• Journal of Periodontal and Implant Science
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• v.36 no.3
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• pp.613-625
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• 2006

Periodontal ligament(PDL) cells and human gingival fibroblasts(HGFs) play important roles in development, regeneration, normal function, and pathologic alteration. PDL cells and HGFs have the similarity related with general characteristics of fibroblast such as spindle shaped morphology, the presence of vimentin intermediate filament and the synthesis of interstitial collagens and fibronectin. There were many studies about the differences between PDL cells and HGFs, but they were not about whole gene level. In this study, we tried to explain the differences of gene expression profiles between PDL cells and HGFs, and the differences among three individuals by screening gene expression patterns of PDL cells and HGFs, using cDNA microarray. Although there were some variants among three experiments, a set of genes were consistentely and differentially expressed in one cell type. Among 3,063 genes, 49 genes were more highly expressed in PDL cells and 12 genes were more highly expressed in HGFs. The genes related with cell structure and motility were expressed more highly in PDL cells. These are cofilin 1, proteoglycan 1 secretory granule, collagen type I(${\alpha}$ 1), adducin gamma subunit, collagen type III(${\alpha}$ 1), fibronectin, lumican(keratan sulfate proteoglycan), and ${\alpha}$ -smooth muscle actin. Tissue inhibitor of metalloproteinase known as the enzyme controlling extracellular matrix with matrix metalloproteinase is more highly expressed in PDL cells, osteoprotegerin known as osteoclastogenesis inhibitory factor is more highly expressed in HGFs. We performed northern blot to verify cDNA microarray results on selected genes such as tissue inhibitor of metalloproteinase, fibronectin, osteoprogeterin. The result of northern blot analysis showed that each cell expressed the genes in similar pattern with cDNA microarray result. This result indicates that cDNA microarray is a reliable method in screening of gene expression profiles.

• The Journal of Korean Academic Society of Nursing Education
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• v.8 no.1
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• pp.51-60
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• 2002

The purpose of this study was to identify the relationship between self-esteem, self- efficacy and clinical practice performance, academic achievement, decision making of major field in clinical practice . The study subjects consisted with 244 students from G. junior nursing college that will adapt a new majoring program of clinical nursing practice funded by Ministry of human and resources development. Data were analyzed using descriptive statistics, and t-test, Pearson correlation, and multiple regression. The results of this study were summarized as follows: 1. The students were relatively performed well in clinical practice setting (total M :3.78). The item of student's personal relationship between patients, patient's family, and professional staff showed high score (M=3.96). However students did not feel comfortable to communicate with patients, patient's family and professional staffs in clinical setting(mean=3.56). 2. Students who had experiences of temporal absence from school showed significant difference in the variable of academic achievement and decision making of major field in clinical practice Students who entered to nursing school with self-motive revealed statistically significant difference in the variable of clinical practice performance, academic achievement, self-esteem, self-efficacy, and decision making of major field in clinical practice. 3. There was a significant correlation between self-esteem and clinical practice performance, (r=.512, p<.000). And the relation between self-esteem and decision making of major field in clinical practice was significantly correlated(r=.377, p<.000). Self-efficacy and clinical practice performance(r=.567, p<.000), and decision making of major field in clinical practice (r=.441, p<.000) showed significant correlations. Also relation between academic achievement and self-esteem reveled a significant correlation(r=.129, p<.05) but correlation between self-efficacy and academic achievement was not significant. 4. Correlation between clinical practice performance and decision making of major field in clinical practice also identified a significant relation(r=.498, p<.000). 5. Self-esteem and self-efficacy variables predicted clinical practice performance and explained 37.7% of clinical practice performance. 6. Aptitude and personal interests(m=4.07) reveled important factor affecting to select majoring area in clinical practice, and advice from parents reflected low percentage on selecting places(m=2.42). In conclusion, the variables of self-esteem and self-efficacy showed significant correlations with the variables of student's clinical practice performance, academic achievement, and decision making of major field in clinical practice. Thus it is recommended that student's affective domain of self-esteem and self-efficacy should be developed by nursing intervention before clinical nursing education.

