• Magazine of the Korean Society of Agricultural Engineers
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• v.39 no.4
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• pp.114-121
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• 1997

In order to provide basic information for the estimation of evapotranspiration in the ponded direct seeding paddy field, both field lysimeter experiment and model prediction were performed to estimate daily ET. Various methods were used to predict daily reference crop ET and crop coefficients. Measure4 mean daily ET during the 1995 growing season varied from 5.9 to 6.1 mm depending on the species, while it varied from 5.1 to 5.5 mm in 1996. Model predicted mean daily ET during the 1995 growing season varied from 3.9 to 4.9 mm depending on the prediction model, while it varied from 3.5 to 4.7 mm in 1996. The smaller ET values both measured and predicted in 1996 were caused by the low values of temperature, sunshine hours, and solar radiation. Crop coefficients varied from 1.20 to 1.50 in 1995 depending on the prediction model, while it varied from 1.10 to 1.47 in 1996. Comparison of the seven reference crop ET prediction methods used in this study shows that the Penman-Monteith method and the FAO-Radiation method gave the lowest ET while the corrected Penman method and the Hargreaves method gave the largest ET. Since crop coefficients vary to a large extent based on the prediction methods, reference crop ET prediction method should be carefully selected in irrigation planning.

• Proceedings of the KSRS Conference
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• 2004.10a
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• pp.162-165
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• 2004

The authors' previous study found an interannual covariability between actual evapotranspiration (ET) and the Normalized Difference Vegetation Index (NDVI) over northern Asia. This result suggested that vegetation controls interannual variation in ET. In this prior study, NDVI data from the Pathfinder AVHRR Land (PAL) dataset were analyzed. However, studies of NDVI interannual change are subject to uncertainty, because NDVI data often contain errors associated with sensor- and atmosphere-related effects. This study is aimed toward reducing this uncertainty by employing NDVI dataset, from the Global Inventory Monitoring and Modeling Studies (GIMMS) group, in addition to PAL. The analysis was carried out for the northern Asia region from 1982 to 2000. 19-year interannual change in PAL-NDVI and GIMMS-NDVI were both compared with interannual change in model-assimilated ET. Although the correlation coefficient between GIMMS-NDVI and ET is slightly less than for PAL-NDVI and ET, for both NDVI datasets the annual maximum correlation with ET occurs in June, which is near the central period of the growing season. A significant positive correlation between GIMMS-NDVI and ET was observed over most of the vegetated land area in June as well as PAL-NDVI and ET. These results reinforce the authors' prior research that indicates the control of interannual change in ET is dominated by interannual change in vegetation activity.

• Nuclear Engineering and Technology
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• v.45 no.6
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• pp.707-720
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• 2013

We analyze piecewise homogenization with flux-weighted cross sections and preservation of averaged currents at the boundary of the homogenized domain. Introduction of a set of flux discontinuity ratios (FDR) that preserve reference interface currents leads to preservation of averaged region reaction rates and fluxes. We consider the class of numerical discretizations with one degree of freedom per volume and per surface and prove that when the homogenization and computing meshes are equal there is a unique solution for the FDRs which exactly preserve interface currents. For diffusion submeshing we introduce a Jacobian-Free Newton-Krylov method and for all cases considered obtain an 'exact' numerical solution (eight digits for the interface currents). The homogenization is completed by extending the familiar full assembly homogenization via flux discontinuity factors to the sides of regions laying on the boundary of the piecewise homogenized domain. Finally, for the familiar nodal discretization we numerically find that the FDRs obtained with no submesh (nearly at no cost) can be effectively used for whole-core diffusion calculations with submesh. This is not the case, however, for cell-centered finite differences.

• Food Science and Biotechnology
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• v.18 no.6
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• pp.1476-1480
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• 2009

Antioxidant activities of mulberry leaf extracted with different concentrations of EtOH were investigated. Total phenolic content and electron donating abilities of extract from 70% EtOH were the highest. Extracts obtained from EtOH-water mixture were shown to be significantly higher superoxide dismutase (SOD)-like activities than other treatment (p<0.05). Angiotensin-converting enzyme (ACE) inhibition was the greatest at 50% EtOH concentration (p<0.05). The extracts from 30-70% EtOH exhibited higher ferric reducing ability of plasma (FRAP) value than rest of the concentration (p<0.05). In case of nitrite scavenging activity, much higher scavenging activities were observed when the extraction was performed with EtOH or EtOH-water mixture (p<0.05). The results indicate that concentration of EtOH as extraction solvents can affect the antioxidant activity of mulberry leaf, which may provide useful information on the optimal solvent conditions for the extraction.

