• The Korean Journal of Applied Statistics
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• v.36 no.2
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• pp.129-139
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• 2023

Forecasting volatility is essential to avoiding the risk caused by the uncertainties of an financial asset. Complicated financial volatility features such as ambiguity between non-stationarity and stationarity, asymmetry, long-memory, sudden fairly large values like outliers bring great challenges to volatility forecasts. In order to address such complicated features implicity, we consider machine leaning models such as LSTM (1997) and GRU (2014), which are known to be suitable for existing time series forecasting. However, there are the problems of vanishing gradients, of enormous amount of computation, and of a huge memory. To solve these problems, a causal temporal convolutional network (TCN) model, an advanced form of 1D CNN, is also applied. It is confirmed that the overall forecasting power of TCN model is higher than that of the RNN models in forecasting VIX, VXD, and VXN, the daily volatility indices of S&P 500, DJIA, Nasdaq, respectively.

• Advances in materials Research
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• v.13 no.4
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• pp.299-319
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• 2024

Due to higher strength-to-weight ratio of composite laminates, they find uses in many weight-sensitive applications like aerospace, automobile and marine structures. From a reliability point of view, accurate prediction of failure of these structures is important. Due to the complexities in the manufacturing processes of composite laminates, there is a variation in the material properties and geometric parameters. Hence stochastic aspects are important while designing the composite laminates. Many existing works of composite laminate failure analysis are based on the deterministic approach but it is important to consider the randomness in the material properties, geometry and loading to predict accurate failure loads. In this paper the statistics of the ultimate failure load of the [0/θ]_s laminated composite plate (LCP) containing the edge crack and voids subjected to the tensile loading are presented in terms of the mean and coefficient of variance (COV). The objective is to better the efficacy of laminate failure by predicting the statistics of the ultimate failure load of LCP with random material, geometric and loading parameters. The stochastic analysis is done by using the extended finite element method (XFEM) combined with the second-order perturbation technique (SOPT). The ultimate failure load of the LCP is obtained by ply-by-ply failure analysis using the ply discount method combined with the Tsai-Wu failure criterion. The aim is to know the effect of the stacking sequence, crack length, crack angle, location of voids and number of voids on the mean and corresponding COV of the ultimate failure load of LCP is investigated. The results of the ultimate failure load obtained by the present method are in good agreement with the existing experimental and numerical results. It is observed that [0/θ]_s LCPs are very sensitive to the randomness in the crack length, applied load, transverse tensile strength of the laminate and modulus of elasticity of the material, so precise control of these parameters is important. The novelty of the present study is, the stochastic implementation in XFEM for the failure prediction of LCPs containing crack and voids.

• The Korean Journal of Rehabilitation Nursing
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• v.4 no.2
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• pp.137-145
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• 2001

This study examined and identified the relationship between the level of hope and self-care agency in hemodialysis patients. The purpose of the study was to reveal that hope is an essential factor to enhance self-care agency and to prepare the basic materials to help nurse the patients. The subjects for this study consisted of 108 persons who undergoing hemodialysis from 2 hospital, 2 hemodialysis center in Pusan, Korea. The degree of hope was measured by the questionnaire that has been developed by Miller. The self-care agency was measured by the questionnaire that has been developed by Kearney B.Y & Fleisher B.J. The collected data were analyzed by descriptive statistics and t-test. one-way ANOVA and Pearson's Correlation Coefficient with SPSS WIN program. Results were obtained as follows: 1) The mean scores of hope were $131.77{\pm}25.77$(range 67-195). The rate of hope classified said that the lowest hope was 2.8% and low hope was 27.8%. 2) The mean scores of self-care agency were $143.78{\pm}23.63$(range 74-187). The degree of self-care agency classified said that the rate of self-care agency deficiency was 0.9% and low self-care agency was 12.0%. 3) The hope was significantly related to self-care agency. That is, the higher the hope score was， the higher the level of self-care agency score(r=0.668，p=0.001) was. In this result, there were hemodialysis patients who have very low hope score and self-care agency score. In this cases self-care agency can be increased by encouraging the patients to be more hopeful. Conclusively nurses should access the degree of hope and self-care agency of hemodialysis patients individually and apply the hope therapy in order that the patient have higher hope than before.

