• Title/Summary/Keyword: beta (${\beta}$) wave

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Profile Control Using RF Wave Heating in KT-2 Tokamak

  • Ju, M.H.;Hong, B.G.;Kim, S.K.
    • Proceedings of the Korean Nuclear Society Conference
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    • 1996.05d
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    • pp.443-448
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    • 1996
  • In this paper, the 100 % non-inductive current drive scenarios are addressed for the steady-state operation on KT-2 tokamak, with the profile control using fast wave and lower hybrid wave as the external tools. Considering the stability, the well-aligned current profiles with a reversed-shear and $q_{min}$ > 2.0 has been favor-able in high ${\beta}_{p}$ plasma, together with a possibly higher bootstrap current fraction. Therefore, the effects of the auxiliary heating power profile on the control of MHD favorable current profile are evaluated in detail.

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The Effect of Non-ivasive Baihui($GV_{20}$) Point Stimulus by 'Dong Chu Gold Chim' on Electroencephalogram (동추금침(東樞金鍼)에 의한 비침습적 백회혈(百會穴) 자극이 뇌파에 미치는 영향)

  • Ma, Jeung-Hun;Han, Chang-Hyun;Park, Soo-Jin;Choi, Woo-Suk;Lee, Sang-Nam;Park, Ji-Ha
    • Journal of Acupuncture Research
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    • v.27 no.1
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    • pp.87-100
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    • 2010
  • Background : Recently a discussion about Qi including a study about the effect or the theory of acupuncture is getting prevailing in various angles. In most of studies about acupuncture stimulus, 'Filiform acupuncture'(毫鍼) is used. A study about Nine kinds of acupuncture(九鍼), except 'Filiform acupuncture'(毫鍼) has not been reported yet, and there is no study about using a special acupuncture made for controling Qi either. Objectives : 'Dong Chu Gold Chim(DCG-chim, 東樞金鍼)' can be used for patients who are scared of a pain because it is a medical Qi-gong tool and non-invasive stimulus one. To assess a effect of Qi-gong operation using DCG-chim objectively Methods : The present study was performed to elucidate the effects of DCG-chim stimulation of an acupuncture point Baihui($GV_{20}$) on the Electroencephalogram(EEG). Twenty healthy subject were treated with DCG-chim one time accompanied by the light and vertical pressure and EEG were measured during five minutes for three times (before, during and after treatment). The EEG results of DCG-chim treatment were compared with those of 'Filiform acupuncture(毫鍼)'. Results : EEG power spectra changed significantly after both kind of acupuncture stimulation. Significant increase of $\alpha$ wave and decrease of $\beta$ wave were observed but interestingly, Mid-$\beta$ and SMR of $\beta$ wave which mean the state of concentration were increased with statistically significant. According to these results, DCG-chim stimulation of Baihui($GV_{20}$) seems to lead to relaxation with antianxietic effect and improvement of concentration at the same time. Conclusions : It would be expected that the doctor can apply DCG-chim for treating anxiety, tension, symptom caused by stress and also can use it clinically for patients who have needlphopia or children as a non-invasive procedure. It is suggested that additional studies about the effect of DCG-chim on other acupuncture points and comparison study about the effect of DCG-chim with those of the finger-pressure treatment using other tool should be done in the future.

Comparison between quasi-linear theory and particle-in-cell simulation of solar wind instabilities

  • Hwang, Junga;Seough, Jungjoon;Yoon, Peter H.
    • The Bulletin of The Korean Astronomical Society
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    • v.41 no.1
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    • pp.47.2-47.2
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    • 2016
  • The protons and helium ions in the solar wind are observed to possess anisotropic temperature profiles. The anisotropy appears to be limited by various marginal instability conditions. One of the efficient methods to investigate the global dynamics and distribution of various temperature anisotropies in the large-scale solar wind models may be that based upon the macroscopic quasi-linear approach. The present paper investigates the proton and helium ion anisotropy instabilities on the basis of comparison between the quasi-linear theory versus particle-in-cell simulation. It is found that the overall dynamical development of the particle temperatures is quite accurately reproduced by the macroscopic quasi-linear scheme. The wave energy development in time, however, shows somewhat less restrictive comparisons, indicating that while the quasi-linear method is acceptable for the particle dynamics, the wave analysis probably requires higher-order physics, such as wave-wave coupling or nonlinear wave-particle interaction. We carried out comparative studies of proton firehose instability, aperiodic ordinary mode instability, and helium ion anisotropy instability. It was found that the agreement between QL theory and PIC simulation is rather good. It means that the quasilinear approximation enjoys only a limited range of validity, especially for the wave dynamics and for the relatively high-beta regime.

