• 제목/요약/키워드: 몰딩

검색결과 117건 처리시간 0.022초

동력경운기 트레일러 바닥의 폴리스티렌 몰딩이 3차원진동에 미치는 영향 (3-Dimensional Accelerations by Mounting Polystyrene Material on Bottom of Power Tiller Trailer)

  • 이홍주;홍종호;이성범;김성엽
    • 한국농업기계학회:학술대회논문집
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    • 한국농업기계학회 2003년도 동계 학술대회 논문집
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    • pp.292-299
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    • 2003
  • 청과류는 수송과 취급기간 중에 충격, 마찰, 눌림, 타박 등에 지속적으로 노출된다. 그러므로 농산물의 품질을 저하시키는 물리적인 손상을 최소화하기 위해 최선의 처리와 수송방법을 선택할 필요가 있다. Hinsch 등(1993)에 의하면 충격흡수 시스템이 갖추어진 대형 냉동 트레일러에 체리, 복숭아, 배, 토마토를 수송하였을 때 3.5Hz에서 수직가속도가 가장 크게 나타났고 9-25Hz에서는 이보다는 약간 감소하였다 또한 6-18Hz에서는 트레일러의 모든 위치에서 수직가속도의 크기가 비슷하게 나타났고 3.5Hz에서만 트레일러의 앞쪽보다 뒤쪽에서 수직가속도가 적은 것으로 보고되어 다른 연구자들과는 상반된 결과를 보고하였다. (중략)

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마이크로/나노 계층구조 형성법 및 응용 (Fabrication of micro/nanoscale hierarchical structures and its application)

  • 정훈의;곽노균;이승석;서갑양
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2007년도 춘계학술대회A
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    • pp.426-428
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    • 2007
  • A simple method is presented for fabricating micro/nanoscale combined hierarchical structures using a two-step UV-assisted capillary molding technique. This lithographic method consists of two steps: (i) fabrication of partially cured polymer microstructures using a PDMS mold and (ii) subsequent nanofabrication using a high-resolution polyurethane acrylate (PUA) mold on top of the pre-formed microstructures. Using this technique, various micro/nano hierarchical structures were fabricated with minimum resolution down to 70 nm over a large area with very good reproducibility.

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전자선 조사된 에폭시 몰딩 컴파운드의 유전 특성 (Dielectric Characteristics of Epoxy Molding Compound irradiated with Electron Beam)

  • 홍능표;박우현;이성용;김대수;이수원;홍진웅
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1995년도 추계학술대회 논문집
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    • pp.289-292
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    • 1995
  • In this experiment the specimen is selected for epoxy resin used in the molding compound materials for the power semiconductors. The specimen was divided into the two parts. one is a specimen without irradiation, the other is irradiated with electron beam, of which dose is 1[Mrad], 2[Mrad], 4[Mrad], 8[Mrad] and 24[Mrad], respectively. From the analysis for the physical properties of the specimen, the carbonyl group which is asffact the electrical properties is decreased according to increase the dose of the electron beam. In the measurement of dielectric characteristics among the electrical properties, the frequency dependance of the dielectric characteristics is confirmed that its ${\beta}$-peak is represented by one peak due to attribute to the main chain below 50[$^{\circ}C$], and two peak above the temperature 100[$^{\circ}C$].

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에폭시수지로 몰딩된 권선의 열전달 특성 연구 (Analysis of Heat-transfer on Winding composed with Epoxy-resin)

  • 이현진;허창수;조한구;이기택;서유진
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2002년도 하계학술대회 논문집
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    • pp.402-405
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    • 2002
  • This paper presented the characteristic of Heat-transfer on the winding composed with Epoxy-resin in a 50 kVA cast-resin dry type transformer The resin cast transformer is used widely in supplying electricity systems. However, to know the thermal characteristics of that is very useful in designing, manufacturing, and maintaining, there is no pertinent method to calculate this. In this paper, Based on the results of the physical characteristics and the simulation by commercial software using FEM method, we established the Prototype Model for this. According to that Model, an analysis on a variation of the hottest spot temperature was discussed as a function of thermal conductivity for the individual windings composed with Epoxy-resin. The thermal conductivity of the individual windings with reference to upper way was discussed.

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전력용 반도체 몰딩재료의 체척고유저항에 미치는 전차선 조사의 영향 (The Effect of Electron Beam Irradiation for Volumn Resistivity in the Molding Compound for Power Semiconductor)

  • 이용우;흥능표;박우현;가출헌;이수원;홍진웅
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1995년도 추계학술대회 논문집 학회본부
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    • pp.370-372
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    • 1995
  • This paper mainly, describes the electrical characteristics caused by the change of structure in solid state of specimen by electron beam irradiation of high temperature-low expension type molding materials of power semiconductor element. The experiments on physical properties and electrical characteristics for the specimen irradiated electron beam are carried ont. For the investigation on physical properties, XRD analysis is used. And for the experiment of electrical characteristics, measurement of volumn resistivity is used.

