• Journal of the Economic Geographical Society of Korea
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• v.15 no.2
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• pp.292-303
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• 2012

The main purpose of this study is to analyze R&D networks and spatial implications in Qingdao consumer electronics industry agglomeration in China. The characteristics of R&D networks in Qindao consumer electronic industry are as follows. There is a cluster central around large enterprises led by the government and their subcontracting enterprises. However, the degree of collaborative networks in intra-firm, inter-firm, firm-research institutes(including university lab.) is relatively low. Therefore, Large enterprises in Qingdao has stimulated research collaborations with firms and research institutes located in other regions rather than within region. It is likely to show that R&D networks of consumer electronics industry has not been stimulated in Qingdao. Therefore, collaborative R&D networks among firms, research institutes and governments should be stimulated to build regional innovation systems central around consumer electronics industry in Qingdao.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.11 no.6
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• pp.290-296
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• 2001

Fin metal particles of uniform shape, narrow size distribution and high purity are increasingly needed for specific uses in high tech industrial applications. Polyol process for the preparation of monodispersed cobalt powders in micron size is described. In this process in inorganic precursor is reduced in liquid polyol under controlled conditions. The reducing agent is the polyol itself and reaction parameters such as the traction temperature, reaction time, addition of protective agent and concentration of the precursor are varied for controling particles size, shape and agglomeration of the metal particles. An optimum synthesis condition was achieved at E.G/DiE/G volume ratio 1:4,Co$(OH)_{2}$polyol molar ratio 0.08~0.32 reaction temperature $210^{\circ}C$, PVP/Co$(OH)_{2}$ molar ratio 0.4.

• Journal of the Economic Geographical Society of Korea
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• v.12 no.4
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• pp.576-596
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• 2009

Recently the World Bank released its World Development Report 2009 (hereafter WDR 2009) with the title 'Reshaping Economic Geography.' In the report, the Korean experience in regional development policy was highly praised. Also, the current government has been trying to reshape the regional development policy in view of 5+2 Economic Regions. The main theme of this paper is how to establish the highly valueadding economic system and how to deal with scale economies for regional development. In this paper these tasks in Korea's regional policy were discussed with reference to the WDR 2009. Enhancing the density of the central city of each Economic Region, reducing the economic distance between cities and rural areas, and getting rid of the barriers to cooperation between provinces are the keys for the efficiency and the effectiveness of the regional policy. In addition, strengthening the national solidarity through collaborative development of 5+2 Economic Regions still remains as one of the major tasks of the Korean government.

• Applied Chemistry for Engineering
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• v.25 no.3
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• pp.300-306
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• 2014

In this study, we investigated the noble metal catalysts for HCHO removal at room temperature. These catalysts were characterized by XRD, FT-IR, CO-chemisorption. As a result, Pt and Pd based catalysts prepared by the reduction treatment showed the superior HCHO oxidation ability at room temperature. When the catalysts were prepared using $TiO_2$ support, which is well known as the reducing support, showed the superior activity. Also, the activity decreased by the agglomeration of active metal with increasing the reduction time. In case of reduction catalysts, it has been confirmed that the desorption and adsorption ability properties of HCHO is excellent at room temperature.

• Applied Chemistry for Engineering
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• v.30 no.2
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• pp.167-177
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• 2019

The jadeite powder has a disadvantage affecting the stability of the formulation due to the agglomeration of the powder when applied to cosmetic formulations. To overcome this problem, a new composite powder was prepared by modifying the surface of jadeite powder and applied to foundation pact and sun stick. In this study, a triethoxycaprylylsilane among various surface modifiers was selected as an optimum component, and applied to each formulation by making the jadeite powder composite. As a result, the foundation pact maintained the clarity of the product color, and the sun stick gave about 30% higher UV blocking effect in the UVB area compared with that of the blank. In the user sensory evaluation, the formulation containing the jadeite powder composite showed a high score for the overall indicator. The stability evaluation of the formulation was also confirmed that it was stable against discoloration, detachment and hardness. In conclusion, the jadeite powder composite is stable as an inorganic pigment which is applicable to cosmetics as a multifunctional material while maintaining the color clarity of the product and acting as a booster for sunscreen agents.

