• 제목/요약/키워드: Impact System

검색결과 7,162건 처리시간 0.04초

평판 부착형 제진시스템을 이용한 구조기인 소음 저감에 관한 연구 (Noise control of a slab using the laminated composite damping system)

  • 황재승;김광용;홍건호
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2009년도 춘계학술대회 논문집
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    • pp.403-407
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    • 2009
  • It is reported that the heavy weight floor impact noise of a slab system is very sensitive to the location of microphone and impact load. In addition, it is known that the aspect raio, thickness and boundary condition of a slab also have great effect on the noise induced by impact load. However, the effect has been mainly evaluated by experimental test and numerical analysis is nearly performed to verify the effect quantitatively. In this study, the effect of the aspect ratio, thickness and boundary condition on the heavy weight floor impact noise is examined through numerical analysis for simple rectangular slab system. The results show that the thickness and boundary condition have a strong correlation with the noise of the slab, on the contrary, the aspect ratio has little relation with the noise.

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강재 충돌방호공의 선박충돌해석 (A bridge-vessel collision analysis of steel fender system)

  • 이계희;홍현석;백종균
    • 한국전산구조공학회:학술대회논문집
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    • 한국전산구조공학회 2003년도 가을 학술발표회 논문집
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    • pp.71-78
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    • 2003
  • In this study, the impact analysis for the steel fender system that designed for protection of collision between vessel and bridge was peformed. The size of objective collision vessel assumed as 3000 dead weight tonnage(DWT). The impact forces and the impact energies were estimated by formulas of several design codes, and the steel fender system was designed based on the estimated forces and energy. The bow of objective vessel was modeled as rigid body, and bridge substructure was modeled as fixed support. Since, the impact analysis have the dynamic nonlinear features, such as, material nonlinear, large deformation and contact, explicit structural analysis program was used. The analysis results presented that the impact forces formulas in codes have the sufficient conservativeness.

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Analysis for Evaluating the Impact of PEVs on New-Town Distribution System in Korea

  • Choi, Sang-Bong
    • Journal of Electrical Engineering and Technology
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    • 제10권3호
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    • pp.859-864
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    • 2015
  • This paper analyzes the impact of Plug-in Electric vehicles(PEVs) on power demand and voltage change when PEVs are connected to the domestic distribution system. Specifically, it assesses PEVs charging load by charging method in accordance with PEVs penetration scenarios, its percentage of total load, and voltage range under load conditions. Concretely, we develop EMTDC modelling to perform a voltage distribution analysis when the PEVs charging system by their charging scenario was connected to the distribution system under the load condition. Furthermore we present evaluation algorithm to determine whether it is possible to adjust it such that it is in the allowed range by applying ULTC when the voltage change rate by PEVs charging scenario exceed its allowed range. Also, detailed analysis of the impact of PEVs on power distribution system was carried out by calculating existing electric power load and additional PEVs charge load by each scenario on new-town in Korea to estimate total load increases, and also by interpreting the subsequent voltage range for system circuits and demonstrating conditions for countermeasures. It was concluded that total loads including PEVs charging load on new-town distribution system in Korea by PEVs penetration scenario increase significantly, and the voltage range when considering ULTC, is allowable in terms of voltage tolerance range up to a PEVs penetration of 20% by scenario. Finally, we propose the charging capacity of PEVs that can delay the reinforcement of power distribution system while satisfying the permitted voltage change rate conditions when PEVs charging load is connected to the power distribution system by their charging penetration scenario.

한국에서 환경평가의 부분으로서 건강영향평가의 통합적 접근에 관한 연구 (Integrated Approaches of Health Impact Assessment as part of Environmental Assessment in Korea)

  • 김임순;박주현;한상욱
    • 환경영향평가
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    • 제15권5호
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    • pp.309-322
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    • 2006
  • During the last decade, Health Impact Assessment (HIA) has been discussed worldwide as being an important tool for the development of healthy public policy. HIA has been advanced as a means of bringing potential health impacts to the attention of policy makers, particularly in sectors where health impacts may not otherwise be considered. HIA, a systematic assessment of potential health impacts of proposed public polices, programs, and projects, offers a means to advance population health by bringing public health research to bear on questions of public policy. In Korea, health-related items under current EIA (Environmental Impact Assessment) system can only be found in the categories of hygiene and public health. However, environment and public health are not adequately connected and also health is underestimated even though health is an important objective component for the implementation of Environmental Assessments (EA). As a result, health is not well integrated within criteria for investigating the impacts on environment. This study examines linkages for HIA from the related and relatively well-developed field of Prior Environmental Review System (PERS) which is similar to SEA and EIA in Korea.

