• Title/Summary/Keyword: Protective Material

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Comparison of Thermal Protective Performance Test of Firefighter's Protective Clothing against Convection and radiation heat sources (대류와 복사 열원에 대한 특수방화복의 열보호 성능시험 비교)

  • Kim, Hae-Hyoung;Yoo, Seung-Joon;Park, Pyoung-Kyu;Kim, Young-Soo;Hong, Seung-Tae
    • Fire Science and Engineering
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    • v.31 no.2
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    • pp.17-23
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    • 2017
  • The test methods using convection (flame) and radiation heat sources were compared to evaluate the thermal protective performance of the firefighter's protective clothing. In particular, the influence of the outer shell, mid-layer, and lining constituting the firefighter's protective clothing on the thermal protective performance was compared for convection and radiation heat sources. Tests for the thermal protective performance were carried out according to KS K ISO 9151 (convection), KS K ISO 6942 (radiation), and KS K ISO 17492 (convection and radiation). When tested under the same incident heat flux conditions ($80kW/m^2$), the heat transfer index ($t_{12}$ and $t_{24}$) for the radiation heat source was higher than that for the convection heat source. This means that radiation has a lesser effect than convection. For the convection heat source, the lining had the greatest effect on the thermal protective performance, followed by the mid-layer and the outer shell. On the other hand, for the radiation heat source, the effect on the thermal protective performance was great in the order of lining, outer shell, and mid-layer. Convection and radiation have fundamentally different mechanisms of heat transfer, and different heat sources can lead to different thermal protective performance results depending on the material composition. Therefore, to evaluate the thermal protective performance of the firefighter's protective clothing, it is important to test not only the convection heat source, but also the radiation heat source.

Assessment of Equipotential Bonding and Electrical Continuity in Buildings (건축물의 등전위 본딩 및 전기적 연속성 평가)

  • Gil, Hyoung-Jun;Kim, Dong-Woo;Kim, Dong-Ook;Lee, Ki-Yeon;Moon, Hyun-Wook;Kim, Hyang-Kon
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2009.06a
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    • pp.385-386
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    • 2009
  • This paper deals with assessment of equipotential bonding and electrical continuity in Buinding by investigation on the spot at construction site. The assessment was carried out for continuity of steelwork in reinforced concrete structure, bonding conductor, protective conductor. A new grounding system based on international standards includes unity grounding system, structure grounding utilizing steel reinforced concrete, equipotential bonding, use of surge protective device.

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Monitoring of Retrofitted Reinforced Concrete Beams with Hybrid Fiber Reinforced Polymer (광섬유 센서를 이용한 복합 섬유 재료로 보강된 철근 콘크리트 보의 모니터링)

  • 이옥기;신영수;김기수;김종우
    • Proceedings of the Korea Concrete Institute Conference
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    • 2001.11a
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    • pp.509-514
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    • 2001
  • The Fibre-optic Bragg grating (FBG) sensor is broadly accepted as a structural health monitoring device for Fibre reinforced plastic (FRP) materials by either embedding into or bonding onto the structures. The accuracy of the strain measured by using the FBG sensor is highly dependent on the bonding characteristics among the bare optical fibre, protective coating, adhesive layer and host material. In general, the signal extracted from the embedded FBG sensor should reflect the straining condition of the host structure. This paper presents a theoretical model to evaluate the differential strains between the bare fibre and host material with different adhesive thickness and modulus of the protective coating of the embedded FBG sensor.

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Measurement of Changes in Work Function on MgO Protective Layer after H2-plasma Treatment (수소 Plasma 처리 후의 MgO 보호막에 대한 일함수 변화 측정)

  • Jeong, Jae-Cheon;Rhee, Seuk-Joo;Cho, Jae-Won
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.20 no.7
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    • pp.611-614
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    • 2007
  • The changes in the work $function({\Phi}_w)$ in the MgO protective layers after $plasma(Ar,\;H_2)$ treatment have been studied using ${\Upsilon}-focused$ ion beam $({\Upsilon}-FIB)$ system. The ${\Phi}_w$ was determined as follows: Ar-plasma $treatment({\Phi}_w=4.52eV)$, $H_2-plasma$ $treatment({\Phi}_w=5.65eV)$, and non-plasma $treatment({\Phi}_w=4.64eV)$. The results indicated that the H-plasma could not make any effective physical etching due to the small masses of hydrogen atoms and molecules while the hydration of H-plasma could grow some contaminating materials on the surface of MgO.