• Applied Chemistry for Engineering
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• v.30 no.2
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• pp.178-185
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• 2019

Three spherical quaternary composites composed of metal/metal oxide/high explosive/oxidizer were prepared by a crystallization/agglomeration process. From the characteristics of composites by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC), the shortening of the decomposition zone of high explosives in the quaternary composite was observed, which may be attributed to the autocatalytic reaction caused by $ClO_2$ or HCl which are ammonium perchlorate (AP) degradation products. The activation energy analysis showed that the activation energy abruptly decreases at the end of the decomposition zone of high explosives, and it was considered to be caused by $HNO_2$ which is common in decomposition products of high explosives. The activation energy predicted from complex pyrolysis results by the distributed activation energy model (DAEM) showed much better in accuracy than those by model-fitting methods such as Kissinger-Akahira-Sunose and Flynn-Wall-Ozawa models.

• Analytical Science and Technology
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• v.32 no.3
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• pp.77-87
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• 2019

High viscosity carbon black dispersions are used in various industrial fields such as color cosmetics, rubber, tire, plastic and color filter ink. However, carbon black particles are unstable to heat due to inherent characteristics, and it is very difficult to keep the quality of the product constant due to agglomeration of particles. In general, particle size analysis is performed by dynamic light scattering (DLS) during the dispersion process in order to select the optimum dispersant in the carbon black dispersion process. However, the existing low viscosity analysis provides reproducible particle distribution analysis results, but it is difficult to select the optimum dispersant because it is difficult to analyze the reproducible particle distribution at high viscosity. In this study, dynamic light scattering (DLS) and asymmetrical flow field-flow fractionation (AsFlFFF) analysis methods were compared for reproducible particle size analysis of high viscosity carbon black. First, the stability of carbon black dispersion was investigated by particle size analysis by DLS and AsFlFFF according to milling time, and the validity of analytical method for the selection of the optimum dispersant useful for carbon black dispersion was confirmed. The correlation between color and particle size of particles in high viscosity carbon black dispersion was investigated by using colorimeter. The particle size distribution from AsFlFFF was consistent with the colorimetric results. As a result, the correlation between AsFlFFF and colorimetric results confirmed the possibility of a strong analytical method for determining the appropriate dispersant and milling time in high viscosity carbon black dispersions. In addition, for nanoparticles with relatively broad particle size distributions such as carbon black, AsFlFFF has been found to provide a more accurate particle size distribution than DLS. This is because AsFlFFF, unlike DLS, can analyze each fraction by separating particles by size.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.5
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• pp.708-715
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• 2017

Recently, in order to meet the stricter emission regulations, the proportion of after-treatments for vehicles and vessels has been increasing gradually. The objective of this study is to investigate the improvement of $CH_4$ reduction ability of natural gas oxidation catalyst (NGOC), which reduces toxic gases emitted from CNG buses. Thirteen NGOCs were prepared, and the conversion performance of noxious gases according to the type of supports, the loading amount of noble metal, and surfactant and aging were determined. Support Zeolite supported on No. 3 $NGOC(1Pt-1Pd-3MgO-3CeO_2/(46TiO_2+23Al_2O_3+23Zeolite)$ is an anionic alkali metal/earth metal component that improved the oxidation reactivity between CO and NO and noble metal dispersion, and thus enhanced the $CH_4$ reduction ability. As the loading amount of Pd, a noble metal with a high selectivity to $CH_4$, was increased, the number of reaction sites was increased and the ability to reduce $CH_4$ was improved. No. 11 $NGOC(1Pt-1Pd-3MgO-3CeO_2/(Z20+Al80)$(pH=8.5), to which nitrate surfactant had been added, exhibited well dispersed catalyst particles with no agglomeration and improved the $CH_4$ reduction ability by 5-15%. The $NGOC(2Pt-2Pd-3Cr-3MgO/90Al_2O_3)$(48h aging), which was mildly thermal aged for 48h, increased the $CH_4$ reduction ability to about 10% or less as compared with No. 12 NGOC(Fresh).

