• 제목/요약/키워드: Wide field

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Fringe-Field 구동형 새로운 반투과형 수평 배향 액정 디스플레이 (A Novel Transflective Homogeneously Aligned Liquid Crystal Display Driven by Fringe-Field)

  • 정태봉;이승희
    • 한국전기전자재료학회논문지
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    • 제16권6호
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    • pp.501-509
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    • 2003
  • We have designed transflective liquid crystal display(LCD) associated with in-plane switching of a LC director driven by fringe-field, unlike other LCD mode. Reflective area consists of a λ/2 compensation film and a LC cell with retardation value(dΔn) of λ/4 with their optic axes making an angle of 15$^{\circ}$ and 75$^{\circ}$ against polarizer, respectively. In the transmissive area, top and bottom polarizers are parallel each other, an LC has a dΔn of λ/2, and another λ/2 compensation film is inserted between the LC cell and bottom polarizer. With the configuration, both devices show dark state initially. When an incident light is 550nm, the device shows wide-viewing-angle characteristics such that in the reflective area the contrast ratio target than 5 exists up to 55$^{\circ}$ of polar angle in all directions and in transmissive area it exists about 100$^{\circ}$ in vortical direction and 110$^{\circ}$ in horizontal direction.

Wide-Field Near-IR Photometric Study for Spatial Distribution of Stars around Globular Clusters in the Galactic Bulge

  • Chang, Cho-Rhong;Chun, Sang-Hyun;Han, Mi-Hwa;Jung, Mi-Young;Lim, Dong-Wook;Sohn, Young-Jong
    • 한국우주과학회:학술대회논문집(한국우주과학회보)
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    • 한국우주과학회 2009년도 한국우주과학회보 제18권2호
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    • pp.29.4-30
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    • 2009
  • Extra-tidal feature of the globular clusters such as tidal tails and halos can be a crucial evidence of the merging scenario of the Galaxy formation in the dynamical point of view. To search for such an extra-tidal feature of globular clusters located in the Galactic bulge(RGC<3kpc), we obtained wide-field near-infrared JHKs images of 6 metal-poor ([Fe/H]<-1.0) clusters and 3 metal-rich ([Fe/H]>-1.0) clusters. Observations were carried out using IRSF 1.4m telescope and SIRIUS near-infrared camera, during 2006~2007. The obtained images have a total maximum field-of-view of ~ $21'\times 21'$. To select clusters' member stars and minimize the field star contaminations, we applied CMD masking algorithm. Smoothed surface density contour maps with selected stars for each cluster show overdensity features around the tidal radius and beyond. Also, radial surface density profiles within the tidal radius of the clusters show an overdensity feature as a change of slope of the radial profile. The results add further observational constraints of the formation of the Galactic bulge.

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Single Plane Illumination Microscopy - MicroPIV를 이용한 버블 유동에서 외부 자계 영향을 받는 자성입자 가시화 (Flow Visualization of Magnetic Particles under the external magnetic field in bubbly flow using Single Plane Illumination Microscopy - MicroPIV)

  • 이창제;조경래;이상엽
    • 한국가시화정보학회지
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    • 제19권1호
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    • pp.36-42
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    • 2021
  • This study measured the velocity of magnetic particles inside the power generation using external heat sources. Single Plane Illumination Microscopy (SPIM) was used to measure magnetic particles that are simultaneously affected by bubbly flow and magnetic field. It has the advantage of reducing errors due to particle superposition by illuminating the thin light sheet. The hydraulic diameter of the power generation is 3mm. Its surface is covered with a coil with a diameter of 0.3 mm. The average diameter of a magnetic particle is 200nm. The excitation and emission wavelengths are 530 and 650nm, respectively. In order to find out the flow characteristics, a total of four velocity fields were calculated in wide and narrow gap air bubbles, between the wall and the air bubble and just below the air bubble. Magnetic particles showed up to 8.59% velocity reduction in the wide gap between air bubbles due to external magnetic field.

