• The Journal of Korean Medicine
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• 제33권4호
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• pp.50-59
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• 2012

Objectives: This study aimed to compare the effects of high frequency electroacupuncture, low frequency electroacupuncture and manual acupuncture on the autonomic nervous system in stroke patients by using a heart rate variability measuring device. Methods: Thirty-nine participants were recruited and each participated in the high frequency electroacupuncture group, low frequency electroacupuncture group, manual acupuncture group and non-acupuncture group. Some participants received needle insertion with 100 Hz stimulation, with 2Hz stimulation and manual stimulation under mental arithmetic stress during 2 sections. Other participants maintained in the supine position without acupuncture under mental arithmetic stress during the 2 sections. Acupuncture needles were directly inserted perpendicularly to the right Liv 3 acupoint followed by delivery of electric pulses to these points for 8 minutes. Heart rate variability was measured 8 minutes before and 16 minutes after acupuncture stimulation by a heart rate variability measuring system. Results: We found a significant elevated HF total power between 1 section and 2 section and between 1 section and 4 section in the non-acupuncture group, between 3 section and 4 section in the 100Hz electroacupuncture group, and between 1 section and 2 section in the manual acupuncture group and with no change in the 2Hz electroacupuncture group. We also found a significant VLF total power between 2 section and 3 section in the 2Hz electroacupuncture group and between 1 section and 4 section and between 2 section and 4 section in the 100Hz electroacupuncture group. All four groups showed no significant differences in other parameters including heart rate mean, low-frequency power, and the ratio of low-frequency power to high-frequency power. Conclusions: This study may be a basis for research about effects of acupuncture and electroacupuncture because the parameters measured, heart rate variability, showed differences according to acupuncture.

• Journal of the Society of Naval Architects of Korea
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• 제42권6호
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• pp.644-653
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• 2005

In general the loads due to ocean wave are considered as main design parameters governing the global structural safety of VLFS (Very Large Floating Structure). In order to predict design wave loads accurately, hydro-elastic analysis must be conducted considering the initial global flexural rigidity of VLFS. However, in order to determine the structural scantling of major members (deck, bottom, side panels and longitudinal / transverse BHD etc.), static load and design wave loads must be given as explicit form generally. Therefore in order to determine a proper structural arrangement and scantlings of VLFS at initial design stage, both calculations of structural scantling and hydro-elastic analysis for wave conditions must be conducted iteratively and the convergence of their results must be checked. On this paper, based on the case design of a 500×300 m size's floating marina resort, the details of structural design technique using hydro-elastic analysis are explained and discussed. At first, the environmental conditions and the system requirements of the design of marina resort are described. The scantling formulas for the major members of pontoon type VLFS are proposed from the local and global design points of view. Considering the design wave loads as well as static design loads, the structural safety is checked iteratively.

• Korean Journal of Biological Psychiatry
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• 제16권2호
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• pp.69-75
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• 2009

Objectives : The detrended fluctuation analysis is one of the nonlinear methods for the investigation of biological time series. It quantifies the fractal scaling properties and is known to be useful in the evaluation of long-range correlations in time series. The heart rate variability(HRV) of obstructive sleep apnea syndrome (OSAS) patients during nighttime was analyzed by detrended fluctuation analysis to assess its relationship with the severity of the symptoms. Methods : Fifty nine untreated male OSAS patients with moderate to severe symptoms(mean age=45.4${\pm}$11.7 years, apnea-hypopnea index, AHI${\geq}$15) underwent nocturnal polysomnography. Moderate(AHI=15-30, N=22) and severe(AHI>30, N=37) OSAS patients were compared for the indices derived from detrended fluctuation analysis and frequency domain analysis of HRV. Results : In the detrended fluctuation analysis, the alpha values were 0.75${\pm}$0.11 and 0.82${\pm}$0.07 for the severe and the moderate OSAS groups respectively. The difference was significant(p<.01). The alpha value had negative correlation with AHI(r=-.425, p=.001). Negative correlation coefficients were also found in the relationships between the alpha values and very low frequency(VLF)(r=-.425, p=.001), low frequency(LF)(r=-.633, p= <.001) and the LF/HF ratio(r=-.305, p=.019) respectively. LF/HF ratio(p=.005) was higher in the severe OSAS group compared to that of the moderate OSAS group. Conclusion : In this study, the detrended fluctuation analysis showed the significant difference between the two OSAS groups classified according to their severity of symptoms. The scaling exponent showed the negative correlation with AHI and indicies of frequency domain analysis. This result suggests that detrended fluctuation analysis can be helpful to estimate the severity of OSAS.

