• Title/Summary/Keyword: $\rho$-power

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Characteristics of plasma polymerized para-xylene films as a passivation layer of organic light emitting diodes

  • Kho Sam il;Kim Min Su;Sohn Sun Young;Jung Dong Geun;Boo Jin Hyo;Jeong Seong Hoon;Park SangHee Ko
    • Journal of the Korean Vacuum Society
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    • v.14 no.4
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    • pp.195-200
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    • 2005
  • For the longevity of OLEDs, passivation of OLEDs is an important process step since organic materials used in OLEDs are very vulnerable to moisture. In this work, the passivation effect of the plasma polymerized para-xylene (PP$\rho$X) layers was studied. The PPpX layers deposited by PECVD were formed on top of the cathode with various plasma powers of 50 - 90 W. Passivation effect of PP$\rho$X was significantly dependent upon the deposition plasma power of the PP$\rho$X film. The lifetime of OLEDs with the 70 W deposited PP$\rho$X passivation layer was about 5 times longer than that of the control device.

A Study on the Optimal Design for Smart Distribution System (스마트 배전시스템의 최적 구성 방안에 관한 연구)

  • Ji, Seong-Ho;Son, Jun-Ho;Song, Seok-Hwan;Rho, Dae-Seok
    • Proceedings of the KAIS Fall Conference
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    • 2009.12a
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    • pp.834-836
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    • 2009
  • The authors have been discussed the optimal voltage regulation method and on-line real time method using artificial neural networks in the distribution system interconnected with Distributed Generation and Storage(DSG) systems. However, these methods have difficulty in dealing with the random load variations and operation characteristics of a number of DSG systems. To overcome these problems, this paper shows the basic concepts of smart grid system which is considered as one of the power delivery system in the near future and presents an evaluation method on the impacts of customer voltages by the operation of smart grid system. The smart grid system can change the system configuration in a flexible manner by using the static switches and offer the different power qualities in power services through the power quality control centers.

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A Study on the Harmonic Evaluation Algorithm for Dispersed Sources in Distribution Systems (배전계통에 있어서 분산전원의 고조파 평가 알고리즘에 관한 연구)

  • Kang, Min-Kwan;Park, Jae-Ho;Rho, Dae-Seok;Oh, Yong-Taek;Hong, Sang-Eun
    • Proceedings of the KIEE Conference
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    • 2006.07a
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    • pp.543-544
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    • 2006
  • 본 논문에서는 고조파 환경 목표레벨을 유지시키기 위하여, 고조파의 발생원인 수용가가 고조파 유출에 대한 평가 알고리즘을 제시한 것이다. 이 평가 알고리즘은 단계 별로 이루어지는데, 수용가(특수/보통)의 종류판정과 고조파 유출전류 계산 및 억제대책의 여부판정 그리고 마지막으로 고조파 대책 검토 최종 단계에 의해 역율 개선과 고조파의 발생량을 저감하기 위하여 동력변압기의 2차 측에 직렬리액터가 있는 콘덴서를 설치하고, 리액턴스를 고려 해 계산하여 유출량계산 및 상한치와 비교 후, 고조파 대책을 실시한다. 각 차 고조파에 대하여 상한치 이내로 고조파가 저감되어 기준치를 만족하면 다른 조파도 동일한 방법으로 검토한다.

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An Empirical Study on the Influence of Hypersensitiveness in Accident Reports and Usefulness on Receptiveness of Atomic Power Generation

  • Rho, Hyung-Jin
    • Journal of the Korea Society of Computer and Information
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    • v.21 no.4
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    • pp.115-121
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    • 2016
  • The purpose of this paper is to study the influence of hypersensitiveness in accident reports and usefulness on admission of atomic power generation. By the result of study we can look forward to understanding obstacles and promotion factors in constructing atomic power plants. The results of hypothesis testing can be summarized as follows: First, the hypothesis that hypersensitiveness in accident reports has a plus effect on reliability is accepted. Secondly, the hypothesis that hypersensitiveness in accident reports has a plus effect on anxiety is accepted. Thirdly, the hypothesis that reliability has a plus effect on anxiety is accepted. Fourthly, the hypothesis that reliability has a minus effect on receptiveness is accepted. Fifthly, the hypothesis that anxiety has a minus effect on receptiveness is accepted. Sixthly, the hypothesis that usefulness has a minus effect on necessity is accepted. Seventhly, the hypothesis that usefulness has a plus effect on receptiveness is rejected. Eighthly, the hypothesis that necessity has a minus effect on receptiveness is accepted.

Effect of discharge power and pressure in deposition of diamond thin films by MWPECVD (MWPECVD법에 의한 Diamond박막 성장에 있어서 방전전력과 압력의 영향)

  • Rho, Se-Yeol;Choi, Jaog-Kyu;Park, Sang-Hyun;Park, Jae-Yun;Koh, Hee-Seog
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1992.11a
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    • pp.132-135
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    • 1992
  • Diamond thin films by MWPECVD in methane-hydrogen mixed gas were studied, with emphasis on the investigation of the effect of discharge power and pressure. As a result, the growth rate of diamond thin films was affected by discharge power and the surface morphology of diamond thin films was affected by pressure. The growth rate of diamond films was about 1.65 ${\mu}m$/hr under the condition of MW power: 900W, pressure: 60torr, $H_2$ flow rate: 60sccm, $CH_4$ concentration: 1 % and deposition time: 5hr. The deposited diamond films were identified by SEM, XRD and Raman spectrophotometer.

