• Journal of the Korean Society of Food Science and Nutrition
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• v.12 no.3
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• pp.297-304
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• 1983

The water content, respiration rate, solid, and starch contents in the potate tuber of May Queen and Namjak stored at $5^{\circ}C$ and $20^{\circ}C$ were determined during 27 week period. Changes in appearance of the surface and internal tissue also were observed. The dormancy period of May Queen stored at $5^{\circ}C$ and $20^{\circ}C$ was 12 seeks, but Namjak at $5^{\circ}C$ and $20^{\circ}C$ were 9 weeks and 21 weeks, respectively. Greening developed from 12 weeks in the tuber of May Queen at $5^{\circ}C$ and browning of Namjak stored at $5^{\circ}C$ was observed from 6 weeks. In both potatoes stored at $20^{\circ}C$, the rates of respiration were higher than those stored at $5^{\circ}C$, and the rates increased continuously after sprouting at $20^{\circ}C$ but maintained at the low level at $5^{\circ}C$. Solid and starch contents of Namjak were always higher than those of May Queen during 27 weeks, but the levels did not change significantly with time. Solid and starch contents at $20^{\circ}C$ maintained at higher level than at $5^{\circ}C$.

• Journal of the Korean Society of Food Science and Nutrition
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• v.14 no.2
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• pp.95-98
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• 1985

This study was carried out to investigate changes in the compositions of fatty acids according to the different drying methods of raw mugwort. Raw mugwort from Kang-wha was dried with four methods such as sun-drying, shady sun-drying, heated oven-drying and freeze-drying. Total contents and fatty acid compositions of the ethyl ether extracts from the dried mugworts were examined. Total contents of the ethyl ether extracts showed remarkable differences with drying methods; freeze-dried mugwort had the highest content (5.60%), while oven dried mugwort revealed the lowest content (2.45%). Eleven fatty acids and four unknown peaks were identified by gas-liquid chromatography; major fatty acids were linoleic acid, linolenic acid and palmitic acid. Fatty acids of mugworts dried by 4 different methods were the same in kinds, but different in their compositions. The content of polyunsaturated fatty acids $(C_{18:2}+C_{18:3})$ was the highest and the loss of low volatile fatty acids was the least in mugwort dried by the freeze-drying method. The volatile fatty acids considerably decreased in oven-dried mugwort. However, the contents of polyunsaturated fatty acids were a little higher in oven-dried mugwort than in sun-dried and shady sun-dried mugwort, and the lowest in sun-dried mugwort.

• Journal of Ginseng Research
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• v.23 no.4
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• pp.230-234
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• 1999

Potassium channels play an important role in regulating vascular smooth muscle tone. Four types of $K^+$ channels areknown to be expressed in vascular smooth muscle cells, and maxi $Ca^{2+}-activated\;K^+$ channel $(BK_{Ca})$ is a dominant type of $K^+$ channels in these cells. Because total ginseng saponins and ginsenoside $Rg_3$ cause vasodilation with unclear mechanisms, we hypothesized that total ginseng saponins and ginsenoside $Rg_3$ induce vasodilation via activation of maxi $Ca^{2+}-activated\;K+$ channels. Whole-cell BKe. currents were voltage-dependent with half maximum activation at -14 mV, and the currents were sensitive to nanomolar ChTX and millimolar TEA. External application of total ginseng saponins increased the anlplitude of the whole-cell BKe. current in a concentration-dependent manner. Single-channel analysis indicates that total ginseng saponins caused the channel opening for a longer period of time. Ginsenoside $Rg_3$ increased the amplitude of whole-cell $K_{Ca}$ currents without affecting voltage dependence of the currents and increased single-channel open time. Hence, the results suggest that ginseng saponin-induced vasodilation may be due to activation of $K_{Ca}$.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.41 no.3
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• pp.72-82
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• 2018

