• Title/Summary/Keyword: Impact speed

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Life Cycle Assessment of Korean Tilting Train eXpress for Environmental Declaration of Product(EDP) (환경성적표지 인증을 위한 한국형 틸팅열차의 전과정평가)

  • Lee, Hyun-Bae;Kim, Yong-Ki;Lee, Kun-Mo
    • Proceedings of the KSR Conference
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    • 2010.06a
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    • pp.2262-2269
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    • 2010
  • A recent Tilting train development operation for existing line high speed, already developed "Korean Tilting Train eXpress(bellow TTX)" and that doing demonstration of operation. And TTX are going to commercial service in 2012. They are preparing Environmental Declaration of Product(bellow EDP) for offering environmental impact of TTX to customer. EDP calculated environmental impact of target product's whole life cycle(raw material and manufacturing, distribution, use, end of life) more quantity for that improving environmental impact and then certification them, it is using for that estimate some part of existence of specific pollutants, GHGs, energy consumption and recycling ratio. In this study, 1) analyze the process of getting EDP, 2) satisfy common criteria and each criteria(plan) in the Product Category Rules(bellow PCRs) provided KEITI, 3) according to ISO 14044, implementation of LCA. 4) These results be shown Characterized Impact(bellow CI) about each life cycle stage and six impact categories(ARD, GWP, OD, AD, EU, POC).

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Experimental Study of Impact Behaviors of the Membrane for LNG Storage Tank (LNG 저장탱크용 멤브레인의 충격거동에 관한 실험적 연구)

  • Kim, Young-Gyu;Kim, Chung-Kyun
    • Journal of the Korean Society of Safety
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    • v.10 no.4
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    • pp.68-74
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    • 1995
  • This paper analyzes the behaviors of the membrane under drop impact loadings using the acoustic emission technique. The analysis is useful for evaluating the strength of the membrane as well as for studying its damping characterisics due to the corrugation and the ring knot. The membrane for LNG storage tank is basically composed linear and circular elements. Two membrane specimens have approximately same drop impact mass and same drop speed. Locan 320 system with piezoelectric sensor is used in the experimental measurement. Experimental results for the membranes indicated that AE siganls having higher energies were generated with increasing drop impact loadings. It was confirmed that the ring knot. membrane has high absorption of drop impact loadings in comparison with the flat membrane. These results are very important to reliable design and to improve the safey of the membrane components.

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Ballistic behavior of steel sheet subjected to impact and perforation

  • Jankowiak, Tomasz;Rusinek, Alexis;Kpenyigba, K.M.;Pesci, Raphael
    • Steel and Composite Structures
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    • v.16 no.6
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    • pp.595-609
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    • 2014
  • The paper is reporting some comparisons between experimental and numerical results in terms of failure mode, failure time and ballistic properties of mild steel sheet. Several projectile shapes have been considered to take into account the stress triaxiality effect on the failure mode during impact, penetration and perforation. The initial and residual velocities as well as the failure time have been measured during the tests to estimate more physical quantities. It has to be noticed that the failure time was defined using a High Speed Camera (HSC). Thanks to it, the impact forces (average and maximum level), were analyzed using numerical simulations together with an analytical description coupled to experimental observations. The key point of the model is the consideration of a shape function to define the pulse loading during perforation.

High Speed Impact and Penetration Analysis using Explicit Finite Element Method (외연 유한요소 기법을 사용한 고속충돌 및 관통해석)

  • Paik, Seung-Hoon;Kim, Seung-Jo
    • Journal of the Korea Institute of Military Science and Technology
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    • v.8 no.4 s.23
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    • pp.5-13
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    • 2005
  • The impact of a long-rod penetrator into oblique plates with combined obliquity and yaw is investigated. The study was done using a newly developed three dimensional dynamic and impact analysis code, which uses the explicit finite element method. Through the comparison of simulation result with experimental result and other code's result, the adaptability and accuracy of the developed code is evaluated under the complex situation in which yaw angle and oblique angle exist simultaneously. As a result of comparison, it has found that deformed shape, residual length and velocity, rotational velocity of long-rod show good agreement with experimental data. Through this study, the applicability and accuracy of the code as a metallic armour system design tool is verified.

An Evaluation of Coarse Aggregate Mixed Effect on Impact Resistance of Fiber Reinforced Cement-Based Material (섬유보강 시멘트 기반 재료의 내충격 성능에 미치는 굵은 골재 혼입 영향 평가)

  • Lee, Eun-Jin;Kim, Gyu-Yong;Kim, Hong-Seop;Lee, Sang-Gyu;Son, Min-Jae;Yoon, Min-Ho
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2016.10a
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    • pp.37-38
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    • 2016
  • In this study, it evaluate the coarse aggregate mixed effect to impact resistance performance of the fiber reinforced cement-based material. The type of fiber is Hooked-ended steel fiber, and mixed 1vol.% in concrete and cement composites. The impact experiment was conducted by using a spherical shape projectile diameter of 25mm to 170m/s speed and Impact resistance performance was evaluated by measuring the fracture grade, fracture diameter and depth.

