• 제목/요약/키워드: gap filling

검색결과 183건 처리시간 0.028초

Electronic structure of potassium-doped copper phthalocyanine studied by photoemission spectroscopy and density functional calculations

  • 임영지;김종훈;지동현;조상완
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2016년도 제50회 동계 정기학술대회 초록집
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    • pp.142.2-142.2
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    • 2016
  • The metal intercalation to an organic semiconductor is of importance since the charge transfer between a metal and an organic semiconductor can induce the highly enhanced conductivity for achieving efficient organic electronic devices. In this regard, the changes of the electronic structure of copper phthalocyanine (CuPc) caused by the intercalation of potassium are studied by ultraviolet photoemission spectroscopy (UPS) and density functional theory (DFT) calculations. Potassium intercalation leads to the appearance of an intercalation-induced peak between the highest molecular occupied orbital (HOMO) and the lowest molecular unoccupied orbital (LUMO) in the valence-band spectra obtained using UPS. The DFT calculations show that the new gap state is attributed to filling the LUMO+1, unlike a common belief of filling the LUMO. However, the LUMO+1 is not conductive because the ${\pi}$-conjugated macrocyclic isoindole rings on the molecule do not make a contribution to the LUMO+1. This is the origin of a metal-insulator transition through heavily potassium doped CuPc.

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대전입자층과 충전비율이 구동에 미치는 영향 (Effects of Layers and Filling Fraction on Driving Properties)

  • 김진선;김영조
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2010년도 하계학술대회 논문집
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    • pp.32-32
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    • 2010
  • 본 논문에서는 대전입자층과 충전비율에 따른 구동특성을 평가하였다. 소자 제작은 동일한 cell gap에 대전입자의 입자층과 충전비율을 다르게 하여 패널에 주입하였으며 문턱전압 및 구동전압에서의 구간에서 실제로 움직이는 대전입자의 구동입자 개수와 면적을 측정하였다. 그 결과 대전입자층 및 충전비율에 따라서 구동전압 및 구동입자수와 white, black의 차지하는 면적비율의 차이가 있었으며, 면적측정으로 contrast ratio를 평가하고 실제로 구동하는 입자의 비율을 확인하였다.

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이중튜브의 액압 성형특성 연구 (Hydroforming Characteristics of Double Layered Tube)

  • 권승오;이혜경;정기석;문영훈
    • 소성∙가공
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    • 제16권8호
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    • pp.567-574
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    • 2007
  • Double layered tube is assembled with an inner tube and an outer tube, similar in material or not, contacting closely and deforming simultaneously when subjected to external force. For the manufacturing of double layered tube, the hydroforming assembly technology has several advantages. Therefore in this study, hydroforming characteristics of double layered tube was investigated. The free bulge test was performed to produce formability diagrams of double layered tubes at various forming pressure and feeding amounts. The hexagonal shape hydroforming test was also performed to estimate the dimensional accuracies of double layered tube through the corner filling ratio and the gap between inner and outer tube. Besides experimental analyses, the analytical model that can predict internal pressure for the hydroforming of double-layered tube was proposed and experimentally validated.

BOTDA based water-filling and preloading test of spiral case structure

  • Cui, Heliang;Zhang, Dan;Shi, Bin;Peng, Shusheng
    • Smart Structures and Systems
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    • 제21권1호
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    • pp.27-35
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    • 2018
  • In the water-filling and preloading test, the sensing cables were installed on the surface of steel spiral case and in the surrounding concrete to monitor the strain distribution of several cross-sections by using Brillouin Optical Time Domain Analysis (BOTDA), a kind of distributed optical fiber sensing (DOFS) technology. The average hoop strain of the spiral case was about $330{\mu}{\varepsilon}$ and $590{\mu}{\varepsilon}$ when the water-filling pressure in the spiral case was 2.6 MPa and 4.1 MPa. The difference between the measured and the calculated strain was only about $50{\mu}{\varepsilon}$. It was the first time that the stress adjustment of the spiral case was monitored by the sensing cable when the pressure was increased to 1 MPa and the residual strain of $20{\mu}{\varepsilon}$ was obtained after preloading. Meanwhile, the shrinkage of $70{\sim}100{\mu}{\varepsilon}$ of the surrounding concrete was effectively monitored during the depressurization. It is estimated that the width of the gap between the steel spiral case and the surrounding concrete was 0.51 ~ 0.75 mm. BOTDA based distributed optical fiber sensing technology can obtain continuous strain of the structure and it is more reliable than traditional point sensor. The strain distribution obtained by BOTDA provides strong support for the design and optimization of the spiral case structure.