공유수면 인공구조물 설치에 따른 해역이용협의서 작성실태 평가 (Assessment of Documentation Status of the Statement on the Sea Area Utilization according to Artificial Structure Installation in Public Water)

  • 엄기혁;이대인;김귀영;윤성순
    • 환경영향평가
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    • 제22권3호
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    • pp.265-276
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    • 2013
  • This study assessed documentation status of each environmental assessment items by analyzing the 243 case of marine EIS on the Consultation System of Sea Area Utilization. Observed rate of tidal elevation, current, temperature, salinity in maine environment were below 20%. The EFDC tool is applied substantially in hydrodynamic modeling. The verification process, however, is very insufficient using the recent observed data. Also, in-situ assessment rate of pelagic organism such as phytoplankton was below 50%, and assessment for Chlorophyll a was not accomplished. Ecological index evaluation for zooplankton and benthic ecosystem were not considered in statements. Especially, the rational assessment on the fisheries resources and protected species were very limited. It was necessary that the core assessment items (checklists) were established for environmental scoping. Furthermore, suggestion of information related to development, regional coastal management plan, aquaculture farms, and facilities were enhanced. The redundancy problem of proceedings between Environmental Impact Assessment and Sea Area Utilization Assessment System was improved.

수소버스 측면충돌 시험방법 연구 (Study on Side Impact Test Procedure of Hydrogen Bus)

  • 김경진;신재호;한경희;인정민;심소정;김시우
    • 자동차안전학회지
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    • 제13권4호
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    • pp.92-98
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    • 2021
  • Recently hydrogen fuel cell buses have been deployed for the public transportations. In order to introduce buses fueled by hydrogen successfully, the research results of hydrogen bus safety should be discussed and investigated significantly. Especially, Korean government drives research in terms of various applications of hydrogen energy to replace the conventional fuel energy resources and to improve the safety evaluation. Thus it is necessary to examine vehicle crashworthiness under side impact loadings. This study was focused on the simulation result evaluation of full bus model and simplified bus model with hydrogen fuel tank module and mounting system located below floor structure due to the significance of bus side impact accidents. The finite element models of hydrogen bus, fuel tank system and side impact moving barrier were set up and simulation results reported model performance and result comparison of two side impact models. Computational results and research discussion showed the conceptual side impact framework to evaluate hydrogen bus crashworthiness.

연안침식영향평가 제도 도입방안 연구 (A Study on the Introduction of Impact Assessment System for Coastal Erosion)

  • 신범식;신현화
    • 한국해안·해양공학회논문집
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    • 제36권2호
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    • pp.87-93
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    • 2024
  • 최근 기후변화 영향에 의한 해수면 상승 및 이상 고파랑 발생, 지속적인 항만·어항개발 등 인공구조물 설치 등으로 연안침식의 피해가 증가하고 있는 추세이다. 본 연구에서는 연안에서 시행되는 개발사업과 침식저감사업 수행 시 진행되는 환경영향평가, 해역이용협의, 재해영향평가, 연안재해 위험평가 제도의 범위와 방법에 대해 분석하여 각각의 문제점을 파악하고, 개선방안을 도출하여 연안침식에 대한 영향을 최소화 할 수 있는 연안침식영 향평가제도의 도입방안을 제안하였다.

