• Journal of People, Plants, and Environment
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• v.22 no.2
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• pp.127-143
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• 2019

This study investigates the color stimuli of two varieties of foliage plants by extracting electroencephalogram, electrocardiogram and physiology activity data from 30 participants in their 50s or older. Changes in the physiological activity of subjects against six color stimuli were examined. The stimulus to real green plants 'Silver Queen' was set as the control group, and was compared with other groups including the stimulus to real 'Angel' plants and four stimuli to artificial colors (two color images and color schemes of the same green and red plants). Compared to the five groups, the relative theta power spectrum (RT) and the ratio of alpha to high beta (RAHB) increased in the subjects exposed to real green plants. This result demonstrates that the green plant ('Silver Queen') increases the stability, relaxation, and internal concentration of subjects in a proper state of awakening. The result of this experiment showed a statistically significant difference in the level of RT when subjects were exposed to the groups of real green and red plants. This finding indicates that the green plant increases internal concentration more than the red plant. RT and the relative low beta power spectrum (RLB) in the groups of natural colors were higher than the groups of artificial colors when subjects focused their mind on the two types of real plants. However, the level of relative mid beta power spectrum (RMB), ratio of SMR to theta (RST), ratio of mid beta to theta (RMT), relative high beta power spectrum (RHB), and spectral edge frequency 95% were higher when subjects were exposed to the photos and colors scheme of plants than when they were exposed to real plants. The subjects experienced more "comfortable" emotions when they were looking at plants with green colors. Overall, it is recommended to use the natural colors of real plants in places where which stability and relaxation are required. On the contrary, the artificial colors of plants such as their photos and color schemes are useful in places where a high level of concentration is required in a short period of time.

• Journal of Oriental Neuropsychiatry
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• v.16 no.2
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• pp.181-188
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• 2005

The purpose of this study is to investigate how much acupuncture treatment and autogenic training can affect to physical, mental relaxation through neurofeedback(Alpha/Theta training). I measured the numerical value of Alpha/H-Beta on the patient with facial tremor due to anxiety during acupuncture treatment and autogenic training, and when that patient wasn't relaxed I gave her feedback. The result shows that autogenic training is always more effective than aucupuncture in making the patient relaxed. On this case, the symptom was not much improved after having the treatments 10 times, but the frequency and intensity of the tremor decresed little. In according to the number of treatments, relaxtion didn't ascend regularly. I think it depends on the patient's condition or surroundings. I am unsatisfied I had only one case in this study and the number of treatments wasn't enough. In the future, much more clinical and statistical studies on herbal, musical, aroma therapies should be needed.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.22 no.3
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• pp.267-279
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• 1998

A numerical study was made of flow behind a circular cylinder in a uniform flow, where the cylinder was rotationally oscillated in time. The temporal behavior of vortex formation was scrutinized over broad ranges of the two externally specified parameters, i.e., the dimensionless rotary oscillating frequency (.110.leq. $S_{f}$.leq..220) and the maximum angular amplitude of rotation (.theta.$_{max}$=15 deg., 30 deg. and 60 deg.). The Reynolds number (Re= $U_{{\inf}D}$.nu.) was fixed at Re=110. A fractional-step method was utilized to solve the Navier-Stokes equations with a generalized coordinate system. The main emphasis was placed on the initial vortex formations by varying $S_{f}$ and .theta.$_{max}$. Instantaneous streamlines and pressure distributions were displayed to show the vortex formation patterns. The vortex formation modes and relevant phase changes were characterized by measuring the lift coefficient ( $C_{L}$) and the time of negative maximum $C_{L}$( $t_{-C}$$_{Lmax}$) with variable forcing conditions.s.tions.s.s.s.

