• Title/Summary/Keyword: Impact evaluation

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유한요소 해석을 통한 스포츠화의 런닝 시 착지충격 특성평가 (Evaluation of Landing Impact Characteristics of Sport Shoes in Running by finite Element Analysis)

  • 김성호;조진래;이시복;박승범
    • 한국운동역학회지
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    • 제19권2호
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    • pp.217-225
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    • 2009
  • 최근 들어 부강을 방지하고 경기력을 향상시킬 수 있는 스포츠화를 개발하기 위해 신체운동학과 생체역학을 반영한 연구가 전세계적으로 활발히 수행되고 있다. 하지만, 이러한 연구의 성골 여부는 스포츠화와 발의 동적 거동, 특히 착지 충격 특성 평가의 신뢰성에 절대적으로 좌우된다. 그 이유로는 코트 스포츠운동에 있어서 착지충격력이 예상치 못한 부상과 경기력의 주요한 요인이기 때문이다. 이 연구는 맨발과 대표적인 코트 스포츠화의 착지충격 특성을 평가하기 위해 유한요소 해석을 적용하였다. 사람의 발과 신발사이의 연계효과를 정확히 반영하기 위해 별도의 실험 데이터에 의존하지 않는 완전한 3차원 발-신발 FEM 모델을 생성하였다. 수치 시뮬레이션을 통해 FEM 모델의 신뢰성을 평가함과 동시에 여러 가지 스포츠화의 GRF, MIF 및 주파수 응답과 같은 착지충격 특성들을 분석하였다.

동작 가변적 3D 프린팅 낙상보호패드가 통합된 팬츠의 평가 (Evaluation of Pants Embedded with Motion Adaptable 3D Printing Fall Impact Protective Pads)

  • 이진숙;박정현;이정란
    • 패션비즈니스
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    • 제26권2호
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    • pp.143-155
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    • 2022
  • The purpose of this study was to develop protective clothing that could alleviate fall impacts. Fall impact protection pants for elderly women were designed, and motion adaptable hip pads and knee pads printed by 3D printing were integrated into the pants and evaluated. First, the design of the fall impact protection pants with variable motion was semi-loose fitting pants that could be worn and detached from the protective pad. A pad pocket was made in the lining inside the pants so that the protective pad could be fixed to the protective area. Second, in the evaluation of the appearance of the fall impact protection pants, the wearer group had a good score of 4.60 or higher for all questions on color, material, ease, and fit. In the evaluation of the insertion method of the protective pad, the flexibility of the pad, and the weight of the pad, the subjects' scores were 4.30~4.80. The fit of the fall impact protection pants was excellent in the texture and elasticity of the outside and inside of the pants. There was no discomfort due to the pad(4.60), and no difficulty in movement during wearing activities was reported. During squatting, it was evaluated as 4.80, indicating that the motion adaptable hip joint and knee pads were highly effective during operation.

청감실험에 의한 공동주택 바닥충격음의 평가등급 설정 (Rating Floor Impact Noise in Apartment Buildings Through Subjective Evaluation Tests)

  • 전진용;류종관
    • 한국음향학회지
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    • 제22권2호
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    • pp.88-95
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    • 2003
  • 본 논문에서는 바닥충격음의 감성적 상하한치를 기준으로 바닥충격음의 감성적 평가등급을 설정하기 위하여 바닥충격음 레벨에 따른 피험자의 주관적 반응을 현장 청감실험을 통하여 조사하였다. 표준 바닥충격원인 중량, 경량 충격음과 현재 일본에서 신 중량충격원으로 제안되고 있는 고무공충격음, 그리고 실제 충격음 (Jumping)을 대상으로 청감실험을 실시하였으며 청감실험에 사용된 주관적 반응의 평가척도로는 일본 건축학회에서 활용되고 있는 3개의 평가척도와 소음평가어휘를 활용한 평가척도를 사용하였다. 청감실험 결과, 바닥충격음 레벨에 따른 주관적 반응의 관계는 1차 회귀식으로 나타났으며, 감성적 하한치가 중량충격음의 경우 역A특성 가중 바닥충격음 레벨 (L/sub i, Fmax, AW/)이 46㏈, 경량충격음의 경우 역A특성 가중 규준화 바닥충격음 레벨 (L'/sub n, AW/)이 56㏈로 나타났다. 최종적으로 청감실험 결과에서 도출된 감성적 하한치의 기준으로 총 3등급의 평가등급이 설정되었다.

섬유강도와 적층구성이 CFRP적층판의 충격손상에 미치는 영향 (Influence of Fiber Strength and Stacking Sequences on Impact Damages of CFRP Composites)

  • 임광희;박노식;양인영
    • 한국자동차공학회논문집
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    • 제9권3호
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    • pp.210-220
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    • 2001
  • This paper aims at the evaluation on the characterization of CFRP laminate plates using falling weight impact tester. The experimentation was conducted on several laminates of different fiber and ply orientation. A system was built for the impact strength of CFRP laminates in consideration of stress wave propagation with using drop-weight impact tester as one of impact test. Absorbed energy of orthotropic composites with using T300 fiber, which are composed of the same fiber and stacking number is higher than that or quasi-isotropic specimen over impact energy 7J, but in case or using T700 fiber, much difference does not show. Also, absorbed energy of orthotropic composites with using T300 fiber, which are composed or stacking number and orientation became more than that of T700 fiber specimen; however great change doesn't show in case of quasi-isotropic specimens. It is found that influence was confirmed between impact energy and absorbed energy as the impact energy is increased with adding the falling weight.