• Journal of dental hygiene science
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• v.17 no.3
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• pp.242-249
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• 2017

The purpose of this study was to investigate the level of cultural competence and its influencing factors among 530 dental hygiene students. The analysis was performed using PASW Statistics ver. 18.0, and the following conclusions were drawn. Cultural knowledge levels showed a significant difference according to general characteristics in four components of cultural competence levels. Cultural competence and its four components were higher in subjects who have a religion (p<0.05). The differences in cultural competence levels according to culture-related characteristics are as follows. In individuals with experience of taking foreign culture-related classes, intention to work overseas, or fluency in a foreign language, cultural competence levels and its four components such as cultural comfort, knowledge, awareness, and behavior intent were higher (p<0.05). Intention of overseas employment was the factor most strongly influencing the level of cultural competence of the subjects. The more intention the subjects have to work overseas, the more they have experienced foreign culture-related lessons, the more fluently they speak a foreign language, and the higher level of cultural competency they reached (p<0.05). As the research results show, it is necessary to establish a continuing plan to understand and communicate with individuals of other cultures through foreign language and foreign culture classes in schools in order to improve the level of cultural competence. This education would reduce the fear and stress that subjects might make a mistake in meeting with people from other cultures, and it could be a preparatory process to actively carry out dental hygiene practice with foreigners.

• Journal of Convergence for Information Technology
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• v.11 no.3
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• pp.34-45
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• 2021

The purpose of this study was to investigate the major selection motivation, academic stress, self-efficacy and college life adjustment and identify influencing factors of college life adjustment in the crisis situation of COVID-19. 243 nursing students were selected from 2 regions through convenience sampling. Data were analyzed through descriptive statistics, t-test, ANOVA, Scheffé test, Pearson's correlation coefficients and multiple linear regression analysis using SPSS for Windows Ver. 22.0. The higher the major selection motivation and self-efficacy, the higher the college life adjustment. The lower the academic stress, the higher the college life adjustment. The factors influencing college life adjustment were self-efficacy, major selection motivation, monthly allowance, and the explanatory power of these variables for college life adjustment was 65.6%. Therefore, in order to improve the nursing students' college life adjustment, it is necessary to develop and apply college life adjustment program to increase self-efficacy.

• Journal of East-West Nursing Research
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• v.29 no.2
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• pp.129-140
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• 2023

Objectives: Suicide rate in South Korea is one of the major public health concerns. This study examined the factors influencing the suicide methods of people who committed suicide in Gyeonggi-do, which accounts for one-fourth of the population of South Korea. Methods: This study analyzed the data of a total of 13,945 suicide deaths in Gyeonggi-do over a five-year period (2016-2020) provided by the Statistics Korea and the influence of social and demographic characteristics on the analyzed suicide methods. The differences in suicide methods according to the social and demographic characteristics of suicide victims were compared and analyzed through chi-squared, and items with significant differences in univariate tests were analyzed by multiple logisitic regression analysis. Results: Among suicide deaths, the most common method of suicide was hanging (52.4%). In particular, women, were employed, and stayed at home were higher risk of being hanged. The second most common method of suicide was leaping (17.7%). Women under the age of 30, those with a college degree or higher, those who were not working, time of death (6-12), and those outside the home were more likely to choose to take the leap. The third most common method of suicide was gas poisoning (15.8%). Young people under the age of 65, college graduates or higher, without a spouse, were employed, and spring season were at increased risk of choosing gas poisoning. Conclusions: The results highlight the need for policies that consider risk factors such as gender, age, education, marital status, employments status, time of suicide, and place of suicide in order to block access to suicide methods for suicide victims in Gyeonggi-do.

• Korean Journal of Oriental Medicine
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• v.14 no.2
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• pp.47-66
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• 2008

Background: It is insufficient information that are syndrome differentiations and detail symptoms in Korean. Methods: 19 traditional korean medical agencies collected 190 cases with vital sign, body measurement, patient own symptoms report and doctor diagnosis. And then we analyzed general distributions and comparisons of deficiency and non-deficiency. Results: The most past histories, in order, were the arthritis(20%), gastroenteropathy, hypertension, anemia, diabete mellitus. In chief complains, musculoskeletal occupies 60 percent of the total, and digestive system, head in order. In the syndrome differentiation, it appeared deficiency, spleen, Qi deficiency in order. Age(p=0.000), systolic blood pressure(p=0.044) and the waist-hip ratio(p=0.000) was significantly higher in the deficiency group compared with non-deficiency group. Patients with condition which dislikes the wind and with anxiety and with amazing and fear(驚恐) were significantly more in deficiency group(p=0.029, p=0.017, p=0.044). Conclusions: These statistics are continually revised report and it will be reported comparison of several syndrome differentiations and therapeutic effects by treatment methods.

