• Title/Summary/Keyword: protection design

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Design of Occupant Protection Systems Using Global Optimization (전역 최적화기법을 이용한 승객보호장치의 설계)

  • Jeon, Sang-Ki;Park, Gyung-Jin
    • Transactions of the Korean Society of Automotive Engineers
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    • v.12 no.6
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    • pp.135-142
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    • 2004
  • The severe frontal crash tests are NCAP with belted occupant at 35mph and FMVSS 208 with unbelted occupant at 25mph, This paper describes the design process of occupant protection systems, airbag and seat belt, under the two tests. In this study, NCAP simulations are performed by Monte Carlo search method and cluster analysis. The Monte Carlo search method is a global optimization technique and requires execution of a series of deterministic analyses, The procedure is as follows. 1) Define the region of interest 2) Perform Monte Carlo simulation with uniform distribution 3) Transform output to obtain points grouped around the local minima 4) Perform cluster analysis to obtain groups that are close to each other 5) Define the several feasible design ranges. The several feasible designs are acquired and checked under FMVSS 208 simulation with unbelted occupant at 25mph.

A Study on the Design, Fabrication and Characteristics Test of 25KJ Superconducting Magnetic Energy Storage (25KJ 초전도 에너지 저장장치의 설계,제작 및 특성 시험)

  • 홍원표;원종수;이송엽;이승원
    • The Transactions of the Korean Institute of Electrical Engineers
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    • v.37 no.10
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    • pp.683-693
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    • 1988
  • For the economical and reasonable operation of electric power system according to continual increase of electric power demand and decrease of load factor, the potential application of superconducting magnertic energy storage [SMES] with high efficiency and fast response in the electric utility is receiving attractive attension. In the light of this background, to confirm the basic principle of SMES, theoretical study, design technique and fabrication procedure for superconducting coil, current lead, cryostat, measuring and protection system of SMES are described in detail. Especially, a new design technique for superconducting coil and current lead is porposed and it was proved experimentally by the performance test of SMES which is developed for the first time in our country. At the peak operating current 200A, the maximum magnetic field amd stored energy of the coil are 3.52T and 2500J, espectively. The thermal and mechanical stability of 2500J SMES is also confirmed experimetally by its characteristics test, AC loss, protection system, charge and discharge test. The experimetal results show good characteristics of energy storage system.

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Grounding Electrode Design for the Reduction of Hazardous Voltage in Lightning Protection (위험전압 저감을 위한 피뢰설비용 접지전극의 설계)

  • Lee, B.H.;Lee, S.C.;Eom, J.H.
    • Proceedings of the KIEE Conference
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    • 2000.07c
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    • pp.2071-2073
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    • 2000
  • Grounding electrode design is an important part in lightning protection, and the limit of hazardous voltages (step and touch voltages) below the permissible voltage for human body has been the main goal of grounding electrode design. In this paper, the grounding electrode for the reduction of hazardous voltages was designed and evaluated newly. It was known that the inclined auxiliary grounding conductors installed outside the grounding mesh grid are very effective to reduce the step and touch voltages.

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The F/S Concept Design for Solid Motor Thrust Vector Control (고체모터 추력제어를 위한 F/S 개념 설계)

  • Kim, Byung-Hun;Kwon, Tae-Hoon;Cho, In-Hyun
    • Aerospace Engineering and Technology
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    • v.7 no.1
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    • pp.170-176
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    • 2008
  • The concept design of Flexible Seal for thrust vector control of solid motor was performed. Through the concept design, the optimum pivot point of flexible seal, cross-section configuration of flexible seal and thermal protection system from combustion gas was decided. The pivot point of flexible seal has aft pivot type and cross-section view is conical type. For satisfying a spring torque rate, the shear modulus of rubber has the value of under about 0.6MPa and failure shear stress has over about 2.5MPa.

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Seismic Performance of the Anchor System of Bearing-protection Devices Preventing the Unseating Failure of Bridges (낙교 방지를 위한 받침보호장치의 앵커부 내진성능)

  • Jeong, Hyeok-Chang;Kim, Min-Su;Park, Kwang-Soon;Ju, Hyeong-Seok;Kim, Ick-Hyun
    • Journal of the Earthquake Engineering Society of Korea
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    • v.14 no.6
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    • pp.45-53
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    • 2010
  • The unseating failure of bridges, which is one of the most severe types of damage leading to the loss of transportation function, should be avoided in earthquakes. As a measure of prevention of unseating failure resulting from the failure of bearings, bearing-protection devices are frequently used. They are installed beside the bearings and protect the bearings by resisting a seismic load transmitted from the superstructure. In order to show appropriate seismic performance, the strength of anchors as well as of device bodies should be confirmed. In Korea, they have been installed only according to the design provided by device agents, because a proper design method for the anchors has not been established. In this study the performance of bearing-protection devices with various heights of concrete bed blocks has been investigated experimentally, and a proper design method has been proposed to secure seismic performance.