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Evaluation of Ultrasonic Nonlinear Characteristics in Artificially Aged Al6061-T6 (인공시효된 Al6061-T6의 초음파 비선형 특성 평가)

  • Kim, Jongbeom;Lee, KyoungJun;Jhang, Kyung-Young;Kim, ChungSeok
    • Journal of the Korean Society for Nondestructive Testing
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    • v.34 no.3
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    • pp.220-225
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    • 2014
  • Generally, the nonlinearity of ultrasonic waves is measured using a nonlinear parameter ${\beta}$, which is defined as the ratio of the second harmonic's magnitude to the power of the fundamental frequency component after the ultrasonic wave propagates through a material. Nonlinear parameter ${\beta}$ is recognized as an effective parameter for evaluating material degradation. In this paper, we evaluated the nonlinear parameter of Al6061-T6 which had been subjected to an artificial aging heat treatment. The measurement was using the transmitted signal obtained from contact-type transducers. After the ultrasonic test, a micro Vickers hardness test was conducted. From the result of the ultrasonic nonlinear parameter, the microstructural changes resulting from the heat treatment were estimated and the hardness test proved that these estimates were reasonable. Experimental results showed a correlation between the ultrasonic nonlinear parameter and microstructural changes produced by precipitation behavior in the material. These results suggest that the evaluation of mechanical properties using ultrasonic nonlinear parameter ${\beta}$ can be used to monitor variations in the mechanical hardness of aluminum alloys in response to an artificial aging heat-treatment.

Molecular Structural Properties of Chindo Black Rice Starch (진도산 검정쌀 전분의 분자구조적 특성)

  • Park, Jong-Hoon;Oh, Keum-Soon;Kang, Kil-Jin;Kim, Kwan
    • Applied Biological Chemistry
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    • v.43 no.4
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    • pp.241-246
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    • 2000
  • In order to investigate structural properties of Chindo black rice(grown in Chindo, Chonnam) starch and its amylopectin, Chindo black rice was investigated in comparison to Shinsun waxy rice. The maximum absorbance wave and intrinsic viscosity of Chindo black rice starch and Shinsun waxy rice starch were 523 nm, 521 nm and 183 ml/g, 178 ml/g, respectively. ${\beta}-amylolysis$ limit(%) of Chindo black rice and Shinsun waxy rice starch were 62.8% and 60.3%, respectively. Chindo black rice was determined to be a waxy rice due to the results of iodine reaction and elution profile on Sephroce CL-2B. The chain of amylopectins in Chindo black rice distributed fraction 1$(F_1)$ of above degree of polymerization$({\overline{DP}})$ 55, fraction 2$(F_2)$ of ${\overline{DP}} $40{\sim}50$ and fraction 3$(F_3)$ of ${\overline{DP}} $15{\sim}20$, and the ratio of $F_3$ to $F_2$ for Chindo black rice was higher than that for Shinsun waxy rice. The super long chain of amylopectin in Chindo black rice was consisted much more than that of Shinsun waxy rice. ${\beta}-limit$ dextrins in Chindo black rice amylopectin distributed $F_1$ of above ${\overline{DP}} 55, $F_2$ of ${\overline{DP}} $30{\sim}45$ and $F_3$ of ${\overline{DP}} $10{\sim}20$. Little difference was shown between elution patterns of the pullulanase treated ${\beta}-limit$ dextrins of Chindo black rice amylopectin and Shinsun waxy rice amylopectin. These results suggest that Chindo black rice starch was similar to Shinsun waxy rice starch.

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The efficiency Analysis of study using brainwave measurement device (Biopac 뇌파측정 장치를 이용한 학습의 효율성 분석)

  • An, Young-Jun;Lee, Chung-Heon;Park, Mun-Kyu;Ji, Hoon;Lee, Dong-Hoon
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2015.05a
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    • pp.951-953
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    • 2015
  • Learning for thinking says the behavior of the organism changes as a result of practice or experience. It is very difficult to identify focusing ability objectively when students study. But, brain of the body is not so. EEG signal means continuously electric records of brain potential variation between two points on the scalp when brain activities take place. In types of EEG, there are delta(0~4Hz), theta(4~8Hz), alpha(8~13Hz), beta(13~30Hz) and gamma waves(30~50Hz). SMR waves and Mid-beta waves appear when focused for studying. Part for the most influence on concentrating reported that Mid-beta waves. In relation to brain activities, EEG has been actively researched for evaluating brain focus index system during learning and study. So, By using Biopac system for this study, measured brain wave was converted into FFT for extracting Mid-beta domain signals that are related to learning after giving focus invoked subjects to a small number of people. When concentrating, we measured the change in the power of the Mid-beta frequency domain and presented a correlation. Based on these results, we analyzed whether students are concentrated objectively on learning or not. and hope to offer more efficient learning method.

