• 제목/요약/키워드: Multi-layered materials

검색결과 233건 처리시간 0.028초

지오컴포지트의 공정인자와 물성의 최적화 분석 (Optimization Analysis between Processing Parameters and Physical Properties of Geocomposites)

  • 전한용;김주용
    • 한국지반신소재학회논문집
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    • 제6권1호
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    • pp.39-43
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    • 2007
  • 열융착법을 이용하여 보강과 배수기능을 가진 니들펀치 및 스펀본딩 부직포의 지오컴포지트를 제조하였다. 이 다층 부직포의 물성(인장, 인열 및 파영강도, 투수도 등)은 열융착법을 사용하여 제조될 경우 온도, 압력, 접착시간 등의 공정인자에 좌우된다. 따라서, 열융착법으로 제조된 지오컴포지트의 공정인자와 물성의 최적화는 매우 중요하다. 본 연구에서는 인공신경망(ANN)을 사용하여 지오컴포지트의 제조공정 최적화를 위한 알고리즘이 개발되었다. 지오컴포지트의 공정인자를 변화시켜 부직포 성능변화를 예측하기 위한 신경망 모사가 적용되었으며, 분석결과에 대한 제조방법의 효과를 조사하였다.

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비대칭 스퍼터링에 의한 TiAIN/CrN 나노 다층 박막의 합성 및 특성 분석에 관한 연구 (Studies on the Development of TiAIN/CrN Multi-layered Thin Films by Unbalanced Magnetron Sputtering Process)

  • 김광석;김범석;이상율
    • 한국표면공학회지
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    • 제38권6호
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    • pp.207-211
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    • 2005
  • In this work a multi-layered nanostructured TiAIN/CrN superlattice coatings was synthesized using closed-field unbalanced magnetron sputtering method and the relationships between their superlattice period (1), micro-structure, hardness and elastic modulus were investigated. In addition, wear test at $500^{\circ}C$ and oxidation resistance test at $900^{\circ}C$ were performed to investigate high temperature properties of these thin films. The coatings were characterized in terms of microstructure and mechanical properties by transmission electron microscopy (TEM) and nano-indentation test. Results from TEM analysis showed that superlattice periods was inversely proportional to the jig rotation speed. The maximum hardness and elastic modulus of 37 GPa and 375 GPa were observed at superalttice period of 6.1 nm and 4.4 nm, respectively. An higher value of microhardness from TiAIN/CrN thin films than either TiAIN (30 GPa) or CrN (26 GPa) was noted while the elastic modulus was approximately an average of TiAIN and CrN films. These enhancement effects in superlattice films could be attributed to the resistance to dislocation glide across interface between the CrN and TiAIN layers. Much improved plastic deformation resistance ($H^3/E^2$) of 0.36 from TiAIN/CrN coatings was observed, compared with 0.15 and 0.16 from TiAIN and CrN, respectively. Also the wear resistance at $500^{\circ}C$ was largely increased than those of single TiAIN and CrN coatings and TiAIN/CrN coatings showed much reduced weight gain after exposure at $900^{\circ}C$ for 20 hours.

DC, RF Magnetron Sputtering 공법을 이용한 다층 $TiO_2/Al/TiO_2$, $TiO_2/Cr/TiO_2$ 진주안료용 필름의 광학적 특성 (The Optical Properties of $TiO_2/Al/TiO_2$, $TiO_2/Cr/TiO_2$ Multi-layered Pearl-pigment films by DC, RF Magnetron Sputtering)

  • 이남일;장건익;정재일;조성윤;장길완
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2006년도 하계학술대회 논문집 Vol.7
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    • pp.448-449
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    • 2006
  • For the possible applicative pearl pigment, multi-layered $TiO_2/Al/TiO_2$, $TiO_2/Cr/TiO_2$ thin film was deposited on glass substrate by using sputtering method. $TiO_2$ and Al or Cr was selected as a possible high and low refraction materials at the film interface respectively. Optical properties including color effect were systematically studied in terms of different film thickness and film layers by using spectrometer. In order to expect the experimental results, the simulation program, the Essential Macleod Program(EMP) was adopted and compared with the experimental data. The film consisting of $TiO_2/Al/TiO_2$, $TiO_2/Cr/TiO_2$ layers show the wavelength range of 430 - 760nm, typically color ranges between bluish purple and red. It was confirmed that this experimental result was quite well matched with the experimental one.

