• 제목/요약/키워드: photo

검색결과 4,242건 처리시간 0.027초

Improvement of Photo-Alignment Characteristics for Device Applications

  • Hwang, Yong-Jae;Choi, Kil-Yeong;Yi, Mi-Hie;Hong, Sung-Hwan;Shin, Dong-Myung
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권1호
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    • pp.867-870
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    • 2007
  • In order to solve image sticking phenomena, the gas-phase and liquid-phase interfacial reactions of photosensitive polyimide can annihilate photoreactive carbon-carbon double bonds, which remain after photo-alignment process. The annihilation processes dramatically affect residual DC and photochemical reorientation of photoactive functional groups.

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경사진 자외선 조사를 이용한 TN-LCD의 전기광학 특성 (Electro-optical performance of TN-LCD wish oblique UV light irradiation on polyimide surface)

  • 서대식;박두석;한정민;황율연;박태규
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1998년도 춘계학술대회 논문집
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    • pp.113-116
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    • 1998
  • In this paper, we studied the electro-optical(EO) performance of photo-aligned twisted nematic(TN)-liquid crystal display(LCD) with oblique non-polarized ultraviolet(UV) light irradiation on polyimide(Pl) surface. We observed that the voltage-transmittance and response time characteristics of photo-aligned TN-LCD is almost same compared to conventional TN-LCD. Also, we observed that the voltage-holding-ratio(VHR) of photo-aligned TN-LCD is almost same compared to conventional TN-LCD.

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PPG 측정에 의한 개인 인증 방법 (Individual verification method by PPG measurement)

  • 김신자;이영우
    • 한국정보통신학회논문지
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    • 제12권11호
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    • pp.2057-2061
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    • 2008
  • 사람의 심박동은 심장 상태와 구조, 나이 등의 여러 요소에 의하여 고유한 특성을 갖는다. 본 논문에서는 심박동의 고유 특성을 이용한 개인 인증 방법을 제안하였다. 이 고유 특성은 LD와 PD를 이용, 광전용적 맥파(PPG, Photo Plethysmogram)를 측정함으로서 얻었다.

The “Trivial” Mechanism for the Photo-Fries Reaction of Phenyl Acetate and Biphenylyl Acetates

  • 윤효정;고성혜;고미경;최우기
    • Bulletin of the Korean Chemical Society
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    • 제21권9호
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    • pp.901-904
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    • 2000
  • The mechanism for the photo-Fries rearrangement of phenyl acetate andbiphenylyl acetates were reinvestigat-ed in phenol (or phenol derivatives) containing media. The results showed that the phenol (or phenol deriva-tives) which is the most common by-product of Fries reaction reacts with acyl radical togive Fries-product. These phenol (or phenol derivatives) contributions to the Fries-products were suggested as the Trivial mecha-nism for the photo-Fries reaction.

Artificial Radical Generating and Scavenging Systems: Synthesis and Utilization of Photo-Fenton Regent in Biological Systems

  • Matsugo, Seiichi
    • Journal of Photoscience
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    • 제9권2호
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    • pp.138-141
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    • 2002
  • A photo-labile compound which is bioinactive but, upon irradiation with light, yields bioactive species is called as "caged compound". Photolysis of caged compounds generating bioactive species, has become a general method to produce a desired amounts of bioactive species in the specific time interval at the desired place or area of the target biological systems. For this purpose, we designed and synthesized caged hydroxyl radical., "Photo-Fenton Reagent" NP-IIl. NP-IIl has a strong absorption maximum at 377 nm and yields hydroxyl radicals upon UV light irradiation. The antioxidant activity of the ${\alpha}$ -lipoic acid and other naturally occurring compounds has been examined by using NP-IIl as a molecular probe. For example, upon photoirradiation of NP-lII with BSA or apolipoprotein of human low density (LDL), the significant oxidative modifications were observed in both cases. The oxidation was completely suppressed in the presence of ${\alpha}$-lipoic acid, which clearly demonstrates the strong hydroxyl radical scavenging activity of ${\alpha}$-lipoic acid. Other applications of NP-lII will also be described

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REPRESSION OF Lhcb GENES FOR CHLOROPHYLL a/b-BINDING PROTEINS UNDER HIGH-LIGHT CONDITIONS IN Chlamydomonas

  • Haruhiko Teramoto;Akira Nakamori;Jun Minagawa;Ono, Taka-aki
    • Journal of Photoscience
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    • 제9권2호
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    • pp.373-375
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    • 2002
  • Lhcb genes encoding light-harvesting chlorophyll-a/b binding (LHC) proteins of photosystem (PS) II were comprehensively characterized using the expressed sequence tag (EST) databases in the green alga, Chlamydomonas reinhardtii. The gene family was composed of eight Lhcb genes including four new genes, which were isolated and sequenced. The effects of light intensity on the levels of mRNAs accumulation of multiple Lhcb genes were studied under various conditions. The results indicate that Lhcb genes are coordinately regulated in response to light conditions, and repressed when the input light energy exceeded the requirement for $CO_2$ assimilation. The effects of high light on the expression of the Lhcb genes observed in the presence of an electron transport inhibitor, DCMU, and in mutants deficient in photosynthetic reaction centers suggest the presence of two alternative mechanisms for regulating the genes expression under high-light conditions.

