• Title/Summary/Keyword: Barrier protection

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The In-situ Dressing of CMP Pad Conditioners with Novel Coating Protection

  • Sung, James-C.;Kan, Ming-Chi
    • Proceedings of the Korean Powder Metallurgy Institute Conference
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    • 2006.09b
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    • pp.1142-1143
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    • 2006
  • Kinik Company pioneered diamond pad conditioners protected by DLC barrier ($DiaShield^{(R)}$ Coating) back in 1999 (Sung & Lin, US Patent 6,368,198). Kink also evaluated Cermet Composite Coating (CCC or $C^3$, patent pending) with a composition that grades from a metallic (e.g. stainless steel) interlayer to a ceramic (e.g. $Al_2O_3$ or SiC) exterior. The metallic interlayer can form metallurgical bond with metallic matrix on the diamond pad conditioner. The ceramic exterior is both wear and corrosion resistant. The gradational design of $C^3$ coating will assure its strong adherence to the substrate because there is no weak boundary between coating and substrate.

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A Study on Intelligent Railway Level Crossing System for Accident Prevention

  • Cho, Bong-Kwan;Jung, Jae-Il
    • International Journal of Railway
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    • v.3 no.3
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    • pp.106-112
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    • 2010
  • Accidents at level crossing have large portion on train accidents, and causes economical loss by train delay and operational interruption. Various safety equipments are employed to reduce the accident at level crossing, but existing warning device, and crossing barrier are simple train-oriented protection equipments. In this paper, intelligent railway level crossing system is proposed to prevent and reduce accidents. For train driver's prompt action, image of level crossing and obstacle warning message are continuously provided to train driver through wireless communication in level crossing control zone. Obstacle warning messages, which are extracted by computer vision processing of captured image at level crossing, are recognized by train driver through message color, flickering and warning sound. It helps train driver to decide how to take an action. Meanwhile, for vehicle driver's attention, location and speed of approaching train are given to roadside equipments. We identified the effect of proposed system through test installation at Sea train and Airport level crossing of Yeong-dong line.

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Preparation of Stock Solution for Electroless Nickel (무전해 니켈 도금액 제조)

  • 정승준;최효섭;박종은;손원근;박추길
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1999.11a
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    • pp.621-624
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    • 1999
  • Metalization technology of the fine patterns by electroless plating is required in place of electrodeposition as high-density printed boards(PCR) become indispensable with the miniaturization of electronic components. Electroless nickel plating is a suitable diffusion barrier between conductor meta1s, such as Al and Cu and solder is essetional in electronic packaging in order to sustain a long period of service. Moreover, Electroless nickel has particular characteristics including non-magnetic property, amorphous structure. wear resistance, corrosion protection and thermal stability In this study fundamental aspects of electroless nickel deposition were studied with effort of complexeing agents of different kinds. Then the property of electroless deposit are controlled by the composition of the deposition solution the deposition condition such as temperature and pH value and so on. the characteristics of the deposits has been carried out.

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Railway Noise: Current Status and Reduction Schemes (철도변 환경소음: 현황과대책)

  • Kim, Jeung T.;Kim, Tae M.;Son, Jeung G.
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2013.10a
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    • pp.563-563
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    • 2013
  • Railway noise has been a social issues nowadays in our community. This paper discusses the environmental noise problem along railway lines. We overview the noise level and noise exposed populations due to conventional and high speed train operation at first. Then we introduce variety of noise reduction schemes to protect the community based on an engineering approach. Some applicationcases to reduce the noise will be demonstrated. Finally, we propose the noise barrier tunnel as a tool of a generic solution to reduce the community noise along railway lines.

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Nanoparticles Modified With Cationic Thiol Surfactant as Efficient Inhibitors for the Corrosion of Carbon Steel

  • Azzam, Eid M.S.;Sami, Radwa M.;Alenezi, Khalaf M.;El Moll, Hani;Haque, A.
    • Journal of Electrochemical Science and Technology
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    • v.12 no.3
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    • pp.308-316
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    • 2021
  • In this work, we report synthesis, characterization and corrosion inhibition properties of cationic thiol surfactant-capped silver (SC-Ag-NPs) and gold (SC-Au-NPs) nanoparticles. SC-Ag-NPs and SC-Au-NPs were characterized using regular techniques include TEM. Corrosion study was carried out using carbon steel (CS) in 3.5% NaCl aqueous solution and characterized using multiple electrochemical techniques. Our results suggest that the paint containing SC-Ag-NPs and SC-Au-NPs endow efficient corrosion protection to the CS. Especially, SC-Au-NPs based paint form a stronger barrier between the metal and the corrosive ions, leading to better inhibition properties.

Crashworthiness Evaluation of Bridge Barriers Built with Hot-dip Zinc-aluminium-magnesium Alloy-coated Steel (고내식성 용융합금도금강판 적용 교량난간의 충돌성능 평가)

  • Noh, Myung-Hyun
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.17 no.3
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    • pp.171-176
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    • 2016
  • This paper proposes road safety facilities applying Hot-dip zinc-aluminum-magnesium alloy-coated steel sheets and coils to reduce the loss of function caused by the corrosion of steel in the service state. Vehicle crash simulations and full-scale crash tests were carried out to provide reliable information on evaluating the crash performance with the products of road safety facilities built with hot-dip zinc-aluminum-magnesium alloy-coated steel. From the results of the simulations and full-scale crash tests, the impact behaviors evaluated by the three-dimensional crash simulations considering the strain-rate dependency in a constitutive model were similar to those obtained from the full-scale crash test results. The full-scale crash test results met the crashworthiness evaluation criteria; hence, the proposed bridge barrier in this paper is ready for field applications.

