• Title/Summary/Keyword: CF

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Genre-based Collaborative Filtering Movie Recommendation (장르 기반 Collaborative Filtering 영화 추천)

  • Hwang, Ki-Tae
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.10 no.3
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    • pp.51-59
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    • 2010
  • There have been proposed several movie recommendation algorithms based on Collaborative Filtering(CF). CF decides neighbors whose ratings are the most similar to each other and it predicts how well users will like new movies, based on ratings from neighbors. This paper proposes a new method to improve the result predicted by CF based on genres of the movies seen by users. The proposed method can be combined to the most of all existing CF algorithms. In this paper, a performance evaluation has been conducted between an existing simple CF algorithm and CF-Genre that is the proposed genre-based method added to the CF algorithm. The result shows that CF-Genre improves 3.3% in prediction performance over existing CF algorithms.

그리드를 이용한 플라즈마 변수 제어에 따른 Ar/CF4 플라즈마에서 중성종 및 이온들의 분포 변화

  • 홍정인;배근희;서상훈;장흥영
    • Proceedings of the Korean Vacuum Society Conference
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    • 1999.07a
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    • pp.210-210
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    • 1999
  • 그리드 전압을 +20V에서 -20V까지 변화시켜 줌을 이용해 확산 영역의 전자의 온도를 2-0.6eV까지 제어할 수 있었으며, 전자 밀도는 1010cm-3 - 1011cm-3, 플라즈마 전위는 3-25V까지 제어할 수 있었다. <그림1>은 실험결과이다. 그 외 전자의 온도는 입력 전력의 주파수 및 크기에는 거의 무관하나 압력에 반비례하였으며, 밀도는 전력의 크기에 비례하고, 압력에 반비례하나, 전력의 주파수에는 무관하였다. 그리드 전압이 20V에서 -20V로 변함에 따라 전자의 온도가 떨어져 높은 에너지를 가진 전자들이 줄어들게 되어 CF3+의 양은 많아지고 CF2+와 CF+의 양은 상대적으로 줄어들어 CF3+와 CF2+ 비는 4-18 CF3+와 CF+ 비는 2-5까지 변화하였으며, 변화모양은 전자 온도에 크게 의존하였다. <그림2>는 결과를 나타낸 것이다. 그 외 CF3+ / CF2+ 와 CF3+ / CF+는 입력 전력의 크기에 반비례하며, 압력, 가스 주입량에 따라서도 이온들의 분포 변하였다. 그러나 입력 전력의 주파수와는 무관하였다. Appearance mass spectrometry를 이용한 결과 CF, CF 중성종의 분포도 그리드 전압에 따라 변하여 그리드 전압이 높은 경우 더 많이 존재하였다.

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Properties of Conductive Polymer Composite Films Fabricated under High Intensity Electric Fields : Effect of CF Sizing Treatment (고전기장을 이용한 전도성 고분자 복합필름의 제조 및 특성 연구 : 탄소섬유 Sizing처리가 탄소섬유/폴리에틸렌 필름의 특성에 미치는 영향)

  • 고현협;김중현;임순호;김준경;최철림
    • Polymer(Korea)
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    • v.25 no.2
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    • pp.293-301
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    • 2001
  • Electrically conductive carbon fiber/high density polyethylene (CF/HDPE) composite films were fabricated by new method, so called electron-ion technology (EIT) and the effects of CF epoxy sizing on the volumetric resistivity. tensile strength and interphase properties of the films were investigated. While epoxy sizing increased conductivity of composite films resulting from enhanced tunneling effect it reduced interphase adhesion between CF and HDPE because polar epoxy sizing and nonpolar HDPE are incompatible. Consequently epoxy sized CF(CF(S)) caused significant reduction in the volumetric resisitivity and tensile strength of composite films when compared with unsized CF(CF(U)). Epoxy sizing reduced nucleating efficiency of CF(S), therefore CF(S)/HDPE composite films showed nonuniform transcrystalline layer when compared with CF(U)/HDPE composite films.

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The Study of the Implementation of the Boot System Using CF(Compact Flash) memory card 2. Implementation of the Boot Loader (CF(Compact Flash)메모리 카드를 이용한 부트 시스템 구현에 관한 연구 2. 부트로더의 구현)

  • 이광철;김영길
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.8 no.1
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    • pp.115-122
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    • 2004
  • This paper describe the implementation or the boot loader for the boot system using of memory card. This boot roader consist of the system initialization, CF card checking, CF memory card checking, file system and the program relocator. This boot loader increase the system stability with program consistency checking algorithm in the read phase from the CF memory card. And this system have the compatibility in CF memory card file system, so system manufacturing productivity increase.

