• Korean journal of food and cookery science
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• v.2 no.1
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• pp.11-16
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• 1986

Physicochemical properties and fatty acid composition of 12 randomly selected Korean margarines were determined, which were stored within one month since manufactured. Average moisture and fat contents of margarines were 15.09% ana 77.92% respectively. Melting point was ranged from 33.23$^{\circ}C$ to 42. 13$^{\circ}C$. Acid value and peroxide value were very low. iodine value was ranging from 59.65 to 86. 05. As a result of cluster analysis using the data of fatty acid composition, margarines divided into two groups according to their package condition, soft and hard type, were also classified into the same two groups. This probably implies that the raw materials of margarines between two groups were not the same. O1eic acid (18:1) and palmitic acid (16:0) in soft and hard type margarines respectively were the highest. Linoleic acid (18 : 2) contents showed large differences among margarines. Most of the margarines had little linolenic acid (18:3) . Generally essential fatty acid contents of Korean margarines were higher than those of the past but they didn't reach the levels of margarines made in some foreign countries.

• Journal of dental hygiene science
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• v.13 no.3
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• pp.281-289
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• 2013

The purpose of this study is to find out potential factors associated with the quality of life in South Korean senior people, on the basis of their oral health, so that it may provide basic reference materials in developing and assessing national policies for improving the quality of life in senior people. The data of 3,882 senior citizens who were at the Western age of 65 and up and got a dental checkup were selected from the first-, second- and third-year raw data of the 4th National Health and Nutrition Survey that were conducted from July 2007 to December 2009. And the statistical package SPSS 19.0 was employed to analyze the selected data. The findings of the study were as follows: The senior citizens whose remaining tooth was larger in number and who didn't need partial or full denture lead a better quality of life. Therefore, dental loss without any prosthetic appliance has significant negative effects on the quality of life in senior people, so it is urgently demanded to try to increase the number of remaining teeth and apply dental prosthesis to senior people for recovery of their oral health.

• Journal of Korean Dental Science
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• v.3 no.2
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• pp.20-25
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• 2010

Aim : This study was conducted to assess the oral health status of deaf and mute children attending special school. Materials and Methods : A cross-sectional descriptive survey was conducted among 137 deaf and mute children with ages ranging from 7 to 18 years. A total of 76 males (55.47%) with mean age of $14.2{\pm}4.5$ and 61 females (44.53%) with mean age of $13.8{\pm}4.2$ years and studying in a school for deaf and mute children in Warora were considered. Data were collected using a standard method recommended by WHO for the oral health survey in 1977. Oral health status was assessed using OHIS, Loe and Sinless, and CPI Index along with DMFT and DMFS Index. Gingival position was considered for measuring attachment loss. Statistical analysis was performed using the SPSS software package (version 17.0). Results : The mean DMFT was found to be $2.53{\pm}1.72$, and mean DMFS, $3.37{\pm}3.16$. The prevalence of dental caries was pegged at 35.32%, with mean OHIS score at $1.49{\pm}0.76$. Overall gingival index among deaf and mute children was $0.81{\pm}1.4$, whereas that for the upper arch and lower arch was $0.92{\pm}0.84$ and $1.19{\pm}0.95$, respectively. The mean score for the CPI Index among deaf and mute children was found to be $0.42{\pm}0.32$. Gingival clinical attachment loss was found to be $0.26{\pm}0.15mm$. Conclusion : These findings suggest that children with hearing disabilities can also have good oral hygiene comparable to normal individuals of the same age group. These results may be attributed to the fact that the study sample was taken from a single school of a private organization with a well-equipped dental setup.

