• 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.

• Korean Journal of Applied Biomechanics
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• v.25 no.2
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• pp.175-182
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• 2015

Objective : The purpose of this study was to investigate difference in fascicle behavior of the medial gastrocnemius during the locomotion with varying intensities, such as gait and one-legged and two-legged vertical jumping. Methods : Six subjects (3 males and 3 females; age: $27.2{\pm}1.6yrs.$, body mass: $62.8{\pm}9.8kg$, height: $169.6{\pm}8.5cm$) performed normal gait (G) at preferred speed and maximum vertical jumping with one (OJ) and two (TJ) legs. While subjects were performing the given tasks, the hip, knee and ankle joint motion and ground reaction force was monitored using a 8-infrared camera motion analysis system with two forceplates. Simultaneously, electromyography of the triceps surae muscles, and the fascicle length of the medial gastrocnemius were recorded using a real-time ultrasound imaging machine. Results : Comparing to gait, the kinematic and kinetic parameters of TJ and OJ were found to be significantly different. Along with those parameters, change in the medial gastrocnemius (MG) muscle-tendon complex (MTC) length ($50.57{\pm}6.20mm$ for TJ and $44.14{\pm}5.39mm$ for OJ) and changes in the fascicle length of the MG ($18.97{\pm}3.58mm$ for TJ and $20.31{\pm}4.59mm$ for OJ) were observed. Although the total excursion of the MTC and the MG fascicle length during the two types of jump were not significantly different, however the pattern of length changes were found to be different. For TJ, the fascicle length maintained isometric longer during the propulsive phase than OJ. Conclusion : One-legged and two-legged vertical jumping use different muscle-tendon interaction strategies.

• Korean Journal of Applied Biomechanics
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• v.18 no.2
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• pp.125-139
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• 2008

The purpose of this study is to compare and analyze a kinematic characteristics of throwing performance among born visually impaired, postnatal visually impaired and visually correct people through their kinematic characteristics. Another purpose of this study is to prevent injury and improve blind's exercise leadership and physical abilities. Three video cameras were used and each camera's shooting velocity was 60field/sec. Then the longest thrown pose was collected and analyzed by using Kwon 3D ver. 3.1 program. The results obtained from this study were followings; 1. During release, the fastest speed of ball was visually corrected followed by postnatal visually impaired and then born visually impaired. 2. Visually corrected used wrist joint well and had wide body round range with similar motion patterns, however born visually impaired couldn't do this at all. 3. Visually corrected used waist to lead shoulder at Phase 2 while throwing ball, but some of born visually impaired and postnatal visually impaired couldn't use waist to lead shoulder. 4. Visually corrected looked at the way where ball would go, but blinds couldn't look where ball would go. 5. Not like visually corrected who show similar patterns, born visually impaired showed each different patterns and some postnatal visually impaired showed similar patterns with visually corrected. 6. While throwing ball, visually corrected showed flexible weight-movement, postnatal visually impaired were not good as visually corrected, and born visually impaired couldn't do weight-movement at all. Synthetically, this result showed that throwing motions are affected a lot by the time when people became blind.

• The Korean Journal of Nuclear Medicine Technology
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• v.18 no.2
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• pp.28-32
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• 2014

Purpose Patient motion during myocardial perfusion SPECT can produce images that show visual artifacts and perfusion defects. This artifacts and defects remain a significant source of unsatisfactory myocardial perfusion SPECT. Motion correction has been developed as a way to correct and detect the patient motion for reducing artifacts and defects, and each motion correction uses different algorithm. We corrected simulated motion patterns with several motion correction methods and compared those images. Materials and Methods Phantom study was performed. The anthropomorphic torso phantom was made with equal counts from patient's body and simulated defect was added in myocardium phantom for to observe the change in defect. Vertical motion was intentionally generated by moving phantom downward in a returning pattern and in a non-returning pattern throughout the acquisition. In addition, Lateral motion was generated by moving phantom upward in a returning pattern and in a non-returning pattern. The simulated motion patterns were detected and corrected similarly to no-motion pattern image and QPS score, after Motion Detection and Correction Method (MDC), stasis, Hopkins method were applied. Results In phantom study, Changes of perfusion defect were shown in the anterior wall by the simulated phantom motions, and inferior wall's defect was found in some situations. The changes derived from motion were corrected by motion correction methods, but Hopkins and Stasis method showed visual artifact, and this visual artifact did not affect to perfusion score. Conclusion It was confirmed that motion correction method is possible to reduce the motion artifact and artifactual perfusion defect, through the apply on the phantom tests. Motion Detection and Correction Method (MDC) performed better than other method with polar map image and perfusion score result.

