• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.21 no.7
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• pp.645-651
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• 2008

To reduce noise in high frequency and distortion of signal, the composition of $(Ca_{0.7}Sr_{0.3})(Zr_{0.97}Ti_{0.03})O_3$ and $(Ba_{0.2}Ca_{0.4}Sr_{0.4})TiO_3$ was developed. The composition was not solid solution, but mixtures of various phases composed of Ca, Sr, Zr, Ti and Ba oxides. The dielectric constant increased, the quality factor and the insulation resistance decreased with $(Ba_{0.2}Ca_{0.4}Sr_{0.4})TiO_3$ content. The composition of $0.4(Ba_{0.2}Ca_{0.4}Sr_{0.4})TiO_3$ satisfied the electric characteristics and the temperature coefficient of dielectric constant (TCC). In addition, the glass frit and $MnO_2$ also affected the electric characteristics. From the result of the best fit simulation, $MnO_2$ 0.3 mol%, the glass frit 0.6 wt% showed the insulation resistance $906{\Omega}{\cdot}F$, the quality factor 821, and the dielectric constant 92. With the selected composition, MLCC capacitors sized $4.5{\times}3.2{\times}2.5mm$ were manufactured with 105 layered of the dielectric thickness $16{\mu}m$ using Ni inner electrode, They represented the capacitance $98{\sim}102$ nF, the quality factor 1,200 and the insulation resistance $1,500{\Omega}{\cdot}F$. Also, they had high break-down voltage with $107{\sim}115V/{\mu}m$, and satisfied the SL TCC characteristics.

• Korean Journal of Adult Nursing
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• v.14 no.3
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• pp.401-410
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• 2002

Purpose: This research was designed to develop an instrument that can be used for measuring of the quality of life for the elderly in Korea. Method: Subjects were 2,110 aged people, residing in Seoul and Kyeungi-Do. In developing this instrument, the researcher first established a conceptual framework based on the literature review and interview and open questionnaire. The collected data were analyzed using the SPSS-WIN program. For the component factors of the measuring instrument, a factor analysis method and item analysis was used. The reliability of the scale was tested by Cronbach's alpha. Result: 1) The results of the analysis of the 32 items making up the instrument were classified into the following 4 factors: life stability, easy of resource utility, health and affection in family, establishment of supportbase. 2) The reliability of the instrument for the quality of life was 0.952 (Cronbach's alpha). In the factor analysis Cronbach's alpha correlations for the 4 factors ranged from 0.736 to 0.949. Conclusion: This scale could be adequately applied in assessing the quality of life for the elderly in Korea. And the results of this scale in a study can contribute to the promotion of quality of life for the elderly.

• Journal of the East Asian Society of Dietary Life
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• v.23 no.6
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• pp.850-861
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• 2013

This study aimed at investigating any differences perceived between the contractor and the contractee based on an importance-performance analysis (IPA) of foodservice quality attributes. Questionnaires were distributed to 200 personnel concerned in the Busan, Ulsan and Kyungnam areas and a total of 134 valid responses were used for analysis. Of the 23 foodservice quality attributes, the factors of 'food quality', 'employee service', 'hygiene and safety', 'customer orientation' and 'operation quality' were induced from a scale purification process through the exploratory factor analysis. The level of importance (p<0.01) of the 'hygiene and safety' factor and 'employee service' factor was not found to be significantly different between the groups. In the level of performance, the factors of 'food service', 'employee service', 'customer orientation' and 'operation quality' were found to be perceived significantly lower than expected by the contractor group. In the importance level, 'food quality', 'employee service', 'hygiene and safety', 'customer orientation' and 'operation quality' were rated by the contractor as 4.03, 4.30, 4.27, 4.01 and 4.12 points, respectively. In contrast, in the performance level, perceived 'food quality', 'employee service', 'hygiene and safety', 'customer orientation' and 'operation quality' were evaluated as 3.57, 3.94, 4.06, 3.83 and 3.95 points, respectively.