• Journal of Acupuncture Research
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• 제25권4호
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• pp.71-80
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• 2008

Objectives : The 7-zonediagnostic system is a diagnostic device to predetermine bodily locations by measuring the energy of body. This study was to investigate the relation between the different patterns of Zone 4 of Factor AA in VEGA DFM 722 (VEGA, Germany), 7-zone-diagnositic system and heart rate variability. Methods : We made three groups according to the Factor AA patterns of VEGA DFM 722. The Factor AA pattern of Group A is that the red bar graph of zone 4 was higher than the normal range. The Factor AA patterns of Group B was that the red bar graph of zone 4 was located at the normal range. The Factor AA patterns of Group C was that the red bar graph of zone 4 was lower than the normal range. We investigated how to difference of the index of heart rate variability(HRV, LX-3202, LAXTHA, Korea) according to each groups. Results : Complexity, HRV-index, RMSSD, SDSD values of Group B were higher than other Groups. pNN50 values of Group B were lower than other groups. And Ln(TP), Ln(VLF), Ln(LF), Ln(HF) values of Group B were higher than other groups. Conclusions : We presumed that Group B was healthier than other groups for the stress.

• The Journal of Korean Obstetrics and Gynecology
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• 제28권3호
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• pp.11-20
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• 2015

Objectives This study is performed to recognize the relationship between atrophic vaginitis and stress that have an affect on autonomic nervous system. Methods We studied 47 patients who visited Kangnam Kyunghee Korean Hospital Medical Examination Center from November, 2013 to June, 2014. They were devided into two groups, atrophic vaginitis group (AV, n=18) and non-atrophic vaginitis group (NAV, n=29). We compared the result of HRV between the two groups. Results The mean of The standard deviation of NN intervals (SDNN), the square root of the mean squared difference of successive NNs (RMSSD) in AV group was lower than NAV group, but there was no significant difference between the two groups. Total power (TP), low frequency (LF) and very low frequency (VLF) of AV group was significantly lower than NAV group. There was no significant difference in high frequency (HF). Conclusions Women with atrophic vaginitis is expected to have low adaptive capacity against stress.

• The Journal of Korean Obstetrics and Gynecology
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• 제28권3호
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• pp.30-39
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• 2015

Objectives This study aims to analyze Heart Rate Variability (HRV) in women after missed abortion compared with healthy women Methods We studied 35 women who visited Kang-Nam Kyung-Hee Korean Hospital after missed abortion from 01 January 2012 to 28 February 2015 (missed abortion group) and 35 normal women visiting medical examination center from 1 January 2014 to 31 December 2014 (Normal Group). We measured HRV of each women and investigated the difference of HRV between two groups. Results The standard deviation of NN intervals (SDNN) in Missed abortion group is lower than normal group. The square root of the mean square difference of successive NNs (RMSSD) in Missed abortion group is lower than normal group. However there was no significant difference. Total Power (TP) and Low frequency power (LF) is significantly lower in Missed abortion group compared with normal group. High frequency power (HF), Very low frequency power (VLF) and LF/HF ratio in missed abortion group is lower than normal group. but There was no significant difference. Conclusions Missed abortion group is lower in function of overall autonomic nervous system, especially sympathetic nerve.

• The Journal of Korean Obstetrics and Gynecology
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• 제20권3호
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• pp.164-177
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• 2007

Purpose: The purpose of this study is to analysis on the Heart Rate Variability(HRV) of some dysmenorrhoea patients. Methods : We studied 30 patients visiting Kyung Hee University East-West Neo Medical Center from 7th Febrary 2007 to 22th Febrary 2007. Women with organic disease were excluded from this study. The severity of dysmenorrhoea were measured by Multidimensional Verbal Rating scale(MVRS), Verbal Rating scale (VRS) and Visual Analog Scale(VAS). And HRV was recorded. Results : According to comparison of Means of HRV values among the groups of None, Mild and Moderate, the points of almost all values were kept by order of Moderate group-Mild group-None group. Among these, the statistically significant things are PR, SDNN, Ln (TP), Ln (VLF), Ln (LF). According to correlation analysis between dysmenorrhoea and HRV, specially, there were many correlations in VRS2. Among these, the statistically significant things are LF norm, HF norm, LF/HF ratio(p<0.05L). Conclusion : The results suggest that HRV is related to dysmenorrhoea. We may analyze that dysmenorrhoea is related to, specially, increased activities of sympathetic nerve. We need more study for settling this.

