• Title/Summary/Keyword: light guide

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Study on the Standard Specification of Linear Induction Motor Type Light Rail Vehicle Electrical Equipment (선형유도모터형식 경전철 전기장치 표준사양 연구)

  • Cho, Hong-Shik;Lee, Ho-Yong;Cho, Bong-Kwan;Hong, Jai-Sung;Ryu, Sang-Whan
    • Proceedings of the KIEE Conference
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    • 2007.07a
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    • pp.1181-1182
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    • 2007
  • Light Rail Transit (LRT) System is an urban transit system which has approximately an intermediate transportation capacity between conventional subway and bus ($5,000{\sim}25,000$ persons per hour and per direction). It is a high-tech system which operational capacity, punctuality and mobility are remarkably improved. There are some types of LRT systems such as monorail, tramway, AGT(Automated Guideway Transit), and so on. The LRT systems have been applied and being operated in about a hundred lines around the world and many projects that apply the LRT systems in Korea are being proceeded and scheduled. For the efficient management, economical construction, and safe operation of various LRT systems, the establishment of national standard is necessary such as vehicle standardized specification, vehicle performance test standard, vehicle safety standard, construction guide, operation regulation, etc. of LRT systems. This paper presents the standard specification of electrical equipment of linear induction motor type light rail vehicle, that is LIM AGT(AGT system propelled with linear induction motor) vehicle. The LIM AGT system has been applied in Japan subway and ART(Advanced Rapid Transit) system of Canada and Yongin LRT is currently under construction.

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The Study of Prism-Patternde Light Guide Plate for increase of efficiency in Monitor Back Light Unit (MNT BLU의 효율 향상을 위한 프리즘 도광판에 대한 연구)

  • Park, Doo-Sung;Lee, Mi-Sun;Park, Ki-Duck;Oh, Young-Sik;Kim, Seo-Yoon;Lim, Young-Jin
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2005.07a
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    • pp.502-503
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    • 2005
  • 본 연구에서는 TFT-LCD(Thin Film Transistor-Liquid Crystal Display)의 배경광원인 BLU(Back Light Unit)의 고효율화, 고품질화를 통한 원가 절감을 달성하기 위해 BLU의 대표적 핵심부품중에 하나인 프리즘 시트를 사용하지 않는 구조의 MNT용 BLU를 개발하는데 목적을 두었다. 고효율의 BLU를 만들기위하여 17인치 BLU의 도광판의 상, 하면에 Prism 형상을 구현하였으며, 광학적 시뮬레이션을 통하여 먼저 가능성을 검토하였고, UV에 반응하는 Resin을 경화시키는 방법을 이용하여 일반 도광판에 프리즘형상을 각인(Imprint)시키는 방법으로 실물을 재현하였다. 실험 결과 프리즘 시트를 사용하지 않는 구조의 MNT용 17인치 BLU에서 중심휘도 4,984nit, 균일도 70% 달성하였다.

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Surface Plasmon Effect in Hot Electron Based Photovoltaic Devices

  • Lee, Yeong-Geun;Jeong, Chan-Ho;Park, Jong-Hyeok;Park, Jeong-Yeong
    • Proceedings of the Korean Vacuum Society Conference
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    • 2011.08a
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    • pp.162-162
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    • 2011
  • Nanometer-sized noble metals can trap and guide sunlight for enhanced absorption of light based on surface plasmon that is beneficial for generation of hot electron flows. A pulse of high kinetic energy electrons (1-3 eV), or hot electrons, in metals can be generated after surface exposure to external energy, such as in the absorption of light or in exothermic chemical processes. These energetic electrons are not at thermal equilibrium with the metal atoms. It is highly probable that the correlation between hot electron generation and surface plasmon can offer a new guide for energy conversion systems [1-3]. We show that hot electron flow is generated on the modified gold thin film (<10 nm) of metal-semiconductor (TiO2) Schottky diodes by photon absorption, which is amplified by localized surface plasmon resonance. The short-circuit photocurrent obtained with low energy photons (lower than bandgap of TiO2, ~3.1-3.2 eV) is consistent with Fowler's law, confirming the presence of hot electron flows. The morphology of the metal thin film was modified to a connected gold island structure after heating to 120, 160, 200, and 240$^{\circ}C$. These connected island structures exhibit both a significant increase in hot electron flow and a localized surface plasmon with the peak energy at 550-570 nm, which was separately characterized with UV-Vis [4]. The result indicates a strong correlation between the hot electron flow and localized surface plasmon resonance with possible application in hot electron based solar cells and photodetectors.

