• Title/Summary/Keyword: Lpp

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Experimental Investigation of Composite Insulator for Insulation Design of HTS Cable (고온 초전도 케이블의 절연설계를 위한 복합절연물의 시험 연구)

  • Nguyen, Van Dung;Baek, Seung-Myeong;Cheon, Hyeon-Gweon;Kwag, Dong-Sun;Kim, Sang-Hyun
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2004.11a
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    • pp.331-336
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    • 2004
  • Due to the outstanding insulating characteristics, Laminated Polypropylene paper (LPP) and Kraft paper have been used as ac power insulation for conventional cable. Recently, both of LPP and Kraft has been studied as main insulation fur high temperature superconducting (HTS) cable. Ifowever, studies on the use of LPP/Kraft paper for HTS cables are thinly scattered. In this paper, the comparison among LPP, Kraft and LPP/Kraft Samples impregnated with liquid nitrogen $(LN_2)$ on dielectric insulation characteristics was investigated. It was found from the experimental data that the breakdown strength becomes lower in the order LPP, Lpp/Kraft and Kraft but the lifetime indices n becomes lower in the order Kraft, LPP/Kraft, LPP. Moreover, partial discharge inception and dielectric loss tangent become lower in the order Kraft, LPP, LPP/Kraft.

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Effect of Laminated Polypropylene Paper on the Breakdown Strength of Multi-layer Insulation for HTS Cable

  • Nguyen, Van-Dung;Baek, Seung-Myeong;Kwag, Dong-Soon;Kim, Sang-Huyn
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2004.05b
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    • pp.87-93
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    • 2004
  • Laminated Polypropylene Paper (LPP) and Kraft paper were used as ac power insulation for conventional cable as well as high temperature superconducting (HTS) cable because of its prominent insulating characteristics. However, researches on the use of LPP/Kraft paper in HTS cables are thinly scattered. In this paper, the effect of laminate polypropylene paper on the breakdown strength of LPP/Kraft multi-layer sample impregnated with liquid nitrogen (LN2)under ac and impulse applied voltage was studied. In addition, the breakdown strength characteristics of LPP and Kraft multi-layer sample were also investigated. It was found from the experimental data that the LPP has higher breakdown strength value than Kraft paper in ac and impulse. Especially in the ac case, the breakdown strength increases as the component ratio of LPP in the LPP/Kraftsample increases and slightly affected by the inserting position of LPP but in impulse case, the breakdown strength strongly depends on the number of LPP and the relative position of LPP.

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A Case of Localized Pustular Psoriasis (국소성 농포성 건선 치험 1례)

  • Choi, Joon-Gi;Choi, Eun-Hee;Kim, Kung-Joon;Park, Min-Cheul
    • The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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    • v.19 no.2
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    • pp.313-319
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    • 2006
  • Background and Objective : Localized Pustular Psoriasis(LPP) is a rare form of psoriasis characterized by erythematous papules, plaques studded with pustules(usually on palms or soles) However, the pathophysiology of the LPP remains obscure. Treatment at present is symptomatic and supportive. There is no report on LPP treated with oriental medical treatment. Methods : We conducted one patient with LPP seen at Won-Kwang University Ik-San Oriental Medical Hospital in 2003. We treated LPP in a forty-nine years old man by a herbal medicine, acupuncture, moxa, etc Conclusions : We had a significant results. So we report this case to estimate the efficiency of oriental medic at treatment and management on LPP

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A Study on the Removal of LPP CMP Induced Defect (LPP(Landing Plug Poly) CMP Induced Defect 제거에 관한 연구)

  • Oh, Pyeong-Won;Choi, Jea-Gon;Choi, Yong-Soo;Choi, Geun-Min;Song, Yong-Wook
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2004.07a
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    • pp.235-238
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    • 2004
  • 본 연구는 반도체소자 제조공정에 적용되는 CMP공정 중 LPP(Landing Plug Poly) Contact간의 소자 분리를 위해 진행되는 LPP CMP의 후 세정 과정에서 유발되는 방사형 Defect 제거에 관한 내용이다. 방사형 Defect은 LPP CMP 후에 노출되는 BPSG, Poly, Nitride Film과 연마재로 사용되는SiO2 입자, 후 세정과정에서 적용되는 SC-1, DHF, $NH_4OH$ Chemical과 Brush와의 상호작용에 의해 발생되며, Cleaning시의 산성 분위기 하에서 각 물질간의 pH와 Zeta Potential의 차이에서 기인한다. 이 Defect을 제거하기 위해 LPP CMP후에 Film 표면에 노출되는 각 물질의 표면 특성과 CMP 후 오염입자의 흡착과 재 흡착에 영향을 미치는 Electrostatic force와 Van der Waals force, PVA Brush에 의한 Mechanical force의 상호작용을 고려하여 최적 후 세정 조건을 제시 하였다.

