• Proceedings of the Korean Association of Geographic Inforamtion Studies Conference
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• 2010.09a
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• pp.72-76
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• 2010

최근 들어 고해상도 항공영상을 활용한 공간정보의 구축 및 활용 사례가 증가하고 있으며, 기 구축된 공간정보의 정확도 향상을 위한 추가적인 노력이 필요시 되고 있는 실정이다. 이에 본 연구에서는 기존의 피해 전 후 항공영상을 이용한 피해지역 자동추출에 있어 결과물의 정확도 향상을 위하여 토지피복도와의 중첩을 통한 피해항목의 선택적 추출과 자동 추출된 결과물의 오차 제거가 가능하도록 하였다. 연구 대상지역은 2008년 7월 말 국지성 집중호우로 인하여 큰 피해를 입은 경상북도 봉화군 춘양면 일대를 선정하였으며, 집중호우에 상당히 취약하고 당시 사유시설 중 피해액이 가장 컸던 농경지에 대해 본 연구를 시범 적용하였다. 결과적으로 토지피복분류를 통해 피해 전 후 영상의 해상도 차이와 시계열적인 차이로 인해 발생하는 자동추출 결과물의 잡음 제거가 가능하였으며, 항공영상정보와 달리 육안으로 피해 항목의 선별이 어려운 자동추출 결과물에서 피해항목의 선별이 가능하였다. 이는 나아가 피해지역의 피해액 산출에 있어 보다 정확한 계산이 가능하게 하며, 추후 국가적 피해조사 사업에 있어 신뢰성 높은 피해정보 생산에 큰 기여를 할 것으로 사료된다.

• Fire Science and Engineering
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• v.18 no.4
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• pp.72-77
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• 2004

In this paper, we studied on the short-circuit process, surface structure, and component variation of vinyl cords. In the results of high speed imaging system (HSIS) analysis, as soon as wire covering was damaged by heat, the conductor of wire came in contact with the other conduct of wire, and the short-circuit occurred. Stereomicroscope and SEM analysis indicated that the source part of wire showed V-type form. The molten beads of load part were bigger than those of source part. In the results of EDX analysis, Cu and O were detected in the source part, whereas covering material (Cl, Ca), Cu and O were detected in the load part. The results will help us to find out the cause of electrical fire.

• Journal of the Korean Society for Marine Environment & Energy
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• v.5 no.2
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• pp.35-40
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• 2002

By the introduction of cleaning and drying processes, thermal extrusion system for the volume reduction of used polystyrene buoys was developed. It was tested in the costal area for the determination of operational reliability. By the removal of oyster shells and cleaning of salt, waste polystyrene buoys was changed to the raw material of plastics. The lower cost of one-tenth compared with that of the outer request treatment is promising the practical use of waste buoys' volume reduction system.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2003.04a
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• pp.164-170
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• 2003

In this paper, we studied on the firing characteristics and electrical fire analysis of power cord deteriorated by thermal stress. The cross section of PVC insulating cord deteriorated by indirect flame decreased through heat convection. PVC insulating cord deteriorated by direct flame was bumpy shape. The exothermic peak of normal cord was shown at ($526.7^{\circ}C$), but the peaks or on(heat treatment temperature) ($150^{\circ}C$) cord was shown at ($299.6^{\circ}C$) and [$502.2^{\circ}C$]. The exothermic peaks according to high temperature were similar to those of amorphous carbon. In the FT-IR analysis, the absorption peak of normal cord indicated double bond of oxygen and carbon in benzene ring at 1720.0$cm^{1}$. As the HTT was high, the height of characteristic peak decreased and the peak of carbonyl group was shown at about 1625.7$cm^{-1}$. The characteristic peak of single bond(O-H) was shown at about 3479.2$cm^{-1}$. In case of the internal part of wire covering deteriorated by over current, the characteristic peak were shown at about 3417.3$cm^{-1}$ and 1600.2$cm^{-1}$. The above results show that we can distinguish the differences according to the fire pattern through the internalㆍexternal analysis of wire covering deteriorated by heat.

