• Journal of the Korean Society for Aviation and Aeronautics
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• v.28 no.2
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• pp.53-62
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• 2020

This study is to evaluate the accuracy of the meteorological information provided for the aircraft operating at low altitude. At first, it is necessary to identify crucial elements of weather information closely related to flight safety during low altitude flights. The study conducted a survey of pilots of low altitude aircraft, divided into pre-flight and in-flight phases, and reached an opinion that wind direction, wind speed, cloud coverage and ceiling and visibility are important items. Related to these items, we compared and calculated the accuracy of TAFs and METARs from Taean Airfield, Seosan Airport and Gunsan Airport because of their high number of domestic low-altitude flights. Accuracy analysis evaluated the accuracy of two numerical variables, Mean Absolute Error(MAE) and Root Mean Square Error(RMSE), and the cloud coverage which is categorical variable was calculated and compared by accuracy. For numeric variables, one-way ANOVA, which is a parameter-test, was approached to identify differences between actual forecast values and observations based on absolute errors for each item derived from the results of MAE and RMSE accuracy analyses. To determine the satisfaction of both normality assumptions and equivalence variability assumptions, the Shapiro-Wilk test was performed to verify that they do not have a normality distribution for numerical variables, and for the non-parametric test, Kruscal-Wallis test was conducted to determine whether or not they are satisfied.

• The Journal of the Korea Contents Association
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• v.16 no.6
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• pp.193-204
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• 2016

The present study has the purpose of investigating the moderating effects of social support which college students may feel in the process of their emotional transfer from hopelessness to happiness. For this purpose, a survey was conducted by distributing questionnaires to 734 students enrolled in the 4-year-course colleges located in Jeollabuk-do. Frequency analysis, t-test, ANOVA, correlation analysis and hierarchial regression analysis were performed to process the data collected from questionnaires. Major outcomes of the analyses could be summed up as follows: First, hopelessness turned out to reduce happiness. Second, from the hierarchial regression analysis in which happiness was set as a dependent variable and hopelessness and social support were input gradually, it was learned that hopelessness affected happiness negatively (-) while social support exercised impact in the positive (+) direction as hopelessness had influence on happiness. Based on the results of the study, practical and political implications were discussed with a view to prepare positive mechanism such as promotion of college students' mental health and social support.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.12
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• pp.6146-6154
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• 2013

This study examined the status on job satisfaction and job performance of Advanced Practice Nurses (APNs) in Korea. The data was obtained from the 2009 APNs' job satisfaction survey of 452 nurses who received the certificate of APN between 2005 and 2008 conducted by the Korean Accreditation Board of Nursing Education. ANOVA and t-test analyses using SPSS version 14.0 were performed. The average job satisfaction level of the APNs was 2.94 out of 5.00. APNs who were performing jobs as a certified APN had a higher level of job satisfaction (t=.23, p<.001), higher wages (t=2.23, p<.05), promotion in rank (t=2.56, p<.05), more professional job performance (t=10.52, p<.001), greatest trust in their bosses and coworkers (t=5.31, p<.001), and higher confidence in their job performance (t=5.07, p<.001) than those who were not. The government and the nursing community need to provide the APNs' with the appropriate supply and demand polices, as well as a proper incentive system and job improvement.

• The Journal of the Korea Contents Association
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• v.9 no.10
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• pp.176-185
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• 2009

The study surveyed 653 people who have been blood pressure measuring and body feature in postmenopausal women received BMD test. The statistical analysis was done using the SPSS 12.0 for windows and the study using comparison analyzed at ANOVA, X 2. linear regression analysis, the following conclusions were made. As a result of analyzing the relationship between BMD and Cardiovascular Risk Factor were found to be a positive significant component(p<0.001) height, weight, BMI. After the analyses of the age, systolic blood pressure, diastolic blood pressure, total cholesterol, high density lipoprotein cholesterol, triglyceride and glucose were shown to be a negative significant component(p<0.001). Weight was the one that was mostly affected BMD(18.7%). As a result of analyzing the relationship between BMD and Cardiovascular Risk Factor had a significant component at all. According to the problem with osteoporosis in women is becoming a major issue in society. The study is considered to be tried to make phased and, better organized to establish preventive strategies and warranted causes of osteoporosis.