• The Korean Journal of Food And Nutrition
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• v.27 no.1
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• pp.128-135
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• 2014

The purpose of this study is to analyze the gap in perceived importance-satisfaction rates of foreign Chinese students regarding the university foodservice selection attributes. All statistical analyses are conducted by the SPSS package program (ver 20.0). The results of the statistical analyses are as follows: The validity of the 22 food service selection attributes is being evaluated via the exploratory factor analysis and then five factors are extracted. The five factors are: 'Factor 1. Cleanness and service quality', 'Factor 2. Food quality and price', 'Factor 3. Physical environment', 'Factor 4. Convenience', and 'Factor 5. Service environment'. According to the results of one-way ANOVA, physical environment showed that significant differences across the periods of residence in Korea and the eating frequency at on campus foodservices. On the other hand, the food quality and price, convenience, and service environment showed that significant differences across the periods of residence in Korea. In addition, according to the Importance-Satisfaction Analysis results, 'ventilation of dining room' is the key aspect that university food service managers should reinforce. In conclusion, in order to increase the customer satisfaction rates, the food service managers should not only improve the quality of food and service but also the physical environments of the food service facility.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1999.11a
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• pp.232-235
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• 1999

In this paper, We described the effect of $MoO_3$ Addition and firing temperature on the microwave dielectric properties of $BiNb0_4$ ceramics. The specimens prepared by conventional mixed method was addicted by 0 - 0.03 wt% $MoO_3$ and fired at 860 - $950^{\circ}$ for 3hr. Density increased when $MoO_3$ is below O.Olwt% but decreased when over O.Olwt%. $BiNb0_4$ ceramics addicted with CuO 0.03wt % and $MoO_3$ 0.01 wt% showed microwave dielectric properties, Dielectric constant 37.5, Quality factor[Qx$f_0$]5500, Temperature coefficient of resonance frequency 15ppm/$^{\circ}$

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.49 no.5
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• pp.294-298
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• 2000

The $MgTiO_3\; and \;$0.9MgTiO_3-0.1SrTiO_3$ ceramics were fabricated by the conventional mixed-oxide method. The sintering temperature and time were $1300^{\circ}C~1600^{\circ}C$, 2hr., respectively. The structural and microwave dielectric properties were investigated with sintering temperature and the application for the satellite communication microwave dielectric resonator was investigated. The coexistence of cubic $SrTiO_3$ and hexagonal TEX>$MgTiO_3$ structures in $0.9MgTiO_3-0.1SrTiO_3$ ceramics were found from X-ray diffraction patterns. In the case of $MgTiO_3$ ceramics, sphere phase and needle-like phase were coexisted. The $0.9MgTiO_3-0.1SrTiO_3$ ceramics observed sphere phase. The dielectric constants and temperature coefficient of resonant $frequency(\tauf)$ were increased with addition of $SrTiO_3$ but the quality factor was decreased. The dielectric constant, quality factor and $\tau$f of the;$0.9MgTiO_3-0.1SrTiO_3$ ceramics were 22.61, 10.928(at 1GHz) and $+50.26ppm/^{\circ}C$, respectively.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.31 no.4
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• pp.212-215
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• 2018

The phase evolution, microstructure, and microwave dielectric properties of $Ba(Mg_{0.5-2x}Y_{2x}W_{0.5-x}Ti_x)O_3$ (x = 0.005~0.05) ceramics sintered at $1,700^{\circ}C$ for 1h were investigated. All compositions exhibited a 1:1 ordered cubic perovskite structure. The field emission scanning electron microscopy image revealed a dense microstructure in all the compositions. As the value of x increased, the lattice parameter, dielectric constant, and quality factor increased. The temperature coefficient of resonant frequency changed from $-19.6ppm/^{\circ}C$ to $-5.9ppm/^{\circ}C$ with increasing x value. The dielectric constant, quality factor, and temperature coefficient of resonant frequency of $Ba(Mg_{0.40}Y_{0.10}W_{0.45}Ti_{0.05})O_3$ were 21.7, 132,685 GHz, and $-5.9ppm/^{\circ}C$, respectively.

