• Title/Summary/Keyword: Step pulse

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Technical Development of Flue Gas Control at Commercial Plant Using the Non-thermal Plasma Process (저온 플라즈마 공정을 이용한 상용설비의 배연가스 처리 기술개발)

  • Yoo, J.S.;Paek, M.S.;Kim, T.H.;Kim, J.I.;Kim, Y.S.;Choi, S.H.
    • Proceedings of the KSME Conference
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    • 2001.06d
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    • pp.939-944
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    • 2001
  • For the application of simultaneous $DeSO_{2}\;&\;DeNO_{x}$ equipment using non-thermal plasma process to the industrial and power plants, the many types of plasma device and process were studied. The e-beam and pulsed plasma corona discharge process are outstanding for the study to apply commercial large-scale plant from among these. In this paper, non-thermal plasma of technical trends and the characteristics of system developed by Doosan heavy industries & construction Co., Ltd. are explained. We have researched pulsed plasma corona discharge process since 1994. At the basis of reasonable results for the pilot plant, we constructed the demonstration plant at a domestic coal-fired power plant in 1999, as the previous step for commercial use. In near future, enough information about designs and costs of commercial-size system will be obtained.

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Luminance Control for given gray level by the Asymmetric Sustain Pulse in ac PDP

  • Choi, Joon-Young;Choi, In-Ju;Park, Mi-Young;Lee, Ho-Jun;Lee, Hea-Jun;Kim, Dong-Hyun;Park, Chung-Hoo
    • 한국정보디스플레이학회:학술대회논문집
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    • 2004.08a
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    • pp.171-175
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    • 2004
  • Need of a dimmer function becomes more important with increasing interest on a HDTV for home theater applications. In a conventional ac PDP, a possible method to reduce luminance of a whole panel is to reduce a total number of sustain pulses and then to change the gray level. However, the reduction of the total sustain number causes the step of luminance to be rough Moreover, it is impossible to control the luminance of the panel for a given gray level. In this paper, a simple and robust method is proposed to control linearly the luminance of whole panel by applying the asymmetric sustain pulses in the display period of the ADS driving scheme. As the range of luminance control by the proposed method is about 50% for a given gray level. Moreover, it is experimentally verified that the proposed method shows similar dynamic margin performances compare with the conventional method.

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A Study on the Development of a Lightning Warning System by the Measurement of Electric Field at the Ground (용량성 프로브와 광전송회로를 이용한 광대역 전압측정장치)

  • Kil, Gyung-Suk;Song, Jae-Yong;Park, Dae-Won
    • Journal of Sensor Science and Technology
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    • v.13 no.5
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    • pp.363-368
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    • 2004
  • A reliable voltage measurement system is necessary to monitor status of power facilities in substations, which is easy to set up and is not influenced by electromagnetic interference in and around substation. In this paper, we described a voltage measurement system (VMS) which is composed of a capacitive voltage probe, an impedance converter, and an optical linker. To get a wide-band characteristic of the VMS, a high speed impedance converter was used, and the output impedance of the VMS was set at $50{\Omega}$ to match any types of observing instruments. The frequency bandwidth of the VMS. which was estimated by a step pulse, was ranges from 11.42 Hz to 13.65 MHz, and the VMS showed a good response characteristic in a high frequency domain such as impulse voltages as well as a commercial frequency voltage.

A Study on the Low Force Estimation of Skeletal Muscle by using ICA and Neuro-transmission Model (독립성분 분석과 신전달 모델을 이용한 근육의 미세한 힘의 추정에 관한 연구)