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Simulation and Experimental Study on the Impact of Light Railway Train Bridge Due to Concrete Rail Prominence (주행면 단차에 의한 경량전철 교량의 충격 시뮬레이션 및 실험)

  • Jeon, Jun-Tai;Song, Jae-Pil
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.30 no.1A
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    • pp.45-52
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    • 2010
  • This study pointed on the dynamic impact of AGT (Automated Guide-way Transit) bridge, due to concrete rail prominence. An experiment was done with 30 m P.S.C. bridge in AGT test line in Kyungsan. An artificial prominence with 10 mm hight, was installed at the mid span of concrete rail. And computer simulation was executed for the artificial prominence. As an experiment result, in the case of with prominence, bridge acceleration responses are increased 50% at the speed range of 20 km/h-60 km/h, and bridge displacement responses increased slightly. With these results, the prominence of concrete rail can be induce excess impact and vibration. And the computer program simulated much the same as experiments. So this program can be used for AGT bridge design and formulate the standard of concrete rail management.

Monte Carlo Simulations of Detection Efficiency and Position Resolution of NaI(TI)-PMT Detector used in Small Gamma Camera (소형 감마카메라 제작에 사용되는 NaI(TI)- 광전자증배관 검출기의 민감도와 위치 분해능 특성 연구를 위한 몬테카를로 시뮬레이션)

  • Kim, Jong-Ho;Choi, Yong;Kim, Jun-Young;Im, Ki-Chun;Kim, Sang-Eun;Choi, Yeon-Sung;Joo, Kwan-Sik;Kim, Young-Jin;Kim, Byung-Tae
    • Progress in Medical Physics
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    • v.8 no.2
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    • pp.67-76
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    • 1997
  • We studied optical behavior of scintillation light generated in NaI(TI) crystal using Monte Carlo simulation method. The simulation was performed for the model of NaI(TI) scintillator (size: 60 mm ${\times}$ 60 mm ${\times}$ 6 mm) using an optical tracking code. The sensitivity as a function of surface treatment (Ground, Polished, Metal-0.95RC, Polished-0.98RC, Painted- 0.98RC) of the incident surface of the scintillator was compared. The effects of NaI(TI) scintillator thickness and the refractive index of light guide optically coupling between the NaI(TI) scintillator and photomultiplier tube (PMT) were simulated. We also evaluated intrinsic position resolution of the system by calculating the spread of scintillation light generated. The sensitivities of the system having the surface treatment of Ground, Polished, Metal-0.95RC, Polished-0.98RC and Painted-0.98RC were 70.9%, 73.9%, 78.6%, 80.1% and 85.2%, respectively, and the surface treatment of Painted-0.98RC allowed the highest sensitivity. As increasing the thickness of scintillation crystal and light guide, the sensitivity of the system was decreased. As the refractive index of light guide increases, the sensitivity was increased. The intrinsic position resolution of the system was estimated to be 1.2 mm in horizontal and vertical directions. In this study, the performance of NaI(TI)-PMT detector system was evaluated using Monte Carlo simulation. Based on the results, we concluded that the NaI(TI)-PMT detector array is a favorable configuration for small gamma camera imaging breast tumor using Tc-99m labeled radiopharmaceuticals.

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Behavioral characteristics of a chondrostean sturgeon species Acipenser baerii prelarvae in response to different environmental light intensities in a diel photoperiodic cycle

  • Kim, Eun Jeong;Park, Chulhong;Nam, Yoon Kwon
    • Journal of Animal Reproduction and Biotechnology
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    • v.35 no.3
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    • pp.245-257
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    • 2020
  • Behavioral response to a diel photoperiodicity (500 lx for 16 h, 5 lx for 4 h and < 0.5 lx for 4 h) and phototactic characteristics in dark conditions were examined with Siberian sturgeon Acipenser baerii (Chondrostei, Actinopterygii) prelarvae. Siberian sturgeon prelarvae represented both qualitative and quantitative changes in their behavioral patterns according to different light intensities in a diel photoperiodicity. Under daylight conditions (500 lx), prelarvae displayed saltatory changes of behavioral features with ages (Day 0-Day 9) in a general order of swimming-up/drifting, swimming in the upper water column, benthic swimming with rheotaxis, schooling and post-schooling behavior. Compared to daylight conditions, prelarvae tended to show more benthic performances and quantitative reductions of schooling and post-schooling behaviors under dimlight conditions (5 lx). Under dark conditions (< 0.5 lx), prelarvae exhibited a fairly uniform behavioral pattern characterized by the benthic swimming across the bottom of the tank. From phototaxis tests under dark conditions, navigational responses of prelarvae to a spotlight illumination were quantitatively changed as their ages increased. The phototactic responses reached the peak on Day 2, continued until Day 4, and then gradually decreased until Day 8. A partial recovery of positive phototaxis was observed on Day 9. Data from this study suggest that the diel light cycle as well as the light intensity of each interval in the cycle should be considered as important components of a practical guide for evaluating fitness and developmental states of artificially propagated Siberian sturgeon prelarvae.

