• Journal of Korean Neurosurgical Society
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• v.64 no.2
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• pp.282-288
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• 2021

Objective : Electrooculography (EOG) records eyeball movements as changes in the potential difference between the negatively charged retina and the positively charged cornea. We aimed to investigate whether reliable EOG waveforms can be evoked by electrical stimulation of the oculomotor and abducens nerves during skull base surgery. Methods : We retrospectively reviewed the records of 18 patients who had undergone a skull base tumor surgery using EOG (11 craniotomies and seven endonasal endoscopic surgeries). Stimulation was performed at 5 Hz with a stimulus duration of 200 μs and an intensity of 0.1-5 mA using a concentric bipolar probe. Recording electrodes were placed on the upper (active) and lower (reference) eyelids, and on the outer corners of both eyes; the active electrode was placed on the contralateral side. Results : Reproducibly triggered EOG waveforms were observed in all cases. Electrical stimulation of cranial nerves (CNs) III and VI elicited positive waveforms and negative waveforms, respectively, in the horizontal recording. The median latencies were 3.1 and 0.5 ms for craniotomies and endonasal endoscopic surgeries, respectively (p=0.007). Additionally, the median amplitudes were 33.7 and 46.4 μV for craniotomies and endonasal endoscopic surgeries, respectively (p=0.40). Conclusion : This study showed reliably triggered EOG waveforms with stimulation of CNs III and VI during skull base surgery. The latency was different according to the point of stimulation and thus predictable. As EOG is noninvasive and relatively easy to perform, it can be used to identify the ocular motor nerves during surgeries as an alternative of electromyography.

• Journal of rehabilitation welfare engineering & assistive technology
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• v.5 no.1
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• pp.87-93
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• 2011

This paper proposes a method for extraction of the gaze point on display using EOG(Electrooculography) signal. Based on the linear property of EOG signal, the proposed method corrects scaling difference, rotation difference and origin difference between coordinate of using EOG signal and coordinate on display, without adjustment using the head movement. The performance of the proposed method was evaluated by measuring the difference between extracted gaze point and displayed circle point on the monitor with 1680*1050 resolution. Experimental results show that the average distance errors at the gaze points are 3%(56pixel) on x-axis, 4%(47pixel) on y-axis, respectively. This method can be used to human computer interface of pointing device for general paralysis patients or HCI for VR game application.

• Journal of Korea Multimedia Society
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• v.24 no.2
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• pp.274-284
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• 2021

Customized services to a sleep induction for better sleepcare are more effective because of different satisfaction levels to users. The EOG data measured at the frontal lobe when a person blinks his eyes can be used as biometric data because it has different values for each person. The accuracy of measurement is degraded by a noise source, such as toss and turn. Therefore, it is necessary to analyze the noisy data and remove them from normal EOG by filtering. There are low-pass filtering and high-pass filtering as filtering using a frequency band. However, since filtering within a frequency band range is also required for more effective performance, we propose a machine learning model for the filtering of EOG data in this paper as the second filtering method. In addition, optimal values of parameters such as the depth of the hidden layer, the number of nodes of the hidden layer, the activation function, and the dropout were found through experiments, to improve the performance of the machine learning filtering model, and the filtering performance of 95.7% was obtained. Eventually, it is expected that it can be used for effective user identification services by using filtering model for EOG data.

• Proceedings of the KIEE Conference
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• 1989.07a
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• pp.153-157
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• 1989

In this paper, a new method of Eye Movement Pattern Encoding (EMPE) which is based on electrooculography(EOG) was suggested for the purpose of effective communication between man and machine, instead of Point-Of-Regard-Selection (PORS) method. Also, ocular interface is designed and the typing aid, eye-pattern writer, was constructed for the test of theoretical validity and its practical aspect. Effect of eye fatigue on the performance of ocular interface was quantified through fatigue test.

• The Transactions of the Korean Institute of Power Electronics
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• v.7 no.6
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• pp.546-553
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• 2002

A control of the body posture and movement is maintained by the vestibular system, vision, and proprioceptors. Especially, vestibular system has a very important function that controls the eye movement through vestibuloocular reflex and contraction of skeletal muscles through vestibulospinal reflex. However, postural disturbance caused by loss of vestibular function results in nausea, vomiting, vertigo and loss of craving for life. Lose of vestibular function leads to abnormal reflex of eye movements named nystagmus. Analysis of the nystagmus is needed to diagnose the vertigo, which is performed by means of electrooculography(EOG). The purpose of this study is to develop a computerized system for data processing and an algorithm for the automatic evaluation of the slow component velocity(SCV) of nystagmus induced by optokinetic(OKN) stimulation system. A new algorithm using recursive least square method(RLSM) to detect SCV of nystagmus is suggested in this paper. This method allows a fast and precise evaluation of the nystagmus, through artifact rejection techniques. The results are depicted in this paper.

• The Journal of Korean Physical Therapy
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• v.25 no.5
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• pp.288-296
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• 2013

Purpose: This study was conducted in order to determine whether mechanical horseback-riding training depending on velocity can improve vestibular function and static postural balance on standing in healthy adults. Methods: For evaluation of vestibular function, electrooculography (EOG) of vertical and horizontal was performed for identification of the motion of eyes. For evaluation of static postural balance, COP distance, time spent on the sharpened Romberg test with neck extension (SRNE) were measured. Measurements were performed three times before training, three weeks after training, and six weeks after training. Participants were randomly assigned to three groups: fast velocity-mechanical horse -riding training (FV-MHRT, n=12), moderate velocity-mechanical horse-riding training (MV-MHRT, n=12), and slow velocity-mechanical horse-riding training (SV-MHRT, n=12). Results: According to the result for vertical, horizontal EOG, there was significant interaction in each group in accordance with the experiment time (p<0.05). The FV-MHRT group showed a significant decrease compared with the MV- MHRT, SV-MHRT groups (p<0.05). According to the result for static postural balance, the time spent, COP distance in SRNE showed significant interaction in each group in accordance with the experiment time (p<0.05). The time spent on the SRNE showed a significant increas in FV-MHRT, SV-MHRT (p<0.05). The COP distance of SRNE showed a significant increase in MV-MHRT (p<0.05). Conclusion: The MHRT velocity activated mechanism of vestibular spinal reflex (VSR), vestibular ocular reflex (VOR), also helped to strengthen vestibular function and static postural balance. In addition, it should be applied to different velocity of MHRT according to the specific purpose.

• Journal of Convergence for Information Technology
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• v.9 no.12
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• pp.8-16
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• 2019

Customized sleep care service needs to be provided differently for individuals since individual has different degree of sleep disorder. Because the brainwave data shows unique waveform characteristics for each person, this characteristic can be used to identify individuals. Personal identification provides an important role in enabling customized services. When you blink, you can obtain brain wave characteristics by measuring the area of the frontal lobe. Therefore, a real-time personal identification algorithm based on blinking EOG for customized sleep care service is proposed in this paper. For evaluation, 10 individuals were tested for personal identification accuracy. The results of the experiment confirmed that a maximum accuracy of 93% were taken. Algorithms can be developed by reflecting characteristics such as changes in the external environment in the future.