• The Transactions of the Korean Institute of Electrical Engineers
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• v.33 no.11
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• pp.456-463
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• 1984

The fast-rising high-voltage pulse generation circuit system of a theta pinch is both theoretically and experimentally investigated. The idealized model of this circuit system is a hybrid circuit system composed of three parts: a lumped circuit part being consisted of a capacitor bank and a spark switch connected in series, another lumped circuit part being consisted of the Blumlein transmission line, whose end load is the pinch coil. the voltage difference between two ends of the pinch coil is formulated by analyzing this hybrid circuit system by means of the law of the signal propagation in the transmission line and Kirchhoff's laws. The expedient numerical method for computer calculation is developed to generate the pulse profile of the voltage difference across the pinch coil. The period of the experimentally measured main pulse is a fourth of the theoretical one neglecting the resistance of the pinch coil. We attribute this discrepancy to the modelling in the theoretical calculation that hte resistance and inductance of the spark switch and capacitor bank are assumed to be constant through discharge. Therefore, we can see that the rise time of the imploding magnetic-field pulse is mainly dependent on the spark switch and capacitor bank.

• Journal of the Korean Regional Science Association
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• v.13 no.2
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• pp.93-118
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• 1997

Main findings of this study are as follows. Time-space model of Korea for urban growth model is established. The variables of space model resulted in job and education, which both are significant at 0.01 level and positive. The effect of job and education on the urban growth are 0.76 and 0.29 respectively in average. the determinants for deciding the influences for job variable are income variable and price-level variable. Income variable contributes 68.66% and the direction is negative while contribution of price-level variable is 29.90% and the direction is positive. The determinants for education variable are income, unemployment and wage difference between university graduates and high school graduates. The contribution and the high school graduates. The contribution and the direction of each variable for education variable are 63.6% and positive for the unemployment variable, 15.99% and negative for the income variable and 13.75% and positive for the wage difference variable. This study in different from previous works in three ways. The first is to establish the time-space model which could consider the time and space factor simultaneously. The second is to build data bases which contain the data of almost every city and every year in Korea during the objective period, which make the analysis continuous. The third is that the general analytic framework for the study is macrosocial one rather than a behavioral one, which means the unit of analysis is the metropolitan community and each city occupies population actively through it's potential power such as jobs, education and so on rather than a city population is the passive result of migration.

• Journal of Biomedical Engineering Research
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• v.30 no.6
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• pp.529-534
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• 2009

One of the characteristics of the hearing impaired is that their frequency selectivity is poorer than that of the normal hearing. To compensate this, formant enhancement algorithms and spectral contrast enhancement algorithms have been developed. However in some cases, these algorithms fail to improve the frequency selectivity of the hearing impaired. One of the reasons is the acoustic masking among enhanced formants. In this study, we tried to enhance the formants based on the individual masking characteristic of each subject. The masking characteristic used in this study was minimum level difference (MLD) between the first formant to the second formant while acoustic masking was occurred. If the level difference between the two formants in each frame is larger than the MLD, the gain of the first formant was decreased to reduce the acoustic masking that occurred among formants. As a result of the speech discrimination test, using formant enhanced speeches, speech discrimination score (SDS) of the speeches having differently enhanced formants was significantly superior to SDS of the speeches having equally enhanced formants. It means that suppression of the acoustic masking among formants improve frequency selectivity of the hearing impaired.

• Proceedings of the Korean Society for Emotion and Sensibility Conference
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• 2002.05a
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• pp.270-273
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• 2002

The purpose of our study is to clarify about the influence that the visual information gives to the brain activities when pressure exerted the abdomen by waist belts. The visual information means that the some different visual information is inputted it, and the brain activity is evaluated by Electroencephalogram(EEG) measurements. At the same time, we carried out the sensory tests and verified about the relations between the psychological stress and the brain activities. There was a difference in change in the power of the $alpha$ wave with the eyes opened between man and woman. from the result of the sensory test, in the case of under the condition in the darkness with the eyes opened, there was no change in the a wave with before the pressure and after the pressure. In the other cases, $alpha$ wave changed in the same way with before the pressure and after the pressure. In the case of the visible and the invisible in pressure place, $alpha$ wave changed in the same way with before the pressure and after the pressure, but there was a difference in value. From the above, it isn't recognized that the visual information is influencing a pressure sense but some influences are given to it to the brain activities.

• Journal of Environmental Impact Assessment
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• v.20 no.2
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• pp.175-185
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• 2011

It is usual for energy consumption in accordance with facing and sitting direction of tower-type apartments to be calculated by the official statistics or computer simulation. Previous studies for energy consumption appear to be very limited due to the dependence on flat type of apartment. Acknowledging these constraints, an empirical study for a tower type apartment was conducted to demonstrate how a on-site indoor temperature measurement in spring can be used to assist in estimating the total energy consumption in terms of facing and sitting orientation specific settings. The results indicate that maximum temperature difference in spring was identified as $1.16^{\circ}C$ between south and eastern direction. It is known that raising $1^{\circ}C$ indoor temperature require 7% more energy consumption than normal. The $1.16^{\circ}C$ difference means that sitting direction of tower type apartment is a crucial explanatory variable as unit of analysis for energy consumption. It was demonstrated that the indoor temperature could be used effectively as an indicator to estimate energy consumption among various sitting direction of tower type apartments. It is anticipated that this research output could be used as a valuable reference to support more scientific and objective decision-making for facing and sitting orientation of tower type apartments.