• The Journal of the Korean dental association
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• v.51 no.7
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• pp.405-413
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• 2013

Pediatric and adolescent dental anxiety and fear have been researched in the connection with behavior modification for a long time and this dental anxiety can persist until the adult hoods resulting in extreme fear of and avoidance of dental treatments and causes oral health deterioration. However, the domestic researches regarding adolescent dental anxiety and fear are insufficient. For this reason, this study aims to examine the level of fear and the influential factors affecting their dental fear and to utilize the result as the basic materials in the dental management. The subjects were the students from a middle school located in Gyeonggi-Do. The school was selected by convenient sampling and self-answered questionnaire was filled in by the students. The distribution of responses in each category of fear was examined by frequency analysis. The analysis was conducted using cross tabulation in order to examine the difference between male students and female students and using independent sample t-test in order to compare the fear score of each category. The study results showed the fear score of female students for the category 'causing irritation during the dental treatments' was significantly higher in statistics(p<0.05). Therefore, these results should be reflected to the dental care environments in order for the adolescent to reduce the dental anxiety and fear.

• Journal of Korean Academy of Nursing
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• v.10 no.2
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• pp.95-115
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• 1980

Current statistics reveal remarkable prolongation of the average longevity in this country for the past decade. Welfare of the aged is no longer sole concern of the person or/and family. but has aroused social concern on the community and national level. This study was designed to assess social, economic and emotional needs of the aged. and to identify problems they are confronting. Data were gathered through questioning 273 subjects living in Seoul from July 25, to August 31. 19 80. Frequencies and percentile scores were analysed to describe the fact. and the significance of int or-variable differences was tested by Chi-square method. Results are : 1. Majority of the subjects (male : 65.38%). (female : 62.13%)“talk about past experiences”to re-collect their past days, the difference between male and female respondents was not significant. 2. Except few who earn their pocket money (4.21%). majority were doing household errands (34.52% ) and looking after their garnd children (29.26 ％）. Main sources of their pocket money revealed to be their children (84.02%) and their own savings (24.64% ). Except few (15％）engaged with social activities directly or indirectly. leisure hours are spent in chatting with aged neighbors (44.81%). Highest in the rank order on the joyous moments for the aged revealed to be when the members of family living apart paying a visit (male : 37.5%, female : 63.72%)difference of male and female was significant ( P<0.05). Among female respondents. significant difference between age group was revealed (p<0.05). 3. Majority prefered sin91e houses (84.30% ). as residential environment. the suburban (36.26% ) area was the filet in the rank order : difference between age group and the educational status were not significant. Majority of respondents revealed to have their own room in the house. The first preference was given to live with their children (68.86%). Memory of the past (37.36% )revealed to be the highest in the rank order among the reasons why they dislike moving the house. 4. Majority favored current welfare benefts provided for the old age. however. the ideal way to live at their old age they responded was to live on their own savings (50.54%). 5. Majority revealed to be daunted occasionally (62.27%) by not being less active (34.16%) socially and by poor physical health(29.75%). Male and female differ in the causes of loneliness significantly (P <0.001) : retirement (37.89%) in ale and helpessness (43.05%) in female revealed the highest in the rank order. Majority talk over their feelings with aged neighbors to overcome the loneliness. 6 Majority were in favor of planting and looking after pet animal in the house. however. male and female differ in the kind significantly (p <0.001), 7. Majority think about death and dying occasionally or more (84.11% ). Many of the respondents believes in the life after life (53.49%) : female revealed to be significantly higher (p <0.01). and subjects with christian belief were significantly higher than non-christians (P<0.001). Attitude towards death and dying differs significantly between male and female (P <0. 001) and between christians ans and nonchristians (p <0.001). Highest preference was given to simple funeral (69.85%). Precious heritage that they would pass on to their descendants was onoscience and ethical value(57. 51%) : christian response as the first value was christian belief (52.38%).

• Korean Journal of Health Education and Promotion
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• v.31 no.3
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• pp.1-13
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• 2014

Objectives: This study was performed to identify factors related to perceived health status among patients with type 2 diabetes. Methods: This is cross-sectional observational study. Respondents were 106 visitors in an outpatient diabetes clinic of a university hospital. Self-report questionnaire which included general information inquiry, diabetes-related, sociopsychological factors, functional health literacy and perceived health status was used for this study. The data was analyzed by using descriptive statistics, independent simple t-test, one-way ANOVA, and hierarchical multiple linear regression. All analysis were conducted using SAS 9.3. Results: Among the respondents, 43.4% engaged in poorly perceived health status. After adjusting for control variables, functional health literacy is significantly related to perceived health status(${\beta}$=0.095, p=0.016). Conclusion: Independent of diabetes-related, sociopsychological factors, higher functional health literacy is associated with better perceived health status of patients with type 2 diabetes. In order to improve perceived health status in the type 2 diabetes patients, it is necessary to develop strategy to enhance the functional health literacy.