Occurrence of Leaf Mold Pathogen Fulvia fulva Isolates Infecting Tomato Cf-9 Cultivars in Korea (토마토 Cf-9 저항성 품종에 잎곰팡이병을 일으키는 Fulvia fulva 균주의 국내 발생)

  • Lee, Ji Hyun;Park, Myung Soo;Kim, Jin-Cheol;Jang, Kyoung Soo;Choi, Yong Ho;Kim, Heung Tae;Choi, Gyung Ja
    • Horticultural Science & Technology
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    • v.31 no.6
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    • pp.740-747
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    • 2013
  • Leaf mold symptoms were found on commercial tomato cultivars carrying the Cf-9, a resistance gene to leaf mold pathogen Fulvia fulva in 2012 at Buyeo, Chungnam in Korea. Fifteen-fungal isolates were obtained from four Cf-9 cultivars of tomato including 'Cutie', 'otaerangdia', 'Unicorn' and 'Rapito'. Due to their same morphological appearances and colony color, nine isolates were selected and identified as F. fulva based on molecular analysis of the internal transcribed spacer rDNA sequence. Pathogenicity of the 15 isolates on five commercial cultivars carrying Cf-4, Cf-5, and Cf-9 were tested. All the isolates showed strong pathogenicity on Cf-9 cultivars, 'Cutie' and 'Dotaerangdia', and Cf-5 cultivar, 'Yoyocaptain'. In contrast, on Cf-4 cultivar, 'Superdotaerang', five isolates were virulent and the other isolates were not. In addition, two fungal isolates, infecting Cf-9 cultivar and non-infecting Cf-4 cultivar, were selected and their pathogenicity was tested on 17 commercial cultivars reported as tomato having Cf-9 resistance gene. Among them, 15 cultivars were susceptible and 2 cultivars were resistant. It is likely that the two cultivars include other resistance gene. To our knowledge, this is the first report on the occurrence of Cf-9 infecting F. fulfva strains in Korea.

A study on the behavior of CF, CF2 radicals in an inductively coupled plasma using Laser Induced Fluorescence (레이저 유도 형광법을 이용한 유도 결합 플라즈마내의 CF, CF2 라디칼의 거동에 관한 연구)

  • 김정훈;이호준;황기웅;주정훈
    • Journal of the Korean Vacuum Society
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    • v.9 no.1
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    • pp.76-80
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    • 2000
  • CF & $CF_2$ radicals in a $C_4F_8$ inductively coupled plasma were observed with laser induced fluorescence. 251.9nm UV laser was used for the $CF_2$ excitation and 265.3nm UV emitted light for the detection which has the maximum intensity among many induced fluorescence lights. In the case of CF radical detection, 232.9nm UV laser was used for the excitation and 247.6nm for the detection. $CF_2$ radical density increased toward substrate, while CF radical had its maximum at about 10nm away from the substrate. The atomic fluorine density which was studied by the actinometry increased as the position moves away from the substrate. This phenomena was thought to have a close relation with the polymer growth on the wafer. When the bias voltage increased, $CF_2$ , CF radicals decreased while the atomic fluorine increased tio some extent and then decreased, which was thought to be due to the change in the ionization and dissociation.

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Behaviors of Atomic Fluorine and Fluorocarbon Radicals in $CF_4+H_2$Electron Cyclotron Resonance Plasma Employing Actinometry and Appearance Mass Spectrometry (전자 회전 공명 플라즈마 발생 장치에서의 $CF_4+H_2$가스 방전시 Appearance Mass Spectrometry와 Actinometry를 통한 플루오로카본 래디칼과 플루오린 원자의 거동에 관한 연구)

