• Journal of the Institute of Convergence Signal Processing
• /
• v.3 no.1
• /
• pp.61-66
• /
• 2002

A fuzzy control strategy is described which is utilized to control the joint angle and tip deflection in single flexible manipulator. In this paper, an existing model for a single flexible manipulator is used for the initial development of an FLC. One FLC is designed to govern the joint angle of the manipulator as it is rotated from one position to another, and the second FLC is designed to attenuate the tip deflection which result from joint angle body motion. Reference Trajectory Command is an important method to reduce vibration in flexible beam. This paper presents a very simple command control shaping which eliminates multiple mode residual vibration in a flexible beam combined parallel fuzzy controller. The effectiveness of proposed scheme is demonstrated through computer simulation.

• Proceedings of the Korea Institute of Convergence Signal Processing
• /
• 2003.06a
• /
• pp.153-156
• /
• 2003

This short paper suggests a control strategy using a stepwise fuzzy moving sliding surface. The moving surface is a Sugeno-type fuzzy system that has the angle of state error vector and the distance from the origin in the phase plane as inputs and a first-order linear differential equation as an output. The surface initially passes arbitrary initial states and subsequently moves towards a predetermined surface via rotating or shifting. the proposed method reduces the reaching and tracking time and improves robustness. The asymptotic stability of the fuzzy sliding surface is proved. The validity of the proposed control scheme is shown in computer simulation for a second-order nonlinear system.

• Journal of the Korean Society of Industry Convergence
• /
• v.4 no.2
• /
• pp.127-132
• /
• 2001

In turning, the chip may be produced in the form of continuous chip or discontinuous chip. The continuous chips are dangerous to the operator and difficult to be handled at high speed machining. The signal of AE(Acoustic Emission) is found out to be related to cutting conditions, tool materials, test conditions and tool geometry in turning. In this study, the relationship between AE signal and chip form was experimentally investigated. The experimental results show that the types of chip form are possible to be classified from the AE signal using fuzzy logic.

• Proceedings of the Korea Institute of Convergence Signal Processing
• /
• 2000.08a
• /
• pp.101-104
• /
• 2000

본 논문은 FLC를 이용한 원격제어 이동로봇이 다수 목적지를 보다 효율적으로 주행하도록 제어하는 것이다. 원격 제어 이동로봇이 전진, 후진, 좌회전, 우회전의 이동 명령을 한 가지씩 수행한 후 멈추는데 발생되는 단점을 보완하기 위해 본 논문은 초음파 센서를 이용하여 얻어진 지형정보를 바탕으로 목적지에 대한 경유점 수를 줄이면서 경유점 간의 이동을 최적한 경로로 주행을 할 수 있도록, 퍼지 논리 제어기를 이용하여 보다 효율적인 제어를 할 수 있는 알고리즘을 연구하였다. 그리고, 이러한 주행 알고리즘을 시뮬레이션을 통해 확인하였다.

• Proceedings of the Korean Institute of Intelligent Systems Conference
• /
• 2006.11a
• /
• pp.69-72
• /
• 2006

급격한 정보화 산업의 발달로 인하여 혁신적인 기술 진화와 함께 이에 기반한 새로운 환경적, 기술적 패러다임이 변화되고 있다. 공간 간 융합과 조화를 극대화 시키고 공간속에서의 충돌과 문제점을 최소화시키기 위한 유비쿼터스 공간의 출현이다. USN에서 많은 수의 작고 다양하고 이질적인 센서 데이터 들이 발생하고 있다. 센서 데이터베이스 시스템에서 수많은 데이터들을 융합하기 위하여 에이전트 기술을 이용하고, 방대하고 애매모호한 데이터를 퍼지이론을 적용하여 데이터를 분류하여 적절한 장소에서 사용자의 욕구에 알맞은 정보를 제공함으로써 효율성과 융통성을 지원하는 방법을 제안한다. 본 논문에서는 이러한 애매모호한 데이터를 적절하게 분류함으로써 시간과 비용을 절약하고 빠른 응답을 사용자에게 전달할 수 있으며 유효적절한 서비스를 사용자의 기호에 맞게 제공함으로써 공간과 사물에 주어진 센서 데이터를 효율적으로 관리 할 수 있는 방법을 제안한다.

