• Journal of the Korea Concrete Institute
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• v.19 no.4
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• pp.475-482
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• 2007

The property and applicability of the organic-inorganic synthesized penetrating and reinforcing agent, which is developed in order to improve durability of concrete structures and prevent deterioration that may occur as service years increased, are researched with experimental works. TEOS (tetra-ethoxyorthosilicate) and acrylate monomer are synthesized by the solution polycondensation method in order to formulate silicate with sol-gel process and improve durability of concrete. Additional substances such as isobutyl-orthosilicate is supplemented in order to improve the performance of the agent. After the developed organic-inorganic penetrating reinforcing agent penetrates, a flexible impact alleviating layer is formed with organic monomers as well as the agent strengthens concrete by filling up the internal pore of concrete with stable compounds after penetration. Penetrating and reinforcing agent can be applied as an effective life management method because it makes concrete more durable against the aging factors, such as chloride ion, carbonation, freezing-thawing, and compound aging.

• Proceedings of the KSR Conference
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• 1999.11a
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• pp.267-272
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• 1999

The auxiliary power supply system fur passenger service of railway car has been developed from MA(Motor-Alternator) to CVCF Inverter (Static Inverter). Generally, a customer wants to apply tile new control method and device for auxiliary power supply of railcar However, if the auxiliary power supply is supplied to extended existing line, the maintenance cost of the old system is less expensive than new developed system, so, the customer specifies that the auxiliary power supply has compatibility with existing one completely. At that time, the hardware is nearly same as existing system except small changes of accessories for better performance. This paper describes the flicker control using feed-forward method of auxiliary power supply system for new 50 electric railcars, which are delivered to Korean National Railroad (KNR) Kwa-chon Line. The existing power supply system has damping resistor box to stabilize the DC input (1.5 ㎸). At this time, for better system efficiency the new system has not include resistor box but new control method including feed-forward control is applied. This control algorithm realizes the better stabilization of input power compared to the result of the existing system, which includes resistor box

• The Journal of the Korea institute of electronic communication sciences
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• v.11 no.8
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• pp.773-782
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• 2016

Recently, Energy Industry is in the face of such sustained Low-Growth, Energy Depletion, Climate Warming and Energy Companies bankruptcy, Various methods have been tried to break through it. In this paper, We propose Business Model of Energy New Industry in Electric Power Market after analyze background of Energy New Industry and Technology Trends. The proposed Business Model introduces Energy of Things(: EoT) Service based Advanced Metering Infrastructure, Energy Storage System(: ESS) for Frequency Regulation, Energy Prosumer using Vehicle and Grid(: VnG) and Smart City.

• Proceedings of the KIEE Conference
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• 2008.11a
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• pp.376-378
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• 2008

This paper covers that modem performance test is effected by traffic and analysis of the result in TETRA network. The SDS is a method of the between PEIs transmission. And only SDS message type-4 is used to test. The range of the SDS message data length is from 10 to 140 bytes with an increment of 10 bytes. For each length transmitted 1000 times for each delay of inter-transmissions 0.5 second, 1.0 second and 1.5 second. The modem used in the test is the Unimo MU-1000MD by UNIMO Corp.

• Proceedings of the KIEE Conference
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• 1999.07c
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• pp.1101-1103
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• 1999

Deregulation and restructuring of electric industry change the fundamental nature of electric business which will be coordinated by the evolved market structures such as spot market with pool and bilateral transaction structure, forward market and future market. Introduction of competition can significantly change the system operation in near-terms as well as long-run generation expansion planning Previous centralized planning by monopoly utilities which was guided for the public service purpose will be replaced by decentralized investments plan by individual generation companies in response to commercial incentives. This paper reviews WASP model as a centralized planning tool and presents a methodological analysis of generation expansion planning in deregulated power systems. It stresses how affects the process of planning new generation investments by the introduction of competition and how maintains proper fuel mix and continuously sustains system reliability under deregulated environments.

