• 제목/요약/키워드: $P_n$

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p-GaN/AlGaN/GaN E-mode FET 제작을 위한 선택적 GaN 식각 공정 개발 (Development of Selective GaN etching Process for p-GaN/AlGaN/GaN E-mode FET Fabrication)

  • Jang, Won-Ho;Cha, Ho-Young
    • 한국정보통신학회논문지
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    • 제24권2호
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    • pp.321-324
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    • 2020
  • In this work, we developed a selective etching process for GaN that is a key process in p-GaN/AlGaN/GaN enhancement-mode (E-mode) power switching field-effect transistor (FET) fabrication. In order to achieve a high current density of p-GaN/AlGaN/GaN E-mode FET, the p-GaN layer beside the gate region must be selectively etched whereas the underneath AlGaN layer should be maintained. A selective etching process was implemented by oxidizing the surface of the AlGaN layer and the GaN layer by adding O2 gas to Cl2/N2 gas which is generally used for GaN etching. A selective etching process was optimized using Cl2/N2/O2 gas mixture and a high selectivity of 53:1 (= GaN/AlGaN) was achieved.

n-6/n-3 지방산 비율이 고지혈증 랫드의 지질대사 분할에 미치는 영향 (Effect of n-6/n-3 fatty acid ratio on metabolic partitioning in hyperlipidemic rats)

  • 이승형;엄경환;박병성
    • 한국응용과학기술학회지
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    • 제35권3호
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    • pp.643-653
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    • 2018
  • 본 연구는 고지혈증 모델동물 랫드에서 n-6/n-3가 서로 다른 식이를 급여하였을 때 혈액지질의 대사적 분할에 미치는 작용 메카니즘을 생체 모니터링 기법으로 구명하였다. 총 glycerolipids의 간에서 대사된 cholesteryl $^{14}C$-oleate 비율은 n-6/n-3 비율 4:1, 15:1, 30:1, 대조군 순서로 낮았다(p<0.05). 인지질 분비량은 대조군과 비교할 때 n-6/n-3 비율 4:1, 15:1, 30:1 순서로 높았다(p<0.05). 중성지방 분비량은 대조군과 비교할 때 n-6/n-3 비율 4:1, 15:1, 30:1 순서로 특히, 4:1 처리군에서 낮았다(p<0.05). 총 glycerolipid에 대한 인지질의 분할 비율은 n-6/n-3 비율 4:1, 15:1, 30:1, 대조군 순서로 높았다(p<0.05). 간으로부터 중성지방 분할 비율(%)은 대조군 82.25%와 비교할 때 n-6/n-3 비율 4:1, 15:1, 30:1에서 각각 72.99, 75.93, 78.12%로써 n-6/n-3 비율이 증가할수록 높아졌다(p<0.05). 인지질 분할 비율(%)은 대조군 11.04%와 비교할 때 n-6/n-3 비율 4:1, 15:1, 30:1에서 각 25.15, 18.87, 18.15%로써 n-6/n-3 비율이 증가할수록 낮아졌다(p<0.05).

NADH 센서를 이용한 생물학적 동시 탈질.질산화공정에서 질소, 인제거 영향인자 및 거동 평가 (Evaluation of Affecting Factors on N and P removal in Biological SND (Simultaneous Nitrification and Denitrification) Process with NADH Sensor)

  • 김한래;이시진
    • 한국환경보건학회지
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    • 제34권5호
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    • pp.374-381
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    • 2008
  • In this study, the factors affecting biological N and P removal using SND (simultaneous nitrification and denitrification) process were investigated and evaluated to examine the possibility of treating N and P through SND with NADH by surveying N and P traces in an aeration tank. Variations of $NH_4^+$-N+$NO_3^-$-N concentration were used to estimate the degree of SND in each point (P2, P3, P4, P5) of the aeration tank and these variations showed that denitrification efficiency in P2 (front zone), nitrification and denitrification efficiencies in P4 (middle zone) were 67%, 86% and 39%, respectively. When $PO_4^{-3}$-P concentration was analyzed in each point of the aeration tank, it was shown that $PO_4^{-3}$-P concentration coming into P2 was 1.25 mg/L, which increased to 2.22 mg/L by P release in P2 zone and then decreased to 0.74 mg/L by P uptake in P4. Consequently, we were able to estimate which high P removal efficiency observed in this study was caused by biological phosphorus removal. To determine the operating factors affecting effluent T-N, we analyzed the correlation among FN/M ratio, C/N ratio, Temp., SRT etc and these results showed that the correlation among FN/M ratio, C/N ratio and Temp was not high. However, the relationship of SRT and other parameters (effluent $NH_4^+$-N and effluent BOD) and the short SRT could have an affect on effluent $NH_4^+$-N and so effluent BOD could be increased. Thus, SRT operation should be controlled over 10 days. The results for analyzing the correlation between SRT and influent $NO_3^-$-N in order to investigate the operating factors affecting effluent T-P showed that T-P or $PO_4^{-3}$-P was not highly correlation with SRT, whereas $PO_4^{-3}$-P concentration increased along with increasing $NO_3^-$-N concentration into P2. Based on these results, we concluded, using regression analysis (R2=0.97), that effluent $PO_4^{-3}$-P concentration depends on $NO_3^-$-N concentration into P2.