사생활 침해 방지를 위한 Person Wide Web 기반 1인 미디어 (1 Person Media Based on Person Wide Web for Preventing Privacy Risk)

  • 윤지섭;마정미;소선섭;은성배
    • 정보처리학회논문지:컴퓨터 및 통신 시스템
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    • 제5권10호
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    • pp.339-346
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    • 2016
  • 1인 미디어가 개인의 욕구분출과 인터넷의 발달이 맞물리면서 정보화 시대의 대세로 자리매김하였다. 하지만, 인터넷의 접근성은 의도치 않던 사생활 침해 우려를 낳고 있으며 폐쇄적인 SNS의 수요를 중가시키는 실정이다. 본 논문에서는 PWW(Person Wide Web)를 이용하여 1인 미디어를 생성하고 타인과 공유하는 1인 미디어 체계를 제시한다. PWW는 스마트폰과 모바일 앵커, 개인의 클라우드 스토리지로 구성된 웹 기반의 정보체계이다. 현장의 객체에 부착된 모바일 앵커로부터 개인 클라우드 저장소의 주소를 얻고 그 주소에 저장된 웹문서를 가져와 스마트폰의 웹뷰에서 처리한다. 또한, PWW 방식의 1인 미디어 체계를 설명하고 현장에서 1인 미디어를 활용한 예를 제시한다. WWW 방식의 1인 미디오와 PWW 방식의 1인 미디어의 보안성을 비교, 분석하였으며, PWW 방식의 1인미디어가 더 높은 보안성을 갖는 것을 보였다.

Considering Cell-based Assays and Factors for Genome-wide High-content Functional Screening

  • Chung, Chul-Woong;Kim, In-Ki;Jung, Yong-Keun
    • Animal cells and systems
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    • 제13권2호
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    • pp.97-103
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    • 2009
  • Recently, great advance is achieved in the field of genome-wide functional screening using cell-based assay. Here, we briefly introduce well-established and typical cell-based assays of GPCR and some parameters which should be considered for genome-wide functional screening. Because of characters and importance of GPCR as drug targets, several ways of assay systems were devised. Among them, high-content screening (HCS) that is based on the analysis of image by confocal microscope is becoming favorite choice. The advances in this technology have been driven exclusively by industry for their convenience. Now, it is turn for academy to define more detail signaling networks via HCS using cDNA or siRNA libraries at genome-wide level. By isolating novel signaling mediators using cDNA or siRNA library, and postulating them as new candidates for therapeutic target, more understanding about life science and more increased chances to develop therapeutics against human disease will be achieved.

시각 기반 감시 및 관측을 위한 광각 영상에서의 중첩된 보행자 구분 (Dividing Occluded Pedestrians in Wide Angle Images for the Vision-Based Surveillance and Monitoring)

  • 박재형;도용태
    • 센서학회지
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    • 제24권1호
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    • pp.54-61
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    • 2015
  • In recent years, there has been increasing use of automatic surveillance and monitoring systems based on vision sensors. Humans are often the most important target in the systems, but processing human images is difficult due to the small sizes and flexible motions. Particularly, occlusion among pedestrians in camera images brings practical problems. In this paper, we propose a novel method to separate image regions of occluded pedestrians. A camera equipped with a wide angle lens is attached to the ceiling of a building corridor for sensing pedestrians with a wide field of view. The output images of the camera are processed for the human detection, tracking, identification, distortion correction, and occlusion handling. We resolve the occlusion problem adaptively depending on the angles and positions of their heads. Experimental results showed that the proposed method is more efficient and accurate compared with existing methods.

나선형 포트를 적용한 광각엔진에서 실린더 내 압축 유동 특성 (In-Cylinder Compression Flow Characteristics of Helical Port Engines with Wide Valve Angle)

  • 엄인용;박찬준
    • 대한기계학회논문집B
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    • 제33권1호
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    • pp.9-16
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    • 2009
  • This paper is the second of 2 companion papers which investigate in-cylinder swirl generation characteristics in helical port engine with wide valve angle. Two wide valve-angle engines, which are same ones and have slightly different rig swirl number, were used to compare the characteristics of cylinder-flow. One intake port is deactivated to induce swirl flow. A PIV (Particle Image Velocimetry) was applied to measure in-cylinder velocity field during intake stroke. The results show that the intake flow component passing through valve area near the cylinder wall is not negligible in helical port engine with wide valve angle contrary to conventional one. The effect of this velocity component on in-cylinder increases as the swirl ratio rises and compression process progresses. Consequently, this component destroys in-cylinder swirl flow completely during compression resulting in no actual swirl at the end stage of compression.

