• The Korean Journal of Applied Statistics
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• v.22 no.5
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• pp.1073-1084
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• 2009

For ordinal categorical $R{\times}R$ tables, a weighted measure of association, $H_{\omega}$, was proposed and its maximum likelihood estimator and asymptotic variance were drived. We redefined the last paradox of ${\kappa}$ and proved its relation to marginal distributions. We also introduced the new paradox of ${\kappa}$ and summaried the general relationships between ${\kappa}$ and marginal distributions.

• Journal of the Korean Data and Information Science Society
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• v.26 no.1
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• pp.77-87
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• 2015

Parrondo paradox is the counter-intuitive phenomenon where two losing games can be combined to win or two winning games can be combined to lose. In this paper, we consider an ensemble of players, one of whom is chosen randomly to play game A' or game B. In game A', the randomly chosen player transfers one unit of his capital to another randomly selected player. In game B, the player plays the history-dependent Parrondo game in which the winning probability of the present trial depends on the results of the last two trials in the past. We show that Parrondo paradox exists in this redistribution model of the history-dependent Parrondo game.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.12 no.10
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• pp.5143-5158
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• 2018

Improving the intrusion detection system (IDS) is a pressing need for cyber security world. With the growth of computer networks, there are constantly daily new attacks. Machine Learning (ML) is one of the most important fields which have great contribution to address the intrusion detection issues. One of these issues relates to the imbalance of the diverse classes of network traffic. Accuracy paradox is a result of training ML algorithm with imbalanced classes. Most of the previous efforts concern improving the overall accuracy of these models which is truly important. However, even they improved the total accuracy of the system; it fell in the accuracy paradox. The seriousness of the threat caused by the minor classes and the pitfalls of the previous efforts to address this issue is the motive for this work. In this paper, we consolidated stratified sampling, cost function and weighted Support Vector Machine (WSVM) method to address the accuracy paradox of ID problem. This model achieved good results of total accuracy and superior results in the small classes like the User-To-Remote and Remote-To-Local attacks using the improved version of the benchmark dataset KDDCup99 which is called NSL-KDD.

• International Journal of Fluid Machinery and Systems
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• v.10 no.1
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• pp.47-53
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• 2017

Surface pressure integration and momentum method were respectively performed to evaluate the impeller thrust and the system thrust of a contra-rotating axial flow water jet propulsion, and an interesting phenomenon so-called thrust paradox was revealed. To explain the paradox, the impeller thrust and the system thrust were physically and theoretically analyzed, the results show that the impeller thrust is head involved and is determined by the hydraulic parameters upstream and downstream the impeller, while the momentum method depicted by a classic equation is valid simply under the best efficiency point. Consequently, the role of a water jet propulsion nozzle was deduced that the nozzle is mainly to limit the flow rate that crosses the impeller and to assure the system working under the best efficiency condition apart from its ability to produce momentum difference. Related mathematical formula expressed the nozzle diameter is the dominant variable used to calculate the working condition of the water jet propulsion. Therefore the nozzle diameter can be steadily estimated by the former expression. The system thrust scaling characteristics under various speeds were displayed lastly.

• Journal of the Korean Data and Information Science Society
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• v.27 no.5
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• pp.1241-1251
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• 2016

We consider a correlated discrete-time random walk in which the current jump size depends on the previous jump size and a noncorrelated discrete-time random walk where the jump size is determined independently. By using the strong law of large numbers of Markov chains we derive the formula for the asymptotic means of the random mixture and the periodic pattern of these two random walks and then we show that there exists Parrondo's paradox where each random walk has mean 0 but their random mixture and periodic pattern have negative or positive means. We describe the parameter sets at which Parrondo's paradox holds in each case.

• Korean Journal of Logic
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• v.22 no.1
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• pp.87-124
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• 2019

A dialetheic approach to the sorites paradox is to understand a borderline case as a true contradiction. In order to accommodate this approach, the possibility of an alternative that does not involve a contradiction should be considered first. Beall presents an alternative that has all virtues of dialetheic solution without contradiction. I do not think his alternative has no contradiction. Using the inclosure schema I will show it. Furthermore, I will show that all alternatives which do not accept the existence of cut-off point imply a contradiction. This means that we have to accept a true contradiction as long as we accept the intuition of vagueness, especially, what is called 'tolerance'.

• Korean Journal of Schizophrenia Research
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• v.22 no.2
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• pp.56-65
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• 2019

Objectives: The primary objective was to test the phenomenon known as the insight paradox, which refers to the association between higher levels of insight and lower self-esteem, higher hopelessness, and a higher perception of social prejudice among patients with schizophrenia. Methods: A total of 216 outpatients with schizophrenia according to the DSM-IV diagnostic criteria were recruited. All participants were receiving ongoing outpatient treatment and were in a stable phase of the disorder. The participants were divided into a good-insight (N=109) and a poor-insight (N=107) group by the direct interview and the mean score of questionnaire. The parameters used for analysis and comparison were demographic variables (age, gender, education), clinical variables (age at onset, number of hospitalizations), self-esteem, hopelessness, self-stigma, and quality of life. Results: Compared with the poor-insight group, the good-insight group was found to have a lower number of hospitalizations, lower self-esteem, higher hopelessness, lower quality of life, and a higher level of internalized stigma. Conclusion: The insight can cause the negative consequences in patients with schizophrenia. Therefore, clinicians should pay attention to the negative aspects of insight for improving the quality of life in the treatment of patients with schizophrenia.

• Asia pacific journal of information systems
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• v.30 no.4
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• pp.919-945
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• 2020

Social media platforms such as Instagram and Facebook lead to potential security risks, which consequently raise public concerns about privacy. However, most people rarely make active efforts to protect their personal data, even though they have shown increasing concerns about privacy. Therefore, this study examines the factors that determine social media users' behavior of using privacy settings and testifies the existence of privacy paradox in such a context. In addition, it investigates the mediating effects of implementation intentions on the relationship between intentions and behaviors. In the study, we collected data through questionnaires, and the respondents were undergraduate and graduate students in South Korea. After a pilot test (n = 92) and a set of face-to-face interviews, 266 usable responses were retrieved for data analysis finally. The results confirmed the existence of the privacy paradox regarding the use of social media privacy settings. And the implication intention did positively mediate the relationship between intention and behavior in the context of social media privacy settings. To the best of our knowledge, our study is the first in the information privacy literature to introduce the notion of implementation intention which is a much more powerful explanation and prediction of actual behavior than the (behavioral) intention.

• Proceedings of the Korean Society for History of Mathematics Conference
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• 2001.11a
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• pp.9-9
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• 2001

• The Mathematical Education
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• v.32 no.2
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• pp.101-105
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• 1993