Inhibitory Effect of adding Phase Change Material (PCM) to Fire Fighter Protective Clothing on Burn Injuries (Phase Change Material (PCM) 소재 적용 소방보호복의 화상발생 억제효과에 관한 연구)

  • Lee, Jun Kyoung
    • Fire Science and Engineering
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    • v.30 no.3
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    • pp.16-22
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    • 2016
  • Fire fighters rely on fire fighter protective clothing (FFPC) to provide adequate protection in the various hazardous environments. To enhance its protection performance, the FFPC material must be thick and thus it is difficult to achieve weight reduction. One of the methods of overcoming this problem, the addition of phase change material (PCM) to FFPC, is a new technology. In previous studies, the researches was mostly related to the temperature characteristics of the fibers incorporating PCM, but little information is available about its effect on burn injuries. Thus, in this study, the inhibitory effects of adding PCM to FFPC on second degree burns were investigated through numerical calculations. Thermal analyses of biological tissues and FFPC with embedded PCM exposed to several fire conditions causing severe tissue damage were studied by using a finite difference method based on the Pennes bio-heat equation. FFPC with embedded PCM was found to provide significantly greater protection than conventional fire fighting clothing, because the heat of absorption due to the phase change within the material is used to limit the heat conduction of the material.

Evaluation of Pants Embedded with Motion Adaptable 3D Printing Fall Impact Protective Pads (동작 가변적 3D 프린팅 낙상보호패드가 통합된 팬츠의 평가)

  • Lee, Jinsuk;Park, Junghyun;Lee, Jeongran
    • Journal of Fashion Business
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    • v.26 no.2
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    • pp.143-155
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    • 2022
  • The purpose of this study was to develop protective clothing that could alleviate fall impacts. Fall impact protection pants for elderly women were designed, and motion adaptable hip pads and knee pads printed by 3D printing were integrated into the pants and evaluated. First, the design of the fall impact protection pants with variable motion was semi-loose fitting pants that could be worn and detached from the protective pad. A pad pocket was made in the lining inside the pants so that the protective pad could be fixed to the protective area. Second, in the evaluation of the appearance of the fall impact protection pants, the wearer group had a good score of 4.60 or higher for all questions on color, material, ease, and fit. In the evaluation of the insertion method of the protective pad, the flexibility of the pad, and the weight of the pad, the subjects' scores were 4.30~4.80. The fit of the fall impact protection pants was excellent in the texture and elasticity of the outside and inside of the pants. There was no discomfort due to the pad(4.60), and no difficulty in movement during wearing activities was reported. During squatting, it was evaluated as 4.80, indicating that the motion adaptable hip joint and knee pads were highly effective during operation.

Deposition of Protective Layer on Stealth Sheet and Evaluation of the Protected Sheet's Mechanical Performance (스텔스 소자의 보호층 도포 및 기계적 성능 평가 연구)

  • Sang Yeon So;Jae Won Hahn
    • Korean Journal of Optics and Photonics
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    • v.34 no.5
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    • pp.185-191
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    • 2023
  • We report the results of evaluating the hardness, flexibility, and adhesion between the protective layer and the stealth sheet after applying a protective layer to improve the practicality of the flexible stealth sheet. The result of the ISO 15184 pencil hardness test showed that the hardness increased from HB to 3H by three grades when a protective layer was applied. The flexibility evaluation was conducted by bending the material against cylinders of certain diameters and observing whether cracks occurred according to the ASTM D522 test method. The result showed that the minimum diameter was 0.125 inches. The adhesion was evaluated by using the ASTM D3359 test method, attaching and peeling off an adhesive strip to the protective layer and determining the proportion of the protective layer peeling off. The result was 5B, which is better than the military adhesion limit of 4B.

