• Bulletin of the Korean Chemical Society
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• 제27권9호
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• pp.1289-1292
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• 2006

Potassium(I) with 5,7-dihydroxy-6,4'-dimethoxyisoflavone-3'-sulfonate (L) assembles to K($H_2O$)L (L = 5,7-dihydroxy-6,4'-dimethoxyisoflavone-3'-sulfonate). It was characterized by single-crystal X-ray diffraction, element analysis, IR and $^1H$ NMR spectroscopy. It crystallizes in the monoclinic space group $P2_1$/n and reveals a seven-coordinate complex. Polyhedra potassium chains, C-H${\cdot}{\cdot}{\cdot}\pi$ and C-H${\cdot}{\cdot}{\cdot}$O and O-H${\cdot}{\cdot}{\cdot}$O hydrogen bonds lead K($H_2O$)L to a three-dimensional network structure. The biological activity of resistance to hypoxia was tested, and the results showed that the biological activity of resistance to hypoxia of K($H_2O$)L is as good as that of its precursor, irisolidone.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1993년도 하계학술대회 논문집 B
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• pp.1292-1294
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• 1993

This paper proposes a new structure of polycrystalline silicon(poly-Si) thin film transistor(TFT) having a thick gate-oxide below the gate edge. The new structure is fabricated by the gate re-oxidation in wet ambient. It is shown that the thick gate-oxide below the gate edge is effective in reducing the leakage current and the gate-drain overlap capacitance. We have simulated this device by using the SSUPREM4 process simulator and the SPISCES-2B device simulator. As a simulation result it is found that the new structure provides a low tentage current less than 0.2 pA and achieves a on/off ratio as high as $5{\times}10^7$.

• 한국지반환경공학회 논문집
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• 제20권9호
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• pp.13-19
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• 2019

Dynamic earth pressure is considered an important parameter in the design of embedded structures. In current engineering design simplified methods developed either for yielding or non-yielding structures are utilized to predict resultant dynamic pressure. The applicability of these equations to embedded structures have not yet been reported. In this study we perform a suite of equivalent linear time history analysis for a range of embedded structure configurations. Numerically calculated dynamic pressure is shown to depend on the flexibility ratio (F), aspect ratio (L/H) of the embedded structure, and ground motion. Increase in L/H and intensity increases the magnitude of dynamic pressure. An increase in F decreases the dynamic pressure. Overall, the trends highlight the need for development of new method that accounts for F and L/H to calculate the dynamic pressure for the performance-based design of embedded structures.

• 영어어문교육
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• 제10권3호
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• pp.21-40
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• 2004

This study Questioned what happens in L2 reading comprehension of the expository text, as measured by recall and inference-making abilities, when a L2 reader was induced to develop a content schema about the topic of a target text, but the structure of that schema departs from the structure of the target text Seventy-four. Korean university students read either the same version text twice (consistent condition) or two different version texts (inconsistent condition) with a three-day interval between the two readings. The results of a verification test indicate that, for those subjects with higher L2 reading proficiency, the inconsistent condition was more beneficial than the consistent condition for the inference-making task. On the other hand, for lower-level L2 readers, the consistent condition was more favorable for the recall task. It was concluded that inducing a structurally inconsistent schema through an L2 pre-reading would be beneficial only when the reader's L2 linguistic ability is proficient enough to produce necessary propositions from the pre-reading.