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The Effect of Daytime Exercise Load on Sleep Structure and the Secretion of Growth Hormone, Testosterone, Cortisol, $\beta$-endorphin during Sleep (주간 운동량이 수면구조와 수면 중 Growth Hormone, Testosterone, Cortisol, $\beta$-endorphin의 분비에 미치는 영향)

  • Kim, Jin-Hang;Hong, Seung-Bong;Yi, Ji-Yeong;Cho, Keun-Chong
    • Sleep Medicine and Psychophysiology
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    • v.6 no.2
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    • pp.116-125
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    • 1999
  • Objectives: The purpose of this study is to investigate the effect of exercise load on sleep structure and stress hormone secretion during sleep. Methods: Five male physical education students were included in this study after giving their written, informed consents in the Research Institute for Sports Science at the University of Hanyang. All subjects have performed for at least 3 years in a regular aerobic exercises such as football, basketball, and running. The subjects were divided into three groups ; NOE(non-exercise), MDE(middle duration exercise), LDE(long duration excercise). MDE group maintained a total of 120 min exercise, and LDE group maintained a total of 300 min exercise by football, basketball or badminton. All subjects were acclimatized to the experimental sleep condition by spending one night under expermental conditions, including the placement of an intravenous catheter. During the subsequent night(24:00-08:00), somnopolygraphic sleep recordings were obtained, and blood for measuring growth hormone, cortisol, testosterone, and $\beta$-endorphin was collected every 120 min throughout the night. Blood samples were obtained from prominent forearm veins of subjects. Then, the samples were immediately placed in ice and centrifuged within 10 min at 3000 rpm at $4^{\circ}C$. Statistical analyses were performed using the SPSS/$PC^+$. Data were analyzed by one-way ANOVA with repeated measures. Results: No significant differences among groups were observed in sleep latency, total sleep time, stage 2 sleep, and slow wave sleep. However, daytime exercise produced significant changes in stage 1 sleep, REM sleep, stage 2 sleep latency, REM sleep latency and sleep efficiency. Stage 1 sleep, stage 2 sleep latency, and REM sleep latency significantly increased in LDE compared to those of NOE and MDE groups. But the amount of REM sleep significantly decreased in LDE. Sleep efficiency of MDE was higher than those of NOE and LDE. The blood concentrations of growth hormone, testosterone, and cortisol during night sleep were significantly lower in LDE than in NOE. $\beta$-endorphin concentrations in blood during night sleep were not different among groups. Conclusion: The daytime exercise load was significantly related to sleep structure and stress hormone secretion during night sleep. Long duration exercise showed a harmful effect on sleep structure and hormone secretion. However, middle duration exercise had a beneficial effect on sleep structure and hormone secretion during sleep.

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뇌파의 감성자극에 의한 변화

  • 황민철;조희관;김진호;김철중
    • Proceedings of the ESK Conference
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    • 1997.04a
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    • pp.3-9
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    • 1997
  • EEG(electroencephalogram) is attempted to determination of human emotion. Ten university students were participated in this study. Ten auditory stimuli were presented for a subject to evoke emotion. Data homogeneity according to brain local area and basic mechanism of relative variation for combinational delta, theta, alpha and beta waves were analyzed. As the result, the local area characterized by factor analysis and the relative variation of alpha-delta wave can be considered as the determinants of human emotion.

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Sleep Stage Analysis by using Polysomnogram and Spindle Wave (다원수면검사와 방추파에 의한 수면단계 분석)

  • 김원식;박세진;김진선;김건흠
    • Proceedings of the ESK Conference
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    • 1997.10a
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    • pp.386-390
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    • 1997
  • SAC 847 컴퓨터를 통해서 뇌파를 기본으로 턱과 다리의 근전도, 몸의 뒤척임, 심전도, 혈중 산소 농 도, 안전도 등을 동시에 기록하는 다원수면검사(polysomnogram)를 전자기가 차폐된 수면실에서 실시하 였고 수면단계기록 국제기준에 의한 수면단계와 최근 새롭게 제시되고 있는 수면의 경과에 따른 수면방 추파(sleep spindle)의 변동추적에 의한 수면단계 판정방법을 비교 분석하였다. 또한, 수면경과에 따른 .beta. .alpha. .theta. .delta. 파형의 발생빈도를 제시하고 평가하였다. 이러한 수면단계 분석은 종합 수면생리신호의 일환으로 인간공학적인 쾌적침대개발에 활용될 수 있을 것이다.

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A Study on mobile based EEG display and device development (모바일기반으로한 EEG표시 및 장치개발에 관한 연구)

  • Lee, Chung-Heon;Kim, Gyu-Dong;Hong, Jun-Eui;Kwon, Jang-Woo;Lee, Dong-Hoon
    • Proceedings of the IEEK Conference
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    • 2009.05a
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    • pp.145-147
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    • 2009
  • This research measures EEG signals which are generating on head skin and extracts brain concentration level related with brain activity. We have developed concentration wireless transmission system by displaying this EEG signal on PDA mobile device. The front head was used for measuring EEG signal and INA128 with TL084 and analog elements was used for measuring EEG signal, amplifying and filtering the signal. Measured analog EEG signals changed into digital signals by using ADC of PIC24FJ192 with 10bit resolution and 500Ks/s sampling rate. So The changed digital signals have transmitted to the PDA by using bluetooth. LabView 8.5 was also used for FFT transformation, frequency and spectrum analysis of the transferred EEG signal. As a result, $\alpha$ wave, $\beta$ wave, $\theta$ wave and $\delta$ wave were classified. we extracted the concentration index by adapting concentration extraction algorithm. This concentration index was transferred into PDA by wireless module and displaying.

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