• Proceedings of the KIEE Conference
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• 2001.07e
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• pp.76-79
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• 2001

Energy distribution function in $SiH_4$ has been analysed over the E/N range $0.5{\sim}300Td$ and Pressure value 0.5, 1.0, 2.5 Torr by a two-term approximation Boltzmann equation method and by a Monte Carlo simulation. The motion has been calculated to give swarm parameters for the electron drift velocity, diffusion coefficient, electron ionization, mean energy and the electron energy distribution function. The electron energy distribution function has been analysed in $SiH_4$ at E/N=30, 50Td for a case of the equilibrium region in the mean electron energy and respective set of electron collision cross sections.

• Journal of the Korean Ceramic Society
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• v.50 no.1
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• pp.31-36
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• 2013

${\beta}$-SiC powders were synthesized by a carbothermal reduction process using $SiO_2$-C precursors fabricated by a sol-gel process using phenol resin and TEOS as starting materials for carbon and Si sources, respectively. The C/Si molar ratio was selected as an important parameter for synthesizing SiC powders using a sol-gel process, and the effects of the C/Si molar ratio (1.4-3.0) on the particle size, particle size distribution, and yield of the synthesized ${\beta}$-SiC powders were investigated. It was found that (1) the particle size of the synthesized ${\beta}$-SiC powders decreased with an increase in the C/Si molar ratio in the $SiO_2$-C hybrid precursors, (2) the particle size distribution widened with an increase in the C/Si molar ratio, and (3) the yield of the ${\beta}$-SiC powder production increased with an increase in the C/Si molar ratio.

• Korean Journal of Materials Research
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• v.20 no.9
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• pp.457-462
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• 2010

Adsorption of a water molecule on a Si (001) surface and its dissociation were studied using density functional theory to study the distribution of -OH fragments on the Si surface. The Si (001) surface was composed of Si dimers, which buckle in a zigzag pattern below the order-disorder transition temperature to reduce the surface energy. When a water molecule approached the Si surface, the O atom of the water molecule favored the down-buckled Si atom, and the H atom of the water molecule favored the up-buckled Si atom. This is explained by the attractions between the negatively charged O of the water and the positively charged down-buckled Si atom and between the positively charged H of the water and the negatively charged up-buckled Si atom. Following the adsorption of the first water molecule on the surface, a second water molecule adsorbed on either the inter-dimer or intra-dimer site of the Si dimer. The dipole-dipole interaction of the two adsorbed water molecules led to the formation of the water dimer, and the dissociation of the water molecules occurred easily below the order-disorder transition temperature. Therefore, the 1/2 monolayer of -OH on the water-terminated Si (001) surface shows a regular distribution. The results shed light on the atomic layer deposition process of alternate gate dielectric materials, such as $HfO_2$.

• Journal of Distribution Science
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• v.22 no.2
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• pp.63-69
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• 2024

Purpose: This study analyses the Service Development Strategy for MICE in Nakhon Si Thammarat Province, Thailand aim to 1) Investigate the current and desirable conditions of the service businesses in order to support the MICE 2) Undertake a SWOT analysis of service businesses with regard to supporting the MICE 3) Analyze service business distribution strategies development to support the MICE in Nakhon Si Thammarat Province. Research design, data and methodology: This study divided into 2 phases: Phase 1 involved qualitative research to study the process of service businesses in their support of the MICE. Phase 2 involved research and development with regard to the development of innovative service business development strategies to support the MICE. Results: The article showed that company executives and related parties understand the meaning of service business management to support the MICE to consist of 8 indicators: quality of meeting venues, access to meeting venues, meeting infrastructure, government support, additional activities in addition to meetings, the image and reputation of the city, MICE personnel, and security. Conclusions: Strategies for developing service business innovations to support the MICE consist of a proactive strategy, a preventive strategy, and a remedial strategy together with defensive strategies.