Hazard Prevention Using Multi-Level Debris Flow Barriers (다단식(多段式) 유연성 토석류 방지시설에 관한 적용성 검토 연구)

  • Baek, Yong;Choi, Youngchul;Kwon, Oil;Choi, Seungil
    • Journal of the Korean GEO-environmental Society
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    • v.11 no.8
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    • pp.15-23
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    • 2010
  • Debris flows are a natural hazard which looks like a combination of flood, land and rock slide. Large rainfall in July 2006 produced several large scale debris flows and many small debris flows that resulted in loss of life and considerable property and railway damage, as was widely reported in the national media. The hazard "debris flow" is still insufficiently researched. Furthermore debris flows are very hard to predict. Flexible Ring net barriers are multi-functional mitigation devices commonly applied to rock fall or floating wood protection in floods, snow avalanches and also mud flows or granular debris flows, if properly dimensioned for the process or processes for which they are intended. Overtopping of the barriers by debris flows and sediment transport is possible, supporting the design concept that a series of barriers may be used to stop volumes of debris larger than are possible using only one barrier. The future for these barrier concepts looks promising because these barriers represent the state of art for such applications and are superior to many other available options.

An Experimental Study on the Fire Risk Assessment & Calculation Breakthrough Time through Permeation Test of Chemical Protective Clothing (화학보호복의 화재위험성 및 화학적 투과시험을 통한 파과시간산정에 관한 실험적 연구)

  • Ko, Jae-Sun;Park, Pyoung-Kyu
    • Fire Science and Engineering
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    • v.24 no.2
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    • pp.21-30
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    • 2010
  • We have test chemical resistance and flame retardant properties of chemical protective clothing Fabrics by the ASTM and ISO standard methods. The flame retardant test results show that polyethylene is poor in flame resistance but fluoroelastomer add to decabrom is excellent in flame resistance. Especially, nowadays heat protective clothing for firefighters, which is aluminized film layers laminated to aramid fabric, show the excellent flame resistance. However, the chemical resistance test results show that aluminium is high corrosive in 4M NaOH solution alone. The problem of corrosion can be overcome by employing multiple barrier film. Also, based on the result of flame retardant test, duel skin of polymer barrier film add to aluminum film and single skin of fluorinated rubber with flame retardant materials seems to be fit for the chemical protective clothing. Also the thermal protection and heat transfer test results show that TPP and HTI is increased assured that the continued study on fire risk assessment & chemical resistance of chemical protective clothing fabrics will contribute to the upgrade the performances of chemical protective clothing fabrics.

Micromorphology and development of the epicuticular structure on the epidermal cell of ginseng leaves

  • Lee, Kyounghwan;Nah, Seung-Yeol;Kim, Eun-Soo
    • Journal of Ginseng Research
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    • v.39 no.2
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    • pp.135-140
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    • 2015
  • Background: A leaf cuticle has different structures and functions as a barrier to water loss and as protection from various environmental stressors. Methods: Leaves of Panax ginseng were examined by scanning electron microscopy and transmission electron microscopy to investigate the characteristics and development of the epicuticular structure. Results: Along the epidermal wall surface, the uniformly protuberant fine structure was on the adaxial surface of the cuticle. This epicuticular structure was highly wrinkled and radially extended to the marginal region of epidermal cells. The cuticle at the protuberant positions maintained the same thickness. The density of the wall matrix under the structures was also similar to that of the other wall region. By contrast, none of this structure was distributed on the abaxial surface, except in the region of the stoma. During the early developmental phase of the epicuticular structure, small vesicles appeared on wallecuticle interface in the peripheral wall of epidermal cells. Some electron-opaque vesicles adjacent to the cuticle were fused and formed the cuticle layer, whereas electron-translucent vesicles contacted each other and progressively increased in size within the epidermal wall. Conclusion: The outwardly projected cuticle and epidermal cell wall (i.e., an epicuticular wrinkle) acts as a major barrier to block out sunlight in ginseng leaves. The small vesicles in the peripheral region of epidermal cells may suppress the cuticle and parts of epidermal wall, push it upward, and consequently contribute to the formation of the epicuticular structure.

The Study on control factor of WorldSID 50%ile dummy injury through AE-MDB side crash test (AE-MDB 측면 충돌 시험 시 WorldSID 50%ile dummy 상해치에 대한 제어인자 연구)

  • Hongyul Sun;Pyokyong Han;Jaesu Kim;Kiseok Kim;Ilsung Yoon
    • Journal of Auto-vehicle Safety Association
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    • v.6 no.1
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    • pp.5-9
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    • 2014
  • Over the past ten years, since the introduction of the side crash test regulation in Europe, much research work has been performed internationally to develop new and modified test procedures to improve the level of occupant protection offered by vehicles in side crash test. This research has been co-ordinated and finally contributed to development of an AE-MDB(Advanced European Moving Deformable Barrier) and WorldSID (Worldwide Side Impact Dummy). EuroNCAP(European New Car Assessment Program) has the plan to conduct AE-MDB side crash test using WorldSID from 2015 by replacing Progressive MDB and EuroSID II. Automobile manufacturers need to respond to these changes closely. This paper is to find dominant control factor and analyze it of WorldSID 50%ile dummy injury through AE-MDB side crash test by predicting best and worst condition. And control factors will be validated within EuroNCAP regulations. This paper is analyzed by DFSS(Design for six sigma) which contains 5 control factors and is evaluated by ANOVA with the data as a result of LS-DYNA analysis correlated with crash pulse from 50 kph AE-MDB side crash test using WorldSID 50%ile dummy.