• Korean Chemical Engineering Research
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• v.58 no.1
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• pp.64-68
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• 2020

In this study, metal copper clad laminate can be prepared using epoxy composite filled with thermally conductive fillers. In order to improve the thermal conductivity of epoxy composites, it is important factor to form conductive networks through appropriate packing of conductive fillers in epoxy composite matrix and to decrease the amount of thermally resistant junctions involving a epoxy composite matrix layer between adjacent filler units. This is because epoxy has a thermal conductivity of only 0.2-0.3W, so in order to maintain high thermal conductivity, thermally conductive fillers are connected to each other, so that the gap between particles can be reduced to reduce thermal resistance. The purpose of this study is to find way to achieve highly thermally conductive in the epoxy composite matrix filled with Al₂O₃ and Boron Nitride(BN) filler by filler loading and uniform dispersion. As a results, the use of Al₂O₃/BN hybrid filler in epoxy matrix was found to be effective in increasing thermal conductivity of epoxy composite matrix due to the enhanced connectivity offered by more continuous thermally conductive pathways and uniform dispersion without interfacial voids in epoxy composite matrix. In addition, surface treatmented s-BN improves the filler dispersion and adhesion between the filler and the epoxy matrix, which can significantly decrease the interfacial thermal resistance and increase the thermal conductivity of epoxy composite matrix.

• KDI Journal of Economic Policy
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• v.32 no.2
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• pp.1-26
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• 2010

This paper empirically examines whether Korean monetary policy is independent of U.S. monetary policy during the post-crisis period in which capital account is liberalized and floating exchange rate regime is adopted and during the pre-crisis period in which capital mobility is restricted and tightly managed exchange rate regime is adopted. Before capital account liberalization, monetary autonomy can be achieved in view of the trillema, even under tightly managed exchange rate regime, as capital mobility is restricted. On the other hand, for the period after capital account liberalization, monetary autonomy can be also achieved in view of the trillema, as exchange rate stability is given up. Securing monetary autonomy, however, may not be easy under liberalized capital account for a small open economy like Korea. Huge capital movements can generate excessive instability in foreign exchange and asset markets. Strengthened international economic linkages may also be another factor to prevent monetary policy from being independent. Using block-exogenous structural VAR model, the effects of U.S. monetary policy shocks on Korean economy are examined. Empirical results show that Korean monetary policy is not independent of U.S. monetary policy for both periods before and after capital account liberalization. For the period after capital account liberalization, Korea does not seem to have implemented floating exchange rate policy in practice, which may lead Korean monetary policy to be dependent on U.S. monetary policy. For the period after capital account liberalization, portfolio flows respond dramatically to the U.S. monetary policy, which may also keep Korean monetary policy from being independent.

• Journal of Technologic Dentistry
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• v.35 no.2
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• pp.157-171
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• 2013

