• Title/Summary/Keyword: Illumination system

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The Effect of Cure History on the Fluorescence Behavior of an Unsaturated Polyester Resin with A Fluorescence Probe

  • Donghwan Cho;Yun, Suk-Hyang;Bang, Dae-Suk;Park, Il-Hyun
    • Macromolecular Research
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    • v.12 no.3
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    • pp.282-289
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    • 2004
  • We have extensively characterized the fluorescence behavior of unsaturated polyester (UP) resin in the absence and presence of a 1,3-bis-(l-pyrenyl)propane (BPP) fluorescent probe at various dynamic and isothermal cure histories by means of a steady-state fluorescence technique using a front-face illumination equipment. In addition, we explored the effect of the fluorescence intensity on the relaxation of the fluorescent probe in the UP resin by resting the dynamically and isothermally cured resin at ambient temperature and pressure for 24 h. The monomer fluorescence intensity, which has two characteristic peaks at 376 and 396nm, changed noticeably depending on the cure temperature and time and provided important information with respect to the molecular and photophysical responses upon curing. The result of the fluorescence study indicates that the increased local viscosity and restricted molecular mobility of the UP resin surrounding the BPP probe after curing are both responsible for the enhancement of the monomer fluorescence intensity. Our results also demonstrate that once the BPP probe has enough time to rearrange and become isolated prior to fluorescence, a sufficient amount of fluorescence is emitted. Therefore, we note that the fluorescence behavior of this UP resin system is influenced strongly by the relaxation process of the fluorescent probe in the resin as well as process used to cure the resin.

A Study on the Optimal Window Floor Ratio Acording to Transmitance of Dye Sensitized Solar Cell(DSSC) by Analysis of Daylighting perfomance and Glare Index of Transmitance (염료감응태양전지의 투과율에 따른 채광성능 및 현휘지수 분석을 통한 적정창면적비에 대한 연구)

  • Oh, Myung-Hwan;Sim, Se-Ra;Lee, Chul-Sung;Chin, Kyung-Il;Yoon, Jong-Ho
    • 한국태양에너지학회:학술대회논문집
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    • 2009.11a
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    • pp.92-97
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    • 2009
  • It is more necessary to consider the various factors for developmenting visible PV module of alternative window than traditional PV module. It must have sufficient performance which is Tvis, daylighting, daylight factor, glare index. so that more needs to consider suitable plan and total evaluated technology. Under the this background. For using commonly a combination BIPV module system and Daylinghting that can alternative architectural window, our goal on this study is drawing proper window area ratio as the window by analyzing lighting performance and glare index depending on transmittance of DSSC. On this study, we drew the result about window area ratio that can apply in the building when applying DSSC in the window. In situation that window is alternated as curtain wall in atrium that has big Widow area, if applying red 15.8% DSSC of low transmittance, it is expect to proper because it is suitable illumination standard and doesn't occur a discomfort glare. In case of office, we propose to apply red 33.2% or blue 35.2% DSSC of high transmittance for no affecting lighting load. we expect to contribute to select proper and effective window when applying the window in the building by drawing the window area ratio that can apply in thee building depending on transmittance of DSSC and offering the glare index data.

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The Study about the Differential compression based on the ROI(Region Of Interest) (ROI(Region Of Interest)기반의 차등적 이미지 압축에 관한 연구)

  • Yun, Chi-Hwan;Ko, Sun-Woo;Lee, Geun-Ho
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.18 no.3
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    • pp.679-686
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    • 2014
  • Recently, users can get countless images and videos by network. So, the compression technology of image and video is researched more and more. However, the situation which is the interested range of the image is occurred. For instance, since the region of face is more important than background, the image compression technology bases on the region of interest (ROI) is necessary, in the ATM environment. In this research, given the human visual system, which are not sensitive to illumination variations at very dark and light regions of image, we calculate the standard deviation of block and use this value to define the ROI. In encoding process, the relatively high quality can be obtained at the ROI and the relatively low quality can be obtained at the non ROI. In proposed scheme, the feature which is the encoding process according to subjectively image quality can be demonstrated. Finally, this proposed scheme is applied to JPEG standard. The experimental results demonstrate that proposed scheme can achieve better image quality at the high compression ratio.

