• Journal of the Korean Society of Food Culture
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• v.16 no.2
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• pp.170-179
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• 2001

Green Tea consists of 15-30% catechins (a type of polyphenol), which act as super antioxidants, inhibitory action against aging process. Antioxidants fight radical-free oxygen, an agent which can begin the process of cancer by damaging essential body chemicals and harming DNA. This study was peformed to develop the elderly diet using Green Tea as an inhibitory action against aging process. Nokchaborijook (Baley gruel added rice powder and Green Tea) was manufactured by various levels of Green Tea(1, 4, 7%) and the grinding period(15, 30, 45 sec). The optimum levels of added Green Tea and grinding periods on Nokchaborijook were determined with the results of sensory evaluation by response surface methodology and analysis of composition. The Anti-oxidant Vitamin A, C, E and Flavonoid were increased with increased levels of Green Tea and grinding periods be decreased. As the levels of Green Tea and grinding periods were increased, the green color and penetrated force became stronger. Among the sensory attributes, Bitterness, Green Tea Flavor and Hashness were greater depending on increasing Green Tea. Jujube flavor was greater relying on decreasing Green Tea. Greenness and spreadability of particles were increased as both the amounts of Green Tea and the grinding period were increased. This result was used to determine the optimum conditions of adding levels of Green Tea and grinding periods. The optimum conditions of Nokchaborijook was established as adding of 5.8% Green Tea grinded for 15 seconds.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.42 no.6
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• pp.545-554
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• 2009

This study was conducted to develop and characterize of a high quality salted mackerel using enzymatic extracts of Ecklonia cava (EEC). In this study, potential antioxidative properties of EEC were evaluated by DPPH free radical scavenging activity, hydrogen peroxide scavenging activity, peroxide value, and fatty acid composition, and the antimicrobial properties were also measured by analysis for volatile basic nitrogen, pH, viable cells, Eschericia coli and biogenic amine. Compared to EEC-untreated salted mackerel, the salted mackerel with EEC was superior in antioxidative properties, while was negligible in the difference of antimicrobial properties. These results suggested that the high quality salted mackerel with antioxidative activity could be developed by treatment of EEC.

• Knowledge Management Research
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• v.17 no.2
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• pp.27-50
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• 2016

Korean manufacturing industry have recently faced the catch-up of China in the mass commodity product, such as automotive, display, and smart phone in terms of market as well as technology. Accordingly, discussion on the importance of achieving catch-up in complex product systems (CoPS) has been increasing as a new innovation engine for the industry. In order to achieve successful catch-up of CoPS, we explored emerging technologies of CoPS, which are featured by the characteristics of radical novelty, relatively fast growth and self-sustaining, through the study of emerging technologies of gas turbine for power generation. We found that emerging technologies of the gas turbine are technologies for combustion nozzle and composition of electrical machine for increasing power efficiency, washing technology for particulate matter, cast and material processing technology for enhancing durability from fatigue, cooling technologies from extremely high temperature, interconnection operation technology between renewable energy and the gas turbine for flexibility in power generation, and big data technology for remote monitoring and diagnosis of the gas turbine. We also found that those emerging technologies resulted in technological progress of the gas turbine by converging with other conventional technologies in the gas turbine. It indicates that emerging technologies in CoPS can be appeared on various technological knowledge fields and have complementary relationship with conventional technologies for technology progress of CoPS. It also implies that latecomers need to pursue integrated learning that includes emerging technologies as well as conventional technologies rather than independent learning related to emerging technologies for successful catch-up of CoPS. Our findings provide an important initial theoretical ground for investigating the emerging technologies and their characteristics in CoPS as well as recognizing knowledge management strategy for successful catch-up of latecomers. Our findings also contribute to the policy development of the CoPS from the perspective of innovation strategy and knowledge management.

• Journal of the Korean Society of Combustion
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• v.7 no.1
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• pp.15-22
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• 2002

Flame spread experiments of a fuel droplet array were performed using a microgravity environment. N-decane, 1-octadecene, and the blends (50% : 50% vol.) of these fuels were used and the experiments were conducted at pressures up to 5.0 MPa, which are over the critical pressure of these fuels. Observations of the flame spread phenomenon were conducted for OH radical emission images recorded using a high-speed video camera. The flame spread rates were calculated based on the time history of the spreading forehead of the OH emission images. The flame spread rate of the n-decane droplet-array decreased with pressure and had its minimum at a pressure around half of the critical pressure and then increased again with pressure. It had its maximum at a pressure over the critical pressure and then decreased gradually. The pressure dependence of flame spread rate of 1-octadecene were similar to those of n-decan, but the magnitude of the spread rate was much smaller than that of n-decane. The variation of the flame spread for the blended fuel was similar to that of n-decane in the pressure range from atmospheric pressure to near the critical pressure of the blended fuel. When the pressure increased further, it approached to that of 1-octadecene. Numerically estimated gas-liquid equilibrium states proved that almost all the fuel gas which evaporated from the droplet at ordinary pressure consisted of n-decane whereas near and over the critical pressure, the composition of the fuel gas was almost the same as that of the liquid phase, so that the effects of 1-octadecene on the flame spread rate was significant.

