• 제어로봇시스템학회:학술대회논문집
• /
• 제어로봇시스템학회 1993년도 한국자동제어학술회의논문집(국내학술편); Seoul National University, Seoul; 20-22 Oct. 1993
• /
• pp.398-403
• /
• 1993

A rule based fuzzy expert system to self-tune PID controllers is proposed in this paper. The proposed expert system contains two rule bases, where one is responsible for "Long term tuning" and the other for "Incremental tuning". The rule for "Long term tuning" are extracted from the Wills'map and the knowledge about the implicit relations between PID gains and important long term features of the output response such as overshoot, damping and rise time, etc., while 'Incremental tuning" rules are obtained from the relations between PID gains and short term features, error and change in error. In the PID control environment, the proposed expert system operates in two phases sequentially. In the first phase, the long term tuning is performed until long term features meet their desired values approximately. Then the incremental tuning tarts with PID gains provided by the long term tuning procedure. It is noticeable that the final PID gains obtained in the incremental tuning phase are only the temporal ones. Simulation results show that the proposed rule base for "Long term tuning" provides superior control performance to that of Litt and that further improvement of control performance is obtained by the "Incremental tuning'.ance is obtained by the "Incremental tuning'.ing'.

• KSBB Journal
• /
• 제6권3호
• /
• pp.263-270
• /
• 1991

The optimal cell concentration and dilution rate for maximum ethanol productivity were obtained using dynamic simulation in cell recycled continuous bioreactor. The good control performance was observed using rule-based STR (self-tuning regulator) compared to conventional STR. Rule-base contained the scheme to implement the STR in an efficient on-off way and the scheme for the controlled variable to reach the optimal value in a short time. Since a mathematical model was used to analyze and estimate the changes of the state variables and the parameters, it was possible to understand the physical meaning of the system.

• 한국반도체및디스플레이장비학회:학술대회논문집
• /
• 한국반도체및디스플레이장비학회 2006년도 춘계학술대회
• /
• pp.121-126
• /
• 2006

본 연구는 반도체 산업의 공정에서 자동화를 위한 Solution 개발에 초점을 두었다. Spec-out(불량)이 발생하였을 경우에 엔지니어가 원인을 분석하고 조치를 취하던 이전의 방식을 탈피하여 Expert Knowledge Base System의 On-Line방식으로 전환하고자 한다. 이러한 시스템을 구축하기 위해 공정과 계측간에 발생하는 파라메터들의 상관관계를 수학적으로 도출하였으며, 상관관계들을 이용하여 이탈 발생시 처리를 하기 위한 Rule을 구성하였다. 그리고 이 Rule들을 바탕으로 이탈발생의 원인을 분석하는 추론 시스템을 구성하여 즉각적이고 신속하게 처리를 하기 위한 이탈처리 분석 시스템을 구성하는 방법을 연구하였다.

• 한국정보과학회:학술대회논문집
• /
• 한국정보과학회 2003년도 가을 학술발표논문집 Vol.30 No.2 (3)
• /
• pp.259-261
• /
• 2003

본 논문에서는 미래에 많은 기업들이 경쟁력 향상을 위하여 도입할 것으로 예상되는 규칙 기반의 비즈니스 응용 시스템을 개발하고 운영하는데 필요한 환경을 제공하는 시스템의 구조를 제안하고 그리고 규칙 기반 응용들에게 상호 운영성을 제공하는데 필요한 규칙 표현의 표준화 동향들을 기술하고 있다.

• 한국자동차공학회논문집
• /
• 제13권5호
• /
• pp.163-170
• /
• 2005

Urban transit is a complex system that is combined electrically and mechanically, it is necessary to construct maintenance system for securing safety accompanying high-speed driving and maintaining promptly. Expert system is a computer program which uses numerical or non-numerical domain-specific knowledge to solve problems. In this research, we intend to develop the expert system which diagnose failure causes quickly and display measures. For the development of expert system, standardization of failure code classification system and creation of BOM(Bill Of Materials) have been first performed. Through the analysis of failure history and maintenance manuals, knowledge base has been constructed. Also, for retrieving the procedure of failure diagnosis and repair linking with the knowledge base, we have built RBR(Rule Based Reasoning) engine by pattern matching technique and CBR(Case Based Reasoning) engine by similarity search method. This system has been developed based on web to maximize the accessibility.