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도로시설물 관리를 위한 Photo Database 설계에 관한 연구 (A Study on the design of Database for photograph of Road Facilities)

  • 엄우학;정동훈;김정현;김병국
    • Spatial Information Research
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    • 제11권1호
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    • pp.33-40
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    • 2003
  • 본 논문에서는 도로 및 도로시설물의 신설과 보완에 관련된 정보의 효과적인 관리를 위해 CCD(Charge-Coupled Device) 카메라, GPS(Global Positioning Systems), INS(Inertial Navigation Systems)와 같은 3개의 위치관측센서를 통합한 차량을 이용하여 시범지역을 측량하고 이를 통해 획득된 자료를 구조적으로 Photo Database에 저장할 수 있는 방안을 제시하였다. 저장된 Database를 이용한 도로시설물관리시스템의 프로토타입(Prototype)은 해당지점에 대한 실제사진을 이용해서 사용자의 대상물에 대한 인식성을 높이고 속성정보와의 연계를 통해서 해당 시설물에 대한 정성적인 정보추출과 관리가 가능함을 보여주었다.

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측쇄기를 가진 폴리머의 폴리이미드 소성 방법에 따른 액정 배향 효과 (Liquid crystal alignment effects by imidization methods of the polyimide on the polymer with side chain.)

  • 서대식;김형규
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2000년도 춘계학술대회 논문집 디스플레이 광소자 분야
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    • pp.177-180
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    • 2000
  • In this study, we investigated the pretilt angle generation and liquid crystal (LC) alignment by ultraviolet (UV) exposure during imidization of polyimide on the polymer with side chain. The generated pretilt angle of nematic (N) LC using in-situ photo-alignment method was smaller than that of the conventional UV photo-alignment method. Also, the generated pretilt angle of NLC tends to increase by annealing.

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비정질 칼코게나이드박막으로서의 Ag 도핑효과에 대한 U-형 모델 (The U-type Model on Ag Doping effect in Amorphous Chalcogenide thin films)

  • 김민수;이현용;정홍배
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1995년도 춘계학술대회 논문집
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    • pp.50-53
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    • 1995
  • In this paper we have obtained property by considering the change of optical energy gap as a function of photo-does for exposing photo on Ag/a-Se$\sub$75/Ge$\sub$25/ thin films. This U-type property was obsered for all photo-exposing except for blu-pass filtered Hg lamep. Expecially, very large band shift(~0.3[eV]) is obtained by exposing He-Ne laser (6328[${\AA}$]). It is impossible to explain this property for exposing He-Ne and semiconductor laser through DWP model, which was explained for photo-exposing above the energy gap. Therefore we suggest a new modified model of DWP model for Ag/a-Se$\sub$75/Ge$\sub$25/ bilayer thin films.

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복셀 컬러링을 위한 시점 계획 (View Planning for the voxel coloring)

  • 성영훈;윤일동;이상욱
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2001년도 제14회 신호처리 합동 학술대회 논문집
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    • pp.705-708
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    • 2001
  • 여러 장의 입력 영상으로부터 3차원 형상 정보를 복원하는 기법은 크게 스테레오(stereo) 기법과 각선 기반 방법으로 나누어져 있다. 특히 복셀 기반 방법은 스테레오 기법에서의 대응점 문제를 극복하고 가리어짐 현상이나 컬러의 변화가 적은 영역에서의 현상 복원 능력이 우수한 것으로 알려져 있지만 광학적 외피(photo hull) 이라는 근본적인 복원 한계성을 가진다. Photo hull은 바라보는 카메라의 위치에 크게 의존하는 성질을 보인다. 조건에 맞는 최적의 카메라 위치를 결정하는 것을 시점 계획(view planning)이라 고 하고 거리 영상(range images)로부터 형상을 복원하는 기법에 활발히 연구되어져 왔다. 본 논문에서는 복셀 기반 방법에서의 단점인 photo hull을 줄이기 위해 최적의 시점을 선택하는 시점 계획(view planning)에 대한 알고리듬을 제안하고 photo hull의 효과를 최소로 하여 형상이 복원되는 것을 실험을 통해 검증한다.

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