• 제목/요약/키워드: $\alpha$ wave

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Comparison of EEG Characteristics between Dementia Patient and Normal Person Using Frequency Analysis Method (주파수분석법에 의한 치매환자와 정상인의 뇌파특성 비교)

  • Jang, Yun-Seok;Park, Kyu-Chil;Han, Dong-Wook
    • The Journal of the Korea institute of electronic communication sciences
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    • v.9 no.5
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    • pp.595-600
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    • 2014
  • Nowadays our society is rapidly transforming into an aging society. A better understanding of dementia is a high priority in the aging society. Therefore our study is basically aimed at understanding characteristics of EEG signals from dementia patients. Firstly, we analyzed spontaneous EEG signals from normal persons and dementia patients to distinguish their characteristics. The EEG signals are recorded with 16 electrodes and we classified the EEG signals form the signals according to frequency band. To obtain the clean EEG signals, we used cross correlation function between two channels. From the analysis results, we can observe that the EEG characteristics from dementia patients are distinctly different from that from normal persons.

A Study on the Characteristics of Electroencephalogram for the Evaluating Words of Soundscape Sound Source When Visual Information is Suggested (시각정보 제공에 따른 사운드스케이프 음원평가어휘별 뇌파변화에 관한 연구)

  • Song, Min-Jeong;Shin, Hoon
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.21 no.7
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    • pp.629-636
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    • 2011
  • In this study, survey experiment and EEG test was carried out to know the effect of visual images on EEG for evaluating words of soundscape sound source with 18 subjects. Analysis on the EEG were executed to know the difference according to with and without visual images. Followings are results of this study. 1) There is no big difference with visual images in soundscape sound evaluating adjectives such as "Full", "Clear", "Enjoyable" whereas there is a big difference in soundscape sound evaluating adjectives such as "Pleasant", "Comfortable", "Gentle", "Sonorous". 2) There is a tendency that soundscape sound source which is consist of single sound source shows + 1 above increase in survey test when visual image is suggested whereas soundscape sound source which is consist of one more sound source shows - 1 below decrease in survey test. 3) Statistical analysis was used to know considerable probability. ${\alpha}$-wave has a considerable probability and Maximum level difference occurring brain spots were number 1 and 2.

Estimation of Site Response Characteristics at Town Fortress Areas Damaged by Historical Earthquakes (역사 지진 피해 발생 읍성 지역의 부지 응답 특성 평가)

  • Sun, Chang-Guk;Bang, Eun-Seok;Chung, Choong-Ki;Kim, Dong-Soo
    • Proceedings of the Earthquake Engineering Society of Korea Conference
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    • 2006.03a
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    • pp.125-132
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    • 2006
  • To estimate the local site effects at two town fortress areas where stone parapets were collapsed during historical earthquakes, site characteristics were evaluated using borehole drillings and seismic tests and equivalent-linear site response analyses were conducted based on the shear wave velocity (Vs) profiles determined from site investigations. The study sites are categorized as site classes C and B according to the mean Vs to 30 m ranging from 500 to 850 m/s, and their site periods are distributed in short period range of 0.06 to 0.16 sec. For site class C in the study areas, the short-period (0.1-0.5 sec) and mid-period (0.4-2.0 sec) site coefficients, $F_{\alpha}$ and $F_\nu$ specified in the Korean seismic design guide, underestimate the ground motion in short-period band and overestimate the ground motion in mid-period band, respectively, due to the characteristics showing high amplification in short period range, which can result in the collapse of stone parapets having the short natural period.