Growth and Optoelectric Characterization of CdGa$_2$Se$_4$ Sing1e Crystal Thin Films (Hot Wall Epitaxy (HWE)에 의한 CdGa$_2$Se$_4$ 단결정 박막 성장과 광전기적 특성)

  • 홍광준;박창선
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2001.11a
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    • pp.167-170
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    • 2001
  • The stochiometric mix of evaporating materials for the CdGa$_2$Se$_4$ single crystal thin films was prepared from horizontal furnace. To obtain the single crystal thin films, CdGa$_2$Se$_4$ mixed crystal was deposited on thoroughly etched semi-insulating GaAs(100) substrate by the Hot Wall Epitaxy (HWE) system. The source and substrate temperature were 630$^{\circ}C$ and 420$^{\circ}C$, respectively. The crystalline structure of single crystal thin films was investigated by the photoluminescence and double crystal X-ray diffraction (DCXD). The carrier density and mobility of CdGa$_2$Se$_4$ single crystal thin films measured from Hall erect by van der Pauw method are 8.27x10$\^$17/ cm$\^$-3/, 345 $\textrm{cm}^2$/V$.$s at 293 K, respectively. From the Photocurrent spectrum by illumination of perpendicular light on the c-axis of the CuInSe$_2$ single crystal thin film, we have found that the values of spin orbit splitting ΔSo and the crystal field splitting ΔCr were 106.5 meV and 418.9 meV at 10 K, respectively. From the photoluminescence measurement on CdGa$_2$Se$_4$ single crystal thin film, we observed free excition (E$\_$X/) existing only high quality crystal and neutral bound exiciton (D$\^$0/,X) having very strong peak intensity. Then, the full-width-at-half-maximum(FWHM) and binding energy of neutral donor bound excision were 8 meV and 13.7 meV, respectivity. By Haynes rule, an activation energy of impurity was 137 meV,

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Growth and Optoelectric Characterization of $ZnGa_{2}Se_{4}$ Sing1e Crystal Thin Films (Hot Wall Epitaxy (HWE)에 의한$ZnGa_{2}Se_{4}$단결정 박막 성장과 광전기적 특성)

  • 박창선;홍광준
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2001.11a
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    • pp.163-166
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    • 2001
  • The stochiometric mix of evaporating materials for the ZnGa$_2$Se$_4$ single crystal thin films was prepared from horizontal furnace. To obtain the single crystal thin films, ZnGa$_2$Se$_4$ mixed crystal was deposited on thoroughly etched semi-insulating GaAs(100) substrate by the Hot Wall Epitaxy (HWE) system. The source and substrate temperature were 61$0^{\circ}C$ and 45$0^{\circ}C$, respectively. The crystalline structure of single crystal thin films was investigated by the photoluminescence and double crystal X-ray diffraction (DCXD). The carrier density and mobility of ZnGa$_2$Se$_4$ single crystal thin films measured from Hall effect by van der Pauw method are 9.63x10$^{17}$ cm$^{-3}$ , 296 $\textrm{cm}^2$/V.s at 293 K, respectively, From the photocurrent spectrum by illumination of perpendicular light on the c-axis of the ZnGa$_2$Se$_4$ single crystal thin film, we have found that the values of spin orbit splitting $\Delta$So and the crystal field splitting $\Delta$Cr were 251.9 MeV and 183.2 meV at 10 K, respectively. From the photoluminescence measurement on ZnGa$_2$Se$_4$ single crystal thin film, we observed free excition (E$_{x}$) existing only high quality crystal and neutral bound excition (A$^{0}$ ,X) having very strong peak intensity. Then, the full-width-at-half-maximum(FWHM) and binding energy of neutral acceptor bound excition were 11 meV and 24.4 meV, respectivity. By Haynes rule, an activation energy of impurity was 122 meV.on energy of impurity was 122 meV.

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3-D Facial Animation on the PDA via Automatic Facial Expression Recognition (얼굴 표정의 자동 인식을 통한 PDA 상에서의 3차원 얼굴 애니메이션)

  • Lee Don-Soo;Choi Soo-Mi;Kim Hae-Hwang;Kim Yong-Guk
    • The KIPS Transactions:PartB
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    • v.12B no.7 s.103
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    • pp.795-802
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    • 2005
  • In this paper, we present a facial expression recognition-synthesis system that recognizes 7 basic emotion information automatically and renders face with non-photorelistic style in PDA For the recognition of the facial expressions, first we need to detect the face area within the image acquired from the camera. Then, a normalization procedure is applied to it for geometrical and illumination corrections. To classify a facial expression, we have found that when Gabor wavelets is combined with enhanced Fisher model the best result comes out. In our case, the out put is the 7 emotional weighting. Such weighting information transmitted to the PDA via a mobile network, is used for non-photorealistic facial expression animation. To render a 3-D avatar which has unique facial character, we adopted the cartoon-like shading method. We found that facial expression animation using emotional curves is more effective in expressing the timing of an expression comparing to the linear interpolation method.