• Earthquakes and Structures
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• v.1 no.4
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• pp.411-425
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• 2010

The effect of dead loads on dynamic responses of uniform elastic beams is examined by means of a governing equation which takes into account initial bending stress due to dead loads. First, the governing equation of beams which includes the effect of dead loads is briefly presented from the author's paper (Takabatake 1990). In the formulation the effect of dead loads is considered by strain energy produced by conservative initial stresses produced by the dead loads. Second, the effect of dead loads on dynamical responses produced by live loads in simply supported beams and clamped beams is confirmed by the results of numerical computations with the Galerkin method and Wilson-${\theta}$ method. It is shown that the dynamical responses, like dynamic deflections and bending moments produced by dynamic live loads, are decreased in a heavyweight beam when the effect of dead loads is included. Third, an approximate solution for dynamic deflections including the effect of dead loads is presented in closed-form. The proposed solution shows good in agreement with results of numerical computations with the Galerkin method and Wilson-${\theta}$ method. Finally, a method reflecting the effect of dead loads for dynamic responses of beams on the magnitude of live loads is presented by an example.

• Journal of Sensor Science and Technology
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• v.24 no.6
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• pp.392-397
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• 2015

Recently computer games have been widely spread. For the purpose of studying brain activities, EEG was measured during the computer game and analyzed in terms of channels and frequency bands. EEG data were obtained during the resting state and game immersion. Then the power spectra of alpha, beta and theta bands were computed. During game immersion, the ratio between theta / alpha could effectively differentiate between rest and game immersion. Changes in brain activity (26~53%) were observed in the parietal and occipital lobes. Interestingly, immersion shows different features compared to concentration. The state of game immersion could be detected. Therefore, it is possible to utilize the state of immersion as one of the game parameters or to generate a control signal that may be used to provide a warning message or abort the game when the situation of the excessive indulgence in the game reaches. EEG can be applied as smart interface for computer game.

• Journal of the Korean Electrochemical Society
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• v.6 no.2
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• pp.119-129
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• 2003

The Langmuir adsorption isotherms of the over-potentially deposited hydrogen (OPD H) fur the cathodic $H_2$ evolution reaction (HER) at the poly-Au and $Rh|0.5M\;H_2SO_4$ aqueous electrolyte interfaces have been studied using cyclic voltammetric and ac impedance techniques. The behavior of the phase shift $(0^{\circ}{\leq}{-\phi}{\leq}90^{\circ})$ for the optimum intermediate frequency corresponds well to that of the fractional surface coverage $(1{\geq}{\theta}{\geq}0)$ at the interfaces. The phase-shift profile $({-\phi}\;vs.\;E)$ for the optimum intermediate frequency, i.e., the phase-shift method, can be used as a new electrochemical method to determine the Langmuir adsorption isotherm $({\theta}\;vs.\;E)$ of the OPD H for the cathodic HER at the interfaces. At the poly-Au|0.5M $H_2SO_4$ aqueous electrolyte interface, the equilibrium constant (K) and the standard free energy $({\Delta}G_{ads})$ of the OPD H are $2.3\times10^{-6}$ and 32.2kJ/mol, respectively. At the poly-Rh|0.5M $H_2SO_4$ aqueous electrolyte interface, K and ${\Delta}G_{ads}$ of the OPD H are $4.1\times10^4\;or\;1.2\times10^{-2}$ and 19.3 or 11.0kJ/mol depending on E, respectively. In contrast to the poly-Au electrode interface, the two different Langmuir adsorption isotherms of the OPD H are observed at the poly-Rh electrode interface. The two different Langmuir adsorption isotherms of the OPD H correspond to the two different adsorption sites of the OPD H on the poly-Rh electrode surface.

• Journal of the Institute of Electronics and Information Engineers
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• v.50 no.10
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• pp.217-228
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• 2013

In this paper, the brain function in relation with human's visual attention was investigated by means of coherence and bicoherence methods. Throughout experimentation with attentional visual stimulus ERP (Event Related Potential) data and synthesized simulated data with different combinations of parameters, it is demonstrated that bicoherence and coherence can be useful to reveal the phase synchronies between different frequency bands at fixed scalp location, and between different scalp locations at fixed frequency band, respectively. Both methods are also affected by time interval from the onset, and the level of white noise added. The phase coupled relationships among ${\Theta}$, ${\delta}$, and ${\alpha}$ bands, and between frontal and central lobes were observed for attentional tasks, while those were little observable for inattentional tasks, which can show brain's functional spatio-spectral differences associated with human's attention.

