• 대한원격탐사학회지
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• 제33권3호
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• pp.301-311
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• 2017

에어로솔의 광학특성과 연직고도는 태양 복사의 반사와 흡수과정을 통하여 지구복사수지에 영향을 미치게 된다. 본 연구에서는 복사전달모델과 위성관측자료를 이용하여 동북아시아 지역에서 구름의 존재 시 에어로솔 층에 의한 복사특성을 분석하였다. 복사전달 모의 결과는 구름이 하부에 존재하는 경우에 에어로솔 층의 고도가 높아짐에 따라 대기 온난화 효과가 증가하였다. 이러한 관계는 에어로솔의 광 흡수성이 커질수록, 지표 반사도가 증가할수록 비례하는 경향을 나타내었다. 그리고 연구대상지역 ($20-50^{\circ}N$, $110-140^{\circ}E$)에서 주요 에어로솔 이벤트 사례에 대하여, UV Absorbing Aerosol Index (AAI) derived from Total Ozone Mapping Spectrometer (TOMS), cloud parameters derived from the Moderate Resolution Imaging Spectro-radiometer (MODIS), with Upward Shortwave Flux (USF) Clouds and the Earth's Radiant Energy System (CERES) 위성관측자료를 이용하여 광 흡수성 에어로솔에 의한 영향을 정량적으로 분석하였다. 각 사례에 대한 평균적인 복사효과는 약 6 - 26 %에 해당하는 상향 단파 복사량의 감쇄효과가 나타났다. 이러한 결과는 에어로솔에 의한 직접효과와 간접효과를 정량화 하기 위한 중요성을 설명해 준다.

• 대한임상검사과학회지
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• 제51권4호
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• pp.462-467
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• 2019

최근 수십 년 동안 향기 및 악취 흡입에 의한 후각자극이 인간에게 심리적, 생리적 영향을 미친다는 다양한 연구가 보고되고 있다. 본 연구는 후각자극에 의한 사람 대뇌겉질 신경세포의 전기생리학적 반응성을 조사하고자 하였다. 건강한 남성 12명을 대상으로 아카시아와 부탄올에 의한 후각자극이 알파파의 활동도에 미치는 영향을 정량적으로 분석하였다. 아카시아 향취를 흡입하는 경우는 후각자극이 없는 안정상태의 뇌파에 비해 알파파의 활동도가 유의하게 증가(66.7%)하였고, 부탄올 악취에서는 알파파 활동도의 유의한 감소(33.3%~41.7%)가 관찰되었다. 본 연구는 후각자극에 의하여 대뇌겉질 신경세포의 활동도에 변화가 있을 수 있다는 것을 시사한다. 이러한 결과는 후각인지가 신경계의 기능에 자극효과를 나타낼 수 있다는 것을 의미한다. 즉 본 연구에서 후각자극이 뇌파활동과 기분상태에 영향을 미친다는 결론을 도출할 수 있었다. 이러한 관점에서 향후 중추신경계에 대한 전기생리학적 효과의 영향을 이해하고, 설명하기 위한 추가연구가 필요할 것으로 사료된다.

• 생태와환경
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• 제54권4호
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• pp.315-326
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• 2021

팔당호에서 청수현상 발생은 지점별로 다른 양상을 보였으며, 발생시기는 3~12월로 연중 발생하는 것으로 나타났고, 주로 3~6월에 발생하였다. 청수기 발생빈도는 팔당댐앞, 경안천수역, 남한강수역, 북한강수역 순으로 나타났다. 청수현상 발생시 주요 요인인 투명도, 동물플랑크톤 현존량, Chl-a와 환경요인 상관분석 결과 수리·수문요인인 강우량, 체류시간은 투명도 및 탁도와 유의한 상관관계를 나타내 강우로 인한 체류시간의 변화가 청수현상을 좌우할 수 있는 것으로 나타났다. 또한 투명도는 청수기를 야기하는 것으로 알려진 동물플랑크톤 중 지각류 현존량 및 점유율과 유의한 상관관계를 나타냈으며, 지각류 현존량 및 점유율은 수온과 유의한 상관관계를 나타내 봄철 수온의 상승에 따른 지각류의 발생이 청수현상 발생을 야기할 수 있는 것으로 나타났다. 이에 따라 수리조건이 정체형 호수와 다른 하천형의 호수에서는 청수현상이 결빙기 이후 봄철뿐만 아니라 동일한 수계 내에서도 지점별 특성에 따라 다르게 나타날 수 있으며, 수체가 안정화될 시에 동물플랑크톤(지각류)의 증가, 식물플랑크톤 현존량 감소, 투명도가 증가하는 청수현상이 조건이 충족될 시 계절에 불문하고 연중 발생할 수 있는 것으로 나타났다.

