• Journal of Digital Contents Society
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• v.17 no.5
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• pp.367-373
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• 2016

In this paper, we propose a novel method to improve the accuracy of eye trackers and how to analyze them. The proposed method extracts a user profile information created by extracting gaze coordinates and color information based on the exact pupil information, and then, it maintains a high accuracy in the display. In case that extract the user profile information, the changes of the accuracy for the gaze time also is estimated and the optimum parameter value is extracted. In the experimental results for the accuracy of the gaze detection, the accuracy was low if a user took a short time in a specific point. On the other hand, when taking more than two seconds, the accuracy was measured more than 80 %.

• Journal of the Korea Convergence Society
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• v.10 no.3
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• pp.39-47
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• 2019

In this paper, we proposed extracting modified Histogram of Oriented Gradients (HOG) features using background removal when tracking pedestrians in real time. HOG feature extraction has a problem of slow processing speed due to large computation amount. Background removal has been studied to improve computation reductions and tracking rate. Area removal was carried out using S and V channels in HSV color space to reduce feature extraction in unnecessary areas. The average S and V channels of the video were removed and the input video was totally dark, so that the object tracking may fail. Histogram equalization was performed to prevent this case. HOG features extracted from the removed region are reduced, and processing speed and tracking rates were improved by extracting clear HOG features. In this experiment, we experimented with videos with a large number of pedestrians or one pedestrian, complicated videos with backgrounds, and videos with severe tremors. Compared with the existing HOG-SVM method, the proposed method improved the processing speed by 41.84% and the error rate was reduced by 52.29%.

• 한국HCI학회:학술대회논문집
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• 2009.02a
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• pp.146-149
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• 2009

Face detection and recognition in real-time video constitutes one of the recent topics in the field of computer vision. In this paper, we propose face detection and tracking algorithm using the skin color and haar-like feature in real-time video sequence. The proposed algorithm further includes color space to enhance the result using haar-like feature and skin color. Experiment results reveal the real-time video processing speed and improvement in the rate of tracking.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.8 no.5
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• pp.1080-1088
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• 2004

In this paper, the interesting moving objects tracking algorithm using color information on Multi-Video camera against variance of intensity, shape and background is proposed. Moving objects are detected by using difference image method and integral projection method to background image and objects image only with hue area, after converting RGB color coordination of image which is input from multi-video camera into HSI color coordination. Hue information of the detected moving area are segmented to 24 levels from $0^{\circ}$ to $360^{\circ}$. It is used to the feature parameter of the moving objects that are three segmented hue levels with the highest distribution and difference among three segmented hue levels. To examine propriety of the proposed method, human images with variance of intensity and shape and human images with variance of intensity, shape and background are targeted for moving objects. As surveillance results of the interesting human, hue distribution level variation of the detected interesting human at each camera is under 2 level, and it is confirmed that the interesting human is tracked and surveilled by using feature parameters at cameras, automatically.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.34 no.7
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• pp.63-70
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• 2006

This paper describes research of using area of artificial mark on vision based head tracker system. A head tracker system consists of the translational and rotational motions which are detected by web camera. Results of the motion are taken from image processing and neural network. Because of the characteristics of cockpit, the specific color on the helmet is tracked for translational motion. And rotational motion is tracked via neural network. Ratio of two different colored area on the helmet is used as input of network. Neural network algorithms used, such as back-propagation and RBFN (Radial Basis Function Network). Both back-propagation using a characteristic of feedback and RBFN using a characteristic of statistics have a good performances for the tracking of nonlinear system such as a head motion. Finally, this paper analyzes and compares with tracking performance.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.18 no.11
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• pp.2733-2737
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• 2014

Motion detection according to the movement and the change area detection method according to the background difference and the motion history image for use in a motion estimation technique using a real-time image, the motion detection method according to the optical flow, the back-projection of the histogram of the object to track for motion tracking At the heart of MeanShift center point of the object and the object to track, while used, the size, and the like due to the motion tracking algorithm CamShift, Kalman filter to track with direction. In this paper, we implemented the motion detection algorithm based on color and shape information of the object and verify.

