• Korean Journal of Ichthyology
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• v.2 no.1
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• pp.47-52
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• 1990

Anew species of cyprinid fish Acheilognathus koreensis is described from specimens collected in several rivers of southern part of Korea. In general aspect it is similar to A. liηzbata but differs form this by having large snout length, narrow interorbital width and characters of early developmental stage. The new species is distinguished from A. signifer by color parttern of dorsal and anal fin ray in male, and egg form and ovipositor length in female.

• Journal of Mechanical Science and Technology
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• v.18 no.4
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• pp.718-730
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• 2004

The solution for the natural convection in internally finned horizontal annuli is obtained by using a numerical simulation of time-dependent and two-dimensional governing equations. The fins existing in annuli influence the flow pattern, temperature distribution and heat transfer rate. The variations of the On configuration suppress or accelerate the free convective effects compared to those of the smooth tubes. The effects of fin configuration, number of fins and ratio of annulus gap width to the inner cylinder radius on the fluid flow and heat transfer in annuli are demonstrated by the distribution of the velocity vector, isotherms and streamlines. The governing equations are solved efficiently by using a parallel implementation. The technique is adopted for reduction of the computation cost. The parallelization is performed with the domain decomposition technique and message passing between sub-domains on the basis of the MPI library. The results from parallel computation reveal in consistency with those of the sequential program. Moreover, the speed-up ratio shows linearity with the number of processor.

• Fisheries and Aquatic Sciences
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• v.19 no.2
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• pp.10.1-10.5
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• 2016

Setarches longimanus (Alcock 1894), in the family Scorpaenidae, was collected from Busan and the coastal waters of Jeju Island, Korea, in January and November 2014, respectively. Two specimens are characterized by XI, 10 dorsalfin rays; 19-21 pectoralfin rays; III, 5 anal fin rays; a second preopercular spine much shorter than the first and third; and an interorbital width 11.3 %-11.6 % of the standard length. We also analyzed 587 base pairs of the mitochondrial DNA cytochrome c oxidase subunit I sequences in order to confirm the taxonomic status of the specimen. As a result, the sequences of our specimen almost corresponded to those of Chinese S. longimanus (genetic distance, d = 0.005), but considerably differed from those of S. guentheri (d = 0.120-0.124). We propose the new Korean names "Ma-su-gam-peng-sok" for the genus Setarches, and "Bul-geun-ma-su-gam-peng" for the species S. longimanus.

• Journal of the Semiconductor & Display Technology
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• v.15 no.4
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• pp.79-85
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• 2016

For long life time and high efficiency, not necessary in improvement of LED chip structure, but also improve heat radiation for decrease heat in LED chip. In this study, efficiency decline factor has been investigated in LED lamp as study heat characteristic, luminance flux and heat resistance. When LED lamp temperature was increased, about 7% loss of luminance flux. In consequence of temperature analysis, width of fin was the most important factor of heat radiation. As a result, secure the enough heat path is very important factor of LED lamp design.

• Proceedings of the SAREK Conference
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• 2007.11a
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• pp.258-263
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• 2007

The performance of louver-finned flat-tube radiators for computer CPU liquid cooling were experimentally investigated. In this study, 5 samples of louver-finned flat-tube radiators with different width size (19mm, 24mm), tube hole (1, 9) and pass number (1, 2, 5) were tested in a wind tunnel. The experiments were conducted under the different air velocity ranging from 1 to 5 m/s. The water flow rate through a pass was 1.7 LPM. Inlet temperatures of air and water were $20^{\circ}C$ and $30^{\circ}C$ respectively. The results showed that the best performance in the 24mm sample considering pressure drop and heat transfer coefficient.

