• Journal of Korean Ophthalmic Optics Society
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• v.19 no.4
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• pp.533-538
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• 2014

Purpose: This study is to investigate correlation between eye fatigue and letter contrast according to letter contrast changes on monitor display. Methods: Reading speed test were carried out for 53 subjects (mean age: $22.68{\pm}1.85$ years) who have over Best-corrected visual acuity (BCVA) 1.0, and 45 subjects, who could read over 123 out of 163 letters among 53 subjects were selected. They were asked to read the letters which were composed of Black (contrast 100%), Dark gray (contrast 80%), Gray (contrast 80%), Light gray (contrast 30%) randomly. The change of their eye fatigue by letter contrast on monitor display was measured by monitoring their eyes with an eye-tracker while they were reading letters. Results: Event Duration (sec) was 33.635 for Black, 32.266 Dark gray, 33.936 for Gray, and 34.848 for Light gray. Average of Fixation Duration (sec) was 0.224 for Black, 0.218 for Dark gray, 0.239 for Gray and 0.243 for Light gray. Average of Pupil diameter (mm) was 41.133 mm for Black, 41.160 mm for Dark gray, 40.880 mm for Gray and 40.459 mm for Light gray. Frequency (blinks/sec) was 0.211 for Black, 0.206 for Dark gray, 0.221 for Gray, and 0.238 for Light gray. Conclusions: Event Duration and average of Fixation Duration were the shortest for Dark gray and the longest for Light gray. In average Pupil diameter was the biggest Dark gray and the smallest for Light gray. Blink Frequency (blinks/sec) was the lowest for Dark gray and the highest for Light gray. Visual fatigue by brightness of letters on monitor display was the least for Dark gray followed by Black, Gray and Light gray.

• Journal of Korean Ophthalmic Optics Society
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• v.19 no.2
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• pp.279-284
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• 2014

Purpose: This study will be a basic research providing data which can reduce eye strain using monitor and electric media by measuring legibility of text color on monitor. Methods: Total experimental subjects who don't have color anomaly and best corrected visual acuity was over 1.0 were 50 and their mean age was $22.83{\pm}1.47$. Reading speed test were carried out with 163 words and subjects who could read over 123 words were selected for legibility examination. Monitor background color was white and letter colors were black, blue, red, and yellow for the legibility examination. Results: In case of text color of black, blue, red, and yellow, Event duration(sec) was measured to 41.89, 42.89, 45.32, and 56.28, respevtively, and reading error (number) was measured to 1.94, 2.74, 3.36, and 5.14. Average of fixation duration(sec) was measured to 0.25, 0.26, 0.27, and 0.32. Conclusions: In this paper, event Duration, reading error and average of fixation duration which can measure the legibility was reduced in a sequence of black blue, red, and yellow.

• Journal of the Institute of Electronics and Information Engineers
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• v.49 no.9
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• pp.113-127
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• 2012

Face detection methods using image processing have been proposed in many different ways. Generally, the most widely used method for face detection is an Adaboost that is proposed by Viola and Jones. This method uses Haar-like feature for image learning, and the detection performance depends on the learned images. It is well performed to detect face images within a certain distance range, but if the image is far away from the camera, face images become so small that may not detect them with the pre-learned Haar-like feature of the face image. In this paper, we propose the far distance face detection method that combine the Aadaboost of Viola-Jones with a saliency map and user's attention information. Saliency Map is used to select the candidate face images in the input image, face images are finally detected among the candidated regions using the Adaboost with Haar-like feature learned in advance. And the user's eye-tracking information is used to select the interest regions. When a subject is so far away from the camera that it is difficult to detect the face image, we expand the small eye gaze spot region using linear interpolation method and reuse that as input image and can increase the face image detection performance. We confirmed the proposed model has better results than the conventional Adaboost in terms of face image detection performance and computational time.

• Journal of Korean Elementary Science Education
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• v.37 no.2
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• pp.206-218
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• 2018

