• Korean Journal of Ichthyology
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• v.13 no.3
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• pp.201-209
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• 2001

Annual reproductive cycle of seabass, Lateolabrax japonicus, was histologically investigated based on samples captured on the coast of the Tongyoung, South Korea. The gonadosomatic index (GSI) of females began to increase in October and reached its maximum in February. The GSI of males reached its maximum in December. The change of GSI and gonadal tissue showed that the annual reproductive cycle was classified into the following successive four stages: (1) the degenerative and resting stage from March to August, (2) the growth stage from September to November, (3) the mature stage from November to December, and (4) the ripe and spawning stage from December to March.

• Ocean and Polar Research
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• v.23 no.3
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• pp.285-290
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• 2001

The strength of juvenile black rockfish, Sebastes schlegeli, raised in different hatcheries for wild stock enhancement was evaluated in terms of resistance to an anesthetizing agent, tricaine methane-sulfonate (MS-222), and exposure to drying. The working dosage of MS-222 varied significantly with fish size and hatchery population. Smaller fish were less resistant to the chemical than larger ones. MS-222 effects also differed with fish growth history. The fish cultured in embanked populations showed stronger resistance, earlier recovery, and lower mortality, compared to those cultured in land-based tanks or collected from wild stocks. Similar results were seen in juveniles challenged to dry exposure. These results suggest that an embanked population of black rockfish is more resistant to anesthetic stress, expressed as anesthesia recovery and mortality, and that this population is healthier than others.

• 한국정보디스플레이학회:학술대회논문집
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• 2008.10a
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• pp.1049-1052
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• 2008

We developed novel molecular dynamics and quantum chemical molecular dynamics simulators for the design of MgO protecting layer in plasma display panel. These simulators were applied to the investigations on the destruction processes of the MgO protecting layer as well as the evaluation of its second electron emission ability. From the simulation results, we successfully proposed new guidelines for MgO protecting layer with high durability and high second electron emission ability.

• 한국정보디스플레이학회:학술대회논문집
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• 2006.08a
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• pp.121-124
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• 2006

A novel quantum chemical molecular dynamics program, 'Colors' was developed to simulate the electronic structure of rare earth-doped phosphor materials as well as the destruction processes of MgO protecting layer in plasma display panel (PDP). We have also developed a quantitative prediction method based on Monte Carlo simulation technique to evaluate the electrical conductivity of insulators, semiconductors, and metals as well as the spatial distribution of electron density by Colors code. All these original simulators enable us to study theoretically a variety of materials related to PDP.

• ALGAE
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• v.17 no.2
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• pp.117-125
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• 2002

Five microalgal species isolated from the Jeju coast and four microalgal stock strains in hatchery were cultured in order to investigate their adapation to extreme changes in environmental factors such as salinity, water temperatue, adn nutrients. In case of salinity variation, Nitzschia sp. of Bacillariophyceae, Isochrysis galbana of Haptophyceae and Tetraselmis gracilis of Prasinophyceae showed optimum growth at the low salinity of 20 and 25 psu. Amphora coffeaeformis and Chetoceros simplex of Bacillariophyceae, and Pavlova lutheri of Haptophyceae adapted well at the relatively high salinities of 30 and 35 psu. However Phaeodactylum tricornutum of Bacillariophyceae and Chlorella sp. of Chlorophyceae showed euryhaline property In case of water temperature variation, most of all the species studied wer inhibited at 10℃. C. simplex, Nitzschia sp., p. tricornutum, Chlorella sp. and T. gracilis grew well at above 20℃. A. coffeaeformis, I. galbana and P. lutheri adapted also at the high temperature of 30℃. Each microalgal strain showed different growth rates and its maximum biomass. Generally microalgal populations from the Jeju coast grow well in relatively high salinity and high water temperature. Their growth were inhibited at low water temperature, but not likely affected at low salinity. This study indicates that the microalgal populations could not be affected by abnormally low salinity phenomena, which have happened occasionally around the west Jeju coast in summer and have led macrobenthic animals to mass mortality.

