• Animal Systematics, Evolution and Diversity
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• 제13권4호
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• pp.285-290
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• 1997

우리나라의 서해연안에서 채집된 상어류 2개체는 아직까지 국내에서는 보고된 바 없는 Sphyrna lewini(Griffith and Smith)와 Alopias vulpinus(Bonnaterre)로 동정되었다. S. lewini는 귀상어(S. zygaena)와 유사하지만 두부의 중앙부가 함입되엉 있고, 제2등지느러미 끝이 거의 꼬리지느러미에 달한다는 점에서 귀상어와 구분되었다. A. ulpinus는 환도상어(A. pelagicus)와 유사하지만 복부의 흰색이 가슴지느러미 기부 위까지 확장되고, 입의 양쪽 끝에 입술주름이 있어서 환도상어와 구분되었다.

• 한국광물학회지
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• 제15권3호
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• pp.171-181
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• 2002

포항지역 제3기 해성퇴적층에서 산출되는 해록석의 생성과정을 해록석 형태와 화학분석에 의하여 연구하였다. 사암 내에서 산발적으로 산출되는 해록석은 뚜렷한 두 단계의 광물형태와 성분변화가 나타난다. 해록석의 결정화는 펠 형태 입자의 내부에서 우선적으로 시작되어 외부쪽으로 K와 Fe 성분이 증가하고 Al 성분이 감소하는 경향을 보인다 더욱이 스멕타이트와 비슷한 조성의 해록석은 K와 Al 성분이 증가하고 Fe 성분이 감소하면서 해록석/스멕타이트 혼합층광물 단계를 거쳐서 일라이트와 비슷한 조성의 해록석으로 진화하여 간다.화하여 간다.

• 유변학
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• 제10권4호
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• pp.247-255
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• 1998

이축 압출기에서 삼성분계 블렌드가 용융 혼련될 때 상구조의 형성과정에 대하여 연구하였다. 삼성분계 블렌드의 연속상은 polycarbonate(PC)로 고정하였고 나머지 분산상을 이루는 성분으로는 acrylonitrile-butadiene-styrene(ABS), methyl methacrylate-butadiene-ethyl acrylate(MBE), styrene-acrylonitrile(SAM) 공중합체, 그리고 poly(methyl methacrylate)(PMMA)를 사용하였다. 블렌드의 여러 가지 조성에 따라 최종 상구조는 현저한 차이를 보였고 특히 MBE와 PMMA의 경우는 각각 PC-SAN의 계면에 선택적으로 위치하였다. 삼성분계 고분자 블렌드의 상구조 형성과정은 성분간의 계면장력과 합체 현상의 상호 작용에 의하여 지배되었으며 합체의 정도는 계면에서의 점도에 의하여 민감하게 변화되었다.

• Animal Systematics, Evolution and Diversity
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• 제28권1호
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• pp.29-35
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• 2012

Two Spirostomum species collected from freshwater in Korea were identified as S. caudatum (Muller, 1786) and S. teres (Claparede and Lachmann, 1858). They are recorded for the first time in Korea. The description was based on the observation of living specimens and protargol impregnated specimens. Diagnostics of these species are as follows. Spirostomum caudatum: body size $400-450{\times}20-30\;{\mu}m$ in vivo, shaped long and slender with a tapered posterior part, highly contractile; macronucleus ellipsoid; adoral zone of membranelles occupied 30% of body length; somatic kineties 14-22 in number. Spirostomum teres: body size $240-460{\times}25-40\;{\mu}m$ in vivo, shaped long and slender with a flattened posterior end, highly contractile; cortical granules arranged in 2-3 rows; adoral zone of membranelles occupied 50% of body length; somatic kineties 20-30 in number; macronucleus ellipsoid; micronuclei 2-3 in number. Spirostomum caudatum and S. teres are the most similar congeners, but they are different in the posterior part of body (tail-like posterior part vs. flattened posterior end), length of adoral zone of membranelles in body length (1/3 vs. 1/2), and the number of somatic kineties (14-22 vs. 20-30). These populations match with European populations in morphological characters.

• Animal Systematics, Evolution and Diversity
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• 제28권2호
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• pp.126-132
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• 2012

A new monstrilloid species belonging to the genus $Cymbasoma$ is described as a preliminary result from nocturnal surveys using a light trap on the east and south coasts of South Korea. Monstrilloid copepods are first recorded in South Korea. $Cymbasoma$ $striifrons$ n. sp. resembles $C.$ $striatum$ (Isaac, 1974) and $C.$ $tumorifrons$ Isaac, 1975 in sharing the character combination of transverse striations on forehead, somewhat small body (generally slightly less or longer than 1 mm), single lobed leg 5 bearing a short medial seta in female, and smooth lateral margin of anal somite without notch and wrinkles. However, $C.$ $striifrons$ n. sp. differs from $C.$ $striatum$ by relatively short and swollen cephalothorax, and rather strongly wrinkled genital somite. $Cymbasoma$ $striifrons$ n. sp. is also distinguished from $C.$ $tumorifrons$ in lacking a rounded protuberance on anterior margin of ventral surface and by relatively short cephalothorax and the number of ventral nipple-like processes on cephalothorax. Herein the new species is described and illustrated, with some comments on the morphological comparison with its allied species.