• 전기학회논문지
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• 제66권12호
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• pp.1772-1781
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• 2017

In this study, the design methodology for alleviating the overfitting problem of Polynomial Neural Networks(PNN) is realized with the aid of two kinds techniques such as L2 regularization and Sum of Squared Coefficients (SSC). The PNN is widely used as a kind of mathematical modeling methods such as the identification of linear system by input/output data and the regression analysis modeling method for prediction problem. PNN is an algorithm that obtains preferred network structure by generating consecutive layers as well as nodes by using a multivariate polynomial subexpression. It has much fewer nodes and more flexible adaptability than existing neural network algorithms. However, such algorithms lead to overfitting problems due to noise sensitivity as well as excessive trainning while generation of successive network layers. To alleviate such overfitting problem and also effectively design its ensuing deep network structure, two techniques are introduced. That is we use the two techniques of both SSC(Sum of Squared Coefficients) and $L_2$ regularization for consecutive generation of each layer's nodes as well as each layer in order to construct the deep PNN structure. The technique of $L_2$ regularization is used for the minimum coefficient estimation by adding penalty term to cost function. $L_2$ regularization is a kind of representative methods of reducing the influence of noise by flattening the solution space and also lessening coefficient size. The technique for the SSC is implemented for the minimization of Sum of Squared Coefficients of polynomial instead of using the square of errors. In the sequel, the overfitting problem of the deep PNN structure is stabilized by the proposed method. This study leads to the possibility of deep network structure design as well as big data processing and also the superiority of the network performance through experiments is shown.

• Bulletin of the Korean Chemical Society
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• 제35권11호
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• pp.3267-3274
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• 2014

In order to investigate the effects of the double replacement of $\small{L}$-Pro, $\small{D}$-Pro, $\small{D}$-Leu or Nleu (the peptoid residue for Leu) in the hydrophobic face (positions 9 and 13) of amphipathic ${\alpha}$-helical non-cell-selective antimicrobial peptide $L_8K_9W_1$ on the structure, cell selectivity and mechanism of action, we synthesized a series of $L_8K_9W_1$ analogs with double replacement of $\small{L}$-Pro, $\small{D}$-Pro, $\small{D}$-Leu or Nleu in the hydrophobic face of $L_8K_9W_1$. In this study, we have confirmed that the double replacement of $\small{L}$-Pro, $\small{D}$-Pro, or Nleu in the hydrophobic face of $L_8K_9W_1$ let to a great increase in the selectivity toward bacterial cells and a complete destruction of ${\alpha}$-helical structure. Interestingly, $L_8K_9W_1$-$\small{L}$-Pro, $L_8K_9W_1$-$\small{D}$-Pro and $L_8K_9W_1$-Nleu preferentially interacted with negatively charged phospholipids, but unlike $L_8K_9W_1$ and $L_8K_9W_1$-$\small{D}$-Leu, they did not disrupt the integrity of lipid bilayers and depolarize the bacterial cytoplasmic membrane. These results suggested that the mode of action of $L_8K_9W_1$-$\small{L}$-Pro, $L_8K_9W_1$-$\small{D}$-Pro and $L_8K_9W_1$-Nleu involves the intracellular target other than the bacterial membrane. In particular, $L_8K_9W_1$-$\small{L}$-Pro, $L_8K_9W_1$-$\small{D}$-Pro and $L_8K_9W_1$-Nleu had powerful antimicrobial activity (MIC range, 1 to $4{\mu}M$) against methicillin-resistant Staphylococcus aureus (MRSA) and multidrug-resistant Pseudomonas aeruginosa (MDRPA). Taken together, our results suggested that $L_8K_9W_1$-$\small{L}$-Pro, $L_8K_9W_1$-$\small{D}$-Pro and $L_8K_9W_1$-Nleu with great cell selectivity may be promising candidates for novel therapeutic agents, complementing conventional antibiotic therapies to combat pathogenic microorganisms.

• Bulletin of the Korean Chemical Society
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• 제31권7호
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• pp.2031-2035
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• 2010

A triple-probe channel type chemosensor based on an $NO_2S_2$-macrocycle functionalized with phenyltricyanovinyl group was synthesized and its sensing characteristics were examined. The pink-red solution of L changed selectively to pale yellow upon addition of $Hg^{2+}$. The selective fluorometric response of L to all the tested metal ions was studied. The results showed that a large enhancement of the fluorescence of L was observed only in the case of $Hg^{2+}$. In addition, L showed large anodic shift (~ 0.3 V) for the addition of excess $Hg^{2+}$. Through above three observed results by the different techniques, we confirmed that the proposed chemosensor acts as the multiple-probe channel sensing material. The crystal structure of mercury(II) nitrate complexs of L which shows a 1-D polymer network with a formula $[Hg_2(L)_2(NO_3)_2({\mu}-NO_3)_2]_n$ was also reported.