The purpose of this study is to analyze the teaching behaviors and visual attention according to teacher's career in Elementary Science Inquire-based Class. Participants were four elementary school teachers in Seoul. They were all in grade 5 and taught science. According to the experience of elementary science education, two novice teachers and two expert teachers were identified. Participants taught Respiration in the 'Structure and Function of our Body' in the elementary science fifth grade. The mobile eye tracker used in this study is SMI's ETG 2w, which is a binocular tracking system. In addition, a video camera was installed behind the classroom to record the entire class. We recorded all the contents of the recorded video and analyzed the results. In this study, the actual practice time, participant's visual attention, and decentralized attention ability were analyzed by class phase. The results of the study are as follows. First, there was a difference between planned class time and actual practice time. The novice teachers were having difficulty in reconstructing the contents of education, and the expert teachers were reconstructing the curriculum and interacting with the students with high understanding and application of the curriculum. There were many differences between the novice teachers and the expert teachers in the tour guidance to confirm student activities. Second, if we look at the visual attention on the area related to teaching and learning by class phase, the novice teacher concentrates all the steps in a specific area, expert teachers showed an equal visual attention to meaningful areas of teaching and learning activities. Third, there was a statistically significant difference in activities 1-1, 1-2, 2-1, and 2-2 when the participants' decentralized attention ability. Expert teachers frequently checked students' understanding and interests. There was a lot of interaction with students. It is also shown through the decentralized attention ability that the novice teachers concentrate on a specific area, and the expert teachers have a high degree of decentralized attention ability and visual attention evenly.

• Reproductive and Developmental Biology
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• v.41 no.4
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• pp.65-70
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• 2017

Alpha-linolenic acid (ALA) is one of n-3 polyunsaturated fatty acids and found mainly in the chloroplasts. Many studies have been reported that intracellular reactive oxygen species (ROS) in mammalian oocytes were reduced by supplementation of ALA in in vitro maturation (IVM) medium. Based on these reports, we expected that ALA acts as an antioxidant during IVM of porcine oocytes. Therefore, the objective of this study was to investigate the antioxidant effect of ALA supplementation during IVM in porcine oocytes. The cumulus-oocyte complexes (COCs) were incubated in IVM medium containing $200{\mu}m$ $H_2O_2$ or $H_2O_2$ with $50{\mu}m$ ALA for 44 h. Nuclear maturation stage of oocytes was evaluated using aceto-orcein method. For measurement of oxidative stress state, intracellular ROS and glutathione (GSH) levels were measured using carboxy-DCFDA and cell tracker red, respectively. In results, oocytes in metaphase-II (MII) stage development was significantly reduced in $H_2O_2$ group compared to non-treated control group $61.84{\pm}1.42%$ and 80.00%, respectively; p<0.05) and it was slightly recovered by treatment of ALA ($69.76{\pm}1.67%$; p<0.05). The intracellular GSH levels was decreased in $H_2O_2$ groups compared with control groups, but it was enhanced by ALA treatment (p<0.05). On the contrary, $H_2O_2$ treatment increased intracellular ROS level in oocytes and $H_2O_2$-induced ROS was decreased by treatment of ALA (p<0.05). Our findings suggested that ALA treatment under oxidative stress condition improve oocyte maturation via elevated GSH and reduced ROS levels in oocytes. Therefore, these results suggest that ALA have an antioxidative ability and it could be used as antioxidant in in vitro production system of porcine embryo.

• Journal of Korea Multimedia Society
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• v.15 no.4
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• pp.425-438
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• 2012

In this paper, We propose Augmented Reality (AR) System for the interaction between user's hand motion and virtual object motion based on computer vision. The previous AR system provides inconvenience to user because the users have to control the marker and the sensor like a tracker. We solved the problem through hand motion and provide the convenience to the user. Also the motion of virtual object using a physical phenomenon gives a reality. The proposed system obtains geometrical information by the marker and hand. The system environments like virtual space of moving virtual ball and bricks are made by using the geometrical information and user's hand motion is obtained from the hand's information with extracted feature point through the taping hand. And it registers a virtual plane stably by getting movement of the feature points. The movement of the virtual ball basically is parabolic motion with a parabolic equation. When the collision occurs either the planes or the bricks, we show movement of the virtual ball with ball position and normal vector of plane and the ball position is faulted. So we showed corrected ball position through experiment. and we proved that this system can replaced the marker system to compare to jitter of augmented virtual object and progress speed with it.

• Reproductive and Developmental Biology
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• v.35 no.3
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• pp.287-294
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• 2011

