• Journal of the korean Society of Automotive Engineers
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• v.15 no.1
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• pp.55-66
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• 1993

The characteristics of the flow processes in the cylinder of the two-stroke cycle engines have become the subject of increasing and attention owing to the simplicity and the higher power per unit weight of the two-stroke cycle engine. Among the many factors which influence on the scavenging flow, the port angle is important factor. Hence, four different type models with one inlet-port and two side-ports are studied to show the effect of port angle on the laminar scavenging flow. When the inlet-port axial is relatively larger than the side-port axial angle, it is showed that the fresh charge penetrate into the burned gas and displace it first toward the cylinder head and then toward the exhaust port. When the inlet-port axial angle is much less than the side-port axial angle, the fresh charge through the inlet-port directly move toward the exhaust port. The result showed that the model A may suppress the generation of vortices in the vicinity of inlet and side prots which restrict the sufficient supply of fresh charge and obstruct the perfect displacement of all combustion products.

• 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 Ocean Engineering and Technology
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• v.31 no.4
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• pp.266-273
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• 2017

In recent years, LNG bunkering terminals are needed to supply LNG as fuel to meet the emission requirements of the International Maritime Organization (IMO). A floating LNG bunkering terminal (FLBT) is one of the most cost-effective and environmentally friendly LNG bunkering systems for storing LNG and transferring it directly to an LNG fuel vessel. The FLBT maintains its position using mooring systems such as spread mooring and turret mooring. The loads on the vessel and mooring lines must be carefully determined to maintain their positions within the operable area. In this study, the wind loads acting in several side-by-side arrangements on the FLBT and LNG-BS were estimated using wind tunnel tests in the Force Technology, and the shielding effect due to the presence of ships upstream was evaluated. In addition, the empirical formulations proposed by Fujiwara et al. (2012) were used to estimate the wind force coefficients acting on the FLBT and those results were compared with experimental results.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.60 no.6
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• pp.1103-1111
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• 2011

This paper is developed to Energy Balance Flow show the flow of total energy resource be used nationally. The Energy Balance Flow is applicable of demand management factor through the analysis of foreign energy model of supply and demand and energy statistic data in the country. This study is based on and developed to Energy system management model is able to appraisal efficient of energy cost cutting, CO2 emission reduction and Energy saving at the national level calculated effect reached amount of primary energy to change of energy flow followed application of demand side management factor is able to appraisal quantitatively at the total energy to model of demand and supply.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.29 no.3
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• pp.1-7
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• 2015

Korea's electricity supply and demand policy has focusing on electricity demand side management instead of the expanding supply and a lot of effort for LED(Light Emitting Diode) at the time. This paper calculated the optimal subsidy for LED spread. For this purpose, it analyzed the impact on spread of the lighting appliances each subsidy level from BDM(Bass Diffusion Model) and predicted the number of lighting appliances according to subsidy level in the future. The case study is calculated susidy for satisfaction of LED target using the suggested model in the future and verified availability.

• Proceedings of the KIEE Conference
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• 2011.07a
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• pp.679-680
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• 2011

This paper is developed to Energy Balance Flow show the flow of total energy resource be used nationally. The Energy Balance Flow is applicable of demand management factor through the analysis of foreign energy model of supply and demand and energy statistic data in the country. This study is based on and developed to Energy system management model is able to appraisal efficient of energy cost cutting, CO2 emission reduction and Energy saving at the national level calculated effect reached amount of primary energy to change of energy flow followed application of demand side management factor is able to appraisal quantitatively at the total energy to model of demand and supply.

• The Transactions of the Korean Institute of Power Electronics
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• v.11 no.2
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• pp.120-126
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• 2006

A gate driver with Boot-strap chain is proposed to drive Multi-level PDP sustain switches. The proposed gate driver uses only one boot-strap capacitor and one diode per each MOSFETs switch without floating power supply. By adoption of this gate driver circuits, the size, weight and the cost of the driver board can be reduced.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.65 no.4
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• pp.303-308
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• 2016

A light-emitting diode (LED) has been increasingly applied to various industrial fields and general lightings because of its high efficiency, low power consumption, environment-friendly characteristic and long lifetime. To drive this LED lighting, various types of power converters have been applied. Also, power factor correction (PFC) techniques play an important role in the power supply technology. In this paper, design and control of a DCM interleaved boost PFC converter is discussed. The proposed converter can reduce current ripples at input and output side by cancelling an each phase of inductor currents. Since the IC does not require the auxiliary winding of inductor for current detection, simple PFC circuit is achieved. Therefore, it contributes to increase efficiency and downsize the whole system volume, cost. Also, the performance of the proposed system is demonstrated through experiments.

• Proceedings of the KIEE Conference
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• 2005.07a
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• pp.736-738
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• 2005

For calculating optimal generation composition of The Basic Plan of Long Term Electricity Supply & Demand, the Screening Curve Method that using generation cost for planning is needed. This paper will induce optimal power system ratio included Combined Head and Power and suggest the method for optimal generation composition of The Basic Plan of Long Term Electricity Supply & Demand that considered policy side.

• Management & Information Systems Review
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• v.13
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• pp.141-162
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• 2003

This article discusses the issues of the estimated size and characteristics of irregular employment work force in Korea after IMF economic crisis in 1997. The issues of the estimated size of irregular employment work force originated from different concepts and its operationalizations among the labor economists, despite their utilization of the same labor force data, 'Economically Active Population Survey(EAPA)' collected from Korea National Statistical Office(KNSO). And the issues contribute toward the understandings of the irregular employment and the limits of the EAPA, despite its various usefulness. This article also describes the summary characteristics of irregular employment work force from both sides of labor supply and its demand. The major characteristics of irregular employment work force on the labor supply side appears in the concentration of social minorities, i.e. woman, the aged, lower educated and skilled populations. On the labor demand of irregular employment work force, the majority of it concentrated on the establishments under 10 employees, and probably the important incentives for irregular employment work force of the firms is labor cost efficiency. Finally, this article propose an alternative against the discrimination between the regular and irregular work force.