Evaluation of Physiological Responses and Comfort of Protective Clothing Using Charcoal Printing (숯 날염가공한 방호복의 인체생리반응 및 쾌적성 평가)

  • Chung Myung-Hee;Park Soon-Ja;Shin Jung-Sook;Koshiba Tomoko;Tamura Teruko
    • Journal of the Korean Society of Clothing and Textiles
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    • v.30 no.6 s.154
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    • pp.981-991
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    • 2006
  • The purpose of this study was to determine the practicability of an experimental protective clothing by identifying the human body's physiological responses to it as well as the human body's comfort level when wearing it, particularly with the use of a processed charcoal material. The experimental protective clothing came in two types: one whose outer side made use of polypropylene film, and the inner side, a non-woven rayon fabric; and one whose inner side made use of a non-woven fabric processed with charcoal with a 10% density. Experiments were conducted on five healthy adult women whose average age was 21. These experiments were conducted at a climatic chamber, in which the temperature and relative humidity were set below $28{\pm}1^{\circ}C\;and\;50{\pm}10%$, respectively, and were measured within a period of 60min, consisting of a 20-min rest period, a 20-min exercise period, and a 20-min recovery period. Based on the results of this study, the efficiency of the processed charcoal material was reviewed, and a database requiring the production of more functional and comfortable protective clothing materials was established.

Preparation of MgO Protective layer by reactive magnetron Sputtering (반응성 스퍼트링에 의한 MgO 유전체 보호층 형성에 관한 연구)

  • Ha, H. J.;Lee, W. G.;Ryu, J. H.;Song, Y.;Cho, J. S.;Park, C. H.
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1996.05a
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    • pp.59-62
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    • 1996
  • Plasma displays (PDP) as a large area wall-hanging display device are rabidly developed with flat CRT, TPT LCD and etc. Especially, AC Plasma Display Panels(AC PDPs) have the inherent memory function which is effective for large area displays. The memory function in AC PDPs is caused by the accumulation of the electrical charge on the protecting layer formed on the dielectric layer. This MgO protective layer prevents the dielectric layer from sputtering by ion in discharge plasma and also has the additional important roll in lowering the firing voltage due to the large secondary electron emission coefficient). Until now, the MgO Protective layer is mainly formed by E-Beam evaporation. With increasing the panel size, this process is difficult to attain cost reduction, and are not suitable for large quantity of production. To the contrary, the methode of shuttering are easy to apply on mass production and to enlarge the size of the panel and shows the superior adhesion and uniformity of thin film. In this study, we have prepared MgO protective layer on AC PDP Cell by reactive magnetron sputtering and studied the effect of MgO layer on the surface discharge characteristics of ac PDP.

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Encapsulation Method of OLED with Organic-Inorganic Protective Thin Films Sealed with Metal Sheet (금속판으로 봉인된 유-무기 보호 박막을 갖는 OLED 봉지 방법)

  • Lim, Su yong;Seo, Jung-Hyun;Ju, Sung-Hoo
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.26 no.7
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    • pp.539-544
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    • 2013
  • To study the encapsulation method for heat dissipation of high brightness organic light emitting diode (OLED), red emitting OLED of ITO (150 nm) / 2-TNATA (50 nm) / NPB (30 nm) / $Alq_3$ : 1 vol.% Rubrene (30 nm) / $Alq_3$ (30 nm) / LiF (0.7 nm) / Al (200 nm) structure was fabricated, which on $Alq_3$ (150 nm) / LiF (150 nm) as buffer layer and Al as protective layer was deposited to protect the damage of OLED, and subsequently it was encapsulated using attaching film and metal sheet. The current density, luminance and power efficiency was improved according to thickness of Al protective layer. The emission spectrum and the Commission International de L'Eclairage (CIE) coordinate did not have any effects on encapsulation process using attaching film and metal sheet The lifetime of encapsulated OLED using attaching film and metal sheet was 307 hours in 1,200 nm Al thickness, which was increased according to thickness of Al protective layer, and was improved 7% compared with 287 hours, lifetime of encapsulated OLED using attaching film and flat glass. As a result, it showed the improved current density, luminance, power efficiency and the long lifetime, because the encapsulation method using attaching film and metal sheet could radiate the heat on OLED effectively.