• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.25 no.2
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• pp.125-128
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• 2012

We fabricated the electrolyte-insulator-semiconductor (EIS) devices with various high-k sensing membranes to realize a high quality pH sensor. The sensing properties of each high-k dielectric material were compared with those of conventional $SiO_2$ (O) and $SiO_2/Si_3N_4$ (ON) membranes. As a result, the high-k sensing membranes demonstrated better sensitivity and stability than the O and ON membranes. Especially, the $SiO_2/HfO_2$ (OH) stacked layer showed a high sensitivity and the $SiO_2/Al_2O_3$ (OA) stacked layer exhibited an excellent chemical stability. In conclusion, the high-k sensing membranes are expected to have excellent operating characteristics in terms of sensitivity and chemical stability for the biosensor application.

• Korean Journal of Mathematics
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• v.21 no.3
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• pp.311-318
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• 2013

We continue the study of power-Armendariz rings over IFP rings, introducing $k$-power Armendariz rings as a generalization of power-Armendariz rings. Han et al. showed that IFP rings are 1-power Armendariz. We prove that IFP rings are 2-power Armendariz. We moreover study a relationship between IFP rings and $k$-power Armendariz rings under a condition related to nilpotency of coefficients.

• Steel and Composite Structures
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• v.24 no.1
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• pp.1-13
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• 2017

In order to improve the deformation capacity of the high-strength concrete shear wall, five high-strength concrete shear wall specimens confined with high-strength rectangular spiral reinforcement (HRSR) possessing different parameters, were designed in this paper. One specimen was only adopted high-strength rectangular spiral hoops in embedded columns, the rest of the four specimens were used high-strength rectangular spiral hoops in embedded columns, and high-strength spiral horizontal distribution reinforcement were used in the wall body. Pseudo-static test were carried out on high-strength concrete shear wall specimens confined with HRSR, to study the influence of the factors of longitudinal reinforcement ratio, hoop reinforcement form and the spiral stirrups outer the wall on the failure modes, failure mechanism, ductility, hysteresis characteristics, stiffness degradation and energy dissipation capacity of the shear wall. Results showed that using HRSR as hoops and transverse reinforcements could restrain concrete, slow load carrying capacity degeneration, improve the load carrying capacity and ductility of shear walls; under the vertical force, seismic performance of the RC shear wall with high axial compression ratio can be significantly improved through plastic hinge area or the whole body of the shear wall equipped with outer HRSR.

• Korean Parent-Child Health Journal
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• v.17 no.1
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• pp.18-28
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• 2014

Purpose: The Purpose of this study was to investigate the relationships between resourcefulness and the health promoting behavior of high school girls. Methods: The subjects of this study consisted of 117 high school girls on S girls' high school. The data was analyzed with the SPSS computer program that includes descriptive statistics, mean, standard deviation, t-test, ANOVA, Pearson correlation coefficient and multiple regression analysis. Results: The mean age of subjects was 18.0 years old. The mean score of resourcefulness was 114.2. The most frequently practiced resourcefulness item was "By changing my way of thinking, I am often able to change my feelings about almost anything". The next most frequently practiced resourcefulness item was "My self-esteem increases when I am able to overcome a bad habit". There was no difference in the degree of resourcefulness with respect to the general characteristics. The mean score of health promoting behavior was 115.2. The group whose concerns over health was shown high health promoting behavior. The health education class group was shown high health promoting behavior. There was statistically significant positive correlation between resourcefulness and health promoting behavior of high school girls. Conclusion: The findings of this study provides promising evidence to construct further studies on the increasing health promoting behavior programs relating to high school girls. To increase health promoting behavior for high school girls, it is necessary to continue or possibly expand on existing health education programs.

• Journal of Korean Home Economics Education Association
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• v.12 no.1
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• pp.11-20
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• 2000

The purpose of this study was to investigate the correlations between the school neighorhood environment and adolescents’behaviors. A questionnare was distributed to 221 high school students from June 27. 1997 t해 July 16. 1997 in chonju. In this study SAS package was used. The statistical methods such as frequency. mean. analysis of variance. correlation analysis. multiple regression analysis and T-Test were applied. The result of this study were as follows. 1) The school neighborhood environment of B high school included much more problematic places than A high school in 20 minutes distance on foot. So B high school students visited problematic places more frequently than A high school students(p<.05). 2) Both of A high school students and B high school students didn’t be satisfied about the school neighborhood environment. The degree of satisfaction for school environment of A high school student was higher than that of B. (p<.001) The number of benefit facilities. the degree of cleanness, and the safety from automobiles positively influenced the satisfaction for school neighbor environment. while the number and visiting of harm facilities negatively in satisfaction. 3)The problematic behaviors of B high school students was higher than A high school students(p<.05)

• Proceedings of the Korea Concrete Institute Conference
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• 2006.05b
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• pp.549-552
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• 2006

