• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.14 no.3
• /
• pp.1026-1042
• /
• 2020

People are increasingly demanding to experience realistic behavior of virtual characters in computer games. In this article, we build a computer model for simulating a bicycle rider's behavior in a virtual riding system. A method to calculate the speed of a bicycle rider is proposed to improve the reality in a virtual riding system. In this method, the property of physical energy is introduced, and the bicycle-riding speed is calculated in real time according to the relationship between the rider's physical energy and bicycle-riding speed. Then based on the analysis of the behavior of a cyclist in a real competition, various behaviors of the virtual rider are designed and a behavior-tree for the virtual bicycle rider is constructed accordingly. On the basis of these, a virtual riding system is developed. The experiments results show that our system can simulate the behavior of a virtual bicycle rider, and thus encourage exercise on a stationary bicycle.

• Journal of Power Electronics
• /
• v.18 no.6
• /
• pp.1901-1911
• /
• 2018

This study presents a circuit model for simulating the switching transients of insulated-gate bipolar transistors (IGBTs) with inductive load switching. The modeling approach used in this study considers the behavior of IGBTs and freewheeling diodes during the transient process and ignores the complex semiconductor physics-based relationships and parameters. The proposed circuit model can accurately simulate the switching behavior due to the detailed consideration of device-circuit interactions and the nonlinear nature of model parameters, such as internal capacitances. The developed model is incorporated in an IGBT loss calculation module of an electromagnetic transient simulation program to enable the estimation of switching losses in voltage source converters embedded in large power systems.

• The Mathematical Education
• /
• v.24 no.2
• /
• pp.35-47
• /
• 1986

As computer is diffused in society widely, it is desired that we investigate on computer uses in school education. In this paper, Possibility of Micro computer uses in mathematics education is investigated. Educational computing is classified roughly three categories they are CAI CMI and Computer iteracy education. CAI is discussed at this place. Firstly, programs of mathematics educational computing is introduced and they are classified into Practicing, Tutoring, Simulating, Gaming, Demonstration, Informing. Next, the problems that we must notice in mathematics educational computing are indicated. They are computer language, development of soft ware, effectiveness of CAI etc...

• Proceedings of the Korean Radioactive Waste Society Conference
• /
• 2005.11a
• /
• pp.293-294
• /
• 2005

• 전기의세계
• /
• v.11
• /
• pp.37-43
• /
• 1963

제어계에서 사용되는 D.C. amplifier는 그 이용의 범위가 많으나 실제로 computer에 적용시킨것은 1947년에 Ragazzini에 의하여 연산증폭기(Operational amplifier)를 완성하므로서 비로서 시작한 것이다. 고로 역사가 짧은 이에 대한 연구와 사용문제는 아직까지도 계속하고 있는 것이다. 따라서 본고에서는 연산증폭기회로에 대한 조립을 구체적으로 설명하고 그의 특성을 실험으로서 얻어 TRIGA MARK-II 원자로의 simulating에 사용시킬수 있게 그 이용가치를 취급하고저 한것이다.

• Journal of the Korea Computer Graphics Society
• /
• v.10 no.3
• /
• pp.52-60
• /
• 2004

This paper presents a physically based technique for simulating complex multiphase fluids. This work is motivated by the "stable fluids" method developed by Stam to handle gaseous fluids. We extend this technique to water, which calls for the development of methods for modeling multiphase fluids and suppressing dissipation. We construct a multiphase fluid formulation by combining the Navier-Stokes equations with the level set method. By adopting constrained interpolation profile (CIP)-based advection, we reduce the numerical dissipation and diffusion significantly. We further reduce the dissipation by converting potentially dissipative cells into droplets or bubbles that undergo Lagrangian motion. Due to the multiphase formulation, the proposed method properly simulates the interaction of water with surrounding air, instead of simulating water in a void space. Moreover. the introduction of the non-dissipative technique means that, in contrast 10 previous methods, the simulated water does not unnecessarily lose mass and its motion is not damped to an unphysical extent. Experiments showed that the proposed method is stable and runs fast. It is demonstrated that two-dimensional simulation runs in real-time.

