• 한국정보처리학회:학술대회논문집
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• 한국정보처리학회 2003년도 춘계학술발표논문집 (상)
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• pp.679-682
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• 2003

카타디옵트릭 카메라는 거울을 이용하여 $360^{\circ}$의 3차원 이미지를 한 장에 촬영할 수 있는 이미지 시스템이다. 본 논문에서는 이 시스템을 사용할 때에 발생하는 이미지 왜곡 문제를 해결하는 구형투영 알고리즘을 제안한다. 흔히 사용하는 실린더형 알고리즘의 경우 계산은 비교적 간단하지만, 거울의 바로 아래에 있는 물체의 경우 전체적인 영상을 볼 수 없다는 단점이 있다. 본 연구에서 사용한 카메라는 포물면 거울을 사용한 카타디옵트릭 카메라이며, 쌍곡면거울을 사용한 카메라에 대해서도 이론적으로 공식을 유도하였다.

• 한국안전학회지
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• 제12권2호
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• pp.87-94
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• 1997

If sodium azide is impinged by certain reasons, it will be produced explosives by heavy metals and toxic materials. But it is used propellent for inflating automotive safety bags and the other chemical manufacturing purpose. The investigation of thermal hazard potential of sodium azide itself and with polymers ate very important because some parts of automotives, transporting vessels of reactive chemicals and many any other constituents of structures in factories are made of polymers. The range of decomposition temperatures are about $360-380^{\circ}C$, even if it depends on heating rate and sample weight. Thermal decomposition heat of sodium azide in air is higher than in nitrogen atmosphere, because the former is included oxidizing heats of sodium metal which is made by decomposition of sodium azide to end. Especially decomposition temperature of polymers are increased on the order of bonding energy between atoms in hydrocarbon moleculars.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2005년도 하계학술대회 논문집 Vol.6
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• pp.359-360
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• 2005

PZT(20/80) and PZT(80/20) powders, prepared by the sol-gel method, were mixed with an organic vehicle and the PZT(20/80)/PZT(80/20) heterolayered thick films were fabricated by the screen-printing method on Pt/$Al_2O_3$ substrates. The structural properties such as DTA, X-ray diffraction and microstructure, were examined as a amount of the excess PbO. In the DTA analysis, the formation of the polycrystalline perovskite phase was observed at around $880^{\circ}C$. The average thickness of the PZT heterolayered thick films was approximately $80{\mu}m$.

• Macromolecular Research
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• 제16권4호
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• pp.360-366
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• 2008

Poly(dialkoxyphenylene 1,3,4-oxadiazole)s were conveniently synthesized to compare their material properties of solvent solubility, thermal stability and molecular alignment with respect to alkyl chain length and meta/para-phenylene structure. All prepared polymers exhibited good solubility in co-solvents containing various volume levels of chloroform to trifluoroacetic acid. Meta-polymers showed slightly better solubility than para-polymers. All polymers produced were thermally stable up to $320^{\circ}C$. Photoluminescence of polymer films was observed with blue light emission at around 450 nm. X-ray diffraction patterns of all polymers indicated that they were composed of stacked molecular sheets with the same layer-to-layer distance of $3.4\;{\AA}$. However, side chain-to-side chain and main chain-to-main distances within the layers increased with increasing alkyl chain lengths. The meta-polymer chains were separated more than the para-polymer chains.

• 한국염색가공학회지
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• 제12권6호
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• pp.353-360
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• 2000

In this article, arrowroot is extracted in distilled water, and its dyeing properties on wool, nylon, and silk were investigated. Also the effect of mordanting (Al, Cu, Sn, Fe and Cr compounds) on the wash fastness are measured. The wavelength of maximum absorption of the arrowroot extract appears at 250 and 300nm below pH 7, but they shifted to longer wavelength at higher pH values. It appears that the optimum condition of the dyeing of wool, nylon, and silk fabric with arrowroot extract is $60^\circ{C}$, 60 min, and pH 4.0. Mordant treatments are effective in improving wash fastness of polyamide fabrics.

• 한국표면공학회지
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• 제52권5호
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• pp.275-281
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• 2019

Anodization is widely used to enhance the properties of aluminum, such as hardness, electric resistance, abrasion resistance, corrosion resistance etc. But these properties can be enhanced with additional process. According to the partial crystallization of oxide layer with post heat treatment, enhanced hardness can be expected with partial crystallization. In this study, post heat treatments were applied to the anodized aluminum alloys of Al6061 to achieve the partial crystallization, and crystallizations were evaluated with the reduced breakdown voltages. Interestingly, remarkable enhanced hardness (21~29%), abrasion resistance (26~62%), and reduced breakdown voltage (24~44%) were observed for the sulfuric acid anodized samples when we annealed the anodized samples with 1hour post heat treatment at $360^{\circ}C$. For the Al5052 alloys, a lot of cracks were observed when we applied the post heat treatment.

