• Transactions of the Korean Society of Mechanical Engineers B
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• v.29 no.3 s.234
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• pp.295-305
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• 2005

To improve the aerodynamic effciency of TR-E2, a new configuration so called TR-E2Sl was introduced. TR-2251 is composed of different wing airfoil section and T-tail shape compared with TR-E2. Wind tunnel test for TR-EBS1 had been performed by changing the incidence angles of wing and deflection angles of control surfaces such as elevator and rudder. Also the on/off effect of ventral fin attached underneath of AFT fuselage was tested. Test result showed that variations of wing incidence angle did not cause any severe differences in aerodynamic characteristics. Longitudinal and directional characteristics of TR-E2S1 show stable for the pitch and yaw motions. However, the lateral stability of TR-E2S1 is not stable for a certain control surface deflection.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.26 no.5
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• pp.465-476
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• 1993

Rockfish, Sebastes inermis is a ovoviviparous fish distributed around the coastal waters of Korea and Japan. Naturally beared larvae obtained from female fish kept in the aquarium were reared for three months in the laboratory. The naturally healed larvae were 6.05mm in average total length(TL) with $8+18{\sim}19=26{\sim}27$ myomeres. Melanophores were distributed on the top of head, around the intestine tube and on the dorsal and ventral margins of the tail, but none on the pectoral fins. The larva(7.1mm in TL) consumed all the yolk and oil globule, in 7 days after bearing, and jaw bones were more rapidly ossified than vertebrae and cranium. In 21 days after bearing, the larvae averaged 8.50mm in TL and the caudal notochord flex $45^{\circ}$. Fin development in S. inermis larvae proceeds in the following sequence: caudal, pectoral, dorsal, anal and ventral fin. Individuals $17.6{\sim}20.8mm$ in TL($65{\sim}69$ days after bearing) are regarded as the juvenile stage. All fins bones was nearly completed in this stage.

• Korean Journal of Ichthyology
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• v.9 no.2
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• pp.186-194
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• 1997

Naturally beared larvae obtained from female fish kept in the aquarium were reared for 45 days in the laboratory. The naturally beared larvae were 3.19 mm in average total length (TL) with 9+15~16=24~25 myomeres. Melanophores were distributed on the dorsal margin of intestine tube, ventral margins of the tail and around the oil globule, but none on the top of head and on the pectoral fins. The larva (3.35 mm TL) consumed all yolk and oil globule in 5 days after bearing, and jaw bones and clavicle began to be ossified rapidly. In 22 days after bearing, the larvae averaged 6.30 mm TL and the caudal notochord flex $45^{\circ}C$. Fin development in S. marmoratus larvae proceeds in the following sequence : caudal, pectoral, dorsal, anal and ventral fin.

• Journal of Aquaculture
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• v.12 no.1
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• pp.15-24
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• 1999

From January 1997 to May, the red marbled rockfish, Sebastiscus tertius (Barsukov et Chen) was reared in the laboratory, and observed the morphological characteristies of egg and development of larvae and juveniles. The egg is spherical in shape colorless and transparent, measuring 0.72~0.80mm in diameter (mean 0.75mm, n=50). The naturally bearing larvae were 3.79~3.97mm in total length with 7~8＋15~16=22~24 myomeres, and mouth and anus were open. Melanophores were present on the yolk of the larva and ventral margins of the tail. The 1~2 days after bearing larvae measured 3.90~4.13mm in total length, and transformed to postlarval stage, and yolk sac were completely resorbed. On the lower jaw melanophores were present. Total length of the larvae was 4.23~4.60mm in total length (11 days after bearing), number of elongated pectoral fin rays was 9~10, and melanophores distributed on the top of head, around the intestine tube, ventral margins of the tail and on the pectoral fin. In 21 days after bearing, the larva were 5.83~7.10mm in total length, and the caudal notochord flex $45^{\circ}$. Individuals of 9.80~12.36mm in total length (33 days after bearing) are regarded to have reached to the juvenile stage with all the fins were developed.

