• Animal Systematics, Evolution and Diversity
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• 제39권4호
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• pp.176-211
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• 2023

Nine copepod species of the family Artotrogidae Brady, 1880 are described or redescribed from Korea. Included new species are two in the genus Artotrogus Boeck, 1859, one each in the genera Bradypontius Giesbrecht, 1895, Cryptopontius Giesbrecht, 1899, Neopontius Scott T., 1898 and Chejupontius n. gen., and two in the genus Sewellopontius Ummerkutty, 1966. Chejupontius n. gen. resembles Ascidipontius Kim I. H., 1996, Pulicitrogus Kim I. H., 1998, and Sewellopontius in having reduced armature of leg 1, but is distinguished from these and other genera of the family by the large, mediodistally expanded protopod of leg 5 and by a combination of characters exhibited in leg 1 that the first exopodal segment lacks an inner seta, the second exopodal segment lacks an outer spine, the third exopodal segment is armed with three spines plus one to three setae, and the second endopodal segment is armed with a single inner seta. Pteropontius cristatus Giesbrecht, 1895 known previously only from the Mediterranean Sea is redescribed, based on a newly collected specimen from Korea, and P. trimerus Kim I. H., 1996 is removed to the genus Sewellopontius. A short note is given for the epibiotic suctorian Thecacineta calix (Schroder, 1907) which was found attached to the antennule of a new copepod species.

• 인지과학
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• 제22권3호
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• pp.235-254
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• 2011

양안 부등 정보가 네온 색 확산에 미치는 영향을 알아보기 위해 두 편의 실험을 수행하였다. 자극으로는 Redies와 Spillmann(1981)의 연구에서 사용된 네온 색 확산 자극에 유도 선분과 분절을 추가하여 변형시킨 자극을 사용하였다. 실험1은 선분을 바깥 분절, 가운데 분절, 안쪽 분절 세 부분으로 나누어 각 분절의 양안 부등 정보를 달리하였을 때 네온 색 확산이 어떻게 달라지는지 살펴보았다. 실험 2에서는 다른 깊이 평면에 추가된 분절이 네온색 확산에 미치는 영향을 알아보았다. 실험 결과 모든 분절이 동일한 평면에 놓일 때 가장 선명하게 색 확산이 지각 되었으며 색 분절이 다른 분절들보다 가까이 있는 경우나 멀리있는 경우에는 색 확산이 약화되었다. 분절을 추가한 경우에는 추가된 분절이 네온 색 확산평면보다 앞쪽이든 뒤쪽이든 상관없이 네온 색 확산이 감소하지만 안쪽 분절이 추가된 경우보다 바깥쪽 분절이 추가되었을 때 네온 색 확산에 더 큰 영향을 미치는 것으로 나타났다. 이러한 결과는 네온 색 확산 현상이 깊이 정보에 의해 영향을 받을 수는 있지만 깊이처리 이전 단계의 정보처리에 더 크게 영향 받음을 시사한다.

• 환경생물
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• 제35권1호
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• pp.64-82
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• 2017

Two species of the minuta-subgroup within the oncaeid copepod genus Triconia $B{\ddot{o}}ttger$-Schnack, 1999 collected in the equatorial Pacific Ocean are newly recorded. A female T. minuta (Giesbrecht, 1893 ["1892"]) and both male and female T. umerus ($B{\ddot{o}}ttger$-Schnack and Boxshall, 1990) from the northeast equatorial Pacific are redescribed with the comparison of its morphological details, which differs from previous studies, in terms of the larger body size, the length to width ratio of the genital double-somite, the relative length of the outer basal seta on P5, and the ornamentation of the appendages. The characters, which are used for identification, such as the length ratio of the outer subdistal and outer spine versus the distal spine on P3-P4, and the outer spine length of the middle exopodal segment on P3 and P4 are reported for the first time. Information on the variations in the endopodal spine lengths of swimming legs 2-4 is also provided for T. minuta and T. umerus, with the summary of the wide zoogeographical distribution of these two species.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2002년도 춘계학술대회 논문집
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• pp.117-120
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• 2002

In this study the occlusion of dural-sac, the outer membrane of spinal cord in the lumbar region, was quantitatively analyzed using one motion segment finite element model. Occlusion was quantified by calculating cross sectional area change of dural-sac far different compressive impact duration(loading rate) due to bony fragment at the posterior wall of the cortical shell in vertebral body. Dural-sac was occluded most highly in the range of 8∼12 msec impact duration by the bony fragment intruding into the spinal canal. t=400 msec case 4% cross sectional area change was calculated, which is the same as the cross sectional area change under 6 kN of static compressive loading.

• Animal cells and systems
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• 제16권1호
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• pp.57-68
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• 2012

Two new harpacticoid species belonging to the genera $Microarthridion$ Lang, 1944 (Tachidiidae) and $Nitocra$ Boeck, 1864 (Ameiridae) are recorded from underground caves in the karst area of Ninh Binh Province, North Vietnam. $Microarthridion$ $thanhi$ n. sp. is distinguished from congeneric species by the number of setae on the antennary exopod, the structure of leg 5 in both sexes, and the finger-like process modified from an outer distal pinnate seta of the third endopodal segment of leg 2 in the male. $Nitocra$ $vietnamensis$ n. sp. has the character combination of six setae on the ellipsoidal exopod of leg 5 in both sexes, the first endopodal segment of leg 1 shorter than the whole exopod, the seta/spine armature of an inner seta of P2-P4 enp-1 and four elements on P2 enp-3, and the reduction of the proximal endite to a seta on the maxillary syncoxa.

