• Proceedings of the KIEE Conference
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• 1992.07a
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• pp.205-210
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• 1992

The power flow calculations are the most important and powerful tools in the various studies of power system engineering. Newton-Raphson method, among the various power flow calculation techniques, is normally used due to its rapidness of numerical convergency. In the conventional Newton-Raphson method, however, there are some unrealistic assumptions, in which all the system power losses are considered to be supplied by the slack bus generator. Introducing the system power loss formula and augmenting the conventional Newton-Raphson power flow method, we can relieve the unrealistic assumption and improve the performance of power flow calculation. In this study, A new approach for handling the losses and augmenting the conventional power flow problem is proposed. The proposed method estimates the increamental changes of active power on each generation bus with respect to the change of total system power losses and the estimated value are used to update the slack bus power. If some studies for more theoritical investigations and verifications are followed, the proposed approach will show some improvement of the conventional method and give lots of contribution to increase the performance of power flow techniques in power systems engineering.

• Journal of Environmental Science International
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• v.16 no.5
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• pp.561-569
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• 2007

This study used SCS-CN method to estimate the real recharge of the study area which is one of the most reasonable techniques to estimate groundwater recharge when there is no available runoff data in a watershed. From the results of tile real recharge analysis for the study area using SCS-CN method, it was analyzed that the year 1994 when the drought was severe shotted the lowest recharge of 106.3mm with recharge rate of 12.4%, and the highest recharge of 285.6mm with recharge rate of 21.8% occurred in 1990. Yearly average recharge of 213.2mm was obtained, and tile average recharge rate was 16.9%/year. KOG-FLOW model which has powerful post process functions consists of setting environments for input parameters in Korean language, and help function is added to each input data. Detailed information for each parameter is displayed when the icon is placed on the input parameters, and geologic boundaries or initial head data for each layer can be set easily on work sheet. The relative errors (R. E.) for each model's observed values and calculated values are $0.156{\sim}0.432$ in case of KOG-FLOW, and $0.451{\sim}1.175$ in case of WINFLOW, therefore it is known that KOG-FLOW model developed in this study produced results compared to observed head values.

• Child Health Nursing Research
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• v.10 no.2
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• pp.205-216
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• 2004

Purpose: The purpose was to investigate the factors influencing alcohol consuming behavior of the female university students to provide the basic data for a nursing intervention program to improve health and prohibit of alcohol consuming behavior. Method: The subjects were 134 female university students, studying at K university and K educational university in Chungnam province from April 1 to 20, 2002. The instruments were the alcohol consuming behavior scale, that is drinking intensity score, and alcohol problem developed by Shin(1998), refusal self-efficacy scale by Aas et. al.(1995), alcohol expectancy by Goldman at. al.(1989), TPQ scale by Cloninger(1991), depression scale modified by Shin(1977) using Zung(1965)' tool, family cohesion scale by Olson at. al.(1983). The data were analyzed using descriptive statistics, Pearson correlation coefficient, canonical correlation and stepwise multiple regression. Result: The most powerful predictor of alcohol consuming behavior was influence of friends-drinking(21.0％). A combination of economic status(8.0％), and personality of novelty seeking(3.0％), accounted for 32.0％ of the variance in alcohol consuming behavior. Conclusion: I recommended that economic status, influence of friends drinking frequently, and personality of novelty seeking were contained of the developing nursing intervention program for decreasing the alcohol consuming behavior in female university students.

• Journal of East-West Nursing Research
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• v.17 no.2
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• pp.149-155
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• 2011

Purpose: The purpose of this study was to examine the effect of depression and self-efficacy on health promotion behavior in elders living alone in rural area. Methods: This was a descriptive study. The survey participants were 369 elders living alone in rural area. The period of time for data collection was from June 23 to August 7, 2008. Data were analyzed by descriptive statistics, independent-samples t-test, ANOVA, pearson's correlation coefficient, and stepwise multiple regression. Results: Depression was found to have a statistically negative correlation with health promotion behavior. Self-efficacy was found to have a statistically positive correlation with health promotion behavior. Stepwise multiple regression analysis revealed that the most powerful predictor of health promotion behavior was depression. Depression, self-efficacy, number of chronic disease, and economic status accounted for 35.2% of the variance. Conclusion: It is necessary to prepare health promotion programs that can reduce depression level and improve self-efficacy in elders living alone in rural area.

• Journal of East-West Nursing Research
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• v.18 no.2
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• pp.104-110
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• 2012

Purpose: The purpose of this study was to investigate the relationship between health promotion behavior and aggression among teenagers. Methods: This was a descriptive study. The survey participants were 502 teenagers. Data was collected from September 7 to October 5, 2009. The data was analyzed using descriptive analysis, independent-samples t-test, ANOVA, and stepwise multiple regression. Results: The average age of participants was 14.4. Fourty eight percent of participants were male, 67.3% were middle-class house, 23.1% were above overweight, 6.3% were daily smoker, 43.5% were occasional drinker. Age was found to have a statistically negative correlation with health promotion behavior, while having positive correlation with aggression. There were significant differences in teenagers' health promotion behavior and aggression according to their smoking and drinking experiences. Personal regression was identified as the most powerful predictor of teenager's aggression. Personal relationship, nutrition accounted for 15.7% of the variance. Conclusion: It is necessary to consider a program related to teenager's health promotion for reduction of their aggression level.

