• Title/Summary/Keyword: 난도

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Investigation on the Cause of Bad Natural Seed Collection of the Pacific Oyster, Crassostrea gigas: Relationships between the Conditions of Mother Shell and the Viability of the Released Eggs and Larvae Based on the Pathological and Embryological Survey (참굴 채묘 부진 원인 구명에 관한 연구 -병리 발생학적 조사를 통한 참굴 모패의 건강도와 난 및 유생의 생존율과의 상관관계 구명 -)

  • PARK Mi Seon;LYU Ho Young;LEE Tae Seek
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.32 no.1
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    • pp.62-67
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    • 1999
  • Infection rates of oyster ovarian parasite, Marteiliodes chungmuensis and productivity of the oyster shellstock infected with the parasite were investigated at the main seed collection areas in the southern coast of Korea where the extreme bad seed collection of oyster occurred in 1992 and 1993 to evaluate the cause of the bad seed collection. Additionally, the bacterial flora of the sea water and oyster lana were examined to identify the shellfish larva pathogenic bacteria like Vibrio sp. and Pseueomonas sp. In August 1992 to September 1993, infection rate of oyster ovarian parasite, M. chungmuensis at Tongyong, Kyongsangnam province, and Yosu, Chollanam province where the bad seed collection occurred, were $11.8\~100\%$ and $14.3\~100\%$, respectively. But the parasite was not detected in the shellstock collected at Daechon, Chungchongnam province. While a virus-like particle was identified in the cytoplasm of the egg infected by the parasite. The parasite infected egg was not able to fertilize completely. Uninfected egg in the gonad contaminated by the parasite could be able to fertilize but showed an abnormal development till D-shaped larva and then, died of necrosis after D-shaped lana. And some lana developed from low lipid content egg could not develop to the spat and died after the early umbo stage. The predominant bacteria in the oyster lana collected at bad seed collection areas were Pseudomonas sp. and Pseudomonas like bacteria and the occupancy rates were $53.3\~87.1\%$.

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민간 건설업체 택지난 허덕인다

  • Park, Jun-Hyeong
    • 주택과사람들
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    • s.197
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    • pp.74-75
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    • 2006
  • 민간 주택 건설업체에 택지난이 가중되고 있다. 이에 따라 건설 경기 활성화를 위해 택지 공급 방식을 개편하는 등 택지 공급을 늘리는 방안을 찾아야 한다는 목소리가 높아지고 있다.

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Isolations of Orchid Mycorrhizal Fungi from the Korean Native Orchid Plants (한국의 자생 난과식물에서 난균근균(蘭菌根菌)(Orchid Mycorrhizal Fungi) 분리)

  • Lee, Sang-Sun;Riew, Hee-Kyun;Paek, Kee-Yoeup
    • The Korean Journal of Mycology
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    • v.25 no.2 s.81
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    • pp.101-110
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    • 1997
  • This study was to identify the orchid mycorrhizal fungi and to test whether the orchid plants antificially inoculated with this fungus showed better growth them uninoculated plants. Symbioses in the root cells of the native plants of Cymbidium goeringii collected were observed and the digestive forms of peletons were also observed in various native roots. Two types of hyphae, thick $(7{\sim}10\;{\mu}m)$ and thin $(2{\sim}4\;{\mu}m)$ in thickness, were conclusively found to be from various native orchid roots. The symbiotic fungus was isolated by several agars and identified as a Rhizoctonia repens or a R. endophytica var. endophytica. Symbioses on the plantlets of C. karnan and Cymbidium hybrid 'Onomoron' were evaluated as the isolates inoculated on oatmeal agars. The growth of plantlets were measured with the formations of mycorrhizae in the roots. R. repens was shown to be the better isolate than the other in growth stimulation of plantlets on oatmeal agars when grown for two months. The two types of hyphae in the root cells under nature were speculated from the different fungal isolates of Rhizoctonia. Further isolates would be needed for application works for the orchid industries.

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Distributional Change and Climate Condition of Warm-temperate Evergreen Broad-leaved Trees in Korea (한반도 난온대 상록활엽수의 분포변화 및 기후조건)

  • Yun, Jong-Hak;Kim, Jung-Hyun;Oh, Kyoung-Hee;Lee, Byoung-Yoon
    • Korean Journal of Environment and Ecology
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    • v.25 no.1
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    • pp.47-56
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    • 2011
  • The research was conducted to find optimal habitats of warm-temperate evergreen broad-leaved trees, and to investigate climate factors to determine their distribution using classification tree (CT) analysis. The warm-temperate evergreen broad-leaved trees model (EG-model) constructed by CT analysis showed that Mean minimum temperature of the coldest month (TMC) is a major climate factor in determining distribution of warm-temperate evergreen broad-leaved trees. The areas above the $-5.95^{\circ}C$ of TMC revealed the optimal habitats of the trees. The coldest month mean temperature (CMT) equitable to $-5.95^{\circ}C$ of TMC is $-1.7^{\circ}C$, which is lower than $-1^{\circ}C$ of CMT of warm-temperate evergreen broad-leaved trees. Suitable habitats were defined for warm-temperate evergreen broad-leaved trees in Korea. These habitats were classified into two areas according to the value of TMC. One area with more than$-5.95^{\circ}C$ of TMC was favorable to trees if the summer precipitation (PRS) is above 826.5mm; the other one with less than $-5.95^{\circ}C$ of TMC was favorable if PRS is above 1219mm. These favorable conditions of habitats were similar to those of warm-temperate evergreen broad-leaved trees in Japan. We figured out from these results that distribution of warm-temperate evergreen broad-leaved trees were expanded to inland areas of southern parts of Korean peninsula, and ares with the higher latitude. Finally, the northern limits of warm-temperate evergreen broad-leaved trees might be adjusted accordingly.

