• Psychiatry investigation
• /
• v.15 no.11
• /
• pp.1087-1093
• /
• 2018

Objective Posttraumatic stress disorder (PTSD) is distinct from anxiety disorders in its etiology and clinical symptomatology, and was reclassified into trauma- and stressor-related disorders in DSM-5. This study aimed to find neurophysiological correlates differentiating PTSD from anxiety disorders using resting-state quantitative electroencephalography (qEEG). Methods Thirty-six patients with either PTSD or acute stress disorder and 79 patients with anxiety disorder were included in the analysis. qEEG data of absolute and relative powers and patients' medication status on the day of qEEG examination were obtained. Electrodes were grouped into frontal, central, and posterior regions to analyze for regional differences. General linear models were utilized to test for group differences in absolute and relative powers while controlling for medications. Results PTSD patients differed from those with anxiety disorders in overall absolute powers [F(5,327)=2.601, p=0.025]. Specifically, overall absolute delta powers [F(1,331)=4.363, p=0.037], and overall relative gamma powers [F(1,331)=3.965, p=0.047] were increased in PTSD group compared to anxiety disorder group. Post hoc analysis regarding brain regions showed that the increase in absolute delta powers were localized to the posterior region [F(1,107)=4.001, p=0.048]. Additionally, frontal absolute gamma powers [F(1,107)=4.138, p=0.044] were increased in PTSD group compared to anxiety disorder group. Conclusion Our study suggests increased overall absolute delta powers and relative gamma powers as potential markers that could differentiate PTSD from anxiety disorders. Moreover, increased frontal absolute gamma and posterior delta powers might pose as novel markers of PTSD, which may reflect its distinct symptomatology.

• Honam Mathematical Journal
• /
• v.37 no.2
• /
• pp.265-267
• /
• 2015

Let G be a cyclic group of prime power order. There is a natural embedding of $\mathbb{Z}$[G] into a product of rings of integers of cyclotomic fields. In this paper we determine the image of powers of the augmentation ideal.

• Journal of The Korean Association For Science Education
• /
• v.32 no.1
• /
• pp.46-63
• /
• 2012

The purpose of this research is to explore factors which influence visitors' attention on exhibition panels by analyzing visitors' attention according to topic types and visitor group types. The subjects of this research are exhibition panels of a Tesla Coil exhibition in the Gwacheon National Science Museum. The exhibition panels' topic are basic concepts, explanations of phenomena, operating principles, applications and historical background. These topics are selected through a survey of visitors' intellectual needs for a Tesla Coil. Five new exhibition panels according to the topics are developed and visitor groups' behaviors in front of the panels are recoded in natural situations. The total participant groups are 586 groups, which includes individual student (30.0%), individual adult (20.6%), student group (28.2%), adult group(2.4%), and family group (18.8%). Visitors' attention to exhibition panels is sub-categorized into attracting power and holding power. Attracting power is defined by the percentile of group numbers who attend to an exhibition panel more than 3 seconds to the total group numbers who attend to an exhibition panel for more than a glance. Holding power is defined by average attention time and decay time. The attracting powers of historical background and application panels are 72.3% and 68.8% respectively, while that of the basic concept panel is 47%. Average attention times of explanation of phenomena and operating principle are 37.0 and 34.2 seconds, while those of historical background and application panels are 25.4 seconds. The decay times of each panel shows the same patterns of average attention times. Attracting powers of panels easy to approach and holding powers of panels with in-depth scientific concepts seems to be high. Attracting powers of the individual adult, family, and student group are 66.9%, 66.4% and 62.4% respectively, while the attracting power of the adult group and individual student are 57.1%, and 55.7%. Average attention times of the student group, family, adult groups are 34.0, 33.0, 31.6 seconds respectively, while that of individual student is 19.5 seconds. The decay times of each group shows the same patterns of average attention times. Both of attracting powers and average attention times of the student group and family group are high, while both of individual student are low. Tentatively, attracting powers of exhibition panels seems to be influenced more by topic types of panels, and holding power seems to be influenced more by group type. But these results are very limited and further studies are needed.