  • 도현호;김정훈;이석현;황기웅
    • Journal of the Korean Vacuum Society
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    • v.4 no.4
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    • pp.417-424
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    • 1995
  • 전자 회전 공명 플라즈마 발생 장치에서 CF4를 방전시켰을 때 각종 플루오로카본 래디칼의 절대적, 상대적 밀도 변화를 수소 철가율, 동작 압력 그리고 축방향에 따라 appearace mass spectrometry(AMS)를 통해 조사하였으며, 플루오린 원자의 상대적 밀도 변화가 actinometry법에 의해 조사되었다. 수소첨가에 따른 CF2 래디칼의 거동을 actinometry와 AMS로 살펴보았을 때 서로 일치하는 경향을 얻었으며 마이크로웨이브전력 500W, 압력 7.5mTorr에서 CF3와 CF2 래디칼의 밀도가 CF에 비해 높았으며 각각 2X1013/㎤, 1X1013/㎤의 값을 가졌다. 수소를 첨가함에 따라 플루오린 원자와 CF3의 밀도는 감소하는 반면 CF2와 CF의 밀도는 현저히 증가하여 수소가 40% 첨가된 경우 CF2의 밀도가 CF3보다 커짐을 확인하였다. 또한, CF2가 증가하면서 C2F4의 존재가 확인되었으며, 수소가 30% 첨가된 경우 축방향을 따라 C2F4래디캄만이 증가하였고 플루오린 원자는 감소하는 반면 다른 CFx(x=1~3)래디칼은 거의 변화가 없었다. 이러한 실험 결과를 토대로 CF4+H2 플라즈마를 이용한 산화막 식각 특성이 설명되었다.

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Characterization of Choristoneura fumiferana Genes of the Sixth Subunit of the Origin Recognition Complex: CfORC6

  • Wang, Xaiochun;Carstens, Eric B.;Feng, Qili
    • BMB Reports
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    • v.39 no.6
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    • pp.782-787
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    • 2006
  • A new protein was cloned and identified as the sixth subunit of Choristoneura fumiferana origin recognition complex (CfORC6). The newly identified 43 kDa protein CfORC6 is much bigger than DmORC6 (25.7 kDa) and HsORC6 (28.1 kDa), though it's 23.85% identical to DmORC6 and 23.81% identical to HsORC6. Although the molecular weight of CfORC6 is close to ScORc6 (50 kDa), CfORC6 is only 14.03% identical to ScORC6. By alignment, it was found that the N-terminal of CfORC6 has about 30% identities with other ORC6s, but about 100aa of C-terminal of CfORC6 has no identity with other ORC6s. Like ScORC6, CfORC6 has many potential phosphorylation sites, (S/T)PXK. Like DmORC6, CfORC6 has leucine-rich region in the relevant site. Northern Blot showed that CfORC6 mRNA is about 2,000nt. Southern Blot confirmed that there is one copy of CfORC6 gene in spruce budworm genome. Western blot showed that infection of Cf124T cells with CfMNPV didn't affect the expression levels of CfORC6, at least up to 26 hr post infection.

The Study of the Implementation of the Boot System Using CF(Compact Flash) memory card 1. Implementation of the Boot System Using CF memory card (CF(Compact Flash)메모리 카드를 이용한 부트 시스템 구현에 관한 연구 1. CF메모리 카드를 이용한 부트 시스템 구현)

  • 이광철;김영길
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.8 no.1
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    • pp.108-114
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    • 2004
  • In this paper we propose the boot system using CF memory card and study the system implementation method. The system that is proposed in this paper basically consist of high performance microprocessor, small amount of program memory and CF memory card. And added LCD module and touch panel for the user interface. This system use the CF memory card and DRAM instead of the Flash memory, so it can reduce the system cost. And system performance is increased because of the system program running in the DRAM.

Preparation and characteristics of PP/CF/MWCNT nanocomposites (PP/CF/ MWCNT 나노복합체의 제조 및 특성평가)

  • Kim, Seung-Beom;Nam, Byeong-Uk;Lee, Kyu-Mann
    • Journal of the Semiconductor & Display Technology
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    • v.10 no.1
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    • pp.107-111
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    • 2011
  • Polypropylene(PP)/carbon fiber(CF)/multi-walled carbon nanotube(MWCNT) nanocomposites along with various CF and MWCNT contents were prepared in a Twin screw extruder. Electrical, mechanical property and morphology were investigated with a variation of CF and MWCNT contents. From the surface resistance of PP/CF/MWCNT composites, MWCNT can increase the conductivity of composites compared with PP/CF composites without MWCNT. It is suggested that MWCNT and CF can make the conductive network in the polymer matrix. Flexural modulus and Izod impact strength of the PP/CF/MWCNT composites were improved with the increase of CF contents. Morphology showed that length of CF in polymer matrix was shortened by torque during melt mixing with MWCNT. As a result of this phenomenon, the impact strength of composites was somewhat decreased.