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폐플라스틱의 재활용에 관한 연구 (Studies on Recycling Technology Wasted Plastic)

  • 이수근
    • 한국포장학회지
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    • 제11권1호
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    • pp.47-52
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    • 2005
  • The wasted plastic PC/ABS retainer, polyurethane foam (PUF) and vinyl (PVC) skin. In order to investigate the recycling process, the multi-layered instrument panel Each of materials separated was shredded and crushed to create many small particles respectively. The separation of the foam and skin and retainer of zigzagged air blower. Pilot tests performed at the equipment yielded 98.8% by weight of the available PVC and 99.3% by weight of the available PC/ABS respectively. Secondly, the thermal stabilizer and the compatabilizer have been used to improve the physical propertied of recycled materials.. The properties of recycled PVC materials resulted in about 50% compared to that of virgin materials after treatment by Pb-St thermal stabilizer. In addition, the properties of recycled PC/ABS materials was also obtained about 80% compared to that of virgn materials after treatment by PMMA compatabilizer.

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High Efficiency AMOLED Using Hybrid of Small Molecule and Polymer Materials Patterned by Laser Transfer

  • Chin, Byung-Doo;Suh, Min-Chul;Kim, Mu-Hyun;Kang, Tae-Min;Yang, Nam-Choul;Song, Myung-Won;Lee, Seong-Taek;Kwon, Jang-Hyuk;Chung, Ho-Kyoon;Wolk, Martin B.;Bellmann, Erika;Baetzold, John P.
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2003년도 International Meeting on Information Display
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    • pp.163-166
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    • 2003
  • Laser-Induced Thermal Imaging (LITI) is a laser addressed patterning process and has unique advantages, such as high-resolution patterning with over-all position accuracy of the imaged stripes within 2.5 micrometer and scalability to large-size mother glass. This accuracy is accomplished using real-time error correction and a high -resolution stage control system that includes laser interferometers. Here the new concept of mixed hybrid system which complement the advantages of small molecular and polymeric materials for use as an OLED; our system can realize the easy processing of polymers and high luminance efficiency of recently developed small molecules. LITI process enables to pattern the stripes with excellent thickness uniformity and multi-stacking of various functional layers without using any type of fine metal shadow mask. In this study, we report a full-color hybrid OLED using the multi-layered structure of small molecular/polymeric species.

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9mm 권총탄 위협을 받는 적층구조의 방탄성능 연구 (Study on Bullet-Proof Performance of Multi-Layered Hybrid Armor Against 9mm FMJ Projectile)

  • 이종구;김시호;김건인;조맹효
    • 한국전산구조공학회논문집
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    • 제25권6호
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    • pp.487-495
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    • 2012
  • 고속의 탄을 방호하기 위해 전통적으로 알루미늄 합금, RHA(Rolled Homogeneous Armour) 강과 같이 인장 및 압축 강도가 큰 금속이 주로 방탄재료로 사용되었다. 이런 전통적인 방탄재료는 우수한 방탄성능을 가지는 반면, 면 밀도가 커서 방탄 장갑의 무게를 증가시키는 요인이 된다. 때문에 작은 면 밀도를 가질 뿐만 아니라 큰 비강도를 가지는 마그네슘합금이 전통적인 방탄재료의 대체제로 평가받고 있다. 하지만 전통적인 방탄재료에 비해 마그네슘합금의 공간 효율이 떨어져 장갑의 두께 혹은 부피를 증가시키는 요인이 된다. 본 연구에서는 마그네슘합금의 공간 효율의 개선을 위해 마그네슘합금 단일물질이 아닌 세라믹(Ceramic), 마그네슘합금(Mg alloy), 케블라(Kevlar)를 순서대로 적층한 하이브리드 장갑모델을 선정하였고, 9mm FMJ(Full Metal Jarket) 탄 위협에 대한 방탄해석을 통해 하이브리드 장갑이 방탄성능 척도인 면밀도를 감소시킬 뿐만 아니라 공간효율도 개선시킴을 보였다.

