• 제목/요약/키워드: photo-journal

검색결과 3,002건 처리시간 0.036초

Theoretical Studies on the Photo-Skinsensitizing Psoralens (I)

  • Ja-Hong Kim;Sang-Chul Shim
    • Bulletin of the Korean Chemical Society
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    • 제1권2호
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    • pp.71-73
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    • 1980
  • The electronic structure of photo-skinsensitizing psoralens has been investigated by the FMO method. On the basis of theoretical calculations, optimum value of indices (Ft=0.33) has been proposed which corresponds to the sum of frontier electron density. The results indicate that this index is closely correlated with photo-skinsensitizing carcinogenic activity. The formations of molecular complexes between DNA and photo-skinsensitizing carcinogens is discussed in terms of charge transfer interactions.

$UV/H_2O_2,\;UV/TiO_2/H_2O_2$, Photo-Fenton 산화방법에 의한 Citric Acid의 분해효율 비교 (Comparative Studies Of the $UV/H_2O_2,\;UV/TiO_2/H_2O_2$ and Photo-Fenton Oxidation for Degradation of Citric Acid)

  • 서민혜;조순행;하동윤
    • 대한환경공학회지
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    • 제28권4호
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    • pp.429-437
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    • 2006
  • 화학세정폐수에 함유되어 있는 citric acid의 효율적인 처리방안을 수립하기 위해 $UV/H_2O_2,\;UV/TiO_2/H_2O_2$, Photo-Fenton 산화방법을 이용하여 각각 citric acid의 제거효율 및 그에 따른 전력소비량을 평가하였다. 그 결과 조사된 최적 처리조건에서 $UV/H_2O_2,\;UV/TiO_2/H_2O_2$, Photo-Fenton 산화방법을 이용한 citric acid 농도에 근거한 TOC 제거효율은 각각 95.5%, 92.3%, 91.5%로 조사되었으며, 그에 따른 전력소비량은 $11.26kWh/m^3,\;3.85kWh/m^3,\;0.799kWh/m^3$으로 조사되었다. 이 결과에 의하면 세가지 광화학적 산화방법 모두 유기물질이 90% 이상 제거되어 citric acid의 분해에 효과적인 것으로 판단되었다. 그러나 Photo-Fenton 산화방법이 다른 방법에 비해 처리에 소요되는 반응시간이 짧은 것으로 나타났다. 또한 광화학적 산화방법의 운영비를 결정짓는데 중요한 요소인 전력소모량 측면에서도 Photo-Fenton 산화방법이 다른 방법에 비해 우수한 것으로 조사되어 본 연구에서 비교하는 세가지 방법 중 citric acid 처리에는 Photo-Fenton 방법이 효율적인면과 경제성면에서 가장 적합한 처리기술로 결론지을 수 있었다.

영상의 위치 정보를 위한 임베디드 지오코딩 시스템 구현 (Implementation of Embedded Geo-coding System for Image's Geo-Location)

  • 이용환;김영섭
    • 반도체디스플레이기술학회지
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    • 제7권3호
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    • pp.59-63
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    • 2008
  • Geo-coding refers to the process of associating data with location information, and the system deals with geographic identifiers expressed as latitude and longitude or street addresses. Although many services have been launched, there still remains a problem for users to create geo-coded photo with manually labeling GPS(Global Positioning System) coordinate or synchronizing with separate devices. In this paper, we design and implement a geo-coding system which utilizes the time and location information embedded in digital photographs in order to automatically categorize a personal photo collection. An included GPS receiver labels a photograph with its corresponding GPS coordinates, and the position of the camera is automatically recorded into the photo image header at the moment of capture. The place and time where the photo was taken allows us to provide context metadata on the management and retrieval of information.

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최종사용자요구중심의 PC Internet Stock Photo 시스템 구현 (The PC Internet Stock Photo Systems Implementation of End User Computing)

  • 권영직;백영욱;이승아
    • 한국산업정보학회논문지
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    • 제5권1호
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    • pp.69-76
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    • 2000
  • 본 논문에서는 최종사용자 중심 전산의 영향요인에 관한 이론연구를 바탕으로 최종사용자가 원하는 사진을 쉽게 검색할 수 있고, 사진작가는 자신의 작품을 직접 데이터베이스에 저장할 수 있는 Stock Photo 시스템을 인터넷상에서 운용되도륵 구현하였다. 또한 이러한 Stock Photo 시스템은 객체지향적인 방식으로 개발되어 소프트웨어의 수정과 재사용이 용이하며 거래와 지불에 관한 부분을 추가하여 전자거래의 한 형태로도 이용할 수 있도록 설계였다.

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First Hyperpolarizabilities of Heteroaromatic Stilbene Derivatives

  • Cho, Bong-Rae;Lee, Sang-Hae;Yosep Min;Kang, Tae-Im;Jeon, Seung-Joon
    • Journal of Photoscience
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    • 제8권2호
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    • pp.79-82
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    • 2001
  • 2-(p-Diethylaminostyryl)pyrrole (I) and 2-[5-diethylaminothienyl]vinyl]pyrrole (II) derivatives with systematic variation of the acceptors have been synthesized and their first hyperpolarizabilities were measured. The $\beta$ values increased systematically as the aromatic resonance energy decreased. Moreover, the value of $\beta$ for the former increased gradually as the acceptor strength increased. The opposite trend observed in the latter series of compounds has been attributed to the distorted structure caused by the steric hindrance between the N-methyl group and the acceptor moiety.