• Journal of Korea Foundry Society
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• v.29 no.2
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• pp.78-85
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• 2009

Functionally graded microstructure of centrifugal cast Al-Si alloy, especially distribution of primary Si particles according to the changes of melt pouring temperature and rotation frequency was investigated by numerical simulation. Moving velocity of Si particles increased as the melt pouring temperature and rotational frequency of mold increased. Therefore, segregation tendency of primary Si particles toward inner side of cylindrical sample increased as the melt pouring temperature and rotational frequency of mold increased. Rich distribution region of particles was located at 0.9, 0.7, 0.4 mm from inner surface of cylindrical sample under the centrifugal cast condition of $750^{\circ}C$ melt pouring temperature and 1500, 2000 and 2500 rpm mold rotational frequencies, respectively, by numerical simulation.

• Journal of ILASS-Korea
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• v.2 no.4
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• pp.36-46
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• 1997

The present study investigated the effects of MTV(Manifold Throttle Valve) on the fuel distribution and the flame stability in a SI engine at cold, idling condition. For the quantitative measurement of fuel distribution with PLIF method, compensating techniques of various factors such as laser beam nonuniformity, background image and local OTF nonuniformity were developed. As a result, it was found that MTV had a positive effect on the air-fuel mixing and flame stability.

• Proceedings of the KIEE Conference
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• 2006.10b
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• pp.159-162
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• 2006

In this paper energy distribution function in $SiH_4$ has been analysed over the E/N range 0.5${\sim}$300Td and Pressure value 0.5, 1.0, 2.5 Torr by a two-term approximation Boltzmann equation method and by a Monte Carlo simulation. The motion has been calculated to give swarm parameters for the electron drift velocity, diffusion coefficient, electron ionization, mean energy and the electron energy distribution function. The electron energy distribution function has been analysed in $SiH_4$ at E/N=30, 50Td for a case of the equilibrium region in the mean electron energy and respective set of electron collision cross sections. 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.

• Transactions of the Korean Society of Automotive Engineers
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• v.18 no.6
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• pp.1-6
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• 2010

Aluminum rear lower arm is designed for luxury sedan and manufactured by hollow sand casting in the present study. Here we present the relationship between local microstructure and coupon tensile test in the rear lower arm. The characteristics of the local tensile deformation are supposed to be dependent upon Si distribution and DAS (dendrite arm spacing). Si distribution affects the yield strength and DAS affects the elongation of local area in the part, respectively.

• Korean Journal of Plant Taxonomy
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• v.41 no.3
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• pp.280-286
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• 2011

The natural habitats and distribution of five rare plants were recently discovered in Korea. Salomonia oblongifolia DC., which grows in mountain wetlands, was found in Gijang-gun, Busan, Gokseong-gun, Jeollanam-do, and Shinan-gun, Jeollanam-do. Glaux maritima var. obtusifolia Fernald, which grows along the coast, was found in Yangyang-gun, Gangwon-do, Pohang-si, Gyeongsangbuk-do and Buk-gu, Ulsan. Tillaea aquatica L. and Limosella aquatica L., which was previously not known to be present in Korea, were discovered in Gijang-gun, Busan for the first time. Apocynum lancifolium Russanov, which has a narrow distribution range in Korea, was also found in Samcheok-si, Gangwon-do, Ansan-si, Gyeonggi-do, Siheung-si, Gyeonggi-do, Jung-gu, Incheon, Yeongdeok-gun, Gyeongsangbuk-do and Shinan-gun, Jeollanam-do.

• Journal of the Korean Ceramic Society
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• v.45 no.9
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• pp.512-517
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• 2008

In this study, yttrium-doped $SiO_2$ nanoparticles are synthesized using a reverse micelle technique combined with metal alkoxide hydrolysis and condensation. Spherical Y-doped $SiO_2$ nanoparticles with a uniform size distribution are prepared using selfassembly molecules in conjunction with the hydrolysis and condensation of organometallic precursors. The water/surfactant molar ratio influenced the Y-doped $SiO_2$ particles distribution of the core-shell composite particles and the distribution of Y doped $SiO_2$ particles was broadened as the water to surfactant ratio increased. The particle size of Y increase linearly as the $Y(NO_3)_3$ solution concentration increased. The average size of the cluster was found to depend on the micelle size, the nature of the solvent, and the concentration of the reagent. The effects of synthesis parameters, such as the molar ratio of water to surfactant and the molar ratio of water to TEOS, are discussed.