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Seoul, South Korea

The Seoul National University of Education is a government-run institution which provides training for future public elementary school teachers in South Korea. Founded in May 1946 under the name of Kyunggi Public Regular School, the university is the first national university that specializes in elementary school teacher training. The campus is located in the Seocho-gu district of Seoul, the capital of South Korea. The university offers graduate and undergraduate programs, and has an attached elementary school. Wikipedia.

Kwon J.,Seoul National University of Education | Lee Y.,Inha University
Computers and Education | Year: 2016

Serious games use strategies that are often applied in special education such as repetition, immediate feedback, and context-based teaching and learning. Serious games are known to increase performance on the target task and related self-efficacy, using a more cost effective method in a safer environment than traditional training (Michael & Chen, 2006). The main goal of our study was to investigate whether playing serious games can affect hands-on performance of persons with developmental disabilities. For the present study, 47 persons with developmental disabilities were divided into three groups including a control. The two experimental groups performed two hands-on tests in different orders: Apple packaging and hydroponics (AH, HA). For the first round of tests, the AH group played the Apple Packaging serious game while the HA group played the Hydroponics game. For the second round of hands-on tests, the AH group played the Hydroponics game, while the HA group played the Apple Packaging game. The control group did not play any games between the hand-on tests. Finally, all three groups performed a third round of hands-on tests. The results show that gameplay of the target task increased speed and accuracy of the target hands-on task performance. The main results of this study show that serious games can be used for training simple job skills in persons with developmental disabilities. Serious games can be implemented as part of an ongoing programme to reduce training time and enhance accuracy in a safe and enjoyable environment. © 2016 Elsevier Ltd. All rights reserved. Source

Bach K.,Yonsei University | Bach K.,Seoul National University of Education | Lee H.-W.,Sejong University
Journal of the Korean Astronomical Society | Year: 2014

Recent cosmological observations indicate that the reionized universe may have started at around z = 6, where a significant suppression around Lyα has been observed from the neutral intergalactic medium. The associated neutral hydrogen column density is expected to exceed 1021 cm-2, where it is very important to use the accurate scattering cross section known as the Kramers-Heisenberg formula that is obtained from the fully quantum mechanical time-dependent second order perturbation theory. We present the Kramers-Heisenberg formula and compare it with the formula introduced in a heuristic way by Peebles (1993) considering the hydrogen atom as a two-level atom, from which we find a deviation by a factor of two in the red wing region far from the line center. Adopting a representative set of cosmological parameters, we compute the Gunn-Peterson optical depths and absorption profiles. Our results are quantitatively compared with previous work by Madau & Rees (2000), who adopted the Peebles approximation in their radiative transfer problems. We find deviations up to 5 per cent in the Gunn-Peterson transmission coefficient for an accelerated expanding universe in the red off-resonance wing part with the rest wavelength Δλ ∼ 10 Å. © 2014. The Korean Astronomical Society. All rights reserved. Source

Jeong H.-G.,Ajou University | Lee K.-B.,Ajou University | Choi S.,Seoul National University of Education | Choi W.,Soongsil University
IEEE Transactions on Power Electronics | Year: 2010

The demand for three-phase pulsewidth modulation (PWM) inverters in applications such as power control or grid connecting has been on the increase in recent years. Such inverters are connected to the grid via an $L$ filter or an LCL filter to reduce the harmonics caused by the switching. An LCL filter can reduce the harmonics induced by low switching frequency and generates a satisfactory level of grid-side current using a relatively low inductance, as compared to an $L$ filter. The additional poles introduced by the LC part induces resonance in the system, leading to stability problems; this paper presents a compensation method using power theory to improve these issues, so that the performance of the designed LCL filter system can be improved. The effectiveness of the proposed algorithm is verified by simulations and experiments. © 2006 IEEE. Source

Kim S.-H.,Soongsil University | Choi W.,Soongsil University | Lee K.-B.,Ajou University | Choi S.,Seoul National University of Education
IEEE Transactions on Power Electronics | Year: 2011

In this paper, dynamic simulation of the equivalent circuit model of the supercapacitor, taking into account the parameter variations and self-discharge, is discussed. Self-discharge is modeled with equivalent impedance including a constant phase element (CPE), and the parameter variations depending on the voltage are reflected. Since it is difficult to directly simulate the ZARC element (R-CPE parallel circuit) with a circuit simulation tool such as the professional simulation program with integrated circuit emphasis (PSPICE), equivalent transformation to three R-C parallel circuits is introduced in the simulation. The accuracy of simulation with the model is then verified through a comparison with results of an experiment. The comparison shows that the model using a CPE is effective in representing the dynamic characteristics and self-discharge of supercapacitors. Accordingly, it proves that the method proposed in this study can be useful in developing systems that include supercapacitors, and can be applied in an integrated simulation of a supercapacitor and a power electronic system. © 2011 IEEE. Source

Jun W.,Seoul National University of Education
2015 IEEE 2nd International Conference on InformationScience and Security, ICISS 2015 | Year: 2015

The purpose of this study is to investigate correlation of internet addiction and school age. For this purpose, extensive and national survey works of NIA(National Information Society Agency of Korea) are analyzed. Based on thorough statistical analysis, it is concluded that there is a meaningful correlation between internet addiction and school age. © 2015 IEEE. Source

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