• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2003.10a
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• pp.24-29
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• 2003

Deep sea water has cold temperature, abundant nutrients and minerals, and good water quality that is pathogen-free and stable. Compared with surface water, deep sea water contains more nutrition salt, such as nitrogen and phosphor. Moreover, if has the good balance of minerals. Because of the ability of the spray drying process to produce a free-flowing power considering of spherical particles with a well-defined size distribution and the rapid drying times for heat-sensitive material, spray drying is attractive for a wide range of applications spray drying is a unique unit operation in which powders are produced from a liquid feed in a single processing step. Key component of the process are atomizer, spray chamber. Design of spray chamber should be based on the atomizer type, the production rate, and the particle size required. Because of the complex processes taking place during spray drying, traditional design method are based on pilot-plant tests and empirical scale-up rules. Modern technique such as CFD have a role to play in design and troubleshooting.

• Korean Journal of Food Science and Technology
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• v.44 no.6
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• pp.716-721
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• 2012

This study was designed to compare the quality characteristics of spray-dried (SD) and freeze-dried (FD) powders prepared with hot water extracts of sea mustard (Undraia pinnatifada) and sea tangle (Laminaria longissima). The moisture content of FD seawed was lower than that of SD, and sea mustard had a higher overall moisture content than sea tangle. The alginic acid content of SD seaweed was significantly higher than that of FD seaweed for both species. There were relatively higher contents of phenolic compounds in SD powders than in FD powders. DPPH radical scavenging ability was significantly greater in SD seaweed, and also, SOD-like activity in SD powders was higher than those of FD powders. However, the nitrite scavenging activity of FD powders of sea mustard (10 mg/mL) was higher than that of SD. In conclusion, spray-dried sea mustard and sea tangle extracts exhibited higher physiological functionalities than their freeze-dried counterparts.

• 한국전산유체공학회:학술대회논문집
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• 2008.03b
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• pp.691-694
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• 2008

Spray characteristics of the APU simplex fuel nozzle are investigated. Four flight conditions such as sea level idle, sea level max power, 20,000 feet idle, 20,000 feet max power are used as spray experimental conditions. Spray visualization was performed by using ND-YAG laser. Droplet size and velocity were measured by using PDPA(Phase Doppler Particle Analyzer) system. From the test result, SMD is 100 ${\mu}$m�� and velocity is 10 m/s at 20,000 ft idle condition. In this condition, flame unstability could be occurred due to the higher drop diameter. Therefore it is necessary to decrease the droplet diameter in the high altitude condition.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2007.11a
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• pp.359-364
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• 2007

Spray characteristics of the APU gas turbine engine were investigated. In order to understand blow out phenomena of the APU engine, we performed fuel spray test. In the test, four operating conditions such as sea level idle, sea level max power, 20,000 feet idle, 20,000 feet max power were used as spray experimental conditions. PDPA(phase Doppler Particle Analyzer) was used for measuring the particle diameter and velocity. Also spray visualization was performed by using ND-YAG sheet laser beam. From the test result, in the case of 20,000 feet idle condition, SMD is about 100 ${\mu}m$ and maximum particle velocity is about 10 m/s. For the flame stability, spray quality should be improved at 20,000 feet idle condition.

• Corrosion Science and Technology
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• v.9 no.6
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• pp.317-324
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• 2010

Marine transportation by ships is characterized by remote, large-volume and lower rates than the others carry system. Ships account for over 80% of all international trading, and marine transportation is an internationally competitive, strategic, and great national important industry. The construction of larger and faster ships has brought about many problems such as cavitations and erosion corrosion. Cavitations and erosion corrosion make damages on materials and leads to break down members due to continuous physical contacts with shock waves and fluids from the generation and extinction of air bubbles in sea water vortex. The steel used for ship constructions was spray-coated with Al wire, and additionally sealed with fluorine silicone sealing material. Results of experiment, corrosion resistance of sealed thermal spray coating was improved, however in cavitation resistance, the large effect was not appeared. Accordingly, this study applied for thermal spray coating to provide better electrochemical characteristics and corrosion resistance in marine environment.