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Study on the moving device of press machine for forming impact reduction (성형충격 저감을 위한 프레스 구동기구에 관한 연구)

  • Kim, Jeong-Eon;Hong, Seok-Kwan;Kim, Jong-Deok;Heo, Young-Moo;Cho, Chong-Du;Kang, Jeong-Jin
    • Design & Manufacturing
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    • v.2 no.4
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    • pp.11-15
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    • 2008
  • In the sheet metal forming using a high speed press machine, driving device, such as crank, link, and knuckle mechanism, has to be designed in consideration of impact at a moment when press die contact with material, because the impact affects a dimensional accuracy of products and a life span of press die. In this study, dynamic analysis was performed using numerical simulation in order to verify the impact reduction effect for proposed double knuckle mechanism by estimating rolling and pitching moment of slide.

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Subthreshold Characteristics of a 50 nm Impact Ionization MOS Transistor (50 nm Impact Ionization MOS 소자의 Subthreshold 특성)

  • Yoon, Jee-Young;Ryu, Jang-Woo;Jung, Min-Chul;Sung, Man-Young
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2005.07a
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    • pp.105-106
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    • 2005
  • The impact ionization MOS (I-MOS) transistor with 50nm channel length is presented by using 2-D device simulator ISE-TCAD. The subthreshold slope cannot be steeper than kT/q since the subthreshold conduction is due to diffusion current. As MOSFETs are scaled down, this problem becomes significant and the subthreshold slope degrades which leads an increase in the off-current and off-state power dissipation. The I-MOS is based on a gated p-i-n structure and the subthreshold conduction is induced by impact ionization. The simulation results show that the subthreshold slope is 11.7 mV/dec and this indicates the I-MOS improves the switching speed and off-state characteristics.

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A Study on the Factors Influencing Citation Speed and Citation Frequency of Scientific Articles Using Bibliometric Analysis in South Korea (한국 과학기술 논문의 인용속도 및 인용빈도에 영향을 미치는 서지 요인에 관한 연구)

  • Kim, Wan-Jong
    • Journal of the Korean Society for Library and Information Science
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    • v.46 no.4
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    • pp.285-309
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    • 2012
  • The purpose of this study is to analyze whether bibliographic factors influence citation speed and the number of citations or not and whether citation speed affects the number of citations. Another purpose of this study is that if bibliographic factors carry out a significant role. For this analysis, this study is based on the assumption that all papers published by researchers in South Korea distributed power law shape. The main results of this study are as follows: First, the papers written by foreign first authors or reprint authors were cited more quickly from first citation speed and average citation speed. These papers were cited much more from first citation speed and average citation speed than by domestic first authors or reprint authors. The papers, collaborated by international researchers, were cited more quickly from first citation speed but were not different from average citation speed than by only domestic researchers. The papers, collaborated by international researchers, were cited much more than by only domestic stand-alone researchers. The number of authors and the impact factor influenced first citation speed, average citation speed and the number of citations. Second, the faster first citation speed and the slower average citation speed, the more papers were cited. First citation speed more affected the higher number of citations than the average citation speed. Third, all five bibliographic factors influenced the impact relationship from first citation speed to the number of citations through the moderating effect analysis. Fourth, only three bibliographic factors (the country of the first author; the country of the reprint author; the number of the coauthors) affected the impact relationship from first citation speed to the number of citations but two bibliographic factors did not influence through the moderating effect analysis.

A Study of NHTSA Oblique Impact MDB on the Vehicle Crash Behavior (NHTSA 경사 충돌 MDB 특성 변화에 따른 충돌 거동 연구)

  • Junsuk Bae;Ho Kim;Young Myoung So
    • Journal of Auto-vehicle Safety Association
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    • v.16 no.3
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    • pp.47-54
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    • 2024
  • MDB (Moving Deformable Barrier) is widely used over the world for the tests like frontal offset impact, side impact as well as frontal oblique impact. As autonomous vehicles are expected to come into the market in near future, new test protocols are required to secure the safety of the new type vehicles. MDB can be a versatile option for the new tests. In order to better understand the MDB, NHTSA oblique impact is chosen for the case study. NHTSA oblique impact test is about to be published and will be one of the newest test protocol using MDB, which bears technical know-how's built up from previous studies of MDB impacts. Compressive deformation behavior of the honeycomb of MDB is studied changing thickness of honeycomb structure. Delta-V is a good measure of impulse to the vehicle and is compared with varying weight of the MDB as well as its initial impact speed. Equivalence of delta-V with respect to momentum and kinetic energy is studied as well.

A Study on the Neck Injury Criteria Using BioRID-II during Very Low Speed Rear-end Collision (초저속 후방 추돌시 BioRID-II를 이용한 목 상해 지수 측정에 관한 연구)

  • Hong, Seungjun;Ryu, Hankyu;Kim, Youngeun
    • Transactions of the Korean Society of Automotive Engineers
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    • v.21 no.4
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    • pp.54-61
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    • 2013
  • Although typically classified as AIS 1, whiplash injuries continue to represent a substantial social problem with associated costs estimated at over $1 billion annually. The primary objective of this study was to determine the effects of seat positions(seatback angle, headrest height) on risk for whiplash injury in very low speed(ΔV=4~10km/h) rear-end impact. To accomplish this, rear impact seat carriage tests and simulations were conducted using the BioRID-II dummy seated in a mass production seat, which allowed for the adjustment of seatback angle and headrest height. Neck injury criteria(NIC, Nkm) were then compared for different ΔV and seat positions.