• Korean Journal of Dental Materials
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• v.44 no.2
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• pp.151-161
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• 2017

The purpose of this study was to examine the effect of shade and thickness of resin-nanoceramic CAD-CAM block (RNB) on the microhardness of dual-cured resin cement, as well as to measure the number of photons transmitted through RNBs of different thicknesses and colors. One dual-cured resin cement was used to prepare resin cement specimens. Resin cement specimens were light-cured for 40 seconds through 3 shades (A1, A2, A3 in HT (high translucency) and LT (low translucency) respectively) and four thicknesses (1, 2, 3, 4 mm) of RNB specimens. Vickers microhardness measurements of resin cement specimens were performed using a Vickers hardness tester. The light transmission of RNB specimens was measured using a spectrometer (SpectroPro-500, Acton Research, Acton, MA, U.S.A.), and the translucency parameter was calculated using the CIEL*a*b* system. Data were statistically analyzed by ANOVA and Tukey's test. There was a significant decrease of microhardness of resin cement specimen with an overlay of 4 mm of RNB thickness and A3 shade in comparison to A1 and 1 mm, respectively (p<0.05). The translucency parameter values and light transmission of RNBs tested differed significantly, according to the thicknesses of the specimen (p<0.05). Light transmission is decreased with increase in the thicknesses of RNBs. Shade A1 transmitted more light than darker blocks. A decrease in microhardness of resin cement specimens was observed with increasing thickness and shade (A1 to A3) of RNBs.

• Journal of Korean Home Economics Education Association
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• v.33 no.1
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• pp.1-16
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• 2021

The purpose of this study was to investigate the needs of middle school students for the practical reasoning in a distance learning environment, to verify the needs differences based on the learner's personal characteristics, student-teacher interaction, and student-student interaction, and to investigate the relationships among student-teacher interaction, voluntary participation of students, and the students' perception of the extent to which practical reasoning is implemented in distance learning. For this purpose, 1,842 middle school students from seven schools in Gyeonggi, Daejeon, Chungbuk, and Sejong areas were surveyed online to investigate the importance of the practical reasoning questions and the how much practical reasoning is implemented in current distance learning. Among them, 1,095 responses were used for final analysis and descriptive statistics, independent sample t-test, one-way ANOVA, and path analysis were conducted. As a result of the study, first, middle school students acknowledged that the practical reasoning was important with the importance average 3.76. Based on the locus for focus model, the priorities of the needs in home economics class were examined, and the values and importance of the problem, and the ramification of the solution were considered to be of high priority. Second, characteristics of middle school students, student-teacher interaction and student-student interaction were found to have positive influence on needs for practical reasoning, while no difference were found by gender or voluntary participation in distance learning. Third, the voluntary participation of students and the student-teacher interaction in distance learning had a positive (+) significant effect on perceived implementation of practical reasoning, yet negative (-) significant effect on needs for practical reasoning.

• 한국노년학
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• v.38 no.3
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• pp.551-567
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• 2018

Demographic and socio-structural information is useful to identify potential welfare recipients who are in need of disease-prevention and intervention services. Thus, the present study aims to explore the differences in grip strength among middle and old-aged adults by living conditions and by living area. The 5th wave data of Korean Longitudinal Study of Aging was utilized. The dependent variable was grip strength, and the independent variables were living alone (living alone or not) and living area (city or non-city). Covariates were age, education, log-transformed household income, spouse existence, body mass index, self-rated health conditions, depressive symptoms, cognitive function, smoking, regular exercise, frequency of meeting with friends, and the number of social participation. Regression analysis was performed for middle-aged men, middle-aged women, old-aged men, and old-aged women, respectively. ANOVA and Chi-test were additionally used to specifically discuss significant results. Cross-sectional weight was applied to all analyses. According to the results, living alone and living area did not have significant effects on grip strength among middle-aged men, old-aged men, and old-aged women. In middle-aged women, however, living alone and living area were significantly associated with grip strength. To be specific, middle-aged women who lived alone in rural areas had the lowest grip strength compared to other middle-aged women. Additional analysis showed that middle-aged women who lived alone in rural areas had risk factors, such as low education level, low income, or high depressive symptoms. It implies that middle-aged women living alone in rural areas may have physical health risks, so they might be in need of disease prevention. This study is meaningful in that it can provide reliable information on the latent welfare recipients by using representative panel data and applying weight values.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.1
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• pp.376-383
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• 2019

