• 한국해양학회지
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• v.4 no.2
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• pp.49-67
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• 1969

A quantitative phytoplankton study in Korean waters was commenced in 1964 as a part of the primary production studies of Koreans seas, and it was continued with the cruises for Cooperative Studies of the Kuroshio(C.S.K) in 1965-1968. Phytoplankton samples were taken by dipping about 500ml of sea water from the surface, and then fixed by ading neutralized formlin. This report deals with the results obtained during 1965-1966. I examined a total of 298 samples of surface phytoplankton collected in the wate neighboring Korea in the above-mentioned period, and detected 147 species of diatoms and 22 species of dinoflagellates. Among them 123 species of diatoms and 18 species of dinoflagellates occured in the Japan Sea region, 133 species of diatoms and 11 species of dinoflagellates occured in the Korea Strait region, and 49 species of diatom and 8 species of dinoflagellates occured in the Yellow Sea region. And thd phytoplankton standing crops are dept in a fair abundance in the Japan Sea area all the year round, and are poor in the Yellow Sea area. The seas surrounding Korea are divided into seven regions by the planktological characteristics; northern and southern parts of the Japan Sea, eastern, western and southern parts of the Korea Strait, southern and northern parts of the Yellow Sea. The representative of the phytoplankton community in each sea region is generalized as follows; northern part of the Japan Sea is dominant with Chaetoceros group, southern part of the Japan Sea is dominant with Chaetoceros group and Skeletonema costaum, eastern part of the Korea Strait is dominant with Chaetoceros group and Pleurosigma sp., southern part of the Korea Strait is dominant with Chaetoceros group and Rizosolenia group, western part of the Korea Strait is most poor in phytoplankton, southern part of the Yellow Sea is dominant with Pleurosigma sp. and Coscinodiscus group, and northern part of the Yellow Sea is dominant with Pleurosigma sp. and Eucampia zoodiacus. Chaetoceros curvisetus, Leptocylindrus danicus, Pleurosigma normanii, Thalassionema nitzschioides, Thalassiothrix flauenfeldii appeared all the year round in the neighboring sea of Korea. There were 24 species (18 species of diatoms and 6 species of dinoflagellates) of the pecuriar phytoplankton in the Japan Sea, 27 species (25 species of diatoms and 2 species of dinoflagellates) of that in the Korea, and 7 species (5 species of diatoms and 2 species of dinoflagellates) of that in the Yellow Sea, respectively.

• The Journal of Engineering Geology
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• v.19 no.3
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• pp.351-363
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• 2009

Two orthogonal joint sets develop well only in sandstone beds in the sandstone-mudstone sequences of Gumi and Dasa outcrops within Cretaceous Gyeongsang Basin. And various joint data are similar in the beds of the same thickness in both outcrops, meaning that the joint sets were homogeneously produced by extensional deformation in the same regional stress field. Most of joints in the sandstone beds are orthogonal to, and confined by bed boundaries, which are believed to be formed by hydrofracturing during consolidation after burial. Two orthogonal joint sets are considered to be almost coeval on the basis of mutual abutting relationship which makes up fracture grid-lock and a product of rapid switching of ${\sigma}_2$ and ${\sigma}_3$ axes with constant ${\sigma}_1$ direction oriented to vertical. The joint sets in the sandstone beds show planar surfaces, parallel orientations and regular spacing, with joint spacing linearly proportional to bed thickness. The spacing distributions of the joints seem to correspond to log-normal to almost normal distribution in most of the beds. But multilayer joints do not display regular spacing and dominant size. Either joint set in this study is characterized by a high level of joint density and a saturated spacing distribution as indicated by the mode/mean ratio values and the Cv(coefficient of variance) values. Joint aperture tends to increase with the vertical length of the joints controlled by bed thickness.

• Korean Journal of Food Science and Technology
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• v.32 no.4
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• pp.920-927
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• 2000

Angiotensin converting enzyme(ACE) inhibitory activity of Kimchi added with salted-fermented fish products(SFFP), such as salted-fermented anchovy(SFA), salted-fermented anchovy sauce(SFAS), low salt-fermented anchovy sauce(LSFAS), salted-fermented small shrimp(SFS), low salt-fermented sandlance sauce(LSFSS) and their alternatives, such as oyster hydrolysate(OH), Alaska pollack hydrolysate(APH) and sea-staghorn extract(SSE) were studied during fermentation at $20^{\circ}C,\;10^{\circ}C\;and\;4^{\circ}C$. ACE inhibitory activities of Kimchi samples added with SFFP were increased until some fermentation period and then kept similarly constant levels at every fermentation temperature. Similar tendencies were occurred in amino nitrogen (AN) content. ACE inhibitory activities of Kimchi samples added with SFFP alternatives rapidly increased in 1st or 2nd day fermentation and then very slowly increased but AN contents showed roughly constant levels $(400{\sim}600\;mg/100\;g)$ in every fermentation temperature. Kimchi added with LSFAS had higher ACE inhibitory activity (>80%) with elevated level of AN (>600 mg/100 g) among the tested Kimchi samples. Kimchi samples added with SFFP alternatives also showed comparable activity to Kimchi added with SFFP This study shows that Kimchi added with SFFP and their alternatives is a good source as a functional food.