• Proceedings of the Korean Society for Emotion and Sensibility Conference
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• 1997.11a
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• pp.107-112
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• 1997

본 연구의 목적은 겨울철 난방시 한국인의 온열감각과 온열환경지표 사이의 상관관계 및 ASHRAE Standard 55-74의 쾌적영역과 한국인의 쾌적영역을 체감실험을 통해 규명 및 제시하는 것이다. 유니폼을 착용한 피실험자는 온도, 습도, 기류 등이 조절되는 환경시험실에서 2시간동안 체재하면서 매 15분 마다 전신온냉감, 쾌불쾌감 등을 신고하였다. 또한 인체의 3부위에서 피부온도, 환경시험실의 온도 및 습도를 매 20초 간격으로 측정하였다. 이상의 체감실험을 통해 아래의 결론을 얻었다. 1)평균피부온도가 증가함에 따라 TSV는 선형적으로 증가하며 열적으로 중립감을 느낄 때의 평균피부온도는 청년 34.$0^{\circ}C$, 고령자 33.5$^{\circ}C$이다. 2)TSV=0일때 청년의 중립 SET＊는 25.5$^{\circ}C$, 고령자의 중립 SET＊는 27.$0^{\circ}C$이다. 3)한국인의 쾌적범위는 청년의 경우 SET＊의 경우 24.2-26.8$^{\circ}C$, 고령자의 경우 SET＊25.7-28.2$^{\circ}C$로 ASHRAE St.55-74의 권장 쾌적범위 (22.0-25.4$^{\circ}C$)보다 다소 고온지향적이다.

• Journal of the Korean Association of Geographic Information Studies
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• v.15 no.2
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• pp.113-125
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• 2012

This research is aimed at evaluating the land surface characterization of KOMPSAT-3A middle infrared (MIR) data. Airborne Hyperspectral Scanner (AHS) data, which has MIR bands with high spatial resolution, were used to assess land surface temperature (LST) retrieval and classification accuracy of MIR bands. Firstly, LST values for daytime and nighttime, which were calculated with AHS thermal infrared (TIR) bands, were compared to digital number of AHS MIR bands. The determination coefficient of AHS band 68 (center wavelength $4.64{\mu}m$) was over 0.74, and was higher than other MIR bands. Secondly, The land cover maps were generated by unsupervised classification methods using the AHS MIR bands. Each class of land cover maps for daytime, such as water, trees, green grass, roads, roofs, was distinguished well. But some classes of land cover maps for nighttime, such as trees versus green grass, roads versus roofs, were not separated. The image classification using the difference images between daytime AHS MIR bands and nighttime AHS MIR bands were conducted to enhance the discrimination ability of land surface for AHS MIR imagery. The classification accuracy of the land cover map for zone 1 and zone 2 was 67.5%, 64.3%, respectively. It was improved by 10% compared to land cover map of daytime AHS MIR bands and night AHS MIR bands. Consequently, new algorithm based on land surface characteristics is required for temperature retrieval of high resolution MIR imagery, and the difference images between daytime and nighttime was considered to enhance the ability of land surface characterization using high resolution MIR data.

• Journal of the KSME
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• v.27 no.6
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• pp.504-514
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• 1987

복잡한 전자부품의 조립시에 필요한 열적 디자인에 관한 정보는 오래전부터 실험을 통하여 얻어지고 있다. 실험적 데이터를 이용하여 무차원 파라미터로 표시된 실험결과는 꼭 같지는 않지만 현상적으로는 비슷한 상황에 응용될 수 있다. 여기서는 학술문헌에 나타나 있는 자연대류에 관한 실험적인 상관관계식들과 프레임에 수직으로 꽂혀있는 균일가열 전자회로기판의 모델에서 얻어진 무차원 자료들을 비교하고자 한다. 대부분의 자료들은 수정채널 Rayleigh수(Ra")가 15~100범위에 속하며, 이러한 범위는 부품이 조밀하게 배치된 기관이 서로 좁은 채널을 이루고 있으며, 동시에 상당한 전력을 소비하고 있는 경우에 해당한다. Wirt와 Stutzman, Bar-Cohen과 Rohsenow의 일반상관관계식은 AT'||'&'||'T Bell 연구소에서 개발된 전자기기를 이용하여 수집한 실험데이터를 잘 표현하고 있으며 10 < Ra" <1,000범위에서 추천될 수 있다. 두개의 유사한 상관관계식과 비교할 때 상당히 좋은 예측을 보였으며 또한 Sparrow와 Gregg의 연구결과와도 잘 일치하므로 Ra" < 10인 경우에 Aung의 완전발달층류의 채널유동방식, Ra" > 1,000인 경우에는 Aung등의 단일 수직평판 근사식이 추천될 수 있다. Coyne의 알고리즘에 의한 계산치는 10

