• Restorative Dentistry and Endodontics
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• 제38권4호
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• pp.194-203
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• 2013

Objectives: To investigate the effect of enamel matrix derivative (EMD) on periodontal healing of replanted teeth in animal models. Materials and Methods: The authors searched MEDLINE, PubMed, EMBASE, Cochrane Library, Web of Knowledge and Scopus for articles published up to Oct 2012. Animal studies in which EMD was applied in transplanted or replanted teeth with adequate controls and histological data were considered. Normal periodontal healing or root resorption determined by histology after EMD was applied in replanted teeth with adequate controls was used as outcome measures. The following search strategy was used: ('Emdogain' OR 'enamel matrix proteins' OR 'enamel matrix derivative') AND ('avulsion' OR 'transplantion' OR 'autotransplantation' OR 'replantation'). Results: Six animal studies were included in the final review. There was great heterogeneity in study design among included studies. Two studies with similar study designs were identified and analyzed by a meta-analysis. The pooled estimates showed a significantly higher normal healing and surface resorption and significantly less inflammatory and replacement resorption in EMD-treated groups compared with non-EMD-treated groups. Conclusions: With the limitations of this systematic review, the use of EMD led to greater normal periodontal healing and surface root resorption and less inflammatory and replacement root resorption in the presence of periodontal ligaments. However, no definite conclusion could be drawn with regard to the effect of EMD on periodontal healing and root resorption when no periodontal ligaments exist.

• 한국환경과학회지
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• 제29권1호
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• pp.15-23
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• 2020

The determination of soil characteristics is important in the simulation of rainfall runoff using a distributed FLO-2D model in catchment analysis. Digital maps acquired using remote sensing techniques have been widely used in modern hydrology. However, the determination of a representative parameter with spatial scaling mismatch is difficult. In this investigation, the FLO-2D rainfall-runoff model is utilized in the Yongdam catchment to test sensitivity based on three different methods (mosaic, arithmetic, and predominant) that describe soil surface characteristics in real systems. The results show that the mosaic method is costly, but provides a reasonably realistic description and exhibits superior performance compared to other methods in terms of both the amount and time to peak flow.

• International Journal of Safety
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• 제3권1호
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• pp.20-26
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• 2004

The system considered in this model consists of a single, semi- transparent, diesel fuel droplet, which is immobile in the heating area and surrounded by a quiescent air. A uniform external radiation field surrounds the droplet. Results from mathematical simulation suggest that because of the higher surface temperature, the external radiative heating of the droplet can promote an earlier ignition of the fuel vapour/air mixture. The radiative heating of the droplet increases the mass transfer from the droplet to the surrounding gas-phase, thus, decreasing the heterogeneity of the fuel droplet/air system.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2004년도 Proceedings of ISRS 2004
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• pp.57-59
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• 2004

This paper reports the observation of the interferometric synthetic aperture radar (InSAR) phase anomaly on a newly reclaimed mudflat, Hwaong, in west coast of Korea, detected by a series of Radarsat-l SAR data obtained mostly during 2003. The observed phase anomaly could be from subsidence of mud land caused by volumetric contraction of mud in dry season. This process must have been initiated from March 2002 when tidal water supply to this region was permanently blocked by the newly constructed embankment. The maximum subsidence rate measured from InSAR signal is about 3 cm per month. The local heterogeneity of the subsidence rate over the reclaimed mudflat may indicate various mud composition, surface-subsurface hydrological processes, or subsurface information of the mud and basement rock structure. In-situ measurement must follow to support this observation from space.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2006년도 총회 및 춘계학술발표회
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• pp.282-285
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• 2006

This study is to present the method for estimating groundwater recharge with temporal-spatial variability using the SWAT model which can represent the heterogeneity of the watershed. The SWAT model can simulate daily surface runoff, evapotranspiration, soil storage, recharge, and groundwater flow within the watershed. The model was applied to Musimcheon watershed located in the upstream of Mihocheon watershed. Hydrological components were determined for the period 2001 - 2004, and the validity of the results was tested by comparing the estimated runoff with the observed runoff data at the outlet of the catchment. The results of temporal and spatial variations of recharge were presented, This study suggests that variations in recharge can be significantly affected by subbasin slope as well as land use changes.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2003년도 총회 및 춘계학술발표회
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• pp.287-291
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• 2003

