• Weed & Turfgrass Science
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• 제2권4호
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• pp.387-394
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• 2013

Rhizoctonia spp. 에 의한 Rhizoctonia 마름병은 잔디에서 중요한 병이며, 골프장에서 잔디의 좋은 품질을 유지하기 위하여 살균제를 사용하고 있다. 본시험은 포장에서 분리한 R. solani AG-1 IB, R. cerealis 및 R. solani AG2-2에 대한 침투성 살균제인 flutolanil, pyraclostrobine, and hexaconazole에 대하여 실내에서 상대적인 균사생장을 효과적으로 50%억제하는 $EC_{50}$농도를 결정하는 시험을 수행하였다. 각각 살균제에 대한 감수성은 3종의 Rhizoctonia균주에 대하여 5 수준의 농도를 사용하였다. 3종류의 살균제에 대한 $EC_{50}$ 값은 R. solani AG-1 IB에서 가장 낮았다. 하지만, R. solani AG2-2에 대한 살균제 감수성은 pyraclostrobine 과 flutolanil에서 평균 $EC_{50}$ 값이 0.026 ${\mu}g\;a.i.\;ml^{-1}$ 와 0.044 ${\mu}g\;a.i.\;ml^{-1}$ 로 가장 높았다. R. cerealis은 hexaconazole에서 $EC_{50}$ 값이 0.022 ${\mu}g\;a.i.\;ml^{-1}$로 가장 감수성이 낮았다. 각각의 살균제의 $EC_{50}$값을 사용하여 두 농약을 혼용한 3종의 조합에서 3종의 병원균에 대한 균사 생장억제율은 R. solani AG2-2에서 가장 높았다. 본 연구결과는 포장에서 Rhizoctonia 마름병을 방제하기 위하여 실내에서 침투성 살균제에 대한 반응을 확인할 수 있었다.

• 대한의생명과학회지
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• 제13권1호
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• pp.39-45
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• 2007

Numerous psychological stressors playa role in development of the cardiovascular disease. The aim of this study was to determine whether a combined mental activity with experimental subway noise affects hematological physiology. Fifty-four healthy volunteers were divided group I which underwent subway noise (n=24) and group II which underwent a combined mental activity with subway noise (n=30). Venous blood samples were collected for measuring CBC, prothrombine time (PT), activated partial thromboplastine time (APTT), erythrocyte sedimentation rate (ESR), D-dimer and high sensitive C-reactive protein (H-CRP) levels before, 50 min of stress task (S-50m) and 60 min of recovery (R-60m). Changed ratios of granulocyte, lymphocyte, monocyte and platelet counts at S-50m and R-60m were higher in group II compared to group I. RBC count and hematocrit level in group I increased whereas those in group II decreased at S-50m. PT, APTT and ESR in the both groups were shortened at R-60m and the decreased ratios were high in group II compared to group I. H-CRP and D-dimer in the both groups were elevated at S-50m and R-60m while the increased ratios in group II were greater than those in group I. These observations imply that a combined mental activity with experimental subway noise may be a stressor which affects hematological physiology.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2005년도 하계학술대회 논문집 Vol.6
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• pp.105-106
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• 2005

The impact ionization MOS (I-MOS) transistor with 50nm channel length is presented by using 2-D device simulator ISE-TCAD. The subthreshold slope cannot be steeper than kT/q since the subthreshold conduction is due to diffusion current. As MOSFETs are scaled down, this problem becomes significant and the subthreshold slope degrades which leads an increase in the off-current and off-state power dissipation. The I-MOS is based on a gated p-i-n structure and the subthreshold conduction is induced by impact ionization. The simulation results show that the subthreshold slope is 11.7 mV/dec and this indicates the I-MOS improves the switching speed and off-state characteristics.

• The Korean Journal of Physiology and Pharmacology
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• 제20권1호
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• pp.119-127
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• 2016

Dihydropyridine (DHP) calcium channel blockers (CCBs) have been widely used to treat of several cardiovascular diseases. An excessive shortening of action potential duration (APD) due to the reduction of $Ca^{2+}$ channel current ($I_{Ca}$) might increase the risk of arrhythmia. In this study we investigated the electrophysiological effects of nicardipine (NIC), isradipine (ISR), and amlodipine (AML) on the cardiac APD in rabbit Purkinje fibers, voltage-gated $K^+$ channel currents ($I_{Kr}$, $I_{Ks}$) and voltage-gated $Na^+$ channel current ($I_{Na}$). The concentration-dependent inhibition of $Ca^{2+}$ channel currents ($I_{Ca}$) was examined in rat cardiomyocytes; these CCBs have similar potency on $I_{Ca}$ channel blocking with $IC_{50}$ (the half-maximum inhibiting concentration) values of 0.142, 0.229, and 0.227 nM on NIC, ISR, and AML, respectively. However, ISR shortened both $APD_{50}$ and $APD_{90}$ already at $1{\mu}M$ whereas NIC and AML shortened $APD_{50}$ but not $APD_{90}$ up to $30{\mu}M$. According to ion channel studies, NIC and AML concentration-dependently inhibited $I_{Kr}$ and $I_{Ks}$ while ISR had only partial inhibitory effects (<50% at $30{\mu}M$). Inhibition of $I_{Na}$ was similarly observed in the three CCBs. Since the $I_{Kr}$ and $I_{Ks}$ mainly contribute to cardiac repolarization, their inhibition by NIC and AML could compensate for the AP shortening effects due to the block of $I_{Ca}$.

