• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2000년도 추계학술대회논문집
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• pp.636-642
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• 2000

A method for reducing the contact noise of the Progressive Multi-Leaf Spring was investigated. It was found that the contact noise between the main and the help springs is the main source of the noise through our experiments. The conclusions from our experiments were compared with those from our numerical analysis by use of ABAQUS. The main parameters for the unexpected noise in the leaf spring were investigated through structural analysis to make describing noise generation. The contact process between the two leaves is examined by numerical calculations by ABAQUS. The noise produced by the leaf spring could be dramatically reduced by changing the shape of help spring so as to remove a translational jump of the contact point between the main and the help springs. Even with the help spring of the new proposed shape the stiffness of the whole spring did not change much.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2011년도 제36회 춘계학술대회논문집
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• pp.279-282
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• 2011

가스 발생기 산화제 개폐 밸브에 사용되는 벨로우즈의 구조 해석 및 시험이 수행되었다. 해석은 상온 및 극저온에서 EJMA (Expansion Joint Manufacturing Association) 표준 및 상용 유한 요소 해석프로그램인 Abaqus v6.9를 이용하여 수행되었다. 스프링 강성, 응력 및 피로 수명 해석 결과들이 비교되었고 유한 요소 해석 결과에서 접촉 및 재질의 소성에 의한 영향을 살펴보았다.

• Computers and Concrete
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• 제16권4호
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• pp.531-544
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• 2015

The objective of this study was to examine the effect of repair mortar on the dynamic properties such as natural frequencies, mode shape and damping ratios of two story single span scale reinforced concrete building. To this end, two story single span scale reinforced concrete building having dimensions of 150 cm (width), 150 cm (length) and 135 cm (height) was constructed. Workmanship defects such as separation of material, faulty vibration application and bad gradation of the structure were properly evaluated. Dynamic properties of damaged structure were experimentally determined using Operational Modal Analysis (OMA). Detected defects in the structure were fixed by plastering with repair mortar. Dynamic properties of repaired structure were reevaluated by using the OMA method. Finite element software called Abaqus was used to numerically determine dynamic properties of the structure. Structure modeled as solid was subjected to Linear Perturbation Frequency Method. The changes in dynamic properties of structure after the repair process were comparatively studied by evaluating experimental and numerical results.

• 항공우주시스템공학회지
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• 제5권2호
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• pp.33-39
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• 2011

The vibration characteristic of tires is one of very important issues which heavily affect the noise and comfort on driving. Therefore, when the new tire is designed, the vibration characteristic of tire should be considered. In this paper, the vibration characteristic of non-pneumatic tire is investigated for geometric of NPT which is designed by cell angle of spoke. The analysis is based on the finite element method and used ABAQUS program, which is able to non-linear analysis. The material of NPT is used for the Ogden energy model, which is model of hyperelastic material. This paper investigate natural frequency and modal of NPT and compare result of NPT with it of pneumatic tire.

• 한국기계가공학회지
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• 제20권10호
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• pp.50-55
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• 2021

In this study, to create circular holes on an inclined conic face, we developed a novel process of vertical piercing on the plane before drawing, instead of applying an expensive cam-piercing method. The pierced holes are deformed during the drawing, and their shapes are affected by the size of the center hole. Using the Abaqus CAE program, the deformation tendency of the holes, according to the diameter of the center hole, was identified, and the diameter for securing the roundness of the side holes were determined through actual experiments. The developed process was successfully applied to mass production of the part, and a cost reduction is expected.

• Steel and Composite Structures
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• 제39권1호
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• pp.35-50
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• 2021

Eccentrically braced frames (EBFs) are utilized as a lateral resisting system in high seismic zones. Links are the primary source of energy dissipation and they are exposed to high deformation, which may lead to buckling. Web stiffeners were introduced to prevent buckling of shear link. AISC 341 provides the required vertical stiffeners for a shear link. In this study, different stiffener configurations were examined. The main objective is to improve the behavior of short links using different stiffener configurations. Pursuant to this goal, a comprehensive numerical study is conducted using ABAQUS. Shear links with different stiffener configurations were subjected to cyclic loading using loading protocol mandated by AISC 341. The results are compared in terms of energy dissipation and shear capacities and rupture index. The proposed stiffener configurations were further verified with different link length ratios, I-shapes and thickness of stiffener. Based on the results, the stiffener configuration with two vertical and two diagonal stiffeners perpendicular to each other is recommended. The proposed stiffener configuration can increase the shear capacity, energy dissipation capacity and the ratio of energy/weight up to 27%, 38% and 30%, respectively. Detailing of the proposed stiffener configuration is presented.

