• Maxillofacial Plastic and Reconstructive Surgery
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• v.36 no.1
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• pp.1-6
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• 2014

Purpose: This study was designed for identification of the main clinicopathological features of cysts in the oral and maxillofacial regions. Methods: A retrospective observational study was conducted on 164 patients who had been diagnosed with cyst of the jaw, from the database of 168 histopathological diagnoses at the Department of Oral and Maxillofacial Surgery of Busan Paik Hospital at Inje University, from January 2009 to December 2011. The subjects were treated and the following variables were recorded: gender, age, clinical signs and symptoms, histopathological distribution, treatment methods, and complications. A descriptive analysis of the study variables was performed using a chi-square test. Results: Among the 164 patients, there were more male than female patients (male-female ratio: 1.7:1). The most predominant ages were the 20s and 40s. Among the classes of pathological cysts, radicular cysts and dentigerous cysts were the most common, with incidences of 56.0% and 35.1%. Thirty-six percent of the patients had no symptoms; and of those who had symptoms, the main signs and symptoms were swelling (24.4%) and pain (17.1%). The most frequent management method was the combination operation, such as enucleation with or without extraction and apicoectomy of the causative teeth. Of the 164 patients, 13 had complications; and one patient who had been treated with enucleation with apicoectomy had a recurrent cyst. Conclusion: Using a chi-square test, no significant differences in prevalence were observed in relation to gender according to age. Comparative analysis of radicular and dentigerous cysts showed a significant difference in their prevalence according to their anatomical location, however, no significant differences in were observed in their incidence rates according to age.

• Journal of Technology Innovation
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• v.21 no.2
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• pp.285-317
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• 2013

This paper delineates dynamic capabilities, which can be measured by internal capability and external knowledge, and also, in the shape of dynamic capabilities, bases on that corporate actions are expatiated by fitness and rent of evolutionary perspective. To achieve the goal of this study, classifying types of Nano-technology enterprise and suggesting analytical pattern based on dynamic capabilities, this thesis substantially analyzes how to categorize a type of enterprise and gauge a result through a survey of 359 domestic companies producing goods concerned with Nano-technology. This paper analyzes whether or not the internal capability and external knowledge affect the outcome of a certain enterprise. Moreover, in according to the results of practical analysis, it deducts 2 new variables by applying principal component analysis on four previous variables showing the internal capability and external knowledge. By classifying four types of enterprises with criterion of these two factors based on a relative extent and comparing each typical financial result, this paper suggests that the companies with relatively higher level of the internal capability and external knowledge surpass the lower ones at the financial outcome. Not only this, but also the technology-level analysis shows the same result, the higher capability and knowledge the higher performance. However, the analysis based on the difference of the four types of financial outcomes reveals that technological and evolutionary fitness can determine financial achievement.

• International Area Studies Review
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• v.22 no.3
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• pp.29-66
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• 2018

The purpose of the study was to point out the limitation of the conceptual discussions in which researches on gender responsive budgeting have remained so far and to empirically analyze the effect of institutionalization of gender responsive budgeting on the gender equality by using macro data. The units of the analysis were 73 countries which implements gender responsive budgeting among the 229 countries registered in the World Bank. Panel data were established on the materials of 7-year period from 2006 to 2012, which were analyzed by Fixed Effect Model. Gender Equality (Gender Gap Index) which is the ultimate goal of gender budgeting was established as the dependent variable while Institutionalization of Gender Responsive Budgeting (formal and qualitative classification) was established as the independent variable. In addition, social and economic factors, political factors and geographical factors which were judged to affect dependent variables were established as control variables. As a result of analysis, the institutionalization of gender responsive budgeting has positive effect on gender equality. Thus, the study confirmed that gender responsive budgeting has positive effect on gender equality in countries with legal, procedural and formal foundations rather than in countries with simple rhetoric in catchwords and documents. Moreover, the higher the level of institutionalization of gender responsive budgeting is, the more positive effect it has on the gender equality. Therefore, the study found out that efforts need to be accompanied to enhance the level of institutionalization in order to increase the effectiveness of institutionalization of gender responsive budgeting.

