• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.15 no.4
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• pp.356-360
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• 2002

The piezoelectric properties of $0.05Pb(Al_{0.5}Nb_{0.5})O_3-0.95Pb(Zr_{0.52}Ti_{0.48})O_3+0.7wt%Nb_2O_5+o.5wt%MnO_2$ ceramics with the additive of BaCO$_3$were investigated. As the addition of BaCO$_3$increased from 0 to 0.4 wt%, the dielectric constant ($\epsilon^T _{33}$), piezoelectric constant ($d_33$), electromechanical coupling factor ($k_p$), and mechanical quality factor ($Q_m$) increased, while the dielectric loss ($tan\delta$) decreased. The highest piezoelectric and dielectric properties were observed at $1200^{\circ}C$ of the sintered temperature with 0.4 wt% of $BaCO_3$, and the properties of $d_33$, $k_p$, and $Q_m$ were 339 pC/N, 60% and 1754, respectively.

• Culinary science and hospitality research
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• v.13 no.4
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• pp.164-177
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• 2007

The purpose of this study is to explore the relationship between the service of employees in the foodservice industry and their customers' satisfaction. The study surveyed 310 subjects who are the employees of companies in Busan, Ulsan, City and Gyeongsangnam-do and processed the result using SPSS for Win V. 12. 0. For statistical analysis, Frequency, Factor Analysis and Regression were put into operation. As a result of Factor Analysis on the quality of company food-service, six factors have been extracted. The result of the Factor Analysis of satisfaction revealed one factor. In conclusion, this study shows that the quality of foodservice - food, convenience, menu, kindness, hygiene/cleanliness, facilities - had a positive effect on users' satisfaction. It is expected that the results will provide a base for marketing strategies to be used by the managers and marketers in foodservice companies.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.11a
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• pp.255-258
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• 2000

In this study, the structural, dielectric and piezoelectric properties of Pb[(Sb$\sub$1/2/Nb$\sub$1/2/)$\sub$x/- (Ni$\sub$1/3/Nb$\sub$2/3/)$\sub$0.15-x/- (Zr,Ti)$\sub$0.85/]O$_3$(x = 0, 0.01, 0.02, 0.03, 0.04, 0.05) ceramics is investigated as a function of Pb(Sb$\sub$1/2/Nb$\sub$1/2/)O$_3$ (abbreviated PSN) substitution. With the increase of PSN substitution, the crystal structure is transO$_3$formed from the tetragonal phase to the rhombohedral phase and the grain size is decreased abruptly. The curie temperature is decreased with the PSN substitution. The dielectric constant is increased with the PSN substitution and maximum value of 2290 is obtained at 4mol% PSN. With the PSN substitution, the coercive field is increased and the remnant polarization is decreased. The Electromechanical coupling factor(k$\sub$p/) Is showed the highest value of 0.622 at lmol% PSN and the mechanical quality factor(Q$\sub$m/) is decreased abruptly with the PSN substitution.

• Journal of Navigation and Port Research
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• v.35 no.4
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• pp.299-302
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• 2011

In this letter, the effect of quality factor on center frequency deviation in miniaturized coupled line bandpass filter (BPF) with diagonally end-shorted at their opposite sides and lumped capacitors is theoretically analyzed. The miniaturized BPF of a two-stage structure with two types of quality factors in standard CMOS process was designed and manufactured at 5.5 GHz. The die area of BPF was $1.44{\times}0.41\;mm^2$. The measured center frequency of BPF with a quality factor of 4.9 was deviated from 5.5 GHz to 4.7 GHz. The one with 14.8 was shifted to 5GHz. The theoretical and measured results validate that quality factor influences the center frequency shift of BPF.

• Journal of Sensor Science and Technology
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• v.13 no.2
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• pp.152-156
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• 2004

The dielectric and piezoelectric properties of 0.36Pb($Sc_{1/2}Nb_{1/2}$)$O_{3}$-0.25Pb($Ni_{1/3}Nb_{2/3}$)$O_{3}$-0.39Pb$TiO_{3}$ (hereafter PSNNT) at the morphotropic phase boundary (MPB) composition were investigated with $0{\sim}2.5$ mot% $MnO_{2}$ doping. Bulk density, dielectric loss and tetragonality of crystal structure were all improved with increasing $MnO_{2}$ additive content. With increasing $MnO_{2}$ additive content, the electromechanical coupling factor and quality factor were also increased: Electromechanical coupling $k_{p}$ and quality factor $Q_{m}$ at 2.0 mol% $MnO_{2}$ doping with were showed highest values of 55.6 % and 252, respectively.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1995.11a
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• pp.5.2-8
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• 1995

0.15($Ba_{1-x}Sr_{x}$)O-$0.15Sm_2O_3$-$0.7TiO_2$(x=0∼9[m/o]ceramics were fabricated by mixed-oxide method. Microwave dielectric properties were investigated with sintering conditions aid Sr addictive. In the specimen with x=0[m/o] sintered at 1350∼1470[$^{\circ}C$], dielectric constant, quality factor and temperature coefficient of resonant frequency were 70∼74, 2800∼3300(at 3[GHz]), -1.33∼+l.66[ppm/$^{\circ}C$, respectively. Increasing the Sr additive from 0 to 5[m/o], dielectric constant and temperature coefficient of resonant frequency were increased and quality factor was decreased. In the specimen with x=r[m/o] sintered at 1375[$^{\circ}C$], 6[hr], dielectric constant, quality factor and temperature coefficient resonant frequency were 75.62, 2785(at 3[GHz]), +8.39[ppm/$^{\circ}C$], respectively.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.24 no.6
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• pp.147-153
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• 2010