• The Korean Journal of Food And Nutrition
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• v.30 no.3
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• pp.568-577
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• 2017

Vegetables and fruits contain a great deal of vitamins, minerals, dietary fiber and phytochemicals. Therefore, healthconcious consumer prefer beverage made from fresh fruits and vegetables due to their health benefits. This study was conducted to investigate differences in nutritional composition and sensory characteristics of juices depending on the apparatus used: either a low-speed juicer or high-speed blender. All ingredients could be made into juice without addition of water using the low speed juicer. However, addition of water was necessary to produce juice with the high-speed blender. Phenol and flavonoid content, were higher in juice made with the low-speed juicer than that produced with the high-speed blender and were correlated with DPPH radical scavenging ability. Protease activity of pineapples juices was not significantly different for the two methods, but protease activity of kiwi juice was about 8 times higher in juice made with low-speed juicer than that made with the high-speed blender. SOD activity also tended to be higher in the juice made with low-speed juicer. The concentration of dissolved oxygen in the juice made with high-speed blender was higher than that of juice made with a low-speed juicer and was correlated with color change. In addition, the high-speed blender caused an increase juice temperature, but temperature was not changed during use of the low-speed juicer. The noise level of the low-speed juicer was low, but the high-speed blender had high noise intensity comparable to that of railway or aircraft noise. In the sensory evaluation of juice, juice made with the low-speed juicer was preferred over juice made with the high-speed blender. As a result, the overall quality of the juice produced using the low-speed juicer was superior.

• Journal of the Korean Society of Safety
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• v.33 no.1
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• pp.41-46
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• 2018

Experiments were carried out the phenomenal observation on effect of corona treated hotmelt laminating film in process of manufacture by 2 kinds of rolling speed and electric power variatons. Surface treatment by corona which is exposure of film surface to electron of ion bombardment, rather than mere exposure to active species, like atomic oxygen or ozone, can enhance adhesion by removing contaminant, electret, roughening surface, and introducing reactive chemical group. Reactive neutrals, ions, electron and photons generated during the corona treatment interact simultaneously with polymers to alter surface chemical composition, wettability, and thus film adhesion. However, it is highly recommended that extensive chains scission is avoided because it can lead to side-effect by forming sticky matter, resulting in dropouts. This paper reviews principles of surface preparation of polypropylene substrate by corona discharging. In addition, the experimental section provides a description of parameter optimization on corona discharging treatment and its side-effect. Experimental results are discussed in terms of surface wetting as determined by contact angle and SEM measurements. When the rolling speed of the film decreased from 1.666 [m / sec] to 0.083 [m / sec], contact angle decreased from $80[^{\circ}]$ to $64[^{\circ}]$, and the wettability was greatly improved. As the supply power increased from 0.4 [kVA] to 2 [kVA] at the corona discharge surface treatment, the contact angle decreased from $77[^{\circ}]$ to $65[^{\circ}]$, and the wettability was greatly improved.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.44 no.1
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• pp.1-7
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• 2011

This study examined Tetraselmis sp. JK-46 isolated from seawater from the East Sea. Deep seawater (DSW) had a greater effect on the growth of Tetraselmis sp. JK-46 than surface seawater (SSW). The crude protein, lipid, carbohydrate and ash contents of Tetraselmis sp. JK-46 cultured with DSW were 27.2, 37.1, 13.2 and 26.3 %, respectively, and these values were similar to the results for samples cultured with SSW. The contents of Mg, Ca, Fe and K in the DSW cultured samples were 7080.3, 1009.6, 251.2, and 2749.7 mg/100 g, respectively. The fatty acid compositions of Tetraselmis sp. JK-46 cultured with DSW and SSW were 53.7 and 49.0 % polyunsaturated fatty acids (PUFA) and 25.7 and 30.7 % saturated fatty acids (SFA), respectively. The total amino acid contents of the samples cultured with DSW and SSW were 7392.6 and 6376.0 mg/100 g respectively. The 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity of Tetraselmis sp. JK-46 extracts increased with the concentration of the chloroform and ethyl acetate fractions. The half maximal inhibitiory concentrations ($IC_{50}$) of the chloroform and ethyl acetate fractions of DSW and SSW cultured samples were 1.2 and 2.6 mg/mL, and 3.1 and 3.3 mg/mL, respectively. The ethyl acetate fractions of DSW and SSW cultured samples has anticoagulant activity and the activated partial thromboplastin times (APTT) were 93.4 and 89.3 sec., respectively. The chloroform and ethyl acetate fractions showed antimicrobial activity against Bacillus subtilis, Escherichia coli and Candida albicans.

