• 미생물학회지
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• 제44권1호
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• pp.63-68
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• 2008

참외 경작지 토양으로부터 순수 분리된 선충포식성 곰팡이 Kan-23 균주는 배양 30일 이후에 분생포자가 형성되는 증식이 매우 더딘 특성을 나타내었다. 주사전자현미경(SEM)을 이용하여 Kan-23 균주의 미세형태 구조를 관찰한 결과 분생포자병의 각 가지마다 $5{\sim}10$개의 분생포자를 형성하였으며, 분생포자는 3개의 격막을 형성하고 타원형을 나타내었고, 수축성 고리형태(constricting ring)의 포식 구조체를 형성하는 특징을 나타내었다. 다양한 배지를 이용하여 포식 구조체의 형태학적 특성을 비교 검토한 결과 GPA 배지에서 2배 이상 크기의 대형 수축성 고리 형태의 포식 구조체를 형성하는 특징을 나타내었다. Kan-23 균주의 rDNA의 ITS 영역의 염기서열을 분석한 결과, Drechslerella 속의 계통군에 속하였으며, 특히 Drechslerella brochopaga (U51950)와 99%의 높은 염기서열 유사도를 나타내어 Drechslerella brochopaga로 동정되어 국내 미기록종임이 확인되었다.

• Korean Chemical Engineering Research
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• 제43권6호
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• pp.662-667
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• 2005

HMCM-41 중간세공 물질(mesoporous material) 촉매를 사용하여 aryl methallyl ether로부터 의약품과 농약의 주요 중간체인 2,3-dihydrobenzofuran 유도체를 합성하였다. 산점 농도가 촉매 활성에 미치는 영향을 비교하기 위하여 Si/Al 몰비가 40과 50으로 다른 촉매를 제조하였으며, aryl methallyl ether에 다양한 치환기를 도입하여 벤젠 고리의 전자 밀도가 전환율과 수율에 미치는 효과를 조사하였다. 산점이 많아질수록 전환율은 높아졌으나, 2,3-dihydorbenzofuran 유도체의 수율과 직접 연관짓기는 어려웠다. 전자공여기의 치환으로 벤젠 고리의 전자 밀도가 높아지면 claisen 자리 옮김 반응이 빨라져서 2,3-dihydrobenzofuran 유도체가 많이 생성되었다. 반면, 전자흡인기가 치환되어 벤젠 고리의 전자 밀도가 낮아지면 산 촉매에 의해 aryl methallyl ether 분해 반응이 촉진되어 2,3-dihydrobenzofuran 유도체 대신 phenol 유도체가 생성되었다.

• 한국산림과학회지
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• 제10권1호
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• pp.41-45
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• 1970

본연구(本硏究)는 경제적(經濟的)으로 중요(重要)한 한국산외래수종(韓國產外來樹種)의 목재(木材)에 관(關)한 식별(識別)을 위(爲)해서 수행(遂行)되었는데 사용(使用)한 시험목(試驗木)은 광양(光陽)과 수원지방(水原地方)에 생장(生長)한 20개수종(個樹種)을 택(擇)하였다. 육안적특성(肉眼的特性)의 조사항목(調査項目)은 주(主)로 연륜(年輪), 춘재(春材)로부터 추재부(秋材部)로의 이행(移行), 관공형(管孔型)과 배열(排列), 변심재(邊心材), 재색(材色), 향기(香氣)와 미(味), 수지구(樹脂溝), 유조직(柔組織)과 수선등(髓線等)을 관찰(觀察)하였고 조사(調査) 하였으며 현미경적특징(顯微鏡的特徵)은 도관(導管), 가도관(假導管), 대섬유(大纖維), 수선유세포(髓線柔細胞), 수직유세포(垂直柔細胞) 및 세포간구(細胞間溝)의 요소(要素)와 그들의 구성상태(構成狀態)에서 관찰할 수 있는 특징(特徵)을 관찰(觀察)하였고 측정(測定)하였다. 이상과 같이 관찰(觀察)및 측정(測定)된 결과(結果)는 종합(綜合)되었고 이들 결과(結果)를 바탕으로 하여 목재식별(木材識別)을 위(爲)해서 육안적검색표(肉眼的檢索表)와 현미경적검색표(顯微鏡的檢索表)를 원문(原文)과 같이 작성(作成) 하였다.

