• The KSFM Journal of Fluid Machinery
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• v.12 no.3
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• pp.19-25
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• 2009

InThe purpose of this work is to analyze the flow characteristics and aerodynamic noise generated from a shroud fan at a constant 2,100 rpm using LES and FW-H noise model provided in the commercial code, FLUENT. Velocity distributions around the shroud fan obtained by using FLUENT code show good agreement with experimental results. The sound pressure level is decreased by about 6 dB as the distance from the fan increases twice. The directivity at 1st BPF shows a tendency of increasing SPL toward the axis of rotation.

• The Korean Journal of Ecology
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• v.15 no.4
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• pp.377-386
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• 1992

Seasonal changes of symbiotic nitrogen-fixation activity and growth characteristics of four different natural populations of kummerowia striata were quantitatively analyzed during the growing period. the nitrogen-fixation activity of root nodules attained the maximum rates of 148, 132, 102 and 100$\muM\;C_2H_4\;\cdot\;g\;fw\;nodule^{-1}\;\cdot\;hr^{-1}$, respectively for sunny, multibranched, shade and unibranched populations at the optimum growth conditions. and the seasonal changes showed fluctuations by environmental conditions such as light, temperature, nutrient contents, water stress and plant ages, etc. The multibranched plant showed the greater amount of leaf and root nodule biomass, and the higher nitrogenase activity than the unibranched plant. the optimum conditions of leaf chloropht11 and water content of each organ indicated the active growth and the maximum fresh biomass of 4 different populations were 1.92, 1.85, 0.97 and 0.56 g $fw\cdotplant^{-1}$ for shade multibranched, sunny and unibranched populations, respectively.

• Food Science and Biotechnology
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• v.16 no.5
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• pp.802-806
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• 2007

There has been growing interest in the antioxidative and anticarcinogenic effects of vegetables. This study was aimed at evaluating the antioxidative and antiproliferative activities of 13 leafy vegetables consumed in Korea. New-beet and ornamental kale contained >1,000 mg of polyphenolics/100g fresh weight (FW), which was the greatest amount among the test vegetable extracts. Ornamental kale also contained the greatest amount (232.84 mg/100g FW) of flavonoids. With the exception of chicory, values of 1.1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) radical scavenging activities showed similar trends. New-beet was found to be the greatest antioxidant among the test vegetable extracts. New-beet exhibited the highest antiproliferative activity (>60%) against all tumor cells. No relationship was found between antiproliferative activity and antioxidant contents or antioxidant activities among samples.

• Proceedings of the KSME Conference
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• 2000.11b
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• pp.502-507
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• 2000

This paper presents the numerical prediction of airflow-induced sound in DVD drives. Computational fluid dynamics (CFD) is first conducted to evaluate flow field characteristics due to the high-speed disk rotation, and to support the acoustic analysis. The acoustic analogy based on Ffowcs Williams-Hawkings (FW-H) equation is adopted to predict aeroacoustic noise patterns. The integral solution for quadrupole volume source is included to identify the turbulence noise generated inside the DVD tray. Near-field noise is strongly affected by the flow field characteristic, which is caused by the complex shape of the tray. For a mid-field, the quadrupole noise play as a counterpart of thickness noise or loading noise, resulting in a different pattern compared with those in the near field.

• Proceedings of the KSME Conference
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• 2002.08a
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• pp.763-766
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• 2002

A BEM is highly efficient method in the sense of economic computation. However, boundary integration is not easy for the complex and moving surface e.g. in a rotating blade. Thus, Kirchhoff surface is designed in an effort to overcome the difficulty resulting from complex boundary conditions. A Kirchhoff surface is a fictitious surface which envelopes acoustic sources of main concern. Acoustic sources may be distributed on each Kirchhoff surface element depending on its acoustic characteristics. In this study, an axial fan is assumed to have loading noise as a dominant source. Dipole sources can be computed based on the FW-H equation. Acoustic field is then computed by changing Kirchhoff surface on which near-field is implemented, to analyze the effect of Kirchhoff surface on it.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2002.05a
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• pp.772-777
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• 2002

