• Journal of Ocean Engineering and Technology
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• v.23 no.5
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• pp.9-14
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• 2009

The green water on deck has many harmful effects on the vessel in rough seas such as damages to hull structures, damages to cargos, increase of the downtime, decrease of the stability, and so on. Floating Production Storage and Offloading vessels (FPSOs) are operated in a specific location and are normally positioned to meet mostly head or bow waves in order to reduce the roll motions. But this makes FPSOs more vulnerable to green water around the bow region therefore the bow shape should be properly designed to mitigate the green water damage. In this paper, experimental results in regular head waves for three kinds of bow shapes are compared and some design considerations are proposed, with the building a database for computational fluid dynamics (CFD) validation in mind.

• Journal of the Society of Naval Architects of Korea
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• v.50 no.5
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• pp.273-281
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• 2013

In this paper, the effects of bow deck shape on the green water are studied by numerical and experimental method. Varying the deck shapes to triangular, elliptic and circular, the thickness and advancing velocity of green water leading edge are compared using numerical method. Also the motion, the pressure on the vertical wall and the height on the deck of green water are compared among the three bow deck shapes in the heave and pitch motion free condition by experimental method. To remove the effects of the difference of motions among the deck shapes, numerical simulations are performed varying the deck shape with the same motion. In the same motion condition, smallest impulsive pressure occurred in the condition of elliptic deck shape.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.16 no.12
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• pp.1211-1218
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• 1991

The under water communication which use blue green lasers reviewed. In the view point of absorption and scattering, the optical characteristics of sea water are described. In addition, state of blue green lasers for under water communication are summarized.

• Korean journal of food and cookery science
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• v.15 no.3
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• pp.216-223
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• 1999

The purpose of this study is to find out the optimal mixing ratios of three different amounts of green tea powder, sugar and water for preparation of Sulgiduk through Response Surface Methodology based on the color, sensory, and texture test. The green tea powder levels were included 0.5∼1.0%, water levels were included 15∼25% and sugar levels were included 5∼15% per weight of rice powder. The optimal mixing ratios of a green tea powder, sugar and water for manufacturing the best quality of Sulgiduk were 1.0%, 12% and 22%, respectively.

• Journal of the Korean Home Economics Association
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• v.25 no.1
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• pp.51-58
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• 1987

This study was undertaken to investigate changes in blood pressure and heart rate in normal cats by administration of Korean native green tea. The chemical components of Korean native green tea which determined are water(2.2%), water extract(32.7%), vitamin C(480%), caffeine(2.6%), tannin(32.7%) and amino acid of water soluble content 5.8%. Effect on blood pressure in administration 100mg/kg, 300mg/kg, 500mg/kg of extract of green tea, the mean depressor response is 44.8$\pm$3.3mmHg, 60.5$\pm$3.6mmHg, and 65.0$\pm$3.3mmHg in normal cats. Effect on heart rate in administration 100mg/kg, 300mg/kg of extract of Korean native green tea, the mean decreased heart rate is 2.8$\pm$4.5 beats/min, 15.2$\pm$6.4beats/min and 19.1$\pm$4.0 beats/min.

• Proceedings of the Korea Water Resources Association Conference
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• 2016.05a
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• pp.192-192
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• 2016

Nowadays, stormwaters have been affected by urbanization and climate change. These transition can cause many problems for hydrologic cycle by increasing runoff volume like flood and low water quality. As with other metropolises and peninsulas, Busan has involved with these problems too. Therefore, it is really vital to do some arrangements to solve them by low impact development (LID) technology. In fact, LID has been introduced to reduce runoff by applying some techniques such as green infrastructure (GI). In order to deal with the aforementioned issues in Busan, this study attempts to design and construct a hybrid green roof-planter box system at Pusan National University GI/LID Facility based on local weather. For this purpose, we used experiment and modeling method on some planter boxes and optimized them by trial and error method.

• Journal of Electrochemical Science and Technology
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• v.12 no.3
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• pp.302-307
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• 2021

Polymer electrolyte membrane (PEM) electrolyzer or alkaline electrolyzer is required to produce green hydrogen using renewable energy such as wind and/or solar power. PEM and alkaline electrolyzer differ in many ways, instantly basic materials, system configuration, and operation characteristics are different. Building an optimal water hydrolysis system by closely grasping the characteristics of each type of electrolyzer is of great help in building a safe hydrogen ecosystem as well as the efficiency of green hydrogen production. In this study, the basic operation characteristics of a kW class alkaline water electrolyzer we developed, and water electrolysis efficiency are described. Finally, a brief overview of the characteristics of PEM and alkaline electrolyzer for large-capacity green hydrogen production system will be outlined.

