• Journal of dental hygiene science
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• v.12 no.3
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• pp.287-294
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• 2012

The aim of this study was to investigate the effect of standardized oral health care program by dental hygiene school students. Target population was 100 University students who attended standardized oral health care program by a dental hygiene school students. Present study was conducted during first and second semester in 2011 at E dental hygiene school. We analysed students' oral health related knowledge, attitude, behavior, and self-oral hygiene care ability after the program. Univariate analysis, Chi-square test and paired t-test were conducted using SAS version 9.2. University students' who attended standardized oral health care program by dental hygiene school students oral health related knowledge, attitude, behavior, and self oral-hygiene care ability were significantly improved whether they have attended oral health related lectures or not(p<.05). It is recommended provide standardized oral health care program to university students by dental hygiene school students to promote their oral health related knowledge, attitude, behavior, and self-oral hygiene care ability.

• Elastomers and Composites
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• v.48 no.3
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• pp.190-194
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• 2013

In this study, sebacic acid made from castor oil was used as monomer with isophthalic acid and glycols for polyester polyol synthesis. Polyurethane adhesive was synthesized from the various polyester polyol. From the result of adhesion strength test, polyester polyol made from sebacic acid showed better adhesive force than that of adipic acid due to higher cohesive energy. Branched glycol containing methyl group represented better adhesion than linear glycol. In the chain extender, adhesion strength increased going from PG, EG, BD. From the measurement of TGA, BD showed the best heat stability, and followed by PG, EG. Glass transition temperature increased in the order PG, EG, BD by the result of DMA.

• Human Ecology Research
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• v.55 no.4
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• pp.385-397
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• 2017

This study assessed the nutrient intake for Korean adolescents using the estimated usual intake. The usual intake of 1,763 adolescents aged 12-17 years old was estimated from one-day 24-hour recall data in the 2010-2012 Korean National Health and Nutrition Survey. The nutrient intakes of four groups according to sex (male and female) and age (12-14 and 15-17 years old) were then assessed in reference to the 2015 Dietary Reference Intakes for Koreans. For macronutrients, the proportions of subjects below and above the Acceptable Macronutrient Distribution Ranges (AMDR) were calculated. The Estimated Average Requirement (EAR) cut-point method was used to assess insufficient intakes of protein, vitamin C, thiamin, riboflavin, niacin, calcium, phosphorus, and iron; the full probability approach was used to assess the insufficient intake for iron among females. The proportions of subjects over the Tolerable Upper Intake Levels for vitamin C, niacin, calcium, phosphorus, and iron and the proportions over the Intake Goal for sodium were calculated to assess excessive intake. The proportions of subjects above AMDR for carbohydrates ranged from 22.5% to 38.0% by group. The proportions of subjects by group with insufficient intake for vitamin C, riboflavin, calcium, phosphorus, and iron ranged 29.1-39.7%, 22.5-34.3%, 73.1-89.3%, 14.3-43.6%, and 23.2-55.5%, respectively. The proportions of subjects by group with excessive intake for sodium ranged from 91.5% to 99.3%. The results of this study represent important basic information to establish nutritional standards for school lunches as well as to decide on relevant nutrition policies for adolescents.

• Korean Chemical Engineering Research
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• v.43 no.2
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• pp.215-221
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• 2005

A Fe-containing mesoporous silica (Fe-MCM-41) in which part of Si in the framework was replaced by Fe(Si-O-Fe) has been successfully prepared using $Fe^{3+}$ salt by a direct synthesis route. Physical properties of the material were characterized by XRD, $N_2$ adsorption, SEM/TEM, UV-vis and FT-IR spectroscopies. Fe-MCM-41 exhibited high catalytic activity in phenol hydroxylation using $H_2O_2$ as oxidant, giving phenol conversion of ca. 60% at $50^{\circ}C$ [phenol : $H_2O_2$ = 1:1, water solvent]. Fe-MCM-41 was also applied to the growth of CNTs, utilizing a thermal-CVD reactor using acetylene gas, which demonstrated that multi-wall CNTs could be prepared efficiently using the Fe-MCM-41 catalyst.

• Geophysics and Geophysical Exploration
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• v.19 no.2
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• pp.97-104
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• 2016

Small to large earthquakes have been reported in Gyeongju and its vicinity in southeast Korea during historical period as well as instrumental observation period. We identified and located more than 300 earthquakes that occurred between January 2010 and December 2014 in a $20km{\times}30km$ area, but were unreported because of their small magnitudes. We used the Joint Hypocenter Determination (JHD) method to minimize the influence of the differences between the actual earth structure and 1-D velocity model for earthquake locations. The potential relationship between the previously reported Quaternary faults and the earthquake hypocenters was investigated. Many micro-earthquakes were found to be located in the southern segment of the Yeonil Tectonic Line, the Seokup fault, and the Waup basin boundary faults.

• Solar Energy
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• v.17 no.4
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• pp.13-22
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• 1997

Drag reduction produced by the dilute solution of polymer under turbulent flow in a rotating disk apparatus(RDA) was investigated in this study for the purpose of potential application to the Ocean Thermal Energy Conversion(OTEC) system. Four different molecular weights of poly(ethylene oxide)(PEO) were used as drag reducing additives, and synthetic seawater was adopted as a solvent. Experiments were undertaken to observe the dependence of drag reduction on various factors such as polymer molecular weight, polymer concentration and the rotating speed of the disk. The concentration dependence on the drag reduction of this polymer system was shown to obey an empirical drag reduction equation of the Virk's universal correlation.