When small scale wind and solar power generation systems are connected to conventional power distribution system. It is worried that it can affect the quality of electricity such as voltage variation, power factor, frequency, harmonics and flicker. Therefore, in this research, in order to investigate the effects of wind power generation equipments(AC link method) on electrical power quality, when they are connected to distribution system. Power quality analyzer was installed respectively at the front side of power conversion system of conventional wind generation system and secondary side of consumer's power supply at distribution line. Measurements on power quality were performed and the effects of the wind generation system on distribution system were analyzed when it was and was not operated. The results show that 0.34[%] increase on voltage variation, 0.145 increase on current crest factor and 0.6[$^{\circ}$] deviation on phase difference when the power generation system was operated.

• Analytical Science and Technology
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• v.19 no.6
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• pp.544-552
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• 2006

Emission tests were carried out to investigate the characteristics of concentration according to flooring sort using small chamber method. The target Volatile Organic Compounds (VOC) included 27 individual compounds of environmental concern, which were determined by adsorption sampling and thermal desorption coupled with GC/MS method and by DNPH cartridge/HPLC method. The emission factor of Total Volatile Organic Compounds (TVOC) and Formaldehyde (HCHO) was detected $0.3mg/m^2{\cdot}h$ and $0.2mg/m^2{\cdot}h$ respectively, and the floorings of 37 (9 PVC Tile, 10 PVC Sheet, 18 Flooring) were satisfied emission standard. TVOC emission factor appeared in order of concentration of PVC Sheet, PVC Tile, and floor flooring, while HCHO was detected very high emission factor (as $0.4mg/m^2{\cdot}h$) at floor flooring above PVC series (as $0.001mg/m^2{\cdot}h$).

• Korean Journal of Hospice Care
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• v.6 no.2
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• pp.69-78
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• 2006

Purpose: This study was conducted to analysis relationship about quality of life and family burden of the home-based hospice patient families. Method: The subjects consisted of 94 families with home-based hospice patient. The ages of the subjects were 17-73 years with hospice patient who receivedhome visiting care and registered at 4 hospitals in Daegu and Kyung-Buk. The data was collected from March to November 2004. The instruments used for the study were Quality of Life Scale (GLS) and Family Burden Questionnaire (FBQ). The analysis was done using frequency, mean, standard deviation, correlation and stepwise multiple regression with SPSS WIN 11.0. Results: The results were as follows: 1. The mean score of family burden was 3.36 ($\pm0.55$). The highest mean score of family burden 6 factors were wellness of future 3.85($\pm1.10$), and the second was economic family burden 3.63($\pm0.97$). 2. The mean score of quality of life was 3.09 ($\pm0.48$). The lowest score of quality of life 6 factors were economic status 2.86($\pm0.54$), and the second was physical state and function 3.01($\pm0.62$). 3. In the home-based hospice patient families, family burden had significant negative correlation with quality of life(r=-0.25, p=0.012). 4. Emotional status accounted for 11% of family burden in the home-based hospice patient families by means of stepwise multiple regression. 5. Economical status accounted for 18 and age accounted for an additional 11% of quality of life in the home-based hospice patient families by means of stepwise multiple regression. Conclusion: The finding showed that family burden and quality of life of home-based hospice patient families were significantly negative correlation and the highest factor of family burden was wellness of future and the most important factor of quality of life was economic status.

• Journal of Korean society of Dental Hygiene
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• v.11 no.3
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• pp.383-393
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• 2011

Objectives : This study has been undertaken for the purpose of finding out what influence is made by the dental care service provided to patients by the dental clinics to the level of patient satisfaction to provide the base data for developing and improving the dental care service of dental hygienist. Methods : The survey was undertaken for 500 patients visiting 18 dental clinics in City G and the questionnaire was undertaken for two weeks in May 2010, and 473 copies were analyzed with the exception of the questionnaires with many omissions in the response. Results : 1. Distribution of the level of satisfaction for patient had the dentist factor which was highest in the dentist factor for 4.43 at the age of 60s (p<0.05). and in sole proprietorship for 4.49 (p<0.01). treatment procedure factor which was highest in sole proprietorship for 4.16 (p<0.001). environment of dental clinic factor which was highest at the age of 60 years or older for 4.36 (p<0.05) and in sole proprietorship for 4.14 (p<0.01). 2. Evaluation on the quality of the dental care service of dental hygienist had the kindness of dental hygienists which was highest at the age of 60 years or older for 4.40(p<0.001), knowledge factor of dental hygienist which was highest for 4.34 at the age of 60 years or older (p<0.05) and highest 4.27 for visit dentists(p<0.001) and the patient management and other factor was highest at the age of 60s for 4.47 (p<0.05), and in sole proprietorship for 4.28 (p<0.05). 3. Factors influencing on the level of satisfaction for patient. The level of satisfaction for patient was higher for higher evaluation of the dentist quality (p<0.001), for feeling convenient in treatment procedure and use (p<0.01), for feeling kindness of the dental hygienist (p<0.01), and for higher evaluation in patient management and other management activities of the dental hygienist (p<0.001). Conclusions : In order to heighten the level of satisfaction for patient, it would be necessary to strengthen the kindness and patient management aspect on the patients of the dental hygienist, and it would require to heighten the quality of dentist as patients recognize and heighten the treatment procedure and service convenience of dental clinics.