• 한국초전도학회:학술대회논문집
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• 한국초전도학회 2008년도 High Temperature Superconductivity Vol.XVIII
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• pp.50-50
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• 2008

• Bulletin of the Korean Chemical Society
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• 제30권8호
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• pp.1729-1732
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• 2009

Bioactivity-guided fractionation led to the isolation of two new phenylpropanoids, 3-O-p-coumaroyl-1-(4-hydroxy- 3,5-dimethoxyphenyl)-1-propanone (1) and 3-O-p-coumaroyl-1-(4-hydroxy-3,5-dimethoxyphenyl)-1-O-$\beta$-gulcopyranosylpropanol (2), together with three known compounds, N-p-coumaroylserotonin (3), N-feruloylserotonin (4) and p-coumaric acid (5) from the leaves of Sasa quelpaertensis Nakai. Their structures were elucidated by spectroscopic methods including 1D and 2D-NMR. Compared to arbutin (I$C_{50}$ 0.048 mM) as a control, compounds 3 and 4 exhibited stronger tyrosinase inhibition activities with an I$C_{50}$ values of 0.027 mM and 0.026 mM, respectively. Compounds 1 (I$C_{50}$ 0.055 mM) and 2 (I$C_{50}$ 0.053 mM) also showed strong activities.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2008년도 춘계학술대회 논문집
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• pp.451-465
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• 2008

지하철에서는 직류보호계전시스템으로 정한시과전류계전기(76i)와 저전압계전기(Mid-point Relay, 80A)를 사용하여 직류급전계통을 보호하고 있었으나, 최근에는 보호방식으로 고장선택계전기(50F)를 주로 적용하고 있다. 본 연구에서는 현재 서울메트로 3 4호선에 적용하여 사용하고 있는 76i/80A와 50F 각각의 직류급전계통 보호방식을 비교하기 위해 단락고장계산식을 이용하여 분석하였으며 PSCAD/EMTDC 과도프로그램을 통한 시뮬레이션으로 연구하였다. 분석한 결과 80A는 고장저항의 크기에 따라 동작여부가 달라지고, 50F의 경우 고장저항의 크기나 선로의 길이가 변하더라도 일정시간이 지나면 설정값에 따라 동작함을 확인하였다. 이에 향후 직류보호계전시스템의 운영에 있어 합리적인 적용을 제시하고자 한다.

• Korean Journal of Mathematics
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• 제16권3호
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• pp.323-334
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• 2008

We define injective and projective representations of quivers with two vertices with n arrows. In the representation of quivers we denote n edges between two vertices as ${\Rightarrow}$ and n maps as $f_1{\sim}f_n$, and $E{\oplus}E{\oplus}{\cdots}{\oplus}E$ (n times) as ${\oplus}_nE$. We show that if E is an injective left R-module, then $${\oplus}_nE{\Longrightarrow[50]^{p_1{\sim}p_n}}E$$ is an injective representation of $Q={\bullet}{\Rightarrow}{\bullet}$ where $p_i(a_1,a_2,{\cdots},a_n)=a_i,\;i{\in}\{1,2,{\cdots},n\}$. Dually we show that if $M_1{\Longrightarrow[50]^{f_1{\sim}f_n}}M_2$ is an injective representation of a quiver $Q={\bullet}{\Rightarrow}{\bullet}$ then $M_1$ and $M_2$ are injective left R-modules. We also show that if P is a projective left R-module, then $$P\Longrightarrow[50]^{i_1{\sim}i_n}{\oplus}_nP$$ is a projective representation of $Q={\bullet}{\Rightarrow}{\bullet}$ where $i_k$ is the kth injection. And if $M_1\Longrightarrow[50]^{f_1{\sim}f_n}M_2$ is an projective representation of a quiver $Q={\bullet}{\Rightarrow}{\bullet}$ then $M_1$ and $M_2$ are projective left R-modules.

• 대한화학회지
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• 제50권1호
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• pp.89-93
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• 2006

• 대한수학회보
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• 제50권2호
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• pp.649-657
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• 2013

Let R be a commutative Noetherian ring, I an ideal of R and T be a non-zero I-cofinite R-module with dim(T) ${\leq}$ 1. In this paper, for any finitely generated R-module N with support in V(I), we show that the R-modules $Ext^i_R$(T,N) are finitely generated for all integers $i{\geq}0$. This immediately implies that if I has dimension one (i.e., dim R/I = 1), then $Ext^i_R$($H^j_I$(M), N) is finitely generated for all integers $i$, $j{\geq}0$, and all finitely generated R-modules M and N, with Supp(N) ${\subseteq}$ V(I).