• 항공우주시스템공학회지
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• 제16권6호
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• pp.54-63
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• 2022

최근 다양한 형태의 전기추진 항공기가 개발 중이다. 전기추진 항공기에 장착되는 프로펠러의 위치는 항공기 공력성능에 큰 영향을 미칠 수 있다. 날개 앞에 장착된 프로펠러는 프로펠러 주변과 하류방향으로 복잡한 선회 유동(Swirl Flow)을 발생시킨다. 선회 유동으로 발생하는 올려흐름과 내리흐름은 날개의 유효받음각에 영향을 미친다. 날개의 길이 분포 방향으로 발생하는 유효받음각 분포변화는 날개의 공력 하중분포에 영향을 준다. 본 연구에서는 날개에 장착된 프로펠러의 위치가 변화하면서 발생하는 프로펠러-날개 상호작용이 날개의 공력 하중분포에 미치는 영향을 연구했다. 프로펠러-날개 상호작용이 날개에 미치는 영향을 해석하기 위해, 프로펠러에 의한 선회 유동을 Actuator Disk Theory를 사용하여 나타냈다. VSPAERO를 사용하여 날개에서 발생하는 공력을 계산했다. 본 연구방법을 사용하여 얻은 계산결과는 프로펠러-날개 모델을 사용한 풍동시험 자료와 비교·검증했다. 연구결과 프로펠러와 날개 사이의 거리가 날개의 공력특성에 미치는 영향은 크게 나타났다. 축방향 및 날개길이 방향의 거리 증가는 양항비를 증가시켰다. 프로펠러가 날개 상단에 위치할 경우 더 큰 양항비를 얻을 수 있었다.

• 대한치과보철학회지
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• 제59권4호
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• pp.379-394
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• 2021

목적: 이전 연구에서 치은섬유아세포 혹은 성견 구개 연조직에 trichloroacetic acid (TCA)를 적용하는 것이 세포주기진행 유전자 발현의 변화를 일으키는 것으로 밝혀졌다. 이에 따라 본 연구에서는, hydrophobically modified glycol chitosan (HGC)기반의 나노방출제어시스템을 이용한 TCA 및 상피세포성장인자(EGF)의 순차적 방출시스템에서 이 효과를 검증하기 위하여 다양한 세포주기진행 유전자들의 발현을 규명하였다. 재료 및 방법: TCA와 EGF를 담지하는 HGC기반 나노방출제어시스템을 제작하였다. 실험군은 대조군(CON); TCA-담지형 나노방출제어시스템 투여군(EXP1); TCA- 및 EGF-담지형 나노방출제어시스템 투여군(EXP2)으로 정의되었다. 24시간 및 48시간 배양 시 37개 세포주기 유전자들의 발현을 분석하였다. 영향인자로서의 유전자 및 상관관계에 대해서도 분석하였다. 결과: Cyclins (CCNDs), cell division cycles (CDCs), cyclin-dependent kinases (CDKs), E2F transcription factors (E2Fs), extracellular signal-regulated kinases (ERKs)와 같은 다수의 유전자들과 기타 다른 세포주기 유전자들의 발현이 EXP1과 EXP2에서 상향조절되었다. E2F4, E2F5, GADD45G와 같은 세포주기차단 유전자들의 발현도 상향조절되었으나, 또다른 세포주기차단 유전자인 SMAD4의 발현은 하향조절되었다. 다중회귀분석에서 CCNA2, CDK4 그리고 ANAPC4가 ERK 유전자 발현에 가장 영향력 있는 유전자로 선정되었다. 결론: HGC기반 순차적 나노방출제어시스템을 이용한 TCA 및 EGF의 적용은 다양한 세포주기진행 유전자들의 발현을 상향조절함이 밝혀졌고, 이를 토대로 한 구강연조직증대시스템 개발의 가능성이 확보되었다.