Relighting Using Diffuse and Specular Radiance Map (난반사와 거울반사 라디안스 맵을 이용한 재조명)

  • 정기숙;김모곤;정순기
    • Proceedings of the Korean Information Science Society Conference
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    • 2001.10b
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    • pp.499-501
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    • 2001
  • 본 논문에서는 각 광원의 위치에 대해 미리 구한 라디안스 맵에 시간-색 공간에서의 반사요소 분리방법을 적용하여 난반사 라디안스 맵과 거울반사 라디안스 맵을 구한다. 필셀 BRDF를 얻기 위한 입력으로 반사요소가 분리된 라디안스 맵을 사용하였다. 따라서, 광원의 조작에 대해 난반사와 거울반사 이미지를 각각 제어할 수 있다. 시간-색 공간에서의 반사요소 분리방법을 사용함으로써, 이미지의 전역 정보가 아니라 지역 정보만을 이용한 반사요소 분리가 가능하다.

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레이저 표면 거칠기 측정에서 가중 함수에 의한 반사광 성분의 블렌딩

  • 서영호;안중환
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2004.05a
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    • pp.171-171
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    • 2004
  • 반사광은 표면에 대한 다양한 정보를 포함하고 있다. 반사광 속에서 표면의 거칠기 정보를 알아내 기 위한 노력이 계속되었고, 이를 통해 여러 표면 거칠기 측정법 중에서도 인프로세스 측정에 큰 장 점이 있는 것으로 밝혀졌다. 알려진 바로는 하나의 반사광을 정반사 성분와 난반사 성분으로 구분할 수 있으며 정반사 성분은 광 강도가, 난반사 성분은 광 분포가 중요하다. 매끈한 면에서는 정반사 성분이 지배적이며, 거친 면에서는 난반사 성분이 지배적이고, 그 중간 단계의 면에서는 두 성분이 합해져서 동시에 나타난다.(중략)

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SRAM Reuse Design and Verification by Redundancy Memory (여분의 메모리를 이용한 SRAM 재사용 설계 및 검증)

  • Shim Eun sung;Chang Hoon
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.30 no.4A
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    • pp.328-335
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    • 2005
  • bIn this paper, built-in self-repair(BISR) is proposed for semiconductor memories. BISR is consisted of BIST(Buit-in self-test) and BIRU(Built-In Remapping Uint). BIST circuits are required not oがy to detect the presence of faults but also to specify their locations for repair. The memory rows are virtually divided into row blocks and reconfiguration is performed at the row block level instead of the traditional row level. According to the experimental result, we can verify algorithm for replacement of faulty cell.

분화와 발생양상의 조절기작에 관한 연구: 자외선 조사와 수정난의 회전이 배, 복축 극성의 결정에 미치는 영향

  • 정해문
    • The Korean Journal of Zoology
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    • v.25 no.3
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    • pp.107-114
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    • 1982
  • A combination of ultraviolet irradiation and egg rotation was applied to Korean frogs to study the mechanisms of the establishment of the dorsal-ventral polarity. Rotation of the uncleaved egg was capable of preventing the characteristic syndromes associated with UV irradiation. As well, brief rotation of the egg before cleavage relocates the site of dorsal lip to a novel location in the embryo at gastrula stage. That is, the dorsal lip appeared on the opposite side to gravity at the rotation of the egg. Above results were discussed with the informations obtained from other anuran and urodele species, and were interpreted in terms of regulating mechanisms for early embryogenesis.

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Separation of Diffuse and Specular Reflection for Image-Based Relighting (영상기반 재조명을 위한 전반사와 난반사 성분의 분리)

  • Lee Byoung-Hwa;Park Jong-Il;Lee Sang Hwa
    • Proceedings of the Korean Society of Broadcast Engineers Conference
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    • 2003.11a
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    • pp.37-42
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    • 2003
  • 전반사는 물체의 사실적인 모습을 나타내는데 중요한 요소이지만 컴퓨터 비전에서는 처리하기 어려운 장애 요소이다. 본 논문에서는 영상기반 재조명을 위하여 조명 조건이 다른 복수의 영상으로부터 전반사 성분과 난반사 성분을 분리하는 효과적인 알고리즘을 제안한다. 이 알고리즘은 전반사 성분이 존재하는 영상과 난반사 성분만이 존재하는 영상에 대하여 난반사 성분의 RGB 값은 서희 비율을 유지하면서 변한다는 성질을 이용하여 전반사 성분을 분리한다. 그리고 실험을 통하여 이 알고리즘의 유효성을 확인하였다.

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