• 한국자기학회지
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• 제5권5호
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• pp.623-626
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• 1995

High coercivity thin $Fe_{3}O_{4}$ and ${\gamma}-Fe_{2}O_{3}$ films were deposited on Si substrate under well controlled $O_{2}$ partial pressure by dcreactive magnetron sputtering. The coercivity of as-deposited maggnetite films is below 640 Oe. After cxidizing at $360^{\circ}C$ for 10 minutes, the films transform to maghemite ${\gamma}-Fe_{2}O_{3}$ completely, and the coercivity increases greatly to 2100~4120 Oe, depending on modification of not with minor addition of Co or/and Mn. The orign of coercivity enhancement is attributed mainly to magnetic anisotropy arisen from interfacial stress. The addition of 5 at% Co and 5 at% Mn greatly enhances coercivity and squareness ratio. These films are potential for ultra-high density recording applications.

• 한국산업융합학회 논문집
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• 제21권6호
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• pp.355-360
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• 2018

The product developed in this study is a ceramic catalyst filter for 1 ton heavy-oil boiler that can simultaneously process dust and nitrogen oxides. This has been developed for simultaneous processing of nitrogen oxides and dust at high efficiency of hot exhaust gas (approximately $300^{\circ}C$) generated after burning 1 ton heavy oil boiler. Ceramic catalytic filters for 1 tonne heavy-duty glass display are technologies that remove 90% of dust and 85% or more of nitrogen oxides. This is an improved new technology to integrate exhaust ventilation and desiccation devices into one, thereby reducing the production process and improving the economy. To this end, the performance test of the catalytic filter for heavy oil boilers was carried out, and the durability of the PLC circuit was constructed.

• 한국표면공학회지
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• 제32권3호
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• pp.360-362
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• 1999

Formation of the nickel-cadmium alloy in the negative electrode of nickel-cadmium cell subjected to continuous charging at elevated temperatures ($40~45^{\circ}C$) is shown to be one of the causes of the 'stepped' discharge curves. The alloy has been characterized by electrode potential measurement and X-ray diffraction method. The potential lowering during discharge is related to discharge of the alloy. X -ray diffraction suggests that the nickel-cadmium alloy can be formed during charge in negative electrode by interaction of the two metals. Addition of Ni $(OH)_2$ into $Cd{\;}(OH)_2$ active material is found to form the alloy more readily than sintered negative electrode alone.ode alone.

• 대한원격탐사학회지
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• 제33권5_1호
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• pp.559-570
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• 2017

본 연구에서는 야외에서 자료 취득이 가능하며 한 번에 다량의 사과를 촬영할 수 있는 지상용 초분광 스캐너를 활용하여 사과의 분광정보와 당도와의 부분최소제곱회귀분석(PLSR, Partial Least Square Regression)을 수행하였으며, 최적의 예측모델을 구축하기 위한 다양한 전처리기법의 적용가능성을 평가하고 VIP(Variable Importance in Projection)점수를 통한 최적밴드를 산출하였다. 이를 위하여 360-1019 nm영역에서 촬영된 515밴드의 초분광 영상에서 70개의 분광곡선을 취득하였으며, 디지털광도계를 이용하여 당도($^{\circ}Brix$)를 측정하였다. 사과의 분광특성과 당도사이의 회귀모델을 구축하였으며, 최적의 예측모델은 모델 예측치와 실측치간의 결정계수($r_p^2$, coefficient of determination of prediction)와 RMSECV(Root Mean Square Error of Cross Validation), RMSEP(Root Mean Square Error of Prediction)등을 고려하여 선정하였다. 그 결과 산란보정 기법의 대표적인 MSC(Multiplicative Scatter Correction)의 기반의 전처리기법이 가장 효과적이었으며, MSC와 SNV(Standard Normal Variate)를 조합한 경우 RMSECV와 RMSEP가 각각 0.8551과 0.8561로 가장 낮았고, $r_c^2$와 $r_p^2$은 각각 0.8533과 0.6546으로 가장 높았다, 또한 360-380, 546-690, 760, 915, 931-939, 942, 953, 971, 978, 981, 988, 992-1019 nm 등이 당도 측정을 위한 가장 영향력 있는 파장영역으로 나타났다. 해당 영역의 분광값을 가지고 PLSR을 수행한 결과, 전파장대를 사용할 때보다 RMSEP가 0.6841로 감소하고 $r_p^2$는 0.7795로 증가하는 것을 확인하였다. 본 연구를 통하여 사과의 당도측정에 있어 야외에서 취득한 초분광 영상자료의 활용 가능성을 확인하였으며, 이는 필드자료 및 센서 활용분야의 확장가능성을 보여준다.