• Journal of Korean Medicine for Obesity Research
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• v.13 no.1
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• pp.33-45
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• 2013

Objectives: This study was aimed to find out the characteristics of ordinary symptoms between the control and patient groups, diagnosed as overweight or obesity, in Soyang, Taeeum, and Soeum Constitutions and among those 3 groups. Methods: As a prospective cross-sectional study based on medical records, 9213 patients, who visited Kyung Hee University Medical Center from May in 2007 to June in 2010, were included. To diagnose the constitution, Revised Questionnaire for the Sasang Constitution Classification II and examinations by oriental medical doctors who majored in Sasang Constitution Medicine were performed. Based on the World Health Organization criteria for Asian obesity assessment, body mass index (BMI) was classified into 3 groups; more than 25 as obesity, 23 to 25 as overweight, and less than 23 as normal. Ordinary symptoms questionnaire, which consists of 46 questions in 8 categories, were given to the subjects. One-way ANOVA test in continuous variables and chi-square test in categorical variables were carried out to analyze statistical significance. Results and Conclusions: 1) In general characteristics, we could find out the significant differences in age, sex, height, weight, BMI, waist circumference, blood pressure, total cholesterol, triglyceride, low density lipoprotein cholesterol, high density lipoprotein cholesterol, fasting blood sugar, and hemoglobin A1c among the 3 Constitutional groups. 2) Soyang Constitution of overweight and obesity has tendency to have higher appetite, like cool or cold water, defecate more, swear more, dislike heat, and have warmer or hotter extremities in the ordinary symptoms, compared with the control group. 3) Taeeum Constitution of overweight and obesity has tendency to have higher appetite, like cool or cold water, defecate more, swear more, dislike heat, and have warmer or hotter extremities in the ordinary symptoms, compared with the control group. 4) Soeum Constitution of overweight and obesity has tendency to have higher appetite and less fatigue in the ordinary symptoms, compared with the control group. 5) Soeum Constitution showed the slightest increase in appetite, preference about room temperature water, less number of feces, and feeling of chill and warmer extremities in ordinary symptoms, compared with Soyang and Taeeum Constitutions. Taeeum Constitution showed the distinct increase in appetite and sweating in ordinary symptoms, compared with Soyang and Soeum Constitutions.

• Journal of Internet Computing and Services
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• v.22 no.2
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• pp.29-39
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• 2021

As damages to individuals, private sectors, and businesses increase due to newly occurring cyber attacks, the underlying network security problem has emerged as a major problem in computer systems. Therefore, NIDS using machine learning and deep learning is being studied to improve the limitations that occur in the existing Network Intrusion Detection System. In this study, a deep learning-based NIDS model study is conducted using the Convolution Neural Network (CNN) algorithm. For the image classification-based CNN algorithm learning, a discrete algorithm for continuity variables was added in the preprocessing stage used previously, and the predicted variables were expressed in a linear relationship and converted into easy-to-interpret data. Finally, the network packet processed through the above process is mapped to a square matrix structure and converted into a pixel image. For the performance evaluation of the proposed model, NSL-KDD, a representative network packet data, was used, and accuracy, precision, recall, and f1-score were used as performance indicators. As a result of the experiment, the proposed model showed the highest performance with an accuracy of 85%, and the harmonic mean (F1-Score) of the R2L class with a small number of training samples was 71%, showing very good performance compared to other models.

• The Journal of Society for e-Business Studies
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• v.24 no.3
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• pp.35-51
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• 2019

The two main goals of this study are to derive independent factors affecting the success rate of crowdfunding and to empirically analyze the variation of independent factors' effects on the success of crowdfunding by industry (Internet, culture/art, manufacturing/distribution), and funding type (stock type, bond type). To identify the success factors of crowdfunding for invigoration and strategic utilization, first, several variables were refined after interviews with experts and platform operators with investment experiences in numerous crowdfunding projects. Then, independent factors affecting project involvement were categorized as follows: a characteristic of project, participant activity, and enterprise. Also, the results derived from the influence of independent variables on crowdfunding after moderating effects were driven. Selected independent factors in this study are as follows: crowdfunding period, target amount, visual contents, minimum account money, number of comments, number of SNS followers, level of interest, financial Statement disclosure, investment attraction, venture company, intellectual property rights disclosure, and business operation period. Selected moderating factors in this study are as follows: industry (Internet, culture/art, manufacturing/distribution), and funding type (stock type, bond type). In conclusion, a discussion of the academical and practical implications and a suggestion of directions for further research are explained.

