• ALGAE
• /
• v.18 no.4
• /
• pp.361-363
• /
• 2003

This study was conducted at Seomjin River estuary to identify the causative species of algal bloom and their blooming cycles. Field surveys were conducted at 4 stations in every week from April to December of 1999. Thirty species were observed as the causative species of alga bloom. Skeletonema costatum, Thalassiosira sp., and microflagellate spp. (mixed red tide: Chroomonas sp. and two species of Prasinophycea) made algal blooms during the present study period. In addition, toxic algal species of diatom Pseudo-nitzschia multiseries and dinoflagellate Dinophysis acuminata were observed. The algal blooms were caused by microflagellate spp. in June, Thalassiosira sp. in July and Skeletonema costatum in August. Generally, the algal blooms persisted for about 5 days in this area.

• ALGAE
• /
• v.32 no.3
• /
• pp.181-187
• /
• 2017

During a sampling at Nokdong harbor, southern coast of Korea in January 2017, the marine diatom Coscinodiscus wailesii cells infected by a novel parasitoid nanoflagellate were observed. While the development process of the trophosomes of the parasitoid was more similar to that of Pseudopirsonia mucosa, division pattern of the auxosomes was similar to that of Pirsonia species. Phylogenetic analyses inferred from 18S rRNA gene sequences revealed that the parasitoid infecting C. wailesii fell within the cercozoan groups and branched as a sister lineage of the clade consisting of Pseudopirsonia mucosa and the undescribed Cercomonas sp. SIC7235, with the sequence dissimilarity of 7.3% with Pseudopirsonia mucosa. All of these developmental and molecular characteristics suggest that the parasitoid nanoflagellate infecting the diatom C. wailesii is a new Pseudopirsonia species.

• Fisheries and Aquatic Sciences
• /
• v.10 no.2
• /
• pp.68-73
• /
• 2007

Based on four juvenile specimens of Lutjanus collected from the southern coast of Jeju Island, three species, L. argentimaculatus, L. fulviflamma, and L. quinquelineatus, are described as the first record from Korea. The first species is easily differentiated from other lutjanid juveniles by distinct coloring of the dorsal, pelvic, and anal fins as well as two blue lines below the eye; the second species is characterized by having six yellowish brown stripes below the lateral line and a black spot on the side; the third species is identified by five longitudinal blue stripes and a black spot on the side when fresh. The new Korean names "Bul-geun-tung-dom," "Yuk-seon-jeomtung-dom," and "O-seon-tung-dom" are proposed for L. argentimaculatus, L. fulviflamma, and L. quinquelineatus, respectively.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2017.05a
• /
• pp.135-136
• /
• 2017

Oyster shell is produce by shucking process in oyster farming in southern coast of Korea. In average, about 6.7kg of oyster shell is produced as an industrial waste for 1kg of oyster flesh, and even only in last year, it is estimated that about 150,000 ton of oyster shell is produced. Oyster shell is light weighted and the strength characteristic of it is similar to send. So we produced mortar test piece using grounded oyster shell powder according to Filler and reviewed Fireproof Performance.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2016.10a
• /
• pp.58-59
• /
• 2016

Oyster shell is produced by shucking process in oyster farming in southern coast of Korea. In average, about 6.7kg of oyster shell is produced as an industrial waste for 1kg of oyster flesh, and even only in last year, it is estimated that about 150,000 ton of oyster shell is produced. Oyster shell is light weighted and its strength characteristic is similar to sand. So we produced mortar test piece using grounded oyster shell powder under 0.6mm, 0.6~1.2mm, 1.2~2.5mm, 2.5~5.0mm of its particle size according to fine aggregate standard and reviewed strength Properties.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2016.10a
• /
• pp.156-157
• /
• 2016

Oyster shell is produced by shucking process in oyster farming in southern coast of Korea. In average, about 6.7kg of oyster shell is produced as an industrial waste for 1kg of oyster flesh, and even only in last year, it is estimated that about 150,000 ton of oyster shell is produced. Oyster shell is light weighted and the strength characteristic of it is similar to sand. So we produced mortar test using different law of multiple proportions of grounded oyster shell powder of its particle size according to fine aggregate standard and reviewed strength Properties.

• 유체기계공업학회:학술대회논문집
• /
• 2005.12a
• /
• pp.813-818
• /
• 2005

Cooling seawater of thermal power plant which amounts about 5 cms per 100 MWe has hydro energy of about 3,000 kW at the thermal power plant complex, but this useful hydro energy has not been developed. Therefore, the feasibility study on hydro energy development of three power plants located in the southern and western coast of Korea was performed. Three target power plants are Samcheonpo, Boryeong and Hadong thermal power plant. The design head to discharge cooling water by gravity and the head caused by tidal level in the southwestern coastal area, could be used for the production of electric power. The various alternatives were studied and technical feasibility and economical efficiency were clearly proved.

• Fisheries and Aquatic Sciences
• /
• v.6 no.3
• /
• pp.135-139
• /
• 2003

During routine survey of Pacific oyster (Crassostrea gigas) collected from Tongyoung area in southern coast of Korea, histological examination revealed that a intracellular microorganisms infected the digestive gland of the oyster. They infected hepatopancreatic cells extensively. The size of intracellular microorganism was of 45 to 86nm in diameter and 200nm to more thar 500nm in length. They were pleomorphic. The morphological characteristic of intracellular microorganisms lacked cell wall and was bounded by the plasma membrane. They contained typical prokaryotic ribosomes and fibrillar DNA-like strands. No additional internal structure has been observed. Based on the lack of cell wall and the cellular localization, the intracellular microorganism is considered as a Mycoplasma-like organism.

• Fisheries and Aquatic Sciences
• /
• v.14 no.4
• /
• pp.421-428
• /
• 2011

We conducted modeling experiments to evaluate the residence times and exchange rates of seawater in Gamak Bay, located on the southern coast of the Korean Peninsula. The results revealed that pollutants are more quickly dispersed in a fixed grid rather than in a variable grid system. Pollutant concentrations decayed exponentially with time after release near the mouth of the bay, whereas no exponential variations were seen at the northwest end of the bay. The mean exchange rate of the seawater was 1.58% per day in the variable grid system, and the residence time of pollutants was greater than 288 days in Gamak Bay. Conversely, the exchange rate of seawater in Gamak Bay, as revealed by the particle tracking method, was 65% over a 50-day simulation. The results suggest that the seawater exchange in Gamak Bay is so low that pollutants are likely to remain in the bay indefinitely.

• Fisheries and Aquatic Sciences
• /
• v.16 no.4
• /
• pp.325-329
• /
• 2013

New occurrences in Korean waters were recorded for two penaeid species: Atypopenaeus stenodactylus (Stimpson, 1860) and Metapenaeopsis toloensis Hall, 1962, which were previously known from the Indo-West Pacific up to southern Japan. The specimens were collected from the southeastern coast of Korea by a shrimp beam trawl. The former is the only known member of the genus Atypopenaeus and the latter is the sixth species of the genus Metapenaeopsis reported in Korea. Morphological descriptions and illustrations with color photographs of the specimens are given. At present, the Korean Penaeidae consist of 20 species in 11 genera. A key to the Korean genera of family Penaeidae is also presented.