• The Transactions of the Korean Institute of Electrical Engineers A
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• v.49 no.1
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• pp.1-5
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• 2000

This paper presents a new algorithm to restore the de-energized loads in electric power distribution systems for restoration by utilizing object-based structure and heuristic rules without branch and feeder overloading. In order to cope with a complex network configuration and frequent breaker switching operations in distribution systems, the component of power system is described as objects and the information of system configuration is constructed by connecting objects each other. Such a strategy is developed mainly based on the object search algorithm to increase computation efficiency. As a result, the proposed system has been implemented to efficiently deal with large distribution systems by reducing computational burden remarkably compared with the conventional methods.

• Electrical & Electronic Materials
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• v.7 no.2
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• pp.123-129
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• 1994

SONOS EEPROM chips, containing several SONOSFET nonvolatile memories of various channel size, have been fabricated on the basis of the existing n-well CMOS processing technology for 1 Mbit DRAM ($1.2\mu\textrm{m}$.m design rule). All the SONOSFET memories have the triple insulated-gate consisting of 30.angs. tunneling oxide, 205.angs. nitride and 65.angs. blocking oxide. The miniaturization of the devices for the higher density EEPROM and their characteristics alterations accompanied with the scaling-down have been investigated. The stabler operating characteristics were attained by increasing the ratio of the channel width to length. Also, the transfer, switching, retention and degradation characteristics of the most favorable performance devices were presented and discussed.

• Proceedings of the IEEK Conference
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• 1999.06a
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• pp.239-242
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• 1999

In this paper, we report the process/device design of high-speed, high-voltage SOI smart power IC for mobile communication system, high-speed HDD system and the electronic control system of automobiles. The high voltage LDMOS with 70V breakdown voltage under 0.8${\mu}{\textrm}{m}$ design rule, the high voltage bipolar with 40V breakdown voltage for analog signal processing, the high speed bipolar with cut-off frequency over 20㎓ and LDD NMOS for high density were proposed and simulated on a single chip by the simulator DIOS and DESSIS. And we extracted the process/device parameters of the simulated devices.

• Smart Structures and Systems
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• v.19 no.5
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• pp.577-585
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• 2017

In this paper, an adaptive fuzzy sliding mode controller (AFSMC) is designed to reduce dynamic responses of seismically excited structures. In the conventional sliding mode control (SMC), direct implementation of switching-type control law leads to chattering phenomenon which may excite unmodeled high frequency dynamics and may cause vibration in control force. Attenuation of chattering and its harmful effects are done by using fuzzy controller to approximate discontinuous part of the sliding mode control law. In order to prevent time-consuming obtaining of membership functions and reduce complexity of the fuzzy rule bases, adaptive law based on Lyapunov function is designed. To demonstrate the performance of AFSMC method and to compare with that of SMC and fuzzy control, a linear three-story scaled building is investigated for numerical simulation based on the proposed method. The results indicate satisfactory performance of the proposed method superior to those of SMC and fuzzy control.

• Journal of the Korean Institute of Intelligent Systems
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• v.3 no.3
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• pp.56-67
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• 1993

A Class of fuzzy controller based on the variable structure system(VSS) technique in which different structures of controllers are fuzzily switched according to the switching rules in proppsed. The structure of proposed controllers was motivated by the characteristics of position type fuzzy controller and velocity type fuzzy controller ; the former generally gives good performance in transient perod and the latter are capable of reducing steady state error of response. To show the usefulness of the proposed controller, it is applied to several systems that is difficult to stabilize or difficult to get satisfactory responsed by conventional fuzzy controllers.

• Proceedings of the KIEE Conference
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• 1988.07a
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• pp.506-509
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• 1988

This paper describes an effective knowledge acquisition method in the fault diagnosis expert system for the electronic switching system TDX-1A. The knowledge acquisition procedure consists of the knowledge collection, the fault diagnosis modeling and the knowledge representation. Furthermore, to improve the performance of the knowledge bases with rule and frame representation, we showed the knowledge base checking methodlogy by using redundancy and inconsistency check algorithm.

• Proceedings of the Korea Society for Simulation Conference
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• 2001.05a
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• pp.67-71
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• 2001

The main Idea behind the Intelligent Networks (IN) concept Is the separation of switching functionality from the service control, in order to meet various service requirements of subscribers and development 7f new services in time. On the increase of subscriber and for high quality of service, the IN upgrades its service systems, and there are a number of ways depending on the system architecture and the characteristics of services. This paper compares two alternatives, traces the performance of them by means of the simulation technique, and finally puts a rule to select one of them.

• Journal of the Korea Society of Computer and Information
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• v.21 no.11
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• pp.9-16
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• 2016

The central goal of the current paper is to investigate lexical transfer between Korean and English and to identify rule-governed behavior and to provide implications for development of computer-assisted translation(CAT) software for the two languages. It will be shown that Sankoff and Poplack's Free Morpheme Constraint can not account for all the range of data. A constraint is proposed that a set of case-assigners such as verbs, INFL, prepositions, and the possessive marker may not undergo lexical transfer. The translation software is also expected to be equipped with the proposed claim that English verbs are actually borrowed as nouns or as defective verbs to escape from the direct attachment of inflectional morphemes.

• Journal of Electrical Engineering and Technology
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• v.4 no.1
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• pp.66-78
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• 2009

This paper introduces the design of a fuzzy logic controller in conjunction with direct torque control strategy for a Permanent Magnet synchronous machine. A stator flux angle mapping technique is proposed to reduce significantly the size of the rule base to a great extent so that the fuzzy reasoning speed increases. Also, a fuzzy resistance estimator is developed to estimate the change in the stator resistance. The change in the steady state value of stator current for a constant torque and flux reference is used to change the value of stator resistance used by the controller to match the machine resistance.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.17 no.3
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• pp.87-94
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• 2003

When faults occur in a distribution network, blackout loads must be restored as fast as possible to minimize interruption of electric service. This paper presents an expert system to restore distribution networks. The system is designed to minimize switching operations in a heuristic sense by using heuristic rules. The restoration process is converted to the feasible path finding problem in the state space of expert system by application of general topological knowledge base. Multiple load transfer algorithm is proposed to deal with complex situations.