• The Research Journal of the Costume Culture
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• v.20 no.2
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• pp.251-262
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• 2012

This research aimed to examine an advertising location according to consumer involvement about internet search advertising and advertising effect according to advertising forms. This research carried out a questionnaire survey from May 25, 2011 for seven days with the target of men and women at the age of 20s-30s who tried search advertising in Seoul and capital area, and 519 copies were used for final analysis. For analysis of collected materials, the reliability test, factor analysis, $t$-test, regression analysis and ${\chi}^2$ test were executed by using statistical package SPSS 16.0. The results are as follows. First, it appeared that consumer's clothing involvement, advertising involvement, advertising location and advertising forms had an influence on site attitude and clicking intention. Consumers of high clothing involvement, high advertising involvement and upper end advertising appeared to have high site attitude and clicking intention. Second, all consumers of the low and high clothing involvement and upper end advertising appeared to prefer the upper end advertising. It appeared that consumers of low advertising involvement prefer lower end advertising, and consumers of high advertising involvement prefer the upper end advertising at an advertising location according to clothing involvement. Accordingly, it is important that the search advertising exposes advertising in the upper end, and that should use an advertising phrase capable of giving trust to consumers. As the text advertising had high site attitude and clicking intention in the advertising forms, consumers should pay attention to the advertising phrase.

• Journal of Electrochemical Science and Technology
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• v.2 no.3
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• pp.146-151
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• 2011

The formation of Li-Si-O phases, $Li_4SiO_4$ and $Li_2SiO_3$ from the starting materials SiO and $Li_2O$ are analyzed using Vienna Ab-initio Simulation (VASP) package and the total energies of Li-Si-O compounds are evaluated using Projector Augmented Wave (PAW) method and correlated the structural characteristics of the binary system SiO-$Li_2O$ with experimental data from electrochemical method. Despite $Li_2SiO_3$ becomes stable phase by virtue of lowest formation energy calculated through VASP, the experimental method shows presence of $Li_4SiO_4$ as the only product formed when SiO and $Li_2O$ reacts during slow heating to reach $550^{\circ}C$ and found no evidence for the formation of $Li_2SiO_3$. Also, higher density of $Li_4SiO_4$(2.42 g $ml^{-1}$) compared to the compositional mixture $1SiO_2-2Li_2O$ (2.226 g $ml^{-1}$) and better cycle capacity observed through experiment proves that $Li_4SiO_4$ as the most stable anode supported by better cycleabilityfor lithium ion battery remains as paradox from the point of view of VASP calculations.

• Transactions of the Korean hydrogen and new energy society
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• v.23 no.4
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• pp.300-309
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• 2012

Long endurance is a key issue in the application of unmanned aerial vehicles. This study presents feasibility test results when fuel cell system as an alternative to the conventional engine is applied for the power of the UAV after the 150W fuel cell system is developed and packaged to the 1/4 scale super cub airplane. Fuel cell system is operated by dead-end method in the anode part and periodically purged to remove the water droplet in flow field during the operation. Oxygen in the air is supplied to the stack by the two air blowers. And fuel cell stack is water cooled by cooling circuit to dissipate the heat generated during the fuel cell operation. Weight balance is considered to integrate the stack and balance of plant (BOP) in package layout. In flight performance test, we demonstrated 4 times standalone take-off and landing. In the laboratory test simulating the flight condition to quantify the energy flow, the system is analyzed in detail. Sankey diagram shows that electric efficiency of the fuel cell system is 39.2%, heat loss 50.1%, parasitic loss 8.96%, and unreacted purged gas 1.67%, respectively compared to the total hydrogen input energy. Feasibility test results show that fuel cell system is high efficient and appropriate for the power of UAV.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.26 no.8
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• pp.614-619
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• 2013

Recently, remote phosphor is reported for white LED enhancing of phosphor efficiency compared with conventional phosphor-based W-LED. In this study, Remote phosphor was produced by screen printing coating on glass substrate with phosphor contents rated paste and heat treatment. The paste consists of phosphor, lowest softening glass frit and organic binders. Remote phosphor can be well controlled by varying the phosphor content rated paste. After mounting remote phosphor on top of blue LED chip, CCT, CRI, and luminance efficiency were measured. The measurement results showed that CCT, CRI, and luminance efficiency were 6,645, 68, and 1,16l m/W in phosphor 80 wt.% remote phosphor sintered at $600^{\circ}C$.

