• Journal of the Korean Ceramic Society
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• v.36 no.1
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• pp.55-60
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• 1999

${\beta}$-SiC thin film was deposited on a Si substrate without buffer layer using a single precursor of Hexamethyldisilane (Si2(CH3)6) by chemical vapor deposition method. HCI gas was introduced into hexamethyldisilane /H2 gas mixture, and the feeding schedule of HCI and precursor gases was modified in order to enhance the selectivity of SiC deposition between a Si substrate and a SiO2 mask. The effect of HCI gas on the surface roughness of the SiC film was investigated and typical electrical properties of the SiC film were also investigated by Hall measurement.

• Journal of the Korean Solar Energy Society
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• v.29 no.1
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• pp.11-17
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• 2009

Daylighting is core of sustainable design in most buildings. Well-designed daylighting systems can significantly reduce or even eliminate the electric lighting loads during the day time, including air conditioning energy loads. Among window systems. the topside lights systems including monitor lighting, sawtooth lighting, sunscoop and, lightscoop is one of the most popular apparatus to improve the lighting quantity. Also they are important both in terms of energy savings and visual quality. The objective of this study is to analyse daylighting performance of topside lighting system for different orientations. Four types of topside lighting system were tested and comparpd: monitor lighting, sawtooth lighting, lightscoop and sunscoop. Totally 25 measuring points of illuminance on the horizontal plane were monitored from 09:00 to 17:00 on October 6, 2008. Agilent data logger and photometric sensors Li-cor were used. Comparisons with a light factor is discussed. The results found in this study would mean that there were no significant differences in light factor between three cases.

• Proceedings of the Korea Water Resources Association Conference
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• 2010.05a
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• pp.1481-1485
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• 2010

강원지역은 산지가 89%를 차지하고 있어 도로의 대부분이 하천을 끼고 발달되어 있어서 집중호우 시 하천 만곡 수충부에서 급격한 홍수위 상승과 하상세굴이 발생되고 산지의 수로나 계곡 등에서 토석류가 발생되기 때문에 극심한 도로피해가 빈발하고 있다. 산지하천은 지형 및 지질적인 요인으로 경사가 급한 만곡 수충부가 많이 발달되어 있기 때문에 홍수시 유속이 매우 빠르고 만곡 수충부에서 수위상승과 횡방향 수위변동이 심하다. 따라서 산지유역의 하천과 도로의 방재설계를 위해 평창 속사천 시험유역의 운영을 통하여 신뢰성 있는 고품질의 산간유역 수문자료를 지속적으로 확보하고자 한다. 강우-유출구조 규명을 위한 강우관측소와 수위관측소 등의 계측시스템을 설치와 실시간 수문관측 자료의 전송 및 정기적인 현장 방문으로 수집된 수리수문자료에 대해 DB를 구축을 실시하였다. 또한 홍수시 하천으로 유입되는 토석류의 조도계수 산정을 통해 하천유역내의 수리 구조물의 설계 및 유지관리, 하천개수 및 하도의 안정 등을 평가할 수 있을 것이다. 하천계획에 필요한 유사량을 측정하여 유역의 수문.수리특성에 대한 보다 정확한 규명과 관측된 자료를 이용한 장/단기 수문순환 및 수리모형의 개발을 위한 검정 및 검증자료의 제공할 것으로 기대된다.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2006.05a
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• pp.114-119
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• 2006

운전자의 시인성, 뇌파, 심리평가를 위한 실내 실험실 및 측정 시스템을 구축하고 예비실험 결과를 분석한 후 운전자의 시인성을 측정하였다. 본 실험을 위하여 남, 녀 각각 20명의 피험자를 선발하였으며 이들의 연령은 피험자의 연령에 의한 측정오차를 최소화하기 위하여 모두 20대로 제한하였다. 그리고 본 실험 측정결과를 전압패턴에 따라 피험자의 장애물 인식 반응속도를 분석하였고, 남-녀 성별 간의 장애물 인식 반응속도 차이를 분석하였다. 또한 전조등의 전압변동에 의한 밝기 비율에 따라서 피험자의 장애물 인식 반응속도를 분석하였고, 전압변동이 없을 때의 장애물 인식 반응속도를 기준으로 상대적인 장애물 인식 지연시간을 분석하였다.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.7 no.6
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• pp.1243-1248
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• 2006

Object tracking in a real time image is one of interesting subjects in computer vision and many practical application fields past couple of years. But sometimes existing systems cannot find object by recognize background noise as object. This paper proposes a method of object detection and tracking using adaptive background image in real time. To detect object which does not influenced by illumination and remove noise in background image, this system generates adaptive background image by real time background image updating. This system detects object using the difference between background image and input image from camera. After setting up MBR(minimum bounding rectangle) using the internal point of detected object, the system tracks object through this MBR. In addition, this paper evaluates the test result about performance of proposed method as compared with existing tracking algorithm.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2011.04a
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• pp.425-429
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• 2011

The development of metal plasma generated by high laser irradiance and its effect on the surrounding air using shadowgraph images after laser pulse termination are studied; hence the formation of laser supported detonation and combustion processes has been investigated. The core of the paper is in detecting chemical reaction using X-Ray Diffraction (XRD) between ablated aluminum plasma and oxygen from air by inducing high power laser pulse (>1000 mJ/pulse) and conduct a quantitative comparison of chemically reactive laser initiated waves with the classical detonation of exploding aluminum (dust) cloud in air. This study may suggest a new approach of initiating detonation from metal sample in its bulk form without the need of mixing nano-particles with oxygen for initiation.