• Journal of the Korean Magnetics Society
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• v.7 no.5
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• pp.265-273
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• 1997

The MR ratios and the exchange biasing field and interlayer coupling field were investigated in $Ni_{91}Fe_{19}/Co_{90}Fe_{10}/Cu/Co_{90}Fe_{10}/NiO$ spin-valve sandwiches grown on antiferromagnetic NiO films as a function of the NiO thickness, the thickness of Cu and pinning layer $Co_{90}Fe_{10}$. The spin-valve sandwiches were deposited on the Corning glass 7059 by means of the 3-gun dc and 1-gun rf magnetron sputtering at a 5 mtorrpartial Ar pressure and room temperature. The deposition field was 50 Oe. The MR curve was measured by the four-terminal method with applied magnetic soft bilayer [NiFe/CoFe] (90$\AA$) decreased dramatically to less than 10 Oe when the NiFe/CoFe bilayer used an NiFe bilayer thicker that 20$\AA$. So NiFe layer improved the softmagnetic properties in the NiFe/CoFe bilayer. The GMR ratio and the magnetic field sensitivity of the spin-valve film $Ni_{91}Fe_{19}(40{\AA})/Co_{90}Fe_{10}(50{\AA}) /Cu(30{\AA})/Co_{90}Fe_{10}(35{\AA})/NiO(800{\AA})$ was 6.3% and about 0.5 (%/Oe), respectively. The MR ratio had 5.3% below an annealing temperature of 20$0^{\circ}C$ which slowly decreased to 3% above 30$0^{\circ}C$. The large blocking temperature of the spin-valve film was taken (as being) due to the good stability of the NiO films. Thus, the spin-valve films with a free NiFe/CoFe layer clearly had a high large GMR output and showed a effective magnetic field sensitivity for a suitable spin-valve head material.

• Journal of the Korean Association of Geographic Information Studies
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• v.24 no.1
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• pp.12-25
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• 2021

Land cover maps are used in various fields in urban expansion and development. This study analyzed the amount of land cover change over time using multi-sensor information, focusing on the waterfront area of the Taehwa River. In order to apply high-accuracy aerial hyperspectral images, patterns with Field-spectral were reviewed and compared with time series Digital map. The hyperspectral image was set as 13 land cover grades, and the time series digital map was classified into 7 and the waterfront area was classified into 5-6 grades and analyzed. As a result of analysis of the change in land cover of the digital map from the 1990s to 2010, it was found that forest areas were rapidly decreasing and Farmland and grassland were becoming urban. As for the land cover change(2010~2019) in the waterfront area(set 500m) analyzed through hyperspectral images, it was found that Farmland(1.4㎢), Forest(1.0㎢), and grassland (0.8㎢) were converted into urbanized and dried areas, and urbanization was accelerating around the Taehwa River waterfront. Recently, a lot of research has been conducted on the production of land cover maps using high-precision satellite images and aerial hyperspectral images, so it is expected that more detailed and precise land cover maps can be produced and utilized.

• Journal of the Korean Association of Geographic Information Studies
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• v.13 no.2
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• pp.107-118
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• 2010

The purpose of this study was to set the boundary of the coastal sand dunes and to analyze the change characteristics of land cover types using aerial photographs on Osan and Dongho coastal sand dunes in Yangyang. The boundaries of sand dunes were established using digital soil map, and land cover maps were made for each year using aerial photographs. As results of analysis, both beach and farmland areas have been decreased, since 1974 and forest area was relatively increased due to planting and forest growth. Facilities and bare land have been greatly increased since 1992. Loss of wetland, and beach due to these changes had an impact on the ecosystem destruction of sand dunes.