  • Yoo, Sae-Keun;Youm, Doo-Ho;Lee, Ho-Yong;Kim, Sung-Hwan
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.56 no.3
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    • pp.632-640
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    • 2007
  • The low force estimation method of skeletal muscle was proposed by using ICA(independent component analysis) and neuro-transmission model. An EMG decomposition is the procedure by which the signal is classified into its constituent MUAP(motor unit action potential). The force index of electromyography was due to the generation of MUAP. To estimate low force, current analysis technique, such as RMS(root mean square) and MAV(mean absolute value), have not been shown to provide direct measures of the number and timing of motoneurons firing or their firing frequencies, but are used due to lack of other options. In this paper, the method based on ICA and chemical signal transmission mechanism from neuron to muscle was proposed. The force generation model consists of two linear, first-order low pass filters separated by a static non-linearity. The model takes a modulated IPI(inter pulse interval) as input and produces isometric force as output. Both the step and random train were applied to the neuro-transmission model. As a results, the ICA has shown remarkable enhancement by finding a hidden MAUP from the original superimposed EMG signal and estimating accurate IPI. And the proposed estimation technique shows good agreements with the low force measured comparing with RMS and MAV method to the input patterns.

The Experiment of High Voltage Capacitor Charger for Pulsed Power Application (펄스전원용 고압커패시터 충전기 시험)

  • Jang, S.R.;Ahn, S.H.;Ryoo, H.J.;Kim, J.S.;Kim, Y.B.;Kim, J.S.;Lee, B.H.;Kim, S.H.
    • Proceedings of the KIEE Conference
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    • 2009.07a
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    • pp.1025_1026
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    • 2009
  • This paper introduces the test a rapid pulsed power charging system for pulsed power application. The charger is designed based on three-phase series resonant inverter followed by air cooled step-up transformers. It has many advantages of lower weight, small size and high efficiency compared with large bulky traditional pulse power charging system. To apply 150kJ pulsed power system, detail test was carried out at various condition and its results shows 90% efficiency at full load condition. And additional experiments such as short, open, and self discharging during charging status are performed to verify reliable operation at abnormal condition and it was confirmed that developed capacitor charger showed very reliable operation all over the tests.

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The Characterization of the Increase of Membrane Conductance after Depolarization in Single Rat Adrenal Chromaffin Cells

  • Lim, Won-Il;Kim, Sang-Jeong;Kim, Jun
    • The Korean Journal of Physiology and Pharmacology
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    • v.2 no.1
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    • pp.95-100
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    • 1998
  • The conductance change evoked by step depolarization was studied in primarily cultured rat adrenal chromaffin cells using patch-clamp and capacitance measurement techniques. When we applied a depolarizing pulse to a chromaffin cell, the inward calcium current was followed by an outward current and depolarization-induced exocytosis was accompanied by an increase in conductance trace. The slow inward tail current which has the same time course as the conductance change was observed in current recording. The activation of slow tail current was calcium-dependent. Reversal potentials agreed with Nernst equation assuming relative permeability of $Cs^+\;to\;K^+$ is 0.095. The outward current and tail current were blocked by apamin (200 nM) and d-tubocurarine (2 mM). The conductance change was blocked by apamin and did not affect membrane capacitance recording. We confirmed that conductance change after depolarization comes from the activation of the SK channel and can be blocked by application of the SK channel blockers. Consequently, it is necessary to consider blocking of the SK channel during membrane capacitance recording.

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Guideline Development to Evaluate the Safety and Performance of Intense Pulsed Light(IPL) (Intense Pulsed Light의 안전성 및 성능평가를 위한 시험 항목 및 시험방법(안) 연구)

  • Kang, Dong-Yeon;Son, Tae-Yoon;Joo, Yea-Il;Choi, Eung-Ho;Jung, Byung-Jo
    • Journal of Biomedical Engineering Research
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    • v.31 no.2
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    • pp.129-133
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    • 2010
  • Intense pulsed light(IPL) is a photo-therapeutic medical device using xenon lamps with optical characteristics of incoherence, defocusing, and polychromatic. IPL has been recognized as a representative medical therapeutic device with growth of domestic skin care market. However, there is no standard regulation manual and guideline to evaluate the safety and performance of IPL. International Electrotechnical Commission(IEC) is being statued "Technical Report IEC TR 60825-16" which is a guidelines for the safe use of intense light source equipment on humans and animals. In this study, a standard Korea Food & Drug Administration (KFDA) regulation for the safety and performance of IPL was suggested by developing minimal evaluation methods for optical parameters of IPL such as output energy density, pulse mode, spot size, wavelength and uniformity of output light. We expect that this study may be a step to statue a standard regulation manual and guideline for IPLs used in domestic.

