• Korean Journal of Ichthyology
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• v.4 no.1
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• pp.87-95
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• 1992

Diurnal variation of fish assemblage in the coastal waters, Shinsudo, Samchonpo was investigated using samples collected by RN 80net. A total of 32 species in 24 families was classfied from samples collected during the period of investigation. Enedrias nebulosus, Acanthogobius flavimanus, callionymus sp. dominated in number of individuals. These three most abundant fish species accounted for approximately 55.3% of the total number of fish collected. The percentage similarity values of number were larger than those of biomass. The catches in January and May 1987 showed a significant difference between day and night compositions. The number of species and individuals peaked just after twilight and low tide.

• Proceedings of the Materials Research Society of Korea Conference
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• 2003.11a
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• pp.213-213
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• 2003

고온 및 고압의 가혹한 방사선 분위기에서 사용되는 핵연료 피복관은 중성자 조사 및 수소화합물의 생성 등으로 인하여 기계적 성질이 저하된다. 따라서 조사된 핵연료 피복관의 손상기준 확립과 안전성 해석을 위해서는 연성 및 강도 등 기계적 특성을 정확히 이해하여야 할 필요가 있다. 핵연료 피복관의 종 및 횡 방향 인장특성 평가를 위하여 개발된 기존의 다양한 시험법들을 비교하고, 핫셀시험에 적합한 인장시험법을 개발하였다. 피복관의 종방향 인장시편은 튜브시편 또는 게이지부 내에서 균일한 변형률 분포를 얻도록 설계된 도그본 튜브시편(그림 1)을 사용한다. 피복관의 횡방향 인장시험에 사용되는 링시편(그림 2)은 게이지부 내에서 균일한 단축 원환변형율 분포 또는 평면변형율 조건을 나타내도록 설계한다. 연소 또는 조사된 피복관으로부터 시편을 제작하기 위해서는 핫셀 내에서 작업 이 가능한 방전가공기(그림 3)를 사용한다. 피복관의 종방향 인장시험용그립(grip)은 핀-부하형이며, 횡방향 인장시험의 경우는 시험 동안 시편의 곡률이 일정하게 유지 되도록 그립의 형상 및 치수를 결정한다(그림 4). 피복관의 종 및 횡방향 강도와 변형 등 기계적 특성을 평가하기 위한 응력-변형율 곡선은 시험기의 복합 강성(K)을 고려하여 결정한다. 이상과 같이 검토된 인장시험법은 피복관의 안전성 해석(safety analysis)과 관련 규정(regulatory)에서 사용되는 피복관 손상기준(fuel damage criteria)의 개선에 필수적인 자료를 제공한다.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.35 no.1
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• pp.57-63
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• 2002

The marine algal flora and community of uninhabitated islands in Haenamgun, southern coast of Korea, were investigated during 12$\~$29, June, 1999. As the results, a total of 87 species including 10 greens, IS browns and 62 reds was identified. The dominant species were Ulva pertusa and Sargassum thunbergii and the subdominants were Myelophycus simplex, Ishige okamurae, Hizikia fusifomis, Gloiopeltis furcata and Chondracanthus intermedius. The vertical distribution pattern of intertidal marine algae represented three distinct zones; Gloiopeltis furcata, Caulacanthus okamurae, Myelophycus simplex-Gloiopeltis complanata, G. tenax, Gelidium divaricatum, Ulva pertusa, Sargassum thunbergii-Hizikia fusiformis, Pelvetia babingtonii, Chondrus ocellatus, Undaria pinnatifida, Ecklonia lava from upper to lower zones.

• Animal Systematics, Evolution and Diversity
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• v.17 no.2
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• pp.191-205
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• 2001

This study includes the taxonomy, description, and a key to species of mites in the Family Zerconidae(Acari, Mesostigmata) from the Korean Peninsula. Materials examined and information gathered were based on 1,020 specimens which has been collected nation-wide from April, 1994 to May, 2000. As a result of this study, the following 8 species were identified : Exhinozercon orientalis Blazak, 1975, Eurozercon pacificus Halaskova, 1979, Kaikiozercon mamillosus Halaksova, 1979, Kaikiozercon peregrinus Halaskova, 1979, Koreozercon bacatus Halaskova, 1979, Mesozercon coeranus Blaszak, 1975, Mesozercon plumatus (Aoki, 1966), Zercon szeptyckii Blaszak, 1976. Predominant species was Zercon szeptyckii which has been collected more then 600 specimens at 25 localities in the Korea Peninsula. Seven species except Mesozercon plumatus(Aoki, 1966) had been recorded from North Korea but newly recorded from the southern part of Korean Penunsula.

• Research in Plant Disease
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• v.7 no.1
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• pp.49-55
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• 2001

Species and races of root-knot nematodes in greenhouses in southern Korea were investigated and a simple identification scheme was provided. Among 23 populations of root-knot nematodes, Meloidogyne arenaria race 2 was 59%, M. incognita race 1 was 23%, and an unknown race of M. incognita was 18%. Total length of M. arenaria juveniles was 411㎛(306-503㎛) and that of M. incognita was 384㎛(312-488㎛); however, the ranges of two species were overlapped and could not be used to distinguish the two species. Excretory pore in female head was a consistent character to differentiate M. arenaria and M. incognita.

