• 제목/요약/키워드: Dispersion Variation

검색결과 276건 처리시간 0.023초

Sol-Gel and photoreduction 공정에 의한 Au 미립자분산 $TiO_{2}$ 박막 제조 (Preparation of Au fine particle dispersedf $TiO_{2}$ film by sol-gel and photoreduction process)

  • 현부성;김병일;강원호
    • 한국결정성장학회지
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    • 제9권1호
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    • pp.23-28
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    • 1999
  • Au 미립자가 분산된 $TiO_{2}$ 박막을 졸겔담금법과 열처리공정으로 실리카 유리기판위에 제조하였다. $TiO_{2}$ 박막제조는 titanium tetraisopropoxide-EtOH-HCl-$H_{2}O$-hydrogen tetrachloroaurat (III) tetrahydrate계를 이용하였다. 고농도로 Au 화합물을 함유하면서 투명한 코팅용액을 형성하는 조건을 검토하였다. Au 금속미립자의 크기를 조절하기 위하여 광환원공정을 채택하였다. UV 조사에 따른 Au 입자의 변화와 $TiO_{2}$ 매트릭스의 상전이과정을 XRD, SEM, TEM and UV-visible spectrophotometer로 관찰하였다. 분산제로서 CPCl (Cetylpyridinium chloride monohydrate)의 효과를 평가하였다.

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Effects of Hair Colors on the Image - Centered on Female Collegians in Their 20s -

  • Li, Eun-Ji;Shim, Boo-Ja
    • 패션비즈니스
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    • 제8권3호
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    • pp.49-58
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    • 2004
  • In the modern society, already a popular and public part of fashion, hair coloring has the effect of optical illusion on image. This study therefor aims to reveal the effects of varied and fashionable hair coloring on the body images. This is a combination of an actual examination and an experimental study. In order to know the effects of hair colors on body image, 230 female collegians residing in Busan were given a questionnaire on the reality of hair dyeing. Based on the actual research, one subject was selected and stimuli were manufactured. The analysis and examination of the effects of hair dyeing have produced the following conclusions. (1) As a result of dispersion analysis about the image effect according to hair colors, a meaningful difference is recognized in the item and indicates that hair color variation influences the image effect. (2) As a result, extracting the factors that hair colors can influence the image, 3 factors were extracted. The first factor is an intellectual image, the second factor is an active image, and the third factor is a comfortable image. (3) Image effect in hair colors are as same next. Red and Orange color clearly indicate the image of 'charismatic', 'lively', 'positive', 'active', 'light' and 'gorgeous'. Blue and Green color indicates the image of 'unfriendly', 'hard', 'cold' and 'uneasy'. White color indicates the image of 'unfriendly', 'charismatic', 'gorgeous' and 'impure' then Black color has images of 'friendly', 'intellectual', 'indignified' and 'pure'. In other words, the result indicates rather a different tendency comparison with the general color image.

고온 세라믹필터의 펄스젯 탈진 성능에 관한 연구 (A Study on the Performance of Pulse Jet Cleaning in High Temperature Filter)

  • 김병렬;박승철;박병철;조현준;오형모;황태원;신상운
    • 방사성폐기물학회지
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    • 제3권1호
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    • pp.9-16
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    • 2005
  • To evaluate parameters influencing on the dust removal of the High Temperature Filter(HTF) system, a computer simulation of fluid dynamics inside the system had been performed. The results showed that the optimum pulse jet periods were 50ms and 90ms for the 1000mm and 1500mm long filter elements respectively. Dust removal effect was very excellent under the pulse jet pressure of 3 bar. But the distance between the pulse jet nozzle and the venturi of a filter element had no meaningful effect on the performance with the variation from 5mm to 10mm. Compared to the dispersion mode of pulse jet, the collective mode of pulse jet flow was preferable in maintaining the pressure inside the system stable.

