• Korean Journal of Child Studies
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• v.24 no.6
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• pp.33-46
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• 2003

This study investigated age differences in children's expression of pride and shame by their age, and type and level of task difficulty when they succeeded of failed on tasks. The subjects were 55 4-year-old children from 2 day-care centers and 37 7-year-old children from I elementary school. Each child participated in pride and shame assessment sessions. Data were analyzed by repeated measures ANOVA, t-test, paired t-test, Pearson's correlations. When they succeeded on tasks, 4-year-olds showed more pride than 7-year-olds. More pride was shown when subjects succeeded on difficult than on easy tasks. An interaction effect for pride was found between age, and type and level of task difficulty. Seven-year-olds showed more shame than 4-year-olds when they failed on tasks. More shame was shown when subjects failed on easy than on difficult tasks. The expression of pride was positively related to the expression of shame.

• International Journal of Advanced Culture Technology
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• v.12 no.1
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• pp.202-208
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• 2024

Objective: The purpose of this study is to examine the competitive environment of 7-Eleven using Porter's 5 Force model to analyze the specific competitiveness of 7-Eleven that has maintained continuous growth as a competitive company. Methods: This study is a case study of 7-Eleven. Results: As a result of the analysis, 7-Eleven has reinforced its competitiveness with existing competitors by raising entry barriers by expanding domestic stores and developing overseas convenience store business, focusing on North America, based on economy of scale. In addition, 7-Eleven seeks to differentiate itself from other convenience stores by developing a "private brand" and strengthens its bargaining power with suppliers through the development of new products by gathering information and know-how of experts in product development based on customer needs. The bargaining power with customers has been strengthened by building loyalty and trust in the brand by allowing consumers to purchase the same products at the same price no matter which store they visit. As a threat to potential competitors, 7-Eleven has secured a competition advantage by raising the barrier to entry by concentrating stores in specific areas through a dominant franchise development strategy and increasing awareness of 7-Eleven among consumers. In the case of threats from substitute products, it was confirmed that 7-Eleven has overcome the threat from substitute products by opening 24 hours a day and providing various services such as ATMs and copiers.

• The Journal of Korean Academic Society of Nursing Education
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• v.24 no.3
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• pp.269-278
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• 2018

Purpose: This study was conducted to investigate the correlation between stress and adjustment to college life among nursing students. Methods: The sample consisted of 183 university students in C & S cities. Self-report questionnaires were used to measure the variables. In data analysis, SPSSWIN 23.0 program was utilized for descriptive statistics, Pearson's correlation coefficients, and regression analysis. Results: The mean scores of stress and adjustment to college life were 2.55 and 3.24. Stress was significantly different according to grade (F=7.30, p<.001), economic state (F=14.39, p<.001), perceived health state (F=6.66, p<.001). In regression analysis, stress for college life, perceived health state, and college life satisfaction were significant predictors of adjustment to college life explaining 68%. Conclusion: This study suggests that perceived health state was a significant factor on adjustment to college life among nursing students. Therefore, the strategies of nursing intervention which improve perceived health state must be developed for college students.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.11
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• pp.1385-1390
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• 2007

Anticarcinogenic-active compound was isolated and purified from Angelica gigas Nakai. The compound was identified as decursin ($C_{19}H_{20}O_5$; molecular weight 328) by mass, IR spectrophotometry $^1H-NMR$ and $^{13}C-NMR$. The proliferation decreased in a dose dependant fashion in the MCF-7 cells treated with decursin for 24 hours over the concentration of $20{\mu}g/mL$. The $IC_{50}$ value of the decursin treatment for 24 hours were 31.04, 33.60, 27,24, $20.45{\mu}g/mL$ in the SW480, 293, HepG2 and MCF-7 cells, respectively, The growth inhibitory effect was stronger in the MCF-7 cells compared to other cells including 293 of human normal cells. The chromatin condensation, apoptotic body formation and DNA fragmentation were examined in the cells treated with decursin. These results suggest that decursin from Angelica gigas Nakai inhibited the growth through apoptosis in MCF-7 cells.