• Journal of Platform Technology
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• v.10 no.4
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• pp.82-90
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• 2022

emerging. And it shows numerous possibilities and tremendous potentials in the virtual world. This metaverse is not limited to one type, but it is evolving and developing into a service in the form of a virtual convergence economy by breaking down boundaries. As a result, various security issues in metaverse are emerging. Metaverse performs all activities in the virtual space, so various problems such as privacy infringement, virtual asset theft, or fraud can occur. In this paper, a service security model is proposed to provide safe services on metaverse. To this end, we analyze security threats in the metaverse framework and propose a security service model to prevent threats. By evaluating the security of the proposed model, it was shown that safe services are effectively possible on the metaverse.

• Proceedings of the Korea Water Resources Association Conference
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• 2022.05a
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• pp.167-167
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• 2022

최근 빅데이터에 관련된 연구에 있어 데이터의 품질관리에 대한 논의가 꾸준히 이뤄져 오고 있다. 특히 이미지 처리 및 분석에 활용되어온 딥러닝 기술의 경우, 분류 작업 및 패턴인식 등으로부터 데이터의 특징을 추출함으로써 비지도학습(Unsupervised Learning)을 가능하게 한다는 장점이 있음에도 불구하고 빅데이터를 다루는 과정에 있어 용량, 다양성, 속도 및 신뢰성 측면에서의 한계가 있었다. 본 연구에서는 CCTV 영상을 활용한 강수량 산정 모델 개발에 있어 예측 정확도 향상 및 성능 개선을 도모할 수 있는 데이터 전처리 방법을 제안하였다. 서울 근린 AWS 4개소 지역(김포장기, 하남덕풍, 강동, 성남) 및 중앙대학교 지점 내 CCTV를 설치한 후, 최대 9개월의 영상을 확보하여 강수량 산정을 위한 딥러닝 모델을 개발하였다. 배경분리, 조도조정, 영역설정, 데이터증진, 이상데이터 분류 등이 가능한 알고리즘을 개발함으로써 데이터셋 자체에 대한 전처리 작업을 수행한 후, 이에 대한 결과를 기존 관측자료와 비교·분석하였다. 본 연구에서 제안한 전처리 방법들을 적용한 결과, 강수량 산정 모델의 예측 정확도를 평가하는 지표로 선정한 평균 제곱근 편차(Root Mean Square Error; RMSE)가 약 30% 감소함을 확인하였다. 본 연구의 결과로부터 CCTV 영상 데이터를 활용한 강수량 산정의 가능성을 확인할 수 있었으며 특히, 딥러닝 모델 개발시 필요한 적정 전처리 방법들에 대한 기준을 제시할 수 있을 것으로 판단된다.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2022.11a
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• pp.147-148
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• 2022

Due to recent climate abnormalities, the form of rainfall is changing to localized torrential rains. Localized torrential rains cause flooding in urban areas. In addition, in various industrial fields, there are cases where materials necessary for the process are kept outdoors, and damage from material loss and flooding of stockyards occurs during heavy rain. Accordingly, it is necessary to introduce a drainage layer where flooding is expected. This drainage layer places the aggregate inside and allows rainwater to penetrate and drain into the voids between the aggregates. However, the amount of voids differs according to the particle size distribution and particle size of the aggregate, and the drainage performance varies according to the compositional location of the aggregate. Therefore, in this study, the drainage characteristics according to the particle size, particle size, and compositional location of aggregates are analyzed using a fluid analysis program.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.37 no.3
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• pp.629-636
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• 2017

Urban railway are the most widely used means of transportation in the metropolitan area. It is difficult to draw out problems through the quantitative analysis technique because most of the research results show that most of the guide signs are installed with many or few guide signs. In this study, we propose a method to evaluate the information load and proper installation location at the main decision point in the transfer passageway for Suseo Station by applying Positive Guidance. As a result of analyzing the information load using this technique, it is suggested that the necessary information should be provided centered on the copper node because it provides confusion of the users by providing the same information in the transfer line. It is necessary to obtain guidance on how to remove the sign (advertising, high ceilings, etc). The study will be regarded as a key for the basis and placement of the guidelines for determining the appropriateness of the in the future urban railway station sign guide.