• Journal of the Korean Ceramic Society
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• v.32 no.12
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• pp.1337-1348
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• 1995

TZP/SUS- and ZT/SUS-functionally gradient materials (FGM) were fabricated by pressureless sintering in Ar-atmosphere. The sintering defects such as warping, frustrum formation, splitting and cracking which originated from shrinkage and sintering behaviors of metal and ceramics different from each other could be controlled by the adjustment with respect to the particle size and phase type of zirconia. The residual stresses generated on the metal and ceramic regions in FGM were characterized with X-ray diffraction method, and relaxed as the thickness and number of compositional gradient layer were increased. The residual stress states in TZP/SUS-FGM have irregular patterns by means of the different sintering behavior and cracking at ceramic-monolith. While in ZT/SUS-FGM, compressive stress is induced on ceramic-monolith by the volume expansion of monoclinic ZrO2 at phase transformation. Also, compressive stress is induced on metal-monolith by the constraint of warping which may be created to the metal direction by the difference of coefficient of thermal expansions. As a consequence, it has been verified that the residual stress generated on FGM is dominantly influenced by the thickness and number of compositional gradient layer, and the sintering defects and residual stress can be controlled by the constraint of the difference of shrinkage and sintering behaviors of each component.

• The Research Journal of the Costume Culture
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• v.13 no.2 s.55
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• pp.255-268
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• 2005

The purpose of this study was to identify the physical characteristics of early adolescent girls by age. A total of 529 girls aged between 10 and 14 were measured and data were collected from 42 anthropometric and 41 photographic measurements per a person. SAS 8.1 was used in data analysis including means, standard deviations, t-test, Duncan test and frequency analysis. The results of this study are as follows. Most items related to height and length increased significantly at the age of $10\sim11$ and the growth slowed down at the age of $13\sim14$. As for items related to circumference, the growth rate was high at the age of $11\sim12$, and gradually slowed down afterward. Out of circumference items, hip circumference showed the highest growth rate. As for items related to thickness and width, thickness-related items grew quickly at the age of $10\sim12$, and among which bust thickness showed the highest growth rate. As for drop, the difference between hip circumference and waist circumference was most remarkable, but the difference between hip circumference and bust circumference was not large. The largest number of subjects had their menarche during the age of $11\sim12$ and, after menarche, their horizontal growth became active.

• The Journal of Korean Medicine
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• v.20 no.4
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• pp.62-68
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• 2000

This study was carried out to establish genetic understanding of three Sasang constitutions of Taeumin, Soeumin and Soyangin by Random Amplified Polymorphic DNA(RAPD) analysis. We have applied RAPD analysis to pooled DNA sample as a means to achieve rapid screening of large numbers of primers for their capacity to reveal constitutions-specific polymorphisms. From an initial 440 primers, 13 polymorphic primers between different constitutions were selected. Bandsharing(BS) and mean average percentage difference(MAPD) calculated within and between three constitutions using RAPD fingerprint data showed a higher degree of homogenity within than between the constitutions and indicated measurable divergence between three constitutions. The RAPD bandsharing(BS) values ranged from 0.71 to 0.73 between the three constitutions. The interconstitution divergence was narrower between Taeumin and Soeumin, than between the other paired constitution comparisons. The genetic distance between the three constitutions was measured by BS values. Genetic distance by RAPD analysis was 0.007 between Taeumin and Soeumin, and 0.014 between Soyang and the others. In conclusion, the genetic distance of Teaumin and Soumin was closer than that of Soyangin in the analysis of RAPD by using 440 primers.

• Journal of Astronomy and Space Sciences
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• v.35 no.1
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• pp.47-54
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• 2018

Moon mineralogy mapper ($M^3$)'s work proved that the moon is not completely dry but has some hydroxyl/water. $M^{3{\prime}}s$ data confirmed that the amount of hydroxyl on the lunar surface is inversely related to the measured signal brightness, suggesting the lunar surface is sensitive to temperature by solar insolation. We tested the effect of solar insolation on the local distribution of hydroxyl by using $M^3$ data, and we found that most craters had more hydroxyl in shade areas than in sunlit areas. This means that the local distribution of hydroxyl is absolutely influenced by the amount of sunshine. We investigated the factors affecting differences in hydroxyl; we found that the higher the latitude, the larger the difference during daytime. We also measured the pyroxene content and found that pyroxene affects the amount of hydroxyl, but it does not affect the difference in hydroxyl between sunlit and shaded areas. Therefore, we confirmed that solar insolation plays a significant role in the local distribution of hydroxyl, regardless of surface composition.

• Journal of Korean Public Health Nursing
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• v.20 no.2
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• pp.183-194
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• 2006

Purpose: The purpose of this study was to investigate student nurses' knowledge and attitude related to the elderly. Method: The data were collected from 519 student nurses studying in university by means of a structured questionnaire. The data were analyzed using descriptive analysis, t-test, one-way ANOVA, and Pearson correlation analysis by SPSS version 10. Results: The average score of the respondents' knowledge of the elderly was 12.02(${\pm}2.77$) out of 25. The average score of the respondents' attitude toward the elderly was 80.09(${\pm}11.69$) out of 140. There was a statistically significant difference in the respondents knowledge of the elderly depending on their degree of preference for giving nursing care to the elderly (F=7.534, p=.001). There was a statistically significant difference in the respondents attitude toward the elderly depending on their degree of preference for giving nursing care to the elderly (F=23.167, p=.000), possession of living grandparents (F=6.174, p=.002), and degree of interaction with elderly (t=5.661, p=.000). Student nurses' knowledge and attitude related to the elderly were significantly correlated. Conclusion: It is necessary to develop a program for continuous teaching and education that will help increase student nurses' knowledge of the elderly and thereby positively change their attitude toward the elderly.