• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.1
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• pp.249-255
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• 2014

This paper deals with measurement on the economic impact of tax-free oil for Agriculture in Korea. According to increasing of world oil price, the supply policy of agricultural tax-free oil, which specified to support farmers since 1986, are required to expand by farmers. But the supply quantity of tax-free oil is deceased continuously and Korean Ministry of Trade, Industry, and Energy(MOTIE) present stance of sundown policy of tax-free oil for agriculture. In this context, It is necessary and important to measure the economic impact of the supply policy of tax-free oil for agriculture. This study address a econometric method for measurement the economic impact of the supply policy of tax-free oil and suggest several policy implements. Our results show that when the supply policy of tax-free oil for agriculture is annihilated in phases over the five years. the agricultural GDP is decreased by about 3,195 billion korean won and the agricultural price level is increased by 26.6 points after 5 years.

• Journal of IKEEE
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• v.20 no.2
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• pp.181-183
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• 2016

In this work, the merged PiN Schottky(MPS) diodes based silicon carbide(SiC) have been optimized and designed for 1200V diodes by 2D-atlas simulation tool. We investigated the optimized characteristics of SiC MPS diodes such as breakdown voltage and specific on-resistance by varying the doping concentrations of P-Grid/epi-layer and space of P-Grid, which are the most important parameters. The breakdown voltage and specific on-resistance, based on Baliga's Figure Of Merit (BFOM), have been compared with and the SiC-based MPS diodes show improved BFOMs with low values of specific on-resistance and high breakdown voltage. It has been demonstrated 1,200 V SiC MPS diodes will find useful applications in high voltage energy-efficient devices.

• Journal of The Korean Association of Information Education
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• v.19 no.2
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• pp.167-174
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• 2015

A recent increase of interests on the influence of 3D printing and low prices of 3D printers makes a high possibility of 3D printer adoption as a educational equipment in public education settings. The Ministry of Science, ICT and Future Planning and Ministry of Trade, Industry and Energy proposed '3D printing industry development strategies', and had pilot schools to include understanding of 3D printing concepts and practices in the primary, secondary and high schools' curriculum. However, even if 3D printers were provided in educational settings, the research on educational content and methods to properly react to this change is very limited. Therefore, this study reviewed various 3D modeling software because a modeling skill is a prerequisite skill to use 3D printers, and proposed a creative design spiral based teaching content that can be incorporated in elementary school contexts.

• Journal of Korea Water Resources Association
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• v.50 no.7
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• pp.467-473
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• 2017

Recently as algae phenomenon has been intensified, the need for additional dam flushing has been raised. To establish the more rational policies concerning the dam flushing, it is necessary to evaluate the dam flushing. This paper attempts to examine households' willingness to pay (WTP) for dam flushing by using a contingent valuation (CV). Especially, unlike other CV studies which used maximum likelihood estimation (MLE), this study employed Bayesian approach. This study surveyed a randomly selected sample of 1,000 households nation-widely, and asked respondents questions in person-to-person interviews about how they would be willing to pay for the additional dam flushing. Respondents overall accepted the contingent market and were willing to contribute a significant amount (1,909.4 won), on average, per household per year. The aggregate value amounts to approximately 35.7 billion won per year.

• Journal of Korea Technology Innovation Society
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• v.13 no.3
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• pp.459-470
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• 2010

The aim of this study were to investigate the process of national R&D project planning by using the industry quantitative analysis(especially supply-chain enterprise ananlysis). In the selection process of funding project, the role and significance of the industry analysis can be identified as the effective guideline of using this methodology. Across the study, the following is noted : the factors of R&D effectiveness and R&D necessity are found reliable and valid. On the other hand, the emptiness of supply chain and the positive effect of foreign trade balance did not influence the selection of project. The information gained from this study will help us to define better expectations and industry analysis employing to the National R&D Project Planning.

• 한국신재생에너지학회:학술대회논문집
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• 2009.06a
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• pp.491-494
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• 2009

This paper introduces the design concepts and characteristics of WinDS3000$^{TM}$ which is a trade mark of Doosan's 3MW offshore/onshore wind turbine. WinDS3000$^{TM}$ has been designed in consideration of high RAMS (Reliability, Availability, Maintainability and Serviceability) and cost effectiveness for the TC Ia condition in GL guideline. An integrated drive train design with an innovative three-stage gearbox has been introduced to minimize nacelle weight of the wind turbine and to enhance a high reliability for transmission. A permanent magnet generator with full converter system has been introduced to get higher efficiency in part load operation, and grid friendliness use of 50 Hz and 60 Hz grid. A pitch regulated variable speed power control with individual pitch system has been introduced to regulate rotor torque while generator reaction torque can be adjusted almost instantaneously by the associated power electronics. An individual pitch control system has been introduced to reduce fatigue loads of blade and system. The wind turbine has been also equipped with condition monitoring and diagnostic systems in order to meet maintainability requirements. And internal maintenance crane in nacelle has been developed. As a result, the maintenance cost was dramatically reduced and maintenance convenience also enhanced in offshore condition.

