• Journal of Intelligence and Information Systems
• /
• v.1 no.2
• /
• pp.17-32
• /
• 1995

본 논문에서는 추론엔진 (inference engine)내에 퍼지정보 검색부(Fuzzy Information Retrieval part)를 갖는 교통신도 제어 전문가 시스템을 제안한다. 제안하는시스템은 다양하고 복잡한 도로 상화을 고려하여 그에 따른 적절한 주기를 각 도로별로 할당함으로써 원활한 교통 흐름을 제어한다. 추론엔진내의 퍼지정보 검색부는 퍼지 삼각 논리곱을 이용하여 도로의 상황을 분석한 후 각 도로에 맞는 가장 적절한 신호주기를 생성한다.

• The Journal of the Korea Contents Association
• /
• v.9 no.6
• /
• pp.45-52
• /
• 2009

Recently, we started a project development of the digital expert system for the product design supporting in manufacturing industry. This digital expert system is used to the engineers in manufacturing industry for the process control, production management and system management. In this paper, we develop the ontology based inference engine shell for building of expert system. This expert system shell included a various functions which of Korean language supporting, graphical ontology map modeling interface, fuzzy rule definition function and etc. And, we introduce the knowledge representation method for the ontology map building and ontology based fuzzy inferencing method.

• Journal of Advanced Navigation Technology
• /
• v.15 no.3
• /
• pp.449-455
• /
• 2011

In this paper, Proposed controller prevent compressor surge and reduce the acceleration time of the fuel flow control system for turbo-jet engine. Turbo-jet engine controller is designed by applying fuzzy PI+D control algorithm and make an inference by applying Mamdani's inference method and the defuzzification using the center of gravity method. Fuzzy inference results are used as the fuel flow control inputs to prevent compressor surge and flame-out for turbo-jet engine and the controller is designed to converge to the desired speed quickly and safely. Using MATLAB to perform computer simulations verified the performance of the proposed controller.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 1998.05a
• /
• pp.291-294
• /
• 1998

본 논문에서는 퍼지라는 개념을 도입하여 기존의 전문가시스템에서 문제점으로 지적되어 온 불확실성, 모호성의 처리 기능을 부가하여 표현의 영역을 확장, 개선하여, 전문가시스템의 추론 엔진을 적용하는 근사적 유사 추론기법을 분석한다. 그리고 규칙의 조건부와 이에 대응하는 사실간의 유사도를 구하여 이들 규칙의 결론부에 반영하여 결론을 유도하는 근사적 유사 추론기법을 제안한다. 또한 이와 같은 이론적인 연구를 바탕으로 자연언어의 많은 부분을 차지하고 있는 퍼지 개념을 지원하는 당뇨병(의료)진단용 전문가시스템을 설계, 구현하여 기존의 불확실성 관리방안의 단점을 개선하고자 한다.

• The Transactions of the Korea Information Processing Society
• /
• v.5 no.4
• /
• pp.951-958
• /
• 1998

In this paper, we propose a backward reasoning algorithm which can be utilized in the fuzzy Petri-net representation representing fuzzy production rules. The fuzzy Petri-net representation can be used to model a approximate reasoning system and implement a fuzzy inference engine. The proposed algorithm, which uses the proper belief evaluation functions according to fuzzy concepts in antecedentes and consequents of fuzzy production rules, is more closer to human intuition and reasoning than other methods. This algorithm generates the backward reasoning path from the goal to the initial nodes and evaluates the belief value of the goal node using belief evaluation functions.

• Journal of Advanced Navigation Technology
• /
• v.9 no.1
• /
• pp.34-40
• /
• 2005

In this paper we propose a turbojet engine controller of unmanned aircraft based on the Fuzzy-PI algorithm. To prevent any surge or a flame out event during the engine acceleration or deceleration, the PI-type fuzzy controller effectively controls the fuel flow input of the control system. The fuzzy inference rule made by the logarithm function of acceleration error improves the tracking error. Computer simulations applied to the linear model of a turbojet engine show that the proposed method has good tracking performance for the reference acceleration and deceleration commands.

• Journal of Korea Society of Industrial Information Systems
• /
• v.6 no.1
• /
• pp.61-69
• /
• 2001

This study concerns designing effective fuzzy inference rules, which can be used to evaluate other experiment sets for sensory tests. The number of fuzzy inference rules might be determined by the fuzzy division of variables. For the more the number of fuzzy division does not mean the more effectiveness, the number of inference rules should be reduced to improve efficiency of inference engine of expert system. This study verified that its suggested method and inference rules are effective in comparison with the existing studies.

• Journal of Advanced Navigation Technology
• /
• v.17 no.1
• /
• pp.107-114
• /
• 2013

In this paper, we propose controller to control the acceleration of unmanned aircraft turbojet engine. The high-gain observer to estimate the rotational speed of compressor is used, and the turbojet engine controller applying fuzzy heuristic techniques and PID control algorithm are designed. fuzzy PID controller produces the flow control input to prevent the surge and flame-out phenomena at the acceleration and deceleration of the turbojet engine. The standard acceleration is set and the fuel flow control is defined by the fuzzy heuristic. Computer simulations are performed using MATLAB in order to verify the performance of the proposed controller.

• Proceedings of the Korean Information Science Society Conference
• /
• 2011.06a
• /
• pp.100-103
• /
• 2011

최근 스마트폰의 보급이 일반화되면서 보다 개인화된(Personalized) 서비스를 제공하려는 시도가 다각도로 이루어지고 있다. 이러한 시도 중 하나가 사용자의 감성을 인식하여 보다 효과적인 서비스를 제공하려는 것이다. 본 논문에서는 스마트폰으로부터 얻어낸 위치인식정보와 사용자 정보를 베이지안 네트워크를 활용하여 상황정보를 도출한다. 이 상황정보와 사용자의 선호도 정보를 퍼지 추론을 이용하여 얻은 결과 값을 수정된 Valence-Arousal 모델에 매핑하여 사용자의 감성정보를 추출하는 감성 추출 엔진을 제안한다. 유용성 평가를 위해 현재 상용 중인 스마트폰에 제안하는 감성 추출 엔진을 이용, 사용자 감성을 인식하고 적절한 서비스를 추천하는 애플리케이션을 구현하였다.

• Journal of the Institute of Convergence Signal Processing
• /
• v.2 no.3
• /
• pp.50-56
• /
• 2001

As the fuzzy control is applied to servo system, the hardware implementation of the fuzzy information systems requires the high speed operations, short real time control and the small size systems. The aims of this study is to develop hardware of the fuzzy information systems to be apply to servo system. In this paper, we propose a calculation method of approximate reasoning for fuzzy control based on $\alpha$ -level set decomposition of fuzzy sets by quantize $\alpha$ -cuts. This method can be easily implemented with analog hardware. The influence of quantization Bevels of $\alpha$-cuts on output from fuzzy inference engine is investigated. It is concluded that 4 quantization levels give sufficient result for fuzzy control performance of dc servo system. The hardware implementation of proposed operation method and of the defuzzification by gravity center method which is directly converted to PWM actuating signal is also presented. It is verified useful with experiment for dc servo system.