• Journal of Acupuncture Research
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• v.25 no.1
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• pp.187-197
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• 2008

Objectives : The purpose of this study was to assess the reproducibility of measurement of facial skin furrows using a facial skin photographing system. Methods : Subjects were 19 patients who visited the department of acupuncture and moxsibustion, at the hospital of Oriental medical college, at Daegu Haany University for the cosmetic acupuncture treatment during August 2007 to 31th August 2007. The facial skin photograph of each participant was analyzed a total of six times in two days using DM-3(a facial skin photographing system). The square and counts of skin furrows were also measured for each one. As the statistical method, Pearson's correlation coefficient and repeated measured ANOVA were used. Results : The Pearson's correlation coefficient, it showed significantly high correlation in both the square and count of skin furrows for each analysis time. Repeated measured ANOVA showed no significant differences among analyses in both square and count of skin furrows. Conclusions : This study reveales that the measurement of the count and square of facial skin furrows by facial skin photograph analysis has high reproducibility. DM-3(a facial skin photographing system) can be useful for the evaluation of facial skin furrows in facial cosmetic acupuncture.

• The Journal of Advanced Prosthodontics
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• v.10 no.3
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• pp.252-258
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• 2018

PURPOSE. The purpose of this study was to evaluate the repeatability and matching accuracy between two identical intraoral spectrophotometers. MATERIALS AND METHODS. The maxillary right central incisor, canine, and mandibular left central incisor of each of 30 patients were measured using 2 identical intraoral spectrophotometers with different serial numbers (EasyShade V). The color of each shade tab from 3 shade guides (VITA 3D-Master) was also determined with both devices. All measurements were performed by a single operator. Statistical analyses were performed to verify the repeatability, accuracy, and the differences between the devices with paired t-tests, one-way ANOVA, and intra-class correlation coefficients (ICCs) (${\alpha}=.05$). RESULTS. A high level of measurement repeatability (ICC>0.90) among $L^*$, $a^*$, and $b^*$ color components was observed within and between devices (P<.001). Intra-device matching agreement rates were 80.00% and 81.11%, respectively, while inter-device matching agreement rate was 51.85%. ANOVA revealed no significant different color values within each device, while paired t-test provided significant different color values between both devices. The CIEDE2000 color differences between both devices were $2.28{\pm}1.61$ ${\Delta}E_{00}$ for in-vivo readings. Regarding the clinical matching accuracy of both devices, ${\Delta}E_{00}$ values between teeth and matching shade tabs were $3.05{\pm}1.19$ and $2.86{\pm}1.02$, respectively. CONCLUSION. Although two EasyShade V devices with different serial numbers show high repeatability of CIE $L^*$, $a^*$, and $b^*$ measurements, they could provide different color values and shade for the same tooth.

• Korean Journal of Child Studies
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• v.26 no.6
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• pp.217-236
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• 2005

The purpose of this study was to investigate whether preschoolers' peer interaction type and level differ depending on pair compositon and task type. Preschoolers' peer interaction type and level were compared among three kinds of pair compositions(with a Younger peer, with a same-age peer, and with an older peer) as well as between two types of tasks(tasks involving real objects, and tasks involving pictures). Subjects were seventy-eight four-year-old children recruited from six child-care centers in Seoul and Gyeonggi Province. The preschoolers were randomly assigned to one of the three kinds of pair compositions. Interaction processes of the pairs were recorded by a video camera, and the scenes were transcribed for content analyses. The traniscribed peer interactions were coded according to the categories that the researcher had generated. Statistical methods used for the data analysis were frequencies, percentiles, means, standard deviations, repeated measures ANOVA, paired t-tests, one-way ANOVA. Major findings of this study were as follows: There were significant differences preschoolers' in interaction type depending on the pair compositions and the types of tasks. The preschoolers paired with the older peer used abstract collaborative explanations more frequently than in two other types of pair composition. The preschoolers paired with the younger peer used explanations without collaboration and parallel behaviors more frequently than in two other types of pair composition.

