• Korean Journal of Heritage: History & Science
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• v.14
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• pp.197-224
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• 1981

• Korean Journal of Heritage: History & Science
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• v.27
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• pp.83-100
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• 1994

• The monthly packaging world
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• s.344
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• pp.56-60
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• 2021

• The monthly packaging world
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• s.324
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• pp.48-52
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• 2020

• Korean Journal of Heritage: History & Science
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• v.11
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• pp.116-149
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• 1977

• Composites Research
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• v.22 no.2
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• pp.30-36
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• 2009

In this paper, we propose the design method for the composite torque link of a landing gear for a helicopter. The composite torque link has to be light weighted and very stiff to keep the shock absorber in the landing gear of helicopter. The configuration and structural shape has to be designed in consideration of the RTM (Resin Transfer Molding) manufacturing process which is adopted to minimize the manufacturing cost. The mechanical properties are obtained through the coupon tests with the specimens made by the same manufacturing process for the composite structure. The optimal design process was performed through iterative modifications of the models which were verified by stress analysis using FEM. The composite torque link has lug-shaped parts and is very thick, so 3D Layered solid elements of ABAQUS were used to get the stress field including the stress components in thickness direction and non-linear static analysis using contact B.C. of rigid-deform condition was used to get the optimal design.

• Composites Research
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• v.19 no.3
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• pp.7-14
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• 2006

In this paper, an integrated probabilistic strength analysis was conducted to predict the reliability of a composite pressure vessel under inner pressure loading condition. As a probabilistic strength analysis, the probabilistic progressive failure model consisting of progressive failure model and Monte Carlo simulation was incorporated with a commercial FEA code, ABAQUS Standard, to perform the probabilistic failure analysis of composite structure which has a complex shape and boundary conditions. As design random variables, the laminar strengths of each direction were considered. Finally, from probabilistic strength analysis, the scattering of burst pressure could be explained and the reliability of composite pressure vessel could be obtained for each component. In case of composite structures in mass production, the effects of uncertainties in material and manufacturing on the performance of composite structures would apparently become larger. So, the probabilistic strength analysis is essential for the structural design of composite structures in mass production.

• Proceedings of the Korean Information Science Society Conference
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• 1998.10b
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• pp.54-56
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• 1998

동시에 다수의 사용자가 빠른 속도로 이미지 검색이 가능하도록 지원해주는 고차원 색인구조에 대한 효율적인 동시성 제어 방법은 매우 중요하지만 이에 대한 연구는 부족한 실정이다. 기존에 제안된 방법인 RLINK-트리는 링크를 적용시켜 다른 기법들에 비해 향상된 효율을 갖고 있지만 고차원 색인구조에 적용할 경우에는 문제가 발생한다. RLINK-트리에서는 고차원 색인구조의 효율적인 구성을 위한 재삽입 연산에 대한 동시성 제어를 고려하지 않고 있으며, 트리의 일관성을 유지하기 위해서 동시성 효율이 낮은 잠금 결합 방법을 사용하기 때문에 고차원 색인구조의 동시성 제어 기법에 그대로 적용하기에는 한계가 있다. 따라서, 본 논문에서는 고차원 색인구조의 효율적인 트리구성을 위해 수행되는 재삽입의 동시성 문제를 해결하면서 동시성 수준을 향상시킨 새로운 동시성 제어 알로리즘을 제안하고, 제안된 알로리즘을 고차원 색인구조에 적용시켜 동시성 제어가 효율적으로 제공될 수 있음을 증명한다.

• The monthly packaging world
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• s.280
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• pp.44-57
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• 2016

(사)한국포장재재활용사업공제조합은 자원의 재활용 촉진 및 환경친화적이며 효율적인 재활용 촉진을 위하여 그와 관련한 연구 및 기술개발을 수행 또는 지원을 바탕으로, 재활용 산업을 육성 발전시킴으로써 환경보전과 국민의 삶의 질 향상에 기여하며 "자원의 절약과 재활용 촉진에 관한 법률 제16조 제1항"의 규정에 의한 제품 포장재의 제조 수입 판매업자의 재활용 의무를 대행함을 목적으로 설립된 단체이다. 조합 연구소는 지난 4월 2015 포장재 자원순환 연차보고서를 발표했다. 본 고에서는 EPR대상 포장재 재활용 의무량 및 실력과 함께 연도별 포장재 재질 구조 등급별 시장조사, 재활용 현황에 대해 살펴본다.

• Journal of the Korea institute for structural maintenance and inspection
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• v.18 no.1
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• pp.75-83
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• 2014

In order to prevent brittle failure of concrete, steel fiber reinforcement is effective composite material. However ductility of steel fiber reinforced concrete may be limited due to shrinkage caused by large content of cement binder. Chemical prestressing for steel fiber reinforcement in cement matrix can be induced through expansive admixture and this can increase reinforcing effect of steel fiber. In this study, mechanical performances in concrete with CSA (Calcium sulfoaluminate) expansive admixture and steel fiber reinforcement are evaluated. For this work, steel fiber reinforcement of 1 and 2% of volume ratio and CSA expansive admixture of 10% weight ratio of cement are added in concrete. Mechanical and fracture properties are evaluated in concrete with steel fiber reinforcement and CSA expansive admixture. CSA concrete with steel fiber reinforcement shows increase in tensile strength, initial cracking load, and ductility performance like enlarged fracture energy after cracking. With appropriate using expansive admixture and optimum ratio of steel fiber reinforcement, their interactive action can effectively improve brittle behavior in concrete.