender was somewhat decreased. Examining the variable-controlling ability by cognitive levels, students in the experimental group show significant increase in all levels, especially the students in early, mid, and mature concrete level show substantial learning effects. The results of this study implied that the variable-controlling activities in the 'Thinking Science' could be effective for learning of variable-controlling and eventually for the development of logical thinking capability to make possible formal thinking.

• 재활복지
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• v.21 no.3
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• pp.187-207
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• 2017

The purpose of this study was to explore the characteristics of defining concrete and abstract nouns for the elderly. A total of 382 elderly participated in this study and they were classified into four age groups (i.e., over 55 to under 64, over 65 to under 74, over 75 to under 84, and over 85 year-old group). They performed the word definition task, composed of five concrete and five abstract nouns. The total scores and numbers and ratio of core/supplementary meanings were compared among four elderly groups. The frequency and ratio of error types were also examined. The results showed that all four groups had statistically significant differences in total scores, numbers and ratio of core and supplementary meaning of concrete noun definition task. In addition, abstract noun definition performances revealed group differences except the two groups (over 75 to under 84 and over 85-year-old group). The oldest group showed a sharp increase in error production. The highest ratio of error types were personal experience in over 55 to under 64-year-old group, and over 65 to under 74 year-old groups; and for the target word repetition in over 75 to under 84 year-old group; and no response in over 85 year-old group. In conclusion, both concrete and abstract word defining abilities had age-related deterioration. This decline results from impairment in spreading semantic knowledge within semantic network, which is vulnerable to aging. Characteristics of word definition for elderly can provide basic information to understand various neurolinguistic disorders associated with age.

• Proceedings of the Korean System Dynamics Society
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• 2006.11a
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• pp.13-27
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• 2006

갈수록 증가하는 불확실한 경영환경에 대응하기 위한 방안으로 실시간기업 (Real-Time Enterprise)이라는 개념이 대두되고 있지만, 현재 이를 구체적으로 실행 하기 위한 연구들이 미흡한 상황이다 이에 본 논문에서 가트너가 제시한 RTE 정의를 바탕으로 RTE 활동 및 구체화 방안을 살펴봄으로써 RTE의 주요성공요인 (Critical Success Factors)을 도출하는 연구를 수행하였다 RTE CSF를 도출함에 있어서 시스템 사고(System Thinking)를 통해 생성 된 인과지도를 이용하였다.

• Proceedings of the Korea Multimedia Society Conference
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• 2002.11b
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• pp.716-719
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• 2002

이 연구의 목적은 근래에 초등학교 수학과 교육과정의 도형영역에 새로이 도입된 '공간감각'을 기르기 위한 웹 코스웨어를 개발하여 단순히 교과서에만 제시된 구체물 조작만으로는 기르기 힘든 공간감각을 기르는데 있다. 개발된 코스웨어는 학습내용을 수준별로 구성하고 있어 바로 학습 현장에 투입하여 수준별 학습, 개별화 학습을 실현할 수 있도록 하였다. 또한 초등학교 저학년에게 구체물로서는 조작할 수 없는 것들을 다양한 애니메이션 기법을 통하여 직접 조작해 볼 수 있도록 하고, 재미있는 놀이를 학습에 적절히 활용함으로써 학습 흥미도를 높이고자 하였다.

• Journal of the Korean Geographical Society
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• v.35 no.2
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• pp.321-340
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• 2000

삶의 질을 구성하는 사회공간적 요소들은 현실 세계의 각 영역들, 즉 물질적, 생태적, 상징적 영역들에 상응하는 입지. 환경, 장소라는 3가지 개념들로 범주화될 수 있다. 이들은 삶의 질의 구체적 내용들, 즉 기본수요에의 접근, 생태적 안전의 보장, 그리고 공동체적 정체성의 확보와 관련된다. 본 논문은 이와 같이 ‘삶의 질’을 위한 공간을 3가지 영역으로 유형화하고, 이의 구체적 지표들을 설정하여, 대구시민들을 대상으로 설문조사한 결과를 분석하였다. 또한 본 논문은 이러한 3가지 사회공간적 요소들을 종합적으로 고려하는 공동체의 개념을 제시하고, 삶의 질을 고양시키기 위한 공동체적 생활정치를 강조한다.