• Journal of Korean Society for Atmospheric Environment
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• v.19 no.E3
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• pp.137-148
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• 2003

In this study, we examined the influence of long-range transport of dust particles and air pollutants on the photochemistry of NO$_3$on Jeju Island, Korea (33.17 N, 126.10$^{\circ}$E) during the Asian Dust-Storm (ADS) period of April 2001. Three ADS events were observed during the periods of 10∼12, 13∼14, and 25∼26 April. Average concentration level of nighttime NO$_3$on Jeju Island during the ADS period was estimated to be about 2 x 10$^{8}$ molecules cm$^{-3}$ ( - 9 pptv). Decreases in NO$_3$levels during the ADS period was likely to be determined mainly by the enhancement of the $N_2$O$_{5}$ heterogeneous reaction on dust aerosol surfaces. The reaction of N20s on aerosol surfaces was a more important sink for nighttime N03 during the ADS due to the significant loading of dust particles. The reaction of $N_2$O$_{5}$ with NMHCs and the gas-phase reaction of N20s with water vapor were both significant loss mechanisms during the study period, especially during the NADS. However, dry deposition of these oxidized nitrogen species and a heterogeneous reaction of NO$_3$were of no importance. Short-term observations of $O_3$, NO$_2$, DMS, and SO$_2$in the MBL indicated that concentrations of most of these chemical species were different between the ADS and non - Asian - Dust-Storm (NADS) periods, implying that their levels were affected sensitively by the differences in air mass trajectories.

• Journal of the Korean Society of Food Culture
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• v.28 no.5
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• pp.512-524
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• 2013

The purpose of this study was to investigate the antioxidative effects of Mori Cortex Radicis powder and to determine the optimal mixing ratio of Mori Cortex Radicis powder and water in the preparation of bread. The optimal sensory composite recipe was determined by producing bread with different levels of Mori Cortex Radicis powder and water. The analysis was performed using response surface methodology and a sensory evaluation was performed with the data. Ten experimental recipes, including two with reference points in the composition, were selected. In terms of the antioxidative effects of Mori Cortex Radicis powder, the $IC_{50}$ for total phenolic content and DPPH free radical scavenging activity were 149.56 GAE/g dry powder and 137.77 /mL respectively. Measurement results of the mechanical properties showed differences in volume (p<0.05), baking loss (p<0.05), yellowness (p<0.01), lightness (p<0.01), redness (p<0.01), hardness (p<0.01) and springiness (p<0.05). The sensory measurements showed significant values for color (p<0.05), appearance (p<0.05), flavor (p<0.01), taste (p<0.01), and overall quality (p<0.01). Overall, based on numerical and graphical methods, the optimal formulation was determined to be 21.16 g of Mori Cortex Radicis powder and 372.47 g of water.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.7
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• pp.896-902
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• 2017

In this study, we investigated citrus Kombucha (CK) produced by three different bacteria strains (Gluconacetobacter xylinus, Gluconacetobacter medellinensis, and Gluconobacter oxydans; named as CK-MOX) identified from traditional Kombucha. During fermentation, the pH level of CK-MOX was gradually reduced, and total acidity slightly increased. Antioxidant activity, measured by DPPH, ABTS, and oxygen radical absorbance capacity assays, markedly increased after fermentation. Moreover, fermented CK-MOX (Day15) exhibited anti-proliferative and anti-migratory activities against EJ human bladder carcinoma cells. Western immunoblot assays showed that treatment with CK-MOX significantly up-regulated phospho-extracellular signaling kinase (ERK) levels. To distinguish whether or not up-regulation of phospho-ERK is the cause or effect, we investigated the viability of EJ cells in the presence of U0126, a mitogen activated protein kinase/ERK kinase 1/2 inhibitor. Pre-treatment with U0126 rescued cells from CK-MOX-induced cell death, which indicates phospho-ERK may be a key regulator in the mechanism of CK-MOX-induced apoptosis of EJ bladder cancer cells. In conclusion, CK-MOX, fermented by a defined composition of bacterial starters, shows antioxidant capacity and anti-cancer activity against EJ bladder cancer cells.