• Korean Journal of Food Science and Technology
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• v.32 no.4
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• pp.942-948
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• 2000

Nitrite scavenging activity of Kimchi added with salted-fermented fish products(SFFP), such as low salt-fermented anchovy sauce(LSFAS), salted-fermented anchovy sauce(SFAS), salted-fermented anchovy(SFA), salted-fermented small shrimp(SFS), low salt-fermented sandlance sauce(LSFSS) and their alternatives, such as oyster hydrolysate(OH), Alaska pollack hydrolysate(APH) and Sea-staghorn extract(SSE) were studied during fermentation at $20^{\circ}C,\;10^{\circ}C\;and\;4^{\circ}C$. Nitrite contents of Kimchi samples added with SFFP were roughly decreased except Kimchi added with SFS and SFAS, which increased at the 2nd day of fermentation. Fermentation of Kimchi at $4^{\circ}C\;and\;10^{\circ}C$ resulted a decrease in nitrite(<5 ppm). Nitrite contents of Kimchi samples added with SFFP alternatives rapidly decreased in the initial fermentation and then kept a low level (<2 ppm). Nitrite scavenging effects of Kimchi samples added with SFFP and their alternatives were steady during fermentation, showing a little variation in samples added with SFFP. Samples added with LSFAS and OH showed higher nitrite scavenging effects(90%) than others$(70{\sim}80%)$.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.35 no.3
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• pp.297-301
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• 2002

To investigate changes of components in salt-fermented blenny, Enedrias nebulosus sauce during fermentation, various chemical properties were examined at 2$\~$3 months intervals during 18 months of fermentation. The degree of hydrolysis increased sharply until 6 months of fermentation and showed the gentle increasement after that. On the other hand, the contents of total and amino nitrogen, total ATP related compounds increased gradually during 18 months of fermentation, The hypoxanthine and uric acid were the most abundant in ATP related compounds, ranging from $80.1\% to $90.5\%. After 18 months of fermentation, sauce was rich in free amino acids such as glutamic acid, alanine, lysine, valine, leucine in that order.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.17 no.3
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• pp.159-164
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• 1984

The present studies were conducted to evaluate the sterilizing efficiency of the thermal processes for the canned sea-mussel products, such as canned boiled sea-mussel in brine (packed into No. 1 flat can) and canned smoked sea-mussel in oil (packed into No. 3B square can), with the purpose of deciding the adequacy of the processes. Heat penetration was tested three times with three cans at a time for each canned product. The tip of the applicator was fixed on the position a little below the geometrical center of the can. The test cans were placed in the middle layer of the basket in which the same canned products were loaded with, and the test cans were arranged to the front, the middle and the rear in the retort. The heat penetration curve of the canned boiled sea-mussel in brine showed a broken logarithmic heating curve while that of the canned smoked sea-mussel in oil showed a simple logarithmic heating curve. The calculated $F_0$ value for the canned boiled sea-mussel in brine was 25.33 and the canned smoked sea-mussel in oil was 13.84. Additionally, the nomographs represents the relationship between $F_0$ values and B values(process time including $42\%$ of come-up time) for the canned sea-mussel products were constructed.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.11
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• pp.483-490
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• 2016

Automobile door latch is a fine design and assembly techniques are required in order to produce them in a small component assembly shape such as a spring, injection products, a small-sized motor. The door latch is fixed to not open the door of the car plays an important role it has a direct impact on the driver's safety. In this study, during trimming of the terminals of the connector main components of the car door latch, reduce rollover and conducted a research to find a suitable effective shear surface. Using the Taguchi method with orthogonal array of Finite Element Analysis and optimal Design of Experiments were set up parameters for the shear surface quality of the car door latch connector terminals. The design parameters used in the analysis is the clearance, the radius, and the blank holding force, the material of the connector terminal is a C2600. Trimming process optimum conditions suggested by the analysis has been verified by experiments, the shear surface shape and dimensions of a final product in good agreement with forming analysis results.Taguchi method from the above results in the optimization for the final rollover and effective shear surface improved for a vehicle door latch to the connector terminal can be seen that the applicable and useful for a variety of metal forming processes other than the trimming process is determined to be applicable.