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프레넬 렌즈 UV 미세복제 공정에서의 전사특성에 관한 연구 (Micro-replication quality of Fresnel Lens in UV micro-replication process)

  • 임지석;이남석;김석민;강신일
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 2005년도 추계학술대회 논문집
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    • pp.79-82
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    • 2005
  • Fresnel lens has number of applications in the optical systems because of its advantages. It is nearly flat lens that has small weight. It is conventionally used in lighthouse beacons, condensing unit of overhead projector and etc. Recently, demands of small size optical systems such as display units, information storage systems, optical detecting units had increased. Conventional manufacturing process of high quality Fresnel lens is direct machining. But it is not suitable for mass production because of high cost and long cycle time. Replication process is more suitable for mass production. But the Fresnel lens has number of sharp blade shape prism. In the replication process, this blade shape causes defects that can affect optical efficiency. In this study, replication process of blade shape pattern that has maximum height of $280{\mu}m$, aspect ratio 1.4 for Fresnel lens application.

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구조 세라믹스의 분말 성형 공정

  • 이해원;송휴섭;김주선;신현익;임건자;최인묵;문환;윤복규;전형우
    • 세라미스트
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    • 제4권3호
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    • pp.18-28
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    • 2001
  • 세라믹스 부품의 실형상 제조기술은 실형상 성형기술과 더불어 반응소결기술의 발달에 의하여 거의 수축율이 제로인 기술로 발달하고 있다. 분말사출성형으로 대표되던 실형상 성형기술도 젤 캐스팅과 열경화 몰딩과 같은 화학적 성형기술의 도입에 따라 플라스틱과 같이 쉽게 부품을 성형할 수 있는 상태에 도달하고 있다. 특히, 나노분말의 실형상 성형은 화학적 방법에 의해서만 가능할 것으로 예상된다.

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트랜스퍼 몰딩 방식을 이용한 고 색 균일성 특성을 가지는 백색 LED 램프 (Development of White LED Lamp Having High Color Uniformity With Transfer Molding Technology)

  • 유순재;김도형
    • 한국전기전자재료학회논문지
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    • 제23권1호
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    • pp.38-41
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    • 2010
  • Compared to conventional molding technology, the color uniformity of light direction emitted from LED is improved with PCB type lead frame technology in which metal thin film is used and transfer molding technology which makes the density of phosphor uniform by manufacturing high density LED lamp. The light efficiency and the color uniformity of the LED are improved by molding the phosphor layer outside of chip and controlling the thickness of the phosphor layer. CIE x,y difference of LED in major axis is also improved uniformly from 0 to 90 degrees.

마이크로 표면 구조물을 갖는 CMP 패드 제작 기술 개발 (Development of CMP Pad with Micro Structure on the Surface)

  • 최재영;정성일;박기현;정해도;박재홍;키노시타마사하루
    • 한국정밀공학회지
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    • 제21권5호
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    • pp.32-37
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    • 2004
  • Polishing processes are widely used in the glass, optical, die and semiconductor industries. Chemical Mechanical Polishing (CMP) especially is becoming one of the most important ULSI processes for the 0.25m generation and beyond. CMP is conventionally carried out using abrasive slurry and a polishing pad. But the surface of the pad has irregular pores, so there is non-uniformity of slurry flow and of contact area between wafer and the pad, and glazing occurs on the surface of the pad. This paper introduces the basic concept and fabrication technique of the next generation CMP pad using micro-molding method to obtain uniform protrusions and pores on the pad surface.

변성기의 몰딩 재료용 에폭시복합체의 열화 특성 (The Characteristics of Degradation in Epoxy Composites for Molding Materials of PT)

  • 박건호
    • 한국컴퓨터정보학회:학술대회논문집
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    • 한국컴퓨터정보학회 2011년도 제44차 하계학술발표논문집 19권2호
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    • pp.351-354
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    • 2011
  • The electrical degradation phenomena of epoxy composites to be used as a molding material for transformers were studied. The electrets were first manufactured by applying high voltages to five kinds of specimens given a mixing rate, and then TSC(Thermally Stimulated Current) values at the temperature range of $-160{\sim}200[^{\circ}C]$ were measured from a series of experiments. The behaviour of carrier and its origin in epoxy composites were examined, respectively. And various effects of electrical degradation on epoxy composites were also discussed in this study.

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