• Korean Journal of Environmental Agriculture
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• v.27 no.1
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• pp.1-9
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• 2008

The main purpose of this study is to accumulate the fundamental data representing groundwater of plastic film houses by means of water quality and its multivariate statistical analysis. Groundwater samples were collected in every two years since 2000 to 2004 from total 211 sites. According to the result of water quality analysis, ground water quality was suitable for irrigation purpose averagely. Correlation analysis showed that EC was highest positively correlated with $Mg^{2+}$ to 0.810(p<0.01), 0.776(p<0.01) in April and July, respectively. $NO_3-N$ was highest positively correlated with T-N to 0.794(p<0.01) in October. This result shows that it can lead to a different result even in similar case sometimes. Four factors were extracted through factor analysis in April and July, but five factors were extracted in October. The proportions of cumulative variance by the factor were 64.9, 60.2, and 70.7 in April, July, and October, respectively. The first factor was highly related to anions and cations such as $Ca^{2+},\;Mg^{2+},\;Cl^-,\;{SO_4}^{2-}$, and EC in contrast to that of stream water. According to the cluster analysis, 211 sites are classified into four groups. Common type of ground water quality was shown in group A. The pH and $PO_4-P$ were highest in Group B. The anions and cations were highest in Group C. $COD_{Cr}$ was highest in Group D.

• Journal of Korean Society on Water Environment
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• v.36 no.5
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• pp.431-444
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• 2020

The relationship between dam construction and water quality has recently come to be considered an important issue. A dam is a physical factor which causes changes to the river system around it. Considering these points, this study was conducted to obtain basic data by analyzing the relationship between water level fluctuations and water quality parameters in the short-term. In terms of methodology, the new construction of the Yeongju Dam (M5) in 2016 was divided into Stage 1 as the lotic system and Stage 2 as the lentic system, with four years in each period, and the water level fluctuations and water quality were analyzed using official data. As a result of this study, M5, a stagnant area in which organic matter and nutrients accumulate, was found to be an important factor in water quality management. In addition, the water level changed rapidly (0.9±0.2 m → 10.9±7.1 m) as the river environment condition was converted from the lotic system to the lentic system. In addition, water quality parameters such as BOD, COD, TOC, and Chl-a significantly changed in the short-term. Further, since the transport of organic matter and nutrients occurred well in the lotic system, sedimentation was expected to be dominant in the lentic system. Therefore, it was determined that when the river flow is blocked, autochthonous organic matter is an important factor for long-term water quality management in the future. This process can increase the trophic state of the water body. As a result of this study, the TSI_KO value was converted from mesotrophic in Stage 1 to eutrophic in Stage 2. Eventually, short-term changes in the river environment will affect not only changes in water level but also changes in water quality. Thus, a comprehensive and strategic approach is needed for long-term water quality management in the future.

• The Journal of Korean Society for Radiation Therapy
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• v.14 no.1
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• pp.187-199
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• 2002

This descriptive study was undertaken to measure quality of life score and investigate the correlation between the demographic characteristics, the diagnostic related characteristics, physical symptom and quality of life of breast cancer patients undergoing radiation therapy as on attempt to provide basic data to help them attain better qualify of life. The subjects for this study were 74 out-patients undergoing radiation therapy at C University hospital in Gwangju, from June, 1998 to July, 2000. The data were obtained using a convenient sampling technique. The tool of this study was the quality of life scale developed by Ro Yoo Ja. The data were analyzed using the SAS program for percentage, mean, standard deviation, Pearson Correlation Coefficient, GLM. The results were as follows: 1. The total average score for quality of life of the subjects was 137.22 and the range was from 38 to 227, item mean score(range 1-5) was 3.15. For each factor in qualify of life of life score, the mean scores(range 1-5) were as follows; family relationship 3.69, relationship with neighbors factor 3.40, self esteem 3.10, physical state and function 2.95, economic life 2.91, emotional fate 2.88. 2. The incidence of physical symptoms was seen fatigue($82.4\%$), skin change($43.2\%$), alopecia($41.9\%$), pain($41.9\%$), anorexia($39.2\%$), anemia($39.2\%$), and headache($31.1\%$) in that order. 3. The result of the analysis of the relationships between the quality of life scores and demogaphic characteristics were as follows : there were significant differences, between age(F=3.44, p=0.013), educational level(F=3.84, p=0.007), duration of marriage((F=5.06, p=0.003) and monthly income(F=4.72, p=0.005). 4. The result of the analysis of the relationships between quality of life scores and diagnostic related characteristics was as follows: there was a significant difference between incidence durations(F=5.02, p=0.003). 5. The correlation of emotional state, economic life, self esteem, physical sate & function, relationship with neighbors, relationship with family in quality of life of cancer patients revealed a positive correlation.

