• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.07b
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• pp.1150-1153
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• 2004

Diffusion coefficients Of electrons in $SF_6$-Ar mixtures gas used by MCS- BEq algorithm has been analysed over the E/N range $30\sim300$(Td) by a two term Boltzmann equation and by a Monte Carlo Simulation using a set of electron cross sections determined by other authors, experimentally the electron swarm parameters for 0.2[%] and 0.5[%] $SF_6$-Ar mixtures were measured by time-of-flight(TOF) method, The results show that the deduced electron drift velocities, the electron ionization or attachment coefficients, longitudinal and transverse diffusion coefficients and mean energy agree reasonably well with theoretical for a rang of E/N values The results obtained from Boltzmann equation method and Monte Carlo simulation have been compared with present and previously obtained data and respective set of electron collision cross sections of the molecules.

• Proceedings of the KIEE Conference
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• 2004.07e
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• pp.41-44
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• 2004

This paper describes the electron transport characteristics in $SF_6$-He gas calculated for range of E/N values from 50${\sim}$700[Td] by the Monte Carlo simulation(MCS) and Boltzmann equation(BEq) method using a set of electron collision cross sections determined by the authors and the values of electron swarm parameters are obtained by TOF method. The results gained that the values of the electron swarm parameters such as the electron drift velocity. the electron ionization or attachment coefficients. longitudinal and transverse diffusion coefficients agree with the experimental and theoretical for a range of E/N.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.13 no.4
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• pp.359-364
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• 2000

The paper describes the electron transport characteristics in SP$_{6}$+He gas calculated E/N values 0.1~700[Td] by the Monte Carlos simulation and Boltzmann equation method using a set of electron collision cross sections determined by the authors and the values of electron swarm parameters obtained by TOF method. This study gained the values of the electron swarm parameters such as the electron drift velocity the electron ionization or attachment coefficients longitudinal and transverse diffusion coefficients for SF$_{6}$+He gas at a range of E/N.E/N.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1999.05a
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• pp.696-699
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• 1999

The electron transport coefficients in $SF_6+N_2$ gas is analysed in range of E/N values from 100~900(Td) by a Monte Carlo simulation and Boltzmann method, using a set of electron collision cross sections determined by the authors. The result of the Monte Carlo simulation such as electron drift velocity, ionization and electron attachment coefficients, longitudinal and transverse diffusion coefficients in nearly agreement with the respective experimental and theoretical for a range of E/N.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.11a
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• pp.65-68
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• 2004

In the seismical capacity evaluation for RC structure wall-slab joint is very important factor. Because lateral load is resistance element and gravity load resistance element are acted mutually in the wall-slab joint. In this paper, to improve the seismic capacity of the wall-slab joint in the existing wall type apartments experiment which improve and retrofit a seismic capacity by unequal angle bracing and carbon sheet attachment are carried out. These methods are also economic and simple in mitigating seismic hazard, improve earthquake-resistance performance, and reduce risk level of building occupants. From the experimental results, the change of strength, degration of stiffness, and energy dissipation are evaluated. It can be concluded that these methods are effective in improving the seismic performance.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1999.11a
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• pp.165-168
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• 1999

The electron transport coefficients in mixture gas includes SF/sub 6/ is analysed in range of E/N values from 60∼800(Td) by the Boltzmann method that using a set of electron collision crass sections determined by the researchers. Swarm parameters in the Boltzmann method simulation such as electron drift velocity, ionization and electron attachment coefficients is in nearly agreement with the respective experimental and theoretical for a range of E/N.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.06a
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• pp.451-452
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• 2007

Drift velocities for electrons in $SF_6$-Ar mixtures gas by simulation has been analysed over the EIN range 30~300[Td] by a two term Boltzmann equation and by a Monte Carlo Simulation using a set of electron cross sections determined by other authors, experimentally the electron swarm parameters for 0.2[%] and 0.5[%] $SF_6$-Ar mixtures were measured by time-of-flight (TOF) method. The results show that the deduced electron drift velocities, the electron ionization or attachment coefficients. longitudinal and transverse diffusion coefficients and mean energy agree reasonably well with theoretical for a rang of E/N values.