In this paper, we identify risk factors that are likely to occur during the lifecycle of a new product development (NPD) project from the literatures, and identify the three objectives or three constraints that will ultimately be achieved for project success in the ICT industry : performance (scope/quality), schedule (time), and cost. Firstly, we interviewed the project experts to classify the risk factors according that the final project objectives are changeable based on scope/quality, time and cost budget constraints. Secondly, the survey for pairwise comparisons between the risk factors was asked to the project managers and members who had ever actually participated in the NPD projects of ICT industry to determine the priority ranks on relative importance using AHP (Analytic Hierarchy Process). The risk factors negatively affecting the goals of projects were analyzed by using the AHP respectively in four project stages during the life cycle of the project. The comparison of risk factors within each stage is a different approach unlike the literatures which have covered project's overall risk assessment. There is an advantage that risk management can be effectively performed with priorities according to each stage from the start to the end of the project. In other words, it is necessary to identify what risk factors will occur in each stage, and to have ideas at each stage with the priorities so that they can be mitigated and eliminated before actual occurrence. As a result, risks on scope & quality changes were found to be the most important considerations for initiative stage of NPD projects in the ICT industry, whereas in the final stage, risks on schedule (time) changes were the most important priorities. Among the ICT industry product categories, 'communication and broadcasting devices' and 'IT and communication based devices' generally have a high priority in terms of risks on scope & quality changes when initiating the project. At the closing stage of the project, however, considering that schedule (time) changeable risk is getting higher, these products tend to target at B2B market rather than B2C because the new products must be delivered and launched in time as customer firm required.

• Journal of the Korean Society for Railway
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• v.19 no.5
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• pp.617-628
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• 2016

This paper proposes the structure of a smart transformer to improve the performance of the 60Hz main power transformer for rolling stock. The proposed smart transformer is a kind of solid state transformer that consists of semiconductor switching devices and high frequency transformers. This smart transformer would have smaller size than the conventional 60Hz main transformer for rolling stock, making it possible to operate AC electrified track efficiently by power factor control. The proposed structure employs a cascade H-Bridge converter to interface with the high voltage AC single phase grid as the rectifier part. Each H-Bridge converter in the rectifier part is connected by a Dual-Active-Bridge (DAB) converter to generate an isolated low voltage DC output source of the system. Because the AC voltage in the train system is a kind of medium voltage, the number of the modules would be several tens. To control the entire smart transformer, the inner DC voltage of the modules, the AC input current, and the output DC voltage must be controlled instantaneously. In this paper, a control algorithm to operate the proposed structure is suggested and confirmed through computer simulation.

• The Journal of the Convergence on Culture Technology
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• v.6 no.2
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• pp.231-238
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• 2020

The main purpose of this current study was to identify the structural relationships between the variables of team attachment, location-based service, and future fan behaviors by utilizing Technology Acceptance Model (TAM). Among the 10 KBO franchises, SK Wyverns and KT Wiz were qualified to have their own smart applications programs and the relevant infrastructure at their home venues. Thus, a total of 500 surveys were collected from SK Wyverns and KT Wiz games during September of 2019 and a total of 448 were used for data analysis after deleting 52 surveys due to the missing data. According to the results of a structural equation modeling, 12 positive (+) causality out of 14 hypotheses were confirmed that there must be causal relationships among the variables of location-based service at the smart stadium, TAM, fan attachment, and future fan behavior. It is hoped that this study can be contributing to the foundational developments of marketing strategies by adopting the new technological advancement in the Korean sport industry in the future.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.23 no.2
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• pp.69-75
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• 2012

Objectives : The current study was conducted in order to investigate teachers' recognition of school bullying using a nationwide database of adolescents in middle and high school in Korea. Methods : Students in the 7th to 12th grades at 23 secondary schools participated in the current study during the fall of 2009. Subjects completed the self-report form of the Adolescent Mental Health and Problem Behavior Screening Questionnaire-II (AMPQ-II) and Symptom Checklist-90 Revised (SCL-90-R). In addition, relevant teachers used the teachers' rating scale of the AMPQ-II to report their students' status. Differences in the number of bullied students between teachers' recognition and students' report were explored. Results : A total of 2270 subjects provided relevant responses to the questionnaire. While the one-month prevalence of victimization according to students' self-reports was 28.9%, the recognized prevalence by teachers was only 10.6%. For prediction of the presence of school bullying according to students' self reports on the AMPQ-II, item 7 of the teachers' report on the AMPQ-II showed a sensitivity of 16%, a specificity of 92%, a positive predictability of 44%, a negative predictability of 72%, a false positive rate of 8%, a false negative rate of 84%, and an accuracy of 69%, respectively. No significant differences in subscores of students' self reports of the AMPQ-II and SCL-90-R were observed between bullied students who were recognized by teachers and those who were not recognized. In stepwise discriminant analysis, classification of teachers' item 2 and item 7 on the AMPQ-II with respect to school bullying according to students' reports showed an accuracy of 63.4%. Using this model, 75.2% of non-victimized subjects were classified correctly, while only 35.2% of victimized subjects were classified correctly. Conclusion : Despite the high prevalence in Korea, teachers' recognition of school violence among their students remains low. Pre-professional and continuing education to improve teachers' understanding of school bullying and knowledge of effective classroom-based prevention activities should be encouraged.

