• The Korean Journal of Financial Management
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• v.25 no.4
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• pp.53-78
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• 2008

Foreign investors who invest in the Korean stock markets are exposed to two kinds of foreign exchange rate risk, the economic exposure and the translation exposure. The former is the foreign exchange rate exposure in return generating process of the assets invested and the latter is the foreign exchange rate exposure in the translation of domestic return into foreign investors' currency. Domestic investors, however, are exposed only to foreign exchange rate exposure in the asset invested. This different situation on foreign exchange rate exposure between foreign investors and domestic investors can induce different response to exchange rate change by investor groups. Previous studies on foreign exchange rate exposure of Korean firms reported that quite a few Korean firms are exposed to foreign exchange risks and suggested to manage the foreign exchange risks. Also, many studies on the market segmentation showed that a market can be practically segmented according to the characteristics of investor groups. These studies support the hypothesis that the Korean stock market can be practically segmented by the foreign investors' attitude to the foreign exchange rate exposure. This study examines the response of both foreign investors and domestic investors to the foreign exchange rate exposures in Korean stock markets. Test results show that foreign investors increase their sell transactions when the foreign exchange rate exposure of the previous day is negative. This result can be possible when foreign investors attempt to actively manage the decrease in value of their assets due to rising of exchange rate. Analysis on the sell order data is also supportive to this interpretation. Foreign investors also increase their buy transactions when the foreign exchange rate exposure of the previous day is negative. This result can be possible when foreign investors use actively the relation between the increase in asset value and the translation gain due to declining of exchange rate. Analyses on buy order data, however, do not show the same result as the analyses on transaction data. This difference may come from the difference of information contained in transaction data and order data. In summary, the result of the paper supports the hypothesis that foreign investors response differently to foreign exchange rate exposure compared with domestic, Korean investors. Two groups do not show different response when exchange rate exposure is positive, i.e., as foreign exchange rate is increase (decrease), the asset value is increase (decrease). However, foreign investors' response is different from that of domestic investors when exchange rate exposure is negative, i.e., as foreign exchange rate is increase (decrease), the asset value is decrease (increase). These results mean that foreign investors and domestic investors are placed in different situations related to foreign exchange rate exposure, and these differences are reflected in the Korean stock markets. And domestic investors need to consider foreign investors' different attitude to the foreign exchange rate exposure when they analysis foreign investors' trading behavior.

• Journal of Technologic Dentistry
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• v.19 no.1
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• pp.21-35
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• 1997

The Ag-Pd-Cu alloys containing a small amount of Au is commonly used for dental purposes, because this alloy is cheaper than Au-base alloys for clinical use. However, the most important characteristic of this alloy is age-hardenability, which is not exhibited by other Ag-base dental alloys. The specimens used were Ag-20Pd-20Cu ternary alloy and Au addition alloy. These alloys were melted and casted by induction electic furace and centrifugal casting machine in Ar atmoshpere. These specimens were solution treated for 2hr at $800^{\circ}C$ and were then quenched into iced water, and aged at $350{\sim}550^{\circ}C$ Age-hardening characteristics of the small Au-containing Ag-pPd-Cu dental alloys were investigated by means of hardness testing, X-ray diffraction and electron microscope observations, electrical resistance, differential scanning calorimetric, emergy dispersed spectra and electron probe microanalysis. Principal results are as follows : Hardening occured in two stages, I. e., stage I in low temperature and stage II in high temperature regions, during continuous aging. The case of hardening in stage I was due to the formation of the Llo type face centered tetragonal PdCu-ordered phase in the grain interior and hardening in stage I was affedted by the Cu concentration. In stage II, decomposition of the $\alpha$ solid solution to a PdCu ordered phase(L1o type) and an Agrich ${\alpha}2$ phase occurred and a discontiunous precipitation occurred at the grain boundary. Form the electron microscope study, it was concluded that the cause of age-hardening in this alloy is the precipitation of the PdCu ordered phase, which has AuCu I type face-centered tetragonal structure. Precipitation procedure was ${\alpha}\to{\alpha}+{\alpha}2+PdCu\to{\alpha}1+{\alpha}2+PdCu$ at Pd/Cu = 1 Ag-Pd-Cu alloy is more effective dental alloy as ageing treatment and is suitable to isothermal ageing at $450^{\circ}C$.