• Proceedings of the Korean Vacuum Society Conference
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• 2000.02a
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• pp.187-187
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• 2000

Properties of electrical discharge in flames are investigated by making use of the ionization cross section of air. Fames have three distictive features. They are hot, emit light and are weakly ionized. We investigate influence of these three characteristics of flames on the electrical breakdown. It is found that the breakdown electric field in flames is inversely proportional to the flame temperature, thereby easily generating plasmas in flames. A swarm of low-energy electrons in flames would allow significant population of electronically excited states of flame molecules to be formed. Therefore, the analysis shows that the electronic excitation of flame molecules may also considerably reduce the breakdown field. Plasma electrons generate atomic oxygens by the electron attachment of oxygen molecules in high-pressure flames. These oxygen atoms are the most reactive radicals in flames for material oxidation. How are you and your family in this new year\ulcorner Professor Choi! I plan to go back Korea on February 6. All my family members are fine and have good time because I am here. Once I am in Korea, I will call you. I am always grateful for your helpful hand. Thank you so much.

• Journal of Advanced Information Technology and Convergence
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• v.9 no.1
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• pp.103-113
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• 2019

Motivation: Polymerized actin-based cytoskeletal structures are crucial in shape, dynamics, and resilience of a cell. For example, dynamical actin-containing ruffles are located at leading edges of cells and have a significant impact on cell motility. Other filamentous actin (F-actin) bundles, called stress fibers, are essential in cell attachment and detachment. For this reason, their mechanistic understanding provides crucial information to solve practical problems related to cell interactions with materials in tissue engineering. Detecting and counting actin-based structures in a cellular ensemble is a fundamental first step. In this research, we suggest a new method to characterize F-actin wrapping fibers from confocal fluorescence image stacks. As fluorescently labeled F-actin often envelope the fibers, we first propose to segment these fibers by diminishing an energy based on maximum flow and minimum cut algorithm. The actual actin is detected through the use of bilateral filtering followed by a thresholding step. Later, concave actin bundles are detected through a graph-based procedure that actually determines if the considered actin filament is enclosing the fiber.

• Proceedings of the KAIS Fall Conference
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• 2010.11a
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• pp.495-499
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• 2010

The biocatalytic capture of $CO_2$, and its precipitationas $CaCO_3$, over bovine carbonic anhydrase (BCA) immobilized on a pore-expanded SBA-15 support was investigated. SBA-15 was synthesized using TMB as a pore expander, and the resulting porous silica was characterized by XRD, BET, IR, and FE-SEM analysis. BCA was immobilized on SBA-15 through various approaches, including covalent attachment (BCA-CA), adsorption (BCA-ADS), and cross-linked enzyme aggregation (BCA-CLEA). The immobilization of BCA on SBA-15 was confirmed by the presence of zinc metal in the EDXS analysis. The effects of pH, temperature, storage stability, and reusability on the biocatalytic performance of BCA were characterized by examining para-nitrophenyl acetate (p-NPA) hydrolysis. The $K_{cat}/K_m$ values for p-NPA hydrolysis were 740.05, 660.62, and $680.11M^{-1}s^{-1}$, respectively, where as $K_{cat}/K_m$ for free BCA was $873.76M^{-1}s^{-1}$. The amount of $CaCO_3$ precipitate was measured quantitatively using anion-selective electrode and was found to be 12.41, 11.82, or 11.28 mg $CaCO_3$/mg for BCA-CLEA, BCA-ADS, or BCA-CA, respectively. The present results indicate that the immobilized BCA-CLEA, BCA-ADS, and BCA-CA are green materials, and are tunable, reusable, and promising biocatalysts for $CO_2$ sequestration.