• Journal of the Society of Naval Architects of Korea
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• v.45 no.6
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• pp.601-610
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• 2008

This paper deals with a new geometrical surface modeling method of forebody's hull form which is fully defined by form parameters. The complex hull form in the forebody can be modeled by the combination of three parts: bare hull, bulbous bow and blending part which connects a bare hull and a bulbous bow. All these subdomain parts are characterized by each own form parameters and constructed with simple surface model. For this, we need only 2-dimensional hull form data and then the form parameters are calculated automatically from these data. Finally, the smooth hull form surfaces are generated by parametric design and fair-skinning. In the practical point of view, we show that this new method can be useful and efficient modeling tool by applying to the hull form surface modeling of Panamax container's forebody.

• Bulletin of the Korean Chemical Society
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• v.33 no.4
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• pp.1177-1182
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• 2012

The corrosion resistance of 316L stainless steel coated with NiO-YSZ (Ni added yttria stabilized zirconia) was examined in a proton exchange membrane fuel cell (PEMFC) environment. The NiO-YSZ coating was carried out using a sol-gel dip coating method, and the corrosion resistance and interfacial contact resistance (ICR) were determined by the composition and morphology of the NiO-YSZ film. The corrosion resistance increased with increasing Ni content in the NiO-YSZ film, but rapid corrosion was observed when the YSZ film contained more than 15 wt % Ni due to surface cracks. The polarization resistance was improved by several orders of magnitude when 316L stainless steel was coated with a 15 wt % NiO-YSZ film compared to bare 316L. The ICR of the NiO-YSZ film was decreased to that of bare 316L when the YSZ film contained 25 wt % NiO, suggesting the possible application of NiO-YSZ coated stainless steel for a bipolar plate.

• Corrosion Science and Technology
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• v.5 no.3
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• pp.106-111
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• 2006

Painting has protected metallic stack but the paint films may be degraded and corrosion problem can be arisen. To protect the painted metal stack, cathodic protection can be applied. If cathodic protection is applied to bare metal, only small area may be protected. However, if cathodic protection is applied to painted metal surface, large area can be protected and the lifetime of paint films can be extended. High corrosion resistant alloys were corroded at a Flue Gas Desulfurization (FGD) facility of power plant within a short period and thus cathodic protection can be used to protect these metals. On the base of computer simulation, if cathodic protection is applied to bare metal in a FGD environment, it was estimated that applied current could almost be spent to protect area near the anode. However, if cathodic protection is applied to high resistant-coated metal, the much larger area from the anode could be effectively protected.

• Proceedings of the KIEE Conference
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• 2005.07c
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• pp.2094-2096
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• 2005

In this paper, we studied the cross section analysis based on the short circuit conditions of the low voltage bare wires. The copper wires prepared for the experiment were 1.2mm 1.6mm and 2.0mm in diameter. Through the cross section analysis(CSA), it was confirmed that the dendrite structure grew at the angle of about $40^{\circ}$ or $60^{\circ}$ when the fusing current was applied to the wires. The larger the fusing current is, the more decreased the growth angle of the dendrite structure is. It was confirmed that the dendrite structure was arranged like the columnar structure. In this paper, the characteristics analysis of short circuit was carried out in the range of transient duration.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.1538-1539
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• 2007

모세관 전기 영동법을 이용한 전기화학적 검출기로 환경호르몬을 분리, 검출하는 연구를 수행하였으며 여러 가지 전극들간의 감도를 포함한 경제성과 효율을 비교하였다. 검출기에 사용된 전극으로는 Indium Tin Oxide (ITO) 전극과 bare ITO 전극 위에 Prussian blue (PB) 용액을 전착한 전극이 사용되고 검출기는 3전극을 사용하는 형식으로 제작하였다. PB전극이 사용된 검출기를 이용하여 비스페놀 A를 측정한 결과, bare ITO 전극을 사용한 검출기보다 우수한 민감도를 얻었다.

