• Title/Summary/Keyword: Mod

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Effects of organic additives on YBCO coated conductor prepared by MOD-TFA method (유기첨가제가 MOD-TFA법으로 제조된 YBCO에 미치는 영향)

  • 김영국;유재무;고재웅;허순영
    • Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
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    • 2003.10a
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    • pp.90-92
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    • 2003
  • Effects of organic additives on YBCO coated conductor prepared by MOD-TFA method were investigated. YBCO thin films were deposited on (100)-oriented single crystalline LaAlO$_3$substrates by conventional MOD-TFA process. The microstructures of YBCO thin films show labyrinth-like patterns. The origin of this microstructure was delineated by compositional inhomogeneity during the pyrolysis process of MOD process and it was shown that organic additives changes the microstructure and texture development of grown YBCO films

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A Performance Evaluation Model for Order Picking System Using AutoMod (AutoMod를 이용한 오더피킹시스템의 능력산정 모델의 연구)

  • 황흥석
    • Proceedings of the Korea Society for Simulation Conference
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    • 1999.04a
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    • pp.42-46
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    • 1999
  • 본 연구는 AutoMod를 이용한 오더피킹시스템의 최적설계 성능산정을 위한 모델의 연구로서 오더피킹 방법은 통로끝오터피킹(End-of-Aisle OP)의 방법을 사용하였다. 오더피피킹방법으로 시스템의 성능 산정을 위한 수리 모델과 이의 전산프로그램을 개발하였다. 수리모델의 제한사항들을 보완하기 위하여 AutoMod를 이용한 시뮬레이션방법을 응용하고 과정을 보였다. 예제를 통해서 구해진 각 시스템의 오더피킹 능력산정에의 응용결과를 구하였고, 주어진 수리모델의 결과와 AutoMod를 이용한 시뮬레이션방법으로 구한 결과를 도출하고 결과를 비교하여 보았다.

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Electromagnetic properties of HTS coated conductors fabricated by PLD and MOD (PLD 및 MOD법으로 제조된 2세대 HTS 선재의 전자기 특성)

  • Oh, Sang-Soo;Hwang, Sun-Yuk;Song, Kyu-Jeong;Kang, Suk-Il;Ha, Dong-Woo;Ko, Rock-Kil;Park, Chan
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2004.11a
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    • pp.65-68
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    • 2004
  • A lot of R&D efforts are being concentrated on the development of high performance HTS coated conductors(CC). Unlike the HTS Bi-2223 tape, a variety of processes have been tried to fabricate CC tapes. PLD and MOD are believed to be very effective methods, and high critical currents of long length CC tape have been reported. In this study, we prepared two kinds of YBCO CCs to evaluate electromagnetic property. One is YBCO tape deposited on IBAD template by PLD and the other is AMSC's MOD CC tape Critical current (Ic) in magnetic fields, its angular dependency, and n-value were measured and analyzed. Magnetic field property of Ic was appeared to be different due the fabrication process. MOD tape showed higher in-field property, n-value of both PLD and MOD tapes exponentially decreased with magnetic field. MOD tape showed higher n-value in whole magnetic fields.

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Design of a Parallel Multiplier for Irreducible Polynomials with All Non-zero Coefficients over GF($p^m$) (GF($p^m$)상에서 모든 항의 계수가 0이 아닌 기약다항식에 대한 병렬 승산기의 설계)

  • Park, Seung-Yong;Hwang, Jong-Hak;Kim, Heung-Soo
    • Journal of the Institute of Electronics Engineers of Korea SC
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    • v.39 no.4
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    • pp.36-42
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    • 2002
  • In this paper, we proposed a multiplicative algorithm for two polynomials with all non-zero coefficients over finite field GF($P^m$). Using the proposed multiplicative algorithm, we constructed the multiplier of modular architecture with parallel in-output. The proposed multiplier is composed of $(m+1)^2$ identical cells, each cell consists of one mod(p) additional gate and one mod(p) multiplicative gate. Proposed multiplier need one mod(p) multiplicative gate delay time and m mod(p) additional gate delay time not clock. Also, our architecture is regular and possesses the property of modularity, therefore well-suited for VLSI implementation.

