• The Journal of Advanced Prosthodontics
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• v.14 no.4
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• pp.250-261
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• 2022

PURPOSE. The purpose of this study was to analyze the marginal fit of three-unit resin prostheses printed with the stereolithography (SLA) method in two build orientations (45°, 60°) and two layer thicknesses (50 ㎛, 100 ㎛). MATERIALS AND METHODS. A master model for a three-unit resin prosthesis was designed with two implant abutments. Forty specimens were printed using an SLA 3D printer. The specimens were printed with two build orientations (45°, 60°), and each orientation was printed with two layer thicknesses (50 ㎛, 100 ㎛). The marginal fit was measured as the marginal gap (MG) and absolute marginal discrepancy (AMD), and MG and AMD measurements were performed at 8 points per abutment, for 16 points per specimen. All statistical analyses were performed using SPSS software. Two-way analysis of variance (ANOVA) was separately performed on the MG and AMD values of the build orientations and layer thicknesses. Moreover, one-way ANOVA was performed for each point within each group. RESULTS. The margins of the area adjacent to the pontic showed significantly high values, and the values were smaller when the build orientation was 45° than when it was 60°. However, the margin did not differ significantly according to the layer thicknesses. CONCLUSION. The marginal fit of the three-unit resin prosthesis fabricated by the SLA 3D method was affected by the pontic. Moreover, the marginal fit was affected by the build orientation. The 45° build orientation is recommended.

• Journal of radiological science and technology
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• v.46 no.4
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• pp.325-336
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• 2023

The purpose of this study was to analyze the structural relationship between job satisfaction levels felt during ultrasound examination of radiological technologists (RTs) using a structural equation model. The subjects were a total of 203 RTs currently working in medical institutions. The method was conducted as a survey study using a questionnaire consisting of a total of 29 questions consisting of demographic characteristics and job satisfaction levels that were self-efficacy, job competency, extrinsic compensation, and job satisfaction. The reliability was secured with the Cronbach's alpha coefficient of 0.6 or higher. For statistical analysis, a significant difference between the frequency analysis of demographic characteristics and the mean of the job satisfaction levels were performed by independent sample T-test and one-way analysis of variance (ANOVA) followed by Scheffe's post hoc test. The correlation analysis between variables was tested with Spearman's and Pearson's correlation coefficient. We analyzed the structural relationships between variables by structural equations. As a result, first, job competency and extrinsic compensation had a positive effect on job satisfaction on ultrasound examination of RTs. Second, the self-efficacy of ultrasound examination RTs showed a high correlation with job competency. Third, the job satisfaction levels showed in the order of job competency, job satisfaction, self-efficacy, and extrinsic compensation. In conclusion, this study are expected to be provided as data to identify factors that could improve job satisfaction during ultrasound examination of RTs by empirically analyzing the structural relationship of self-efficacy, job competency, and external compensation.

• Journal of People, Plants, and Environment
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• v.24 no.6
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• pp.629-638
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• 2021

Background and objective: This study was conducted to develop diameter growth models for thinned Quercus glauca Thunb. (QGT) stands to inform production goals for treatment and provide the information necessary for the systematic management of this stands. Methods: This study was conducted on QGT stands, of which initial thinning was completed in 2013 to develop a treatment system. To analyze the tree growth and trait response for each thinning treatment, forestry surveys were conducted in 2014 and 2021, and a one-way analysis of variance (ANOVA) was executed. In addition, non-linear least squares regression of the PROC NLIN procedure was used to develop an optimal diameter growth model. Results: Based on growth and trait analyses, the height and height-to-diameter (H/D) ratio were not different according to treatment plot (p > .05). For the diameter of basal height (DBH), the heavy thinning (HT) treatment plot was significantly larger than the control plot (p < .05). As a result of the development of diameter growth models by treatment plot, the mean squared error (MSE) of the Gompertz polymorphic equation (control: 2.2381, light thinning: 0.8478, and heavy thinning: 0.8679) was the lowest in all treatment plots, and the Shapiro-Wilk statistic was found to follow a normal distribution (p > .95), so it was selected as an equation fit for the diameter growth model. Conclusion: The findings of this study provide basic data for the systematic management of Quercus glauca Thunb. stands. It is necessary to construct permanent sample plots (PSP) that consider stand status, location conditions, and climatic environments.

