• Korean Journal of Ichthyology
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• v.12 no.2
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• pp.137-145
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• 2000

The embryonic and larval development of Chelon lauvergnii (Eydoux & Souleyet) was surveyed by incubating artificially inseminated eggs with parent fishes obtained at Kang-wha island in the mid-western coastal area of Korea on June, 1997. The fertilized eggs were transparent, spherical in shape, measuring 0.95~1.08 mm in diameter, having a large oil globule, and their perivitelline space narrow, and began to hatch at 40 hrs. in water temperature $22{\pm}1^{\circ}C$. The newly hatched larvae were 2.35~2.68 mm in total length with 23 myomeres, anus opened, mouth closed, preanal length 58.7~61.6% of total length, oil globule located in posterior end of yolk sac. Melanophores, branch in shape, were distributed mainly along the ventro-lateral region of trunk part and a few on the anterior end of caudal part and surface of oil globule. The larvae measuring 3.08~3.36 mm in total length absorbed yolk material completely in 3 days after hatching, in which air bladder began to appear and mouth opened. In 8 days after hatching, the larva was measured 5.09 mm in total length, its posterior end of notochord began to flex upward and the caudal fin rays differentiated as 7, finfold of the second dorsal and anal fins appeared. In this time, melanophores, branch in shape, were concentrated in the anterior half region of the caudal part and a few also distributed on the top of head, snout region, ventral margin of lower jaw and isthmus region. In 12 days after hatching, the larva measuring 8.48 mm in total length completed all the fins (D. IV-9; P1. 16; P2. I, 5; A. II, 9) and reached to the juvenile stage. Melanophores, in this time, were distributed on the mid-lateral region of the caudal part in enlargment than before and a few also found in the dorso-lateral region of the trunk part, and in the cheek region.

• Korean Journal of Ichthyology
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• v.12 no.2
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• pp.129-136
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• 2000

The aucha perch, Coreoperca kawamebari was collected in Tam-jin river from February to June 1998. It was reared in the laboratory and observed the spawning behavior and early life history. Spawning season was from mid of April to the end of May in the Tam-jin river. The fertilized eggs were demersal of adhesive, transparent and spherical in shape. Egg diameter was 2.21~2.65 mm with several oil globule of 0.058~0.343 mm. Hatching occurred about 194 hours 23 minutes after fertilization at water temperature of $18{\sim}22^{\circ}C$. Newly-hatched larvae were 5.09~5.68 mm in total length(TL, mean: 5.38mm) with 10~11+18=28~29 myotomes and opened mouth and anus. Melanophores were distributed on the eye lens, on the head, around the yolk, on the dorsal part and the abdominal region of the trunk. After hatching 5 days larvae attained 6.12~6.68 mm in TL (mean: 6.47 mm), and the yolk sac was completely absorbed and transformed to postlarva stage. The larvae reached to the juvenile stage with all the fins were formed with complete set of fin rays (D. XII-12~13; A. III-8~10; P. 11~13; V. I-4~5) at the 22 days after hatching and of the larvae was 11.54 mm in total length. In 32 days after hatching, the juvenile was 13.05 mm in TL. This period was similar to adult in body form and the spot.

• Korean Journal of Ichthyology
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• v.24 no.3
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• pp.160-166
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• 2012

Egg development and early life history of the endangered Korean freshwater fish, Microphysogobio koreensis, was investigated to get a basic information for establishing its conservation strategy. The matured adult fishes were sampled at Imsil-gun, Jeollabuk-do, Korea in May 1 2012 and artificially fertilized. The fertilized eggs were spherical, separated demersal and $1.8{\pm}0.14mm$ in diameter. The hatching of the embryo began at about 29 hours after fertilization under water temperature of $23^{\circ}C$. The newly hatched pre-larvae were average $2.2{\pm}0.48mm$ in total length. At 4 days after hatching, the post-larvae were $3.6{\pm}0.55mm$ in total length and york sac was completely absorbed. At 20 days after hatching, their fin rays were formed and finally the larvae entered juvenile stage and grew up to $6.5{\pm}0.77mm$ in total length. At 60 days after hatching, the total length reached $24.4{\pm}1.71mm$, and the band patterns of he head and lateral side were similar to adult fish. Based on this study, the fertilized eggs of M. koreensis hatched more quickly and the pre-larvae length was also smaller, compared with related species.