• Journal of Distribution Science
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• v.13 no.5
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• pp.113-120
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• 2015

Purpose - As the rapid development of ICT has been made recently, many domestic companies are trying to introduce smart work infrastructure. The purpose of institution of smart work is to enhance their performance. To this end, it is necessary to advance the way of working. Developing employees' collective intelligence should be regarded as a prerequisite for advancing the way of working. Job satisfaction of the employees is another important factor to enhance organizational performance. So this study aims to provide the theoretical background of systematic approach to smart work quality by empirically analyzing the effect of smart work quality on collective intelligence and job satisfaction. Research design, data, and methodology - A structural equation model was designed to examine cause-and-effect relationships among three latent variables(smart work quality, collective intelligence, job satisfaction). Three hypotheses were formulated. The first hypothesis is that the effect of smart work quality on collective intelligence will be positively and statistically significant. Likewise, the second hypothesis is that the effect of smart work quality on job satisfaction will be positively and statistically significant. Finally, the third hypothesis is that the effect of collective intelligence on job satisfaction will be positively and statistically significant. Based on the previous researches, 34 questionnaire items were developed to measure the effect of the three variables. The survey was conducted on 162 employees who are working under smart work environment. The number of the effective questionnaires for the analysis was 154. PASW Statistics 18 and AMOS 18 were used for the statistical analysis. Results - The validity and reliability test for questionnaire items have been carried out. From the factor analysis, 1 out of 34 items was eliminated. As a result, 33 out of 34 items were used for analyzing. The values of Cronbach's α ranged from 0.701 to 0.910, indicating the acceptable reliability of the questionnaire items. The values of χ2, df, CFI, TLI, RMSEA of the model are 102.838, 51, 0.949, 0.935, 0.082, respectively. So the structural equation model was statistically significant. The first and third hypotheses were supported. But the second hypothesis was rejected. Conclusions - An analysis using structural equation model showed meaningful implications about the effect of smart work quality on collective intelligence and job satisfaction. First, as the five quality elements of the smart work improved, the level of collective intelligence increased. Second, the statistical analysis showed smart work didn't have a direct effect on job satisfaction, which is inconsistent with the prior findings. The main purpose of smart work is to help achieve greater performance. The companies also need to make efforts to improve job satisfaction of their employees along with achieving greater performance. Third, an organization with higher level of collective intelligence showed greater job satisfaction. The companies under smart work environment need to develop functions to encourage participation, sharing, openness, and collaboration. This research will provide useful information for the companies which want to introduce smart work, distribution information system, management information system, etc.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.49 no.3
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• pp.155-160
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• 2000

The piezoelectric properties and the doping effect for$0.95Pb(Zr_xTi_{1-x})O_3+0.05Pb(Mn1/3Nb2/3)O_3$ compositions were studied. Also, the heat generation and the change of electromechanical characteristics, the important problem in practical usage, were investigated under high electric field driving. As a experiment results under low electric field, the values of kp and $\varepsilon33T$ were maximized, but Qm was minimized(Kp=0.57, Qm=1550) in the composition of x=0.51. In order to increase the values of Qm $Nb_2O_5$ was used as a dopant. As the result of that, the grain size was suppressed and the uniformity of grain was improved. Also, the values of kp decreased, and the values of Qm increased with doping concentration of $Nb_2O_5$. As a experiment results under high electric field driving, when vibration velocity was lower than 0.6[m/s], the temperature increase was $20[^{\circ}C]$, and the change ratio of mechanical quality factor was less than 10[%]. So, its electromechanical characteristics was very stable. Conclusively, piezoelectric ceramic composition investigated at this paper is suitable for application to high power piezoelectric devices.

• Journal of Oral Medicine and Pain
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• v.40 no.4
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• pp.140-145
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• 2015

Purpose: Bruxism is commonly considered a major risk factor for temporomandibular disorders (TMD), and the psychosocial factors had been one of the etiologic factor of bruxism. But there are still unsolved issues on the relationship between sleep bruxism and TMD and the etiologic factors of bruxism. This study is aim to evaluate the clinical and psychosocial characteristics according to diagnostic grade of bruxism in TMD patients. Methods: Three hundred subjects were enrolled who were under the stabilization splint therapy for TMD. Recently international consensus proposed a diagnostic grading system of "possible", "probable", and "definite" sleep or awake bruxism for clinical and research purpose. According to their suggestion, we classified these subjects as self-reported bruxism (SRB) and wear facet bruxism (WFB). We investigated the clinical characteristics (sex, age, chief complaint, pain duration, visual analogue scale), sum of tenderness (temporomandibular joint, masticatory muscles, cervical muscles), diagnosis of TMD according to research diagnostic criteria (the Research Diagnostic Criteria for Temporomandibular Disorders, RDC/TMD), headache, subjective sleep quality (Pittsburgh Sleep Quality Index, PSQI), and psychosocial characteristics (Symptom Checklist-90-Revised, SCL-90-R) in enrolled subjects. We compared the clinical and psychosocial characteristics between these bruxism groups. Results: There were no significant correlation between self-reported and WFB (p=0.13). SRB subjects more reported pain as a chief complain than subject who did not report bruxism (p=0.014). The mean score of global PSQI was significantly higher in SRB than in did not report positively subjects (p=0.045). The mean score of anxiety and phobic anxiety was significantly higher in SRB than in did not reported positively subjects (p=0.045, p=0.041). Conclusions: Although bruxism is regarded as risk factor of TMD, this study showed inconsistent result between SRB and clinically detected bruxism by wear facet on slpint. We suggest that the clinician should consider with extreme caution when they assess SRB.

