• Korean Journal of Fisheries and Aquatic Sciences
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• v.31 no.6
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• pp.852-858
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• 1998

We have isolated a bacterial strain that tends to kill P. micans from the mixed culture of p. minns plus seawater filtrate (poresize, 0.8 $\mu$m) collected at Masan bay in July 1996, in which the mixed culture grown in the f/2 medium. According to the experimental results of the isolated bacterium such as fatty acids analysis, morphological and biochemical characteristic tests, the strain was supposed to be a Pseudomonas and then it was named as Pseudomonas sp. LG-2. The killing effect of Pseudomonas sp. LG-2 against P. micans was proportionally increased with the concentrations of culture filtrate (pore size, 0.8 $\mu$m) is well as with the number of bacterium inoculated. In the mixed culture inoculated with $1.3\times10^6$ cells/ml of Pseudomonas sp. LG-2, the number of P. micans (2,000 cells/ml) was gradually decreased and then killed below 100 cells/ml within 7 days. In addition, the culture filtrate with $30\%$ of final concentration revealed a significant killing effect against P. micans around 3 days after culture. In the relationship between killing effects and growth stage of Pseudomonas sp. LG-2, the culture filtrate at lag phase has little effects on P. micans. In constant, the culture filtrate at mid-log phase showed the killing effect by decreasing P. micans to 112 in number within 5 days. In particular, the culture filtrate at stationary phase showed a significant killing effect against P. micans in which the majority of it was killed after 3 day culture. The species specificity of killing effects of Pseudomonas sp. LG-2 against 5 species of dinoflagellate was only found in P. micans and Scrippsiella trochoidea.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.2 no.2
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• pp.155-160
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• 1969

The soil textures and chemical compositions of Tapes Philippinarum beds were investigated in order to estimate the grade of the habitat soil of T. Philippinarum for the improvement of natural tidal flats. The coefficients of correlation between tile percentages of debris, coarse sand, fine sand, silt, and clay of the habitat soil, and the population density of T. Philippinarum were 0.78, 0.73, -0.42, -0.68, and -0.51 respectively. And the optimum levels of same were above $13.5\%,\;above\;23.0\%\;below\;41.5\%,\;below\;10.0\%$, and below $6.8\%$ respectively The $SiO_2\;Al_2O_3+Fe_2O_3$ ratio of the soil of T. Philippinarum beds showed the range of 5.09 to 5.60. The levels of soil pH, water holding capacity, organic matter, total nitrogen, available phosphorus, exchangeable magnesium were 6.15-6.60, $4.26-6.86\%$, $0.40-1.10\%$ 14.0-27.0 ppm, $0.041-0.394\%,\;and\;0.009-0.132\%$ respectively.

• Korean Journal of Food Science and Technology
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• v.27 no.2
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• pp.185-192
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• 1995

Microbial and chemical changes of salt-fermented youbsak which is a traditional processed fish product only manufactured in Hampyung bay region were investigated in this study. Total microbial cells of salt-fermented youbsak was gradually increased up to 30 days fermentation and then it was decreased. The pH and total acidities of fermented youbsak were not greatly changed, except for a rapid decrease in pH and acidity after 15 days fermentation. Volatile basic nitrogen and amino-type nitrogen were rapidly increased until 30 days fermentation and then slightly decreased by adding the extracted soup of pig bones. Palmitic acid was the most abundant fatty acid, and the major free amino acids in salt-fermented youbsak were composed of leucine, tyrosine, glutamic acid, valine, isoleucine, alanine and methionine.

