• Korean Journal of Fisheries and Aquatic Sciences
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• v.4 no.1
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• pp.22-30
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• 1971

Sea mussel Mytilus edulis, world-widely distributed, is a sort of popular food in Korea. The demands of high quality and mass production are not being satisfied since it is usually sun dried. A rapid dehydration and the treatment of food additives to improve the quality of the product seems to be required. In this paper, the effect of antioxidants and EDTA treatment was studied when sea mussel was pressed and hot-air dehydrated for 10 hours at 45 to $52^{\circ}C$ under the air flow rate of 3 meter per second. The results are as follows: 1) Cooked and pressed sea mussel was dehydrated mere rapidly than cooked without pressing. 2) The rehydration rate of pressed and dehydrated sea mussel was higher than that of the unpressed. 3) Among six samples, BHA treated material showed the best color preservation during dehydration and storage. The treatment of Teonox-II was also effective following BHA. 4) The effects of antioxidants used during dehydration and storage were in order of BHA, Tenox-II and NDGA treatment, while EDTA was ineffective. 5) No significant difference in rehydration rate was found between those treated with antioxidants or EDTA and the untreated. 6) The amount of soluble protein was higher in the samples treated with antioxidants than in EDTA treated or untreated samples. 7) The results suggest that the treatment of BHA and pressing process produce improved product in quality which gives higher amount of soluble protein and better rehydration, color preservation and preventive effect of rancidity.

• Transactions of the Korean hydrogen and new energy society
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• v.26 no.3
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• pp.234-240
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• 2015

In the face of the world's growing energy storage needs, liquid hydrogen offers a high energy density solution for the storage and transport of energy throughout society. A 5 L liquid hydrogen storage tank has been designed, fabricated and tested to investigate boil-off rate of liquid hydrogen. As the insulation plays a key role on the cryogenic vessels, various insulation methods have been employed. To reduce heat conduction loss, the epoxy resin-based insulation supports G-10 were used. To minimize radiation heat loss, vapor cooled radiation shield, multi-layer insulation, and high vacuum were adopted. Mass flow meter was used to measure boil-off rate of the 5 L cryogenic vessel. A series of performance tests were done for liquid nitrogen and liquid hydrogen to compare with design parameters, resulting in the boil-off rate of 1.7%/day for liquid nitrogen and 16.8%/day for liquid hydrogen at maximum.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.52 no.4
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• pp.299-307
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• 2016

This study aims to investigate effects of the length of the buoy and sand bag line on the loss of webfoot octopus pot. A numerical modeling and simulation was carried out to analyze the process that the pot gear affected by wave using the mass spring model. Through the simulation, tensions of sand bag line under various condition were investigated by length of buoy and sand bag line. The drag force and coefficient k of an artificial shell used in the webfoot octopus pot was obtained from an experiment in a circular water channel, and the coefficient k was applied to the simulation. To verify the accuracy of the simulation model, a simple test was conducted into measuring a rope tension of a hanging shell under flow. Then, the test result was compared with the simulation. The lengths of the buoy line in the simulation were 1.12, 1.41, 1.80, 2.23, 2.69, and 3.17 times of water depth. The lengths of sand bag line were 10, 20, 30, and 40 meters, and conditions of water depth were 8, 15, 22 meters. 4 meter height and 8 second period of wave were applied to all simulations. As a results, the tension of the sand bag line was decreased as the buoy and sand bag line were increased. The minimum tension of the sand bag line was appeared in conditions that the length of the buoy line is twice of water depth and the sand bag line length is over 40 meters (except in case of depth 8 meters.).

• Journal of Korean Society on Water Environment
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• v.22 no.1
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• pp.128-133
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• 2006

The paved areas in nonpoint source are highly polluted landuses because of high imperviousness and high pollutant mass emissions from vehicle activities. Particularly, the metal pollutants are a big issue in the paved area. It is usually washed-off during storms by adsorbing on sediments or soluble status. Therefore, this research was achieved for understanding the characteristics of metal pollutants in stormwater runoff in highways. Five monitoring sites were equipped with an automatic rainfall gage and an automatic flow meter. This manuscripts will summarize the washoff characteristics of metal pollutants and its concentration changes during storms. Usually first flush phenomenon was observed for all of the storm events and visibly confirmed with hydro- and polluto-graphs. Also it was coincided with the tendency of particulates and organic matters. The decrease rate per total reduced amount for metals during initial 30-min storm duration was obtained on 80%. The result may be able to use for determining the economical treatment criteria for stormwater runoff in highways.