• Journal of the Korean Society for Nondestructive Testing
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• v.27 no.5
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• pp.426-431
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• 2007

When a high-energy ultrasound propagates through a solid body that contains a crack or a delamination, the two faces of the defect do not ordinarily vibrate in unison, and dissipative phenomena such as friction, rubbing and clapping between the faces will convert some of the vibrational energy to heat. By combining this heating effect with infrared imaging, one can detect a subsurface defect in material in real time. In this paper a realtime detection of the brazing defect of thin Inconel plates using the UIR (ultrasonic infrared imaging) technology is described. A low frequency (23 kHz) ultrasonic transducer was used to infuse the welded Inconel plates with a short pulse of sound for 280 ms. The ultrasonic source has a maximum power of 2 kW. The surface temperature of the area under inspection is imaged by an infrared camera that is coupled to a fast frame grabber in a computer. The hot spots, which are a small area around the bound between the two faces of the Inconel plates near the defective brazing point and heated up highly, are observed. And the weak thermal signal is observed at the defect position of brazed plate also. Using the image processing technology such as background subtraction average and image enhancement using histogram equalization, the position of defective brazing regions in the thin Inconel plates can be located certainly.

• Archives of design research
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• v.16 no.2
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• pp.323-334
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• 2003

This study is focused on subjective images that are produced before visualization in the digital information environment and on characteristics of objective, dynamic image expression that specifies the subjective images. In this study, the visual world that works in the action of "see"is expanded into vision of eyes, vision of brain, and vision of camera. Also we have redefined the definitions of image and its materialized image, yeongsang. It is defined that image contains a strong meaning of consciousness and mind, and that yeongsang involves vision in which constantly changing information of light is created and reproduced by physical processes. We made it clear that image expression in the 21 st century is becoming more generalized, simplified, and concentrated, by the digital technology, from existing specific non-real images to "informationalized" non-real images. This means that there exists an intrinsic difference in the expressional form of the modern analog environment and that of the recent digital environment in the area of yeongsang communication. Along with development of technology, image information raises plastic reality through indirect experience in the virtual space by expanding the sensual faculty of human. However, there also is a tendency for humans to rely more on technology instead of utilizing their creative faculty. Image expression by“the digital information environment” in the 21st century will pursue two sides; one is to shift from external expression of the human body in the cyber space to internal expression, and the other is to internalize the image world and make it connected worldwide. Further research is necessary in these fields.ary in these fields.

• KIPS Transactions on Computer and Communication Systems
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• v.6 no.6
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• pp.271-280
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• 2017

In this paper, we propose a new safety system composed of wearable devices, driver's seat belt, and integrating controllers. The wearable device and driver's seat belt capture driver's biological information, while the integrating controller analyzes captured signal to alarm the driver or directly control the car appropriately according to the status of the driver. Previous studies regarding driver's safety from driver's seat, steering wheel, or facial camera to capture driver's physiological signal and facial information had difficulties in gathering accurate and continuous signals because the sensors required the upright posture of the driver. Utilizing wearable sensors, however, our proposed system can obtain continuous and highly accurate signals compared to the previous researches. Our advanced wearable apparatus features a sensor that measures the heart rate, skin conductivity, and skin temperature and applies filters to eliminate the noise generated by the automobile. Moreover, the acceleration sensor and the gyro sensor in our wearable device enable the reduction of the measurement errors. Based on the collected bio-signals, the criteria for identifying the driver's condition were presented. The accredited certification body has verified that the devices has the accuracy of the level of medical care. The laboratory test and the real automobile test demonstrate that our proposed system is good for the measurement of the driver's condition.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.49 no.2
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• pp.35-44
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• 2012