This study was conducted to investigate academic self-efficacy, critical thinking disposition, and learning motivation, which influence problem solving ability in nursing students. Data were collected from June 4, 2018 to June 29, 2018, and the final 213 data points were used for analysis. The SPSS/WIN 22.0 program was used to conduct descriptive statics, Pearson's correlation coefficient, t-tests, ANOVA, Scheffe's test and multiple regression analysis. The problem solving ability according to the general characteristics differed among residential type (F=3.930, p=0.021) and satisfaction with major (F=4.618, p=0.011). In the correlation between academic self-efficacy, critical thinking disposition, learning motivation, and problem solving ability of the subject, academic self-efficacy (r=0.573, p<0.001), critical thinking disposition (r=0.620, p<0.001), and learning motivation (r=0.563, p<0.001). The factors affecting the problem solving ability of the study subjects were major satisfaction (${\beta}=.117$, p=0.036), academic self-efficacy (${\beta}=0.314$, p<0.001), critical thinking disposition (${\beta}=0.318$, p<0.001), and learning motivation (${\beta}=0.217$, p=0.004), with an explanatory power of 45.2%. In this study, it is necessary to confirm the effects of the development of the intervention program and the application of the program, which can improve the problem solving ability of nursing students.

• Journal of the Korean Society of Radiology
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• v.12 no.6
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• pp.727-735
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• 2018

Targeting the radiological technologists working in Gyoungsangnam province, this study was performed to obtain the fundamental data to improve the competency and right awareness of the hospital infection management, and to educate infection management of radiological technologists by analyzing the status, awareness, and performance of the hospital infection management. During April 1, 2018 to April 31, 2015, after we sent out a total of 400 questionnaires for the survey to radiological technologists working at the clinic located in Gyoungsangnam province, 320 questionnaires suitable for research were analysis by using SPSS 18.0 statistical analysis software. As the hospital infection management factors, 5 items for hospital infection and 60 items of the awareness and performance for the hospital infection management were used. 60 items of the awareness and performance for the hospital infection management were consisted hand hygiene, personal hygiene and clothing, medical equipment and supplies, cleaning and waste, examination and environment. And as the sociodemographic characteristics, the gender, marriage, age, level of education, working organization, working period, and working department were used. Consequentially, the awareness for the hospital infection management($4.19{\pm}.60$) and the performance($4.22{\pm}.52$) were confirmed as high level. Using these results, the hospital infection management level of the radiological technologists working in Gyoungsangnam province was found to be high in arareness and performance of hospital infection management. There was a significant correlation between the degree of awareness and performance of radiological technologists for hospital infection management. Furthermore, in the multiple regression analysis of cognitive factors on performance, it was found that 66.1% explanatory power had a significant positive influence. In order to improve the awareness of hospital infection management of radiological technologist working in various departments, the infection management education and improvement of hospital work environment are necessary. And also, It is important to participate actively in hospital infection management and preventive education and to play a pivotal role in securing expertise in hospital infection management.

• Sleep Medicine and Psychophysiology
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• v.25 no.2
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• pp.51-57
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• 2018