• The Journal of Korean Academy of Prosthodontics
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• v.47 no.4
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• pp.416-423
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• 2009

Statement of problem: The degree of light attenuation at the time of cementation of the PLV restoration depends on characteristics such as thickness, opacity and shade of the restorations, which interfere with light transmittance and, as a result, may decrease the total energy reaching the luting cement. Purpose: The purpose of this study was to compare the degree of conversion of light-cured resin cements measuring by FT-IR in regard to different thickness, light devices and curing time. Material and methods: In the control group, a clear slide glass (1.0 mm) was positioned between the light cured resin cement and light source. The specimens of ceramics were made with IPS Empress Esthetic. The ceramics were fabricated with varying thicknesses-0.5, 1.0, 1.5 mm with shade ETC1. Rely $X^{TM}$ Veneer with shade A3, light-cured resin cement, was used. Light-activation was conducted through the ceramic using a quartz tungsten halogen curing unit, a light emitting diode curing unit and a plasma arc curing unit. The degree of conversion of the light-cured resin cement was evaluated using FT-IR and OMNIC. One-way ANOVA and Tukey HSD test were used for statistical analysis ($\alpha$< .05). Results: The degree of conversion (DC) of photopolymerization using QTH and LED was higher than results of using PAC in the control group. After polymerization using QTH and LED, the DC results from the different ceramic thickness- 0.5 mm, 1.0 mm, 1.5 mm- did not show a significant difference when compared with those of control group. However, the DC for polymerization using PAC in the 1.5mm ceramic group showed significantly lower DC than those of the control group and 0.5 mm ceramic group (P<.05). At 80s and 160s, the DC of light-cured resin cement beneath 1.0 mm ceramic using LED was significantly higher than at 20s (P<.05). Conclusion: Within the limitation of this study, when adhering PLV to porcelain with a thickness between 0.5-1.5 mm, the use of PAC curing units were not considered however, light cured resin cements were effective when cured for over 40 seconds with QTH or LED curing units. Also, when curing the light cured resin cements with LED, the degree of polymerization was not proportional with the curing time. Curing exceeding a certain curing time, did not significantly affect the degree of polymerization.

• Tuberculosis and Respiratory Diseases
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• v.41 no.6
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• pp.624-631
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• 1994

Background: Genus of Aspergilli are ubiquitous saprophytic molds in nature, but its change from a saprophytic fungus to a pathogenic organism has occurred since the use of various antibiotics. The fungus affects the chronically ill and debilitated population. Recently frequency of the fungal infection is increasing in Korea with abuse of antibiotics and glucocorticoids. Method: We analyzed medical records of 52 patients with pulmonary aspergillosis seen at Hanyang University Hospital from 1980 to 1994. The results were as follows; Results: 1) Ages ranged between second to eighth decades with majority(50%) in the fourth to fifth decades. The male to female ratio was 1.1:1. 2) Hemoptysis and productive cough, the leading symptoms, occurred in 42.3% and 25% respectively. 3) On chest X-ray fingings, the characteristic "fungus ball" pattern were observed in 53.8% of the 52cases. 4) Sputum culture for aspergilli were positive in 21.6% of the cases. We performed fine needle aspiration in 22 patients and the diagnostic yield was 100%. 5) Thirty-six patients had history of treatment with antituberculous drugs under diagnosis of pulmonary tuberculosis for an average of 27.3 months. But sputum analysis for acid-fast bacilli were positive in 5.6%(2cases of 36cases), and postoperative pathologic findings showed that 38.9%(12 cases of 28cases) were combined with tuberculosis. 6) Right upper and left upper lobes were predominantly involved(34.6% and 19.2% respectively) and lobectomies were performed in 21 cases. 7) Underlying diseases were present in 47 cases and 48.9% of them were pulmonary tuberculosis. Conclusion: These results showed that pulmonary aspergillosis usually develops in patients with open cavitary pulmonary tuberculosis. And we must consider the possibility of pulmonary aspergillosis in a patient with hemoptysis and cavitary lung lesion.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.7
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• pp.1082-1090
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• 2005