• Journal of the Korean Geographical Society
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• v.28 no.1
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• pp.16-39
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• 1993

This study aims to analyze the locational factors which the small firm enterpreneurs in Pusan City mainly consider in deciding location choices for their plants, and then to grasp the differences of the factors in terms of nature of firms, managerial personal characteristics and zoning areas. In order to implement the purpose of the rescarch, data are collected from selected small firm enterpreneurs throughthe questionaire. The main results are summerized as follows. First, it is pointed out that small firm indu-strialists for the regional choice consider crucial rationale as non-economic factor of personal reson with additional consideration of transpor-tation, infrastructure, service, market and labor forces. But in selection of site, they are apt to have high regard on the such factors as infra-structure, service, land and transportation factor. These factors to select the site demonstrate differentiation in terms of character of enter-prises, managerial characteristics and zoning areas. For example, land in the light of indu-strial sector is regarded as an important factor with longer the time of the establishment of firms or more aged or experienced enterpreneurs, wheras infrastructure and service in the heavy and chemical industrial sector are taken up as an important one with shorter the time of establishment of firms or less aged or experienced or higher educational background of enterpren-eurs. In addition, the non-economic factors such as the residential livebility and personal reason are picked up as important factors with smaller the firm or more aged or experienced, lesser educational background of entrepreneurs. Taking into consideration zoning area, infra-structure and service in the industrial area such as the exclusive and semi-industrial areas, land in green belt area, and transportation in the commercial and residential areas are singled out as the most important factors respectively. In addition, the non-economic factors of the resi-dential livability and personal reason in the non-industrial areas are also highly regarded. Second, land is picked up as the most impor-tant one of pulling factors toward the present site while other factors such as infrastructure, service, personal reason are also regarded as the secondary reason for the move-in decision; the pulling factors for the present plant location show somewhat differences in terms of the charcter of the enterprises, managerial chara-cteristics and zoning areas. Policy measures including land, infrastructure under the environmental aspects, service and transportations are, in turn, pointed out as the important ones for pushing factors. Meanwhile, as the important staying factor in the present place, transportation, infrastructure and service under the aspect of the agglomeration benefit, market, personal reason are considered. The pushing and staying factors also shows somewhat distinctive differences in terms of the character of enterprises, managerial chracteristics and zoning area. In the case of zoning area, land is regarded as the most important factor to move out, especially in the non-industrial areas inclu-ding the commerical and residential areas policy measures, infrastructure and service are indicated as important factors to move out. In the mean-time, as the important staying factor, industria-lists in the exclusive and semi-industrial areas point out transportation, infrastructure and service. Whereas the counterparts in the com-mercial area regard transportation and market as important factor, those in the residential area consider the non-economic factors such as personal reason and residential livability. Taking into consideration the result of this analysis, it is identified that the locational chara-cteristics of the intraurban small firm industries are not only associated with the character of enterprises, but also with manager's personal character and the trait of zoning area. Therefore, it seems that the thorough review or examination of enterprises, industrialists' characteristics and zoning areas will have meanin-gful significance in attemption explanation of small firm industries at the intrauban scale in the future. Especially, it appears that the eco-nomic factors such as land, infrastructure, service, transportation, and the non-economic factors such as residential livability and personal reason play together important parts to determine the locational choice of small firm industries along with non-industrial benefit. Thus, such status reveals the obvious implication for the intraurban industrial policy in the future.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.11
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• pp.537-543
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• 2019

Alumina(Al₂O₃) is a ceramic material used in industry with a range of particle sizes and characteristics. In this study, a boehmite sol was prepared by a hydrolysis and peptizing process using the Sol-Gel method from aluminum isopropoxide (AIP). γ-Al₂O₃ was prepared by drying and calcining. To prevent particle agglomeration during the manufacturing process, four kinds of polyvinyl alcohol (PVA) with molecular weights of 9,000~10,000, 31,000~50,000, 89,000~98,000, and 130,000 were added and three concentrations of HNO₃ (0.1, 0.3, 0.5 molar ratio) were added to determine their effects on the particles. The crystal structure, composition, particle size and shape of the prepared γ-Al₂O₃ were confirmed through x-ray diffraction (XRD), x-ray fluorescence analyzer (XRF), particle size analyzer (PSA), and field emission scanning electron microscopy (FE-SEM). As a result, γ-Al₂O₃ with a purity of approximately 98.2% was synthesized, and the particle size decreased and the uniformity increased with increasing ratio of HNO₃ addition and PVA molecular weight. From these results, the particle size can be controlled during the manufacturing process of γ-Al₂O₃ by controlling the addition ratio of PVA and HNO₃.