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새로운 광중합 가능한 폴리이미드계 몰리머을 이용한 액정 배향 특성 (Liquid Crystal Aligning Capabilities on a New Photo-Crosslinkable Polyimide Based Polymer)

  • 황정연;서대식;이상렬;김재형;한은주
    • 한국전기전자재료학회논문지
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    • 제14권5호
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    • pp.430-434
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    • 2001
  • We synthesized a new photo-crosslinkable polymer (polyimide (PI)-chalcone-biphenyl (BP)) and liquid crystal (LC) aligning capabilities for nematic (N) LC with obliquely polarized UV exposure on a photo-crosslinkable polymer were studied. The high pretilt angle in NLC was obtained by polarized UV exposure on a PI-Chal-BP surface for 3 min. The high pretilt angle generated in NLC is attributed to the biphenyl moieties and the photo-dimerized chalclone group of a photopolymer. Also, good thermal stability of a PI-Chal-BP were obtained by thermogravimetric analysis (TGA) measurement until 450$^{\circ}C$. Finally, good voltage-transmittance curves and response time were observed by UV exposure on a PI-Chal-BP surface for 3min.

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폴리이미드 소성 시에 UV 광조사를 이용한 프리틸트 발생에 대한 연구 (Investigation of pretilt generation by UV light irradiation during imidization of polyimide)

  • 서대식;김형규
    • 한국전기전자재료학회논문지
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    • 제13권1호
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    • pp.75-79
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    • 2000
  • In this study, we investigated the pretilt angle generation and liquid crystal (LC) alignment by ultravi-olet (UV) light irradiation during imidization of polymide. The generated pretilt angle of nematic (N) LC by using the in-situ photo-alignment method was smaller than that of the conventional UV photo-alignment method. Also, generated pretilt angle of NLC tends to increase by annealing. In case of using the polymer(AL-3046), we found that the in-situ Uv photo-alignment method has higher thermal stability of LC alignment, but it has a disadvantage to control pretilt angle.

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Cholesteryl 기를 함유한 수직배향용 광폴리머 재료의 합성 및 배향 효과 (Liquid crystal alignment effect and synthesis of photo-polymer material containing cholesteryl moiety for homeotropic alignment)

  • 황정연;서대식;한은주
    • 한국전기전자재료학회논문지
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    • 제13권9호
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    • pp.770-775
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    • 2000
  • A new photo-polymer material of the copoly (PM4Ch-ChMA), copoly (poly (4-methacryloyloxy)chalcone-cholesteryl methacrylate) for homeotropic alignment was synthesized and the electro-optical (EO) performance for the photo-aligned vertical-aligned (VA)-LC display (LCD) was studied. Good thermal stabilities of synthesized copolymer were obtained by TGA(Thermogravimetric Analysis) measurement. Good voltage-transmittance (V-T) and response time characteristics for the photo-aligned VA-LCD with polarized UV exposure in oblique direction($\theta$$_{i}$=30$^{\circ}$) on a copolymer-1 (2%) surfaces for 1 min were observed. but, light leakage in the off-state was observed. Therefore, we achieved excellent V-T and response time characteristics for the photo-aligned VA-LCD with UV exposure on a copolymer-3 (30%) surfaces for 3 min.n.

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광 가교성 폴리이미드의 광배향 특성 (The Characteristics of Photo-alignment with Photo-crosslinkable Polyimide)

  • 신동명;조선주;손병청;최정우;이미혜;최길영
    • 한국응용과학기술학회지
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    • 제16권1호
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    • pp.15-20
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    • 1999
  • Photo-crosslinkable polyimide(PI) which contains CF3 moiety was synthesized. Polarized UV light transformed ketone group of PI to hydroxyl group, which was confirmed by IR and UV-visible spectroscopy. We investigated the dichroic UV-absorption before and after photo-reaction with linearly polarized light. In particular we have attempted to clarify the relationship between the anisotropy of surface region and surface azimuthal anchoring energy and knew that the anchoring energy of photo-alignment PI is comparable with that of mechanical rubbing.

에이즈 감염인 사진전의 효과 (The Effects of an AIDS Photo Exhibition on AIDS Knowledge and Attitudes)

  • 강희선;신수린;장순복;강경화
    • 한국보건간호학회지
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    • 제19권2호
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    • pp.241-248
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    • 2005
  • This study examined the effects of a photographic exhibition of HIV/AIDS on people's AIDS knowledge and attitudes. The subjects in this study were 620 people who came to see the AIDS photo exhibition that was held in Seoul, Ansan and Ulsan area. The data were collected before and after seeing the AIDS photo exhibition by using structured questionnaires from July 21, 2003 to July 31, 2004. The result indicated that there were differences in AIDS knowledge and attitudes after viewing the photo exhibition and the differences were statistically significant. The results suggested that the AIDS photo exhibition was effective for increasing knowledge about AIDS and changing the attitude toward people with AIDS. Therefore, it is recommended to utilize the AIDS photos exhibition for AIDS prevention education.

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