• Journal of the East Asian Society of Dietary Life
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• v.21 no.2
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• pp.228-234
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• 2011

This study investigated the anti-oxidation activities of fresh Codonopsis lanceolata Traut (Benth et Hook) and red beans, and also the quality properties of fresh Codonopsis lanceolata Yanggaeng to which raw Codonopsis lanceolata Traut (Benth et Hook) was added. The DPPH free radical scavenging activities of fresh Codonopsis lanceolata Traut (Benth et Hook) and red beans were 31.42% and 37.98%, respectively. Thus, that of red beans was rather the total polyphenol contents of fresh Codonopsis lanceolata Traut (Benth et Hook) and red beans were 5.74 mg/g and 4.14 mg/g respectively, and the total flavonoid contents of fresh Codonopsis lanceolata Traut (Benth et Hook) and red beans were 5.07 mg/g and 1.29 mg/g respectively. As higher amounts of Codonopsis lanceolata Traut (Benth et Hook) were added to Yanggaeng, the water content in the Yanggaeng continued to increase. Preferences were in the following order: 21%>12%>28%>7%>0%, and it was found that the optimal level for addition of fresh Codonopsis lanceolata Traut (Benth et Hook) was between 12% and 21%. It was also shown that adjusting the amount of ingredients or agar would improve the product quality.

• Journal of Korea Society of Digital Industry and Information Management
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• v.14 no.4
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• pp.125-134
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• 2018

Lamport firstly suggested password base authentication scheme and then, similar authentication schemes have been studied. Due to the development of Internet network technology, remote user authentication using smart card has been studied. Li et al. analyzed authentication scheme of Chen et al. and then, Li et al. found out the security weakness of Chen et al.'s scheme such forward secrecy and the wrong password login problem, and proposed an a new smart card based user password authentication scheme. But Liu et al. found out that Li et al.'s scheme still had security problems such an insider attack and man-in-the-middle attack and then Liu et al. proposed an efficient and secure smart card based password authentication scheme. This paper analyzed Liu et al.'s authentication and found out that Liu et al.'s authentication has security weakness such as no perfect forward secrecy, off-line password guessing attack, smart-card loss attack, and no anonymity. And then, this paper proposed security enhanced efficient smart card based password authentication scheme using fuzzy extraction technology.

• Journal of Applied Biological Chemistry
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• v.60 no.1
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• pp.5-11
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• 2017

18 flowers of Compositae family were collected and extracted in aqueous methanol (MeOH). The concentrated extract was partitioned into n-hexane, ethyl acetate (EtOAc), n-BuOH, and water fractions. The extract and fractions were evaluated for total phenolics, total flavonoids, 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity, and tyrosinase inhibition activity. n-Hexane and EtOAc fractions of Aster yomena, n-hexane fraction of Cosmos bipinnatus White, n-hexane and EtOAc fractions of C. bipinnatus Pink showed high total phenolics. And EtOAc fractions of A. yomena, C. bipinnatus White, C. bipinnatus Red, C. morifolium Froggy, and C. morifolium Himaya exhibited high total flavonoids. EtOAc fractions of A. yomena, C. bipinnatus White, C. bipinnatus Pink, C. morifolium Yellowmable, and MeOH extract of C. morifolium Rosa significantly scavenged DPPH radical. EtOAc fractions of C. chinensis, C. bipinnatus White, C. bipinnatus Red, C. morifolium Himaya, and C. morifolium Hongsim highly inhibited the tyrosinase activity. A. yomena, C. bipinnatus White, C. bipinnatus Pink, C. bipinnatus Red and C. morifolium Himaya are evaluated as good source for whitening cosmetics materials.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.10
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• pp.1336-1342
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• 2006

