• The KSFM Journal of Fluid Machinery
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• v.3 no.4 s.9
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• pp.38-43
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• 2000

Recently, KARI(Korea Aerospace Research Institute, Korea) and CIAM(Central Institute of Aviation Motors, Russia) have made an effort in developing a centrifugal compressor for a small gas turbine engine as part of a collaboration program. This compressor has been designed as a sub-component for an axial-centrifugal compression system for a small turbo-shaft engine aiming adiabatic efficiency higher than 0.81. The geometrical design requirement imposes restrictions to have high inlet hub-to-tip ratio and inlet swirl flow. In this study, the compressor has been designed using the generalized experimental data established from those compressors having pressure ratio of 3.7 to 5. From this generalized empirical correlation, desirable values of design parameters could be obtained. Subsequently, quasi-3D and 3D viscous flow analyses have been performed to ensure the adopted methodology. It is expected that the centrifugal compressor provides total pressure ratio of 4.89, corrected mass flow-rate of 1.64kg/sec, and adiabatic efficiency of 0.815 with inlet hub-to-tip ratio of 0.641. These relatively high total pressure ratio and inlet hub-to-tip ratio are the main distinctive features in this design. Besides, one of the main features of this centrifugal compressor is the adoption of a double-row bladed diffuser to effectively decelerate the transonic flow leaving the impeller. The compressor has been manufactured and will be tested in the near future.

• The Journal of the Korea Contents Association
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• v.16 no.11
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• pp.716-730
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• 2016

The meaning and role of science culture based on such values as rational thinking, creativity, critical validation has been growing in the process of discussing various social problems. In order to diffuse science culture, it is important to sustain citizen's activeness by providing contents which can induce interest on the base of two-way communication between public and experts and to support citizen activities performed voluntarily. To that end, various people such as scientist, government policymaker, communicator, those in charge of culture and art, exhibition curator should make up collaboration system and such requirement as motivation, leadership, agreement between the participants, communication, trust relationship is also to be met properly in order to proceed collaboration efficiently. This study reviews how these factors are coming true in governmental project for science culture and develops proposal for improvement on the base of opinions collected through expert meetings, interviews, workshop and data research. In addition, it explains that government must strengthen scientific cultural project personnel and lay infra such as communications hub, regional center, platform and improve the business selection method to promote competition and collaboration among project participants with reformation of reward and regulatory systems. It is performed to suggest comprehensive ways to increase efficiency of project for science culture out of not the deficit model which regard public as passive acceptant but context model or PES(public engagement in science) that take public who focus his attention and participate actively into account.

• International Commerce and Information Review
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• v.7 no.2
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• pp.97-113
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• 2005

Korea has actively promoted the Comprehensive Plan for the e-Hub. The policies of Korean government could promote the e-business environment and market conditions in legal and infrastructure terms, but not much of business itself. The reason for this limited success in the e-Trade may result from the broken linkage between government policies and business strategies as well as the business and technical innovation. In this paper, we analyzes the more effective and economic solution for this recovery of broken link in terms of Metamediary. The most successful role of metamediary should compose of three functions - facilitator, collaborator and web service provider. Each of these function is clarified in more detail with the emphasis on the collaboration between the Universities and the government-supported corporations.

• ETRI Journal
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• v.42 no.2
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• pp.196-204
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• 2020

Open-source software development projects are well suited for exploring new ideas and acquiring knowledge from developers outside of the project. In this paper, we examine the impact of external developers on innovation in open-source software development from the perspective of organizational learning theory. We examine the roles of external and internal developers, who "explore" and "exploit," respectively, on the innovation performance of 17 691 open-source software development projects whose data is stored in the GitHub platform. The results indicate that a multifaceted strategy, in which the exploitation successfully supports the exploration, is most effective for their success. The results also indicate that the role of exploration decreases after the release of the software.

• Journal of Information Technology Services
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• v.19 no.6
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• pp.177-189
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• 2020

The OECD has assessed Korea as the third highest in trade facilitation worldwide. The paperless trade of Korea is world class based on uTradeHub : national e-trade service's infrastructure for trade community. Over 800 trade-related document standards provide interoperability of message exchange and trade process automation among exporters, importers, banks, customs, airlines, shippers, forwarders and trade authorities. Most one-to-one unit processes are perfectly paperless & online; however, from the perspective of process flow, there is a lack of streamlining end-to-end trade processes spread over many different parties. This situation causes the trade community to endure repetitive-redundant load for handling trade documents. The trade community has a strong demand for seamless trade flow. For streamlining the trade process, processes with data should flow seamlessly to multilateral parties. Flowing data with an optimized process is the critical success factor to accomplish seamless trade. This study proposes four critical digital trade infrastructures as a platform service : (1) data-centric Intelligent Document Recognition(IDR), (2) data-driven Digital Document Flow (DDF), (3) platform based Digital Collaboration & Communication(DCC), and (4) new digital Trade Facilitation Index (dTFI) for precise assessment of K-Trade Digital Trade Framework. The results of new dTFI analyses showed that redundant reentry load was reduced significantly over the whole trade and logistics process. This study leads to the belief that if put into real-world application can provide huge economic gains by building a new global value chain of the K-trade eco network. A new digital trade framework will be invaluable in promoting national soft power for enhancing global competitiveness of the trade community. It could become the advanced reference model of next trade facilitation infrastructure for developing countries.