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Control Algorithm for Wind Turbine Simulator with Variable Inertia Emulation (가변관성 모의 기능을 가진 풍력발전기 시뮬레이터의 제어 알고리즘)

  • Jeong, Byoung-Chang;Jeong, Se-Jong;Song, Seung-Ho;Rho, Do-Hwan;Kim, Dong-Yong
    • Proceedings of the KIEE Conference
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    • 2002.04a
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    • pp.170-173
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    • 2002
  • A variable speed wind turbine simulator is designed and implemented for the simulation of wind power generation system. The control algorithm decides the shaft torque delivered to generator taking into consideration the wind speed, the generator rpm, and the rotor blade inertia. It is shown that the proposed control algorithm can emulate the dynamic behavior of actual wind turbine through simulations and experimental.

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Error Rate for the Limiting Poisson-power Function Distribution

  • Joo-Hwan Kim
    • Communications for Statistical Applications and Methods
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    • v.3 no.1
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    • pp.243-255
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    • 1996
  • The number of neutron signals from a neutral particle beam(NPB) at the detector, without any errors, obeys Poisson distribution, Under two assumptions that NPB scattering distribution and aiming errors have a circular Gaussian distribution respectively, an exact probability distribution of signals becomes a Poisson-power function distribution. In this paper, we show that the error rate in simple hypothesis testing for the limiting Poisson-power function distribution is not zero. That is, the limit of ${\alpha}+{\beta}$ is zero when Poisson parameter$\kappa\rightarro\infty$, but this limit is not zero (i.e., $\rho\ell$>0)for the Poisson-power function distribution. We also give optimal decision algorithms for a specified error rate.

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A Study on the Evaluation Algorithm for Dispersed Generations in Distribution Systems (분산형전원의 배전계통 연계 해석 알고리즘에 관한 연구)

  • Kang Min-Kwan;Rho Dae-Seok;Oh Yong-Taek;Hong Sangeun
    • Proceedings of the KAIS Fall Conference
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    • 2005.05a
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    • pp.231-233
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    • 2005
  • 국가차원의 신$\cdot$재생에너지 활성화 방안에 따라 지자체 등의 분산형전원 시설계획이 점차 증가하고 있으나, 아직 우리나라에는 분산형전원의 계통연계에 대한 체계적인 기술지침이 초기 단계에 있거나 제정 중에 있어서, 계통연계와 관련하여 발전사업자와 전력회사간의 이 해가 상충되는 등 문제점이 발생되고 있다. 현재 분산형전원 단지의 도입계획은 비교적 많은 반면에 이에 대한 해석방법과 기술적인 평가방안이 구체적으로 제시되어 있지 않아, 설치자(시도 및 지자체)와 각 배전지사에서 많은 혼돈과 어려움을 려고 있는 실정이다. 따라서 본 논문에서는 태양광, 풍력 등의 분산형전원이 배전계통에 도입되는 경우, 기술적인 평가 알고리즘을 제시하고자 한다.

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A USING LON CHIP FEEDER CONTROL FOR THE SMT MOUNTER (LON CHIP을 이용한 SMT MOUNTER의 FEEDER CONTROL)

  • Lim Eung-Kyu;Rho Sung-Chan;Kim Yoon-Ho
    • Proceedings of the KIPE Conference
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    • 2001.07a
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    • pp.167-171
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    • 2001
  • In PCB assembling line, it needs SMD mounter. In this paper, the feeder of the SMD mounter, which carry component to the mounter is designed. Up to now, mechanical air feeder is mainly used. But in these days, it is developed to the electrical feeder with network. There are many kind of feeders with various control technique. In this paper, the feeder with BLDC motor and LON chip is designed and implemented. Then the experimental results are presented.

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Electrical Transport Properties of LaNi1-xTixO3(x∼0.5) Ceramics (LaNi1-xTixO3(x∼0.5) 세라믹스의 전기전도 특성)

  • Jung, Woo-Hwan
    • Korean Journal of Materials Research
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    • v.19 no.4
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    • pp.186-191
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    • 2009
  • Thermoelectric power and resistivity are measured for the perovskite $LaNi_{1-x}Ti_xO_3$ ($x{\leq}0.5$) in the temperature range 77 K - 300 K. The measured thermoelectric power of $LaNi_{1-x}Ti_xO_3$ ($x{\leq}0.5$) increases linearly with temperature and is represented by A + BT. The x = 0.1 sample showed metallic behavior, the x = 0.3 showed metal and insulating transition around 150 K, and x = 0.5 showed insulating behavior the over the whole temperature range. The electrical resistivity of x = 0.1 shows linear temperature dependence over the whole temperature range and $T^2$ dependence. On the other hand, the electrical resistivity of x = 0.3 shows a linear relation between $ln{\rho}$ and $T^{-1/4}$ (variable range hopping mechanism) in the range of 77 K to 150 K. For x = 0.5, the temperature dependence of resistivity is characteristic of insulating materials; the resistivity data was fitted to an exponential law, such as ln(${\rho}/T$) and $T^{-1}$, which is usually attributed to a small polaron hopping mechanism. These experimental results are interpreted in terms of the spin polaron (x = 0.1) and variable range hopping (x = 0.3) or small polaron hopping (x = 0.5) of an almost localized $Ni^{3+}$ 3d polaron.