• Journal of the Korean Society for Nondestructive Testing
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• v.21 no.6
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• pp.658-662
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• 2001

The classification of surface flaw types was performed on the basis of angular dependence of backscattered ultrasound. The copper line adhered on the surface, cower line filled in groove, pure groove and the normal edge were adopted as various surface flaw patterns of glass specimen. A backward longitudinal profile was formed probably by the longitudinal wane scattering at and near 1st critical angle. The wave trains at the peak angles of the backward radiation profiles showed different shapes according to the superposition ratio of scattered and leaky waves. The asymmetry of the backward radiation profile arose due to the scattering effect of flaw. The additive resonance effect of copper line appeared in the left side of the profile. The peak angles of both the longitudinal and radiation profiles were shifted toward small angle by the scattering effect.

• KOREAN POULTRY JOURNAL
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• v.28 no.11 s.325
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• pp.107-112
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• 1996

• KOREAN POULTRY JOURNAL
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• v.28 no.3 s.317
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• pp.140-147
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• 1996

• Korean Journal of Environment and Ecology
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• v.27 no.2
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• pp.209-218
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• 2013

This study was conducted to analyze the characteristics of odonata communities as habitat types in Wonju City, Korea. The 33 plots were installed at 4 types of biotope like abandoned paddy fields, natural type reservoir, natural type river and forest valley in Wonju city. From the survey, the 9 family and 38 species were identified. As the result of comparative investigation of the species composition of each habitat through TWINSPAN analyzing, the difference of species composition was definite in abandoned paddy field, natural type reservoir and forest valley, however, it was uncertain in natural type river. The dominant species and the subdominant species of each habitat were mainly Sympetrum frequens and Sympetrum infuscatum but the distributions of Paracercion hieroglyphicum, Epophthalmia elegans, and Anax parthenope julius were different as haibtat types. The order of the index of species diversity was not different between abandoned paddy fiedls, natural type reservoir and natural type river, but forest valley was low. The abandoned paddy field was shown the most diverse spawning type of odonata, it is considered that hydrophyten play an important role in the abundant of odonata since the sorts of odonata spawning in plants are majority. As the result of analyzing interspecies relationship, Crocothemis servilia mariannae and Orthetrum albistylum, Crocothemis servilia mariannae-Platycnemis phyllopoda, Lyriothemis pachygastra-Sympetrum parvulum are shown the positive correlation, however, they have a difference in preferred habitat between high correlation species.

• Korean Journal of Environment and Ecology
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• v.28 no.3
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• pp.293-301
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• 2014

15 artificial ponds in Seoul have been examined to find out the characteristics of Odonata community according to age and size of pond. We found 6 Families 36 Species of Odonata community, and Libellulidae was the most frequent and 19 Species were observed among Libellulidae. Considering relative importance with frequency of appearance and density, Ischnura asiatica and Orthetrum albistylum was the most frequent. Also, 16 Species including Lestes temporaris, Sympetrum parvulum, and Anax nigrofasciatus were relatively rare. The result of dominant species tells that Ischnura asiatica in 1 ~ 3 year old ponds, Pantala flavescens-Orthetrum albistylum-Crocothemis servilia mariannae in order of mention in 4 ~ 6 year old ponds, Platycnemis phyllopoda-Ischnura asiatica in order of mention in 10 or more year old ponds are the dominant species. Species diversity index regarding age of pond has been researched, and species diversity index in 10 year old pond was higher than that of in 1 ~ 3 year old pond. Having done the analysis of variance for types of spawn, there are many species Endophytic egg-layers and pasting in mud or sand in 10 year old artificial ponds. The wider ponds get, the higher species diversity index gets. And, we suggest that desirable size for making artificial ponds to increase the species diversity index of Odonata is $100{\sim}300m^2$.

• KOREAN POULTRY JOURNAL
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• v.13 no.2 s.136
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• pp.52-54
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• 1981

1978년 후반기부터 우리 나라에 발생하여 혈청학적으로 확인된 후 계속적으로 채란 양계농가와 종계에 심각한 피해를 주고 있는 EDS '76이 아직 적절한 방역대책이 마련되지 않은 채 불황속을 헤메고 있는 채란 양계업계에 검은 그림자를 던져주고 있다. 본지는 경기도 전역을 두루 현지 취재하여 발병유형과 피해도를 조사하여 보았다.

• 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.

• Korean Journal of Optics and Photonics
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• v.21 no.6
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• pp.225-229
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• 2010

Laser-induced scatterer patterns in a light guide panel(LGP) have provided partially concentrated light distribution, especially near the light entrance of the LGP. Additional treatments for enhancing performance of the LGP, such as gradually increased processing depth, were also developed, but minor improvement was observed in the fabricated LGP. To solve this problem, we designed a revised scatterer pattern to be inscribed into the LGP using different laser processing depths and different separation distances between patterns. Performance feasibility of the proposed pattern was analyzed with simulation before laser inscription in the LGP. The LGP inscribed with the proposed scatterer patterns contributes improvements in luminance and uniformity of the LGP.

• Journal of Animal Environmental Science
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• v.11 no.1
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• pp.35-44
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• 2005

The objectives of this study were to develop an image processing algorithm for finding the sick or the dead layers(SDL) rearing in the multi-tier layer battery, which is a core technology of remote monitoring systems for layers, and to test the performance of algorithm developed in the experimental poultry housing. Based on the literature study and experiment, the standing up of layer was set as a criterion for judging layers whether sick or dead. Then, by the criterion set, an algorithm was developed. The image processing algorithm developed was tested how well it could and SDL at the experimental poultry housing. Test results showed that its monitoring correctness of layers standing up in the cages having all healthy layers was $92\%$, and $96\%$ in the cages having SDL. Therefore, it would be concluded that the image processing algorithm developed in this study was well suited to the purpose of development.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.62 no.9
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• pp.1260-1263
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• 2013

Plane wave scattering from a spherical resonator is calculated by solving the combined field integral equation (CFIE) with Rao-Wilton-Glisson (RWG) basis functions and the moment method. The calculations show that magnetic and electric dipoles are found at resonant modes. These characteristics are confirmed by radiation patterns in the far field region. In addition, an analysis of a magnetodielectric sphere is discussed.