• 한국의상디자인학회지
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• 제11권1호
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• pp.1-16
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• 2009

Ip-yeong or gat-keun decorate heuk-rip, supplementing its simplicity. When the wind blew, a dynamic beauty was created, especially if the gat-keun was made with long straps of jade or silk. Basically, ip-yeong was a practical chin strap to hold the gat tight on the head. Commoners made ip-yeong by folding cotton cloth or fine gauze. However, as available materials became diversified, people used cloth, jade, agate, amber, coral, gold medallion, rock crystal and bamboo as well, juk-yeong, which was made with bamboo, became popular especially when Heungsun Daewon-gun, the father of King Kojong, decreed that people wear simple clothes. Most records concerning ip-yeong in Chosun-wangjo-shillok, the authentic record of the Joseon Dynasty, are related to forbidding a sumptuous life. The book also suggests that ip-yeong was bestowed by the king or was offered to foreign diplomats as gifts. Ip-yeong doesn't seem to be a unique system for Korea. Based on portraits or paintings where ip-yeong can be found, it seems to have been widely used during the Yuan dynasty and the Goryeo dynasty. The system disappeared in China as the Ming Dynasty was established, but it remained in use in the Korean Goryeo dynasty and through the Joseon. Literature suggests that the same materials were used for ip-yeong from the beginning of Joseon to the end of the dynasty. Guyeongja refers to a ring that connects an ipja to a chin strap. Guyeongja made with silver, bronze and jade still remain. In gungjungbalgi, the royal court inventory book, records of imogarye can be found (1882), where ten pairs of pure gold strap rings and ten pairs of gold-plated ones were used for a royal wedding.

• 한국위성정보통신학회논문지
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• 제11권2호
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• pp.29-35
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• 2016

High-availability seamless redundancy (HSR) 은 두 개의 복제된 프레임을 각각의 경로로 전송하여 거의'0'시간에 고장을 복구하는 실시간 고장 허용 프로토콜이다. 그러므로 HSR은 스마트 그리드 통신과 같은 첨단 실시간 네트워크에 사용이 가능하다. 그러나 HSR 프로토콜은 고장 복구를 위해 생성되는 불필요한 트래픽이 목적지 노드가 포함되지 않은 하부 네트워크에도 지속적으로 순환하는 주요 단점이 있으며, 이는 네트워크의 트래픽 성능을 저하시키고, 네트워크의 활용 자원을 감소시키는 원인이 된다. 이러한 단점을 보완하기 위해, 효율적인 두 가지 알고리즘, Quick Removing (QR) 과 Port Locking (PL) 이 발표된 바 있다. 본 논문은 QR과 PL을 결합한 새로운 알고리즘, QRPL의 구현 가능성 및 그 성능을 수학적으로 해석 제시하고 시뮬레이션으로 확인하였다. 그 결과 다수의 하위 ring이 연결된 HSR 네트워크에서 유니캐스트 트래픽을 적용시, 표준 HSR, QR, 또는 PL 알고리즘을 개별로 사용하는 것보다, QRPL 알고리즘을 사용하는 경우 성능이 크게 향상됨을 확인하였다.

• Tribology and Lubricants
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• 제32권5호
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• pp.141-146
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• 2016

The diketopyrrolopyrrole (DPP) pigment is a bicyclic 8-π-electron system containing two lactam units. Typical DPP derivative pigments have melting points of over 350°C and very low solubility in most solvents, and show absorption in the visible region with a molar extinction coefficient of 33,000 dm²mol⁻¹ and strong photoluminescence with maxima in the range 500–600 nm. X-ray structure analyses of DPP show that the whole molecule is almost in one plane. The phenyl rings are twisted out of the heterocyclic plane and the intermolecular hydrogen bonding between neighboring lactam NH and carbonyl units influences the structure of the DPP pigment in the solid state. In this study, mono-N-alkylation and mono-N-arylation were undertaken for Pigment Red 264 or Pigment Orange 73 with alkyl halide and aryl halide, respectively, in the presence of sodium tert-butoxide as a base catalyst to improve the solubility of DPP pigments and their application as CO₂ indicators. The synthetic yield was in the range 11–88%. The indicator dyes are highly soluble in organic solvents and shows pH-dependent absorption (λ_max 501 and 572 nm for the protonated and deprotonated forms, respectively) and emission (λ_max 524 and 605 nm for the protonated and deprotonated forms, respectively) spectra. The mono-N-alkylated and mono-N-arylated DPP pigment was identified by ¹H-NMR (¹H-Nuclear Magnetic Resonance Spectrometer), FT-IR (Fourier Transform Infrared Spectroscopy), and MS (Mass Spectrometry). According to the results of color and hue properties obtained by a color matching analyzer, the synthesized DPP pigment material can be used as a CO₂ indicator.