• Korean Journal of Remote Sensing
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• v.17 no.2
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• pp.141-153
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• 2001

A semi-empirical polarimetric backscattering model for bare soil surfaces is presented. Based on measurements by using polarimetric scatterometers and the JPL AirSAR, as well as the theoretical models, the backscattering coefficints $\sigma$$^0_w$, $\sigma$$^0_{hh}$ and $\sigma$$^0_{vh}$, and the parameters of the copolarized phase-difference probability density function, namely the degree of correlation $\alpha$ and the copolarized-phase-difference $\zeta$, are modeled empirically in terms of the volumetric soil moisture content m$_v$ and the surface roughness parameters $k_s$ and $k_l$, where k=2$\pi$f/c, s is the rms height and l is the correlation length.

• International Journal of Naval Architecture and Ocean Engineering
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• v.7 no.3
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• pp.466-477
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• 2015

In this study, a numerical prediction method on manoeuvrability of Wind Turbine Installation Vessel (WTIV) is presented. Planar Motion Mechanism (PMM) captive test for the bare hull of WTIV is carried out in the model basin and compared with the numerical results using RANS simulation based on Open-source Field Operation And Manipulation (OpenFOAM) calculation to validate the developed method. The manoeuvrability of WTIV with skeg and/or without skeg is investigated using the numerical approach along with the captive model test. In the numerical calculations, the dynamic stability index which indicates the course keeping ability is evaluated and compared for three different hull configurations i.e. bare hull and other two hulls with center skeg and twin skeg. This paper proves that the numerical approach using RANS simulation can be readily applied to estimate the manoeuvrability of WTIV at the initial design stage.

• Proceedings of the Korea Information Processing Society Conference
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• 2012.04a
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• pp.753-755
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• 2012

최근 클라우드 서비스의 가상화 기술이 급부상 하면서 이슈화되고 있는 문제는 안전성과 신뢰성이다. 클라우드 서비스의 가상화 계층의 손상은 모든 호스트 업무의 손상을 가져올 수 있기 때문에 복수의 가상 운영체제가 구동될 수 있는 환경을 제공하는 하이퍼바이저는 해커들에 의해 공격 대상이 될 수 있다. 본 논문에서는 클라우드 서비스를 위한 대표적인 기술 중 보안이 취약하다고 분석되는 베어 메탈 기반의 하이퍼바이저의 해킹 및 악성코드에 대한 차단 기법을 제안한다.

• Journal of the Korean Physical Society
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• v.73 no.11
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• pp.1725-1728
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• 2018

We synthesized the gold nanoparticles (Au NPs)-embedded methylammonium lead iodide ($MAPbI_3$) film for the first time. The effects of metal nanoparticles on $MAPbI_3$ perovskite were systematically studied using UV-Vis absorption and photoluminescence (PL) measurements. As a result, the 20-nm-sized Au NPs-embedded $MAPbI_3$ film exhibited a 4.15% higher absorbance than the bare $MAPbI_3$ film. Moreover, the average PL intensity of the Au NPs-embedded $MAPbI_3$ film increased by about 75.25% over the bare $MAPbI_3$ film. Therefore, we have confirmed that addition of the Au NPs has a positive effect on the optical properties of $MAPbI_3$, and we believe that this study will provide a basic insight into the metal nanoparticles-embedded perovskite thin films for the future optoelectronic applications.

• Animal Systematics, Evolution and Diversity
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• v.37 no.1
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• pp.64-69
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• 2021

The genus Krenosmittia is a small group of Orthocladiinae, containing a total of twenty species in the world. Among them, six species were found in Japan, four species in China, and five species from the Russian Far East. This genus can be distinguished from other Orthocladiinae genera by the eyes bare, absence of acrostichals on thorax, costa strongly extended, anal vein ending proximal to FCu, squama bare, and having a strongly developed virga. We report three new species: K. danyangensis n. sp., K. triangulia n. sp., and K. pseudoannulata. The genus Krenosmittia is the first record in Korea. Line drawings of the diagnostic characters are provided for all the species recognized in this study.