• 한국연소학회:학술대회논문집
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• 2006.10a
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• pp.36-41
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• 2006

A simplified model of plastic layer and internal gas pressure In a coke oven is presented. We calculate internal gas pressure using presented model. And results are compared with calculated results using experimental data. Results show the difference of internal gas pressure by coal composition. The model is used to show that the permeability at the resolidification end of the plastic layer is a key determinant of the magnitude of the internal gas pressure.

• Korean Journal of Food Science and Technology
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• v.19 no.6
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• pp.463-470
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• 1987

In order to develop a rapid predicting method of the shelf-life of moisture sensitive foods and establish their proper packaging methods, the qualify changes and shelf-life of dired laver as a model food were studied by the computer simulation. A mathematical model of the relationship between the rate constants of chlorophyll a and water activity was established at $10^{\circ}C,\;25^{\circ}C$ and $40^{\circ}C$. Computer simulation to predict water activity and chlorophyll a was developed by considering the simultaneous influence of storage conditions such as water content of products, storage temperature and relative humidity, packaging materials. Simulated quality changes of dried laver was in good agreement with the experiment data. Chlorophyll a and sensory score decreased as the water activity increased. And correlation coefficient between the sensory scores and the contents of chlorophyll a was very high as 0.991. The critical water activity by sensory evaluation was around 0.55. The shelf-life of dried laver packaged with plastic films could be predicted from the above results in various storage conditions.

• Journal of the Korean Society of Marine Environment & Safety
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• v.28 no.6
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• pp.1078-1085
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• 2022

Fouling organisms attached to a ship not only greatly increase the resistance of the ship as they grow on the hull but also cause disturbances in local marine ecosystems as they move with the ship. Accordingly, the International Maritime Organization has started discussing the removal of biofouling and evaluation of cleaning performance to prevent the migration of hull-fouling species. In this study, specimens of FRP(Fiber Reinforced Plastic), HDPE(High Density Polyethylene), and CFRP(Carbon Fiber Reinforced Plastic) materials used for small ship construction were cured in Gyeokpo Port (Jeonlakbuk-do) for about 80 days. Then, attached organism removal experiments were performed using a water jet nozzle. The results show that seaweeds, such as laver, were removed when the distance between the nozzle and the specimen was 1.8 cm and the pressure was 100 bar. Furthermore, it was confirmed that the cleaning of barnacles was possible only when the pressure was 200 bar or more.