• The korean journal of orthodontics
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• v.45 no.1
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• pp.29-37
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• 2015

Objective: The coefficients of friction (COFs) of aesthetic ceramic and stainless steel brackets used in conjunction with stainless steel archwires were investigated using a modified linear tribometer and special computer software, and the effects of the bracket slot size (0.018 inches [in] or 0.022 in) and materials (ceramic or metal) on the COF were determined. Methods: Four types of ceramic (one with a stainless steel slot) and one conventional stainless steel bracket were tested with two types of archwire sizes: a $0.017{\times}0.025$-in wire in the 0.018-in slots and a $0.019{\times}0.025$-in wire in the 0.022-in slot brackets. For pairwise comparisons between the 0.018-in and 0.022-in slot sizes in the same bracket, an independent sample t-test was used. One-way and two-way analysis of variance (ANOVA) and Tukey's post-hoc test at the 95% confidence level (${\alpha}$ = 0.05) were also used for statistical analyses. Results: There were significant differences between the 0.022-in and 0.018-in slot sizes for the same brand of bracket. ANOVA also showed that both slot size and bracket slot material had significant effects on COF values (p < 0.001). The ceramic bracket with a 0.022-in stainless steel slot showed the lowest mean COF (${\mu}$ = 0.18), followed by the conventional stainless steel bracket with a 0.022-in slot (${\mu}$ = 0.21). The monocrystalline alumina ceramic bracket with a 0.018-in slot had the highest COF (${\mu}$ = 0.85). Conclusions: Brackets with stainless steel slots exhibit lower COFs than ceramic slot brackets. All brackets show lower COFs as the slot size increases.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.11
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• pp.5627-5635
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• 2013

The purpose of this study was to determine factors of women's satisfaction of hospital environment following childbirth. Data were collected using a structured questionnaire from 783 women visited at 101 hospitals for delivery and frequencies, t-test, ANOVA, Pearson's correlation, and multiple regression analyses were performed. Women's satisfaction was significantly related with personal and environmental factors. Specifically, a kind of patient room, using a shared room regardless of their preference, using family delivery room, planned hospitalization, gestational week at delivery, and hospital locations significantly predicted the variance of women's satisfaction. Therefore, hospital user satisfaction should be carefully understood as a consequence of interaction of person and environment and the level of satisfaction can be represented by the degree of congruency between personal and environmental characteristics. Furthermore, healthcare providers should develop strategies to reduce gaps between personal preferences/will/control and environmental situations, contributing to women's satisfaction with hospital following childbirth.

• Speech Sciences
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• v.10 no.3
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• pp.145-155
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• 2003

This study compared $F_{0}$ and the first three formants of eight Korean monophthongs produced by nine transgenders (male to female) to those of eighteen normal adults. Voice analysis was done by Praat (version 4.049). A one-way ANOVA with Tukey HSD post hoc tests were performed to determine statistical differences in $F_{0}$ and formant values obtained from transgenders, and normal male and female subjects. Results indicated that there was no significant difference in $F_{1}$ of /u/, /$\Lambda$/, and /o/, $F_{2}$ of /u/, /$\Lambda$/, and /i/ and $F_{3}$ of /u/ among the 3 groups (transgenders, normal males and normal females). However, in the comparison of transgenders vs. males, a significant difference was observed in $F_{0}$ of /o/, and $F_{2}$ of /i/, /a/, /e/, and /${\ae}$/ and $F_{3}$ of /e/. Furthermore, in the comparison of transgenders vs. females, a significant difference was also observed in $F_{0}$ of all vowels, $F_{1}$ of /i/, /$\alpha$/, /e/, /${\ae}$/, and /i/. $F_{2}$ of /i/, and /${\ae}$/, and $F_{3}$ of /i/, /$\alpha$/, /$\Lambda$/, /e/, /${\ae}$/, /i/, and /o/. Also, perceptual judgment of the transgenders' voice came out somewhat correlated strongly with their $F_{0}$ values but not much with the formant values. It was concluded that the transgenders' acoustic parameters are placed in between those of the normal males and females in. terms of fundamental and formant frequency analyses of vowels. Thus, it was assumed that those differences might stem from the transgenders' original big resonating cavities.