A Study on the Effective Maintenance Method of the Stair Passage Leading Light installed In the Shopping Building (상가건물 계단통로유도등의 유지관리 효율화 방안에 관한 연구)

  • Lee, Young-Sam
    • Journal of the Korea Safety Management & Science
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    • v.18 no.1
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    • pp.1-8
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    • 2016
  • This study was conducted by survey and inspection of stair passage leading lights in shopping buildings which are more than 5 stories and have an underground parking lot located at Pyeongtaek-si and Seongnam-si. Number of shopping building for this study is 30 and of stair passage leading light inspected by two lights in each shopping building is 60. The result of this study is that the type of installed leading lights is LED(77%), and 60% of leading lights has problem such as no cleaning, scratch and discoloration, etc. The height of installed leading lights meets the fire law which is less than 1m from the floor. Visible condition of leading lights is good except some leading lights which have a little visible problem due to banner advertisement. 37% of standby power has flickered and went out. 93% of total leading lights meets the fire law which is more than 1lux from 0.5m distance, but cold cathode fluorescent lamps(CCFLs) have the problem which not meets proper brightness level based on fire law. In additional measurement result, zero lux of leading lights is 32%(from 1m distance), 68%(from 1.5m distance) and 98%(from 2m distance). Leading light is very important facility because it is eyes and guide when emergency. Therefore, proper fire facility operating function inspection and total detailed inspection are important to keep the good condition of leading light except simple visual check, and also improvement in law system of type approval, fire construction inspection and illumination level will be needed.

Film Image Transfer System (FITS): An Efficient Method for Proper Positioning of Orthodontic Mini-implants

  • Go, Taek-Su;Kim, Seong-Hun;Nelson, Gerald
    • Journal of Korean Dental Science
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    • v.4 no.1
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    • pp.20-25
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    • 2011
  • Purpose: To describe the newly developed Film image transfer system (FITS) for proper positioning of the orthodontic mini-implant in the narrow interdental space and considerations for better application. Materials and Methods: A patient who was planning to have orthodontic mini-implant treatment on the posterior maxilla was recruited to assess the feasibility of FITS. Dental radiographic film and bite record was taken. And then the film image was transferred on the photographic emulsion coated model using transfer light through film projector (enlarger). After exposing the photo emulsion coating on the model, the image was developed with a working solution for a paper developer and fixed. The surgical guide for the mini-implant was fabricated from the transported FITS data. Results: The completed surgical guide was easily placed intraorally, and allowed a simple and rapid placement of the mini-implant. The site of the implant placement was accurate as planned position. Conclusion: In the reported case, The FITS technique represents an effort to minimize risk to the patient and produce consistently good results based upon accurate information about the anatomy of the implant site.

Power Splitting of Plasmonic Directional Couplers with Nano-scale Three Channels (나노 크기의 세 채널 플라즈마 방향성 결합기의 전력분배)

  • Ho, Kwang-Chun
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.11 no.3
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    • pp.47-52
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    • 2011
  • Directional couplers based on plasmonic waveguides with nano-scale three channels are designed by utilizing mode coupling effect as well as rib-guiding structure. Longitudinal modal transmission-line theory(L-MTLT) is used for simulating the light propagation and optimizing the design parameters. The designed plasmonic coupler operating as power splitter has nano-scale size of about 200~250 nm width. In order to achieve the desired power splitting ratio, the refractive index of guiding modes is evaluated along the width variation of center channel. Finally, a power splitter based on triple rib directional coupler, which ensures maximum power transfer from one outermost guide to the other outermost guide, is designed.

A Study on UI of Space Culture Hand Carry Guide Contents (휴대용 공간문화 안내 콘텐츠 UI에 관한 연구)

  • Lee, Seongryeong;Choi, Seung-soo;Kim, Jinwook;Goh, Ildu
    • Proceedings of the Korea Contents Association Conference
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    • 2008.05a
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    • pp.796-799
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    • 2008
  • The hand carry digital media appliances is going to use widely, because the machines became to be small size and light weight for easy carry. Also the demand of various contents was increased for small personal media player:PMP. Now a day PMP was used as a private leisure instruments and will be used as active digital tools like a space culture guiding tools. In this research we will study on the development of user interface for space culture guide contents. Especially we proposed checking tools to be used in test and development phase of UI design for small display appliances.

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