• Journal of Digital Convergence
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• v.13 no.5
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• pp.269-276
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• 2015

In order to examine the relationship between cholesterol level on serum and depression in Korean adults, this study used data of the fourth Korea National Health and Nutrition Examination Survey (KNHANES). 834 persons with depressive symptoms were selected as an index group and 3,317 persons without depressive symptoms as a control group, and odds ratios were calculated by multivariate logistic regression. As a result, odds ratio of depressive symptoms was higher in low LDL group (OR=6.435, 95% CI; 2,358-17.557) than in high LDL group adjusted after monthly income, marital status, period of education, occupation, smoking status, and physical activity. Etiopathogenic mechanism must be found by convergent study in the future.

• Polymer(Korea)
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• v.33 no.4
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• pp.364-370
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• 2009

The curing kinetics and mechanical properties of siloxane-diaminodiphenylmethane (ETSO-DDM) on the two kinds of bisphenol (BPH) system which are DGEBA and DGEBF were investigated with the different contents of ETSO. To investigate the curing kinetics of the ETSO-DDM/BPH systems, differential scanning calorimeter (DSC) was used. The mechanical properties of ETSO-DDM/BPH systems were also examined by universal testing machine (UTM), tensile test and flexural test. From experimental results, the activation energies and mechanical properties of ETSO-DDM/BPH were improved with the decrease contents of ETSO. This was due to the high cross-linking density made from short length of ETSO-DDM, resulting in improving the mechanical inter-locking between ETSO-DDM and BPH in these systems.

• Korean Journal of Health Education and Promotion
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• v.30 no.1
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• pp.83-93
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• 2013

Objectives: The objective of this study was to assess the gender differences in the relationship between alcohol use behaviors and the risk of metabolic syndrome among Korean adult population. Methods: Data from the Korean National Health and Nutrition Examination Survey (5th, 2010) was analyzed. Using the Alcohol Use Disorders Identification Test, subjects were classified into 4 groups including non-drinking, low-risk drinking, medium-level alcohol problem, and high-level alcohol problem group. Metabolic syndrome and its components were compared among the alcohol behavior groups by gender. Results: The odds ratio vs. non-drinking group for metabolic syndrome was significantly higher in male medium and high-level alcohol problem group. In female, high-level alcohol problem group showed significantly higher odds ratio for metabolic syndrome. Blood pressure and HDL-cholesterol were likely to be higher with the excessive drinking behaviors in both men and woman. Triglyceride level in men was significantly higher in the medium and high-level alcohol problem group than non-drinking group. Although fasting glucose level did not show differences among drinking groups, the odd ratios vs. non-drinking group for the hyperglycemia (${\geq}$ 100mg/dl) were significantly higher in female drinking groups. Conclusions: Problematic alcohol drinking is likely to increase the risk of metabolic syndrome in Korean adults.

• Information and Communications Magazine
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• v.30 no.6
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• pp.3-12
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• 2013

와이파이(Wi-Fi) 기술은 무선 데이터 트래픽 폭증에 따라 사업자에게는 트래픽 우회, 이용자에게는 통신요금 부담 완화의 대안으로 중요성이 부각되고 있다. 이에 우리나라에서는 이동 통신사업자 중심으로 와이파이를 지속적으로 확충하여 세계에서 가장 많은 와이파이 존(zone)을 보유한 국가가 되었다. 그러나, 특정 장소에 와이파이를 중복적으로 구축함에 따라 투자 효율성과 서비스 품질이 저하되고, 서민 소외계층 이용시설에는 구축이 상대적으로 저조하다는 문제점도 상존하는 상황이다. 본 고에서는 우리나라의 와이파이를 효율적으로 확산하고자 3가지 개선방향을 제시하였다. 첫 번째는 경쟁구축 차별화에서 투자효율화 공동이용 전략으로의 전환이며, 두 번째는 수도권 도시 지역 중심에서 서민 소외계층 지역으로 확산시키는 것이다. 마지막으로 Legacy Wi-Fi에서 차세대 Wi-Fi로 전환하는 것을 주요 방향으로 제시하였고, 이러한 개선방향을 바탕으로 4가지 전략을 제시하였다. 첫 번째 전략은 PPP(Public Private Partnership) 방식의 공공와이파이(Public Wi-Fi) 구축으로, 전통시장, 복지시설 등 서민 소외계층이 주로 이용하며 와이파이 구축이 열악한 이용시설에 정부, 지자체, 통신사가 공동으로 투자하여 공공와이파이를 구축함으로써 정보격차를 해소시키는 것이다. 두 번째 전략은 통신사의 와이파이 개방을 통한 공용화로, 통신사가 공공장소에 기 구축한 와이파이의 개방을 유도함으로써 중복투자 및 서비스 품질 저하 방지 등 공용화를 통한 투자효율성을 제고하는 것이다. 세 번째 전략은 차세대 와이파이 선도도입을 통한 글로벌 경쟁력 강화로, LTE 등 이동통신 기술의 급속한 보급에 맞추어 무선랜 서비스의 경쟁력 확보를 위해 광대역화 광역화를 선도하고, 응용서비스 발굴 및 산업활성화를 유도하는 것이다. 마지막은 공공와이파이 인식제고로, 공공와이파이의 이용편의성과 홍보활동을 강화하는 것이다. 이러한 전략의 핵심은 공공와이파이 확산과 차세대 와이파이 선도 도입으로, 이를 통하여 통신복지를 실현하고, 산업활성화를 통한 국민행복을 실현시키는 것에 대하여 간략히 설명한다.