• The Journal of Advanced Prosthodontics
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• v.3 no.4
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• pp.177-185
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• 2011

PURPOSE. The aim of this study was to evaluate the effect of dimensional stability of splinting material on the accuracy of master casts. MATERIALS AND METHODS. A stainless steel metal model with 6 implants embedded was used as a master model. Implant level impressions were made after square impression copings were splinted using 5 different techniques as follows. (1) Splinted with autopolymerizing resin and sectioned, reconnected to compensate polymerization shrinkage before the impression procedure. (2) Splinted with autopolymerizing resin just before impression procedure. (3) Primary impression made with impression plaster and secondary impression were made over with polyether impression material. (4) Splinted with impression plaster. (5) Splinted with VPS bite registration material. From master model, 5 impressions and 5 experimental casts, total 25 casts were made for each of 5 splinting methods. The distortion values of each splinting methods were measured using coordinate measuring machine, capable of recordings in the x-, y-, z- axes. A one-way analysis of variance (ANOVA) at a confidence level of 95% was used to evaluate the data and Tukey's studentized range test was used to determine significant differences between the groups. RESULTS. Group 1 showed best accuracy followed by Group 3 & 4. Group 2 and 5 showed relatively larger distortion value than other groups. No significant difference was found between group 3, 4, 5 in x-axis, group 2, 3, 4 in y-axis and group 1, 3, 4, 5 in z-axis (P<.0001). CONCLUSION. Both Splinting impression copings with autopolymerizing resin following compensation of polymerization shrinkage and splinting method with impression plaster can enhance the accuracy of master cast and impression plaster can be used simple and effective splinting material for implant impression procedure.

• Journal of the Korea Fashion and Costume Design Association
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• v.25 no.4
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• pp.147-161
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• 2023

This study used 3D anthropometric data from the 8th Size Korea to type and analyze whole body shapes of obese women in their 20s and 30s, and constructed dimensional data for human body items needed to create a 3D human body model for each type. The data analysis used data from 148 obese women in their 20s and 30s, and a total of 48 index values, drop values, and angle items were subjected to factor analysis and one-way variance analysis to categorize body types and verify significant differences by type. As a result of the factor analysis, 12 factors were extracted and divided into 4 body types. Type 1 is a 'standard type with a curved torso with balanced upper and lower body lengths', Type 2 is a 'bending forward type with a short, thick lower body, and an uncurved torso', Type 3 is a 'lean back type with a long and thin lower body and an H-shape torso', Type 4 is a 'sway back type with a long and thick lower body and abdominal obesity'. The representative body type of obese women in their 20s and 30s was identified as Type 1. The constructed body shape information will be used as basic data for future 3D human body modeling.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.12
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• pp.322-332
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• 2019

This is a descriptive research study that aims to identify the effects of professionalism, job satisfaction, and resilience on the retention intention of home visiting nurses from the long-term care insurance system of Korea. Data were collected from self-administered surveys completed by 141 home visiting nurses of registered visiting-nursing institutions in the long-term care insurance database (April 1-May 31, 2019). Analyses were independent t-tests, one-way analysis of variance (ANOVA), the Scheffé test, Pearson's correlation analysis using SPSS/WIN 22.0, and multiple hierarchical regression analyses. Results showed that the mean professionalism score was 3.51/5, 3.27/5 for job satisfaction, 3.79/5 for resilience, and 4.04/5 for retention intention. A positive correlation existed between retention intention and professionalism (r = .272), job satisfaction (r = .201), and resilience (r = .530). The final regression model showed that resilience (β = .455, p < .001) and job satisfaction (β = .175, p = .016) significantly affect retention intention. The variables' model explanation power was 32.0% (F = 11.968, p < .001). The results show the need for strategies to improve resilience, followed by strategies to improve job satisfaction to increase the retention intentions of these home visiting nurses.

• Journal of dental hygiene science
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• v.20 no.1
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• pp.51-58
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• 2020

Background: The present study aimed to provide basic data to establish a foundation for efficient operation of the organization by identifying the effects of factors related to moral sensitivity and psychological well-being on job engagement of clinical dental hygienists. Methods: This cross-sectional survey consisted of self-administration questionnaires. After the approval by the Institutional Review Board, a survey was conducted from September 2019 to November 2019, targeting dental hygienists with clinical experience of 1 year or more. A total of 189 questionnaires were analyzed using SPSS 18.0 for Windows. The data were analyzed using average standard deviation, t-test, one-way analysis of variance, Scheffe test, Pearson's correlation analysis, and multiple regression analysis. Results: According to job-related characteristics, higher job engagement was associated with more amount of clinical experience, less turnover intention, higher positions, and occasional job fatigue. Job engagement was improved by increasing moral sensitivity and psychological well-being of clinical dental hygienists. The factors affecting job engagement revealed that along with clinical career, the sub-areas of job engagement, namely turnover intention, moral sensitivity, and psychological well-being had statistically significant influence on job engagement and the explanatory power of the model was approximately 44.8%. Conclusion: Joy of working as a clinical dental hygienist, clinical career, turnover intention, moral sensitivity, and psychological well-being were confirmed as influencing factors that affected job engagement of clinical dental hygienists. It is necessary to establish an effective plan to improve job engagement by increasing moral sensitivity and psychological well-being of clinical dental hygienists.