An Analysis of the Loss of Residual Heat Removal System Event for Pressurized Water Reactor at Reduced Inventory Operation (가압경수로의 저수위 운전시 잔열제거계통 상실사고에 대한 분석)

  • Han, Kee-Soo;Song, Jin-Ho
    • Nuclear Engineering and Technology
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    • v.27 no.5
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    • pp.645-660
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    • 1995
  • The loss of Residual Heat Removal System (RHRS) event during reduced inventory operation for the Korean Standard Nuclear Power Plants (KSNPPS) is simulated by RELAP5/MOD3 and RELAP5/MOD3.1 Tn cases are considered : Base case for an intact Reactor Coolant System (RCS) with no tent and a vent case for an open system. Comparative simulations of base case are peformed by RELAP5/MOD3 and RELAP5/MOD3. 1 computer codes. The results of too simulations are generally in good qualitative and quantitative agreement. However, since the results of RELAP5/MOD3 simulation reveals the deficiency of RELAP5/MOD3 wall heat model, the RELAP5/AOD3.1 computer code is used for the simulation of the vent case. The analysis result of base case show that two steam generators are insufficient to remove decay heat at one day after shutdown, where the RCS is closed. The RCS pressure increased continuously and reached the RCS temporary boundaries design pressure of 0.24 MPa around 4,000 seconds. In the vent case with a flow capacity equivalent to three times the capacity of Pressurizer Safety Valve (PSV), it is shown that the RCS Pressure does not reach 0.24 MPa and core uncovery does not occur until 10,000 seconds. The detailed discussions on the results of this study suggest the feasibility of RELAP5/AOD3.1 as an analysis tool for the simulation of the loss of RHRS event at reduced inventory operation. The results of this study also provide insight for the determination of proper vent capacity.

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Proposan and Analysis of DR(Distributed Reflector)-LD/EA(electro-absorption)­Modulator Integrated Device (분포반사기 레이저 다이오드와 광흡수 변조기가 집적된 소자의 제안 및 해석)

  • 권오기;심종인
    • Korean Journal of Optics and Photonics
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    • v.9 no.5
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    • pp.333-341
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    • 1998
  • The novel integrated device, 1.55 ${\mu}{\textrm}{m}$ DR-LD(distrbuted reflector laser diode) integrated EA-MOD (electro-absorption modulator) as light source, is proposed to improve the device yield and its operational performances. This device can be easily fabricated by the selective MOVPE technique and its fabrication processes are almost the same as the reported 1.55 ${\mu}{\textrm}{m}$ DFB-LD(distributed feedback laser diode) integrated EA-MOD except the asymmetric gratings. The static and dynamic properties are investigated simultaneously by solving the transfer matrix method for light propagation, the time-dependent rate equation for carrier change and schr$\"{o}$dinger equation for QCSE (Quantum-Confined Stark Effect). The performances of the proposed device such as output power, chirp, and extinction ratio are compared with those of DFB-LD integrated EA-MOD. Under 10Gb/s NRZ modulation, we obtain that DR-LD integrated EA-MOD. is 30% higher in output power on the on-state, about 50% lower in chirp, and slightly larger in extinction ratio than DFB-LD integrated EA-MOD.-MOD.

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Effect of Carbides on the Pitting Corrosion of Mod. 440A Martensitic Stainless Steel (Mod. 440A 마르텐사이트계 스텐인리스강의 공식에 미치는 탄화물의 영향)

  • Kwon, Soon-Doo;Heo, Sung-Hwa;Kang, Chang-Yong
    • Korean Journal of Materials Research
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    • v.25 no.12
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    • pp.666-671
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    • 2015
  • In this study, we investigated the effect of the residual carbides and tempered carbides precipitated by tempering treatment after quenching on the pitting corrosion of mod. 440A martensitic stainless steel. In quenched specimens and tempered specimens after quenching of mod. 440A martensitic stainless steel, the volume fraction of the residual carbides and total carbides decreased with the increase of the austenitizing temperature. Pitting resistance increased with the increase of austenitizing temperature. With the increase of the volume fraction of the residual and total carbides, the pitting resistance of mod. 440A martensitic stainless steel was decreased. The pitting resistance of mod. 0.5C-17Cr-0.5Ni 440A martensitic stainless steel had stronger affected by residual carbides than precipitated carbides produced by tempering.

MOD-processed YBCO thin films prepared by chemically controlled precursor solution (화학적으로 제어된 전구체용액을 사용하여 MOD법으로 제조된 YBCO 박막)

  • 유재무;김영국;고재웅;허순영;홍계원;이희균;김철진;정경원
    • Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
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    • 2003.10a
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    • pp.27-29
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    • 2003
  • Solution-based MOD-TFA deposition technology of YBCO layers offers a route to low-cost YBCO coated conductors. Since the structures and properties of grown thin film by MOD process are strongly influenced by chemistry of precursor solution, the chemical modification of precursor solution for MOD process are important for improvement of the electrical properties of YBCO films. In this study, the precursor solution for MOD process are modified by chemical additives and solvents. The microstructure and texture of YBCO films grown by chemically modified precursor solution were characterized with SEM/EDS, XRD.

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