• The Transactions of The Korean Institute of Electrical Engineers
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• v.67 no.11
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• pp.1542-1548
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• 2018

When any faults occurred in electrical railway system, operators need to analysis it quickly and accurately. Existing COMTRADE based analysis tools are not enough to analysis faults occurred in electrical railway system. In this paper, it presents some functions to fault analysis for electrical railway system based on fault data formatted COMTRADE. These functions are implemented in PSCAD/EMTDC and it can be shown that analyzed results against actual electrical fault cases which were occurred in the electrical railway power system.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.62 no.3
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• pp.151-158
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• 2013

Large generator of power plant is very important. In order to protect large generator from faults, digital protective relay or IED is required. However, all protective relays for generators of the domestic power plant are operated by foreign products. And now, for technological independence from foreign and improvement of import substitution effect, IEDs using domestic technology are being developed. To evaluate performance of developing next-generation power devices, the study of the dynamic characteristics of the power plant, generator system modeling, fault simulation and analysis, should be considered. Specially, To obtain IEEE Standards COMTRADE format for relay operation test, generator system modeling and fault simulation using PSCAD/EMTDC tools must be preceded. Until now, a complete modeling of generator internal windings and fault simulation techniques dose not exist. In this paper, for evaluation performance of relay elements of developing IED, the generator system modeling and various faults simulation using PSCAD/EMTDC tools were performed. And then, the various transient phenomena through obtained relaying signal of developed modeling were analyzed.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.65 no.1
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• pp.47-52
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• 2016

Fault location identification in the transmission line is an essential part of quick service restoration for maintaining a stable in power system. The application of digital schemes to protection IEDs has led to the development of digital fault locators. Normally, the impedance measurement had been used to for the location detection of transmission line faults. It is well known that the most accurate fault location scheme uses two-ended measurements. This paper deals with the complete design of a fault locator using GPS time-synchronized phasor for transmission line fault detection. The fault location algorithm uses the transmitted relaying signals from the two-ended terminal. The fault locator hardware consists of a Main Processor Unit, Analog Digital Processor Unit, Signal Interface Unit, and Power module. In this paper, sample real-time test cases using COMTRADE format of Omicron apparatus are included. We can see that the implemented fault locator identified all the test faults.

• International Area Studies Review
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• v.20 no.4
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• pp.3-22
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• 2016

This study analyzed the pattern of Myanmar's trade with east asia countries, Korea, China and Japan. By using RCA index and TSI index, the comparative advantage and trade specialization of Myanmar are analyzed. UN COMTRADE data from 2012 to 2014 is analyzed. After the economic sanction against Myanmar was lifted, the volume of trade of Myanmar was increased sharply as well as the trade structure is changed. The volume of trade in primary industry is decreased while the manufactured industry takes more share of trade volume. The comparative advantage of manufactured industries took more steps while those of primary industries lose. In the trade with Korea, China and Japan, Myanmar exports labor intensive products and primary goods. Trade relationship beteen Korea and Myanmar is analyzed to be primary step, while China's and Japan's are going to be advanced. China and Japan are entering to the stage of international value chain system by using abundant labor of Myanmar.

• Resources Recycling
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• v.30 no.3
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• pp.63-69
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• 2021

Supply deficit of lead commodities and environmental pollution can be simultaneously resolved through the recovery and recycling of waste lead. The recent recovery of lead through recycling of the lead battery waste is a positive development. To maximize the effect of lead recovery and recycling in the future, the updated status of the lead material flow should be recognized. However, such an analysis at the preliminary stages may be cumbersome owing to the complexity and diversity of emission sources and material streams. At this stage, a preliminary screening by domestic lead flow using public information should be feasible. Therefore, in this study, using the data from the UN Comtrade and domestic PRTR (Pollutant Release and Transfer Register) databases, the amounts of lead import, emission, and transfer were identified and cross-checked with the domestic lead flow described in the National Material Flow Analysis database. The lead flow for major categories such as waste lead-acid batteries showed a rough consistency between the databases.

