• Journal of Distribution Research
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• v.11 no.2
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• pp.29-57
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• 2006

While a number of studies have recognized the importance of environment of channel systems and consequences of changed environment, only limited studies have dealt with this issue theoretically and practically. The purpose of this study is to empirically validate whether one dimension of environment, called dynamism, has an influence on the relationship characteristics such as transaction specific investment opportunism and conflict or not: further, it is designed to delve into whether these relationship characteristics have any influence on one crucial relationship quality, 'trust' and its two constituent dimensions - credibility and benevolence. In order to provide empirical validation, a survey was conducted to 163 sales office managers at a major newspaper publisher in Korea. An analysis of the data retrieved from this survey indicated that while environmental dynamism has a positive influence on the publisher's opportunism and conflict perceived by the sales office managers, it did not show a direct influence on the transaction specific investment made by the publisher. Furthermore, while publisher's transaction specific investment had a positive influence on the credibility and the benevolence respectively, publisher's opportunism and level of sales office conflict had a negative influence on the credibility and the benevolence respectively. Currently, a publisher is facing an unprecedentedly dynamic environment. This study should provide ample implications for the publisher in establishing trust, which is a crucial condition in developing and maintaining a long-term successful relationship with its sales offices.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.2
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• pp.166-176
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• 2009

Eighteen Korean chestnut cultivars were collected from various places and the proximate compositions, dietary fiber, amino acid and free sugar contents in three parts (whole kernel, white kernel, yellow kernel) of eighteen Korean chestnut cultivars were analyzed. The white kernel of Chukfa and the yellow kernel of Ipyung contained the highest amount of moisture and crude protein, respectively. Carbohydrate content of whole kernel showed a range of $30.8{\sim}52.0%$ and crude ash content of whole kernel showed a range of $0.9{\sim}1.8%$. The amount of crude lipid was the highest in Byunggo. The amount of dietary fiber in Kwangeun, Daebo, Parkmi 1 ho, Yooma and Pyeonggi were higher than that of other Korean chestnut cultivars. Seventeen amino acids were detected. Major amino acids of the various chestnuts were aspartic acid and leucine. The amount of amino acids was higher in Ichui, Ipyung and Pyeonggi but was lower in Dantaek and Sandae than that of other samples. The major free sugar in the chestnuts was glucose. The free sugar amount of yellow kernels was higher than the white kernels.

• Composites Research
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• v.12 no.3
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• pp.75-83
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• 1999

The thermal properties of carbon/phenolic and silica/phenolic ablative composites were investigated by measuring the heat capacity, thermal diffusivity and thermal conductivity. The heat capacities of carbon/ phenolic and silica/phenolic composites were calculated from differential scanning calorimeter curve. The thermal diffusivities of carbon/phenolic and silica/phenolic composites were measured by the laser flash method with varying laminated direction, i.e., with laminar direction and across laminar direction. The thermal diffusivities decreased with increasing temperature. The thermal conductivities of carbon/phenolic and silica/phenolic composites were calculated using the heat capacity, density and thermal diffusivity. The thermal conductivities increased with increasing temperature. The thermal conductivity of with laminar direction is two times higher than that of across-laminar direction in carbon/phenolic composite due to the directionality of thermal conductivity of carbon fiber. The thermal conductivities of two dimensional fiber reinforced composites were analyzed using the conductivities of constituents and volume fraction of each constituent. The thermal conductivities of carbon fiber and silica fiber were calculated from thermal conductivities of carbon/phenolic and silica/phenolic composites. The thermal conductivities of carbon/phenolic and silica/phenolic composites at RT were predicted from thermal conductivities of fiber and resin with varying the volume fraction of fiber.

• Journal of Korean Society for Atmospheric Environment
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• v.24 no.6
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• pp.682-692
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• 2008

Fine particles ($PM_{2.5}$) were collected and analyzed from November 2005 through August 2007 in Chuncheon, Korea to investigate the characteristics of $PM_{2.5}$ and its ionic constituents. The average $PM_{2.5}$ concentration during the study period was $39{\mu}g/m^3$, which is almost two times higher than the annual US NAAQS $PM_{2.5}$ standard of $15{\mu}g/m^3$. $PM_{2.5}$ concentrations were higher in spring and winter than in summer and fall. During spring, Asian Dust events dramatically enhanced $PM_{2.5}$ concentrations, and long-range transport of $PM_{2.5}$ emitted in industrial area of China often occurred during winter based on trajectory analysis. Contribution of $PM_{2.5}$ to $PM_{10}$ concentrations ranged from $72{\mu}g/m^3$ during Asian Dust events to $457{\mu}g/m^3$, indicating that a large portion of $PM_{2.5{\sim}10}$ was transported from China during Asian Dust events. Among the major ionic constituents ${SO_4}^{2-}$ showed the highest concentration, followed by ${NH_4}^+$, ${NO_3}^-$ and ${NO_2}^-$. Chuncheon appeared to be ${NH_4}^+$ rich environment, indicating that $(NH_4)_{2}SO_4$ and ${NH_4}{NO_3}$ were the predominant forms of ${NO_3}^-$ and ${SO_4}^2$ in $PM_{2.5}$. Haze has frequently occurred in Chuncheon since So-Yang dam was constructed in 1973. Haze events were observed on 23 days during sampling period, and the average $PM_{2.5}$ concentration was approximately 1.6 times higher during haze events than during non-haze events. This result suggests that haze enhances the secondary aerosol formation because the aerosol spontaneously absorbs water to form a saturated salt solution, deriving a significant increase in the mass of the particle.