• Earthquakes and Structures
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• 제22권2호
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• pp.137-145
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• 2022

As steel is highly sensitive to temperature variations, fire exposure is more destructive in the case of steel structures in comparison to the concrete ones. The performance of an intermediate three-story steel moment frame with 4 spans was studied under the service load, thermal load and post-earthquake fire in this paper. Also, the effects of passive fire-protection materials such as ordinary cement-based and fire-retardant coatings were investigated. To model and analyze the structure; Abaqus software is utilized. In order to apply the earthquake effect, the push-over analysis method is employed. Changes in the stories deflection, endurance time and growth of nonlinear regions due to losses in the steel stiffness and strength, are among the issues considered in this study. As an interesting finding, the beams protected by ordinary cement-based coating could sustain the fire exposure at least for 30 minutes in all cases. The mentioned time is increased by employing a new fire-retardant protection, which could prevent significant loss in the structure resistance against fire, even after 60 minutes of exposure to fire.

• Steel and Composite Structures
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• 제44권1호
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• pp.141-154
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• 2022

This paper describes the experimental and numerical investigation on circular and octagonal CFDST short columns under concentric loading to study their responses to various internal circular steel tube sizes by the constant cross-sectional dimensions of the external circular and octagonal steel tube. The non-linear finite element analysis of circular and octagonal CFDST columns was executed using the ABAQUS to forecast and compare the axial behavior influenced by the various sizes of internal circular steel tubes. The study shows that the axial compressive strength and ductility of circular and octagonal CFDST columns were significantly influenced by inner steel tubes with the strengths of constituent materials.

• 한국컴퓨터정보학회:학술대회논문집
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• 한국컴퓨터정보학회 2021년도 제64차 하계학술대회논문집 29권2호
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• pp.105-106
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• 2021

자동사격통제기능 및 탄의 자동장전기능을 가진 최신 무기체계의 동력장치는 엔진, 변속기 및 냉각장치로 구성되어 있다. 이러한 동력장치를 정비하기 위해서는 엔진과 변속기를 결합 및 분리할 수 있는 특수공구의 사용이 필수적이다. 하지만, 기존 제품은 사용 특성에 따라 비틀림이 심하여 쉽게 마모되는 현상을 가진다. 본 연구에서는 강도저하로 인한 잦은 파손현상과 엔진 우측 연결부 조임 시 간접 현상에 자유로운 공구를 제안하고자 한다. 구조해석 프로그램(ABAQUS)을 통한 비틀림 강도 해석과 이를 바탕으로 최적 설계를 진행하여 제작된 공구는 기존 문제점을 해결하고 공인인증기관에서 토크의 130%의 비틀림 실험에서 문제없음을 확인하였다. 본 연구의 결과물은 동력장치 정비를 위한 특수공구의 국산화로 인한 경제적 측면에서 큰 도움이 될 것으로 사료된다.

• Structural Engineering and Mechanics
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• 제87권3호
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• pp.243-254
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• 2023

Engineering structures usually suffer from cracks. The crack geometry has an influence on the structural mechanical properties and subsequent crack propagations. However, as an extensively utilized method in fracture analysis, the extended finite element method provided by Abaqus fails to output the specific location and dimensions of fractures. In this study, a technique to capture the crack geometry is proposed. The technique is based on the invariant level set method (I-LSM), which can avoid updating the level set function during crack development. The solution is achieved by an open-source plug-in programmed by Python. Three examples were performed to verify the effectiveness and robustness of the program. The result shows that the developed program can accurately output the crack geometry in both the 2D and 3D models. The open-source plug-in codes are included as supplementary material.