• Journal of Life Science
• /
• v.22 no.5
• /
• pp.613-620
• /
• 2012

To evaluate the effects of sleep habits on the powers of beta waves and the sensory motor rhythm of the electroencephalogram (EEG), female college student subjects were divided into four groups, according to their sleep habits, as follows: GSHG (Good Sleep Habit Group), CSHG (Common Sleep Habit Group: late bedtime), CSDG (Cognitive Sleep Disorder-Delayed Sleep Phase Syndrome Group), and NSDG (Non-cognitive Sleep Disorder-Delayed Sleep Phase Syndrome Group). Brain function was stimulated by reading a book for 3 min in the morning (9~12 am) and the EEG was measured. According to the results, the powers of the beta waves and sensory motor rhythm were not different during the resting period among the four groups. However, during the reading stimulation period, the powers of beta waves and the sensory motor rhythm in the GSHG were significantly greater than in the other groups ($p$ <0.05). Beta powers during stimulation also increased in all brain areas in the GSHG ($p$ <0.05). Interestingly, these were decreased in the frontal and temporal lobes in the CSHG by the reading stimulation ($p$ <0.05). On the other hand, sensory motor rhythm, which represents focusing efficacy, only improved in the GSHG. These results indicate that the brain's focusing function during the reading stimulation was not properly operating in the morning in the female college students who had a delayed bedtime and bad sleep habits.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.21 no.5
• /
• pp.1240-1255
• /
• 1996

This paper suggests power optimization technique in multi-level SCPC system as a method for efficient utilization of limited satellite power. The power optimization is realized by optimal assignment of satellite input carrier powers considering interference and noise generated in up-link and down-link. The Fletcher-Powell algorithm searching minimum(or maximum) point using gradient information is used to detemine the optimal input carrier powers. To apply Flectcher-Powell algorithm mathematical descriptions and their partial derivatives to interference and nose are presented. Because a target, which should be optimized, is satellite input carrier power, amplitude of each carrier group will be assumed to be an independent variable. The performance criterion for optimal power assignmentis classified into 4 categories with respect to CNR of destination receiver earth station to meet the requirement for various satellite link environment. Simulation results for two-level, four-level and six-level SCPC system are presented.

• The Journal of Korean Medicine
• /
• v.38 no.3
• /
• pp.185-196
• /
• 2017

Backgrounds: Inpatient Classification System for Korean Medicine (KDRG-KM) was developed and has been applied for monitoring the costs of KM hospitals. Yet severity of patients' condition is not applied in the KDRG-KM. Objectives: This study aimed to develop the severity classification methods for KDRG-KM and assessed the explanation powers of severity adjusted KDRG-KM. Methods: Clinical experts panel was organized based on the recommendations from 12 clinical societies of Korean Medicine. Two expert panel workshops were held to develop the severity classification options, and the Delphi survey was performed to measure CCL(Complexity and Comorbidity Level) scores. Explanation powers were calculated using the inpatient EDI claim data issued by hospitals and clinics in 2012. Results: Two options for severity classification were deduced based on the severity classification principle in the domestic and foreign DRG systems. The option one is to classify severity groups using CCL and PCCL(Patient Clinical Complexity Level) scores, and the option two is to form a severity group with patients who belonged principal diagnosis-secondary diagnosis combinations which prolonged length of stay. All two options enhanced explanation powers less than 1%. For third option, patients who received certain treatments for severe conditions were grouped into severity group. The treatment expense of the severity group was significantly higher than that of other patients groups. Conclusions: Applying the severity classifications using principal diagnosis and secondary diagnoses can advance the KDRG-KM for genuine KM hospitalization. More practically, including patients with procedures for severe conditions in a severity group needs to be considered.

• Journal of Korean Home Economics Education Association
• /
• v.10 no.2
• /
• pp.13-28
• /
• 1998