Purpose: This study aims to present a database for the development of a healthcare management program based on the survey and analysis of self reported psychosomatic symptoms among the current dental technology students. Methods: Subjects of our study are 480 dental technology major students enrolled in a third year college located Gyeonggi, Chungcheong, and Gangwon province. Using a random sampling, we conducted a self-report survey from August 30, 2011 to October 28, 2011 and 418 reports were collected as feedback and we put an analysis on them. Results: 1. The average physical self symptom was 20.49, which is higher than the average mental self symptom(18.54). Of the subcategories of psychosomatic self symptom, we observed multiple subjective symptoms as the highest one(37.77), and aggression as the lowest(13.77). 2. As to gender, both physical and mental self symptom were statistically significant with the scale score of(p<.001). The scale score of subcategories is as follows; multiple subjective symptoms(I, p<.001), eye and skin(B, p<.001), digestive(C, p<.001), impulsiveness(H, p<.001), lie scale(L, p<.001), mental instability(J, p<.001), depression(K, p<.001), aggression(F, p<.001), irregularity of life(G, p<.001), mouth and anal(D, p<.05), nervousness(E, p<.05). 3. As for obesity, statistical significance was shown with the scale scores of physical self symptom(p<.001), multiple subjective symptoms(I, p<.001), digestive(C, p<.001), aggression(F, p<.001), depression(K, p<.01), irregularity of life(G, p<.01), respiratory(A, p<.05), eye and skin(B, p<.05), impulsiveness(H, p<.05), mental instability(J, p<.05). The scale scores in the environmental quality and life satisfaction were shown as follows; depression(K, p<.001), lie scale(L, p<.01), and irregularity of life(G, p<.05). 4. We employed multiple regression analysis to take account of general factors affecting psychosomatic self symptoms, and drew that the explanatory power of the model was proved with the scales of physical self symptom(4.1%) and mental self-symptom(3.6%). Obesity was a factor that affects physical self symptom with the scale score of(p<.01), and environmental quality and life satisfaction(p<.01) and obesity(p<.05) affect mental self symptom. Conclusion: In this analysis we observed obesity of dental technology students can influence their psychosomatic self symptoms. In this sense, it would be reasonable to develop a healthcare management and education programs that help the students maintain a healthy weight and promote their health.

• Journal of Distribution Science
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• v.15 no.3
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• pp.61-72
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• 2017

Purpose - The ICT development is affecting the consumer behaviors in selecting channel or distribution system. This study aims to advance the theory on the influence and interaction with omni-channel behaviors. Specifically, analyzing moderating variable is category knowledge that effect between propensity of brand loyalty and its precedence factor which is perceived difference, perceived value, authenticity and consumer-brand relationship. Research design, data, and methodology - The subject of this research is consumers who purchase goods in omni-channel situation. The hypothesis of this research is derived from the literature of the preceding research analysis on brand loyalty, omni-channel and consumer behaviors. This study have constructs that were defined operationally with reference to previous studies, and the research model was designed to figure out the structural relationship among perceived difference, perceived value, authenticity, consumer-brand relationship and brand loyalty. From 2016 Sept. 1 to Dec. 31, a questionnaire survey was performed targeting customers using omni-channel. 327 questionnaire survey had conducted. 316 survey data were used for empirical analysis except data that had missing and wrong value. AMOS(structural equation) was used to confirm the hypothesis which developed by researcher. Results - The results of this study are as follows. First, an authenticity has significant effect on brand loyalty. Second, in the omni-channel situation, but perceived differentiation, perceived value, consumer-brand relationship does not affect brand loyalty. According to this result, it is judged that it is easy to search for information in the situation of omni-channel and integrated decision making is done without distinction between channels. Third, category knowledge has moderating effect between brand loyalty and precedence factors. When the category knowledge level is low, preceding factors have a significant effect on brand loyalty. when the category knowledge level is high, the preceding factors did not have a significant effect on brand loyalty except the authenticity. Conclusions - This study finds out omni-channel's phenomenon is different from other distribution channel phenomenon. In the situation of omni-channel, it is suggested that brand loyalty may be relatively low for a certain brand because it raises the knowledge level of the category. Then this study provides a managerial implications based on the role of the moderate effect on category knowledge, brand loyalty and omni-channel.

• Journal of the korean academy of Pediatric Dentistry
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• v.45 no.1
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• pp.1-9
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• 2018

The purpose of this study is to identify the factors affecting the treatment outcome after surgical-orthodontic treatment of the maxillary impacted incisors using multiple regression analysis. The study enrolled 83 patients who had surgical-orthodontic treatment in impacted maxillary central incisor between January 2005 and December 2015. Possible explanatory variables related to the prognosis of impacted incisor were age, gender, tooth developmental stage, height, position and angle of the teeth. The results of multiple regression analysis showed that as the height of the stem cell from apical papilla (SCAP) increased, the tooth length ratio increased by 0.345 units (p < 0.01). There was no statistically significant difference in gender, tooth development stage, distance and angle between the center line and the tooth, and the height of incisal tip of the tooth. In conclusion, the height of the SCAP of the impacted central incisor is factor affecting the tooth length after orthodontic traction.

