• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.6
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• pp.1361-1368
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• 2009

This study attempts to present investment priorities and select industry for regional economic reinvigorating by analysing regional inter-industry of Chungchong area(including Chungnam and Chungbuk region) After the regional inter-industry table of Chungchong area has been made using a location quotient(LQ) method based on national inter-industry table of 2006 derived from national inter-industry table of 2003 using RAS method, various kind of impacts to Chungchong area are analysed. Manufacturing has the highest result in the result of production-inducing effect and value-added-inducing effect and hotels and restaurants has the highest result in employ-inducing effect. Sensitivity coefficient is highly analysed in mining and quarrying and influential coefficient is highly analysed in manufacturing.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.20 no.11
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• pp.925-931
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• 2007

We successively fabricated the Ni metal mask by additive method and evaluated the effects of wetting agents addition on the microstructure, hardness, and friction coefficient. In the process, the additive patterns with fine hole and pitch were made by photolithography technique and subsequently Ni plate was electroformed on the patterns. We found that the microstructure and mechanical properties were significantly varied when the different combinations of the wetting agents were used. When the wetting agents of both SF-1 and SF-2 were added, the microstructure consisted of crystal and amorphous phases, the grain size reduced to 5-40 nm, the RMS value decreased to 11.4 nm and the wear resistance improved. In addition, the hardness was as high as 638 Hv which is higher than that of commercial stainless steel mask and this improvement is probably due to the presence of amorphous Phase and fine grain size. The improvement of the wear resistance can provide a higher reliability and a longer service life.

• Korean Journal of Materials Research
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• v.32 no.6
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• pp.287-292
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• 2022

Magnesium-antimonide is a well-known zintl phase thermoelectric material with low band gap energy, earth-abundance and characteristic electron-crystal phonon-glass properties. The nominal composition Mg_3.8-xZn_xSb₂ (0.00 ≤ x ≤ 0.02) was synthesized by controlled melting and subsequent vacuum hot pressing method. To investigate phase development and surface morphology during the process, X-ray diffraction (XRD) and scanning electron microscopy (SEM) were carried out. It should be noted that an additional 16 at. % Mg must be added to the system to compensate for Mg loss during the melting process. This study evaluated the thermoelectric properties of the material in terms of Seebeck coefficient, electrical conductivity and thermal conductivity from the low to high temperature regime. The results demonstrated that substituting Zn at Mg sites increased electrical conductivity without significantly affecting the Seebeck coefficient. The maximal dimensionless figure of merit achieved was 0.30 for x = 0.01 at 855 K which is 30% greater than the intrinsic value. Electronic flow properties were also evaluated and discussed to explain the carrier transport mechanism involved in the thermoelectric properties of this alloy system.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.3
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• pp.620-626
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• 2021

The purpose of this study is to examine the characteristics and industrial structure and to present a future vision through analysis of industrial agglomeration, growth, and industrial efficiency targeting the Chungnam display industry nurtured by regional industrial policies since 2002. The industrial scale and aggregate status were analyzed through the business scale quotient and location quotient, and the growth and pace of structural change in the industry were analyzed through the industrial growth rate and change of industrial structure. Analysis results found the display industry shows its solid status based on industrial agglomeration. The RLQ, added value ratio, and employment coefficient have a relatively high comparative advantage. However, the growth rate has declined, and the pace of structural change has become lower. The regional competitiveness has been deteriorating. It is necessary to develop strategies to help the industry evolve into a convergence display industry to secure competitiveness by forming value chains. The regional industrial policy 'Regional Innovation Growth Plan' should be utilized to foster local industries that consider the regional characteristics and development directions and to promote the shared growth of related subsidiary industries through fostering specialized complexes for materials, parts, and equipment.

• The Journal of the Korea Contents Association
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• v.21 no.12
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• pp.363-374
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• 2021

The purpose of this study is to analyze how much the mining industry contributes to the Mongolian national economy using the 2019 input-output table released by Asian development bank/ERCD in 2021 to understand the characteristics of the Mongolian economy and to use it as a reference. For this study, the Mongolian economy was classified into 35 industries and the contribution of the national economy was analyzed. As a result of the analysis, the total production inducement amount of the Mongolian mining industry was $38,418 million, the total production inducement coefficient was 1.473, the index of sensitivity of dispersion was 1.696, the value added inducement coefficient was 0.707, and the production inducement coefficient was 1.473. It can be seen that the Mongolian mining industry has a higher production inducement effect than other industries, and has great potential for development as a strategic industry leading other industries.