• Journal of Yeungnam Medical Science
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• v.17 no.1
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• pp.66-74
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• 2000

Background: During the follow up period after transarterial embolization(TAE), cases of pulmonary metastasis were more prevalent in TAE-treated patients than in TAE-untreated patients. Therefore, a study was conducted to evaluate whether TAE increases the incidence of pulmonary metastasis of hepatocellular carcinoma and to clarify the risk factors for pulmonary metastasis. Methods: From March 1991 to March 1995, 156 patients who had been diagnosed with hepatocellular carcinoma by serology, and radiographic and histologic methods at Yeungnam University hospital were involved in this study. We excluded 12 patients with lung metastasis on initial diagnosis and the others. The remaining 144 patients had been followed up for at least 5 months and, divided into four groups according to lung metastasis and trans-arterial embolization treatment, and evaluated for age, sex, child-pugh score, liver cirrhosis, and level of AFP. Results: Pulmonary metastasis was found in 18.0% (26/144), of which 92.3%(24/26) and 7.7%(2/26) of the patients with and without transarterial chemoembolization, respectively. Of the patients, 23.5% (24/102) with TAE had lung metastais during follow-up periods and 4.7% (2/42) without TAE had lung metastasis. There was more likelihood for lung metastasis after TAE. but there was no difference between two groups in age, sex, child-pugh class, the presence of liver cirrhosis, and AFP. Conclusions: The incidence of pulmonary metastasis of hepatocellular carcinoma after TAE was higher. Child-pugh class was the only related clinical preciptating factors for pulmonary metastasis in TAE in our study. Our results suggest that regular chest X-ray check-ups may be more frequently needed by patients who had TAE treatment for hepatocellular carcinoma.

• Journal of Broadcast Engineering
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• v.21 no.6
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• pp.861-877
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• 2016

This paper first discusses the disadvantages of the existing CamShift Algorithm for real time face tracking, and then proposes a new Camshift Algorithm that performs better than the existing algorithm. The existing CamShift Algorithm shows unstable tracking when tracing similar colors in the background of objects. This drawback of the existing CamShift is resolved by using Kinect’s pixel-by-pixel depth information and the Skin Detection algorithm to extract candidate skin regions based on HSV color space. Additionally, even when the tracking object is not found, or when occlusion occurs, the feature point-based matching algorithm makes it robust to occlusion. By applying the improved CamShift algorithm to face tracking, the proposed real-time face tracking algorithm can be applied to various fields. The results from the experiment prove that the proposed algorithm is superior in tracking performance to that of existing TLD tracking algorithm, and offers faster processing speed. Also, while the proposed algorithm has a slower processing speed than CamShift, it overcomes all the existing shortfalls of the existing CamShift.

• Proceedings of the Korea Information Processing Society Conference
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• 2017.04a
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• pp.995-998
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• 2017

본 논문에서는 객체 추적이 가능한 쿼드콥터의 구현에 대하여 연구하였다. 드론의 안정적인 호버링 및 영상촬영을 위하여 쿼드로터의 비행원리와 PID 제어에 대한 이론을 연구하고 보다 안전한 실험환경 구성을 위한 Solution을 제시하였다. 또한 색 정보와 광흐름(Optical Flow) 기법을 공간 주파수 영역의 영상처리 방법(Nonlinear Matched Filter)과 융합하여 객체추적 하는 방법을 연구하였다.

• Journal of Korean society of Dental Hygiene
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• v.16 no.1
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• pp.45-52
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• 2016

Objectives: The purpose of the study was to investigate the cumulative dental caries rate of pit and fissure sealant in community public health program from 2005 to 2008 follow-up. Methods: The subjects were 4,768 students of 34 elementary schools in Gimcheon. The survey included direct oral examination and cumulative retention rate of pit and fissure sealant from 2005 to 2008. Data were analyzed using PASW statistical package version 18.0 and the level of significance was set at p<0.05. Results: The cumulative retention rate of sealant was 18%, 25%, and 33% after 1 year, 2 years, and 3 years, respectively. In addition, the cumulative retention rate of lower teeth was higher than that of upper teeth. Cumulative dental caries rate increased in sealed group and no sealed group. The cumulative dental caries rate decreased owing to tooth brushing frequency in sealed group and no sealed group. Conclusions: Regular and timely tooth brushing can maintain good oral health condition after tooth sealing. The school based oral health education can prevent loss of sealant and secondary caries.