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2D-MELPP: A two dimensional matrix exponential based extension of locality preserving projections for dimensional reduction

  • Xiong, Zixun;Wan, Minghua;Xue, Rui;Yang, Guowei
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.16 no.9
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    • pp.2991-3007
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    • 2022
  • Two dimensional locality preserving projections (2D-LPP) is an improved algorithm of 2D image to solve the small sample size (SSS) problems which locality preserving projections (LPP) meets. It's able to find the low dimension manifold mapping that not only preserves local information but also detects manifold embedded in original data spaces. However, 2D-LPP is simple and elegant. So, inspired by the comparison experiments between two dimensional linear discriminant analysis (2D-LDA) and linear discriminant analysis (LDA) which indicated that matrix based methods don't always perform better even when training samples are limited, we surmise 2D-LPP may meet the same limitation as 2D-LDA and propose a novel matrix exponential method to enhance the performance of 2D-LPP. 2D-MELPP is equivalent to employing distance diffusion mapping to transform original images into a new space, and margins between labels are broadened, which is beneficial for solving classification problems. Nonetheless, the computational time complexity of 2D-MELPP is extremely high. In this paper, we replace some of matrix multiplications with multiple multiplications to save the memory cost and provide an efficient way for solving 2D-MELPP. We test it on public databases: random 3D data set, ORL, AR face database and Polyu Palmprint database and compare it with other 2D methods like 2D-LDA, 2D-LPP and 1D methods like LPP and exponential locality preserving projections (ELPP), finding it outperforms than others in recognition accuracy. We also compare different dimensions of projection vector and record the cost time on the ORL, AR face database and Polyu Palmprint database. The experiment results above proves that our advanced algorithm has a better performance on 3 independent public databases.

A Study on the Electrical and Optical Properties of Micro-Pattern of Polypyrrole(PPy) by Using Vapor Phase Polymerization (기상중합법을 이용한 Polypyrrole(PPy) 필름의 전기적/광학적 특성 및 미세패턴 형성에 관한 연구)

  • Han, Yong-Hyeon;Yim, Jin-Heong
    • Polymer(Korea)
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    • v.34 no.5
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    • pp.450-453
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    • 2010
  • The electrical/optical properties and surface structures of polypyrrole (PPy) thin films, which were prepared by liquid phase polymerization (LPP) and vapor phase polymerization (VPP) of pyrrole using FTS as an initiatior are compared. The PPy thin film prepared by VPP showed superior surface resistance characteristics as compared with that prepared by LPP. We investigated the relation between surface morphology of PPy film and surface resistance by surface characteristic analysis. The surface of PPy thin film prepared by VPP was smoother than that prepared by LPP. Micro-patterned PPy thin film could be prepared effectively using VPP-combined ink-jet printing and soft lithography.

The Development of LPP Combustor for ESPR

  • Kinoshita, Yasuhiro;Oda, Takeo;Kobayashi, Masayoshi;Ninomiya, Hiroyuki;Kimura, Hideo;Hayashi, Shigeru;Yamada, Hideship;Shimodaira, Kazuo
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2004.03a
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    • pp.453-459
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    • 2004
  • An axially staged combustor equipped with an LPP combustion system and CMC liner walls has been investigated for stable combustion and low NOx emissions for the ESPR project. Several fuel injectors were designed and manufactured for the LPP burner, and single sector combustor tests were conducted to evaluate fundamental combustion characteristics such as emissions, instabilities, auto-ignition, and flash back at typical operating conditions from idle to Mn 2.2 cruise. The latest test results showed that the LPP burner had a good potential for the low NOx target. It was also found that the NOx emission level was greatly affected by a distortion in the air flow velocity field upstream of the LPP burner due to the diffuser and fuel feed arm. The CMC material was investigated to apply for the high temperature and low NOx combustor. Annular combustor liner walls were manufactured with the CMC material, and they have been tested at low pressure conditions to evaluate the soundness of the material and the mounting and seal system. This paper reports the latest research activities on the LPP combustion system and CMC liner walls for the ESPR project.