The purpose of this study is to compare of learning effects between the inquiry training model and traditional lecture method in the unit of food and nutrition of home economics in the middle school and propose a teaching-learning method of home economics in the middle school.For this study I sampled one hundred students both male and female who were in the first grade students of middle school in Ansan city.The students were divided into two groups each of which was composed of one male class and one female class. One was called the inquiry training model group, which was taught by the inquiry training model, the other the traditional lecture method group, which was taught by traditional lecture method .They learned about food and nutrition unit during the same time. To evaluate the effectiveness of learning, learning achievement degree, instruction interest degree, and the powers of exploration process, a creativity lest by using a Questionnaire was gIven.The resuits of this study are as follows: 1. In the traditional lecture method group between the inquiry training model one, the difference of learning achievement degree was not significant. The score of learning achieve ment degree in the inquiry training group, the female class got higher scores than .the maleone, but the difference was not significant. 2. In the test of instruction interest degree, the traditional lecture method group got higher scores than the inquiry training model one. (p<.001.). In the inquiry training group the male class got higher scores than the f ema Ie one. (p < .001 ) 3. In the test of powers of exploration process, the traditional lecture method group got higher scores than the inquiry training model one.( p< .00 1). In the inquiry training group, the male class got higher scores than the female one, but the difference was not significant. 4. In the test of creativity, the traditional lecture method group got higher scores than the inquiry training one. (p < .00 1). In the inquiry training group, the female class got higher scores than the male one, but the difference was not significant Therefore, the inquiry training model is the more effective instruction model for both male and female students, rather than the traditional lecture method for instruction interest de¬gree, powers of exploration process, creativity and extends instruction interest degree for the male studentsale students.

• Journal of the Korean Mathematical Society
• /
• v.54 no.1
• /
• pp.177-191
• /
• 2017

In this note we consider the right unit-duo ring property on the powers of elements, and introduce the concept of weakly right unit-duo ring. We investigate first the properties of weakly right unit-duo rings which are useful to the study of related studies. We observe next various kinds of relations and examples of weakly right unit-duo rings which do roles in ring theory.

• The Korean Journal of Physiology and Pharmacology
• /
• v.3 no.6
• /
• pp.605-613
• /
• 1999

The purpose of the present study was to evaluate cardiovascular regulation during passive standing (PS) after ethanol ingestion by spectral analysis of heart rate variability (HRV) in flushed and nonflushed subjects. Of 24 young male subjects, 8 belonged to flushed group (F) and 16 to nonflushed group (NF). Two sessions of 10-min PS were performed before and after ethanol (0.5 g/kg) ingestion. Powers of R-R interval variability in very low frequency $(VLF,\;0{\sim}0.05\;Hz),$ low frequency $(LF,\;0.05{\sim}0.15\;Hz)$ and high frequency $(HF,\;0.15{\sim}0.50\;Hz)$ bands, normalized powers (LFn and HFn) and LF/HF ratio were obtained. After ethanol ingestion, F showed higher heart rate than NF. PS increased LFn $(+22.9{\pm}3.6\;in\;NF,\;+12.8{\pm}4.7$ in F, in normalized units) and LF/HF $(+3.10{\pm}0.57\;in\;NF,\;+3.00{\pm}1.08\;in\;F)$ and decreased HFn powers. Ethanol ingestion increased LFn and LF/HF and decreased HFn. PS after ethanol resulted in higher LFn and LF/HF and lower HFn than the prior PS. F showed a greater and more sustained HRV change than NF after ethanol. In conclusion, PS or ethanol ingestion increased LFn and LF/HF and decreased HFn. Flushed subjects showed an accentuated HRV response to ethanol.

• Journal of the Ergonomics Society of Korea
• /
• v.29 no.2
• /
• pp.189-196
• /
• 2010

The study is to find relative EEG power spectrum and pattern of coherence discriminating attentive and inattentive hand movements. Eight undergraduate students aged from 20 to 27 who had not hand disability participated in this study. Participants were asked to perform visuo-motor task. EEG was measured at C3 in 10~20 international system and four areas orthogonally directed 2.5cm away from C3. Significant result discriminating movement and rest was found through coherence analysis between movement areas or movement area and non-movement area, but was individually different. Because it was anticipated that major factors caused by the differences among individuals were attributed to the attention of the subjects, relative power of alpha and beta bands was identified. As a result, significant relative powers of alpha and beta bands were found in a group of high coherence level, but were not found in a group of low level. Next, participants were divided into two groups according to relative powers of alpha and beta bands. The comparison between two groups was performed. As a result, the coherence of the alpha band in the attentive group was greater than that of the inattentive group. It was found that the coherence of the beta band in the inattentive group was happening. Therefore, individual differences of coherence were influenced by attention. The significant coherence patterns that could discriminate attentive movement and inattentive movement were found.