• Korean Journal of Ichthyology
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• v.13 no.3
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• pp.166-172
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• 2001

Parental care of eggs of Chromis fumea (Tanaka) was observed by Skin Scuba gear in August 1995 off Cheju Island. The eggs and larval development were observed in the laboratory at Pukyong National University, Pusan. Eggs were deposited on a flat surface of hard substratum and formed a plain sheet of one layer of eggs. Males showed parental care of the eggs by hovering over the nest and attacking other fishes that approached the nest. The spawned eggs were transparent, elliptical in shape and measured 0.73~0.88 mm in long axis and 0.50~0.56 mm in short axis. An analysis by T-test of the long axis of the egg with time showed a significant difference (p<0.01). However, there was no significant difference in short axis with time. Eggs were reared at water temperatures of $23.0{\sim}25.5^{\circ}C$ and took about 4~5 days from embryonic body stage to hatching. The newly hatched larvae were 1.10~1.61 mm in notochord length (NL) had 21 myomeres, has closed mouth but open anus, preanus length was 45.8% of NL. Melanophores were distributed on the occipital region of head, the eye, the peritoneal region, and along the ventral contour. The larvae absorbed the yolk material and oil globule in 3~4 days after hatching and became postlarvae. On the third day after hatching, the larvae had attained 1.9~2.4 mm in NL, had 25 myomeres, and showed rapid growth. By the ninth day after hatching, the larvae had attained 2.9 mm in NL, had an swimbladder in the dorsal margin of ventral region, the preanus length was 37.9% of NL, and their melanophores were enlarged and reduced in number.

• Korean Journal of Ichthyology
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• v.13 no.3
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• pp.161-165
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• 2001

Artificial fertilization (dry method) of mature right-eye flounder, Limanda yokohamae (female : 25.1~30.4 cm in total length (TL), male : 24.5~28.5 cm in TL), obtained from the fish market in Dolsan-do, Yosu was performed in the Fisheries Exhibition. Hatched larvae and juveniles were reared to describe their morphological development. Newly hached larvae attained 3.13~3.42 mm in TL. Their eyes were yellowish brown and their mouth and anus were not yet opened. Three to six days after hatching the larvae attained 3.35~4.61 mm in TL. Their mouth and anus were open and the yolk sac was almost absorbed. Feeding activity increased as the mouth became larger. At 25 days, the larvae attained 5.47~5.91 mm in TL. The caudal notocord was flexed $45^{\circ}$ upward. At 35 days, the larvae attained 6.83~7.60 mm in TL. Rays of the dorsal and anal fins were formed, and the left eye was moved slightly to the right side of the head. At 55 days, the juveniles attained 9.38~11.73 mm in TL. The left eye was moved completely onto the right side. All of the fins had complete set of the fin rays, and the juveniles spent most of the time on the bottom resting on their blind side (D. 68~70 : A. 50~52 : P. 11: V. 6 : C. 18~19).

• Korean Journal of Ichthyology
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• v.19 no.4
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• pp.343-349
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• 2007

Embryonic and larval developments on Pacific cod, Gadus macrocephalus are described from laboratory-reared specimens. The eggs (1.075~1.168 mm in diameter) were weakly adhesive, almost spherical in shape, transparent and unpigmented, showing a pale yellow yolk without oil globules. Hatching was occurred 220 hrs after fertilization at $9.8^{\circ}C$. The newly hatched larvae (3.72~4.40 mm in total length, TL) had 43~47 (11~13+32~34) myomeres, mouth and anus which was not yet opened. The yolk was completely absorbed at 4.58 mm TL, and transformed to postlarval stage. Locations of the anus and second dorsal fin origin, and distinctive growth of the larvae head were observed at 5.48 mm TL with melanophores in the gill cover and upper region of the occipital. In addition, melanophores were distinctive in the ventral region and caudal fin base at 6.88 mm TL. All fins were formed with a complete set of fin rays having the following counts (D. 3~7-12~14-13~14; A. 13-15) at 11.54 mm TL. Both lateral line and barbel of lower jaw were observed at 15.07 mm TL.

