• KSBB Journal
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• v.25 no.1
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• pp.97-102
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• 2010

The enhancement of immunity for atopic dermatitis with application of eicosapentaenoic acid (EPA)-loaded liposome was evaluated on NC/Nga mice. The EPA-loaded liposome was coated with thiol-chitosan. The liposomes were characterized with transmission electron microscopy (TEM), surface zeta potential & particle size analyzer (Zeta-PSA) and differential scanning calorimetry (DSC). The loading efficiency of EPA in the liposome was about 4.7%. The particle size of the EPA-Ioaded liposome was about 230 nm. The values of Immunoglobulin E (IgE), interleukin-4 (IL-4), and tumor necrosis factor-$\alpha$ (TNF-$\alpha$) were reduced significantly with application of the EPA-loaded liposome. The interferon-$\gamma$ (IFN-$\gamma$) value was increased with the application effect. It is concluded that EPA loaded liposome have immunity advancing effects in mouse model of atopic dermatitis.

• Journal of Powder Materials
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• v.17 no.5
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• pp.404-408
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• 2010

The effects of high energy ball-milling (HEBM) on the sintering behavior and piezoelectric properties of 0.1 wt% $Li_2CO_3$ doped 0.8Pb($Mg_{1/3}Nb_{2/3}$)$O_3$-0.2Pb($Zr_{0.475}Ti_{0.525}$)$O_3$ (PMN-PZT) ceramics were investigated. It was found that HEBM treatment was quite effective to reduce the average particle size down to 300 nm, leading to increased density as well as enhanced piezoelectric properties of a sintered specimen even though prolonged HEBM resulted in unwanted secondary phases that caused a degradation of piezoelectric properties. The dielectric constant ($\varepsilon_r$), piezoelectric coupling factor ($k_p$) and piezoelectric constant $d_{33}$ of 0.1 wt% $Li_2CO_3$ doped PMN-PZT ceramics prepared via HEBM for 10 h reached 2040, 0.68 and 554 pC/N, respectively.

• Journal of Powder Materials
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• v.21 no.6
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• pp.441-446
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• 2014

In this study, we synthesize silica-core gold-satellite nanoparticles (SGNPs) for the surface-enhanced Raman scattering (SERS) based sensing applications. They consist of gold satellite nanoparticles (AuNPs) fixed on the silica core nanoparticles, which sizes of AuNPs can be tunned by varying the amount of reactants (growth solution and reducing agent). Their surface plasmon resonance (SPR) properties were characterized by using UV-vis spectroscopy, showing that the growth of AuNPs on silica cores leads to the light absorption in the longer wavelength region. Furthermore, the size increase of AuNPs exhibited the dramatic change in SERS activity due to the formation of hot spots. The optimized SGNPs showing enhancement factor ${\sim}3.8{\times}10^6$ exhibited a detection limit of rhodamine 6G (R6G) as low as $10^{-8}M$. These findings suggest the importance of size control of SGNPs and their SPR properties to develop highly efficient SERS sensors.

• Composites Research
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• v.12 no.1
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• pp.19-27
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• 1999

A design development test for carbon/epoxy composite laminates for an aircraft flight control system is performed. The design development test includes moisture absorbing test, tensile, compressive, bearing and lap shear tests. The moisture absorbing behavior for different fiber orientation angles is investigated and the changes in mechanical characteristics are compared. In the in-plane tensile test, the effect of damages such as scratches and impacts is studied. The bearing test is performed for different fastening types. The resulting design allowable stress and environmental load enhancement factor are used for the structural analysis and certification tests for the flight control system.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.7 no.1
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• pp.97-109
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• 2004

The disposal of stormwater is one of the major problems in urban water management. One method of reducing peak runoff rates and other detrimental impacts of stormwater is detention storage. Detention ponds as a water quality control alternatives have been investigated by a number of researchers. Recognizing multiple roles such as flood peak attenuation, pollution removal and aesthetic enhancement, the design and management of detentions ponds deserve more research. The purpose of this research is to establish design criteria wet detention ponds to improve water quality. Water quality in detention pond discharge might be improve with physical, chemical and biological alterations. Physical alteration was focused in this study. There are several methods for estimating the suspended solid control capability of wet detention ponds. Existing models of suspended solids removal are based on sedimentation and gravity settling theory. The pollutant trap efficiency of pond is a function of several interrelating factors. Detention time is the most important factor, because it determine gravity settling quantities of pollutants. Desirable modification of physical factors for improvement of water quality in wet detention ponds are volume ratio, area ratio, length to width ratio, depth, out let location, bottom soil type. In order to apply design procedure in actual site, Namak new town development area was selected.

