• 제목/요약/키워드: liner

검색결과 1,226건 처리시간 0.025초

HTPB 라이너와 PCP 추진제와의 접착에 관한 연구 (A study on the adhesion of HTPB liner and PCP propellant)

  • 홍명표;서태석;임유진
    • 한국추진공학회지
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    • 제5권3호
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    • pp.60-70
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    • 2001
  • PCP추진제인 ADP-505추진제와 적합한 라이너의 연구를 수행하였다. 추진제로부터의 고에너지 가소제의 이동을 막기 위하여 라이너의 바인다는 HTPB/DDI계로 선정하였고, EPDM 인슐레이션/라이너, 추진제/라이너, EPDM 인슐레이션/라이너/추진제의 박리 시험을 통하여 라이너 조성을 연구하였고, 예비 선정된 라이너로 접착력인 인장, 전단, 박리(peel) 시험을 수행하였다. 시험 결과 추진제와 라이너간의 접착력은 박리값이 1.5∼l.8daN/cm, 인장력이 5.5∼6.0 bar, 전단력이 4.2∼5.0 bar로 우수한 편이다. 마찬가지로 인슬레이션/라이너/추진제간의 접착력도 박리력이1.8daN/cm, 인장력이 5.0∼6.0bar, 전단력이 4.5∼5.0bar로 우수한 편이다.

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수확 후 전처리에 의한 고랭지 배추 '춘광' 품종의 저온 저장 중 품질 변화에 대한 비교 (Comparison of the Quality of Highland-Grown Kimchi Cabbage 'Choon Gwang' during Cold Storage after Pretreatments)

  • 배상준;엄향란;김병섭;윤정로;홍세진
    • 원예과학기술지
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    • 제33권2호
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    • pp.233-241
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    • 2015
  • 강원도 강릉에 위치한 고랭지 지역에서 재배된 배추 '춘광' 품종은 수확 직후 차압식예냉, 통풍식예냉, 예건 처리를 하였고, 전처리 후 각각 처리에 대해 0.02mm HDPE film으로 liner 처리 유무에 따라 분류한 다음 $2^{\circ}C$에 저장을 하면서 품질 조사를 실시하였다. 저장 중 무게 손실은 liner 처리구에서 차압예냉이 3% 미만의 손실률을 보였고, 통풍예냉 또한 4% 미만의 손실률을 보였다. 그러나 liner 무처리 구에서는 통풍예냉이 10% 미만의 손실률을 보였고, 차압예냉의 경우 15% 이상으로 가장 많은 손실률을 보였으며, 오히려 대조구가 손실률이 가장 적었다. 가용성고형물의 경우 $2-4^{\circ}brix$ 정도로 나타났으며, 색도는 CIE $L^*$ 값은 50 내외로 큰 차이를 보이지 않았고, hue angle 값은 조금씩 감소하였으나 $120{\pm}2^{\circ}C$ 사이 녹색의 범위 안에 분포하여 색의 변화에 대한 차이는 없었다. Chroma 값의 경우에도 28-32 사이에 분포하였다. 경도는 22N 정도로 나타났으며, 처리에 따른 유의적 차이는 보이지 않았다. 관능 평과 결과, 외관과 아삭거림 정도의 경우 차압예냉을 실시한 후 liner를 적용한 배추에서 가장 좋은 결과가 나타났으며, 나머지 항목에서는 유의적 차이가 없었다. 저장 6주 경과 후 liner 무처리구에서 외관이 많이 손상되었고, 7주 경과 후 liner 처리구에서 통풍예냉과 예건에서 내부 갈변이 심하게 발생하였다.