• Journal of Korean Tunnelling and Underground Space Association
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• v.15 no.4
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• pp.401-413
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• 2013

Slurry shield tunnelling ensures stability by pressurizing the tunnel face with the slurry contained in the chamber. It resists water and earth pressure in order to prevent the failure in the tunnel face during tunnel excavation. If the ground is relatively coarse, slurry can not clog the tunnel face and excessive slurry infiltration will occur. In this case chemical compounds or additives should be added to the slurry in order to improve the clogging phenomena at the tunnel face. In this study, the effect of the carbon dioxide gas as an additive to the slurry instead of chemical compounds on the capability of enhancing the clogging in the tunnel face is investigated. Bubbles arising from the carbonate-added slurry are trapped in the soil voids enhancing the clogging capability. This effect is studied in this paper by performing laboratory model tests simulating in-situ conditions, and by adopting the fine particle clogging theory. Tunnel face stability analysis was also performed and it was found that the effective size ($D_{10}$) of soils which can guarantee tunnel stability utilizing the carbonate-added slurry increased from 1.0 mm up to 2.6 mm. Moreover, Stability analysis showed that the tunnel face is stable if the ${\lambda}$(deposition coefficient) value is greater than $0.007sec^{-1}$.

• Korean Journal of Materials Research
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• v.5 no.2
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• pp.246-250
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• 1995

Microwave properties of $CaTiO_{3}$, MgO and CaO added $MgTiO_{3}$ ceramics are investigated. In the composition of $(Mg_{0.915}Ca_{0.085})TiO_3$, dielectric constant($varepsilon _T$) was 22, Qxf value was 50000, and temperature coefficient of resonant frequency($gamma_T$) approached to near zero $ppm/^{\circ}C$.$MgTiO_{3}$ ceramics with 0.1 mol of MgO showed the highest Qxf calue of 131000, dielectric constant of 17, and r, of -$50ppm/^{\circ}C$. Dielectric constant of 8 mol% CaO added to $MgTiO_{3}$-MgO was 20. Qxf valus was 52000, and sf was zero $ppm/^{\circ}C$. $MgTiO_{3}$-Mg0-Ca0 system showed higher Qxf value than ($Mg_{1-x}, Ca_x$) Ti03 system.

• Journal of the Korean Applied Science and Technology
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• v.30 no.2
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• pp.204-214
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• 2013

This research was performed to evaluate Vibrio fischeri toxicity for TNT-contaminated soils treated by composting and slurry phase bioreactor, which were operated for 45 and 200 days, respectively. In case of composting, the GL value of acetone-added soil was 40, which was lower than th at of glucose-added soil after treatment. In case of slurry phase bioreactors under anaerobic, anaerobic/aerobic, and aerobic regimes, they showed the GL values of 6, 8, and 4 after treatment, respectively. It was evaluated that the toxicity of all slurry phase bioreactors was reduced significantly to detoxification. The relationships between GL value and the number of S. typhimurium in both composting and slurry phase bioreactor were developed as the first order equations with high correlation coefficient (r > 0.8890).

• Proceedings of the KIEE Conference
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• 2000.07c
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• pp.1474-1476
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• 2000

The mechanical and electrical properties of the hot-pressed and annealed $\beta$-Sic-$ZrB_2$ electroconductive ceramic composites were investigated as function of the liquid forming additives of $Al_{2}O_{3}+Y_{2}O_{3}$. Phase analysis of composites by XRD revealed $\alpha$-SiC(6H), $ZrB_2$, and YAG($Al_{5}Y_{3}O_{12}$). The relative density of composites were increased with increasing $Al_{2}O_{3}+Y_{2}O_{3}$ contents. The flexural strength showed the highest value of 390.6MPa for composites added with 20wt% $Al_{2}O_{3}+Y_{2}O_{3}$ additives at room temperature. Owing to crack deflection, crack bridging. phase transition and YAG of fracture toughness mechanism. the fracture toughness showed the highest value of 6.3MPa${\cdot}m^{1/2}$ for composites added with 24wt% $Al_{2}O_{3}+Y_{2}O_{3}$ additives at room temperature. The electrical resistivity of the composites was all positive temperature coefficient resistance (PTCR) in the temperature range of 25$^{\circ}C$ to 900$^{\circ}C$.

• Journal of Information Science Theory and Practice
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• v.10 no.spc
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• pp.66-75
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• 2022

The manufacturing industry is the foundation that drives economic growth, and manufacturing innovation is essential for sustainable growth advantage and the transition into a digital economy. Therefore, major countries actively support the field of simulations, which incorporate information and communication technologies into manufacturing, and announce various policies at the national level along with increasing investment. Simulation technology virtualizes product development processes to replace physical production and experimentation of products, dramatically reducing time and costs. In South Korea, the Korea Institute of Science and Technology Information (KISTI) has supported manufacturing companies for about 14 years by providing relevant technologies. This study uses the input-output table for the Bank of Korea to analyze the economic ripple effect. First, we identified the domestic industrial sector dealing with the supercomputing-based simulation industry. Then we analyzed its ripple effects by dividing them into the production inducement effect, value-added inducement effect, employment inducement effect, and forward/backward linkage effect. Consequently, when the supercomputing simulation budget of KISTI (28.3 billion won, 2007-2020) was set as an input coefficient, the analysis showed 45.1 billion won as the production inducement effect, 24.7 billion won as the value-added inducement effect, and 282 individuals per 1 billion won as the employment inducement effect. This study is significant in that it derived the effects of the inputs by analyzing the economic ripple effects of the projects of KISTI, which have been supporting South Korean manufacturing companies for the past 14 years with supercomputing-based simulations.