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THE EFFECT OF NITROGEN ON THE MICROSTRUCTURE AND THE CORROSION RESISTANCE OF Fe-Hf-C-N THIN FILMS

  • Choi, J.O.;Han, S.H.;Kim, H.J.;Kang, I.K.
    • Journal of the Korean Magnetics Society
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    • v.5 no.5
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    • pp.641-644
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    • 1995
  • We have studied the effect of the nitrogen on the microstructure, thermomagnetic properties and corrosion resistance of Fe-Hf-C-N nanocrystalline thin films with high permeability and high saturation magnetization. These films were fabricated by reactive sputtering in $Ar+N_{2}$ plasma using an rf magnetron sputtering apparatus. As $P_{N2}$ increases, the microstructure changes from amorphous to crystalline $\alpha$-Fe phase and again returns to amorphous one. Spin wave stiffness constant increases with $P_{N2}$ until 5% $P_{N2}$, and then decreases with the further increase. This trend corresponds well with that of the microstructure with increasing $P_{N2}$. The Fe-Hf-C-N films with over 3% $P_{N2}$ show higher corrosion resistance than the N-free Fe-Hf-C films. The Fe-Hf-C-N films are considered to have high potentials for the head core materials suitable for high density recording systems, owing to their excellent soft magnetic properties and corrosion resistance.

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Sex differences in QEEG in adolescents with conduct disorder and psychopathic traits

  • Calzada-Reyes, Ana;Alvarez-Amador, Alfredo;Galan-Garcia, Lidice;Valdes-Sosa, Mitchell
    • Annals of Clinical Neurophysiology
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    • v.21 no.1
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    • pp.16-29
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    • 2019
  • Background: Sex influences is important to understand behavioral manifestations in a large number of neuropsychiatric disorders. We found electrophysiological differences specifically related to the influence of sex on psychopathic traits. Methods: The resting electroencephalography (EEG) activity and low-resolution brain electromagnetic tomography (LORETA) for the EEG spectral bands were evaluated in 38 teenagers with conduct disorder (CD). The 25 male and 13 female subjects had psychopathic traits as diagnosed using the Antisocial Process Screening Device. All of the included adolescents were assessed using the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision (DSM-IV-TR) criteria. The visually inspected EEG characteristics and the use of frequency-domain quantitative analysis techniques are described. Results: Quantitative EEG (QEEG) analysis showed that the slow-wave activities in the right frontal and left central regions were higher and the alpha-band powers in the left central and bitemporal regions were lower in the male than the female psychopathic traits group. The current source density showed increases in paralimbic areas at 2.73 Hz and decreases in the frontoparietal area at 9.37 Hz in male psychopathics relative to female psychopathics. Conclusions: These findings indicate that QEEG analysis and techniques of source localization can reveal sex differences in brain electrical activity between teenagers with CD and psychopathic traits that are not obvious in visual inspections.

Verification of Effectiveness of Wearing Compression Pants in Wearable Robot Based on Bio-signals (생체신호에 기반한 웨어러블 로봇 내 부분 압박 바지 착용 시 효과 검증)

  • Park, Soyoung;Lee, Yejin
    • Journal of the Korean Society of Clothing and Textiles
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    • v.45 no.2
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    • pp.305-316
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    • 2021
  • In this study, the effect of wearing functional compression pants is verified using a lower-limb wearable robot through a bio-signal analysis and subjective fit evaluation. First, the compression area to be applied to the functional compression pants is derived using the quad method for nine men in their 20s. Subsequently, functional compression pants are prepared, and changes in Electroencephalogram (EEG) and Electrocardiogram (ECG) signals when wearing the functional compression and normal regular pants inside a wearable robot are measured. The EEG and ECG signals are measured with eyes closed and open. Results indicate that the Relative alpha (RA) and Relative gamma wave (RG) of the EEG signal differ significantly, resulting in increased stability and reduced anxiety and stress when wearing the functional compression pants. Furthermore, the ECG analysis results indicate statistically significant differences in the Low frequency (LF)/High frequency (HF) index, which reflect the overall balance of the autonomic nervous system and can be interpreted as feeling comfortable and balanced when wearing the functional compression pants. Moreover, subjective sense is discovered to be effective in assessing wear fit, ease of movement, skin friction, and wear comfort when wearing the functional compression pants.