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고밀도 폴리에틸렌의 전계 세기의 영향 (Pigment Influence of High Density Polyethylene Electrical Strength)

  • 최용성;위성동;황종선;이경섭
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2008년도 춘계학술대회 논문집 센서 박막재료연구회 및 광주 전남지부
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    • pp.50-53
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    • 2008
  • In this work, the $TiO_2$ pigment influence in HDPE dielectric strength was analyzed. Chemical and structural characterizations were made to identify changes during the processing and your influence in the electrical properties. Formulations containing 0, 0.5, 1, 2.5, 4 and 6 of titanium dioxide were processed by extrusion and injection molding with stabilization-antioxidants, ultraviolet stabilizers and plasticizers. The electrical strength tests were analyzed by the statistical distribution of Weibull, and the maximum likelihood method. The high concentrations present lower values to electrical strength. The $\beta$ parameter could be using to insulator particles dispersion. The $TiO_2$ concentration variation shows that these incorporations implicate strength values increase has a maximum (5,35MV/cm). High pigment concentration induces a little falls in property values. Observing the $\beta$ parameter, minimum experiment electric field (Ebmin) and electric strength value, found that the best electric perform formulation was the formulation with 2.5% $TiO_2$ weight.

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44i BOO의 자외선 방출연구 (UV LINE EMISSIONS OF 44i BOOTIS)

  • 한동주;김용기;한원용;이우백
    • Journal of Astronomy and Space Sciences
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    • 제15권2호
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    • pp.335-340
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    • 1998
  • IUE 저 분산 관측자료를 가지고 W-UMa 형 별인 44i Boo의 자외선 광도곡선을 완성하였다. 채층과 전이영역으로부터 나오는 방출선의 변화를 알아보기 위해서 CI, CII, CIV, SiIV, Hell 선의 방출선 세기를 계산하였다. CIV 방출 선이 가장 강한 방출을 보였으며, CII, Hell, CI, SiV의 순서로 방출선의 세기가 관측되었음이 확인되었다. 또한 방출선의 세기가 주기적으로 변하고 있음을 확인하였고, 모든 방출 선들이 위상 0.2와 0.8부근에서 상대적으로 강한 방출 선을 보인다. 이는 44i Boo의 표면에서 채층 및 전이영역의 활동성으로 인해 자외선 방출이 불 균일하게 나오고 있음을 나타내는 것이라고 해석할 수 있다. 채층 활동의 변화로 인해 관측시간이 서로 다를 때 자외선 방출선의 변광 형태도 달라지고 있음을 확인하였다.

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파랑과 속도전단에 의한 유출유의 분산 특성 (Dispersion Characteristics of Spilled Oil by Waves and Velocity Shear)

  • 설동관;류청로;김종규
    • 한국해양환경ㆍ에너지학회지
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    • 제1권2호
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    • pp.18-26
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    • 1998
  • 본 논문은 쇄파와 속도 전단에 의해 발생하는 난류에 의해 해상에 유출된 기름이 유적으로 분해되어 해수면 하로 분산되어 가는 과정을 논하였다. 유막 분산의 역학적 메커니즘을 파악하기 위하여 두 가지 수리실험, 즉 전단발생장치와 조파수조를 이용하여 난류를 발생시켰다. 이러한 실험으로부터 혼합시간이 증가함에 따라 수면에 형성된 유막은 수십 마이크로미터에서 수백 마이크로미터의 입경을 가진 유적으로 분산되었다 뿐만 아니라 유출된 기름의 풍화정도에 따라서 상이한 분산 메커니즘을 나타내는 것을 확인할 수 있었다.

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실리카 입자를 이용한 눈부심 방지용 박막의 제조 및 특성 (The Synthesis and Characterization of Thin Film for Anti-Glare Using Silica Particles)

  • 안재범;노시태
    • 공업화학
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    • 제19권6호
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    • pp.685-689
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    • 2008
  • 충전제의 종류 및 분산 시간에 따른 박막의 특성 평가를 실시하였으며, 그 결과 투과도 측면에서 유리한 중공 실리카를 선택하여 충전제의 함량별 그리고 코팅 두께별 haze, 투과도, 그리고 광택도에 대한 실험을 각각 실시하였다 그 결과, 충전제의 함량이 증가할수록 haze값은 증가하고 광택도 값은 이와는 반대로 감소하였다. 또한, 필름 표면에의 코팅 두께가 증가할수록 충전제의 함량변화 때와는 정 반대로 haze값은 감소하고 광택도는 증가하였다. 그리고 투과도의 경우에는 두 가지 경우 모두 거의 일정한 수준으로 변화를 보이지 않았다. 결론적으로 충전제로서 중공 실리카를 사용할 경우 함량 증가와 투과도면에서 매우 유리함을 알 수 있었다.