Autophagy is a process of intracellular bulk protein degradation, in which the accumulated proteins and cytoplasmic organelles are degraded. It plays important roles in cellular homeostasis, apoptosis, and development, but its role during early embryo development remains contentious. Therefore, in the present study, we investigated the effects of 3-methyladenine (3-MA) on early embryonic development in pigs, we also investigated several indicators of developmental potential, including mitochondrial distribution, genes expressions (autophagy-, apoptosis- related genes), apoptosis and ER-stress, which are affected by 3-MA. After in vitro maturation and fertilization, presumptive pig embryos were cultured in PZM-3 medium supplemented with 3-MA for 2 days at $39^{\circ}C$ 5% $CO_2$ in air. Developmental competence to the blastocyst stage in the presence of 3-MA was gradually decreased according to increasing concentration. Thus, all further experiments were performed using 2 mM 3-MA. Blastocysts that developed in the 3-MA treated group decreased LC3-II intensity and expressions of autophagy related genes than those of the untreated control, resulting in down-regulates the autophagy. Terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) showed that the number of containing fragmented DNA at the blastocyst stage increased in the 3-MA treated group compared with control ($6.0{\pm}1.0$ vs $3.3{\pm}0.6$, p<0.05). Also, the expression of the pro-apoptotic gene Bax increased in 3-MA treated group, whereas expression of the anti-apoptotic gene Bcl-XL decreased. Mito Tracker Green FM staining showed that blastocysts derived from the 3-MA treated group had lower mitochondrial integrity than that of the untreated control, resulting in decrease the embryonic qualities of preimplantation porcine blastocysts. Then, the expression of the spliced form of pXBP-1 product (pXBP-1s) increased in 3-MA treated group, resulting increase of ER-stress. Taken together, these results indicate that inhibition of autophagy by 3-MA is closely associated with apoptosis and ER-stress during preimplantation periods of porcine embryos.

• Journal of Korean Ophthalmic Optics Society
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• v.15 no.3
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• pp.263-268
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• 2010

Purpose: Eye movements and fixation ability are an important procedure to obtain external information and essential means of clear vision. The purpose of this study was to determine the reading performance such as reading time and number of fixations when random text was viewed at varying distances. Methods: Twenty two presbyopes were participated. All subjects were screened for their suitability to participate in the study by clinical examination, and none of the participants had previously worn contact lenses and no previous experience of wearing any types of presbyopic vision correction except single vision. The reading time and number of fixations were recorded using eye tracker while each subjects was waring four vision corrections which included single vision for distance (SV), bifocal spectacle lenses (BIF), progressive addition lenses (PAL), and monovision (MV). The reading material was presented at distance and near distance. Results: Reading time and number of fixations for near stimulus were significantly different among vision correction used in this study (p<0.001). In particular, wearing SV required longer reading time and produced longer fixation duration for near text. However, reading distance text was similarity performed across vision corrections tested and there was no statistical difference found for either reading time and number of fixations. Conclusions: Wearing presbyopic vision correction is advantageous for reading task of near stimuli, but not having near correction such as wearing SV could result in longer reading time and higher number of fixation due to lacks of accommodative ability for near task. For the future studies, it would be interesting to examine the performance of reading both at adapted and unadapted stages as examining only unadapted wearers was limitation of this study.

• Journal of the Institute of Electronics and Information Engineers
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• v.51 no.5
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• pp.35-43
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• 2014

In this paper, we propose a performance enhancement method of the target tracking system for communication signal using the monopulse and the ${\alpha}{\beta}$ filter to keep the connection of the communication system between the airplane and the ground. We suggest the minimum distance measurement method for tracking error angle of the monopulse signal instead of the generally used method of MR(Monopulse Ratio) curve, and the ${\alpha}{\beta}$ filter with variable gain for enhancement of the tracking accuracy and the probability of re-tracking the monopulse signal under the disconnection of link. We show the performance enhancement of the proposed method of monopulse system using the measured MR Curve results of the prototype system. And also, the comparison of simulation results between the ${\alpha}{\beta}$ filter with variable gain and the ${\alpha}{\beta}$ filter with fixed gain shows the performance enhancement of the proposed ${\alpha}{\beta}$ filter. Using the proposed methods, we expect the enhanced performance of the existing target tracking system for communication signal only by changing the algorithm without hardware changes.

• Journal of The Korean Association For Science Education
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• v.34 no.8
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• pp.795-806
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• 2014

The purpose of this study is to develop an intervention program for improvement of elementary science-poor students' Basic Science Process Skill (BSPS) and to validate the intervention program's effectiveness using eye-tracker. The participants of this study were 35 elementary science-poor students. This study's method was the analysis of real-time eye movements during basic science process skill problem solving. SMI's 120 Hz iView XTM RED was used to collect EMD (eye movement data). Experiment 3.4 and BeGaze 3.4 programs were used to design experiment and to analyze EMD. The results of this study are as follows. First, we developed an intervention program including BSPS instructional strategy, behavior of teachers & student according instructional strategy stage, teachinglearning plan and learning note. Second, science poor students' BSPS ability has improved statistically significantly through the application of intervention program and BSPS problem-solving time decreased statistically significantly. Third, AFT (average fixation time) of BSPS Question and keyword area decreased statistically significantly. Fourth, APD (average pupil diameter) of BSPS problem-solving process expanded statistically significantly. Fifth, AST (average saccade time) of BSPS problem-solving process increased statistically significantly. Sixth, AFET (average fixation entry time) of BSPS problem-clue area was accelerated statistically significantly, AFT of BSPS problem-clue area reduced statistically significantly.