• Journal of the Institute of Convergence Signal Processing
• /
• v.16 no.3
• /
• pp.108-114
• /
• 2015

Ballast water is carried by ships to ensure stability, trim and structural integrity. When a ship loads cargo, the ballast water is discharged. When foreign marine microorganisms are introduced into new marine environments, they pose a threat to the local marine ecological system. UV system is commonly used for the disinfection of waste and surface water. This method would not be as efficient because some species do survive to form viable populations, much of the sediment and organisms at the bottom of tanks, and may become serious pests. In this paper, we designed and implemented ballast water treatment system using fuzzy PID controller to prevent lamp damage, and to reduce the formation of the viable populations. The experiments were conducted with ballast water treatment system using fuzzy PID controller with short time exposure to the temperature above $40^{\circ}C$. This system was shown to be effective by significantly reducing bacterial population and lamp life extension through appropriate temperature of ballast water.

• Journal of Convergence for Information Technology
• /
• v.8 no.5
• /
• pp.131-135
• /
• 2018

The heart disease taking the second place of the cause of the death of modern people is a terrible disease that makes sudden death without noticing. To judge the aortic valve disease of heart diseases a name of disease was diagnosed using psychological data provided from physioNet. Aortic valve is a valve of the area that blood is spilled from left ventricle to aorta. Aortic stenosis of heart troubles is a disease when the valve does not open appropriately in contracting the left ventricle to aorta due to narrowed aortic valve. In this paper, 3126 samples of cardiac sound data were used as an experiment data composed of 180 characteristics including normal people and aortic valve stenosis patients. To diagnose normal and aortic valve stenosis patients, NEWFM was utilized. By using an average method of weight as an feature selection method of NEWFM, the result shows 91.0871% accuracy.

• Journal of Internet Computing and Services
• /
• v.13 no.5
• /
• pp.21-31
• /
• 2012

Threat Evaluation(TE) which has air intelligence attained by identifying friend or foe evaluates the target's threat degree, so it provides information to Weapon Assignment(WA) step. Most of TE data are passed by sensor measured values, but existing techniques(fuzzy, bayesian network, and so on) have many weaknesses that erroneous linkages and missing data may fall into confusion in decision making. Therefore we need to efficient Threat Evaluation system that can refine various sensor data's linkages and calculate reliable threat values under unpredictable war situations. In this paper, we suggest new threat evaluation system based on information fusion JDL model, and it is principle that combine fuzzy which is favorable to refine ambiguous relationships with bayesian network useful to inference battled situation having insufficient evidence and to use learning algorithm. Finally, the system's performance by getting threat evaluation on an air defense scenario is presented.

• Journal of Convergence for Information Technology
• /
• v.10 no.4
• /
• pp.55-64
• /
• 2020

This research empirically explores the relationship between types of performance information use, decision making behaviors and performance of government organizations. We measured two types of using performance information, relevance of performance index, variety of performance information, and levels of manager intervention by surveying performance managers of each government ministry or agency and also measured performance by using performance reports. The results of fuzzy-set qualitative comparative analysis suggest that hard use and soft use have impact on performance by combining with characteristics of performance information and managers decision-making by intervening performance management processes.

• Journal of the Korean Institute of Intelligent Systems
• /
• v.21 no.6
• /
• pp.730-736
• /
• 2011

In this paper, we designed the models for pattern classification which can reflect the latest trend in time series. It has been shown that fusion models based on statistical and AI methods are superior to traditional ones for the pattern classification model supporting decision making. Especially, the hit rates of pattern classification models combined with fuzzy theory are relatively increased. The statistical SVM models combined with fuzzy membership function, or the models combining neural network and FCM has shown good performance. BPN, PNN, FNN, FCM, SVM, FSVM, Decision Tree, Time Series Analysis, and Regression Analysis were used for pattern classification models in the experiments of this paper. The economical indices DB with time series properties of the financial market(Korea, KOSPI200 DB) and the electrocardiogram DB of arrhythmia patients in hospital emergencies(USA, MIT-BIH DB) were used for data base.