• The Journal of Korean Academy of Prosthodontics
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• v.41 no.1
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• pp.81-88
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• 2003

Resin-bonded bridge has been an alternative to conventional bridge, since resin-bonded bridge has many attractive advantages such as minimal tooth preparation, short chair time and low cost over conventional bridge. Unfortunately, however, it was reported that resin-bonded bridge showed high failure rate from debonding of retainer in spite of consecutive advances in preparation and materials. And it was shown that multiple abutments were more likely to fail. The majority of debonding failure was considered due to the mobility of the abutment during function. In this view, recently, modification in resin-bonded bridge design was tried. Single retainer, single pontic. 2-unit cantilevered resin-bonded bridge was applied to clinical performance and was shown as retentive or more retentive than fixed-fixed type resin-bonded bridge. This was consistent with the results of studies in 2-unit cantilevered resin-bonded bridges made with all ceramic, In-ceram. The purpose of this article was to overview principles of design and to analyze clinical results of 2-unit cantilevered resin-bonded bridge in comparison with the reports of fixed-fixed resin-bonded bridge.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.20 no.1
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• pp.46-54
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• 2012

One major safety issue of surface operations is the occurrence of runway incursions. Runway incursions are the consequence of multiple operational and/or environmental factors. Human error is known to contribute to almost every runway incursion. One major contributing factor for runway incursion is crew's lack of situational awareness during airport surface operations, induced by weather considerations, by complex airport factors or by crew technique itself; it is also caused by ATC issues. Various airport factors may affect pilot situational awareness, distract the crew, or lead to crew confusion. The recommendations to avoid runway incursions are manifold; Proper Crew's CRM/TEM skills, adequate communication technique, proper knowledge of airport surface markings, lights and signs and preparation of preparation of expected taxi out/in routing. Also runway incursion risk assessment on specific airport before flight may lead to aware of risk level and contribute to prevent runway incursion.

• Archives of Pharmacal Research
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• v.29 no.6
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• pp.503-507
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• 2006

Flavonoids are known as natural anti-inflammatory agents. In this investigation, an anti-inflammatory potential of new topical preparation (SK Ato $Formula^{\circledR}$) containing flavonoid mixtures from Scutellaria baicalensis Georgi roots and Ginkgo biloba L. leaves with an extract of Gentiana scabra Bunge roots was evaluated in an animal model of chronic skin inflammation. Multiple 12-O-tetradecanoylphorbol-13-acetate treatments for 7 consecutive days on ICR mouse ear provoked a chronic type of skin inflammation: dermal edema, epidermal hyperplasia and infiltration of inflammatory cells. When topically applied in this model, this row formulation $(5-20\;{\mu}L/ear/treatment)$ reduced these responses. Furthermore, it inhibited prostaglandin $E_2$ generation (17.1-33.3%) and suppressed the expression of proinflammatory genes, cyclooxygenase-2 and $interleulin-1{\beta}$ in the skin lesion. Although the potency of inhibition was lower than that of prednisolone, all these results suggest that Ato $Formula^{\circledR}$ may be beneficial for treating chronic skin inflammatory disorders such as atopic dermatitis.

• Smart Structures and Systems
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• v.29 no.1
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• pp.207-220
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• 2022

Structural health monitoring (SHM) plays a vital role in the maintenance and operation of constructions. In recent years, autonomous inspection has received considerable attention because conventional monitoring methods are inefficient and expensive to some extent. To develop autonomous inspection, a potential approach of crack identification is needed to locate defects. Therefore, this study exploits two deep learning-based segmentation models, DeepLabv3+ and Mask R-CNN, for crack segmentation because these two segmentation models can outperform other similar models on public datasets. Additionally, impacts of label quality on model performance are explored to obtain an empirical guideline on the preparation of image datasets. The influence of image cropping and label refining are also investigated, and different strategies are applied to the dataset, resulting in six alternated datasets. By conducting experiments with these datasets, the highest mean Intersection-over-Union (mIoU), 75%, is achieved by Mask R-CNN. The rise in the percentage of annotations by image cropping improves model performance while the label refining has opposite effects on the two models. As the label refining results in fewer error annotations of cracks, this modification enhances the performance of DeepLabv3+. Instead, the performance of Mask R-CNN decreases because fragmented annotations may mistake an instance as multiple instances. To sum up, both DeepLabv3+ and Mask R-CNN are capable of crack identification, and an empirical guideline on the data preparation is presented to strengthen identification successfulness via image cropping and label refining.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.12
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• pp.7231-7238
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• 2014