• Journal of Life Science
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• v.24 no.8
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• pp.903-909
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• 2014

Plants are an invaluable source of potential new anti-cancer drugs. Sasa quelpaertensis Nakai (Korean name, Jeju-Joritdae) is one of these plants with medical value, which is a bamboo grass widely distributed in Mt. Halla on Jeju Island, Korea. Here, we investigated the apoptotic effects of S. quelpaertensis leaf extracts in six human cancer cell lines (A549, MCF-7, HepG-2, Hela, HCT116 and A375). MTT assay signified the antiproliferative nature of S. quelpaertensis extracts against all tested cancer cells: S. quelpaertensis displayed slight cytotoxicity against A549, MCF-7 and HepG-2 cells, whereas it was exclusively cytotoxic to Hela, HCT116 and A375 cells. Apoptotic cells were evaluated using PI staining of DNA fragmentation by flow cytometry (sub-G1 peak). PI staining indicated increasing accumulation of Hela, HCT116 and A375 cells at sub-G1 phase. Further events like generation of nitric oxide ($NO^{\bullet}$) were accompanied in the S. quelpaertensis Nakai-induced apoptosis. Augmented $NO^{\bullet}$ generation resulted in the DNA fragmentation of Hela, HCT116 and A375 cells by treatment with S. quelpaertensis leaf extracts. These results suggest that S. quelpaertensis may be a potential natural resource for treating cancer cell. To identify the exact mechanisms of molecular mechanism of S. quelpaertensis induced apoptosis awaits further investigation.

• Journal of Wetlands Research
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• v.3 no.2
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• pp.143-151
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• 2001

The community of phytoplankton, dominant species and environmental factor were investigated in Motjae-neup from January to September, 1996. A total 45 taxa were identified during the investigation period and composed of 5 classes, 8 orders, 13 families, 24 genera, 37 species, 6 varieties, 2 formation. The most important group was Chlorophyceae with 19(42.2%) taxa, followed by the Bacillariophyceae with 13(28.9%) taxa, Euglenophyceae with 7(15.6%) taxa, Cyanophyceae with 5(11.1%) taxa and Dinophyceae with 1(2.2%) taxon. Frustulia rhomboides, Eunotia lunaris, and Stauroneis anceps were important dominant species at Motjae-neup. The common species of all season are Microsystis aeruginosa, Melosira. varians, Frustulia rhomboides, Pinnularia braunii var. amphicephala, Stauroneis anceps. Ranges of environmental factors were measured : temperature, $3^{\circ}C{\sim}38^{\circ}C$; water temperature, $3.3^{\circ}C{\sim}26.5^{\circ}C$; pH, 5.7~6.38; BOD, $4.3{\sim}19.6mg/{\ell}$; chlorophyll a, $6.9mg/m^3{\sim}25.9mg/m^3$; SS, $26mg/{\ell}{\sim}52mg/{\ell}$; COD, $24{\sim}46mg/{\ell}$; total-N, $0.9538mg/{\ell}{\sim}2.3036mg/{\ell}$; total-P, $0.1057mg/{\ell}{\sim}0.1909mg/{\ell}$; electron conductivity, $25.5{\mu}s/m^3{\sim}2.3036{\mu}s/m^3$.

• Korean Journal of Food Science and Technology
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• v.21 no.1
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• pp.120-126
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• 1989

Streptococcus diacetylactis and Leuconostoc cremoris were isolated from commercial culture and the effects of culture conditions on the diacetyl production by these strains and their mixture(1:1) were investigated. Optimum temperatures and culture times for the diacetyl production by Str. diacetylactis, Leu, cremoris and their mixture were 60hr at $22^{\circ}C$(diacetyl content, 2.24ppm), 48hr at $22^{\circ}C$(2.29ppm) and 48hr at $22^{\circ}C$ (2.21ppm), respectively Optimum initial pH for the diacetyl production by Str. diacetylactis, Leu. cremoris and the mixture were all 4.8(4.32, 6.66, 7.30ppm, respectively) and optimum sodium citrate concentrations(%, w/v) were 0.30(2.58ppm), 0.1(2.54ppm) and 0.1(2.52ppm), respectively. The diacetyl contents were gradually increased according as inoculation rates(%, w/v) were increased. The amounts of diacetyl produced under optimum conditions at 24hr incubation by Str. diacetylactis, Leu. cremoris and the mixture were 4.40, 6.59 and 7.25ppm, respectively. The most effective factor affecting diacetyl production under optimum condition was pH.