복합차수층 조성기술을 이용한 폐기물매립지 바닥차수층 시공사례 (A Case Study of Bottom Liner Construction Using Composite Liner Technology in a Solid Waste Landfill)

  • 이규정;이남훈;박수영;전원표;이채영
    • 유기물자원화
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    • 제15권3호
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    • pp.90-96
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    • 2007
  • 폐기물 관리시설 중 하나인 폐기물매립지는 유해성분을 함유한 침출수와 가스로부터 발생되는 위생문제와 환경오염 방지를 위해 필요한 시설이며 이중에서 바닥차수층은 가스포집층과 더불어 반드시 설치되어져야 히는 공종이다. 매립된 폐기물에서 발생된 오염된 침출수는 지하수를 오염시키기 때문에 바닥치차수층은 내구성과 함께 $1{\times}10^{-7}cm/sec$ 이하의 저투수성을 확보해야만 한다. 본 고에서는 강원도 P군 폐기물 종합처리시설 중 "복합차수층 조성기술" 이 적용된 매립시설의 바닥차수층 공종과 관련하여 현장시공과정 상의 시험내용 및 품질관리 사항들을 요약, 정리하여 개발기술의 현장적용 사례를 소개하고자 한다.

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유한요소법에 의한 Corrugated Board의 휨 발란스 해석 (Buckling Analysis of Corrugated Board using Finite Element Method)

  • 박종민
    • Journal of Biosystems Engineering
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    • 제28권2호
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    • pp.127-136
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    • 2003
  • The top-to-bottom compression strength of corrugated board box is the most important mode of loading during it's no, and it depends largely on the edgewise compression strength of the corrugated board in the cross-machine direction and to a considerable extent on the flexural stiffness in both principal directions (CD; cross-machine direction, MD; machine direction) of the corrugated board. Corrugated board is a sandwich structure with an orthotropic property. The purpose of this study was to elucidate the principal design parameters for board combination of corrugated board from the viewpoint of bending strength through the finite element analysis [FEA] fur the various corrugated board. In general, the flexural stiffness [FS] in the MD was 2-3 times larger than that in the CD, and the effect of liner for the FS of corrugated board was much bigger than that of corrugating medium. The flexural stiffness index [FSI] was high when the stiffness of liner was in the order of inner, outer, and middle liner in double-wall corrugated board [DW], and the effect of the stiffness arrangement or itself reinforcement of corrugating medium on the FSI was not high. In single-wall corrugated board [SW] with DW. the variation of FSI with itself stiffness reinforcement of liner was much bigger than that with stiffness arrangement of liner. The highest FSI was at the ratio of about 2:1:2 for basis weight distribution of outer, middle, and inner liner if the stiffness of liner and total basis weight of corrugated board were equal in DW Secondarily. basis weight was in the order of inner, outer, and middle liner. However, the variation of FSI with basis weight distribution between liner and corrugating medium was much bigger than that with itself basis weight distribution ratio of liner and corrugating medium respectively in both DW and SW. md the FSI was high as more total basis weight was divided into liner. These phenomena fur board combination of corrugated board based on the FEA were well verified by experimental investigation.

Polystyrene 이장재가 아말감 변연부 미세누출에 미치는 영향 (THE EFFECT OF THE POLYSTYRENE LINER ON MICROLEAKAGE OF AMALGAM RESTORATION)

  • 이경선;노병덕;윤태철
    • Restorative Dentistry and Endodontics
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    • 제23권2호
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    • pp.586-596
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    • 1998
  • Amalgam is one of the most commonly used dental restoration material because of its convenience, economic and physical properties. But microleakage in the tooth and amalgam interface has been its major problem, and many efforts have been made to overcome this shortcoming. The purpose of this study is to compare the effect of various liners on microleakage of amalgam restoration. Cavities were prepared on the buccal or lingual surface of ninety sound, extracted human premolars and six different liners (Tubulitec$^{(R)}$, Superbond D-liner II Plus$^{(R)}$, Superbond D-liner II Plus$^{(R)}$ with polymer, Scotchbond Multipurpose Plus$^{(R)}$, Copalite$^{(R)}$, No liner) were unapplied according to manufacturer's instructions and amalgam had been condensed immediately. The specimens were thermocycled by dipping in methylene blue dye at $5^{\circ}C$ and $55^{\circ}C$ for 1500 cycles. The amalgam-tooth interface was examined under stereobinocular microscope and the dye penetration was scored. The results were as follows : 1. The Tubulitec$^{(R)}$ group showed less microleakage than no liner or Copalite$^{(R)}$ group (p<0.01). 2. The Tubulitec$^{(R)}$, Superbond D-liner II Plus$^{(R)}$, Superbond D-liner II Plus$^{(R)}$ with polymer and Scotch bond Multipurpose Plus$^{(R)}$ groups were not significantly different. 3. The Copalite$^{(R)}$ and Scotchbond Multipurpose Plus$^{(R)}$ groups were not significantly different. Using the polystyrene liner and resin liners under admixed type of high-copper amalgam restoration significantly reduced microleakage in the tooth-amalgam interface. Further clinical studies on polystyrene liner are recommended.