• Journal of the East Asian Society of Dietary Life
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• v.20 no.6
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• pp.873-880
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• 2010

The purpose of this study was to investigate the quality characteristics of sponge cake with broccoli (Brassica oleracea var. italica Plenck) powder. Broccoli powder was mixed with wheat flour at various ratio (3, 5, 7, 9%, w/w) for physical and sensory evaluations. The specific gravity of bread dough increased with added broccoli powder. The moisture of the sponge cakes with added broccoli powder was higher than that of control. In the crumb color values, lightness (L) and redness (a) decreased upon broccoli powder addition, whereas yellowness (b) significantly increased (p<0.05). In the texture analysis hardness, cohesiveness, springiness and gumminess were reduced by addition of broccoli powder. When we evaluated the sensory characteristics of five subareas (color, flavor, texture, taste, and overall acceptability), 7% broccoli sponge cake showed the highest sensory properties except for flavor (p<0.05). Therefore, the results suggested that 7% broccoli sponge cake could be helpful in improving physical quality and taste.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.27 no.3
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• pp.122-129
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• 2017

For the production of a high-density ITO target, $In_2O_3$ powders with a small particle size and low agglomeration should be synthesized. The purpose of this study is to control the size and shape of the Indium hydroxide precursor which affects the properties of the $In_2O_3$ powder. As a starting raw material, Indium metal was dissolved in a Nitric acid ($HNO_3$) solution. The effect of concentration, pH, and temperature on the properties of Indium hydroxide was investigated using ammonium hydroxide as a precipitant. Crystallite size of each sample was analyzed by X-ray diffraction and the shape and the size of the powder was analyzed by transmission electron microscopy. As a result, the particle size of Indium hydroxide was increased with increase in the concentration of $In(NO_3)_3$ and the particle size and shape of the Indium hydroxide remained unchanged with increase in the pH of the solution. The particle size increased with increase in the precipitation temperature during precipitation.

• IMMUNE NETWORK
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• v.2 no.1
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• pp.60-64
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• 2002

Background: Chemotherapy with 5-fluorouracil (5-FU) has been one of the mainstay in breast cancer treatment. The effects of high dose 5-FU on cell cycle regulation were studied in breast caner cells. Methods: A breast cancer cell line MCF-7 was used. Protein expressions of G1/S cyclins, $p21^{Waf1/Cip1}$, cdk2, E2F1 and retinoblastoma were tested by western blot analysis. Immunoprecipitation and immune complex kinase assay were done for the assessment of E2F1/RB interacton and the activity of cdk2 respectively. Results: $p21^{Waf1/Cip1}$ expression was barely detectable in control cells. With addition of 5-FU level of $p21^{Waf1/Cip1}$ were induced and cyclin D3 level was decreased as cell growth decreases. In accordance with increased expression of $p21^{Waf1/Cip1}$, cyclin E-associated cdk2 kinase activity was reduced. Retinoblastoma protein (RB) became dephosphorylated and E2F-1 binding activity with RB was increased. Conclusion: In this situation of high concentration of 5-FU breast cancer cells tend to be G1/S cell cycle arrested. Overexpression of $p21^{Waf1/Cip1}$ and dephosphorylation of RB may mediate the effectss of 5-FU by inhibiting E2F-1 activity, which contributes to G1/S cell cycle arrest. These results could be an indicating landmark for further study of high dose chemotherapy with 5-FU.