• Korean journal of applied entomology
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• v.20 no.3 s.48
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• pp.155-167
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• 1981

This paper deals with the Triozidae of Korea A total of 20 species belonging to 5 genera are recognized, among them 6 species are new to science as: Bactericera (S.) distinctissima n. sp., B. (S.) miyatakei n. sp., B. (S.) yamagishii n. sp., Heterotrioza (D.) noknamui n. sp., Trioza breviata n. sp., and T. mayicola n. sp., 4 species are newly recorded from Korea as: Epitrioza yasumatsui Miyatake, 1978, Bactericesa (S.) calcarata (Schaefer, 1949), B, (S.) striola (Flor, 1861), and Trioza abdominalis Flor, 1861, and a new combination is made to: Heterptrioza (D.) chilgia (Park et Lee, 1980) n. comb. Keys are provided to the genera and species respectively Some illustartions of head, forewing, male and female genitalic characters are given.

• Journal of the Korean Geographical Society
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• v.37 no.4
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• pp.357-370
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• 2002

Present work aims to investigate the species composition, physiognomy and distribution of arctic-alpine and alpine plants(AAP) of the Korean Peninsula. The dominance of AAP in the northern Korea may be due to the frequent exchanges of floras with circumpolar regions for the seek of the glacial refugia during the alternate Pleistocene glacial epochs. The post-glacial climatic amelioration pushed AAP back northwards and upwards, so they now shows disjunctive distribution on separate mountain tops. The diverse morphological adaptations of AAP to severe environmental conditions, viz. the dominance of perennial species, stunted tree growth, multiple protection of leaves, krummholz, and dwarf shrubs, are the result of long-term graduall development which have safeguarded the survival of AAP in a such a harsh cryo-climatic area. The appearance of the Korean endemic AAP reflects the long-term isolation of species in Korea, and the local environmental diversities which have both accentuated this isolation and aided the development of genetic diversity. Evergreen broad-leaved AAP at c. 1,500m to 1,800m and above are now endangered because of the competition from down-slope plants, and from the global warming.

• Korean Journal of Environmental Biology
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• v.19 no.4
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• pp.282-291
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• 2001

The distribution and standing crop of phytoplankton were investigated seasonally at 6 stations in the nearby streams of Suwon sewage disposal plant. It turned out to be total of 176 taxa, and classified as 4 phylums, 4 classes, 11 orders, 6 suborders, 22 families, 54 genera, 155 species, 20 varieties and 1 form by Engler's classification system. Among 176 taxa, 22 including Microcystis Aphanizomenon flos-aquae were identified as indicators of water pollution. Standing crops of all stations investigated appeared to be relatively high as in other streams through the center of the city, such as Kyoungan-chon of Youngin-si and Gulpo-chon of Buchon-si. In station 1,2,4 and 6, the highest number of standing crop were shown in summer, while in station 3 and 5, it was high in winter. Based on the present study upon the distribution and standing crop of phytoplankton, it is regarded as the state of the eutrophication in the nearby streams of Suwon sewage disposal plant.

• Korean Journal of Weed Science
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• v.12 no.1
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• pp.46-51
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• 1992

The survey of weed population in paddy field was carried out to invegstigate the weed group on 340 fields in Kyonggi Area in 1991. The weed species observed include 4 species of grasses, 7 species of sedges, and 14 species of broadleaf weeds, and the ratio of annual weed vs perennial weed was 25 : 75. Major dominant weed species were Eleocharis kuroguwai, Sagitaria trifolia, Echinochloa crusgalli and Cyperus serotinus. The dominant weed species in South Plain Region were Echinochloa crusgalli, Eleocharis kuroguwai, Sagitariu trifolia, Cyperus strotinus, in West Coast Region were Eleocharis kuroguwai, Sagitaria trifolia, Echinochloa crusgalli, Cyperus serotinus, in East Interior Region were Eleocharis kuroguwai, Sagitaria trifolia, Echinochloa crusgalli, Cyperus difformis and were Sagitaria trifolia, Eleocharis kuroguwai, Echinochloa crusgalli and Monochoria vaginalis in North Region. The dominant weed species in Normal and Poorly drained soil were Eleocharis kuroguwdi, Sagitaria trifolia, Echinochloa crusgalli and Cyperus serotinus and were Scirpus maritinus, Cyperus serotinus, Echinochlod crusgalli and Myriophyllum verticillatum in Saline Soil. More and many weeds were growing in single cropped field than double cropped field.

• Korean Journal of Plant Resources
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• v.15 no.2
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• pp.114-122
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• 2002

This study investigated the species composition and distribution of woody plants, and flora of vascular plants of Cheonjiyeon where is located in the most southern region of Korea. Twenty-nine taxa of trees were distributed in the valley, and of these, deciduous broad-leaved trees were 13. Of the total number of 2,547 trees, 1,429 were deciduous broad-leaved trees and remainder was broad-leaved evergreen. Deciduous broad-leaved trees covered 48.7% of the tree canopy while evergreen broad-leaved trees covered only 42.3%. The total number of shrub taxa was 37 with more evergreen shrub taxa than deciduous. Evergreen shrubs occupied 64.4％ of shrub canopy while deciduous shrubs covered only 35.4％. The result of the investigation of flora showed that there are 446 taxa of flora including 114 families, 320 genera, 397 species, 1 subspecies, 39 varieties, and 9 forma. Of these, two species, Rubus hongnoensis Nakai and Lycoris chejuensis K. Tae et S. Ko, are endemic plants of Jeju Island. The flora includes 17 taxa of rare plants that are distributed only in Jeju Island in Korea. Also, the flora includes 1 taxon, Elaeocarpus sylvestris (Loureiro) Poiret var. ellipticus (Thunb.) Hara, of Korean natural monument, 2 taxa, Psilotum nudum (L.) Griseb. and Crypsinus hastatus (Thunb.) Copeland, of legally protected wildlife and plants, 38 taxa of naturalized plants, and 75 taxa of introduced plants.