• 동력기계공학회지
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• 제8권3호
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• pp.30-35
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• 2004

In the steel making industries, the continuous casting process has been applied to the number of company because of its economical benefit. Casting rolls are utilized for frictional drive and transport of solidifying slap. Dimensional tolerances, mechanical stability and surface condition of the cast roll can affect both the surface and internal quality of the product being cast. To overcome these problems, the industry is accelerating on the rate of technology improvements. Samples were overlaid on the S45C steel by submerged arc welding process. And the hardness, wear, electrochemical corrosion and oxidation tests were carried out. Test results were that all these materials were satisfying basic requirements of caster rolls. By these results, the addition of 0.1%Nb and 0.15%V increase mechanical properties and tempering resistance by its superior carbide forming characteristics in low carbon $12{\sim}13%Cr$ martensitic stainless steels.

• 한국측량학회:학술대회논문집
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• 한국측량학회 2006년도 춘계학술발표회 논문집
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• pp.181-185
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• 2006

Image co-registration is the process of overlaying two images of the same scene, one of which represents a reference image, while the other is geometrically transformed to the one. In order to improve efficiency and effectiveness of the co-registration approach, the author proposed a pre-qualified area matching algorithm which is composed of feature extraction with canny operator and area matching algorithm with cross correlation coefficient. For refining matching points, outlier detection using studentized residual was used and iteratively removes outliers at the level of three standard deviation. Throughout the pre-qualification and the refining processes, the computation time was significantly improved and the registration accuracy is enhanced. A prototype of the proposed algorithm was implemented and the performance test of 3 Landsat images of Korea showed: (1) average RMSE error of the approach was 0.436 Pixel (2) the average number of matching points was over 38,475 (3) the average processing time was 489 seconds per image with a regular workstation equipped with a 3 GHz Intel Pentium 4 CPU and 1 Gbytes Ram. The proposed approach achieved robustness, full automation, and time efficiency.

• 한국측량학회지
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• 제19권3호
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• pp.273-281
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• 2001

GSIS와 AHP법을 이용하여 삼척지역을 대상으로 산사태 발생 가능성을 분석하였다. 산사태를 유발하는 많은 인자들 중에서 경사도, 경사방향, 지질, 토양, 임상자료들은 기존의 지도자료를 이용하여 입력하여 데이터베이스를 구축하였다. 연구대상지역의 환경적ㆍ지리적 특성을 고려하여 산사태를 유발하는 인자를 결정하였으며, AHP법을 적용하여 유발인자들에 대한 입력값을 결정하였다. 산사태가 발생할 가능성이 있는 지역은 산사태 유발인자들로 만들어진 각각의 레이어를 중첩함으로써 작성되었다. 마지막으로 작성된 도면을 실제 산사태가 발생한 곳과 비교함으로써 산사태 유발인자들이 산사태 발생에 미치는 영향을 알아보았다. 그 결과 삼척지역에서는 토양과 지질적 요소가 가장 많은 영향을 미쳤다는 것을 알 수 있었다.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2005년도 지반공학 공동 학술발표회
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• pp.221-228
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• 2005

The economic growth brought the demand of bridge connected to island and land increasingly in Korea. Therefore, Civil engineer has faced a lot of problem to be considered such as structural stability, economic feasibility and constructional method. At the bridge site to be constructed, the depth of water is about 24m, the thickness of weathered rock overlaying bed rock is thicker than 36m. If open caisson foundation is supported in bed rock, the hight of foundation is about 60m. It is difficult to construct in these conditions. If open caisson foundation is supported in weathered rock, the size of the foundation should be increased. And If we apply the pile foundation, the higher construction cost will be needed. Under the circumstances, we need a new foundation type-composite foundation that is consisted of open caisson and cast-in-place piles. Because the design concept of composite foundation is not presented in Korea Bridge Design Standard, we are willing to clear the bearing behavior of composite foundation by numerical analysis in this paper.

• 한국농공학회논문집
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• 제60권6호
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• pp.55-63
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• 2018

This paper aimed to characterize the spatial and temporal pattern of agricultural drought in Pre-Kharif season using Vegetation Health Index (VHI) and illustrated drought characteristics in Bangladesh during 2001-2015. VHI was calculated from TCI (Temperature Condition Index) and VCI (Vegetation Condition Index) derived from MODIS Terra satellite data, LST (Land Surface Temperature) and EVI (Enhanced Vegetation Index), respectively. The finding showed that all drought-affected areas were experienced by mild, moderate, severe and extreme droughts in several years of Pre-Kharif seasons. Significant drought events were found in the year of 2002 and 2013. On average, Chittagong district covered the largest drought area in all drought stages, and the fraction of drought area was the highest in Sylhet and Rangpur for Pre-Kharif season. Finally, overlaying annual VHI raster maps resulted in that the most vulnerable district to agricultural drought were Sylhet, Rangpur, and Mymensingh in the northern and eastern regions of Bangladesh.