• Water Engineering Research
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• 제6권1호
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• pp.17-30
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• 2005

The bed evolution of the stretch of the River Rhine between km-812.5 and km-821.5 is characterised by general bed degradation as a result of the river training works and dredging activities of the last two centuries. The degradation of the river bed affects the water levels, and so the navigation conditions. To combat the erosion of the river bed with the aim to keep up the shipping traffic and to avoid the ecological system damages due to water level reductions, sand-gravel-mixtures were added to the river (so called artificial grain feeding activities). This paper presents the results of an application of a graded sediment transport model in order to study morpholodynamical characteristics due to artificial grain feeding activities in the river stretch. The finite element code TELEMAC2D was used for flow calculation by solving the 2D shallow water equation on non-structured grids. The sediment transport module SISYPHE has been developed for graded sediment transport using a multiple layer model. The needs to apply such graded sediment transport approaches to study morphological processes in the domain are discussed. The calculations have been carried out for the case of middle water flow and different size-fraction distributions. The results show that the grain feeding process could be well simulated by the model.

• Animal Systematics, Evolution and Diversity
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• 제21권1호
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• pp.93-110
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• 2005

한국 담수산 검물벼룩류에 대한 분류학적 연구의 일환으로, 보통검물벼룩(Mesocyclops)속의 5종을 분류하였다: 보통검물벼룩 (M. leuckarti) 갈고리보통 검물벼룩 (M. pehpeiensis), 꼭지보통검물벼룩 (M. dissimilis), 민가시보통검물벼룩 (M. woutersi), 털줄보통검물벼룩 (M. mariae). 이 중 뒤의 3종은 한국미기록 종이다. 이들 5종의 분류학적 미세 형질과 종내 변이성을 검토하였다. 한국산 보통검물벼룩속의 종 검색표를 작성하였다.

• Animal Systematics, Evolution and Diversity
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• 제21권2호
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• pp.193-199
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• 2005

Liomerinae아과에 속하는 Liomera bella 제1조에아 유생을 처음으로 기재 및 도시하였다. 이 유생의 형태적 특징들을 부채게과의 다른 종들의 유생들과 비교하였다. 일반적인 형태면에서 본 유생은 부채게과 유생들과 잘 일치하였다. 또한 제2촉각 외지에 2개의 강모를 가지고, 제2악지 내지 말단 강모수가 6개이며, 미절에 1개의 센 측가시와 1개의 작은 측가시를 가짐으로서 Xantho incisus와 Pseudomedaeus agassizii 유생들과 더 큰 유사성을 보여주었다

• Animal Systematics, Evolution and Diversity
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• 제28권3호
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• pp.149-160
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• 2012

Heterotrichous ciliates were isolated from marine and brackish habitats in Korea, and their morphology, infraciliature and morphometrical characters were investigated using silver impregnated methods. These three Condylostoma species were identified as Condylostoma curva Burkovsky, 1970, C. minutum Bullington, 1940 and C. spatiosum Ozaki and Yagiu in Yagiu, 1944. The species of Condylostoma based on morphology are highly variable in most of characters and distinguished as following. Condylostoma curva is oval to elongate ellipsoidal, size about $245{\times}100{\mu}m$ in vivo, and conspicuously dark greenish brown with cortical granules on their surface, buccal cavity relatively large about 40% of body length, 5-11 macronuclear nodules, 4-8 frontal cirri serially arranged and 22-38 somatic kineties. Condylostoma minutum is elongate ellipsoidal and the size about $310{\times}55{\mu}m$ in vivo, buccal field about 35% of body length, 12-20 macronuclear nodules, adoral zone consisted of 82-107 membranelles, large and long one frontal cirrus and 38-44 somatic kineties. Condylostoma spatiosum is large elongate ellipsoidal, size about $670{\times}105{\mu}m$ in vivo, buccal cavity about 25% of body length, 11-25 macronuclear nodules, 111-144 adoral membranelles, membrane-like 2 frontal cirri, 49-74 somatic kineties. These three Condylostoma species are described here for the first time in Korea.

• Animal Systematics, Evolution and Diversity
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• nspc9호
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• pp.1-9
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• 2016

Two Spirostomum species were collected from freshwater in Jindo Island, Korea and identified as Spirostomum ambiguum (Muller, 1786) Ehrenberg, 1835 and Spirostomum minus Roux, 1901. This study is the first known morphological record of these two species being found in Korea. The description is based on the observation of living specimens and protargol impregnated specimens. Diagnostics of Spirostomum ambiguum: body size $340-930{\times}45-80{\mu}m$ in vivo; long and slender body with truncated posterior part; macronucleus moniliform with 7-22 nodules; cortical granules irregularly arranged 4-5 rows in between somatic kineties; 24-58 somatic kineties arranged longitudinally; adoral zone of membranelles (AZM) covered about 60-80% of body length. Diagnostics of Spirostomum minus: body size $500-730{\times}35-45{\mu}m$ in vivo; long and slender body with truncated posterior part; macronucleus moniliform with 11-16 nodules; micronucleus 20-37 oval shape; cortical granules regularly arranged 3-4 rows in between somatic kineties; 20-30 somatic kineties arranged longitudinally; AZM covered about 40-50% of body length with 120-150 adoral membranelles.