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2000년도 춘계학술강연 및 발표대회 강연 및 발표논문 초록집
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• pp.9-10
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• 2000

An important business-field of world-wide steel-industry is the coating of thin metal-sheets with zinc, zinc-aluminum and aluminum based materials. These products mostly go into automotive industry. in particular for the car-body. into building and construction industry as well as household appliances. Due to mass-production, the processing is done in large continuously operating plants where the mostly cold-rolled metal-strip as the substrate is handled in coils up to 40 tons unwind before and rolled up again after passing the processing plant which includes cleaning, annealing, hot-dip galvanizing / aluminizing and chemical treatment. In the liquid Zn, Zn-AI, AI-Zn and AI-Si bathes a combined action of corrosion and wear under high temperature and high stress onto the transfer components (rolls) accounts for major economic losses. Most critical here are the bearing systems of these rolls operating in the liquid system. Rolls in liquid system can not be avoided as they are needed to transfer the steel-strip into and out of the crucible. Since several years, ceramic roller bearings are tested here [1.2], however, in particular due to uncontrollable Slag-impurities within the hot bath [3], slide bearings are still expected to be of a higher potential [4]. The today's state of the art is the application of slide bearings based on Stellite\ulcorneragainst Stellite which is in general a 50-60 wt% Co-matrix with incorporated Cr- and W-carbides and other composites. Indeed Stellite is used as the bearing-material as of it's chemical properties (does not go into solution), the physical properties in particular with poor lubricating properties are not satisfying at all. To increase the Sliding behavior in the bearing system, about 0.15-0.2 wt% of lead has been added into the hot-bath in the past. Due to environmental regulations. this had to be reduced dramatically_ This together with the heavily increasing production rates expressed by increased velocity of the substrate-steel-band up to 200 m/min and increased tractate power up to 10 tons in modern plants. leads to life times of the bearings of a few up to several days only. To improve this situation. the Mechanical Alloying (MA) TeChnique [5.6.7.8] is used to prOduce advanced Stellite-based bearing materials. A lubricating phase is introduced into Stellite-powder-material by MA, the composite-powder-particles are coated by High Energy Milling (HEM) in order to produce bearing-bushes of approximately 12 kg by Sintering, Liquid Phase Sintering (LPS) and Hot Isostatic Pressing (HIP). The chemical and physical behavior of samples as well as the bearing systems in the hot galvanizing / aluminizing plant are discussed. DependenCies like lubricant material and composite, LPS-binder and composite, particle shape and PM-route with respect to achievable density. (temperature--) shock-reSistibility and corrosive-wear behavior will be described. The materials are characterized by particle size analysis (laser diffraction), scanning electron microscopy and X-ray diffraction. corrosive-wear behavior is determined using a special cylinder-in-bush apparatus (CIBA) as well as field-test in real production condition. Part I of this work describes the initial testing phase where different sample materials are produced, characterized, consolidated and tested in the CIBA under a common AI-Zn-system. The results are discussed and the material-system for the large components to be produced for the field test in real production condition is decided. Outlook: Part II of this work will describe the field test in a hot-dip-galvanizing/aluminizing plant of the mechanically alloyed bearing bushes under aluminum-rich liquid metal. Alter testing, the bushes will be characterized and obtained results with respect to wear. expected lifetime, surface roughness and infiltration will be discussed. Part III of this project will describe a second initial testing phase where the won results of part 1+11 will be transferred to the AI-Si system. Part IV of this project will describe the field test in a hot-dip-aluminizing plant of the mechanically alloyed bearing bushes under aluminum liquid metal. After testing. the bushes will be characterized and obtained results with respect to wear. expected lifetime, surface roughness and infiltration will be discussed.

• The Korean Journal of Physiology and Pharmacology
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• 제17권6호
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• pp.493-497
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• 2013

We have recently demonstrated that some anti-diabetic drugs such as biguanide and thizolidinediones administered centrally modulate the blood glucose level, suggesting that orally administered anti-diabetic drugs may modulate the blood glucose level by acting on central nervous system. The present study was designed to explore the possible action of another class of anti-diabetic drugs, glinidies, administered centrally on the blood glucose level in ICR mice. Mice were administered intracerebroventricularly (i.c.v.) or intrathecally (i.t.) with 5 to $30{\mu}g$ of repaglinide or nateglinide in D-glucose-fed and streptozotocin (STZ)-treated models. We found that i.c.v. or i.t. injection with repaglinide dose-dependently attenuated the blood glucose level in D-glucose-fed model, whereas i.c.v. or i.t. injection with nateglinide showed no modulatory action on the blood glucose level in D-glucose-fed model. Furthermore, the effect of repaglinide administered i.c.v. or i.t. on the blood glucose level in STZ-treated model was studied. We found that repaglinide administered i.c.v. slightly enhanced the blood glucose level in STZ-treated model. On the other hand, i.t. injection with repaglinide attenuated the blood glucose level in STZ-treated model. The plasma insulin level was enhanced by repaglinide in D-glucose-fed model, but repaglinide did not affect the plasma insulin level in STZ-treated model. In addition, nateglinide did not alter the plasma insulin level in both D-glucose-fed and STZ-treated models. These results suggest that the anti-diabetic action of repaglinide appears to be, at least, mediated via the brain and the spinal cord as revealed in both D-glucose fed and STZ-treated models.

