• Journal of Korean Society of Coastal and Ocean Engineers
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• v.17 no.4
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• pp.259-268
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• 2005

There has been a growing interest in the elimination of anoxic layer in the Youngsan River Estuarybecause the anoxic water mass caused mainly by the inflow of fresh water from the sea wall might cause the mass reduction of benthos during summer. An ocean outfall system to discharge treated wastewater into sea water may be used as one of the effective and economical ways to eliminate the anoxic layer. The suitable ocean outfall design is generally proposed for the prediction of the buoyant jet behavior in the near field. The parameters including CTD and current data are taken into account f3r more reliable buoyant jet behavior calculation. One of the numerical models, CORMIX 1, approved by EPA is used herein for the prediction of the trajectorial variation of the cross-sectional salinity and DO concentration distribution on the calculated buoyant jet boundary according to the tidal periods. On the basis of the results, it is suggested that the single port outfall is a useful system to eliminate the anoxic layer. Proper strategies are also proposed for achieving desirable ambient conditions.

• Korean Journal of Plant Resources
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• v.19 no.1
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• pp.97-104
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• 2006

This study was conducted to investigate effect of temperature and NaCl on the seed germination and water absorption of Thuja orientalis. Seeds were treated with 0, 500, 1,000, 2,000 and 4,000ppm of NaCl and placed in different chambers at 15, 20, 25 and $30^{\circ}C$, respectively. And seed properties and relative water absorptions were analyzed. Germination decreased with the increase of both temperature and NaCl concentration, and especially the difference was obvious at $30^{\circ}C$. Dormancy and mortality increased with the increase of temperature in non-NaCl treatment. Two-way analysis of variance showed significant effects of temperature, NaCl concentration and interaction between temperature and NaCl concentration (p<0.001). Mean germination time increased with the increase of NaCl concentration at 15, 20 and $25^{\circ}C$ but decreased at $30^{\circ}C$ because the seeds were mortal by NaCl high concentration, Germination speed and germination performance index decreased with the increase of NaCl concentration. Those represented decreasing tendency with NaCl concentration but high positive correlation with germination. Relative water absorption decreased with the increase of NaCl concentration and represented high values at $15^{\circ}C$, and showed high positive correlations with germination, germination speed and germination performance index. It was reported that the high temperature and salinity were inhibitive factors of seed germination of Thuja orientalis.

• Ocean and Polar Research
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• v.40 no.2
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• pp.69-75
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• 2018

We investigated the effects of environmental variations on the growth and survival rate of Stichopus japonicus to determine the optimum environmental conditions for its growth. Literature studies and a 12 month-long diver survey were carried out to understand the habitat, ecology and size of the surveyed area. Based on the collected data, we suggested optimum habitat conditions for releasing S. japonicus. Experiments on releasing S. japonicus were conducted in the breakwater of the Hwagye fishing cooperative in Hwagey-ri, Namhae-un, Gyeongsangnam-do, Korea. To implement the experiments, we divided the surveyed area into 4 sub-areas with different characteristics: (1) sand and silt zone; (2) artificial sea cucumber bank zone; (3) artificial rock bank zone; and (4) marine algae zone. The experiment lasted for 12 months. We released 32,000 sea cucumbers over $120m^2$ of each of the sand and silt zone, artificial rock bank zone and marine algae zone and released 6,000 sea cucumbers over $120m^2$ of the artificial sea cucumber bank zone. The average density of the released sea cucumbers from day 30 to day 360 after the releasing was conducted was the highest in the artificial sea cucumber bank zone ($23.7animal/m^2$), which was followed by artificial rock bank zone ($2.0animal/m^2$), marine algae zone ($1.9animal/m^2$) and sand and silt zone ($0.8animal/m^2$). The analysis on growth showed that the initial average weight of 2.3 g increased on day 360 after the releasing to 12.5 g in the artificial sea cucumber rank zone, 20.2 g in the sand and silt zone, 23.3 g in the artificial rock bank zone and 22.9 g in the marine algae zone. Results from the experiment along with the literature analysis suggest the following optimum habitat conditions: $10-15^{\circ}C$ water temperature; 28-34 psu salinity; 5-10 m water depth; 0.2-0.5 m/s velocity; rock, stone and muddy sand as substrate; and less than 20% mud in the substrate.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.8
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• pp.1184-1188
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• 2011