• Korean Journal of Ichthyology
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• v.17 no.1
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• pp.1-7
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• 2005

A new chub, Zacco koreanus sp. nov., is described on the basis of 104 specimens from six localities in Korea. The new species is distinguished from other Zacco species by the following characteristics: 9~10 scales above lateral line to dorsal fin origin, yellowish anterolateral side of body, no hemicircular red blotch on the upper margin of the eyes, reddish anterior margin of pectoral fin, larger orbit diameter and narrow interorbital width. The new species is widely distributed in the most streams of Korea, except the Yeongsan R., while Zacco temminckii is restricted in the Dongjin R., Yeongsan R., Seomjin R., Tamjin R. and Nakdong R. in Korea. When the two species occurred sympatrically in the same stream, Z. koreanus sp. nov. prefered mostly rapid lotic environments while Z. temminckii inhabited lentic ones. The Korean Z. temminckii was redescribed herein. A key to the Zacco species of Korea and Japan is provided.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.17 no.9
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• pp.2133-2138
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• 2013

In this paper, the variation of a steep subthreshold slope at elevated temperature in nanowire n-channel junctionless and inversion mode MuGFETs has been compared. It has been observed that the subthreshold slopes are increased with the increase of the operation temperature in junctionless and inversio-mode transistors. The variation of a subthreshold slope with operation temperature is more significant in junctionless transistor than inversion-mode transistor. The temperature dependence on the variation of a subthreshold slope for different fin widths shows a similar behavior regardless of fin width. From the temperature dependence on the variation of a subthreshold slope for different substrate biases, it has been observed that the variation of a subthreshold slope is less significant when the substrate bias was applied. It is worth noting that one can achieve a subthreshold slope of below 41mV/dec at elevated temperature of 400K using the junctionless MuGFETs with a positive substrate bias.

• Journal of Advanced Marine Engineering and Technology
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• v.33 no.8
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• pp.1137-1143
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• 2009

Experiments were conducted to evaluate pool boiling heat transfer performance between plain and micro finned surfaces with FC-72, which is chemically and electrically stable. Three kinds of micro fins with the dimension of $100{\mu}m\;{\times}\;10{\mu}m$, $150{\mu}m\;{\times}\;10{\mu}m$ and $200{\mu}m\;{\times}\;10{\mu}m$ (width $\times$ height) were fabricated on the surface of a silicon chip. The experiments were carried out on the liquid subcooling of 5, 10 and 15 K under the atmospheric condition. The micro finned surface with a larger fin width of $200{\mu}m$ provided a better pool boiling heat transfer performance. Also, the micro finned surfaces showed a sharp increase in heat flux with increasing wall superheat and a larger heat transfer enhancement compared to a plain surface.

• Korean Journal of Ichthyology
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• v.9 no.2
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• pp.169-173
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• 1997

First records of the two triglid fishes, Lepidotrigla hime and L. kishinouyei, are described on the basis of specimens collected from the South Sea of Korea. L. hime and L. kishinouyei are, closely similar to L. abyssalis and L. microptera in their proportional measurements, respectively. L. hime differs from L. abyssalis in having the rostral width broader than interorbital one, well developed spines of rostrum and long maxilla reaching to anterior margin of pupil. L kishinouyei differs from L. microptera in having a large and strong rostral spines and a jet black spot of pectoral fin inside.

• Animal Systematics, Evolution and Diversity
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• v.3 no.1
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• pp.41-50
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• 1987

The osteological characters of Aphyocypris chinensis of subfamily Leuciscinae were examined and the systematic position of this species is discussed through comparison with other species of subfamilies Leucisicinae and Cultrinae. Numbers of the dorsal an danal fin ray, having no symphyseal knob and barbels and separation between dermosphenotic and supraorbital, are in acord with those of subfamily Leuciscine, and the abdominal keel and trigemino-facial nerve foramen of the prootic are more closely related with those of subfamily Cultrinae. But several diagnostic characters detected only in this species are as follows ; 4 infraorbitals, the shape of ethmoid, 5-6 hypurals, the broad orbital width, having no extrascapular, incomplete lateral line and considerable small size.