• Journal of Conservation Science
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• v.33 no.6
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• pp.485-495
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• 2017

The purpose of this study is to evaluate the functionality and lightfastness of the natural pigments according to the type of Seokganju used as Dancheong. The commercially available red iron-oxide-based natural pigments that are called Seokganju and Daija manufactured by traditional methods in Korea and Japan were selected. The analysis of the constituent minerals and constituents of 8 kinds of collected Seokganju showed that most of them contained hematite. There are two types of Seokganju according to the $Fe_2O_3$ contents. The type of Seokganju can be characterized not only using the main component but also from the burn-out processing. The chromaticity results for Seokganju with a high $Fe_2O_3$ concentration indicate dark red or grayish brown, while those for Seokganju with a low $Fe_2O_3$ concentration indicate yellowish red or yellowish brown. Samples were prepared by mixing with a glue solution and functional properties were evaluated based on the opacity and spreadability. Coated samples were used in the lightfastness test. The spreadability and opacity of the pigments were measured differently depending on the main component. Most Seokganju samples a showed slight color change until $9,000kJ/m^2$ but rapid color changes were detected after $18,000kJ/m^2$. In particular, burnt Seokganju showed superior lightfastness.

• The Journal of Korean Medicine
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• v.29 no.2
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• pp.182-192
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• 2008

Objective: The purpose of this study was to evaluate on the antimicrobial effect on the periodontal pathogens and anti-inflammatory effect of Eriobotryae folium. Eriobotryae folium are constituent herbs of Gagamgamroum, which has been used for a long time in oriental medicine as a herbal medicine for treating halitosis and toothache. Method: Eriobotryae folium was prepared by extracting medicinal herb with water. We investigated antimicrobial activity by the minimum inhibitory concentration (MIC) test. We also investigated inhibition of $IL-1{\beta}-induced$ collagenase (mmp-1), stromelysin-1 (mmp-3), interleukin-6 gene expression in human gingival fibroblasts using RTPCR analysis. Result: The antimicrobial effects of Eriobotryae folium was evaluated with MIC against periodontopathogens; Porphyromonas gingivalis 2561, W50, A7A1-28, 9-14K-1, Prevotella intermedia 28, and Actinobacillus actinomycetemcomitans Y4. MICs of Eriobotryae folium were 1.25 mg/ml, 2.5 mg/ml, 0.625 mg/ml, 1.25 mg/ml, 10 mg/ml and 10 mg/ml. The anti-inflammatory effect of Eriobotryae folium was evaluated with influence of herbs on the $IL-1{\beta}-induced$ expression of mmp-1, mmp-3, and interleukin-6. $IL-1{\beta}$ increased mmp-1, mmp-3, and interleukin-6 mRNA levels. Eriobotryae folium significantly inhibited $IL-1{\beta}-induced$ mmp-1, mmp-3, and interleukin-6 gene expressions in a dose-dependent manner. Conclusion: These results suggested that Eriobotryae folium might reduce the excessive proteolytic capacity of the gingival fibroblast during inflammation and could be developed as a new drug for periodontitis.

• The Korean Journal of Physiology and Pharmacology
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• v.21 no.3
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• pp.309-316
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• 2017

Transient receptor potential vanilloid 3 (TRPV3) is a non-selective cation channel with modest permeability to calcium ions. It is involved in intracellular calcium signaling and is therefore important in processes such as thermal sensation, skin barrier formation, and wound healing. TRPV3 was initially proposed as a warm temperature sensor. It is activated by synthetic small-molecule chemicals and plant-derived natural compounds such as camphor and eugenol. Schisandra chinensis (Turcz.) Baill (SC) has diverse pharmacological properties including antiallergic, anti-inflammatory, and wound healing activities. It is extensively used as an oriental herbal medicine for the treatment of various diseases. In this study, we investigated whether SC fruit extracts and seed oil, as well as four compounds isolated from the fruit can activate the TRPV3 channel. By performing whole-cell patch clamp recording in HEK293T cells overexpressing TRPV3, we found that the methanolic extract of SC fruit has an agonistic effect on the TRPV3 channel. Furthermore, electrophysiological analysis revealed that ${\gamma}$-schisandrin, one of the isolated compounds, activated TRPV3 at a concentration of $30{\mu}M$. In addition, ${\gamma}$-schisandrin (${\sim}100{\mu}M$) increased cytoplasmic $Ca^{2+}$ concentrations by approximately 20% in response to TRPV3 activation. This is the first report to indicate that SC extract and ${\gamma}$-schisandrin can modulate the TRPV3 channel. This report also suggests a mechanism by which ${\gamma}$-schisandrin acts as a therapeutic agent against TRPV3-related diseases.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.1
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• pp.566-576
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• 2018