• Journal of Korean Academy of Nursing
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• v.49 no.3
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• pp.340-348
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• 2019

Purpose: This study aimed to investigate the nutritional status of liver transplantation (LT) recipients and explore certain factors that influence nutritional status, including dietary patterns and physical activities. Methods: This was a cross-sectional, descriptive study. The subjects included 211 LT recipients at a medical center outpatient clinic located in Seoul, Korea. The nutritional status, dietary patterns, and physical activities of each subject were measured using the body mass index (BMI), Mini Dietary Assessment (MDA), and Global Physical Activity Questionnaire. Independent t-test, one-way analysis of variance, and multiple linear regression analysis were used to analyze the data. Results: The percentages of living and deceased donor LTs were 81.0% and 19.0%, respectively. The mean BMIs pre- and post-LT were 23.88 and $23.16kg/m^2$, respectively, and the average MDA score was 36.55. More than 60.0% of the subjects had a moderate or high level of physical activity. In multivariate analysis, a higher BMI before LT (${\beta}=.72$, p<.001), a lower Model for End-stage Liver Disease (MELD) score (${\beta}=-.18$, p<.001), and being male (${\beta}=-.10$, p=.024) contributed to better nutritional status post-LT. Patients within six months of LT were less engaged in muscle exercises than those post six months of LT (p=.020). Conclusion: LT recipients in Korea have good nutritional status and a good level of physical activity. To improve recipients' post-LT nutritional status, the pre-LT nutritional status should be considered, particularly in those with a higher MELD score. In addition, physical activity including muscle-strengthening exercises should be encouraged from an earlier stage.

• Journal of Home Health Care Nursing
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• v.30 no.1
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• pp.59-68
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• 2023

Purpose: We investigated the association between empathy for the elderly, the nursing work environment, person-centered care, and geriatric nursing practice among university hospital nurses and factors that affect geriatric nursing practice. Method: We administered questionnaires to 178 nurses between May 23 and June 21, 2022 at a university hospital in city D. We used descriptive statistics, the t-test, one-way analysis of variance, the scheffé test, Pearson correlation coefficients, and stepwise multiple regression analysis for data analysis. Results: We observed a statistically significant positive correlation between nurses' geriatric nursing practice and empathy for the elderly, the nursing work environment, and person-centered care. Empathy for the elderly was positively correlated with the nursing work environment and person-centered care, and the nursing work environment showed a statistically significant positive correlation with person-centered care. Empathy for the elderly and the nursing work environment significantly affected geriatric nursing practice. The overall explanatory power of the regression model was 33.4%. Conclusion: Greater awareness and implementation of various educational programs that promote empathy for the elderly are necessary to improve nursing care for the elderly population. Furthermore, adequate manpower and material support are important to improve the nursing work environment among nurses employed at university hospitals.

• Steel and Composite Structures
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• v.49 no.3
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• pp.337-348
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• 2023

Successive wetting and drying cycles of concrete due to weather changes can endanger the safety of engineering structures over time. Considering wetting and drying cycles in concrete tests can lead to a more correct and reliable design of engineering structures. This study aims to provide a model that can be used to estimate the resistance properties of concrete under different wetting and drying cycles. Complex sample preparation methods, the necessity for highly accurate and sensitive instruments, early sample failure, and brittle samples all contribute to the difficulty of measuring the strength of concrete in the laboratory. To address these problems, in this study, the potential ability of six machine learning techniques, including ANN, SVM, RF, KNN, XGBoost, and NB, to predict the concrete's tensile strength was investigated by applying 240 datasets obtained using the Brazilian test (80% for training and 20% for test). In conducting the test, the effect of additives such as glass and polypropylene, as well as the effect of wetting and drying cycles on the tensile strength of concrete, was investigated. Finally, the statistical analysis results revealed that the XGBoost model was the most robust one with R2 = 0.9155, mean absolute error (MAE) = 0.1080 Mpa, and variance accounted for (VAF) = 91.54% to predict the concrete tensile strength. This work's significance is that it allows civil engineers to accurately estimate the tensile strength of different types of concrete. In this way, the high time and cost required for the laboratory tests can be eliminated.