• Journal of the Korean Society of Propulsion Engineers
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• v.12 no.1
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• pp.29-36
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• 2008

Spray characteristics for APU gas turbine engine are investigated. In the test, four flight conditions such as sea level idle, sea level max power, 20,000 feet idle, 20,000 feet max power are used as spray experimental conditions. Spray visualization was performed by using ND-YAG laser bean PDPA(Phase Doppler Particle Analyzer) was used for measuring the particle diameter and velocity from 20 mm to 100 mm from discharge orifice. From the test result, SMD is $90{\sim}95\;{\mu}m$ 맛 20,000 ft idle condition and SMD is $60{\sim}75\;{\mu}m$ at sea level idle condition. Also SMD is $55{\sim}65\;{\mu}m$ at 20,000 ft max power condition and SMD is $30{\sim}70\;{\mu}m$ at sea level max power condition. In the case of 20,000 ft idle condition, combustion instability could be occurred due to the higher drop diameter. Therefore it is necessary to decrease the droplet diameter in the high altitude condition.

• Korean journal of applied entomology
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• v.19 no.4 s.45
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• pp.212-220
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• 1980

The purpose of this study is to establish a standard amount of pesticide per unit area of the lumber over the sea level. This establishment is required in applying the sea water dipping disinfection method to the imported soft woods to control the pests living on the surface of the lumber. The major findings of this study are as follows; 1. The average length and diameter of the imported soft wood was respectively 11.12m and 76.46Cm. 2. The average cubic content of the lumber over the sea level to the whole cubic content was 20.82 percent. 3. The ratio of the lumber over the sea level to the whole cubic content was 2.3356 at the $95\%$ significance level. 4. The sampling error of the ratio of the area of the lumber over the sea level to the cubic content was lower in the case of the pieces of lumber in a vessel than the average between ten tressels. 5. The optimum amount of pesticide spray per $1\;M^2$ of the soft wood was 0.298 cc in the case of using the hand spray, but 0.245 cc the motor spray. 6. For example, in the case of applying the sea water dipping disinfection method to the 5,000 $M^3$ of the imported soft wood, the required amount of pesticide with a motor spray can be estimated as follow. $$5,000\;M^3\times2.333=11,678\;M^2$$ $$11,678M^2\times0.295=3,445cc$$.

• Journal of Surface Science and Engineering
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• v.48 no.6
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• pp.349-353
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• 2015

In this paper, arc thermal spray coating was conducted onto the SS400 steel using Inconel 625 wires in order to improve the durability of marine steel structures, and then investigated cavitation damage behavior of Inconel 625 coating layer in sea water. For the Inconel 625 coating layer, surface hardness appeared similar to that of existing high velocity oxy-fuel coating technology with 380~480 HV, but the porosity of about 6 % was larger relatively. During the cavitation experiment, pit damages were originated and grown at the rough surface and pore defect area of Inconel 625 coating layer. And, after the 72 hours of experimental time, weight loss of Inconel 625 coating layer exhibited gradually increasing tendency due to surface damage effect of the undercut.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2013.11a
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• pp.104-105
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• 2013

The buildings constructed with steel structure is coated with certified fire resistive material to resist from fire. Coating materials lose their initial performances as time passes, so they need some maintenance. Fireproof spray-application also loses its performance and this performance loss of thr fireproof spray-application is very important because fire resistance of buildings depends on fireproof spray-application. So this study is to develop Acceleration durability test method of Fireproof spray-application, and use the Certification of fire resistant coating system.

• Journal of Surface Science and Engineering
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• v.48 no.6
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• pp.343-348
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• 2015

In this paper, arc Zn thermal spray coating was carried out on the SS400 steel, and then various electrochemical characteristics and surface damage behavior of Zn thermal spray coating layer were analyzed. As the results, the potential of Zn thermal spray coating layer presented driving voltage above 300 mV compare to that of SS400 steel. The passivity characteristic in anodic polarization curve was not presented. It was adequate to as sacrificial anode material. In the surface damage after galvanostatic experiments, uniform corrosion tendency of Zn thermal spray coating layer was clearly observed with acceleration of the dissolution reaction. In conclusion, Zn thermal spray coating could be determined to represent the corrosion protection effect by stable sacrificial anodic cathodic protection method in seawater because it had sufficient driving voltage and uniform corrosion damage tendency for the SS400 steel.