Performance Analysis of Face Recognition by Face Image resolutions using CNN without Backpropergation and LDA (역전파가 제거된 CNN과 LDA를 이용한 얼굴 영상 해상도별 얼굴 인식률 분석)

  • Moon, Hae-Min;Park, Jin-Won;Pan, Sung Bum
    • Smart Media Journal
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    • v.5 no.1
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    • pp.24-29
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    • 2016
  • To satisfy the needs of high-level intelligent surveillance system, it shall be able to extract objects and classify to identify precise information on the object. The representative method to identify one's identity is face recognition that is caused a change in the recognition rate according to environmental factors such as illumination, background and angle of camera. In this paper, we analyze the robust face recognition of face image by changing the distance through a variety of experiments. The experiment was conducted by real face images of 1m to 5m. The method of face recognition based on Linear Discriminant Analysis show the best performance in average 75.4% when a large number of face images per one person is used for training. However, face recognition based on Convolution Neural Network show the best performance in average 69.8% when the number of face images per one person is less than five. In addition, rate of low resolution face recognition decrease rapidly when the size of the face image is smaller than $15{\times}15$.

The Planning of the Storehouse affiliated with Rural Housing for the Elderly - Focused on the Cases in Chungcheongnam-do - (농촌 고령자주택의 창고용부속사 계획 - 충청남도 지역의 사례를 중심으로 -)

  • Lee, Youn-Jae
    • Korean Institute of Interior Design Journal
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    • v.26 no.1
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    • pp.114-123
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    • 2017
  • The objective of this paper is to investigate problems associated with the storehouse affiliated with rural housing for the elderly engaged in farming activities, and to suggest improvements with the examples of storehouse floor plans. The elderly in rural area still engage in farming even though they are suffering from aging problems. Therefore, the planning of storehouse which has relevance to agriculture is very important. The methods employed were a field survey and interviews with residents. 12 houses belonging to elderly people (60's and over) were selected by the convenient sampling in Cheonan, Chungcheongnam-do. The results are as follows. First, at least more than 3 storehouses have to be planned to store the goods separatedly according to their kinds and characteristics. Second, storehouses should be placed near or directly connected with the main house to support the accessibility of the elderly. Third, the open space has to be planned in front of the storehouse to park a truck for loading goods directly. Fourth, the storage equipments such as shelves should be planned inside of the storehouse for the space efficiency and user convenience. Fifth, the width of the door should be wide enough to carry agricultural products and goods. It is recommended to use double hinged doors or double pocket doors. Besides, the thresholds of the doors should be removed and, rather than using direct lighting system, it is better to use indirect lightings and task lightings together to minimize glare and to provide enough illumination.

Real Time Eye and Gaze Tracking (실시간 눈과 시선 위치 추적)

  • 이영식;배철수
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.8 no.2
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    • pp.477-483
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    • 2004
  • This paper describes preliminary results we have obtained in developing a computer vision system based on active IR illumination for real time gaze tracking for interactive graphic display. Unlike most of the existing gaze tracking techniques, which often require assuming a static head to work well and require a cumbersome calibration process for each person our gaze tracker can perform robust and accurate gaze estimation without calibration and under rather significant head movement. This is made possible by a new gaze calibration procedure that identifies the mapping from pupil parameters to screen coordinates using the Generalized Regression Neural Networks(GRNN). With GRNN, the mapping does not have to be an analytical function and head movement is explicitly accounted for by the gaze mapping function. Futhermore, the mapping function can generalize to other individuals not used in the training. The effectiveness of our gaze tracker is demonstrated by preliminary experiments that involve gaze-contingent interactive graphic display.

LED visible light communication and their application (LED 가시광 통신시스템과 그 응용)

  • Chung, Wan-Young;Kim, Jong-Jin;Kwon, Tae-Ha
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2010.05a
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    • pp.226-229
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    • 2010
  • LED(Light Emitting Diode) is an emitting device which energy is same to the bandgap of p-type and n-type semiconductor junction. Recently high brightness LED is used in fish-luring light and traffic signal light alternative of normal light bulb, and widely used in the area of display pannel. Moreover nowadays LED has been used as a back light of LCD display. Recently, visible light communication(VLC) using LED, that allow two-way serial data communication between LEDs over a distance of sveral centimeters or meters, has been widely studied in the area of digital information transmission along with illumination and display. In this paper, we present LED communication system and their applications.

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