• Economic and Environmental Geology
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• v.51 no.1
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• pp.49-65
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• 2018

The lime-soil mixture on tomb barrier (LSMB) is a type of tomb in Joseon Dynasty, which made with so-called 'Sammul' (three material compound) that mixture of lime, fine sand and yellow ocher. This study divided the tombs of the Gungri Site from Joseon Dynasty with layered wall and integrated wall according to the manufacturing types, and investigated on the basis of analysis to material characteristics and making techniques. Analytical samples were classified with lime-soil mixtures and soils, and interpreted the mixing characteristics of Sammul based on types of tomb barrier. The tomb barrier which is directly effect to control the inner environment was made with high content of lime. But the finishing or bottom layer were made with low content of lime. Overall the LSMB with integrated wall has higher content of lime and physical property than the LSMB with layered wall. The soil which was compounded as a Sammul and collected near the Gungri Site had similar with mineralogical and geochemical characteristics. Therefore, it is presumed that the fine sand and yellow ocher that made as a Sammul, were used with soil that was distributed around the site. Meanwhile, large scale limestone quarry is distributed near the site. Especially, Gungri Site has a possibility of material supply through water transport, due to the sea route from Asan bay is connected near the site. Thus, there is the possibility of transportation of lime materials from nearby quarry.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.34 no.3
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• pp.268-278
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• 2001

To investigate sedimentary facies and environmental changes of the Nakdong River Estuary and its adjacent coastal area, the grain size analysis and measurement of organic matter, calcium carbonate, clay mineral and metallic elements were carried out for forty surface sediment samples. Based on regional distribution pattern and characteristics of the surface sediments, sedimentary facies in the study area can be divided into sand facies (TYPE I), mud facies (TYPE II) and sand-mud mixed facies (TYPE III). TYPE III is the transition of TYPE I and TYPE II in every aspects of sediment characteristics. It suggests that TYPE III may have been formed by the mixture of two different source of sediment : one derived from Nakdong River and the other resuspended fine-grained sediments from the Jinhae Bay by winnowing action during floods or storms. Among many aspects of environmental change after the construction of the Nakdong Barrage, the most significant is the increase of sand content off the sand barrier region. It could be explained by several reasons including decreased input of fine-grained sediment from river, increased hydrodynamic energy level off the sand barrier region and artificial effects such as dredging and dumping.

• Korean Journal of Agricultural Science
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• v.10 no.1
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• pp.110-117
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• 1983

This study was conducted to investigate the influence of load increment ratio on the secondary consolidation for the marine clay at Asan bay by the hyperbola method. The results were summarized as follow: 1. Calculated secondary consolidation by the hyperbola method was slightly less than the value of Casagrande's log t method, but the difference was very little, and the secondary consolidation could be easily calculated by the hyperbola method even if load increment ratio was small. 2. The secondary consolidation ratio was increased with the decrement of load increment ratio, and the creep phenomenon of the settlement curve occurred under the condition of small load increment ratio seemed to be caused by the secondary consolidation. 3. The secondary consolidation ratio occurred during the primary consolidation was irregular in the overconsolidated range, but it was increased with the decrement of load increment ratio in the normally consolidated range. 4. The coefficient of secondary consolidation was increased with the increment of the consolidation load, made a point of the inflection near preconsolidation. And the coefficient of secondary consolidation was decreased from consolidation load $2kg/cm^2$, showed independent of load increment ratio. 5. The coefficient of secondary consolidation was showed in proportion to compression index.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.5
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• pp.721-729
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• 2013

To improve the quality and functionality of the low salt squid Jeot-gal, extracts from three types of medicinal and edible plants (bay leaf, green tea, pine needle) were added. The quality characteristics, bioactivities, and shelf-lives of these preparations were determined at three different fermentation temperatures. The pH decreased more rapidly at higher temperatures, while the amount of volatile basic nitrogen (VBN), total viable cells, and amino nitrogen ($NH_2$-N) increased. The shelf-lives of Jeot-gal with natural plant extracts at $10^{\circ}C$ were 34~35 days, similar to the control. The major free and compositional amino acids of Jeot-gal were glutamic acid, proline, and alanine, while the major nucleotides (and related compounds) were hypoxanthine and inosine. In bioactivity assays, samples supplemented with plant extracts showed higher bioactivities than the control. The DPPH radical scavenging activity of ethanol extracts from Jeot-gal were stronger than the water extracts; in contrast, the water extracts were stronger for hydrogen peroxide scavenging activity. However, superoxide dismutase (SOD)-like activity and ${\beta}$-glucuronidase inhibitory activity were moderately low at 20 mg/mL. Based on sensory evaluation results, the quality of low salt squid Jeot-gal with natural plant extracts is similar to the control. Therefore, low salt squid Jeot-gal with natural plant extracts can be commercialized as a functional fermented food.