• 전기학회논문지
• /
• 제56권5호
• /
• pp.990-992
• /
• 2007

The purpose of this study is to develop a practical gait-event detection system which is necessary for the FES (functional electrical stimulation) control of locomotion in paralyzed patients. The system is comprised of a sensor board and an event recognition algorithm. We focused on the practicality improvement of the system through 1) using accelerometer to get the angle of shank and dispensing with the foot-switches having limitation in indoor or barefoot usage and 2) using a rule-base instead of threshold to determine the heel-off/heel-strike events corresponding the stimulation on/off timing. The sensor signals are transmitted through RF communication and gait-events was detected using the peaks in shank angle. The system could detect two critical gait-events in all five paralyzed patients. The standard deviation of the gait events time from the peaks were smaller when 1.5Hz cutoff frequency was used in the derivation of the shank angle from the acceleration signals.

• 전기학회논문지
• /
• 제61권8호
• /
• pp.1164-1171
• /
• 2012

Recently, machine olfactory systems as an artificial substitute of the human olfactory system are being studied actively because they can scent dangerous gases and identify the type of gases in contamination areas instead of the human. In this paper, we present an effective design method for the gas identification system. Even though dimensionality reduction is the very important part, in pattern analysis, We handled effectively the dimensionality reduction by grouping the sensors of which the measured patterns are similar each other, where genetic algorithms were used for combination optimization. To identify the gas type, we constructed the hierarchical rule base with two frames by using rough set theory. The first frame is to accept measurement characteristics of each sensor and the other one is to reflect the identification patterns of each group. Thus, the proposed methods was able to accomplish effectively dimensionality reduction as well as accurate gas identification. In simulation, we demonstrated the effectiveness of the proposed methods by identifying five types of gases.

• 한국마린엔지니어링학회:학술대회논문집
• /
• 한국마린엔지니어링학회 2002년도 춘계학술대회논문집
• /
• pp.233-238
• /
• 2002

This paper propose the construction of fault diagnosis engine for diesel generator engine and rule inference method to induce rule for fuzzy inference from the monitored data of diesel engine. The proposed fault diagnosis system is constructed the Malfunction Diagnosis Engine(MDE) and Hierarchy of Malfunction Hypotheses(HME), It is Proposed the rule reduction method of knowledge base for concerning data among the various analog data.

• 설비공학논문집
• /
• 제14권7호
• /
• pp.552-559
• /
• 2002

The fault detection and diagnosis (FDD) technology may be applied in order to decrease the energy consumption and the maintenance cost of the air conditioning system. In this study, rule bases and curve fitting models were used to detect faults in an air handling unit. Gradually progressed faults, such as the fan speed degradation, the coil water leakage, the humidifier nozzle clogging, the sensor degradation and the damper stoppage, were applied to the developed FBD system. Simulation results show good detections and diagnoses of these faults. Therefore, this method may be effectively used for the fault detection and diagnosis of the air handling unit.

• 한국의류산업학회지
• /
• 제11권4호
• /
• pp.648-660
• /
• 2009

In this research, an expert system has been developed to select optimum well-matched fusible interlinings with a face fabric. First, a database of face fabrics and fusible interlinings has been constructed. And knowledge acquisition has been performed from the previous studies about the properties of fusible interlinings and fused composites as well as fusing prsocess quality control. Then, a rule-based knowledge-base has been constructed through knowledge classification. Finally, we have constructed an inference engine with the knowledge-base. The expert system enables us to easily select optimum fusible interlinings for a face fabric considering high quality fused composites and fashion trend.