• Journal of the Korean Society of Safety
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• v.23 no.3
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• pp.65-70
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• 2008

Electroencephalogram(EEG) would be the most objective psychophysiological research technique on human errors though few research has been taken yet. This study aimed to get characteristics of human error while committing simple Odd-Ball tasks by utilizing the power spectrum technique of EEG data. Each experiment was composed of 3 tasks with different rules, and three young undergraduate students participated in this study as paid subjects. The result showed that subject and the interaction of subject and task factors were statistically significant on variation of power of $\alpha$ and $\beta$ bands which implied there would exist groups with homogeneity in their response. And though the variation of band powers due to task factors were not so great as to get statistical significance, it implied that the task requiring decoding process would be more strange to human beings than the task merely requiring psychological recall process.

• Journal of the Ergonomics Society of Korea
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• v.17 no.1
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• pp.1-9
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• 1998

The sensitivity of the emotion evoked visually by IAPS was attempted to be defined using EEG(electroencephalogram). Twenty university students were participated in this study. Their EEG was measured and analyzed in terms of frequency range such as delta, theta, alpha and beta wave. The results showed that alpha increased, but delta and beta decreased with positive emotional progress. Inter-variation between alpha and delta in F4 and beta variation in P3 were indicative of the evaluation sensitivity of human emotion.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.61 no.1
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• pp.55-58
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• 2012

By using EEG and HRV, subjects were estimated on their psychological and physiological reaction when reading psychrometric chart in 7 point century font, in an environmental test room in the condition of temperature 25[$^{\circ}C$], relative humidity 50[RH%], air current speed 0.02[m/sec], giving variation in illuminance to 0.1, 300, 600, 1000, 1300 and 1600[lux]. As a result, it was at 1300[lux] that absolute ${\alpha}$ wave, SMR, SDNN were most vitalized, and also both sides ${\alpha}$ wave asymmetry index, SEF50, HRT, stress and fatigue degree were at the lowest. It was found that a certain illuminance which minimizes psychological stress and fatigue degree while enhancing concentration and task achievement stably does exist.

• Journal of Biomedical Engineering Research
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• v.16 no.2
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• pp.157-166
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• 1995

The Electroencephalogram (EEG) and evoked potential (EP) t;ave widely been used for study of brain functions. The EEG and EP signals acquired from multi-channel electrodes placed on the head surface are often interfered by other relatively large physiological signals such as electromyogram (EMG) or electroculogram (EOG). Since these artifact-affected EEG signals degrade EEG mapping, the removal of the artifact-affected EEGs is one of the key elements in neuro-functional mapping. Conventionally this task has been carried out by human experts spending lots of examination time. In this paper a neural-network based classification is proposed to replace or to reduce human expert's efforts and time. From experiments, the neural-network based classification performs as good as human experts : variation of decisions between the neural network and human expert appears even smaller than that between human experts.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.62 no.1
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• pp.50-55
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• 2013

Subjects with 0.7[clo]'s amount of clothing were estimated on their thermal comfort, concentrativeness, heart rate variability, stress and fatigue degree when given variation in relative humidity to 30, 40, 50, 60, 70, and 80[RH%], in an environmental test room of temperature 25[$^{\circ}C$], illumination 1000[lux] and air velocity 0.02[m/sec], by using EEG, learning ability and HRV. At the result, it was at 50~60[RH%] of relative humidity that subject's thermal comfort and concentrativeness were at the highest while stress were at the lowest, and it was at 60[RH%] of relative humidity that heart rate variability was most stabilized. It was found that when temperature and humidity of the environmental test room are at 25[$^{\circ}C$] and 50~60[RH%], subject's productivity and psychological state are least affected.

