• Journal of the Korea Convergence Society
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• v.10 no.10
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• pp.99-105
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• 2019

In this study, the flow analysis around vehicle was carried out on various kinds of roof box models installed at the roof of vehicle. Through the analysis of fluid flow and pressure, we investigated which model was more suitable for driving. The four types of models were designed with their respective shapes of models 1, ${\beta}$, ${\delta}$ and ${\gamma}$, and the driving speed of car was set as 20 m/s. It was confirmed that the pressure for model ${\beta}$ became greatest compared to other models. And model ${\delta}$ has the lowest pressure among all models of roof boxes by installing a canoe with the structure for cable type. As the design data with the durability of roof box obtained on the basis of this study result are utilized, the esthetic sense can be shown by being grafted onto the car body at real life.

• Proceedings of the Korea Multimedia Society Conference
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• 1998.04a
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• pp.423-431
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• 1998

이진값을 가지는 이진 시스템을 모델화하고 설계하여 구현할 수 있도록 Petri Net의 한 부류인 박스의 마크수가 최대 1인 안전(safe)한 확장된 마크흐름선도(EMFG : Extended Mark Flow Graph)를 재구성하였다. 레벨박스와 펄스박스 및 게이트박스를 하나의 박스로 통일하였으며, 보존아크를 제거하고 서로 상반되는 개념을 가지는 일반아크와 역아크만을 사용하였고, 특히 트랜지션의 출력아크로 새로이 역아크를 도입함으로써 EMFG의 표현을 명확하게 하였다. 또한 EMFG에서 자기루프를 정의하였다. 그리고 이진 시스템을 모델링한 EMFG를 실제회로로 구현하는 방법이 새로이 제시되었다.

• Journal of Digital Convergence
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• v.20 no.5
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• pp.211-220
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• 2022

This paper proposes a green closed-loop supply chain network (GCSN) for optimizing closed-loop supply chains. The GCSN focuses on the application of the recycling express box in logistics circulation, accelerates the standardization of logistics operations and the use of express packaging in e-commerce companies, and promotes the reduction and greening of recycling express box in the e-commerce industry. The GCSN is represented as a mathematical formulation and implemented using LINGO. Greening, environmental protection, and wisdom are the general trends for promoting the growth of the e-commerce industry. Meanwhile, the price of raw materials has increased owing to a shortage of resources, which emphasizes the need for e-commerce enterprises to develop green packaging. Therefore, this study considers the shared circular packaging launched by e-commerce enterprises as the research object, and integrates the problem of facility positioning and path planning in the logistics system. The conclusion summarizes the significance of this study.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2006.04a
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• pp.103-112
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• 2006

제지 기계의 습부 공정을 안정화시키고, 또한 종이의 지필도에 악영향을 끼치지 않으면서 종이의 기계방향 물성의 변이를 줄이기 위해서, 보류도와 지필도 공정을 동시에 제어하기 위한 제어전략들이 개발되었다. 보류도와 지필도에 미치는 주 변수들에 관한 연구를 양이온성팜(CPAM)/벤토나이트 보류제와 파일럿 제지 기계를 사용하여 수행하였다. 마이크로파티클 보류제 첨가량이 보류도와 지필도에 미치는 영향을 설명하기 위해서 deposition efficiency 모델과 bridging strength 모델을 개발하였다. 제지 기계 보류 공정의 동특성 모델을 질량수지분석을 사용해서 개발하였다. 지료화학 변수의 효과를 모델에 포함하기 위해서, 보류도를 작업조건들에 의존하는 변수로 모델에 포함시켰다. 또한 지필도의 실험적 모델을 개발하고 보류공정을 위한 동특성 모델들과 연계해서 지필도의 동특성을 모사하였다. 여러 제어 전략들이 시뮬레이션상에서 실험되어졌다. 평량과 종이의 회분율 대신에 종이내의 펄프 질량과 충전제 질량을 제어하면 decouper를 사용하지 않고도 두 제어 루프간 상호작용을 줄일 수 있음을 보였다. 지필도의 제어를 위해서, 헤드박스 펄프 농도제어와 폴리머유량과 벤토나이트 유량의 비율제어를 제안하였다. 지종 변경시 백수농도의 설정값을 계산하는 문제를 해결하였다. 또한, 평량, 회분율, 백수농도 및 헤드박스 펄프 농도의 다변수제어가 논의되었다.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.17 no.2
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• pp.151-160
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• 2004

In the present study, Loop scheme is applied to generate smooth surfaces. To be consistent with the limit points of target surface, the initial sampling points are properly rearranged. The pointwise errors of curvature and position in the sequence of subdivision process are evaluated in the Loop subdivision scheme. A first-order shear deformable Loop subdivision triangular element which can handle transverse shear deformation of moderately thick shell are developed. The developed element is more general than the previous one based on classical shell theory, since the new one includes the effect of transverse shear deformation and has standard six degrees of freedom per node. The quartic box spline function is used as interpolation basis function. Numerical examples for the benchmark static shell problems are analyzed to assess the performance of the developed subdivision shell element and locking trouble.

• Journal of Korean Tunnelling and Underground Space Association
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• v.20 no.5
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• pp.823-837
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• 2018

Congestion of the city with the rapid industrial development was accelerated to build complex social infrastructure. And numerous structures have been designed and constructed in accordance with these requirements. Recently, to solve complex urban traffic, many researches of large-diameter tunnel under construction downtown are in progress. The large-diameter tunnel has been developed with a versatile double-deck of deep depth tunnel. For the safe tunnel construction, ground reinforcement methods have been developed in the weakened pillar section like as junction of tunnel. This paper focuses on evaluation of the effects of new developed ground reinforcement methods in double-deck junction. The values of reinforcement determined from the existing and developed methods were compared to each other by numerical simulation.