• Journal of IKEEE
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• v.13 no.2
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• pp.140-149
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• 2009

Traffic anomaly detection is one of important technology that should be considered in network security and administration. In this paper, we propose an abnormal traffic detection mechanism that includes traffic monitoring and traffic analysis. We develop analytical passive monitoring system called WISE-Mon which can inspect traffic behavior. We establish a criterion by analyzing the characteristics of a traffic training set. To detect abnormal traffic, we derive a hyperplane by using Fisher linear discriminant and chi-square distribution as well as the analyzed characteristics of traffic. Our mechanism can support reliable results for traffic anomaly detection and is compatible to real-time detection. In addition, since the trend of traffic can be changed as time passes, the hyperplane has to be updated periodically to reflect the changes. Accordingly, we consider the self-learning algorithm which reflects the trend of the traffic and so enables to increase the pliability of detection probability. Numerical results are presented to validate the accuracy of proposed mechanism. It shows that the proposed mechanism is reliable and relevant for traffic anomaly detection.

• The Journal of Advanced Prosthodontics
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• v.8 no.3
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• pp.229-234
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• 2016

PURPOSE. The purpose of this study was to investigate the demographic patterns of maxillofacial prosthetic treatment to identify the characteristics and geographic distribution of patients with maxillofacial prosthetics in the capital region of Korea. MATERIALS AND METHODS. This retrospective analytical multicenter study was performed by chart reviews. This study included patients who visited the department of prosthodontics at four university dental hospitals for maxillofacial prosthetic rehabilitation. Patients with facial and congenital defects or with insufficient medical data were excluded. The patients were classified into three categories based on the location of the defect. Patients' sex, age, and residential area were analyzed. Pearson's chi-square test with a significance level of 0.05 was used to analyze the variables. RESULTS. Among 540 patients with maxillofacial prosthetics, there were 284 (52.59%) male patients and 256 (47.41%) female patients. The number of the patients varied greatly by hospital. Most patients were older than 70, and the most common defect was a hard palate defect. Chi-square analysis did not identify any significant differences in sex, age, and distance to hospital for any defect group (P>.05). CONCLUSION. The results of this study indicated that there was imbalance in the distribution of patients with maxillofacial prosthetic among the hospitals in the capital region of Korea. Considerations on specialists and insurance policies for the improvement of maxillofacial prosthetics in Korea are required.

• Journal of Korea Water Resources Association
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• v.33 no.2
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• pp.263-276
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• 2000

This paper is to derive the probable rainfall depths and the probable rainfall intensity formulas for Inchon Metropolitan district. The annual maximum rainfall data from 10 min. to 6 hours have been collected from the Inchon weather station. Eleven types of probability distribution are considered to estimate probable rainfall depths for 12 different storm durations at the Inchon Metropolitan district. Three tests including Chi-square, Kolmogorov-Smimov and Cramer Von Mises with the graphical analysis are adopted to select the best probability distribution. The probable rainfall intensity formulas are then determined by the least squares method using the trial and error approach. Five types of Talbot type, Sherman type, Japanese type, Unified type I, and Unified type II are considered to determine the best type for the Inchon rainfall intensity. The root mean squared errors are computed to compare the accuracy from the derived formulas. It has been suggested that the probable rainfall intensities having Unified type I for the short term duration should be the most reliable formulas by considering the root mean squared errors and the difference between computed probable rainfall depth and estimated probable rainfall depth.

• The korean journal of orthodontics
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• v.42 no.1
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• pp.47-54
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• 2012

Objective: To determine and compare the frequency distribution of various arch shapes in ethnic Malays and Malaysian Aborigines in Peninsular Malaysia and to investigate the morphological differences of arch form between these two ethnic groups. Methods: We examined 120 ethnic Malay study models (60 maxillary, 60 mandibular) and 129 Malaysian Aboriginal study models (66 maxillary, 63 mandibular). We marked 18 buccal tips and incisor line angles on each model, and digitized them using 2-dimensional coordinate system. Dental arches were classified as square, ovoid, or tapered by printing the scanned images and superimposing Orthoform arch templates on them. Results: The most common maxillary arch shape in both ethnic groups was ovoid, as was the most common mandibular arch shape among ethnic Malay females. The rarest arch shape was square. Chi-square tests, indicated that only the distribution of the mandibular arch shape was significantly different between groups (p = 0.040). However, when compared using independent t-tests, there was no difference in the mean value of arch width between groups. Arch shape distribution was not different between genders of either ethnic group, except for the mandibular arch of ethnic Malays. Conclusions: Ethnic Malays and Malaysian Aborigines have similar dental arch dimensions and shapes.

• Water for future
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• v.20 no.2
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• pp.139-150
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• 1987

The present study is to develop the hydrologic analysis procedure for the purpose of drawing the probable isohyetal charts in Korea. In the establishment of optimal distribution types, the eleven continuous probability distribution types included the transformed variable normal distribution (Y-k method) is applied to the annual maximum rainfall depth series in each duration. The optimal selection of distribution is done by Chi-square test and Kolmogorov-Smirnov test in the eui-class interval. The application of probability distribution is checked by the fitting on four durations of annual maximum rainfall data(10 min., 60 min., 6 hrs., and 24hrs.) at four meteorological stations in Korea (Seoul, In Cheon, Bu san, and Kwang Ju). The properties in hydrologic application of the considered distribution and the hydrologic characteristics of the applied rainfall data groups are investigated from the results of this study.