Objectives: Previous studies have shown that periodic limb movements in sleep (PLMS) could be one of risk factors for cardiovascular morbidity. The purpose of this study was to investigate the association between PLMS and blood pressure changes during sleep. Methods: We analyzed data from 358 adults (176 men and 182 women) aged 18 years and older who were free from sleep apnea syndrome (Respiratory Disturbance Index < 5) and sleep disorders such as REM sleep behavior disorder or narcolepsy. Demographic characteristics, polysomnography records, and clinical variable data including blood pressure, body mass index, alcohol, smoking, and current medications were collected. In addition, self-report questionnaires including the Beck Depression Index, Epworth Sleepiness Scale and Pittsburgh Sleep Quality Index were completed. Blood pressure change from bedtime to awakening was compared between the two periodic limb movement index (PLMI) groups [low PLMI ($PLMI{\leq}15$) and high PLMI (PLMI > 15)]. Blood pressure change patterns were compared using repeated measures analysis of variance. Results: Systolic blood pressure in the high PLMI group was lower than that in the low PLMI group (p = 0.036). These results were also significant when adjusted for gender and age, but were not statistically significant when adjusted for BMI, alcohol, smoking, anti-hypertension medication use and sleep efficiency (p = 0.098). Systolic blood pressure dropped by 9.7 mm Hg in the low PLMI group, and systolic blood pressure in the high PLMI group dropped by 2.9 mm Hg. There was a significant difference in delta systolic blood pressure after sleep between the two groups in women when adjusted for age, BMI, alcohol, smoking, antihypertensive medication use and sleep efficiency (p = 0.023). Conclusion: PLMS was significantly associated with a decreasing pattern in nocturnal BP during sleep, and this association remained significant in women when adjusted for age, BMI, alcohol, smoking, antihypertension medication use and sleep efficiency related to blood pressure. We suggest that PLMS may be associated with cardiovascular morbidity.

• Journal of Nutrition and Health
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• v.52 no.5
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• pp.488-500
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• 2019

Purpose: This study examined the effects of a mobile app-based program to reduce the dietary sugar intake according to the stages of the behavioral change in dietary sugar reduction in female college students. Methods: The program used in this study can monitor the dietary sugar intake after recording the dietary intake and provide education message for the reduction of dietary sugar intake. In an eight-week pre-post intervention study, 68 female college students were instructed to record all the food they consumed daily and received weekly education information. At pre-post intervention, the subjects were asked to answer the questionnaire about sugar-related nutrition knowledge, sugar-intake behavior, and sugar-intake frequency. For statistical analysis, ANOVA and a paired t-test were used for comparative analysis according Precontemplation (PC), Contemplation Preparation (C P), and A M (Action Maintenance) stage. Results: Significant differences were observed in the frequency of snacking, experience of nutrition education, and preference for sweetness according to the stages of behavior change in dietary sugar reduction. After finishing an intervention, the sugar-related nutrition knowledge score was increased significantly in the stages of Precontemplation (PC) and Contemplation Preparation (C P). The score of the sugar intake behavior increased significantly in all stages. The intake frequency of chocolate, muffins or cakes, and drinking yogurt decreased significantly in the PC stage and the intake frequency of biscuits, carbonated beverages, and fruit juice decreased significantly in the C P stage. Subjects in the PC and C P stages had an undesirable propensity in nutrition knowledge, sugar-intake behavior, and sugar-intake frequency compared to the A M stage, but this intervention improved significantly their nutrition knowledge, sugar-intake behavior, and sugar-intake frequency. Conclusion: This program can be an effective educational tool in the stages of PC and C P, and is expected to further increase the usability and sustainability of mobile application if supplemented appropriately to a health platform program.

• Journal of the Korean Society for information Management
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• v.36 no.1
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• pp.137-168
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• 2019

This study measures and analyzes the university library user's sense of community, service quality assessment, user satisfaction and loyalty. In addition, the effect of the university library user's sense of community on university library user satisfaction and loyalty mediated by the assessment of the quality of service is investigated. On the basis of study result, to improve user satisfaction and user loyalty, the direction and implications of library development are presented. In order to achieve the purpose of the study, precedent research and literature were investigated, and the study model and hypothesis were established based on theoretical background. In order to verify the hypothesis, a total of 300 questionnaires were distributed to subject who had experience using the Central Library among undergraduate students at the C National University, and the final 282 sample was used for analysis. To analyze the differences depending on the general characteristics of the samples, It is the result of an independent sample t-test and one-way ANOVA. The results of the mediated effects analysis using the PROCESS macro-programs models 4 and 6 of Hayes for hypothesis testing are as follows. First, The university library user's sense of community (Service Benefits Perception and Satisfaction, Mutual sense of influence) effect the user satisfaction of university library mediated by service quality assessment at statistical significance. This showed that the higher the university library user's sense of community, the higher the service quality assessment, and the higher the user satisfaction level of university library. Second, The university library user's sense of community (Service Benefits Perception and Satisfaction, Mutual sense of influence) effect the user loyalty of university library mediated by service quality assessment and user satisfaction. This showed that the higher the university library user's sense of community, the higher the service quality assessment, the higher user satisfaction level of university library and the higher the user loyalty level of university library. The results of this study showed that the university library user's sense of community has a direct and indirect effect on enhancing user satisfaction and loyalty through the service quality assessment.

