• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2005.05a
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• pp.283-286
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• 2005

Because CV Joint which is one of the component of automobile power train system communicates high power and performs power steering function, it requires high qualities such as high strength, high toughness and high fatigue resistance. This component undergoes a series of production processes such as forging, machining and heat treatment and required properties for this component depends on plastic deformation and heat treatment heavily. Therefore in this study, in order to these effects on mechanical properties due to plastic deformation and heat treatment we performed heat treatment following plastic deformation and then tensile test.

• Korean Journal of Remote Sensing
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• v.4 no.1
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• pp.49-60
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• 1988

Principal Component Analysis (PCA) was applied for regional geological mapping to a multivariate data set of the Landsat TM data in the heavily vegetated and topographically rugged Chungju area. The multivariate data set selection was made by statistical analysis based on the magnitude of regression of squares in multiple regression, and it includes R1/2/R3/4, R2/3, R5/7/R4/3, R1/2, R3/4. R4/3. AND R4/5. As a result of application of PCA, some of later principal components (in this study PC 3 and PC 5) are geologically more significant than earlier major components, PC 1 and PC 2 herein. The earlier two major components which comprise 96% of the total information of the data set, mainly represent reflectance of vegetation and topographic effects, while though the rest represent 3% of the total information which statistically indicates the information unstable, geological significance of PC3 and PC5 in the study implies that application of the technique in more favorable areas should lead to much better results.

• Journal of the Korean Statistical Society
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• v.30 no.4
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• pp.541-550
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• 2001

This paper considers a panel data regression model in which the disturbances follow a nested error components with serial correlation. Given this model, this paper derives several Lagrange Multiplier(LM) testis for the presence of serial correlation as well as random individual effects, nested effects, and for existence of serial correlation given random individual and nested effects.

• Journal of the Korean Statistical Society
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• v.9 no.1
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• pp.1-12
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• 1980

A parallel flats faraction for the $3^n$ factorial experiment is symbolically written as $At = C(r\timesf)$ where $A(r\timesn)$ is of rank r. The A-matrix partitions the nonnegligible effects into $(3^{n-r}-1)/2+1$ alias sets. The $U_i$ effects in the i-th alias set are related pairwise by elements from $S_3$, the symmetric group on three symbols. For each alias set the f flats produce an $f \times u_i$ alias componet permutation matrices (ACPM) with elements from $S_3$. All the information concerning the relationships among levels of the effects is contained in the ACPM.

• Korean journal of food and cookery science
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• v.24 no.1
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• pp.132-156
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• 2008

The basic effects of herbs and spices when applied during cooking include flavoring, pungency, coloring, and deodorizing/masking effects. Besides these basic effects, herbs and spices have antioxidant, antimicrobial, pharmaceutical, and nutritional properties. This review briefly describes the flavor component characteristics as well as biological functions of herbs and spices during cooking and processing, with specific focus on garlic and Brassica vegetables.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.19 no.1
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• pp.39-47
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• 2009

The effects of thermo-solutal convection on mercurous chloride system of ${Hg_2}{Cl_2}$, and Ne during physical vapor transport are numerically investigated for further understanding and insight into essence of transport phenomena, For $10\;K{\le}{\Delta}T{\le}30\;K$, the growth rate slowly increases and, then is decreased gradually until ${\Delta}T$=50 K, The occurrence of this critical point near at ${\Delta}T$=30 K is likely to be due to the effects of thermo-physical properties stronger than the temperature gradient corresponding to driving force for thermal convection. For the range of $10\;Torr{\le}P_B{\le}300\;Torr$, the rate is second order-exponentially decayed with partial pressures of component B, $P_B$. For the range of $5{\le}M_B{\le}200$, the rate is second order-exponentially decayed with a function of molecular weight of component B, $M_B$. Like the case of a partial pressure of component B, the effects of a molecular weight arc: reflected through the binary diffusivity coefficients, which are intimately related with suppressing the convection flow inside the growth enclosure, i,e., transition from convection to diffusion-dominant flow mode as the molecular weight of B increases. The convective mode is near at a ground level, i,e., on earth (1 $g_0$), and the convection is switched to the diffusion mode for $0.1\;g_0{\le}g{\le}10^{-2}g_0$, whereas the diffusion region ranges from $10^{-2}g_0$ up to $10^{-5}g_0$.

