• Title/Summary/Keyword: Impact evaluation

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Evaluation of Impact Factor of High-Speed Railway Bridges from Dynamic Response under KTX Running (고속철도교량의 동적응답에 의한 충격계수 평가)

  • Yoon, Hye-Jin;Chin, Won-Jong;Kwark, Jong-Won;Hwang, Eui-Seung;Kim, Byung-Suk
    • Proceedings of the KSR Conference
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    • 2011.10a
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    • pp.1636-1640
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    • 2011
  • To consider dynamic magnification effect at the static design stage, impact factor is applied to design load. Current impact factor adopted EUROCODE without domestic verification through theoretical and experimental studies. This study evaluated impact factor of railway bridges from dynamic response under KTX running. Moving Average Method was applied to calculate impact factor. Investigation considering different type of bridges and tracks including velocity was conducted.

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Behavior of Woven-glass/Epoxy Composites after Impact Loading (접촉하중형태에 따른 복합재의 거동변화)

  • 이재준;김병식;황성식;김태우;김찬묵
    • Proceedings of the Korean Society For Composite Materials Conference
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    • 2002.05a
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    • pp.53-56
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    • 2002
  • External low-velocity impact loadings onto the composites cause reduction of stiffness and/or strength. The reductions indicate that internal(external) damages were developed within the composites. These damages could be matrix cracking, fiber/matrix debonding, or delamination between layers. In previous studies, damage evaluation have been done by applying secondary mechanical loading such as buckle-driven compressive, or fatigue, or flexural loadings. An evaluation method by applying indentation loadings on the composites was proposed. The load-displacement curves obtained from the indentation testing provided the extent of damages within the composites due to impact loadings.

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Harmonized EIA-Guidelines for German Railways Projects (독일에서의 철도사업 환경영향평가 지침)

  • Ch. Ufer, J. Koppel
    • Journal of Environmental Impact Assessment
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    • v.2 no.2
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    • pp.55-58
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    • 1993
  • After establishing the EIA(Environmental Impact Assessment) act in the Federal Republic of Germany there still remain methodical and substantial deficits. So nearly every environmental impact study went to be a matter of experiments. The requirement for standardization of data sampling and evaluation has permanently been increasing. This is meant to ensure quality standards for the assessment of environmental impacts as well as to maintain reliability required by the projecting company. Such a harmonization is of special importance because of the strongly accelerated expansion of traffic infrastructure caused by the reunification of Germany. That is why the guideline "EIA carried out" for the German Railways company is in process of development This guideline, focussing on practical demands, comprises impacts of railways, adequate sets of indicators, feasible tools for the prognosis and evaluation of environmental reactions. "EIA carried out" will be introduced not only as a manual but also through workshops and pilot studies.

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Effect of the Measuring Method of Reverberation Time Using Impulse Response Method on the Normalized Impact Sound Pressure Level (임펄스응답적분법을 이용한 잔향시간의 측정방법이 규준화 바닥충격음레벨에 미치는 영향)

  • Lee, J.W.;Kwon, Y.P.
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.16 no.1 s.106
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    • pp.34-39
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    • 2006
  • For the evaluation of the normalized impact sound pressure level, the reverberation time of the receiving room should be measured. This paper deals with the effect of the time constant of FFT analyzer and the measuring points on reverberation time. It is found that the time constant should be in the range between 10 ms and 35 ms. While the effect of measuring points on the reverberation time is significant when the bandwidth is narrow it is negligible in the evaluation of the normalized impact sound pressure level.