"Ring 생산 Control System의 퍼지 적응제어" (An adaptive fuzzy control for closed-die ring-rolling process)

  • 이용현
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1996년도 한국자동제어학술회의논문집(국내학술편); 포항공과대학교, 포항; 24-26 Oct. 1996
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    • pp.1476-1479
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    • 1996
  • 발전설비나 자동차 그리고 항공우주분야에 사용되는 각종 bearing, 원형부품들에 사용되는 ring을 생산하는 방법중, 가장 효과적이고 경제적인 방법은 ring rolling (ring 압연)이다. 이 방법은 직경 50cm에서 2m이상의 원형 ring을 연속적으로 짧은 시간내에 (한 ring당 약 1분) 생산 가능하다. 이제까지의 수학적 모델을 사용한 제어시스템은 ring의 단면적이 사각형인 제품에는 최소한의 오차로 생산 가능하였으나, plant의 생산성과 제품의 다양성을 위하여 ring의 단면적이 복잡한 것을 생산시에는 문제점이 노출되었다. 왜냐하면 기존의 수학적모델이 roll gap 또는 metal forming zone에 근거하여 modelling하였기 때문이다. 본 논문에서는, 이러한 문제점을 고전적인 수학적 모델을 기초로한 adaptive control system의 방법대신에, 축적된 control system설계와 운용 경험을 이용하여 설계한 퍼지제어기 및 그것의 실적용 그리고 그 결과를 소개한다. 실적용 결과는, 제조된 단면적이 상대적으로 복잡한 bearing의 형상이 (filling grad)이 제어기의 제어정도 판단기준이었는데, 99.5%의 형상도를 보임으로서 industry에서 요구하는 제품기준을 만족시켰다. 또한 짧은 제어기 설계 및 on-line optimization 기간 또한 이 제어기의 장점이었다.

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근관충전방법에 따른 폐쇄효과의 비교 (COMPARISON OF THE SEALING ABILITY OF VARIOUS ROOT CANAL FILLING TECHNIQUES)

  • 이동경;윤수한;배광식
    • Restorative Dentistry and Endodontics
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    • 제23권1호
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    • pp.346-356
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    • 1998
  • The purpose of this study was to evaluate the sealing ability of various canal filling methods. Palatal roots of ninety extracted human maxillary molar teeth were resected at cementoenamel junction. Eighty of them were randomly assigned to four experimental groups, ten were served as positive and negative controls. All canals were prepared to # 40 using Profile. Experimental groups were obturated by lateral condensation technique, Thermafil technique, Continuous Wave of Condensation Technique, and down-pack & back-fill technique of Obtura-II, each with root canal sealer. Control groups were not obturated. Teeth were immersed in resorcinol-formaldehyde resin for 5 days at $4^{\circ}C$, and the resin was allowed to polymerize completely for 4 days at room temperature. Teeth were then ground horizontally at 1.5mm(level 1), 2.5mm(level 2), 3.5 mm(level 3) from the anatomical apex and examined with a stereomicroscope at ${\times}40$ magnification. The gap between the canal wall and the filling material, which was filled with the resin, was measured at each of the three levels. Each ratio of leakage was obtained by calculating the ratio of the area of the resin to the total area of the canal and was analyzed statistically (Rank-sum test). The results were as follows : 1. At the level 1, there was the greatest leakage in the Thermafil group and Obtura-II group, and the difference between the Obtura-II group and Continuous Wave of Condensation Technique group was statistically significant(p<0.05). 2. At the level 2, there was the least leakage in the Continuous Wave of Condensation Technique group, but there was no statistically significant difference between each group (p>0.05). 3. At the level 3, there was no statistically significant difference between each group(p>0.05).

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Room Temperature Chemical Vapor Deposition for Fabrication of Titania Inverse Opals: Fabrication, Morphology Analysis and Optical Characterization

  • Moon, Jun-Hyuk;Cho, Young-Sang;Yang, Seung-Man
    • Bulletin of the Korean Chemical Society
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    • 제30권10호
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    • pp.2245-2248
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    • 2009
  • This paper demonstrates room temperature chemical vapor deposition (RTCVD) for fabricating titania inverse opals. The colloidal crystals of monodisperse polymer latex spheres were used as a sacrificial template. Titania was deposited into the interstices between the colloidal spheres by altermate exposures to water and titanium tetrachloride (Ti$Cl_4$) vapors. The deposition was achieved under atmospheric pressure and at room temperature. Titania inverse opals were obtained by burning out the colloidal template at high temperatures. The filling fraction of titania was controlled by the number of deposition of Ti$Cl_4$ vapor. The morphology of inverse opals of titania were investigated. The optical reflection spectra revealed a photonic band gap and was used to estimate the refractive index of titania.