Jocheong was prepared by adding Lentinus edodes extract to improve its quality and to give some functional properties. Contents of crude protein, ash and crude lipid were similar to those of control, while carbohydrate content was decreased. Total mineral content were $1,916.03\~2,674.24mg/kg$ that was no difference between test samples. From HPLC determination of free sugars, Jocheong was found to contain maltose as the highest sugar, followed by glucose and fructose. In amino acid analysis, seventeen amino acid were identified and quantified. Glutamic acid in Jocheong was major amino acid. The major fatty acids in Jocheong $(0\%,\;control)$ were linoleic acid, palmitic acid, oleic acid, myristic acid and caproic acid. There was no significant differences in fatty acid composition, pH and reducing sugar content among the Jocheong samples. The viscosity and solid contents tended to decrease with the addition of Lentinus edodes extract. Increasing the ratio of mushroom extract in Jocheong tended to decrease the lightness, yellowness and redness in Hunter's color value. Although sensory value decreased with increasing Lentinus edodes extracts, use of mushroom extracts (7: 3; saccharification liquids: Lentinus edodes extracts) is recommended for making Jocheong.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.2
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• pp.223-230
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• 2008

For the use of extracts from salmon frame as a basic material of Gomtang-like products, various methods (soaking into soybean milk, adding anchovy, and adding spices) for masking fish odor into extracts from salmon frame were examined and the food component characteristics were also compared with commercial Gomtang. According to the results of volatile basic nitrogen, transmission at 660 nm and sensory evaluation of extracts, soaking treatment, which is the soaking of salmon frame into soybean milk, was the most efficient method among the various methods for masking fish odor into extracts from salmon frame. There was no difference in the proximate composition between extracts from salmon frame soaked (FS) and unsoaked (C) into soybean milk. The FS was not detected in heavy metals, such as chromium, lead and cadmium. The taste value of FS (16.26) was higher than that of C and the major amino acids were glutamic acid and aspartic acid. Total amino acid content of FS (3.08 g/100 mL) was also higher than those of C (2.95 g/100 mL) and commercial Gomtang (1.70 g/100 mL), and the major amino acids were glycine, proline, glutamic acid and arginine. The calcium and phosphorus contents of FS/500 mL accounted for 21.7% and 18.5%, respectively, of the recommended daily allowance of mineral for adult.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.3
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• pp.348-356
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• 2008

For the effective use of rainbow trout, the seasoned and dried rainbow trout slice (SR) was prepared and its characterization was compared with the commercial skipjack tuna (CSS) and pork products (CSP) by determining chemical components and sensory evaluation. The moisture content of SR, 20.5%, was lower, and the lipid content of SR, 7.5%, was higher than those of commercial products, CSS and CSP. The protein content of SR (41.4%) was higher than that of CSS (28.6%), but lower than that of CSP (50.1%). The water activity of SR was 0.654, which was lower than those of CSS and CSP, 0.724 and 0.771, respectively. According to the results, the color of SR was lower in lightness and redness and higher in browning index and ${\Delta}$E value than that of commercial products. The texture of SR was harder than that of CSS, but softer than that of CSP. According to the result of taste value, the taste of SR was stronger than that of CSP, while weaker than that of CSS. The mineral (Ca, P, and Fe), total amino acid contents, and the n-3/n-6 of SR showed significant levels in nutrition and health functional senses.

• Journal of the East Asian Society of Dietary Life
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• v.26 no.5
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• pp.435-444
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• 2016

This study was conducted to investigate the effects of natural preservatives (G3, G3-1, F3, and F3-1) using Cordyceps militaris on improvement of food quality and safety of noodle during storage. Wheat flour noodle were prepared using three different concentrations of natural preservatives (0.100, 0.200, and 0.400%). Changes in microbial populations, pH value, titratable acidity, and sensory evaluation were measured during storage at $12{\pm}2^{\circ}C$ for 3 days. Overall, use of natural preservatives resulted in lower levels of total mesophilic bacteria, coliform, yeast and mold in noodle compared to the control. In particular, natural preservatives using $2{\times}$ MIC concentrations (0.400%) of F3 and F3-1 were effective at maintaining levels of total mesophilic bacteria for noodle during storage. The pH values of noodle made with F3 and F3-1 were higher than the others. The titratable acidity of noodle with natural preservatives did not significantly change during storage. In sensory evaluation, appearance, color, and overall acceptability of noodle with F3 and F3-1 were preferred than the control. These results could provide useful information for developing an alternative preservation method to improve food quality and shelf-life of noodle using natural preservatives.

