• Title/Summary/Keyword: 1/f fluctuation

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1/f-LIKE FREQUENCY FLUCTUATION IN FRONTAL ALPHA WAVE AS AN INDICATOR OF EMOTION

  • Yoshida, Tomoyuki
    • Proceedings of the Korean Society for Emotion and Sensibility Conference
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    • 2000.04a
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    • pp.99-103
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    • 2000
  • There are two approaches in the study of emotion in the physiological psychology. The first is to clarify the brain mechanism of emotion, and the second is to evaluate objectively emotions using physiological responses along with our feeling experience. The method presented here belongs to the second one. Our method is based on the "level-crossing point detection" method. which involves the analysis of frequency fluctuations of EEG and is characterized by estimation of emotionality using coefficients of slopes in the log-power spectra of frequency fluctuation in alpha waves on both the left and right frontal lobe. In this paper we introduce a new theory of estimation on an individual's emotional state by using our non-invasive and easy measurement apparatus.

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Experimental investigation on effect of ion cyclotron resonance heating on density fluctuation in SOL at EAST

  • Li, Y.C.;Li, M.H.;Wang, M.;Liu, L.;Zhang, X.J.;Qin, C.M.;Wang, Y.F.;Wu, C.B.;Liu, L.N.;Xu, J.C.;Ding, B.J.;Lin, X.D.;Shan, J.F.;Liu, F.K.;Zhao, Y.P.;Zhang, T.;Gao, X.
    • Nuclear Engineering and Technology
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    • v.54 no.1
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    • pp.207-219
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    • 2022
  • The suppression of high-intensity blob structures in the scrape-off layer (SOL) by ion-cyclotron range of frequencies (ICRF) power, leading to a decrease in the turbulent fluctuation level, is observed first in the Experimental Advanced Superconducting Tokamak (EAST) experiment. This suppression effect from ICRF power injection is global in the whole SOL at EAST, i.e. blob structures both in the regions that are magnetically connected to the active ICRF launcher and in the regions that are not connected to the active ICRF launcher could be suppressed by ICRF power. However, more ICRF power is required to reach the full blob structure suppression effect in the regions that are magnetically unconnected to the active launcher than in the regions that are magnetically connected to the active launcher. Studies show that a possible reason for the blob suppression could be the enhanced Er × B shear flow in the SOL, which is supported by the shaper radial gradient in the floating potential profiles sensed by the divertor probe arrays with increasing ICRF power. The local RF wave power unabsorbed by the core plasma is responsible for the modification of potential profiles in the SOL regions.

Effect of Carbon Dioxide Concentration on Malate and Titratable Acidity in Pereskia aculeata and Kalanchoe rosea

  • Park Shin Young;Furukawa Akio
    • Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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    • v.2 no.2
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    • pp.109-114
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    • 1998
  • The induction of crassulacean acid metabolism(CAM) characterized by day/night acid fluctuation was investigated in leaves from 10 days exposure to elevated $CO_2$ concentration(1,000 ${\mu}L\;L^{-1}CO_2).$ For Pereskia aculeata, have $C_3-like$ gas exchange pattern in well watered condition and shift into CAM-like in water stress, showed a more typical CAM-like diurnal acid fluctuation. Whereas the massive diurnal fluctuation of acidity in typical CAM of Kalanchoe rosea was declined. The effect of short-term exposure to various concentrations of $CO_2$ on titratable acidity in P. aculeata and K. rosea was also investigated. To investigate the response of various $CO_2$ concentrations, four different $CO_2$ levels(350, 700, 1,000 and 1,500 ${\mu}L\;L^{-1})$ were imposed for 24hr and measured the titratable acidity at 06:00, when the acidity was maximum, and 14:00, when the acidity was minimum. The accumulation of acid in P. aculeata was enhanced markedly by higher concentration of $CO_2,$ while the level of acidity in f rosea did not highly respond to $CO_2.$ A notable difference between P. aculeata and K. rosea was the response of de-acidification to a higher concentration of $CO_2$ Increasing with $CO_2,$ the degree of do-acidification of P. auleata was increased while that of K. rosea was depressed.

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The Variation of Nutural Population of Pinus densiflora S. et Z. in Korea -Change of variance due to number of family as sample size to affirm the population and family variations- (소나무 천연집단(天然集團)의 변이(變異)에 관(關)한 연구(硏究)(IV) -집단간(集團間) 및 가계간분산(家系間分散) 추정(推定)에 영향하는 가계수(家系數)에 대하여-)

  • Yim, Kyong Bin;Kwon, Ki Won;Lee, Kyong Jae
    • Journal of Korean Society of Forest Science
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    • v.35 no.1
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    • pp.39-46
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    • 1977
  • In the analysis of variance between population and between individual trees (families), the fluctuation of values of variances due to sample size, (number of family) was analysed by two different designs, i.e. 2-level nested design with equal sample size and randomized complete block design. The variables were seedling heights and root calipers of 1-0 and 1-1 seedlings of Pinus densiflora S. et Z. The details of three natural stands and their progeny characters were presented in previous reports. 1. In nested design analysis. increase of sample size resulted the decrease of F-values among families in general, however, the F-values among populations showen the increasing tendency. The smaller the sample size, the larger the F-values fluctuation was resulted in general. At the point of beyond sample size 10, however, the fluctuation become to be stabilized. The F-value fluctuation seemed to be more in the case of analysis with random sampling method than with sequentially accumulated sampling method. And also such a tendency was more obvious in smaller sample size than in large one. 2. In R.C.B.D. analysis, the sample size to affirm the family variation was smaller than that for population variations.

