• Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
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• 1993.07a
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• pp.166-174
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• 1993

본 연구에서는 자유수면과 성층효과를 고려한 3차원 연안해수유동 수치모형을 개발하였다. 수치모형은 수심방향에 대해서 정규화된 좌표(c-coordinate)를 사용하며, 시간적분방법으로는 반음해법(semi-implicit)을 사용하여 계산시간의 효율성을 도모하였으며, 모드분리개념을 도입하여 내역항(Internal mode)에 대해서는 양해법을 사용하였으며, 외역항(External mode)은 수평방향 운동방정식과 연속방정식의 차분식으로부터 얻은 Poisson형태의 타도형 차분방정식을 Point-SOR법에 의하여 해석하였다. (중략)

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2022.06a
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• pp.815-817
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• 2022

포인트 클라우드는 다수의 포인트로 구성된 3차원 미디어 콘텐츠로, 기존의 2차원 미디어에 비해 방대한 크기를 가진다. 이러한 포인트 클라우드 데이터를 효과적으로 소비하기 위해서는 포인트 클라우드 데이터를 압축하는 것이 필수적으로 요구된다. 이에 따라, 국제 표준화 기구 The Moving Picture Experts Group (MPEG)에서는 2차원 비디오 코덱 기반의 포인트 클라우드 압축 방안인 V-PCC 압축 방안과, V-PCC 비트스트림을 저장하고 전송하기 위한 ISOBMFF 캡슐화 방안에 대한 표준화가 진행되고 있다. V-PCC는 기존의 2차원 비디오 코덱을 이용하기 위해 3차원 포인트 클라우드 데이터를 투영하여 2차원 패치를 생성하고, 생성된 패치를 2차원 그리드에 배치하여 2차원 이미지를 생성한다. 이 때, 생성되는 2차원 이미지는 패치의 모양 차이와 인코딩의 효율성 때문에 Group of Picture(GOP)마다 다른 크기를 갖는다. 이러한 이미지 크기의 차이는 반복적인 디코더 초기화를 유발하여 송신기와 수신기 모두에 큰 부담을 발생시킨다. 이에 본 논문에서는 비트레이트와 메타데이터를 적응적으로 제어하여 V-PCC 비트스트림을 반복적인 디코더 초기화 없이 안정적으로 송수신 하기 위한 Global grid 기반 V-PCC 전송 방안을 제안한다.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.12 no.4
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• pp.629-638
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• 1999

본 연구에서는 고속철도에서 차량·교량 구조물의 상호작용을 가능한 정밀하게 취급할 수 있는 3차원 해석모형을 개발하였다. 경부고속철도 교량형식인 PSC 박스거더 교량을 40m 단순 와 25-40-25m 3경간 연속 에 대해 뼈대요소를 사용하여 3차원으로 모형 하였으며, 궤도의 불규칙성은 정상확률과정으로 가정하고, 지수 스펙트럼 밀도함수를 사용하여 궤도의 형상을 생성시켰다. 열차는 경부고속철도 차량 하중효과가 가장 큰 동력차 만을 대상으로 17 자유도 모형과 38 자유도 모형으로 분리하여 개발하였다. 다양한 조건에 대한 분석결과를 검토하면 여러 가지 상황에서 38 자유도 모형의 필수 성이 보여지고 있다. 특히 교량의 솟음 및 장기 처짐에 의한 궤도형상변화가 있는 경우에는 반드시 38 자유도 모형이 적용되어야 하는 것으로 분석되었다. 또한 제동하중이 작용할 때 쏠림 효과에 의한 영향이 큰 것으로 평가되어, 제동에 의한 교량의 동적 거동은 종변 위에 대한 자유 도를 고려할 수 있는 주행차량모형으로 해석되어야 함이 규명되었다.

• Plant Journal
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• v.8 no.3
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• pp.55-63
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• 2012

This study aims to suggest the improved business process by analyzing the current design process on work flow of the 3D design of power plant, drawing a problems and setting the improving direction through the integration method of the business process reengineering(BPR). In order to realize the improved business process, the integrated design performance system focused on the 3D design was established and accordingly the study analyzed cases of project performances through the integration system and drew the improved effects quantitatively. In the result of the project performance applied with the 3D design integration system, it showed 20.4% design cost saving effect for appropriate rated cost and the integration of design information from each design parts, sub contracters and vendors reduced overlapped works and improved the consistency of repeated design alteration.