• Korean Journal of Environment and Ecology
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• v.31 no.2
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• pp.230-251
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• 2017

According to the survey on higher fungi from 2009 to 2011 and also in 2015 in Byeonsanbando National Park, a total of 2 division, 6 class, 18 orders, 61 families, 157 genera and 323 species were observed. In case of Agaricales, there were 23 families, 67 genera and 153 species; Boletales, there were 6 families, 27 genera and 45 species; Russulales, there were 3 family, 4 genera and 40 species; Polyporales, there were 6 family, 21 genera, 28 species. Thus, most of them belonged to the following 4 orders: Agaricales, Russulales, Boletales and Polyporales. Dominant species belonged to Boletaceae (37 species), Russulaceae (36 species), Agaricaceae (28 species) and Amamtaceae (25 species). For the habitat environment, the ectomycorrhizal mushrooms were 40.2% (poisonous mushrooms, 46 species; edible & medicinal mushrooms, 51 species; unknown edible & poisonous mushrooms, 26 species), litter decomposing and wood rotting fungi 35.3%(poisonous mushrooms, 10 species; edible & medicinal mushrooms, 52 species; unknown edible & poisonous mushrooms, 46species), grounding Fungi 22.3%(poisonous mushrooms, 8 species; edible & medicinal mushrooms, 31 species; unknown edible & poisonous mushrooms, 29 species). Monthly, most of poisonous mushrooms, edible & medicinal mushrooms and unknown edible & poisonous mushrooms were found in July and August. In terms of altitude, the most species were observed at 1~99m and the populations dropped by a significant level at an altitude of 200m or higher. It seemed that the most diversified poisonous mushrooms, edible & medicinal mushrooms and unknown edible & poisonous mushrooms occurred at climate conditions with a mean air temperature at $24.0{\sim}25.9^{\circ}C$, the highest air temperature at $28.0{\sim}29.9^{\circ}C$, the lowest air temperature at $20.0{\sim}21.9^{\circ}C$, a relative humidity at 77.0~79.9% and a rainfall of 300.0~499.9mm.

• Journal of Bio-Environment Control
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• v.29 no.2
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• pp.130-140
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• 2020

This study was conducted in order to closely examine about optimum shading for superior seedling production a container seedling of Tetradium daniellii, which is being increased the demand for a seedling due to being used for alternative energy, ecological restoration and honey plant. The experiment of investigating the optimum shading on T. daniellii was carried out by using plastic container types (350 ml/cavity) for the forestry facility cultivation. The shading level was treated with full sunlight and with 35%, 55%, 75% of the full sunlight. As a result of having surveyed height and root collar diameter growth of a containerized seedling in T. daniellii, a case of the shading experiment showed a noticeably high value was indicated in the full sunlight. It was surveyed that the stronger shading level leads to the lower growth value. Root development was most active in full sunlight. Dry matter production, it was investigated to be the highest in full sunlight. It was surveyed to be the similar tendency to the outcome of height and root collar diameter growth. QI, which is index of showing the quality of a seedling, stood at 0.98 in full sunlight, thereby having been investigated to be the highest. As for the chlorophyll content in a seedling, the highest chlorophyll content was indicated in the 75% shading treatment with the relatively highest shading level. The photosynthetic rate and the water use efficiency were surveyed to be the highest in full sunlight with 8.48 μmolCO₂·m^-2s^-1, 1.40 μmolCO₂·mmolm^-1H₂O, respectively. As a result of surveying the whole experiment, optimum shading level for superior seedling production a container seedling of T. daniellii is determined in full sunlight (0%). It is expected that this will be used as a basic data for mass production.