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Analysis on the Use Behavioral Patterns and Use Fluctuation over the Tong-Ch′on Amusement Park (동촌유원지의 이용실태 및 변동분석)

  • 김용수;임원현
    • Journal of the Korean Institute of Landscape Architecture
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    • v.15 no.1
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    • pp.17-37
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    • 1987
  • The purpose of this study is to establish more rational and practical planning theory for amusement park. It analyze and consider the fluctuation of people who come and use the Tong-Ch'on amusement park. The results drawn from this reserch work are as follows; 1. The main visitors of the Tong-Ch'on amusement park are students in their twenties and thirties, and people whose incomes are below 300,000 Won a month. The purpose of visit is for a rest rather than for amusement and user prefer summer, while the user is so rare in wintertime. Those phenomena observed are somewhat different from the real purpose of a amusement park which is on purpose to make profits by offering entertainments to the users. So planner should pay attention to the three points. They are varieties, seasonable diversification and fantastic character of facilties, in the amusement park. 2. The access time of the Tong-Ch'on amusement park was 41 minutes, the use frequency was 4 times a year and resident time was 164 minutes. The relationship of the three factors are as follows; log Y(F) =1.7832-0.0277(A.T) R$^2$=0.75 Y(R. F)=31.8885+3.3217(A.T) R$^2$=0.53 Y(R. T)=224.8959-87.8309 1og(F) R$^2$=0.38 F;Use frequency(time/year) A.T;Access Time(minute) R.T;Resident Time(minute) 3. In the choice of space, there were much differences according to tole user's age, job, degree of education, companion type and purpose of use. 4. There are considerable correlation between use fluctuation and some factors. The factors are season(summer, winter) as a time, temperature, cloud amount, duration of sunshine, weather(rainy-day) as a climate and a day of the week(weekday, holiday) as a social system. The important variables are temperature, cloud amount, duration of sunshine and a day of the week(weekday, holiday) to estimate the user of amusementpark. 5. 1 can reduce the following two types of regression models. 1) log$\sub$e/ Y1 = 6.9114 + 0.l135 TEM + 0.00002 SUN -0.4068W1 + 0.4316 W3 (R$^2$= 0.94) 2) log$\sub$e/ Y2 = 7.2069 + 0.l177 TEM - 0.0990 CLO + 0.4880 W3 (R$^2$=0.95) Y; Number of User TEM; Temperature CLO; Amount of cloud SUN; Duration of Sunshine W1; Weekday W3; Holiday Those model is in order to estimate the user for management of Tong-Ch'on amusement park and use on the computation of facility sloe for reconstruction. Besides the amusement park, city park and outdoor recreation area could estimate of user through this method. But, I am not sure about the regression models because I did not apply the regression models to the other amusement park, city Park or outdoor recreation area. Therefore, I think that this problem needs to be studied on in the future.

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$MgF_2$ AR Coating 두께에 따른 CIGS Cell Performance 변화

  • Kim, Ju-Hui;Lee, Gyu-Seok;Jo, Dae-Hyeong;Choe, Hae-Won;Kim, Je-Ha
    • Proceedings of the Korean Vacuum Society Conference
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    • 2011.08a
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    • pp.373-373
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    • 2011
  • $Cu(In,Ga)Se_2$(CIGS) 박막 태양전지는 Chalcopyrite계 박막 태양전지로 Cu, In, Ga, Se 각 원소의 조성을 적절히 조절하여 박막을 성장시킨다. 성장시킨 CIGS 박막은 광흡수계수가 105cm-1로 다른 물질 보다 뛰어나고 직접 천이형 반도체로서 얇은 두께로도 고효율의 박막 제작이 가능하다. 얇은 두께로도 충분히 빛의 흡수가 가능하지만, cell 표면 반사에 의한 광 손실은 cell 효율을 떨어뜨리게 된다. 본 연구에서는 CIGS 박막 태양전지의 광 흡수 향상을 위해 굴절률이 1.86인 ITO 위에 ITO보다 굴절률이 작은 $MgF_2$ (n=1.377) [1]를 80, 100, 120, 140 nm로 증착하여 $MgF_2$/Al/Ni/ITO/i-ZnO/CdS/CIGS/Mo/SLG 시료를 제작하고, optical reflectance, Quantum Efficiency를 이용하여 분석하였다. optical reflectance 분석 결과, $MgF_2$ AR coating을 한 경우, 두께가 두꺼워짐에 따라 광 반사도가 감소하는 경향을 보였다. 또한 AR coating 두께가 커짐에 따라 fluctuation이 점점 커지며, 파형이 장파장 쪽으로 shift하는 것을 관찰 할 수 있었다. Quantum efficiency (QE)를 분석한 결과 $MgF_2$ AR coating 할 경우, 측정된 대부분의 파장에서 QE가 향상되는 것을 확인할 수 있었다. 하지만 AR coating 두께에 따른 변화는 뚜렷한 차이를 보이지 않았다. AR coating 결과, JSC가 증가하여 efficiency가 향상되는 것을 확인 할 수 있다. 그러나 $MgF_2$ AR coating 80~140 nm 범위에서 cell 효율 변화의 뚜렷한 차이는 관찰할 수 없었다.