• Journal of the Korea Computer Graphics Society
• /
• v.10 no.4
• /
• pp.13-21
• /
• 2004

This paper presents a physically based technique for simulating complex multiphase fluids. This work is motivated by the "stable fluids" method developed by Stam to handle gaseous fluids. We extend this technique to water, which calls for the development of methods for modeling multiphase fluids and suppressing dissipation. We construct a multiphase fluid formulation by combining the Navier-Stokes equations with the level set method. By adopting constrained interpolation profile (CIP)-based advection, we reduce the numerical dissipation and diffusion significantly. We further reduce the dissipation by converting potential1y dissipative cel1s into droplets or bubbles that undergo Lagrangian motion. Due to the multiphase formulation, the proposed method properly simulates the interaction of water with surrounding air, instead of simulating water in a void space. Moreover, the introduction of the non-dissipative technique means that, in contrast to previous methods, the simulated water does not unnecessarily lose mass and its motion is not damped to an unphysical extent. Experiments showed that the proposed method is stable and runs fast. It is demonstrated that two-dimensional simulation runs in real-time.

• Journal of information and communication convergence engineering
• /
• v.20 no.4
• /
• pp.303-308
• /
• 2022

Simulating the heat transfer in a composite material is an important topic in material science. Difficulties arise from the fact that adjacent materials cannot match perfectly, resulting in discontinuity in the temperature variables. Although there have been several numerical methods for solving the heat-transfer problem in imperfect contact conditions, the methods known so far are complicated to implement, and the computational times are non-negligible. In this study, we developed a ResNet-type deep neural network for simulating a heat transfer model in a composite material. To train the neural network, we generated datasets by numerically solving the heat-transfer equations with Kapitza thermal resistance conditions. Because datasets involve various configurations of composite materials, our neural networks are robust to the shapes of material-material interfaces. Our algorithm can predict the thermal behavior in real time once the networks are trained. The performance of the proposed neural networks is documented, where the root mean square error (RMSE) and mean absolute error (MAE) are below 2.47E-6, and 7.00E-4, respectively.

• Journal of the Optical Society of Korea
• /
• v.12 no.4
• /
• pp.346-350
• /
• 2008

In this paper, we analyze the performance of a reliable, scalable, and cost-effective switchless wavelength division multiplexing (WDM) network based on an arrayed waveguide grating (AWG). The network efficiency is significantly increased by spatially reusing wavelengths and exploiting multiple free spectral ranges (FSRs) of the AWG employed in the architecture. We have analyzed the performance of this architecture by simulating in $Optsim^{TM}$ with a control channel which exploits the broadband light source, i.e., an LED. The data was successfully transmitted to a distance of 30 km without using any EDFA's in the network, with a reasonable BER of $4.0530{\times}10^{-14}$. We have analyzed the performance of this architecture with a control channel which exploits the broadband light source, i.e., an LED, by simulating in $Optsim^{TM}$.

• Journal of The Korean Association of Information Education
• /
• v.13 no.2
• /
• pp.205-214
• /
• 2009

The vocal language which is a symbolic vocal language described external sounds or expressed shape of things in nature, phenomenon, movement, shape of state provided images which can be envisioned in minds and created the mood for the whole writings. As the instructive ways of symbolic vocal language, the activities which refrain one-way translation for lexicon definition and stimulate the thoughts of students and interesting activities such as songs and comic books which students can understand by themselves are needed. Therefore, in this study, these symbolic vocal language is to be developed as the contents of robot for Symbolic Vocal language learning activities and after study activities, the possibility of using robot for education is to be reviewed, comparing changes in definitive areas and achievement after study activities. After the Symbolic Vocal language learning activities using robot and computer, as results of testing three achievement types of words simulated sound, shape, and movement, in study on words simulating sound and shape there was no significant difference. But The study activities simulating words used robot showed significant difference in terms of interest, confidence, and understanding.