• Title/Summary/Keyword: photo current

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Etch characteristics of Pb(Zr,Ti)$O_3$ by using HBr/Ar gas mixtures (HBr/Ar 가스를 이용한 Pb(Zr,Ti)$O_3$ 식각 특성 연구)

  • Kim, Young-Keun;Son, Hyun-Jin;Lee, Seung-Hun;Kwon, Kwang-Ho
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2010.06a
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    • pp.340-340
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    • 2010
  • 본 연구에서는 유도결합형 플라즈마(ICP)를 이용하여, HBr/Ar 가스의 조성비 변화에 따른 Pb(Zr,Ti)$O_3$ 박막에 대한 식각특성을 연구 하였다. PZT박막의 식각속도와 Oxide($SiO_2$), Photo resister(PR)에 대한 식각선택비를 추출하였으며, 식각 메카니즘을 규명하기 위하여 optical emission spectroscopy(OES)와 double Langmuir prove(DLP) 이용하여 라디칼 특성변화와 이온 전류밀도(Ion current density)를 측정하였다.

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System Development for Education and Design of a Nonlinear Controller with On-Line Algorithm

  • Park, Seong-Wook
    • International Journal of Control, Automation, and Systems
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    • v.1 no.2
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    • pp.215-221
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    • 2003
  • The education system in this paper is used to demonstrate and educate the effects of electromagnetic induction. Placing an aluminum ring over the core and switching on AC source causes the ring to jump in the air due to induced currents in the ring producing a magnetic field opposed to that produced in the core. To control the position of the ring by only the current, it is to require nonlinear control algorithm and control board that is composed of photo sensors, decode circuit, computer communication, and power electronics circuit. This paper provides the development for education system in detail and the effects of dynamic neural networks for nonlinear control with on line is studied.

A Versatile Design of Optronic Negative Resistance (호용성이 있는 광결합 부성저항회로의 설계)

  • 박성한
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.15 no.4
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    • pp.33-37
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    • 1978
  • A versatile negative resistance using one transistor, one photo-coupler and three resisters, which can be used as either a voltage controlled or current controlled negative resistance, is designed. The versatility is obtained by changing the transistor and one connection of the circuit. The negative resistance region is linear and its value can be varied by varying one of the three resistor values.

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External Cavity Lasers Composed of Higher Order Gratings and SLDs Integrated on PLC Platform

  • Shin, Jang-Uk;Oh, Su-Hwan;Park, Yoon-Jung;Park, Sang-Ho;Han, Young-Tak;Sung, Hee-Kyung;Oh, Kwang-Ryong
    • ETRI Journal
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    • v.29 no.4
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    • pp.452-456
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    • 2007
  • Very compact 4-channel 200-GHz-spacing external cavity lasers (ECLs) were fabricated by hybrid integration of reflection gratings and superluminescent laser diodes on a planar lightwave circuit chip. The fifth-order gratings as reflection gratings were formed using a conventional contact-mask photo-lithography process to achieve low-cost fabrication. The lasing wavelength of the fabricated ECLs matched the ITU grid with an accuracy of ${\pm}0.1$ nm, and optical powers were more than 0.4 mW at the injection current of 80 mA for all channels. The ECLs showed single mode operations with more than 30 dB side lobe suppression.

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Scientific Visualization of Oceanic Data (GIS정보를 이용한 해양자료의 과학적 가시화)

  • Im, Hyo-Hyuc;Kim, Hyeon-Seong;Han, Sang-Cheon;Seong, Ha-Keun;Kim, Kye-Yeong
    • Proceedings of the Korean Society of Marine Engineers Conference
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    • 2006.06a
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    • pp.195-196
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    • 2006
  • Recently, there are increasing need to make a synthetic assessment about oceanic data which is collected over the various scientific field, in addition to just gathering oceanic data. In this study, we made a basic map using satellite image, aerial photo, multi-beam data, geological stratum data etc. And as well we are producing comprehensive SVT(Scientific Visualization Toolkit) which can visualize various kinds of oceanic data. These oceanic data include both survey data such as tidal height, tide, current, wave, water temperature, salinity, oceanic weather data and numeric modelling results such as ocean hydrodynamic model, wave model, erosion/sediment model, thermal discharged coastal water model, ocean water quality model. In this process, we introduce GIS(Geographic Information System) concepts to reflect time and spatial characteristics of oceanic data.