• The Korean Journal of Applied Statistics
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• v.34 no.5
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• pp.745-760
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• 2021

Prediction of a stock price has been a subject of interest for a long time in financial markets, and thus, many studies have been conducted in various directions. As the efficient market hypothesis introduced in the 1970s acquired supports, it came to be the majority opinion that it was impossible to predict stock prices. However, recent advances in predictive models have led to new attempts to predict the future prices. Here, we summarize past studies on the price prediction by evaluation measures, and predict the direction of stock prices of Samsung Electronics, LG Chem, and NAVER by applying various machine learning models. In addition to widely used technical indicator variables, accounting indicators such as Price Earning Ratio and Price Book-value Ratio and outputs of the hidden Markov Model are used as predictors. From the results of our analysis, we conclude that no models show significantly better accuracy and it is not possible to predict the direction of stock prices with models used. Considering that the models with extra predictors show relatively high test accuracy, we may expect the possibility of a meaningful improvement in prediction accuracy if proper variables that reflect the opinions and sentiments of investors would be utilized.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.21 no.6
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• pp.132-145
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• 2022

This study was based on the black box images of traffic accidents on highways, cluster analysis and prediction model comparisons were carried out. As analysis data, vehicle driving behavior and road surface conditions that can grasp road and traffic conditions just before the accident were used as explanatory variables. Considering that traffic accident data is affected by many factors, cluster analysis reflecting data heterogeneity is used. Each cluster classified by cluster analysis was divided based on the ratio of the severity level of the accident, and then an accident prediction evaluation was performed. As a result of applying the Logit model, the accident prediction model showed excellent predictive ability when classifying groups by cluster analysis and predicting them rather than analyzing the entire data. It is judged that it is more effective to predict accidents by reflecting the characteristics of accidents by group and the severity of accidents. In addition, it was found that a collision accident during stopping such as a secondary accident and a side collision accident during lane change act as important driving behavior variables.

• Journal of Environmental Health Sciences
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• v.48 no.6
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• pp.324-330
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• 2022

Background: Lung injuries due to exposure to humidifier disinfectants (HDs) were reported in 2011 in South Korea. As a result of the government's epidemiological investigation and toxicity test study, it was found that HDs caused health damage such as lung disease. Objectives: The purpose of this study was to classify HD exposure ratings and analyze the affecting factors that could identify the relationship with lung disease. Methods: Exposure assessment for HDs was conducted using a questionnaire during face-to-face interviews with the applicants. Ratings of high exposure (Class 1) and low exposure (Class 2) were cross-tabulated with clinical ratings (acceptable and unacceptable). Logistic regression analysis was carried out by setting the clinical rating of lung disease as a dependent variable and the socio-demographic and exposure characteristics obtained through the questionnaire as independent variables. Results: The concentration in air of polyhexamethylene guanidine (PHMG) was 71.96±107.47 ㎍/m³, and the exposure concentration was 15.21±23.28 ㎍/m³ . The exposure rating was overestimated with 97.1% of affected subjects having high exposure using margin of exposure (MOE), but only 9.9% matching the clinical class. In the overestimated group, it could be explained by the fact that the exposure time was long and the subjects had already recovered from damage symptoms. As a result of logistic regression analysis, ten variables were found to be significant influencing factors. Conclusions: A new exposure rating could be calculated based on the MOE, and factors affecting lung disease could be estimated through comparative evaluation with the clinical rating.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.11
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• pp.5534-5541
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• 2012

This paper classifies cities in the metropolitan area based on natural hazard vulnerability. The procedure of our empirical analysis is divided into three parts as follows: First, it summarizes variables related to natural hazard vulnerability to significant factors, carrying out principal component analysis. Second, it classifies cities in the metropolitan area, conducting cluster analysis using factor scores. Lastly, it proposes differential measures for natural hazard mitigation for classified cities in the metropolitan area, based on natural hazard vulnerability.