• The Journal of Korean Institute of Communications and Information Sciences
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• v.28 no.8A
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• pp.644-649
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• 2003

Novel 622Mb/s burst-mode clock and data recovery (CDR) circuits with muxed oscillators are realized for passive optical network (PON) application. The CDR circuits are implemented with 0.35$\mu\textrm{m}$ CMOS process technology. Lock is accomplished on the first data transition and data are sampled in the optimal point. The experimental results show that the proposed CDR circuits recover the incoming 400Mbps-680Mbps burst mode input data without error.

• Proceedings of the Korea Water Resources Association Conference
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• 2011.05a
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• pp.141-141
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• 2011

생태적 기능이 담보되는 하안의 조성 및 복원은 필연적으로 하안공간에서 물리적 구조변화를 야기한다. 이러한 하안공간의 물리적 구조변화는 장기적으로 구간에서의 생태적 기능뿐만 아니라 단기적으로 하천의 수리특성변화를 야기한다. 이러한 수리특성변화는 복원구간에서의 생태적 기능에 직접적인 영향을 준다. 하천복잡도에 따른 수리특성의 변화는 자연형 하천복원에 영향을 주는 변수이므로 이들 변화를 예측할 수 있는 하천복잡도 시나리오의 수립은 매우 중요하다. 따라서 본 연구에서는 2차원 하상변동 수치모형인 CCHE2D 모형을 이용하여 하천유형에 따른 수리특성을 분석하고자 하였다. 하천복잡도 시나리오는 Rosgen (1994)에 의해 제안된 하천분류방법과 유량크기별 모의 시나리오를 작성하여 모델에 적용하였다. 연구대상지역은 안성천유역의 오산천과 진위천으로 하천분류결과 크게 C유형과 E 유형으로 분류되었다. 분류된 유형의 수리특성 분석을 위해 C 유형의 구간중 진위천 본류구간과 통삼천의 만곡구간을 선정하여 모형을 구동하였다. 모형의 입력자료인 유한요소망은 하천정비기본계획의 부도를 이용하여 생성하였으며 모델의 경계입력자료는 WMS HEC-1의 유출량 결과 자료를 사용하였다. 빈도별 강우량 자료를 Huff의 4분위 법을 적용하여 24시간으로 분포화하여 빈도별, 구간별 유출량 자료를 구축하여 모의 하였다. 선정한 하천유형구간에 대하여 유량크기별 수위, 유속, 한계유속, 소류력에 대한 흐름특성분석을 실시하였으며, 조도계수의 변화에 따른 흐름특성 변화를 분석하였다.

• Korean Journal of Food Science and Technology
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• v.35 no.2
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• pp.254-259
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• 2003

Effects of freeze-drying on microbiological and sensory characteristics of yulmoo-kimchi (leaf radish kimchi) were investigated. Freeze-dried yulmoo-kimchi was stored at 0, 10 or $25^{\circ}C$ for 60 days and rehydrated with water. Optimum rehydration time of freeze-dried yulmoo-kimchi was 2 hr. Number of lactic acid bacteria of freeze-dried, 10 days-stored, rehydrated yulmoo-kimchi decreased significantly (p<0.05) in comparison with that of reference sample (non-freeze-dried yulmoo-kimchi), while no significant changes were observed after 10 days. As storage temperature increased, number of lactic acid bacteria of 10 days-stored samples decreased. pH value slightly increased by freeze-drying, while it decreased gradually during 60 days of storage. Sensory properties of freeze-dried/rehydrated sample were slightly inferior to those of reference sample, but those were relatively good when the sample was evaluated solely. Overall acceptability of freeze-dried, $0^{\circ}C$-stored, rehydrated sample was significantly inferior to reference sample (p<0.05) and it gradually decreased as storage temperature increased. Between storage periods of 10 through 60 days, sensory properties of 0 and $10^{\circ}C$-stored sample slightly decreased, while those of $25^{\circ}C$-stored sample decreased markedly.

• Journal of Conservation Science
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• v.35 no.3
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• pp.197-208
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• 2019

Biological damages of wooden cultural properties are closely related to the preservation of the environment; these damages can be accelerated because of rapid climate change. Therefore, to preserve cultural properties, it is important to understand environmental characteristics. This study aims to investigate the status of termite damage and the characteristics of major environmental factors such as micro-meteorology, meso-meteorology, and local-meteorology of the Josadang shrine in the Seonamsa temple at Suncheon. Damage was confirmed by visual observation and the response of the termite detection dog at the north-west corner. Also another damage was observed by the termite detection dog at the north-east corner. These pillars had lower surface temperature and higher moisture content compared with the pillars in the front. The mean temperature of the entire time was similar for the meteorologies; however, the relative humidity differed. High relative humidity, greater than 70%, was observed frequently. In particular, it was determined that the termite activity days were the most inside the Josadang shrine. The statistical analysis confirmed that there was a difference between the meteorology events through the F ratio. In addition, the difference of environmental factors with relative humidity and temperature was identified more great difference in relative humidity through the t-statistics of temperature and relative humidity. And then relative humidity was confirmed most great in the difference of meso-meteorology and local-meteorology.