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폐기물매립지의 흙-벤토나이트 혼합차수층 특성에 관한 연구 (A Study on Soil-Bentonite Mixed Liner Properties for Waste Landfill)

  • 홍성길;한봉수;장연수
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2001년도 봄 학술발표회 논문집
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    • pp.597-604
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    • 2001
  • In this study, the engineering characteristics of soil-bentonite mixed liner are investigated using the laboratory hydraulic conductivity and strength tests. The soil used for the liner is clayey silt in the site and the weathered granitic soil located near the waste landfill studied. Mixing ratio of the bentonite which satisfies the requirement of hydraulic conductivity is determined and the optimum mixing ratio of betonite is recommended for the landfill. After the mixed liner is constructed, the block samples of the constructed liner are obtained and the properties of interest satisfy the requirements of the liner of the landfill.

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A STUDY ON THE ADHESION OF A SOFT LINER CONTAINING 4-META TO THE BASE METAL ALLOY AND ITS VISCOELASTIC PROPERTY

  • Park Hyun-Joo;Kim Chang-Whe;Kim Yung-Soo
    • 대한치과보철학회지
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    • 제41권6호
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    • pp.732-746
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    • 2003
  • Statement of problem. Soft lining materials, also referred to as tissue conditioning materials, tissue heating materials, relining materials, soft liners or tissue conditioners, were first introduced to dentistry by a plastic manufacturer in 1959. Since the introduction of the materials to the dental field, their material properties have been continually improved through the effort of many researchers. Soft lining materials have become widely accepted, particularly by prosthodontists, because of their numerous clinical advantages and ease of manipulation. Unfortunately, few reports have been issued upon the topic of increasing the bond strength between the base metal alloy used in cast denture bases and PMMA soft liner modified with 4-META, nor upon the pattern of debonding and material change in wet environment like a intra oral situation. Purpose. The purposes of this study were comparing the bond strength between base metal alloy used for the cast denture bases and PMMA soft liner modified with 4-META, and describing the pattern of debonding and material property change in wet environment like the intraoral situation. Material and Methods. This study consisted of four experiments: 1. The in vitro measurement of shear bond strength of the adhesive soft liner. 2. The in vitro measurement of shear bond strength of the adhesive soft liner after 2 weeks of aging. 3. A comparison of debonding patterns. 4. An evaluation the Relation time of modified soft liner. The soft liner used in this study was commercially available as Coe-soft (GC America.IL.,USA), which is provided in forms of powder and liquid. This is a PMMA soft liner commonly used in dental clinics. The metal primer used in this study was 4-META containing primer packed in Meta fast denture base resin (Sun Medical Co., Osaka, Japan). The specimens were formed in a single lap joint desist which is useful for evaluating the apparent shear bond strength of adhesively bonded metal plate by tensile loading. Using the $20{\times}20mm$ transparent grid, percent area of adhesive soft liner remaining on the shear area was calculated to classify the debonding patterns. To evaluate the change of the initial flow of the modified adhesive soft liner, the gelation time was measured with an oscillating rheometer (Haake RS150W/ TC50, Haake Co., Germany). It was a stress control and parallel plate type with the diameter of 35mm. Conclusion. Within the conditions and limitations of this study, the following conclusions were drawn as follows. 1. There was significant increase of bond strength in the 5% 4-META, 10% 4-META containing groups and in the primer coated groups versus the control group(P<0.05). 2. After 2 weeks of aging, no significant increase in bond strength was found except for the group containing 10% 4-META (P<0.05). 3. The gelation times of the modified soft liner were 9.3 minutes for the 5% 4-META containing liner and 11.5 minutes for the 10% 4-META liner. 4. The debonding patterns of the 4-META containing group after 2 weeks of aging were similar to those of immediaely after preparation, but the debonding pattern of the primer group showed more adhesive failure after 2 weeks of aging.