This study analyzed changes in the texture and salt content of Chinese cabbage after salting using different methods to determine the effects of low salt brining. To verify the possibility of brining under low salt concentration, Chinese cabbage was salted with 1%, 2%, 6%, and 10% salt solutions by pressing, pressure reduction, or steaming. After salting, the firmness (g, determined using the puncture test) of the Chinese cabbage changed according to the brining methods used, however, an increasing trend in rigidity was observed as the salinity increased. Because the power applied during pressing or pressure reduction treatments is higher, the firmness of and penetration time on the surface of the brined Chinese cabbages after these treatments increased more in the 6% salt solution cabbage. Additionally, the Chinese cabbages treated with steam showed significantly higher firmness and penetration time than those treated by pressing and pressure reduction. As a result of pressing the 6% salt concentrated cabbage with 1.35 $kg{\cdot}f/cm^2$, a pressure reduction from 250 mmHg, and steaming at 100$^{\circ}C$ for 1 min, the cabbage had roughly 2% of the salt concentration, ultimately. These physical treatments of pressing, pressure reduction, and steaming could be used as new methods for preparing salted Chinese cabbage with low salt concentrations for general use.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.26 no.8
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• pp.597-601
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• 2013

The accelerated thermal aging of a CSPE were carried out for 0, 80.82, 161.63 days at $100^{\circ}C$, which are equal to 0, 40 and 80 years of aging at $50^{\circ}C$, respectively. The volume electrical resistivities of the seawater and freshwater flooding were measured through 3-terminal circuit diagram. The volume electrical resistivities of the 0y, 40y and 80y were $2.454{\times}10^{13}{\sim}1.377{\times}10^{14}{\Omega}{\cdot}cm$, $1.121{\times}10^{13}{\sim}7.529{\times}10^{13}{\Omega}{\cdot}cm$ and $1.284{\times}10^{13}{\sim}8.974{\times}10^{13}{\Omega}{\cdot}cm$ at room temperature, respectively. The dielectric constant of the 0y, 40y and 80y were 2.922~3.431, 2.613~3.285 and 2.921~3.332 at room temperature, respectively. It is certain that the ionic ($Na^+$, $Cl^-$, $Mg^{2+}$, ${SO_4}^{2-}$, $Ca^{2+}$, $K^+$) conduction current was formed by the salinity of the seawater. The volume electrical resistivity of the cleaned CSPE via freshwater trends slightly upward with the number of dried days at room temperature. As a result, the $CH_2$ component of thermally accelerated aged CSPE decreased after seawater and freshwater flooding for 5 days respectively, whereas the atoms such as Cl, O, Pb, Al, Si, Sb, S related with the conducting ion ($Na^+$, $Cl^-$, $Mg^{2+}$, ${SO_4}^{2-}$, $Ca^{2+}$, $K^+$) component increased relatively.

• Culinary science and hospitality research
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• v.16 no.4
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• pp.247-259
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• 2010

In order to apply oriental medicine materials, which are applicable to the LOHAS concept demanded recently in society, to sauces, this study added different amounts of Omija, which has been proved to have various efficacies, effects and functions, to Bulgogi sauce with soy sauce as its main ingredient and analyzed the functionality of the prepared sauce through physical and sensory tests. General component analysis showed that, with increase in the Omija content, water content, crude ash and crude protein decreased, and crude fat was not detected As to color, L-value gradually increased with Omija content increased, and a-value indicating redness also increased as Omija extract added increased The higher the Omija content was, the lower pH and salinity were and the higher viscosity was. In the quantitative descriptive analysis of Omija Bulgogi sauce, with increase in the Omija content, color, flavor, taste and aftertaste grew stronger, and in the results of palatability test, the sauce containing Omija 5% was preferred most in all the evaluated items. In the quantitative descriptive analysis of Omija Bulgogi, with increase in the amount of Onija extract added, the strength of color, the flavor of sauce, and the taste of Omija grew stronger and the unpleasant smell, saltiness, sweetness and unpleasant taste grew weaker. Summing up the result of this study, when we tested five specimens of different Omija contents including a control, the specimen of 5% content was preferred most This result suggests that other kinds of fruit juice may be usable in soy sauce Bulgogi sauce and continuous efforts should be made to develop new types of Bulgogi sauce.

• The Korean Journal of Ecology
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• v.26 no.3
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• pp.135-142
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• 2003

Four legume plants showed better growth by the external nitrogen supply rather than the symbiotic nitrogen fixation only under salt additions. In case of Glycine max and Phaseolus angularis, total nitrogen contents decreased by high salinity level but their amino acid levels significantly increased with the increase of salt treatments and indicated high soluble-/insoluble-N ratios. Cassia tora and Albizzia julibrissin contained less amino acids than G. max and P. angularis but total N (esp. insoluble N fraction) increased with higher salt levels. Asparagine occurred as a main amino acid especially in G. max and P. angularis and can be seen as potential N-storage form in these plants. It might be play an important role for the osmoregulation mechanism under the saline condition. Meanwhile, to investigate what kinds of nitrogen sources are effective for overcoming salt stress on soybean plants, various N forms and concentrations (NH₄NO₃-N, NO₃-N, NH₄NO₃-N; 2.5 and 5 mM) were additionally supplied to the salt gradient medium. Soybean plants treated with NH₄NO₃-N showed the best growth up to 40 mM NaCl and NO₃- fed plants indicated good growth even at 80 mM NaCl treatments. Contrary to NH₄NO₃- and NO₃- fed plants, NH₄/sup +/- fed plants showed remarkable growth reduction and died by 40 and 80 mM NaCl treatments after the first harvest (15th day). Consequently, these results suggest that salt excluding and resistant capacities of soybean plants under NaCl treatments are increased in order of NH₄ - N, control, NO₃- N and NH₄NO₃- N depending on N concentration except NH₄- N treatments.