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Effects of Inflow Fluctuation on the Removal Efficiency in Low Strength Sewage Treatment using Sequencing Batch Reactor Process during Rainfall (강우시 저농도 고수리부하가 회분식 반응조 제거효율에 미치는 영향)

  • Oa, Seongwook;Kim, Geonha;Son, Bongho
    • Journal of Korean Society on Water Environment
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    • v.22 no.1
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    • pp.91-96
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    • 2006
  • Many small scale Sewage Treatment Plants (STPs) are currently being constructed at many rural areas. The STPs in rural area suffer from low concentration and large inflow quantity fluctuation during wet weather mainly due to illicit combined sewer system. Sequencing Batch Reactor (SBR) is a process effectively coping with these obstacles. The main objective of this study was to evaluate SBR with high hydraulic loading and low inflow concentration. The operating conditions tested were: organic loading rate = $0.17-0.42KgBOD/m^3/d$, hydraulic loadings = $12.1-61.5m^3/m^2/d$, average MLSS concentration = 2500 mg/L, F/M ratio = 0.026-0.17 KgBOD/Kg MLSS, HRT = 9-12 hr HRT, and SRT = 5.6-33.6 days. Organic loading rate on SBR did not impact significantly on BOD and SS removal efficiencies. To increase treatment efficiencies, low hydraulic loading rate with low concentration was required. The results suggested that low influent concentration with high inflow rates during wet weather requires extended time for settling.

Predictability of the f/g time series

  • Cho, Il-Hyun;Kim, Yeon-Han;Cho, Kyung-Seok;Park, Young-Deuk
    • The Bulletin of The Korean Astronomical Society
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    • v.36 no.1
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    • pp.40.1-40.1
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    • 2011
  • Large solar flares are associated with various aspects of space weather effects. Numerous attempts have been made to predict when the solar flare will be occurred mainly based on the configuration of the magnetic field of its flaring site. We analyze the time series of f/g which indicates a representative measure of the sunspot complexity to see whether it shows a possibility to be predicted without huge amounts of observation. Two kinds of analysis results are presented. One is from its power spectrum giving that there's no significantly persistent periodicity within a few days. Its de-trended fluctuation shows the Hurst exponent larger than 0.5 implying that the f/g time series has a long-term memory in time scales less than 10 days.

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A Measurement Error Correction Algorithm of Road Image for Traveling Vehicle's Fluctuation Using V.F. Modeling (V.F. 모델링을 이용한 주행차량의 진동에 대한 도로영상의 계측오차 보정 알고리듬)

  • Kim Tae-Hyo;Seo Kyung-Ho
    • Journal of Institute of Control, Robotics and Systems
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    • v.12 no.8
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    • pp.824-833
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    • 2006
  • In this paper, the image modelling of road's lane markings is established using view frustum(VF) model. From this model, a measurement system of lane markings and obstacles is proposed. The system also involve the real time processing of the 3D position coordinate and the distance data from the camera to the points on the 3D world coordinate by virtue of the camera calibration. In order to reduce their measurement error, an useful algorithm for which analyze the geometric variations due to traveling vehicle's fluctuation using VF model is proposed. In experiments, without correction, for instance, the $0.4^{\circ}$ of pitching rotation gives the error of $0.4{\sim}0.6m$ at the distance of 10m, but the more far distance cause exponentially the more error. We con finned that this algorithm can be reduced less than 0.1m of error at the same condition.

Direct Simulation of Acoustic Sound by the Finite Difference Lattice Boltzmann Method (차분격자볼츠만법에 의한 유체음의 직접계산)

  • Kang, Ho-Keun;Ro, Ki-Deok;Lee, Young-Ho
    • Proceedings of the KSME Conference
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    • 2003.04a
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    • pp.1827-1832
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    • 2003
  • In this research, the simulation method for acoustic sounds by a uniform flow around a two-dimensional circular cylinder by using the finite difference lattice Boltzmann model is explained. To begin with, we examine the boundary condition which determined with the distribution function $f_i^{(0)}$ concerning with density, velocity and internal energy at boundary node. Very small acoustic pressure fluctuation, with same frequency as that of Karman vortex street, is compared with the pressure fluctuation around a circular cylinder. The acoustic sound' propagation velocity shows that acoustic approa ching the upstream, due to the Doppler effect in the uniform flow, slowly propagated. For the do wnstream, on the other hand, it quickly propagates. It is also apparently the size of sound pressure was proportional to the central distance $r^{-1/2}$ of the circular cylinder. The lattice BGK model for compressible fluids is shown to be one of powerful tool for simulation of gas flows.

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