건식이중바닥구조의 중량충격음에 대한 실험적 평가 - 지지구조 및 천장구조 구성에 따른 영향 - (Experiment Evaluation for the Heavy-weight Impact Sound of Dry Double-floor System - Effect of Rubber Hardness and Ceiling Structure -)

  • 연준오;김경우;최현중;양관섭;김경호
    • 한국소음진동공학회논문집
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    • 제23권1호
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    • pp.34-40
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    • 2013
  • The 1st assessment(performance test) was applied to assure the floor impact sound performance for developing the dry double-floor with the change of rubber hardness of the upper panel's support and the ceiling structure of the sub-floor. Depends on the change of the rubber hardness in sub-structure, the heavy-weight sound impact value is improved up to 3 dB, and the light-weight sound impact value is moved up to 21 dB, comparing with the bare-slab. Also, the improved value for the floor impact sound conjugating with the sub-floor's ceiling was 5 dB. Based on this result, the 2nd assessment(performance test) was made the state that the rubber hardness of the sub-floor support was ranged between 50 and 70 for considering the stability of walking patients. In addition to this process, the assessment was carried out with a variety of ceiling structure applied to the dry double-floor structure with the air flow system on the sub-floor's ceiling. The result for the 2nd assessment proved that TYPEII-3 had the better sound reduction performance in the heavy-weight impact sound test than other types, and also for the light-weight impact sound TYPEII-3 had the 29 dB sound reduction performance overall. Henceforth, based on the result the research for the sound reduction performance from the floor impact sound shall be ongoing process as well as the development of a double-dry floor and a sound reduction ceiling to suitable on the field.

건식 이중바닥구조의 중량충격음 저감성능 평가 (Evaluation for The Heavy-weight Impact Sound Reduction Performance of Dry Double-Floor System)

  • 연준오;김경우;최현중;양관섭;김경호
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2012년도 추계학술대회 논문집
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    • pp.280-285
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    • 2012
  • The 1st assessment (performance test) was applied to assure the floor impact sound performance for developing the dry double- floor with the change of rubber hardness of the upper panel's support and the ceiling structure of the sub-floor. Depends on the change of the rubber hardness in substructure, the heavy-weight sound impact value is improved up to 3 dB, and the light-weight sound impact value is moved up to 21 dB, comparing with the bare-slab. Also, the improved value for the floor impact sound conjugating with the sub-floor's ceiling was 5dB. Based on this result, the 2nd assessment (performance test) was made the state that the rubber hardness of the sub-floor support was ranged between 50 and 70 for considering the stability of walking patients. In addition to this process, the assessment was carried out with a variety of ceiling structure applied to the dry doublefloor structure with the air flow system on the sub-floor's ceiling. The result for the 2nd assessment proved that TYPE-11 had the better sound reduction performance in the heavy-weight impact sound test than other types, and also for the light-weight impact sound TYPE-11 had the 29 dB sound reduction performance overall. Henceforth, based on the result the research for the sound reduction performance from the floor impact sound shall be ongoing process as well as the development of a double-dry floor and a sound reduction ceiling to suitable on the field.

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모자이크 패턴 전극 압전 페인트 센서를 이용한 충격 위치 검출 (Impact Localization Using Piezoelectric Paint Sensor with Mosaic Pattern Electrodes)

  • 강상현;강래형
    • 항공우주시스템공학회지
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    • 제13권2호
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    • pp.19-25
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    • 2019
  • 구조물의 충격 위치 검출을 위해 본 연구그룹에서는 압전 페인트 센서를 연구하고 있다. 압전 페인트는 고주파 신호 및 충격에 민감한 특성으로 인하여 충격 감지에 사용할 수 있다. 또한, 압전 페인트 센서는 세라믹 센서가 적용될 수 없는 곡선 또는 복잡한 구조에 코팅될 수 있으며 외부 전원을 필요로 하지 않는다. 충격을 검출하기 위해 모자이크 패턴 전극을 시험편 위에 코팅하였고, 충격 신호는 충격이 발생한 전극부에서 얻을 수 있었다. 보다 더 정확한 충격 위치 검출을 위해서는 전극을 더 많은 부분으로 나누어 해당 전극부로부터 충격 데이터 수집이 필요하다. 본 연구에서는, 데이터 수집을 위하여 가볍고 저렴한 간단한 멀티채널 데이터 수집 시스템을 개발하였다. ARM Cortex-M3의 UART 통신을 이용하여 총 4채널의 데이터를 수집하였다.