• The Korean Journal of Archival Studies
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• no.47
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• pp.95-130
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• 2016

The job satisfaction of records managers is of importance because it affects their work performance and retention. The purpose of this study is to investigate records managers' job satisfaction and to identify factors affecting records manager's job satisfaction to find the way to improve their job satisfaction. Specific questions of the study are as follows: 1) What is the job satisfaction of records managers? 2) Are factors affecting job satisfaction different depending on record managers' personal characteristics? 3) What are the most influential factors on job satisfaction? To do that, questionnaires were used to gather data from 60 domestic records managers working in different types of records centers. Data analyses included descriptive statistics, one-way ANOVA, independent t-test, and multiple-regression analysis. Additionally, interviews with 2 record managers were conducted to collect opinions on factors affecting job dissatisfaction and recommendations for improving their job satisfaction. Important findings of the study are as follows: First, the respondents are moderately satisfied with their jobs (3.2 out of 5 points). The level of job satisfaction is different depending on years of career, years of employment, number of personnel the respondent is working with in the records center, and etc. The number of personnel the respondent is working with was found to be the most influential factor. Second, multiple-regression analysis result shows that motivation factors(satisfaction factors) are more influential than hygiene factors (dissatisfaction factors) on the respondents' job satisfaction, which confirms Herzberg's two factor theory. More specifically, 'work ethic,' one of motivator factors, has the greatest influence, followed by 'procedural impartiality', 'communication', 'job characteristic', 'distributive justice', and 'working conditions.' Based on the results, this study suggests several ways to improve record managers' job satisfaction level. First, the awareness of records management should be increased. The respondents indicated that their job dissatisfaction is usually derived from a lack of the awareness of records management. Therefore, every chief of organizations, National Archives of Korea, and records managers themselves should try to raise the awareness of records management. Especially, records managers should make stronger efforts to attract the office's attention. Second, records managers ought to establish their identity as records management profession. Also, they should participate in various activities of the archival community to overcome the limitation of individuals.

• Journal of Korean Society of Forest Science
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• v.110 no.2
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• pp.198-209
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• 2021

This study evaluated the effects of the dimensional characteristics of containers on the nitrogen status of Quercus serrata, Fraxinus rhynchophylla, and Zelkova serrata in the container nursery stage. Seedlings were grown using 16 container types [four growing densities (100, 144, 196, and 256 seedlings/m²) × four cavity volumes (220, 300, 380, and 460 cm³/cavity)]. Two-way ANOVA was performed to test the differences in nitrogen concentration and seedling content among container types. Additionally, we performed multiple regression analyses to correlate container dimensions and nitrogen content. Container types had a strong influence on nitrogen concentration and the content of the seedling species, with a significant interaction effect between growing density and cavity volume. Cavity volumes were positively correlated with the nitrogen content of the three seedling species, whereas growing density negatively affected those of F. rhynchophylla. Further, nutrient vector analysis revealed that the seedling nutrient loading capacities of the three species, such as efficiency and accumulation, were altered because of the different fertilization effects by container types. The optimal ranges of container dimension by each tree species, obtained multiple regression analysis with nitrogen content, were found to be approximately 180-210 seedlings/m² and 410-460 cm³/cavity for Q. serrata, 100-120 seedlings/m² and 350-420 cm³/cavity for F. rhynchophylla, and 190-220 seedlings/m² and 380-430 cm³/cavity for Z. serrata. This study suggests that an adequate type of container will improve seedling quality with higher nutrient loading capacity production in nursery stages and increase seedling growth in plantation stages.