• Asian Pacific Journal of Cancer Prevention
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• 제15권11호
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• pp.4437-4441
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• 2014

SMAD7 has been identified as a functional candidate gene for colorectal cancer (CRC). SMAD7 protein is a known antagonist of the transforming growth factor beta ($TGF-{\beta}$) signaling pathway which is involved in tumorigenesis. Polymorphisms in SMAD7 may thus alter cancer risk. The aim of this study was to investigate the influence of a SMAD7 gene polymorphism (rs2337107) on risk of CRC and clinicopathological features in an Iranian population. In total, 210 subjects including 105 patients with colorectal cancer and 105 healthy controls were recruited in our study. All samples were genotyped by TaqMan assay via an ABI 7500 Real Time PCR System (Applied Biosystems) with DNA from peripheral blood. The polymorphism was statistically analyzed to investigate the relationship with the risk of colorectal cancer and clinicopathological properties. Logistic regression analysis revealed that there was no significant association between rs2337107and the risk of colorectal cancer. In addition, no significant association between genotypes and clinicopathological features was observed (p value>0.05). Although there was not any association between genotypes and disorder, CT was the most common genotype in this population. This genotype prevalence was also higher in the patients with well grade (54.9%) and colon (72.0%) tumors. Our results provide the first evidence that this polymorphism is not a potential contributor to the risk of colorectal cancer and clinicopathological features in an Iranian population, and suggests the need of a large-scale case-control study to validate our results.

• 한국중재학회지:중재연구
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• 제27권1호
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• pp.59-84
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• 2017

The effects of an arbitration agreement depend on the legislative policy of the nation where arbitral awards are made and where awards are worked out in the private procedures. According to the main body of Article 35 of the Korean Arbitration Act, arbitral awards have the same effects on the parties as the final and conclusive judgment of the court. This is only possible if the awards are formed by satisfying all the legal requirements, have gone into effect, and have become final and conclusive. It is for the legal stability and the effectiveness of the settlement of disputes that the Act grants arbitral awards. While investigating the effects of an arbitral award, the character of the arbitration in which the party's autonomy applies should be considered, along with the substance of the disputes which parties intend to resolve by an arbitration agreement. The proviso of Article 35, which was added in the 2016 Act, says that the main body of the Article shall not apply if recognition or enforcement of arbitral awards is refused under Article 38. Two stances have been proposed in interpreting the proviso. One of them is that there are grounds for refusing the recognition and enforcement of the awards. The other one is that the ruling of the dismissal of a request for enforcement has been final and conclusive. According to the former, it is really unexplained as to its relations with the action for setting aside arbitral awards to court and the distinction between nullity and revocation, and so on. Therefore, its meaning must be comprehended on the basis of the latter so that the current Act system with revocation litigation could be kept. The procedures of setting aside, recognizing, and enforcing arbitral awards are independent of one another under the Act. It is apprehended that the duplicate regulations may lead to the concurrence or contradiction of a court's judgment and ruling. Thus, we need to take proper measures against the negative sides by interfacing and conciliating these proceedings.

• Molecular & Cellular Toxicology
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• 제4권1호
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• pp.31-44
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• 2008

The forced swim test (FST) is the most widely used model for assessing potential antidepressant activity. Although it has been shown that lateral septum is involved with the FST-related behavior, it is not clear whether antidepressant treatments could alter the FST-induced gene expression profile in the lateral septum. In the present study, the gene expression profiles in response to FST and reboxetine pretreatment were observed in the lateral septum of rats. Reboxetine is known as a most selective serotonin norepinephrine reuptake inhibitor. In addition, we compared the changes in gene expression profile between reboxetine response and nonresponse groups, which were determined by counting FST-related behavior. After FST, lateral septum from controls and reboxetine pretreated group were dissected and gene expression profiles were assessed using an Affymetrix microarray system containing 15,923 genes. Various genes with different functions were changed in reboxetine response group compared with reboxetine nonresponse group, In particular, pleiotrophin, orexin receptor 2, serotonin 2A receptor, neuropeptide Y5 receptor and thyroid hormone receptor $\beta$ were decreased in reboxetine response group, but Lim motif-containing protein kinase 1 (Limk1) and histone deacetylase 1 (HDAC1) were increased. Although further studies are required for direct roles of these genes in reboxetine response, the microarray may provide tools to find out potential target genes and signaling pathways in antidepressant response.