Identifying the scientifically giftedness through brain's cognitive function characteristics (뇌의 인지기능 특성을 통한 과학 영재성 판별)

  • Ha, Jong-Duck;Song, Kyong-Ae
    • Journal of Gifted/Talented Education
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    • v.15 no.2
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    • pp.77-100
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    • 2005
  • This study attempted a new approach to the methods of identifying the scientifically giftedness in relation to the recent emphasis on the education for the scientifically gifted. This study focused on the processes of the cognition achievements, while only the results have been studied until now. Theoretical backgrounds about the ways of identifying the gifted, the research procedures about brain functions, and the information procedures about brain data were reviewed. Eleven scientifically gifted and 10 normal children from the 4th to the 6th grades were selected to analyze the characteristics of their brain waves with brain wave measuring instrument for PCs. The results showed that the scientifically gifted, while studying scientific and creative problems, used their right brain more than their left. When solving these problems, they utilized more of their theta and alpha brain waves than those normal children. In addition, theta brain waves of the scientifically gifted were rather active during these activities and this phenomenon was more distinctive in their right brain rather than their left. Thereby, this study implies that the characteristics of brain waves during the moments of solving certain problems can be used as a method to identify the scientifically gifted.

Evaluation of convergence Elasticity of Liver Fibroscan used measurement with Ultrasonography (초음파를 이용한 간 섬유화 스캔 검사의 융합 탄성도 측정 평가)

  • Kim, Min-Jeong;Han, Man-Seok;Jang, Jae-Uk
    • Journal of the Korea Convergence Society
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    • v.8 no.5
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    • pp.79-85
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    • 2017
  • The purpose of this research was to evaluate the clinical and the instrument of convergence utility of transient elastography (FibroScan(R):electromagnetic wave) in diagnosing and treating liver ailments through a comparison and an analysis between liver function blood test and transient elastography (FibroScan(R)) in patients with chronic hepatitis B virus infection. Of all the patients with chronic hepatitis B virus infection who visited clinic B in Daejeon City between July 1, 2015, and February 28, 2016, 75 who underwent a FibroScan(R) test were selected for this study. Their laboratory and liver function test results were compared for a correlation analysis before constructing an ROC (Receiver Operation Characteristic) curve. Aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels were 0.572 and 0.502, respectively, and showed highest correlation with fibrosis score, with statistical significance (p<0.000). Gamma glutamyltranspeptidase, total bilirubin, and alkaline phosphatase levels also showed relatively significant correlations in this order of sequence, while -fetoprotein and total protein levels did not show any statistically significant values. Albumin (-0.449) and platelet levels (-0.373) showed negative correlations with each other and no correlation with fibrosis score (p < 0.000). As liver fibrosis worsened, the accuracy of the ROC curve increased. At the F4 stage, which is the cirrhotic stage, the largest area under the curve was observed. FibroScan(R) showed significant correlation with the ALT (serum glutamic pyruvic transaminase) and AST (serum glutamic oxaloacetic transaminase) levels in the liver function test, which is a routine test for patients with chronic liver ailments. This implies that fibrosis correlates with liver inflammation severity.

Evaluations on Driver's Sensibility Changes by Sudden Start and Sudden Stop Conditions in Driving Simulator (자동차 시뮬레이터에서의 급출발 및 급제동에 따른 운전자 감성 평가)

  • 전효정;민병찬;성은정;김철중
    • Science of Emotion and Sensibility
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    • v.5 no.4
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    • pp.51-57
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    • 2002
  • The purpose of the study was to measure and compare driver's psychophysiological responses in different driving conditions through driving simulator. Twelve male adults(more than 1 year of driving experience) were assigned to four different driving conditions, such as normal speed(70㎞/h), sudden start(0㎞/h→70㎞/h), and sudden stop(70㎞/h→0㎞/h), and their simulator sickness, subjective pleasantness and arousal, EEG, ECG, skin temperature, and GSR were measured. Subjective and physiological evaluations were executed before and after driving in each condition. The results showed that subjective pleasantness and arousal increased in sudden stop and sudden start conditions, relative to stop and normal speed conditions. As the central nervous responses, beta wave increased and alpha wave decreased in sudden stop and sudden start conditions, relative to stop and normal speed conditions. With regard to the autonomic responses, heart rate and GSR increased, while skin temperature decreased in sudden stop and sudden start conditions, which means an activation of sympathetic nervous system. The results suggested that based upon observation of the distinctive psychophysiological changes by driving conditions, it is possible to evaluate the human sensibility in dynamic environment.