• Journal of Environmental Science International
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• v.24 no.4
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• pp.541-547
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• 2015

Formation of disinfection by-products (DBPs) including trihalomethans (THMs) and haloacetic acids (HAAs) from chlorination of six different species (Chlorella vulgaris, Scenedesmus sp., Anabaena cylindrical, Microcystis aeruginosa, Asterionella formosa and Aulacoseira sp.) of algal extracellular organic matter (EOM). The EOM characteristics evaluation of six algal species reaching at the stationary phase in the growth curve showed most of its SUVA254 showed below 1 and this means hydrophilic organic matter is much higher than hydrophobic organic matter. Chloroform formation potential (CFFP), dichloroacetic acid formation potential (DCAAFP) and trichloroacetic acid formation potential (TCAAFP) were mainly composed of THMFP and HAAFP in the EOM of various algal species. In the case of THMFP/DOC and HAAFP/DOC values, EOM of blue-green algae has appeared highest and EOM of green algae and diatom in order. THMFP/DOC was higher than HAAFP/DOC in EOM of blue-green algae. In comparison of formation potential by unit DOC composed of HAAFP in algal species EOM, DCAAFP/DOC was 1.5 times to 7.5 time higher than TCAAFP/DOC in the EOM of blue-green algae, while DCAAFP/DOC was found to be relatively high compared to TCAAFP/DOC in the EOM of green algae and diatom.

• Journal of Nutrition and Health
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• v.33 no.6
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• pp.632-638
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• 2000

This study was designed to observe the effect of green tea on colon tumor incidence and biomarkers of colon carcinogenesis in 1, 2-dimethlhydrazine-treated rats. Male Sprague Dawley rats at 7 weeks of age were divided into two groups: control and green tea(GT) groups. Control rats had distilled water as drinking water but GT group received green tea extracts(2.5%, w/v water) as drinking water throughout the experiment periods. All rats were fed the experimental diet containing 15% fat by weight for 20 weeks. and were i.m. injected with DMH for 6 weeks to give total dose of 180mg/kg body weight. Tumor incidence was reduced in GT group (39%) compared with control group (56%) Green tea significantly reduced cell proliferation (total cells per crypt, crypt length and proliferative zone) in colonic mucosa and also significantly reduced the levels of preformed prostalandin E2(PGE2) and thromboxance B2(TXB2) in colonic mucosa but the fatty acid profile of total lipid in colonic mucosa was not significantly influenced by green tea. However the relative percent of C20:4 and the levels f preformed PGE2 and TXB2. were significantly higher in tumor tissue compared with normal surrounding mucosa.Green tea increased the fecal excretion of total bile acid but not scondary bile acid which is known as one of promoters for colon cancer,. These results suggest that green tea could have preventive effect against colon cancer when consumed daily by influencing on antioxidant effect and the metabolism of arachidonic acid.

• Korean journal of food and cookery science
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• v.28 no.3
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• pp.319-326
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• 2012

This study was designed to investigate the properties related to browning of hot water and 80% ethanol extracts of green tea (Camellia sinensis) and propolis. The extracts were assessed for polyphenol oxidase (PPO) inhibitory activity and total phenolic and flavonoid contents. In addition, apples were cut into 15 mm thick slices and dipped for 1 min in 0.5% of the green tea extracts and the propolis solutions and stored at room temperature for 24 h. The PPO inhibitory activity of the green tea extracts was better than that of the propolis. The highest DPPH free radical scavenging activity (90.81%), total phenol contents (170.42 mg/mL) and the metal chelating effects (45.93%) were measured in the green tea hot water extracts. The mineral content of the green tea water extracts was 69,328.44 ppm potassium and 2,409.42 ppm magnesium. After 24 h, the ${\Delta}E$ value of the apple slices treated with the green tea water extracts was the lowest (1.35). The antibrowning effects of the green tea extracts were higher than those of propolis in the apple slices.