• 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.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.10 no.6
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• pp.721-731
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• 1998

Recently, many researchers are studying the relation between thermal environment and human comfort. The purpose of this study was to obtain basic data which are necessary to determine the thermal comfort sensation and physiological responses for men in winter indoor environment. From January to February 1998, subject experiment was 40 times proceeded under twenty different conditions of air temperature and relative humidity with early-twenty male university students. We examined subjective evaluation, Electrocardiogram(ECG), Electroencephalogram(EEG) of subjects. The results of this study can be summarized as follows : The comfort zone of people in winter was achieved at Standard new effective temperature($SET^*$) $ 25.2^{\circ}C$, PMV range was obtained by Fanger's statistical calculation was －0.27＜PMV＜＋0.62, TSV range obtained subjects vote was －0.76＜TSV＜＋0.36. The largest difference of skin temperature was found at the calf area as air temperature changes. vote rate of human body presented calflongrightarrowheadlongrightarrowforearmlongrightarrowchestlongrightarrowabdo men in turn. Heart rate was decreased at low $SET^*$ and heart rate was increased at high $SET^*$ But there was no change at EEG.

• Journal of the Korean Society of Clothing and Textiles
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• v.29 no.9_10 s.146
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• pp.1230-1240
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• 2005

The purpose of this study was to apply a scientific and systematic method for assessing fashion goods' TV ads effects by EEG and questionnaires as determined by the type of ads appeal. Ads stimulants used in the survey were limited to underwear and sportswear that were advertised during $2000{\sim}2002$ on TV: 4 information-transferring and 4 emotion-evoking ads were used. Subjects were thirty healthy male and female college students. EEG was extracted from six lobes and the recorded EEG was analyzed by the range of frequency of ${\theta},\;{\alpha}\;and\;{\beta}$ waves. Data were analyzed by SPSS 11.0 with reliability test, $x^2$-analysis, t-test and frequency analysis. The emotion-evoking ads showed higher scores in memory, recall and attitude towards the ads. The responses of ${\theta}\;and\;{\alpha}$ wave were active throughout the ads but the response of ${\beta}$ wave was not. The results by the survey and the EEG test showed high similarities, indicating the EEG tests could be used as the supplementary tool for measuring ads effects.

• Journal of the Korean Institute of Telematics and Electronics
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• v.17 no.6
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• pp.28-32
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• 1980

A digital system has been designed for the detection of abnormal spikes appearing in the epileptic patient's electroencephalogram(EEG). The detection is based on the waveform characteristics of spikes, such as the large slope, the sharpness of the apex, and the time duration of the spike. After the patient's data are collected and processed suing a minicomputer and A/D converter, the computer algorithms recognize the spikes based on the parameters representing the above waveform characteristics.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.15 no.10
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• pp.2265-2271
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• 2011

This paper presents an u-health Care system based on context-awareness information. Extended project induced an education for creative engineering design. It could occur one of the issue for life care or wellness in recently life. Especially u-health Care system help on achieving this object as an efficient care-training with user blood pressure or with echocardiogram, electromyogram, electroencephalogram, or Electrocardiography. In this paper, development project show an u-health care system based on this parameters of the context-awareness with network service and analysis provide with working memory(DB) for user data base applications.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.29 no.3
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• pp.134-141
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• 2017

The purpose of this study was to analyze physiological changes via a cold air reaction experiment to generate basic data that are useful for the development of an automobile active air conditioning system to prevent drowsiness. The $CO_2$ concentration causing drowsiness in vehicle operation was kept below a certain level. Air was blown to the driver's face by using an indoor air cooling apparatus. Sleepiness and the arousal state of the driver in cold wind were measured by physiological signals. It was evident in the EEG that alpha waves decreased and beta waves increased, caused by cold air stimulation. The ${\alpha}/{\beta}$ ratio was reduced by about 52.9% and an alert state confirmed. In the electrocardiogram analysis, the efficiency of cold air stimulation was confirmed by the mean heart rate interval change. The R-R interval had a delay time of about one minute compared to the EEG response. The findings confirmed an arousal effect from sleepiness due to cold air stimulation.