• Fashion, Industry and Education
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• v.14 no.1
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• pp.1-9
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• 2016

This study examined the comparative advantage of manmade textile (MMT) industries in the United States (US) and South Korea (SK). The Revealed Comparative Advantage (RCA) framework was used to assess the MMT industries' performance in both countries from 2004 to 2013. With the recent ratification of the United States-South Korea Free Trade Agreement (KORUS FTA), it is important to understand the current state of these industries. Using UN Comtrade export data, the RCA index values were calculated and analyzed for 27 MMT commodities, three aggregate groups, and the whole industry. It was found that SK had a consistent comparative advantage for the whole industry. Furthermore, SK had a larger number of products with a comparative advantage. The research findings indicate that the MMT industry in SK is likely to outperform the US following the complete ratification of the KORUS FTA.

• International Commerce and Information Review
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• v.10 no.1
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• pp.295-314
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• 2008

I compared trade structure and competitiveness by sector using industrial classification in UN Comtrade data and SITC. Based on the comparison, I calculated market share, export competitions, RCA, and TSI. and then selected sensitive industries based on competitiveness, and identified the ZOPA and our BATNA. These calculations confirmed the industries damaged by FTA and those benefiting from the FTA between Korea and Japan, the study them developed strategies for VIA negotiation. It is to minimize damages to Korean economy and to maximize benefits from the agreement. The negotiation plan allowed an adjustment period for industries, for which damages are expected, by setting a long grace period before implementing tariffs. Based on the negotiation plan made through economic analysis, I intend. contribute to more efficient promotion of negotiation by extracting the optimal FFA negotiation plan for each manufacturing industry.

• East Asian Journal of Business Economics (EAJBE)
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• v.7 no.3
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• pp.49-61
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• 2019

Purpose - This study shows that which country has more competitiveness in aerospace industry. The reason why author choose aerospace industry for research is aerospace industry is one of major business in every country in the world instead of infant industry. Research design and methodology - In order to research this topic, there are 3 tools to analyze competitiveness in aerospace industry. To achieve analysis of competitiveness between USA and England, UN comtrade program which provides huge database including time serial data. Results - All of TSI are over zero (0) which means that from 2000 to 2018, USA aerospace industry is export specialization as USA aerospace industry has comparative advantage against England aerospace industry. All of TSI in USA are approaching to figure +1 as export specialization except 2010. Conclusions - Even though RCA value in 2000 is 6.313, however, when time goes by and they are 8.997 in 2005, 8.007 in 2010 and 8.389 in 2015 respectively and RCA value is slightly going down as figure 7 in 2018. we review above market share analysis data, USA has overpoweringly superior competitive power against British aerospace industry.

• The Journal of Asian Finance, Economics and Business
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• v.2 no.4
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• pp.13-20
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• 2015

The purpose of this research is to identify the relation between the Korean wave and Korean cosmetics export. Instead of using UN COMTRADE data as with other researches on the similar studies, this paper adopts Google Trends query index with keyword 'Korean drama'as a proxy variable for cultural trade. With controlling export determining factors such as GDPs of import and export countries, distance, R&D, and FTA, this paper examines whether the Korean wave represented by Google Trends contributes to the explosive increase of Korean cosmetics export in the recent years. Moreover, this study also investigates the possible effects of the Korean wave on export that could vary according to the different trade groups by classifying import countries into two groups: 74 countries worldwide and 9 ASEAN member countries. The results reveal that the Korean wave indeed leads to cosmetics export to ASEAN countries but show weak relation with cosmetics export to worldwide.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.7
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• pp.394-399
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• 2017

In Korean AC power railway substations, SCOTT winding transformers are under operation to have a single phase power supply together with a phase angle of $90^{\circ}$ on the secondary side of the main transformer. In the case of an internal fault of the transformer, the transformer protection relay should be cut off on the primary side, the transformer should be inoperative to the external fault of the transformer or to the normal train operation. Reducing the malfunction of the relay through an exact fault determination is very important for securing a stable power system and improving its reliability. The main transformers are protected using Buchholtz's relay and a differential relay as the internal fault detection devices, but there are some cases of the main transformer operation under the deactivation of this protection function due to a malfunction of the differential relay. In this paper, the characteristics of the SCOTT transformer and differential relay as well as the malfunctioning of the protection relays are presented. The modeling of the SCOTT transformer protection relay was accomplished by the power system analysis program and the Comtrade file from 'A substation', which was used as the input data for the fault wave, and the harmonics were analyzed to determine if the relay operates or not. In addition, an improvement plan for malfunctioning cases through wave form analysis is suggested.