13mm 크기 순환굵은골재 치환이 콘크리트의 공학적 특성에 미치는 영향 (Effect of Replacement of Recycled Coarse Aggregate with 13mm on Engineering Properties of the Concrete)

  • 강병회;자오양;박재용;조만기;한민철;한천구
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2014년도 추계 학술논문 발표대회
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    • pp.137-138
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    • 2014
  • The aim of this research is suggesting the method of obtaining well-graded aggregates for concrete replacing the recycled aggregate which size range is from 5 to 13 mm to currently used gap-graded natural aggregates which size range is only 13 to 25 mm. according to the tests results, the workability of concrete was improved with replacing the aggregates of 5 to 13 mm of size range because of compensating gap-grading. Furthermore, there was an improvement in compressive strength when the aggregates of 5 to 13 mm of size range was replaced because obtained well-graded aggregates contributed on increasing adhesiveness and filling internal pore system. Comparing replacing recycled aggregate to natural aggregate, there was no significant difference on the performances.

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Mechanism Study of Flowable Oxide Process for Sur-100nm Shallow Trench Isolation

  • Kim, Dae-Kyoung;Jang, Hae-Gyu;Lee, Hun;In, Ki-Chul;Choi, Doo-Hwan;Chae, Hee-Yeop
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2011년도 제40회 동계학술대회 초록집
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    • pp.68-68
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    • 2011
  • As feature size is smaller, new technology are needed in semiconductor factory such as gap-fill technology for sub 100nm, development of ALD equipment for Cu barrier/seed, oxide trench etcher technology for 25 nm and beyond, development of high throughput Cu CMP equipment for 30nm and development of poly etcher for 25 nm and so on. We are focus on gap-fill technology for sub-30nm. There are many problems, which are leaning, over-hang, void, micro-pore, delaminate, thickness limitation, squeeze-in, squeeze-out and thinning phenomenon in sub-30 nm gap fill. New gap-fill processes, which are viscous oxide-SOD (spin on dielectric), O3-TEOS, NF3 Based HDP and Flowable oxide have been attempting to overcome these problems. Some groups investigated SOD process. Because gap-fill performance of SOD is best and process parameter is simple. Nevertheless these advantages, SOD processes have some problems. First, material cost is high. Second, density of SOD is too low. Therefore annealing and curing process certainly necessary to get hard density film. On the other hand, film density by Flowable oxide process is higher than film density by SOD process. Therefore, we are focus on Flowable oxide. In this work, dielectric film were deposited by PECVD with TSA(Trisilylamine - N(SiH3)3) and NH3. To get flow-ability, the effect of plasma treatment was investigated as function of O2 plasma power. QMS (quadruple mass spectrometry) and FTIR was used to analysis mechanism. Gap-filling performance and flow ability was confirmed by various patterns.

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국제물품매매계약(國際物品賣買契約)에서 'Liquidated Damage Clause'(LD 조항(條項))의 유효성(有效性)과 실무적(實務的) 적용(適用)에 관한 연구 (A Study on the Validity and Practical Application of Liquidated Damage Clause(LD Clause) in International Sales Contract)

  • 오원석
    • 무역상무연구
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    • 제17권
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    • pp.71-91
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    • 2002
  • The purpose of this paper is to examine the viewpoints of the different legal systems for the validity of LD Clause and the possibility of gap-filling function of UNIDROIT Principles in International Sales Contract. The results of comparative study between common law system and civil law system, and between CISG and UNCDROIT Principles is as follows: First, common law system distinguishes LD Clause and Penalty Clause, but civil law system including Korean law does not strictly distinguish the difference between them, provided that the liquidated damages are not grossly excessive. Second, CISG does not concerned with the validity of LD Clause but entrust this matter to the law applicable by virtue of the rules of private international law; conversely the Principles follow similar position of civil law system. The possibility of gap-filling of the Principles is more positive in the case of arbitration than in the case of litigation. On the basis of above study, I also checked the LD Clauses of ICC Model International Sales and the Model Contracts of Korean Commercial Arbitration Board. The LD Clauses of there two Model Contract seem very appropriate and reasonable for the reference in practical application. The appropriate, not excessive, LD Clause will contribute not only to eliminate the burden of proof for the actual damages, but also to enforce both parties to perform their obligations in their contracts. Therefore, When we make contract, we should keep in our mind to insert the reasonable and appropriate LD Clause in the sales contract. If not, so to speak, litigated damages are grossly excessive, the Clause may be invalid in some legal system.

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