• Journal of the Korean Society for Marine Environment & Energy
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• v.11 no.3
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• pp.164-174
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• 2008

In this study we try to identify the three-dimensional mixing characteristics of Seomjin River discharges in Seomjin River Estuary and Gwangyang Bay using a seasonal field observation (CTD) during spring tide and a three-dimensional numerical model with EFDC (Environmental Fluid Dynamics Code). The tidal elevation conditions of the four main tidal harmonic constituents on the open boundary and river discharges and thermal effluents at the specific boundary are considered. The calculated harmonic constants of tide and tidal current agreed well with those of observations at two stations for tide and two stations for tidal current. The model successfully reproduced well known the estuarine circulation in Seomjin River Estuary where tide and river discharges are dominant forcings. In the winter mean discharges case, tidal currents move Seomjin River discharges in Seomjin River mouth and in the summer mean discharges case, river flows move Seomjin River discharges near ae Seomjin River Estuary. A three-dimensional mixing characteristics of Seomjin River Estuary show well a three-dimensional estuarine circulation and thermal effluents effect to the seasonal variation of river discharges.

• Journal of Navigation and Port Research
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• v.29 no.5 s.101
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• pp.389-394
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• 2005

The additional moment occurs because the superstructures of VLFS are influenced by wave loads instead of earthquake loads. In order to reduce the additional moment, this study used the semi-rigid connections which lie between fully rigid and pinned. If the semi-rigid connections are used for superstructures of VLFS, the moment of beams can be reduced and more economical construction will be possible. This study aims to show the effect of wave loads on structure and the efficiency of the semi-rigid connections due to wave loads by analyzing the time history responses. The dynamic behaviors of the rigid frame are compared with those of the semi-rigid frame considering of static loads, wave loads and combination loads for a four-bay, three-story frames. The semi-rigid connection type is a steel tubular column with square external-diaphragm connections and the time history analysis is used for the dynamic responses. The additional moment responses due to wave loads increase $33\%$ in the rigid frame, $26\%$ in the semi-rigid frame with the spring model.

• Economic and Environmental Geology
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• v.42 no.1
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• pp.55-72
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• 2009

The timing of hydrocarbon generation and expulsion from source rocks can be evaluated by reconstructing the geohistory of the basin using petroleum system modeling. The Tyee basin is generally considered having a high hydrocarbon generation potential For the southern part of the basin, the basin evolution from a structural and stratigraphic points of view, the thermal history, and the burial history were reconstructed and simulated using numerical tools of basin modeling. An evaluation of organic geochemistry for the potential source rocks and the possible petroleum systems were analysed to improve the understanding of the hydrocarbon charge of the basin. Organic geochemical data indicate that the undifferentiated Umpqua Group, mudstones of the Klamath Mountains, and coals and carbonaceous mudstones in the Remote Member and the Coquille River Member are the most potential gas-prone source rocks in the basin. The relatively high maturity of the southern Tyee basin is related to deep burial resulting from loading by the Coos bay strata. And the heating by intrusion from the western Cascade arc also affects to the high maturity of the basin. The maturation of source rocks, the hydrocarbon generation and expulsion were evaluated by means of basin modeling. The modeling results reveal that the hydrocarbon was generated in all potential source rocks and an expulsion only occurred from the Remote Member.