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LOCAL PERMUTATION POLYNOMIALS OVER FINITE FIELDS

  • Lee, Jung-Bok;Ko, Hyoung-June
    • Communications of the Korean Mathematical Society
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    • v.9 no.3
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    • pp.539-545
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    • 1994
  • Let $q = p^r$, where p is a prime. A polynomial $f(x) \in GF(q)[x]$ is called a permutation polynomial (PP) over GF(q) if the numbers f(a) where $a \in GF(Q)$ are a permutation of the a's. In other words, the equation f(x) = a has a unique solution in GF(q) for each $a \in GF(q)$. More generally, $f(x_1, \cdots, x_n)$ is a PP in n variables if $f(x_1,\cdots,x_n) = \alpha$ has exactly $q^{n-1}$ solutions in $GF(q)^n$ for each $\alpha \in GF(q)$. Mullen ([3], [4], [5]) has studied the concepts of local permutation polynomials (LPP's) over finite fields. A polynomial $f(x_i, x_2, \cdots, x_n) \in GF(q)[x_i, \codts,x_n]$ is called a LPP if for each i = 1,\cdots, n, f(a_i,\cdots,x_n]$ is a PP in $x_i$ for all $a_j \in GF(q), j \neq 1$.Mullen ([3],[4]) found a set of necessary and three variables over GF(q) in order that f be a LPP. As examples, there are 12 LPP's over GF(3) in two indeterminates ; $f(x_1, x_2) = a_{10}x_1 + a_{10}x_2 + a_{00}$ where $a_{10} = 1$ or 2, $a_{01} = 1$ or x, $a_{00} = 0,1$, or 2. There are 24 LPP's over GF(3) of three indeterminates ; $F(x_1, x_2, x_3) = ax_1 + bx_2 +cx_3 +d$ where a,b and c = 1 or 2, d = 0,1, or 2.

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Comparison of the Organophosphorus Hydrolase Surface Display Using InaVN and Lpp-OmpA Systems in Escherichia coli

  • Karami, Ali;Latifi, Ali Mohamad;Khodi, Samaneh
    • Journal of Microbiology and Biotechnology
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    • v.24 no.3
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    • pp.379-385
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    • 2014
  • The purpose of this study was to compare the ability of an engineered Escherichia coli to degrade chlorpyrifos (Cp) using an organophosphorus hydrolase enzyme, encoded in both Flavobacterium sp. ATCC 27551 or Pseudomonas diminuta, by employing the Lpp-OmpA chimera and the N-terminal domain of the ice nucleation protein as anchoring motifs. Tracing of the expression location of the recombinant protein using SDS-PAGE showed the presentation of OPH by both anchors on the outer membrane. This is the first report on the presentation of OPH on the cell surface by Lpp-OmpA under the control of the T7 promoter. The results showed cell growth in the presence of Cp as the sole source of energy, without growth inhibition, and with higher whole-cell activity for both cells harboring plasmids pENVO and pELMO, at approximately 10,342.85 and 10,857.14 U/mg, respectively. Noticeably, the protein displayed by pELMO was lower than the protein displayed by pENVO. It can be concluded that Lpp-OmpA can display less protein, but more functional OPH protein. These results highlight the high potential, of both engineered bacteria, for use in the bioremediation of pesticide-contaminated sources in the environment.

Local Path Planning Manager for Autonomous Navigation of UGV (무인차량의 자율주행을 위한 지역경로계획 매니저)

  • Lee, Young-Il;Lee, Ho-Joo;Park, Yong-Woon
    • Journal of the Korea Institute of Military Science and Technology
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    • v.13 no.6
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    • pp.990-997
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    • 2010
  • The Mission environment of UGV(Unmanned Ground Vehicle) has a complexity and variety, and the status of system and sensor is dependent on the environment factors such as operation time, the weather and road type. It is necessary for UGV to cope adaptively with the various mission types, operation modes and operation environment as human operators do. To satisfy this necessity, we present an autonomy manager based on the autonomous architecture. In this paper, we design a path planning software architecture and LPP manager by using open autonomous architecture which is previously designed by ADD. Field test is conducted with UGV in order to verify the performance of LPP Manager based on the Autonomous Architecture with scenarios.