망목특성에서의 자료분석을 통한 SN비의 선택 (Selection of Signal-to-Noise Ratios through Simple Data Analysis)

  • 임용빈
    • 품질경영학회지
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    • 제22권4호
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    • pp.1-12
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    • 1994
  • 각각의 설계인자들의 실험조건에서 얻어지는 특성치들의 분산은 평균에 영향을 받는다. 많은 경우에 평균이 커짐에 따라서 분산이 커지는 경향이 있다. 다구찌가 산포제어인자를 찾기 위해서 제시한 SN 비인 $(SN)_i$ = 10 log ($\bar{y}_{i}^{2}/s_{i}^{2}$) 은 분산이 평균의 제곱에 비례하여 커지는 경우이다. 그런데 분산이 평균의 제곱보다 더 느리게 또는 더 빠르게 커질 수도 있기 때문에 이 논문에서는 간단한 자료분석적 기법에 의해서 그 관계를 추측하여, 합당한 SN 비를 사용할 것을 제시하였고, 평균조정인자를 찾기위한 통계량인 감도 $(S)_i$ 의 통계적 성질들을 논의하였다.

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Bandgap capability of hybrid Kirigami inspired cellular structures

  • Del Broccolo, S.;Ouisse, M.;Foltete, E.;Scarpa, F.
    • Advances in aircraft and spacecraft science
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    • 제6권6호
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    • pp.479-495
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    • 2019
  • Periodic cellular core structures included in sandwich panels possess good stiffness while saving weight and only lately their potential to act as passive vibration filters is increasingly being studied. Classical homogeneous honeycombs show poor vibracoustic performance and only by varying certain geometrical features, a shift and/or variation in bandgap frequency range occurs. This work aims to investigate the vibration filtering properties of the AUXHEX "hybrid" core, which is a cellular structure containing cells of different shapes. Numerical simulations are carried out using two different approaches. The first technique used is the harmonic analysis with commercially available software, and the second one, which has been proved to be computationally more efficient, consists in the Wave Finite Element Method (WFEM), which still makes use of finite elements (FEM) packages, but instead of working with large models, it exploits the periodicity of the structure by analysing only the unit cell, thanks to the Floquet-Bloch theorem. Both techniques allow to produce graphs such as frequency response plots (FRF's) and dispersion curves, which are powerful tools used to identify the spectral bandgap signature of the considered structure. The hybrid cellular core pattern AUXHEX is analysed and results are discussed, focusing the investigation on the possible spectral bandgap signature heritage that a hybrid core experiences from their "parents" homogeneous cell cores.

SOCIAL RELATIONSHIP AND SPATIAL DISTRIBUTION IN A SMALL HERD OF JAPANESE BLACK CATTLE IN A DRY-LOT

  • Nakanishi, Y.;Mutoh, Y.;Umetsu, R.
    • Asian-Australasian Journal of Animal Sciences
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    • 제5권1호
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    • pp.183-188
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    • 1992
  • Behaviour of 7 horned Japanese Black Cattle (3-9 years old) kept in a $450m^2$ dry-lot under loose housing condition was observed in the daytime (0930-1730 h) during 3 consecutive days. Eating and lying behaviour of cattle and the positions of all animals when lying together were recorded at 10-min intervals. Agonistic encounters and social licking interactions in the herd were also recorded. The cattle established a social hierarchy which was near linear. An irregularity in the diurnal rhythm of lying behaviour was found on the 3rd day, which appeared to be caused by oestrus behaviour of a herdmate. Eating frequency showed greater variation among individuals than lying frequency, and the most dominant animal ate most frequently in the herd. The spatial pattern of the herd when lying indicated a relatively loose dispersion in the lot. Higher ranking cattle tended to lie down more frequently near the hay rack in the lot, so that lower ranking animals had more difficult access to feed. Cattle with more social licking interactions had a tendency to lie down near each other irrespective of proximity of social order, therefore it was suggested that social preference among particular individuals occurred in the herd.