• The Journal of the Korea Contents Association
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• v.20 no.3
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• pp.298-308
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• 2020

This study was designed to verify reliability and feasibility by analyzing elderly drivers' ability test tools for older drivers aged 65 or older, which were improved in 2018 and are currently being conducted by the Korea Highway Traffic Authority. Only those aged 65 or older who voluntarily applied to the elderly driving ability evaluation system implemented by the Seoul branch of the Korea Highway Traffic Authority. The research was conducted for about 50 days until Aug. 31, 2018, starting with the registration and inspection of the first study subjects. The analysis performed a correlation analysis with existing tools and cognitive testing tools (MMSE_K) to determine their feasibility and reliability as an improved tool in 2018. As a result, the first, the speed distance, time-space memory, and dispersionism of each sub-component of the old version showed statistically significant static correlation with the sub-factor of the current version. Persistence, on the other hand, was not statistically significant to the current version. The limitations of this study were as follows. Most of the people in the study were highly educated and residents in the metropolitan area. Therefore, it is likely that the results of MSE_K, which checks cognitive and judgment skills, have been upgraded. Also, cognitive tools that are measured by computers are likely to have real measurement errors for generations who are not familiar with computers. Therefore, it is expected that improvement and development of tools for improving the limit points at the site and assessing actual operation capability will be required.

• Korean Journal of Environmental Agriculture
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• v.26 no.2
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• pp.116-123
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• 2007

This experiment was conducted to investigate the distribution and burden characteristics of heavy metals in the rainwater sampled at Suwon area, in the middle part of Korea, from April 2002 to October 2003. The relationship between concentration of heavy metal and other chemical properties in the rainwater was also evaluated. Chemical properties in the rainwater were various differences with raining periods and years. It appeared that a weighted average pH of rainwater was ranged from 4.7 to 5.5. Heavy metal concentrations in the rainwater were ranked as Zn>Pb>Cu>Ni>Cr>As>Cd. As compared with heavy metal concentrations of rainwater in 2002, Cd, Cu and As were higher than other element in 2003. There were positive correlation between major ionic components, such as Ca, Mg, and K, and heavy metal concentrations of rainwater, and As, CU, Cu, Zn and Ni were relatively higher relationship than Pb and Cr in respective to correlation coefficient. For heavy metal distribution of rainwater, the order of average enrichment factors was Cd>Pb>AS>Cu>Zn>Ni>Cr, and these were relatively higher than the natural component such as Fe, Mg and Ca. The monthly enrichment factors were relatively high in the spring (from April to May) at Suwon. The monthly amount of heavy metal precipitation was high in the rainy season from June to August because of great influence of rainfall.

• Journal of the Korean Society of Marine Environment & Safety
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• v.16 no.2
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• pp.169-174
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• 2010

To obtain more accurate meteorological data for analyzing the river discharge characteristics at the Nakdong River Estuary, we investigated the characteristics of the release barrage discharge observed during the 13-year period from 1996 to 2008 and calculated the differences using meteorological data for the Busan and Gimhae weather stations. The river discharge estimated using a tank model was compared to the real river barrage discharge. We discussed the correlation between the discharge and the meteorological factors that affected the estuary water environment. This study found that total annual discharge from the Nakdong river basin for the 13 years was $272,653.3{\times}10^6\;m^3$/month. The largest monthly mean release discharge occurred in July at $73,212.9{\times}10^6\;m^3$/month (26.9% for the year), followed by August and September in that order with 22.0% and 18.9%, respectively.