• Journal of Dental Rehabilitation and Applied Science
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• v.29 no.3
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• pp.209-223
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• 2013

This study was to evaluate the stress distributions of prefabricated, customized abutments and fixtures according to their material and shape by three-dimensional finite element analysis. And to investigate the fatigue life and fracture characteristics. Mandibular models were fabricated by reconstruction of the CT scan of patients with normal occlusion. A total of six finite element models were designed, a load of 100 N was applied on the buccal cusps vertically, and 30 degree obliquely. 10 specimens each were fabricated for the more clinically widely used 4 type abutments and were loaded according to ISO 14801. Differences in stress distribution patterns were not found according to the materials of the abutments and fixtures. But a slight difference in the stress level was detected. Customized abutment groups showed lower crown stress levels. One-piece zirconia implant showed the lowest bone stress levels. In the fatigue test, highest values were measured in group 7. Prefabricated abutments showed less variation of fatigue life (P<0.05). Use of customized abutments can improve the fracture resistance of restorations. Especially, use of customized zirconia abutments reinforced by titanium screw connecting parts is recommended.

• The Journal of Korean Academy of Prosthodontics
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• v.55 no.2
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• pp.151-155
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• 2017

Purpose: The aim of this study was to evaluate screw removal torque of the two-piece zirconia abutment with the novel titanium component compared to the conventional one-piece titanium abutment in the internal connection implant before and after dynamic cyclic loading. Materials and methods: Two types of the abutment assemblies with internal connection were prepared and divided into the groups; titanium abutment-titanium abutment screw assemblies as control, and zirconia abutment-titanium socket-titanium abutment screw assemblies as experimental group. A total of 12 abutments and implants were used of six assemblies each group. Each assembly was tightened to 30 Ncm. A cyclic load of 300 N at an angle of 30 degrees in reference to the loading axis was applied until one million cycles or failure. The removal torque values (RTVs) of the abutment screws were measured with a digital torque gauge before and after cyclic loading. The RTVs of the pre load and post load were analyzed with t-test, and P-values < .05 were considered statistically significant. Results: The assemblies of both groups survived all after the dynamic cyclic loading test without screw loosening. The statistically significant differences were found between the mean RTVs before and after the cyclic loading in both groups (P < .05). The RTV differences for the control and the experimental group were $-7.25{\pm}1.50Ncm$ and $-7.33{\pm}0.93Ncm$, respectively. Statistical analysis revealed that the RTV differences in both groups were not significantly different from each other (P > .05). Conclusion: Within the limitation of this study, the two-piece zirconia abutment with the titanium component did not show a significant RTV difference of the abutment screw compared to the titanium abutment after dynamic cyclic loading.

• Management & Information Systems Review
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• v.32 no.4
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• pp.81-101
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• 2013

The purpose of this study was to examine the effects of mental similarity and internal locus of control, which are the characteristics of an organizational member, and individualism and power distance, which are an individual's sense of value, on mentoring function in an informal mentoring relationship of ROK army. For corroborative analysis, the sample was collected from 547 questionnaires, which contain validate data out of 1,000 questionnaires distributed to junior officers working at ROK army's division level unit. The data proved that, First, mental similarity and internal locus of control positively effected upon mentoring function. Second, individualism positively effected upon mentoring function while power distance had a negative effect on it. Thus in an informal mentoring relationship of ROK army, a mentee perceived as he or she gains more support from mentoring function when a mentee recognizes higher mental similarity, individualism, and is in an internal locus of control. On the other hand, a mentee who perceived higher power distance felt as he or she gets less support from mentoring function. Through this investigation, the significance of influential components of mentoring function in a mentoring relationship of ROK army was demonstrated, and these research results could be highly supportive for a future research based on mentoring relationship.

• Journal of Educational Research in Mathematics
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• v.18 no.2
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• pp.201-221
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• 2008

This study discusses how the humanity mathematics education can be realized in practice. The essence of mathematical concept is gradually disclosed revealing the ambiguities in the concept currently accepted and clarifying them. Historical development of mathematical concepts has progressed as such, exemplified with the group-theoretical thought and continuous function. In learning of mathematical concepts, thus, students have to recognize, reveal and clarify the ambiguities that intuitive and context-dependent definitions in school mathematics have. We present the process of improvement of definitions of a tangent and a polygon in school mathematics as examples. In the process, students may recognize the limitations of their thoughts and reform them with feelings of humility and satisfaction. Therefore this learning process would contribute to cultivating students' minds as the humanity mathematics education pursues.

• Defense and Technology
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• no.5 s.243
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• pp.18-29
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• 1999

$C^4I$ 체계는 나토군의 효과적인 지휘통제로 정보수집/전파, 지휘결심, 타격명령/실시 등의 제반 절차가 실시간에 이루어지게 되므로 반응시간의 단축을 이루었으며, 정밀유도 무기체계의 유고 핵심시설에 대한 집중 타격은 유고의 군사력을 거의 초토화시킨 상태이다. 코소보 사태와 관련하여 나토군이 선보인 첨단 무기체계 및 신기술은 우리의 국방과학기술의 현주소를 깨닫고 시금석으로 삼을 수 있는 좋은 계기임에 틀림없다. 지금 우리는 기술패권주의 시대에 살고 있고, 이러한 시대에 살아남기 위해서 무엇보다 필요한 것은 최첨단 국방과학기술의 개발일 것이다

