• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2002.05a
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• pp.191-194
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• 2002

기존의 퍼지 제어기는 퍼지 추론시 [0, 1]의 소속도를 갖는 퍼지 소속함수들의 실수연산으로 인하여 연산수행 속도가 저하되는 문제를 가지고 있다 따라서 본 논문에서는 실수연산으로 인하여 야기되었던 속도 저하문제를 해결하기 위한 새로운 퍼지연산 기법으로 실수 값을 갖는 퍼지 소속 함수 값을 정수형 격자(pixel)에 매핑 시켜 정수형 퍼지 소속 함수 값만을 가지고 연산함으로써 기존의 퍼지제어기에 비해 매우 빠른 연산을 수행 할 수 있는 고속 퍼지제어기를 제안한다. 또한 퍼지제어시스템 설계시에 퍼지 입.출력 변수들의 퍼지항들을 입력시킬 수 있는 GUI(Graphic User Interface)를 제공하여 소속함수의 수정 및 퍼지 값 입력시 사용자에게 보다 편리한 환경을 제공한다.

• Journal of the Korean Institute of Intelligent Systems
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• v.7 no.2
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• pp.52-65
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• 1997

This paper presents a design technique of self tuning fuzzy controller for load frequency control of power system. The proposed parameter self tuning algorithm of fuzzy controller is based on the gradient method using four direction vectors which make error between inference values of fuzzy controller and output values of the specially selected optimal controller reduce steepestly. Using input-output data pair obtained from optimal controller, the parameters in antecedent part and in consequent part of fuzzy inference rules are learned and tuned automatically using the proposed gradient method. The related simulation results show that the proposed fuzzy controller is more powerful than the conventional ones for reductions of undershoot and steady-state load frequency deviation and for minimization of settling time.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• v.9 no.2
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• pp.399-402
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• 2005

In this paper, we propose fuzzy logic system that compensates position of robot in robot slip. The fuzzy logic system can infer robot slip in its capability. In order to verify the effectiveness of the proposed method, we performed the simulation for position compensation of robot slip. The results showed a good performance.

• The Journal of Korean Association of Computer Education
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• v.6 no.4
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• pp.95-113
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• 2003

We introduce an AFES(Adaptive Fuzzy Evaluation System) that applies an evaluation system used to existing LCMS(Learning Contents Management System) to a fuzzy reasoning rule. The AFES confers a course level on the learner through a fuzzy diagnostic evaluation before the learner enters a learning course. After the learner completes a learning course through the tailored learning path that is suitable for the learner's level, the AFES confers a final grade on the learner by means of fuzzy final evaluation. The biggest characteristic of the AFES is a grade rule of the final grade. Although different learners get the same number of correct answers to the same number of Questions, AFES flexibly confers the different final grade on the learner by means of the number of 125's fuzzy reasoning rules.

• Proceedings of KOSOMES biannual meeting
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• 2003.05a
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• pp.111-116
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• 2003

최근에는 전문가의 지식과 경험정보가 데이터베이스로 구축된 전문가 시스템의 정보를 이용하여 처리된 결과를 판단하여 안전하고 효율적인 선박운항이 가능하도록 한 지능형 선박에 관한 연구가 활발하게 진행되고 있다. 본 논문에서는 지능형 선박을 구현하기 위한 연구의 일환으로써, 선박의 조타기를 제어하기 위한 지능형 조타 조작 모델을 구현한다. 지능형 시스템을 구현하기 위해서 자연언어를 사용하는 인간의 학습 방법에 기초한 언어지시기반학습(LIBL)기법을 적용하고. 퍼지이론을 이용하여 승선경력이 풍부한 조타수의 경험을 조사 및 분석하여 그 결과를 바탕으로 퍼지 추론에 의해 타각을 제어하기 위한 퍼지 조타 조작 모델을 구현하여 그 효용성을 살펴보았다.