Generally the ultra-high strength steel reinforced concrete has rich mix composition composed of high-strength type mineral admixtures and as a result of very low water-binder ratio(about under w/b=25%), it reveals ultra-high compressive strength(about over 100Mpa). Also, in order to obtain sufficient toughness after construction, we usually mix a large quantity steel fiber with ultra-high strength steel reinforced concrete therefore we must use proper mixer for workability. When we make the ultra-high strength steel reinforced concrete we need more long mixing time or much super-plasticizer than when we manufacture normal concrete. These bring about economical problems and performance deterioration. Therefore, in this study, in order to manufacture easily ultra-high strength steel reinforced concrete we develope a dedicated mixer for ultra-high strength steel reinforced concrete with high speed type. It carried out the examination for comparison between the dedicated and general type mixer, the analysis and counterplan of the point at issue when we manufacture ultra-high strength steel reinforced concrete by the dedicated mixer.

• Journal of Korean Association for Spatial Structures
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• v.6 no.3 s.21
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• pp.123-130
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• 2006

This study propose cutting body portion-high strength mechanical fasteners to improve deformation capacity of High strength bolts, which are the mechanical fasteners used for End-plate connections. And, we report that loading test results of steel beam-to-column connection using high deformation capacity-high strength bolts in accordance with SAC2000 loading program. As a result, the initial stiffness and the maximum strength of the connection using high deformation capacity-high strength bolts, are approximately the same in comparison with those of the end-plate connection using the existing high strength bolts. But the deformation capacity of the connection is more than twice as much as those.

• The Transactions of the Korean Institute of Power Electronics
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• v.23 no.3
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• pp.153-160
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• 2018

Recent trends in high-power-density applications have highlighted the importance of designing power converters with high-frequency operation. However, conventional LLC resonant converters present limitations in terms of high-frequency driving due to switching losses during the turn-off period. Switching losses are caused by the overlap of the voltage and current during this period, and can be decreased by reducing the switch voltage. In turn, the switch voltage can be reduced through a series connection of four switches, and additional circuitry is essential for balancing the voltage of each switch. In this work, a three-level LLC resonant converter that can operate at high frequency is proposed by reducing switch losses and balancing the voltages of all switches with only one capacitor. The voltage-balancing principle of the proposed circuit can be extended to n-level converters, which further reduces the switch voltage stress. As a result, the proposed circuit is applicable to high-input applications. To confirm the validity of the proposed circuit, theoretical analysis and experimental verification results from a 350 W-rated prototype are presented.

• Journal of Korean Home Economics Education Association
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• v.14 no.1
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• pp.55-73
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• 2002

The purpose of this study was to investigate the body cathexis and appearance management behaviors of the high school girls according to their demographic, physical, psychological. and school related variables. Data was obtained from 378 high school girls in Jeonju City by self-administered questionnaires from March to April. 2001. The results of this study were; 1. Body cathexis of high school twirls was relatively low, face and upper body cathexis were higher than other body parts. but lower-body and total body cathexis were low. 2. Body cathexis of high school twirls was in exact proportion to their parents' educational level total household income. and monthly pocket money. And it was higher in case of tall. light. external personality. higher self-esteem, art or physical high school girls. and the vocational high school twirls. with good academic records. and popular among friends. 3. High school girls showed higher appearance management behaviors such as bath, skin care. hair care. but they did risky appearance management behaviors such as drug use. diet. plastic cosmetic a tittle. The students in case of mother's higher educational level. more monthly income of household, more pocket money. external personalities. lower self-esteem, art or physical high school girls and the vocational high school girls, with good academic records, popular among friends showed higher appearance management behaviors .

• The Journal of Korean Physical Therapy
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• v.11 no.1
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• pp.71-77
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• 1999

The purpose of this study was to investigate the changes of muscle power by transcutaneous electrical nerve stimulation(TBNS), low frequency-low intensity(20pps, invisible muscle contraction intensity), low frequency-high intensity(20pps, visible muscle contraction), high frequency-low intensity(100pps, invisible muscle contraction intensity) and high frequency-high intensity(100pps, visible muscle contraction). The results were as follows. 1. Increased muscle power after 30 minutes of treatment by low frequency-low intensity TENS, and post-treatment 30 minutes muscle power were increased more than pre-treatment power(p<0.05). 2. Decreased muscle power after a 30 minute treatment by low frequency-high intensity TENS, and after the 30 minute treatment was terminated muscle power didn't recover to pre-treatment levels. 3. Decreased muscle power after 30 minute treatment by high frequency-low intensity TENS, but post-treatment 30 minute, muscle power didn't recover to pre-treatment levels. 4. The muscle power was remarkably decreased by high frequency-high intensity TENS after 30 minute treatment, in addition treatment terminated after 30minutes didn,t recover to pre-treatment power(p<0.05). 5. Lower frequency-low intensity TENS are good methods for preventing muscle fatigue, buty high intensity (TENS) are increased muscle fatigue. 6. Traditional TENS by high frequency-low intensity is a good method for preventing muscle fatigue.