p-n Heterojunction Composed of n-ZnO/p-Zn-doped InP

  • Shim, Eun-Sub;Kang, Hong-Seong;Kang, Jeong-Seok;Pang, Seong-Sik;Lee, Sang-Yeol
    • Transactions on Electrical and Electronic Materials
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    • 제3권1호
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    • pp.1-3
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    • 2002
  • A p-n junction was obtained by the deposition of an n-type ZnO thin film on a p-type Zn-doped InP substrate. The Zn-doped InP substrate has been made by the diffusion of Zn with sealed ampoule technique. The ZnO deposition process was performed by pulsed laser deposition (PLD). The p-n junction was formed and showed typical I-V characteristics. We will also discuss about the realization of an ultraviolet light-emitting diode (LED). The structure of n-ZnO/p-Zn-doped InP could be a good candidate for the realization of an ultraviolet light-emitting diode or an ultraviolet laser diode.

Vinylsulfilimine유도체에 대한 1-methyl-5-mercapto-1,2,3,4-tetrazole의 친핵성 첨가물에 관한 연구 (Synthetic Studies on the Nucleophilic Addition of 1-Methyl-5-mercapto-1,2,3,4-tetrazole to Vinylsulfilimines)

  • 김태린;이소영;변상용
    • 대한화학회지
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    • 제36권2호
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    • pp.318-323
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    • 1992
  • Vinylsulfilimine 유도체(H, p-$CH_3$, m-TEX>$CH_3$, p-Cl, p-Br, p-$OCH_3$, 및 p-$NO_2$)에 1-methyl-5-mercapto-1,2,3,4-tetrazole을 반응시켜 다음 7가지의 새로운 호합물을 합성하였다. S-Phenyl-S-2-(1-methyl-1,2,3,4-tetrazole-5-thio)-ethyl-N-p-tosylsulfilimine, S-p-tolyl-S-2-(1-methyl-1,2,3,4-tetrazole-5-thio)-ethyl-N-p-tosylsulfilimine, S-m-tolyl-S-2-(1-methyl-1,2,3,4-tetrazole-5-thio)-ethyl-N-p-tosylsulfilimine, S-p-chlorophenyl-S-2-(1-methyl-1,2,3,4-tetrazole-5-thio)-ethyl-N-p-tosylsulfilimine, S-p-bromophenyl-S-2-(1-methyl-1,2,3,4-tetrazole-5-thio)-ethyl-N-p-tosylsulfilimine, S-p-methoxyphenyl-S-2-(1-methyl-1,2,3,4-tetrazole-5-thio)-ethyl-N-p-tosylsulfilimine and S-p-nitrophenyl-S-2-(1-methyl-1,2,3,4-tetrazole-5-thio)-ethyl-N-p-tosylsulfilimine. 이 화합물들의 구조는 원소분석, MP, UV, IR 및 NMR 스펙트럼에 의해 확인되었다.

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THE COMPUTATION METHOD OF THE MILNOR NUMBER OF HYPERSURFACE SINGULARITIES DEFINED BY AN IRREDUCIBLE WEIERSTRASS POLYNOMIAL $z^n$+a(x,y)z+b(x,y)=0 in $C^3$ AND ITS APPLICATION

  • Kang, Chung-Hyuk
    • 대한수학회보
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    • 제26권2호
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    • pp.169-173
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    • 1989
  • Let V={(x,y,z):f=z$^{n}$ -npz+(n-1)q=0 for n .geq. 3} be a compled analytic subvariety of a polydisc in $C^{3}$ where p=p(x,y) and q=q(x,y) are holomorphic near (x,y)=(0,0) and f is an irreducible Weierstrass polynomial in z of multiplicity n. Suppose that V has an isolated singular point at the origin. Recall that the z-discriminant of f is D(f)=c(p$^{n}$ -q$^{n-1}$) for some number c. Suppose that D(f) is square-free. then we prove that by Theorem 2.1 .mu.(p$^{n}$ -q$^{n-1}$)=.mu.(f)-(n-1)+n(n-2)I(p,q)+1 where .mu.(f), .mu. p$^{n}$ -q$^{n-1}$are the corresponding Milnor numbers of f, p$^{n}$ -q$^{n-1}$, respectively and I(p,q) is the intersection number of p and q at the origin. By one of applications suppose that W$_{t}$ ={(x,y,z):g$_{t}$ =z$^{n}$ -np$_{t}$ $^{n-1}$z+(n-1)q$_{t}$ $^{n-1}$=0} is a smooth family of complex analytic varieties near t=0 each of which has an isolated singularity at the origin, satisfying that the z-discriminant of g$_{t}$ , that is, D(g$_{t}$ ) is square-free. If .mu.(g$_{t}$ ) are constant near t=0, then we prove that the family of plane curves, D(g$_{t}$ ) are equisingular and also D(f$_{t}$ ) are equisingular near t=0 where f$_{t}$ =z$^{n}$ -np$_{t}$ z+(n-1)q$_{t}$ =0.}$ =0.