• Journal of Electrical Engineering and Technology
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• v.5 no.4
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• pp.530-537
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• 2010

By development of renewable energy and more efficient facilities in an increasingly deregulated electricity market, the operation cost of distributed generation (DG) is becoming more competitive. International environmental regulations of the leaking carbon become effective to reinforce global efforts for a low-carbon paradigm. Through increased DG, operators of DG are able to supply electric power to customers who are connected directly to DG as well as loads that are connected to entire network. In this situation, a community energy system (CES) with DGs is a new participant in the energy market. DG's purchase price from the market is different from the DG's sales price to the market due to transmission service charges and other costs. Therefore, CES who owns DGs has to control the produced electric power per hourly period in order to maximize profit. Considering the international environment regulations, CE will be an important element to decide the marginal cost of generators as well as the classified fuel unit cost and unit's efficiency. This paper introduces the optimal operation of CES's DG connected to the distribution network considering CE. The purpose of optimization is to maximize the profit of CES. A Particle Swarm Optimization (PSO) will be used to solve this complicated problem. The optimal operation of DG represented in this paper would guide CES and system operators in determining the decision making criteria.

• The Transactions of the Korean Institute of Power Electronics
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• v.24 no.3
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• pp.139-146
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• 2019

As the number of electric vehicles (EVs) in Jejudo Island increases, the secondary use of EV batteries is becoming increasingly mandatory not only in reducing greenhouse gas emissions but also in promoting resource conservation. For the secondary use of EV batteries, their capacity and performance at the end of automotive service should be evaluated properly. In this study, the battery state information from the on-board diagnostics or OBD2 port was acquired in real time while driving three distinct routes in Jejudo Island, and then the battery operating characteristics were assessed with the driving routes. The route with higher altitude led to higher current output, i.e., higher C-rate, which would reportedly deteriorate state of health (SOH) faster. In addition, the SOH obtained from the battery management system (BMS) of a 2017 Kia Soul EV with a mileage of 55,000 km was 100.2%, which was unexpectedly high. This finding was confirmed by the SOH estimation based on the ratio of the current integral to the change in state of charge. The SOH larger than 100% can be attributed to the rated capacity that was lower than the nominal capacity in EV application. Therefore, considering the driving environment and understanding the SOH estimation process will be beneficial and necessary in evaluating the capacity and performance of retired batteries for post-vehicle applications.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.53 no.9
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• pp.521-528
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• 2004

The demise of the native franchise markets and the emergence of competitive markets in electricity generation service is substantially altering the way that operation and planning activity is conducted and is making it increasingly difficult for market participants such as generation firms to prospect the future electricity markets. Traditional generation expansion planning (GEP) problems which centrally determine the least-cost capacity addition plan that meets forecasted demand within pre-specified reliability criteria over a planning horizon (typically 10 to 20 years) is becoming no more valid in competitive market environments. Therefore, it requires to develop a new methodology for generation investments, which is applicable to the changed electric industry business environments and is able to address the post-privatization situation where individual generation firms seek to maximize their return on generation investments against uncertain market revenues. This paper formulates a new generation expansion planning problem and solve it in a market-oriented manner.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2001.11a
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• pp.203-206
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• 2001

Since th three sides of korea peninsula are surrounded by the sea, electric apparatus are greatly contaminated by the salt generated by the typhoon, seasonal wind, sea wind and sea fog. This contamination causes electric power apparatus to fail. Thus in this paper, we investigated to influence upon electrical properties of outdoor insulators with non-uniformity contamination in the experimental condition because The contamination of outdoor insulator highly depended wind property In the service condition, insulator was not uniformly contaminated. From the flashover test for the 254 mm suspension insulator, we could determine the influence non-uniform contamination on the electrical property of insulators. Through the experiment, we convinced to occur flashover from non-uniform contamination region of outdoor insulator. Contaminated area and pattern has a close relationship with the electrical properties of outdoor insulator.

• Transactions of the KSME C: Technology and Education
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• v.4 no.1
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• pp.57-62
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• 2016

The Demand Response Market is a nation-wide power and energy management program of electric power demand response operated by KPX (Korea Power eXchange). Therefore, any savings could be determined by KEPCO's AMR(Automatic Meter Reading) data. However, the customers and the service providers participating in the market could not know the real time value due to the 15 minute or even more delayed AMR data communicated. Here, a new concept of a smart box has been introduced and demonstrated to provide the real time saving values compared to the current KEPCO's AMR data approach.