• Nuclear Engineering and Technology
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• v.49 no.3
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• pp.569-575
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• 2017

One of the important requirements for the application of reduced-activation ferritic/martensitic (RAFM) steel is to retain proper mechanical properties under irradiation and high-temperature conditions. To simulate the yield strength and stress-strain curve of steels during high-temperature and irradiation conditions, a multiscale simulation method consisting of both microstructure and strengthening simulations was established. The simulation results of microstructure parameters were added to a superposition strengthening model, which consisted of constitutive models of different strengthening methods. Based on the simulation results, the strength contribution for different strengthening methods at both room temperature and high-temperature conditions was analyzed. The simulation results of the yield strength in irradiation and high-temperature conditions were mainly consistent with the experimental results. The optimal application field of this multiscale model was 9Cr series (7-9 wt.%Cr) RAFM steels in a condition characterized by 0.1-5 dpa (or 0 dpa) and a temperature range of $25-500^{\circ}C$.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1995.11a
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• pp.163-166
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• 1995

It was investigated the properties of TSC (Thermally Stimulated Current) to understand carriers behavior from long ago. Activation Energy of their properties is very important to verify electrical characteristics. So, for many years, many researchers were worked to get the activation energy, more compeletely. But, if boundary conditions were not satisfied, the values of activation energy contained several errors. In this work, to obtain the activation energy related to charged particles, the peak temperature Tp and the slope of tangential line on any coordinates of Arrhenius plot are applied. The calculation process can be denied with by computer, and the result of observation shows that the cures of calculation data and simulation data coincide very compeletely.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.02a
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• pp.302-302
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• 2010

비정질 실리콘 박막 태양전지의 설계에 있어서 빛을 처음 받아들이는 p-layer는 전체적인 태양전지 특성에 큰 영향을 준다. 본 논문에서는 window layer의 gas flow rate 변화에 따른 특성이 태양전지에 미치는 영향에 대한 simulation을 수행하였다. 가변 조건으로는 window layer의 산소와 붕소 양에 따른energy bandgap과 conductivity 그리고 activation energy를 단계별로 변화시켜 simulation을 수행하였다. Simulation 결과 산소와 붕소의 양에 따른 window layer의 특성은 태양전지의 특성에 큰 영향을 끼친다. 본 연구는 simulation data를 기반으로 real device 제작하는데 큰 도움이 될 것이다.

• Bulletin of the Korean Chemical Society
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• v.8 no.2
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• pp.111-114
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• 1987

Temperature-dependent, solution EPR spectra of two mixed-valence copper(II)-copper(I) complexes have been simulated by using modified Bloch equations. The transition probability for the intramolecular electron transfer is determined from the simulation. The transition probabilities have been fitted to the Arrhenius equation to derive the activation energies. The transition probability also varies according to the solvent used.

• The Journal of the Korea Contents Association
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• v.17 no.9
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• pp.69-76
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• 2017

This study evaluated the activation of the shielding wall and the components around the accelerator by using the medical linear accelerator. We performed simulations for energy values of 20 MV with the operating time ranging from day 1 to 30 years, and linear accelerator head and shielding wall concrete were also evaluated. The results showed that neutrons in large quantities were analyzed using high energy around thetarget point where photons were formed. Based on the activation analysis with these results, radioactivity increased with an increase in operation time and activated nuclides usually start saturating in10 years. Furthermore, the general types of nuclides formed owingto the activation were Co-60, W-181, 185, 187, Na-24, Ca-45, Mn-54, 56, and Fe-55, 59.

• Journal of Biomedical Engineering Research
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• v.15 no.4
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• pp.407-412
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• 1994

This paper describes the construction of an anisotropic three dimensional ventricular model based on the bidomain model. The cardiac activation process in the normal cardiac cell and the myocardial ischemic cell are simulated by the Huygen's principle. The depolarization process in the myocardial ischemia displays the delayed activation compared to the normal state. The repolarization process is simulated by the myocardial potential at the arbitrary ellapsed time after activation process. Using the potential data, the equivalent cardiac source at the arbitrary time can be computed. In conclusion, this simulation suggests the possibilities of the depolarization and the repolarization process in the normal and abnormal myocardiac cells.

• The Journal of the Korea institute of electronic communication sciences
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• v.5 no.2
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• pp.180-184
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• 2010

In this paper, the filter design and simulation are performed to construct the multi-channel cardiac activation main amplifier. The main amplifier consists of sample and holder, variable high pass filter, notch filter, variable low pass filter. The general 64 channel configuration is expanded into 128 channels to enhance the spatial resolution and the filter is designed for 128 channels cardiac activation main amplifier.

• Current Applied Physics
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• v.18 no.12
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• pp.1528-1533
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• 2018

The trajectories of adsorption and dissociation process of $O_2$ on the Al (111) surface were studied by the spinpolarized ab initio molecular dynamics method, and the adsorption activation energy was clarified by the NEB method with hybrid functionals. Three typical dissociation trajectories were found through simulation of $O_2$ molecule at different initial positions. When vertically approaches to the Al surface, the $O_2$ molecule tends to rotate, and the activation energy is 0.66eV. If $O_2$ molecule does not rotate, the activation energy will increase to 1.43 eV, and it makes the O atom enter the Al sublayer eventually. When the $O_2$ molecules parallel approach to the Al surface, there is no activation energy, due to the huge energy released during the adsorption process.

• Industrial Engineering and Management Systems
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• v.9 no.4
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• pp.312-322
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• 2010

An enterprise must achieve both a sound organizational management and effective development of individual members while maintaining a balanced approach. Relative to this, there is a research field dubbed as Organizational Activation. However, there is a necessity to clarify various factors required for organizational activation and to propose a methodology for organization management. This study is an attempt to create a model from an organization-a University Seminar Class-and agents therein-the Students and the Teacher-with an assumed goal of advancing together toward the students' self-growth. The model is expressed on two dimensional planes with vectors through a computer. Vectors are composed of the growth, demand, member, hindrance and student vectors. These vectors provide data to the mathematical model for a simulation. Each agent provided the individual information from the questionnaire-conducted to 169 university students. From the analysis data and extrapolations, this study was able to craft a guideline for future seminar activity. It also examines the possibility of assimilation of the Questionnaire Approach and that of the Computational Organization Theory approach. Finally, this study discusses the future possibility of application of the Assimilated Method for research and development, and for project management.

• Journal of the Korean Society of Radiology
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• v.13 no.1
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• pp.45-53
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• 2019

This study is a neutron activation for concrete that shields medical linear accelerator facilities. Comparison of general concrete and low activation concrete. The simulation method was simulated using MCNPX (Ver. 2.5.0) and FISPACT-2010, and the shielding ability for photon and neutron beams was calculated and neutron activation evaluation was carried out. As a result, the shielding capacity was 20 ~ 50 cm efficient in general concrete, and activate evaluation in low activation concrete was calculated to be low in radioactivity concrete, but all were estimated to not exceed their own allowable concentration in self - disposal. As a result of the comprehensive analysis, it is considered effective to use ordinary concrete.