• Proceedings of the Korean Society of Marine Engineers Conference
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• 2011.06a
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• pp.192-192
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• 2011

For the safety of vessels sailing Marine Transport Facility announces sea route, reefs or shallow water. Photovoltaic, independent power system, installation in the general Marine Transport Facilities to be used in the marine lantern. Due to install of communications, controls, power consumption inceases. And the weather of cloudy day or rainy, generation of electricity is decrease. Recently, power system of marine facility using a hybrid generation system, photovoltaic generation system and wave power generation system. But increase of adhered shellfish inside the water column, is the cause of the reduction of efficiency. So study was conducted to Single channel AFS(Anti-Fouling system). In this paper we offer the Multi channel AFS for Marine Transport Facility and have simulated. Improve the accuracy of the research, we using the result of anode, in the experiment were actually in the buoy, is based on simulation. The experimental results is shown every anode's, in the Marine Transport Facility, ionization was conducted identically.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.29 no.4
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• pp.85-94
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• 2015

Recently, research on the smart grid that combines ICT(Information & Communication technology) to the power system has been actively progressed. If the occupancy of the EV(Electric vehicle) is increased. the V2G(Vehicle to grid) system is available which constitutes the micro-grid through battery of EV. V2G system performs load leveling and efficient energy consumption by battery operation considering load condition. But, if the battery is used only depending on the electricity rates, it doses not consider the life of the battery. The ACC(Achievable cycle) and the total transferable energy of battery varies corresponding to the selected DOD(Depth of discharge). In this paper, the optimal DOD selection method of V2G system considering battery wear cost and average driving distance of EV. Also, the total revenue prediction of various nation is presented considering the actual electricity costs per hour.

• Proceedings of the SAREK Conference
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• 2009.06a
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• pp.934-939
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• 2009

To promote citizen's involvement in the GHG(Green House Gas) reduction policy, Busan city administration adopted an pilot energy incentive system called 'energy mileage'. The energy mileage system was designed to make energy end-users motivated to reduce domestic electricity use by providing financial rewards. Through the course of the pilot period, 5,3330 householders volunteerly participated the pilot system. About 66% of the participants managed to make energy saving against the same period of the previous year while 38.8% achieved the targeted reduction rate(i.e. over 10%) and received the equivalent rewards.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.8
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• pp.1795-1801
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• 2009

In this study, a portable flashlight which can manually generate the electricity by using sunlight was developed so that it can be used in the extreme environmental condition such as no-electricity condition. Battery is charged by using solar battery during the day, but when sunlight is not avalible during the night or rainy day, a handle is rotated to generate the electricity in order to charge the battery manually. To improve the brightness of the light, light is concentrated by using the optical lens. Low electric consumption circuit is used for the longer operating time by suppress electrical consumption while lamp is discharged. A circuit is designed and used for steady electrical curris dand voltage to insure steady battery charging. Super-discharge circuit and protection circuit are used for the super discharge of battery when it is not used for a long time. Also the constant charge is possible by using houseware adapter. As a result, a portable flashlight is designed to charge with sunlight during day, and with houseware adapter during night. A portable flashlight is also designed to irradiate longer distances by improvement of the brightness of the light using the optical lens. Thus, it forms white natural ray of light making possible for night reading.

• Journal of Hydrogen and New Energy
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• v.34 no.2
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• pp.187-195
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• 2023

Data centers not only consume significant electricity to operate IT equipment, but also use a lot of electricity to cool the heat generated by IT equipment. The waste heat of a high-temperature polymer electrolyte fuel cell (HT-PEFC) is capable of producing cooling , so it can be effectively applied to data centers that require cooling throughout the year. The energy-saving effects of the proposed combined cooling, heat and power (CCHP) system using HT-PEFC. That was analyzed based on the annual energy consumption data of a specific data center. When the system was running at 100% of the year, It was shown that the installation of 1 MW of the proposed system can save 3,407 MWh of electrical energy per year. In addition, compared to the existing system, the annual power usage effectiveness can be improved from 2.0 to 1.57 and 6,293 MWh of extra heat energy per year can be produced to sell. Furthermore, sensitivity analysis was performed on the fuel cell operating temperature and current density to guide the appropriate installation capacity of the proposed system.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.11
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• pp.5879-5884
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• 2013