A BEM is highly efficient method in the sense of economic computation. However, boundary integration is not easy for the complex and moving surface e.g. in a rotating blade. Thus, Kirchhoff surface is designed in an effort to overcome the difficulty resulting from complex boundary conditions. A Kirchhoff surface is a fictitious surface which envelopes acoustic sources of main concern. Acoustic sources may be distributed on each Kirchhoff surface element depending on its acoustic characteristics. In this study, an axial fan is assumed to have loading noise as a dominant source. Dipole sources can be computed based on the FW-H equation. Acoustic field is then computed by changing Kirchhoff surfaces on which near-field is implemented, to analyze the effect of Kirchhoff surface on it.

• Korean Journal of Plant Resources
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• v.19 no.3
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• pp.381-384
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• 2006

This study was conducted to selected Korean black raspberry (Rubus coreanus Miq.) for high productivity. The eight major agronomic traits were investigated from 198 clones of the clone bank established in Korea Forest Research Institute, Suwon, Korea. The selection levels based on number of fruit per fructify lateral (NFFL) over 20, and fruit weight (FW) over 1.3g, and yield of individual per fructify lateral (YIFL) over 25g, were applied on 198 clones, resulted in 17 clones selected. The selected superior trees, 17 clones, appeared regional differences for amount of fruiting among 4 different test sites. When number of fruit per fruit petiole (NRFP), fruit weight (FW), yield of individual (YI) and sugar content were satisfied over 20, 1.4g, 6kg and 9.5 brix, respectively, as a select condition, 5 clones were reselected as the superior trees among 17 clones. for 3 years.

• Korean Journal of Food Science and Technology
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• v.51 no.3
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• pp.207-213
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• 2019

This study was conducted to investigate the antioxidant contents and activities of twelve vegetable sprouts (broccoli, red radish, radish, mizuna, kale, taatsai, pak choi, Chinese cabbage, turnip, rapeseed, chicory, and alfalfa). The total flavonoid contents of the broccoli, red radish, and radish sprout were $25.36{\pm}0.13$, $25.26{\pm}1.80$, and $25.16{\pm}1.25mg$ CE/100 g FW, respectively, and were significantly higher than those of the other tested vegetables. Radish sprouts had the highest total phenolic content (112.42 mg GAE/100 g FW), followed by red radish and broccoli sprouts. The main polyphenols in the vegetable sprouts were epicatechin and chlorogenic acid, but they varied across sprout varieties. The correlation between total flavonoids and total phenolics for the 12 vegetable sprouts was very high (r=0.926). The total antioxidant activity (DPPH and ABTS radical scavenging activities) was also highly correlated with total flavonoids and total phenolics.

• Korean Journal of Food Science and Technology
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• v.52 no.6
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• pp.604-609
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• 2020

This study analyzed the antioxidant contents and activities of the pedicel and sepals from 12 colored cherry tomatoes ('Green Joy', 'TY Item', 'Dotori Red TY', 'TY Sispen', 'KT Orange TY', 'White Joy TY', 'Dotori Norang TY', 'Beta Tiny', 'Blacklin', 'KT Red TY', 'KT Norang TY', 'Black Joy 200') for their potential use as bioactive ingredients. 'Green Joy' had a significantly higher content of total flavonoids (92.55±3.20 mg CE/100 g FW), total phenolics (261.94±8.32 mg GAE/100 g FW), and total antioxidant activity than the other varieties. The main polyphenols were rutin, chlorogenic acid, and methyl gallate. For all 12 samples, the total flavonoids content was highly correlated with the total phenolics content and the total antioxidant activities. Non-edible parts of cherry tomato have high potential as functional food materials because they contain similar or more antioxidants and antioxidant properties than the pulp of tomato and cherry tomato or other fruits.

• Proceedings of the KWS Conference
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• 2001.05a
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• pp.122-124
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• 2001