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포장대맥(圃場大麥)의 생육시기별(生育時期別) 양분농도(養分濃度)와 수량(收量)과의 관계(關係) (Relation between yield and nutrient contents at various growth stages of hulled barley in fields)

  • 박훈
    • 한국토양비료학회지
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    • 제9권1호
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    • pp.39-45
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    • 1976
  • 농가포장(農家圃場)에 실시(實施)한 대맥(大麥) 삼요소(三要素) 시험(試驗)(1967/68)지(地)를 대상(對象)으로 생육시기별(生育時期別) N.P.K.Ca.Mg 농도(濃度), NPK와 수량(收量)과의 상관(相關) 및 NPK 이용율(利用率)을 조사(調査)하여 다음과 같은 결과(結果)를 얻었다. 1. 생육시기별(生育時期別) 농도(濃度)의 변화량(變化量)으로 보아 N와 K가 유이(類似)하고 P, Mg, Ca가 유이(類似)하였다. 2. 수량(收量)은 해빙직후(解氷直後) N농도(濃度)와 가장 유의성(有意性)이 깊고 북부(北部) 즉(卽) 강원(江原)과 충남(忠南)에서는 동결직전(凍結直前)의 P및 N농도(濃度)와 고도(高度)의 유의성(有意性)을 보였다. 기타(其他)의 시기(時期)는 P, K에서 부(負)의 관련경향(關聯傾向)을 보였는데 K에서 더욱 그러했다. 3. 시비량(施肥量)이 증가(增加)할수록 N.P.K 농도(濃度)가 증가(增加)하는 경향(傾向)은 초기(初期)일수록 뚜렷하고 N에서 더욱 뚜렷하며 P와 K가 생육후기(生育後期)에 상대적(相對的)으로 많은 반면 N가 적은 것을 잘 보였으며 N와 K간(間)의 길항관계(拮抗關係)도 잘 보였다. 4. 이용율(利用率)은 N(55)>K(27)>P(12)의 순(順)이었으며 N이용율(利用率)은 수량(收量)이 증가(增加)할수록 증가(增加)하는 경향(傾向)이다. 5. 수량(收量)과 관련(關聯)된 영양진단(營養診斷)은 해빙직후(解氷直後) 또는 직전(直前)이 가장 좋을 것으로 나타났고 생육시기별(生育時期別) 영양(營養) 기준(基準)을 제시(提示)하였다.

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Complete Moment Convergence of Moving Average Processes Generated by Negatively Associated Sequences

  • Ko, Mi-Hwa
    • Communications for Statistical Applications and Methods
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    • 제17권4호
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    • pp.507-513
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    • 2010
  • Let {$X_i,-{\infty}$ < 1 < $\infty$} be a doubly infinite sequence of identically distributed and negatively associated random variables with mean zero and finite variance and {$a_i,\;-{\infty}$ < i < ${\infty}$} be an absolutely summable sequence of real numbers. Define a moving average process as $Y_n={\sum}_{i=-\infty}^{\infty}a_{i+n}X_i$, n $\geq$ 1 and $S_n=Y_1+{\cdots}+Y_n$. In this paper we prove that E|$X_1$|$^rh$($|X_1|^p$) < $\infty$ implies ${\sum}_{n=1}^{\infty}n^{r/p-2-q/p}h(n)E{max_{1{\leq}k{\leq}n}|S_k|-{\epsilon}n^{1/p}}{_+^q}<{\infty}$ and ${\sum}_{n=1}^{\infty}n^{r/p-2}h(n)E{sup_{k{\leq}n}|k^{-1/p}S_k|-{\epsilon}}{_+^q}<{\infty}$ for all ${\epsilon}$ > 0 and all q > 0, where h(x) > 0 (x > 0) is a slowly varying function, 1 ${\leq}$ p < 2 and r > 1 + p/2.

TOPOLOGIES AND INCIDENCE STRUCTURE ON Rn-GEOMETRIES

  • Im, Jang-Hwan
    • 대한수학회지
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    • 제39권1호
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    • pp.31-49
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    • 2002
  • An R$^{n}$ -geometry (P$^{n}$ , L) is a generalization of the Euclidean geometry on R$^{n}$ (see Def. 1.1). We can consider some topologies (see Def. 2.2) on the line set L such that the join operation V : P$^{n}$ $\times$ P$^{n}$ \ $\Delta$ longrightarrow L is continuous. It is a notable fact that in the case n = 2 the introduced topologies on L are same and the join operation V : P$^2$ $\times$ P$^2$ \ $\Delta$ longrightarrow L is continuous and open [10, 11]. It is a fundamental topological property of plane geometry, but in the cases n $\geq$ 3, it is no longer true. There are counter examples [2]. Hence, it is a fundamental problem to find suitable topologies on the line set L in an R$^{n}$ -geometry (P$^{n}$ , L) such that these topologies are compatible with the incidence structure of (P$^{n}$ , L). Therefore, we need to study the topologies of the line set L in an R$^{n}$ -geometry (P$^{n}$ , L). In this paper, the relations of such topologies on the line set L are studied.