• Annals of Clinical Neurophysiology
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• v.4 no.2
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• pp.146-148
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• 2002

Progressive systemic sclerosis (PSS) is a multi-systemic disorder characterized by abundant fibrosis of the skin, blood vessels, and visceral organs. But it rarely affects the peripheral nervous system. We report a 36-year-old man of painful trigeminal neuropathy as a complication of PSS. He was referred from Rheumatology for the evaluation of abruptly developed bilateral facial pain. He had facial hypesthesia and paresthesia on neurologic examinations. In the blink reflex, ipsilateral and contralateral R1 and R2 responses were not detected during bilateral supraorbital stimulation. But normal latency and CMAP amplitude of facial NCV were found. Under the impression of trigeminal neuropathy caused by PSS, steroid therapy was tried, and his clinical symptoms and electrophysiologic findings were improved. PSS could be the cause of the painful trigeminal neuropathy.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.43 no.1
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• pp.40-48
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• 2015

In this paper, we suggest a measurement modeling of the RF seeker using the ISAR(Inverse Synthetic Aperture Radar) image. Reference scattering points are extracted first from ISAR images which are changed according to target attitude. And then uncertainties included in RF seeker measurement such as noise strength, blink, and boresight error are added to the reference scattering points. The proposed measurement model of the RF seeker can be used to develop various kinds of target tracking algorithms.

• The Journal of the Korea Contents Association
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• v.18 no.1
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• pp.1-9
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• 2018

A keyboard system for hands-free virtual reality head mounted display using electrooculogram (EOG) signal which occurs during the eye-blinking is proposed. This system consists of display device, gyroscope sensor, gravity sensor and electro-encephalogram (EEG) sensor, and it is implemented with Unity3D engine for system control and graphic processing. If the input language of proposed keyboard system is Korean, i.e. Hangul, the Chonjiin keyboard method is utilized; but for the English spelling, numbers or special characters, $3{\times}4$ keyboard method is used in order to solve the spatial problem. By the implemented method, it can be verified that the user can handle the keyboard input of virtual reality head mounted display with only neck movement and EOG, instead of using hands.

• Journal of Korea Multimedia Society
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• v.19 no.9
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• pp.1723-1737
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• 2016

When watching 3D contents, people often experience various visual discomforts like tiredness, dryness, headaches, and dizziness. Previous researches on visual discomfort analyzed and concluded vergence-accommodation conflict, viewing distance, and brightness changes to be the causes of visual discomfort. Yet it is necessary to systematically analyze the visual discomfort due to the changes in object, background brightness and viewing distance. In this paper, we produce four videos that have four different background brightness and two different viewing distances to solve analyze the visual discomfort from watching 3D contents. We measure and analyze eye-blink and saccadic movement, saccadic latency, Nearest Point of Convergence (NPC), and participant survey for amore accurate result compared to previous researches. Our results show that the eye-blink rate and saccadic latency increase when the background is bright and viewing distance is close while the saccadic movement decreases in the same environment. However, NPC only changes when the background brightness changes. We confirm that the bright background and near viewing distance create greater visual discomfort and decrease depth perception abilities.

• Journal of IKEEE
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• v.22 no.4
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• pp.1109-1114
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• 2018

Electroencephalogram (EEG) is a tool used to study brain activity caused by external stimuli. In this process, artifacts are mixed and it is easy to distort the signal, so post-processing is necessary to remove it. Independent Component Analysis (ICA) is a widely used method for removing artifact. This method has a disadvantage in that it has excellent performance but some loss of brain wave information. In this paper, we propose a method to reduce EEG information loss by restricting the filter coverage using eye blink information obtained from Eyetracker. We then compared the results of the proposed method with the conventional method using quantization methods such as Signal to Noise Ratio (SNR) and Spectral Coherence (SC).

• Korean Journal of Cognitive Science
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• v.27 no.2
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• pp.275-301
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• 2016

Attentional blink (AB) refers to the phenomena where conscious report for a target (T2) subsequent to the first target (T1) in a stream of items under rapid serial visual presentation (RSVP) becomes difficult if the T2 follows no later than 500ms after the T1. The present study examined the effect of T1 visibility on T2 AB strength according to the bottleneck account proposing that the amount of allocated resources for T1 memory consolidation determines the strength of AB against T2. In the low-visibility condition, the T1 had a gray color for a low stimulus contrast against the black background whereas had a bright and saturated color in the high-visibility condition. In both visibility conditions, the T1 was also highly distinct from the remaining distractors. A multi-RSVP method was also used for increasing location uncertainty of the targets supposedly consuming on average attentional resources for the targets. Two experiments revealed that AB strength was more intense in the low-visibility than high-visibility condition, and the pattern of difference went more pronounced if T2 visibility was improved. The results indicate that T1 visibility can affect more strongly when attentional resources are relatively lacking for resolving the T1 bottleneck, and support for the bottleneck account proposing that the level of T1's visibility can determine the intensity of the T1 bottleneck.

