• Proceedings of the KIEE Conference
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• 2006.04a
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• pp.198-200
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• 2006

In this paper, three types of power control strategies for controlling a Fuel Cell Hybrid Electric Vehicle(FCHEV) are studied in view of fuel economy. The FCHEV has become one of alternatives for future vehicles since it does emit water only without any exhaust gas while it has a high well-to-wheel efficiency together with an energy saving due to regenerative braking. However, it has also several disadvantages such as the complexity of vehicle system, the increased weight and the extra battery cost. Among various power control strategies, a static power control strategy, a power assist control strategy and a fuzzy logic-based power control strategy are simulated and compared to show the effectiveness of each method.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2000.11a
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• pp.135-143
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• 2000

This parer is the among educational environment, lighting's role is more important since it improves the visual tasks, capability of work, and it help to build both balanced mind and body. Also, since students need spend most of their time inside rather than outside, students need appropriate illuminance everyday. If optimum illuminance and distribution of luminance is properties controlled, people can decrease the fatigue of eyes, and also, people can maximize their efficiency of work. This present studying class chose of two school measured illuminance using the computer simulation improved ratio of luminance and luminance by distribution of lighting improve the economy and energy saving.

• Proceedings of the KIPE Conference
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• 2003.11a
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• pp.77-80
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• 2003

As rapid growth of energy demand in line with modern society's industrialization led to environmental pollution by fossil fuels, there are more and more interest and international research on energization of water, which is clean energy and comprising $70\%$ of earth. In offshore countries, the water is commercially used already and water has very attractive characteristics in terms of economy and efficiency compared to the existing gas welder. Brown Gas welder does not produce $CO_2$ from combustion of Hydrogen-Oxygen-Gas, which was gained by electrolysis of water, In this paper, the result from operating characteristic improvement of Gas Generator and Current-Controlled converter is to be considered into design in electrode, source/ controller, standized into level of whole system design base.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.50 no.7
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• pp.329-333
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• 2001

The pulsed poser system has been widely used to many applications, such as E/P(Electrostatic Precipitator), DeNox/DeSOx power system, ozon generator, etc. A pulse energy efficiency for load depends on the rising time, peak value, pulse duration and impedance matching, etc. The pulse generator generally required for short pusle duration and high peak value was forced to consider its volume and economy. In this study, developing a compact pulse generator that applied for cascading method to be made of two pulse transformers, we compared cascading voltage with non cascading one by applying the pulse energy to load. Adopting cascading technique to pulse transformer, we found that average cascading voltage was about 60[%] of theoretical value. Maximum cascading ratio was calculated at 60 times compared with non cascading voltage.

• Proceedings of the KIEE Conference
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• 2002.11b
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• pp.47-49
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• 2002

Recently, the power system has a trend of a sustaining growth in electric power demand with large-sized formation. In this situation, current states can be definitely comprehended to operate security and economic power system. Also, corrective actions must be performed for the violation of bus voltage and line overload. In the security and economy with on-line, It is desirable that the situations of violation are promptly removed to operate power system effectively. This paper deals with the development of application, Kangyang Steel Works' Power System Guidance System, for voltage and overload correction on base case using Generator-Voltage Sensitivity List(GVSL) and Generator Shifter Factor List(GSFL). Also, to show the superiority and economical efficiency of the proposed application, we simulate the Kangyang Steel Works' Power System.

• Proceedings of the KIEE Conference
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• 2002.07c
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• pp.1800-1803
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• 2002

The pulsed power system was widely making use good of many industrial and environments. The pulse generator generally required for short pulse duration and high peak value was forced to consider its volume and economy. In this paper, this system is designed and fabricated which has a compact size of pulse generator with switched MOSFET. We have studied the removal of rust material using Arc discharging in pulsed power system. It have tested their characteristics by adjusting variable voltage charging and pulse repetition rate. As a result, We can eliminate rust materials with this device.

• Environmental and Resource Economics Review
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• v.10 no.4
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• pp.569-589
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• 2001

We examine historical contributions of inter fuel substitution, changes in carbon efficiency and energy intensity, growth of economy and population to Korea's $CO_2$ emissions from 1970 to 1998 using the log mean weight Divisia index method. The study reveals that economic growth is the most significant factor to $CO_2$ emissions growth among the five factors. Changes in the fuel substitution and carbon coefficient are found negative contributors to $CO_2$ emissions growth. Energy intensity, which played dominant role in halting $CO_2$ emissions growth in the 1980s, began to play reversed role in the 1990s. When evaluated with the log mean Divisia index technique, deterioration of energy intensity in the 1990s is found worse and expected to contribute $CO_2$ emissions growth further.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.20 no.2
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• pp.202-206
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• 2011

Works on the strength and stiffness in the structural members are carried out widely with various material and cross-sections with ever increasing safety concerns, they are presently applied in various fields including railroad trains, air crafts and automobiles. In addition to this, problem of lighting structural members became important subject by control of exhaust gas emission, fuel economy and energy efficiency. So, Light weight of member structures is necessary for the high performance and various functions. In this study, the CFRP flat and circular member was manufactured by CFRP prepreg sheet in autoclave. Carbon FRP is an anisotropy material whose mechanical properties change with its fiber orientation angle, so this study apply to the effects of the fiber orientation angle on the bending characteristics of the member. Each CFRP flat and circle are compared by strength and stiffness.

• Water Engineering Research
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• v.3 no.1
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• pp.1-8
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• 2002

Cloud seeding has not been used now to regulate water supplies in Korea and this results in losses to economy. The fastest experiments on precipitation enhancement in the world show that there are real possibilities to increase precipitation by 10-20%. Investigations of economic losses due to the lack of routine cloud seeding experiments in Korea have shown that they exceed about 100 million US dollars In 1999. Recommendations on cloud seeding activities including works on precipitation augmentation and prevention of heavy rains are presented. Spatial and temporal necessity to carry out this or that work is discussed.

• Transactions of the Korean Society of Automotive Engineers
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• v.8 no.1
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• pp.63-71
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• 2000

A shift control algorithm of a newly developed two-speed gear shift system is proposed for electric vehicle applications. The algorithm is formulated according to the motor torque map and optimized to obtain the adequate propulsion characteristics for vehicle. Two speed gear system with shift control algorithm has proved greater efficiencies in terms of energy economy with its simplified hardware and software structures. The gear shifting is designed to be carried out by an actuator and the control signal from a vehicle control unit equipped with $\mu$-processor. The results of performances and efficiency of the algorithm by simulation and vehicle test are described.