• The Transactions of the Korea Information Processing Society
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• v.3 no.3
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• pp.543-563
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• 1996

In this paper, we propose a Timed Fuzzy Petri Net(TFPN) model as a new model of real-time fuzzy control. The TFPN model, which is useful for fuzzy inference and fuzzy control is an integrated model of Timed PetriNet and Fuzzy Petri Net. Additionally, a Timed Fuzzy Control Language is defined as a textual specification model of fuzzy control rues, and proposed a TFPN modeling method. The TFPN model is a Petri Net formalism of fuzzy control systems. Execution rule is consisted of marking(i.e,fuzzyfication) and firing(i.e,inference and defuzzyfication) procedures. A simple case work by using TFPN model shows us computing time of inference and defuzzyfication is low and uncertainty and visibility of fuzzy control rule are modeled effectively.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.12 no.2
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• pp.38-44
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• 1998

This paper presents an integrated fault diagnosis expert system to assist SCADA operators in local control centers which controls unmanned distribution substations in a power system. The proposed system diagnoses various faults occurred in both substation devices and transmission devices. The system can be easily installed without disturbing main SCADA system. The system simply shares the dynamic information including alarms with main SCADA using dual data link interface. And the proposed expert system utilizes the fuzzy reasoning process in order to consider the uncertainty factor. The system is developed using a low cost personal computer owing to the special modular programming and the meta-inf!'lrence structure. Case studies showed a promising possibility.bility.

• Journal of the Korea Society of Computer and Information
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• v.10 no.1 s.33
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• pp.209-216
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• 2005

Performance assessment has Problems about possibilities of assessment fault by appraisal, fairness, reliability, and validity of grading, ambiguity of grading standard, difficulty about objectivity security etc. This study proposes fuzzy Performance assessment system to solve problem of the conventional performance assessment. This Paper presented an objective and reliable performance assessment method through fuzzy reasoning, design fuzzy membership function and define fuzzy rule analyzing factor that influence in each sacred ground of performance assessment to account principle subject. Also, performance assessment item divides by formation estimation and subject estimation and designed membership function in proposed performance assessment method. Performance assessment result that is worked through fuzzy Performance assessment system can pare down burden about appraisal's fault and provide fair and reliable assessment result through grading that have correct standard and consistency to students.

• The Transactions of the Korea Information Processing Society
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• v.6 no.4
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• pp.977-987
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• 1999

The current traffic signal control systems are operated depending on the pre-planned control scheme or the selected control scheme according to a period of time. The problem with these types of traffic control systems is that they can not cope with variant traffic flows appropriately. Such a problem can be difficult to solve by using binary logic. Therefore, in this 0paper, we propose a traffic signal control system which can deal wit various traffic flows quickly and effectively. The proposed controller is operated under uncertainty and in a fuzzy environment. It show the congestion of road traffic by using fuzzy logic, and it determines the length of green signal by means of a fuzzy inference engine. It modeled using petri-net to verify its validation.

• Proceedings of the Korean Information Science Society Conference
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• 2004.10b
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• pp.541-543
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• 2004

인터넷의 대중화로 인하여 인터넷상에 많은 음악 정보가 존재하게 되었다. 이에 따라서 사용자에게 음악 정보를 손쉽게 접근할 수 있게 해주는 서비스뿐만 아니라, 사용자에게 적절한 음악을 추천해주는 서비스의 중요성도 증가하고 있다. 본 논문에서는 사용자의 상황을 인식하고 사용자와의 대화를 통해서 적절한 음악을 추천해주는 인공 DJ를 제안한다 인공 DJ는 센서로부터 실내 온도, 습도, 조도, 소음을 입력받고, 인터넷을 통하여 날씨 정보를 입력받고, 사용자의 감정추론을 위하여 사용자가 입력하는 문장을 분석하여 Activation-Evaluation Space상에서 사용자의 감정을 표시함으로써 사용자의 주변 상황을 인식하고, 사용자의 성향을 파악하여 IF-THEN 규칙을 만들어 대수학적 연산자(algebraic operator)를 통한 퍼지 추론 방법을 이용하여 적절한 음악을 추천한다. 피험자 10명을 대상으로 실시한 설문조사 결과 제안하는 방법이 유용함을 알 수 있었다.