Most recent infrared (IR) sensors have a focal-plane array (FPA) structure. Spatial non-uniformity of a FPA structure, however, introduces unwanted fixed pattern noise (FPN) to images. This non-uniformity correction (NUC) of a FPA can be categorized into target-based and scene-based approaches. In a target-based approach, FPN can be separated by using a uniform target such as a black body. Since the detector response randomly drifts along the time axis, however, several scene-based algorithms on the basis of a video sequence have been proposed. Among those algorithms, the state-of-the-art one based on Kalman filter uses one-directional warping for motion compensation and only compensates for offset non-uniformity of IR camera detectors. The system model using one-directional warping cannot correct the boundary region where a new scene is being introduced in the next video frame. Furthermore, offset-only correction approaches may not completely remove the FPN in images if it is considerably affected by gain non-uniformity. Therefore, for FPN reduction in IR videos, we propose a joint correction algorithm of gain and offset based on bi-directional warping. Experiment results using simulated and real IR videos show that the proposed scheme can provide better performance compared with the state-of-the art in FPN reduction.

• Korean Journal of Environment and Ecology
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• v.32 no.3
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• pp.256-260
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• 2018

Cannibalism is a widely observed phenomenon in the animal kingdom. However, it is rarely found among birds outside nests in the wild because it occurs irregularly and it is almost impossible to monitor animal behavior constantly. On 17 January 2017, this behavior was directly observed from a group of vultures feeding on a conspecific in a paddy field near Lake Geumho in Haenam-gun ($34^{\circ}35^{\prime}58.25^{{\prime}{\prime}}N$, $126^{\circ}26^{\prime}57.64^{{\prime}{\prime}}E$). It was observed and recorded with the binoculars and a camera with a telephoto lens in a car approximately 20 m (or 60 m) away from the site. The observer approached the feeding site after the last vulture had finished feeding and flown away and found remains of a vulture, including body feathers, skull, sterna keel, and both legs. It was the first report of cannibalism in Cinereous vulture Aegypius monachus in its overwintering grounds. The remaining skeleton was very fleshy, and the surrounding grass was wet with the blood of vulture. No other traces of a mammal or bird that could have been the vultures' prey were found. This report provides a detailed account of the events related to this rare observation and the causes that might have led to it.

• Journal of the Institute of Electronics and Information Engineers
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• v.51 no.11
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• pp.221-228
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• 2014

The color and shape of the tongue reflect the physiological and clinico-pathological condition of the body. Recently, various tongue image acquisition devices have been developed for accurate diagnosis based on quantitative and objective tongue features. Since a color information is essential for tongue diagnosis, the performance of an illuminator is very important for the tongue image acquisition device. In this study, we developed an indirect illumination, which is possible to improve a homogeneity of light intensities on the tongue surface, and evaluated its performances. In order to realize the indirect illumination (II), a semi-ellipsoidal solid structure (SESS) for the light reflex was located in the system, and two high-brightness white LEDs were placed for illuminating the areas under frontal camera in the SESS. The tongue surface was illuminated by reflected light from the SESS. The light homogeneity induced by three different illuminations including the II was evaluated by calculating coefficient of variation (CV) of illuminance of five regions. The II showed less than 0.01 of CV and the direct illumination (DI) and the direct illumination with a light diffusion plate (DILDP) showed 0.16 and 0.13, respectively. The reflexed pixel ratios of tongue phantom images show 5.76%, 4.22%, 1.79% for the DI, the DILDP and the II, respectively. The homogeneity of a tongue phantom was evaluated by calculating CV of mean pixel values of six different tongue regions, and showed less than 0.06 in the II. If the II technique apply to tongue diagnosis system, it is expected to improve diagnostic accuracy in clinic.