• Journal of the Ergonomics Society of Korea
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• v.19 no.3
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• pp.13-21
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• 2000

Men perceive and react around him through the five senses. Also men give rise to the human sensibility and maintain his emotion. This study doesn't limit working environment to VDT environment, but considers the universal working environment acquiring information by eyesight stimulation. In case of forming an abnormal veiling reflection we consider the form ; a vertical(25%, 50%, 75%)and a horizontal(25%, 50%, 75%). The results from the subjective evaluation are analyzed by SD(Semantic Differentical methodology)of 5 point scale for visibility and nuisance when an abnormal veiling reflection forms on target. In addition, the results of the objective evaluation are suggested by measuring and analyzing EEG of bio-signal for visual sensitivity. The results of this study can apply to basic data which create a guideline of a visual operation. In particular, it can be designed as an illumination environment concerning an ergonomic factor on visual operations, mental stress such as a visual inspection operation, visual information search operation, etc. As a result, we can expect to reduce the visual nuisance and contribute to the improvement of the performance and the uplift of the competitive power.

• Journal of the Korean Society of Safety
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• v.26 no.3
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• pp.83-90
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• 2011

It is well known that urgency resulted from time stress can be a great cause to industrial accidents. Therefore, time stress has been studied in the aspect of macroscopic view, namely industrial safety management, but has not been studied in microscopic view such as psychophysiological approach. Among diverse psychophysiological indices, Electroencephalogram(EEG) would be on of 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 a simple arithmetic addition task by utilizing the power spectrum technique of EEG data. Each experiment was composed of 2 tasks under different condition - with and without time stress. As subjects, 5 young undergraduate students in their early twenties participated in this study. The results advocated a well-known fact that time stress downgrades the performance of human workers. However, correct answer rate and response time were not significantly influenced by time stress factor which might be explained by the constructural factor adopted in the present study. As in the previous studies, among various EEG-related measures, relative band power ratios of ${\alpha}$ and ${\beta}$ waves to sum of ${\alpha}$,${\beta}$,${\theta}$ wave powers, namely $P_{{\alpha}/({\alpha}+{\beta}+{\theta})}$ and $P_{{\beta}/({\alpha}+{\beta}+{\theta})}$ seemed to be the most effective measures to grasp variation of brain activities in time-stressed situation so that discussions were expanded about their variations.

• Journal of Biomedical Engineering Research
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• v.24 no.6 s.81
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• pp.487-494
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• 2003

The sleep stages provides the most basic evidence for diagnosing a variety of sleep diseases. for staging sleep by analysis of EEG(electroencephalogram), it is especially important to detect the characteristic waveforms from EEG. In this paper, sleep EEG signals were analyzed using Fourier transform and continuous wavelet transform as well as discrete wavelet transform. Proposeed system methods. Fourier and wavelet for detecting of important characteristic waves(hump, sleep spindles. K-complex, hill wave, ripple wave) in sleep EEG. Sleep EEG data were analysed using Daubechies wavelet transform method and FFT method. As a result of simulation, we suggest that our neural network system attain high performance in classification of characteristic waves.

• Journal of the Korean Society of Clothing and Textiles
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• v.44 no.5
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• pp.824-836
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• 2020

This study investigated the effects of textile attachments on electroencephalogram using 20 persons (10 males and 10 females). Four types of attachment cushions were manufactured by changing the shell fabric (cotton and microfiber) and interlining (synthetic loose fiber and buckwheat). This was done using BIOS-S8 (BioBrain Inc., Korea), an 8-channel polygraph for multi-body signal measurement, to measure EEG. Data were analyzed using the SPSS 24.0 statistical program. EEG values were significantly activated according to gender, particularly when the subjects' eyes were open. For the male cases, 'RT', 'RAHB' values were highly activated and for the female cases, 'RA', 'RB', 'RG', 'RFA', 'RST', 'RLB', 'RMB', 'RST', 'RMT' values were highly activated. Examining the differences in EEG according to type of attachment indicated no significant difference in both sexes. However, in cases of females with their eyes closed, the 'RSA' index was quite different in the left occipital lobe (O1), and when their eyes were open, the 'RFA' in the right frontal lobe (F4) showed a significant difference. However, there was no obvious correlation between the activation of EEG and the subjective preference of textile attachments.