• Journal of Korean Ophthalmic Optics Society
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• v.13 no.1
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• pp.15-20
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• 2008

Purpose: To study on the confidence of dry eye diagnosis methods which need to prescribe contact lens. Methods: Non-invasive tear film break-up time (NIBUT) and tear film break-up time (TBUT) were measured in forty healthy subjects in their 20s, and then the subjects were classified into normal eye and dry eye. The results of McMonnies questionnaire, tear prism height measurement, Hardtack test, blink rate measurement and Schirmer test were compared with the results of NIBUT and TBUT. Results: The results of NIBUT and TBUT were as follows; 20 subjects had normal eyes, 10 subjects had dry eyes in both NIBUT and TBUT, and 10 subjects showed different results. In McMonnies questionnaire, the score of normal eye group averaged 8.2 and that of dry eye group averaged 18.5, which showed statistically significant difference. Furthermore, 100% of normal eye group classified by the results of NIBUT and TBUT corresponded with the result of McMonnies questionnaire and 90% of dry eye group showed the correspondence. Tear prism height of normal eye group averaged 0.32 mm and that of dry eye group averaged 0.23 mm, which were significantly different. Hardtack test, blink rate measurement and Schirmer test without local anesthesia showed no statistically significant difference between normal eye group and dry eye group. Conclusions: On dry eye diagnosis methods, the results of McMonnies questionnaire and tear prism height measurement had close correlation with the results of NIBUT and TBUT.

• Journal of Advanced Navigation Technology
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• v.10 no.2
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• pp.95-102
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• 2006

In this paper, we model a traffic of multiple tags operated in 2.45GHz band RTLS environment and analyze the multi-tag interference. Also, we propose a high precision location estimation algorithm of RTLS and then analyze its performance. From the results, the BER performance of RTLS degrades as the number of multi-tags increase in Gaussian noise and fading(m=15) environment. To meet the BER specification of RTLS, $10^{-5}$, we have to limit the multi-tag number to below 40. We also estimate the tag's location in $250m{\times}250m$ searching-area with enhanced TDOA scheme. It is confirmed that the 3m radius within accuracy of RTLS specification is satisfied, if the number of sub-blink receives more than 2 when available reader is 3 to 8.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.39C no.2
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• pp.122-129
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• 2014

In this study, emotion-classification gathered from users was performed, classification-experiments were then conducted using SVM(Support Vector Machine) and K-means algorithm. Total 15 numbers of channels; CP6, Cz, FC2, T7. PO4, AF3, CP1, CP2, C3, F3, FC6, C4, Oz, T8 and F8 among 32 members of the channels measured were adapted in Brain signals which indicated obvious the classification of emotions in previous researches. To extract emotion, watching DVD and IAPS(International Affective Picture System) which is a way to stimulate with photos were applied and SAM(Self-Assessment Manikin) was used in emotion-classification to users' emotional conditions. The collected users' Brain-wave signals gathered had been pre-processing using FIR filter and artifacts(eye-blink) were then deleted by ICA(independence component Analysis) using. The data pre-processing were conveyed into frequency analysis for feature extraction through FFT. At last, the experiment was conducted suing classification algorithm; Although, K-means extracted 70% of results, SVM showed better accuracy which extracted 71.85% of results. Then, the results of previous researches adapted SVM were comparatively analyzed.

• Journal of Korean Ophthalmic Optics Society
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• v.6 no.2
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• pp.161-164
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• 2001

The purpose of our study was stability of tear film for Korean. In the 1970s, the major problem for the contact lens practitioner was the management of contact lens parameters. In the 1980s, oxygen permeability was the main problem in contact lens practice: now it is dry eyes. To appropriately fit the patient with contact lenses it is imperative to know in advance if the patient has a marginal dry eye. Based on the initial diagnosis appropriate care can be taken to minimize problems with the result that the patient can successfully wear contact lenses. A well known test for dry eyes is Schirmer test which has shown to be useful for diagnosing Sjogren syndrome. Biomicroscopy can often unmask numerous problems. The classical test for marginal dry eye is measuring the tear break up time(TBUT). A dry eye problem with contact lenses is often caused by the lid. If an incomplete blink is responsible for the dry eye it is possible to change the situation by blinking exercises. The result of these test, mean value of age was 22.8, mean value of blink rate was 19 times/min, mean value of Schirmer test was 25 mm/5 min, mean value of TBUT was 7.1 sec.