• International Journal of Automotive Technology
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• v.8 no.6
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• pp.761-769
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• 2007

The configuration of the flow channel on a bipolar plate of a proton exchange membrane fuel cell(PEMFC) for efficient reactant supply has great influence on the performance of the fuel cell. Recent demand for higher energy density fuel cells requires an increase in current density at mid voltage range and a decrease in concentration overvoltage at high current density. Therefore, an interdigitated flow channel where mass transfer rate by convection through a gas diffusion layer is greater than the mass transfer by a diffusion mechanism through a gas diffusion layer was recently proposed. This study attempts to analyze the i-V performance, mass transfer and pressure drop in interdigitated flow channels by developing a fully three dimensional simulation model for PEMFC that can deal with anode and cathode flow together. The results indicate that the trade off between performance and pressure loss should be considered for efficient design of flow channels. Although the performance of the fuel cell with interdigitated flow is better than that with conventional flow channels due to a strong mass transfer rate by convection across a gas diffusion layer, there is also an increase in friction due to the strong convection through the porous diffusion layer accompanied by a larger pressure drop along the flow channel. It was evident that the proper selection of the ratio of channel and rib width under counter flow conditions in the fuel cell with interdigitated flow are necessary to optimize the interdigitated flow field design.

• Journal of Conservation Science
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• v.34 no.4
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• pp.305-311
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• 2018

The yellow crystalline material present in yellow and green glass beads excavated from sites in the Baekje region of Korea was previously analyzed through scanning electron microscopy with energy dispersive spectroscopy and X-ray diffraction, revealing that the yellow crystalline material was $PbSnO_3$. This material is a pigment that is rarely seen in the Korean peninsula. Furthermore, some studies have been published on the provenance of lead in this material, which revealed no relationship to Korea, China, or Japan. In this study, we collected all accessible results of analyses on the lead isotope ratio of yellow and green glass beads excavated from the Korean peninsula, specifically from 7 sites in the Baekje region(located in the vicinity of Seoul, Wanju, Hwaseong, Osan, Gongju, Buyeo, and Iksan) and 2 sites in the Silla region(located in the vicinity of Gyeongju and Changnyeong). We subsequently investigated the lead provenance of the opacifying agents in the glass beads through comparison with the current extent of the galena data accumulated for the East Asian region, including Korea, China, and Japan, and for Thailand(Kanchanaburi Province), Southeast Asia. Our analysis determined that the lead provenance of the glass beads excavated from the Korean peninsula was Thailand(Kanchanaburi Province). Beyond our results, further studies should seek to determine the production sites of the glass beads. Obtaining and comparing the scientific analyses of glass beads from India and Southeast Asia would enable research on the glass beads trade through the maritime silk road.

• Journal of Distribution Science
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• v.4 no.1
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• pp.161-173
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• 2006

The most important two decision-makings which a retail store owner face require which place of the store should geographically be established and which stock should be properly placed on the shelves. The problem of geographic positioning is the decision-making for the store's positioning and stock arrangement within the retail store is the decision-making for the placement store. In order to determine the positioning, the expected area should be analyzed so that the analysis of commercial area can usually be implemented in accordance with retail marketing strategy and therefore the sized of the potential market for example each distric's clientele, competition and, a municipal community's regulations, could be evaluated. But I contend that with only the size of potential market does not give an adequate answer to the problem of a store's positioning. Through the estimation of commercial are in combination with feng-shui, the theory of divination based on topography, the store's position could be selected, taking a positive energy, Gi. This thesis is the starting point of these trials. In the long run, the actual analysis of the study should be continued in a more scientific, systematic, statistical way.

• Management & Information Systems Review
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• v.29 no.2
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• pp.53-73
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• 2010

SCEM is the concept of reducing environmental effect on the outside of purchasing and manufacturing process, delivery, and distribution process. An ultimate aim of SCEM are obtaining environmental stability and energy/materials operational efficiency. Although the importance of greening supply chain was highlighted, former researches were often based on case studies of specific industry and didn't provide clear definition of environmental supply chain management which includes fundamental notions for business practitioners. This study focuses on findings how the SCEM system practically run and what the characteristics of SCEM is in Korean firms through case studies. It is suggested that SCEM is more effective for environmental management rather than by making limited eco-innovation. Korean firms have considered that an international environmental regulation is more important than customers' needs for environmental goods for implementing SCEM.