나선형 포트를 적용한 광각엔진에서 실린더 내 흡입 유동 특성 (In-Cylinder Intake Flow Characteristics of Helical Port Engines with Wide Valve Angle)

  • 엄인용;박찬준
    • 대한기계학회논문집B
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    • 제32권10호
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    • pp.761-768
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    • 2008
  • This paper is the first of 2 companion papers which investigate in-cylinder swirl generation characteristics in helical port engine with wide valve angle. Two wide valve-angle engines, which are same ones and have slightly different rig swirl number, were used to compare the characteristics of cylinder-flow. One intake port is deactivated to induce swirl flow. A PIV (Particle Image Velocimetry) was applied to measure in-cylinder velocity field during intake stroke. The results show that the intake flow component passing through valve area near the cylinder wall is not negligible in helical port engine with wide valve angle contrary to conventional one. The effect of this velocity component on in-cylinder increases as the swirl ratio rises and intake process progresses. Consequently, this component interferes the formation of in-cylinder swirl flow resulting in lower actual swirl.

OPTICAL/NIR IMAGING OF AKARI NEP-WIDE SURVEY FIELD

  • Jeon, Yiseul;Im, Myungshin
    • 천문학논총
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    • 제27권4호
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    • pp.145-146
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    • 2012
  • We present the results from B-, R-, I-, J- and H-band observations of the NEP-Wide survey field. The NEP-Wide survey is an AKARI survey of the North Ecliptic Pole covering ~ 5 square degrees area. Our optical/NIR imaging supports the AKARI IR imaging data by providing a crucial coverage in the optical/NIR. The optical data were obtained in 2007 using the 1.5 m telescope and SNUCAM at Maidanak Observatory, Uzbekistan. The NIR data were obtained in 2008 with FLAMINGOS on the KPNO 2.1 m telescope. We used IRAF, SExtractor, SCAMP, and SWarp for reducing the raw data, I-band fringe pattern removal, astrometry, standard photometry calibration, and source detection. Our optical-NIR data reach the depths of B ~ 23.4, R ~ 23.1, I ~ 22.3, J ~ 21.05, and H ~ 20.64 AB mag at 5-sigma. Here, we present the astrometric accuracy, galaxy number counts, completeness, and reliability, as well as redshift tracks of some normal galaxies and quasars on the B - R vs. R - I color-color diagram. The photometric data are being used for identifying optical counterparts of the IR data provided by AKARI, studying their SEDs, and selecting interesting objects for spectroscopic follow-up studies.

Subaru Strategy for 2020's

  • Arimoto, Nobuo
    • 천문학회보
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    • 제40권2호
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    • pp.27.2-27.2
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    • 2015
  • Strategic plan of Subaru science and operation will be introduced. Currently, Subaru has wide variety of instruments, conducts only classical observations, with less than 5 nights allocation for each proposal. Near future, Subaru will emphasize on surveys, introduce queue mode observations, reduce the number of instruments, and concentrate on large size programs. Large surveys are called Subaru Strategic Programs (SSPs). HSC-SSP is on-going (300 nights for 5 years), PFS-SSP will start at around 2020 (360 nights for 5 years), and IRD-SSP from 2016 (TBD). HSC science includes 1) cosmology with gravitational lensing, 2) lensing studies of galaxies and clusters, 3) photometric redshifts, 4) the Solar system, 5) the Milky Way and the Local Group, 6) AGN/quasars, 7) transients, 8) galaxies at low/high redshifts, and 9) clusters of galaxies. PFS science includes 1) cosmology, 2) galaxy & AGN, and 3) galactic archaeology. Subaru is planning the third pillar instrument, so called ULTIMATE-Subaru, which is the GLAO optical-NIR wide field camera & multi-IFU spectrograph for finding galaxies at ultra high redshift (z>10). Finally the strategy from Subaru to TMT will be presented. Subaru will conduct four major SSPs (HSC, PFS, IRD, ULTIMATE-Subaru) in coming decade to provide targets to TMT. HSC performs wide field surveys to reveal the distribution of dark matter in the Universe. IRD surveys Earth-like young planets to discover ~20 Earth-like habitable planets. PFS studies the expanding Universe to provide a few million emission line galaxies to TMT.

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