Finite Element Analysis for the Landing Impact Evaluation of Court Sport Shoes (코트 스포츠화의 착지충격 평가를 위한 유한요소 해석)

  • Kim, Seong-Ho;Cho, Jin-Rae;Ryu, Sung-Heon;Choi, Joo-Hyung
    • Proceedings of the KSME Conference
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    • 2004.04a
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    • pp.438-443
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    • 2004
  • Court sport shoes is consisted of several functional parts such as soles, upper and midfoot reinforcements. Currently, intensive research for court sport shoes considering functional parts is in progress world widely, but the shoes design relies only on the view point of kinesilogy and biomechanics until now. Thus, more scientific and reliable evaluation of shoes characteristics is definitely required. In this paper, we evaluate the landing impact of court sport shoes by using finite element method. We construct a shoes-leg coupled FEM model which can simulate effectively impact in running mode. From the numerical analysis results, the designer can establish the advanced design concepts and build up the detailed design standard for the specific court sport shoes under consideration.

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The Impact of Indigenous People's Pre-existing Information on Rice Farming: Findings from Laos

  • Bheomseok Kim;Taeyoon Kim
    • East Asian Economic Review
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    • v.27 no.1
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    • pp.3-31
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    • 2023
  • Dissemination of information can enhance smallholder farmers' agricultural outcomes and incomes in developing countries. However, the impact evaluation for new information can be inaccurate without considering pre-existing information that the indigenous people have used. This study explores qualitative causal links between existing agricultural information used by Lao smallholder farmers on rice yield and selling price with 180 household data. We categorized the pre-existing information into weather, farming technique, input, intermediate trader, and sales price. The source of each piece of information is used as an instrumental variable to overcome the endogeneity issue between information use and agricultural outcomes. Using farming technique information positively affects rice yields by 57.1% compared to those without that information. Moreover, intermediate trader and crop sales information result in 64.5% and 60.0% higher selling prices than non-user groups. A statistically significant causal relationship exists with agricultural outcomes. The more genuine impact should be measured with a newly updated impact evaluation approach that considers this pre-existing agricultural information.

A Study on Securing Objectivity in Small-Scale Environmental Impact Assessments Using Delphi Analysis

  • Dong-Myung CHO;Ju-Yeon LEE;Woo-Taeg KWON
    • Journal of Wellbeing Management and Applied Psychology
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    • v.7 no.3
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    • pp.73-95
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    • 2024
  • Purpose: Since August 2000, the small-scale environmental impact assessment system has prevented indiscriminate development. However, its qualitative reports lack objectivity and consistency. This study analyzes these issues through literature and expert surveys and proposes improvements. Research Methodology: Samples were selected based on regional consultation numbers. Mitigation measures were categorized into qualitative and quantitative factors. Issues were identified, and improvements suggested. The Delphi method helped select evaluation items and propose a scoring table. Results and Conclusions: The Delphi method selected 14 absolute and 22 relative evaluation items, excluding 3 invalid ones. A 100-point scoring table was created, with points assigned based on element significance. A 1-point bonus was added for top-scoring elements to promote eco-friendly planning.

Evaluation of Landing Impact Force of Court Sport Shoes at Running by Finite Element Analysis (유한요소 해석을 통한 코트 스포츠화의 런닝시 충격력 평가)

  • Kim, Seong-Ho;Cho, Jin-Rae;Ryu, Sung-Heon;Choi, Joo-Hyung
    • Proceedings of the KSME Conference
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    • 2004.11a
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    • pp.498-503
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    • 2004
  • A fundamental function of court sport shoes has been considered as the protection of human feet from unexpected injuries. But, recently its role for improving the playing competency is being regarded as a more important function. In connection with this situation, intensive efforts are being world-widely forced on the development of court sport shoes proving the excellent playing competency, by taking kinesiology and biomechanics into consideration. However, the success of this goal depends definitely on the shoes design based upon the reliable evaluation of shoes functional parts. This paper addresses the application of finite element method to the evaluation of landing impact force of court sport shoes. In order to reflect the coupling effect between leg and shoes accurately and effectively, we construct a fully coupled shoes-leg FEM model which does not rely on the independent experimental data any more. Through the numerical experiments, we assess the reliability of the coupled FEM model by comparing with the experimental results and investigate the landing impact characteristics of court sport shoes.

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