• Journal of Electrical Engineering and Technology
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• v.11 no.3
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• pp.629-638
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• 2016

This paper proposes a State-of-Charge (SOC) balancing control of Battery Power Modules (BPMs) for a modularized battery for Electric Vehicles (EVs) without additional balancing circuits. The BPMs are substituted with the single converter in EVs located between the battery and the inverter. The BPM is composed of a two-phase interleaved boost converter with battery modules. The discharge current of each battery module can be controlled individually by using the BPM to achieve a balanced state as well as increased utilization of the battery capacity. Also, an SOC balancing method is proposed to reduce the equalization time, which satisfies the regulation of a constant DC-link voltage and a demand of the output power. The proposed system and the SOC balancing method are verified through simulation and experiment.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.6 no.2
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• pp.129-133
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• 2005

It is very important to use the charge coupled devices (CCDs) in spectrometry because we can study the molecular energy level, molecular structure, absorption or emission, intermolecular reaction, weakly bound molecular energy, photochemistry, fluorescence and photodynamic therapy (PDT). CCD is very essential to study the molecular structure and medical engineering combining laser spectroscopy in the modem physicsal and chemistry. Therefore, this study has designed and manufactured the electromagnetic spectrometry with CCD and then analyzed the printed electronic circuit. In the yesterday, CCD was thought to be used in only broadcasting system. But nowadays, it is used by industrial demand in observations, instrumentations and robotics as the industry develop.

• Proceedings of the KIEE Conference
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• 1999.11d
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• pp.968-970
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• 1999

The trend of increasing of portable electric devices and demand for global environmental conservation have demands the development of high energy density rechargeable batteries. Lithium polymer battery has excellent theoretical energy density and energy conversion efficiency. Lithium polymer battery, included solid polymer electrolyte(SPE), can be viewed as a system suitable for wide applications from thin film batteries for microelectronics to electric vehicle batteries. The purpose of this paper is to research and development of flyash anode for lithium polymer battery. We investigated AC impedance response and charge/discharge characteristics of flyash/SPE/Li cells. The radius of semicircle associated with the interfacial resistance of flyash/SPE/Li cell increased very slowly during discharge process from 3.11V to 0.478V. And then the cell resistance was decreased at discharge process from 10% SOC to 0% SOC. Also, The radius of semicircle associated with the interfacial resistance of flyash/SPE/Li cell decreasing very slowly during charge process. And then the cell resistance was increased after 20th discharge precess. The discharge capacity based on flyash of 1st and 20th cycles was 276mAh/g and 143mAh/g.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.28 no.9
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• pp.20-27
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• 2014

The power consumption pattern of high-speed railway has rarely during night time. But, during service time, the power is consumed irregularly related to train operation. Especially certain unusual about 1-2 days of service time interval to indicate the power consumption is rapidly growing phenomenon, which causes the capacity of the power contract is the annual electricity bill to rise rapidly as the cause. Normally, amount of peak power consumption bill rate at railway substation is over 20% of total electrical bill. Therefore, high-speed railway substation is expected to be considerably larger savings by reducing the peak power of the default charge(demand power).

• Proceedings of the KIEE Conference
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• 2000.07a
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• pp.376-378
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• 2000

The current worldwide electricity market introduced competition, which is breaking up the monopoly structure and also enforcing phased structural reform in South Korea. The change of the electricity charge from cost base to price base due to the introduction of the electricity market competition causes consumer to choose a variety of charge schemes and a portion of loads to be affected by this change. Therefore, in order to find a mathematical model of the sensitively-responding-to-price loads and reflect this to the DSM demand management, the price-sensitive load model is needed. Thus, this paper first proposes the composite price-sensitive load model that is expressed as a function of price, presents the methodology to estimate price-sensitive load model at each bus by bus load compositions.

• The Journal of the Korea institute of electronic communication sciences
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• v.8 no.10
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• pp.1499-1504
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• 2013

As oil price and demand for environment friendly vehicle rapidly increase, research on electric car is being widely carried out. Especially, NEV(Neighborhood Electric Vehicle) is a pollution-free vehicle that can be mass-produced which the time of development for related technologies is urgently needed. In this paper the On-Board charger for mid- and large- sized secondary cell is applicable in aerospace and other general industries, and the Off-Board standing charger is expected to be employed in creating charging infrastructure.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.25 no.9B
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• pp.1618-1634
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• 2000

ISDN, the beginning of broadband and multimedia service, is a digital network that provides integrated end-to-end digital telecommunication services for transmissions of different kinds of information, from voice and facsimiles to data and images. In Japan, Britain and U. S there has been shown the demand of ISDN is considerable and ISDN technology is becoming quite stable. Furthermore,their ISDN service experience helps them to set up and carry out the marketing strategies for Internet access services such as ADSL, Cable Modem and WLL, etc. This paper examines and compares services, charge and discount scheme of ISDN across 14 telecommunication carriers. It can be utilize as a reference for diffusing ISDN as well as developing Internet access services and marketing strategies.

• Journal of the Korea Safety Management & Science
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• v.17 no.3
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• pp.331-341
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• 2015

Gasoline prices vary across Korea. Some gas stations charge higher prices, while others charge lower prices. In this paper, we try to find: why gasoline prices differ markedly across regions. We empirically estimate the determinants of gas prices by incorporating supply side factors as well as demand side factors into the empirical model. Empirical results show that both location-specific factors and store-specific factors affect gas prices. Concentration of competing stores, store brands, ownership of gas stations, and self-service availability influence gas prices. In addition, the availability of other customer services such as convenience stores, car wash, and auto repairs affects gas prices.

• Proceedings of the Korean System Dynamics Society
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• 2007.06a
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• pp.113-129
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• 2007

Due to criminal aspects spreading nation wide, their intelligence level increasing and becoming digitalized, the citizens' interest in and desire for crime security have increased. Until now, the preceding researches have been focused on finding the specific variables that have direct effects on the demand for police manpower through regression analysis and attempted to predict number of needs. However, there have never been any researches producing the accurate number of demands for crimes and human resources needed for each work load. Therefore, this research have analyzed each police station functions by interviewing the persons in charge and selected the main duty for each functions. From this, by using the method of system dynamics, this research was able to predict the standard number of manpower needed for each police station functions. Also, by making a model for each 235 police stations, the best efficient employment plan for police stations and district agencies have been further discussed based on the computer simulation results.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.20 no.44
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• pp.61-68
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• 1997

The algorithm of customer demand decomposition suggested by this study is a reconstruction method of distribution network under the allowance of same level supply. Regional distribution center(RDC) distributes additional inventories of some of the supplying items to retailers under its charge to reduce the time needed for emergency delivery to neighborhood retailer where backlog happened. This also restrict the purpose of the inventories held by RDC as only regular supply. All of which leads to the creation of more realistic method allowing the affiliation of closing related RDC with one in the vicinity. In this study, the role of RDC is restricted only as supplying items regularity and the conruction of distribution system processing through the closing by consideration of the possibility of supplying retailers from the RDC in the vicinity is discussed.