• Korean Journal of Cognitive Science
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• v.25 no.1
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• pp.25-49
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• 2014

Advertisement for one type of product competes against another type using different advertising strategies. It is important to know which factors influence people's perception of the message within the advertisement and their formation of attitudes towards the advertisement. Using multidimensional scaling, this study investigated what main factors were important when people perceive beverage advertisements on TV. A positioning map was constructed based on similarity ratings of 14 drink advertisements. We examined the meaning of the three dimensions of the positioning map by asking a different group of participants to rate on components of attention, attitudes toward advertisements and products, and intention to purchase the product in each advertisement. It was found that three dimensions in the map was attention to content, color, and motion respectively. More importantly, the attentional component to content was related to the attitude of affection and action toward a beverage introduced in advertisement. These results suggest that content-based attention in advertisements induces a positive attitude toward the advertisements.

• Journal of the Korea Convergence Society
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• v.9 no.3
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• pp.79-90
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• 2018

The purpose of this study was to investigate the difference of individuals with social anxiety tendency and normal people according to existence of emotional context in attention processing for positive facial stimulation. To do this, we investigated attentional processing for positive face stimuli in a condition without/with emotional context. SADS and CES-D were administered to 800 undergraduate students in D city and the social anxiety group (SA, n=24) and the normal control group (NC, n=24) were selected. In order to measure the two factors of attention process (attention engagement and attention disengagement), first gaze direction and first gaze time were measured through eye-movement tracking. The results show that the SA group exhibited faster attention disengagement from positive face stimuli compared to the NC group in the condition without context. But, when the positive context presented with positive face stimuli, there is no difference between SA and NC. This result suggests that the positive background affects emotional processing of social anxiety disorder.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.4 no.1
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• pp.114-123
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• 1993

The authors applied Toddler Temperament Scale(TTS) to ADHD patient group, other disease group and normal control group to elucidate temperamental characteristics of ADHD patients in their toddler stage. 1) ADHD group showed significant difference from the control group in 'activity', 'rhythmicity', 'approach', 'adaptability', 'intensity', 'persistence' and 'threshold' categories. 2) ADHD group and other disease showed significant difference from the control group in 'adaptability' and 'persistence' categories. 3) ADHD group was significantly different from other disease group or control group in 'activity' and 'approach' categories. 4) In total scores of TTS, ADHD group and other diease group showed significant difference from control group. 5) Classification ratio of TTS for ADHD by discriminant analysis was 84.3%. Above results suggest that the ADHD patients may reveal characteristic traits in their toddler stage Further research should be focused on the development and refinement of assessment tools for the early detection and prevention for ADHD.

• Proceedings of the Korea Contents Association Conference
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• 2018.05a
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• pp.415-416
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• 2018

육군은 국민들이 육군의 정책을 흥미 있으면서도 쉽게 이해할 수 있도록 유머 기법을 적용한 사진영상 홍보콘텐츠를 온라인 홍보에 적극 활용하고 있다. 본 연구에서는 유머가 육군에 관한 메시지 전달 기법으로 유용한지를 정교화 가능성 모델을 바탕으로 고 저유머 홍보 동영상을 고 저관여 집단에게 보여준 후 인지 정서적 요소(주의-기분-신뢰)와 태도에 어떻게 영향을 미치는지 살펴보았다. 그 결과 유머는 육군 홍보에 긍정적 요소로 작용하며, 주의와 기분 요소를 증가시키는데 기여하고, 이러한 주의와 기분 요소는 태도 형성에 상관관계가 있고 영향력이 높은 것으로 나타났다.

• Journal of the Korean Institute of Landscape Architecture
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• v.49 no.5
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• pp.97-111
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• 2021

The purpose of this study was to analyze commemoration characteristics of the United States of America, the Commonwealth, and Germany through representative 14 military cemeteries of World war II in Western Europe. Based on the commemoration characteristics such as spacial characteristic, commemorative elements, and graves and headstone, the commemoration culture among U.S., the Commonwealth. and Germany were studied comparatively. The results are as follows. First, taking geometrical form with mainly square type, rarely circle and spiral patterned, most cemeteries were structured spatial central axis with symmetry, those cemeteries were styled neoclassical, but some of the U.S. cemeteries were modernistic, connecting spaces organically with curved line layout. Second, chapel, the wall of missing, the wall of battle map, and sculpture in the U.S military cemeteries, and 'the cross of sacrifice' and 'the stone of remembrance' as classical monument in the Commonwealth war cemeteries were commonly applied standardized commemorative elements, but commemorative monuments in German military cemeteries were restricted except monumental cross. Third, the symbolic cross of christianism was used all cemeteries to console and cherish the soul of soldiers, specially the Latin crosses in the U.S military cemeteries delivered political message as the american martyr for Western Europe and also the power of the U.S., but the cross in German and the Commonwealth war cemeteries were basically cherish and comfort individual spirit. Fourth, showing the power of victory with national patriotism, the U.S. strongly represented christianism and liberal democracy against communism, the Commonwealth showed imperialistic style, and German military cemeteries were quietly appeared as traditional style forwarding reconciliation and peace. This study suggest the war cemeteries have national identity with typical form and symbolic aesthetics. Further study will be required to materialize sublime commemoration in national cemeteries and to form advanced commemorative culture in Korea.