• Progress in Superconductivity
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• v.5 no.1
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• pp.75-79
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• 2003

YBCO films were deposited with various thicknesses from 100nm to 1.6$\mu\textrm{m}$ on single crystal $SrTiO_3$ substrates by pulsed laser deposition (PLD). The effects of different deposition conditions, especially different deposition rates by means of changing the pulsed laser frequency up to 200Hz, on the J$_{c}$ value were studied. For YBCO film with the thickness of 200nm, the $J_{c}$ value of $2.1MA/\textrm{cm}^2$ has been achieved under the high deposition rate of 3.2nm/s (190nm/min). The $J_{c}$ can be maintained greater than $1M/\textrm{cm}^2$ with the thickness less than 1$\mu\textrm{m}$. The X-ray analysis was used to examine the texture, crystallization and surface quality. The SEM was employed to analyze the surface of YBCO, and it was shown the surface of YBCO film became rougher with increasing the thickness. There were many large singular outgrowths and networks of outgrowths on the surface of YBCO films which lowered the density of thick YBCO film. The outgrowth network was probably the a-axis YBCO corresponding to XRD $\theta$-2$\theta$scan and $\chi$-scan which were used to characterize a-axis orientation of YBCO film. The reason for J$_{c}$ declining with increasing the thickness was studied and discussed.sed.

• The Korean Journal of Physiology and Pharmacology
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• v.13 no.3
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• pp.147-151
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• 2009

Repeated psychostimulants induce electroencephalographic (EEG) changes, which reflect adaptation of the neural substrate related to dopaminergic pathways. To study the role of dopamine receptors in EEG changes, we examined the effect of apomorphine, the dopamine D1 receptor antagonist, SCH-23390, and the D2 receptor antagonist, haloperidol, on EEG in rats. For single and repeated apomorphine treatment groups, the rats received saline or apomorphine for 4 days followed by a 3-day withdrawal period and then apomorphine (2.5 mg/kg, i.p.) challenge after pretreatment with saline, SCH-23390, or haloperidol on the day of the experiment. EEGs from the frontal and parietal cortices were recorded. On the frontal cortex, apomorphine decreased the power of all the frequency bands in the single treatment group, and increased the theta (4.5 ${\sim}$ 8 Hz) and alpha (8 ${\sim}$ 13 Hz) powers in the repeated treatment group. Changes in both groups were reversed to the control values by SCH-23390. On the parietal cortex, single apomorphine treatment decreased the power of some frequency bands, which were reversed by haloperidol but not by SCH-23390. Repeated apomorphine treatment did not produce significant changes in the power profile. These results show that adaptation of dopamine pathways by repeated apomorphine treatment could be identified with EEG changes such as increases in theta and alpha power of the frontal cortex, and this adaptation may occur through changes in the D1 receptor and/or the D2 receptor.

• Weed & Turfgrass Science
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• v.7 no.2
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• pp.130-139
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• 2018

The colors of packaging of herbicides and non-selective herbicides on the market in Korea are defined as brown and red, respectively, according to the notification of RDA. The present study aimed to understand consumer's electroencephalographic (EEG) response when looking at brown and red colors of herbicide and non-selective herbicide packaging papers. The EEG cap was placed on the scalp of each participant (men and women, 10 to 20 years old) and white (control) - brown - white - red colors were sequentially displayed for 5 seconds using the computer monitor. The EEG was measured and statistical analysis was performed using SPSS. For the brown color of the herbicide, men showed a decrease in concentration and a distracting response due to a decrease in the ratio of mid beta to theta (RMT) and the spectral edge of frequency (SEF90). In women, an increase in the ratio of SMR to theta (RSMT) and the spectral edge frequency 50% of the alpha (ASEF) was observed in different brain regions and these EEG changes may enhance the relaxation, stabilization and awakening states of the brain. For the red color of the non-selective herbicide, ASEF increased psychological stability in men. In women, a decrease in absolute high beta (AHB) may associate with a decrease in attention state of the brain. Overall data of the present study clearly revealed that the colors of two herbicides showed significantly different EEG response and gender difference.