• Development and Reproduction
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• v.10 no.1
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• pp.47-54
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• 2006

The Tridentiger obscurus were collected of Ocheon-dong and Dolsan-do in Yeosu from Apirl to July 2003, and were carried to the laboratory to investigate their development of spawning habit, egg development, larvae and juveniles. The fertilized eggs were measured $0.86{\sim}1.07{\times}0.53{\sim}0.74\;mm$ in diameter. Hatching of the embryo began about 154 hrs 40 mins after fertilization in water temperature of $18.4{\sim}23.2^{\circ}C$(mean $21.2^{\circ}C$). The newly-hatched larvae were $2.72{\sim}2.87mm$(mean 2.83mm) in total length (TL), their mouth and anus were opened, and the yolk sac was completely absorbed. At 21 days after hatching, the postlarvae were $5.32{\sim}7.23mm$(mean 6.02mm) TL, and the tip of the caudal notochord was flexed $45^{\circ}$ upward. The juveniles stage was reached when all fin-rays were formed at 45 day after hatching, and $11.62{\sim}14.32mm$(mean 13.45mm) TL.

• Journal of Korean Society of Transportation
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• v.24 no.6 s.92
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• pp.7-19
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• 2006

Due to the continuous expansion of the highway, the opening of the high-speed railway(KTX), etc, the demands of domestic air transport decreasing. In the circumstances, airports and local governments are spending themselves in taking a measure to activate local airports. In this aspect, this study seeks the smooth flow of human movement through the activation of Daegu International Airport by analyzing the present condition of Daegu International Airport in relation to the appearance of the high-speed railway, deducing plans for activating airports, and presenting the roadmaps for long-, mid- and short-term roles for the development of Daegu Airport, and Presents substantial fulfilling plans to secure the competitive power of Daegu International Airport by speeding up the flow of air goods of the area for the long run. It is suggested in the study that by setting up an organization exclusively responsible for activating Daegu International Airport in the city of Daegu, supporting local travel agencies to promote consistent demands, supporting aviation companies to employ Daegu International Airport as a major air base, establishing airlines with priority for airports that open newly in local cities of Japan and establishing and expanding airlines in China areas be promoted actively. Ministry of Construction & Transportation makes it a means of main airport Policy to only support Incheon International Airport to be a hub. However not only Incheon International Airport should be an amok representing the country, but also the wide Metropolitan area should supply the demands, and airports based in the West and East Coast areas need to be developed in the future. It is suggested that since air demands of domestic local airports are based on the demands of the of gin destination in neighboring region, multiple bases need to be developed. It is suggested that by developing not 1 in mega hub (Incheon International Airport) but 1 in mega hub. 2 in regional hub (the West and East Coast) and Jeju foy the tourism hub in our developing airports system.

• Applied Biological Chemistry
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• v.20 no.2
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• pp.236-241
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• 1977

Analytical method of carbofuran (2,3-dihydro-2, 2-dimethyl-7-benzofuranyl methyl carbamate) residues and its persistence in rice seeds, rice seedlings, rice plants and soils were studied by gas-liquid chromatographic analysis using electron capture detector. 1. The effective column material for clean-up is Florisil (5% $H_2O$)+Alumina (4% $H_2O$)+absorbent mixture with rinsing the first 300l of eluants to remove impurities in the column materials. 2. The method of applying an gelatin encapsulated carbofuran to the root zone of rice plant is the longest persistence in its residues. 3. By seed treatment, no carbofuran residues were detected in rice seeds and seedlings. 4. The amounts of carbofuran residues in rice seedlings is in proportion to the soaking time of rice seedlings in carbofuran solution rather than the concentration of the chemical. 5. Applying carbofuran by root zone has the higher and the loger residual effect than broadcast. 6. Persistence of carbofuran in the high clay content soil is longer than in the low clay content soil. 7. No carbofuran residue was detected in rough rice at havesting time.

• Korean Journal of Ichthyology
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• v.23 no.3
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• pp.198-205
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• 2011

Early life history of the endangered species, Gobiobotia macrocephala was investigated to provide baseline data for biological characteristics and recovery. Adult fish were sampled by spoon net at Hongcheon-gun, Gangwon-do, Korea in April to June 2010. The female's eggs were obtained by injecting Ovaprim and fertilized by dry method in the laboratory. The mature eggs were slightly adhesive and transparent with greyish and average 0.89${\pm}$0.04mm in diameter. The hatching of the embryo took place in about 107 hours after fertilization under water temperature of 23$^{\circ}C$ and newly hatched larvae were average 4.6${\pm}$0.16mm in total length. At 4 days after hatching, they were average 6.1${\pm}$0.20mm in total length and their yolk sacs were completely absorbed. From 15 days after hatching, they entered the juvenile stage and reached at 8.6${\pm}$0.67mm in total length. At the 100 days after hatching, their band patterns and external form were similar to those of adults, and they averaged 31.5${\pm}$3.32mm in total length.