• Journal of the Korea Organic Resources Recycling Association
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• v.23 no.2
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• pp.11-18
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• 2015

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.29 no.6
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• pp.96-108
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• 2015

his study deals with a power conversion unit of an anti-start air conditioner compressor system for the commercial vehicle. In case of converter, to reduce the switching losses and current stresses of the device, applies LLC resonant topology. Transformer leakage inductance in the full-bridge converter is used for making the resonance with the capacitor of the voltage-doubler. Through this method we can increase power and decrease volume of system. Both circuit analysis and design guideline are described. So in this paper, power conversion unit is designed. 2.5kW anti-start air conditioner compressor system was implemented, and system operation and stability was verified through experiment.

• International Journal of Railway
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• v.9 no.2
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• pp.27-35
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• 2016

In spite of recent advances in ballasted railway track, the correct choice of ballast for rail track is still considered critical because aggregates progressively deteriorate under traffic loading and environmental exposures. Various ballast requirements, functions and duties have been defined by researchers, railway companies and countries' regulations even though it needs to be integrated to make following proper decision during track operation and maintenance. A proper understanding of ballast properties and suitable tests are prerequisites for minimizing maintenance costs. This paper presents a capable classification for ballast characteristics which need to be investigated beforehand to such a way, firstly to assign ballast functions, secondly need to clarify ballast requirements, thirdly to map appropriate tests to evaluate ballast characteristics and then it must be such that if ballast cannot carry out one of these duties, be able to call there is ballast defect. The paper is structured in order to achieve these objectives.

• The Transactions of the Korean Institute of Power Electronics
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• v.6 no.4
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• pp.38-38
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• 2001

The three-phase diode rectifier with capacitive filter is highly sensitive to line voltage unbalance. Because of its inherent nonlinear characteristics, small line voltage unbalance may cause highly unbalanced line current, causing detrimental effects on power quality. This paper presents a theoretical basis on this ′unbalance amplification effect′ and derives an analytical model of line current characteristics under unbalanced line voltage condition for various modes of operation. The results provide a basic guideline for optimal design of a three-phase diode rectifier with capacitive filter that is most commonly used for interfacing various power conversion equipments to power lines.

• Journal of Korea Society of Industrial Information Systems
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• v.17 no.2
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• pp.1-9
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• 2012

Wireless sensor nodes are widely used for various applications such as environmental monitoring. In this paper, the RSSI and PER are measured for the indoor environment with the various interferences such as obstacles(concrete walls, steel doors) and the 2.4GHz wireless LAN interference. Also, the RSSI and PER are measured for the outdoor environments. From the measured values of the RSSI and PER, the guideline for the stable operation of the wireless sensor network is suggested.

• Proceedings of the KSR Conference
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• 2007.05a
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• pp.1954-1961
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• 2007

This project of total city plan is developed for the area of DONGDAEGU station in the field of new city-core which is adapted for a forefront city and rational restructuring of the city space and improving for balanced growth according to the first phase operation of Korean high speed line and its complete construction to BUSAN. Bring a new heart of this city of the area of DONGDAEGU station which is a gateway to DAEGU city so that the area contrives a new creation of the city space, balanced developing and activation of a region economy. Deliberate for plan of private capital for harmonious to develop a territory of station therefore it raises an emblem of DAEGU city and activates an economy of the city according to the new trend of the condition of transportation integrated administration of a large regionand new development of DONGDAEGU station.

• Proceedings of the KSR Conference
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• 2010.06a
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• pp.2258-2261
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• 2010

Since national mid-term target for GHG reduction was determined in 2009, various efforts in transportations have been prepared. Generally, the GHG emission of transportation is calculated using the emission factor published from IPCC guideline(2006). However, it is necessary to develop new emission factors considering the properties of transportation as well as fuel. In Korean railroad, main emission sources are the consumption of diesel and electricity from railcar operation. The GHG emission of electric-powered railcars can be estimated using national electric emission factor, but diesel-powered railcars show different trends. The purpose of this study was to establish the development plans of emission factors for diesel-powered railcars. As a result, the emission factors of diesel-powered railcars were classified into railcar type, engine type and life cycle, notch, load, and traffic volume. In future, several emission factors with this category will be presented quantitatively through field tests with the order of priority.

• Proceedings of the KSR Conference
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• 2007.11a
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• pp.1254-1266
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• 2007

This project of total city plan is developed for the area of DONGDAEGU station in the field of new city-core which is adapted for a forefront city and rational restructuring of the city space and improving for balanced growth according to the first phase operation of Korean high speed line and its complete construction to BUSAN. Bring a new heart of this city of the area of DONGDAEGU station which is a gateway to DAEGU city so that the area contrives a new creation of the city space, balanced developing and activation of a region economy. Deliberate for plan of private capital for harmonious to develop a territory of station therefore it raises an emblem of DAEGU city and activates an economy of the city according to the new trend of the condition of transportation integrated administration of a large regionand new development of DONGDAEGU station.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.33 no.3
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• pp.102-113
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• 2010

In this research, we proposed a quality evaluation standard model which is suitable for the internet shopping mall based on the Malcolm Baldrige National Quality Award model. A 7-Point Likert Scale was used based on the seven categories within the 2008 Malcolm Baldrige Criteria : Leadership, Strategic Planning, Customer and Market Focus, Measurement Analysis and Knowledge Management, Workforce Focus, Process Management, and Result. Furthermore, we analysed the validity and causal relationship among the factors within the model. The goal of this research is to find a rational standard to evaluate internet shopping malls nationwide and help the structuring and the operation of these malls. The results may be used not only as a tool to evaluate internet shopping mall sites but also as a guideline to improve the quality of a internet shopping mall site that is under development.

• 한국신재생에너지학회:학술대회논문집
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• 2007.11a
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• pp.376-377
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• 2007

In accordance with Madrid and Kyoto Protocols, a 10kW wind turbine installed about 625m away from the King Sejong Station in the Antarctica has been in operation successfully. The current location of the wind turbine has different geographic surroundings from the previous candidate site considered in 2005 and that makes re-evaluation of wind resource at the current site including geographic effects necessary. Especially, strong wind flow derived by steep and complex terrain is dominant in the Antarctica so that computational flow analysis is required. The wind rose measured at the previous and current installation location are identical with strong meteorological correlation but prevailing directions of wind power density are different because of local wind acceleration due to complex terrain. Numerical analysis explains which effects brings this discordance between the two sites, and a design guideline required for additional wind turbine installation has been secured.