• The Korean Journal of Applied Statistics
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• v.28 no.6
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• pp.1245-1255
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• 2015

In this paper, we investigated the major 8 companies of Korean stock market, and carried out the goodness of fit and independence tests. We found out the distributions of absolute returns are closed to compressed exponential distribution. The parameters are dominant that 1 < ${\beta}$ < 2, followed by ${\beta}=1$(exponential distribution) and ${\beta}=2$(normal distribution). Meanwhile, we assured that most of the absolute returns for major 8 companies have relevance to each other by chi-square independence test.

• Journal of Distribution Science
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• v.22 no.3
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• pp.83-92
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• 2024

Purpose: With the rapid information distribution of sport-related SNS, sport industry has utilized SNS as technical solution to distribute sport and health-related information. The current study examined the effect of SNS information use for running-specific content on running engagement and psychological well-being. Research design, data and methodology: Data were collected via online survey of participants in marathon events of United States. Descriptive statistics and Chi-square test were conducted to compare demographics and psycho-behavioral outcomes among SNS information users and non-users for running-specific contents. Multivariate hierarchical regression was next employed to examine research hypotheses. Results: A mass-participant running event was used to test seven hypotheses related to the potential role of SNS for running content in promoting running engagement and life satisfaction. In general, findings revealed that use of SNS for running content along with frequency of use can perhaps facilitate running intensity and influence participation in running-related outdoor activities. Furthermore, while overall life satisfaction did not appear to be influenced by use of SNS for running content, there was a demonstrated influence on the individual satisfaction domains. Conclusions: The findings of current study suggest that sport SNS is information distribution media enhancing users' engagement and their six life satisfaction domains. Further implications were discussed.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• v.29 no.1
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• pp.245-251
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• 2005

When we design coastal and harbol facilities deepwater design wave and wind speed are the important design parameters. Especially, the analysis of these informations is a vital step for the point of disaster prevention. In this study, we made and an extreme value analysis using a series of deep water significant wave data arranged in the 16 direction and supplied by KORDI real-time wave information system ,and the wind data gained from Wan-Do whether Station 1978-2003. The probability distributions considered in this characteristic analysis were the Weibull, the Gumbel, the Log-Pearson Type III, the Normal, the Lognormal, and the Gamma distribution. The parameter for each distribution was estimated by three methods, i.e. the method of moments, the maximum likelihood, and the method of probability weight moments. Furthermore, probability distributions for the extreme data had been selected by using Chi-square and Kolmogorov-Smirnov test within significant level of 5%, i,e. 95% reliance level. From this study we found that Gumbel distribution is the most proper model for the deep water design wave height off the southwest coast of Korea. However the result shows that the proper distribution made for the selected site is varied in each extreme data set.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.12
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• pp.389-395
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• 2020

Earnings management is a matter of concern for organizations because it affects the interests of stakeholders. This reduces the quality of information on financial statements of the organizations when the organization performs earnings management behavior. The objective of the article is to examine the impact of corporate governance on earnings management of all Vietnamese listed banks from 2015 to 2019. The article uses time-series data and ordinary least square (OLS) with Eviews 10.0 software to test the regression model. The agency and asymmetry information theory is used to explain the relationship between corporate governance and earnings management. The study results show that two variables - the foreign members of the board of directors and audit committee - have an opposite effect on earnings management behavior of Vietnamese listed banks. Therefore, the managers of listed banks need to raise awareness to express responsibility for honest and reasonable information on the financial statements. This creates trust and credibility for stakeholders. Moreover, Central bank of Vietnam should monitor regularly and enforce strict sanctions to limit earnings management behavior of listed banks. This contributes to improving the quality of accounting information in the Vietnamese banking sector to meet the trend of international economic integration.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.3
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• pp.223-233
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• 2020

The paper aims to examine the relationship of emotional intelligence on the project success, the causal relationship between emotional intelligence and project success, and also investigate the influence of emotional intelligence and the mediating role of transformational leadership as well as the moderating effect of organization commitment on the relationship between emotional intelligence and project success. Cross sessional research is applied to collect the data in this study. By applying quantitative research and survey question, the study collects 325 respondents who are the project managers. Snow-ball sampling method is used to distribute the questionnaires by face to face survey (68% of respondents) and online survey (32% of respondents). The collected data is analyzing by applying partial least square (PLS-SEM) via software SmartPLS 3.0.The result shows that the emotional intelligence and the transformational leadership making the project even more successful as the mediation actor. Furthermore, the project commitment also has the moderator effect between transformational leadership and project success. With the result of study, project managers should be aware of the importance of emotional intelligence and their commitment to the ability to manage projects successfully. A successful project is a combination of many actors, the most critical actor is the leader of the project.