• 한국정밀공학회지
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• 제15권8호
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• pp.17-25
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• 1998

Aluminum alloys have low density, relatively high strength and yield strength, good plasticity, good machinability, and high corrosion and acid resistance. Therefore, they are suitable for large containers for the food, chemical and other industries. Large containers are often bodies of revolution consisting of shell courses, stiffening rings, heads and other elements joined by annular welds. Larger containers have longer welds and require greater leak-tightness and higher weld mechanical properties. The LNG tank consists of aluminum plates with various sizes, so its construction should by divided by several sections. Moreover, each section has its own sub-section consisted of several aluminum plates. To guarantee the quality of huge LNG tank, therefore, the precise control of plate dimension should by urgently needed in conjunction with the appropriate selection of process parameters such as cutting speed, depth of cut, rotational speed and so on. In this paper, a manufacturing system was developed to implement automatic circular tracking in height direction and automatic circular interpolation in depth of cut direction. Also, the neural network based on the backpropagation algorithm was used to predict the cutting quality and motor load related with the life time of the developed system. It was revealed that the manufacturing system and the neural network could be effectively applied to the bevelling process and to predict the quality of machined area and the motor load.

• 한국통신학회논문지
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• 제19권7호
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• pp.1390-1406
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• 1994

본 논문은 로컬 엑세스 컴퓨터 네트워크를 설계할 때 발생되는 문제의 하나로 네트워크의 평균 지연 시간을 고려한 최소 비용 루프 설계 문제(DMCLP-Delay constrained Minimum Cost Loop Problem)를 다룬다. 이 문지는 종단 사용자의 트래픽 요구량을 만족시키는 링의 집합을 구하는 것으로 목적 함수는 전체라인 비용을 최소화하는 것이다. 본 논문에서는 하나의 링이 서비스할 수 있는 노드의 수가 제한되어 있으며 동시에 네트워크의 평균 지연 시간이 원하는 시간이내이어야 한다는 제약 조건하에서 이 문제에 대한 2단계-휴리스틱 알고리즘을 제안한다. 이 알고리즘은 기존의 최소 비용 루프 설계(MCLP) 알고리즘에 의한 클러스터와 본 논문에서 제안한 trade-off criterion를 이용하여 유도된다. 실제 시뮬레이션의 결과, 본 논문에서 제안한 알고리즘은 수정된 기존의 MCLP 알고리즘보다 우수한 해를 제공하며 아울러 비교적 짧은 실행 시간을 갖는다.

• Journal of Chest Surgery
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• 제28권12호
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• pp.1079-1095
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• 1995

Recently endogenous digitalis-like substances were found in the blood of various cardiovascular diseases and they have been considered one of the causes of evoking hypertension. However, the mechanism of endogenous digitalis-like substances-induced hypertension is not clarified yet. Therefore, the effects of Na-K pump inhibition on the contractility of vascular smooth muscle[conduit and resistant artery were investigated, using organ bath and bioassay experiment. Aortic and carotid arterial rings[conduit artery and the branches of brachial and superior mesenteric artery[resistant artery were used to find the effect of Na-K pump inhibition. The results obtained were as followes;The magnitudes of contractions induced by norepinephrine, serotonin, or acetylcholine in all these arteries were significantly increased by the inhibition of Na-K pump. The increased contractile responses to these agonists, especially to serotonin, were much more prominant in resistant arteries. Nitroprusside-induced relaxations were attenuated by Na-K pump inhibition and there were no significant differences in the effects of Na-K pump inhibition on nitroprusside-induced relaxations of these blood vessels. Endothelium-dependent relaxation was suppressed by the inhibition of Na-K pump, especially by the administration of ouabain, and this inhibitory effect was much more prominent in the branches of superior mesenteric artery, compared with other arteries. In the branches of superior mesenteric arteries, endothelium-dependent relaxation was completely blocked by ouabain. The release of EDRF was partially suppressed by Na-K pump inhibition.From the above results, it is suggested that the hypertension due to the increase in vascular resistance can be evoked by the inhibition of Na-K pump and endogenous digitalis-like substances induce hypertension through this mechanism.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2010년도 제39회 하계학술대회 초록집
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• pp.89-89
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• 2010

The atomic structure of Sb/Si(5 5 12)-$2{\times}1$ surface, deposited at room temperature (RT) and post-annealed, has been identified by scanning tunneling microscopy and the corresponding interface has been studied by synchrotron core-level photoemission spectroscopy. With 0.3-nm Sb deposition at RT and postannealing at $600^{\circ}C$, the surface has been facetted to (225)-$2{\times}1$ and (112)-$1{\times}1$, and its Si 2p has shown that all the Si 2p surface components have disappeared, while the single Sb-Si interfacial component has appeared. Such results indicate that all of surface Si atoms are replaced by Sb atoms and the charge is transferred from Si to passivating Sb-atoms at the top layer. With subsequent postannealing up to $700^{\circ}C$, the surface has been facetted to (113)-$2{\times}2$ and (335)-$4{\times}2$, still having Sb-Si interfacial component and partially re-exposed Si surface components. From the present study, the role of surfactant atom, Sb, as well as the thermal-stabilization of Sb-passivated high-index Si surface will be exposed. Especially, the key role of the Sb/Si(113)-$2{\times}2$, composed of Rebonded-Dimer-Rebonded atom 1D structures, for stabilization will be discussed.