This study examined the effects of self-efficacy on career maturity in dental hygiene students, and whether there were differences in self-efficacy according to the existence or not regarding the certificate of qualifications, participating experience in vocational training competition and award one in the competition. The data was collected from a self-administrated questionnaire on dental hygiene students. The 435 students were selected for this study. The data was analyzed by descriptive analysis, Pearson Correlation, and multiple regression analysis. The results of this study were as follows. First, the task difficulty self-efficacy as a career decision, career independence, career certainty, and career preparation had a positive impact. Second, the self-regulation self-efficacy as a career independence, career confidence, career preparation, and career objectives had a positive impact. Third, the main career attitude and maturity factors affecting the efficacy of dental hygiene students was a career student independence, career preparation, and career certainty. The total explanatory power was 28%. As a result of this research, comprehensive implications were suggested to improve the career maturity and enhance the adjustment to college.

• Restorative Dentistry and Endodontics
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• v.44 no.2
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• pp.22.1-22.8
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• 2019

Objectives: The aim of this study was to investigate the effect of glide path preparation with PathFile and ProGlider nickel-titanium (NiTi) files on the cyclic fatigue resistance of WaveOne NiTi files. Materials and Methods: Forty-four WaveOne Primary files were used and divided into four groups (n = 11). In the first group (0 WaveOne), the WaveOne Primary files served as a control group and were not used on acrylic blocks. In the 1 WaveOne Group, acrylic blocks were prepared using only WaveOne Primary files, and in the PF+WaveOne group and PG+WaveOne groups, acrylic blocks were first prepared with PathFile or ProGlider NiTi files, respectively, followed by the use of WaveOne Primary files. All the WaveOne Primary files were then subjected to cyclic fatigue testing. The number of cycles to failure was calculated and the data were statistically analyzed using one-way analysis of variance (ANOVA) and the Tukey honest significant difference multiple-comparison test at a 5% significance level. Results: The highest number of cycles to failure was found in the control group, and the lowest numbers were found in the 1 WaveOne group and the PF+WaveOne group. Significant differences were found among the 1 WaveOne, PF+WaveOne, and control groups (p < 0.05). No statistically significant differences were found between the PG+WaveOne group and the other three groups (p > 0.05). Conclusion: Glide path preparation with NiTi rotary files did not affect the cyclic fatigue resistance of WaveOne Primary files used on acrylic blocks.

• Restorative Dentistry and Endodontics
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• v.46 no.2
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• pp.16.1-16.11
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• 2021

Objectives: The aim of this study was to evaluate the shaping ability of the TruShape and Reciproc Blue systems and the apical extrusion of debris after root canal instrumentation. The ProTaper Universal system was used as a reference for comparison. Materials and Methods: Thirty-three mandibular premolars with a single canal were scanned using micro-computed tomography and were matched into 3 groups (n = 11) according to the instrumentation system: TruShape, Reciproc Blue and ProTaper Universal. The teeth were accessed and mounted in an apparatus with agarose gel, which simulated apical resistance provided by the periapical tissue and enabled the collection of apically extruded debris. During root canal preparation, 2.5% sodium hypochlorite was used as an irrigant. The samples were scanned again after instrumentation. The percentage of unprepared area, removed dentin, and volume of apically extruded debris were analyzed. The data were analyzed using 1-way analysis of variance and the Tukey test for multiple comparisons at a 5% significance level. Results: No significant differences in the percentage of unprepared area were observed among the systems (p > 0.05). ProTaper Universal presented a higher percentage of dentin removal than the TruShape and Reciproc Blue systems (p < 0.05). The systems produced similar volumes of apically extruded debris (p > 0.05). Conclusions: All systems caused apically extruded debris, without any significant differences among them. TruShape, Reciproc Blue, and ProTaper Universal presented similar percentages of unprepared area after root canal instrumentation; however, ProTaper Universal was associated with higher dentin removal than the other systems.

