• Rapid Communication in Photoscience
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• v.4 no.1
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• pp.19-21
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• 2015

Zeolite is an ideal host material for encapsulating nano-size metal catalyst species because of its defined microporous structure, prominent adsorption/condensation properties, high surface area, chemical/thermal stability, and transparency to light. In this study, $TiO_2$ photocatalyst was incorporated in highly hydrophobic Y zeolite and its photocatalytic activity was examined in the photocatalytic oxidation of olefins under UV-light irradiation using molecular oxygen as an oxygen source. $TiO_2$ nanoparticles incorporated in hydrophobic Y zeolite exhibited a markedly enhanced photocatalytic activity compared with bare $TiO_2$ owing to its excellent affinity toward organic moieties, which facilitates the mass transfer of organic substrates and allows them to efficiently access to the neighboring active $TiO_2$ surface.

• Progress in Superconductivity
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• v.4 no.1
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• pp.59-63
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• 2002

10-V Josephson junction array arranged in 8 parallel stripline paths was fabricated using self-aligning and reactive ion etching techniques. These techniques were introduced in detail with aim of obtaining high-quality junctions. The array has 18,184 Josephson junctions with the area of $12\mu\textrm{m}$$\times$$38\mu\textrm{m}$. The gap voltage and minimum critical current density were about 2.7 ㎷ and ／$23 A\textrm{cm}^2$, respectively. And the critical current density and leakage current at 5 volt were about 27 $A／\textrm{cm}^2$ and $5\mu\textrm{A}$, respectively When operated in the frequency range of 76-88 ㎓, the away generated constant voltage steps up to 14-19 V. The step size near 10-V was more than 7 $\mu\textrm{A}$.

• Progress in Superconductivity
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• v.4 no.1
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• pp.64-67
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• 2002

The attenuation of millimeter waves (70-100 ㎓) propagating along Josephson Junction stripline had been measured by pattern recognition near gap voltage and proximity current bump. Test series arrays of 2000, 3000, and 4000 Josephson junctions with the area of $12\mu\textrm{m}$$\times$ $38\mu\textrm{m}$ had two sub-arrays with 50 Junctions at both ends. The arrays were fabricated with and without applying a plasma nitridation process to Nb ground plane. The effects of a nitridationprocess measured by the pattern recognition near gap voltage and proximity current bump were about 1.3-1.7 ㏈ and 1.6-1.8 ㏈, respectively. This means that the last sub-arrays with a nitridation process receive 26-34% more power than those without a nitridation process.

• Journal of the Korean Society for Nondestructive Testing
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• v.21 no.4
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• pp.383-390
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• 2001

Long-range guided wave inspection is a new emerging technology for rapidly and globally inspecting a large area of a structure from a single test location. This paper describes a general overview of the guided wave properties and its application for long-range inspection of structures the principle and instrument system for a guided wave inspection technology called "magnetostrictive sensor (MsS)" that generates and detects guided waves electromagnetically in the material under testing, and examples of long-range guided wave inspection of structures that can be accomplished using the MsS.

• Hwankyungkyoyuk
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• v.13 no.2
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• pp.1-13
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• 2000

The purpose of this study is to investigate the present status of environmental education administration in the middle schools of Seoul City and to find problems to be solved environmental education in middle schools. To accomplish these purpose surveys for middle school teachers in Seoul was conducted, and evaluation reports of school environmental education of 1998 were analyzed. The results indicated that both schools and Ministry of Education offered few evaluation standards related to environmental education. Most schools abolished division of environmental affairs because of the reorganization of school system, which focuses on subject and aptitude-based education. In addition, environmental education and related activities were maily the responsibilities of division of science education. The teachers responded that such activities as organization and management of mothers'social service, management of environment day, use of environmental conservation card, and establishment of conservation area were not effective and should be abolished. The conclusion from this study are that environmental education can be effective only when goals of environmental education are included in school evaluation, and the division of environmental affairs should be revived and systematically operated in school.

• 한국지구물리탐사학회:학술대회논문집
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• 2007.06a
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• pp.349-352
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• 2007

Estimating the physical properties of the survey area and mapping the geotechnical basement play an important role in ocean engineering and construction field. In this study, we performed marine seismic reflection and refraction survey as an engineering application at shallow marine. We made use of the dual boomer - single channel streamer as a source-receiver in reflection seismic survey and air-gun source - the manufactured OBC(Ocean Bottom Cable)-type streamer in refraction survey. In the seismic reflection data, we could easily find the geological layers and basement. Moreover, seismic refraction data could present sediment thickness and velocity distribution.

• Proceedings of the IEEK Conference
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• 2006.06a
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• pp.201-202
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• 2006

In this paper, we achieved software and hardware implementation of SHA-1 hash function for sensor network. We implemented the software to be compatible with TinySec. In hardware design, we optimized operation logics for small area of hardware and minimized data transitions of register memory for low power design. Designed the software and hardware is verified on commercial sensor motes and our secure motes respectively.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2004.11a
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• pp.137-142
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• 2004

There has been considerable controversy over the change of coastal topography and shoreline by coastal erosion in Gohyun Bay, Geojedo. In this study, we analyzed aerial photographs and surveyed coastal topography and shoreline. Changes between years were identified using a GIS overlay analysis and field surveys with DGPS, Total Station and Echo Sounder. As a result, we were able to identify changes by coastal erosion in the area of Gohyun Bay, Geojedo.

• ETRI Journal
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• v.28 no.3
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• pp.367-370
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• 2006

This letter presents a multi-modal approach to tracking geographic objects such as buildings and road signs in a video sequence recorded from a moving vehicle. In the proposed approach, photogrammetric techniques are successfully combined with conventional tracking methods. More specifically, photogrammetry combined with positioning technologies is used to obtain 3-D coordinates of chosen geographic objects, providing a search area for conventional feature trackers. In addition, we present an adaptive window decision scheme based on the distance between chosen objects and a moving vehicle. Experimental results are provided to show the robustness of the proposed approach.

• Proceedings of KOSOMES biannual meeting
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• 2005.05a
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• pp.175-177
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• 2005

본 연구는 도서지방에 식수를 안정적으로 공급하기 위하여 도서별 특성에 적합한 최적의 상수원 방안을 마련하는데 목적이 있다. 특히 도서지역은 지형적인 특정상 상수원 확보를 위한 저수지 건설의 적지가 드물고 이상 가뭄과 환경오염으로 물 부족 현상이 심화되고 있으므로 도서지방의 안정적인 식수 공급 방안 수립은 시급한 실정이다.