• The Journal of Korean Society for Radiation Therapy
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• v.14 no.1
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• pp.155-164
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• 2002

This descriptive correlation study was undertaken in order to investigate the relationship of family support and personality with quality of life in patients receiving radiotherapy for breast cancer and to provide basic data to help them improve a better quality of life. This subjects for this study were 74 out-patients undergoing a radiation therapy at C hospital in Kwang-Ju. The data were obtained using a convenience sampling technique. The tool of this study were Ro's qualify of life scale, Kang's family support scale and Wallston & others health locus of control scale. The data were analyzed using a SAS program for percentage, mean, standard deviation, Pearson Correlation Coefficient, GLM. The results were as fellows: 1. The total average score of the quality of life of the subjects was 137.22 (minimum score 38-maximum score 227), item mean score(range 1-5) was 3.15. The total average score of the family support of the subjects was 40.38(minimum score 21-maximum score 47), item mean score(range 1-5) was 3.69. The total average score of health locus of control of the subjects was 42.47(minimum score 28-maximum score 59), item mean score(range 1-6 was 3.69. 2. The results of the analysis of the relationship between the quality of life scores and the health locus of control were as follows : the total average score of the qualify of life of internal locus of control scale was 133.50, he total average score of the quality of life of external locus of control scale was 138.41. 3. There was positive correlation between the health locus of control and the quality of life(r=0.0722, p=0.5413). 4. There were significant positive correlation between family support and quality of life(r=0.2328, p=0.0399). The results of the analysis of the relationship between the each factor in the quality of life scores and family support were as fellows : There were significant difference between the self esteem factor(r=0.2974, p=0.0124), relationship with family factor(r=0.2657, p=0.0241)

• Journal of the Microelectronics and Packaging Society
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• v.8 no.1
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• pp.27-32
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• 2001

The effect of $V_2O_5$, a donor-type dopant on the degradation of quality factor of ($Zr_{0.8}, Sn_{0.2})TiO_4$was compared with Ta$_2$O$_{5}$ doped ($Zr_{0.8}, Sn_{0.2})TiO_4$ in terms of microstructure, electrical conductivity, and oxidation state of the dopant. It is well known that the addition of the donor type species such as $Ta_2O_5,Nb_2O_5, Sb_2O_5, WO_{3}$, increases the quality factor of ($Zr_{0.8}, Sn_{0.2})TiO_4$due to decrease the oxygen vacancy concentration. Unlike other dopants, however, the addition of $V_2O_5$ decreased the quality factor. The degradation of quality factor of ($Zr_{0.8}, Sn_{0.2})TiO_4$was resulted from the formation of grain boundary phase and $V_2O_5$rich fiber shaped secondary phase, and the increasing the oxygen vacancy concentration due to unstability of oxidation state of vanadium ions in ($Zr_{0.8}, Sn_{0.2})TiO_4$ceramic.c.

• Journal of the Korean Ceramic Society
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• v.32 no.3
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• pp.378-384
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• 1995

Effects of $La_2O_3$, $MnO_2$ on the dielectric and piezoelectric properties of $0.02Pb(Y_{2/3}W_{1/3}O_3-0.98Pb(Zr_{0.52}Ti_{0.48})O_3$ system were investigated. The addition of La2O3 to the system enhanced electromechanical coupling factor (kp), piezoelectric constant (d33), but hardly changed mechanical quality factor (Qm). On the other hand, the addition of $MnO_2$ increased Qm significantly, but did not degrade kp and d33 so much. The piezoelectric properties of $0.02Pb(Y_{2/3}W_{1/3}O_3-0.98Pb(Zr_{0.52}Ti_{0.48})O_3$ containing 0.1wt% $La_2O_3$, 0.4wt% $MnO_2$ were very good and kp, d33, Qm were 55%, 350$\times$10-12C/N, 780, respectively. The size of the grains was proportional to the change of c/a (tetragonality) ratio caused by the addition of $La_2O_3$ and $MnO_2$, and dielectric, piezoelectric properties were sensitive to the amountof pyrochrole phase.