• Natural Product Sciences
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• v.15 no.4
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• pp.229-233
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• 2009

The essential oil fraction was obtained from the leaves and flowers of Artemisia iwayomogi (Compositae) by steam distillation, and its main component, vulgarone B, was isolated by column chromatography. RAW 264.7 cells were used to investigate the anti-inflammatory properties of A. iwayomogi and vulgarone B. Cell viability was determined by MTT assay after treatment with various dilutions of the compounds. In addition, several assays were used to determine the effects of A. iwayomogi essential oil components on immune stimulation. Nitric oxide production in cells activated with lipopolysaccharide (LPS) was evaluated by reaction with Griess reagent. Both vulgarone B and the essential oil fraction of A. iwayomogi inhibited the production of nitric oxide. The effects on various cytokines released from the cells were also measured using ELISA. The production of prostaglandin $E_2$ was significantly decreased by treatment with A. iwayomogi oils. LPS-induced IL-$1{\beta}$ and IL-6 production were also decreased in a dose-dependent manner, but no significant effect on TNF-${\alpha}$ was observed at the concentrations tested. Finally, Western blot analysis revealed that A. iwayomogi oils reduced the levels of COX-2 and iNOS.

• Natural Product Sciences
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• v.20 no.1
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• pp.33-38
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• 2014

In recent times, the demand for edible medication for the treatment of hyperpigmentation has increased significantly. Therefore, the discovery of a stable, safe and inexpansive antimelanogenic component from natural substances, such as grains, is of particular interest. The levels and activities of some metabolites and/or enzymes can be increased. In the present study, we investigated the antimelanogenic effects of water-soluble extracts from barley (BE), malt (ME) and germinated barley (GBE) in melan-a cells. The inhibitory effects of ME and GBE on melanin production were significantly greater than that of BE. Interestingly, the content of ferulic acid, the proposed active component of barley, was also higher in ME and GBE than in BE by HPLC analysis. Western blot analysis of the expression of melanogenic enzymes in melan-a cells treated with BE, ME or GBE indicated the expression of both tyrosinase and tyrosinase-related protein 2 (TRP-2) significantly decreased after treatment with BE, ME or GBE. These results suggest that besides BE, ME and GBE also inhibit melanin production most likely through suppression of tyrosinase and TRP-2 expression. ME and GBE were more efficacious at inhibiting melanin production than BE was and may also represent potential skin-whitening agents.

• Journal of Microbiology and Biotechnology
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• v.17 no.7
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• pp.1127-1133
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• 2007

Antihyperlipidemic and antihyperglycemic effects of Red Ginseng (RG, steamed and dried root of Panax ginseng C.A.Meyer, family Araliaceae), major component of which is ginsenoside Rg3, and Bifidodoterium-fermented RG (FRG), major component of which is ginsenoside Rh2, were investigated. Orally administered RG and FRG potently reduced the serum triglyceride levels in com-oil-induced hypertriglycemidemic mice as well as total cholesterol and triglyceride levels in Triton WR-1339-induced hyperlipidemic mice. Of the saponin and polysaccharide fractions of RG and FRG, the polysaccharide fraction inhibited postprandial blood glucose elevation of maltose- or starch-loaded mice and reduced the blood triglyceride levels in com-oil-induced hypertriglycemidemic mice. The saponin fraction and its ginsenosides Rg3 and Rh2 reduced blood triglyceride and total cholesterol levels in Triton WR1339-induced hyperlipidemic mice. The inhibitory effect of FRG and its main constituents against hyperlipidemia and hyperglycemia in mice were more potent than those of RG. These findings suggest that hypolipidemic and hypoglycemic effects of RG can be enforced by Bifidus fermentation and FRG may improve hyperlipidemia and hyperglycemia.

• Wind and Structures
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• v.20 no.2
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• pp.169-189
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• 2015

To investigate the effects of "sudden change" of wind fluctuations on vehicle running performance, which is caused by the artificial discrete simulation of wind field, a three-dimensional vehicle model is set up with multi-body dynamics theory and the vehicle dynamic responses in crosswind conditions are obtained in time domain. Based on Hilbert Huang Transform, the effects of simulation separations on time-frequency characteristics of wind field are discussed. In addition, the probability density distribution of "sudden change" of wind fluctuations is displayed, addressing the effects of simulation separation, mean wind speed and vehicle speed on the "sudden change" of wind fluctuations. The "sudden change" of vehicle dynamic responses, which is due to the discontinuity of wind fluctuations on moving vehicle, is also analyzed. With Principal Component Analysis, the comprehensive evaluation of vehicle running performance in crosswind conditions at different simulation separations of wind field is investigated. The results demonstrate that the artificial discrete simulation of wind field often causes "sudden change" in the wind fluctuations and the corresponding vehicle dynamic responses are noticeably affected. It provides a theoretical foundation for the choice of a suitable simulation separation of wind field in engineering application.