To delineate the internal structures of alluvial aquifer, high resolution seismic and GPR methods were adopted in Buyeo Gunsu-Ri area. The result of seismic refraction survey shows the water table of the aquifer and the result of seismic reflection reveals the basement and somewhat dominant internal structures of alluvial aquifer. The internal heterogeneity due to variations in channel behavior can be delineated using GPR survey. GPR profiles for the point bar deposits near Buyeo county reveals two different stratigraphic units the lower inclined heterogeneous strata and the upper horizontally stratified strata. According to the increase of demand for water resource using artificial recharge in alluvium, it is believed that the information acquired by high resolution geophysical methods will have an important roles for the effective and sustainable development and usage of groundwater in alluvial aquifer.

• 마이크로전자및패키징학회지
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• 제6권1호
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• pp.39-49
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• 1999

Monolayer 두께의 불화된 유기박막의 특성을 접촉각 측정을 통해 분석 하였다. 정접촉각을 표면장력의 다른 세 가지의 극성(water, formamide), 비극성(diiodomethane) 용액을 이용하여 Teflon, Spin coating된 FC막, 기상증착된 PFDA와 FC막위에 측정하였다. Aluminum위에 증착된 불화 유기박막이 물에 대해 $130^{\circ}$가 넘는 가장 큰 정접촉각을 나타내었다. 반면에 산화막위에 증착된 유기박막은 $70^{\circ}$미만의 낮은 접촉각을 갖었다. Teflon은 $108^{\circ}$, Spin coating된 막은 $121^{\circ}$로 측정되었다. 이들 측정된 값을 이용 Lewis acid/base 이론에 적용 박막의 표면에너지를 계산한 결과 Teflon의 경우는 18 dynes/cm, Spin coating된 유기박막은 8.4 dynes /cm의 낮은 에너지 값이 계산되었다. 실리콘과 산화막위에 증착된 유기박막은 상대적으로 높은 31~35 dynes /cm의 값을 나타내었으나 aluminum위에 증착된 막에서는 Lewis base 항이 큰 음수 값을 갖는 이례적인 경우가 발생하였다. 이때 음수값을 무시한 경우 계산된 aluminum 상의 증착된 유기박막의 표면에너지 PFDA가 13dynes / cm 이였다. 이는 동접촉각과 AFM 측정결과 다른 표면과는 다르게 aluminum강의 유기박막의 비균질성과 표면의 높은 거칠기에 기인함을 알 수 있었다.

• 한국자동차공학회논문집
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• 제14권3호
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• pp.125-132
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• 2006

Transient kinetics of $NH_3$ adsorption/desorption and of SCR(selective catalytic reduction) of NO with $NH_3$ were studied over vanadium based catalysts, such as $V_2O_5/TiO_2$ and $V_2O_5-WO_3/TiO_2$. In the present catalytic reaction process, NO adsorption is neglected while $NH_3$ is strongly chemisorbed on the catalytic surface. Accordingly, it is ruled out the possibility of a reaction between strongly adsorbed $NH_3$ and NO species in line with the hypothesis of an Eley-Rideal mechanism. The present kinetic model assumes; (1) non-activated $NH_3$ adsorption, (2) Temkin-type $NH_3$ coverage dependence of the desorption energy, (3) non-linear dependence of the SCR reaction rate on the $NH_3$ surface coverage. Thus, the surface heterogeneity for adsorption/desorption of $NH_3$ is taken into account in this model. The present study extends the pure chemical kinetic model based on a powdered-phase catalytic system to the chemico-physical one applicable to a realistic monolith reactor.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2020년도 학술발표회
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• pp.125-125
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• 2020