• Journal of Information Technology Application
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• v.3 no.2
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• pp.25-48
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• 2001

This Study intends to Investigate the economic impact of information technology investment. Six countries in OECD are selected and analyzed to understand the empirical relationship between informatization level and productivity Correlation test and regression analysis are executed, using macro data concerning informatization index, total factor productivity and real output per worker hour The impact of informatization level on productivity is characterized by the time lag effect which is used to explain the productivity paradox in precedent studies. Empirical analysis shows that the higher informatization level and information intensity, the lower time lag effect. The result indicates that IT investment has characteristic as sunk cost and the economic impact is appeared after a certain period of time.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.6
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• pp.4098-4107
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• 2015

The purpose of this study was to investigate the effects of 8-week schroth 3-dimensional exercise and ball-sling complex exercise treatment on cobb's angle, abdominal muscle endurance, flexibility and balance in adolescents with idiopathic scoliosis. Thirty subjects with scoliosis were random assignment into one of two experimental groups, either schroth treatment(n=15) or ball-sling complex exercise treatment(n=15). Exercise program was to perform for 8-week and 90min and 3 times per week. The results of this study were as follows; First, cobb's angle was significantly decreased after 8-weeks in schroth treatment(p<.001). And also abdominal muscle endurance(p<.05), flexibility(p<.001) and balance(p<.001) were significantly improve in pre vs. post treatment. Second, the ratio of cobb's angle change was significantly higher in schroth treatment compared to ball-sling complex exercise treatment following 8-weeks(p<.05). These results suggest that although both the schroth treatment and bal-sling complex exercise treatment in adolescents with idiopathic scoliosis can improve on cobb's angle, abdominal muscle endurance, flexibility and balance, but schroth treatment was better than ball-sling complex exercise treatment improving effect of cobb's angle. Therefore, we consider that schroth treatment has more effect of prevention and therapy in idiopathic scoliosis in adolescents.

• The Journal of the Korea Contents Association
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• v.20 no.12
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• pp.123-135
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• 2020

This study examined how the quality of Netflix service affects user satisfaction and continuance intention. This study classified the quality of Netflix service as content diversity, rate system appropriateness, recommendation system, N-screen service, binge viewing, and service quality, and examined the effect of each dimension on user satisfaction and continuous intention. We conduced an online survey on 202 Netflix users and analyzed the data with the SEM. Results are as follows. First, content diversity, recommendation system, binge-viewing and service quality are positively associated with user satisfaction. Second, the N-Screen service has neither direct nor indirect effects on continuance intention. However, rate system has a direct effect on continuance intention. On the other hand, content diversity, recommendation systems, binge-viewing, and quality of service affect continuance intention positively through user satisfaction. Finally, it is shown that user satisfaction and continuance intention have a significant static correlation as predicted.

• Journal of Korean Elementary Science Education
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• v.43 no.2
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• pp.337-352
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• 2024

This study develops an informal science education program based on a creative design for the promotion of participation and action and explores the validity and effectiveness of the program. The program consists of three mini-projects, namely, The Martian: Surviving from the Mars, So Good to Have Seonjeongneung, and Designing a Sunshine Restaurant, with distinct topics focusing on the localization and contextualization of the region in which the program was implemented to encourage students' participation and action. The researchers selected three topics for each mini-project through discussions and revisions. The program is designed for 42 lessons across the three mini-projects and offers a presentation session in which students present their learnings from the program, constructed to facilitate personal contextualization. Participants included 15 elementary school students from Grades 5 and 6 who took surveys before and after the program. The pre-post surveys comprised two dimensions, 'Participation and Action' and 'Positive Experience about Science,' to examine the effectiveness of the program. At the end of the survey, we added a self-descriptive question that allows students to freely write down their feelings and thoughts. We checked the students' thoughts. The effectiveness of the program was illustrated by the largest increase in the "safe society" category, whereas there was little increase in other categories under the 'participation and Action' dimension in the Korean Science Education Standards. 'Science-related Self-concept' exhibited the largest increase, whereas the other categories displayed little increase from the 'Positive Experience about Science' dimension category.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2017.05a
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• pp.243-245
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• 2017

In the face recognition technology, which has been studied a lot, the security of the face recognition technology is improved by receiving the depth data as a weak point for the 2D. In this paper, we expect the effect of cost reduction by enhancing the security of 2D by taking new features of eye flicker that each person possesses as new data information.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2011.04a
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• pp.261-264
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• 2011

유한 요소 기법을 이용한 허니콤 구조물의 해석은 모델링 작업 및 격자 생성의 어려움뿐만 아니라 과도한 해석 시간이 요구되기 때문에 균질화 기법은 계산상의 효율성을 증대시킬 수 있는 매우 유용한 방법이라 할 수 있다. 그러나 나노 크기의 구조물에서는 표면 효과로 인하여 거시적인 구조물에서와는 매우 상이한 기계적 거동 양상을 띠게 되며 균질화 기법을 나노 크기의 허니콤 구조물에 적용하기 위해서는 이러한 표면 효과를 반영해야만 한다. 본 논문에서는 표면 효과를 고려한 유한 요소를 제안하고 이를 이용하여 나노 크기의 3차원 허니콤 구조물을 균질화 기법을 이용하여 등가의 2차원 판으로 대체하였다.