• Development and Reproduction
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• v.22 no.1
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• pp.39-53
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• 2018

The purpose of this study is to investigate the early life history of the Rhodeus fish, Rhodeus uyekii and R. ocellatus, in the Nakdong River to use as the preliminary data for the systematic study. The embryos used in the study were fertilized eggs (embryo) and larvae after artificial fertilization. The long diameter of the eggs of the R. uyekii was 3.39-3.97 mm (average $3.68{\pm}0.41mm$, n=30) and the short diameter was 1.36-1.55 mm (average $1.45{\pm}0.13mm$, n=30). The long diameter of the eggs of the R. ocellatus was 2.53-2.71 mm (average $2.62{\pm}0.12mm$, n=30) and the short diameter was 1.47-1.60 mm (average $1.53{\pm}0.09mm$, n=30). Hatching time was 48 hours for the R. uyekii and 50 hours for the R. ocellatus given that the average water temperature was $21.5^{\circ}C$. The hatched larvae were 4.95-5.00 mm (average $4.98{\pm}0.04mm$, n=5) for the R. uyekii and the total length was 3.66-3.69 mm (average $3.67{\pm}0.02mm$, n=5) for the R. ocellatus. R. uyekii was found to be 15.5-15.8 mm at total length (average $15.6{\pm}0.21mm$, n=5) on the 56 days after hatching with the number of dorsal fins being ⅲ-9, anal fins ⅲ-10, ventral fins ⅲ-5. The R. ocellatus was found to be 15.8-16.0 mm (average $15.9{\pm}0.14mm$, n=5) at total length on the 58 days with the number of dorsal fins being ⅲ-11, anal fins ⅲ-12 and ventral fins ⅲ-5 where the number of all fin stalks reached maximum.

• Korean Journal of Ichthyology
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• v.13 no.1
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• pp.69-73
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• 2001

Observation of morphological changes during larval and juvenile stages of the halfbeak fish, Hyporhampus sajori (Temminck et Schlegel), was made based on samples of fertilized eggs collected on the shores of Youngil Bay, Phohang-shi, Korea, on May 27, 1991, and incubated in the laboratory. During the incubation period, water temperature fluctuated between $17.6^{\circ}C$ and $23.2^{\circ}C$. The newly hatched larvae were elongated and 7.0~8.50 mm in total length (TL) with 40~42+17~18 = 59~60 myotomes. Numerous melanophores were on the head, mid-dorsal part of the body, intestine, and the tail part of the notochord. Three days after hatching the larvae had attained 8.60~10.90 m in TL, had completely absorbed the yolk, and the caudal notochord was flexed $45^{\circ}$ upward. At this time, it was attained postlarvae stage. Thirty-seven days after hatching the postlarvae were 32.37~44.95 mm in TL and had reached the juvenile stage. All fins were formed with a complete set of fin rays with the following counts: dorsal fin rays 16~17; pectoral f in rays 6; ventral fin rays 12~14; caudal fin rays 11~12+11~12 = 22~24.

• Korean Journal of Ichthyology
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• v.4 no.2
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• pp.31-43
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• 1992

The blenniid fish, Entomacrodus stellifer light(Herre) is distributed in the coastal waters of southern Japan and south-eastern Korea. Matured adults of blenniid fish were collected from the rocky shore of Namchun-dong, Nam-gu, Pusan, Korea in July, 1991. The observations were made on the morphology and skeletal development of the reared larvae and juveniles. The lavae reached 5.80mm in mean total length(MTL) in 10 days after hatching. A this time the larvae have absorbed the yolk completely and became postlarvae. Melanophores are distributed on the fin membrane of the lower part of pectoral fin and ventral margins of tail. The larvae averaged 6.20mm in TL and the caudal notochord flex at $45^{\circ}$ in 13 days after hatching. The part of the fin-fold of the future dorsal and anal fins became high. The lavae reached juvenile stage in 31 days after hatching and attained 15.80mm in MTL, and all fin-rays was formed. Ossification of the cranium took place at 6.20mm of MTL(11 days after hatching) in parasphenoid. Vertebrae began to develop from the anterior end to ossify posteriorly. Ossification of all bones nearly completed when the larvae reached to 15.80mm in MTL (31 days after hatching).