• Transactions of Materials Processing
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• v.17 no.3
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• pp.182-188
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• 2008

Crash box is one of the most important automotive parts for crash energy absorption and is equipped at the front end of the front side member. The specific characteristics of aluminum alloys offer the possibility to design cost-effective lightweight structures with high stiffness and excellent crash energy absorption potential. This study deals with crashworthiness of aluminum crash box for an auto-body with the various types of cross section. For aluminum alloys, A17003-T7 and A17003-T5, the dynamic tensile test was carried out to apply for crash analysis at the range of strain from 0.003/sec to 200/sec. The crash analysis and the crash test were carried out for three cross sections of rectangle, hexagon and octagon. The analysis results show that the octagon cross section shape with A17003-T5 has higher crashworthiness than other cross section shapes. The effect of rib shapes in the cross section is important factor in crash analysis. Finally, new configuration of crash box with high crash energy absorption was suggested.

• The Korean Journal of Health Service Management
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• v.7 no.4
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• pp.65-79
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• 2013

The purpose of this study was to reveal relationship between positive illusions and oral health promotion behaviors. Positive illusions was composed of positive self-perception, exaggerated sense of personal control, and unrealistic optimism. We thought these factors affect to the oral health behaviors. For this study, 307 collegians in Ulsan, Yangsan are participated in this study. The data was subjected to confirmatory factor analysis and structural equation modeling with SPSS 18.0, AMOS 18.0. In conclusion, we obtained the next results. First, positive illusions has a statistically significant with oral health promotion in correlation analysis(p<0.05). Second, Structural equation modeling fit index was well fitted as $X^2$=100, df=112, P=0.893, RMR=0.021, GFI=0.969, AGFI=0.943. Only positive self-perception and exaggerated sense of control has a statistically significant(P<0.05). Third, the group of the highest positive illusions has a statistically significant in all factors(P<0.05), the other hand, the group of the lowest positive illusions has not statistically significant in all factors(P>0.05). So, as this results we concluded that the self-confident or activated persons were very well performed in oral health promotion behaviors.

• Journal of the Korean Society of Clothing and Textiles
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• v.30 no.1 s.149
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• pp.31-37
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• 2006

The purpose of this study was to value the present condition of natlwal dyeing, to forecast needs in natural dyeing world and to off the preliminary data on future direction of research and enhancement plan. The three-round Delphi tests were performed with 36 professional in the academic, the industrial, and the art world. The result of the study is as follows: Factor analysis showed the troubles were classified into 4 categories; 'dyeing', 'basis', 'industry' and 'consumer and environment'. Supplementary measures and future direction research 3categories; 'development', 'education' and 'mass production' And commercialization. popularization 2 categories; 'commercialization' and 'popularization'. 'Dyeing' is correlated with 'mass production', 'basis' with 'education' and 'education' with 'commercialization' and 'popularization'. The engaged period in natural dyeing world is longer, professionals were more concerned about 'consumer and environment' The most influential element of the present question in the view is 'education'.

• Journal of Korean society of Dental Hygiene
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• v.14 no.4
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• pp.555-561
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• 2014

Objectives : The aim of this study was to investigate the factors related to stress perception. Methods : A self-reported questionnaire was filled out by 109 people living in Gimpo city from January 16 to April 15, 2013. The data were analyzed using SPSS window ver. 19.0(IBM CO., Armonk, NY, USA) for t-test, one-way ANOVA, and multiple linear regression analysis. Results : Men and group of 59 years old tended to have higher stress perception than women and those who over 60 years old, but the results were not statistically significant. Stress perception was higher among the group with systemic dryness and oral dryness(each${\geq}1$) and the group reporting high difficulty in daily living due to oral problem(${\geq}2$)(p<0.05). Especially, the factor that was most correlated to stress perception was systemic dryness(${\beta}$=0.347) followed by problem of daily living for oral problem(${\beta}$=0.278, p<0.01). Conclusions : Systemic dryness and oral problem can increase the level of stress perception, mouth dryness and oral problems are a part of stress responses. Therefore, the regular health checkup must be done and early treatment to reduce stress perception as well as negative aspects caused by stress. It will contribute to the enhancement of public health and life of quality.

• Transactions of the Korean Society of Automotive Engineers
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• v.5 no.6
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• pp.64-76
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• 1997

This paper deals with development of brackets by using aluminum alloy sheets which is indispensable for weight reduction of autobody. The press formability of aluminum alloy sheet is estimated by means of tensile test, V bending test, sample manufacturing test and photograph of microstructure. The results show that the elongation, strength, work hardening exponent, plastic anisotropy coefficient of Al 6***series are better than those of Al 5***series, but for general press formability, Al 5***series are better than Al 6***series due to lower yield strength. Since most of mechanical properties of aluminum sheet are generally inferior to those of cold-rolled steel sheet, shape fixability and press formability of aluminum sheet are very poor. For making components of autobody by use of die for steel sheet application, it is essential that die should be nodified for least bending and stretching. With the modified die for aluminum, it could be possible to make brackets, the component of autobody. Microstructure of Al 5***series has fine grain and small the 2nd phase and that of Al 6***series has relatively coarse grain. Therefore, it seems that fine grain and small the 2nd phase of Al 5***series is one of the factor of lower yield strength, resistance to stamping work, formation of Luder's line.