• Korean Journal of Food Science and Technology
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• v.27 no.5
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• pp.742-747
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• 1995

The effect of storage temperature and period on the contents of tin, iron, lead and vitamin C, browning index and pH was studied for canned and bottled orange juices currently sold in Korean market, which were stored for 24 weeks at 20, 30, 40 and $50^{\circ}C$ and analyzed at 4 week intervals. The change of metal content in bottled juices was negligible but metal release in canned juices was remarkably affected by storage temperature. Tin content after 16 weeks increased by $2.7{\sim}13.1$ times, iron content after 24 weeks increased by $4.3{\sim}5.2$ times and lead content after 24 weeks increased by $1.1{\sim}2.9$ times. Retention of total ascorbic acid in canned juices after 24 weeks at $30{\sim}50^{\circ}$ decreased to $13{\sim}76%$, while that in bottled juices decreased to $4{\sim}80%$. Browning index in canned juices after 24 weeks below $40^{\circ}C$ increased slightly with serious discoloration at $50^{\circ}C$ while that in bottled juices increased a little rapid. pH change in canned and bottled juices during storage below $40^{\circ}C$ was not observed regardless of container type but a great change of pH was accompanied with swelling of container ends in the case of canned juices after 24 weeks at $50^{\circ}C$.

• Proceedings of the IEEK Conference
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• 2002.07b
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• pp.880-883
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• 2002

We propose an effective wavelength converter method using frequency shifter for photonic node, and examine the scalability of Generalized Multiprotocol Label Switching (GMPLS) networks. The ana1ysis is examined based on signal to noise ratio (SNR) for present 2.4 and 10 Gbit/s Synchronous Digital Hierarchy (SDH) networks, and next generation 2.7 and 10.8 Gbit/s Optical Transport Networks (OTN) format The proposed 100 channels GMPLS networks using optical frequency shifters are shown to be applicable to transmission network spanning over 1206 km(24 nodes) in 2.7 Gbit/s trunk networks. Transmission over more than 310 km (6 nodes) is also possible in 2.7 Gbit/s Metroporitan Area Networks(MAN).

• Korean Journal of Food Science and Technology
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• v.3 no.1
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• pp.57-63
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• 1971

1) Among five lactic acid bacteria examined, Str. thermophilus and Str. diacetilactis produced remarkably greater amount of acids in soybean milk than Str. lactis, Str. cremoris and L. bulgaricus. 2) Soybean milk and skimmed dry milk were combined in the ratio of 7 : 3 and were carried out in lactic acid fermentation for 24 hours at optimum temperature. The result indicated that the yield of precipitation and protein content of it were the most, the moisture content was the least and curd structure formed was considered too hard. 3) Based on these and other results, following procedure was used for manufacturing: soybean milk and skimmed dry milk were combined in the ratio of 7 : 3, heated at $121^{\circ}C$ for 20 min., cooled, added Str. thermophilus as lactic acid starter and incubated for 24 hours and $37{\pm}1^{\circ}C$. The curd was cooked, hooped, and pressed for 24 hours, to the surface of which, Penicillium caseicolum and sodium chloride were spread. During ripening of the curd at $15^{\circ}C$ and $85{\sim}90%$ RH for 21 days, Pen. caseicolum was highly developed after 7 days, pH was increased and proteolytie activity has reached to the peak point after 14 days. After 7 days of ripening total water soluble nitrogen, water soluble protein nitrogen and amino acids nitrogen were begun to increase. After 21 days of ripening total water soluble nitrogen, water soluble protein nitrogen and amino-N reached to 52%, 32% and 14% of total nitogen. In the soybean cheese, after 21 days of ripening, 17 or more kinds of amino acids were detected by two-dimentional paper chromatography. The product contained 63.2% of moisture, 17.5% of crude protein, 13.2% of crude fat, 2.8% of crude ash and 2.5% of sodium chloride.