• BMB Reports
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• v.48 no.8
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• pp.445-453
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• 2015

Endoplasmic Reticulum (ER) is an organelle where most secretory and membrane proteins are synthesized, folded, and undergo further maturation. As numerous conditions can perturb such ER function, eukaryotic cells are equipped with responsive signaling pathways, widely referred to as the Unfolded Protein Response (UPR). Chronic conditions of ER stress that cannot be fully resolved by UPR, or conditions that impair UPR signaling itself, are associated with many metabolic and degenerative diseases. In recent years, Drosophila has been actively employed to study such connections between UPR and disease. Notably, the UPR pathways are largely conserved between Drosophila and humans, and the mediating genes are essential for development in both organisms, indicating their requirement to resolve inherent stress. By now, many Drosophila mutations are known to impose stress in the ER, and a number of these appear similar to those that underlie human diseases. In addition, studies have employed the strategy of overexpressing human mutations in Drosophila tissues to perform genetic modifier screens. The fact that the basic UPR pathways are conserved, together with the availability of many human disease models in this organism, makes Drosophila a powerful tool for studying human disease mechanisms. [BMB Reports 2015; 48(8): 445-453]

• KSCE Journal of Civil and Environmental Engineering Research
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• v.13 no.5
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• pp.201-208
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• 1993

The emergence of the Global Positioning System(GPS) with its benefits of speed and economy now offers an opportunity to analyse, strengthen, densify and constitute the control network, in addition to providing mapping, cadastral and engineering control under the unfavorable conditions. This research aims at the using of GPS compared to conventional geodetic positioning techniques in Korean primary control networks. A GPS test network of 10km baselines, which is measured and analysed by Wild GPS-System 200, are compared to the distances from EDM and official coordinates, and relative GPS heights are transformed to the height differences on the mean sea level. The results of this study confirms that using GPS merely as a new type of instrument is the most powerful method for the densification of the control points retaining existing networks and existing computational procedures.

• The Journal of Korean Medicine
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• v.29 no.3
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• pp.124-130
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• 2008

Herbal plants or traditional Oriental medicine have been considered as a potential resource of new drug development worldwide. However, traditional Korean medicine has given little effort to the field of new drug development. This study reports on a plant-derived hepatotherapeutic drug, silymarin, which has been popularly used in many countries. It was discovered as an active compound from Silybum marianum (milk thistle) which has been known as a medicinal plant having hepatoprotective properties in both European and Asian countries. While it has been used as an herbal prescription in Asia, its active compounds or scientific mechanisms were intensively studied in Europe. Currently, silymarin is one of the most powerful herbal extracts in the world, and its usage is being expanded to many other medical purposes. This report would be helpful for providing an informative example of herbal-derived drug development to Oriental doctors or scientists in the Oriental medicinal field.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2009.04a
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• pp.302-309
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• 2009

Nowadays, the construction sites are growing in city every year, so complaints for construction noise have increased more and more. To analyze this noise scientifically, construction noise prediction program was developed in 1998 and 2005 but it is too difficult to apply program in field because there is few soundproof facilities and it can't understand the coordinate system and so on. The aim of this study is to develop noise prediction program to apply in construction sites. For this, the problems of existing program was analyzed and survey was performed to get requestion of field overseer and upgraded program. To get reliability of program, it was compared with sound measurement value in field. As a result, construction sound prediction program have various soundproof facilities data than existing program. It can also analyze multi receiver point at the same time for several construction machinery. Most of all, it is more powerful to set receiver or source in the axis of X, Y, Z. so program user can make use of it easily. An average of difference is -0.9$\sim$1.8dB.

• Biomolecules & Therapeutics
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• v.3 no.2
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• pp.104-110
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• 1995

Arachidonic acid (AA, C20 : 4, $\omega$-6) and eicosapentanoic acid (EPA,C20 : 5, $\omega$-3), which are polyunsaturated fatty acids forming eicosanoids, were tested for their effects on blood pressure in Wistar rats and SHR. AA is the most important precursor for the biosynthesis of eicosanoids which include the prostaglandins, prostacyclin (PGI$_2$), thromboxane $A_2$ (TXA$_2$) and the leukotriens. TXA$_2$is a potent vasoconstrictor and a powerful inducer of platelet aggregation causing myocardial infarction and hypertention. In contrast, PGI$_2$ induces vasodilation and inhibits platelet aggregation. In this study, AA markedly increased blood pressure, but its effect was antagonized by both EPA, a structural analog of AA, and dazmegrel, a TX synthetase inhibitor. Also, AA enhanced the antihypertensive effects of hydralazine and captopril, and EPA reduced TXA$_2$ production. These results indicate that the hypotensive effects of EPA might be closely related to the decrease in TXA$_2$ biosynthesis due to competitive inhibition by structural similarity of the EPA to the AA, the precursor of TXA$_2$.