This study was performed to investigate the effect of ethanol extract of Chaenomeles sinensis Koehne (CS) on alcohol-induced liver damage in rats. Male Sprague-Dawley rats weighing $135{\pm}10g$ were divided into 6 groups for 4 weeks; normal group (ND), alcohol (35%, 10 mL/kg/day) treated group (ET), CS ethanol extract 200 mg/kg/day treated group (ND-CSL), CS ethanol extract 400 mg/kg/day treated group (ND-CSH), CS ethanol extract 200 mg/kg/day and alcohol treated group (ET-CSL), and CS ethanol extract 400 mg/kg/day and alcohol treated group (ET-CSH). The body weight gain and food efficiency ratio were no differences between ND and ET. There were increases in the activities of serum alanine aminotransferase (ALT), asparate aminotransferase (AST), and alkaline phosphatase (ALP) in ET. On the other hand, the administration of CS decreased ALT, AST and ALP activities in serum. It was also observed that the hepatic activities of superoxide dismutase (SOD), catalase, glutathione peroxidase (GSH-Px) and xanthine oxidase (XO) increased by alcohol treatment were also markedly decreased in the CS administered groups as compared with ET. The activities of hepatic SOD, catalase, GSH-Px and XO were riot significantly different among the normal diet groups. Contents of thiobarbituric acid reactive substances (TBARS) were increased by the administration of alcohol, on the other hand, the administration of CS reduced TBARS value in the liver. In addition, the content of glutathione (GSH) in the liver was decreased by alcohol administration, however, GSH increased after administering CS. In conclusion, the administration of alcohol develops the hyperoxidation of liver lipids through tile increase in enzymes activity related to the lipid peroxiation, however, it was decreased after administring CS. Thus, CS may have a possible protective effect on ethanol-induced hepatotoxicity in rat liver.

• The Korean Journal of Pharmacology
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• v.28 no.1
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• pp.49-60
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• 1992

This study was designed to evaluate the responses of cardiovascular system to endothelin (ET) and neuropeptide Y (NPY) in 12 week-old SHR treated with or without enalapril (ENP) for 6 weeks. The diastolic blood pressure and heart rate were lower in ENP-treated SHR than in control. The pressor response to intravenous, but not intracerebroventricular, ET or NPY was attenuated by ENP treatment. The chronotropic action induced by electrical stimulation was attenuated by ENP or ET. The negative chronotropic action of ET was blocked by yohimbine. The increase in aortic tension induced by electrical field stimulation (EFS) was depressed in ENP-treated group as compared with non-treated group, and enhanced by ET, but not NPY, in the non-treated group. The ET-induced increase in tension was enhanced by removal of endothelium in the control group but not in ENP-treated group. The plasma concentration of norepinephrine and ET-induced increase in concentration of norepinephrine and epinephrine in plasma were decreased in ENP-treated group. These results suggest that preventive effect of enalapril on the development of hypertension may result from depressing vasoactive action of endothelin and neuropeptide Y, and sympathetic neurotransmission at peripheral nervous system.

• Journal of Life Science
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• v.29 no.1
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• pp.69-75
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• 2019

Rosemary (Rosmarinus officinalis L.) is widely used as a food material. Although various physiological activities of rosemary have been reported, there have been no studies on the physiological activity of solvent extracts with different polarities. Rosemary extracts were obtained by extraction of dried powder using 0%, 25%, 50%, 70%, and 95% ethanol (EtOH) in distilled water, methanol, ethyl acetate, and hexane. As these ratios of EtOH are generally chosen by default and scarcely optimized, we investigated the impact of the composition of EtOH in distilled water on extract-related characteristics, such as DPPH free radical scavenging and ${\alpha}$-glucosidase inhibition, on the differentiation of 3T3-L1 adipocytes and inhibition of tyrosinase. Adipogenesis inhibition was highest at 70% EtOH. DPPH scavenging activity and inhibition of tyrosinase activity were reduced with 50% EtOH in water. However, inhibition of ${\alpha}$-glucosidase activity was higher in 50% EtOH in water. The best solvents in terms of DPPH scavenging activity, inhibition of tyrosinase and ${\alpha}$-glucosidase, and differentiation of adipocytes obtained with different concentrations of EtOH, although a lower similar activities were found with 50% ethanol. Considering the extraction solvents, a ratio of EtOH in water gives different content and constituents of compounds. These differences will give activities inhibition of adipogenesis, tyrosinase, ${\alpha}$-glucosidase activity, and DPPH scavenging activity.