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자동차 측면 충돌 안전도 평가 분석 (Safety Evaluation of Korean New Car Assessment Program - Side Impact)

  • 신재호;용기중
    • 자동차안전학회지
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    • 제6권2호
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    • pp.12-17
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    • 2014
  • The number of vehicle accidents related to the side impact has increased since 1990 in Korea, thus the side impact test has been performed as one of the major vehicle evaluations of the Korean New Car Assessment Program(KNCAP) in 2003. A total of 77 vehicles of eight different types(compact, small, semi-midsize, midsize, and large sedans and small, midsize, and large sports utility vehicles) were tested in side impact and side pole impact conditions. In this study, the head and thorax injury values(HICs and chest deflections) of the side impact tests performed between 2003 and 2013 were investigated in terms of vehicle type, test year, and test condition. The recent vehicles showed better safety performances(lower injury values) and similar injury patterns were obtained between side impact and pole side impact tests.

면내하중을 받는 복합적층판에 대한 충격하중 및 음향 해석 (Impact force and acoustic analysis on composite plates with in-plane loading)

  • 김성준;박일경;안석민
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2011년도 추계학술대회 논문집
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    • pp.244-249
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    • 2011
  • The potential hazards resulting from a low-velocity impact (bird-strike, tool drop, runway debris, etc.) on aircraft structures, such as engine nacelle or a leading edges, has been a long-term concern to the aircraft industry. Certification authorities require that exposed aircraft components must be tested to prove their capability to withstand low-velocity impact without suffering critical damage. In most of the past research studies unloaded specimens have been used for impact tests, however, in reality it is much more likely that a composite structure is exposed to a certain stress state when it is being impacted, which can have a significant effect on the impact performance. And the radiated impact sound induced by impact is analyzed for the damage detection evaluation. In this study, an investigation was undertaken to evaluate the effect in-plane loading on the impact force and sound of composite laminates numerically.

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감성평가 기반 바닥충격음 등급화 및 수인한도 설정 (Floor impact sound classification and setting Acceptable limit based on psychoacoustical evaluation)

  • 김성민;홍주영;전진용
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2014년도 추계학술대회 논문집
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    • pp.7-9
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    • 2014
  • An auditory experiment was conducted to establish annoyance criteria for floor impact noise in apartment buildings. Heavyweight floor impact sounds were recorded using an impact ball; the impact sound pressure level (SPL) together with the temporal decay rate (DR), which is quantified by the dB drop per second, was analyzed. For the experiment, A-weighted exposure levels of the heavy-weight floor impact sounds ranging 34~73 dB were evaluated at 3 dB intervals. Participants used a 7-point verbal scale to evaluate the level of annoyance from floor impact noise. The results show that the annoyance increases with increasing impact SPL and decreasing DR. Consequently, a classification and an acceptable level of floor impact sounds were proposed.

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폐기물 처리시설 입지선정의 효율화 방안에 관한 연구 - 여주군 폐기물 매립지 입지선정 사례를 중심으로 - (A Case Study on Simplified Assessment Method for Site Selection of the Waste Treatment Facilities in Korea)

  • 이무춘;구자건;김기철;권연정
    • 환경영향평가
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    • 제8권1호
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    • pp.71-79
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    • 1999
  • The comparative evaluation is the most effective method for site selection because the selection of waste treatment facility is to determine the optimum site out of limited candidate sites. This study adopted the ordinal scale evaluation, one of methods of comparative evaluation. The ordinal scale evaluation aims to determine the investigating items referring to the character of sites, to determine the importance factors for investigating items, and to determine the optimum site according to the quantitative evaluation. As a result of this study, the defects of the former reports on the environmental characteristics, such as obscurity of meaning and subjective statement, were reduced by the ordinal scale evaluation which is one of the quantitative evaluation methods. This ordinal scale evaluation method has some valuable advantages, such as, to be able to consider the cost-effect efficiency, to consider the objectiveness and the clearness of the reports on the environmental characteristics. Therefore the reducement of social complications about site selection of the indisposed facilities could be expected by this study.

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중량충격원에 따른 콘크리트 바닥판의 차음특성 분석 및 평가에 관한 연구 (Analysis and Evaluation of Impact Sound Insulation of Concrete Floor Structures in Response to Characteristics of Heavy-weight Impact Sources)

  • 유승엽;연준오;전진용
    • 한국소음진동공학회논문집
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    • 제19권10호
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    • pp.1062-1068
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    • 2009
  • In this study, the impact force levels of bang machine and impact ball were measured, then the heavy-weight impact sounds generated by the bang machine and impact ball were investigated. It was found that the heavy-weight impact sources generated through modal excitation, and the impact force of the impact ball was similar to that of real impact source. The heavy-weight impact sounds were also measured in the real apartments with different slab thickness and floor structures. The results showed that the floor impact sound levels in terms of $L_{iFmax,AW}$, generated by impact ball sounds were reduced by using the resilient isolators. The frequency characteristics of heavy-weight impact sounds at 125 and 250 Hz were consistent with the characteristics of impact force spectrum. However, the difference between the impact sounds and the impact forces were found at 63 and 500 Hz due to the resonance of the floor structure and flanking noise, respectively.

노후 잔교식 부두의 동적구조 안전성 평가에 관한 연구 (Evaluation of Dynamic Structural Safety of Aged Finger Pier)

  • 이성우;이상호;지기환
    • 한국전산구조공학회:학술대회논문집
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    • 한국전산구조공학회 1993년도 봄 학술발표회논문집
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    • pp.45-52
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    • 1993
  • Evaluation of structural stability of aged wharf structure of pier type is of great importance for both safety and rehabilitation, Series of field dynamic experiments were performed for berthing impact and the results were used to calibrate analysis model. Through dynamic analysis for design, berthing impact safety of old wharf structure were evaluated. In this paper the procedure and results of experiments and analysis are presented.

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