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Effects of Yanghyuljanggeungunbo-tang(Yangxuezhuangjinjianbu-tang) and Cervi Cornu Parvum Pharmaco-Acupuncture on the Motor Function Recovery and Nerve Regeneration in Rats Induced Spinal Cord Injury (양혈장근건보탕(養血壯筋健步湯)과 녹용약침(鹿茸藥鍼)이 척수손상 유발 흰쥐의 운동기능 회복 및 신경재생에 미치는 영향)

  • Park, Ji-Yong;Sul, Jae-Uk;Kim, Sun-Jong;Choi, Jin-Bong;Shin, Mi-Suk
    • Journal of Korean Medicine Rehabilitation
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    • v.19 no.2
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    • pp.27-49
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    • 2009
  • Objectives : The purpose of this study was to investigate the effects of Yanghyuljanggeungunbo-tang(Yangxuezhuangjinjianbu-tang) and Cervi Cornu Parvum pharmaco-acupuncture in Spinal Cord Injury(SCI)-induced rats. Methods : The subjects were divided into 5 groups ; Normal, Control no treatment after SCI, Experimental I taken with Yanghyuljanggeungunbo-tang (Yangxuezhuangjinjianbu-tang) 500 mg/kg $0.5m{\ell}$ daily after inducing SCI. Experimental II taken with Cervi Cornu Parvum pharmaco-acupuncture at Taegye(KI3) and $Yangnungch{\acute{o}}n$(GB34) after inducing SCI and Experimental III taken with Yanghyuljanggeungunbo-tang(Yangxuezhuangjinjianbu-tang) 500 mg/kg $0.5m{\ell}$ and Cervi Cornu Parvum pharmaco-acupuncture at KI3 and GB34 to SCI-induced rats. After each operation, the present author observed the motor behavior recovery and nerve regeneration by analysis of the motor behavior tests, EMG, hematological(AST, ALT, WBC), histological and immunological changes. Rats were tested at modified Tarlov test at the 1st, 2nd, 3rd, 4th day, and Motor behavior test at 1st, 3rd, 7th, 14th, 21st day. Results : Results are as follows. 1. All the experimental groups were improved compared with control group in the motor behavior tests including Tarlov test, Basso-Beattle-Bresnahan locomotor rating scale, modified inclined plane test, open field test, grid walk test and narrow beam test. Especially Experimental III was improved significantly among other groups. 2. In EMG test, H wave appeared weak only in Experimental III. And M wave was increased significantly in Experimental III. 3. All the experimental groups were significantly decreased compared with control group in serum AST, serum ALT and serum WBC tests. 4. significantly decreased in Tumor Necrosis Factor-${\alpha}$ test compared with the first day of SCI. 5. Muscle contraction and denaturation of all the experimental groups were inhibited in histological observations of gastrocnemius muscle. Especially, those of experimental III was more effective. 6. NGF and BDNF of spinal cord gray matter in all the experimental groups were increased compared with control group. Especially, those of experimental III was more effective. Conclusions : As above, it can be suggested that Yanghyuljanggeungunbo-tang(Yangxuezhuangjinjianbu-tang) and Cervi Cornu Parvum pharmaco-acupuncture may improve motor behavior, EMG, hematological, histological and immunological findings in Spinal Cord Injury(SCI)-induced rats. Especially, effects will be somewhat better in combination of these two treatments.