• Journal of Species Research
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• 제12권3호
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• pp.244-257
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• 2023

The family Ameiridae Boeck, 1865 (Copepoda; Harpacticoida) consists of about 380 species in 47 genera, but only 10 species have been reported in Korea. A benthic ameirid species was collected from the East Sea of Korea. Specimens were identified as members of the genus Ameiropsis Sars G.O., 1907, and this is the first record of the genus Ameiropsis in the Pacific Ocean. Ameiropsis gyeongjuensis sp. nov. is morphologically similar to A. mixta Sars G.O., 1907 and A. longicornis Sars G.O., 1907 from Norway. However, the new species is clearly distinguishable from the others based on the following morphological characteristics: the proximal segment of antennary exopod with a bulge in the middle, and with one pinnate seta; the distal segment of antennary exopod with a thickened, blade-shaped outer seta; and female P5 baseoendopod with five setae and exopod with six setae. An identification key to species is provided for the 11 valid species of the genus Ameiropsis.

• Journal of Photoscience
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• 제9권2호
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• pp.47-50
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• 2002

Raft is a distinctive membrane domain enriched in a certain class of lipids, cholesterol, and proteins observed on the plasma membrane. Growing evidence has revealed that such membrane domains play key roles in signal transduction, fertilization, development, transmitter release, and so on. Recently, we have isolated raft-like detergent-resistant membrane (DRM) fraction from bovine photoreceptor rod outer segments. Transducin and its effecter, cGMP-phosphodiesterase, elicited stimulus-dependent translocation between detergent-soluble membrane and DRM. This suggested potential importance of such distinct membrane domains in vertebrate phototransduction. Here, we will discuss physiological meaning of the translocation of major components of cGMP cascade to raft-like membrane in phototransduction. We would like to propose a hypothesis that raft-like membrane domains on the disk membrane are the place where cGMP cascade system could be quenched.

• 한국안전학회지
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• 제30권3호
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• pp.107-113
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• 2015

The goal of this paper is to investigate structural integrity factors of RMI(reflective metal insulation) to confirm the design requirements in nuclear power plant. Currently, a glass wool insulation is using now, but it will gradually be replaced with the reflective metal insulation maded by stainless steel plates. The main function of an insulation is to minimize a heat loss of vessel and pipes in RCS(reactor coolant system). It has to maintain structural a integrity in nuclear power plant life duration. In this study, the structural integrity analysis was carried out both multi-plate and outer shell plate by using a static analysis and experimental test. First, inner multi-plate has a self support structure for being air space. Because the effect of total static weight in multi-layer plate is low, a plate collapse possibility is not high. Considering optimum thin plate pressing process, it has to pre-check the basic physical properties. Second, the outer segment thickness and stiffener shape are verified by the numerical static analysis, and sample test for both type of panel and cylindrical pipe model.

• Journal of the Korean Wood Science and Technology
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• 제46권4호
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• pp.315-322
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• 2018

Bamboo culm comprises internodes and nodes and is tapered from the bottom to the top. Anatomically, bamboo culm comprises vascular bundles and parenchymal base tissue. The gross anatomical structure of a transverse section of any culm internode is determined by the shape, size, arrangement, and number of vascular bundles. The purpose of this research was to examine the morphology of culm and the distribution and shape of vascular bundles in Ampel bamboo (Bambusa vulgaris). Bamboo culms were harvested from the base. Test samples were obtained from a central 2-cm long segment of each internode across the entire length of the culm. Results showed an uneven spread of vascular bundles in the internode cross-section. Transitioning from the outer to the inner layer of the internode, the number of vascular bundles per unit area decreased and their shape was variable. The size of vascular bundles in the middle layer of the internode was greater than that of those in the outer and inner layers. The shape of vascular bundles was circular in the outer layer, which gradually transformed into vertical oval toward the middle layer and horizontal oval toward the inner layer. Vascular bundles were of type III and IV in the bottom of the culm and type III in the middle to the top of the culm.

• Journal of Welding and Joining
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• 제21권3호
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• pp.58-67
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• 2003

In this study, the formation mechanism of discontinuities in the laser fusion zone of diamond saw blade was investigated. $CO_2$ laser weldings were conducted along the butt between Fe base sintered tip and carbon steel shank with sets of variable welding parameters. The effect of heat input on irregular humps, outer cavity, inner cavity and bond strengh was evaluated. The optimum heat input to have a proper humps was in the range of 10.4~$17.6kJm_{-1}$. With increasing heat input, both outer and inner cavities were reduced. The outer cavity was caused by insufficient refill of keyhole, while inner cavity was caused by trapping of bubble in molten metal. The bubble came from sintered tip and intensive vaporization at bottom tip of the keyhole. A gas formation and low melting point element vaporization were not occurred during welding. We could not find any relationship between bond strength and amount of discontinuities. Because the fracture were occurred in not only sintered tip but also carbon steel shank due to hardness distributions.