• BMB Reports
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• v.51 no.10
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• pp.532-537
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• 2018

Prostaglandin $E_2$ ($PGE_2$), a major product of cyclooxygenase-2 (COX-2), plays an important role in the carcinogenesis of many solid tumors, including colorectal cancer. Because $PGE_2$ functions by signaling through $PGE_2$ receptors (EPs), which regulate tumor cell growth, invasion, and migration, there has been a growing amount of interest in the therapeutic potential of targeting EPs. In the present study, we investigated the role of EP4 on the effectiveness of cordycepin in inhibiting the migration and invasion of HCT116 human colorectal carcinoma cells. Our data indicate that cordycepin suppressed lipopolysaccharide (LPS)-enhanced cell migration and invasion through the inactivation of matrix metalloproteinase (MMP)-9 as well as the down-regulation of COX-2 expression and $PGE_2$ production. These events were shown to be associated with the inactivation of EP4 and activation of AMP-activated protein kinase (AMPK). Moreover, the EP4 antagonist AH23848 prevented LPS-induced MMP-9 expression and cell invasion in HCT116 cells. However, the AMPK inhibitor, compound C, as well as AMPK knockdown via siRNA, attenuated the cordycepin-induced inhibition of EP4 expression. Cordycepin treatment also reduced the activation of CREB. These findings indicate that cordycepin suppresses the migration and invasion of HCT116 cells through modulating EP4 expression and the AMPK-CREB signaling pathway. Therefore, cordycepin has the potential to serve as a potent anti-cancer agent in therapeutic strategies against colorectal cancer metastasis.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.22 no.4
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• pp.272-278
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• 2010

Some recent researches reported that high temperature rising decreases the carbonation depth of concrete, which is contrary to the previous research results. Carbonation has been known as a reaction between calcium hydroxide and carbon dioxide. But a few researches showed that the other cement hydrates as well as calcium hydroxide react with carbon dioxide. This paper investigates the influence of temperature on carbonation and the variation of $Ca(OH)_2$ and $CaCO_3$ by carbonation. In order to estimate the carbonation depth and the quantities of reactant and product of carbonation reaction, phenolphthalein testing and thermagravimetric analyzer test were conducted. The measurement of carbonation depth with temperature showed that the temperature increase from $20^{\circ}C$ to $30^{\circ}C$C in carbonation environment makes the carbonation depth larger, but the increase from $30^{\circ}C$ to $40^{\circ}C$ has a small influence on the carbonation depth. Comparing calcium hydroxide and calcium carbonate with temperature, the quantity of $CaCO_3$ of specimen carbonated at $30^{\circ}C$ is greater than that of specimen carbonated at $40^{\circ}C$ and the quantity of $Ca(OH)_2$ of specimen carbonated at $30^{\circ}C$ is similar to that of specimen carbonated at $40^{\circ}C$. This observation shows that there is the optimum temperature increasing carbonation depth and the optimum temperature is close to $30^{\circ}C$.

• Applied Chemistry for Engineering
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• v.29 no.4
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• pp.419-424
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• 2018

In this work, effect of the culture medium composition on the fermentation process of Clostridium ljungdahlii, which is acetogenic bacteria to product ethanol from synthesis gas, was examined to improve the microbial growth and ethanol production. Components of the culture medium such as yeast extract, fructose, $NH_4Cl$, and $K_2HPO_4$ were selected as influence factors for the cell growth and ethanol production. As the concentration of yeast extract increased, both of the cell growth and ethanol production increased. And the ethanol productivity was the highest at an yeast extract of 0.05 g/L, which is lower than that of base medium. As the concentration of fructose increased, the cell growth increased, but the ethanol production decreased when the concentration of fructose was higher than that of base medium (5 g/L). In an experiment with the yeast extract of 5 g/L, produced ethanol concentration was the highest (0.297 g/L) when fructose concentration was 5 g/L, however, the specific ethanol productivity was higher (0.281 g/g DCW) when the fructose was not added due to very low cell mass. The cell growth and ethanol production were not significantly influenced by $NH_4Cl$ concentration, however the growth inhibition was observed at a 30 g/L of $NH_4Cl$. When the concentration of $K_2HPO_4$ increased, both of the cell growth and ethanol production increased. In experiments with $NH_4Cl$ and $K_2HPO_4$, specific ethanol productivities were higher when the low concentration of yeast extract was used.