European Space Agency's Sentinel-1 has an improved spatial and temporal resolution, as compared to previous satellite data such as Envisat Advanced SAR (ASAR) or Advanced Scatterometer (ASCAT). Thus, the assumption used for low-resolution retrieval algorithms used by ENVISAT ASAR or ASCAT is not applicable to Sentinel-1, because a higher degree of land surface heterogeneity should be considered for retrieval. The assumption of homogeneity over land surface is not valid any more. In this study, considering that soil roughness is one of the key parameters sensitive to soil moisture retrievals, various approaches are discussed. First, soil roughness is spatially inverted from Sentinel-1 backscattering over Yanco sites in Australia. Based upon this, Artificial Neural Networks data (feedforward multiplayer perception, MLP, Levenberg-Marquadt algorithm) are compared with Fractal approach (brownian fractal, Hurst exponent of 0.5). When using ANNs, training data are achieved from theoretical forward scattering models, Integral Equation Model (IEM). and Sentinel-1 measurements. The network is trained by 20 neurons and one hidden layer, and one input layer. On the other hand, fractal surface roughness is generated by fitting 1D power spectrum model with roughness spectra. Fractal roughness profile is produced by a stochastic process describing probability between two points, and Hurst exponent, as well as rms heights (a standard deviation of surface height). Main interest of this study is to estimate a spatial variability of roughness without the need of local measurements. This non-local approach is significant, because we operationally have to be independent from local stations, due to its few spatial coverage at the global level. More fundamentally, SAR roughness is much different from local measurements, Remote sensing data are influenced by incidence angle, large scale topography, or a mixing regime of sensors, although probe deployed in the field indicate point data. Finally, demerit and merit of these approaches will be discussed.

• 고전문학과교육
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• 제38호
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• pp.201-238
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• 2018

다양한 문화의 시대에 필요한 상호문화능력을 신장하기 위한 방법으로 마달레나 드 카를로 (De Carlo, Maddalena)의 구술성에 주목하여, 한국에 거주하는 이주민이 구술한 설화 자료를 바탕으로 '상징적 표상'이 생성하는 '다양한 가치'를 바탕으로 상대적 감각을 키워낼 수 있는 교육요소와 교육내용을 구체적으로 제시했다. 카를로의 이론을 바탕으로 다양한 문화와 접속하고 공감하고 소통하는 데, 한국에서 구술된 이주민 설화가 기여할 수 있는 방법 중에 하나로 서사적 화두를 통한 문화적 감응력의 확장을 교육요소로 논했다. 이를 6단계로 체계화했다. 1단계 이주민 구술 설화 자료 듣기, 2단계 기억에 각인되는 이질적 화소 찾기, 3단계 이질적 화소로 상징된 대립자질의 의미 파악하기, 4단계 핵심화소가 들어간 서사적 화두 생성하기, 5단계 서사적 화두로 상징적 표상이 내포하는 가치 생성하기, 6단계 삶의 가치를 문화적 상징으로 확장하기다. 3장에서는 이 6단계로 이주민 설화의 교육내용을 적용했다. 수업은 상호문화에서 동질적 결합에 대한 욕망의 한계를 인지하고, 이질성으로 인한 소통의 장벽을 허무는 것과 표면과 이면의 사유를 통해 이질적인 것과 어떻게 관계를 생성할 수 있을지를 생각해 보는 내용으로 구성했다. 인도네시아 설화인 <뒤집어진 배산과 엄마산>은 한국설화는 아니지만 전 세계적으로 많이 알려진 <오이디푸스>신화로 비교하면서 '뒤집어진 배산'이라는 이질적인 화소가 지니는 상징적 표상이 무엇인가를 풀어냈다. 이때 6단계 상징체계를 문화적으로 확장해 갈 때, '뒤집어진 배'에 나타나는 근친상간의 욕망을 문화적으로 동질적인 것과의 결합을 추구하다 생긴 고착으로 해석해 보았다. 캄보디아 설화인 <소녀와 호랑이>는 한국의 <혹부리 영감>과 같은 모방담구조의 이야기인데, '호랑이'라는 화소를 보통 인간과 다른 동물성으로 상징되는 이질적 존재와 어떻게 관계를 맺을지를 문화적으로 확장해서 상호문화능력을 신장할 서사적 화두를 생성하였다. 베트남 설화인 <코코넛 바가지>는 한국의 <구렁덩덩신선비> 등과 비슷하게 표면과 이면에 대한 다양한 사유를 이끌어내는 설화로 이질적인 타인과 어떻게 관계를 형성해야하며, 그렇게 형성된 관계가 삶에 어떤 성장을 가지고 오게 하는가를 살펴보게 하는 방향의 해석이다. 설화의 핵심화소가 형성하는 대립자질로 서사적 화두를 생성하고 감응한다면, 이주민 설화로 낯설고 이질적인 문화와 관계를 형성하며 새로운 삶의 가능성으로 자신을 구성해 갈 수 있을 것으로 해석하였다.