• 한국우주과학회:학술대회논문집(한국우주과학회보)
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• 한국우주과학회 2008년도 한국우주과학회보 제17권2호
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• pp.33.2-33.2
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• 2008

Korea Astronomy and Space Science Institute (KASI) is developing an empirical model for Korean Space Weather Prediction Center (KSWPC). This model predicts the geomagnetic storm strength (Dst minimum) by using only CME parameters, such as the source location (L), speed (V), earthward direction (D), and magnetic field orientation of an overlaying potential field at CME source region. To derive an empirical formula, we considered that (1) the direction parameter has best correlation with the storm strength (2) west $15^{\circ}$ offset from the central meridian gives best correlation between the source location and the storm strength (3) consideration of two groups of CMEs according to their magnetic field orientation (southward or northward) provide better forecast. In this talk, we introduce current status of the empirical storm prediction model development.

• 한국미생물·생명공학회지
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• 제19권4호
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• pp.343-347
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• 1991

Tobramycin 고생산성 변이주를 쉽고 신속하게 선별하 수 있는 screening 방법을 개발하였다. 고농도의 apramycin이 포함된 배지를 사용함으로서 nebramycin 생산성이 낮은 변이주들은 1차적으로 제거할 수 있었다. 모균주인 S. tenerbarius ATCC 17920에는 저지환을 나타내지 못하고 생산성이 향상된 변이주의 경우에만 저지환을 형성하는 strain No.23을 토양으로부터 분리하여 Ps. paucimobilis로 동정하였고 1차 선별된 변이주들 중 tobramycin 생산성이 높은 균주들을 선별하기 위한 피검균으로 사용하였다. 이러한 screening 전략으로 strain No.23에 명확히 저지환을 나타내는 변이주 58주를 얻었고, HPLC를 이용하여 각 변이주의 tobramycin 생산성을 비교 측정한 결과 모균주에 비해 3-8배 생산성이 향상되었음을 확인하였다.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2004년도 Proceedings of ISRS 2004
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• pp.322-325
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• 2004

Recently the domestic technologies to manage forest and to control all related information were developed very rapidly by integrating FGIS (Forest Geographic Information System) and IT (Information technology). However, there still exists a mapping problem for example when overlaying a topography maps scaled in 1/5,000 to a forest type map scaled in 1/25.000. Moreover, there is a greater need to introduce the advanced spatial technologies such as high-resolution satellite image such as IKONOS and GIS to forest. In this study, 3D high-resolution forest mapping system was developed to possibly overlay with all kinds of scale maps and provide the all detailed information by using high-resolution satellite image and GIS. Through this system, all related forest officials could have and maintain the data consistency for their job and share the standard forest database with other post.

• 한국초전도학회:학술대회논문집
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• 한국초전도학회 1999년도 High Temperature Superconductivity Vol.IX
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• pp.222-222
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• 1999

From extensive measurements of the resistance and the dynamic resistance as functions of magnetic field and temperature, we find that the transport in the insulating state beyond the superconductor-insulator (S-I) transition is dominated by bosons(Cooper pairs and/or vortices) and cannot be described by the theory of the fermionic insulating phase. The maximum of the magnetoresistance at B = B$_m$ and the following negative slope in R(B) with increasing field can be explained by the crossover from the "Bose-glass" to the "Fermi-glass" phase as suggested by Paalanen, Hebard, and Ruel. The zero bias peak in dv/dl for biases below the characteristic voltage V$_c$ (or current $I_c$), gives a clue for the assumption of the "dirty boson" model which states that the insulating state above the critical magnetic field is the phase where Cooper pairs are localized due to the Coulomb blockade with a nonvanishing order parameter. The shift to a lower value of the critical magnetic field by overlaying thin Au layer, which is known as a strong spin-orbit scatterer, also supports the bosonic nature of the S-I transition.

• 한국지반공학회논문집
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• 제32권12호
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• pp.33-43
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• 2016

노후관로로 인한 지반내 공동형성과 지반이완 메카니즘을 분석하기 위해 현장시험을 수행하였으며 수치해석을 수행하여 현장시험과 비교하였다. 현장시험은 지반내 인위적인 공동을 만들기 위해 얼음을 이용하였으며, 시간경과에 따른 얼음의 융해로 인해 공동형성과 주변지반의 이완을 확인할 수 있었다. 다짐된 토사의 interlocking에 의한 이완 및 공동형성 거동을 고려하기 위하여개별요소법에 근거한 수치해석 프로그램인 PFC 2D를 이용하였다. PFC의 클럼프(clump) 요소를 도입하여 불규칙 형상의 입자를 모사하였으며, 이를 통해 얻은 공동형성과 지반이완 특성을 현장시험 결과와 비교함으로써 지반내 공동형성 및 거동특성을 파악하였다.