• Journal of Biosystems Engineering
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• v.25 no.3
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• pp.213-220
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• 2000

Grafting of fruit-bearing vegetables has been widely used to increase the resistance to soil-borne diseases, to increase the tolerance to low temperature or to soil salinity, to increase the plant vigor, and to extend the duration of economic harvest time. After grafting, it is important to control the environment around grafted seedlings for the robust joining of a scion and rootstock. Usually the shading materials and plastic films are used to keep the high relative humidity and low light intensity in greenhouse or tunnel. It is quite difficult to optimally control the environment for healing and acclimation of grafted seedlings under natural light. So the farmers or growers rely on their experience for the production of grafted seedling with high quality. If artificial light is used as a lighting source for graft-taking of grafted seedlings, the light intensity and photoperiod can be easily controlled. The purpose of this study was to develop a prototype system for the graft-taking enhancement of grafted seedlings using artificial lighting and to investigate the effect of air current speed on the distribution of air temperature and relative humidity in a graft-taking enhancement system. A prototype graft-taking system was consisted by polyurethane panels, air-conditioning unit, system controller and lighting unit. Three band fluorescent lamps (FL20SEX-D/18, Kumho Electric, Inc.) were used as a lighting source. Anemometer (Climomaster 6521, KANOMAX), T-type thermocouples and humidity sensors (CHS-UPS, TDK) were used to measure the air current speed, air temperature and relative humidity in a graft-taking system. In this system, air flow acted as a driving force for the diffusion of heat and water vapor. Air current speed, air temperature and relative humidity controlled by a programmable logic controller (UP750, Yokogawa Electric Co) and an inverter (MOSCON-G3, SAMSUNG) had an even distribution. Distribution of air temperature and relative humidity in a graft-taking enhancement system was fairly affected by air current speed. Air current speed higher than 0.1m/s was required to obtain the even distribution of environmental factors in this system. At low air current speed of 0.1m/s, the evapotranspiration rate of grafted seedlings would be suppressed and thus graft-taking would be enhanced. This system could be used to investigate the effects of air temperature, relative humidity, air current speed and light intensity on the evaportranspiration rate of grafted seedlings.

• Applied Biological Chemistry
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• v.47 no.2
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• pp.208-215
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• 2004

As a part of a study on the effective use of cultured oyster, oyster powder-added soybean pastes were prepared and its characteristics were examined. As the concentration of oyster powder added to commercial soybean paste was increased, the moisture level decreased, the crude and amino nitrogen content increased with no change in the salinity and titratable acidities. Also, the color of the soybean paste changed to a darker color as the concentration of oyster powder added to commercial soybean paste increased. Judging from the results of the above experiment and sensory evaluation, the optimal additive concentration of oyster powder to commercial soybean paste was revealed as 9%. The total amino acid content of oyster powder-added soybean paste was 2% higher than that of commercial soybean paste. The ratio of calcium and phosphorus of oyster powder-added soybean paste was about 1:2-2:1, an improvement in calcium absorption as compared to commercial soybean paste. Functional fatty acids, such as 20:5n-3 and 22:6n-3, were not detected in commercial soybean paste but detected in oyster powder-added soybean paste. The major free amino acids in oyster powder-added soybean paste were glutamic acid and aspartic acids. According to the above results, the nutritional, functional and taste properties of commercial soybean paste were improved while reducing preparation time of the housewife.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.31 no.3
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• pp.256-263
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• 1995

This paper presents the evidence on the considerably strong stratification - destratification(SD) phenomena during spring - neap tidal cycle in summer of 1992 based on the observed temperature, salinity and density data. To find out the main factors causing SD in the bay, we computed the rate of potential energy balance of the surface heat flux, tidal and wind stirring proposed by Simpson and Hunter (1974) and Simpson and Bowders (1981) using observed data. It was found that the energy of the wind stirring was one - order smaller than those of the heat flux and the tidal stirring. It means that the variation of stratification phenomena in the bay mainly depend on tidal stirring and sea surface heating in summer if there was no exceptionally strong wind event like a typhoon. Finally, we tested the effects of typhoon on the mixing characteristics of the bay using the example of a empirical typhoon model. It was found that when wind speed is larger than 15m/sec in Deukryang Bay, the wind energy was always larger than the average heating energy based on empirical typhoon model test. Particularly, typhoon passed on the left side of the bay, strong wind energy happened, which is almost the same as tidal energy of spring tide.