Propagation of non-uniformly modulated evolutionary random waves in a stratified viscoelastic solid

  • Gao, Q.;Howson, W.P.;Watson, A.;Lin, J.H.
    • Structural Engineering and Mechanics
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    • 제24권2호
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    • pp.213-225
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    • 2006
  • The propagation of non-uniformly modulated, evolutionary random waves in viscoelastic, transversely isotropic, stratified materials is investigated. The theory is developed in the context of a multi-layered soil medium overlying bedrock, where the material properties of the bedrock are considered to be much stiffer than those of the soil and the power spectral density of the random excitation is assumed to be known at the bedrock. The governing differential equations are first derived in the frequency/wave-number domain so that the displacement response of the ground may be computed. The eigen-solution expansion method is then used to solve for the responses of the layers. This utilizes the precise integration method, in combination with the extended Wittrick-Williams algorithm, to obtain all the eigen-solutions of the ordinary differential equation. The recently developed pseudo-excitation method for structural random vibration is then used to determine the solution of the layered soil responses.

『동의보감』 심장도(心臟圖)의 묘사 특징과 그 기원에 대한 연구 (A Study on the Descriptive Features and Origin of the Heart Diagram in the Donguibogam(東醫寶鑑))

  • 조학준
    • 대한한의학원전학회지
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    • 제36권1호
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    • pp.17-32
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    • 2023
  • Objectives : This paper investigates the background, meaning and origin of the descriptions of the Heart such as 'seven orifices', 'sanmao', 'saw-toothed four layered lines' that are unique to the diagram in the Donguibogam. Methods : First the Heart diagram of the Donguibogam was compared with other Zhangfu diagrams of the past. Materials related to unique features in the descriptions of the Heart in the Donguibogam were collected, against which descriptive features were analyzed. Results : Of the many unique features, the descriptive basis of the 'seven orifices' could be found in the Qixingban[七星板] as a physical entity reflecting basic anatomical knowledge. The 'sanmao', which is compared to the Santaixing[三台星], could be understood as a non-physical entity whose descriptive basis could be found in the Xinxuetu of the Xinching. It could be assumed that the 'saw-toothed four layered lines' are likened to the multi-layered petals or calyx of a lotus flower bud to describe the Pericardium, or to the multiple walls of a mountain fortress surrounding a palace to describe the Danzhong, which is the chest cavity. These features could be understood as results of spiritualism influence. Conclusions : It could be concluded that Heo Jun, in his attempt to describe the Heart in more detail than previous diagrams of the Zangfu, referenced popular texts and images based on anatomical knowledge of previous texts, added varied descriptions resulting in a new diagram with a completely different origin.

DSSC광전극의 나노구조 제어 및 투명전극 소재 개발

  • 장현석
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2009년도 제38회 동계학술대회 초록집
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    • pp.28-28
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    • 2010
  • Photoelectrochemical solar cells such as dye-sensitized cells (DSSCs), which exhibit high performance and are cost-effective, provide an alternative to conventional p-n junction photovoltaic devices. However, the efficiency of such cells plateaus at 11-12%, in contrast to their theoretical value of 33%. Improvements in efficiency can only occur through a fundamental understanding of the underlying physics, materials, and device designs of DSSCs. A photoelectrode consisting of semiconducting oxide nanoparticles and a transparent conducting oxide electrode (TCO) is a key component of DSSC and design of photoelectrode materials is one of promising strategies to improving energy conversion efficiency. We introduce monodisperesed $TiO_2$ nanoparticles prepared by forced hydrolysis method and their superiority as photoelectrode materials was characterized with aids of optical and electrochemical analysis. Multi-layered TCO materials are also introduced and their feasibility for use as photoelectrodes is discussed in terms of optical absorption and charge collecting properties.

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