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Gamma-ray Detectors for Nuclear Medical Imaging Instruments (핵의학 영상기기의 감마선 검출기)

  • Cho, Gyu-Seong
    • Nuclear Medicine and Molecular Imaging
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    • v.42 no.2
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    • pp.88-97
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    • 2008
  • In this review paper, basic configurations of gamma detectors in SPECT and PET systems were reviewed together with key performance parameters of the imaging system, such as the detection efficiency, the spatial resolution, the contrast resolution, and the data acquisition time for quick understanding of the system-component relationship and future design of advanced systems. Also key elements of SPECT and PET detectors, such as collimators, gamma detectors were discussed in conjunction with their current and future trend. Especially development trend of new scintillation crystals, innovative silicon-based photo-sensors and futuristic room-temperature semiconductor detectors were reviewed for researchers who are interested in the development of future nuclear medical imaging instruments.

DISCRIMINATING MAJOR SPECIES OF TREE IN COMPARTMENT FROM OPTIC IMAGERY AND LIDAR DATA

  • Hong, Sung-Hoo;Lee, Seung-Ho;Cho, Hyun-Kook
    • Proceedings of the KSRS Conference
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    • 2008.10a
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    • pp.41-44
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    • 2008
  • In this paper, major species of tree were discriminated in compartment by using LiDAR data and optic imagery. This is an important work in forest field. A current digital stock map has created the aerial photo and collecting survey data. Unlike high resolution imagery, LiDAR data is not influenced by topographic effects since it is an active sensory system. LiDAR system can measure three dimension information of individual tree. And the main methods of this study were to extract reliable the individual tree and analysis techniques to facilitate the used LiDAR data for calculating tree crown 2D parameter. We should estimate the forest inventory for calculating parameter. 2D parameter has need of area, perimeter, diameter, height, crown shape, etc. Eventually, major species of tree were determined the tree parameters, compared a digital stock map.

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Design and Manufacturing Factors of Micro-via Buildup Substrate Technology

  • Tsukada, Yutaka
    • Proceedings of the International Microelectronics And Packaging Society Conference
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    • 2001.09a
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    • pp.183-192
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    • 2001
  • 1- Buildup PCB technology is utilized to a bare chip attach substrate technology for packaging of semiconductor chip 2- Requirement for the substrate design rule is described in SIA International Technology Roadmap for Semiconductor. 3- There are seven fabrication methods of build-up technology. 4- Coating and lamination for resin and photo, and laser for micro via hope processes are available. Below $50\mu\textrm{m}$ in diameter is possible. 5- Fine pitch lines down to $30\mu\textrm{m}$ can be achieved by pattern plating with better electrical property. 6- Dielectric loss reduction is a key material improvement item for next generation build-up technology. 7- High band width up to 512 GB/s is possible with current wiring groundrule.

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A Study on the Removal of SOx/NOx by a Pulsed Corona Discharge in the Wire-Plate Reactor (Wire-Plate 반응기에서 펄스 코로나 방전을 이용한 탈황 탈질에 관한 연구)

  • Shin, Wan-Ho;Song, Yong-Hoon;Kim, Han-Seok;Choi, Yeon-Seok;Kim, Seok-Joon
    • Proceedings of the KIEE Conference
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    • 1996.07c
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    • pp.1910-1912
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    • 1996
  • This paper presents the results of laboratory experimentals to remove $SO_2$ and $NO_x$ by a pulsed corona discharge in the wire-plate reactor. A rotating spark gap switch was used to generate the pulse by chewing the dc high voltage. Repetition frequency of the pulse was 60Hz and rising time of 50ns. The photo pictures of positive streamer corona taken by ICCD camera, pulse voltage and current were measured using a digital oscilloscope. Simultaneous effects of $C_{2}H_{4}$ injection and heterogeneous chemical reactions on nonthermal plasma process to remove $SO_2$ and $NO_x$ from flue gas were investigated in the present study

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Characterization of TiO2 Nanocrystalline Films for High Performance Dye-Sensitized Solar Cells

  • Jung, Heung-Joe
    • Transactions on Electrical and Electronic Materials
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    • v.12 no.3
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    • pp.123-126
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    • 2011
  • Titanium dioxide ($TiO_2$) thin films were deposited by the sol-gel method with a surfactant-assisted mechanism. Its application for dye-sensitized solar cells (DSSCs) was investigated. Brunauer-Emmett-Teller, X-ray diffraction and field emission scanning electron microscopy techniques were used to characterize the surface characteristics of thin films. Photovoltaic-current density measurements were performed to determine the photoelectrochemical properties of the thin films and the performance of DSSCs. Energy conversion efficiency of about 6.1% was achieved for cells with conductive glass under illumination with AM 1.5 (100 $mWcm^{-2}$) simulated sunlight. Investigation showed higher photo-energy conversion efficiency for mesoporous $TiO_2$ nanocrystalline films used in DSSCs relative to commercially available Degussa P25 films.