• Asia pacific journal of information systems
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• v.31 no.3
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• pp.257-276
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• 2021

This study investigates the factors that facilitate or hinder people to use mobile payment, especially drawing upon the theoretical perspectives on individual's privacy protection motivation and perceived market condition. Survey data (n = 200) were collected through a web-based platform and used to test a theoretical model. The results show that one's privacy protection power is formed by various individual and technological factors (i.e., perceived data exposure, self-efficacy, and response efficacy), and in turn it determines his/her intention to use mobile payment. Moreover, the relationship between privacy protection power and mobile payment use is conditional on the perceived market control by the service provider - with a perception of the high level of provider's market control, one uses mobile payment regardless of his/her privacy protection power, while under the low level of provider's market control, the decision depends on the degree of privacy protection power. The findings would help our understanding of why some people are more susceptible to mobile payment and others are not.

• Proceedings of the KIEE Conference
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• 1998.11a
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• pp.256-258
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• 1998

This paper presents a control system design for the UPFC of FACTS devices by optimal control scheme to enhance small-signal stability in the Power system. The feature of this UPFC controller is coordinated with generator exciter controller(AVR, PSS) to improve the total Power system stability and performance.

• Proceedings of the KIPE Conference
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• 2001.10a
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• pp.571-575
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• 2001

A protection scheme for hybrid active power filters, which is combined shunt passive filter and small rated series active filter, is presented and analyzed in this paper. The proposed series active power filter operated as a high impedance 'k($\Omega$)' to the fundamental component when over current occurs in the power distribution system, and three control strategies are proposed in this paper. The first is the method by detecting the fundamental source current through the p-q theory, the second is the method by detecting the fundamental component of load current in Synchronous Reference Frame (SRF) and the third is the method by detecting the input voltage. When the over current occurs in the power distribution system, the proposed scheme protects the series active power filter without additional protection circuits. The validity of proposed protection scheme is investigated through experimental result for the prototype hybrid active power filter system.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.49 no.6
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• pp.280-288
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• 2000

Recently, there has been growing interest in utilizing cogeneration(COGN) systems with a high-energy efficiency due to the increasing energy consumption and the lacking of energy resource. But an insertion of COGN system to existing power distribution system can cause several problems such as voltage variations, harmonics, protective coordination, increasing fault current etc, because of reverse power of COGN, especially in protective coordination. A study on a proper coordination with existing one is being required. The existing power distribution system is operated with radial type by one source and protection system is composed based on unidirectional power source. But an Insertion of COGN system to power distribution system change existing unidirectional power source system to bidirectional power source. Therefore, investigation to cover whole field of power distribution system must be accomplished such as changing of protection devices rating by increasing fault current, reevaluation of protective coordination. In this paper, simulation using PSCAD/EMTDC was accomplished to analyze effect of COGIN on distribution fault current. Also, the existing protection system of 22.9[kV] power distribution system and customers protection system to protect of COGIN was analyzed and the study on protective coordination between of two protection system accomplished.

• Journal of Electrical Engineering and Technology
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• v.13 no.6
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• pp.2196-2202
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• 2018

The conventional power system allowed only downstream power flow. Therefore, even if a fault occurs, only the forward current flow is considered. However, with the interest in distributed generation (DG), DGs such as Photovoltaic (PV), Wind Turbine (WT) are being connected to a power system. DGs have many advantages, but they also have disadvantage such as generation of reverse flow. Reverse flow can severely disrupt existing protection systems that only consider downstream power flow. The major problems that may arise from reverse power flow are blinding protection and sympathetic tripping. In order to solve such problems, the methods of installing a directional relay or a fault current limiter is proposed. However, this method is inconceivable because of the economics shortage. Therefore, in this paper, a distance relay installed in existing power system is used to solve the protection problem. Modeling of distance relay has been carried out using ElectroMagnetic Transients Program (EMTP), and it has been verified through simulations that the above problems can be solved by a distance relay.

• Nuclear Engineering and Technology
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• v.34 no.3
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• pp.259-267
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• 2002

NFPA-803 has been referred as the Fire Protection Standard at the Nuclear Power Plants of Pressurized Water Reactor. This Standard has been used as the fire protection regulation, containing prescriptive requirements with deterministic methodology. Recently, with cumulative efforts by the U.S. Nuclear Regulatory Commission and Utilities in America to establish a new Standard, including a quantitative evaluation methodology, NFPA-805, the Performance-Based Standard for FIRE Protection for Light Water Reactor Electric Generating Plants was issued and approved by the American National Standards Institute as an American National Standard with an effective date of February 9, 2001. This paper presents an analysis result from the computer modeling for the fire simulation In addition, it proposes the idea that this kind of analytic method can be available for the facilities design of fire prevention and protection fields, as well as an evaluation for the fire suppression system with a quantitative analysis for the thermal phenomena in fire compartments in Nuclear Power Plants.

• Corrosion Science and Technology
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• v.5 no.3
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• pp.106-111
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• 2006

Painting has protected metallic stack but the paint films may be degraded and corrosion problem can be arisen. To protect the painted metal stack, cathodic protection can be applied. If cathodic protection is applied to bare metal, only small area may be protected. However, if cathodic protection is applied to painted metal surface, large area can be protected and the lifetime of paint films can be extended. High corrosion resistant alloys were corroded at a Flue Gas Desulfurization (FGD) facility of power plant within a short period and thus cathodic protection can be used to protect these metals. On the base of computer simulation, if cathodic protection is applied to bare metal in a FGD environment, it was estimated that applied current could almost be spent to protect area near the anode. However, if cathodic protection is applied to high resistant-coated metal, the much larger area from the anode could be effectively protected.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.13 no.6
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• pp.562-567
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• 2020

In this paper, this is a study on the correction of protection relays to monitor temporary power facilities for storage tanks especially transformers to block and protect faults such as insulation breakdown. When an abnormality such as a short circuit or a ground fault occurs in the power system, it is important to detect this quickly cut off the device and equipment in which the fault occurred and separate it from the power system to correct the protection relay so that it does not interfere with power supply. In addition the fault current calculation that accurately applies the fault type and the cause of the fault for protection cooperation will be the most important factor in the correction of the protection relay. For protection coordination a study was conducted on the method of coordination for protection of power facility protection for storage tanks such as over current relay, ground over current relay, under voltage relay, and ground over voltage relay applied to temporary.

• Progress in Superconductivity and Cryogenics
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• v.9 no.3
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• pp.16-20
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• 2007

This paper describes protection system of new distribution power system with superconducting power devices such as HTS cable, HTS transformer, HTS-FCL. First of all, this paper investigates protection systems of Korean power system and then do a basic study on relaying systems in the power system with HTS power devices. For the more detailed results, we did the study using EMTDC relaying system modeling from the viewpoint of superconducting power devices application. Then we proposed some solution for a high resistance fault problem.

• KIEE International Transactions on Power Engineering
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• v.2A no.3
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• pp.89-94
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• 2002

In this paper, a protection system using a Multi-Agent concept for power distribution networks is proposed. Every digital over current relay(OCR) is developed as an agent by adding its own intelligence, self-tuning and communication ability. The main advantage of the Multi-Agent concept is that a group of agents work together to achieve a global goal which is beyond the ability of each individual agent. In order to cope with frequent changes in the network operation condition and faults, an OCR agent, suggested in this paper, is able to detect a fault or a change in the network and find its optimal parameters for protection in an autonomous manner considering information of the whole network obtained by communication between other agents. Through this kind of coordination and information exchanges, not only a local but also a global protective scheme is completed. Simulations in a simple distribution network show the effectiveness of the suggested protection system.