• Fisheries and Aquatic Sciences
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• v.23 no.5
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• pp.13.1-13.7
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• 2020

Stock enhancement is considered to be a valuable approach for restoring fishery resources. Because no specific official institution in Taiwan is responsible for the production of fry, the released fry are purchased directly from the private sector. However, fishermen from the private industry have not established a genetic background, so the genetic composition for each batch of released fry is unclear. Mangrove red snapper (Lutjanus argentimaculatus), a prominent species released in Taiwan, was collected after its official release. One hundred and two field samples were compared with four batches of hatchery fry (n = 685) by using a microsatellite-based multiplex PCR assay. Four of the field samples (3.9%; 4/102) were revealed to be from a fish farm and most likely from a single batch. This study revealed that wild mangrove red snappers are genetically different from those originating from farms, and their origins can be traced through molecular markers, even without information on breeding stocks.

• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.169-172
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• 2009

We developed ultra-accelerated quantum chemical molecular dynamics and characterization simulators for study and design of plasma display panel (PDP) related materials. By use of these simulators, realistic structure of PDP materials is drawn on the computer. Furthermore, based on the structures, various properties such as secondary electron emission coefficient are successfully evaluated. In this report, we will discuss the theoretical secondary electron emission coefficient for several protecting layer materials and the effect of surface structure on the properties based on the result of atomistic simulations.

• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.294-297
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• 2009

We computationally investigated the effects of oxygen and alkaline-earth on the emission wavelength of the $Eu^{2+}$-doped oxide phosphor. Using QSPR method, we found that the oxygen and alkaline-earth atom around the Eu atom increase and decrease the emission wavelength, respectively. We also investigated the $Eu^{2+}$-doped sulfide, nitride, and oxynitride phosphors.

• Journal of Aquaculture
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• v.10 no.4
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• pp.403-407
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• 1997

Intraspecific sequence variation was detected by polymerase chain reaction (PCR) and direct sequencing of a 350-nucleotide region of the mitochondrial 12S rRNA gene of two natural populations (Han River and Nakdong River) and one hatchery stock (Jinhae Inland Fisheries Institute) of local strain common carp, one Israeli strain of common carp stock from Pukyong National University (PKU), and one hybrid between Israeli strain of common carp female and local strain common carp male from PKU stock. There is little variation in 350 bases of the mitochondrial 12S rRNA gene sequences among 2 natural and 1 hatchery local strain common carp populatins, representing abut 7 to 20 nucleotide differences (less than 6%). The sequence of specimens from Han River was more similar to that from Nakdong River (identity=98.0%) than to that from Jinhae Inland Fisheries Institute (identity=96.3%). Sequence variation between Israeli strain and wild local strain common carp was higher than the variation within natural stocks. The level of variation was ranged from 15.7 to 17.7%. The hybrid showed very similar nucleotide4 sequence of 12S rRNA gene to the sequence of Israeli strain with the identity of 98.9%.

• Animal Bioscience
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• v.35 no.4
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• pp.631-637
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• 2022

Objective: Surface disinfection is important in the proper running of livestock farms. However, disinfection of farm equipment and facilities is difficult because they are made of different materials, besides having large surface areas and complex structures. 3-(trimethoxysilyl)-propyldimethyloctadecyl ammonium chloride (Si-QAC) is a quaternary ammonium salt-based disinfectant that attaches to various surfaces by forming covalent bonds and maintains its disinfecting capacity for a considerable time. Our aim was to evaluate the potential use of Si-QAC for disinfection of farm equipment and facilities. Methods: The short- and long-term antimicrobial and antiviral effects of Si-QAC were evaluated in both laboratory and farm settings using modified quantitative assessment method based on the standard operating procedures of the United States Environmental Protection Agency. Results: Si-QAC was highly effective in controlling the growth of the Newcastle disease virus and avian pathogenic Escherichia coli. Electron microscopy revealed that the mechanism underlying the disinfection activity of Si-QAC was associated with its ability to damage the outer membrane of the pathogen cells. In the field test, Si-QAC effectively reduced viral contamination of surfaces of equipment and space. Conclusion: Our results suggest that Si-QAC has great potential as an effective chemical for disinfecting farm equipment and facilities. This disinfectant could retain its disinfection ability longer than other commercial disinfectants and contribute to better farm biosecurity.