레이저 유도 형광법을 이용한 가솔린 엔진의 실린더 벽면에 존재하는 연료액막 가시화 (Measurement of Liquid Fuel Film on the Cylinder Liner in an SI Engine Using an LIF Technique)

  • 조훈;민경덕
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2001년도 춘계학술대회논문집D
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    • pp.25-30
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    • 2001
  • The liquid fuel film on the cylinder liner is believed to be a major source of engine-out hydrocarbon emissions in SI engines, especially during cold start and warm-up period. Quantifying the liquid fuel film on the cylinder liner is essential to understand the engine-out hydrocarbon emissions formation in SI engines. In this research, two-dimensional visualization was carried out to quantify liquid fuel film on the quartz liner in an SI engine test rig. The visualization was based on laser-induced fluorescence and total reflection. Using a quartz liner and a special lens, only the liquid fuel on the liner was visualized. The calibration technique was developed to quantify the fluorescence signal with the thickness gage and the calibration device. The fluorescence intensity increases linearly with increase in the fuel film thickness on the quartz liner. Using this technique, the distribution of the fuel film thickness on the cylinder liner was measured quantitatively for different valve lifts and injected fuel mass in the test rig.

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디젤엔진 실린더 라이너-피스톤 링의 코팅 층 강도에 따른 마모특성 연구 (Effect of Coating Layer Hardness on the Wear Characteristics of Diesel Engine Cylinder liner-Piston Ring)

  • 장정환;김정훈;김창희;문영훈
    • 소성∙가공
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    • 제17권5호
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    • pp.343-349
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    • 2008
  • The wear between piston ring face and cylinder liner is an extremely unpredictable and hard-to-reproduce phenomenon that significantly decreases engine performance. This study will discuss characteristics of wear between hard and soft piston ring coatings with running surface of cylinder liner. Detailed tribological analysis by using Pin-on-Disk(POD) testing machine describes the lubricity mechanism between piston ring coatings and cylinder liner at different temperature with and without oil. The effect of surface roughness of the cylinder liner on the friction coefficient and wear amount of piston ring coatings will also be analyzed. To simulate scuffing mechanism between piston ring and cylinder liner, accelerated lab testing was performed. This study will provide the data from tribological testing of hard and soft piston ring coatings against cylinder liner. Furthermore, the microstructures and morphological features of the surface and the near-surface materials during wear will be investigated. From the scuffing test by using POD testing machine, scuffing mechanisms for the soft and hard coating will be analyzed and experimentally confirmed.

매립지 차수재 두께 산정을 위한 컴퓨터 프로그램 개발 (Development of a Computer Program to Estimate Landfill Liner Thickness)

  • 도남영;이승래;정광영
    • 한국지반환경공학회 논문집
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    • 제6권4호
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    • pp.13-26
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    • 2005
  • 본 연구에서는 여러 연구자들에 의해 제안된 단일 점토 및 혼합 차수재를 통한 유기 및 무기 오염물질 이동에 관한 연구결과를 정리하여 보았고, 이러한 연구결과를 바탕으로 오염물질 유출 기준을 만족하는 차수재의 두께를 산정할 수 있는 차수재 설계 프로그램을 개발하였다. 본 프로그램을 이용하여 점토 차수재를 통한 $Cl^-$이온의 이동성에 바탕을 둔 매립지 두께를 산정해본 결과 비교적 합리적인 결과를 얻을 수 있었다. 따라서 본 연구에서 개발된 프로그램을 이용할 경우에는 비교적 간편한 방법으로 매립지 차수재의 예비설계를 수행할 수 있을 것으로 사료된다.

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