• The Korean Journal of Community Living Science
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• v.16 no.4
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• pp.15-24
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• 2005

We investigated the changes of volatile flavor components from Codonopsis lanceolata, which were packed in woven polypropylene(WP) film or low density polyethylene(LDPE) film and stored for 15 and 30 days at refrigerated($2{\∼}4^{\circ}C$ ) or room($18{\∼}20^{\circ}C$) temperature. A hundred and sixty seven volatile flavor components in the fresh C. lanceolata were identified by GC/MS analysis. When determining the flavor components from C. lanceolata cultivated on a wild hill and stored at 4 conditions for 30days, six volatile components such as 1-hexadecene, 2,6-dimethyl-2-octanol, 2-methyl-2-dodecanol, $\alpha$-guaiene, $\delta$-cadinene and trans-2-hexen-1-ol were detected as common components of all stored samples, and The types of common flavor components of C. lanceolata were different according to storage conditions. The numbers were 16 from refrigerated, 7 from room temperature stored, and 10 components from WP or LDPE packed conditions, respectively. The total peak area ratio of the major 10 compounds were $52.0{\∼}86.8\%$, and the percentage of trans-2-hexen-1-ol, which was the only common compound among the major 10 components, was the highest as $26.4{\∼}68.1\%$ The major flavor profile, describe by highly trained panel, were green, aldehydic, earthy and camphoreous. As the result from sensory evaluation, the freshness of C. lanceolata was maintained better by controlling storage temperature rather than selection of package materials. The best condition for characteristic flavor of C. lanceolata was packing with LDPE and chilling.

• Food Science and Preservation
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• v.10 no.4
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• pp.574-583
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• 2003

There have been a lot of research efforts on development of active food packaging structures and materials in the form of plastic films and containers, along with investigating novel polymers and bioactive compounds for packaging purpose, in order to improve storage stability and safety of foods during distribution and sale. Recently, great interests focus on antimicrobial package films, as an active packaging system, made from synthetic plastic polymer% and natural biopolymers containing various antimicrobial substances for food packaging applications. In this active system, substances are slowly released onto the food surface. However, antimicrobial activity as well as physical properties of the films can be significantly influenced by several factors such as polymer matrix, antimicrobial compounds, and interactions between polymers and compounds. Thus, this study reviews present status of antimicrobial food packaging films in overall performance aspects including types of polymers and active substances, test for antimicrobial activity, and changes in mechanical and antimicrobial properties by preparation method.

• The Journal of Advanced Prosthodontics
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• v.5 no.2
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• pp.110-117
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• 2013

PURPOSE. Polymethyl methacrylate (PMMA) is the most commonly used denture base material despite typically low in strength. The purpose of this study was to improve the physical properties of the PMMA based denture base resins (QC-20, Dentsply Ltd., Addlestone, UK; Stellon, AD International Ltd, Dentsply, Switzerland; Acron MC; GC Lab Technologies Inc., Alsip, Japan) by copolymerization mechanism. MATERIALS AND METHODS. Control group specimens were prepared according to the manufacturer recommendations. In the copolymer groups; resins were prepared with 5%, 10%, 15% and 20% acrylamide (AAm) (Merck, Hohenbrunn, Germany) content according to the moleculer weight ratio, respectively. Chemical structure was characterized by a Bruker Vertex-70 Fourier transform infrared spectroscopy (FTIR) (Bruker Optics Inc., Ettlingen, Germany). Hardness was determined using an universal hardness tester (Struers Duramin, Struers A/S, Ballerup, Denmark) equipped with a Vickers diamond penetrator. The glass transition temperature ($T_g$) of control and copolymers were evaluated by Perkin Elmer Diamond DSC (Perkin Elmer, Massachusetts,USA). Statistical analyses were carried out using the statistical package SPSS for Windows, version 15.0 (SPSS, Chicago, IL, USA). The results were tested regarding the normality of distribution with the Shapiro Wilk test. Data were analyzed using ANOVA with post-hoc Tukey test (P<.01). RESULTS. The copolymer synthesis was confirmed by FTIR spectroscopy. Glass transition temperature of the copolymer groups were higher than the control groups of the resins. The 10%, 15% and 20% copolymer groups of Stellon presented significantly higher than the control group in terms of hardness. 15% and 20% copolymer groups of Acron MC showed significantly higher hardness values when compared to the control group of the resin. Acrylamide addition did not affect the hardness of the QC-20 resin significantly. CONCLUSION. Within the limitation of this study, it can be concluded that copolymerization of PMMA with AAm increased the hardness value and glass transition temperature of PMMA denture base resins.