COMMON SHRIMP BEHAVIOUR TO PHYSICAL STIMULI AND THE FISHING GEAR DESIGN (II) (물리적 자극에 대한 보리새우의 행동과 어구 설계(II))

  • KO Kwan Soh;KIM Sang-Han
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.4 no.1
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    • pp.1-6
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    • 1971
  • In order to study the catching efficiency of shrimp trawl equipped with electrodes around the net mouth and stimulant devices attached to the ground rope, an experimental operation was carried out at Oma-Island Shrimp Farm from October 3rd to November 5th, 1970. Many studies have been made on the shrimp trawl with electric stimulant devices, but few can be found for detailed scientific catching methods. Electric power consumption was so excessive that electric stimulant devices could not be developed for commercial purposes. As a first step toward the successive operations of the electric stimulant devices in the field, it is necessary to study fundamental principles, such as electric current, voltage, electric potential, potential difference, electric field and suitable pulse. The behaviour response of the common shrimp, Penaeus japonicus BATE to moving nets and electric stimulant devices were reported in the preceding papers based on the water tank experiments (Ko and Kim, 1970). Through comparative fishing tests the rate of catching efficiency during daylight time was confirmed to be from 89 to 96 per cent of the night catch efficiency, and with 30 V. 1.5 A. electric power was sufficent for practical sea operation.

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Stabilizing Control of DC/DC Buck Converters with Constant Power Loads in Continuous Conduction and Discontinuous Conduction Modes Using Digital Power Alignment Technique

  • Khaligh Alireza;Emadi Ali
    • Journal of Electrical Engineering and Technology
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    • v.1 no.1
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    • pp.63-72
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    • 2006
  • The purpose of this raper is to address the negative impedance instability in DC/DC converters. We present the negative impedance instability of PWM DC/DC converters loaded by constant power loads (CPLs). An approach to design digital controllers for DC/DC converters Is presented. The proposed method, called Power Alignment control technique, is applied to DC/DC step-down choppers operating in continuous conduction or discontinuous conduction modes with CPLs. This approach uses two predefined state variables instead of conventional pulse width modulation (PWM) to regulate the output voltage. A comparator compares actual output voltage with the reference and then switches between the appropriate states. It needs few logic gates and comparators to be implemented thus, making it extremely simple and easy to develop using a low-cost application specific integrated circuit (ASIC) for converters with CPLs. Furthermore, stability of the proposed controllers using the small signal analysis as well as the second theorem of Lyapunov is verified. Finally, simulation and analytical results are presented to describe and verify the proposed technique.

Ru and $RuO_2$ Thin Films Grown by Atomic Layer Deposition

  • Shin, Woong-Chul;Choi, Kyu-Jeong;Jung, Hyun-June;Yoon, Soon-Gil;Kim, Soo-Hyun
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2008.11a
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    • pp.149-149
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    • 2008
  • Metal-Insulator-Metal(MIM) capacitors have been studied extensively for next generation of high-density dynamic random access memory (DRAM) devices. Of several candidates for metal electrodes, Ru or its conducting oxide $RuO_2$ is the most promising material due to process maturity, feasibility, and reliability. ALD can be used to form the Ru and RuO2 electrode because of its inherent ability to achieve high level of conformality and step coverage. Moreover, it enables precise control of film thickness at atomic dimensions as a result of self-limited surface reactions. Recently, ALD processes for Ru and $RuO_2$, including plasma-enhanced ALD, have been studied for various semiconductor applications, such as gate metal electrodes, Cu interconnections, and capacitor electrodes. We investigated Ru/$RuO_2$ thin films by thermal ALD with various deposition parameters such as deposition temperature, oxygen flow rate, and source pulse time. Ru and $RuO_2$ thin films were grown by ALD(Lucida D150, NCD Co.) using RuDi as precursor and O2 gas as a reactant at $200\sim350^{\circ}C$.

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