• Journal of Hospice and Palliative Care
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• v.19 no.3
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• pp.222-232
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• 2016

Purpose: This study was to investigate the relationships between spiritual well-being, attitude towards death and perception of hospice, and the factors influencing hospice perception of high school students. Methods: A survey was conducted with 229 students in four high schools in B city from May 1, 2015 through May 31, 2015. The data were analyzed with descriptive statistics, t-test, ANOVA, Pearson correlation coefficients, stepwise multiple regression using the SPSS 18.0 program. This study was approved by the internal review board. Results: The factors influencing hospice perception of the high school students were previous recognition of hospice (${\beta}=0.412$, P<0.001), attitude towards death preparation among sub-variables of attitude towards death (${\beta}=-0.244$, P<0.001), subjective school life satisfaction (${\beta}=-0.215$, P<0.001), and sex (${\beta}=0.191$, P<0.001). The more positive the attitude towards my body after death and that towards death preparation was, the more positive recognition for hospice was. The total explanatory power of these factors was 34.5%. Conclusion: To improve high school students' perception of hospice, it is necessary to provide them with a hospice education program to help them with their attitudes towards death preparation and their understanding of hospice.

• The Journal of the Convergence on Culture Technology
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• v.9 no.4
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• pp.383-392
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• 2023

This study was a descriptive survey study for nursing college students to identify disaster awareness, attitude, disaster preparation, nursing professionals, social support, and disaster nursing capabilities, and to prepare measures to improve disaster nursing capabilities by identifying predictors of disaster nursing capabilities. Data collection was collected from 160 nursing students in G-do from March 27 to April 7, 2023, and a total of 158 copies were finally analyzed. Using the SPSS Win. 25.0 program, technical statistics, t-test, one-way ANOVA, Pearson correlation coefficient, and hierarchical multiple regression were analyzed. The result show that fourth grade(β=.20, p=.027), disaster nursing education is 'existent'(β=.15, p=.041), disaster readiness(β=.27, p<.001) nursing professional(β=.21, p=.012) was found to be a significant predictor of disaster nursing competency. Disaster preparation was found to be the best predictor of disaster nursing competency, followed by "nursing professionals," "fourth grade," and "disaster nursing education" with 26.3% of explanatory power. According to the findings of this study, it is necessary to develop an integrated education program for disaster nursing practice that can enhance awareness of disasters, attitudes toward disasters, disaster preparation, nursing professionals, and social support.

• Journal of Digital Convergence
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• v.10 no.9
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• pp.239-251
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• 2012

This study aims to seek the policies and the plans for the successful small business start-up through an exploratory study about the factors affecting the success rate of small business start-up. To measure the performance of the start-up business(sales revenue, net profit, and outcome expectancy), the characteristics of founders (experience, psychological characteristics) and the preparation of small business start-up were measured as independent variables and the self-efficacy was measured as a parameter. 427 small business owners were targeted and structured self-administered questionnaires were collected from them. For the data process, a multiple regression analysis by SPSS 18.0 was conducted. The findings demonstrated the experience in the same business, the need for achievement, the risk-taking propensity, the preparation period for business start-up had a significant effect on self-efficacy, and experience of failure and the ratio of net worth had a significant effect on sales revenue and net profit, and the locus of control had a significant effect on outcome expectancy through the self-efficacy, a parameter. It was also noted the self-efficacy of small business owners and the business performance varied depending on the characteristics of them and the preparation process of the business start-up. Based on the those findings, the theoretical and practical implications were discussed and the suggestions about the limits of the study, future policies and studies were made.