As the weapon systems of the Korean Army possess massive firepower and multiple functions, the improvement of their quality through reliability prediction is becoming increasingly important. Currently, the reliability prediction of the weapon systems of the Korean Army is a difficult process, because it is conducted by naively calculating the reliability of their constituent parts. Recently, as various studies using accumulated data are undertaken across various industries, the defense industry is also attempting to analyze the Dark Data which have been accumulated but not yet used. Therefore, it is necessary to apply Post-Logistics Support (PLS) data in order to improve the reliability of the weapon systems and, for this purpose, the Korean Army needs to conduct diverse studies. Especially, the PLS data in the defense industry is very useful for reliability prediction, because the data on the defects reported after the development of the weapon systems are accumulated in this phase. This study examines the existing reliability prediction method conducted using the component parts and proposes a new reliability prediction method using PLS data. This framework can ultimately contribute to improve the prediction accuracy and quality of the weapon systems.

• Journal of the Korean Society of Marine Environment & Safety
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• v.23 no.5
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• pp.497-512
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• 2017

Temporal and spatial variations in surface water temperature were studied using data from temperature monitoring buoys deployed at 47 stations around Boryeong from 2011-2012 off the west coast of Korea. Temperature fluctuations are predominant at diurnal and semidiurnal periods for all seasons, and their amplitudes are large in spring and summer but small in autumn. The maximum annual change in air temperature takes place on August 2nd and August 22th for water temperature, which means the phase for air temperature precedes water temperature by 20 days. The diurnal period of water temperature fluctuation is predominant around Daecheon and Muchangpo Harbors, with the semidiurnal period around Wonsan Island, and the shallow water constituent period on the estuary around Daecheon River. On the whole, air and water temperatures fluctuate with wind. Spectral analyses of temperature records show significant peaks at the 0.5, 1 and 15 day marks with 7-10 day periods of predominant fluctuations. Cross-correlation analyses for the temperature fluctuation show that the waters around Boryeong can be classified into four areas: a mixed water zone around the southeast side of Wonsan Island, an off-shore area to the west, an off-shore area to the south and a coastal area along the shore from Song Island to Muchangpo Harbor.

• Nutrition Research and Practice
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• v.5 no.5
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• pp.396-403
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• 2011

Ceramides (Cer) comprise the major constituent of sphingolipids in the epidermis and are known to play diverse roles in the outermost layers of the skin including water retention and provision of a physical barrier. In addition, they can be hydrolyzed into free sphingoid bases such as $C_{18}$ sphingosine (SO) and $C_{18}$ sphinganine (SA) or can be further metabolized to $C_{18}$ So-1-phosphate (S1P) and $C_{18}$ Sa-1-phosphate (Sa1P) in keratinocytes. The significance of ceramide metabolites emerged from studies reporting altered levels of SO and SA in skin disorders and the role of S1P and Sa1P as signaling lipids. However, the overall metabolism of sphingoid bases and their phosphates during keratinocyte differentiation remains not fully understood. Therefore, in this study, we analyzed these Cer metabolites in the process of keratinocyte differentiation. Three distinct keratinocyte differentiation stages were prepared using 0.07 mM calcium (Ca$^{2+}$) (proliferation stage), 1.2 mM Ca$^{2+}$ (early differentiation stage) in serum-free medium, or serum-containing medium with vitamin C (50 ${\mu}L$/mL) (late differentiation stage). Serum-containing medium was also used to determine whether vitamin C increases the concentrations of sphingoid bases and their phosphates. The production of sphingoid bases and their phosphates after hydrolysis by alkaline phosphatase was determined using high-performance liquid chromatography. Compared to cells treated with 0.07 mM Ca$^{2+}$, levels of SO, SA, S1P, and SA1P were not altered after treatment with 1.2 mM Ca$^{2+}$. However, in keratinocytes cultured in serum-containing medium with vitamin C, levels of SO, SA, S1P, and SA1P were dramatically higher than those in 0.07- and l.2-mM Ca$^{2+}$-treated cells; however, compared to serum-containing medium alone, vitamin C did not significantly enhance their production. Taken together, we demonstrate that late differentiation induced by vitamin C and serum was accompanied by dramatic increases in the concentration of sphingoid bases and their phosphates, although vitamin C alone had no effect on their production.