Development of Firefighters' Personal Protective Clothing with Nomex Honeycomb Fabric and its Protective and Comfort Evaluation (노멕스 허니콤 구조 직물을 적용한 소방관용 특수방화복 개발 및 이의 보호 쾌적 성능평가)

  • Jung, Jae-Yeon;Ku, Ponjun;Kim, Do Hyung;Kwon, Min-Jae;Kang, Sungwook;Choi, Jeong-Yoon;Lee, Joo-Young
    • Fashion & Textile Research Journal
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    • v.21 no.5
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    • pp.606-617
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    • 2019
  • The present study newly developed a firefighters' protective jacket and pants using a Nomex honeycomb structured layer (HPC) in cases of being exposed to flashover or flameover. This study evaluated the protective and comfort functions of an HPC compared to the current KFI firefighters' protective clothing (FPC). The results are as follows. First, thermal protective performance (TPP) of fabric layers was 2.75 times greater for HPC than FPC at $125kW/m^2$. Second, the predicted second and third degree burn areas were smaller for HPC than FPC when using a flame manikin. Third, thermal insulation using a thermal manikin was 0.2 clo greater for HPC than FPC. Fourth, there were no marked differences in maximal performance, mobility, and microclimate temperature/humidity between FPC and HPC through human wear trials. The thermal insulation of HPC was higher than that of FPC; however, any negative effect of HPC thermal insulation on the comfort functions for firefighters was not found. In conclusion, the newly-developed HPC provided more protection in reducing burn injuries from $125kW/m^2$, while no negative impact on maximal performance, mobility and thermal comfort functions of firefighters, which is appropriate for quick-evasive tactics at the flashover, flameover or back draft fires.

A Study on ESD Protection Circuit with Bidirectional Structure with Latch-up Immunity due to High Holding Voltage (높은 홀딩 전압으로 인한 래치업 면역을 갖는 양방향 구조의 ESD 보호회로에 관한 연구)

  • Jung, Jang-Han;Do, Kyung-Il;Jin, Seung-Hoo;Go, Kyung-Jin;Koo, Yong-Seo
    • Journal of IKEEE
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    • v.25 no.2
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    • pp.376-380
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    • 2021
  • In this paper, we propose a novel ESD protection device with Latch-up immunity properties due to high holding voltages by improving the structure of a typical SCR. To verify the characteristics of the proposed ESD circuit, simulations were conducted using Synopsys TCAD and presented compared to existing ESD protection circuits. Furthermore, the variation of electrical properties was verified using the design variable D1. Simulation results confirm that the proposed ESD protective circuit has higher holding voltage properties and bidirectional discharge properties compared to conventional ESD protective circuits. We validate the electrical properties with post-design TLP measurements using Samsung's 0.13um BCD process. And we verify that the proposed ESD protection circuit in this paper is well suited for high voltage applications in that it has a latch-up immunity due to improved holding voltage through optimization of design variables.

Fire Protection System for Ubiquitous Environment (유비쿼터스 환경을 위한 소방시스템)

  • Kang, Won-Chan;Kim, Nam-Oh;Min, Wan-Ki;Shin, Suck-Doo;Kim, Young-Dong
    • The Transactions of the Korean Institute of Electrical Engineers P
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    • v.54 no.3
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    • pp.141-147
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    • 2005
  • In this paper, We are going to propose the fire protection system with using CAN(Controller Area Network). The larger, higher and deeper buildings are, the more dangerous people are when fire happens. We should be aware of the problems of prior fire protection system. Therefore, we construct embedded system based on CAN communication that is capable of N:N communication, and build independent fire protection system. If the fire is occurred on the building, the problem is that how fast we can detect the fire and put off it by using available system. this is major factor that reduces damage of our wealth. therefore in this studies We would like to design more stable system than current system. this system that is based on CAN communication which is available N:N communication constructs and is designed to compensate for each fault so that our aim is to reduce the line of system and cost of installation and to suppose future type fire protection system. We are simulated by NIST FDS(Fire Dynamics Simulator) to prove the efficiency of this system.

Estimation of Absorbing Capacity from Rockfall Protection Fences (도로 낙석방지울타리의 낙석지지능력 평가 연구)

  • Hwang, Young-Cheol
    • Journal of the Korean GEO-environmental Society
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    • v.3 no.4
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    • pp.59-66
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    • 2002
  • Designs for rockfall protection systems must consider rock and soil types, the angle of the slope, conditions on top and the toe of the affected area. Rockfall protection fence is installed to block for falling rock from cut slopes and this is one of the most common rockfall protection measures. The capability of the fence is provided that sum of capability of poly vinyl chloride coated wire mesh, steel support and wire rope respectively. But in some case, the rockfall protection fence was not supported rockfall energy less than total capability of the fence through the full scale rockfall tests. Therefore, the objectives of this paper are to indicate the problems of fence capability and to improve the design specifications for the fence.

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전기체 구조시험을 위한 고성능 과하중 방지 모듈 개발

  • Chae, Dong-Chul;Kim, Sung-Chan;Hwang, Gui-Chul;Sung, Kyung-Jin;Shim, Jae-Yeul;Hwang, In-Hee
    • Aerospace Engineering and Technology
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    • v.3 no.2
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    • pp.208-216
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    • 2004
  • Advanced overload protection module for full scale airframe structural test was developed by improving the existing overload protection module. When performing the full scale airframe structural test, overload can be applied to the test article due to unexpected situations such as system shutdown, test article failure, and deficiency of design strength. Therefore, the overload protection module is needed for protecting the test article in unexpected overload situations. In this paper, the function of the existing overload protection module was summarized for each component and the problems encountered when using it in structural test were analyzed in addition, the development of advanced overload protection module was described.

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