• International Journal of Contents
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• v.16 no.3
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• pp.45-50
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• 2020

Occupational therapists (OTs) interface patients much longer than other healthcare workers and, thus, are likely to experience a high level of stress because of work, physical fatigue, lack of professional knowledge and skills, and problematic relationships with patients, etc. This study examined the quality of the lives of OTs and the workplace which is an influential factor. This study recruited 200 OTs and used a professional quality of life scale. We found that, only 27.0% experience high levels of compassion satisfaction (CS) and 80.5% and 74.5% experience high or average levels of burnout (BO) and secondary traumatic stress (STS) of compassion fatigue (CF), respectively. We discovered that CS was higher in temporary employees; and CF was higher in females, subjects in their 30s; and those working at general hospitals. Also, BO was higher in those with one to five years of clinical experience and regular employees. Last, STS was higher in the group without stable income. This study verified that clinical experience is a critical factor that reduces BO, and excessive workload outside of treatment lowers the professional quality of life. This suggests that work environment and regulations related to OTs must be improved to increase CS and reduce CF.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.15 no.9
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• pp.788-793
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• 2002

The glass-electroceramics were composed of glass composition(CaO, $SiO_2$, $B_2$ $O_3$) and electroceramic composition(BaO, N $d_2$ $O_3$, B $i_2$ $O_3$ and Ti $O_2$) Their dielectric properties have been investigated as a function of sintering temperature and glass contents. In the ceramics composed of 0.16BaO-0.15(N $d_{0.87}$,B $i_{0.13}$)$_2$ $O_3$-0.69Ti $O_2$with glass ［EG-2782］ 3wt% addition and sintered at 108$0^{\circ}C$ for 2h, we could obtain microwave properties of dielectric constant $\varepsilon$$_{r}$ = 80.1, quality factor Q $\times$f = 810(at 3.5 GHz) and temperature coefficient of resonant frequency $\tau$$_{f}$ = -1.3 ［ppm/$^{\circ}C$］. These experimental results show that dielectric constant and temperature coefficient of resonant frequency could be estimated by empirical equations involving the rule of mixture.e.

• The Korean Journal of Ceramics
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• v.6 no.4
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• pp.348-353
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• 2000

The effects of MnO$_2$ and Fe$_2$O$_3$ on the piezoelectric properties of 0.05PMN-0.451PT-0.499PZ ceramics were investigated. The addition of MnO$_2$ increased mechanical quality factor (Q$_m$) but decreased the dielectric constant (K$^{T}_{33}$) and compliance (S$^{E}_{11}$) of the specimens. These results indicated that MnO$_2$ behaves as an acceptor in 0.05MN-0.451PT-0.499PZ ceramics. The electromecanical coupling coefficient (K$_P$) of 0.05PMN-0.451PT-0.499PZ ceramics slightly increased with the addition of MnO$_2$ however, the enhancement of $K_P$ was insignificant. A small amount of Fe$_2$O$_3$ was added to enhance the $K_P$ of the 0.05PMN-0.451PT-0.499PZ + 0.5 wt% MnO$_2$ ceramics. The addition of Fe$_2$O$_3$ largely increased $K_P$ through the increase of the K$^{T}_{33}$ and the polarization. The mechanical quality factor of the specimens decreased with the addition of Fe$_2$O$_3$however, the reduction was negligible.

• Culinary science and hospitality research
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• v.15 no.4
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• pp.227-244
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• 2009

This study was conducted to develop a multiple-item scale for measuring the food service quality in the restaurant industry. For developing the scale, Kelly Repertory Grid Methods were conducted. Collected data of food service quality were analyzed with the reliability analysis and the factor analysis of SPSS 12.0 and the 3rd-order confirmatory factor analysis of LISREL 8.70. The food service quality model of this study is conceptually based on the Brady and Cronin(2001)'s hierarchical approach to the service quality model. The hierarchical model of the food service quality which comprises three constructs of the physical environment quality, the interaction quality and the food quality as a primary dimension. The hierarchical approaches to the food service quality help overcome the limitations of the SERVQUAL model for which some arguments have been made that it lacks a clear division between the dimensions and its subsequent overlapping between them.