• Development and Reproduction
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• v.18 no.3
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• pp.173-178
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• 2014

In order to monitor the developmental features of embryos, larvae, and juveniles of Oryzias latipes (Temminck and Schlegel), Oryzias latipes was caught in river of Shinduck-dong, Yeosu-si, Jeollanam-do, on May 2011, and experiments were carried out in Ichthyology laboratory at Chonnam National University. The blastodisc step was the first level for natural spawning. The optic vesicle, Kupffer's vesicle, myotome began to appear 75 hours 57 minutes later. After blastodisc development, the pectoral fins were made at 143 hours 37 minutes and the tail was separated started at the same time. Hatching was observed at 167 hours 27 minutes after blastodisc. The total length of the hatched larvae was 4.95~5.10 mm (mean, 5.01 mm), the mouth and anus were opened. Larvae used yolk completely after 3 days after hatching. The total length larvae was 5.45~5.56 mm (mean, 5.52 mm) after 8 days after hatching, and appeared the stems for tail. The stems pectoral, anal fin were showed after 14 days and the stems dorsal, ventral fin were appeared after 19 days. For 35 days after hatching, the total length of larvae 13.95~15.30 mm (mean, 14.64 mm), and at this time, fins and body were transferred like the adult Oryzias latipes.

• Journal of fish pathology
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• v.16 no.1
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• pp.13-21
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• 2003

The infection characteristics with scuticociliates at on-land rearing farms and hatcheries of flounder, Paralithys olivaceus was investigated during the year of 2001 by juvenile infection routes. When culture tanks for living food organisms such as chlorella, rotifer, and Artemia were searched, scuticocilates were detected both in live and dead rotifer, and at the dregs of culture tank bottoms at almost hatcheries. When rotifer infected with scuticocilates fed on fish larvae, lots of scuticocilate were inhabited at the bottom of fry rearing tanks. After feeding on scuticocilates-infected rotifer on fish larvae, first infection was detected at 10 days after bottom dwelling or 40 days old after hatching. By histopathological examination we confirmed the infection route of eyeball or brain contamination was that the ciliate worms digged through mouth and front part of the dosal fin cuticle, transferred into eyeball along the epithelium and muscle tissue, and reached finally into brain by the muscle and nerve tissue. The infection of internal organs was clarified into two routes. The first route was started from the infection at ventral and anal fin rays by the worms, and reached at the anus and rectum through the epithelium and muscle tissue. The second route was initiated from the infection at urinary organ and reached into the rectum epithelium cells, inner wall of intestine, abdominal cavity, pancreas, kidney, and pancreas. At seed production farms where fish larvae fed on scuticocilate-free rotifer, the worms were not detected not only at the food organisms culture tanks and juvenile rearing tanks but also larval flounder less than 7cm in total length.

• Animal Systematics, Evolution and Diversity
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• v.9 no.1
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• pp.51-59
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• 1993

A gobiid fish, Parioglossus dotui Tomiyama is described from 359 specimens collected at Cheju-do and Pusan, in August 1994 of 1986. This is the first definitive record of the species in the Korean waters. Parioglossus dotui having a small-sized body usually is found swimming in schools. The branchiostegals are 5 in number on each side. It grows up to 40mm in total length. Most of ventral fins are separated and connected with rudimentray membrane. In this species, the lateral line were indistincet or absent. The caudal fin slightly emarginates or truncates in both sexes, with a dark spot at the border of the base. It Inhabits inlet waters and estuaries of rivers. "Deungsul mang-dug" is proposed as Korean name of this species.