• 한국해양공학회지
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• 제33권1호
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• pp.85-91
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• 2019

In a cryogenic storage structure, the insulation system is in an environment in which fluid impact loads occur throughout the lifetime of the structure. In this study, we investigated the effect of repetitive impact loading on the mechanical performance of glass fiber-reinforced polyurethane foam. The repeated impact loading test was conducted in accordance with the required impact energy and the required number of repetitive impacts. The impact behavior of glass fiber-reinforced polyurethane foam was analyzed in terms of stress and displacement. After the impact test, the specimen was subjected to a compression test to evaluate its mechanical performance. We analyzed the critical impact energy that affected mechanical performance. For the impact conditions that were tested, the compressive strength and elastic modulus of the polyurethane foam can be degraded significantly.

• 소성∙가공
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• 제19권4호
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• pp.217-223
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• 2010

The objective of this study is to propose the FE model for mechanical clinched joint using cohesive zone model to analyze its failure behavior under impact loading. Cohesive zone model (CZM) is two-parameter failure criteria approach, which could describe the failure behavior of joint using critical stress and fracture toughness. In this study, the relationship between failure behavior of mechanical clinched joint and fracture parameters is investigated by FE analysis with CZM. Using this relationship, the critical stress and fracture toughness for tensile and shear mode are determined by H-type tensile test and lap shear test, which were made of 5052 aluminum alloy. The fracture parameters were applied to the tophat impact test to evaluate the crashworthiness. Compared penetration depth and energy absorption at the point where 50% of total displacement in result of FE analysis and experiment test for impact test, those has shown similar crashworthiness.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2007년도 춘계학술대회 논문집
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• pp.409-412
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• 2007

A motorcycle helmet is the best means to protect the head of bike's driver and it is directly connected to a driver's life. Prior to producing of the helmet, it has to be passed the process of impact test to evaluate of its safety. This test evaluates peak acceleration and H.I.C (Head Injury Criteria). This paper analyzes impact test with finite element method to find the behavior of helmet during the test. Also, the effect of impact sites on the helmet was evaluated to improve the thickness distribution of the helmet.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2006년도 추계학술대회논문집
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• pp.371-371
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• 2006

The purpose of this study is to provide a fundamental data for efficient and economical reduction method and predict ion method of floor impact noise. In order to get the useful results, the measurement on the vibration transmission characteristics of standard test building with four rooms by using heavy and light-weighed impact source were carried out. In this measurement various conditions such as the change of test structure construction, the pick-up sensor location, the excitation posit ion, and the resilient material types were applied to get the vibration characteristics transmitted from excitation room to adjacent rooms.

• 소성∙가공
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• 제16권5호통권95호
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• pp.370-374
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• 2007

A motorcycle helmet is very essential to protect the head of driver and it is directly connected to driver's life. Prior to producing the helmet, it has to be passed the process of impact test to evaluate its safety. This test evaluates peak acceleration and head injury criteria (H.I.C.). This paper simulates the impact test with finite element method to find the behavior of helmet during the test. Also, the effect of impact sites on the helmet was evaluated to improve the thickness distribution of the helmet.

• Nuclear Engineering and Technology
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• 제55권7호
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• pp.2407-2418
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• 2023

Internal replaceable electronic module substitutions can impact EMC (ElectroMagnetic Compatibility) qualification testing and results if EMC testing is conducted at the cabinet level. The impact of component substitutions on EMC qualification results therefore should be evaluated. If a qualitative evaluation is not adequate to ensure that the modified product will not impact the cabinet level EMC qualification results, a new qualification testing should be conducted. Component level retesting should be conducted under electromagnetically equivalent conditions with the cabinet level test. This paper analyzes the propagation of conducted susceptibility test waveforms in a representative cabinet and evaluates the impact of component substitutions on cabinet level EMC qualification results according to the location of the replacement items. A guideline for a qualitative evaluation of the impact of component substitutions is described based on the propagation of the conducted susceptibility test waveforms. A module level test method is also described based on an analysis of the shielding effectiveness of the cabinet.

• 한국지진공학회논문집
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• 제22권7호
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• pp.369-378
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• 2018

Full-scale seismic retrofit of old and deteriorated masonry buildings requires a lot of cost and time. In such buildings, installing an emergency evacuation space can be considered as an alternative. In this study, requirements of the earthquake-proof table used as an emergency evacuation space for buildings hit by earthquake are investigated. Load conditions required for the table, including the impact effects due to building debris drop, are explained. To investigate the impact effects in more detail, weight drop test is performed for an prototype earthquake-proof table. In the test, the weight of the falling object and free fall height were considered as the main test parameters. The results showed that the duration of impact is very short (0.0226~0.0779sec), and thus the impact forces increase to 15.8~45.2 times the weight of the falling object. Based on these results, design considerations and performance verification criteria of the earthquake-proof table as an emergency evacuation space are given.

• Composites Research
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• 제22권6호
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• pp.18-22
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• 2009

본 논문에서는 복합적층판의 저속충격실험을 통하여 충격력과 충격거동의 관계를 확인하였다. 또한 육안으로 확인하기 어려운 손상역영을 탐지하기 위하여 비파괴검사인 c-scan을 이용하였다. CAI실험을 통하여 저속충격을 받은 복합적층판의 압축강도를 측정하였다. 저속충격실험, 비파괴검사, CAI실험을 통한 복합적층판의 저속충격거동 특성을 확인하기 위해 몬테카를로 시뮬레이션을 적용하여 가상의 확률분포를 나타냈다. 가시화된 통계적 확률분포를 이용하여 주요변수들을 비교 및 분석하였다.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1995년도 추계학술대회 논문집
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• pp.822-825
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• 1995

Linear elastic stress analysis of aluminum wheel was studied using ANSYS and Unigraphics. The load condition of wheel impact test was replaced whit static force using energy valance concept. And the results were compared with strain gaga test. The test results were good agreement with analysis results.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1995년도 가을 학술발표회 논문집
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• pp.150-154
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• 1995

The purpose of this study is to evalute the mechanical and the anti-corrosion characteristics of cementitious, organic coatings on steel plates. Tests are performed according to KS M 5331, 5250, etc'. For the test, we used water based epoxy, Tar epoxy, the red lead, and cementitious anti-corrosion coatings. The results of adhension tests satisfying the requirements in relevant standards The impact test shown that the impact test shown that the impact resistance of cementitious anti-corrosion test, rred lead, epoxy, cementitiouse show good corrosion resistance.