• Journal of the Korean Institute of Educational Facilities
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• v.20 no.4
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• pp.23-34
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• 2013

This study focuses on the review of the present condition of schools and regional public facilities and finds out the basic direction and practical task to utilize a mixed-use school as a regional community hub reorganizing schools and regional public facilities. School facilities have enough potential to be a center of everyday life and educational function with accessibility in neighborhood living environment. Nevertheless it has institutional limitation to make school facility work for entire region because schools and regional public facilities are built and administrated without collaboration of the local governments and office of education. Also current mixed-use school facilities are planned separately or laid out monotonously without local resident's demands. This research analyzes the possibility of mixed-use facility of current operating schools and regional public facilities in Gang-nam gu and categorizes possible public facilities for mixed-use. For successful complex plan of schools and public facilities, next step will be the improvement of administration and laws and the analysis of facilities what local residents need from the preliminary stage with consultation of various stakeholders.

• Journal of the Korean Ceramic Society
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• v.45 no.6
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• pp.345-349
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• 2008

$TiO_2$ coating ceramic tile for self-cleaning purpose was prepared by the precipitant dropping method using $TiCl_4$ as a precursor. $TiO_2$ film was formed on the ceramic tile by spray-coating technique and heat-treated at $500^{\circ}C$ for 1 h. The size and crystalline structure of $TiO_2$ particles were 15.3 nm and anatase phase. The outdoor exposure tests were conducted and the effects of outdoor exposure test conditions, such as exhaust concentration of contamination materials (test places), the UV light intensity (irradiation direction) and coating amounts of $TiO_2$ on the self-cleaning properties were investigated by the brightness measurements. As a results, self-cleaning property of $TiO_2$ coating tile was affected by the coating amount of $TiO_2$ however, not affected by the UV light intensity included in sun's ray (irradiation direction). $TiO_2$ coating ceramic tile can be utilized for exterior finishing materials because of self-cleaning property of $TiO_2$ coating tile.

• Journal of the Korean Ceramic Society
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• v.45 no.1
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• pp.43-47
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• 2008

The photocatalyst of $TiO_2$ coated on a fly ash composites (TCF) was prepared from precipitant dropping method to remove the acetaldehyde by photocatalytic reaction. The TCF were characterized by crystal aize, crystal structure and specific surface area. The photodegradation of acetaldehyde has been investigated using a UV-illuminated fixed photocatalytic reactor with TCF catalyst and P-25 catalyst in gas phase. The effect of photodegradation reaction conditions, such as initial concentration of acetaldehyde, concentration of oxidant in mixed gas and the light intensity on the photodegradation of acetaldehyde were investigated. P-25 catalyst showed the highest photodegradation of acetaldehyde and anatase $TiO_2$ coated TCF showed higher decomposition rate than rutile coated TCF. The photodegradation rate of acetaldehyde increased with the decrease of flow rate, initial concentration of acetaldehyde ($C_i$) and water vapor, however, it was increased with the increas of UV light intensity. The optimum conditions were weight of TCF=10 g, flow rate=50 ml/min $C_i$=100 ppm, concentration of oxygen=20%, concentration of water vapor=100 ppm.

• Information Systems Review
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• v.5 no.2
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• pp.53-69
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• 2003

This paper tried to find how the characteristics of purchasing items would have influence on the relational e-procurement. The characteristics of purchasing items include the importance and the complexity of purchasing items. In order to define these characteristics, this paper reviewed various literatures about purchasing strategies. The empirical analysis through the multi-nominal logistic regression shows that the importance of items has influence on relational e-procurement, while the complexity of purchasing process has little influence. And also, the relational e-procurement through EDI as a long term buying relationship is being converted toward the exchange through purchasing sites.

• Journal of the Korean Society of Clothing and Textiles
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• v.43 no.4
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• pp.491-505
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• 2019

This study analyzes global fashion clusters to provide insight for the domestic fashion market to form a competitive fashion cluster. We examine formation factors and operation types of the global fashion clusters to understand their characteristics. We also explore the effectiveness of each global fashion cluster by investigating the stage of development in fashion clusters. Fourteen cases of global fashion clusters are collected and analyzed. First, global fashion clusters show three types of formation and operation: self-formation, self-formation & government based development, and government, institute, and enterprise based formation & development. Second, the characteristics of global fashion clusters are based on functions related to space, learning, innovation, network, and knowledge. Third, there are four steps in the development stage of global fashion clusters: professional clusters, industrial clusters, learning clusters and innovative industrial clusters. In particular, innovative industrial clusters, the final stage of development, have high levels of effectiveness in terms of co-growth and collaboration among fashion-related businesses in fashion clusters. The results of this study can help guide the development of local fashion cluster in Korea.