• Journal of Adhesion and Interface
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• v.13 no.4
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• pp.171-181
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• 2012

The demand characteristics of the conventional 12 kinds of epoxy resins which have been used for restoration of the ceramic relics were investigated to provide standards of the effective materials in this study. The result of durability analysis showed that a liquid type is more effective in ceramic relics (low damage, high strength), and a paste type is more effective in earthenware relics (high damage, low strength). The result of workability analysis appears that the liquid type is higher than the paste type, and a slow curing type is higher than a fast curing type in surface hardness. Therefore, in the case of the liquid type which is hard to reprocess due to high surface hardness, it is necessary to conduct a study on improving physical properties by adding filler. The result of the gloss analysis on epoxy resins showed that the liquid type (colorless) has higher gloss than the paste type, and the slow curing type has higher gloss than the fast curing type in liquid types. CDK-520A/520B and Araldite SV 427-2/HV 427-1 showed the most similar gloss to $700^{\circ}C$ earthenware, Devcon 5 minute, EPO-TEK 301-2, and Quik Wood showed the most similar gloss to celadon and whiteware, Quik Wood, EPO-TEK 301-2, and Devcon 5 minute showed the most similar gloss to buncheongware. It is necessary for conservator to decide the range of the restoration surface by predicting the increase and decrease of the restoration surface because most of the epoxy resins caused the volume change in curing process.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.44 no.4 s.316
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• pp.1-7
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• 2007

In this paper, we analyze geometrical relations of 3D shape reconstruction from 2D images taken under anne projection. The purpose of this research is to contribute to more accurate 3-D reconstruction under noise distribution by analyzing geometrically the 2D to 3D relationship. In situation for no missing feature points (FPs) or no noise in 2D image plane, the accurate solution of 3D shape reconstruction is blown to be provided by Singular Yalue Decomposition (SVD) factorization. However, if several FPs not been observed because of object occlusion and image low resolution, and so on, there is no simple solution. Moreover, the 3D shape reconstructed from noise-distributed FPs is peturbed because of the influence of the noise. This paper focuses on analysis of geometrical properties which can interpret the missing FPs even though the noise is distributed on other FPs.

• The KIPS Transactions:PartB
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• v.15B no.3
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• pp.205-210
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• 2008

A new approach is proposed for restoration of corrupted regions and segmentation in natural text images. The challenge is to fill in the corrupted regions on the basis of color feature analysis by second order symmetric stick tensor. It is show how feature analysis can benefit from analyzing features using tensor voting with chromatic and achromatic components. The proposed method is applied to text images corrupted by manifold types of various noises. Firstly, we decompose an image into chromatic and achromatic components to analyze images. Secondly, selected feature vectors are analyzed by second-order symmetric stick tensor. And tensors are redefined by voting information with neighbor voters, while restore the corrupted regions. Lastly, mode estimation and segmentation are performed by adaptive mean shift and separated clustering method respectively. This approach is automatically done, thereby allowing to easily fill-in corrupted regions containing completely different structures and surrounding backgrounds. Applications of proposed method include the restoration of damaged text images; removal of superimposed noises or streaks. We so can see that proposed approach is efficient and robust in terms of restoring and segmenting text images corrupted.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.31 no.12C
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• pp.1194-1200
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• 2006

In this paper, we propose an adaptive MAP (Maximum A Posteriori) high-resolution image reconstruction algorithm using local statistics. In order to preserve the edge information of an original high-resolution image, a visibility function defined by local statistics of the low-resolution image is incorporated into MAP estimation process, so that the local smoothness is adaptively controlled. The weighted non-quadratic convex functional is defined to obtain the optimal solution that is as close as possible to the original high-resolution image. An iterative algorithm is utilized for obtaining the solution, and the smoothing parameter is updated at each iteration step from the partially reconstructed high-resolution image is required. Experimental results demonstrate the capability of the proposed algorithm.

• Korean Journal of Environment and Ecology
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• v.17 no.3
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• pp.242-257
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• 2003

This study surveyed an ecosystem conservation area that is wetland area to establish ecological restoration and preservation plan. Monitoring standard have been set up item, method, period, number of times etc. Result that examine according to monitoring standard, Plant field investigated Flora, actual vegetation. Flora is 132 taxa(39 family 116 species 19 variety 1 forma) appeared and wild species were 85 species, and introduced species were 47 species. Grasped monthly(April∼September) actual vegetation, swampy plant community influence were increase and influence of Persicaria thunbergii was big situation specially. Frequency appearance of naturalized plant is much on field. Animal field investigated Birds, Herpetofauna, Insecta. Birds were appeared 34 species 378 individual and Herpetofauna were appeared 4 species 5 individual and insecta investigated 11 order 52 family 153 species. Inorganic environmental field investigated groundwater level, quality of water, soil quality. Groundwater level is high by 0.0∼89.0cm, $Ca^{++}$ content is some high by 2.18∼13.73cmol/kg in soil. Also we suggested basis direction and each space details plan on monitoring as follow : wetland ecosystem restoration plan, eruption area restoration plan, forest ecosystem restoration plan.n.

• Proceedings of the Korea Water Resources Association Conference
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• 2009.05a
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• pp.447-451
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• 2009

최근 들어 하천의 치수와 이수 그리고 환경적 측면을 고려한 "자연형 하천정비공사"가 활발히 이루어지고 있다. 그러나 개별적 특성이 뚜렷한 각각의 하천에서 그 하천을 기반으로 생활하는 생물들의 서식조건을 충분히 고려하였다고 보기는 어려운 상황이며, 제한된 공법의 사용으로 획일화된 인공하천 조성 및 관행적 하도정비에 그쳐 하도서식처가 빈번하게 교란되고 있는 것이 현실이다. 특히, 하천에서의 하도서식처는 하천을 서식기반으로 살아가는 생물들에게 생활사의 각 단계(먹이섭취, 휴식, 피난, 산란, 우화, 번데기)에서 이용하는 특정 장소로서 중요한 의미를 가지며 하천을 복원하는 하나의 목표이기도 하다. 본 연구는 대전에 위치한 갑천을 대상으로 하천을 서식기반으로 살아가는 생물들의 하도서식공간의 유형을 구분하고 각각의 서식처의 물리 화학 생태적 특성을 규명하고, 그 입지에 적응하며 서식하는 생물 상호간 생태적 연관성에 대하여 검토하였다.