• The Journal of Korean Obstetrics and Gynecology
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• 제21권3호
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• pp.99-110
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• 2008

Purpose: Premenstrual syndrome(PMS) is a collection of physical, psychological and emotional symptoms related to a women's menstrual cycle. The symptoms are related with Autonomic Nervous system. The purpose of this study is to investigate the activity of Autonomic Nervous system in women with premenstrual syndrome(PMS) by using Heart Rate Variability(HRV). Methods: We studied 26 patients visiting ㅇㅇ hospital from 26th December 2005 to 26th April 2006. Activity of Autonomic Nervous system was assesed by means of Heart Rate Variability(HRV). The subjects were categorized in two groups, PMS group(10) and non-PMS group(16). We studied the difference of HRV between two groups by Mann-Whitney U-test using SPSS for windows (version 12.0). Results: SDNN of PMS group was non-significantly lower than non-PMS group. RMS-SD of PMS group was significantly lower than non-PMS group. Mean PR of PMS group was non-significantly higher than non-PMS group. TP, VLF, LF, HF norm of PMS group was non-significantly lower than non-PMS group. HF of PMS group was significantly lower than non-PMS group. LF norm, LF/HF ratio of PMS group was non-significantly higher than non-PMS group. Conclusion: The results suggest that PMS can be related to decreased activity of parasympathetic nervous system. HRV can be useful to diagnose PMS. The more studies to diagnose PMS would be needed.

• Journal of Biomedical Engineering Research
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• 제40권2호
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• pp.62-67
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• 2019

The purpose of this study was to evaluate the performance of deep neural network model in order to determine whether there is a risk factor for coronary artery disease based on the cardiac variation parameter. The study used unidentifiable 297 data to evaluate the performance of the model. Input data consists of heart rate parameters, which are SDNN (standard deviation of the N-N intervals), PSI (physical stress index), TP (total power), VLF (very low frequency), LF (low frequency), HF (high frequency), RMSSD (root mean square of successive difference) APEN (approximate entropy) and SRD (successive R-R interval difference), the age group and sex. Output data are divided into normal and patient groups, and the patient group consists of those diagnosed with diabetes, high blood pressure, and hyperlipidemia among the various risk factors that can cause coronary artery disease. Based on this, a binary classification model was applied using Deep Neural Network of deep learning techniques to classify normal and patient groups efficiently. To evaluate the effectiveness of the model used in this study, Kernel SVM (support vector machine), one of the classification models in machine learning, was compared and evaluated using same data. The results showed that the accuracy of the proposed deep neural network was train set 91.79% and test set 85.56% and the specificity was 87.04% and the sensitivity was 83.33% from the point of diagnosis. These results suggest that deep learning is more efficient when classifying these medical data because the train set accuracy in the deep neural network was 7.73% higher than the comparative model Kernel SVM.

• The Journal of the Society of Stroke on Korean Medicine
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• 제6권1호
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• pp.9-16
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• 2005

Objective : The heart rate variability is very useful indicator to study the function of the autonomic nervous system(ANS), and the physiologic signals can be observed based on the changes of the ANS of the heart. In order to assay the effects of the laser exposing to healthy subjects, the double blind test has been performed. Methods : This study included 62 healthy adults who have not any ANS disease and had normal sinus rhythm in electrocardiogram. The control group consisted of 31 subjects, laser group consisted of 31 subject. HRV was measured for 5 minutes before laser irradiation, sham and real laser irradiated for 30 minutes and than HRV remeasured for 5 minutes. Statistical significance was evaluated by independent T-test. Results : Mean HRV, Ln(VLF), Ln(HF), Ln(TP) of both groups at post-laser period decreased compared with that of the pre-laser period. Ln(LF) of both groups at post-laser period increased compared with that of the pre-laser period. LF/HF, SDNN of real laser group decreased and sham group decreased. Conclusions : There is no difference between two groups. The reason is presumed that all the studied subjects are healthy adults, and also the short and single transcutaneous laser irradiation would not influence upon changes of the ANS. The further study must be followed.