• 대한수학회보
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• 제39권2호
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• pp.289-297
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• 2002

It was shown by L. Polterovich ([3]) that if L is a totally real submanifold of a symplectic manifold $(M,\omega)$ and L is parallelizable then L is normal. So we try to find an answer to the question of whether there is a compatible almost complex structure J on the symplectic vector bundle $TM$\mid$_{L}$ such that $TL{\cap}JTL=0$ assuming L is normal and parallelizable. Although we could not reach an answer, we observed that the claim holds at the vector space level. And related to the question, we showed that for a symplectic vector bundle $(M,\omega)$ of rank 2n and $E=E_1{\bigoplus}E_2$, where $E=E_1,E_2$are Lagrangian subbundles of E, there is an almost complex structure J on E compatible with ${\omega}$ and $JE_1=E_2$. And finally we provide a necessary and sufficient condition for a given embedding into a symplectic manifold to be normal.

• 한국응용과학기술학회지
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• 제17권2호
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• pp.99-104
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• 2000

Physical properties and performance characteristics of sodium salt of several pure N-acyl amino acids made from glycine, dl-alanine, sarcosine, dl-valine, l-leucine, l-aspartic acid and l-lysine seven long chain fatty acids are reported. The effect of acyl chain length and the differences in the structure of constituent amino acid of seven homologous series of amide intermediate linked carboxylate surfactant of this class on the properties are discussed.

• 식물분류학회지
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• 제49권4호
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• pp.300-318
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• 2019

조록싸리(Lespedeza maximowiczii) 내에 많은 종내분류군들 및 근연분류군과의 잡종들이 기록되었지만, 이들의 분류학적 실체에 대해서는 학자들간에 이견이 있다. 본 연구는 조록싸리와 근연분류군간 잡종인 지리산싸리(L. chiisanensis), 진도싸리(L. patentibicolor) 및 조록싸리의 종내분류군인 털조록싸리(var. tomentella), 늦싸리(var. elongata), 삼색싸리(var. tricolor)의 실체를 규명하기 위해, 외부형태를 관찰하고 microsatellite를 이용하여 유전적 구조를 분석하였다. 연구 결과 털조록싸리와 늦싸리의 꽃과 잎의 형태는 조록싸리의 변이폭에 속했고, 유전적으로도 두 분류군이 조록싸리와 같이 묶였다. 삼색싸리는 꽃의 구조와 색에서 근연종인 L. buergeri와 유사한 반면 소엽 정단부와 소포엽의 형태는 조록싸리와 가까웠다. 유전적 구조에서도 삼색싸리의 개체들은 조록싸리와 L. buergeri의 계통이 혼합된 형태를 보이거나(K = 3), 독립되었다(K = 5). 잡종들의 경우, 지리산싸리의 꽃과 잎의 형태는 조록싸리와 구별되지 않는 반면, 진도싸리의 꽃 형질은 싸리(L. bicolor)의 변이폭에 속했는데, 유전적 계통도 각각 조록싸리와 싸리로 지정되었다. 본 연구결과를 종합하여 저자들은 털조록싸리와 늦싸리를 조록싸리의 품종, f. friebeana (Schindl.) D. P. Jin, J. W. Park & B. H. Choi로 처리하였는데, 이는 L. friebeana가 var. tomentella 보다 먼저 발표되었기 때문이다. 또한 삼색싸리는 독립종, L. tricolor (Nakai) D. P. Jin, J. W. Park & B. H. Choi 로 처리하였고, 지리산싸리는 조록싸리의 이명으로 처리하였다. 한편 진도싸리는 싸리의 이명으로 판단된다.