• Korean Journal of Cognitive Science
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• v.27 no.1
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• pp.61-99
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• 2016

This research investigated that participants' response time and recognition in the decision-making situation would vary according to either rational or emotional stimuli and analyzed how brain functions are related to each type of stimuli by means of fMRI. We tried to address the difference of cognitive processing between rational stimuli and emotional stimuli in the perspective of information processing theory. In order to achieve the research purpose above, we conducted two kinds of experiment studies. In study 1, subjects conducted decision-making task which selected which kind of information type the stimuli was after stimuli - rational stimuli or emotional stimuli - was randomly seen during experiment. During this experiment, we investigated the effect of each stimuli by measuring the duration from the onset time at which stimuli was shown to the response time at which subjects conducted decision-making. Furthermore, we compared the brain functions by finding out what kinds of brain areas were activated during the decision-making task. In study 2, subjects conducted recognition task at which subjects made a decision whether the stimuli was sees in the previous experiment or not. During the second experiment, we investigated the recognition effect by measuring the memory for each stimuli type. Moreover, we compared the cognitive processes during recognition by analyzing the differences of brain area functions. The results of two experiments above were as following. Firstly, regarding the response time as the effect of stimuli, we found that the effect of emotional stimuli was higher than that of rational stimuli. And regarding the recognition as the effect of stimuli, it was found that the effect of rational stimuli was higher than that of emotional stimuli. Secondly, the explanation about the characteristics of cognitive processes with the result of behavioral response by analyzing brain functions was as following. First of all, regarding the decision-making task which conducted for analyzing the effect of response time, the relatively high activated brain areas of rational stimuli were related with the functions of movement control or working memory, and the relatively high activated brain areas of emotional stimuli were connected with the functions of lingual processing.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.14 no.1
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• pp.12-25
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• 2003

Objectives：As increasing number of new antidepressants have been being introduced in clinical practice, pharmacological understanding has been broadened. These changes mandate new information and theories to be incorporated into the treatment process of children with depressive disorders. In light of newly coming knowledge, this review intended to recapitulate the characteristics of new antidepressants and to consider the pivotal issues to develope guidelines for the treatment of depression in childhood and adolescence. Methods：Searching the Pub-Med online database for the articles with the key words of 'new', 'antidepressants' and 'children' ninety-seven headings of review articles were obtained. The author selected the articles of pertinent subjects in terms of either treatment guideline or psychopharmacology of new antidepressants. When required, articles about the clinical effectiveness of individual antidepressants were separatedly searched. In addition, the safety information of new antidepressants was acquired by browsing the official sites of the United States Food and Drugs Administration and Department of Health and Human Services. Results：1) For the clinical course, treatment phase, and treatment outcome, the reviews or treatment guidelines adopted the information from adult treatment guidelines. 2) Systematic and critical reviews unambiguously concluded that selective serotonin reuptake inhibitors(SSRIs) excelled tricyclic antidepressants( TCAs) for both efficacy and side effect profiles, and were recommend for the first-line choice for the treatment of children with depressive disorders. 3) New antidepressants generally lacked treatment experiences and randomized controlled clinical trials. 4) SSRIs and other new antidepressants, when used together, might result in pharmacokinetic and/or pharmacodynamic drug-to-drug interaction. 5) The difference of the clinical effectiveness of antidepressants between children and adults should be addressed from developmental aspects, which required further evidence. Conclusion：Treatment guidelines for the pharmacological treatment of childhood and adolescence depression could be constructed on the basis of clinical trial findings and practical experiences. Treatment guidelines are to best serve as the frame of reference for a clinician to make reasonable decisions for a particular therapeutic situation. In order to fulfill this role, guidelines should be updated as soon as new research data become available.

• Journal of KIISE:Computer Systems and Theory
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• v.30 no.11
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• pp.655-662
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• 2003

In some volume visualization fields such as medical imaging, anisotropic volume data are more common than isotropic ones. In this paper, we propose an efficient rendering method for anisotropic volume data, which directly computes the intensity of intermediate samples by interpolating the intensity of two corresponding voxels on consecutive slices. Unlike density interpolation method, it does not require a preprocessing step for generating intermediate slices or additional memory for storing them. Additionally, we propose an adaptive intermediate voxel insertion method that avoids overblurring on object surfaces. This may occur when we render high frequency areas using the intensity interpolation method. Using these methods, we can improve the rendering speed without sacrificing image quality.

• Journal of Korea Multimedia Society
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• v.15 no.4
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• pp.552-559
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• 2012

Operating Systems is a discipline which handles complex and concepts related to its components and how an operating system works. However, most of the OS courses have been textbook-oriented theoretical classes. Therefore, many instructors have tried to make use of educational tools to help students understand a lecture and arouse their interests consistently. This paper describes the design and implementation of a web-based page replacement simulator which shows the process of page replacement algorithms visually. The academic achievement evaluation and t-test results for 2010's students and 2011's show that the differences of the correct answer ratios for the exam about page replacement algorithms and the scores between two groups are meaningful. And the results of survey show that a page replacement simulator is useful as an educational tool which causes the interests about operating systems and enhances the understanding of a lecture.