With the rapid industrialization and economical development, the electricity demands of the industrial facilities and densely populated large cities are continuing to increase in Korea. The increase in the power consumption requires the extension of power facilities, but it is difficult to secure spaces for equipment installation in the limited space of urban areas. In addition, the 154 kV or 345 kV transmission systems in Korea has a short transmission distance, and are connected to one another in network structures that ensure the high reliability and stability of power supply. This structure reduces the impedance during the fault in power system, and increases the magnitude of in the short circuit fault current. The superconducting fault current limiter (SFCL) was devised to effectively address these existing problems. The SFCL is a new-concept eco-friendly protective device that ensures fast operation and recovery time for the fault current and does not need additional fault detection devices. Therefore, many studies are being conducted around the world. In this paper, based on the wiring method the initial fault current characteristics, current limiting characteristics, according to the incident angle and the change in inductance current limiting characteristics were analyzed in a multifaceted methods.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.29 no.11
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• pp.612-620
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• 2017

Power consumption in Southeast Asia is steadily increasing due to industrialization and the effects of hot and humid climates. However, there are not enough energy generation facilities and infrastructures to meet the growing demand because it is difficult to secure the construction and operation costs of the transmission and distribution systems. This study aims to develop a gas engine driven heat pump system that supplies heating, cooling and electric power to buildings. This system, besides its normal function to produce heat, has the capacity to generate electricity on a household level. This paper investigates similar cases overseas before developing the system. Through the investigation of commercialized similar systems, the level of technology and market trend of development system were identified. Features and specifications of commercial and industrial systems will be used for system development.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.65 no.1
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• pp.16-22
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• 2016

This paper addresses the load usage scheduling in the HEMS for residential power consumers. The HEMS would lead the residential users to change their power usage, so as to minimize the cost in response to external information such as a time-varying electricity price, the outside temperature. However, there may be a consumer's inconvenience in the change of the power usage. In order to improve this, it is required to understand the pattern of load usage according to the external information. Therefore, this paper suggests a methodology to model the load usage pattern, which classifies home appliances according to external information affecting the load usage and models the usage pattern for each appliance based on a copula function representing the correlation between variables. The modeled pattern would be reflected as a constraint condition for an optimal load usage scheduling problem in HEMS. To explain an application of the methodology, a case study is performed on an electrical water heater (EWH) and an optimal load usage scheduling for EHW is performed based on the branch-and-bound method. From the case study, it is shown that the load usage pattern can contribute to an efficient power consumption.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.65 no.5
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• pp.878-882
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• 2016

These days, SFCLs are being developed in order to limit fault current. However, the superconducting elements that limit the fault current have such problems as capacity increase and require auxiliary devices including cooling device. If devices that comprise the current power network can withstand fault current for at least one cycle, it is possible to limit the fault current with current limiting elements by bypassing it on the fault line. In this study, the fault current limiter was configured with current transformer, vacuum interrupter, and current limiting element. Through the experience, it was confirmed that the fault current was limited within one cycle. The superconducting element, as a current limiting element, limited the fault current by 80 % within one cycle from fault occurrence, and the passive element limited it more than 95 %. Also, through the comparison between resistance curve and power consumption curve, it was confirmed that the current limiting element using a passive element was more stable than the superconducting element that required capacity increase and other auxiliary devices. It was considered that the FCL proposed in this study could limit fault current stably within one cycle from fault occurrence by using the existing power technologies such as fault current detection and solenoid valve operating circuit.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.28 no.6
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• pp.113-121
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• 2014

At the end of the 19th century, a battle known as the War of the Currents was fought over how electricity would be generated, delivered, and utilized. In this day and age, there has been a growing interest in Green Growth policies as countermeasures against global warming. As a result of these policies, the use of new and renewable energy needed a power converter to replace fossil fuels has expanded. To reduce power consumption through high efficiency of conversion, Low Voltage DC (LVDC) distribution systems are suggested as an alternative. In a DC distribution system, DC loads are very efficient due to decrease the stages of power conversion. If the LVDC distribution system is adopted, not only DC load but also existing AC loads should be connected with LVDC system. Thus, the modeling of two loads is needed to analyze the DC distribution system. This paper, especially, is focused on the modeling of resistive load and electronic load including power electronic converters using ElectroMagnetic Transient Program (EMTP) software.