• Proceedings of the IEEK Conference
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• 2002.06e
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• pp.289-292
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• 2002

In this study, we measure and analyzed variation of EEG signal by anesthesiologist progress step. In an experiment, the EEG signal was acquired and analyzed as 5 steps(prior surgical operation, during induction, surgical operation, awakening, posterior surgical operation). As a result, we confirm the anesthesiologist progress phase, concluded the possibility of anesthesia depth because using SEF and MF, and Delta ratio confirmed that can presume operating patient's consciousness state.

• Journal of the Korean Society of Safety
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• v.25 no.3
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• pp.123-130
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• 2010

Electroencephalogram(EEG) would be the most objective psychophysiological research technique on human errors though few research has been taken yet. This study aimed to get characteristics of human error while committing simple Odd-Ball tasks by utilizing the power spectrum technique of EEG data. Each experiment was composed of 3 tasks with different rules, and 8 young undergraduate students participated in this study as paid subjects. The result showed in the affirmative that subject and the interaction of subject and task factors were statistically significant on variation of $\alpha$ band power $P_{\alpha/(\alpha+\beta+\theta)}$ and $\beta$ band power $P_{\beta/(\alpha+\beta+\theta)}$, and that the former increasing in backward direction to Pz reflects compatibility whereas the latter increasing in forward direction to Fz reflects familiarity. Therefore it was coucluded that, since task 2 carried out in the present research requiring decoding process would be more difficult to human beings than the task merely requiring psychological recall process, task 1 and task 3 were classified into a homogenious group excluding task 2, and the ratio $\alpha$ band power to $\beta$ band power indicated enormous increase of $\alpha$ band power relative to $\beta$ band power in the cases of contra-lateral errors, especially in task 2.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.12 no.11
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• pp.1914-1922
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• 2008

In this paper, examined characteristics of EEG(electroencephalogram) variation when the stimulation was given to lung-wan(CV12), Shin-gwol(CV8) and Gwan-won(CV4) which were some of the acupuncture point, through indirect moxibustion and No stimulation. The EEG signals were measured before the stimulation, during the stimulation, and 1 hour after the stimulation. The measured time domain data were converted to the frequency domain data FFT(Fast Fourier Transform) and frequency power spectrum. Then the $\alpha,\beta,\delta$, and $\theta$ waves were analyzed for variation to the amplitude of vibration according to the stages of stimulation.

• The Research Journal of the Costume Culture
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• v.21 no.4
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• pp.535-545
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• 2013

The aim of this study was comparing measuring tools for detecting physical comfortness with variation of garment pressure. The measuring tools for detecting physical comfortness were EEG and survey questionnaire. Two low-pressure compressionwears and a commercial compressionwear (girdle) were tested. Results showed that the questionnaire survey well detected suffocation or motion comfortness. But it did not discrete the appropriate tightness of the compressionwears. The results of EEG analysis show that the absolute power of ${\alpha}$-wave value was elevated with the low-pressure compressionwears. It also showed lower stress value. The high-pressure compressionwear presented decreased absolute power of ${\alpha}$-wave value. It showed higher stress value. These results implicate that EEG can appropriatly indicate the change of physical comfortness of compressionwear. The appropriate tightness of compressionwear can be measured with EEG analysis rather than survey questionnaire.

• The Journal of the Society of Korean Medicine Diagnostics
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• v.15 no.1
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• pp.95-110
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• 2011

Objectives: The aim of the present study is to define breath-holding in spontaneous respiration and to observe the difference of respiratory variables, EEG and HRV. Methods: 46 healthy young volunteers (M:F=31:15) were recruited in the study. By measuring and analysing respiration, EEG and HRV in the spontaneous respiration. We segment subjects by 100% of coefficient of variation in the breath-holding. Results & Conclusions: 1. There is a period of breath-holding after expiration and before endeavored inspiration, in the course of respiration. The greater coefficient of variation in the breath-holding, longer respiration period mean, inspiration period mean and breath-holding mean in respiratory variable. 2. There was no significant difference between HRV parameters. 3. The greater coefficient of variation in the breath-holding, the higher ${\beta}$ frequency and ${\gamma}$ frequency in the left prefrontal lobe.