• The Journal of the Korea Contents Association
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• v.10 no.9
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• pp.201-211
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• 2010

The aim of this study is to investigate the method to enhance user cognition for "STM information(Short-term Memorable Information)" that is relatively accessible to information in a short period of time in information design types. What stands out from this study is the design attributes and expression method of information in a broad perspective. By 4 visualization attributes of function variable; 'Operations', 'Events', 'Methods' and 'Use cases', STM information should be satisfied by the attribute of 'Understandable' and 'Accessibility' from the point of view of visual representation and by the attribute of 'Errorless' and 'Timeliness' from the point of view of user operation. As the expression method of each perspectives, I suggested "Attribution theory", "Cognitive model", "Maximization of Proactivity", "Minimization of surplus information" and "Using dual-code" in the point of view of visual representation, and "Context effect", "Using memory code" and "Two methods of information scanning" in the point of view of user operation. I assured that above-mentioned methods are efficient and cognitive pattern of user for STM information is found out by survey and interview.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.8 no.2
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• pp.217-231
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• 1997

This paper first reviewed the current neurological theories concerning the etiology of ADHD and secondly, examined results of studies that applied neuropsychological assessment methods in the examination of ADHD children both here in Korea and abroad. ADHD children were found to exhibit characteristic responses indicating deficits in vigilance, sustained attention, distractibility, allocation and regulation of attention in many assessments of attention, in addition to deficits in executive functioning, working and associative memory. Such neuropsychological assessment results suggest that in addition to dysfunction in the frontal lobe and the reticular activation system, dysfunction may exist in other neural pathways involving many areas of the brain. However, because a substantial number of neuropsychological assessment tools being employed in Korea for ADHD children had been developed abroad, a Korean standardization project involving ADHD and normal control children, in addition to other child psychiatric population pools must be conducted in order to obtain appropriate age norms and test validity, and in order to make possible a more accurate and precise comparison and interpretation in the assessment of ADHD children.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.38C no.11
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• pp.1000-1009
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• 2013

This study investigated changes in behavioral performance before and after watching a multi-view 3D content by using auditory stimuli based on the selective attention theory in order to quantitatively evaluate 3D visual fatigue. Twenty-one undergraduates were asked to report on their current visual and physical condition both in the pre- and post-experiment. A selective attention task was conducted before and after mobile 3D viewing to compare the changes in performance. After performing a Wilcoxon's matched-pairs signed-ranks test on the subjective ratings of 3D visual fatigue, participants were categorized into two groups, unfatigued and fatigued group with a definite criterion. For the unfatigued group, no significant fatigue effects were found in behavioral response times and accuracies to specific auditory targets. In sharply contrast to the unfatigued group, the fatigued group showed significantly delayed response times and less response accuracies. However, no significant changes in accuracies for a working memory task were observed in both groups.

• Journal of IKEEE
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• v.12 no.1
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• pp.65-74
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• 2008

One of the popular methods used for pattern classification is the MBR (Memory-Based Reasoning) algorithm. Since it simply computes distances between a test pattern and training patterns or hyperplanes stored in memory, and then assigns the class of the nearest training pattern, it is notorious for memory usage and can't learn additional information from new data. In order to overcome this problem, we propose an incremental learning algorithm (iMPA). iMPA divides the entire pattern space into fixed number partitions, and generates representatives from each partition. Also, due to the fact that it can not learn additional information from new data, we present iMPA which can learn additional information from new data and not require access to the original data, used to train. Proposed methods have been successfully shown to exhibit comparable performance to k-NN with a lot less number of patterns and better result than EACH system which implements the NGE theory using benchmark data sets from UCI Machine Learning Repository.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.9 no.2
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• pp.15-21
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• 2014

The long memory properties of the hedge ratio for stock and futures have not been systematically investigated by the extant literature. To investigate hedge ratio' long memory, this paper employs a data set including KOSPI200 and S&P500. Coakley, Dollery, and Kellard(2008) employ a data set including a stock index and commodities foreign exchange, and suggested the S&P500 to be a fractionally integrated process. This paper firstly estimates hedge ratios with two dynamic models, BEKK(Bollerslev, Engle, Kroner, and Kraft) and diagonal-BEKK, and tests the long memory of hedge ratios with Geweke and Porter-Hudak(1983)(henceforth GPH) and Lo's modified rescaled adjusted range test by Lo(1991). In empirical results, two hedge ratios based on KOSPI200 and S&P500 show considerably significant long memory behaviours. Thus, such results show the hedge ratios to be stationary and strongly reject the random walk hypothesis on hedge ratios, which violates the efficient market hypothesis.

• The Journal of the Acoustical Society of Korea
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• v.11 no.3
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• pp.40-52
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• 1992

In this paper, we propose the speaker adaptive word recognition method using a mapped membership function, in order to absorb a fluctuation owing to personal difference which is a problem of speaker independent speech recognition. In the training procedure of this method, the mapped membership function is made with the fuzzy theory introducded into a mapped codebook, between an unknown speaker's spectrum pattern and a standard speaker's one. In the recognition procedure, an input pattern of an unknown speaker is reconstructed to the pattern which is adapted to that of a standard speaker by the mapped membership function. To show the validity of this method, word recognition experiments are carried out using 28 DDD area names. The recognition rate of the conventional speaker-adaptive method using a mapped codebook by VQ is 64.9[%], and that made by a fuzzy VQ is 76.2[%]. Throughout the experiment using a mapped membership function, we can achieve 95.4[%] recognition rate. This shows that our proposed method is more excellent in recognition performance. Moreover, this method doesn't need an iterative training procedure to make the mapped membership function, and memory capacity and computation requirements for this method are reduced to 1/30 and 1/500 time of those for the conventional method using a mapped codebook, respectively.